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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

The Theme of Transcendence in Georg Simmel's Social Theory

McTaggart, John Mitchell 09 1900 (has links)
<p>This thesis is both an extension and a critique of Roy Hornosty's doctoral dissertation. In " Conceptions of Human Nature in the Sociological Tradition", Hornosty traces the development and career of two distinct concepts of human nature as they are reflected in sociological theory. Hornosty argues that sociology originally emerged with two competing ideas of man, one stressing the logical priority of the individual, and the other, the predominance of the collective.</p> <p>In the course of his study, Hornosty discusses what he refers to as the second generation of European sociologists, comprised suggests of Durkheim, Weber, Simmel that each theorist of this and Pareto. Hornosty generation describes a conception of human nature based on an 'inner dialectic' between the individual, who seeks independent self-actualization, over and against the demands of the collective, which develops according to laws which are often in stark contrast to the dictates of individuality.</p> <p>One chapter of Hornosty's study is devoted to Georg Simmel's sociological thought. In it, Hornosty argues that Simmel views man in terms of an antinomy between social and individual forces, locked in an irreconcilable struggle. For Simmel, Hornosty believes, man is both social and, at the same time, independent of society, although never completely. According to Hornosty's interpretation of Simmel, this dialectic is an ineradicable condition of mankind.</p> <p>The present study focuses entirely on the writings of Georg Simmel. The author argues that while an undeniable dialectic exists between the individual and society, it is by no means irreconcilable as Hornosty and others have suggested. In fact, it will be argued that Simmel saw ways in which the dichotomous relationship between the individual and the collective could be overcome.</p> <p>The author contends that Simmel, influenced by Nietzsche's philosophy, details avenues of consequence removed from the sociological nexus. By focusing on Simmel 's four categories of human experience, two of which are completely removed from the social paradigm, this thesis outlines Simmel's attempt to find a manner in which certain talented individuals could transcend the dichotomy between the individual and society through devotion to objective goals which lie beyond the dialectic.</p> <p>The author suggests that Simmel in fact reserves his highest praise for the creative genius, the individual able to tolerate, and in turn, transcend the tensions of his or her existence in the name of a higher good, whether artistic or intellectual. By outlining Simmel's preoccupation with the creative process, and his search for viable expressions of individuality removed from society, the author attempts to illustrate the limitations of the sociological paradigm.</p> / Thesis / Master of Arts (MA)
102

The Implications of Multiple Stellar Formation Events for the Evolution of Globular Clusters

Downing, Jonathan M. B. 07 1900 (has links)
<p> In this thesis we investigate the dynamical effect of a second generation of stellar formation in globular clusters in the context of the anomalous horizontal branch of NGC 2808. The horizontal branch of NGC 2808 is bifurcated in colour and exhibits an extended blue tail. This morphology can be explained if the blue tail stars have an enhanced helium content due to cluster self-enrichment. Specifically it has been proposed that NGC 2808 has experienced two distinct generations of star formation. The first generation has a top-heavy IMF, enhanced in 3 - 5Mo stars, and would produce many AGB stars within the first 200 Myrs of its life. The second generation then forms out of the helium-rich ejecta of the AGB stars and goes on to produce the blue tail in the horizontal branch that is currently observed in NGC 2808.</p> <p> We use three types of simulations to investigate this scenario. For a control model we run a simulation with a Salpeter IMF and a single generation. We then run models with a top-heavy IMF and a single generation and models with a top-heavy IMF and two generations. In the two generation models we also investigate the effect of concentration by examining simulations with two different length scales.</p> <p> We find that the models with the top-heavy IMF and a single generation are subject to extensive mass-loss in their early phases due to the large number of intermediate-mass stars and are less strongly affected by two-body relaxation than simulations with a Salpeter IMF. The models with two generations appear to be dynamically stable and long-lived objects, at least in their early stages. They seem to be observationally indistinguishable from single-generation clusters with Salpeter IMFs on the basis of their dynamics. The stellar populations of the two-generation clusters are found to have a much higher fraction of C-O white dwarfs than clusters with a Salpeter IMF. We find no evidence that these bodies will be preferentially scattered out of the system and they should remain part of the cluster until it dissolves after core collapse. The abundance of white dwarfs would provide an observational method of identifying two generation cluster candidates.</p> <p> Overall we find the two-generation scenario to be plausible on the basis of dynamics but due to the overabundance of white dwarfs produced by the top-heavy IMF and based on other studies of the chemistry of AGB stars we conclude that this scenario is unlikely to be the sole explanation for globular cluster self-enrichment.</p> / Thesis / Master of Science (MSc)
103

