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  • 151.
    Abdullah, M Ailieen
    et al.
    Royal Institute of Technology.
    Öhrwall Rönnbäck, Anna
    Linköping University, Department of Management and Engineering, Industrial Marketing and Industrial Economics. Linköping University, The Institute of Technology.
    Ölundh Sandström, Gunilla
    Royal Institute of Technology.
    Building Networks for Delivering Integrated Product-Service Offerings (IPSOs)2010In: Proceedings of 2nd CIRP IPS2 Conference 2010 - Industrial product-service systems -IPS², CIRP , 2010Conference paper (Refereed)
    Abstract [en]

    The paper describes the effect of forming business networks and collaborations for the purpose of developing an Integrated Product-Service Offering (IPSO) using the Product/Service Systems (PSS). The research method is an in-depth case study of a joint venture formed by four companies developing a new technology for chemical extraction from water sludge waste within the pulp and paper industry.

    Combining literature from PSS, network theories and collaborative product development, this paper puts forward the benefits for SMEs to collaborate in business networks and produce IPSOs when introducing a new technology in an emerging market. The case study shows that working towards the new market would not have been possible if each party acted individually or maintained their traditional buyer-supplieroperator roles, and that IPSOs can reduce the business risk.

  • 152.
    Abdul-Mumuni, Abdallah
    Linköping University, Department of Management and Economics.
    Conflict Resolution in West Africa: A Comparative Analysis of Sierra Leone and Liberia2005Independent thesis Advanced level (degree of Magister)Student thesis
    Abstract [en]

    This paper is a Master thesis for the Master’s program in International and European Relations in the Department of Management and Economics at Linköping University. As the title indicates, the aim of this thesis is to make a comparative analysis of the conflict resolution initiatives that were employed in the Sierra Leonean and Liberian conflicts. The research questions are:

    • What were the root causes and trajectories of the Sierra Leonean and Liberian conflicts?

    • What were the conflict resolution initiatives employed in resolving both conflicts?

    • Why did the Lome Peace Accord succeed in the case of Sierra Leone whilst the Abuja Peace Accord failed in bringing peace to Liberia?

    In order to answer the afore-mentioned questions and fulfil the aim of this paper, a qualitative research method has been chosen. The study is mainly based on secondary sources such as textbooks, official documents from ECOWAS and the UN, articles, magazines and newspapers as well as internet resources. In making the comparative analysis the Conflict Transformation Model as espoused by Kumar Rupesinghe has been utilized. This model has specifically helped in explaining the reasons why peace returned to Sierra Leone but eluded the people of Liberia for a long time. The conclusion drawn from the study is that a multi-track approach is required in dealing with conflicts in West Africa so that it would touch on the context of the conflict, the conflict structure, the intra-party as well as the inter- party divisions and the broader system of society and governance within the conflict area.

  • 153.
    Abe, Y
    et al.
    Tohoku University, Japan; .
    Hara, K
    Tohoku University, Japan; .
    Matsumoto, H
    Tohoku University, Japan; .
    Kobayashi-, J
    Tohoku University, Japan; .
    Sasada, H
    Tohoku University, Japan; .
    Ekwall, H
    Tohoku University, Japan; .
    Rodriguez-Martinez, Heriberto
    Swedish University of Agricultural Sciences; Sweden.
    Sato, E
    Tohoku University, Japan; .
    Feasibility of a nylon-mesh holder for vitrification of bovine germinal vesicle oocytes in subsequent production of viable blastocysts2005In: Biology of Reproduction, ISSN 0006-3363, E-ISSN 1529-7268, Vol. 72, no 6, 1416-1420 p.Article in journal (Refereed)
    Abstract [en]

    To improve the feasibility of nylon-mesh holder for vitrification of bovine cumulus-oocytes complexes (GV-COCs) having germinal vesicle, this study was conducted to demonstrate effects of sugars and protocol of exposure in vitrification on subsequent in vitro maturation, ultrastructural changes, and in vitro development in bovine immature oocytes after cryopreservation using nylon mesh. Before vitrification, GV-COCs were exposed to the cryoprotectant, which was composed of 40% (v/v) ethylene glycol, 18% (w/v) Ficoll-70, and 0.3 M sucrose (EFS40) or 0.3 M trehalose (EFT40), either by single step or in a stepwise way. The maturation rates in the stepwise exposure with EFS40 or EFT40 were significantly higher (P less than 0.05) compared with the corresponding rates in the single step. In the stepwise exposure, few abnormalities were observed compared with the single-step exposure, where most oocytes showed a highly vacuolated cytoplasm with many ruptured mitochondria. Cleavage rates in fertilized oocytes previously exposed stepwise to EFS40 or EFT40 were significantly higher than those exposed by the single-step procedure. The cleaved embryos derived from the stepwise exposure to EFS40 developed to blastocysts. After transfer of blastocysts derived from vitrified GV oocytes, a female calf was born. These results indicate that vitrification of large numbers of bovine GV-COCs using a nylon-mesh holder accompanied with stepwise exposure minimizes structural damage in organelles, resulting in yield of viable blastocysts following in vitro embryo production.

  • 154.
    Abebe, Meaza Eshetu
    et al.
    Linköping University, Department of Management and Engineering, Business Administration.
    Kalinina, Ekaterina
    Linköping University, Department of Management and Engineering, Business Administration.
    Coordination of inter-organizational projects within creative industries: A contextual perspective2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Inter-organizational projects have become common forms of organizing in various industries such as construction, advertising, music, film making etc. The unique structural nature of Inter-organizational projects coupled with the fact that they carried out through the participation of multiple organizations, raises issues of coordination. Particularly when it comes to creative industries, coordination is challenged by demand and transactional uncertainties. In order to understand how inter-organizational projects achieve coordination in such situations, it is important to study their interior processes putting in consideration their environmental context. 

    The aim of this research is to study how network embeddedness enhances coordination in inter-organizational projects within creative industries.

    Inter-organizational projects: are projects that are carried out through the collaboration of multiple legally independent organizations

    Inter-organizational networks: refer to sets of long-term ties among independent organizations that are engaged in continuous exchange relations.

    Embeddedness: refers to the continuous interaction of individuals, organizations, projects etc. with their environmental context.

    Macrocultures: refer to the shared beliefs, norms values rules and practices with in inter- organizational networks that guide members on their actions.

    A qualitative approach using a multiple comparative case study was conducted. Accordingly four projects chosen from creative industries were studied using both primary and secondary data.

    Macrocultures that are embedded inter-organizational networks facilitate coordination within inter-organizational projects. Further projects that differ in their constituents task nature, time duration and team composition relied on different types of embeddedness for coordination.

  • 155.
    Abednazari, Hossein
    et al.
    Linköping University, Department of Molecular and Clinical Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences.
    Xu, Junyang
    Linköping University, Department of Molecular and Clinical Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences.
    Millinger, Eva
    Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Respiratory Medicine. Linköping University, Faculty of Health Sciences.
    Brudin, Lars
    Department of Clinical Physiology, County Hospital, Kalmar, Sweden.
    Forsberg, Pia
    Linköping University, Department of Molecular and Clinical Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences.
    Nayeri, Fariba
    Linköping University, Department of Molecular and Clinical Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences.
    Hepatocyte growth factor is a better indicator of therapeutic response than C-reactive protein within the first day of treatment in pneumonia2006In: Chemotherapy, ISSN 0009-3157, E-ISSN 1421-9794, Vol. 52, no 5, 260-263 p.Article in journal (Refereed)
    Abstract [en]

    Acute bacterial infectious diseases are mostly treated empirically at admission before the culture results are available. According to the risk for serious complications in the case of therapeutic failure, it is important to evaluate the therapy results and change to a more appropriate antibiotic regime as soon as possible. In the present study, 40 patients with X-ray-verified community-acquired pneumonia were examined and blood specimens were collected before and within 24 h of treatment. Body temperature, C-reactive protein (CRP) and hepatocyte growth factor (HGF) were investigated. Thirty-two patients received an appropriate initial antibiotic therapy regarding clinical outcome, but in 8 patients the treatment was changed because of therapy failure. Changes of HGF levels after 18–24 h of treatment could predict the therapeutic results accurately in 38 of 40 cases (sensitivity 100%, specificity 94%, positive likelihood ratio 16.0). HGF was significantly better to predict therapy outcome than CRP (p < 0.0001).

