923 resultados para Actions of Compact Lie Groups


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Background Poor clinical handover has been associated with inaccurate clinical assessment and diagnosis, delays in diagnosis and test ordering, medication errors and decreased patient satisfaction in the acute care setting. Research on the handover process in the residential aged care sector is very limited. Purpose The aims of this study were to: (i) Develop an in-depth understanding of the handover process in aged care by mapping all the key activities and their information dynamics, (ii) Identify gaps in information exchange in the handover process and analyze implications for resident safety, (iii) Develop practical recommendations on how information communication technology (ICT) can improve the process and resident safety. Methods The study was undertaken at a large metropolitan facility in NSW with more than 300 residents and a staff including 55 registered nurses (RNs) and 146 assistants in nursing (AINs). A total of 3 focus groups, 12 interviews and 3 observation sessions were conducted over a period from July to October 2010. Process mapping was undertaken by translating the qualitative data via a five-category code book that was developed prior to the analysis. Results Three major sub-processes were identified and mapped. The three major stages are Handover process (HOP) I “Information gathering by RN”, HOP II “Preparation of preliminary handover sheet” and HOP III “Execution of handover meeting”. Inefficient processes were identified in relation to the handover including duplication of information, utilization of multiple communication modes and information sources, and lack of standardization. Conclusion By providing a robust process model of handover this study has made two critical contributions to research in aged care: (i) a means to identify important, possibly suboptimal practices; and (ii) valuable evidence to plan and improve ICT implementation in residential aged care. The mapping of this process enabled analysis of gaps in information flow and potential impacts on resident safety. In addition it offers the basis for further studies into a process that, despite its importance for securing resident safety and continuity of care, lacks research.

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We develop a political-economic model of foreign aid allocation. Each ethnic group in the donor country lobbies the government to allocate more aid to its country of origin, and the government accepts political contributions from lobby groups. Initial per-capita income of the recipients and those of the ethnic groups are shown to be important determinants of the solution of the political equilibrium. We also examine the effects of changes in the degree of corruption, aid fatigue, and ethnic composition, in the donor country on the allocation of aid.

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The crucial role of the drug carrier surface chemical moeities on the uptake and in vitro release of drug is discussed here in a systematic manner. Mesoporous alumina with a wide pore size distribution (2-7 nm) functionalized with various hydrophilic and hydrophobic surface chemical groups was employed as the carrier for delivery of the model drug ibuprofen. Surface functionalization with hydrophobic groups resulted in low degree of drug loading (approximately 20%) and fast rate of release (85% over a period of 5 h) whereas hydrophilic groups resulted in a significantly higher drug payloads (21%-45%) and slower rate of release (12%-40% over a period of 5 h). Depending on the chemical moiety, the diffusion controlled (proportional to time(-0.5)) drug release was additionally observed to be dependent on the mode of arrangement of the functional groups on the alumina surface as well as on the pore characteristics of the matrix. For all mesoporous alumina systems the drug dosages were far lower than the maximum recommended therapeutic dosages (MRTD) for oral delivery. We envisage that the present study would aid in the design of delivery systems capable of sustained release of multiple drugs.

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A chemoselective, neutral, and efficient strategy for the reduction of azides to corresponding amines catalyzed by dioxobis(N,N,-diethyldithiocarbamato) molybdenum complex (1, MoO2[S2CNEt2](2)) in the presence of phenylsilane is discovered. This chemoselective reduction strategy tolerates a variety of reducible functional groups.

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Supramolecular ordering of organic semiconductors is the key factor defining their electrical characteristics. Yet, it is extremely difficult to control, particularly at the interface with metal and dielectric surfaces in semiconducting devices. We have explored the growth of n-type semiconducting films based on hydrogen-bonded monoalkylnaphthalenediimide (NDI-R) from solution and through vapor deposition on both conductive and insulating surfaces. We combined scanning tunneling and atomic force microscopies with X-ray diffraction analysis to characterize, at the submolecular level, the evolution of the NDI-R molecular packing in going from monolayers to thin films. On a conducting (graphite) surface, the first monolayer of NDI-R molecules adsorbs in a flat-lying (face-on) geometry, whereas in subsequent layers the molecules pack edge-on in islands (Stranski–Krastanov-like growth). On SiO2, the NDI-R molecules form into islands comprising edge-on packed molecules (Volmer–Weber mode). Under all the explored conditions, self-complementary H bonding of the imide groups dictates the molecular assembly. The measured electron mobility of the resulting films is similar to that of dialkylated NDI molecules without H bonding. The work emphasizes the importance of H bonding interactions for controlling the ordering of organic semiconductors, and demonstrates a connection between on-surface self-assembly and the structural parameters of thin films used in electronic devices.

