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  • 251.
    Abels, Esther
    et al.
    PathAI, MA USA.
    Pantanowitz, Liron
    Univ Pittsburgh, PA USA.
    Aeffner, Famke
    Amgen Inc, CA USA.
    Zarella, Mark D.
    Drexel Univ, PA 19104 USA.
    van der Laak, Jeroen
    Linköpings universitet, Institutionen för medicin och hälsa, Avdelningen för radiologiska vetenskaper. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Radboud Univ Nijmegen, Netherlands.
    Bui, Marilyn M.
    H Lee Moffitt Canc Ctr and Res Inst, FL USA.
    Vemuri, Venkata N. P.
    Chan Zuckerberg Biohub, CA USA.
    Parwani, Anil V.
    Ohio State Univ, OH 43210 USA.
    Gibbs, Jeff
    Hyman Phelps and McNamara PC, DC USA.
    Agosto-Arroyo, Emmanuel
    H Lee Moffitt Canc Ctr and Res Inst, FL USA.
    Beck, Andrew H.
    PathAI, MA USA.
    Kozlowski, Cleopatra
    Genentech Inc, CA 94080 USA.
    Computational pathology definitions, best practices, and recommendations for regulatory guidance: a white paper from the Digital Pathology Association2019Ingår i: Journal of Pathology, ISSN 0022-3417, E-ISSN 1096-9896, Vol. 249, nr 3, s. 286-294Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    In this white paper, experts from the Digital Pathology Association (DPA) define terminology and concepts in the emerging field of computational pathology, with a focus on its application to histology images analyzed together with their associated patient data to extract information. This review offers a historical perspective and describes the potential clinical benefits from research and applications in this field, as well as significant obstacles to adoption. Best practices for implementing computational pathology workflows are presented. These include infrastructure considerations, acquisition of training data, quality assessments, as well as regulatory, ethical, and cyber-security concerns. Recommendations are provided for regulators, vendors, and computational pathology practitioners in order to facilitate progress in the field. (c) 2019 The Authors. The Journal of Pathology published by John Wiley amp; Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

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  • 252.
    Abelsson, J.
    et al.
    NU Hospital Organization, Uddevalla.
    Merup, M.
    Karolinska Universitetssjukhuset, Huddinge.
    Birgegård, G.
    Uppsala University.
    WeisBjerrum, O.
    Rigshospitalet, University of Copenhagen.
    Brinch, L.
    Rikshospitalet, Oslo University Hospital.
    Brune, M.
    Sahlgrenska Universitetssjukhuset, Göteborg.
    Johansson, P.
    NU Hospital Organization, Uddevalla.
    Kauppila, M.
    Turku University Hospital, Finland.
    Lenhoff, S.
    Skåne University Hospital.
    Liljeholm, M.
    Norrlands Universitetssjukhus, Umeå.
    Malm, Claes
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Onkologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Centrum för kirurgi, ortopedi och cancervård, Hematologiska kliniken US.
    Remes, K.
    Turku University Hospital, Finland.
    Vindelöv, L.
    Rigshospitalet, University of Copenhagen.
    Andréasson, Björn
    NU Hospital Organization, Uddevalla.
    The outcome of allo-HSCT for 92 patients with myelofibrosis in the Nordic countries2012Ingår i: Bone Marrow Transplantation, ISSN 0268-3369, E-ISSN 1476-5365, Vol. 47, nr 3, s. 380-386Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Between 1982 and 2009 a total of 92 patients with myelofibrosis (MF) in chronic phase underwent allo-SCT in nine Nordic transplant centers. Myeloablative conditioning (MAC) was given to 40 patients, and reduced intensity conditioning (RIC) was used in 52 patients. The mean age in the two groups at transplantation was 46±12 and 55±8 years, respectively (P<0.001). When adjustment for age differences was made, the survival of the patients treated with RIC was significantly better (P=0.003). Among the RIC patients, the survival was significantly (P=0.003) better for the patients with age <60 years (a 10-year survival close to 80%) than for the older patients. The type of stem cell donor did not significantly affect the survival. No significant difference was found in TRM at 100 days between the MAC- and the RIC-treated patients. The probability of survival at 5 years was 49% for the MAC-treated patients and 59% in the RIC group (P=0.125). Patients treated with RIC experienced significantly less aGVHD compared with patients treated with MAC (P<0.001). The OS at 5 years was 70, 59 and 41% for patients with Lille score 0, 1 and 2, respectively (P=0.038, when age adjustment was made). Twenty-one percent of the patients in the RIC group were given donor lymphocyte infusion because of incomplete donor chimerism, compared with none of the MAC-treated patients (P<0.002). Nine percent of the patients needed a second transplant because of graft failure, progressive disease or transformation to AML, with no significant difference between the groups. Our conclusions are (1) allo-SCT performed with RIC gives a better survival compared with MAC. (2) age over 60 years is strongly related to a worse outcome and (3) patients with higher Lille score had a shorter survival.Bone Marrow Transplantation advance online publication, 9 May 2011; doi:10.1038/bmt.2011.91.

  • 253.
    Aberg, D
    et al.
    Royal Inst Technol, SE-16440 Kista, Sweden Linkoping Univ, Dept Phys & Measurement Technol, SE-58183 Linkoping, Sweden.
    Storasta, Liutauras
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Halvledarmaterial.
    Hallen, A
    Royal Inst Technol, SE-16440 Kista, Sweden Linkoping Univ, Dept Phys & Measurement Technol, SE-58183 Linkoping, Sweden.
    Svensson, BG
    Implantation temperature dependent deep level defects in 4H-SiC2001Ingår i: Materials Science Forum, Vols. 353-356, 2001, Vol. 353-3, s. 443-446Konferensbidrag (Refereegranskat)
    Abstract [en]

    Deep level transient spectroscopy spectra of the near Z-defect region (150-350K) were investigated for B implanted samples of low doses (10(8)-10(9) cm(-2)). For 300 degreesC implantation, a level at an energy of 0.41 eV below the conduction hand edge was found, referred to as the S-level. The S-center was shown to form in both implanted and electron irradiated 4H-SiC, either after room temperature (R.T.) implantation followed by mild heat treatments or lung R.T. storage (several months) or after 200-300 degreesC implantations/irradiations. The S-center was found to anneal out at temperatures above 250 degreesC.

  • 254.
    Aberg, Fredrik
    et al.
    Univ Helsinki, Finland; Sahlgrens Univ Hosp, Sweden.
    Danford, Christopher J.
    Beth Israel Deaconess Med Ctr, MA 02215 USA.
    Thiele, Maja
    Odense Univ Hosp, Denmark; Univ Southern Denmark, Denmark.
    Talback, Mats
    Karolinska Inst, Sweden.
    Rasmussen, Ditlev Nytoft
    Odense Univ Hosp, Denmark.
    Jiang, Z. Gordon
    Beth Israel Deaconess Med Ctr, MA 02215 USA.
    Hammar, Niklas
    Karolinska Inst, Sweden.
    Nasr, Patrik
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Centrum för kirurgi, ortopedi och cancervård, Mag- tarmmedicinska kliniken.
    Ekstedt, Mattias
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Centrum för kirurgi, ortopedi och cancervård, Mag- tarmmedicinska kliniken.
    But, Anna
    Univ Helsinki, Finland; Helsinki Univ Hosp, Finland.
    Puukka, Pauli
    Univ Helsinki, Finland.
    Krag, Aleksander
    Odense Univ Hosp, Denmark; Univ Southern Denmark, Denmark.
    Sundvall, Jouko
    Finnish Inst Hlth & Welf, Finland.
    Erlund, Iris
    Finnish Inst Hlth & Welf, Finland.
    Salomaa, Veikko
    Finnish Inst Hlth & Welf, Finland.
    Stal, Per
    Karolinska Univ Hosp, Sweden; Karolinska Inst, Sweden.
    Kechagias, Stergios
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Centrum för kirurgi, ortopedi och cancervård, Mag- tarmmedicinska kliniken.
    Hultcrantz, Rolf
    Karolinska Inst, Sweden.
    Lai, Michelle
    Beth Israel Deaconess Med Ctr, MA 02215 USA.
    Afdhal, Nezam
    Beth Israel Deaconess Med Ctr, MA 02215 USA.
    Jula, Antti
    Finnish Inst Hlth & Welf, Finland.
    Mannisto, Satu
    Finnish Inst Hlth & Welf, Finland.
    Lundqvist, Annamari
    Finnish Inst Hlth & Welf, Finland.
    Perola, Markus
    Finnish Inst Hlth & Welf, Finland.
    Farkkila, Martti
    Univ Helsinki, Finland.
    Hagstrom, Hannes
    Karolinska Univ Hosp, Sweden; Karolinska Inst, Sweden.
    A Dynamic Aspartate-to-Alanine Aminotransferase Ratio Provides Valid Predictions of Incident Severe Liver Disease2021Ingår i: HEPATOLOGY COMMUNICATIONS, ISSN 2471-254X, Vol. 5, nr 6, s. 1021-1035Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aspartate-to-alanine aminotransferase ratio (AAR) is associated with liver fibrosis, but its predictive performance is suboptimal. We hypothesized that the association between AAR and liver disease depends on absolute transaminase levels and developed and validated a model to predict liver-related outcomes in the general population. A Cox regression model based on age, AAR, and alanine aminotransferase (ALT) level (dynamic AAR [dAAR]) using restricted cubic splines was developed in Finnish population-based health-examination surveys (FINRISK, 2002-2012; n = 18,067) with linked registry data for incident liver-related hospitalizations, hepatocellular carcinoma, or liver death. The model was externally validated for liver-related outcomes in a Swedish population cohort (Swedish Apolipoprotein Mortality Risk [AMORIS] subcohort; n = 126,941) and for predicting outcomes and/or prevalent fibrosis/cirrhosis in biopsied patients with nonalcoholic fatty liver disease (NAFLD), chronic hepatitis C, or alcohol-related liver disease (ALD). The dynamic AAR model predicted liver-related outcomes both overall (optimism-corrected C-statistic, 0.81) and in subgroup analyses of the FINRISK cohort and identified persons with &gt;10% risk for liver-related outcomes within 10 years. In independent cohorts, the C-statistic for predicting liver-related outcomes up to a 10-year follow-up was 0.72 in the AMORIS cohort, 0.81 in NAFLD, and 0.75 in ALD. Area-under-the-curve (AUC) for detecting prevalent cirrhosis was 0.80-0.83 in NAFLD, 0.80 in hepatitis C, but only 0.71 in ALD. In ALD, model performance improved when using aspartate aminotransferase instead of ALT in the model (C-statistic, 0.84 for outcome; AUC, 0.82 for prevalent cirrhosis). Conclusion: A dAAR score provides prospective predictions for the risk of incident severe liver outcomes in the general population and helps detect advanced liver fibrosis/cirrhosis. The dAAR score could potentially be used for screening the unselected general population and as a trigger for further liver evaluations.

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  • 255.
    Aberger, Martin
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik. Linköpings universitet, Tekniska högskolan.
    Effects of Nonlinearities in Black Box Identification of an Industrial Robot2000Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This paper discusses effects of nonlinearities in black box identification of one axis of a robot. The used data come from a commercial ABB robot, IRB1400. A three-mass flexible model for the robot was built in MathModelica. The nonlinearities in the model are nonlinear friction and backlash in the gear box.

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  • 256.
    Abeysekera, Ramanika
    Linköpings universitet, Institutionen för datavetenskap.
    Effects of system integration in an organization: A case study carried out in the photo and home electronics branch2005Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [en]

    Organizations often have information systems belonging to different computer generations. These systems contain much valuable data to the organizations concerned. However, these systems are often unable to communicate with each other, due to incompatibilities. Moreover, replacing these systems with new systems is also very costly. Therefore the latest trend is integrating the existing systems with each other with the help of different system integration technologies. When the systems are integrated with new technology they bring about various effects to the organizations in concern.

    The purpose of this thesis is to find out how system integration affects an organization in the photo and home electronics branch, namely Expert. The questions that will be raised in this thesis are how does system integration affect the organization’s work processes and how does system integration affect the organisation’s employees. I have studied how system integration has affected the work processes and employees of the retail stores. In order to find answers to these questions three qualitative interviews were carried out. One interview took place in the central organization and the rest in retail stores in Linköping.

    There are many reasons, which led Expert towards using system integration. Some of the main reasons are increased profitability and decreased costs for maintenance and upgrading of different systems. Further, the retail stores required better information channelling and streamlining of work processes in order to provide salesmen at retail stores possibility to concentrate more on customers by minimising administrative work.

    I have found that system integration has affected the organization’s work processes and its employees both positively and negatively, in other words system integration has helped Expert to decrease administration work, provided salesmen at retail stores more time to deliver better service to customers, has automated key work processes saving time and reducing redundancy of work. Even if, the organization is quite satisfied with the benefits the existing system integration technologies have rendered to them, there are many more privileges, which can be achieved.

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  • 257.
    Abgrall, Remi
    et al.
    Institute of Mathematics, University of Zurich, Switzerland.
    Nordström, Jan
    Linköpings universitet, Matematiska institutionen, Beräkningsmatematik. Linköpings universitet, Tekniska fakulteten. Department of Mathematics and Applied Mathematics, University of Johannesburg, South Africa.
    Öffner, Philipp
    Institute of Mathematics, University of Zurich, Switzerland. Institute of Mathematics, Johannes Gutenberg-Universtiy, Germany.
    Tokareva, Svetlana
    Theoretical Division, Applied Mathematics and Plasma Physics Group (T-5), Los Alamos National Laboratory, USA.
    Analysis of the SBP-SAT Stabilization for Finite Element Methods Part I: Linear Problems2020Ingår i: Journal of Scientific Computing, ISSN 0885-7474, E-ISSN 1573-7691, Vol. 85, nr 2, artikel-id 43Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In the hyperbolic community, discontinuous Galerkin (DG) approaches are mainly applied when finite element methods are considered. As the name suggested, the DG framework allows a discontinuity at the element interfaces, which seems for many researchers a favorable property in case of hyperbolic balance laws. On the contrary, continuous Galerkin methods appear to be unsuitable for hyperbolic problems and there exists still the perception that continuous Galerkin methods are notoriously unstable. To remedy this issue, stabilization terms are usually added and various formulations can be found in the literature. However, this perception is not true and the stabilization terms are unnecessary, in general. In this paper, we deal with this problem, but present a different approach. We use the boundary conditions to stabilize the scheme following a procedure that are frequently used in the finite difference community. Here, the main idea is to impose the boundary conditions weakly and specific boundary operators are constructed such that they guarantee stability. This approach has already been used in the discontinuous Galerkin framework, but here we apply it with a continuous Galerkin scheme. No internal dissipation is needed even if unstructured grids are used. Further, we point out that we do not need exact integration, it suffices if the quadrature rule and the norm in the differential operator are the same, such that the summation-by-parts property is fulfilled meaning that a discrete Gauss Theorem is valid. This contradicts the perception in the hyperbolic community that stability issues for pure Galerkin scheme exist. In numerical simulations, we verify our theoretical analysis.

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  • 258.
    Abgrall, Remi
    et al.
    University of Zurich, Switzerland.
    Nordström, Jan
    Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Matematiska institutionen, Tillämpad matematik. University of Johannesburg, South Africa.
    Öffner, Philipp
    University of Zurich, Switzerland.
    Tokareva, Svetlana
    Los Alamos National Laboratory, USA.
    Analysis of the SBP-SAT Stabilization for Finite Element Methods Part II: Entropy Stability2023Ingår i: Communications on Applied Mathematics and Computation, ISSN 2096-6385, Vol. 5, nr 2, s. 573-595Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In the hyperbolic research community, there exists the strong belief that a continuous Galerkin scheme is notoriously unstable and additional stabilization terms have to be added to guarantee stability. In the first part of the series [6], the application of simultaneous approximation terms for linear problems is investigated where the boundary conditions are imposed weakly. By applying this technique, the authors demonstrate that a pure continuous Galerkin scheme is indeed linearly stable if the boundary conditions are imposed in the correct way. In this work, we extend this investigation to the nonlinear case and focus on entropy conservation. By switching to entropy variables, we provide an estimation of the boundary operators also for nonlinear problems, that guarantee conservation. In numerical simulations, we verify our theoretical analysis.

