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  • 51.
    Aasa, Jenny
    et al.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Vryonidis, Efstathios
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Abramsson-Zetterberg, Lilianne
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Internal Doses of Glycidol in Children and Estimation of Associated Cancer Risk2019In: Toxics, ISSN 2305-6304, Vol. 7, no 1, article id 7Article in journal (Refereed)
    Abstract [en]

    The general population is exposed to the genotoxic carcinogen glycidol via food containing refined edible oils where glycidol is present in the form of fatty acid esters. In this study, internal (in vivo) doses of glycidol were determined in a cohort of 50 children and in a reference group of 12 adults (non-smokers and smokers). The lifetime in vivo doses and intakes of glycidol were calculated from the levels of the hemoglobin (Hb) adduct N-(2,3-dihydroxypropyl)valine in blood samples from the subjects, demonstrating a fivefold variation between the children. The estimated mean intake (1.4 mu g/kg/day) was about two times higher, compared to the estimated intake for children by the European Food Safety Authority. The data from adults indicate that the non-smoking and smoking subjects are exposed to about the same or higher levels compared to the children, respectively. The estimated lifetime cancer risk (200/10(5)) was calculated by a multiplicative risk model from the lifetime in vivo doses of glycidol in the children, and exceeds what is considered to be an acceptable cancer risk. The results emphasize the importance to further clarify exposure to glycidol and other possible precursors that could give a contribution to the observed adduct levels.

  • 52.
    Aasi, Parisa
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Information Technology Governance: The Role of Organizational Culture and Structure2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Information Technology Governance (ITG) is among the most important challenges for the managers today. IT is not anymore just a supportive tool but also a strategic driver for the businesses. In the dynamic and competitive world of today, it is crucial for organizations to know how to govern IT rather than just to use it. IT governance deals with specifying responsibilities and decision rights to encourage the desirable behaviour from IT and generate value from IT investments. IT governance can impact the overall performance of organizations, however there are still difficulties in understanding IT governance and the factors that may influence it.

    Organizational culture and structure are among the factors that have significant influence on many issues in an organization. According to previous research, organizational culture and structure need to be considered when implementing IT governance. However, there is a lack of research focusing on how organizational culture and structure can influence IT governance performance and implementation. Thus, the main research question addressed in this thesis is: How are organizational culture and structure related to IT governance? To address this question, this research has performed literature reviews and conducted case studies to investigate the role of organizational culture and structure on IT governance. As the first step, the previous literature was reviewed to find the gaps in the research on culture and IT governance. As the next step, four case studies were conducted to explore the influence of organizational culture and structure on IT governance. Two case studies have investigated the relation between organizational structure and IT governance implementation and performance in large organizations; and two other case studies investigated on how different types of organizational culture influence IT governance performance outcomes.

    The results of this research respond to the research question by specifying the role of culture in IT governance through a categorization of prior research both from research and practice perspectives; specifying the influence of different organizational culture types on IT governance performance outcomes in different organizations; and by specifying IT organizational structure relationship with IT governance performance outcomes and IT governance implementation.

    The research presented in this thesis provides both theoretical and empirical contributions to the IT governance research and practice.

  • 53.
    Aasi, Parisa
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Organizational Culture and Structure Influence on Information Technology Governance2016Licentiate thesis, comprehensive summary (Other academic)
  • 54.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Nunes, Ivan
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Hodosi, Georg
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Does Organizational Culture Matter in IT Outsourcing Relationships?2015In: Proceedings of the 48th Annual Hawaii International Conference on System Sciences (HICSS-48), IEEE Computer Society, 2015, p. 4691-4699Conference paper (Refereed)
  • 55.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Nunes, Ivan
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Hodosi, Georg
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    The impact of different organizational cultures on IT outsourcing relationship management2013In: International Journal of Innovation in the Digital Economy, ISSN 1947-8305, Vol. 4, no 2, p. 50-66Article in journal (Refereed)
    Abstract [en]

    Globalization has affected the organizations in many aspects such as structure, architecture, internal/external strategies and sourcing management. Outsourcing is one of the recent business strategies used to provide IT needs via external agents. The relationship between the service buyer and provider companies is a constituent playing a significant role in IT outsourcing success or failure. This research has a focus on the influence of organizational culture of buyer companies on the specific factors of trust, cooperation, communication and commitment in their relationship with the IT service provider. Two explorative case studies are done in global companies using ITO which revealed the presence of organizational culture effect. Particularly, being innovative, having open discussion as an organizational culture and looking for extending contracts with providers as a strategy, appeared as the major difference between the two cases organizational culture; which influences the studied factors of ITO relationship in this research.

  • 56.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Facing The Digitalization Challenge: Why Organizational Culture Matters and How It Influences IT Governance Performance2017In: Information Systems Development: Advances in Methods, Tools and Management: Proceedings / [ed] N. Paspallis, M. Raspopoulos, C. Barry, M. Lang, H. Linger, C. Schneider, Association for Information Systems, 2017Conference paper (Refereed)
    Abstract [en]

    Today it is not possible for the companies to compete without having IT as a strategic driver. That is why IT governance becomes crucial for managers to bring the most value from IT to the business. Additionally organizational culture is an important factor and often blamed when IT governance projects fail. However little in-depth research investigated how the organizational culture changes can improve the IT governance performance. This research is a case study of the IT department of a large company attempting to improve the IT governance while facing the digitalization challenge. In this case the IT department has an organizational culture change journey seeking to improve the IT governance performance. The results indicate that the initial clan culture orientation of the IT department has led to a successful IT governance performance in cost-effective use of IT. Furthermore, adhocracy is identified as preferred culture for improving IT governance for growth.

  • 57.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Han, Shengnan
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Culture Influence on IT Governance: What We Have Learned?2017In: Organizational Culture and Behavior: Concepts, Methodologies, Tools, and Applications, IGI Global, 2017, no 2017Chapter in book (Other academic)
    Abstract [en]

    Managers face enormous challenges today to plan the decision rights and responsibilities in order to reach desired IT behaviors which are aligned with business objectives of organizations. This is known as IT governance and is ranked as one of the firms' top concerns. Not surprisingly, it is crucial for organizations to find the affecting factors on IT governance and solve the problems associated with it. Culture in national, organizational or group level is an affecting factor in organizations that can play a role in IT governance and this role is rarely explored in academic research. This paper provides a literature review investigating the influence of culture on IT governance. The research purpose is to identify how culture and IT governance in the companies can be linked together and promote this area for future research. The literature review is done systematically and the findings are classified by using an IT governance framework with three main components of structures, processes and relational mechanisms. The results indicate there is an influence from national and organizational culture on IT governance. However, the number of studies is very few and there is still a lack of knowledge on how culture can influence IT governance. This research calls upon a further research on culture impact on achieving an effective IT governance implementation in organizations.

