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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.
31

Ecologically Friendly Food Buying and Recycling: Environmental Attitudes and Behaviors in a Tennessee Survey.

King, Jessica Jane 01 May 2011 (has links) (PDF)
This thesis focuses on pro-environmental attitudes and behaviors and the interactions between recycling behavior, food buying attitudes, food buying behaviors, and ecological beliefs. Following an introductory chapter, I present an article-length paper on recycling behavior to be submitted to Environment and Behavior. Data for this study came from a telephone survey of Tennessee residents (N=270). Using OLS regression analysis, I find that recycling behavior is significantly related to access to recycling facilities. I do not find a significant interaction effect between access to recycling facilities and willingness to recycle. I conclude by suggesting that pro-environmental policies need to make structural resources more available to all in order to promote recycling (and protect the environment in general). Positive attitudes alone do not get us very far. My additional thesis research goal of developing an accurate measure of ecological food buying attitudes and behaviors needs further work.
32

Untersuchungen zur Wirkungsweise von Birkenblättern (Betulae folium) und phenolischer Verbindungen

Major, Hedda 25 March 2002 (has links)
Die Anwendung von Birkenblättern (Betulae folium) erfolgt zur Durchspülung der Harnwege. In der vorliegenden Arbeit wurde die Wirkungsweise der Birkenblätter auf verschiedenen Ebenen der Phytopharmakaforschung untersucht. Zunächst wurde in-vitro die Beeinflussung der Metallopeptidasen Neutrale Endopeptidase (NEP, EC 3.4.24.11), Angiotensin-Converting-Enzym (ACE, EC 3.4.15.1) und Leucin-Aminopeptidase (LAP, EC 3.4.11.2) durch Birkenblätterextrakte, -fraktionen und reine Naturstoffe untersucht. Die Auftrennung eines Methanol- und eines Ethylacetatextraktes führte nicht zur Gewinnung einzelner, für die Gesamtwirkungen der Extrakte verantwortlicher Fraktionen bzw. Komponenten. Die Eigenschaft der Flavonoide als wirksamkeitsmitbestimmende Inhaltsstoffe konnte jedoch bestätigt werden. Ein systematisches Screening von Flavonoiden ergab u.a., dass das Ausmaß der Enzymhemmung von der Anzahl der freien phenolischen OH-Funktionen bestimmt wurde und dass Flavonoidaglyka stärker die Enzyme hemmten, als die im Pflanzenmaterial vorliegenden Glykoside (IC50 NEP: Myricetin 42 Mikromol/L, Quercetin 192 Mikromol/L). Die in der Birkenrinde vorkommenden Triterpene Betulinsäure und Betulinol wurden als starke Inhibitoren der LAP erkannt (IC50 LAP: 7,3 +/- 1,4 bzw. 8,8 +/- 1,78 Mikromol/L). In einem nächsten Abschnitt der Arbeit wurden die Absorptionseigenschaften von Hyperosid und Rutin mit einem In-vitro-Perfusionsmodell am isolierten Rattendünndarm untersucht. Sowohl Rutin als auch Hyperosid traten unverändert als Glykoside durch den Darm in das Akzeptorkompartiment über. Auch in Form eines Birkenblätterextraktes wurde Hyperosid am Rattendünndarm absorbiert, der Extrakt veränderte jedoch nicht die Absorptionsrate. Als Mechanismus wurde der passive Transport durch die Poren der Tight junctions der Dünndarmzellen angenommen. Abschließend wurde eine Pilotstudie (n=14) durchgeführt, in der das ausgeschiedene Harnvolumen nach einmaliger Einnahme eines Birkenblättertees im Vergleich zu einer entsprechenden Menge Leitungswasser bestimmt wurde. Bei 50 % der Probanden wurde innerhalb der vierstündigen Testphase eine Zunahme der Harnproduktion beobachtet, bei den anderen 50 % stellte sich eine gegensätzliche Reaktion auf Tee und Placebo ein. Eine signifikante Erhöhung der Harnproduktion konnte somit, unter dem angegebenen Studiendesign, nicht nachgewiesen werden. / Irrigation of the urinary tract is the therapeutic indication for Birch leaf (Betulae folium). In the present thesis, effects and efficacy of Birch leaves were investigated in various fields of medicinal plant research. The effects of Birch leaf extracts, their fractions, and pure natural compounds on the metallopeptidases - Neutral Endopeptidase (NEP, EC 3.4.24.11), Angiotensin Converting Enzyme (ACE, EC 3.4.15.1), and Leucine Aminopeptidase (LAP, EC 3.4.11.2) - were investigated in vitro. Phytochemical separation of extracts obtained by methanol and ethyl acetate did not result in more active fractions compared to those of the whole extracts. The ability of flavonoids to contribute to the efficacy reached by Birch leaf extracts, could be confirmed. A systematic screening could show that the inhibitory potency of flavonoids is dependent on the number of phenolic hydroxyl functions in their chemical structure. Aglycones of flavonoids were more active than their corresponding glycosides occurring in the plant material (IC50 NEP: myricetin 42 mikromol/L, quercetin 192 mikromol/L). Betulinic acid and betulinol, triterpenes of the bark of Betula, inhibited LAP strongly by reaching an IC50 of 7,3 +/- 1,4 mikromol/L and 8,8 +/- 1,78 mikromol/L, respectively. Furthermore, this thesis showed the absorption profiles of hyperoside and rutin in an isolated small intestine model of the rat. Both glycosides were detected in the acceptor compartment without being metabolised. Administration of hyperoside by a Birch leaf extract did not influence the absorption rate. A passive transport through the pores of the tight junctions, localized between the intestinal cells, was considered to be the mechanism of absorption of the flavonol glycosides. Finally, a human pilot study (n=14) was carried out. The excreted urinary volume was determined after a single intake of a Birch leaf infusion or tap water. An increased urine output after 4 hours of the test period was found in 50% of the volunteers. In the contrary, an opposite effect was determined in 50% of the volunteers after administration of the herbal infusion and of a placebo solution. Thus, no significant increase of urine volume could be observed under these test conditions.
33

