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  • 201.
    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, p. 443-446Conference 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.

  • 202.
    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.

  • 203.
    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.

  • 204.
    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, p. 689-699Article 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.

  • 205.
    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, p. 99-108Conference 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, E-ISSN 1611-3349 ; 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: 2018-01-31
    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, p. 1047-1052Article 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.

    Keywords
    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: 2019-08-15Bibliographically 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, p. 327-362Article 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: 2019-08-15Bibliographically 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, p. 303-310Conference 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, E-ISSN 1611-3349 ; 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: 2018-02-12
    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, p. 2155-2170Article 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
    Keywords
    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: 2017-12-06Bibliographically approved
  • 206.
    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, p. 303-310Conference 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.

  • 207.
    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, p. 289-293Conference 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
    Keywords
    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, p. 1047-1052Article 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.

    Keywords
    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: 2019-08-15Bibliographically 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.

    Keywords
    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
  • 208.
    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, p. 2155-2170Article 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.

  • 209.
    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.

  • 210.
    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, p. 99-108Conference 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.

  • 211.
    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, p. 289-293Conference 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?

  • 212.
    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, p. 1047-1052Article 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.

  • 213.
    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, p. 818916-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.

  • 214.
    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, E-ISSN 1365-2346, Vol. 18, no 12, p. 823-828Article 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.

  • 215.
    Abioye, Ajibola I.
    et al.
    Brown Univ, RI 02912 USA.
    McDonald, Emily A.
    Brown Univ, RI 02912 USA.
    Park, Sangshin
    Brown Univ, RI 02912 USA; Univ Seoul, South Korea.
    Joshi, Ayush
    Brown Univ, RI 02912 USA.
    Kurtis, Jonathan D.
    Brown Univ, RI 02912 USA.
    Wu, Hannah
    Brown Univ, RI 02912 USA.
    Pond-Tor, Sunthorn
    Brown Univ, RI 02912 USA.
    Sharma, Surendra
    Brown Univ, RI 02912 USA; Women and Infants Hosp Rhode Isl, RI 02908 USA.
    Ernerudh, Jan
    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.
    Baltazar, Palmera
    Remedios Trinidad Romualdez Hosp, Philippines.
    Acosta, Luz P.
    Res Inst Trop Med, Philippines.
    Olveda, Remigio M.
    Res Inst Trop Med, Philippines.
    Tallo, Veronica
    Res Inst Trop Med, Philippines.
    Friedman, Jennifer F.
    Brown Univ, RI 02912 USA.
    Maternal, placental and cord blood cytokines and the risk of adverse birth outcomes among pregnant women infected with Schistosoma japonicum in the Philippines2019In: PLoS Neglected Tropical Diseases, ISSN 1935-2727, E-ISSN 1935-2735, Vol. 13, no 6, article id e0007371Article in journal (Refereed)
    Abstract [en]

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

  • 216.
    Abioye, Ajibola I.
    et al.
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Park, Sangshin
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Ripp, Kelsey
    Brown Univ, RI 02912 USA.
    McDonald, Emily A.
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Kurtis, Jonathan D.
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Wu, Hannah
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Pond-Tor, Sunthorn
    Rhode Isl Hosp, RI USA.
    Sharma, Surendra
    Brown Univ, RI 02912 USA; Women and Infants Hosp Rhode Isl, RI 02908 USA.
    Ernerudh, Jan
    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.
    Baltazar, Palmera
    Res Inst Trop Med, Philippines; Remedios Trinidad Romualdez Hosp, Philippines.
    Acosta, Luz P.
    Res Inst Trop Med, Philippines.
    Olveda, Remigio M.
    Res Inst Trop Med, Philippines.
    Tallo, Veronica
    Res Inst Trop Med, Philippines.
    Friedman, Jennifer F.
    Brown Univ, RI 02912 USA; Rhode Isl Hosp, RI USA; Rhode Isl Hosp, RI USA.
    Anemia of Inflammation during Human Pregnancy Does Not Affect Newborn Iron Endowment2018In: Journal of Nutrition, ISSN 0022-3166, E-ISSN 1541-6100, Vol. 148, no 3, p. 427-436Article in journal (Refereed)
    Abstract [en]

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

  • 217.
    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.

