Asteroid 4 Vesta, the largest differentiated body in the asteroid belt, is a protoplanet, much like those that accreted to form the Earth. Understanding the geology of Vesta furthers understanding of early differentiation processes that occurred on Earth and helps define igneous processes occurring on other differentiated bodies in the early solar system. Howardite, eucrite and diogenite (HED) meteorites, which are thought to have originated from Vesta, can be analyzed to better understand the geology of that asteroid. Here my colleagues and I investigate the petrology and geochemistry of two groups of HEDs. This work is timely, in that the insights gained from these studies can be used to interpret data from the Dawn spacecraft, which has just been placed into orbit around Vesta. In the first four parts of this dissertation we investigate the origin of olivine in diogenites, which are ultramafic cumulates from Vesta. We discover that the majority of these samples are dimict (two-component) breccias, composed of harzburgitic and orthopyroxenitic lithologies. This is contrary to the traditional belief that all diogenites are orthopyroxenites with small amounts of cumulus olivine. Using bulk and in situ trace element chemistries, along with mineral major/minor element compositions, we demonstrate that these two lithologies were likely related through fractional crystallization. We also examine an anomalous achondritic dunite, and use geochemistry and petrology to demonstrate that it is the first recognized dunite belonging to the HED group. This sample likely also fractionated from a melt prior to the fractionation of harzburgitic and orthopyroxenitic diogenites. In the final part of this dissertation, we investigate compositional and textural heterogeneity in a large group of paired howardites, Vestan regolith breccias composed of diogenite and eucrite. We find significant compositional and textural variation within the group, and a preferential distribution of eucritic material in the finer grain sizes. This suggests an immature regolith, and has implications for interpretation of spectral data to be collected by the Dawn orbiter at Vesta.

Abstract The evolutions of microstructure and texture in 2205 duplex stainless steel (DSS) welds produced by two high energy density (HED) processes, CO2 laser beam welding (LBW) and electron beam welding (EBW) were investigated. A variety of analytical techniques were applied for the study on microstructure and texture of the welds. In which, optical microscopy and electron microscopy were used to evaluate the detailed microstructure. X-ray diffraction (XRD) was put to investigate the crystallographic textures among the base metal, heat affected zone and fusion zone. Particular attention was focused on the determination of microtexture in HED welds by using electron backscatter diffraction (EBSD) technique. After that, an effort was put to compare the results by both of X-ray macro-texture and EBSD-microtexture. The recorded micrographs illustrates that the HED welds are mainly composed of d-ferrite grained structure, which is further decorated with allotriomorphic and Widmanst&#x00E4;tten austenite (g) at grain boundaries. With preheating treatment, the volume fraction of austenite in LB weld is gradually increased, and then leading to a completely different morphology. An apparent amount of transformation twins are found in g phase under TEM observations. No matter that they are Widmanst&#x00E4;tten austenite in nonpreheated welds or blocky austenite in preheated welds, all of the transformation twins have the same {111} twin boundary. Furthermore, modulated fringes composed of ferrite, secondary austenite and amorphous phase are also found in the nonpreheated LB weld. It is ascribed to the rapid cooling effect occurred in the nonpreheated LB weld. Two chromium nitrides (CrN and Cr2N) are also identified and attributed to their different driving forces. A remarkable texture gradient is found in the base metal along the thickness direction for both of austenite and ferrite phases in 2205 duplex stainless steel. The texture is governed separately by the {001}//ND-fibre, a-fibre, Goss and rotated cube components. Despite the analogous local texture evolutions revealing in both LB and EB welds, the global solidification textures in the two processes are considerably different. For which, the texture of LB weld is predominantly evolved with the Goss component. However, the texture of EB weld is mainly composed of the pronounced cube {001}<100>, while the Goss {011}<100> and rotated cube {001}<110> are weakened. The microtexture analysis shows that the centre region of the weld is dominated by oriented nucleation mechanism. Whereas, regions near the fusion boundaries are governed by oriented growth mechanism. The texture feature from EBSD does consist well with the XRD measured result. Moreover, the measurement of local texture from EB weld clearly indicates that a high percentage of high angle grain boundaries distributed in the crown. By contrary, a high percentage of low angle grain boundaries distributed in the root. Both of them again reflect the cooling effect of weld on the solidification mechanism. Throughout this study, the key factors to be responsible for the evolution of solidification texture of HED welded DSS are summarized. Those are thermal conductivity of the weld, turbulent flow in the molten pool, parent textures and the orientation relationship between ferrite and austenite.