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Aortic valve stenosis (AS) is an active disease process akin to atherosclerosis, with chronic inflammation, lipid accumulation, extracellular matrix remodeling, fibrosis, and extensive calcification of the valves being characteristic features of the disease. The detailed mechanisms and pathogenesis of AS are still incompletely understood, however, and pharmacological treatments targeted toward components of the disease are not currently available. In this thesis project, my coworkers and I studied stenotic aortic valves obtained from 86 patients undergoing valve replacement for clinically significant AS. Non-stenotic control valves (n=17) were obtained from patients undergoing cardiac transplantation or from organ donors without cardiac disease. We identified a novel inflammatory factor, namely mast cell, in stenotic aortic valves and present evidence showing that this multipotent inflammatory cell may participate in the pathogenesis of AS. Using immunohistochemistry and double immunofluorescence stainings, we found that a considerable number of mast cells accumulate in stenotic valves and, in contrast to normal valves, the mast cells in diseased valves were in an activated state. Moreover, valvular mast cells contained two effective proteases, chymase and cathepsin G, which may participate in adverse remodeling of the valves either by inducing fibrosis (chymase and cathepsin G) or by degrading elastin fibers in the valves (cathepsin G). As chymase and cathepsin G are both capable of generating the profibrotic peptide angiotensin II, we also studied the expression and activity of angiotensin-converting enzyme (ACE) in the valves. Using RT-PCR, imunohistochemistry, and autoradiography, we observed a significant increase in the expression and activity of ACE in stenotic valves. Besides mast cell-derived cathepsin G, aortic valves contained other elastolytic cathepsins (S, K, and V). Using immunohistochemistry, RT-PCR, and fluorometric microassay, we showed that the expression and activity of these cathepsins were augmented in stenotic valves. Furthermore, in stenotic but not in normal valves, we observed a distinctive pattern of elastin fiber degradation and disorganization. Importantly, this characteristic elastin degradation observed in diseased valves could be mimicked by adding exogenous cathepsins to control valves, which initially contained intact elastin fibers. In stenotic leaflets, the collagen/elastin ratio was increased and correlated positively with smoking, a potent AS-accelerating factor. Indeed, cigarette smoke could also directly activate cultured mast cells and fibroblasts. Next, we analyzed the expression and activity of neutral endopeptidase (NEP), which parallels the actions of ACE in degrading bradykinin (BK) and thus inactivates antifibrotic mechanisms in tissues. Real-time RT-PCR and autoradiography revealed NEP expression and activity to be enhanced in stenotic valves compared to controls. Furthermore, both BK receptors (1 and 2) were present in aortic valves and upregulated in stenotic leaflets. Isolated valve myofibroblasts expressed NEP and BK receptors, and their upregulation occurred in response to inflammation. Finally, we observed that the complement system, a source of several proinflammatory mediators and also a potential activator of valvular mast cells, was activated in stenotic valves. Moreover, receptors for the complement-derived effectors C3a and C5a were expressed in aortic valves and in cultured aortic valve myofibroblasts, in which their expression was induced by inflammation as well as by cigarette smoke. In conclusion, our findings revealed several novel mechanisms of inflammation (mast cells and mast cell-derived mediators, complement activation), fibrosis (ACE, chymase, cathepsin G, NEP), and elastin fiber degradation (cathepsins) in stenotic aortic valves and highlighted these effectors as possible pathogenic contributors to AS. These results support the notion of AS as an active process with inflammation and extracellular matrix remodeling as its key features and identify possible new targets for medical therapy in AS.

