The introduction of the virtual work environment has resulted in the creation of a new work structure where interaction between employees and leaders occurs through technological innovations such as teleconferencing, emails, and text messages. The absence of physical workspace has also created a diverse work environment with people from various cultural backgrounds working together as virtual teams. Existing studies have been conducted on leadership styles and culture in the traditional work environment, but few empirical studies have been conducted on leadership styles and culture in the virtual work environment. The purpose of this quantitative, nonexperimental survey study was to identify the relationship between cultural backgrounds and leadership styles in the virtual work environment. The data were collected by an online survey using the Bass and Avolio multifactor leadership questionnaire and Hofstede's cultural value survey module from a random sample of 303 participants with leadership roles in virtual work environments. Pearson correlation analysis was used to test the relationship between the dependent variables, transactional and transformational leadership styles, with the independent variables, being power distance, uncertainty avoidance, individualism, and masculinity. The results of the study showed a negative correlation between the transformational and transactional leadership styles for individualism and uncertainty avoidance. There were no correlations between femininity and power distance for the transformational and transactional leadership styles. The study contributes to social change by confirming that cultural backgrounds can impact the effectiveness of the transactional and transformational leadership styles, regardless of the work environment.

Decades of data document that permanent placements of children in the welfare system has been a concern in Mississippi. As foster care rates increase, more children are awaiting placement. Researchers have linked child welfare workers' educational background to placement outcomes for foster care children; however, researchers have not addressed the relationship between child welfare workers' educational backgrounds and foster care placement outcomes in Mississippi. This quantitative study examined the educational backgrounds of social work and nonsocial work child welfare caseworkers and other factors such as children's gender and race as predictors in placement outcomes for children in welfare custody. Attachment theory was used to explain parent-child relationships and the importance of permanent, safe, and nurturing homes for children in the child welfare system. Secondary data were used from the 2017 archival records for 176 child welfare caseworkers' caseloads in the Mississippi Department of Child Protective Services (MDCPS). A simple linear and multiple regression analysis was used to examine child welfare caseworkers' educational background and children's gender and race as predictors for the length of stay in placement outcomes. The results revealed that caseworkers' educational backgrounds were not a significant predictor of placement outcomes but gender and race combined were significant in predicting the length of stay in placement outcomes for children in custody. Results from this study could promote positive social change within MDCPS by providing data to inform agency policy and procedures for child welfare practice, which could then result in more timely placements of reunification or adoption for children in the welfare system who are currently spending 36 months or more in traditional foster care.

The overall agenda for the research reported here grew out of semi-structured interviews with senior educational managers from a tertiary educational institution in Taiwan. These managers raised a number of issues, including the changing profile of tertiary students, the changing nature of English curricula, the increasing need for English teaching staff to be adaptable, highly qualified and research-active, and the growing pressure on institutions to introduce English language proficiency benchmarking. Each of these issues can be related to the impact of globalization and, in particular, the impact of the globalization of English, on the education sector. Following a critical review of selected literature on the impact of globalization on the teaching and learning of English, each of these issues, as it affects the tertiary education sector in Taiwan, was explored. Analysis of the Taiwanese national curriculum guidelines for schools, strongly influenced by academics in the tertiary education sector, revealed a number of problems relating to a lack of proficiency benchmarking and a lack of coherence, consistency and transparency in some areas. These problems may be associated with the initial phase of transition from a grammar-based curriculum to a more communicatively-oriented, outcomes-centered one. Problems of a similar type were indicated in responses to questions relating to curriculum matters included in a questionnaire distributed to a sample of teachers of English in the tertiary sector. Among other things revealed by questionnaire responses was the fact that many survey participants had received no training in English teaching. The results of a C-test (one that was initially used in a major European study) taken by a sample of entry-level and exit-level Bachelors degree students indicated a wide variation in proficiency, with individual scores differing by as much as 64 percentage points in the case of exit-level students. Furthermore, there was a difference of almost 10 percentage points between the mean scores of students from two different institutions who had majored in English. These results indicate some of the difficulties that Taiwan faces in attempting to establish graduation proficiency benchmarking. -ii- C-test participants completed a background questionnaire, the responses indicating a generally positive attitude towards English-speaking people, a general willingness to use English in situations where there was the option of not doing so, and a strong tendency towards instrumental motivation. Although one of the factors that appeared to have a positive impact on C-test performance was time spent in an English-speaking country, fewer than 18% of respondents had done so. Although there appears to be considerable anxiety and uncertainty associated with the teaching of English at tertiary level in Taiwan, and some genuine cause for concern, there are also many positive indicators of future success. Teachers and educational managers are aware of the problems they currently face and appear determined to resolve them. Taiwanese academics are increasingly involved in language-related research and increasingly prepared to interrogate their own practices, and Taiwan, unlike some other countries in Asia, is moving towards graduation proficiency benchmarking.