  • 58.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Han, Shengnan
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Culture Influence on IT Governance: What We Have Learned?2014In: International Journal of IT - Business Alignment and Governance, ISSN 1947-9611, E-ISSN 1947-962X, Vol. 5, no 1, article id 3Article in journal (Other academic)
    Abstract [en]

    Managers face enormous challenges today to plan the decision rights and responsibilities in order to reach desired IT behaviors which are aligned with business objectives of organizations. This is known as IT governance and is ranked as one of the firms' top concerns. Not surprisingly, it is crucial for organizations to find the affecting factors on IT governance and solve the problems associated with it. Culture in national, organizational or group level is an affecting factor in organizations that can play a role in IT governance and this role is rarely explored in academic research. This paper provides a literature review investigating the influence of culture on IT governance. The research purpose is to identify how culture and IT governance in the companies can be linked together and promote this area for future research. The literature review is done systematically and the findings are classified by using an IT governance framework with three main components of structures, processes and relational mechanisms. The results indicate there is an influence from national and organizational culture on IT governance. However, the number of studies is very few and there is still a lack of knowledge on how culture can influence IT governance. This research calls upon a further research on culture impact on achieving an effective IT governance implementation in organizations.

  • 59.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Han, Shengnan
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Culture Influence on IT Governance: What We Have Learned?2018In: Technology Adoption and Social Issues: Concepts, Methodologies, Tools, and Applications, IGI Global, 2018, no 2018, p. 139-156Chapter in book (Other academic)
    Abstract [en]

    Managers face enormous challenges today to plan the decision rights and responsibilities in order to reach desired IT behaviors which are aligned with business objectives of organizations. This is known as IT governance and is ranked as one of the firms' top concerns. Not surprisingly, it is crucial for organizations to find the affecting factors on IT governance and solve the problems associated with it. Culture in national, organizational or group level is an affecting factor in organizations that can play a role in IT governance and this role is rarely explored in academic research. This paper provides a literature review investigating the influence of culture on IT governance. The research purpose is to identify how culture and IT governance in the companies can be linked together and promote this area for future research. The literature review is done systematically and the findings are classified by using an IT governance framework with three main components of structures, processes and relational mechanisms. The results indicate there is an influence from national and organizational culture on IT governance. However, the number of studies is very few and there is still a lack of knowledge on how culture can influence IT governance. This research calls upon a further research on culture impact on achieving an effective IT governance implementation in organizations.

  • 60.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Han, Shengnan
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    The Influence of Culture on IT Governance: A Literature Review2014In: 2014 47th Hawaii International Conference on System Sciences (HICSS) / [ed] Sprague, R. H., IEEE Computer Society, 2014, p. 4436-4445Conference paper (Refereed)
    Abstract [en]

    IT governance is crucial for managers to regulate the decision rights and responsibilities that the desired IT behaviors and business objectives are aligned with each other. Additionally, culture in national, organizational or group level can play a role in IT governance and this role is rarely explored in academic research. This paper provides a literature review investigating the impact of culture on IT governance. It is aimed to find the linkage between these two concepts and to promote this area for future research. The literature review was done systematically and the findings are categorized by using an IT governance framework which includes three main components: structures, processes and relational mechanisms. The results indicate there is an influence from national and organizational culture on IT governance, especially on relational mechanisms. However, the number of studies is very few and there is still a lack of knowledge on how culture can influence IT governance.

  • 61.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Han, Shengnan
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    The Influence of Organizational Culture on IT Governance Performance: Case of The IT Department in a Large Swedish Company2016In: Proceedings of the 49th Annual Hawaii International Conference on System Sciences / [ed] Tung X. Bui, Ralph H. Sprague, Jr., IEEE Computer Society, 2016Conference paper (Refereed)
    Abstract [en]

    IT governance is one of the top concerns of organizations today seeking to gain value from their IT investments and create competitive advantage. Organizational culture on the other hand is one of the various factors influencing IT governance performance. However there is not much research conducted to understand this topic deeply. This research thus, is exploring the influence of organizational culture on four IT governance performance outcomes through a case study in IT department of a large Swedish company. The results provide evidence that organizational culture is influencing IT governance performance. Specifically the current clan culture orientation of the IT department has led to a successful IT governance performance in cost-effective use of IT. Furthermore adhocracy as the preferred culture is identified to influence IT governance in effective use of IT for growth which is not so successful with the current clan culture.

  • 62.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Han, Shengnan
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    The Role of Culture in IT Governance2014In: Americas Conference on Information Systems (AMCIS 2014): AMCIS 2014, Proceedings, AIS eLibrary , 2014Conference paper (Refereed)
  • 63.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Leidner, Dorothy
    IT Organizational Structure Relationship with IT Governance Performance: Case of a Public Organization2017In: Information Technology Governance in Public Organizations: Theory and Practice / [ed] Lazar Rusu, Gianluigi Viscusi, Cham, Switzerland: Springer, 2017, no 0, p. 229-252Chapter in book (Refereed)
    Abstract [en]

    Information Technology (IT) is widely used in organizations and managers continue to struggle with how to govern IT. IT governance concerns the decision rights and division of responsibilities to achieve value from IT investments. Any IT governance approach is incorporated into a given organizational structure. However in the particular context of public organizations, there is little research on IT organizational structure relationship with IT governance performance. In this research, a case study is done in a public organization to find out how suitable is the organizational structure of the IT department is in relation with the IT governance performance. The results reveal that the IT department organizational structure needs to suit the IT governance performance desired outcomes. In this case, operating as a public organization has actuated the organization to focus on IT governance outcome of effective use of IT for growth. This together with the IT governance archetypes of this public organization for different IT decisions led the IT department leaders to adopt a matrix organizational structure.