  • 218.
    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

  • 219.
    Abo Al Ahad, George
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Department of Science and Technology, Physics and Electronics.
    Gerzic, Denis
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Department of Science and Technology, Physics and Electronics.
    A Study on the Low Volatility Anomaly in the Swedish Stock Exchange Market: Modern Portfolio Theory2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

  • 220.
    Abo Al Ahad, George
    et al.
    Linköping University, Department of Management and Engineering, Production Economics.
    Salami, Abbas
    Linköping University, Department of Management and Engineering, Production Economics.
    Machine Learning for Market Prediction: Soft Margin Classifiers for Predicting the Sign of Return on Financial Assets2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

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

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

  • 221.
    Aboelnaga, Ahmed
    et al.
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Elmasry, Moustafa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Adly, Osama A.
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Elbadawy, Mohamed A.
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Abbas, Ashraf H.
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Abdelrahman, Islam
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Salah, Omar
    Plastic Surgery Unit, Surgery Department, Suez Canal University, Egypt.
    Steinvall, Ingrid
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery.
    Microbial cellulose dressing compared with silver sulphadiazine for the treatment of partial thickness burns: A prospective, randomised, clinical trial2018In: Burns, ISSN 0305-4179, E-ISSN 1879-1409, Vol. 44, no 8, p. 1982-1988Article in journal (Refereed)
    Abstract [en]

    Background

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

    Method

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

    Results

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

    Conclusion

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

  • 222. 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, E-ISSN 1873-3077, 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.

  • 223. 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, E-ISSN 1873-3077, Vol. 85, no 1-2, p. 109-119Article 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.

  • 224. 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, E-ISSN 1089-7550, Vol. 93, no 12, p. 9760-9768Article 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.

  • 225. 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, E-ISSN 1879-2731, Vol. 409, no 2, p. 233-242Article 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.

  • 226.
    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, p. 373-392Article 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.

  • 227.
    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, p. 1-14Article 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.

  • 228.
    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, p. 18-32Article 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.

  • 229.
    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, p. 237-248Article 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.

    Keywords
    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, p. 480-486Article 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.

    Keywords
    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: 2017-12-13Bibliographically 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, E-ISSN 1083-351X, Vol. 281, no 17, p. 11446-11449Article 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: 2017-12-13Bibliographically 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, E-ISSN 1090-2104, Vol. 350, no 3, p. 657-661Article 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.

    Keywords
    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: 2017-12-13Bibliographically approved
  • 230.
    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, E-ISSN 1090-2104, Vol. 350, no 3, p. 657-661Article 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.

  • 231.
    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, p. 237-248Article 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.

  • 232.
    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, E-ISSN 1083-351X, Vol. 281, no 17, p. 11446-11449Article 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.

  • 233.
    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, E-ISSN 1939-4675, Vol. 2, no 1-2, p. 155-177Article 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
    Keywords
    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: 2017-12-08Bibliographically 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, E-ISSN 1939-4675, Vol. 3, no 1, p. 53-70Article 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
    Keywords
    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: 2017-12-08Bibliographically 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, p. 277-301Article 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: 2017-12-08Bibliographically 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, E-ISSN 1746-0581, Vol. 2, no 3, p. 270-280Article 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
    Keywords
    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: 2017-12-08Bibliographically 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, p. 158-175Chapter 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, p. 287-294Chapter 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
    Keywords
    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, p. 170-179Conference 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
    Keywords
    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
  • 234.
    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, p. 277-301Article 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.

  • 235.
    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, E-ISSN 1939-4675, Vol. 3, no 1, p. 53-70Article 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.

  • 236.
    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, p. 158-175Chapter 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.

  • 237.
    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, E-ISSN 1746-0581, Vol. 2, no 3, p. 270-280Article 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.

  • 238.
    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, E-ISSN 1939-4675, Vol. 2, no 1-2, p. 155-177Article 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.