An investigation of potential relationships between septic tank microbial communities and system design and performance

Chan, Wing Yip Alexander January 2019 (has links)
Septic tanks are utilized by many households across North America for wastewater treatment. Despite the economic and environmental importance of septic tanks, there has been limited innovation in septic tank design and research on the microbial communities responsible for wastewater treatment within these systems. InnerTube systems are septic tanks that employ a novel design to reduce solid accumulation in comparison to conventional septic tanks. For this project, 16S metabarcoding was employed to characterize conventional and InnerTube septic tank microbial communities and evaluate relationships between community composition, system design, and treatment efficacy. Wastewater was sampled along the length of InnerTubes to determine patterns of microbial succession and how they may impact InnerTube function. Wastewater was separated into liquid and solid fractions to identify differentially abundant taxa in each fraction. Populations of methylotrophic methanogens increased with distance from the InnerTube inlet. Solid communities were differentially more abundant in methanogens than liquid communities. Higher rates of solid degradation in InnerTubes may be due to longitudinal stratification of substrates and functionally distinct communities and the activity of methanogenic biomass. Septic tanks throughout Ontario were also surveyed to evaluate the effect of system design (conventional vs. InnerTube) and operational flow (single-pass vs. recirculation) on microbial community composition and to identify taxa correlated with chemical oxygen demand (COD) reduction. Single-pass InnerTube communities were more abundant in Pseudomonas which was attributed increased availability of long-chain fatty acid substrates. Recirculating conventional communities were more abundant in Arcobacter and Desulfomicrobium which was attributed to greater resistance to oxidative stress. Desulfovibrio and Brevundimonas were positively correlated with COD reduction. These putative hydrogen producers may facilitate greater COD reduction by forming syntrophic relationships with hydrogenotrophic methanogens. The findings of this project may be used to develop bioaugmentation inoculum, system designs, or operational strategies to optimize septic tank performance. / Thesis / Master of Science (MSc) / Septic systems (anaerobic digesters) are extensively used for on-site wastewater treatment. We evaluated the use of next-generation DNA sequencing to (1) assess the variability of septic system microbial communities and (2) to investigate relationships between communities and septic system type/performance. Microbial communities within septic systems were determined to be heterogeneous. Analyses also indicated that communities were highly variable between septic systems. Despite this variability, specific system types exhibited distinct microbial profiles. System performance was positively correlated with the abundance of hydrogen-producing bacteria. These results demonstrate the potential of next-generation DNA sequencing as a new tool to augment traditional wastewater analyses.
104

Konsten att passa in i två världar : En empirisk intervjustudie om mellanförskap, anpassning och identitet bland andra generationens invandrare på arbetsplatsen

Jow, Jatou, Vegdanpak, Nadia January 2023 (has links)
This study aims to deepen the understanding of in-betweenness among individuals belonging to the second generation of immigrants and analyze how this phenomenon influences their identity development and workplace integration. By focusing on the specific population of second-generation immigrants, the paper examines the unique challenges and opportunities these individuals face as they navigate between their heritage culture and the society in which they live. The research approach adopted is abductive. To obtain our findings, we conducted semi-structured interviews with 6 individuals aged 25-40, all belonging to the second generation of immigrants, selected through snowball sampling. The results reveal six overarching themes: background, experience of in-betweenness, challenges in a multicultural environment, workplace policies, adaptation strategies, and future perspectives. The theoretical perspectives highlighted include Social Identity Theory, social constructivism, and acculturation. The findings indicate that interviewees consciously adapt to fit in, and their identity evolves depending on the context. The study also underscores the importance of diversity and inclusion in addressing the sense of in-betweenness, particularly in an environment lacking individuals who resemble oneself or come from a background different from the Swedish norm.
105

