• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 3
  • 2
  • 1
  • Tagged with
  • 12
  • 12
  • 5
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 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.
1

Zpracování projektu tepelného solárního systému / Project of the solar heating system

Pořízka, Jaromír January 2008 (has links)
The diploma thesis studies the elaboration of project about thermal solar systém for all- season service. System is used for heating of outdoor pool and in the winter season for the heating of nearby garage in the village Lipůvka. The aim of the work was to make a proportioning, choosing the right parts and calculating the economic and ecologic balance.
2

Zpracování projektu tepelného solárního systému / Project of the solar heating system

Ullmann, Walter January 2011 (has links)
The diploma thesis studies the elaboration of project about thermal solar systém for all- season service. The aim of the work was to make a proportioning, choosing the right parts and calculating the economic and ecologic balance.
3

Zpracování projektu kombinovaného solárního systému / Processing of the project combined solar system

Sučková, Tereza January 2013 (has links)
The diploma thesis studies the elaboration of project about optimization of solar system for all- season service. The aim of the work was to make a proportioning, choosing the right parts and finding the economic and ecologic balance.
4

Medições do saldo de radiação em copas de cafeeiros e limeiras ácidas por sistemas de integração espaço-temporal e estimativas por técnicas de modelagem / Measurements of net radiation of the canopy of coffee and acid lime trees in hedgerows by spatiotemporal integration systems and estimates by modelling techniques