  • 239.
    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, p. 287-294Chapter 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.

  • 240.
    Abouzeedan, Adli
    et al.
    Innovation and Entrepreneurship, Department of Medicine Sahlgrenska Academy, University of Göteborg, Göteborg, Sweden.
    Hedner, Thomas
    Innovation and Entrepreneurship, Department of Medicine Sahlgrenska Academy, University of.
    Klofsten, Magnus
    Linköping University, Department of Management and Engineering, Project Innovations and Entrepreneurship. Linköping University, Faculty of Science & Engineering. Linköping University, HELIX Competence Centre.
    Innovation and entrepreneurship – new themes for new times2010In: Annals of Innovation & Entrepreneurship, ISSN 2000-7396, E-ISSN 2000-7396, ISSN ISSN 2000-7396, Vol. 1, no 1, p. 1-3Article in journal (Other academic)
    Abstract [en]

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

  • 241.
    Abouzeedan, Adli
    et al.
    Sahlgrenska Academy, University of Gothenburg, Sweden.
    Klofsten, Magnus
    Linköping University, Department of Management and Engineering, Project management, Innovations and Entrepreneurship . Linköping University, The Institute of Technology.
    Hedner, Thomas
    Sahlgrenska Academy, University of Gothenburg, Sweden.
    Analysis of a Swedish High Technology SME Using the Survival Index Value (SIV) Model2011In: Paper Sessions, Workshops and Special Meetings: The 56th ICSB World Conference, Stockholm, Sweden, 15th and 18th of June, ICSB , 2011, p. 170-179Conference 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.

  • 242.
    Abouzeedan, Adli
    et al.
    University of Gothenburg.
    Klofsten, Magnus
    Linköping University, Department of Management and Engineering, Project management, Innovations and Entrepreneurship . Linköping University, The Institute of Technology.
    Hedner, Thomas
    University of Gothenburg.
    Implementing the SIV Model on an Intensively Innovation-Oriented Firm: The Case of Autoadapt AB2012In: World Journal of Entrepreneurship, Management and Sustainable Development, ISSN 2042-5961, Vol. 8, no 2/3, p. 122-145Article in journal (Refereed)
    Abstract [en]

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

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

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

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

  • 243.
    Aboyans, Victor
    et al.
    Dupuytren University Hospital.
    Criqui, Michael
    University of California, USA.
    Abraham, Pierre
    University Hospital of Angers, France.
    Allison, Matthew
    University of California, USA.
    Creager, Mark
    Brigham and Women’s Hospital, USA.
    Diehm, Curt
    Karlsbad Clinic/University of Heidelberg, Germany.
    Fowkes, Gerry
    University of Edinburgh, UK.
    Hiatt, William
    University of Colorado, USA.
    Jönsson, Björn
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Lacroix, Philippe
    Limoges University, France.
    Marin, Benoit
    Limoges Teaching Hospital, France.
    McDermott, Mary
    Northwestern University,USA.
    Norgren, Lars
    University Hospital, Örebro, Sweden.
    Pande, Reena
    Brigham and Women’s Hospital, USA.
    Preux, Pierre-Marie
    University of Limoges, France.
    Stoffers, H.E.
    Maastricht University, Netherlands.
    Treat-Jacobsson, Diane
    University of Minnesota, USA.
    Measurement and interpretation of the ankle-brachial index: a scientific statement from the Ammerican Heart Association2012In: Circulation, ISSN 0009-7322, E-ISSN 1524-4539Article in journal (Refereed)
  • 244.
    Abraham, Abel
    Linköping University, Department of Social and Welfare Studies.
    Om konsten att sälja: En studie om hur företag försöker nå yngre konsumenter2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

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

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

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

  • 245.
    Abraham-Nordling, Mirna
    et al.
    Karolinska institutet.
    Persson, Bengt
    Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, The Institute of Technology.
    Nordling, Erik
    Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, The Institute of Technology.
    Model of the complex of Parathyroid hormone-2receptor and Tuberoinfundibular peptide of39 residues2010In: BMC Reseach Notes, ISSN 1756-0500, Vol. 3, no 270Article in journal (Refereed)
    Abstract [en]

    Background

    We aim to propose interactions between the parathyroid hormone-2 receptor (PTH2R) and its ligand the tuberoinfundibular peptide of 39 residues (TIP39) by constructing a homology model of their complex. The two related peptides parathyroid hormone (PTH) and parathyroid hormone related protein (PTHrP) are compared with the complex to examine their interactions.