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  • 259.
    Abidi, L.
    et al.
    Maastricht University, Netherlands.
    Oenema, A.
    Maastricht University, Netherlands.
    Nilsen, Per
    Linköpings universitet, Institutionen för medicin och hälsa, Avdelningen för samhällsmedicin. Linköpings universitet, Medicinska fakulteten.
    Anderson, P.
    Maastricht University, Netherlands; Newcastle University, England.
    van de Mheen, D.
    Maastricht University, Netherlands; IVO Addict Research Institute, Netherlands; Erasmus MC, Netherlands.
    Strategies to Overcome Barriers to Implementation of Alcohol Screening and Brief Intervention in General Practice: a Delphi Study Among Healthcare Professionals and Addiction Prevention Experts2016Ingår i: Prevention Science, ISSN 1389-4986, E-ISSN 1573-6695, Vol. 17, nr 6, s. 689-699Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Despite the evidence base, alcohol screening and brief intervention (ASBI) have rarely been integrated into routine clinical practice. The aim of this study is to identify strategies that could tackle barriers to ASBI implementation in general practice by involving primary healthcare professionals and addiction prevention experts. A three-round online Delphi study was carried out in the Netherlands. The first-round questionnaire consisted of open-ended questions to generate ideas about strategies to overcome barriers. In the second round, participants were asked to indicate how applicable they found each strategy. Items without consensus were systematically fed back with group median ratings and interquartile range (IQR) scores in the third-round questionnaire. In total, 39 out of 69 (57 %) invited participants enrolled in the first round, 214 participants completed the second round, and 144 of these (67 %) completed the third-round questionnaire. Results show that participants reached consensus on 59 of 81 strategies, such as the following: (1) use of E-learning technology, (2) symptom-specific screening by general practitioners (GPs) and/or universal screening by practice nurses, (3) reimbursement incentives, (4) supportive materials, (5) clear guidelines, (6) service provision of addiction care centers, and (7) more publicity in the media. This exploratory study identified a broad set of strategies that could potentially be used for overcoming barriers to ASBI implementation in general practice and paves the way for future research to experimentally test the identified implementation strategies using multifaceted approaches.

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  • 260.
    Abidi, Latifa
    et al.
    Maastricht Univ, Netherlands.
    Nilsen, Per
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för samhälle och hälsa. Linköpings universitet, Medicinska fakulteten.
    Karlsson, Nadine
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för samhälle och hälsa. Linköpings universitet, Medicinska fakulteten.
    Skagerström, Janna
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för samhälle och hälsa. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Regionledningskontoret, Forskningsstrategiska enheten.
    ODonnell, Amy
    Newcastle Univ, England.
    Conversations about alcohol in healthcare: cross-sectional surveys in the Netherlands and Sweden2020Ingår i: BMC Public Health, E-ISSN 1471-2458, BMC PUBLIC HEALTH, Vol. 20, nr 1Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background

    This study evaluated and compared the extent, duration, contents, experiences and effects of alcohol conversations in healthcare in the Netherlands and Sweden in 2017.

    Methods

    Survey data in the Netherlands and Sweden were collected through an online web panel. Subjects were 2996 participants (response rate: 50.8%) in Sweden and 2173 (response rate: 82.2%) in the Netherlands. Data was collected on socio-demographics, alcohol consumption, healthcare visits in the past 12 months, number of alcohol conversations, and characteristics of alcohol conversations (duration, contents, experience, effects).

    Results

    Results showed that Swedish respondents were more likely to have had alcohol conversations (OR = 1.99; 95%CI = 1.64–2.41; p = < 0.001) compared to Dutch respondents. In Sweden, alcohol conversations were more often perceived as routine (p = < 0.001), were longer (p = < 0.001), and more often contained verbal information about alcohol’s health effects (p = 0.007) or written information (p = 0.001) than in the Netherlands. In Sweden, 40+ year-olds were less likely to report a positive effect compared to the youngest respondents. In the Netherlands, men, sick-listed respondents, and risky drinkers, and in Sweden those that reported “other” occupational status such as parental leave, were more likely to have had alcohol conversations.

    Conclusions

    The results suggest that alcohol conversations are more common in healthcare practice in Sweden than in the Netherlands. However, positive effects of alcohol conversations were less likely to be reported among older respondents in Sweden. Our results indicate that alcohol preventative work should be improved in both countries, with more focus on risky drinkers and the content of the conversations in Sweden, and expanding alcohol screening in the Netherlands.

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  • 261. Beställ onlineKöp publikationen >>
    Abidin, Aysajan
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Authentication in Quantum Key Distribution: Security Proof and Universal Hash Functions2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Quantum Key Distribution (QKD) is a secret key agreement technique that consists of two parts: quantum transmission and measurement on a quantum channel, and classical post-processing on a public communication channel. It enjoys provable unconditional security provided that the public communication channel is immutable. Otherwise, QKD is vulnerable to a man-in-the-middle attack. Immutable public communication channels, however, do not exist in practice. So we need to use authentication that implements the properties of an immutable channel as well as possible. One scheme that serves this purpose well is the Wegman-Carter authentication (WCA), which is built upon Almost Strongly Universal2 (ASU2) hashing. This scheme uses a new key in each authentication attempt to select a hash function from an ASU2 family, which is then used to generate the authentication tag for a message.

    The main focus of this dissertation is on authentication in the context of QKD. We study ASU2 hash functions, security of QKD that employs a computationally secure authentication, and also security of authentication with a partially known key. Specifically, we study the following.

    First, Universal hash functions and their constructions are reviewed, and as well as a new construction of ASU2 hash functions is presented. Second, security of QKD that employs a specific computationally secure authentication is studied. We present detailed attacks on various practical implementations of QKD that employs this authentication. We also provide countermeasures and prove necessary and sufficient conditions for upgrading the security of the authentication to the level of unconditional security. Third, Universal hash function based multiple authentication is studied. This uses a fixed ASU2 hash function followed by one-time pad encryption, to keep the hash function secret. We show that the one-time pad is necessary in every round for the authentication to be unconditionally secure. Lastly, we study security of the WCA scheme, in the case of a partially known authentication key. Here we prove tight information-theoretic security bounds and also analyse security using witness indistinguishability as used in the Universal Composability framework.

    Delarbeten
    1. New Universal Hash Functions
    Öppna denna publikation i ny flik eller fönster >>New Universal Hash Functions
    2012 (Engelska)Ingår i: Lecture Notes in Computer Science, Vol. 7242 / [ed] Frederik Armknecht and Stefan Lucks, Springer Berlin Heidelberg , 2012, s. 99-108Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Universal hash functions are important building blocks for unconditionally secure message authentication codes. In this paper, we present a new construction of a class of Almost Strongly Universal hash functions with much smaller description (or key) length than the Wegman-Carter construction. Unlike some other constructions, our new construction has a very short key length and a security parameter that is independent of the message length, which makes it suitable for authentication in practical applications such as Quantum Cryptography.

    Ort, förlag, år, upplaga, sidor
    Springer Berlin Heidelberg, 2012
    Serie
    Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349 ; 7242
    Nationell ämneskategori
    Annan elektroteknik och elektronik
    Identifikatorer
    urn:nbn:se:liu:diva-84711 (URN)10.1007/978-3-642-34159-5_7 (DOI)978-3-642-34158-8 (ISBN)978-3-642-34159-5 (ISBN)
    Konferens
    4th Western European Workshop on Research in Cryptology, WEWoRC 2011, Weimar, Germany, July 20-22, 2011
    Projekt
    ICG QC
    Tillgänglig från: 2012-10-18 Skapad: 2012-10-17 Senast uppdaterad: 2018-01-31
    2. Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"
    Öppna denna publikation i ny flik eller fönster >>Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"
    2009 (Engelska)Ingår i: International Journal of Quantum Information, ISSN 0219-7499, Vol. 7, nr 5, s. 1047-1052Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In this paper, we review and comment on "A novel protocol-authentication algorithm ruling out a man-in-the-middle attack in quantum cryptography" [M. Peev et al., Int. J. Quant. Inf. 3 (2005) 225]. In particular, we point out that the proposed primitive is not secure when used in a generic protocol, and needs additional authenticating properties of the surrounding quantum-cryptographic protocol.

    Nyckelord
    Quantum cryptography, quantum key distribution, authentication
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-20405 (URN)10.1142/S0219749909005754 (DOI)
    Projekt
    ICG QC
    Tillgänglig från: 2009-09-08 Skapad: 2009-09-07 Senast uppdaterad: 2019-08-15Bibliografiskt granskad
    3. Attacks on quantum key distribution protocols that employ non-ITS authentication
    Öppna denna publikation i ny flik eller fönster >>Attacks on quantum key distribution protocols that employ non-ITS authentication
    Visa övriga...
    2016 (Engelska)Ingår i: Quantum Information Processing, ISSN 1570-0755, E-ISSN 1573-1332, Vol. 15, nr 1, s. 327-362Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    We demonstrate how adversaries with unbounded computing resources can break Quantum Key Distribution (QKD) protocols which employ a particular message authentication code suggested previously. This authentication code, featuring low key consumption, is not Information-Theoretically Secure (ITS) since for each message the eavesdropper has intercepted she is able to send a different message from a set of messages that she can calculate by finding collisions of a cryptographic hash function. However, when this authentication code was introduced it was shown to prevent straightforward Man-In-The-Middle (MITM) attacks against QKD protocols.

    In this paper, we prove that the set of messages that collide with any given message under this authentication code contains with high probability a message that has small Hamming distance to any other given message. Based on this fact we present extended MITM attacks against different versions of BB84 QKD protocols using the addressed authentication code; for three protocols we describe every single action taken by the adversary. For all protocols the adversary can obtain complete knowledge of the key, and for most protocols her success probability in doing so approaches unity.

    Since the attacks work against all authentication methods which allow to calculate colliding messages, the underlying building blocks of the presented attacks expose the potential pitfalls arising as a consequence of non-ITS authentication in QKDpostprocessing. We propose countermeasures, increasing the eavesdroppers demand for computational power, and also prove necessary and sufficient conditions for upgrading the discussed authentication code to the ITS level.

    Ort, förlag, år, upplaga, sidor
    Springer Publishing Company, 2016
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-91260 (URN)10.1007/s11128-015-1160-4 (DOI)000372876800020 ()
    Projekt
    ICG QC
    Anmärkning

    Vid tiden för disputation förelåg publikationen som manuskript

    Funding agencies: Vienna Science and Technology Fund (WWTF) [ICT10-067]; Austrian Research Promotion Agency (FFG) [Bridge-2364544]

    Tillgänglig från: 2013-04-18 Skapad: 2013-04-18 Senast uppdaterad: 2019-08-15Bibliografiskt granskad
    4. On Security of Universal Hash Function Based Multiple Authentication
    Öppna denna publikation i ny flik eller fönster >>On Security of Universal Hash Function Based Multiple Authentication
    2012 (Engelska)Ingår i: Lecture Notes in Computer Science, Vol. 7618 / [ed] Chim, Tat Wing and Yuen, Tsz Hon, 2012, s. 303-310Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Universal hash function based multiple authentication was originally proposed by Wegman and Carter in 1981. In this authentication, a series of messages are authenticated by first hashing each message by a fixed (almost) strongly universal$_2$ hash function and then encrypting the hash value with a preshared one-time pad. This authentication is unconditionally secure. In this paper, we show that the unconditional security cannot be guaranteed if the hash function output for the first message is not encrypted, as remarked in [Atici and Stinson, CRYPTO '96. LNCS, vol. 1109]. This means that it is not only sufficient, but also necessary, to encrypt the hash of every message to be authenticated in order to have unconditional security. The security loss is demonstrated by a simple existential forgery attack.

    Serie
    Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349 ; 7618
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-84732 (URN)10.1007/978-3-642-34129-8_27 (DOI)978-3-642-34128-1 (ISBN)978-3-642-34129-8 (ISBN)
    Konferens
    14th International Conference on Information and Communications Security, ICICS 2012, Hong Kong, China, October 29-31, 2012
    Projekt
    ICG QC
    Tillgänglig från: 2012-10-18 Skapad: 2012-10-18 Senast uppdaterad: 2018-02-12
    5. Direct proof of security of Wegman-Carter authentication with partially known key
    Öppna denna publikation i ny flik eller fönster >>Direct proof of security of Wegman-Carter authentication with partially known key
    2014 (Engelska)Ingår i: Quantum Information Processing, ISSN 1570-0755, E-ISSN 1573-1332, Vol. 13, nr 10, s. 2155-2170Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Information-theoretically secure (ITS) authentication is needed in Quantum Key Distribution (QKD). In this paper, we study security of an ITS authentication scheme proposed by Wegman& Carter, in the case of partially known authentication key. This scheme uses a new authentication key in each authentication attempt, to select a hash function from an Almost Strongly Universal2 hash function family. The partial knowledge of the attacker is measured as the trace distance between the authentication key distribution and the uniform distribution; this is the usual measure in QKD. We provide direct proofs of security of the scheme, when using partially known key, first in the information-theoretic setting and then in terms of witness indistinguishability as used in the Universal Composability (UC) framework. We find that if the authentication procedure has a failure probability ε and the authentication key has an ε´ trace distance to the uniform, then under ITS, the adversary’s success probability conditioned on an authentic message-tag pair is only bounded by ε +|Ƭ|ε´, where |Ƭ| is the size of the set of tags. Furthermore, the trace distance between the authentication key distribution and the uniform increases to |Ƭ|ε´ after having seen an authentic message-tag pair. Despite this, we are able to prove directly that the authenticated channel is indistinguishable from an (ideal) authentic channel (the desired functionality), except with probability less than ε + ε´. This proves that the scheme is (ε + ε´)-UC-secure, without using the composability theorem.

    Ort, förlag, år, upplaga, sidor
    Springer, 2014
    Nyckelord
    Authentication, Strongly Universal hash functions, Partially known key, Trace distance, Universal Composability, Quantum Key Distribution.
    Nationell ämneskategori
    Elektroteknik och elektronik
    Identifikatorer
    urn:nbn:se:liu:diva-91264 (URN)10.1007/s11128-013-0641-6 (DOI)000341842000002 ()
    Projekt
    ICG QC
    Tillgänglig från: 2013-04-18 Skapad: 2013-04-18 Senast uppdaterad: 2017-12-06Bibliografiskt granskad
    Ladda ner fulltext (pdf)
    Authentication in Quantum Key Distribution: Security Proof and Universal Hash Functions
    Ladda ner (pdf)
    omslag
  • 262.
    Abidin, Aysajan
    Linköpings universitet, Institutionen för systemteknik, Informationskodning.
    On Security of Universal Hash Function Based Multiple Authentication2012Ingår i: Lecture Notes in Computer Science, Vol. 7618 / [ed] Chim, Tat Wing and Yuen, Tsz Hon, 2012, s. 303-310Konferensbidrag (Refereegranskat)
    Abstract [en]

    Universal hash function based multiple authentication was originally proposed by Wegman and Carter in 1981. In this authentication, a series of messages are authenticated by first hashing each message by a fixed (almost) strongly universal$_2$ hash function and then encrypting the hash value with a preshared one-time pad. This authentication is unconditionally secure. In this paper, we show that the unconditional security cannot be guaranteed if the hash function output for the first message is not encrypted, as remarked in [Atici and Stinson, CRYPTO '96. LNCS, vol. 1109]. This means that it is not only sufficient, but also necessary, to encrypt the hash of every message to be authenticated in order to have unconditional security. The security loss is demonstrated by a simple existential forgery attack.