Etudes structurales et fonctionnelles des protéines virales impliquées dans le trafic intracellulaire du génome du virus de la grippe

Akarsu, Hatice 09 November 2005 (has links) (PDF)
Le virus de la grippe appartient à la famille des Orthomyxoviridae. Son génome est segmenté en huit ribonucléoprotéines virales (vRNPS) composées chacune d'une molécule d'ARN négatif simple brin recouverte de nucléoprotéines (NP) et associée au complexe de la polymérase. Le virus entre dans<br />la cellule hôte par endocytose, libère dans le cytoplasme ses vRNPs qui gagnent ensuite le noyau cellulaire pour être transcrites et répliquées. Les vRNPs sont importées via l'hétérocomplexe des importines alpha/beta. La NP, composant majoritaire des vRNPs, pourrait être impliquée dans cette étape et serait aussi un candidat idéal dans la mise au point de drogues antivirales. Nous avons voulu déterminer les caractéristiques structurales de <br />NP en complexe avec l'importine alpha 5 humaine. Grâce à la technique de microscopie électronique à transmission, nous avons obtenu un premier <br />modèle à basse résolution du complexe NP/importine alpha.<br />Dans le noyau, les vRNPs sont étroitement liées à la chromatine. En phase tardive du cycle viral, la protéine matricielle M1 se lierait aussi à la chromatine, peut-être pour décrocher les vRNPs. Nous avons pu montrer, par la technique de sédimentation, que les vRNPs se lient aux queues des histones, alors que M1 se fixe sur le domaine globulaire des octamères d'histones.<br />En fin de cycle viral, les vRNPs amplifiées sortent du noyau. Nos tests enzymatiques, d'interaction sur billes et en sédimentation montrent que les protéines virales M1 et NEP servent d'adaptateurs entre les vRNPs et le système d'export nucléaire CRM1/RanGTP. Nous avons aussi obtenu la <br />structure cristallographique du domaine C-terminal de NEP se liant à M1.
34

Environmental Ethics Approach In The World And In Turkey

Yucel (karakoc), A. Gamze 01 December 2005 (has links) (PDF)
This thesis analyzes the environmental knowledge, attitudes and environmentally significant behaviors of the environmental professionals such as academicians and higher level of bureaucrats in Turkey. Additionally socio-demographic characteristics of target groups were measured to examine if environmental professionals having environmental knowledge and defending ecocentric or at least homocentric approaches do really reflect their attitudes and knowledge into actual behaviors or a paradox arises when actual behaviors are compared with expressed beliefs and attitudes. It was found that, socio-demographic characteristics such as gender, age and education were not show statistically significant difference at the respondents&rsquo / behavior. There only exist a positive relationship between education and environmental knowledge. Additionally, the data herein supports the theoretical assumption that, distinct professional groups have different environmental ethical approaches and different levels of environmental knowledge. Academicians have the highest consciousness level of environmental knowledge. Finally the most striking result is / although respondents have at least moderate level of environmental knowledge / there exist a statistically significant negative correlation between respondents&rsquo / environmental knowledge and their behavior.
35