The Howardite-Eucrite-Diogenite (HED) meteorites are a suite of basalts, cumulates and breccias which originate from one differentiated parent body, and are linked to the asteroid Vesta. The HEDs are petrologically diverse with a range of major, minor and trace element compositions. Early crystallisation ages are recorded and so the HEDs provide us with a unique snapshot into the early solar system. The aim of this thesis is to investigate the petrogenesis of the eucrites and diogenites by addressing two questions. What is the Bulk Silicate Vesta (BSV) composition? What differentiation and magmatic processes have occurred? Putative BSV compositions were derived from the geochemistry of the meteorites and geophysical observations of Vesta. Series of one-atmosphere experiments and thermodynamic models investigated the BSV phase relations. Olivine crystallised at ~1625 °C, followed by orthopyroxene at ~1350 °C and feldspar at ~1125 °C. Low-Ca pyroxene-melt partition coefficients for the minor and trace elements were measured. The compatibility of the REEs and HFSEs in low- Ca pyroxene increased by a factor of three, as temperature decreased from 1300-1125 °C and calcium content increased from Wo_0.5-Wo₈. These partition coefficients were combined with the observed phase relations to perform geochemical trace element calculations of differentiation and magmatic processes. My results suggest that BSV had an Mg#(100&ast;(Mg/(Mg+Fe²⁺)) between 75-80, > 43 wt. % SiO₂, 2.5 x CI refractory lithophile elements, 0.5 wt. % MnO and 0.75 wt. % Cr₂O₃. A three stage model for Vesta's evolution is suggested. Firstly, extensive if not global partial melting of BSV. Then, equilibrium crystallisation of the mantle and fractional crystallisation of mantle-derived melts produced diogenitic cumulates and eucrite liquids, accounting for the range in major and trace element abundances. The re-equilibration of trapped melt in cumulates is also thought to have occurred. Finally, crustal anatexis produced the range in trace element fractionations seen.

Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-07-13T18:04:36Z No. of bitstreams: 1 DIS_RAFAEL_RODRIGUES_DE_MELLO_COMPLETO.pdf: 1737900 bytes, checksum: aa27096e6fa75c8c7ba944c805895e75 (MD5) / Made available in DSpace on 2017-07-13T18:04:37Z (GMT). No. of bitstreams: 1 DIS_RAFAEL_RODRIGUES_DE_MELLO_COMPLETO.pdf: 1737900 bytes, checksum: aa27096e6fa75c8c7ba944c805895e75 (MD5) Previous issue date: 2017-03-30 / It?s not unusual to see consumers buying and consuming many products and services with the intention to live through ludic experiences. Nowadays, it?s known how these forms of consumptions can contribute to the consumer?s well-being, either by conceiving episodic pleasures, or by leading to some personal growth. Despite a number of studies exploring how services and products can individually be a source of these experiences, little has been dedicated to comprehending how both a product and a service can be consumed at the same time and space. This restricted scope has limited the knowledge of some ?ornamented consumption?, on which, with the intention of live a richer experience, the consumer deliberately bring a complementary product to be consumed during a service. Willing to comprehend how the consumers can use such products to create symbiotic experiences with a service, and how these consumptions can benefit his or her well-being, the present dissertation explored the ?cosplay experience?. The cosplayers bring and wear their own cosplays at geek conventions, intentionally enriching their experiences inside these spaces by characterizing themselves as some fictional character from the geek culture, widening their range of interactions and activities during the con, such as posing to some photos or playing the character in an improvised scene in front of a crowd of other consumers. Through the observation of geek conventions and a series of videographic interviews with cosplayers, this study assessed how the cosplay can shift the way the consumer interpret the geek convention, becoming seemed as just a stage for the use of cosplays; with the cosplay being used both as a way to intensify the ludic and escapist aspects of the convention experience, and/or a form of self-expression and personal challenge, evoking multiple long term benefits to the consumer well-being, as