  • 263. Beställ onlineKöp publikationen >>
    Abidin, Aysajan
    Linköpings universitet, Matematiska institutionen, Tillämpad matematik. Linköpings universitet, Tekniska högskolan.
    Weaknesses of Authentication in Quantum Cryptography and Strongly Universal Hash Functions2010Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Authentication is an indispensable part of Quantum Cryptography, which is an unconditionally secure key distribution technique based on the laws of nature. Without proper authentication, Quantum Cryptography is vulnerable to “man-in-the-middle” attacks. Therefore, to guarantee unconditional security of any Quantum Cryptographic protocols, the authentication used must also be unconditionally secure. The standard in Quantum Cryptography is to use theWegman-Carter authentication, which is unconditionally secure and is based on the idea of universal hashing.

    In this thesis, we first investigate properties of a Strongly Universal hash function family to facilitate understanding the properties of (classical) authentication used in Quantum Cryptography. Then, we study vulnerabilities of a recently proposed authentication protocol intended to rule out a "man-in-the-middle" attack on Quantum Cryptography. Here, we point out that the proposed authentication primitive is not secure when used in a generic Quantum Cryptographic protocol. Lastly, we estimate the lifetime of authentication using encrypted tags when the encryption key is partially known. Under simplifying assumptions, we derive that the lifetime is linearly dependent on the length of the authentication key. Experimental results that support the theoretical results are also presented.

    Delarbeten
    1. Special Properties of Strongly Universal2 Hash Functions Important in Quantum Cryptography
    Öppna denna publikation i ny flik eller fönster >>Special Properties of Strongly Universal2 Hash Functions Important in Quantum Cryptography
    2009 (Engelska)Ingår i: AIP Conference Proceedings, ISSN 0094-243X, Foundations of Probability and Physics—5, Växjö, augusti 2008, New York: American Institute of Physics , 2009, Vol. 1101, s. 289-293Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Secure message authentication is an important part of Quantum Key Distribution. In this paper we analyze special properties of a Strongly Universal2 hash function family, an understanding of which is important in the security analysis of the authentication used in Quantum Cryptography. We answer the following question: How much of Alices message does Eve need to influence so that the message along with its tag will give her enough information to create the correct tag for her message?

    Ort, förlag, år, upplaga, sidor
    New York: American Institute of Physics, 2009
    Nyckelord
    Quantum cryptography, Quantum theory, Probability
    Nationell ämneskategori
    Matematik
    Identifikatorer
    urn:nbn:se:liu:diva-18738 (URN)10.1063/1.3109951 (DOI)
    Konferens
    Foundations of Probability and Physics—5, Växjö, augusti 2008
    Projekt
    ICG QC
    Tillgänglig från: 2009-06-03 Skapad: 2009-06-03 Senast uppdaterad: 2016-08-31
    2. Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"
    Öppna denna publikation i ny flik eller fönster >>Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"
    2009 (Engelska)Ingår i: International Journal of Quantum Information, ISSN 0219-7499, Vol. 7, nr 5, s. 1047-1052Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In this paper, we review and comment on "A novel protocol-authentication algorithm ruling out a man-in-the-middle attack in quantum cryptography" [M. Peev et al., Int. J. Quant. Inf. 3 (2005) 225]. In particular, we point out that the proposed primitive is not secure when used in a generic protocol, and needs additional authenticating properties of the surrounding quantum-cryptographic protocol.

    Nyckelord
    Quantum cryptography, quantum key distribution, authentication
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-20405 (URN)10.1142/S0219749909005754 (DOI)
    Projekt
    ICG QC
    Tillgänglig från: 2009-09-08 Skapad: 2009-09-07 Senast uppdaterad: 2019-08-15Bibliografiskt granskad
    Ladda ner fulltext (pdf)
    Weaknesses of Authentication inQuantum Cryptography and Strongly Universal Hash Functions
    Ladda ner (pdf)
    Cover
  • 264.
    Abidin, Aysajan
    et al.
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Larsson, Jan-Åke
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Direct proof of security of Wegman-Carter authentication with partially known key2014Ingår i: Quantum Information Processing, ISSN 1570-0755, E-ISSN 1573-1332, Vol. 13, nr 10, s. 2155-2170Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Information-theoretically secure (ITS) authentication is needed in Quantum Key Distribution (QKD). In this paper, we study security of an ITS authentication scheme proposed by Wegman& Carter, in the case of partially known authentication key. This scheme uses a new authentication key in each authentication attempt, to select a hash function from an Almost Strongly Universal2 hash function family. The partial knowledge of the attacker is measured as the trace distance between the authentication key distribution and the uniform distribution; this is the usual measure in QKD. We provide direct proofs of security of the scheme, when using partially known key, first in the information-theoretic setting and then in terms of witness indistinguishability as used in the Universal Composability (UC) framework. We find that if the authentication procedure has a failure probability ε and the authentication key has an ε´ trace distance to the uniform, then under ITS, the adversary’s success probability conditioned on an authentic message-tag pair is only bounded by ε +|Ƭ|ε´, where |Ƭ| is the size of the set of tags. Furthermore, the trace distance between the authentication key distribution and the uniform increases to |Ƭ|ε´ after having seen an authentic message-tag pair. Despite this, we are able to prove directly that the authenticated channel is indistinguishable from an (ideal) authentic channel (the desired functionality), except with probability less than ε + ε´. This proves that the scheme is (ε + ε´)-UC-secure, without using the composability theorem.

    Ladda ner fulltext (pdf)
    fulltext
  • 265.
    Abidin, Aysajan
    et al.
    Linköpings universitet, Institutionen för systemteknik, Informationskodning.
    Larsson, Jan-Åke
    Linköpings universitet, Institutionen för systemteknik, Informationskodning.
    New Universal Hash Functions2012Ingår i: Lecture Notes in Computer Science, Vol. 7242 / [ed] Frederik Armknecht and Stefan Lucks, Springer Berlin Heidelberg , 2012, s. 99-108Konferensbidrag (Refereegranskat)
    Abstract [en]

    Universal hash functions are important building blocks for unconditionally secure message authentication codes. In this paper, we present a new construction of a class of Almost Strongly Universal hash functions with much smaller description (or key) length than the Wegman-Carter construction. Unlike some other constructions, our new construction has a very short key length and a security parameter that is independent of the message length, which makes it suitable for authentication in practical applications such as Quantum Cryptography.

  • 266.
    Abidin, Aysajan
    et al.
    Linköpings universitet, Matematiska institutionen, Tillämpad matematik. Linköpings universitet, Tekniska högskolan.
    Larsson, Jan-Åke
    Linköpings universitet, Matematiska institutionen, Tillämpad matematik. Linköpings universitet, Tekniska högskolan.
    Special Properties of Strongly Universal2 Hash Functions Important in Quantum Cryptography2009Ingår i: AIP Conference Proceedings, ISSN 0094-243X, Foundations of Probability and Physics—5, Växjö, augusti 2008, New York: American Institute of Physics , 2009, Vol. 1101, s. 289-293Konferensbidrag (Refereegranskat)
    Abstract [en]

    Secure message authentication is an important part of Quantum Key Distribution. In this paper we analyze special properties of a Strongly Universal2 hash function family, an understanding of which is important in the security analysis of the authentication used in Quantum Cryptography. We answer the following question: How much of Alices message does Eve need to influence so that the message along with its tag will give her enough information to create the correct tag for her message?

  • 267.
    Abidin, Aysajan
    et al.
    Linköpings universitet, Matematiska institutionen, Tillämpad matematik. Linköpings universitet, Tekniska högskolan.
    Larsson, Jan-Åke
    Linköpings universitet, Matematiska institutionen, Tillämpad matematik. Linköpings universitet, Tekniska högskolan.
    Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"2009Ingår i: International Journal of Quantum Information, ISSN 0219-7499, Vol. 7, nr 5, s. 1047-1052Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we review and comment on "A novel protocol-authentication algorithm ruling out a man-in-the-middle attack in quantum cryptography" [M. Peev et al., Int. J. Quant. Inf. 3 (2005) 225]. In particular, we point out that the proposed primitive is not secure when used in a generic protocol, and needs additional authenticating properties of the surrounding quantum-cryptographic protocol.

    Ladda ner fulltext (pdf)
    Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"
  • 268.
    Abidin, Aysajan
    et al.
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Pacher, Christoph
    Austrian Institute of Technology, Austria.
    Lorünser, Thomas
    Austrian Institute of Technology, Austria.
    Larsson, Jan-Åke
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska högskolan.
    Peev, Momtchil
    Austrian Institute of Technology, Austria.
    Quantum cryptography and authentication with low key-consumption2011Ingår i: Proceedings of SPIE - The International Society for Optical Engineering, 2011, s. 818916-Konferensbidrag (Refereegranskat)
    Abstract [en]

    Quantum Key Distribution (QKD - also referred to as Quantum Cryptography) is a technique for secret key agreement. It has been shown that QKD rigged with Information-Theoretic Secure (ITS) authentication (using secret key) of the classical messages transmitted during the key distribution protocol is also ITS. Note, QKD without any authentication can trivially be broken by man-in-the-middle attacks. Here, we study an authentication method that was originally proposed because of its low key consumption; a two-step authentication that uses a publicly known hash function, followed by a secret strongly universal2 hash function, which is exchanged each round. This two-step authentication is not information-theoretically secure but it was argued that nevertheless it does not compromise the security of QKD. In the current contribution we study intrinsic weaknesses of this approach under the common assumption that the QKD adversary has access to unlimited resources including quantum memories. We consider one implementation of Quantum Cryptographic protocols that use such authentication and demonstrate an attack that fully extract the secret key. Even including the final key from the protocol in the authentication does not rule out the possibility of these attacks. To rectify the situation, we propose a countermeasure that, while not informationtheoretically secure, restores the need for very large computing power for the attack to work. Finally, we specify conditions that must be satisfied by the two-step authentication in order to restore informationtheoretic security.

  • 269.
    Abildgaard, Lars
    et al.
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Anestesiologi. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, Anestesi.
    Aaro, Stig
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för nervsystem och rörelseorgan, Ortopedi och Idrottsmedicin.
    Lisander, Björn
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Anestesiologi. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, Anestesi.
    Limited effectiveness of intraoperative autotransfusion in major back surgery2001Ingår i: European Journal of Anaesthesiology, ISSN 0265-0215, E-ISSN 1365-2346, Vol. 18, nr 12, s. 823-828Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background and objective: The efficiency of intraoperative autotransfusion in scoliosis surgery is poorly known but needs to be evaluated, not least because of the large blood losses in these patients. This is a retrospective analysis of transfusion requirements of 43 such patients. Methods: Records from 43 patients were studied. During surgery, the shed blood was salvaged and washed in an autotransfusion device (AT1000 Auto-transfusion Unit«) and a suspension of red cells was reinfused. Results: Fifty-eight per cent of the intraoperative blood loss was salvaged. The total blood loss during the patients' hospital stay was calculated from the haemoglobin balance, 24% of this loss was salvaged by the device. Moreover, 36 of the patients needed allogeneic blood transfusion. Conclusion: The efficiency of the autotransfusion device was relatively low in relation to the total extravasation, mainly because the postoperative blood loss is substantial.

  • 270.
    Abioye, Ajibola I.
    et al.
    Brown Univ, RI 02912 USA.
    McDonald, Emily A.
    Brown Univ, RI 02912 USA.
    Park, Sangshin
    Brown Univ, RI 02912 USA; Univ Seoul, South Korea.
    Joshi, Ayush
    Brown Univ, RI 02912 USA.
    Kurtis, Jonathan D.
    Brown Univ, RI 02912 USA.
    Wu, Hannah
    Brown Univ, RI 02912 USA.
    Pond-Tor, Sunthorn
    Brown Univ, RI 02912 USA.
    Sharma, Surendra
    Brown Univ, RI 02912 USA; Women and Infants Hosp Rhode Isl, RI 02908 USA.
    Ernerudh, Jan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk immunologi och transfusionsmedicin.
    Baltazar, Palmera
    Remedios Trinidad Romualdez Hosp, Philippines.
    Acosta, Luz P.
    Res Inst Trop Med, Philippines.
    Olveda, Remigio M.
    Res Inst Trop Med, Philippines.
    Tallo, Veronica
    Res Inst Trop Med, Philippines.
    Friedman, Jennifer F.
    Brown Univ, RI 02912 USA.
    Maternal, placental and cord blood cytokines and the risk of adverse birth outcomes among pregnant women infected with Schistosoma japonicum in the Philippines2019Ingår i: PLoS Neglected Tropical Diseases, ISSN 1935-2727, E-ISSN 1935-2735, Vol. 13, nr 6, artikel-id e0007371Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background The objectives of this study were to 1) evaluate the influence of treatment with praziquantel on the inflammatory milieu in maternal, placental, and cord blood, 2) assess the extent to which proinflammatory signatures in placental and cord blood impacts birth outcomes, and 3) evaluate the impact of other helminths on the inflammatory micro environment. Methods/Findings This was a secondary analysis of samples from 369 mother-infant pairs participating in a randomized controlled trial of praziquantel given at 12-16 weeks gestation. We performed regression analysis to address our study objectives. In maternal peripheral blood, the concentrations of CXCL8, and TNF receptor I and II decreased from 12 to 32 weeks gestation, while IL-13 increased. Praziquantel treatment did not significantly alter the trajectory of the concentration of any of the cytokines examined. Hookworm infection was associated with elevated placental IL-1, CXCL8 and IFN-gamma. The risk of small-for-gestational age increased with elevated IL-6, IL-10, and CXCL8 in cord blood. The risk of prematurity was increased when cord blood sTNFRI and placental IL-5 were elevated. Conclusions Our study suggests that fetal cytokines, which may be related to infectious disease exposures, contribute to poor intrauterine growth. Additionally, hookworm infection influences cytokine concentrations at the maternal-fetal interface. Clinical Trial Registry number and website ClinicalTrials.gov (NCT00486863). Author summary Schistosomiasis is one of the most prevalent parasitic tropical diseases, and it is primarily treated with the drug praziquantel. This study examined the effects of praziquantel treatment for schistosomiasis and the presence of geohelminth infections during pregnancy on cytokines in maternal, placental, and cord blood, and examined the effects of pro-inflammatory signatures at the maternal-fetal interface on perinatal outcomes. We analyzed the data of 369 mother-infant pairs obtained from a randomized controlled trial of praziquantel given at 12-16 weeks gestation. Praziquantel treatment did not significantly alter the trajectory of the concentration of any of the cytokines examined. Elevated levels of both Th1 and Th2 cytokines were associated with the risk of adverse perinatal outcomes (small-for-gestational age and prematurity). Hookworm coinfection at 12 weeks gestation was, however, related to elevated levels of certain cytokines in the placenta (IL-1, IL-5, CXCL8 and IFN-gamma).