Influência da hidrodinâmica no metabolismo de lagos rasos

Cavalcanti, José Rafael de Albuquerque January 2013 (has links)
Este trabalho parte da hipótese que a hidrodinâmica influencia o metabolismo de um lago. Para testar esta hipótese, este estudo utilizou uma estratégia numérica baseada em processos para avaliar o efeito da hidrodinâmica (governada pelo vento) sobre as estimativas de metabolismo (GPP, NEP e R) considerando a heterogeneidade espacial da lagoa Mangueira, um grande lago raso subtropical na costa sul do Brasil. O efeito da hidrodinâmica dominada pelo vento no metabolismo foi avaliado pela mudança da série de vento original (direção e intensidade), totalizando cinco novos cenários de vento. A avaliação espacial foi desenvolvida em quatro áreas (Norte, Centro, Sul e a lagoa como um todo) e em zonas biológicas (zona limnética e zona litorânea). Os resultados indicaram que há diferenças nas estimativas de metabolismo (GPP, NEP e R) entre as regiões da lagoa Mangueira considerando a situação com a série de vento original. Em geral, a diferença média nas estimativas de metabolismo entre a região Norte e a região Sul foi de 3,81 mgO2/m³/dia (p-value<0,05) para o GPP, 3,32 mgO2/m³/dia para R (p-value<0,05) e 0,49 mgO2/m³/dia (p-value<0,05) para NEP. A diferença entre a zona litorânea e a zona limnética na lagoa Mangueira como um todo foi de 10,1 mgO2/m³/dia para GPP, para R foi de 1,3 mgO2/m³/dia e para NEP foi de 8,8 mgO2/m³/dia. O metabolismo geral da lagoa também apresentou variações sazonais, alternando entre períodos autotróficos (NEP>0, em 41,0 % do tempo) e períodos heterotróficos (NEP<0, em 59,0 % do tempo). As estimativas de metabolismo da Lagoa Mangueira e nas regiões delimitadas se mostraram sensíveis a alterações no vento. Cada área delimitada apresentou resposta diferente às alterações nas séries de vento. Os cenários de vento testados mostram que a hidrodinâmica causa diferenças significativas no metabolismo da Lagoa Mangueira. O balanço de oxigênio neste ecossistema foi influenciado pela taxa de reaeração, pela produção primária e pela respiração do fitoplâncton. Os outros processos considerados no balanço de oxigênio não demonstraram contribuições importantes para o metabolismo geral do ecossistema. / The hypothesis of this work is that hydrodynamics can alter the lake metabolism. To evaluate this hypothesis this study used a process-based strategy for evaluating the effect of wind-driven hydrodynamics on estimates of lake metabolism (GPP, R, and NEP) considering the spatial heterogeneity in Lake Mangueira, a subtropical grate lake in southern coast of Brazil. The effect of wind-driven hydrodynamics over the lake metabolism was evaluated by changes in the original wind series (direction and intensity), totalizing five new sets of wind scenarios. The spatial evaluation was carried in four different areas (North, Center, South, and the lake as a whole) and in two different biological zones (littoral zone and limnetic zone). Our findings indicate that there are differences on estimates of lake metabolism between the four areas taking into account the original wind time series. In general, the differences on lake metabolism estimates between the Norte region and the South region was 3.81 mgO2/m³/day (p-value<0,05) for GPP, 3.32 mgO2/m³/day (p-value<0,05) for R, and 0.49 mgO2/m³/day (p-value<0,05) for NEP. The difference between the littoral zone and the limnetic zone in the Lake Mangueira as a whole was 10.1 mgO2/m³/day for GPP, 1.3 mgO2/m³/day for R, and 8.8 mgO2/m³/day for NEP. The overall lake metabolism also presented seasonal variations, alternating among autotrophic periods (NEP>0, 41.0% of the time), and heterotrophic periods (NEP<0, 59.0% of the time). Estimates of lake metabolism in Lake Mangueira as a whole were sensitive to changes in the wind time series. Each area showed different response to the changes in wind time series. The tested sets of wind scenarios showed that wind-driven hydrodynamics can significantly alter the Lake Mangueira metabolism estimates. The overall oxygen balance in this system was mostly influenced by reaeration, and by the primary production and respiration of phytoplankton. The other processes considered in the oxygen balance showed no significant contributions to the overall metabolism of the ecosystem.
36