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The surface chemistry and dispersion properties of aqueous Ti 3AlC2 suspension were studied in terms of hydrolysis, adsorption, electrokinetic, and rheological measurements. The Ti 3AlC2 particle had complex surface hydroxyl groups, such as ≡Ti-OH,=Al-OH, and -OTi-(OH)2, etc. The surface charging of the Ti3AlC2 particle and the ion environment of suspensions were governed by these surface groups, which thus strongly influenced the stability of Ti3AlC2 suspensions. PAA dispersant was added into the Ti3AlC2 suspension to depress the hydrolysis of the surface groups by the adsorption protection mechanism and to increase the stability of the suspension by the steric effect. Ti3AlC2 suspensions with 2.0 dwb% PAA had an excellent stability at pH=∼5 and presented the characteristics of Newtonian fluid. Based on the well-dispersed suspension, dense Ti3AlC2 materials were obtained by slip casting and after pressureless sintering. This work provides a feasible forming method for the engineering applications of MAX-phase ceramics, wherein complex shapes, large dimensions, or controlled microstructures are needed.

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Introduction Patients post sepsis syndromes have a poor quality of life and a high rate of recurring illness or mortality. Follow-up clinics have been instituted for patients postgeneral intensive care but evidence is sparse, and there has been no clinic specifically for survivors of sepsis. The aim of this trial is to investigate if targeted screening and appropriate intervention to these patients can result in an improved quality of life (Short Form 36 health survey (SF36V.2)), decreased mortality in the first 12 months, decreased readmission to hospital and/or decreased use of health resources. Methods and analysis 204 patients postsepsis syndromes will be randomised to one of the two groups. The intervention group will attend an outpatient clinic two monthly for 6 months and receive screening and targeted intervention. The usual care group will remain under the care of their physician. To analyse the results, a baseline comparison will be carried out between each group. Generalised estimating equations will compare the SF36 domain scores between groups and across time points. Mortality will be compared between groups using a Cox proportional hazards (time until death) analysis. Time to first readmission will be compared between groups by a survival analysis. Healthcare costs will be compared between groups using a generalised linear model. Economic (health resource) evaluation will be a within-trial incremental cost utility analysis with a societal perspective. Ethics and dissemination Ethical approval has been granted by the Royal Brisbane and Women’s Hospital Human Research Ethics Committee (HREC; HREC/13/QRBW/17), The University of Queensland HREC (2013000543), Griffith University (RHS/08/14/HREC) and the Australian Government Department of Health (26/2013). The results of this study will be submitted to peer-reviewed intensive care journals and presented at national and international intensive care and/or rehabilitation conferences.

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The gravitational waveform (GWF) generated by inspiralling compact binaries moving in quasi-circular orbits is computed at the third post-Newtonian (3PN) approximation to general relativity. Our motivation is two-fold: (i) to provide accurate templates for the data analysis of gravitational wave inspiral signals in laser interferometric detectors; (ii) to provide the associated spin-weighted spherical harmonic decomposition to facilitate comparison and match of the high post-Newtonian prediction for the inspiral waveform to the numerically-generated waveforms for the merger and ringdown. This extension of the GWF by half a PN order (with respect to previous work at 2.5PN order) is based on the algorithm of the multipolar post-Minkowskian formalism, and mandates the computation of the relations between the radiative, canonical and source multipole moments for general sources at 3PN order. We also obtain the 3PN extension of the source multipole moments in the case of compact binaries, and compute the contributions of hereditary terms (tails, tails-of-tails and memory integrals) up to 3PN order. The end results are given for both the complete plus and cross polarizations and the separate spin-weighted spherical harmonic modes.

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Purpose To examine the effects of optical blur, auditory distractors and age on eye movement patterns while performing a driving hazard perception test (HPT). Methods Twenty young (mean age 27.1 ± 4.6 years) and 20 older (73.3 ± 5.7 years) drivers with normal vision completed a HPT in a repeated-measures counterbalanced design while their eye movements were recorded. Testing was performed under two visual (best-corrected vision and with +2.00DS blur) and two distractor (with and without auditory distraction) conditions. Participants were required to respond to road hazards appearing in the HPT videos of real-world driving scenes and their hazard response times were recorded. Results Blur and distractors each significantly delayed hazard response time, by 0.42 and 0.76s respectively (p<0.05). A significant interaction between age and distractors indicated that older drivers were more affected by distractors than young drivers (response with distractors delayed by 0.96 and 0.60s respectively). There were no other two- or three-way interaction effect on response time. With blur, both groups fixated significantly longer on hazards before responding compared to best-corrected vision. In the presence of distractors, both groups exhibited delayed first fixation on the hazards and spent less time fixating on the hazards. There were also significant differences in eye movement characteristics between groups, where older drivers exhibited smaller saccades, delayed first fixation on hazards, and shorter fixation duration on hazards compared to the young drivers. Conclusions Collectively, the findings of delayed hazard response times and alterations in eye movement patterns with blur and distractors provide further evidence that visual impairment and distractors are independently detrimental to driving safety given that delayed hazard response times are linked to increased crash risk.