self-comprehension, social skills and body acceptance. / Consumidores costumam comprar e consumir diversos produtos e servi?os na inten??o de viver experi?ncias l?dicas. Hoje em dia se compreende que tais formas de consumos possuem impactos sobre o bem-estar de uma pessoa, seja por conceder um prazer epis?dico, seja por contribuir para o crescimento pessoal do consumidor. Apesar de diversos estudos explorarem como um servi?o ou um produto em espec?fico podem ser fontes de experi?ncias que contribuem para o bem-estar, pouco se explorou como ambos podem ser consumidos em um mesmo espa?o e tempo. Este escopo restringido limita a compreens?o de consumos ornamentados, onde, com a inten??o de consumir uma experi?ncia mais rica, o consumidor leva um produto complementar para ser consumido durante um servi?o. Visando compreender como o consumidor pode usar estes produtos para criar esta experi?ncia simbi?tica com o servi?o, e como este consumo contribui para o seu bem-estar, a atual disserta??o explorou a experi?ncia cosplay. Os cosplayers levam e vestem os seus pr?prios cosplays nos eventos geek, intencionalmente enriquecendo as suas experi?ncias nestes espa?os ao se caracterizarem e interpretarem algum personagem fict?cio da cultura geek, ampliando o seu leque de intera??es e atividades no evento, como posar para fotos e realizar encena??es improvisadas em frente a uma plateia de outros consumidores. Atrav?s de observa??es participantes em eventos geek e entrevistas videogr?ficas com cosplayers, este estudo averiguou que o uso do cosplay altera a forma como o cosplayer interpreta o evento geek em geral, se tornando somente um palco para o uso do cosplay; com o cosplay podendo ser consumido tanto como uma forma de intensificar as atividades l?dicas e escapistas da experi?ncia no evento, quanto como um meio para express?o e desafio pessoal, gerando diferentes retornos a longo prazo, como autocompreens?o, habilidades sociais e aceita??o corporal.

Made available in DSpace on 2014-12-17T15:55:05Z (GMT). No. of bitstreams: 1 NaraGA_DISSERT.pdf: 1500404 bytes, checksum: 25c744f7a7ac2b02102cad56468c08e6 (MD5) Previous issue date: 2014-02-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Amenities value provided by green areas, sea, river and natural landscapes are hardly perceived and incorporated on urban planning and development. In this work, distance and view to protected and non-protected green areas, sea and river were evaluated as to how they increase the housing prices in Natal. Hedonic pricing methods were used with linear models to estimate the marginal implicit value of environmental, residential and neighborhood features. Results on Chapter 1 demonstrate the view to the sea and protected natural areas were largely capitalized on housing prices, while non-protected natural areas didn t display such effect. Housing prices also increase when close to the sea or to parks entrance. However, housing prices fall when houses are near non-protected natural areas. When estates with sea view were excluded, the protected natural areas view and a longer distance to non-protected natural areas increased dwelling prices. Results on Chapter 2 point the sea view as an hedonic variable the contributes strongly to the property selling prices, even though not always as the greatest contributor; furthermore, the property proximity to Dunas Park or City of the Park entrance increases its price, as does closeness to Dunas Park, view to City of the Park or Dunas Park. On the other hand, selling prices diminish if properties are close to City of the Park or Morro do Careca. Results on this study confirm the hedonic pricing methods is an important intrument, capable of revealing to popullation the importance of enviromental amenities and can be used by public managers for creating public policies for conservation and restoration projects / O valor das amenidades fornecidas por ?reas verdes, o mar, o rio e a paisagem natural s?o dificilmente percebidas e incorporadas no planejamento e desenvolvimento urbano. Neste trabalho foram avaliadas como a dist?ncia e a vista para ?reas verdes urbanas protegidas, n?o protegidas, para o mar e o rio incrementam o valor de resid?ncias em Natal. Foi utilizada a metodologia de pre?os hed?nicos para estimar o valor impl?cito marginal de atributos ambientais, residenciais e urban?sticos