Animal models of cognitive dysfunction and negative symptoms of schizophrenia: focus on NMDA receptor antagonism

Neill, Joanna C., Barnes, Samuel, Cook, Samantha, Grayson, Ben, Idris, Nagi F., McLean, Samantha, Snigdha, S., Rajagopal, Lakshmi, Harte, Michael K. 10 August 2010 (has links)
Yes / Cognitive deficits in schizophrenia remain an unmet clinical need. Improved understanding of the neuro- and psychopathology of these deficits depends on the availability of carefully validated animal models which will assist the development of novel therapies. There is much evidence that at least some of the pathology and symptomatology (particularly cognitive and negative symptoms) of schizophrenia results from a dysfunction of the glutamatergic system which may be modelled in animals through the use of NMDA receptor antagonists. The current review examines the validity of this model in rodents. We review the ability of acute and sub-chronic treatment with three non-competitive NMDA antagonists; phencyclidine (PCP), ketamine and MK801 (dizocilpine) to produce cognitive deficits of relevance to schizophrenia in rodents and their subsequent reversal by first- and second-generation antipsychotic drugs. Effects of NMDA receptor antagonists on the performance of rodents in behavioural tests assessing the various domains of cognition and negative symptoms are examined: novel object recognition for visual memory, reversal learning and attentional set shifting for problem solving and reasoning, 5-Choice Serial Reaction Time for attention and speed of processing; in addition to effects on social behaviour and neuropathology. The evidence strongly supports the use of NMDA receptor antagonists to model cognitive deficit and negative symptoms of schizophrenia as well as certain pathological disturbances seen in the illness. This will facilitate the evaluation of much-needed novel pharmacological agents for improved therapy of cognitive deficits and negative symptoms in schizophrenia.
106

Unsicherheiten in der Erfassung des kurzwelligen Wolkenstrahlungseffektes

Hanschmann, Timo 19 March 2014 (has links) (PDF)
Diese Arbeit betrachtet die Wechselwirkung von solarer Einstrahlung mit Wolken in der Atmosphäre. Diese wird insbesondere repräsentiert durch den Wolkenstrahlungseffekt. Hierbei wurde vor allem auf die Auswirkungen von kleinskaliger Variabilität von Wolken und Wolkenfeldern auf die Genauigkeit des Wolkenstrahlungseffektes am Oberrand der Atmosphäre und am Boden Rücksicht genommen. Mit einer Schliessungsstudie ist der modellierte Wolkenstrahlungseffekt mit Schiffsmessungen verglichen worden. Hierbei wurden die Wolkeneigenschaften in dem Modell durch Schiffs- und Satellitendaten als Eingangsdatensatz beschrieben. Ein Zugewinn in der Genauigkeit konnte durch die kombinierte Nutzung beider Datenquellen erzielt werden, konkret durch die Kombination des Flüssigwasserpfads aus Schiffsmessungen und des effektiven Radius aus Satellitenbeobachtungen. Durch die Schliessungsstudie sind zwei Probleme in der Auflösung kleinskaliger Bewölkung und deren Auswirkung auf abgeleitete Wolkeneigenschaften identifiziert worden, die im weiteren Verlauf der Arbeit genauer betrachtet wurden. Ein Vergleich zweier Methoden zur Erkennung des Bedeckungsgrades, jeweils eine vom Boden und eine vom Oberrand der Atmosphäre, hat insgesamt eine gute Übereinstimmung ergeben. Jedoch zeigten sich Abweichungen bei geringer Bedeckung. So wurde bei einem Bedeckungsgrad von ca. 40% in der Hälfte der Fälle den Satellitenbildpunkt als bewölkt klassifiziert. Diese Unsicherheiten in der Klassifikation konnten auf die abgeleitete reflektierte solare Einstrahlung übertragen werden. Für als unbewölkt erkannte, tatsächlich aber bewölkte, Bildpunkte wurde eine mittlere Überschätzung der reflektierte solare Einstrahlung von ca. 30 W/m−2 gefunden. Ebenfalls wurde der Einfluss der zeitlichen Variabilität in der solaren Einstrahlung auf die Bestimmung des Wolkenstrahlungseffektes einer Wolke untersucht. Hierfür wurde ein lineares Modell entwickelt und präsentiert, das die diffuse Einstrahlung mit dem Bedeckungsgrad in Zusammenhang stellt. Das Modell liefert zwei Koeffizienten, die die Variation der diffusen Einstrahlung durch eine Wolke unter der Annahme, dass die beobachtete Wolke den ganzen Himmel bedeckt, beschreiben. Dies ermöglicht einen direkten Vergleich des Wolkenstrahlungseffektes einer beobachteten Wolke mit Modellergebnissen und die Entkopplung von der zeitlich variablen direkten Einstrahlung.
107