    Ladda ner fulltext (pdf)
    fulltext
  • 271.
    Abioye, Ajibola I.
    et al.
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Park, Sangshin
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Ripp, Kelsey
    Brown Univ, RI 02912 USA.
    McDonald, Emily A.
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Kurtis, Jonathan D.
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Wu, Hannah
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Pond-Tor, Sunthorn
    Rhode Isl Hosp, RI USA.
    Sharma, Surendra
    Brown Univ, RI 02912 USA; Women and Infants Hosp Rhode Isl, RI 02908 USA.
    Ernerudh, Jan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk immunologi och transfusionsmedicin.
    Baltazar, Palmera
    Res Inst Trop Med, Philippines; Remedios Trinidad Romualdez Hosp, Philippines.
    Acosta, Luz P.
    Res Inst Trop Med, Philippines.
    Olveda, Remigio M.
    Res Inst Trop Med, Philippines.
    Tallo, Veronica
    Res Inst Trop Med, Philippines.
    Friedman, Jennifer F.
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Anemia of Inflammation during Human Pregnancy Does Not Affect Newborn Iron Endowment2018Ingår i: Journal of Nutrition, ISSN 0022-3166, E-ISSN 1541-6100, Vol. 148, nr 3, s. 427-436Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: To our knowledge, no studies have addressed whether maternal anemia of inflammation (AI) affects newborn iron status, and few have addressed risk factors for specific etiologies of maternal anemia. Objectives: The study aims were to evaluate 1) the contribution of AI and iron deficiency anemia (IDA) to newborn iron endowment, 2) hepcidin as a biomarker to distinguish AI from IDA among pregnant women, and 3) risk factors for specific etiologies of maternal anemia. Methods: We measured hematologic biomarkers in maternal blood at 12 and 32 wk of gestation and in cord blood from a randomized trial of praziquantel in 358 pregnant women with Schistosoma japonicum in The Philippines. IDA was defined as anemia with serum ferritin amp;lt; 30 ng/mL and non-IDA (NIDA), largely due to AI, as anemia with ferritin amp;gt;= 30 ng/mL. We identified cutoffs for biomarkers to distinguish IDA from NIDA by using area under the curve (AUC) analyses and examined the impact of different causes of anemia on newborn iron status (primary outcome) by using multivariate regression modeling. Results: Of the 358 mothers, 38% (n = 136) had IDA and 9% (n = 32) had NIDA at 32 wk of gestation. At 32 wk of gestation, serum hepcidin performed better than soluble transferrin receptor (sTfR) in identifying women with NIDA compared with the rest of the cohort (AUCs: 0.75 and 0.70, respectively) and in identifying women with NIDA among women with anemia (0.73 and 0.72, respectively). The cutoff that optimally distinguished women with NIDA from women with IDA in our cohort was 6.1 mu g/L. Maternal IDA, but not NIDA, was associated with significantly lower newborn ferritin (114.4 ng/mL compared with 148.4 mu g/L; P = 0.042). Conclusions: Hepcidin performed better than sTfR in identifying pregnant women with NIDA, but its cost may limit its use. Maternal IDA, but not NIDA, is associated with decreased newborn iron stores, emphasizing the need to identify this cause and provide iron therapy.

  • 272.
    Abiyev, Rahib H.
    et al.
    Near East Univ, Turkiye.
    Altabel, Mohamad Ziad
    Near East Univ, Turkiye.
    Darwish, Manal
    Near East Univ, Turkiye.
    Helwan, Abedelkader
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Linköpings universitet, Medicinska fakulteten.
    A Multimodal Transformer Model for Recognition of Images from Complex Laparoscopic Surgical Videos2024Ingår i: Diagnostics, ISSN 2075-4418, Vol. 14, nr 7, artikel-id 681Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The determination of the potential role and advantages of artificial intelligence-based models in the field of surgery remains uncertain. This research marks an initial stride towards creating a multimodal model, inspired by the Video-Audio-Text Transformer, that aims to reduce negative occurrences and enhance patient safety. The model employs text and image embedding state-of-the-art models (ViT and BERT) to assess their efficacy in extracting the hidden and distinct features from the surgery video frames. These features are then used as inputs for convolution-free Transformer architectures to extract comprehensive multidimensional representations. A joint space is then used to combine the text and image features extracted from both Transformer encoders. This joint space ensures that the relationships between the different modalities are preserved during the combination process. The entire model was trained and tested on laparoscopic cholecystectomy (LC) videos encompassing various levels of complexity. Experimentally, a mean accuracy of 91.0%, a precision of 81%, and a recall of 83% were reached by the model when tested on 30 videos out of 80 from the Cholec80 dataset.

  • 273.
    Abjanbekov, Aidyn
    et al.
    Linköpings universitet, Ekonomiska institutionen.
    Alvarez Padilla, Ana Elena
    Linköpings universitet, Ekonomiska institutionen.
    From Knowledge Transfer to Knowledge Translation: Case Study of a Telecom Consultancy2004Självständigt arbete på avancerad nivå (magisterexamen)Studentuppsats
    Abstract [en]

    Background: In today’s highly competitive business environment, knowledge is viewed as a key strategic resource. The privatization process of telecom operators in different countries created a demand in telecom management skills, and Swedish companies like Swedtel AB became involved in exporting and transferring their knowledge and management skills.

    Purpose: The purpose of this thesis paper is to identify all stages (from origins to final destination) of the Knowledge Transfer process and to contribute to the understanding about the mechanism of Knowledge Transfer between organizations.

    Scope: This research is limited to the investigation of the transfer process of strategic management knowledge from consulting company Swedtel AB to privatized telecom companies in Lithuania (Lietuvos Telekomas) and Nicaragua (Enitel).

    Results: Theoretical model of Knowledge Transfer was identified and tested. The model of this research was only partially supported: processes were identified in practice as described by the theory, however model required modifications in order to better reflect the reality.

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    FULLTEXT01
  • 274.
    Ablahad, Marlen
    Linköpings universitet, Institutionen för religion och kultur.
    Bära Sorg Föra Liv: En studie om begravningsritualer bland syrianer/assyrier i hemlandet och i Sverige.2005Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [en]

    This essay describes the phases of funeral rituals between the Syrian/Assyrian, and compares the homeland with Sweden. It describes the stage of rituals according to Victor Turner schema of separation, margin or limin, and aggregation. The rituals religious significance agrees with Clifford Geertz’s theory about the importance of religious beliefs for the human being

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 275.
    Ablieieva, Iryna
    et al.
    Sumy State Department of Ecology and Environmental Protection Technologies, Sumy State University, Sumy, Ukraine.
    Berezhna, Iryna
    Sumy State Department of Ecology and Environmental Protection Technologies, Sumy State University, Sumy, Ukraine.
    Berezhnyi, Dmytrii
    Sumy State Department of Ecology and Environmental Protection Technologies, Sumy State University, Sumy, Ukraine.
    Enrich Prast, Alex
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten.
    Geletukha, Georgiy
    Institute of Engineering Thermophysics of the National Academy of Sciences of Ukraine, Kyiv, Ukraine.
    Lutsenko, Serhii
    Sumy State Department of Ecology and Environmental Protection Technologies, Sumy State University, Sumy, Ukraine.
    Yanchenko, Ilona
    Sumy State Department of Ecology and Environmental Protection Technologies, Sumy State University, Sumy, Ukraine.
    Carraro, Giacomo
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten.
    Technologies for Environmental Safety Application of Digestate as Biofertilizer2022Ingår i: Ecological Engineering & Environmental Technology, ISSN 2719-7050, Vol. 23, nr 3, s. 106-119Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of the paper is to determine the environmentally safe and economically feasible technology of biofertilizer production from the digestate including dewatering process. Methodological basis is based on the systematic approach to the determination of factors effected on the distribution of nutrients and pollutants between liquidand solid fractions after digestate separation. We studied modern technologies aimed at dewatering the digestateand reduction of its volume, showed their effectiveness. These technologies allow expanding the opportunities forcommercialization of the digestate, increasing the cost of its transportation and application to the soil instead ofcomplex fertilizers, using some valuable products. The results of the study showed that the ecological quality ofthe digestate is the highest as well as co-digested thermally pre-treated feedstock is used for solid-liquid separationin centrifuge with polymer addition as post-treatment approach to the flocculation. In order to increase efficiencyof biofertilizer application the technological scheme of production process of granular fertilizers from digestatewas proposed. Special feature of this scheme is in the use of phosphogypsum binder for the production of organomineral fertilizer that contributes phosphogypsum recycling in the waste management system.

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  • 276.
    Ablieieva, Iryna
    et al.
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Biogas Solutions Research Center. Sumy State University, Ukraine.
    Chernysh, Yelizaveta
    Sumy State University, Ukraine; Czech University of Life Sciences Prague, Czech Republic.
    Chubur, Viktoriia
    Sumy State University, Ukraine; Czech University of Life Sciences Prague, Czech Republic.
    Skvortsova, Polina
    Sumy State University, Ukraine.
    Roubik, Hynek
    Czech University of Life Sciences Prague, Czech Republic.
    Biopotential of Agricultural Waste: Production of Biofertilizers and Biofuels2022Ingår i: 22nd International Multidisciplinary Scientific Geoconference: Energy and Clean Technologies, SGEM 2022, Vienna, 6 December 2022 - 8 December 2022 / [ed] Trofymchuk O., Rivza B., Vienna, 2022, Vol. 22, 4.2, s. 39-47Konferensbidrag (Refereegranskat)
    Abstract [en]

    This article is focused on performing a SWOT analysis of agricultural waste management methods. This approach can be applied in the biogas technology strategic planning process in Ukraine, which can solve the issue of implementation of environmental guidelines for the development of biofuels and biofertilizers. The main factors that determine how digestate is used are its quality, local conditions, regulations, and documents. Fertilizing fields with digestate provides many advantages, for example: reduced demand for plant protection products, reduction of unpleasant odor, and destruction of possible pathogens. The strengths and weaknesses of the implementation of biogas plants in Ukraine have been identified, and opportunities and threats have been considered. In general, the introduction of biogas technology is a very promising solution for the agricultural sector. Taking into account that a biogas plant is considered a potentially hazardous object for workers, it is necessary to constantly monitor the parameters of reactor operation in order to ensure the technological and environmental safety of the engineering facilities. For Ukraine, there is a shortage of specialists to set up an effective operation of biogas equipment and bring it to the industrial scale. It is necessary to consult with medium and small farms interested in the feasibility study and implementation of biogas technologies. 

  • 277.
    Ablieieva, Iryna
    et al.
    Sumy State University, Sumy, Ukraine.
    Geletukha, Georgii
    Institute of Engineering Thermophysics of the National Academy of Sciences of Ukraine; Marii Kapnist Street, 03057, Kyiv, Ukraine.
    Kucheruk, Petro
    Institute of Engineering Thermophysics of the National Academy of Sciences of Ukraine; Marii Kapnist Street, 03057, Kyiv, Ukraine.
    Enrich Prast, Alex
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten.
    Carraro, Giacomo
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten.
    Berezhna, Iryna
    Sumy State University, Sumy, Ukraine.
    Berezhnyi, Dmytrii
    Sumy State University, Sumy, Ukraine.
    Digestate Potential to Substitute Mineral Fertilizers: Engineering Approaches2022Ingår i: Journal of Engineering Sciences, ISSN 2312-2498, Vol. 9, nr 1, s. H1-H10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The study aims to define the potential and technological aspects of the digestate treatment for its application as a biofertilizer. Life cycle assessment methodology was used in terms of digestate quality management. The potential of nutrients, organic carbon, and useful microelements in the digestate allows for its consideration as a mineral fertilizer substitute and soil improver. The valorization of digestate as fertilizer requires quality management and quality control. Based on the research focus, the successful soil application of digestate post-treatment technologies was analyzed. Among the different commercial options for digestate treatment and nutrient recovery, the most relevant are drying, struvite precipitation, stripping, evaporation, and membranes technology. Comparing the physical and chemical properties of the whole digestate, separated liquid, and solid liquor fractions showed that in the case of soil application of granular fertilizer, nutrients from the digestate are released more slowly than digestate application without granulation. However, realizing this potential in an economically feasible way requires improving the quality of digestate products through appropriate technologies and quality control of digestate products. To support the manufacture of quality digestate across Europe, the European Compost Network developed a concept for a pan-European quality assurance scheme.

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  • 278.
    Ablieieva, Iryna
    et al.
    Sumy State Univ, Sumy, Ukraine.
    Plyatsuk, Leonid
    Sumy State Univ, Sumy, Ukraine.
    Burla, Oksana
    Sumy State Univ, Sumy, Ukraine.
    Chekh, Oleh
    Sumy State Univ, Sumy, Ukraine.
    Enrich-Prast, Alex
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten.
    Theoretical Substantiation of Mathematical Models of Oil Filtration Through a Porous Medium2022Ingår i: Advanced Manufacturing Processes III , Interpartner-2021 / [ed] Tonkonogyi, V., Ivanov, V., Trojanowska, J., Oborskyi, G., Pavlenko, I, Heidelberg, Germany: Springer, 2022, s. 571-581Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper focuses on determining the influence of soil, oil, and environmental factors on the process of oil filtration in a porous medium such as soil. Mathematical modeling of the oil geofiltration process based on classical and modified regularities makes it possible to solve a significant environmental problem associated with predicting the pollution zone due to accidental oil spills. The research methodology is based on the substantiation of theoretical models of oil filtration through porous media, methods for the numerical solution of equations, and computer visualization (ANSYS CFX software). Experimental data supported the verification of the adequacy of the models. Based on obtained results, it was found that all oil flowed into well-permeable sand at a speed of approximately 4-10 -4 m/h. The developed model of the stochastic process of petroleum hydrocarbons geofiltration involved obtaining the output as dependent variables, contamination level, contamination depth, and oil spot borders. Numerical solution and visualization using computer simulation showed the distribution of oil hydrocarbons in the soil in vertical and horizontal directions. The mathematical model allowed to predict the formation of the pollution front and assess the contaminated zone's size.

  • 279.
    Abo Al Ahad, George
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Nationalekonomi. Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik.
    Gerzic, Denis
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Nationalekonomi. Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik.
    A Study on the Low Volatility Anomaly in the Swedish Stock Exchange Market: Modern Portfolio Theory2017Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This study investigates, with a critical approach, if portfolios consisting of high beta stocks yields more than portfolios consisting of low beta stocks in the Swedish stock exchange market. The chosen period is 1999-2016, covering both the DotCom Bubble and the financial crisis of 2008. We also investigate if the Capital Asset Pricing Model is valid by doing a test similar to Fama and Macbeth’s of 1973.

    Based on earlier studies in the field and our own study we come to the conclusion that high beta stocks does not outperform low beta stocks in the Swedish stock market 1999-2016. We believe that this relationship arises from inefficiencies in the market and irrational investing. By doing this study we observe that, the use of beta as the only risk factor for explaining expected returns on stocks or portfolios is not correct.

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    fulltext
  • 280.
    Abo Al Ahad, George
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Produktionsekonomi.
    Salami, Abbas
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Produktionsekonomi.
    Machine Learning for Market Prediction: Soft Margin Classifiers for Predicting the Sign of Return on Financial Assets2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Forecasting procedures have found applications in a wide variety of areas within finance and have further shown to be one of the most challenging areas of finance. Having an immense variety of economic data, stakeholders aim to understand the current and future state of the market. Since it is hard for a human to make sense out of large amounts of data, different modeling techniques have been applied to extract useful information from financial databases, where machine learning techniques are among the most recent modeling techniques. Binary classifiers such as Support Vector Machines (SVMs) have to some extent been used for this purpose where extensions of the algorithm have been developed with increased prediction performance as the main goal. The objective of this study has been to develop a process for improving the performance when predicting the sign of return of financial time series with soft margin classifiers.

    An analysis regarding the algorithms is presented in this study followed by a description of the methodology that has been utilized. The developed process containing some of the presented soft margin classifiers, and other aspects of kernel methods such as Multiple Kernel Learning have shown pleasant results over the long term, in which the capability of capturing different market conditions have been shown to improve with the incorporation of different models and kernels, instead of only a single one. However, the results are mostly congruent with earlier studies in this field. Furthermore, two research questions have been answered where the complexity regarding the kernel functions that are used by the SVM have been studied and the robustness of the process as a whole. Complexity refers to achieving more complex feature maps through combining kernels by either adding, multiplying or functionally transforming them. It is not concluded that an increased complexity leads to a consistent improvement, however, the combined kernel function is superior during some of the periods of the time series used in this thesis for the individual models. The robustness has been investigated for different signal-to-noise ratio where it has been observed that windows with previously poor performance are more exposed to noise impact.