  • 156.
    Abednazari, Hossin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. PEAS Institute, Linköping.
    Brudin, Lars
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Almroth, Gabriel
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Nephrology.
    Nilsson, Ingela
    Kalmar County Hospital, Sweden.
    Nayeri, Fariba
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases.
    Hepatocyte growth factor is a reliable marker for efficient anti-bacterial therapy within the first day of treatment2014In: Advances in Bioscience and Biotechnology, ISSN 2156-8456, E-ISSN 2156-8502, Vol. 5, no 10, 823-830 p.Article in journal (Refereed)
    Abstract [en]

    Rapid diagnosis and choice of appropriate antibiotic treatment might be life-saving in serious infectious diseases. Still the available markers that can evaluate and monitor the diagnosis and treatment are few. Hepatocyte growth factor (HGF) has been studied as a potent regenerative factor produced and released during injuries such as infectious diseases. Monitoring of HGF levels might predict therapy results better than C-reactive protein (CRP) within the first day of treatment in pneumonia. For further investigation of previous observations we aimed to study HGF as a first-day marker in over-representing infectious diseases in comparison to procalcitonin (PCT), CRP and body temperature. Fifty-one patients with community acquired infectious diseases were included consequently at admittance and the serum samples were collected before and within 18 - 24 hours of treatment. HGF levels decreased significantly in case of efficient antibiotic therapy and HGF was shown to be better than PCT, CRP and body temperature to evaluate treatment. In patients with pneumonia, monitoring of HGF was most reasonable. HGF might be used as a therapeutic marker within the first day of empiric antibiotic treatment during infection.

  • 157.
    Abela, Charles
    Linköping University, Department of Behavioural Sciences and Learning.
    Understanding the Dynamics of the Employability Agenda in Further Education Colleges in England: New Cross College - A Case Study2008Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study explores the dynamic of what happens within a further education college in order to develop an understanding of the cultures, systems and processes that are used to socially construct meaning around work and employability.  It is an inductive approach and is based on a case study of a further education college in South London.  The case study is analysed through the metaphor of an “extended family” and draws on social learning theory which is predicated on meaning and identity being created through social interaction (Wenger, 1998).  What has become apparent from being immersed within that extended family of the College, from interviews with staff and students, interacting in social activities, observing classes and reviewing many of its artefacts is perhaps an unremarkable conclusion.  The work of the family is not primarily about imparting a given set of skills (although that plays an important part) but in the formation of identity: “because learning transforms who we are and what we can do, it is an experience of identity” (Wenger, 1998, p. 215).  A major task for the College is to build self belief in developing the identity of learners and assist them to make new meaning so that they can transact effectively in economic life.  To the extent that one can examine and comprehend the organisational DNA of a further education college there are markers here, genes if you will, that can be passed across generations of learners that adapt and shift to survive in life beyond the boundaries of this community.  This study constructs a narrative around that research experience to respond to that primary research question about how the dynamics of the employability operate within a college.  The answer is partial, limited and perhaps only grabs at a corner of what is really going on within the College.  With those caveats and disclaimers what follows is the story of how a discourse takes root and flourishes within a learning community.  It points to the need to re-set the relationship between FE colleges and government to promote greater coherence between policy and practice.

  • 158.
    Abelius, M
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics. Linköping University, Faculty of Health Sciences.
    Ernerudh, Jan
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Immunology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Berg, Göran
    Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Gynecology and Obstetrics in Linköping.
    Matthiesen, Leif
    Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Gynecology and Obstetrics in Linköping.
    Nilsson, L J
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Jenmalm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics. Linköping University, Faculty of Health Sciences.
    Immunological interactions between mother and child: a characterisation of Th1-and Th2-like chemokines during pregnancy, postpartum and childhood in JOURNAL OF REPRODUCTIVE IMMUNOLOGY, vol 90, issue 2, pp 170-1712011In: JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Elsevier , 2011, Vol. 90, no 2, 170-171 p.Conference paper (Refereed)
    Abstract [en]

    n/a

  • 159.
    Abelius, Martina
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Immunological interactions between mother and child during pregnancy in relation to the development of allergic diseases in the offspring2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: Pregnancy and allergic disease have both been postulated as T-helper 2 (Th2) phenomena. Thus, the increased propensity of allergic mothers to mount Th2-responses might generate favourable effects on the maintenance of pregnancy, but might also be unfavorable, as fetal exposure to a strong Th2 environment could influence the immune development in the offspring to a Th2-like phenotype, favouring IgE production and possibly allergy development later in life. The influence of the intrauterine environment on the immunity and allergy development in the offspring needs to be further investigated.

    Aim: The aim of this thesis was to explore the Th1/Th2 balance in allergic and non-allergic women during pregnancy and its influence on the shaping of the Th1/Th2 profile in the neonate and the development of allergic diseases in the offspring.

    Material and methods: The study group included 20 women with and 36 women without allergic symptoms followed during pregnancy (gestational week 10-12, 15-16, 25, 35, 39) and 2 and 12 months postpartum, and their children followed from birth to 6 years of age. The circulating Th1-like chemokines CXCL9, CXCL10, CXCL11, Th2-like chemokines CCL17, CCL18 and CCL22, and the allergen-induced secretion of interleukin-4 (IL-4), IL-5, IL-10, IL-13, Interferon-γ (IFN-γ), CXCL10 and CCL17 were measured by Luminex and ELISA. The allergen-specific and total IgE levels were quantified using ImmunoCAP Technology. mRNA expression of Th1-, Th2-, Treg- and Th17-associated genes were measured by PCR arrays and real-time PCR.

    Results: We found that sensitised women with allergic symptoms had increased total IgE levels and birch- and cat-induced IL-5, IL-13 and CCL17 responses during pregnancy as compared with postpartum. The non-sensitised women without allergic symptoms had elevated cat-induced IL-5 and IL-13 responses and lower birch- and cat-induced IFN-γ during pregnancy, but similar IgE levels as compared with postpartum.

    Maternal total IgE levels during and after pregnancy correlated with cord blood (CB) IgE and CCL22 levels (regardless of maternal allergy status). Circulating CXCL11, CCL18 and CCL22 levels during pregnancy and postpartum correlated with the corresponding chemokine levels in the offspring at various time points during childhood. Maternal IL-5 expression in peripheral blood mononuclear cells (PBMC) was associated with neonatal Galectin-1, and placental p35 expression was negatively associated with neonatal Tbx21 expression. Increased mRNA expression of CCL22 in cord blood mononuclear cells (CBMC), and increased CCL17 and CCL22 levels in CB were observed in children later developing allergic symptoms and sensitisation as compared with children who did not. Development of allergic symptoms and sensitisation were associated with increased total IgE, CCL17, CCL18 and CCL22 levels during childhood.

    Conclusions: Maternal allergy was associated with a pronounced Th2 deviation during pregnancy, shown as increased total IgE levels and birch- and cat-induced IL-5, IL-13 and CCL17 responses during pregnancy, possibly exposing their fetuses to a particular strong Th2 environment during gestation.

    Correlations were shown between the maternal immunity during pregnancy and the offspring’s immunity at birth and later during childhood, indicating an interplay between the maternal and fetal immunity.

    Allergy development during the first 6 years of life was associated with a marked Th2 deviation at birth and a delayed down-regulation of this Th2-skewed immunity during childhood.