  • 64.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Leidner, Dorothy
    Perjons, Erik
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Corrales Estrada, Martha
    How Does the Organizational Culture of Collaborative Networks Influence IT Governance Performance in a Large Organization?2018In: Hawaii International Conference on Systems Sciences 2018 (HICSS-51), 2018, p. 4941-4951Conference paper (Refereed)
    Abstract [en]

    In today's complex organizations, IT governance is an important managerial challenge. IT governance deals with decisions and responsibilities concerning IT. There are many factors influencing IT governance. One factor that has remained relatively unexplored by academic research is that of organizational culture. This research explores the influence of the organizational culture of collaborative networks on IT governance performance. A case study was conducted in a large complex company with several networks. The findings indicated that the networks desire different organizational culture types based on their priorities for IT governance outcomes. A clan organizational culture is desired when aiming for effective use of IT for asset utilization and cost effective use of IT. An adhocracy culture is desired when prioritizing the effective use of IT for business growth. Finally a combination of market and hierarchy organizational culture is desired when seeking effective use of IT for business flexibility and cost cutting.

  • 65.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Leidner, Dorothy
    Perjons, Erik
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Corrales Estrada, Martha
    What is the role of organizational culture in IT governance performance of collaborative virtual networks?2018In: International Journal of IT - Business Alignment and Governance, ISSN 1947-9611, E-ISSN 1947-962X, Vol. 9, no 1, article id 2Article in journal (Refereed)
    Abstract [en]

    In today's complex organizations, IT governance is an important managerial challenge. IT governance deals with decisions and responsibilities concerning IT. There are many factors influencing IT governance. One factor that has remained relatively unexplored by academic research is that of organizational culture. This research explores the influence of the organizational culture of collaborative networks on IT governance performance. A case study was conducted in a large complex company with several networks. The findings indicated that the networks fit better with different organizational culture types based on their priorities for IT governance outcomes to maximize performance. A clan organizational culture is desired when aiming for effective use of IT for asset utilization and cost-effective use of IT. An adhocracy culture fits better when prioritizing the effective use of IT for business growth. Finally, a combination of market and hierarchy organizational culture is desired and fits better when seeking effective use of IT for business flexibility and cost cutting.

  • 66.
    Aasi, Parisa
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Rusu, Lazar
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Vieru, Dragos
    The Role of Culture in IT Governance Five Focus Areas: A Literature Review2017In: International Journal of IT - Business Alignment and Governance, ISSN 1947-9611, E-ISSN 1947-962X, Vol. 8, no 2, article id 3Article, review/survey (Refereed)
    Abstract [en]

    Information technology governance (ITG) is one of the top challenges of managers today and culture in different level can have an important role while implementing IT governance. This is a new and significant issue, which has not been investigated deeply. This paper sets out to provide a systematic review of the literature, focusing on the role of culture in IT governance. The literature review findings are categorized through the lens of IT governance's five focus areas which are IT strategic alignment, IT value delivery, Risk management, IT resource management and Performance measurement. This study contributes to the field of IT governance by reviewing and discussing the existing literature on the role of culture on IT governance. This literature review resulted that there are few research studies in this topic and many of the IT governance focus areas are not covered regarding the role of culture in these IT governance areas.

  • 67.
    Abathun, Addisalem
    Stockholm University, Faculty of Science, Department of Mathematics.
    Asymptotic distribution of zeros of a certain class of hypergeometric polynomials2014Licentiate thesis, monograph (Other academic)
    Abstract [en]

    The thesis consists of two papers, both treating hypergeometric polynomials, and a short introduction. The main results are as follows.In the first paper,we study the asymptotic zero distribution of a family of hypergeometric polynomials in one complex variable as their degree goes to infinity,using the associated differential equations that hypergeometric polynomials satisfy.   We describe in particular the curve complex on which the zeros cluster, as level curves associated to integrals on an algebraic curve derived from the equation.   The new result is first of all that we are able to formulate results on the location of zeros of generalized hypergeometric polynomials in greater generality than before (earlier results are mainly concerned with the Gauss hypergeometric case.) Secondly, we are able to formulate a precise conjucture giving the asymptotic behaviour of zeros in the generalized case of our polynomials, which covers previous results.In the second paper we partly prove one of the  conjectures in the first paper by using Euler integral representation of the Gauss hypergeometric functions together with the Saddle point method.

  • 68.
    Abathun, Addisalem
    et al.
    Stockholm University, Faculty of Science, Department of Mathematics. Addis Ababa University, Ethiopia.
    Bøgvad, Rikard
    Stockholm University, Faculty of Science, Department of Mathematics.
    Asymptotic Distribution of Zeros of a Certain Class of Hypergeometric Polynomialsd2016In: Computational methods in Function Theory, ISSN 1617-9447, E-ISSN 2195-3724, Vol. 16, no 2, p. 167-185Article in journal (Refereed)
    Abstract [en]

    We study the asymptotic behavior of the zeros of a family of a certain class of hypergeometric polynomials [GRAPHICS] , using the associated hypergeometric differential equation, as the parameters go to infinity. The curve configuration on which the zeros cluster is characterized as level curves associated with integrals on an algebraic curve. The algebraic curve is the hypergeometrc differential equation, using a similar approach to the method used in Borcea et al. (Publ Res Inst Math Sci 45(2):525-568, 2009). In a specific degenerate case, we make a conjecture that generalizes work in Boggs and Duren (Comput Methods Funct Theory 1(1):275-287, 2001), Driver and Duren (Algorithms 21(1-4):147-156, 1999), and Duren and Guillou (J Approx Theory 111(2):329-343, 2001), and present experimental evidence to substantiate it.

  • 69.
    Abathun, Addisalem
    et al.
    Stockholm University, Faculty of Science, Department of Mathematics. Addis Ababa University, Ethiopia.
    Bøgvad, Rikard
    Stockholm University, Faculty of Science, Department of Mathematics.
    ZEROS OF A CERTAIN CLASS OF GAUSS HYPERGEOMETRIC POLYNOMIALS2018In: Czechoslovak Mathematical Journal, ISSN 0011-4642, E-ISSN 1572-9141, Vol. 68, no 4, p. 1021-1031Article in journal (Refereed)
    Abstract [en]

    We prove that as n -> infinity, the zeros of the polynomial F-2(1) 9-n, (an + 2) (an + 1) ; z] cluster on (a part of) a level curve of an explicit harmonic function. This generalizes previous results of Boggs, Driver, Duren et al. (1999-2001) to the case of a complex parameter alpha and partially proves a conjecture made by the authors in an earlier work.