Simon, Jones 16 June 2010 (has links)
A energia radiante absorvida pelas copas tem aplicação em estudos de fotossíntese e transpiração de plantas arbóreas. Sua determinação não é simples. Nas últimas duas décadas tem sido realizados trabalhos sobre interceptação de radiação por espécies arbóreas isoladas ou em renques, envolvendo tanto radiação de ondas curtas como de ondas longas (saldo de radiação, Rn). Uma técnica de medida de Rn utiliza radiômetros movendo-se em torno da copa de uma árvore (geometria esférica de medida) ou ao longo de copas de um renque (geometria cilíndrica). Uma alternativa é o uso de modelagem físico-matemática para estimativa de Rn, que também exige medidas para testar modelos. Considerando os poucos trabalhos nessa linha de pesquisa, o presente estudo objetivou: a) avaliar o desempenho de sistemas móveis de integração espaçotemporal de medidas de Rn em renque de um cafezal e de um pomar de limeira ácida localizados no Campus Luiz de Queiroz, USP, Piracicaba, SP; b) estabelecer relações do saldo de radiação das copas de cafeeiros (Rnc) e limeiras ácidas (Rnl) com o saldo de radiação de gramado (Rng) e irradiância solar global (Rg); c) avaliar o desempenho de três modelos físicomatemáticos de estimativa de Rn por comparação com as medidas realizadas com varredura da copa pelos saldo-radiômetros movimentando-se ao longo dos renques (geometria cilíndrica de medidas). Os estudos foram realizados nas quatro estações do ano e em três no pomar, iniciandose respectivamente no outono e no verão de 2008. Os sistemas integradores forneceram valores diários de magnitude coerentes com os de calor latente de vaporização da copa determinados por medidas de transpiração de uma árvore. O desempenho do sistema de grande porte utilizado no pomar exige testes adicionais. O curso diário de Rn em cada posição dos radiômetros em torno da copa mostraram padrões diferenciados conforme orientação do renque e época do ano. No cafezal foram encontradas muito boas relações de Rnc com Rg e Rng nas escalas de 15min, horária e diurna, exceto no verão para 15min e horária e no inverno, na escala diurna, para Rng. Para o pomar, as relações de Rnl com Rg e Rng foram boas nas três escalas temporais, exceto no verão para 15min e horária e no outono na escala diurna. Para o cafezal o modelo de Beer apresentou altos índices de confiabilidade nas épocas do ano, nas escalas horária e diurna; e no pomar se mostrou confiável para inverno, mas não no verão na escala diurna e na escala horária apresentou menor confiabilidade. O modelo de Pilau apresentou boa confiabilidade para o cafezal no outono e menor confiabilidade nas demais estações, enquanto na escala horária verificou-se boa confiabilidade no outono e inverno; para o pomar, o desempenho foi satisfatório para inverno nas duas escalas temporais e insatisfatório para verão na escala diurna. Para o cafezal o modelo de Oyarzun mostrou-se confiável na escala diurna, e menos confiável na escala horária no verão; para o pomar, apresentou boa confiabilidade em ambas escalas temporais no inverno e baixa confiabilidade no verão. / The amount of radiant energy absorbed by the canopy of trees has great application in photosynthesis and transpiration research. Studies of radiation interception by the canopies of an isolated or a sequence of trees in hedgerows have been carried out by a technique which employs moving radiometers around an isolated tree (spherical geometry of measurement) or along a part of a hedgerow (cylindrical geometry). This technique allows spatiotemporal integration of the values. Crop Modeling is an alternative approach to estimate the radiation balance of canopies (Rn). The present study had the following objectives: a) to evaluate the performance of systems for spatiotemporal integration of Rn measurements in hedgerows of a coffee and an acid lime crops at the Luiz de Queiroz Campus of the University of São Paulo, in Piracicaba, SP, Brazil; b) to establish relations of the net radiation of the coffee (Rnc) and of acid lime plants (Rnl) canopies with grass net radiation (Rng) and incoming solar radiation (Rg); c) to evaluate the performance of three models of Radiation Balance (Rn), by comparing modem results with measurements by the moving radiometers along the planting row (cylindrical geometry). The coffee experiment was carried out all year long starting in the fall of 2008 while for the orchard only three seasons were tested starting in the summer 2008. Measurements of Rn by the moving systems were considered reliable, but it is recommended further testing of that of the orchard. The daily course of Rn for each measurement around the canopy showed different patterns for the two crops, in agreement with planting row orientation and season. Concerning to relations of Rnc with Rg and Rng integrated for 15min, hourly and diurnal periods, they were very good for the coffee crop in the three timescales, excepting for the 15min and hourly timescales in the summer and for the Rng for the diurnal period in the winter. For the orchard, the relations of Rnl with Rg and Rng were good, excepting for the summer in the 15min and hourly and in autumn for the diurnal timescales. The Beer´s model showed good reliability for the coffee crop; while for the orchard it showed to be reliable in the winter, but not in the summer for the diurnal period; for the hourly periods it was less reliable. The Pilau´s model showed good reliability for the coffee crop for both the diurnal and hourly periods during the fall, but less reliability in the other seasons; for the orchard, its performance was reliable for the winter in the two timescales and not reliable for the summer in the diurnal scale. The Oyarzun´s model showed to be reliable in the diurnal timescale and less reliable in the hourly timescale for the summer; for the orchard, it showed good reliability for the winter and little reliability for the summer.
5

Ingestão de dieta hiperlipídica rica em óleo de peixe aumenta o gasto energético independentemente de UCP1. / Intake of diet enriched fish oil increases energy expenditure by a UCP1-independent mechanism and protects mice from obesity induced by lard-rich diet.