    List of papers
    1. Total and allergen-specific IgE levels during and after pregnancy in relation to maternal allergy
    Open this publication in new window or tab >>Total and allergen-specific IgE levels during and after pregnancy in relation to maternal allergy
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    2009 (English)In: JOURNAL OF REPRODUCTIVE IMMUNOLOGY, ISSN 0165-0378, Vol. 81, no 1, 82-88 p.Article in journal (Refereed) Published
    Abstract [en]

    Type 2 T-helper cell (Th2)-skewed immunity is associated with successful pregnancy and the ability to easily direct immune responses to a Th2-polarised profile may be an evolutionary benefit. The Th2-like immunity associated with allergic disease might generate favourable effects for the maintenance of pregnancy, but could also promote development of Th2-like immune responses and allergic disease in the offspring. The aim of this study was to explore, by using IgE as a stable proxy for Th2, the Th1/Th2 balance in allergic and non-allergic women by measuring allergen-specific and total IgE antibody levels in plasma during pregnancy and after delivery. Specific and total IgE antibody levels were determined by ImmunoCAP technology at five occasions during pregnancy (gestational weeks 10-12, 15-16, 25, 35 and 39), as well as at 2 and 12 months after delivery. Thirty-six women without and 20 women with allergic symptoms were included, of whom 13 were sensitised with allergic symptoms and 30 were non-sensitised without allergic symptoms. The levels of total IgE, but not allergen-specific IgE, were increased during early pregnancy when compared to 12 months after delivery in the sensitised women with allergic symptoms, but not in the non-sensitised women without allergic symptoms (pandlt;0.01). This increase in total IgE levels during early pregnancy only in the sensitised women with allergic symptoms indicates that allergy is associated with an enhanced Th2 deviation during pregnancy.

    Keyword
    Allergy, IgE, Phadiatop, Pregnancy, Th2
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-19894 (URN)10.1016/j.jri.2009.04.003 (DOI)
    Note

    Original Publication: Martina Sandberg, Anne Frykman, Yvonne Jonsson, Marie Persson, Jan Ernerudh, Göran Berg, Leif Matthiesen, Christina Ekerfelt and Maria Jenmalm, Total and allergen-specific IgE levels during and after pregnancy in relation to maternal allergy, 2009, JOURNAL OF REPRODUCTIVE IMMUNOLOGY, (81), 1, 82-88. http://dx.doi.org/10.1016/j.jri.2009.04.003 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/

    Available from: 2009-09-09 Created: 2009-08-14 Last updated: 2014-04-29Bibliographically approved
    2. High cord blood levels of the T-helper 2-associated chemokines CCL17 and CCL22 precede allergy development during the first 6 years of life
    Open this publication in new window or tab >>High cord blood levels of the T-helper 2-associated chemokines CCL17 and CCL22 precede allergy development during the first 6 years of life
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    2011 (English)In: Pediatric Research, ISSN 0031-3998, E-ISSN 1530-0447, Vol. 70, no 5, 495-500 p.Article in journal (Refereed) Published
    Abstract [en]

    Exposure to a strong T-helper 2 (Th2)-like environment during fetal development may promote allergy development. Increased cord blood (CB) levels of the Th2-associated chemokine CCL22 were associated with allergy development during the first 2 y of life. The aim of the present study was to determine whether CB Th1- and Th2-associated chemokine levels are associated with allergy development during the first 6 y of life, allowing assessment of respiratory allergic symptoms usually developing in this period. The CB levels of cytokines, chemokines, and total IgE were determined in 56 children of 20 women with allergic symptoms and 36 women without allergic symptoms. Total IgE and allergen-specific IgE antibody levels were quantified at 6, 12, 24 mo, and 6 y of age. Increased CB CCL22 levels were associated with development of allergic sensitization and asthma and increased CCL17 levels with development of allergic symptoms, including asthma. Sensitized children with allergic symptoms showed higher CB CCL17 and CCL22 levels and higher ratios between these Th2-associated chemokines and the Th1-associated chemokine CXCL10 than nonsensitized children without allergic symptoms. A pronounced Th2 deviation at birth, reflected by increased CB CCL17 and CCL22 levels, and increased CCL22/CXCL10 and CCL17/CXCL10 ratios might promote allergy development later in life.

    Keyword
    AD, atopic dermatitis, ARC, allergic rhinoconjunctivitis, CB, cord blood, SPT, skin prick test, Th, T-helper
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-74499 (URN)10.1203/PDR.0b013e31822f2411 (DOI)000296121100010 ()21796021 (PubMedID)
    Available from: 2012-01-30 Created: 2012-01-30 Last updated: 2014-04-29
    3. Th2-like chemokine levels are increased in allergic children and influenced by maternal immunity during pregnancy
    Open this publication in new window or tab >>Th2-like chemokine levels are increased in allergic children and influenced by maternal immunity during pregnancy
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    2014 (English)In: Pediatric Allergy and Immunology, ISSN 0905-6157, E-ISSN 1399-3038, Vol. 25, no 4, 387-393 p.Article in journal (Refereed) Published
    Abstract [en]

    Background: The influence of the intra-uterine environment on the immunity and allergy development in the offspring is unclear. We aimed to investigate (i) whether the pregnancy magnifies the Th2 immunity in allergic and non-allergic women, (ii) whether the maternal chemokine levels during pregnancy influenced the offspring’s chemokine levels during childhood and (iii) the relationship between circulating Th1/Th2-associated chemokines and allergy in mothers and children.

    Methods: The Th1-associated chemokines CXCL9, CXCL10, CXCL11, and the Th2- associated chemokines CCL17, CCL18 and CCL22 were quantified by Luminex and ELISA in 20 women with and 36 women without allergic symptoms at gestational week (gw) 10–12, 15–16, 25, 35, 39 and 2 and 12 months post-partum and in their children at birth, 6, 12, 24 months and 6 yr of age. Total IgE levels were measured using ImmunoCAP Technology.

    Results: The levels of the Th2-like chemokines were not magnified by pregnancy. Instead decreased levels were shown during pregnancy (irrespectively of maternal allergy status) as compared to post-partum. In the whole group, the Th1-like chemokine levels were higher at gw 39 than during the first and second trimester and post-partum. Maternal CXCL11, CCL18 and CCL22 levels during and after pregnancy correlated with the corresponding chemokines in the offspring during childhood. Increased CCL22 and decreased CXCL10 levels in the children were associated with sensitisation and increased CCL17 levels with allergic symptoms during childhood. Maternal chemokine levels were not associated with maternal allergic disease.

    Conclusions: Allergic symptoms and sensitisation were associated with decreased Th1-and increased Th2-associated chemokine levels during childhood, indicating a Th2 shift in the allergic children, possibly influenced by the maternal immunity during pregnancy.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2014
    Keyword
    Allergy; CCL17; CCL22; chemokines; pregnancy; Th2
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-106218 (URN)10.1111/pai.12235 (DOI)000338037100013 ()
    Available from: 2014-04-29 Created: 2014-04-29 Last updated: 2015-03-25Bibliographically approved
    4. Gene expression in placenta, peripheral and cord blood mononuclear cells from allergic and non-allergic women
    Open this publication in new window or tab >>Gene expression in placenta, peripheral and cord blood mononuclear cells from allergic and non-allergic women
    Show others...
    2014 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: The influence of maternal allergy on the development of immune responses and allergy in the offspring is not understood.

    Objective: To investigate (i) if maternal allergy influences the gene expression locally in placenta, systemically in peripheral blood mononuclear cells (PBMC) and fetally in cord blood mononuclear cells (CBMC), (ii) if the gene expression in the placenta and PBMC influences the gene expression in CBMC and (iii) how the gene expression at birth relates to allergy development during  childhood.

    Methods: A real-time PCR array was used to quantify forty immune regulatory genes in placenta, PBMC (gestational week 39) and in CBMC from 7 allergic and 12 non-allergic women and their offspring. Furthermore, quantitative real-time PCR was used to measure mRNA expression of Tbx21, GATA-3, Foxp3, RORC and CCL22 in CBMC, selected based on present PCR array results and previous protein findings in cord blood, in 13 children who developed and 11 children who did not develop allergy during childhood.

    Results: The gene expression profile in the placenta revealed a T-helper (Th) 2-/anti-inflammatory environment as compared with gene expression systemically, in PBMC. Maternal allergy was associated with increased expression of p35 in PBMC and CBMC and p40 in placenta. Placental p35 expression correlated with fetal Tbx21 expression (Rho=-0.88, p<0.001) and maternal IL-5 expression in PBMC with fetal Galectin-1 (Rho=0.91, p<0.001) expression. Allergy development in the children was preceded by high mRNA expression of the Th2-associated chemokine CCL22 at birth.