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Hard Custom, Hard Dance: Social Organisation, (Un)Differentiation and Notions of Power in a Tabiteuean Community, Southern Kiribati is an ethnographic study of a village community. This work analyses social organisation on the island of Tabiteuea in the Micronesian state of Kiribati, examining the intertwining of hierarchical and egalitarian traits, meanwhile bringing a new perspective to scholarly discussions of social differentiation by introducing the concept of undifferentiation to describe non-hierarchical social forms and practices. Particular attention is paid to local ideas concerning symbolic power, abstractly understood as the potency for social reproduction, but also examined in one of its forms; authority understood as the right to speak. The workings of social differentiation and undifferentiation in the village are specifically studied in two contexts connected by local notions of power: the meetinghouse institution (te maneaba) and traditional dancing (te mwaie). This dissertation is based on 11 months of anthropological fieldwork in 1999‒2000 in Kiribati and Fiji, with an emphasis on participant observation and the collection of oral tradition (narratives and songs). The questions are approached through three distinct but interrelated topics: (i) A key narrative of the community ‒ the story of an ancestor without descendants ‒ is presented and discussed, along with other narratives. (ii) The Kiribati meetinghouse institution, te maneaba, is considered in terms of oral tradition as well as present-day practices and customs. (iii) Kiribati dancing (te mwaie) is examined through a discussion of competing dance groups, followed by an extended case study of four dance events. In the course of this work the community of close to four hundred inhabitants is depicted as constructed primarily of clans and households, but also of churches, work co-operatives and dance groups, but also as a significant and valued social unit in itself, and a part of the wider island district. In these partly cross-cutting and overlapping social matrices, people are alternatingly organised by the distinct values and logic of differentiation and undifferentiation. At different levels of social integration and in different modes of social and discursive practice, there are heightened moments of differentiation, followed by active undifferentiation. The central notions concerning power and authority to emerge are, firstly, that in order to be valued and utilised, power needs to be controlled. Secondly, power is not allowed to centralize in the hands of one person or group for any long period of time. Thirdly, out of the permanent reach of people, power/authority is always, on the one hand, left outside the factual community and, on the other, vested in community, the social whole. Several forms of differentiation and undifferentiation emerge, but these appear to be systematically related. Social differentiation building on typically Austronesian complementary differences (such as male:female, elder:younger, autochtonous:allotochtonous) is valued, even if eventually restricted, whereas differentiation based on non-complementary differences (such as monetary wealth or level of education) is generally resisted, and/or is subsumed by the complementary distinctions. The concomitant forms of undifferentiation are likewise hierarchically organised. On the level of the society as a whole, undifferentiation means circumscribing and ultimately withholding social hierarchy. Potential hierarchy is both based on a combination of valued complementary differences between social groups and individuals, but also limited by virtue of the undoing of these differences; for example, in the dissolution of seniority (elder-younger) and gender (male-female) into sameness. Like the suspension of hierarchy, undifferentiation as transformation requires the recognition of pre-existing difference and does not mean devaluing the difference. This form of undifferentiation is ultimately encompassed by the first one, as the processes of the differentiation, whether transformed or not, are always halted. Finally, undifferentiation can mean the prevention of non-complementary differences between social groups or individuals. This form of undifferentiation, like the differentiation it works on, takes place on a lower level of societal ideology, as both the differences and their prevention are always encompassed by the complementary differences and their undoing. It is concluded that Southern Kiribati society be seen as a combination of a severely limited and decentralised hierarchy (differentiation) and of a tightly conditional and contextual (intra-category) equality (undifferentiation), and that it is distinctly characterised by an enduring tension between these contradicting social forms and cultural notions. With reference to the local notion of hardness used to characterise custom on this particular island as well as dance in general, it is argued in this work that in this Tabiteuean community some forms of differentiation are valued though strictly delimited or even undone, whereas other forms of differentiation are a perceived as a threat to community, necessitating pre-emptive imposition of undifferentiation. Power, though sought after and displayed - particularly in dancing - must always remain controlled.