  • 70. Abazov, V. M.
    et al.
    Abbott, B.
    Abolins, M.
    Åsman, Barbro
    Stockholm University, Faculty of Science, Department of Physics.
    Search for Events with Leptonic Jets and Missing Transverse Energy in p(p)over-bar Collisions at root s=1.96 TeV2010In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 105, no 21, p. 211802-Article in journal (Refereed)
    Abstract [en]

    We present the first search for pair production of isolated jets of charged leptons in association with a large imbalance in transverse energy in pp̅ collisions using 5.8  fb-1 of integrated luminosity collected by the D0 detector at the Fermilab Tevatron Collider. No excess is observed above the standard model background, and the result is used to set upper limits on the production cross section of pairs of supersymmetric chargino and neutralino particles as a function of “dark-photon” mass, where the dark photon is produced in the decay of the lightest supersymmetric particle

  • 71. Abazov, V. M.
    et al.
    Abbott, B.
    Abolins, M.
    Åsman, Barbro
    Stockholm University, Faculty of Science, Department of Physics.
    Search for Sneutrino Production in e mu Final States in 5.3 fb(-1) of p(p)over-bar Collisions at root s = 1.96 TeV2010In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 105, no 19, p. 191802-Article in journal (Refereed)
    Abstract [en]

    We report the results of a search for R parity violating (RPV) interactions leading to the production of supersymmetric sneutrinos decaying into eμ final states using 5.3  fb-1 of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron Collider. Having observed no evidence for production of eμ resonances, we set direct bounds on the RPV couplings λ311 and λ312 as a function of sneutrino mass.

  • 72.
    Abbas, Haider
    et al.
    KTH, School of ICT, Electronic Systems.
    Magnusson, Christer
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Yngström, Louise
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Hemani, Ahmed
    ICT/Materialfysik.
    Addressing Dynamic Issues in Information Security Management2011In: Information Management & Computer Security, ISSN 0968-5227, E-ISSN 1758-5805, Vol. 19, no 1, p. 5-24Article in journal (Refereed)
    Abstract [en]

    The paper addresses three main problems resulting from uncertainty in information security management: i)dynamically changing security requirements of an organization ii) externalities caused by a security system and iii)obsolete evaluation of security concerns. A framework based on options reasoning borrowed from corporate finance is proposed and adapted to evaluation of security architecture and decision-making for handling these issues at organizational level. The adaptation as methodology is demonstrated by a large case study validating its efficacy.

  • 73. Abbas, Haider
    et al.
    Magnusson, Christer
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Yngström, Louise
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Hemani, Ahmed
    Architectural Description of an Automated System for Uncertainty Issues Management in Information Security2010In: International Journal of computer Science and Information Security, ISSN 1947-5500, Vol. 8, no 3, p. 59-67Article in journal (Refereed)
    Abstract [en]

    Information technology evolves at a faster pace giving organizations a limited scope to comprehend and effectively react to steady flux nature of its progress. Consequently the rapid technological progression raises various concerns for the IT system of an organization i.e. existing hardware/software obsoleteness, uncertain system behavior, interoperability of various components/method, sudden changes in IT security requirements and expiration of security evaluations. These issues are continuous and critical in their nature that create uncertainty in IT infrastructure and threaten the IT security measures of an organization. In this research, Options theory is devised to address uncertainty issues in IT security management and the concepts have been developed/validated through real cases on SHS (Spridnings-och-Hämtningssystem) and ESAM (E-society) systems. AUMSIS (Automated Uncertainty Management System in Information Security) is the ultimate objective of this research which provides an automated system for uncertainty management in information security. The paper presents the architectural description of AUMSIS, its various components, information flow, storage and information processing details using options valuation techniques. It also presents heterogeneous information retrieval problems and their solution. The architecture is validated with examples from SHS system

  • 74. Abbas, Haider
    et al.
    Orlandi, Eugenio
    Aslam Khan, Farrukh
    Popov, Oliver
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Masood, Asif
    Security, Safety and Trust Management2017In: 2017 IEEE 26th International Conference on Enabling Technologies: Infrastructure for Collaborative Enterprises: Proceedings / [ed] Sumitra Reddy, Wojciech Cellary, Mariagrazia Fugini, IEEE Computer Society, 2017, p. 242-243Conference paper (Refereed)
    Abstract [en]

    The continuously evolving nature of today's internet outdates the existing security and safety mechanisms and therefore there is an emerging need to propose robust, powerful and reliable solutions. These advancements have a great impact on the software and system architectures, resulting in a highly dynamic smart networked environment. The systems used within these complex environments have at least two things in common, namely, the need to restrict or grant access for the required resources based on security policy to face security threats, and the need to sustain resilience of the environment in face of safety hazards. Both aspects should consider trust.

  • 75. Abbas, Haider
    et al.
    Yngström, Louise
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Hemani, Ahmed
    Adaptability Infrastructure for Bridging IT Security Evaluation and Options theory2009In: SIN'09, October 6-10, 2009, North Cyprus, Turkey, 2009Conference paper (Refereed)
  • 76. Abbas, Haider
    et al.
    Yngström, Louise
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Hemani, Ahmed
    Empowering Security Evaluation of IT Products with Option Theory2009In: 30th IEEE Symposium on Security and Privacy, Oakland, California, USA, 2009Conference paper (Refereed)
  • 77. Abbas, Haider
    et al.
    Yngström, Louise
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Hemani, Ahmed
    Option Based evaluation: Security Evaluation of IT Products Based on Options Theory2009In: IEEE ECBS-EERC, Novi Sad Serbia, 2009Conference paper (Refereed)
  • 78. Abbas, Haider
    et al.
    Yngström, Louise
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Hemani, Ahmed
    ROA Based Agile Security Evaluation of IT Products for Developing Countries2009Conference paper (Other academic)
  • 79. Abbas, Haider
    et al.
    Yngström, Louise
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences. Säkerhetsinformatik.
    Hemani, Ahmed
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences. Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences. Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences. Mikroelektronik och tillämpad fysik. Tillämpad IT. Tillämpad IT med entreprenörskap.
    Security Evaluation of Products: Bridging the Gap between Common Criteria (CC) and Real Option Thinking2008In: WCECS, 2008Conference paper (Other academic)
  • 80. Abbas, Sk Jahir
    et al.
    Ramacharyulu, P. V. R. K.
    Lo, Hsin-Hsi
    Ali, Sk Imran
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Ke, Shyue-Chu
    A catalytic approach to synthesis of PLP analogs and other environmental protocols in a single handed CaO/TiO2 green nanoparticle2017In: Applied Catalysis B: Environmental, ISSN 0926-3373, E-ISSN 1873-3883, Vol. 210, p. 276-289Article in journal (Refereed)
    Abstract [en]

