647 research outputs found

    Growth rates of amenable groups

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    Let Fm be a free group with m generators and let R be a normal subgroup such that Fm /R projects onto ℤ. We give a lower bound for the growth rate of the group Fm / R′(where R′ is the derived subgroup of R) in terms of the length ρ= ρ(R) of the shortest non-trivial relation in R. It follows that the growth rate of Fm / R′ approaches 2m-1 as ρ approaches infinity. This implies that the growth rate of an m-generated amenable group can be arbitrarily close to the maximum value 2m- 1. This answers an open question of P. de la Harpe. We prove that such groups can be found in the class of abelian-by-nilpotent groups as well as in the class of virtually metabelian group

    Possible predictors of depressive syndrome in patients with chronic obstructive pulmonary disease.

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    Recently, the problem of depressive syndrome in COPD patients often attracts the attention of doctors and scientists. It is important to study the relationship between the presence of the depressive syndrome, on the one hand, and the clinical and functional characteristics of COPD patients on the other, in order to determine the categories of patients inclined to develop a depressive syndrome. The purpose of the study: to determine the relationship between the presence of depressive syndrome in COPD patients with the severity of their clinical symptoms of COPD and the level of functional impairments. 52 COPD patients of clinical groups C and D were examined. Depending on the presence of depressive syndrome patients were divided into two subgroups: a subgroup 1 – 15 COPD patients with concomitant depressive syndrome, a subgroup 2 – 37 people without it. The examination included general clinical and functional methods. It was determined that the development of depressive syndrome in COPD patients can be affected by the high severity of clinical symptoms of COPD in general, decreased tolerance to physical activity, long duration of the disease, poor quality of life. At the same time, the levels of functional indicators, in particular, OFV1 and SpO2, may not have a significant relationship with the occurrence of depressive syndrome, even in patients with severe COPD

    Reframing e-assessment: building professional nursing and academic attributes in a first year nursing course

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    This paper documents the relationships between pedagogy and e-assessment in two nursing courses offered at the University of Southern Queensland, Australia. The courses are designed to build the academic, numeracy and technological attributes student nurses need if they are to succeed at university and in the nursing profession. The paper first outlines the management systems supporting the two courses and how they intersect with the e-learning and e-assessment components of course design. These pedagogical choices are then reviewed. While there are lessons to be learnt and improvements to be made, preliminary results suggest students and staff are extremely supportive of the courses. The e-assessment is very positively received with students reporting increased confidence and competency in numeracy, as well as IT, academic, research and communication skills

    Elementary amenable subgroups of R. Thompson's group F

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    The subgroup structure of Thompson's group F is not yet fully understood. The group F is a subgroup of the group PL(I) of orientation preserving, piecewise linear self homeomorphisms of the unit interval and this larger group thus also has a poorly understood subgroup structure. It is reasonable to guess that F is the "only" subgroup of PL(I) that is not elementary amenable. In this paper, we explore the complexity of the elementary amenable subgroups of F in an attempt to understand the boundary between the elementary amenable subgroups and the non-elementary amenable. We construct an example of an elementary amenable subgroup up to class (height) omega squared, where omega is the first infinite ordinal.Comment: 20 page

    Interfering Doorway States and Giant Resonances. I: Resonance Spectrum and Multipole Strengths

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    A phenomenological schematic model of multipole giant resonances (GR) is considered which treats the external interaction via common decay channels on the same footing as the coherent part of the internal residual interaction. The damping due to the coupling to the sea of complicated states is neglected. As a result, the formation of GR is governed by the interplay and competition of two kinds of collectivity, the internal and the external one. The mixing of the doorway components of a GR due to the external interaction influences significantly their multipole strengths, widths and positions in energy. In particular, a narrow resonance state with an appreciable multipole strength is formed when the doorway components strongly overlap.Comment: 20 pages, LaTeX, 3 ps-figures, to appear in PRC (July 1997

    Post-Disaster Housing Reconstruction in Sri Lanka: What Methodology?