Silva, Tiago Eugênio Oliveira da 04 May 2018 (has links)
Estudos realizados em nosso laboratório encontraram que o aumento do conteúdo corporal de ácidos graxos N3, pela produção endógena via modificação genética, protege camundongos do ganho de peso corporal e obesidade induzida por dieta hiperlipídica. Objetivo: Investigar os mecanismos pelos quais o óleo de peixecontrola o balanço energético de camundongos C57BL6/J e UCP1selvagens e Knockout (KO) protegendo do desenvolvimento da obesidade induzida por dieta, com ênfase nos processos termogênicos dependentes e independentes da UCP1. Materiais e Métodos: Protocolo 1- Camundongos C57BL6/J alimentados por 8 semanas com dieta normal (DN) contendo 10% de lipídeos oriundos do óleo de soja e banha de porco, dieta normal N3 (DNN3) contendo 10% de lipídeos oriundos do óleo de soja e óleo de peixe, dieta hiperlipídica (HFD) contendo 60% de lipídeos oriundos do óleo de soja e banha de porco e dieta hiperlipídica (HFDN3) contendo 60% de lipídeos oriundos do óleo de soja e óleo de peixe foram avaliados para o peso corporal, a eficiência energética, a ingestão alimentar, a calorimetria indireta, a adiposidade, a tolerância à glicose e à insulina, o consumo de oxigênio tecidual e a análise lipidômica do tecido adiposo inguinal (TAI) e marrom (TAM). Protocolo 2- Camundongos selvagens e Knockout para a UCP1 alimentados por 8 semanas com dieta (HFD) e (HFDN3) foram avaliados para o peso corporal, a eficiência energética, a ingestão alimentar, a calorimetria indireta, a adiposidade, a tolerância à glicose, e o consumo de oxigênio tecidual. Resultados: Protocolo 1- Não houve diferenças significativas no ganho de peso, adiposidade, ingestão alimentar, consumo de oxigênio e tolerância à glicose entre camundongos C57BL6/J alimentados com as dietas DN e DNN3. Entretanto, aqueles alimentados com dieta HFDN3, apresentaram reduzido ganho de peso corporal, massa dos tecidos adiposos e eficiência energética quando comparados a camundongos alimentados com dieta HFD. Esses efeitos aconteceram na ausência de alterações significativas na ingestão alimentar medida tanto em gramas quanto em Kcal entre esses grupos. Corroborando a menor eficiência energética, camundongos C57BL6/J alimentados com dieta HFDN3 apresentaram maior consumo de oxigênio e similar atividade locomotora espontânea que camundongos alimentados com dieta HFD. Demonstramos que o consumo de oxigênio do TAI foi maior no grupo HFDN3 quando comparado ao grupo HFD. Por fim, a análise lipidômica do TAI e TAM revelou que a principal modificação ocorreu no enriquecimento dos triacilgliceróis (TAG) desses tecidos, sobretudo um aumento de ácidos graxos altamente insaturados (HUFA) nos TAG de camundongos alimentados com dieta HFDN3. Protocolo 2- Demonstramos que a dieta HFDN3 protege os camundongos UCP1 KO contra o ganho de peso corporal, aumenta o gasto energético e melhora à tolerância à glicose de maneira independente da UCP1. Além disso, observamos que o grupo UCP1 KO HFD aumentou a massa do TAM quando comparado aos outros grupos. Conclusão: A substituição da banha de porco pelo óleo de peixe na dieta aumenta o gasto energético de camundongos reduzindo o ganho de peso corporal e a adiposidade de maneira independente da UCP1. Digno de nota, o enriquecimento dos TAG com HUFA, pode ser um importante fenótipo