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  • 51.
    Aasa, Jenny
    et al.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Vare, Daniel
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Motwani, Hitesh V.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Jenssen, Dag
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Quantification of the mutagenic potency and repair of glycidol-induced DNA lesions2016In: Mutation research. Genetic toxicology and environmental mutagenesis, ISSN 1383-5718, E-ISSN 1879-3592, Vol. 805, p. 38-45Article in journal (Refereed)
    Abstract [en]

    Glycidol (Gly) is an electrophilic low-molecular weight epoxide that is classified by IARC as probably carcinogenic to humans. Humans might be exposed to Gly from food, e.g. refined vegetable oils, where Gly has been found as a food process contaminant. It is therefore important to investigate and quantify the genotoxicity of Gly as a primary step towards cancer risk assessment of the human exposure. Here, quantification of the mutagenic potency expressed per dose (AUC: area under the concentration time curve) of Gly has been performed in Chinese hamster ovary (CHO) cells, using the HPRT assay. The dose of Gly was estimated in the cell exposure medium by trapping Gly with a strong nucleophile, cob(I)alamin, to form stable cobalamin adducts for analysis by LC-MS/MS. Gly was stable in the exposure medium during the time for cell treatment, and thus the dose in vitro is the initial concentration x cell treatment time. Gly induced mutations in the hprt-gene at ante of 0.08 +/- 0:01 mutations/10(5) cells/mMh. Through comparison with the effect of ionizing radiation in the same system a relative mutagenic potency of 9.5 rad-eq./mMh was obtained, which could be used for comparison of genotoxicity of chemicals and between test systems and also in procedures for quantitative cancer risk assessment. Gly was shown to induce strand breaks, that were repaired by base excision repair. Furthermore, Gly-induced lesions, present during replication, were found to delay the replication fork elongation. From experiments with repair deficient cells, homologous recombination repair and the ERCC1-XPF complex were indicated to be recruited to support in the repair of the damage related to the stalled replication elongation. The type of DNA damage responsible for the mutagenic effect of Gly could not be concluded from the present study.

  • 52.
    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 dose of glycidol in children and estimation of associated cancer riskManuscript (preprint) (Other academic)
    Abstract [en]

    Children are more susceptible to exposures to harmful compounds compared to adults. Monitoring of the actual exposures in vivo is important to enable risk mitigation actions. The general population, including children, is exposed to the carcinogen glycidol through food. A possible exposure source to glycidol is food containing refined cooking oils where it is present as a process-induced contaminant in the form of fatty acid esters.

    In the present study internal (in vivo) doses of the genotoxic and carcinogenic compound glycidol have been determined in a cohort of 50 children and in a reference group of 12 adults (non-smokers and smokers). The lifetime in vivo doses of glycidol have been calculated from the levels of the hemoglobin (Hb) adduct N-(2,3-dihydroxypropyl)-valine in blood samples from the subjects, demonstrating about a 5-fold variation between the children (71–322 µMh). This variation is likely due to different dietary habits and/or different genotypes/phenotypes of the enzymes involved in the detoxification of glycidol. Data from the adults indicate that the non-smoking subjects are exposed to about the same level as the children, whereas the smoking subjects have about double levels, likely due to the presence of glycidol in tobacco smoke. The estimated exposure to glycidol in the children is higher than those estimated by European Food Safety Authority.

    The calculated relative cancer risk increment due to glycidol exposure demonstrated an unacceptable risk for all subjects. The excess lifetime risk based on the estimated lifetime in vivo doses of glycidol exceeded 1/1000, which should be compared to a generally applied acceptable lifetime risk level of 1/100 000. A small contribution to the internal dose of glycidol from other precursors to the measured Hb adduct, and corresponding contribution to estimated risks from intake of glycidol from food cannot though be excluded.

  • 53.
    Aasa, Jenny
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Cancer Risk Assessment of Glycidol: Evaluation of a Multiplicative Risk Model for Genotoxic Compounds2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Humans are exposed to chemical compounds in everyday life, both from the environment and from endogenous processes. Some compounds constitute a risk for cancer development. One such compound is glycidol, which is genotoxic and an animal carcinogen. It is the model compound of this work, partly due to its presence in food. Glycidol, often together with 3-monochloropropane-1,2-diol (3-MCPD), occurs in the form of esters particularly in refined cooking oils, which are used in a variety of food products. The esters are hydrolyzed in the gastrointestinal tract to form glycidol (and 3-MCPD).

    The aim of the thesis has been to evaluate an approach for cancer risk estimation of genotoxic carcinogens based on a multiplicative (relative) risk model and genotoxic potency. Further, the aim was to estimate the cancer risk for exposure to glycidol via food. Measurement of the internal doses (concentration × time) of glycidol in the studied biological systems, including humans, has been crucial. Glycidol is electrophilic and forms adducts with nucleophilic sites in proteins and DNA. The doses of glycidol were quantified by mass spectrometry: in vivo from adduct levels to hemoglobin (Hb); in vitro from adducts to cob(I)alamin.

    The first part of the thesis concerns the genotoxic potency (genotoxic response per internal dose) of glycidol, measured in vitro by mutation studies and in vivo by micronuclei as a biomarker for genotoxicity (short-term studies in mice). The results were compared to that of ionizing radiation, used as a standard, to estimate the relative genotoxic potency of glycidol: 10 and 15 rad-equ./mMh from mutations and micronuclei, respectively. No induction of micronuclei was observed for the related compound 3-MCPD.