    Conclusion and clinical relevance: Gene expression locally and systemically during pregnancy influenced the offspring’s gene expression at birth, indicating an interplay between maternal and fetal immunity. Children developing allergy during childhood had an increased expression of the Th2-associated chemokine CCL22 at birth, indicating a Th2 skewing before disease onset. Maternal allergy was not associated with a Th2-dominance in placenta, PBMC or CBMC.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-106219 (URN)
    Available from: 2014-04-29 Created: 2014-04-29 Last updated: 2015-03-25Bibliographically approved
  • 160.
    Abelius, Martina
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Enke, Uta
    University Hospital Jena, Germany.
    Varosi, Frauke
    University Hospital Jena, Germany.
    Hoyer, Heike
    University Hospital Jena, Germany.
    Schleussner, Ekkehard
    University Hospital Jena, Germany.
    Jenmalm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Markert, Udo R.
    University Hospital Jena, Germany.
    Placental immune response to apple allergen in allergic mothers2014In: Journal of Reproductive Immunology, ISSN 0165-0378, E-ISSN 1872-7603, Vol. 106, 100-109 p.Article in journal (Refereed)
    Abstract [en]

    The immunological milieu in the placenta may be crucial for priming the developing foetal immune system. Early imbalances may promote the establishment of immune-mediated diseases in later life, including allergies. The initial exposure to allergens seems to occur in utero, but little is known about allergen-induced placental cytokine and chemokine release. The release of several cytokines and chemokines from placenta tissue after exposure to mast cell degranulator compound 48/80 or apple allergen in placentas from allergic and healthy mothers was to be analysed. Four placentas from women with apple allergy and three controls were applied in a placental perfusion model with two separate cotyledons simultaneously perfused with and without apple allergen (Mal d 1). Two control placentas were perfused with compound 48/80. In outflow, histamine was quantified spectrophotofluorometrically, IL-2, IL-4, IL-6, IL-10, TNF and IFN-gamma by a cytometric multiplex bead array and IL-13 and CXCL10, CXCL11, CCL17 and CCL22 with an in-house multiplex Luminex assay. Compound 48/80 induced a rapid release of histamine, CXCL10, CXCL11, CCL17 and CCL22, but not of the other factors. Apple allergen induced a time-dependent release of IL-6 and TNF, but not of histamine, in placentas of women with apple allergy compared with the unstimulated cotyledon. CCL17 levels were slightly increased after allergen stimulation in control placentas. Allergens can induce placental cytokines and chemokines distinctly in allergic and healthy mothers. These mediators may affect the prenatal development of the immune system and modify the risk of diseases related to immune disorders in childhood such as allergies.

  • 161.
    Abelius, Martina S
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics. Linköping University, Faculty of Health Sciences.
    Ernerudh, Jan
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Immunology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Berg, Göran
    Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Gynecology and Obstetrics in Linköping.
    Matthiesen, Leif
    Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Gynecology and Obstetrics in Linköping.
    Nilsson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Paediatrics in Linköping.
    Jenmalm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics. Linköping University, Faculty of Health Sciences.
    High cord blood levels of the T-helper 2-associated chemokines CCL17 and CCL22 precede allergy development during the first 6 years of life2011In: Pediatric Research, ISSN 0031-3998, E-ISSN 1530-0447, Vol. 70, no 5, 495-500 p.Article in journal (Refereed)
    Abstract [en]

    Exposure to a strong T-helper 2 (Th2)-like environment during fetal development may promote allergy development. Increased cord blood (CB) levels of the Th2-associated chemokine CCL22 were associated with allergy development during the first 2 y of life. The aim of the present study was to determine whether CB Th1- and Th2-associated chemokine levels are associated with allergy development during the first 6 y of life, allowing assessment of respiratory allergic symptoms usually developing in this period. The CB levels of cytokines, chemokines, and total IgE were determined in 56 children of 20 women with allergic symptoms and 36 women without allergic symptoms. Total IgE and allergen-specific IgE antibody levels were quantified at 6, 12, 24 mo, and 6 y of age. Increased CB CCL22 levels were associated with development of allergic sensitization and asthma and increased CCL17 levels with development of allergic symptoms, including asthma. Sensitized children with allergic symptoms showed higher CB CCL17 and CCL22 levels and higher ratios between these Th2-associated chemokines and the Th1-associated chemokine CXCL10 than nonsensitized children without allergic symptoms. A pronounced Th2 deviation at birth, reflected by increased CB CCL17 and CCL22 levels, and increased CCL22/CXCL10 and CCL17/CXCL10 ratios might promote allergy development later in life.

  • 162.
    Abelius, Martina S
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Janefjord, Camilla
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Ernerudh, Jan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Berg, Göran
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Matthiesen, Leif
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping. Helsingborg Hospital, Helsingborg.
    Duchén, Karel
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping.
    Nilsson, Lennart J
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Allergy Center.
    Jenmalm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    The Placental Immune Milieu is Characterized by a Th2- and Anti-Inflammatory Transcription Profile, Regardless of Maternal Allergy, and Associates with Neonatal Immunity2015In: American Journal of Reproductive Immunology, ISSN 1046-7408, E-ISSN 1600-0897, Vol. 73, no 5, 445-459 p.Article in journal (Refereed)
    Abstract [en]

    PROBLEM: How maternal allergy affects the systemic and local immunological environment during pregnancy and the immune development of the offspring is unclear.

    METHOD OF STUDY: Expression of 40 genes was quantified by PCR arrays in placenta, peripheral blood mononuclear cells (PBMC), and cord blood mononuclear cells (CBMC) from 7 allergic and 12 non-allergic women and their offspring.

    RESULTS: Placental gene expression was dominated by a Th2-/anti-inflammatory profile, irrespectively of maternal allergy, as compared to gene expression in PBMC. p35 expression in placenta correlated with fetal Tbx21 (ρ = -0.88, P < 0.001) and IL-5 expression in PBMC with fetal galectin1 (ρ = 0.91, P < 0.001). Increased expression of Th2-associated CCL22 in CBMC preceded allergy development.

    CONCLUSIONS: Gene expression locally and systemically during pregnancy was partly associated with the offspring's gene expression, possibly indicating that the immunological milieu is important for fetal immune development. Maternal allergy was not associated with an enhanced Th2 immunity in placenta or PBMC, while a marked prenatal Th2 skewing, shown as increased CCL22 mRNA expression, might contribute to postnatal allergy development.

  • 163.
    Abelius, Martina S
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Janefjord, Camilla
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Ernerudh, Jan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Berg, Göran
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Matthiesen, Leif
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Duchén, Karel
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Nilsson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Allergy Center.
    Jenmalm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Gene expression in placenta, peripheral and cord blood mononuclear cells from allergic and non-allergic women2014Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: The influence of maternal allergy on the development of immune responses and allergy in the offspring is not understood.

    Objective: To investigate (i) if maternal allergy influences the gene expression locally in placenta, systemically in peripheral blood mononuclear cells (PBMC) and fetally in cord blood mononuclear cells (CBMC), (ii) if the gene expression in the placenta and PBMC influences the gene expression in CBMC and (iii) how the gene expression at birth relates to allergy development during  childhood.

    Methods: A real-time PCR array was used to quantify forty immune regulatory genes in placenta, PBMC (gestational week 39) and in CBMC from 7 allergic and 12 non-allergic women and their offspring. Furthermore, quantitative real-time PCR was used to measure mRNA expression of Tbx21, GATA-3, Foxp3, RORC and CCL22 in CBMC, selected based on present PCR array results and previous protein findings in cord blood, in 13 children who developed and 11 children who did not develop allergy during childhood.

    Results: The gene expression profile in the placenta revealed a T-helper (Th) 2-/anti-inflammatory environment as compared with gene expression systemically, in PBMC. Maternal allergy was associated with increased expression of p35 in PBMC and CBMC and p40 in placenta. Placental p35 expression correlated with fetal Tbx21 expression (Rho=-0.88, p<0.001) and maternal IL-5 expression in PBMC with fetal Galectin-1 (Rho=0.91, p<0.001) expression. Allergy development in the children was preceded by high mRNA expression of the Th2-associated chemokine CCL22 at birth.

    Conclusion and clinical relevance: Gene expression locally and systemically during pregnancy influenced the offspring’s gene expression at birth, indicating an interplay between maternal and fetal immunity. Children developing allergy during childhood had an increased expression of the Th2-associated chemokine CCL22 at birth, indicating a Th2 skewing before disease onset. Maternal allergy was not associated with a Th2-dominance in placenta, PBMC or CBMC.