    As our precursory stage we have focus straight forward on clean catalytic approach for the production of C3 substituted pyridoxal-5 '-phosphate analogues of vitamin B6, and other environmental protocols like photocatalytic activity, green fossil fuels and c-c coupling using efficient biocompatible eggshell related unrivalled materials which show versatility of the catalytic effect on different inorganic support. The eggshell immobilized nanoparticles have encouraging relevance in creation of new molecules and can advantageously be studied by various spectroscopic, thermal and elemental analyses like powder X-ray diffraction (XRD), Raman spectroscopy, UV-vis, Scanning electron microscopy (SEM), Energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area analysis. The elucidate nature of nanoparticles offer: more active site acts as lewis acid, vacancies on the catalyst surface and good to better yield of C3 substituted deoxy and 2-nor deoxy coenzyme pyridoxine (PN), coupling products propargylamines (PA), photo degrading enhancement of MB and nucleophilic substituted fatty acid (BD). This enzyme cofactor explore molecular synthons to synthetic equivalent: 3-deoxy and 2-nor-3-deoxy pyridoxal (PL), pyridoxal oxime (P0), pyridoxamine (PM) and mono phosphate derivative of 3-deoxyPM, 3-deoxyPL respectively and chemistry of selective oxidation and schiff base mechanism was studied and complemented through combined experimental and theoretical molecular orbital calculation consequently. The heterogeneous catalyst has strong selective ability towards selective reducing pyridine diester, bioactive intermediates substances and holds vast potential towards separation for the photogenerated electron-hole pairs and renewable, nontoxic, biodegradable green fossil fuels. The catalyst including environmental concern is reapplicable and strong impressive that can unfold the space of worthy metal component widely and facilitate the scope to take a vital role in different fileds like catalysis, biochemistry, nanoscience, energy and materials science.

  • 81. Abbasi, A.
    et al.
    Damian Risberg, Emilana
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Mink, Janos
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Persson, I.
    Sandström, Magnus
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Sidorov, Y. V.
    Skripkin, Michail
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Ullström, A-S
    Crystallographic and Vibrational Spectroscopic Studies of Octakis(DMSO)lanthanoid(III) Iodides2007In: Inorganic Chemistry, Vol. 46, p. 7731-7741Article in journal (Refereed)
  • 82. Abbasi, A
    et al.
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Beheshti, S
    Kianmehr, E
    Dimethyl 2-chloro-3-tosylmaleate2007In: Acta Crystallographica Section E, Vol. E63, p. o3774-Article in journal (Refereed)
  • 83. Abbasi, A
    et al.
    Golchoubian, H
    Khaniani, Y
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Badiei, A
    N,N'-Bis(2,6-dichlorobenzyl)ethylenediimine2007In: Acta Crystallographica Section E, Vol. E63, p. o3773-Article in journal (Refereed)
  • 84. Abbasi, A.
    et al.
    Habibian, M.
    Sandström, Magnus
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    mer-Trichloridotris(dimethyl sulfide-kS)-rhodium(III)2007In: Acta Crystallographica, Vol. E63, p. m1904-Article in journal (Refereed)
  • 85.
    Abbasi, Abdul
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Muftic, Sead
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    CryptoNET: integrated secure workstation2009In: International Journal of Advanced Science and Technology, ISSN 2005-4238, Vol. 12Article in journal (Refereed)
    Abstract [en]

    In most of the current applications security is usually provided individually. This means that various applications use their own security mechanisms and services, applied only to their own resources and functions. Furthermore, procedures to configure security parameters are usually inconvenient and complicated for non-technical users. As an alternative to this approach, we have designed and implemented Secure Workstation, which represents an integrated security environment and protects local IT resources, messages and operations across multiple applications. It comprises five components, i.e. four most commonly used PC applications: Secure Station Manager (equivalent to Windows Explorer), Secure E-Mail Client, Secure Documents System, and Secure Browser. These four components for their security extensions use functions and credentials of the fifth component, Generic Security Provider [5]. With this approach, we provide standard security services (authentication, confidentiality, and integrity and access control) and also additional, extended security services, such as transparent handling of certificates, use of smart cards, strong authentication protocol, SAML based single-singe-on, secure sessions, and other security functions, to all PC applications with the same set of security modules and parameters.

  • 86.
    Abbasi, Abdul
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Muftic, Sead
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Gernot, Schmölzer
    A Model and Design of a Security Provider for Java Applications2009In: International Conference on Risks and Security of Internet and Systems, Toulouse, France: Yves Deswarte , 2009, Vol. 1, no 4Conference paper (Refereed)
  • 87.
    Abbasi, Abdul
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Muftic, Sead
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Gernot, Schmölzer
    CryptoNET: Design and Implementation of the Secure Email System2009In: International Workshop on Security and Communication Networks, Trondheim, Norway: Svein Johan Knapskog , 2009, Vol. 1, no 1Conference paper (Refereed)
  • 88.
    Abbasi, Abdul
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Muftic, Sead
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Gernot, Schmölzer
    CryptoNET: Secure Federation Protocol and Authorization Policies for SMI2009In: International Conference on Risks and Security of Internet and Systems, Toulouse, France: Yves Deswarte , 2009, Vol. 1, no 4Conference paper (Refereed)
  • 89.
    Abbasi, Alireza
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Structural and Spectroscopic Studies of Solvated Metal Ions2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Crystallographic and spectroscopic studies have been performed of structures, coordination and chemical bonding for series of trivalent metal ions solvated by two oxygen-coordinating solvents, water and dimethyl sulfoxide (DMSO). The hydrated scandium(III) and lanthanoid(III) ions, La to Lu, are surrounded by tricapped trigonal prisms of aqua ligands in the isomorphous series of trifluoromethanesulfonates, [M(H2O)n](CF3SO3)3. For the smallest ions, M = Er, Tm, Yb, Lu, Sc, the hydration numbers decrease, n = 8.96(5), 8.8(1), 8.7(1), 8.5(1), 8.0(1), respectively, with decreasing size of the ion. The crystal structures at ambient temperature indicate randomly distributed vacancies of the capping oxygen atoms, and 2H solid-state NMR of the diamagnetic [M(H2O)n](CF3SO3)3, M = Sc, Lu, Y and La compounds revealed increasing mobility of the water ligands in the coordination sphere with increasing temperature, also for the fully nonahydrated LaIII and YIII ions. The stretching force constants of the Ln-O bonds, evaluated from vibrational spectroscopy, increased from 0.81 to 1.16 N cm-1 for the Ln-6O trigonal prism in a smooth correlation with the bond distances from La to Lu. For the capping Ln-3O bonds the increase from 0.49 to 0.65 N cm-1 reflects the increased ligand-ligand repulsion with decreasing ion size. This is also the reason for the water deficiency of the Er, Tm, Yb, Lu and Sc salts, and for [Sc(H2O)8.0](CF3SO3)3 the repulsion induced a phase transition at about 185 K that, by low temperature crystallography, was found to distort the coordination of water molecules toward a monocapped trigonal prism around the scandium(III) ion.