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Corporate social responsibility (CSR) is no longer only an issue of companies but a concern shared by e.g. the European Union, the International Labour Organization, labour market organizations and many others. This thesis examines what kind of voluntary corporate social responsibility exceeding the minimum level set in the legislation can be expected from the Finnish companies. The research was based on the interviews of some representatives of Finnish companies and of external stakeholders. Earlier Finnish empirical research on the topic has solely analysed the stakeholder thinking and the ethics of the views of the company representatives. The views of the external stakeholders brought ht up a much more versatile perspective on the voluntary corporate social responsibility of the companies. That is the particular surplus value of this research. This research, founded on stakeholder thinking, evaluated what kind of starting points and ideas on responsibility the views of the representatives of the companies and the external stakeholders were based on the voluntary social responsibility. Furthermore, the research also investigated how their views about the corporate social responsibility indicated the benefits achieved on the cooperative actions with different partners - for example companies, communities and public administration. To fulfil the aims of the research, the following questions were used as part tasks in mapping the basic foundations and starting points expressed by the representatives of the companies and the external stakeholders: 1) How do laws, directions concerning social responsibility of companies, and opinions and demands of the stakeholders guide and affect the voluntary corporate social responsibility? 2) How can companies assume voluntary corporate social responsibility in addition to their core functions and without compromising their profitability, and how does, for example, the tightening competition affect the possibility of taking responsibility? 3) What kind of ethic and moral foundations is the corporate social responsibility based on? 4) What kind of roles can companies have in securing and promoting the well-being of citizens in Finland and on the global market as one subsystem of the society? The views on the voluntary corporate social responsibility of nine big companies, one medium-sized company and one small company, all considered responsible pioneer companies, were studied with surveys and half-structured theme interviews between 2003 and 2004. The research proceeded as a theory-bounded study. The empirical material and the previous stakeholder thinking theories (Takala 2000b, Vehkaperä 2003) guided the thesis and worked abductively in interplay with each other during the research process. (Tuomi, Sarajärvi 2002.) The aims and the methods of the research and the themes of the interviews were defined on the basis of that information. The aims of the research were surveyed qualitatively with the strategy of a multiple case study. Representatives from nine big peer companies and nine external stakeholders were interviewed with half-structured themes between 2004 and 2005. The external stakeholders and the peer companies were chosen with the "thinking" of theoretical replication by Yin, according to which the views of the representatives of those groups would differ from those of the pioneer companies and also from those of each others. The multiple case study supports analysing the internal cohesion of the views of different groups and comparing their differences, and it supports theoretical evaluation and theory-building as well. (Yin 2003.) Another reason for choosing the external stakeholders was their known cooperation with companies. The spoken argumentations of the company and stakeholder representatives on the voluntary social responsibility of the companies were analysed and interpreted in the first place with an analytic discourse analysis, and the argumentations were classified allusively into the stakeholder discourses in three of the part tasks. In the discourse analysis, argumentations of the speech is seen to be intervowen with cultural meanings. (Jokinen, Juhila 1999.) The views of the representatives of the pioneer companies and the external stakeholders were more stakeholder-orientated than the views of the representatives of the peer companies. For the most part, the voluntary corporate social responsibility was seemingly targeted on single, small cooperation projects of the companies and external stakeholders. The pioneer companies had more of those projects, and they were participating in the projects more actively than the peer companies were. The significant result in this research was the notion that, in particular, the representatives of the pioneer companies and external stakeholders did not consider employing and paying taxes to be enough of reciprocal corporate social responsibility. However, they still wanted to preserve the Finnish welfare model, and the interviewees did not wish major changes in the present legislation or the social agreements. According to this study, the voluntary corporate social responsibility is motivated by ethical utilitarianism which varied from very narrow to very wide in relation to benefits achieved by companies and stakeholders (Velasquez 2002, Lagerspetz 2004). Compared with the peer companies, more of the representatives of the pioneer companies and of external stakeholders estimated that companies in their decision-making and operations considered not only the advantages and the benefits of the owners and other internal stakeholders, but also those of the external stakeholders and of the whole society. However, all interviewees expressed more or less strongly that the economic responsibility guides the voluntary responsible actions of the companies in the first place. This kind of utilitarian foundation of behaviour appeared from this research was named as business-orientated company moral. This thesis also presents a new voluntary corporate social responsibility model with four variables on the stakeholder discourses and their distinctive characteristics. The utilitarian motivation of a company s behaviour on their operations has been criticized on the grounds that the end justifies the means. It has also been stated that it is impossible to evaluate the benefits of the utilitarian type of actions to the individuals and the society. It is expected however that companies for their part promote the material and immaterial well-being of the individuals on the global, national and local markets. The expectations are so strong that if companies do not take into account the ethical and moral values, they can possibly suffer significant financial losses. All stakeholders, especially consumers, can with their own choices promote the responsible behaviour of the companies. Key words: voluntary corporate social responsibility, external stakeholders, corporate citizenship, ethics and morality, utilitarianism, stakeholder discourses, welfare society, globalisation