atrav?s de modelos lineares. Os resultados do Cap?tulo 1 demonstram que a vista para o mar e para as ?reas naturais protegidas foram amplamente capitalizadas nos pre?os dos im?veis, enquanto que para as ?reas naturais n?o protegidas este efeito n?o foi observado. O pre?o do im?vel tamb?m aumenta se est? pr?ximo ao mar e a entrada de parques. No entanto, os pre?os das habita??es diminuem quando est?o pr?ximas as ?reas naturais n?o protegidas. Quando os im?veis com vista para o mar foram exclu?dos, tanto a vista para a ?rea natural protegida quanto uma maior dist?ncia da ?rea natural n?o protegida aumentaram o pre?o da propriedade. Os resultados do Cap?tulo 2 indicaram que a vista para o mar ? uma vari?vel hed?nica que contribui muito para o pre?o de venda do im?vel, embora nem sempre seja a que mais contribui; ainda, a proximidade do im?vel em rela??o ? entrada do Parque das Dunas ou do Parque da Cidade aumenta o seu pre?o, como tamb?m aumenta se est? pr?ximo ao Parque das Dunas e se tem vista para o Parque da Cidade ou para o Parque das Dunas. Por outro lado, os pre?os de venda diminuem se as propriedades est?o pr?ximas ao Parque da Cidade ou ao Morro do Careca. Os resultados deste estudo confirmam que a metodologia de pre?os hed?nicos ? um instrumento importante capaz de revelar ? popula??o a import?ncia das amenidades ambientais e pode ser utilizada por gestores p?blicos na cria??o de pol?ticas p?blicas para projetos de conserva??o e recupera??o do meio ambiente

Formål: Formålet med denne undersøgelse er at få viden om, og belyse fænomenet seksuel orienterings diskrimination (SOD), og få indsigt i hvordan homoseksuelle mænd, på en mandsdomineret arbejdsplads som det danske Forsvar, oplever SOD og hvilken betydning det har for dem. Desuden er hensigten at få viden om og indsigt i hvordan problematikker vedrørende SOD på en mandsdomineret arbejdsplads, som Forsvaret i Danmark kan imødegås og håndteres. Metode: Transskriberede semi-strukturede dybde interviews er anvendt som undersøgelsesredskab. Teoretisk udvælgelse, kodning, komparation og konceptualisering som beskrevet i ”Grounded Theory” er anvendt som analyseinstrument. Resultater: Ud fra analysen af data voksede en kernekategori og fire hovedkategorier frem, som tilsammen udgør kerneprocessen. Minoritetsstyrkeblev studiets kernekategori, som har sit udspring fra de fire hovedkategorier: Stressorer, Identifikation, Mestring og Miljø. Ud fra resultaterne voksede en Minoritesstyrkemodelfrem. Konklussion: Homoseksuelle mænd håndterer et komplekst udvalg af mestringsstrategier, som anvendes i forskellige situationer hvor diskriminering på baggrund af seksuel orientering finder sted. På trods af de negative minoritetsstressorer, som homoseksuelle mænd i den danske Forsvar erfarer, så udviser informanterne en unik Oplevelse af sammenhæng; Meningsfuldhed; Begribelighedog Håndterbarhed, hvilket leder til Minoritetsstyrke. For at forskningen skal være til gavn for hele befolkningen, så gøres i denne undersøgelse opmærksom på nødvendigheden af at inkludere spørgsmål om seksuel orientering i folkesundhedsvidenskabelig forskning. En inkluderende personale politik, undervisning vedrørende HBT personers vilkår og rekrutteringskampagner specielt rettet mod homoseksuelle, medføre større kompetence blandt alle på arbejdspladsen. Studiet har vist at arbejdet, med at forebygge diskriminering på baggrund af seksuel orientering, kræver en multistrategisk indsats på tværfagligt, intersektorielt niveau og et salutogent perspektiv uden at placere alt ansvar på det enkelte individ / Aim: This study aimed to improve knowledge about and illuminate the phenomenon of sexual orientation discrimination (SOD), particularly as perceived by homosexual men in a male-dominated workplace such as the Danish Armed Forces. We also sought to increase understanding of how such discrimination affects those individuals. Moreover, wesought to increase knowledge about and highlight the challenges and problems regarding SOD in the context of coping strategies. Method: We used transcribed semi-structured in-depth interviews as our survey tool. To analyze our results, we used open, axial, and selective coding, as described in grounded theory. Results: Data analysis allowed us to identify minority power (MP) as a core variable. Further, MP is sourced in the four main categories: stressors, coping, environment, and