    All crystal structures of the octakis(dimethyl sulfoxide)lanthanoid(III) iodides comprise discrete [Ln(dmso)8]3+ complexes surrounded by iodide ions. The lanthanum(III) and praseodymium(III) compounds crystallize in the orthorhombic space group Pbca with more efficient packing than for the heavier and smaller ions in the lanthanoid series, which crystallize in the monoclinic space group P21/n. The group 13 metal ions, aluminium(III), gallium(III), indium(III), thallium(III), and also scandium(III) of group 3, form crystalline hexakis(dimethyl sulfoxide) solvates in the space group R 3, with octahedral MO6 coordination entities, which are increasingly compressed along one threefold axis for increasing ionic size. EXAFS measurements on the solvated ions display similar M-O bond distances in dimethyl sulfoxide solution as in the solid solvates. For all the solid dimethyl sulfoxide solvates the strength and nature of the metal-oxygen bond has been evaluated by normal coordinate analysis of vibrational spectra, and correlated with the S-O stretching vibrational mode.

    Distortions from regular octahedral six coordination are discussed for the hydrated isoelectronic soft mercury(II) and thallium(III) ions in the solid bisaquamercury(II) and trisaquatallium(III) trifluoromethanesulfonates, in terms of pseudo Jahn-Teller effects (PJTE). Mercury(II), generally more strongly influenced by PJTE distortions, displays a 2 + 4 Hg-O coordination forming chains that are held together in sheets by hydrogen bonds and in layers by van der Waals interactions, which explain the fragile structure of the crystals.

  • 90. Abbasi, Alireza
    et al.
    Adib, Mehdi
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Dimethyl 3-(tert-butylamino)-5-oxo-7-phenyl-1H,5H-pyrazolo[1,2-a]pyrazole-1,2-dicarboxylate2007In: Acta Crystallographica Section E, Vol. E63, p. o2115–o2116-Article in journal (Refereed)
  • 91. Abbasi, Alireza
    et al.
    Badiei, Alireza
    Khaniani, Yeganeh
    Golchoubian, Hamid
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Inorganic and Structural Chemistry.
    N,N '-bis(2,6-dichlorobenzyl)ethylene-diimine2007In: Acta Crystallographica Section E: Structure Reports Online, ISSN 1600-5368, E-ISSN 1600-5368, Vol. 63, p. o3773-U2712Article in journal (Refereed)
    Abstract [en]

    In the centrosymmetric title compound, C16H12Cl4N2, the asymmetric unit is one half-molecule. Weak van der Waals interactions between the molecules are effective in the molecular packing. This is the first reported structure of a chloro-substituted benzaldehyde derivative that can potentially form a tetradentate ligand.

  • 92. Abbasi, Alireza
    et al.
    Damian Risberg, Emiliana
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Inorganic and Structural Chemistry.
    Mink, Janos
    Persson, Ingmar
    Sandström, Magnus
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Inorganic and Structural Chemistry.
    Sidorov, Yurii V.
    Skripkin, Mikhail Yu.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Inorganic and Structural Chemistry.
    Ullström, Ann-Sofi
    Crystallographic and Vibrational Spectroscopic Studies of Octakis(dimethyl sulfoxide)lanthanoid(III) Iodides2007In: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 46, no 19, p. 7731-7741Article in journal (Refereed)
    Abstract [en]

    The octakis(DMSO) (DMSO = dimethylsulfoxide) neodymium(III), samarium(III), gadolinium(III), dysprosium(III), erbium(III), and lutetium(III) iodides crystallize in the monoclinic space group P21/n (No. 14) with Z = 4, while the octakis(DMSO) iodides of the larger lanthanum(III), cerium(III), and praseodymium(III) ions crystallize in the orthorhombic space group Pbca (No. 61), Z = 8. In all [Ln(OS(Me2)8]I3 compounds the lanthanoid(III) ions coordinate eight DMSO oxygen atoms in a distorted square antiprism. Up to three of the DMSO ligands were found to be disordered and were described by two alternative configurations related by a twist around the metal−oxygen (Ln−O) bond. To resolve the atomic positions and achieve reliable Ln−O bond distances, complete semirigid DMSO molecules with restrained geometry and partial occupancy were refined for the alternative sites. This disorder model was also applied on previously collected data for the monoclinic octakis(DMSO)yttrium(III) iodide. At ambient temperature, the eight Ln−O bond distances are distributed over a range of about 0.1 Å. The average value increases from Ln−O 2.30, 2.34, 2.34, 2.36, 2.38, 2.40 to 2.43 Å (Ln = Lu, Er, Y, Dy, Gd, Sm, and Nd) for the monoclinic [Ln(OSMe2)8]I3 structures, and from 2.44, 2.47 to 2.49 Å (Ln = Pr, Ce, and La) for the orthorhombic structures, respectively. The average of the La−O and Nd−O bond distances remained unchanged at 100 K, 2.49 and 2.43 Å, respectively. Despite longer bond distances and larger Ln−O−S angles, the cell volumes are smaller for the orthorhombic structures (Ln = Pr, Ce, and La) than for the monoclinic structure with Ln = Nd, showing a more efficient packing arrangement. Raman and IR absorption spectra for the [Ln(OS(CH3)2)8]I3 (Ln = La, Ce, Pr, Nd, Gd, Tb, Dy, Er, Lu, and Y) compounds, also deuterated for La and Y, have been recorded and analyzed by means of normal coordinate methods. The force constants for the Ln−O and S−O stretching modes in the complexes increase with decreasing Ln−O bond distance and show increasing polarization of the bonds for the smaller and heavier lanthanoid(III) ions.