  • 164.
    Abelius, Martina S
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Lempinen, Esma
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Lindblad, Karin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Ernerudh, Jan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Berg, Göran
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Matthiesen, Leif
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Nilsson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Allergy Center.
    Jenmalm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Th2-like chemokine levels are increased in allergic children and influenced by maternal immunity during pregnancy2014In: Pediatric Allergy and Immunology, ISSN 0905-6157, E-ISSN 1399-3038, Vol. 25, no 4, 387-393 p.Article in journal (Refereed)
    Abstract [en]

    Background: The influence of the intra-uterine environment on the immunity and allergy development in the offspring is unclear. We aimed to investigate (i) whether the pregnancy magnifies the Th2 immunity in allergic and non-allergic women, (ii) whether the maternal chemokine levels during pregnancy influenced the offspring’s chemokine levels during childhood and (iii) the relationship between circulating Th1/Th2-associated chemokines and allergy in mothers and children.

    Methods: The Th1-associated chemokines CXCL9, CXCL10, CXCL11, and the Th2- associated chemokines CCL17, CCL18 and CCL22 were quantified by Luminex and ELISA in 20 women with and 36 women without allergic symptoms at gestational week (gw) 10–12, 15–16, 25, 35, 39 and 2 and 12 months post-partum and in their children at birth, 6, 12, 24 months and 6 yr of age. Total IgE levels were measured using ImmunoCAP Technology.

    Results: The levels of the Th2-like chemokines were not magnified by pregnancy. Instead decreased levels were shown during pregnancy (irrespectively of maternal allergy status) as compared to post-partum. In the whole group, the Th1-like chemokine levels were higher at gw 39 than during the first and second trimester and post-partum. Maternal CXCL11, CCL18 and CCL22 levels during and after pregnancy correlated with the corresponding chemokines in the offspring during childhood. Increased CCL22 and decreased CXCL10 levels in the children were associated with sensitisation and increased CCL17 levels with allergic symptoms during childhood. Maternal chemokine levels were not associated with maternal allergic disease.

    Conclusions: Allergic symptoms and sensitisation were associated with decreased Th1-and increased Th2-associated chemokine levels during childhood, indicating a Th2 shift in the allergic children, possibly influenced by the maternal immunity during pregnancy.

  • 165.
    Abelow, Alexis
    et al.
    University of Utah, Salt Lake City, USA.
    Persson, Kristin
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Jager, Edwin
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Berggren, Magnus
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Zharov, Ilya
    University of Utah, Salt Lake City, USA.
    Electroresponsive Nanoporous Membranes by Coating Anodized Alumina with Poly(3,4-ethylenedioxythiophone) and Polypyrrole2014In: Macromolecular materials and engineering (Print), ISSN 1438-7492, E-ISSN 1439-2054, Vol. 299, no 2, 190-197 p.Article in journal (Refereed)
    Abstract [en]

    Electrically-active nanoporous membranes are prepared by coating the surface of anodized alumina with electroactive polymers using vapor phase polymerization with four combinations of conjugated polymers and doping ions: poly(3,4-ethylenedioxythiophone) and polypyrrole, FeCl3 and FeTs3. The permeability of the polymer-coated membranes is measured as a function of the applied electric potential. A reversible three-fold increase is found in molecular flux of a neutral dye for membranes in oxidized state compared to that in the reduced state. After analyzing various factors that may affect the molecular transport through these membranes, it is concluded that the observed behavior results mostly from swelling/deswelling of the polymers and from the confinement of the polymers inside the nanopores.

  • 166.
    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
    Linköping University, Department of Clinical and Experimental Medicine, Oncology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Haematology UHL.
    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 countries2012In: Bone Marrow Transplantation, ISSN 0268-3369, E-ISSN 1476-5365, Vol. 47, no 3, 380-386 p.Article in journal (Refereed)
    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.

  • 167.
    Aberg, D
    et al.
    Royal Inst Technol, SE-16440 Kista, Sweden Linkoping Univ, Dept Phys & Measurement Technol, SE-58183 Linkoping, Sweden.
    Storasta, Liutauras
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Semiconductor Materials.
    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-SiC2001In: Materials Science Forum, Vols. 353-356, 2001, Vol. 353-3, 443-446 p.Conference paper (Refereed)
    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.

  • 168.
    Aberger, Martin
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Effects of Nonlinearities in Black Box Identification of an Industrial Robot2000Report (Other academic)
    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.

  • 169.
    Abeysekera, Ramanika
    Linköping University, Department of Computer and Information Science.
    Effects of system integration in an organization: A case study carried out in the photo and home electronics branch2005Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    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.

  • 170.
    Abidi, L.
    et al.
    Maastricht University, Netherlands.
    Oenema, A.
    Maastricht University, Netherlands.
    Nilsen, Per
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    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 Experts2016In: Prevention Science, ISSN 1389-4986, E-ISSN 1573-6695, Vol. 17, no 6, 689-699 p.Article in journal (Refereed)
    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.

  • 171.
    Abidin, Aysajan
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, The Institute of Technology.
    Authentication in Quantum Key Distribution: Security Proof and Universal Hash Functions2013Doctoral thesis, comprehensive summary (Other academic)
    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.

    List of papers
    1. New Universal Hash Functions
    Open this publication in new window or tab >>New Universal Hash Functions
    2012 (English)In: Lecture Notes in Computer Science, Vol. 7242 / [ed] Frederik Armknecht and Stefan Lucks, Springer Berlin Heidelberg , 2012, 99-108 p.Conference paper, Published paper (Refereed)
    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.

    Place, publisher, year, edition, pages
    Springer Berlin Heidelberg, 2012
    Series
    Lecture Notes in Computer Science, ISSN 0302-9743 (print), 1611-3349 (online) ; 7242
    National Category
    Other Electrical Engineering, Electronic Engineering, Information Engineering
    Identifiers
    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)
    Conference
    4th Western European Workshop on Research in Cryptology, WEWoRC 2011, Weimar, Germany, July 20-22, 2011
    Projects
    ICG QC
    Available from: 2012-10-18 Created: 2012-10-17 Last updated: 2016-08-31
    2. Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"
    Open this publication in new window or tab >>Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"
    2009 (English)In: International Journal of Quantum Information, ISSN 0219-7499, Vol. 7, no 5, 1047-1052 p.Article in journal (Refereed) 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.

    Keyword
    Quantum cryptography, quantum key distribution, authentication
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-20405 (URN)10.1142/S0219749909005754 (DOI)
    Projects
    ICG QC
    Available from: 2009-09-08 Created: 2009-09-07 Last updated: 2016-08-31Bibliographically approved
    3. Attacks on quantum key distribution protocols that employ non-ITS authentication
    Open this publication in new window or tab >>Attacks on quantum key distribution protocols that employ non-ITS authentication
    Show others...
    2016 (English)In: Quantum Information Processing, ISSN 1570-0755, E-ISSN 1573-1332, Vol. 15, no 1, 327-362 p.Article in journal (Refereed) 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.

    Place, publisher, year, edition, pages
    Springer Publishing Company, 2016
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-91260 (URN)10.1007/s11128-015-1160-4 (DOI)000372876800020 ()
    Projects
    ICG QC
    Note

    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]

    Available from: 2013-04-18 Created: 2013-04-18 Last updated: 2016-08-31Bibliographically approved
    4. On Security of Universal Hash Function Based Multiple Authentication
    Open this publication in new window or tab >>On Security of Universal Hash Function Based Multiple Authentication
    2012 (English)In: Lecture Notes in Computer Science, Vol. 7618 / [ed] Chim, Tat Wing and Yuen, Tsz Hon, 2012, 303-310 p.Conference paper, Published paper (Refereed)
    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.