identity, which are elements of the core process. The MP model that emerged from our results illustrates the core process. Conclusion: The study shows that homosexual men use a complex range of coping strategies in different situations where SOD occurs. Despite the negative minority stressors experienced by homosexual men in the Danish Armed Forces, the subjects showed a unique sense of coherence—meaningfulness, comprehension, and manageability—that leads to MP. To benefit the entire population, this study emphasized the need to include questions about sexual orientation in public health research. The study shows that training about the special social conditions for the LGBT population, a diversity policy, and recruitment campaigns aimed at homosexuals result in greater competence among all individuals in the workplace. Preventing discrimination based on sexual orientation requires a salutogen perspective and multifactorial strategy on an intersectorial and interdisciplinary level without placing all responsibility on the individual / <p>ISBN 978-91-85721-72-6</p>

Doctor Scientiae (Odontology) - DSc(Odont) / Investigations of pathoses of the oral cavity encompass a relatively wide spectrum of diseases, abnormalities, tumours and tumour-like conditions affecting and occurring in the dental hard tissues and supportive structures, the bony skeleton of the face and the soft tissues of the. mouth. It involves a study of the normal - oral biology - and the abnormal - oral pathology. Oral pathology is a relatively new specialized field of dental science and practice. In South Africa, prior to the nineteen-fifties, research in oral pathology was primarily directed towards dental disease. Two people - Julius Staz of the University of the Witwatersrand and Tony Ockerse of the University of Pretoria - were the doyens in this field and made major contributions to dental science. Staz reported on the status of dental caries and tumorous malformations of teeth and Ockerse on the prevalence and severity of fluorosis in South Africa. During the fifties a second generation of dental surgeons, who were interested in soft tissue, bone and tumour pathology, emerged. They ,were Bertie Cohen, George Baikie, Mervyn Shear and John Lemmer who, at that time, were all from the University of the Witwatersrand. Bertie Cohen later joined the Royal College of Surgeons of England. Mervyn Shear led the field with his research on cysts of the oral cavity. The practice of oral pathology, moulded on anatomical pathology, was established in the early sixties and Mervyn Shear and the author, from the University of Pretoria, became known as oral pathologists. Research at that early stage comprised clinical and histological observations of oral lesions, diseases, tumours and tumour-like conditions. Observation techniques became more sophisticated during the sixties and seventies with the advent of histochemistry and electronmicroscopy. The next major development which blossomed in the seventies and early eighties was the application of epidemiological methods in the study of disease. Epidemiological principles enabled the correct recording of profiles of oral pathoses in the community. Much was learnt about the prevalence and distribution of oral conditions. The application and use of experimental models, especially laboratory animals, became popular in the eighties. Amongst others, a germfree animal unit was established in the Faculty of Dentistry of the University of Stellenbosch enabling workers to study the microbiological aetiology of dental and oral disease. Morphological observations of tumours and mucosal lesions were further enhanced during this period with the development of immunocytochemistry Experimental cell studies by means of cell culture techniques, commenced late in the eighties and was established in the early nineties. These models fostered molecular biology techniques which have become useful tools for the investigation of the aetiology of disease at a cellular and molecular level. At present molecular techniques are also popular in other spheres of oral pathology such as microbiological, immunological and oncological research. The author's first contact with oral pathology as a subject, forming an important and interesting part of dentistry, was the prescribed textbook "Oral and Dental Diseases", 2nd