Unsicherheiten in der Erfassung des kurzwelligen Wolkenstrahlungseffektes

Hanschmann, Timo 06 February 2014 (has links)
Diese Arbeit betrachtet die Wechselwirkung von solarer Einstrahlung mit Wolken in der Atmosphäre. Diese wird insbesondere repräsentiert durch den Wolkenstrahlungseffekt. Hierbei wurde vor allem auf die Auswirkungen von kleinskaliger Variabilität von Wolken und Wolkenfeldern auf die Genauigkeit des Wolkenstrahlungseffektes am Oberrand der Atmosphäre und am Boden Rücksicht genommen. Mit einer Schliessungsstudie ist der modellierte Wolkenstrahlungseffekt mit Schiffsmessungen verglichen worden. Hierbei wurden die Wolkeneigenschaften in dem Modell durch Schiffs- und Satellitendaten als Eingangsdatensatz beschrieben. Ein Zugewinn in der Genauigkeit konnte durch die kombinierte Nutzung beider Datenquellen erzielt werden, konkret durch die Kombination des Flüssigwasserpfads aus Schiffsmessungen und des effektiven Radius aus Satellitenbeobachtungen. Durch die Schliessungsstudie sind zwei Probleme in der Auflösung kleinskaliger Bewölkung und deren Auswirkung auf abgeleitete Wolkeneigenschaften identifiziert worden, die im weiteren Verlauf der Arbeit genauer betrachtet wurden. Ein Vergleich zweier Methoden zur Erkennung des Bedeckungsgrades, jeweils eine vom Boden und eine vom Oberrand der Atmosphäre, hat insgesamt eine gute Übereinstimmung ergeben. Jedoch zeigten sich Abweichungen bei geringer Bedeckung. So wurde bei einem Bedeckungsgrad von ca. 40% in der Hälfte der Fälle den Satellitenbildpunkt als bewölkt klassifiziert. Diese Unsicherheiten in der Klassifikation konnten auf die abgeleitete reflektierte solare Einstrahlung übertragen werden. Für als unbewölkt erkannte, tatsächlich aber bewölkte, Bildpunkte wurde eine mittlere Überschätzung der reflektierte solare Einstrahlung von ca. 30 W/m−2 gefunden. Ebenfalls wurde der Einfluss der zeitlichen Variabilität in der solaren Einstrahlung auf die Bestimmung des Wolkenstrahlungseffektes einer Wolke untersucht. Hierfür wurde ein lineares Modell entwickelt und präsentiert, das die diffuse Einstrahlung mit dem Bedeckungsgrad in Zusammenhang stellt. Das Modell liefert zwei Koeffizienten, die die Variation der diffusen Einstrahlung durch eine Wolke unter der Annahme, dass die beobachtete Wolke den ganzen Himmel bedeckt, beschreiben. Dies ermöglicht einen direkten Vergleich des Wolkenstrahlungseffektes einer beobachteten Wolke mit Modellergebnissen und die Entkopplung von der zeitlich variablen direkten Einstrahlung.
108

Outside Second-Generation, Inside First-Generation: Shedding Light on a Hidden Population in Higher Education