    Series
    Lecture Notes in Computer Science, ISSN 0302-9743 (print), 1611-3349 (online) ; 7618
    National Category
    Engineering and Technology
    Identifiers
    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)
    Conference
    14th International Conference on Information and Communications Security, ICICS 2012, Hong Kong, China, October 29-31, 2012
    Projects
    ICG QC
    Available from: 2012-10-18 Created: 2012-10-18 Last updated: 2014-11-11
    5. Direct proof of security of Wegman-Carter authentication with partially known key
    Open this publication in new window or tab >>Direct proof of security of Wegman-Carter authentication with partially known key
    2014 (English)In: Quantum Information Processing, ISSN 1570-0755, E-ISSN 1573-1332, Vol. 13, no 10, 2155-2170 p.Article in journal (Refereed) 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.

    Place, publisher, year, edition, pages
    Springer, 2014
    Keyword
    Authentication, Strongly Universal hash functions, Partially known key, Trace distance, Universal Composability, Quantum Key Distribution.
    National Category
    Electrical Engineering, Electronic Engineering, Information Engineering
    Identifiers
    urn:nbn:se:liu:diva-91264 (URN)10.1007/s11128-013-0641-6 (DOI)000341842000002 ()
    Projects
    ICG QC
    Available from: 2013-04-18 Created: 2013-04-18 Last updated: 2016-08-31Bibliographically approved
  • 172.
    Abidin, Aysajan
    Linköping University, Department of Mathematics, Applied Mathematics. Linköping University, The Institute of Technology.
    Weaknesses of Authentication in Quantum Cryptography and Strongly Universal Hash Functions2010Licentiate thesis, comprehensive summary (Other academic)
    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.

    List of papers
    1. Special Properties of Strongly Universal2 Hash Functions Important in Quantum Cryptography
    Open this publication in new window or tab >>Special Properties of Strongly Universal2 Hash Functions Important in Quantum Cryptography
    2009 (English)In: AIP Conference Proceedings, ISSN 0094-243X, Foundations of Probability and Physics—5, Växjö, augusti 2008, New York: American Institute of Physics , 2009, Vol. 1101, 289-293 p.Conference paper, Published paper (Refereed)
    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?

    Place, publisher, year, edition, pages
    New York: American Institute of Physics, 2009
    Keyword
    Quantum cryptography, Quantum theory, Probability
    National Category
    Mathematics
    Identifiers
    urn:nbn:se:liu:diva-18738 (URN)10.1063/1.3109951 (DOI)
    Conference
    Foundations of Probability and Physics—5, Växjö, augusti 2008
    Projects
    ICG QC
    Available from: 2009-06-03 Created: 2009-06-03 Last updated: 2016-08-31
    2. Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"
    Open this publication in new window or tab >>Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"
    2009 (English)In: International Journal of Quantum Information, ISSN 0219-7499, Vol. 7, no 5, 1047-1052 p.Article in journal (Refereed) 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.

    Keyword
    Quantum cryptography, quantum key distribution, authentication
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-20405 (URN)10.1142/S0219749909005754 (DOI)
    Projects
    ICG QC
    Available from: 2009-09-08 Created: 2009-09-07 Last updated: 2016-08-31Bibliographically approved
    3. Lifetime of Authentication Using Encrypted Tags When the Encryption Key is Partially Known
    Open this publication in new window or tab >>Lifetime of Authentication Using Encrypted Tags When the Encryption Key is Partially Known
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Quantum cryptography is an unconditionally secure key growing technique provided that an unconditionally secure authentication protocol is combined with it. This paper is about the study of the lifetime of a message authentication scheme, where a message to be authenticated is first hashed by a secret–but fixed–Strongly Universal hash function then the output is encrypted with a one-time-pad key to generate a tag for the message. If the onetime-pad is completely secret, then the lifetime is exponential in the tag length. If, however, the one-time-pad key is partially known in each authentication round, as is the case in practical quantum key distribution protocols, then the picture is different; because the adversary’s partial knowledge of the one-time-pad key in each authentication round contributes to his/her ability to identify the secret hash function. We estimate the lifetime of this type of authentication. Here the parameters are the length of the key identifying the secret hash function and the amount of knowledge that Eve has on the one-time-pad. A theoretical estimate is presented, along with experimental results that support it.

    Keyword
    Quantum cryptography, quantum key distribution, authentication, strongly universal hash functions, lifetime
    National Category
    Mathematics
    Identifiers
    urn:nbn:se:liu:diva-57289 (URN)
    Projects
    ICG QC
    Available from: 2010-06-16 Created: 2010-06-16 Last updated: 2016-08-31
  • 173.
    Abidin, Aysajan
    Linköping University, Department of Electrical Engineering, Information Coding.
    On Security of Universal Hash Function Based Multiple Authentication2012In: Lecture Notes in Computer Science, Vol. 7618 / [ed] Chim, Tat Wing and Yuen, Tsz Hon, 2012, 303-310 p.Conference paper (Refereed)
    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.

  • 174.
    Abidin, Aysajan
    et al.
    Linköping University, Department of Mathematics, Applied Mathematics. Linköping University, The Institute of Technology.
    Larsson, Jan-Åke
    Linköping University, Department of Mathematics, Applied Mathematics. Linköping University, The Institute of Technology.
    Vulnerability of "A Novel Protocol-Authentication Algorithm Ruling out a Man-in-the-Middle Attack in Quantum Cryptography"2009In: International Journal of Quantum Information, ISSN 0219-7499, Vol. 7, no 5, 1047-1052 p.Article in journal (Refereed)
    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.

  • 175.
    Abidin, Aysajan
    et al.
    Linköping University, Department of Mathematics. Linköping University, The Institute of Technology.
    Larsson, Jan-Åke
    Linköping University, Department of Mathematics, Applied Mathematics. Linköping University, The Institute of Technology.
    Lifetime of Authentication Using Encrypted Tags When the Encryption Key is Partially KnownManuscript (preprint) (Other academic)
    Abstract [en]

    Quantum cryptography is an unconditionally secure key growing technique provided that an unconditionally secure authentication protocol is combined with it. This paper is about the study of the lifetime of a message authentication scheme, where a message to be authenticated is first hashed by a secret–but fixed–Strongly Universal hash function then the output is encrypted with a one-time-pad key to generate a tag for the message. If the onetime-pad is completely secret, then the lifetime is exponential in the tag length. If, however, the one-time-pad key is partially known in each authentication round, as is the case in practical quantum key distribution protocols, then the picture is different; because the adversary’s partial knowledge of the one-time-pad key in each authentication round contributes to his/her ability to identify the secret hash function. We estimate the lifetime of this type of authentication. Here the parameters are the length of the key identifying the secret hash function and the amount of knowledge that Eve has on the one-time-pad. A theoretical estimate is presented, along with experimental results that support it.

  • 176.
    Abidin, Aysajan
    et al.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, The Institute of Technology.
    Larsson, Jan-Åke
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, The Institute of Technology.
    Direct proof of security of Wegman-Carter authentication with partially known key2014In: Quantum Information Processing, ISSN 1570-0755, E-ISSN 1573-1332, Vol. 13, no 10, 2155-2170 p.Article in journal (Refereed)
    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.

  • 177.
    Abidin, Aysajan
    et al.
    Linköping University, Department of Mathematics, Applied Mathematics. Linköping University, The Institute of Technology.
    Larsson, Jan-Åke
    Linköping University, Department of Mathematics, Applied Mathematics. Linköping University, The Institute of Technology.
    Special Properties of Strongly Universal2 Hash Functions Important in Quantum Cryptography2009In: AIP Conference Proceedings, ISSN 0094-243X, Foundations of Probability and Physics—5, Växjö, augusti 2008, New York: American Institute of Physics , 2009, Vol. 1101, 289-293 p.Conference paper (Refereed)
    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?

  • 178.
    Abidin, Aysajan
    et al.
    Linköping University, Department of Electrical Engineering, Information Coding.
    Larsson, Jan-Åke
    Linköping University, Department of Electrical Engineering, Information Coding.
    New Universal Hash Functions2012In: Lecture Notes in Computer Science, Vol. 7242 / [ed] Frederik Armknecht and Stefan Lucks, Springer Berlin Heidelberg , 2012, 99-108 p.Conference paper (Refereed)
    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.

  • 179.
    Abidin, Aysajan
    et al.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, The Institute of Technology.
    Pacher, Christoph
    Austrian Institute of Technology, Austria.
    Lorünser, Thomas
    Austrian Institute of Technology, Austria.
    Larsson, Jan-Åke
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, The Institute of Technology.
    Peev, Momtchil
    Austrian Institute of Technology, Austria.
    Quantum cryptography and authentication with low key-consumption2011In: Proceedings of SPIE - The International Society for Optical Engineering, 2011, 818916- p.Conference paper (Refereed)
    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.