para respostas observadas no balanço energético do grupo HFDN3 de ambos os protocolos. Acreditamos, em parte, que uma alta mobilização dos HUFA para a beta-oxidação possa estar acontecendo em paralelo com a ativação de vias alternativas de gasto energético. Os mecanismos responsáveis por estas ações serão investigados futuramente. / We have previously shown that diet-induced obesity is prevented by increasing N3 fatty acids content in the body of mice through genetic modification. Aim: In the present study, we investigated the mechanisms by which the fish oil control the energy balance protecting mice from diet-induced obesity, with emphasis at shivering and non-shivering thermogenesis. Materials and Methods: Protocol 1- C57BL6/J mice were fed during 8 weeks with normal diet (DN) containing 10% of lipids from soy oil and lard, normal diet N3 (DNN3) containing 10% of lipids from soy and fish oils, high fat diet (HFD) 60% of lipids from soy oil and lard and high fat diet (HFDN3) containing 60% of lipids from soy and fish oils. The evaluated parameters were body weight, energy efficiency, food intake, indirect calorimetry, adiposity, glucose and insulin tolerance, tissue oxygen consumption and lipidomic analysis of the white adipose tissue (WAT) and brown adipose tissue (BAT). Protocol 2- Wild type (WT) and UCP1 knockout (KO) mice were fed during 8 weeks with HFD and HFDN3. In Protocol 2, body weight, energy efficiency, food intake, indirect calorimetry, adiposity, glucose tolerance and tissue oxygen consumption were evaluated. Results: Protocol 1- No significant differences were observed in body weight, adiposity, food intake, oxygen consumption and glucose tolerance between mice fed with DN and DNN3. Mice fed with HFDN3, however, displayed reduced body weight gain, epididimal, inguinal and retroperitoneal adipose tissue masses, and energy efficiency when compared to mice fed with HFD. These effects occurred in the absence of significant alterations in food intake measured in grams and Kcal. Corroborating the decrease in energy efficiency, C57BL6/J mice fed with HFDN3 have increased oxygen consumption, but similar spontaneous locomotor activity when compared to mice fed with HFD. We show that oxygen consumption in the WAT in mice fed with HFDN3 was higher than in mice fed with HFD. Finally, the lipidomics analysis in both WAT and BAT revealed an enrichment of the triacylglycerol (TAG) linked to highly unsaturated fatty acids (HUFA, 46 double bonds) in mice fed with HFDN3. Protocol 2- The HFDN3 protects both WT and UCP1 KO groups from body weight gain, increases energy expenditure, and improves glucose tolerance. Moreover, we observe that UCP1 KO HFD group increased the weight of the TAM relative to the other groups. Conclusion: Our results indicate that replacement of lard by fish oil in the diet of mice increases energy expenditure independently of UCP1, decreasing the gain in body weight and adiposity in both protocols. To account for these findings, a model based on the higher mobilization of TAG linked to HUFA for beta-oxidation (relative to less unsaturated moieties) and activation of alternative mechanisms of energy expenditure are proposed to explain the lean phenotype of mice fed with HFDN3. This and other mechanisms of energy expenditure, however, require further investigations.
6