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    ML for Market Predictions
  • 281.
    Aboelnaga, Ahmed
    et al.
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Elmasry, Moustafa
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för Kirurgi, Ortopedi och Onkologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Hand- och plastikkirurgiska kliniken US. Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Adly, Osama A.
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Elbadawy, Mohamed A.
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Abbas, Ashraf H.
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Abdelrahman, Islam
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för Kirurgi, Ortopedi och Onkologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Hand- och plastikkirurgiska kliniken US. Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Salah, Omar
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Steinvall, Ingrid
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för Kirurgi, Ortopedi och Onkologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Hand- och plastikkirurgiska kliniken US.
    Microbial cellulose dressing compared with silver sulphadiazine for the treatment of partial thickness burns: A prospective, randomised, clinical trial2018Ingår i: Burns, ISSN 0305-4179, E-ISSN 1879-1409, Vol. 44, nr 8, s. 1982-1988Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background

    The current treatment for partial thickness burns at the trial site is silver sulphadiazine, as it minimises bacterial colonisation of wounds. Its deleterious effect on wound healing, together with the need for repeated, often painful, procedures, has brought about the search for a better treatment. Microbial cellulose has shown promising results that avoid these disadvantages. The aim of this study was therefore to compare microbial cellulose with silver sulphadiazine as a dressing for partial thickness burns.

    Method

    All patients who presented with partial thickness (superficial and deep dermal) burns from October 2014 to October 2016 were screened for this randomised clinical trial. Twenty patients were included in each group: the cellulose group was treated with microbial cellulose sheets and the control group with silver sulphadiazine cream 10 mg/g. The wound was evaluated every third day. Pain was assessed using the Face, Legs, Activity, Cry, Consolability (FLACC) scale during and after each procedure. Other variables recorded were age, sex, percentage total body surface area burned (TBSA%), clinical signs of infection, time for epithelialisation and hospital stay. Linear multivariable regression was used to analyse the significance of differences between the treatment groups by adjusting for the size and depth of the burn, and the patient’s age.

    Results

    Median TBSA% was 9% (IQR 5.5–12.5). The median number of dressing changes was 1 (IQR 1–2) in the cellulose group, which was lower than that in the control group (median 9.5, IQR 6–16) (p < 0.001). Multivariable regression analysis showed that the group treated with microbial cellulose spent 6.3 (95% CI 0.2–12.5) fewer days in hospital (p = 0.04), had a mean score that was 3.4 (95% CI 2.5–4.3) points lower during wound care (p < 0.001), and 2.2 (95% CI 1.6–2.7) afterwards (p < 0.001). Epithelialisation was quicker, but not significantly so.

    Conclusion

    These results suggest that the microbial cellulose dressing is a better first choice for treatment of partial thickness burns than silver sulphadiazine cream. Fewer dressings of the wound were done and, combined with the low pain scores, this is good for both the patients and the health care system. The differences in randomisation of the area of burns is, however, a concern that needs to be included in the interpretation of the results.

  • 282. Abom, A.E.
    et al.
    Comini, E.
    Dipto. di Chim. e Fis. dei Materaili, INFM, Università di Brescia, Via Valotti 9, I-251 33 Brescia, Italy.
    Sberveglieri, G.
    Dipto. di Chim. e Fis. dei Materaili, INFM, Università di Brescia, Via Valotti 9, I-251 33 Brescia, Italy.
    Finnegan, N.
    Ctr. for Microanalysis of Materials, Frederick Seitz Mat. Res. Laboratory, University of Illinois, Urbana, IL 61801, United States.
    Petrov, I.
    Ctr. for Microanalysis of Materials, Frederick Seitz Mat. Res. Laboratory, University of Illinois, Urbana, IL 61801, United States.
    Hultman, Lars
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik.
    Erikssion, M.
    Experimental evidence for a dissociation mechanism in NH3 detection with MIS field-effect devices2003Ingår i: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 89, nr 1-2Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The gas response mechanism of ammonia detection with Pt-based metal-insulator-semiconductor (MIS) field-effect sensors was investigated. An experimental model system was designed which compares the responses of thick continuous Pt layers with controlled morphology and surface chemical composition, with the response of thin, discontinuous layers. The surface of a thick, continuous sputter-deposited Pt film is modified, either by (i) the deposition of a thin SiO2 overlayer, (ii) reactive sputter deposition of PtOx, or (iii) co-deposition of Pt with SiO2 in Ar + O2 atmospheres. We show that the ammonia response is caused by the formation of atomic hydrogen through the dissociation of NH3 at temperatures <200 °C. It is found that the modified surfaces exhibit increased ammonia selectivity compared to a pure Pt film. Results from this work indicate that the reason for the changed selectivity is the appearance of an oxidized PtOx phase or triple phase boundaries between Pt, SiO2 and the ambient gas, rather than for solely morphological reasons. © 2002 Elsevier Science B.V. All rights reserved.

  • 283. Abom, A.E.
    et al.
    Comini, E.
    Sberveglieri, G.
    Hultman, Lars
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik.
    Eriksson, Mats
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik.
    Thin oxide films as surface modifiers of MIS field effect gas sensors2002Ingår i: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 85, nr 1-2, s. 109-119Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The catalytic activity at the surface of Pt based MIS field effect gas sensors is modified by the deposition of thin films of SnO2, Al2O3 and SiO2, grown by reactive sputtering. It is found that a very thin layer (<10 nm) of SiO2 and SnO2 changes the catalytic activity towards higher NH3 selectivity, but with thicker films the sensor response vanishes. Since the response mechanism for these sensors is dependent on dissociation of molecules, it is likely that at low temperatures (140 °C), neither dissociation on nor transport/diffusion through the thicker films takes place. However, with Pt in conjunction with SiO2 or SnO2, the surface reactions will be altered, with enhanced NH3 selectivity as a result. A thin film of Al2O3, on the other hand, has a much smaller influence on the gas response to the test gases used in this work. Furthermore the sputtering process is found to strongly influence the sensor responses, and specifically reduce the sensitivity of the sensor. A thin intermediate layer of evaporated Pt does not completely protect the underlying structure from sputter induced damage. © 2002 Elsevier Science B.V. All rights reserved.

  • 284. Abom, A.E.
    et al.
    Haasch, R.T.
    Frederick Seitz Mat. Res. Laboratory, University of Illinois, Urbana, IL 61801, United States.
    Hellgren, N.
    Frederick Seitz Mat. Res. Laboratory, University of Illinois, Urbana, IL 61801, United States.
    Finnegan, N.
    Frederick Seitz Mat. Res. Laboratory, University of Illinois, Urbana, IL 61801, United States.
    Hultman, Lars
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik.
    Eriksson, Mats
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik.
    Characterization of the metal-insulator interface of field-effect chemical sensors2003Ingår i: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 93, nr 12, s. 9760-9768Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The metal-insulator interface of hydrogen-sensitive metal-insulator-semiconductor capacitors, with SiO2 as the insulator and Pt as the metal contact, was discussed. It was found that the difference in hydrogen response between differently prepared devices was explained by a difference in concentration of available adsorption sites. The analysis showed that the concentration of Pt atoms in contact with the oxide affected both the hydrogen response and the metal-oxide adhesion.

  • 285. Abom, A.E.
    et al.
    Persson, Per
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik.
    Hultman, Lars
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik.
    Eriksson, Mats
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik.
    Influence of gate metal film growth parameters on the properties of gas sensitive field-effect devices2002Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 409, nr 2, s. 233-242Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Thin films of Pt have been grown as gate metals on the oxide surface of gas sensitive field-effect devices. Both electron beam evaporation and dc magnetron sputtering has been used. The energy of the impinging Pt atoms, the substrate temperature and the thickness of the Pt film were used as parameters in this study. The influence of the growth parameters on the gas response has been investigated and compared with the properties of the films, studied by transmission electron microscopy, Auger electron spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. The conditions during growth of the Pt film are found to have a large impact on the properties of the device. As expected, crystallinity, morphology and the metal/substrate interfacial structure are also affected by processing parameters. Three different growth processes stand out as the most promising from gas sensor considerations, namely room temperature evaporation, sputtering at high pressures and sputtering at high temperatures. The correlation between gas responses and properties of the gas sensitive layer is discussed. © 2002 Elsevier Science B.V. All rights reserved.

  • 286.
    Abongo, D. A.
    et al.
    University of Nairobi, Kenya.
    Wandiga, S. O.
    University of Nairobi, Kenya.
    Jumba, I. O.
    University of Nairobi, Kenya.
    Van den Brink, P. J.
    University of Wageningen and Research Centre, Netherlands.
    Naziriwo, B. B.
    Makerere University, Uganda.
    Madadi, V. O.
    University of Nairobi, Kenya.
    Wafula, G. A.
    University of Nairobi, Kenya.
    Nkedi-Kizza, P.
    University of Florida, FL USA.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten. North West University, South Africa.
    Occurrence, abundance and distribution of benthic macroinvertebrates in the Nyando River catchment, Kenya2015Ingår i: African Journal of Aquatic Science, ISSN 1608-5914, E-ISSN 1727-9364, Vol. 40, nr 4, s. 373-392Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A baseline study was conducted of the occurrence of macroinvertebrates at 26 sites in the Nyando River catchment in 2005-2006. A total of 13 orders and 16 families of Arthropoda, Mollusca, Platyhelminthes and Annelida were collected, with the order Ephemeroptera being most abundant in the up- and mid-stream reaches, followed by Hemiptera and Plecoptera respectively. The downstream sections of the river were dominated by Hirudinea and tubificids, as the water quality deteriorated mainly due to local land use, raw sewage effluent discharge and annual floods. Insects and annelids were the main invertebrates found and the extent of pollution increased from mid-section (Site 15) downwards as the river flowed into the Winam Gulf. Stringent management measures are required to safeguard the environment and ecosystems of Lake Victoria.

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    fulltext
  • 287.
    Abong'o, Deborah
    et al.
    University of Nairobi, Kenya.
    Wandiga, Shem
    University of Nairobi, Kenya.
    Jumba, Isaac
    University of Nairobi, Kenya.
    Madadi, Vincent
    University of Nairobi, Kenya.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Impacts of pesticides on human health and environment in the River Nyando catchment, Kenya2014Ingår i: International Journal of Humanities, Arts, Medicine and Sciences, ISSN 2348-0521, Vol. 2, nr 3, s. 1-14Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    The population of the River Nyando catchment largely relies on rain fed agriculture for their subsistence.

    Important crops grown include cereals, cash crops fruits and vegetables. Farming is one of the contributors of pollution to Lake Victoria. Organophosphates and other banned organochlorine pesticides such as lindane, aldrin and dieldrin were used by farmers. The pesticides transport was by storm water run-off and air drift into the lake. Environmental risk assessment background information was collected through questionnaire and interviews of farmers to determine knowledge and safe use of pesticides. Fourteen pesticides were identified as commonly used of which four are toxic to bees and five to birds. The farmers identified declines in the number of pollinating insects, the disappearance of Red-billed Oxpecker (Buphagus erythrorthynchus) and wild bird’s fatalities. The general knowledge among farmers about chemicals risks, safety, and chronic illnesses was low. Activities that increases environmental awareness and safety of pesticides should be initiated by the agrochemical firms and government.

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    River Nyando catchment 1
  • 288.
    Abong'o, Deborah
    et al.
    University of Nairobi, Kenya.
    Wandiga, Shem
    University of Nairobi. Kenya.
    Jumba, Isac
    University of Nairobi, Kenya.
    van den Brink, Paul
    Wageningen University, the Netherlands.
    Nazariwo, Betty
    Makerere University, Uganda.
    Madadi, Vincent
    University of Nairobi, Kenya.
    Wafula, Godfrey
    University of Nairobi, Kenya.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten.
    Nkedi-Kizza, Peter
    University of Florida, USA.
    Organochlorine pesticide residue levels in soil from the Nyando River catchment, Kenya2015Ingår i: Africa Journal of Physical Sciences, ISSN 2313-3317, Vol. 2, nr 1, s. 18-32Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Soil samples were collected from six locations representative of the Nyando River catchment area of the Lake Victoria over a period of two years. Sampling was done four times in the year in February, May, September and December 2005 and 2006 in farms where maize, tea, sugar cane, coffee, rice and vegetables have been grown over the years. This coincided with the effects of different seasons and farming activities on residue levels of the pesticides in use. The objective was to investigate levels and distribution of organochlorine pesticides that have either been banned or are restricted for use in Kenya. Organochlorine pesticides investigated were DDT, lindane, aldrin, dieldrin, heptachlor, endrin, endosulfan (both α- and β- isomers and endosulfan sulphate), the sum is called “total” or Σendosulfan and methoxychlor. Prior to the ban or restriction in use, these pesticides had found wide applications in public health for control of disease vectors and in agriculture for control of crop pests. The analysis revealed presence of all the targeted pesticides with the highest mean concentrations for methoxychlor 140 ± 1.5 μg/kg, Σendosulfan (30 ± 2.1 μg/kg), aldrin (18 ± 0.28 μg/kg), respectively. The results show the presence of these pesticides in soils in the basin and this could be impacting negatively on the ecosystem health of the area.