<p>This thesis deals with different aspects of string and /p/-brane theories. One of the motivations for string theory is to unify the forces in nature and produce a quantum theory of gravity. /p/-branes and related objects arise in string theory and are related to a non-perturbative definition of the theory. The results of this thesis might help in understanding string theory better. The first part of the thesis introduces and discusses relevant topics for the second part of the thesis which consists of five papers.</p><p>In the three first papers we develop and treat a perturbative approach to relativistic /p/-branes around stretched geometries. The unperturbed theory is described by a string- or particle-like theory. The theory is solved, within perturbation theory, by constructing successive canonical transformations which map the theory to the unperturbed one order by order. The result is used to define a quantum theory which requires for consistency d = 25 + p dimensions for the bosonic /p/-branes and d = 11 for the supermembrane. This is one of the first quantum results for extended objects beyond string theory and is a confirmation of the expectation of an eleven-dimensional quantum membrane.</p><p>The two last papers deal with a gauged WZNW-approach to strings moving on non-trivial space-times. The groups used in the formulation of these models are connected to Hermitian symmetric spaces of non-compact type. We have found that the GKO-construction does not yield a unitary spectrum. We will show that there exists, however, a different approach, the BRST approach, which gives unitarity under certain conditions. This is the first example of a difference between the GKO- and BRST construction. This is one of the first proofs of unitarity of a string theory in a non-trivial non-compact space-time. Furthermore, new critical string theories in dimensions less then 26 or 10 is found for the bosonic and supersymmetric string, respectively.</p>

<p>In this thesis, two aspects of string theory are discussed, tensionless strings and supersymmetric sigma models.</p><p>The equivalent to a massless particle in string theory is a tensionless string. Even almost 30 years after it was first mentioned, it is still quite poorly understood. We discuss how tensionless strings give rise to exact solutions to supergravity and solve closed tensionless string theory in the ten dimensional maximally supersymmetric plane wave background, a contraction of AdS(5)xS(5) where tensionless strings are of great interest due to their proposed relation to higher spin gauge theory via the AdS/CFT correspondence.</p><p>For a sigma model, the amount of supersymmetry on its worldsheet restricts the geometry of the target space. For N=(2,2) supersymmetry, for example, the target space has to be bi-hermitian. Recently, with generalized complex geometry, a new mathematical framework was developed that is especially suited to discuss the target space geometry of sigma models in a Hamiltonian formulation. Bi-hermitian geometry is so-called generalized Kähler geometry but the relation is involved. We discuss various amounts of supersymmetry in phase space and show that this relation can be established by considering the equivalence between the Hamilton and Lagrange formulation of the sigma model. In the study of generalized supersymmetric sigma models, we find objects that favor a geometrical interpretation beyond generalized complex geometry.</p>

<p>This thesis considers two different aspects of string theory, the tensionless limit of the string and supersymmetric sigma models with extended supersymmetry. First, the tensionless limit is used to find a IIB supergravity background generated by a tensionless string. The background has the characteristics of a gravitational shock-wave. Then, the quantization of the tensionless string in a pp-wave background is performed and the result is found to agree with what is obtained by taking a tensionless limit directly in the quantized theory of the tensile string. Hence, in the pp-wave background the tensionless limit commutes with quantization. Next, supersymmetric sigma models and the relation between extended world-sheet supersymmetry and target space geometry is studied. The sigma model with N=(2,2) extended supersymmetry is considered and the requirement on the target space to have a bi-Hermitean geometry is reviewed. The Hamiltonian formulation of the model is constructed and the target space is shown to have generalized Kähler geometry. The equivalence between bi-Hermitean geometry and generalized Kähler follows, in this context, from the equivalence between the Lagrangian- and Hamiltonian formulation of the sigma model. Then, T-duality in the Hamiltonian formulation of the sigma model is studied and the explicit T-duality transformation is constructed. It is shown that the transformation is a symplectomorphism, i.e. a generalization of a canonical transformation. Under certain assumptions, the amount of extended supersymmetry present in the sigma model is shown to be preserved under the T-duality transformation. Next, extended supersymmetry in a first order formulation of the sigma model is studied. By requiring N=(2,2) extended world-sheet supersymmetry an intriguing geometrical structure arises and in a special case generalized complex geometry is found to be contained in the new framework.</p>