Bradley, DeMethra LaSha 01 January 2009 (has links)
Second-generation college students comprise a large majority of the collegiate population. The research on this population strongly suggests that their knowledge, capitals, and the support received from their parents gives them a “jump start” in higher education in comparison to their first-generation peers. The positive exposure to higher education received by second-generation college students is asserted to be directly linked to their parents' experiences in higher education. Second-generation college students are assumed to possess the basic knowledge for successful navigation of the college experience. As a second-generation, African-American college student, I carried a high level of expectation and numerous assumptions about what my experiences would be like in the academy. I assumed that my mother's college education would have a positive effect on my college journey. As my college experience unfolded, I found myself severely deficient when it came to basic collegiate knowledge and survival skills. The radical changes in higher education that had occurred during the twenty years between the collegiate experiences of my mother and me greatly decreased my mother's ability to pass on knowledge that was still up-to-date and practical for my experience. My journey through college was nothing like the second-generation student literature suggested. My experiences in higher education closely paralleled those associated with the first-generation student population. The challenges I faced included social, cultural and racial integration, course and major selection, reduced parental involvement and financial strain. I have since come to view myself as a first-generation college student amid second-generation college student assumptions and expectations. Through the use of Scholarly Personal Narrative methodology, this dissertation seeks to bring into focus a hitherto hidden population in higher education. These are the students, who in spite of having at least one parent or guardian with a college degree, do not know how to navigate the college journey; these are the students who feel like imposters in the academy because it is assumed they are better equipped to navigate the institution. In this dissertation I draw upon numerous studies of first-generation and second-generation college students to create an empirical understanding of the dual and dueling narrative I occupied during my undergraduate experience. I explore concepts of cultural and academic capital as being vital in my ability to master the college environment. I introduce for the first time in the literature a concept I call “values capital.” I also discuss the salience of social class identity in the pursuit of higher education in order to frame a narrative of my own self-empowerment and subsequent integration into higher education. In addition to a number of empirical studies, I will draw upon biographies and my own personal narrative to elucidate the universal themes of self-empowerment, authenticity, insecurity, ambition, and meaning-making—themes that all second-generation-on-the-outside but first-generation-on-the-inside students must confront if they are to be successful in higher education.
109

Vietnamští imigranti v České republice - 2. generace / Vietnamese immigrants at Czech Republic - 2nd generation

Sequensová, Kateřina January 2011 (has links)
Second and one-and-half generation of the Vietnamese migrants is a very specific part of the Vietnamese in the Czech Republic. There are several differences between the second and the first generation, i.e. between young Vietnamese and their parents. However, they are similar in many ways. The aim of this master thesis is to discuss the situation of the second and the one-and-half generation of the Vietnamese migrants in the Czech Republic and to show some of the differences between the young generation and the generation of their parents. This work also tries to check some of the well-known claims about the young Vietnamese in the Czech Republic. The work consists of two main parts. The first part is theoretical and it is based on the literature and other scientific resources. It deals with the history of Vietnamese coming to the Czech Republic. It explains how the second generation finds itself in the Czech Republic. There were several waves of the migration and each of them is different in many ways. The work also includes the chapter about the influence on the Confucianism on the Vietnamese education. The influence of the Confucianism on the Vietnamese society can be seen until these days. The education of the Vietnamese children at Czech schools is also mentioned. School is a very important...
110

Estudo do efeito da presença de espécies derivadas do àcido bórico durante pré-tratamento alcalino na sacarificação de palha de soja / Study of the effect of the presence of species derived from boric acid during alkaline pretreatment in the saccharification of soybean straw