    Findings

    In the model, the hydrophobic N-terminus of TIP39 is buried in a hydrophobic part of the central cavity between helices 3 and 7. Comparison of the peptide sequences indicates that the main discriminator between the agonistic peptides TIP39 and PTH and the inactive PTHrP is a tryptophan-phenylalanine replacement. The model indicates that the smaller phenylalanine in PTHrP does not completely occupy the binding site of the larger tryptophan residue in the other peptides. As only TIP39 causes internalisation of the receptor and the primary difference being an aspartic acid in position 7 of TIP39 that interacts with histidine 396 in the receptor, versus isoleucine/histidine residues in the related hormones, this might be a trigger interaction for the events that cause internalisation.

    Conclusions

    A model is constructed for the complex and a trigger interaction for full agonistic activation between aspartic acid 7 of TIP39 and histidine 396 in the receptor is proposed.

  • 246.
    Abrahams, M
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology.
    Eriksson, H
    Björnström, Karin
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, Anestesi.
    Eintrei, Christina
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, Anestesi.
    Effects of propofol on extracellular acidification rates in primary cortical cell cultures: application of silicon microphysiometry to anaesthesia.1999In: British Journal of Anaesthesia, ISSN 0007-0912, E-ISSN 1471-6771, Vol. 83, p. 567-569Article in journal (Refereed)
  • 247.
    Abrahams, M
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, Anestesi.
    Sjöberg, Folke
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Plastic Surgery, Hand Surgery and Burns. Östergötlands Läns Landsting, Reconstruction Centre, Department of Plastic Surgery, Hand surgery UHL.
    Oscarsson, Anna
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, MKC - Medicin och kirurgicentrum, Anestesi.
    Sundqvist, Tommy
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    The effects of human burn injury on urinary nitrate excretion. 1999In: Burns, ISSN 0305-4179, E-ISSN 1879-1409, Vol. 25, p. 29-33Article in journal (Refereed)
  • 248.
    Abrahamsson, Annelie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Capodanno, Alessandra
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Rzepecka, Anna
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping.
    Dabrosin, Charlotta
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Downregulation of tumor suppressive microRNAs in vivo in dense breast tissue of postmenopausal women2017In: OncoTarget, ISSN 1949-2553, E-ISSN 1949-2553, Vol. 8, no 54, p. 92134-92142Article in journal (Refereed)
    Abstract [en]

    Women with dense breast tissue on mammography are at higher risk of developing breast cancer but the underlying mechanisms are not well understood. De-regulation of microRNAs (miRNAs) has been associated with the onset of breast cancer. miRNAs in the extracellular space participate in the regulation of the local tissue microenvironment. Here, we recruited 39 healthy postmenopausal women attending their mammography-screen that were assessed having extreme dense or entirely fatty breasts (nondense). Microdialysis was performed in breast tissue and a reference catheter was inserted in abdominal subcutaneous fat for local sampling of extracellular compounds. Three miRNAs, associated with tumor suppression, miR-193b, miR-365a, and miR-452 were significantly down-regulated in dense breast tissue compared with nondense breast tissue. In addition, miR-452 exhibited significant negative correlations with several pro-inflammatory cytokines in vivo, which was confirmed in vitro by overexpression of miR-452 in breast cancer cells. No differences were found of miR-21, -29a, -30c, 146a, -148a, -203, or -451 in breast tissue and no miRs were different in plasma. Extracellular miRNAs may be among factors that should be included in studies of novel prevention strategies for breast cancer.