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    fulltext
  • 289.
    Abou Ghayda, Ramy
    et al.
    Case Western Reserve Univ, OH 44106 USA.
    Lee, Keum Hwa
    Yonsei Univ, South Korea.
    Han, Young Joo
    Inje Univ, South Korea.
    Ryu, Seohyun
    Yonsei Univ, South Korea.
    Hong, Sung Hwi
    Yonsei Univ, South Korea.
    Yoon, Sojung
    Yonsei Univ, South Korea.
    Jeong, Gwang Hum
    Gyeongsang Natl Univ, South Korea.
    Yang, Jae Won
    Yonsei Univ, South Korea.
    Lee, Hyo Jeong
    Yonsei Univ, South Korea.
    Lee, Jinhee
    Yonsei Univ, South Korea.
    Lee, Jun Young
    Yonsei Univ, South Korea.
    Effenberger, Maria
    Med Univ Innsbruck, Austria.
    Eisenhut, Michael
    Luton & Dunstable Univ Hosp NHS Fdn Trust, England.
    Kronbichler, Andreas
    Med Univ Innsbruck, Austria.
    Solmi, Marco
    Univ Ottawa, Canada; Ottawa Hosp, Canada; Univ Ottawa, Canada; Univ Ottawa, Canada.
    Li, Han
    Univ Florida, FL USA.
    Jacob, Louis
    Univ Versailles St Quentin En Yvelines, France; CIBERSAM, Spain.
    Koyanagi, Ai
    CIBERSAM, Spain; ICREA, Spain.
    Radua, Joaquim
    Inst Invest Biomed August Pi & Sunyer IDIBAPS, Spain; Kings Coll London, England; Karolinska Inst, Sweden.
    Park, Myung Bae
    Pai Chai Univ, South Korea.
    Aghayeva, Sevda
    Azerbaijan Med Univ, Azerbaijan.
    Ahmed, Mohamed L. C. B.
    Univ Nouakchott Al Aasriya, Mauritania.
    Al Serouri, Abdulwahed
    Yemen Field Epidemiol Training Program, Yemen.
    Al-Shamsi, Humaid O.
    Univ Sharjah, U Arab Emirates; Burjeel Canc Inst, U Arab Emirates.
    Amir-Behghadami, Mehrdad
    Tabriz Univ Med Sci, Iran; Tabriz Univ Med Sci, Iran; Tabriz Univ Med Sci, Iran.
    Baatarkhuu, Oidov
    Mongolian Natl Univ Med Sci, Mongolia.
    Bashour, Hyam
    Damascus Univ, Syria.
    Bondarenko, Anastasiia
    Shupyk Natl Healthcare Univ Ukraine, Ukraine.
    Camacho-Ortiz, Adrian
    Univ Autonoma Nuevo Leon, Mexico.
    Castro, Franz
    Gorgas Mem Inst Hlth Studies, Panama.
    Cox, Horace
    Minist Hlth Guyana, Guyana.
    Davtyan, Hayk
    TB Res & Prevent Ctr NGO, Armenia.
    Douglas, Kirk
    Univ West Indies, Barbados.
    Dragioti, Elena
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för prevention, rehabilitering och nära vård. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Smärt och rehabiliteringscentrum.
    Ebrahim, Shahul
    Univ Sci Tech & Technol, Mali.
    Ferioli, Martina
    IRCCS Azienda Osped Univ Bologna, Italy.
    Harapan, Harapan
    Univ Syiah Kuala, Indonesia.
    Mallah, Saad I
    Royal Coll Surg Ireland Bahrain, Indonesia.
    Ikram, Aamer
    Natl Inst Hlth, Pakistan.
    Inoue, Shigeru
    Tokyo Med Univ, Japan.
    Jankovic, Slobodan
    Univ Kragujevac, Serbia.
    Jayarajah, Umesh
    Univ Colombo, Sri Lanka.
    Jesenak, Milos
    Comenius Univ, Slovakia.
    Kakodkar, Pramath
    Natl Univ Galway Ireland, Ireland.
    Kebede, Yohannes
    Jimma Univ, Ethiopia.
    Kifle, Meron
    Univ Oxford, England.
    Koh, David
    Natl Univ Singapore, Singapore.
    Males, Visnja K.
    Sch Med Split, Croatia.
    Kotfis, Katarzyna
    Pomeranian Med Univ, Poland.
    Lakoh, Sulaiman
    Univ Sierra Leone, Sierra Leone.
    Ling, Lowell
    Chinese Univ Hong Kong, Peoples R China.
    Llibre-Guerra, Jorge
    Washington Univ, MO USA.
    Machida, Masaki
    Tokyo Med Univ, Japan.
    Makurumidze, Richard
    Univ Zimbabwe, Zimbabwe.
    Mamun, Mohammed
    Chinese Univ Hong Kong, Peoples R China; Jahangirnagar Univ, Bangladesh; Daffodil Int Univ, Bangladesh; CHINTA Res Bangladesh, Bangladesh.
    Masic, Izet
    Acad Med Sci Bosnia & Herzegovina, Bosnia & Herceg.
    Van Minh, Hoang
    Hanoi Univ Publ Hlth, Vietnam.
    Moiseev, Sergey
    Sechenov First Moscow State Med Univ, Russia.
    Nadasdy, Thomas
    St Parascheva Clin Hosp Infect Dis, Romania.
    Nahshon, Chen
    Carmel Hosp, Israel.
    Namendys-Silva, Silvio A.
    Inst Nacl Ciencias Med & Nutr Salvador Zubiran, Mexico.
    Yongsi, Blaise N.
    Univ Yaounde II, Cameroon.
    Nielsen, Henning B.
    Zealand Univ Hosp Roskilde, Denmark.
    Nodjikouambaye, Zita A.
    Mobile Lab Hemorrhag & Resp Viruses Ndjamena, Chad.
    Ohnmar, Ohnmar
    Myanmar Hlth Minist, Myanmar.
    Oksanen, Atte
    Tampere Univ, Finland.
    Owopetu, Oluwatomi
    Univ Coll Hosp, Nigeria.
    Parperis, Konstantinos
    Univ Cyprus Med Sch, Cyprus.
    Perez, Gonzalo E.
    Clin Olivos, Argentina.
    Pongpirul, Krit
    Chulalongkorn Univ, Thailand.
    Rademaker, Marius
    Auckland Univ Med Sch, New Zealand.
    Rosa, Sandro
    Fed Fluminense Univ, Brazil; Natl Inst Ind Property, Brazil.
    Sah, Ranjit
    Natl Publ Hlth Lab, Nepal.
    Sallam, Dina
    Ain Shams Univ, Egypt.
    Schober, Patrick
    Vrije Univ Amsterdam, Netherlands.
    Singhal, Tanu
    Kokilaben Dhirubhai Ambani Hosp & Med Res Inst, India.
    Tafaj, Silva
    Univ Hosp Shefqet Ndroqi, Albania.
    Torres, Irene
    Fdn Octaedro, Ecuador.
    Smith Torres-Roman, J.
    Univ Cient Sur, Peru.
    Tsartsalis, Dimitrios
    Hippokrateion Hosp, Greece.
    Tsolmon, Jadamba
    Mongolian Natl Univ Med Sci, Mongolia.
    Tuychiev, Laziz
    Tashkent Med Acad, Uzbekistan.
    Vukcevic, Batric
    Univ Montenegro, Montenegro.
    Wanghi, Guy
    Univ Kinshasa, DEM REP CONGO.
    Wollina, Uwe
    Stadt Klinikum Dresden, Germany.
    Xu, Ren-He
    Univ Macau, Peoples R China.
    Yang, Lin
    Alberta Hlth Serv, Canada; Univ Calgary, Canada; Univ Calgary, Canada.
    Zaidi, Zoubida
    Univ Ferhat Abbas, Algeria.
    Smith, Lee
    Anglia Ruskin Univ, England.
    Shin, Jae Il
    Yonsei Univ, South Korea.
    The global case fatality rate of coronavirus disease 2019 by continents and national income: A meta-analysis2022Ingår i: Journal of Medical Virology, ISSN 0146-6615, E-ISSN 1096-9071, Vol. 94, nr 6, s. 2402-2413Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study is to provide a more accurate representation of COVID-19s case fatality rate (CFR) by performing meta-analyses by continents and income, and by comparing the result with pooled estimates. We used multiple worldwide data sources on COVID-19 for every country reporting COVID-19 cases. On the basis of data, we performed random and fixed meta-analyses for CFR of COVID-19 by continents and income according to each individual calendar date. CFR was estimated based on the different geographical regions and levels of income using three models: pooled estimates, fixed- and random-model. In Asia, all three types of CFR initially remained approximately between 2.0% and 3.0%. In the case of pooled estimates and the fixed model results, CFR increased to 4.0%, by then gradually decreasing, while in the case of random-model, CFR remained under 2.0%. Similarly, in Europe, initially, the two types of CFR peaked at 9.0% and 10.0%, respectively. The random-model results showed an increase near 5.0%. In high-income countries, pooled estimates and fixed-model showed gradually increasing trends with a final pooled estimates and random-model reached about 8.0% and 4.0%, respectively. In middle-income, the pooled estimates and fixed-model have gradually increased reaching up to 4.5%. in low-income countries, CFRs remained similar between 1.5% and 3.0%. Our study emphasizes that COVID-19 CFR is not a fixed or static value. Rather, it is a dynamic estimate that changes with time, population, socioeconomic factors, and the mitigatory efforts of individual countries.

  • 290. Beställ onlineKöp publikationen >>
    Aboulaich, Nabila
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Expanding role of caveolae in control of adipocyte metabolism: proteomics of caveolae2006Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The primary function of adipose tissue is to store energy in the form of triacylglycerol, which is hydrolyzed to fatty acids to supply other tissues with energy. While insulin promotes the storage of triacylglycerol, catecholamines stimulate its hydrolysis. The development of type II diabetes is strongly associated with obesity, indicating a role of triacylglycerol metabolism in the pathogenesis of diabetes. Caveolae are plasma membrane invaginations found in most cells but are highly abundant in adipocytes. Insulin receptors are localized in caveolae and their function depends on intact caveolae structures. In the present thesis work, mass spectrometry-based methodology allowed identification of a number of new proteins and their posttranslational modifications in caveolae of human adipocytes. Variable N-terminal acetylation and phosphorylation of caveolin-1α and caveolin-1β were identified, which might regulate the function of caveolae. The transcription regulator protein PTRF was identified as the major caveolae associated protein. Specific proteolytic modifications of PTRF at the cytosolic surface of caveolae and phosphorylation on nine serine and one threonine residues were identified. Moreover, insulin induced translocation of PTRF from the plasma membrane to the nucleus. PTRF was previously shown to regulate the activity of both RNA polymerase I and polymerase II, thus a role of PTRF in mediating the anabolic action of insulin on protein synthesis and gene transcription is proposed.

    PTRF was also involved in an extranuclear function in the hormonal regulation of triacylglycerol metabolism in caveolae. PTRF was colocalized with the triacylglycerol regulator proteins perilipin and hormone-sensitive lipase (HSL) in the triacylglycerol-synthesizing caveolae subclass. We showed that, while perilipin was translocated to the plasma membrane, both PTRF and HSL were translocated from the plasma membrane to the cytosol as a complex in response to insulin. The perilipin recruited to the plasma membrane was highly threonine phosphorylated. By mass spectrometry, three phosphorylated threonine residues were identified and were located in an acidic domain in the lipid droplet targeting domain of perilipin. The insulin-induced recruitment of perilipin to the plasma membrane might, therefore be phosphorylation-dependent. Isoproterenol, which stimulates hydrolysis of triacylglycerol, induced a complete depletion of perilipin B from the plasma membrane, suggesting a function of perilipin B to protect newly synthesized triacylglycerol in caveolae from being hydrolyzed by HSL. The location of PTRF and HSL was not affected by isoproterenol, indicating that insulin is acting against a default presence of PTRF and HSL in caveolae.

    Taken together, this thesis expands our knowledge about caveolae and provided valuable information about their involvement in novel roles, particularly in the hormonal regulation of triacylglycerol metabolism.

    Delarbeten
    1. Vectorial proteomics reveal targeting, phosphorylation and specific fragmentation of polymerase I and transcript release factor (PTRF) at the surface of caveolae in human adipocytes
    Öppna denna publikation i ny flik eller fönster >>Vectorial proteomics reveal targeting, phosphorylation and specific fragmentation of polymerase I and transcript release factor (PTRF) at the surface of caveolae in human adipocytes
    2004 (Engelska)Ingår i: The Biochemical journal, ISSN 1470-8728, Vol. 383, nr Pt 2, s. 237-248Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Caveolae, the specialized invaginations of plasma membranes, formed sealed vesicles with outwards-orientated cytosolic surface after isolation from primary human adipocytes. This morphology allowed differential, vectorial identification of proteins at the opposite membrane surfaces by proteolysis and MS. Extracellular-exposed caveolae-specific proteins CD36 and copper-containing amine oxidase were concealed inside the vesicles and resisted trypsin treatment. The cytosol-orientated caveolins were efficiently digested by trypsin, producing peptides amenable to direct MS sequencing. Isolation of peripheral proteins associated with the cytosolic surface of caveolae revealed a set of proteins that contained nuclear localization signals, leucine-zipper domains and PEST (amino acid sequence enriched in proline, glutamic acid, serine and threonine) domains implicated in regulation by proteolysis. In particular, PTRF (polymerase I and transcript release factor) was found as a major caveolae-associated protein and its co-localization with caveolin was confirmed by immunofluorescence confocal microscopy. PTRF was present at the surface of caveolae in the intact form and in five different truncated forms. Peptides (44 and 45 amino acids long) comprising both the PEST domains were sequenced by nanospray-quadrupole-time-of-flight MS from the full-length PTRF, but were not found in the truncated forms of the protein. Two endogenous cleavage sites corresponding to calpain specificity were identified in PTRF; one of them was in a PEST domain. Both cleavage sites were flanked by mono- or diphosphorylated sequences. The phosphorylation sites were localized to Ser-36, Ser-40, Ser-365 and Ser-366 in PTRF. Caveolae of human adipocytes are proposed to function in targeting, relocation and proteolytic control of PTRF and other PEST-domain-containing signalling proteins.

    Nyckelord
    Caveolae, human adipocyte, MS, PEST sequence, polymerase I and transcript release factor (PTRF), proteolysis
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-19145 (URN)10.1042/BJ20040647 (DOI)15242332 (PubMedID)
    Tillgänglig från: 2009-06-12 Skapad: 2009-06-12 Senast uppdaterad: 2009-06-12Bibliografiskt granskad
    2. N-terminal processing and modifications of caveolin-1 in caveolae from human adipocytes
    Öppna denna publikation i ny flik eller fönster >>N-terminal processing and modifications of caveolin-1 in caveolae from human adipocytes
    Visa övriga...
    2004 (Engelska)Ingår i: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 320, nr 2, s. 480-486Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Caveolin, the principal structural protein of caveolae membrane domains, has a cytosol-exposed N-terminal part that was cleaved off by trypsin treatment of caveolae vesicles isolated from primary human adipocytes. Sequencing of the released tryptic peptides by nanospray quadrupole time-of-flight mass spectrometry revealed that both caveolin-1alpha and caveolin-1beta were processed by excision of the starting methionines. The N-terminus of the mature caveolin-1alpha was acetylated, while caveolin-1beta was found in acetylated as well as in non-acetylated forms. Fractional phosphorylation of serine-36 in the mature caveolin-1alpha and of the homologous serine-5 in caveolin-1beta was identified. This is the first experimental evidence for in vivo phosphorylation of caveolin-1 at the consensus site for phosphorylation by protein kinase C. The phosphorylation was found in both the acetylated and non-acetylated variants of caveolin-1beta. This variability in modifications is consistent with critical involvement of the N-terminal domain of caveolin in the regulation of caveolae.

    Nyckelord
    Human adipocyte, Caveolin-1; Caveolae, Protein phosphorylation, N-terminal acetylation, Mass spectrometry
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-19146 (URN)10.1016/j.bbrc.2004.05.196 (DOI)15219854 (PubMedID)
    Tillgänglig från: 2009-06-12 Skapad: 2009-06-12 Senast uppdaterad: 2017-12-13Bibliografiskt granskad
    3. Hormonal control of reversible translocation of perilipin B to the plasma membrane in primary human adipocytes
    Öppna denna publikation i ny flik eller fönster >>Hormonal control of reversible translocation of perilipin B to the plasma membrane in primary human adipocytes
    2006 (Engelska)Ingår i: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 281, nr 17, s. 11446-11449Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In adipocytes, perilipin coats and protects the central lipid droplet, which stores triacylglycerol. Alternative mRNA splicing gives rise to perilipin A and B. Hormones such as catecholamines and insulin regulate triacylglycerol metabolism through reversible serine phosphorylation of perilipin A. It was recently shown that perilipin was also located in triacylglycerol-synthesizing caveolae of the plasma membrane. We now report that perilipin at the plasma membrane of primary human adipocytes was phosphorylated on a cluster of threonine residues (299, 301, and 306) within an acidic domain that forms part of the lipid targeting domain. Perilipin B comprised <10% of total perilipin but was the major isoform associated with the plasma membrane of human adipocytes. This association was controlled by insulin and catecholamine: perilipin B was specifically depleted from the plasma membrane in response to the catecholamine isoproterenol, while insulin increased the amount of threonine phosphorylated perilipin at the plasma membrane. The reversible translocation of perilipin B to and from the plasma membrane in response to insulin and isoproterenol, respectively, suggests a specific function for perilipin B to protect newly synthesized triacylglycerol in the plasma membrane.

    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-19147 (URN)10.1074/jbc.C500461200 (DOI)16527823 (PubMedID)
    Tillgänglig från: 2009-06-12 Skapad: 2009-06-12 Senast uppdaterad: 2017-12-13Bibliografiskt granskad
    4. Association and insulin regulated translocation of hormone-sensitive lipase with PTRF
    Öppna denna publikation i ny flik eller fönster >>Association and insulin regulated translocation of hormone-sensitive lipase with PTRF
    2006 (Engelska)Ingår i: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 350, nr 3, s. 657-661Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Polymerase I and transcript release factor (PTRF) is in human adipocytes mainly localized at the plasma membrane. This localization was under control of insulin, which translocated PTRF to the cytosol and nucleus, indicating a novel role for PTRF in insulin transcriptional control. In the plasma membrane PTRF was specifically bound to a triacylglycerol-metabolizing subclass of caveolae containing hormone-sensitive lipase (HSL). In response to insulin PTRF was translocated to the cytosol in parallel with HSL. PTRF and HSL were quantitatively immunoprecipitated from the cytosol by antibodies against either PTRF or HSL. The findings indicate also a novel extranuclear function for PTRF in the control of lipolysis.