Medições do saldo de radiação em copas de cafeeiros e limeiras ácidas por sistemas de integração espaço-temporal e estimativas por técnicas de modelagem / Measurements of net radiation of the canopy of coffee and acid lime trees in hedgerows by spatiotemporal integration systems and estimates by modelling techniques

Jones Simon 16 June 2010 (has links)
A energia radiante absorvida pelas copas tem aplicação em estudos de fotossíntese e transpiração de plantas arbóreas. Sua determinação não é simples. Nas últimas duas décadas tem sido realizados trabalhos sobre interceptação de radiação por espécies arbóreas isoladas ou em renques, envolvendo tanto radiação de ondas curtas como de ondas longas (saldo de radiação, Rn). Uma técnica de medida de Rn utiliza radiômetros movendo-se em torno da copa de uma árvore (geometria esférica de medida) ou ao longo de copas de um renque (geometria cilíndrica). Uma alternativa é o uso de modelagem físico-matemática para estimativa de Rn, que também exige medidas para testar modelos. Considerando os poucos trabalhos nessa linha de pesquisa, o presente estudo objetivou: a) avaliar o desempenho de sistemas móveis de integração espaçotemporal de medidas de Rn em renque de um cafezal e de um pomar de limeira ácida localizados no Campus Luiz de Queiroz, USP, Piracicaba, SP; b) estabelecer relações do saldo de radiação das copas de cafeeiros (Rnc) e limeiras ácidas (Rnl) com o saldo de radiação de gramado (Rng) e irradiância solar global (Rg); c) avaliar o desempenho de três modelos físicomatemáticos de estimativa de Rn por comparação com as medidas realizadas com varredura da copa pelos saldo-radiômetros movimentando-se ao longo dos renques (geometria cilíndrica de medidas). Os estudos foram realizados nas quatro estações do ano e em três no pomar, iniciandose respectivamente no outono e no verão de 2008. Os sistemas integradores forneceram valores diários de magnitude coerentes com os de calor latente de vaporização da copa determinados por medidas de transpiração de uma árvore. O desempenho do sistema de grande porte utilizado no pomar exige testes adicionais. O curso diário de Rn em cada posição dos radiômetros em torno da copa mostraram padrões diferenciados conforme orientação do renque e época do ano. No cafezal foram encontradas muito boas relações de Rnc com Rg e Rng nas escalas de 15min, horária e diurna, exceto no verão para 15min e horária e no inverno, na escala diurna, para Rng. Para o pomar, as relações de Rnl com Rg e Rng foram boas nas três escalas temporais, exceto no verão para 15min e horária e no outono na escala diurna. Para o cafezal o modelo de Beer apresentou altos índices de confiabilidade nas épocas do ano, nas escalas horária e diurna; e no pomar se mostrou confiável para inverno, mas não no verão na escala diurna e na escala horária apresentou menor confiabilidade. O modelo de Pilau apresentou boa confiabilidade para o cafezal no outono e menor confiabilidade nas demais estações, enquanto na escala horária verificou-se boa confiabilidade no outono e inverno; para o pomar, o desempenho foi satisfatório para inverno nas duas escalas temporais e insatisfatório para verão na escala diurna. Para o cafezal o modelo de Oyarzun mostrou-se confiável na escala diurna, e menos confiável na escala horária no verão; para o pomar, apresentou boa confiabilidade em ambas escalas temporais no inverno e baixa confiabilidade no verão. / The amount of radiant energy absorbed by the canopy of trees has great application in photosynthesis and transpiration research. Studies of radiation interception by the canopies of an isolated or a sequence of trees in hedgerows have been carried out by a technique which employs moving radiometers around an isolated tree (spherical geometry of measurement) or along a part of a hedgerow (cylindrical geometry). This technique allows spatiotemporal integration of the values. Crop Modeling is an alternative approach to estimate the radiation balance of canopies (Rn). The present study had the following objectives: a) to evaluate the performance of systems for spatiotemporal integration of Rn measurements in hedgerows of a coffee and an acid lime crops at the Luiz de Queiroz Campus of the University of São Paulo, in Piracicaba, SP, Brazil; b) to establish relations of the net radiation of the coffee (Rnc) and of acid lime plants (Rnl) canopies with grass net radiation (Rng) and incoming solar radiation (Rg); c) to evaluate the performance of three models of Radiation Balance (Rn), by comparing modem results with measurements by the moving radiometers along the planting row (cylindrical geometry). The coffee experiment was carried out all year long starting in the fall of 2008 while for the orchard only three seasons were tested starting in the summer 2008. Measurements of Rn by the moving systems were considered reliable, but it is recommended further testing of that of the orchard. The daily course of Rn for each measurement around the canopy showed different patterns for the two crops, in agreement with planting row orientation and season. Concerning to relations of Rnc with Rg and Rng integrated for 15min, hourly and diurnal periods, they were very good for the coffee crop in the three timescales, excepting for the 15min and hourly timescales in the summer and for the Rng for the diurnal period in the winter. For the orchard, the relations of Rnl with Rg and Rng were good, excepting for the summer in the 15min and hourly and in autumn for the diurnal timescales. The Beer´s model showed good reliability for the coffee crop; while for the orchard it showed to be reliable in the winter, but not in the summer for the diurnal period; for the hourly periods it was less reliable. The Pilau´s model showed good reliability for the coffee crop for both the diurnal and hourly periods during the fall, but less reliability in the other seasons; for the orchard, its performance was reliable for the winter in the two timescales and not reliable for the summer in the diurnal scale. The Oyarzun´s model showed to be reliable in the diurnal timescale and less reliable in the hourly timescale for the summer; for the orchard, it showed good reliability for the winter and little reliability for the summer.
7