  • 93. Abbasi, Alireza
    et al.
    Geranmayeh, Shokoofeh
    Skripkin, Mikhail Y.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Potassium ion-mediated non-covalent bonded coordination polymers2012In: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 41, no 3, p. 850-859Article in journal (Refereed)
    Abstract [en]

    Crystal structures and vibrational spectra of three related network-forming coordination complexes have been studied. Two novel thermodynamically stable pseudo-polymorphic solvated rhodium chloro compounds, [cis-RhCl4(DMSO-kappa S)(2)K](n), 1, and [cis-RhCl4(DMSO-kappa S)(2)K center dot 3H(2)O](n), 2, and one metastable compound [trans-RhCl4(DMSO-kappa S)(2)K center dot 0.25H(2)O](n), 3, crystallize at ambient temperature in the orthorhombic space group P2(1)2(1)2(1) for 1, and the monoclinic space groups P2(1)/n and P2(1)/c for 2 and 3, respectively. All three structures contain [RhCl4(DMSO-kappa S)(2)]-complexes in which the rhodium(III) ions bind to two dimethyl sulfoxide (DMSO) sulfur atoms and four chloride ions in distorted octahedral coordination geometries. The complexes are connected in networks via potassium ions interacting with the Cl- and the DMSO oxygen atoms. As the sum of Shannon ionic radii of K+ and Cl- exceeds the K-Cl distances in compounds under study, these compounds can be described as Rh-Cl-K coordination polymers with non-covalent bonding, which is not common in these systems, forming 1- and 2-D networks for 1/2 and 3, respectively. The 2-D network with nano-layered sheets for compound 3 was also confirmed by TEM images. Further evaluation of the bonding in the cis- and trans-[RhCl4(DMSO-kappa S)(2)](-) entities was obtained by recording Raman and FT-IR absorption spectra and assigning the vibrational frequencies with the support of force-field calculations. The force field study of complexes reveals the strong domination of trans-effect (DMSO-kappa S > Cl) over the effect of non-covalent bonding in coordination polymeric structures. The comparison of calculated RhCl, RhS and SO stretching force constants showed evidence of K+-ligand interactions whereas direct experimental evidences of K+-Cl- interaction were not obtained because of strong overlap of the corresponding spectral region with that where lattice modes and Rh-ligand bendings appear.

  • 94.
    Abbasi, Alireza
    et al.
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Lindqvist-Reis, Patric
    Eriksson, Lars
    Sandström, Dick
    Lidin, Sven
    Persson, Ingmar
    Sandström, Magnus
    Highly hydrated cations: Deficiency, mobility and coordination of water in crystalline nonahydrated scandium(III), yttrium(III) and lanthanoid(III) trifluoromethanesulfonate2005In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 11, no 14, p. 4065-4077Article in journal (Refereed)
    Abstract [en]

    Trivalent lanthanide-like metal ions coordinate nine water oxygen atoms, which form a tricapped trigonal prism in a large number of crystalline hydrates. Water deficiency, randomly distributed over the capping positions, was found for the smallest metal ions in the isomorphous nonahydrated trifluoromethanesulfonates, [M(H2O)(n)]CF3SO3)(3), in which M=Sc-III, Lu-III, Yb-III, Tm-III or Er-III. The hydration number n increases (n=8.0(1), 8.4(1), 8.7(1), 8.8(1) and 8.96(5), respectively) with increasing ionic size. Deuterium (H-2) solid-state NMR spectroscopy revealed fast positional exchange between the coordinated capping and prism water molecules; this exchange started at temperatures higher than about 280 K for lutetium(m) and below 268 K for scandium(m). Similar positional exchange for the fully nonahydrated yttrium(m) and lanthanum(m) compounds started at higher temperatures, over about 330 and 360 K, respectively. An exchange mechanism is proposed that can exchange equatorial and capping water molecules within the restrictions of the crystal lattice, even for fully hydrated lanthanoid(III) ions. Phase transitions occurred for all the water-deficient compounds at; 185 K. The hydrated scandium(III) trifluoromethanesulfonate transforms reversibly (Delta H degrees= -0.80(1) kJ mol(-1) on cooling) to a trigonal unit cell that is almost nine times larger, with the scandium ion surrounded by seven fully occupied and two partly occupied oxygen atom positions in a distorted capped trigonal prism. The hydrogen bonding to the trifluoromethanesulfonate anions stabilises the trigonal prism of water ligands, even for the crowded hydration sphere of the smallest metal ions in the series. Implications for the Lewis acid catalytic activity of the hydrated scandium(III) and lanthanoid(III) trifluoromethanesulfonates for organic syntheses performed in aqueous media are discussed.

  • 95.
    Abbasi, Alireza
    et al.
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Skripkin, Mikhail
    Damian, Emiliana
    Mink, Janos
    Ullström, Ann-Sofi
    Persson, Ingmar
    Sidorov, Yurii
    Sandström, Magnus
    Crystallographic, vibratioal spectroscopic and force field studies of octakis(dimethyl sulfoxide)lanthanide(III) solvatesManuscript (Other academic)
  • 96. Abbasi, Alireza
    et al.
    Skripkin, Mikhail Yu.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Torapava, Natallia
    Ambidentate coordination of dimethyl sulfoxide in rhodium(III) complexes2011In: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 40, no 5, p. 1111-1118Article in journal (Refereed)
    Abstract [en]