  • 249.
    Abrahamsson, Annelie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Dabrosin, Charlotta
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Tissue specific expression of extracellular microRNA in human breast cancers and normal human breast tissue in vivo2015In: OncoTarget, ISSN 1949-2553, E-ISSN 1949-2553, Vol. 6, no 26, p. 22959-22969Article in journal (Refereed)
    Abstract [en]

    Extracellular circulating microRNAs (miRNAs) have been suggested to be biomarkers for disease monitoring but data are inconsistent, one reason being that blood miRNA is of heterogeneous origin. Here, we sampled extracellular microRNAs locally in situ using microdialysis. Three different cohorts of women were included; postmenopausal women with ongoing breast cancer investigated within the cancer and in normal adjacent breast tissue, postmenopausal women investigated in their normal healthy breast and subcutaneous fat before and after six weeks of tamoxifen therapy, premenopausal women during the menstrual cycle. Samples were initially screened using TaqMan array cards with subsequently absolute quantification. 124 miRNA were expressed in microdialysates. After absolute quantifications extracellular miRNA-21 was found to be significantly increased in breast cancer. In addition, the levels were significantly higher in pre-menopausal breast tissue compared with postmenopausal. In breast tissue of pre-menopausal women miRNA-21 exhibited a cyclic variation during the menstrual cycle and in postmenopausal women six weeks of tamoxifen treatment decreased miRNA-21 suggesting that this miRNA may be important for breast carcinogenesis. None of these changes were found in plasma or microdialysates from subcutaneous fat. Our data revealed tissue specific changes of extracellular circulating miRNAs that would be otherwise unraveled using blood samples.

  • 250.
    Abrahamsson, Annelie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Oncology. Linköping University, Faculty of Health Sciences.
    Morad, Vivian
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Saarinen, Niina M
    Linköping University, Department of Clinical and Experimental Medicine, Oncology. Linköping University, Faculty of Health Sciences.
    Dabrosin, Charlotta
    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 Oncology UHL.
    Estradiol, Tamoxifen, and Flaxseed Alter IL-1 beta and IL-1Ra Levels in Normal Human Breast Tissue in Vivo2012In: Journal of Clinical Endocrinology and Metabolism, ISSN 0021-972X, E-ISSN 1945-7197, Vol. 97, no 11, p. E2044-E2054Article in journal (Refereed)
    Abstract [en]

    Introduction: Sex steroid exposure increases the risk of breast cancer by unclear mechanisms. Diet modifications may be one breast cancer prevention strategy. The proinflammatory cytokine family of IL-1 is implicated in cancer progression. IL-1Ra is an endogenous inhibitor of the proinflammatory IL-1 alpha and IL-1 beta. less thanbrgreater than less thanbrgreater thanObjective: The objective of this study was to elucidate whether estrogen, tamoxifen, and/or diet modification altered IL-1 levels in normal human breast tissue. less thanbrgreater than less thanbrgreater thanDesign and Methods: Microdialysis was performed in healthy women under various hormone exposures, tamoxifen therapy, and diet modifications and in breast cancers of women before surgery. Breast tissue biopsies from reduction mammoplasties were cultured. less thanbrgreater than less thanbrgreater thanResults: We show a significant positive correlation between estradiol and in vivo levels of IL-1 beta in breast tissue and abdominal sc fat, whereas IL-1Ra exhibited a significant negative correlation with estradiol in breast tissue. Tamoxifen or a dietary addition of 25 g flaxseed per day resulted in significantly increased levels of IL-1Ra in the breast. These results were confirmed in ex vivo culture of breast biopsies. Immunohistochemistry of the biopsies did not reveal any changes in cellular content of the IL-1s, suggesting that mainly the secreted levels were affected. In breast cancer patients, intratumoral levels of IL-1 beta were significantly higher compared with normal adjacent breast tissue. less thanbrgreater than less thanbrgreater thanConclusion: IL-1 may be under the control of estrogen in vivo and may be attenuated by antiestrogen therapy and diet modifications. The increased IL-1 beta in breast cancers of women strongly suggests IL-1 as a potential therapeutic target in breast cancer treatment and prevention.

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