    Nyckelord
    Hormone-sensitive lipase, Polymerase I and transcript release factor, Adipocyte, Human, Insulin, Translocation, Protein complex, Caveolae, Lipid metabolism, Transcriptional control
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-19148 (URN)10.1016/j.bbrc.2006.09.094 (DOI)17026959 (PubMedID)
    Tillgänglig från: 2009-06-12 Skapad: 2009-06-12 Senast uppdaterad: 2017-12-13Bibliografiskt granskad
    Ladda ner fulltext (pdf)
    Expanding Role of Caveolae in Control of Adipocyte Metabolism
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    Cover
  • 291.
    Aboulaich, Nabila
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Ortegren, Unn
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Vener, Alexander V
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Strålfors, Peter
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Association and insulin regulated translocation of hormone-sensitive lipase with PTRF2006Ingår i: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 350, nr 3, s. 657-661Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Polymerase I and transcript release factor (PTRF) is in human adipocytes mainly localized at the plasma membrane. This localization was under control of insulin, which translocated PTRF to the cytosol and nucleus, indicating a novel role for PTRF in insulin transcriptional control. In the plasma membrane PTRF was specifically bound to a triacylglycerol-metabolizing subclass of caveolae containing hormone-sensitive lipase (HSL). In response to insulin PTRF was translocated to the cytosol in parallel with HSL. PTRF and HSL were quantitatively immunoprecipitated from the cytosol by antibodies against either PTRF or HSL. The findings indicate also a novel extranuclear function for PTRF in the control of lipolysis.

  • 292.
    Aboulaich, Nabila
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Vainonen, Julia P
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Strålfors, Peter
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Vener, Alexander V
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Vectorial proteomics reveal targeting, phosphorylation and specific fragmentation of polymerase I and transcript release factor (PTRF) at the surface of caveolae in human adipocytes2004Ingår i: The Biochemical journal, ISSN 1470-8728, Vol. 383, nr Pt 2, s. 237-248Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Caveolae, the specialized invaginations of plasma membranes, formed sealed vesicles with outwards-orientated cytosolic surface after isolation from primary human adipocytes. This morphology allowed differential, vectorial identification of proteins at the opposite membrane surfaces by proteolysis and MS. Extracellular-exposed caveolae-specific proteins CD36 and copper-containing amine oxidase were concealed inside the vesicles and resisted trypsin treatment. The cytosol-orientated caveolins were efficiently digested by trypsin, producing peptides amenable to direct MS sequencing. Isolation of peripheral proteins associated with the cytosolic surface of caveolae revealed a set of proteins that contained nuclear localization signals, leucine-zipper domains and PEST (amino acid sequence enriched in proline, glutamic acid, serine and threonine) domains implicated in regulation by proteolysis. In particular, PTRF (polymerase I and transcript release factor) was found as a major caveolae-associated protein and its co-localization with caveolin was confirmed by immunofluorescence confocal microscopy. PTRF was present at the surface of caveolae in the intact form and in five different truncated forms. Peptides (44 and 45 amino acids long) comprising both the PEST domains were sequenced by nanospray-quadrupole-time-of-flight MS from the full-length PTRF, but were not found in the truncated forms of the protein. Two endogenous cleavage sites corresponding to calpain specificity were identified in PTRF; one of them was in a PEST domain. Both cleavage sites were flanked by mono- or diphosphorylated sequences. The phosphorylation sites were localized to Ser-36, Ser-40, Ser-365 and Ser-366 in PTRF. Caveolae of human adipocytes are proposed to function in targeting, relocation and proteolytic control of PTRF and other PEST-domain-containing signalling proteins.

  • 293.
    Aboulaich, Nabila
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Vener, Alexander V
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Strålfors, Peter
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Hormonal control of reversible translocation of perilipin B to the plasma membrane in primary human adipocytes2006Ingår i: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 281, nr 17, s. 11446-11449Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In adipocytes, perilipin coats and protects the central lipid droplet, which stores triacylglycerol. Alternative mRNA splicing gives rise to perilipin A and B. Hormones such as catecholamines and insulin regulate triacylglycerol metabolism through reversible serine phosphorylation of perilipin A. It was recently shown that perilipin was also located in triacylglycerol-synthesizing caveolae of the plasma membrane. We now report that perilipin at the plasma membrane of primary human adipocytes was phosphorylated on a cluster of threonine residues (299, 301, and 306) within an acidic domain that forms part of the lipid targeting domain. Perilipin B comprised <10% of total perilipin but was the major isoform associated with the plasma membrane of human adipocytes. This association was controlled by insulin and catecholamine: perilipin B was specifically depleted from the plasma membrane in response to the catecholamine isoproterenol, while insulin increased the amount of threonine phosphorylated perilipin at the plasma membrane. The reversible translocation of perilipin B to and from the plasma membrane in response to insulin and isoproterenol, respectively, suggests a specific function for perilipin B to protect newly synthesized triacylglycerol in the plasma membrane.

  • 294.
    Aboulazze, Nawal
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling. Linköpings universitet, Filosofiska fakulteten.
    Nordström, Frida
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling. Linköpings universitet, Filosofiska fakulteten.
    Exklusiva varumärkens strategier kring digitala kundrelationer: Hur svenska exklusiva varumärken skapar kundrelationer via sociala medier2022Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Bakgrund: Idag väljer allt fler företag inom mode- och inredningsindustrin att sälja sina produkter online. Företagens interaktioner och marknadsföring sker därför mestadels digitalt gentemot kunden. Denna nya era av digitalisering för företagen innebär en stor förändring vad gäller nya former av marknadsföring och kundkontakt. Tidigare har exklusiva företag främst använt sig av butiksmedarbetare i fysiska butiker för att överföra känslan av lyx och exklusivitet till kunden, vilket utmanar denna bransch i en digital kontext. Vidare förväntas exklusiva företag idag ha en transparens gällande hållbarhet och miljömässigt avtryck i sin kommunikation mot kunden. Samtidigt innebär detta en högre risk för kritisering. Studien kommer därför att vidare undersöka de utmaningar som nio exklusiva företag upplever kring skapande och underhåll av kundrelationer i en digital kontext.

    Syfte: Syftet med denna studie är att beskriva och analysera hur svenska exklusiva varumärken skapar samt bibehåller relationer till sina kunder via sociala medier. Studien kommer senare bidra med slutsatser kring hur de exklusiva svenska varumärkena bör agera för att förbättra sina relationer till sina kunder via sociala medier.

    Metod: Denna fallstudie har en kvalitativ forskningsstrategi. Ett hermeneutiskt vetenskapligt perspektiv har valts tillsammans med induktiva inslag. Den kvalitativa datainsamlingen består av semistrukturerade intervjuer med tio respondenter från nio svenska, exklusiva företag inom mode- och inredningsbranschen.

    Slutsats: Studiens resultat visar att de svenska exklusiva företagen skapar samt bibehåller relationer med sina kunder genom parasociala interaktioner på sociala medier. Detta utförs genom digitala strategier som storytelling, sinnesmarknadsföring, word of mouth, CRM samt värdeskapande. Aspekter som utmanar de exklusiva företagens digitala relationsskapande är företagens storlek, sinnesexkludering, tidsbrist och kapital. Vidare visar studien att företagen bör öka sin transparens gällande hållbarhet gentemot sina kunder för att uppnå ett ökat förtroende.

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  • 295. Beställ onlineKöp publikationen >>
    Abouzeedan, Adli
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling. Linköpings universitet, Tekniska högskolan.
    SME Performance and Its Relationship to Innovation2011Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Current SME performance models suffer from a number of disadvantages. The models use intensively a business ratio approach, they look at SMEs as a homogenous group, they consider firms to be closed systems, they do not directly incorporate the impact of an enterprise’s innovation activities, and finally they are complex and rely on sophisticated statistical refining methods making them unpractical to use by SME managers. There are four major challenges when one tries to build SME performance models that lack these deficiencies. The first challenge is that the desired performance evaluation model must optimally incorporate both quantitative and qualitative input. The second challenge is that the model must incorporate non-financial input parameters, such as firm size and age (among others), in the performance evaluation models. The third is that the model must consider the variety of SMEs as concerns their business sectors, nationalities, sizes, and ages. The final challenge is that the model must be able to utilize existing limited information available from the SMEs bookkeeping practices in an optimal way.

    The thesis addresses three questions related to constructing a better SMEperformance model, namely (1) What are the advantages and disadvantages of the existing models used in evaluating SME performance? (2) What characterizes a comprehensive model for measuring SME performance with acknowledgement of the firm’s innovation activities? (3) How can a firm’s innovation activities be enhanced in relation to the firm’s external environment?

    To construct a model that copes with these challenges, I used a literature-based selection of parameters as well as a theory-based selection. I used both a conceptual approach and an empirical approach to discuss and propose a model, the Survival Index Value (or SIV) model, as an alternative to the existing performance models for SMEs.

    The major contributions of this thesis to the field of SME performance can be summarized in three outcomes: the SIV model as a new model of SME performance evaluation, the ASPEM as a new tool for strategic utilization of SME performance models, and a new approach to account for innovation in relation to the external environment of the firm using the IBAM tool.

    The work adds to the theory of the firm, as it presents a new way of evaluating firm performance. It also contributes to bridging the theory of the firm to organizational theory, by elevating the significance of networking and its impact on SME efficiency.

    Delarbeten
    1. Typology Analysis of Performance Models of Small and Medium-Size Enterprises (SMEs)
    Öppna denna publikation i ny flik eller fönster >>Typology Analysis of Performance Models of Small and Medium-Size Enterprises (SMEs)
    2004 (Engelska)Ingår i: International Journal of Entrepreneurship, ISSN 1099-9264, E-ISSN 1939-4675, Vol. 2, nr 1-2, s. 155-177Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A number of firm performance models are available. Reviewing these models and pointing out their individual strengths and weaknesses, would help both academic researchers and professional users to understand and appreciate how and when to use these various models. The theoretical models for Small and Medium-size Enterprise (SME) performance can be divided into two categories: firm dynamics theories and performance prediction models. In the first part of this paper we review, in a condensed manner, the most relevant firm dynamic theories, i.e. SME's performance models. These include: Stochastic Theories, Learning Model Theories and Hazard Modeling Theories. In the second part of this paper, we examine the performance prediction models of SMEs, which include Z-Scores, ZETA-Scores, Neural Networks (NN) and the SIV® models, among others. The strengths and weaknesses of each of these models are exposed and discussed.

    Ort, förlag, år, upplaga, sidor
    SpringerLink, 2004
    Nyckelord
    small and medium-size enterprises - survival index value - SIV® model - Z-scores - neural networks
    Nationell ämneskategori
    Ekonomi och näringsliv
    Identifikatorer
    urn:nbn:se:liu:diva-71336 (URN)10.1023/B:JIEN.0000026911.03396.2d (DOI)
    Tillgänglig från: 2011-10-12 Skapad: 2011-10-12 Senast uppdaterad: 2017-12-08Bibliografiskt granskad
    2. ASPEM as the New Topographic Analysis Tool for Small and Medium-Sized Enterprises (SMEs) Performance Models Utilization
    Öppna denna publikation i ny flik eller fönster >>ASPEM as the New Topographic Analysis Tool for Small and Medium-Sized Enterprises (SMEs) Performance Models Utilization
    2005 (Engelska)Ingår i: International Journal of Entrepreneurship, ISSN 1099-9264, E-ISSN 1939-4675, Vol. 3, nr 1, s. 53-70Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Quantifying and measuring small firm performance is vital in our understanding of how internationalization influences firm performance. That is also important when attempting to grasp the mechanisms of the internationalization processes. There are few methods used for the evaluation of performance of Small and Medium-sized Enterprise (SMEs). These methods can be either macro or micro economic in nature. Hazard Modeling, Stochastic Models, and Learning Models are examples of macro economic models while Z-Scores, ZETA-Scores, Neural Networks, and the SIV® model are examples of micro models. Choosing the most suitable performance model is an essential step in order to maximize our knowledge in relation to firm performance. Utilizing SMEs performance measures without thinking about the category of model, will bias the outcome of the majority of SMEs studies. However, using firm performance diverse models in an efficient manner requires strategic thinking. In this paper, we are re-introducing a tool that can accommodate that aspect. Abouzeedan (2002) designated the new tool: the Arena of SMEs Performance Models or an ASPEM diagram. The horizontal axis in the diagram indicates the Information Intensity Requirements of the model. The vertical axis indicates the Coverage Intensity of the model varying from an individual firm up to a whole group of firms. By allocating each of the SMEs performance models, at the suitable region of the ASPEM Diagram, researchers can better build a sound strategy for the application of these methods.

    Ort, förlag, år, upplaga, sidor
    SpringerLink, 2005
    Nyckelord
    Arena of SMEs performance models, ASPEM - SIV® model, Zeta-scores, ZETA-scores, neural networks, stochastic theories, hazard modeling
    Nationell ämneskategori
    Ekonomi och näringsliv
    Identifikatorer
    urn:nbn:se:liu:diva-71337 (URN)10.1007/s10843-005-0305-4 (DOI)
    Tillgänglig från: 2011-10-12 Skapad: 2011-10-12 Senast uppdaterad: 2017-12-08Bibliografiskt granskad
    3. Analysis of Swedish Fishery Company Using SIV® Model: A Case Study
    Öppna denna publikation i ny flik eller fönster >>Analysis of Swedish Fishery Company Using SIV® Model: A Case Study
    2004 (Engelska)Ingår i: Journal of Enterprising Culture, ISSN 0218-4958, Vol. 12, nr 4, s. 277-301Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In his original work of the Survival Index Value (SIV®) model, Dr. Adli Abouzeedan proposed a new parameter, which he named as the Survival Index (SI) (see Abouzeedan, 2001; Abouzeedan and Busler, 2002a). The new parameter is used to evaluate the performance of Small and Medium-size Enterprises (SMEs) utilizing firm survivability as an indicator. The SI is calculated using an equation known as Survival Index (SI) Value Equation or SIE. In this paper, we applied the SIV® model to run an analysis on a very young Swedish firm and up to our knowledge, for the first time. The firm is a small one, working within a business sector defined as "fish preparation industry". This particular enterprise had a bad performance through its short life. The purpose of this study is to truly determine if the SIV® model has the capacity to indicate the performance of the firm. The case study presented in this work showed the valuable analytical power of the new model since it succeeded in giving a clear indication of the worsening situation of the enterprise. During the SIV® analysis of this Swedish firm new concepts have been introduced which do increase the practicality and analytical capacity of the model.

    Ort, förlag, år, upplaga, sidor
    World Scientific Publishing Co., 2004
    Nationell ämneskategori
    Ekonomi och näringsliv
    Identifikatorer
    urn:nbn:se:liu:diva-71340 (URN)10.1142/S0218495804000154 (DOI)
    Tillgänglig från: 2011-10-12 Skapad: 2011-10-12 Senast uppdaterad: 2017-12-08Bibliografiskt granskad
    4. Innovation Balance Matrix: an application in the Arab countries
    Öppna denna publikation i ny flik eller fönster >>Innovation Balance Matrix: an application in the Arab countries
    2006 (Engelska)Ingår i: World Review of Entrepreneurship, Management and Sustainable Development, ISSN 1746-0573, E-ISSN 1746-0581, Vol. 2, nr 3, s. 270-280Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Economies have different levels of entrepreneurial activities depending on the availability of tangible as well as intangible resources. In their working paper, Abouzeedan and Busler (2004) established a new type of capital, adding up the components of the most important types of capital. These are the human capital, financial capital and the system capital. In that paper, the two researchers defined each of the components and explained what they meant with those terminologies. They called this new type of capital, innovation capital. The two researchers have argued that innovation capital can be used as an indicator for the degree of richness of the entrepreneurial environment in a region and thus the general character of the economy. They also introduced the Innovation Balance Matrix or IBAM as an analytical tool to classify economies based on their entrepreneurial conditions. In this extended work, they have used this analysis and tried to apply it to Arab countries using a general knowledge and deductive approach to the issue. They conclude the paper with some recommendations as how to enrich the innovation capital in that region.