Influência da hidrodinâmica no metabolismo de lagos rasos

Cavalcanti, José Rafael de Albuquerque January 2013 (has links)
Este trabalho parte da hipótese que a hidrodinâmica influencia o metabolismo de um lago. Para testar esta hipótese, este estudo utilizou uma estratégia numérica baseada em processos para avaliar o efeito da hidrodinâmica (governada pelo vento) sobre as estimativas de metabolismo (GPP, NEP e R) considerando a heterogeneidade espacial da lagoa Mangueira, um grande lago raso subtropical na costa sul do Brasil. O efeito da hidrodinâmica dominada pelo vento no metabolismo foi avaliado pela mudança da série de vento original (direção e intensidade), totalizando cinco novos cenários de vento. A avaliação espacial foi desenvolvida em quatro áreas (Norte, Centro, Sul e a lagoa como um todo) e em zonas biológicas (zona limnética e zona litorânea). Os resultados indicaram que há diferenças nas estimativas de metabolismo (GPP, NEP e R) entre as regiões da lagoa Mangueira considerando a situação com a série de vento original. Em geral, a diferença média nas estimativas de metabolismo entre a região Norte e a região Sul foi de 3,81 mgO2/m³/dia (p-value<0,05) para o GPP, 3,32 mgO2/m³/dia para R (p-value<0,05) e 0,49 mgO2/m³/dia (p-value<0,05) para NEP. A diferença entre a zona litorânea e a zona limnética na lagoa Mangueira como um todo foi de 10,1 mgO2/m³/dia para GPP, para R foi de 1,3 mgO2/m³/dia e para NEP foi de 8,8 mgO2/m³/dia. O metabolismo geral da lagoa também apresentou variações sazonais, alternando entre períodos autotróficos (NEP>0, em 41,0 % do tempo) e períodos heterotróficos (NEP<0, em 59,0 % do tempo). As estimativas de metabolismo da Lagoa Mangueira e nas regiões delimitadas se mostraram sensíveis a alterações no vento. Cada área delimitada apresentou resposta diferente às alterações nas séries de vento. Os cenários de vento testados mostram que a hidrodinâmica causa diferenças significativas no metabolismo da Lagoa Mangueira. O balanço de oxigênio neste ecossistema foi influenciado pela taxa de reaeração, pela produção primária e pela respiração do fitoplâncton. Os outros processos considerados no balanço de oxigênio não demonstraram contribuições importantes para o metabolismo geral do ecossistema. / The hypothesis of this work is that hydrodynamics can alter the lake metabolism. To evaluate this hypothesis this study used a process-based strategy for evaluating the effect of wind-driven hydrodynamics on estimates of lake metabolism (GPP, R, and NEP) considering the spatial heterogeneity in Lake Mangueira, a subtropical grate lake in southern coast of Brazil. The effect of wind-driven hydrodynamics over the lake metabolism was evaluated by changes in the original wind series (direction and intensity), totalizing five new sets of wind scenarios. The spatial evaluation was carried in four different areas (North, Center, South, and the lake as a whole) and in two different biological zones (littoral zone and limnetic zone). Our findings indicate that there are differences on estimates of lake metabolism between the four areas taking into account the original wind time series. In general, the differences on lake metabolism estimates between the Norte region and the South region was 3.81 mgO2/m³/day (p-value<0,05) for GPP, 3.32 mgO2/m³/day (p-value<0,05) for R, and 0.49 mgO2/m³/day (p-value<0,05) for NEP. The difference between the littoral zone and the limnetic zone in the Lake Mangueira as a whole was 10.1 mgO2/m³/day for GPP, 1.3 mgO2/m³/day for R, and 8.8 mgO2/m³/day for NEP. The overall lake metabolism also presented seasonal variations, alternating among autotrophic periods (NEP>0, 41.0% of the time), and heterotrophic periods (NEP<0, 59.0% of the time). Estimates of lake metabolism in Lake Mangueira as a whole were sensitive to changes in the wind time series. Each area showed different response to the changes in wind time series. The tested sets of wind scenarios showed that wind-driven hydrodynamics can significantly alter the Lake Mangueira metabolism estimates. The overall oxygen balance in this system was mostly influenced by reaeration, and by the primary production and respiration of phytoplankton. The other processes considered in the oxygen balance showed no significant contributions to the overall metabolism of the ecosystem.
37