Rocha, Alexander Paulo da 15 March 2019 (has links)
Dentre as etapas de produção do etanol de segunda geração tem-se no pré-tratamento da biomassa um dos pontos cruciais, uma vez que a eficiência deste processo está diretamente ligada à maior produção de monossacarídeos fermentáveis após hidrólise e consequentemente maior produtividade de etanol. Dentro deste contexto, no presente trabalho estudou-se o efeito da presença de espécies químicas derivadas do ácido bórico durante pré-tratamento alcalino de palha de soja (matéria-prima abundante no Brasil e ainda inexplorada), visando uma solubilização mais seletiva da lignina em condições brandas, onde a recuperação de carboidratos possa ser superior. Numa primeira etapa estudou-se através de metodologia de superfície de resposta (planejamento composto central) o efeito da concentração inicial de ácido bórico (0,06 a 0,49 mol/l), pH (9,27 a 13,00) e tempo de pré-tratamento (80 min a 280 min) na porcentagem de solubilização da biomassa e recuperação de carboidratos (glicose e xilose) após hidrólise enzimática - experimentos foram conduzidos em temperatura de refluxo. Os resultados mostraram que o tempo não tem efeito significativo dentro do intervalo estudado, e que as superfícies de resposta da porcentagem de solubilização e recuperação de monossacarídeos possuem comportamentos distintos. A máxima recuperação de monossacarídeos pode ser obtida teoricamente utilizando-se 0,33 mol/l de ácido bórico com tendência crescente da resposta conforme se aumenta o pH do meio, enquanto a porcentagem de solubilização indica um crescimento contínuo conforme se aumentam concomitantemente a concentração de ácido bórico e pH. Na melhor condição testada foram obtidos rendimentos de monossacarídeos superiores em 181,2% (glicose) e 507,8% (xilose) com relação à biomassa não tratada. Numa segunda etapa estudou-se comparativamente o pré-tratamento em três valores de pH diferentes (9,27, 11,10 e 13,00) na presença (0,28 mol/l) e ausência de ácido bórico inicial, constatando-se que em todas as condições onde existiam espécies derivadas do ácido bórico (comparadas para um mesmo pH) foram obtidos maiores valores de recuperação de monossacarídeos. Resultados obtidos pelas técnicas de FTIR, TG/DTG, MEV e DRX comprovaram a maior deslignificação em condições onde se tinha ácido bórico inicial presente. Pode-se concluir que a presença de espécies químicas derivadas do ácido bórico (pKa aproximadamente 9,27) em meio alcalino promovem uma maior deslignificação do material lignocelulósico, e que tal comportamento se deve provavelmente à complexação de íons borato (principal íon presente em soluções alcalinas) aos grupos fenólicos da lignina, promovendo desta forma uma maior solubilização e/ou impedindo que fragmentos obtidos da degradação desta se repolimerizem e se depositem novamente sobre a biomassa. / Among the second-generation ethanol production stages, one of the crucial points is the biomass pretreatment since its efficiency is directly linked to the higher production of fermentable monosaccharides after hydrolysis and consequently higher ethanol productivity. In this context, the effect of the presence of boric acid-based chemical species during alkaline pretreatment of soybean straw (a raw material abundant in Brazil and still unexplored) was studied, aiming at a more selective solubilization of lignin in soft conditions, where cellulose and hemicellulose recoveries may be higher. In a first step, the effects of the initial concentration of boric acid (0,06 to 0,49 mol / l), pH (9,27 to 13,00) and pretreatment time (80 min to 280 min) were studied through response surface methodology (central composite design) considering as responses the percentage of biomass solubilization and recovery of monosaccharides (glucose and xylose) after enzymatic hydrolysis - pretreatment experiments were conducted at reflux temperature. The results showed that the time has no significant effect within the range studied, and that the response surfaces of the solubilization and recovery percentage of monosaccharides have different behaviors. The maximum recovery of monosaccharides can be theoretically obtained using 0.33 mol/l of boric acid with increasing tendency as the pH of the medium is increased, while the percentage of solubilization indicates a continuous growth as the boric acid concentration and pH concomitantly increases. In the best tested condition, yields of monosaccharides with 181.2% (glucose) and 507.8% (xylose) were obtained in relation to the crude biomass. In a second step, the pretreatment was studied in three different pH values (9,27, 11,10 and 13,00) in the presence (0,28 mol / l) and absence of boric acid, being verified that in all conditions where boric acid had been added (compared to the same pH) there was a greater recovery of monosaccharides. Results obtained by FTIR, TG / DTG, SEM and XRD showed higher delignification under conditions where boric acid was present. It can be concluded that the presence of boric acid-derived chemical species (pKa approximately 9,27) in alkaline media promotes a greater delignification of the lignocellulosic material, and that this behavior is probably due to the complexation of borate ions (main ion present in alkaline solutions) to the phenolic groups of the lignin, promoting in this way a greater solubilization and / or preventing fragments of this one from being repolymerized and deposited again on the biomass.

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