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Since the 1990s, European policy strategies have stressed the mutual responsibility and joint action of all societal branches in preventing social problems. Network policy is an integral part of the new governance that generates a new kind of dependency between the state and civil society in formulating and adhering to policy goals. Using empirical group interview data collected in Helsinki, the capital of Finland, this case study explores local multi-agency groups and their efforts to prevent the exclusion of children and young people. These groups consist mainly of professionals from the social office, youth clubs and schools. The study shows that these multi-agency groups serve as forums for professional negotiation where the intervention dilemma of liberal society can be addressed: the question of when it is justified and necessary for an authority or network to intervene in the life of children and their families, and how this is to be done. An element of tension in multi-agency prevention is introduced by the fact that its objectives and means are anchored both in the old tradition of the welfare state and in communitarian rhetoric. Thus multi-agency groups mend deficiencies in wellbeing and normalcy while at the same time try to co-ordinate the creation of the new community, which will hopefully reduce the burden on the public sector. Some of the professionals interviewed were keen to see new and even forceful interventions to guide the youth or to compel parents to assume their responsibilities. In group discussions, this approach often met resistance. The deeper the social problems that the professionals worked with, the more solidarity they showed for the families or the young people in need. Nothing seems to assure professionals and to legitimise their professional position better than advocating the under-privileged against the uncertainties of life and the structural inequalities of society. The groups that grappled with the clear, specific needs of certain children and families were the most capable of co-operation. This requires the approval of different powers and the expertise of distinct professions as well as a forum to negotiate case-specific actions in professional confidentiality. The ideals of primary prevention for everyone and value discussions alone fail to inspire sufficient multiagency co-operation. The ideal of a network seems to give word and shape to those societal goals that are difficult or even impossible to reach, but are nevertheless yearned for: mutual understanding of the good life, close social relationships, mutual trust and active agency for all citizens. Individualisation, the multiplicity of life styles and the possibility to choose have come true in such a way that the very idea of a mutual and binding network can be attained only momentarily and between restricted participants. In conclusion, uniting professional networks that negotiate intervention dilemmas with citizen networks based on changing compassions and feelings of moral superiority seems impossible. Rather, one should encourage openness to scrutiny among tangential or contradicting groups, networks and communities. Key words: network policy, prevention of exclusion, multi-agency groups, young people