  • 180.
    Abildgaard, Lars
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, Anestesi.
    Aaro, Stig
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Orthopaedics and Sports Medicine.
    Lisander, Björn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, Anestesi.
    Limited effectiveness of intraoperative autotransfusion in major back surgery2001In: European Journal of Anaesthesiology, ISSN 0265-0215, Vol. 18, no 12, 823-828 p.Article in journal (Refereed)
    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.

  • 181.
    Abjanbekov, Aidyn
    et al.
    Linköping University, Department of Management and Economics.
    Alvarez Padilla, Ana Elena
    Linköping University, Department of Management and Economics.
    From Knowledge Transfer to Knowledge Translation: Case Study of a Telecom Consultancy2004Independent thesis Advanced level (degree of Magister)Student thesis
    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.

  • 182.
    Ablahad, Marlen
    Linköping University, Department of Religion and Culture.
    Bära Sorg Föra Liv: En studie om begravningsritualer bland syrianer/assyrier i hemlandet och i Sverige.2005Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    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

  • 183. 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
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Erikssion, M.
    Experimental evidence for a dissociation mechanism in NH3 detection with MIS field-effect devices2003In: Sensors and actuators. B, Chemical, ISSN 0925-4005, Vol. 89, no 1-2Article in journal (Refereed)
    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.

  • 184. Abom, A.E.
    et al.
    Comini, E.
    Sberveglieri, G.
    Hultman, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Eriksson, Mats
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Thin oxide films as surface modifiers of MIS field effect gas sensors2002In: Sensors and actuators. B, Chemical, ISSN 0925-4005, Vol. 85, no 1-2, 109-119 p.Article in journal (Refereed)
    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.

  • 185. 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
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Eriksson, Mats
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Characterization of the metal-insulator interface of field-effect chemical sensors2003In: Journal of Applied Physics, ISSN 0021-8979, Vol. 93, no 12, 9760-9768 p.Article in journal (Refereed)
    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.

  • 186. Abom, A.E.
    et al.
    Persson, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Hultman, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Eriksson, Mats
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Influence of gate metal film growth parameters on the properties of gas sensitive field-effect devices2002In: Thin Solid Films, ISSN 0040-6090, Vol. 409, no 2, 233-242 p.Article in journal (Refereed)
    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.

  • 187.
    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
    Linköping University, The Tema Institute, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences. North West University, South Africa.
    Occurrence, abundance and distribution of benthic macroinvertebrates in the Nyando River catchment, Kenya2015In: African Journal of Aquatic Science, ISSN 1608-5914, E-ISSN 1727-9364, Vol. 40, no 4, 373-392 p.Article in journal (Refereed)
    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.

  • 188.
    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
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Impacts of pesticides on human health and environment in the River Nyando catchment, Kenya2014In: International Journal of Humanities, Arts, Medicine and Sciences, ISSN 2348-0521, Vol. 2, no 3, 1-14 p.Article in journal (Other academic)
    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.

  • 189.
    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
    Linköping University, The Tema Institute, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Nkedi-Kizza, Peter
    University of Florida, USA.
    Organochlorine pesticide residue levels in soil from the Nyando River catchment, Kenya2015In: Africa Journal of Physical Sciences, ISSN 2313-3317, Vol. 2, no 1, 18-32 p.Article in journal (Refereed)
    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.

  • 190.
    Aboulaich, Nabila
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Expanding role of caveolae in control of adipocyte metabolism: proteomics of caveolae2006Doctoral thesis, comprehensive summary (Other academic)
    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.

    List of papers
    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
    Open this publication in new window or tab >>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 (English)In: The Biochemical journal, ISSN 1470-8728, Vol. 383, no Pt 2, 237-248 p.Article in journal (Refereed) 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.

    Keyword
    Caveolae, human adipocyte, MS, PEST sequence, polymerase I and transcript release factor (PTRF), proteolysis
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-19145 (URN)10.1042/BJ20040647 (DOI)15242332 (PubMedID)
    Available from: 2009-06-12 Created: 2009-06-12 Last updated: 2009-06-12Bibliographically approved
    2. N-terminal processing and modifications of caveolin-1 in caveolae from human adipocytes
    Open this publication in new window or tab >>N-terminal processing and modifications of caveolin-1 in caveolae from human adipocytes
    Show others...
    2004 (English)In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 320, no 2, 480-486 p.Article in journal (Refereed) 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.

    Keyword
    Human adipocyte, Caveolin-1; Caveolae, Protein phosphorylation, N-terminal acetylation, Mass spectrometry
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-19146 (URN)10.1016/j.bbrc.2004.05.196 (DOI)15219854 (PubMedID)
    Available from: 2009-06-12 Created: 2009-06-12 Last updated: 2016-03-09Bibliographically approved
    3. Hormonal control of reversible translocation of perilipin B to the plasma membrane in primary human adipocytes
    Open this publication in new window or tab >>Hormonal control of reversible translocation of perilipin B to the plasma membrane in primary human adipocytes
    2006 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, Vol. 281, no 17, 11446-11449 p.Article in journal (Refereed) 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.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-19147 (URN)10.1074/jbc.C500461200 (DOI)16527823 (PubMedID)
    Available from: 2009-06-12 Created: 2009-06-12 Last updated: 2009-06-12Bibliographically approved
    4. Association and insulin regulated translocation of hormone-sensitive lipase with PTRF
    Open this publication in new window or tab >>Association and insulin regulated translocation of hormone-sensitive lipase with PTRF
    2006 (English)In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, Vol. 350, no 3, 657-661 p.Article in journal (Refereed) 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.

    Keyword
    Hormone-sensitive lipase, Polymerase I and transcript release factor, Adipocyte, Human, Insulin, Translocation, Protein complex, Caveolae, Lipid metabolism, Transcriptional control
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-19148 (URN)10.1016/j.bbrc.2006.09.094 (DOI)17026959 (PubMedID)
    Available from: 2009-06-12 Created: 2009-06-12 Last updated: 2009-07-06Bibliographically approved
  • 191.
    Aboulaich, Nabila
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Ortegren, Unn
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Vener, Alexander V
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Strålfors, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Association and insulin regulated translocation of hormone-sensitive lipase with PTRF2006In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, Vol. 350, no 3, 657-661 p.Article in journal (Refereed)
    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.

  • 192.
    Aboulaich, Nabila
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Vainonen, Julia P
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Strålfors, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Vener, Alexander V
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Vectorial proteomics reveal targeting, phosphorylation and specific fragmentation of polymerase I and transcript release factor (PTRF) at the surface of caveolae in human adipocytes2004In: The Biochemical journal, ISSN 1470-8728, Vol. 383, no Pt 2, 237-248 p.Article in journal (Refereed)
    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.

  • 193.
    Aboulaich, Nabila
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Vener, Alexander V
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Strålfors, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Hormonal control of reversible translocation of perilipin B to the plasma membrane in primary human adipocytes2006In: Journal of Biological Chemistry, ISSN 0021-9258, Vol. 281, no 17, 11446-11449 p.Article in journal (Refereed)
    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.

  • 194.
    Abouzeedan, Adli
    Linköping University, Department of Management and Engineering. Linköping University, The Institute of Technology.
    SME Performance and Its Relationship to Innovation2011Doctoral thesis, comprehensive summary (Other academic)
    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.

    List of papers
    1. Typology Analysis of Performance Models of Small and Medium-Size Enterprises (SMEs)
    Open this publication in new window or tab >>Typology Analysis of Performance Models of Small and Medium-Size Enterprises (SMEs)
    2004 (English)In: International Journal of Entrepreneurship, ISSN 1099-9264, Vol. 2, no 1-2, 155-177 p.Article in journal (Refereed) 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.