ed., 1951., by HH Stone of the University of Liverpool in the United Kingdom. Subsequently an enduring interest in the subject and research was cultivated by three teachers and colleagues, Ivor Kramer, Robert Bradlow and Mervyn Shear. Ivor Kramer, Professor of Oral Pathology in the Eastman Dental Institute of the University of London was a superb postgraduate teacher of oral pathology, and revelled in research. The Dean of the Institute, Professor Sir Robert Bradlow was a clinician and splendid diagnostician. He correlated the clinical and histopathological features of oral diseases. These two teachers set the course in oral pathology for the author during his postgraduate studies. In the sixties, after a spell at the University of Pretoria, the author joined Professor Mervyn Shear at the University of Witwatersrand. It was here that the author could further his skills of presenting lectures and research papers in an orderely manner and strengthen his love of research. The research carried out by the author reflects to a large extent the development of research in oral pathology in South Africa since 1960.. It includes studies of diseases and lesions of the oral mucosa, the dental hard tissues, tumours of the oral cavity and jaws and forensic odonto-stomatology. To date 139 articles have been published and accepted in scientific journals of which I was the first or co-author. The research presented here, however, comprises only those studies related to pathoses of the oral mucosa as it occurs in South Africa. Fifty-four papers and two abstracts are submitted. The papers are grouped into two divisions which include studies on (I) normal human oral and ectocervical mucosa and (II), those related to pathoses of the oral mucosa. The latter is subdivided into sections on: the profile of lesions of the oral mucosa in the community; cytological, clinical and morphological features of lesions of the oral mucosa; and studies on the aetiology of lesions of the oral mucosa. Each division and section is preceded by a declaration as to the contribution of the author or co-authors and a précis of the aims, objects and research findings. In the introduction of the précis statements are made explaining the aims of the study. These statements are not referenced because they appear in the respective articles.

No description available.

Habitat degradation, fragmentation and loss are important factors causing loss in biodiversity and red listed species, and restoring habitats is essential in preventing this. However, there is a limited knowledge of the long term effects of restoration measures. This study focuses on analysing the long term restoration success of restoration measures carried out in a restoration program between the 1980's and early 2000's in locations of acidic fen, buffered fen, dry heather, wet heather, and wet grassland. The aim of the restoration program was to diminish the effects on ecosystems that were influenced by eutrophication, acidification, and dehydration. The locality species composition and Ellenberg values of nitrogen (EVN), moisture (EVM) and pH levels (EVpH) are analysed, by using previous and current restoration success scores from 54 locations in the province of Drenthe in the Netherlands. The dependence of restoration success score and Ellenberg values on change over time, habitat type, restoration method and EVN, EVM and EVpH are analysed. Restoration success depended on habitat type, with wet heather having significantly higher success compared to wet grasslands. The change in score over time, however, did not vary among habitats. Restoration success did not depend on restoration method(s), nor did change in restoration success. Ellenberg values varied among habitat types, and EVM changed significantly over time in dry heather, but was not significantly related to restoration success score. In conclusion, wet heather was shown to be doing quite well, but could benefit from additional restoration. Acidic fen, buffered fen, dry heather, and wet grassland have all shown poor long term restoration effects, indicating an overall need for further restoration measures. The results also highlight the importance of further studies into the effect of long term restorations, especially focused on finding successful restoration methods, and the importance of detailed data gathered in the field.