Influência da hidrodinâmica no metabolismo de lagos rasos

Cavalcanti, José Rafael de Albuquerque January 2013 (has links)
Este trabalho parte da hipótese que a hidrodinâmica influencia o metabolismo de um lago. Para testar esta hipótese, este estudo utilizou uma estratégia numérica baseada em processos para avaliar o efeito da hidrodinâmica (governada pelo vento) sobre as estimativas de metabolismo (GPP, NEP e R) considerando a heterogeneidade espacial da lagoa Mangueira, um grande lago raso subtropical na costa sul do Brasil. O efeito da hidrodinâmica dominada pelo vento no metabolismo foi avaliado pela mudança da série de vento original (direção e intensidade), totalizando cinco novos cenários de vento. A avaliação espacial foi desenvolvida em quatro áreas (Norte, Centro, Sul e a lagoa como um todo) e em zonas biológicas (zona limnética e zona litorânea). Os resultados indicaram que há diferenças nas estimativas de metabolismo (GPP, NEP e R) entre as regiões da lagoa Mangueira considerando a situação com a série de vento original. Em geral, a diferença média nas estimativas de metabolismo entre a região Norte e a região Sul foi de 3,81 mgO2/m³/dia (p-value<0,05) para o GPP, 3,32 mgO2/m³/dia para R (p-value<0,05) e 0,49 mgO2/m³/dia (p-value<0,05) para NEP. A diferença entre a zona litorânea e a zona limnética na lagoa Mangueira como um todo foi de 10,1 mgO2/m³/dia para GPP, para R foi de 1,3 mgO2/m³/dia e para NEP foi de 8,8 mgO2/m³/dia. O metabolismo geral da lagoa também apresentou variações sazonais, alternando entre períodos autotróficos (NEP>0, em 41,0 % do tempo) e períodos heterotróficos (NEP<0, em 59,0 % do tempo). As estimativas de metabolismo da Lagoa Mangueira e nas regiões delimitadas se mostraram sensíveis a alterações no vento. Cada área delimitada apresentou resposta diferente às alterações nas séries de vento. Os cenários de vento testados mostram que a hidrodinâmica causa diferenças significativas no metabolismo da Lagoa Mangueira. O balanço de oxigênio neste ecossistema foi influenciado pela taxa de reaeração, pela produção primária e pela respiração do fitoplâncton. Os outros processos considerados no balanço de oxigênio não demonstraram contribuições importantes para o metabolismo geral do ecossistema. / The hypothesis of this work is that hydrodynamics can alter the lake metabolism. To evaluate this hypothesis this study used a process-based strategy for evaluating the effect of wind-driven hydrodynamics on estimates of lake metabolism (GPP, R, and NEP) considering the spatial heterogeneity in Lake Mangueira, a subtropical grate lake in southern coast of Brazil. The effect of wind-driven hydrodynamics over the lake metabolism was evaluated by changes in the original wind series (direction and intensity), totalizing five new sets of wind scenarios. The spatial evaluation was carried in four different areas (North, Center, South, and the lake as a whole) and in two different biological zones (littoral zone and limnetic zone). Our findings indicate that there are differences on estimates of lake metabolism between the four areas taking into account the original wind time series. In general, the differences on lake metabolism estimates between the Norte region and the South region was 3.81 mgO2/m³/day (p-value<0,05) for GPP, 3.32 mgO2/m³/day (p-value<0,05) for R, and 0.49 mgO2/m³/day (p-value<0,05) for NEP. The difference between the littoral zone and the limnetic zone in the Lake Mangueira as a whole was 10.1 mgO2/m³/day for GPP, 1.3 mgO2/m³/day for R, and 8.8 mgO2/m³/day for NEP. The overall lake metabolism also presented seasonal variations, alternating among autotrophic periods (NEP>0, 41.0% of the time), and heterotrophic periods (NEP<0, 59.0% of the time). Estimates of lake metabolism in Lake Mangueira as a whole were sensitive to changes in the wind time series. Each area showed different response to the changes in wind time series. The tested sets of wind scenarios showed that wind-driven hydrodynamics can significantly alter the Lake Mangueira metabolism estimates. The overall oxygen balance in this system was mostly influenced by reaeration, and by the primary production and respiration of phytoplankton. The other processes considered in the oxygen balance showed no significant contributions to the overall metabolism of the ecosystem.
38

Fungal bioactive molecules in interactions with plants and animals

Su, Ling 15 October 2019 (has links)
No description available.
39

WHAT'S THE STORY? UNCOVERING THE ENVIRONMENTAL IDENTITIES OF COLLEGE STUDENTS

GARRISON, AUTUMN L. 02 October 2006 (has links)
No description available.
40

Characterization of Room Temperature Terahertz Direct Detectors

Boggs, Carla Renee 14 December 2011 (has links)
No description available.

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