    Place, publisher, year, edition, pages
    SpringerLink, 2004
    Keyword
    small and medium-size enterprises - survival index value - SIV® model - Z-scores - neural networks
    National Category
    Economics and Business
    Identifiers
    urn:nbn:se:liu:diva-71336 (URN)10.1023/B:JIEN.0000026911.03396.2d (DOI)
    Available from: 2011-10-12 Created: 2011-10-12 Last updated: 2011-11-21Bibliographically approved
    2. ASPEM as the New Topographic Analysis Tool for Small and Medium-Sized Enterprises (SMEs) Performance Models Utilization
    Open this publication in new window or tab >>ASPEM as the New Topographic Analysis Tool for Small and Medium-Sized Enterprises (SMEs) Performance Models Utilization
    2005 (English)In: International Journal of Entrepreneurship, ISSN 1099-9264, Vol. 3, no 1, 53-70 p.Article in journal (Refereed) 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.

    Place, publisher, year, edition, pages
    SpringerLink, 2005
    Keyword
    Arena of SMEs performance models, ASPEM - SIV® model, Zeta-scores, ZETA-scores, neural networks, stochastic theories, hazard modeling
    National Category
    Economics and Business
    Identifiers
    urn:nbn:se:liu:diva-71337 (URN)10.1007/s10843-005-0305-4 (DOI)
    Available from: 2011-10-12 Created: 2011-10-12 Last updated: 2011-11-21Bibliographically approved
    3. Analysis of Swedish Fishery Company Using SIV® Model: A Case Study
    Open this publication in new window or tab >>Analysis of Swedish Fishery Company Using SIV® Model: A Case Study
    2004 (English)In: Journal of Enterprising Culture, ISSN 0218-4958, Vol. 12, no 4, 277-301 p.Article in journal (Refereed) 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.

    Place, publisher, year, edition, pages
    World Scientific Publishing Co., 2004
    National Category
    Economics and Business
    Identifiers
    urn:nbn:se:liu:diva-71340 (URN)10.1142/S0218495804000154 (DOI)
    Available from: 2011-10-12 Created: 2011-10-12 Last updated: 2011-11-21Bibliographically approved
    4. Innovation Balance Matrix: an application in the Arab countries
    Open this publication in new window or tab >>Innovation Balance Matrix: an application in the Arab countries
    2006 (English)In: World Review of Entrepreneurship, Management and Sustainable Development, ISSN 1746-0573, Vol. 2, no 3, 270-280 p.Article in journal (Refereed) 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.

    Place, publisher, year, edition, pages
    Inderscience Enterprises Limited, 2006
    Keyword
    Human capital; financial capital; system capital; innovation capital; innovation balance matrix; IBAM; Arab countries; Middle East; entrepreneurship.
    National Category
    Economics and Business
    Identifiers
    urn:nbn:se:liu:diva-71341 (URN)10.1504/WREMSD.2006.009893 (DOI)
    Available from: 2011-10-12 Created: 2011-10-12 Last updated: 2011-11-21Bibliographically approved
    5. Entrepreneurial policies and the innovation balance matrix: the case of the Arab countries
    Open this publication in new window or tab >>Entrepreneurial policies and the innovation balance matrix: the case of the Arab countries
    2007 (English)In: Science,Technology and Sustainability in the Middle East and North Africa: Section III: Science Technology and Innovation / [ed] Allam Ahmed, Inderscience Enterprises Limited , 2007, 158-175 p.Chapter in book (Refereed)
    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.

    Place, publisher, year, edition, pages
    Inderscience Enterprises Limited, 2007
    Series
    Globalisation, Technology and Sustainable Development Book Series
    National Category
    Economics and Business
    Identifiers
    urn:nbn:se:liu:diva-71342 (URN)0-907776-30-2 (ISBN)0-907776-32-9 (ISBN)
    Available from: 2011-10-12 Created: 2011-10-12 Last updated: 2011-11-21Bibliographically approved
    6. Managing Innovation in a Globalised Economy: Defining the Open Capital
    Open this publication in new window or tab >>Managing Innovation in a Globalised Economy: Defining the Open Capital
    2009 (English)In: 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, 287-294 p.Chapter in book (Refereed)
    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.

    Place, publisher, year, edition, pages
    World Association for Sustainable Development, 2009
    Keyword
    Open Capital, Human Capital, Financial Capital, System Capital, Innovation Capital, Open Innovation, Open Innovation Management
    National Category
    Economics and Business
    Identifiers
    urn:nbn:se:liu:diva-71344 (URN)978-1-907106-05-7 (ISBN)
    Available from: 2011-10-12 Created: 2011-10-12 Last updated: 2011-11-21Bibliographically approved
    7. Analysis of a Swedish High Technology SME Using the Survival Index Value (SIV) Model
    Open this publication in new window or tab >>Analysis of a Swedish High Technology SME Using the Survival Index Value (SIV) Model
    2011 (English)In: Paper Sessions, Workshops and Special Meetings: The 56th ICSB World Conference, Stockholm, Sweden, 15th and 18th of June, ICSB , 2011, 170-179 p.Conference paper, Published paper (Refereed)
    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.

    Place, publisher, year, edition, pages
    ICSB, 2011
    Keyword
    small and medium-sized enterprises, SMEs, performance evaluation models, SIV model
    National Category
    Economics and Business
    Identifiers
    urn:nbn:se:liu:diva-71345 (URN)978-0-9819028-3-8 (ISBN)0-9819028-3-9 (ISBN)
    Conference
    ICSB 2011 World Conference Date: June 15-18, 2011, Stockholm Waterfront Congress Center, Stockholm, Sweden
    Available from: 2011-10-12 Created: 2011-10-12 Last updated: 2016-05-04Bibliographically approved
  • 195.
    Abouzeedan, Adli
    et al.
    Amana Commercial Consultants, Partille, Sweden.
    Busler, Michael
    Pennsylvania State University USA.
    Analysis of Swedish Fishery Company Using SIV® Model: A Case Study2004In: Journal of Enterprising Culture, ISSN 0218-4958, Vol. 12, no 4, 277-301 p.Article in journal (Refereed)
    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.

  • 196.
    Abouzeedan, Adli
    et al.
    Amana Commercial Consultants, Partille, Sweden.
    Busler, Michael
    Pennsylvania State University, Great Valley Graduate Center, Malvern, PA 19355, USA.
    Typology Analysis of Performance Models of Small and Medium-Size Enterprises (SMEs)2004In: International Journal of Entrepreneurship, ISSN 1099-9264, Vol. 2, no 1-2, 155-177 p.Article in journal (Refereed)
    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.

  • 197.
    Abouzeedan, Adli
    et al.
    Amana Commercial Consultants, Partille, Sweden.
    Busler, Michael
    Rowan University, 201 Mullica Hill Road, Glassboro, NJ 08028, USA.
    Innovation Balance Matrix: an application in the Arab countries2006In: World Review of Entrepreneurship, Management and Sustainable Development, ISSN 1746-0573, Vol. 2, no 3, 270-280 p.Article in journal (Refereed)
    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.

  • 198.
    Abouzeedan, Adli
    et al.
    Amana Commercial Consultants, Partille, Sweden.
    Busler, Michael
    Pennsylvania State University, Great Valley Graduate Center, Malvern, PA 19355.
    ASPEM as the New Topographic Analysis Tool for Small and Medium-Sized Enterprises (SMEs) Performance Models Utilization2005In: International Journal of Entrepreneurship, ISSN 1099-9264, Vol. 3, no 1, 53-70 p.Article in journal (Refereed)
    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.

  • 199.
    Abouzeedan, Adli
    et al.
    Amana Commercial Consultants, Partille, Sweden.
    Busler, Michael
    Rowan University, 201 Mullica Hill Road, Glassboro, NJ 08028, USA.
    Entrepreneurial policies and the innovation balance matrix: the case of the Arab countries2007In: Science,Technology and Sustainability in the Middle East and North Africa: Section III: Science Technology and Innovation / [ed] Allam Ahmed, Inderscience Enterprises Limited , 2007, 158-175 p.Chapter in book (Refereed)
    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.

  • 200.
    Abouzeedan, Adli
    et al.
    University of Gothenburg, Sweden.
    Busler, Michael
    The Richard Stockton College of New Jersey, USA.
    Hedner, Thomas
    University of Gothenburg, Sweden.
    Managing Innovation in a Globalised Economy: Defining the Open Capital2009In: 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, 287-294 p.Chapter in book (Refereed)
    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.

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