The EnergyKids Pilot Study: Comparing Energy Balance of Primary School Children during School and Summer Camp

Franchini, Cinzia, Rosi, Alice, Ricci, Cristian, Scazzina, Francesca 21 April 2023 (has links)
Children’s energy requirements may vary during school and summer camp days. To evaluate energy balance during these two periods, seventy-eight children (45% females, 8–10 years) living in Parma, Italy, were enrolled in this observational study. Participants completed a 3-day food diary and wore an activity tracker for three consecutive days during a school- and a summer camp-week to estimate energy intake (EI) and energy expenditure (TEE). Height and body weight were measured at the beginning of each period to define children’s weight status. BMI and EI (school: 1692 ± 265 kcal/day; summer camp: 1738 ± 262 kcal/day) were similar during both periods. Both physical activity and TEE (summer camp: 1948 ± 312; school: 1704 ± 263 kcal/day) were higher during summer camp compared to school time. Therefore, energy balance was more negative during summer camp (−209 ± 366 kcal/day) compared to school time (−12 ± 331 kcal/day). Similar results were observed when males and females were analyzed separately but, comparing the sexes, males had a higher TEE and a more negative energy balance than females, during both periods. The results strongly suggest that an accurate evaluation of children’s energy balance, that considers both diet and physical activity, is needed when planning adequate diets for different situations.
8

Zum Einfluss von Witterung und Klima auf den Landschaftszustand und die Landschaftsentwicklung im Uvs-Nuur-Becken (NW-Mongolei)