    Ort, förlag, år, upplaga, sidor
    Inderscience Enterprises Limited, 2006
    Nyckelord
    Human capital; financial capital; system capital; innovation capital; innovation balance matrix; IBAM; Arab countries; Middle East; entrepreneurship.
    Nationell ämneskategori
    Ekonomi och näringsliv
    Identifikatorer
    urn:nbn:se:liu:diva-71341 (URN)10.1504/WREMSD.2006.009893 (DOI)
    Tillgänglig från: 2011-10-12 Skapad: 2011-10-12 Senast uppdaterad: 2017-12-08Bibliografiskt granskad
    5. Entrepreneurial policies and the innovation balance matrix: the case of the Arab countries
    Öppna denna publikation i ny flik eller fönster >>Entrepreneurial policies and the innovation balance matrix: the case of the Arab countries
    2007 (Engelska)Ingår i: Science,Technology and Sustainability in the Middle East and North Africa: Section III: Science Technology and Innovation / [ed] Allam Ahmed, Inderscience Enterprises Limited , 2007, s. 158-175Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The issue of the connection between economic progress and the entrepreneurial environment has been investigated by researchers using diverse approaches. One way to investigate the question is to use deductive analysis regarding the forms of capital contributing to the entrepreneurial environment of society. Adli Abouzeedan and Michael Busler were the first to introduce the concept of 'Innovation Capital'. The two researchers argued that Innovation Capital can be used as an indicator for the degree of richness of the entrepreneurial environment. In the same paper, the researchers also introduced the Innovation Balance Matrix (IBAM) as an analytical tool to classify economies based on their entrepreneurial conditions, applying it across the globe. In a later work, the two researchers tried to run a similar IBAM analysis focusing on the Arab world. The two writers found that the best solution to the lack of individual entrepreneurial economies in that region is through what they called the 'additive solution'. In this work, we take their argument deeper and look at the kind of policies that would achieve that solution.

    Ort, förlag, år, upplaga, sidor
    Inderscience Enterprises Limited, 2007
    Serie
    Globalisation, Technology and Sustainable Development Book Series
    Nationell ämneskategori
    Ekonomi och näringsliv
    Identifikatorer
    urn:nbn:se:liu:diva-71342 (URN)0-907776-30-2 (ISBN)0-907776-32-9 (ISBN)
    Tillgänglig från: 2011-10-12 Skapad: 2011-10-12 Senast uppdaterad: 2011-11-21Bibliografiskt granskad
    6. Managing Innovation in a Globalised Economy: Defining the Open Capital
    Öppna denna publikation i ny flik eller fönster >>Managing Innovation in a Globalised Economy: Defining the Open Capital
    2009 (Engelska)Ingår i: World Sustainable Development Outlook 2009. The Impact of the Global Financial Crisis on the Environment, Energy and Sustainable Development / [ed] Allam Ahmed, World Association for Sustainable Development , 2009, s. 287-294Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Economies develop different levels of entrepreneurial capacity depending on the degree of availability of tangible as well as intangible resources. In an earlier work by Abouzeedan and Busler (2006), a new type of capital, that is, innovation capital, has been suggested to serve as an indicator for the degree of richness of the entrepreneurial environment in an economy. Innovation capital incorporates the concepts of human capital, financial capital and system capital. However, the issue of accessibility and openness in the innovation process also need to be reflected in the innovation capital concept. Innovation activities in the modern economies are growing to become more interconnected and open in their nature. In this paper, we defined and incorporated a new component within the innovation capital, namely open capital. We also reflected on how the four components of the innovation capital concept, including the open capital, are interconnected.

    Ort, förlag, år, upplaga, sidor
    World Association for Sustainable Development, 2009
    Nyckelord
    Open Capital, Human Capital, Financial Capital, System Capital, Innovation Capital, Open Innovation, Open Innovation Management
    Nationell ämneskategori
    Ekonomi och näringsliv
    Identifikatorer
    urn:nbn:se:liu:diva-71344 (URN)978-1-907106-05-7 (ISBN)
    Tillgänglig från: 2011-10-12 Skapad: 2011-10-12 Senast uppdaterad: 2011-11-21Bibliografiskt granskad
    7. Analysis of a Swedish High Technology SME Using the Survival Index Value (SIV) Model
    Öppna denna publikation i ny flik eller fönster >>Analysis of a Swedish High Technology SME Using the Survival Index Value (SIV) Model
    2011 (Engelska)Ingår i: Paper Sessions, Workshops and Special Meetings: The 56th ICSB World Conference, Stockholm, Sweden, 15th and 18th of June, ICSB , 2011, s. 170-179Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    One of the major deficiencies in the existing Small and Medium-sized Enterprises’ (SMEs) performance evaluation models is the fact that they lack a clear coupling to the issue of innovation and its impact on performance. A possible candidate model which could achieve this is the Survival Index Value (SIV) model. The model has a parameter incorporated in its structure, the technology-intake. This parameter can be used as an indicator of the degree of innovativeness of the firm. Previous works using the model looked at general performance without specific focus on innovation activities of the firm and without relating that to aspects of survival and growth. In this paper the aim was to demonstrate the ability of the SIV model to indicate a positive overall performance due to the intensive investment of a selected firm in innovation activities.

    The enterprise analyzed, Autoadapt AB, is a Swedish high technology firm working in adapting cars and automobiles to handicapped people. Due to the nature of their activities the firm has a high level of innovation input to be able to solve the complex problems related to usage of cars by disabled people. Both the product development process and managing the activities around it requires a high level of innovativeness and ingenuity. As thus the firm presented a very interesting object to study. The study has a clear significance as there is a need to differentiate the performance of innovation-intensive enterprises from firms who are using less investment in innovation in their activities. This can be done by considering the investment in new technologies both as product development and/or as investing in absorption of external management, product or process innovation. Applying the SIV model to run this analysis can help to demonstrate the need to incorporate the technology intake as an essential component of SME’s performance model.

    The results indicated that the SIVmodel is able to predict correctly the performance of the object firm. By having mostly positive survival factor values, which are single data-points, during years of operation, and also having mostly positive survivability coefficient values, which are agglomerate data-points, the SIVmodel proved its abilities. Clearly, the model has a good potential to be developed and fine-tuned even more. The SIV model can be tested further to look at deviations in performance of firms among different sectors and relates that to the innovativeness of whole sectors.

    Ort, förlag, år, upplaga, sidor
    ICSB, 2011
    Nyckelord
    small and medium-sized enterprises, SMEs, performance evaluation models, SIV model
    Nationell ämneskategori
    Ekonomi och näringsliv
    Identifikatorer
    urn:nbn:se:liu:diva-71345 (URN)978-0-9819028-3-8 (ISBN)0-9819028-3-9 (ISBN)
    Konferens
    ICSB 2011 World Conference Date: June 15-18, 2011, Stockholm Waterfront Congress Center, Stockholm, Sweden
    Tillgänglig från: 2011-10-12 Skapad: 2011-10-12 Senast uppdaterad: 2016-05-04Bibliografiskt granskad
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    SME Performance and Its Relationship to Innovation
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    omslag
  • 296.
    Abouzeedan, Adli
    et al.
    Innovation and Entrepreneurship, Department of Medicine Sahlgrenska Academy, University of Göteborg, Göteborg, Sweden.
    Hedner, Thomas
    Innovation and Entrepreneurship, Department of Medicine Sahlgrenska Academy, University of.
    Klofsten, Magnus
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Projekt, innovationer och entreprenörskap. Linköpings universitet, Tekniska fakulteten. Linköpings universitet, HELIX Competence Centre.
    Innovation and entrepreneurship – new themes for new times2010Ingår i: Annals of Innovation & Entrepreneurship, ISSN 2000-7396, Vol. 1, nr 1, s. 1-3Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Throughout history, innovators and entrepreneurs have had a tremendous impact on development, exploration, trade, education, science, and integration. During the 20th century, innovation and entrepre-neurship have been regarded as key drivers in technological progress and productivity development worldwide. New radical innovations from new fields of knowledge such as information and communication technologies and biotechnology have emerged to influence everyday life for most people. Realizing this, policy makers as well as individuals argue that innovative and entrepreneurial change processes need to be further implemented on the micro as well as macro levels in society (Abouzeedan, Busler, & Hedner, 2009; Busenitz, Gomez, & Spencer, 2000). The study of innovation is therefore likely to be an increasingly important topic in, for example, economics, business, entrepreneurship, tech-nology, engineering, medicine, environmental biology, sociology, design, and reregional development (cf. Etzkowitz & Klofsten, 2005).

    Ladda ner fulltext (pdf)
    fulltext
  • 297.
    Abouzeedan, Adli
    et al.
    Sahlgrenska Academy, University of Gothenburg, Sweden.
    Klofsten, Magnus
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Projekt, innovationer och entreprenörskap. Linköpings universitet, Tekniska högskolan.
    Hedner, Thomas
    Sahlgrenska Academy, University of Gothenburg, Sweden.
    Analysis of a Swedish High Technology SME Using the Survival Index Value (SIV) Model2011Ingår i: Paper Sessions, Workshops and Special Meetings: The 56th ICSB World Conference, Stockholm, Sweden, 15th and 18th of June, ICSB , 2011, s. 170-179Konferensbidrag (Refereegranskat)
    Abstract [en]

    One of the major deficiencies in the existing Small and Medium-sized Enterprises’ (SMEs) performance evaluation models is the fact that they lack a clear coupling to the issue of innovation and its impact on performance. A possible candidate model which could achieve this is the Survival Index Value (SIV) model. The model has a parameter incorporated in its structure, the technology-intake. This parameter can be used as an indicator of the degree of innovativeness of the firm. Previous works using the model looked at general performance without specific focus on innovation activities of the firm and without relating that to aspects of survival and growth. In this paper the aim was to demonstrate the ability of the SIV model to indicate a positive overall performance due to the intensive investment of a selected firm in innovation activities.

    The enterprise analyzed, Autoadapt AB, is a Swedish high technology firm working in adapting cars and automobiles to handicapped people. Due to the nature of their activities the firm has a high level of innovation input to be able to solve the complex problems related to usage of cars by disabled people. Both the product development process and managing the activities around it requires a high level of innovativeness and ingenuity. As thus the firm presented a very interesting object to study. The study has a clear significance as there is a need to differentiate the performance of innovation-intensive enterprises from firms who are using less investment in innovation in their activities. This can be done by considering the investment in new technologies both as product development and/or as investing in absorption of external management, product or process innovation. Applying the SIV model to run this analysis can help to demonstrate the need to incorporate the technology intake as an essential component of SME’s performance model.

    The results indicated that the SIVmodel is able to predict correctly the performance of the object firm. By having mostly positive survival factor values, which are single data-points, during years of operation, and also having mostly positive survivability coefficient values, which are agglomerate data-points, the SIVmodel proved its abilities. Clearly, the model has a good potential to be developed and fine-tuned even more. The SIV model can be tested further to look at deviations in performance of firms among different sectors and relates that to the innovativeness of whole sectors.

  • 298.
    Abouzeedan, Adli
    et al.
    University of Gothenburg.
    Klofsten, Magnus
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Projekt, innovationer och entreprenörskap. Linköpings universitet, Tekniska högskolan.
    Hedner, Thomas
    University of Gothenburg.
    Implementing the SIV Model on an Intensively Innovation-Oriented Firm: The Case of Autoadapt AB2012Ingår i: World Journal of Entrepreneurship, Management and Sustainable Development, ISSN 2042-5961, Vol. 8, nr 2/3, s. 122-145Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Small to medium-sized enterprise (SME) evaluation models lack a clear coupling to innovation and its impact on firm performance. A model which can achieve this is the Survival Index Value (SIV) model. The purpose of this paper is to demonstrate the ability of the SIV model to indicate and predict the performance of a company. The firm, Autoadapt AB, is an innovation-oriented enterprise, adapting personal cars to be driven by handicapped people. The authors knew in advance about the good performance of the firm and its high efficiency in conducting its operations and expected the SIV model to reflect correctly on Autoadapt's performance. Because the handicap degree of each of the individuals who benefit from the firm activities differs from one person to another, product solutions have to be individually designed. Therefore the firm has had to pursue a high level of innovativeness and it had to abide with this policy right from the start. The product development processes in the firm needed to adapt to such strategies.

    To be able to demonstrate the ability of the SIV model to indicate a positive performance due to the intensive innovation activities of Autoadapt AB, a case study approach was used. Case studies are very suited for in-depth analysis of an object under a longer period of time. It is a widely-used research method in firm performance studies.

    The results of the SIV analysis indicated that the model is able to project correctly the performance of the object firm. At all the four levels of analysis, i.e. SI values, the SPI slope, the survival factors, and the survivability coefficients, the SIV analysis performance indicated a stable positive development of the firm through the life time of the enterprise.

    Measuring performance of SMEs is an important issue. There are couple of models stemming from the traditional accountancy disciplines in use; however these models suffer from clear disadvantages. Recently a new model, the SIV model, was introduced and has shown the ability of being a better candidate for performance analysis. The paper demonstrates the ability of the SIV model to judge correctly the performance of an innovative firm.

  • 299.
    Aboyans, Victor
    et al.
    Dupuytren University Hospital.
    Criqui, Michael
    University of California, USA.
    Abraham, Pierre
    University Hospital of Angers, France.
    Allison, Matthew
    University of California, USA.
    Creager, Mark
    Brigham and Women’s Hospital, USA.
    Diehm, Curt
    Karlsbad Clinic/University of Heidelberg, Germany.
    Fowkes, Gerry
    University of Edinburgh, UK.
    Hiatt, William
    University of Colorado, USA.
    Jönsson, Björn
    Linköpings universitet, Institutionen för medicin och hälsa, Thoraxkirurgi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Hjärt- och Medicincentrum, Thorax-kärlkliniken i Östergötland.
    Lacroix, Philippe
    Limoges University, France.
    Marin, Benoit
    Limoges Teaching Hospital, France.
    McDermott, Mary
    Northwestern University,USA.
    Norgren, Lars
    University Hospital, Örebro, Sweden.
    Pande, Reena
    Brigham and Women’s Hospital, USA.
    Preux, Pierre-Marie
    University of Limoges, France.
    Stoffers, H.E.
    Maastricht University, Netherlands.
    Treat-Jacobsson, Diane
    University of Minnesota, USA.
    Measurement and interpretation of the ankle-brachial index: a scientific statement from the Ammerican Heart Association2012Ingår i: Circulation, ISSN 0009-7322, E-ISSN 1524-4539Artikel i tidskrift (Refereegranskat)
  • 300.
    Abraham, Abel
    Linköpings universitet, Institutionen för samhälls- och välfärdsstudier.
    Om konsten att sälja: En studie om hur företag försöker nå yngre konsumenter2010Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I dagens konsumtion och mediesamhälle bombarderas den unga individen av reklam. Det är utifrån detta förstårligt att man konstruerar en mur där man helt enkelt säger stopp till reklamen. Dock stoppar dtet ainte företagen som då försöker komma över denna mur  och på så sätt nå konsumenten.

    Syftet med studien är att belysa vilka uppfattningar marknadsförare har angående ungdomar som målgrupp och hur man utifrån det försöker nå denna målgrupp. Vilka tillvägagångssätt använder sig marknadsförarna av och hur övertygar de konsumenten?

    I analysen framkommer det tre diskurser är av väsentlig betydelse. Dessa diskurser tar upp den unga konsumentens situation och levnadsvillkor, retorikens betydelse för hur man påverkan konsumenterna och användandet av kommunikationsmedel för att nå målgruppen.

    Ladda ner fulltext (pdf)
    FULLTEXT01
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