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The thesis examines urban issues arising from the transformation from state socialism to a market economy. The main topics are residential differentiation, i.e., uneven spatial distribution of social groups across urban residential areas, and the effects of housing policy and town planning on urban development. The case study is development in Tallinn, the capital city of Estonia, in the context of development of Central and Eastern European cities under and after socialism. The main body of the thesis consists of four separately published refereed articles. The research question that brings the articles together is how the residential (socio-spatial) pattern of cities developed during the state socialist period and how and why that pattern has changed since the transformation to a market economy began. The first article reviews the literature on residential differentiation in Budapest, Prague, Tallinn and Warsaw under state socialism from the viewpoint of the role of housing policy in the processes of residential differentiation at various stages of the socialist era. The paper shows how the socialist housing provision system produced socio-occupational residential differentiation directly and indirectly and it describes how the residential patterns of these cities developed. The second article is critical of oversimplified accounts of rapid reorganisation of the overall socio-spatial pattern of post-socialist cities and of claims that residential mobility has had a straightforward role in it. The Tallinn case study, consisting of an analysis of the distribution of socio-economic groups across eight city districts and over four housing types in 1999 as well as examining the role of residential mobility in differentiation during the 1990s, provides contrasting evidence. The third article analyses the role and effects of housing policies in Tallinn s residential differentiation. The focus is on contemporary post-privatisation housing-policy measures and their effects. The article shows that the Estonian housing policies do not even aim to reduce, prevent or slow down the harmful effects of the considerable income disparities that are manifest in housing inequality and residential differentiation. The fourth article examines the development of Tallinn s urban planning system 1991-2004 from the viewpoint of what means it has provided the city with to intervene in urban development and how the city has used these tools. The paper finds that despite some recent progress in planning, its role in guiding where and how the city actually developed has so far been limited. Tallinn s urban development is rather initiated and driven by private agents seeking profit from their investment in land. The thesis includes original empirical research in the three articles that analyse development since socialism. The second article employs quantitative data and methods, primarily index calculation, whereas the third and the fourth ones draw from a survey of policy documents combined with interviews with key informants. Keywords: residential differentiation, housing policy, urban planning, post-socialist transformation, Estonia, Tallinn

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This thesis comprises four intercomplementary parts that introduce new approaches to brittle reaction layers and mechanical compatibility of metalloceramic joints created when fusing dental ceramics to titanium. Several different methods including atomic layer deposition (ALD), sessile drop contact angle measurements, scanning acoustic microscopy (SAM), three-point bending (TPB, DIN 13 927 / ISO 9693), cross-section microscopy, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) were employed. The first part investigates the effects of TiO2 layer structure and thickness on the joint strength of the titanium-metalloceramic system. Samples with all tested TiO2 thicknesses displayed good ceramics adhesion to Ti, and uniform TPB results. The fracture mode was independent of oxide layer thickness and structure. Cracking occurred deeper inside titanium, in the oxygen-rich Ti[O]x solid solution surface layer. During dental ceramics firing TiO2 layers dissociate and joints become brittle with increased dissolution of oxygen into metallic Ti and consequent reduction in the metal plasticity. To accomplish an ideal metalloceramic joint this needs to be resolved. The second part introduces photoinduced superhydrophilicity of TiO2. Test samples with ALD deposited anatase TiO2 films were produced. Samples were irradiated with UV light to induce superhydrophilicity of the surfaces through a cascade leading to increased amount of surface hydroxyl groups. Superhydrophilicity (contact angle ~0˚) was achieved within 2 minutes of UV radiation. Partial recovery of the contact angle was observed during the first 10 minutes after UV exposure. Total recovery was not observed within 24h storage. Photoinduced ultrahydrophilicity can be used to enhance wettability of titanium surfaces, an important factor in dental ceramics veneering processes. The third part addresses interlayers designed to restrain oxygen dissolution into Ti during dental ceramics fusing. The main requirements for an ideal interlayer material are proposed. Based on these criteria and systematic exclusion of possible interlayer materials silver (Ag) interlayers were chosen. TPB results were significantly better in when 5 μm Ag interlayers were used compared to only Al2O3-blasted samples. In samples with these Ag interlayers multiple cracks occurred inside dental ceramics, none inside Ti structure. Ag interlayers of 5 μm on Al2O3-blasted samples can be efficiently used to retard formation of the brittle oxygen-rich Ti[O]x layer, thus enhancing metalloceramic joint integrity. The most brittle component in metalloceramic joints with 5 μm Ag interlayers was bulk dental ceramics instead of Ti[O]x. The fourth part investigates the importance of mechanical interlocking. According to the results, the significance of mechanical interlocking achieved by conventional surface treatments can be questioned as long as the formation of the brittle layers (mainly oxygen-rich Ti[O]x) cannot be sufficiently controlled. In summary in contrast to former impressions of thick titanium oxide layers this thesis clearly demonstrates diffusion of oxygen from sintering atmosphere and SiO2 to Ti structures during dental ceramics firing and the following formation of brittle Ti[O]x solid solution as the most important factors predisposing joints between Ti and SiO2-based dental ceramics to low strength. This among other predisposing factors such as residual stresses created by the coefficient of thermal expansion mismatch between dental ceramics and Ti frameworks can be avoided with Ag interlayers.