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    Research methodology is the procedural framework within which the research is conducted. This includes the overall approach to a problem that could be put into practice in a research process, from the theoretical underpinning to the collection and analysis of data. Choice of methodology depends on the primary drivers: topic to be researched and the specific research questions. Hence, methodological perspectives of managing stakeholder expectations of PDHR context are composed of research philosophies, research strategy, research design, and research techniques. This research belonged to social constructivism or interpretivism within a philosophical continuum. The nature of the study was more toward subjectivism where human behavior favored voluntary stance. Ontological, methodological, epistemological, and axiological positioning carried the characteristics of idealism, ideographic, anti-positivism, and value laden, respectively. Data collection comprises two phases, preliminary and secondary. Exploratory interviews with construction experts in the United Kingdom and Sri Lanka were carried out to refine the interview questions and identify the case studies. Case study interviews during the secondary phase took place in Sri Lanka. Data collected at the preliminary stage were used to assess the attributes of power, legitimacy/proximity, and urgency of stakeholders to the project using Stakeholder Circle™ software. Moreover, the data collected at secondary phase via case studies will be analyzed with NVivo 8. This article aims to discuss these methodological underpinnings in detail applied in a post-disaster housing reconstruction context in Sri Lanka

    On micro-structural effects in dielectric mixtures

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    The paper presents numerical simulations performed on dielectric properties of two-dimensional binary composites on eleven regular space filling tessellations. First, significant contributions of different parameters, which play an important role in the electrical properties of the composite, are introduced both for designing and analyzing material mixtures. Later, influence of structural differences and intrinsic electrical properties of constituents on the composite's over all electrical properties are investigated. The structural differences are resolved by the spectral density representation approach. The numerical technique, without any {\em a-priori} assumptions, for extracting the spectral density function is also presented.Comment: 24 pages, 8 figure and 7 tables. It is submitted to IEEE Transactions on Dielectrics and Electrical Insulatio

    Wanting to become PE teachers in Spain: connections between previous experiences and particular beliefs about school Physical Education and the development of professional teacher identities

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    Physical Education (PE) teachers have previous experiences that both shape their particular beliefs about the role and purpose of this school subject as well as their pedagogical practice. The present study aims to examine and deepen our knowledge of future Spanish PE teachers’ previous experiences of and beliefs about PE that condition their pedagogical practice and intentionality within this school subject. The data reported on in this paper were generated through questionnaires, life-history stories and semi-structured interviews with 24 initial teacher education students in the second year of a degree specialising in PE at a Spanish university. The data was analysed using content and narrative (thematic) analysis. The students, far from being tabula rasa, in their responses show how their previous socialisation period, their subjectivities and identities constitute particular beliefs about PE teaching. More specifically, the results reveal four key themes in the student teachers’ experiences and beliefs that represent four different factors influencing future PE teacher identities: (1) ‘Sport’; (2) ‘PE for health’; (3) ‘A focus on pedagogy’; and (4) ‘A critical orientation’. In conclusion, the study reaffirms the need for further reflection on how previous experiences and beliefs influence the development of professional teacher identities as part of initial teacher education in PE

    The political process of constructing a sustainable London Olympics sports development legacy

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    This study attempts to develop a research agenda for understanding the process of constructing a sustainable Olympic sports development legacy. The research uses a social constructivist perspective to examine the link between the 2012 London Olympic Games and sustainable sports development. The first part of the paper provides justification for the study of sport policy processes using a constructivist lens. This is followed by a section which critically unpacks sustainable sports development drawing on Mosse’s (1998) ideas of process-oriented research and Searle’s conceptualisation of the construction of social reality. Searle’s (1995) concepts of the assignment of function, collective intentionality, collective rules, and human capacity to cope with the environment are considered in relation to the events and discourses emerging from the legacy vision(s) associated with the 2012 London Olympic Games. The paper concludes by proposing a framework for engaging in process oriented research and highlights key elements, research questions, and methodological issues. The proposed constructivist approach can be used to inform policy, practice, and research on sustainable Olympic sports development legacy
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