    Tumor incidence from published carcinogenicity studies of glycidol in mice and rats, together with the measured in vivo doses, was evaluated with the relative cancer risk model. A good agreement between predicted and observed tumor incidence was shown, and no significant difference of the obtained cancer risk coefficients (risk per dose) between mice (5.1 % per mMh) and rats (5.4 % per mMh) was observed. The overall results support that the relative risk coefficient (β) is independent of sex, tumor site, and species, and indicated that it can be transferred also to humans. The doubling dose, expressed as 1/β, is the dose that is required to double the background tumor incidence. The mean of the doubling doses from mice and rats (19 mMh) was assumed valid for risk estimation for humans. Transfer of β of glycidol to rad-equ. via its relative genotoxic potency showed a risk coefficient in agreement with the relative cancer risk coefficient of ionizing radiation.

    In the final work, the lifetime (70 years) in vivo doses of glycidol were calculated from measured Hb adduct levels in blood from 50 children and 12 adults, and compared to the doubling dose. A fivefold variation was observed in the in vivo doses. The estimated lifetime excess cancer risk from glycidol exceeds 1/1000. This is much higher than what is considered as an acceptable risk.

    To conclude, the multiplicative (relative) risk model together with relative genotoxic potency is promising to use in an approach for cancer risk estimation and in line with 3R (reduce-refine-replace) initiatives.

  • 54.
    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.

  • 55.
    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)
  • 56.
    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)
  • 57.
    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.

  • 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.
    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.

  • 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?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.

  • 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.
    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.

  • 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.
    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.

  • 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 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.

  • 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.
    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.

  • 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.
    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)
  • 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
    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.

  • 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.
    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.

  • 67.
    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.

  • 68.
    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.

  • 69.
    Aatela, Ann
    Stockholm University, Faculty of Social Sciences, Department of Child and Youth Studies.
    Tvillingskap, identitetsutveckling och delad eller gemensam skolgång.: - Resonemang bland föräldrar, lärare och tvillingar2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 70.
    Abarca, David
    Stockholm University, Faculty of Humanities, Department of Asian, Middle Eastern and Turkish Studies, Japanese Studies.
    Förebyggandet av självmord: En komparativ studie mellan Sverige och Japan2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 71.
    Abarca-Pereda, Enrique
    et al.
    Stockholm University, Faculty of Social Sciences, School of Business.
    Hungria Garcia, Rosane
    Stockholm University, Faculty of Social Sciences, School of Business.
    Technology Reshaping Relationships:: The case of FöreningsSparbanken2001Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The financial system is currently undergoing structural changes all over the world. Thanks to the advances of technology, banks are also changing the way they interact with their customers. From a face-to-face to a faceless contact, via cash machines and the Internet, banks are urging to create effective communication channels that maintain close relationships with their customers. To better illustrate this situation, this study was based on the case of FöreningsSparbaken, a Swedish retail bank, which has a traditional structure and is also undergoing structural changes. With the implementation of new technologies, the bank's customers are experimenting some dissatisfaction concerning the new services provided. Little personal contact, reduction in service options and payment of Internet service fees are the major negative aspects that customers are facing with the bank's changes. These issues are addressed and discussed in this research on the basis of marketing approach.

  • 72.
    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.

  • 73.
    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.

  • 74.
    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.

  • 75. 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

  • 76. 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.

  • 77.
    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.

  • 78. 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

  • 79. 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.

  • 80. 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)
  • 81. 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)
  • 82. 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)
  • 83. 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)
  • 84. 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)
  • 85.
    Abbas, Sheimaa
    Stockholm University, Faculty of Social Sciences, Department of Social Work.
    Feminism och mångkulturalism: en fallstudie om motsättningar mellan individrättigheter och grupprättigheter2005Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Hedersrelaterat våld och praktiserandet av traditioner som arrangerade äktenskap och polygami har aktualiserat diskurser rörande erkännande av kulturella divergenser i en rad västliga länder. Studiens syfte är att belysa ståndpunkter i diskursen som rör kvinnors individuella rättigheter och gruppens rättigheter i ett mångkulturellt sammanhang vilket sker ut ett textanalytiskt perspektiv samt ur det levda livets. Jag utgår från filosofen Martha Nussbaum teori om mänskliga funktionsförmågor och definition av mänskliga rättigheter. Jag har analyserat två aktörers texter i diskursen, Susan Moller Okin (förespråkar individrättigheter) samt Charles Taylor (förespråkar grupprättigheter). Studiens centrala fråga samt övergripande frågeställningar är:

    Vad är mänskliga rättigheter?

    - ur det filosofiska perspektivet,

    - ur Taylors respektive Okins ståndpunkter och

    - ur det levda livets?

    Jag har intervjuat en kvinna, från en annan kulturell kontext än den svenska, om hennes valmöjligheter och handlingsutrymme. Jag kom fram till att Okins perspektiv överensstämmer med Nussbaum angående huruvida individens rättigheter skall ges företräde framför gruppens preferenser, vilket de bör enligt min analys, medan Taylor står längre ifrån och i vissa avseenden går helt emot Nussbaums teori.

  • 86. 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.

  • 87. 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)
  • 88. 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)
  • 89. 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)
  • 90. 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)
  • 91.
    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.

  • 92.
    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)
  • 93.
    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)
  • 94.
    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)
  • 95.
    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.

  • 96. 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)
  • 97. 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.

  • 98. 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.

  • 99. 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.

  • 100.
    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.

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