    The two dimethyl sulfoxide solvated rhodium(III) compounds, [Rh(dmso-kappa O)(5)(dmso-kappa S)](CF(3)SO(3))(3) (1 & 1* at 298 K and 100 K, respectively) and [Rh(dmso-kappa O)(3)(dmso-kappa S)(2)Cl](CF(3)SO(3))(2) (2), crystallize with orthorhombic unit cells in the space group Pna2(1) (No. 33), Z = 4. In the [Rh(dmso)(6)](3+) complex with slightly distorted octahedral coordination geometry, the Rh-O bond distance is significantly longer with O trans to S, 2.143(6) angstrom (1) and 2.100(6) angstrom (1*), than the mean Rh-O bond distance with O trans to O, 2.019 angstrom (1) and 2.043 angstrom (1*). In the [RhCl(dmso)(5)](3+) complex, the mean Rh-O bond distance with O trans to S, 2.083 angstrom, is slightly longer than that for O trans to Cl, 2.067(4) angstrom, which is consistent with the trans influence DMSO-kappa S > Cl > DMSO-kappa O of the opposite ligands. Raman and IR absorption spectra were recorded and analyzed and a complete assignment of the vibrational bands was achieved with support by force field calculations. An increase in the Rh-O stretching vibrational frequency corresponded to a decreasing trans-influence from the opposite ligand. The Rh-O force constants obtained were correlated with the Rh-O bond lengths, also including previously obtained values for other M(dmso)(6)(3+) complexes with trivalent metal ions. An almost linear correlation was obtained for the MO stretching force constants vs. the reciprocal square of the MO bond lengths. The results show that the metal ion-oxygen bonding of dimethyl sulfoxide ligands is electrostatically dominated in those complexes and that the stretching force constants provide a useful measure of the relative trans-influence of the opposite ligands in hexa-coordinated Rh(III)-complexes.

  • 97. Abbasi, Saeed
    et al.
    Jansson, Anders
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Olander, Lars
    Olofsson, Ulf
    Sellgren, Ulf
    A pin-on-disc study of the rate of airborne wear particle emissions from railway braking materials2012In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 284, p. 18-29Article in journal (Refereed)
    Abstract [en]

    The current study investigates the characteristics of particles generated from the wear of braking materials, and provides an applicable index for measuring and comparing wear particle emissions. A pin-on-disc tribometer equipped with particle measurement instruments was used. The number concentration, size, morphology, and mass concentration of generated particles were investigated and reported for particles 10 nm-32 mu m in diameter. The particles were also collected on filters and investigated using EDS and SEM. The effects of wear mechanisms on particle morphology and changes in particle concentration are discussed. A new index, the airborne wear particle emission rate (AWPER), is suggested that could be used in legislation to control non-exhaust emissions from transport modes, particularly rail transport.

  • 98.
    Abbasi, Saeed
    et al.
    KTH Royal Inst Technol, Dept Machine Design, Stockholm, Sweden.
    Jansson, Anders
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Sellgren, Ulf
    KTH Royal Inst Technol, Dept Machine Design, Stockholm, Sweden.
    Olofsson, Ulf
    KTH Royal Inst Technol, Dept Machine Design, Stockholm, Sweden.
    Particle Emissions From Rail Traffic: A Literature Review2013In: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537, Vol. 43, no 23, p. 2511-2544Article, review/survey (Refereed)
    Abstract [en]

    Particle emissions are a drawback of rail transport. This work is a comprehensive presentation of recent research into particle emissions from rail vehicles. Both exhaust and nonexhaust particle emissions are considered when examining particle characteristics such as PM10, and PM2.5 concentration levels, size, morphology, composition, and adverse health effects, current legislation, and available and proposed solutions for reducing such emissions. High concentration levels in enclosed rail traffic environments are reported and some toxic effects of the particles. The authors find that only a few limited studies have examined the adverse health effects of nonexhaust particle emissions and that no relevant legislation exists. Thus further research in this area is warranted.

  • 99. Abbasi, Saeed
    et al.
    Olander, Lars
    Larsson, Christina
    Olofsson, Ulf
    Jansson, Anders
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Sellgren, Ulf
    A field test study of airborne wear particles from a running regional train2012In: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 226, no 1, p. 95-109Article in journal (Refereed)
    Abstract [en]

    Inhalable airborne particles have inverse health effects. In railways, mechanical brakes, the wheel–rail contact, current collectors, ballast, sleepers, and masonry structures yield particulate matter. Field tests examined a Swedish track using a train instrumented with particle measurement devices, brake pad temperature sensors, and speed and brake sensors. The main objective of this field test was to study the characteristics of particles generated from disc brakes on a running train with an on-board measuring set-up. Two airborne particle sampling points were designated, one near a pad–rotor disc brake contact and a second under the frame, not near a mechanical brake or the wheel–rail contact; the numbers and size distributions of the particles detected were registered and evaluated under various conditions (e.g. activating/deactivating electrical brakes or negotiating curves). During braking, three speed/temperature-dependent particle peaks were identified in the fine region, representing particles 280, 350, and 600 nm in diameter. In the coarse region, a peak was discerned for particles 3–6 µm in diameter. Effects of brake pad temperature on particle size distribution were also investigated. Results indicate that the 280 nm peak increased with increasing temperature, and that electrical braking significantly reduced airborne particle numbers. Field emission scanning electron microscope images captured particles sizing down to 50 nm. The inductively coupled plasma mass spectrometry results indicated that Fe, Cu, Zn, Al, Ca, and Mg were the main elements constituting the particles.

  • 100.
    Abbasian, Saeid
    et al.
    Mittuniversitetet.
    Yazdanfar, Darush
    Mittuniversitetet.
    Hedberg, Charlotta
    Stockholm University, Faculty of Social Sciences, Department of Human Geography.
    The determinant of external financing at the start-up stage: Empirical evidences from Swedish data2014In: World Review of Entrepreneurship, Management and Sustainable Development, ISSN 1746-0573, E-ISSN 1746-0581, Vol. 10, no 1, p. 124-141Article in journal (Refereed)
    Abstract [en]

    Small firms in general have limited access to funding, which is a major problem for entrepreneurs. In particular, this problem is evident for women and ethnic minority groups. The purpose of the study is to examine empirically the impact of gender, ethnicity and other relevant variables on the access to external financing of new small firms. A sample of 2,764 female– and male–owned small businesses, based on a unique and large database gathered through interviews, was investigated employing binary logistic regression models. The results suggest that both gender and ethnicity are significant explanatory variables influencing the access to external capital at the start–up stage. Entrepreneurs' age, experience of starting businesses and education, as well as additional jobs beside their own business, are other variables that influence the way in which entrepreneurs finance their business. Moreover, firm characteristics in terms of personal start–up capital, firm size and legal form have an impact on financing behaviour at start–up. Since the knowledge about this issue is limited, the results of this study add to our understanding of the variables affecting the behaviour of small business endeavours in seeking funding at start–up

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