In this thesis, two aspects of string theory are discussed, tensionless strings and supersymmetric sigma models. The equivalent to a massless particle in string theory is a tensionless string. Even almost 30 years after it was first mentioned, it is still quite poorly understood. We discuss how tensionless strings give rise to exact solutions to supergravity and solve closed tensionless string theory in the ten dimensional maximally supersymmetric plane wave background, a contraction of AdS(5)xS(5) where tensionless strings are of great interest due to their proposed relation to higher spin gauge theory via the AdS/CFT correspondence. For a sigma model, the amount of supersymmetry on its worldsheet restricts the geometry of the target space. For N=(2,2) supersymmetry, for example, the target space has to be bi-hermitian. Recently, with generalized complex geometry, a new mathematical framework was developed that is especially suited to discuss the target space geometry of sigma models in a Hamiltonian formulation. Bi-hermitian geometry is so-called generalized Kähler geometry but the relation is involved. We discuss various amounts of supersymmetry in phase space and show that this relation can be established by considering the equivalence between the Hamilton and Lagrange formulation of the sigma model. In the study of generalized supersymmetric sigma models, we find objects that favor a geometrical interpretation beyond generalized complex geometry.

This dissertation examines how young people with Kurdish backgrounds form their identity in Sweden with regards to processes of inclusion and exclusion. It also sheds light on the ways these young people deal with ethnic discrimination and racism. Further, the study outlines the importance of these social processes for the discipline of social work and the ways social workers can work with disadvantaged and marginalized groups and endorse their struggle for social justice and full equal citizenship beyond racist and discriminatory practices. The empirical analysis is built on interviews with 28 young men and women with Kurdish backgrounds in Sweden. Postcolonial theory, belonging and identity formation constitute the central conceptual framework of this study. The young people referred to different sites in which they experienced ethnic discrimination and stigmatization. These experiences involved the labor market, mass media, housing segregation, legal system and school system. The interviewees also referred to the roles of ‘ordinary’ Swedes in obstructing their participation in the Swedish society through exclusionary discourses relating to Swedish identity. The interviewees’ life situation in Sweden, sense of ethnic discrimination as well as disputes over identity making with other young people with Middle-Eastern background are among the most important reasons for fostering strong Kurdish nationalist sentiments, issues that are related to the ways they can exercise their citizenship rights in Sweden and how they deal with exclusionary practices in their everyday life. The study shows that the interviewees respond to and resist ethnic discrimination in a variety of ways including interpersonal debates and discussions, changing their names to Swedish names, strengthening differences between the self and the other, violence, silence and deliberately ignoring racism. They also challenged and spoke out against the gendered racism that they were subjected to in their daily lives due to the paternalist discourse of ”honor-killing”. The research participants had been denied an equal place within the boundary of Swedishness partly due to a racist postcolonial discourse that valued whiteness highly. Paradoxically, some interviewees reproduced the same discourse through choosing to use it against black people, Africans, newly-arrived Kurdish immigrants (”imports”), ”Gypsies” and Islam in order to claim a modern Kurdish identity as near to whiteness as possible. This indicates the multiple dimensions of racism. Those who are subjected to racism and ethnic discrimination can be discriminatory and reproduce the racist discourse. Despite unequal power relations, both dominant and minoritized subjects are all marked by the postcolonial condition in structuring subjectivities, belonging and identification.

University of Macau / Faculty of Education

This thesis considers two different aspects of string theory, the tensionless limit of the string and supersymmetric sigma models with extended supersymmetry. First, the tensionless limit is used to find a IIB supergravity background generated by a tensionless string. The background has the characteristics of a gravitational shock-wave. Then, the quantization of the tensionless string in a pp-wave background is performed and the result is found to agree with what is obtained by taking a tensionless limit directly in the quantized theory of the tensile string. Hence, in the pp-wave background the tensionless limit commutes with quantization. Next, supersymmetric sigma models and the relation between extended world-sheet supersymmetry and target space geometry is studied. The sigma model with N=(2,2) extended supersymmetry is considered and the requirement on the target space to have a bi-Hermitean geometry is reviewed. The Hamiltonian formulation of the model is constructed and the target space is shown to have generalized Kähler geometry. The equivalence between bi-Hermitean geometry and generalized Kähler follows, in this context, from the equivalence between the Lagrangian- and Hamiltonian formulation of the sigma model. Then, T-duality in the Hamiltonian formulation of the sigma model is studied and the explicit T-duality transformation is constructed. It is shown that the transformation is a symplectomorphism, i.e. a generalization of a canonical transformation. Under certain assumptions, the amount of extended supersymmetry present in the sigma model is shown to be preserved under the T-duality transformation. Next, extended supersymmetry in a first order formulation of the sigma model is studied. By requiring N=(2,2) extended world-sheet supersymmetry an intriguing geometrical structure arises and in a special case generalized complex geometry is found to be contained in the new framework.