Barsch, Andreas January 2003 (has links)
Im Landschaftszustand und in der Landschaftsentwicklung kommen funktionale Beziehungen zwischen dem naturbedingten Energie-, Wasser- und Stoffhaushalt einerseits und den Auswirkungen der Landnutzung andererseits zum Ausdruck. Gegenwärtig verändert der globale Anstieg der bodennahen Temperaturen vielerorts den landschaftlichen Energie-, Wasser- und Stoffhaushalt, wobei besonders in Trockengebieten zu erwarten ist, dass dieser Trend in Verbindung mit einer unangepassten Landnutzung das Regenerationsvermögen der Vegetation einschränkt und zur Zerstörung der Bodendecke führt.<br /> <br /> Für die Mongolei und für benachbarte Gebiete Asiens sind in Szenarien zur globalen Erwärmung hohe Werte des Temperaturanstiegs prognostiziert worden. Eine globale Einschätzung der anthropogen induzierten Bodendegradation hat diese Region als stark oder extrem stark betroffen eingestuft. Vor diesem Hintergrund wurde im Uvs-Nuur-Becken, das im Nordwesten der Mongolei und damit in einer der trockensten Regionen des Landes gelegen ist, untersucht, wie sich der globale Temperaturanstieg auf der lokalen und regionalen Ebene widerspiegelt und wie der Landschaftshaushalt dabei verändert wird.<br /> <br /> Die Auswirkungen des sommerlichen Witterungsverlaufes auf den Landschaftszustand sind 1997 bis 1999 an einem Transsekt erfasst worden, das sich zwischen dem Kharkhiraa-Gebirge am Westrand des Beckens und dem See Uvs Nuur im Beckeninneren von den Polsterfluren und Matten der alpinen Stufe über die Gebirgswaldsteppe, die Trockensteppe bis zur Halbwüste erstreckt. An neun Messpunkten wurden witterungsklimatische Daten in Verbindung mit Merkmalen der Vegetation, des Bodens und der Bodenfeuchte aufgenommen. Die im Sommer 1998 gewonnenen Messwerte wurden mit Hilfe einer Clusteranalyse gebündelt und verdichtet. Auf dieser Grundlage konnten landschaftliche Zustandsformen inhaltlich gekennzeichnet, zeitlich eingeordnet und durch Zeit-Verhaltens-Modelle (Stacks) abgebildet werden. Aus den Zeit-Verhaltens-Modellen wird ersichtlich, dass man Zustandsformen, in denen die Hitze und die Trockenheit des Sommers 1998 besonders stark zum Ausdruck kommen, an allen Messpunkten beobachten kann, nimmt man die Station auf dem fast 3.000 m hohen Gipfel des Khukh Uul sowie die grundwasserbeeinflusste Station in unmittelbarer Seenähe aus. In ihrer extremen Form sind Trockenperioden jedoch nur im Beckeninneren und am Fuß der Randgebirge, also in der Halbwüste, in der Trockensteppe und in der Wiesensteppe aufgetreten. Im Bergwald sowie im Bereich der alpinen Matten und Polsterfluren fehlen sie.<br /> <br /> Am stärksten sind die grundwasserfreien Bereiche der Halbwüste von der Hitze und Niederschlagsarmut des Sommers 1998 betroffen. An vier Fünfteln der Tage des Beobachtungszeitraumes herrscht an diesem Messpunkt extreme Trockenheit. Es fällt entweder gar kein Niederschlag oder nur so wenig, dass der seit dem Frühjahr erschöpfte Bodenwasservorrat nicht aufgefüllt wird. Das Verhältnis zwischen Niederschlag und potenzieller Verdunstung liegt hier bei 1:12.<br /> <br /> In der Halbwüste zeichnet sich eine fortschreitende Desertifikation ab, zumal hier eine nichtangepasste Weidenutzung dominiert, in der Ziegen eine immer größere Rolle spielen. Dies gilt insbesondere für Bereiche in Siedlungsnähe. Örtlich ist auch der Bestand der Trockensteppe gefährdet, die sich an die Halbwüste zum Beckenrand hin anschließt. Hier ist nicht nur die Viehdichte am höchsten, sondern hier werden auch die meisten unbefestigten Fahrwege wild angelegt und die Bodendecke damit zerstört. Dies kann im Endeffekt zu einem Übergreifen von Prozessen der Desertifikation führen.<br /> <br /> Aus methodischer Sicht zeigt sich, dass die Kennzeichnung landschaftlicher Zustandsformen durch Zeit-Verhaltens-Modelle die Ermittlung der Auswirkungen von Witterung und Klima auf den Landschaftszustand erleichtert, da sie deren Aussage konzentriert. Zur Interpretation der Ergebnisse ist jedoch ein Rückgriff auf die beschreibende Darstellung der Messwerte notwendig. Die im westlichen Uvs-Nuur-Becken und seinen Randgebirgen angewandte Verfahrensweise ermöglicht es, globale Aussagen zur globalen Erwärmung der Kontinente regional oder lokal zu überprüfen und zu untersetzen." / Landscape condition and landscape development express the functional relations between energy balance, water balance and material balance on the one hand and on the other hand they reflect the effects of land use. At present the global increase of near-surface air temperature changes the energy balance, water balance and material balance in many places. Especially in arid regions this trend and an inappropriate land use restrict the regeneration ability of vegetation and lead to the degradation of soil cover.<br /> <br /> Different scenarios for global warming prognosticate high values of increasing air temperature in Mongolia and its adjacent regions in Asia. A global estimation of anthropogenicly induced soil degradation classifies this region as strongly or extremely strong affected. Against this background a research was carried out in the Uvs Nuur Basin, placed in the northwest of Mongolia and therefore in one of the most arid regions of this country. The object of investigation was the reflection of the global increase of air temperature on a local and regional level and the resulting changes of landscape balance.<br /> <br /> From 1997 to 1999 the effects of changes in summer weather on the landscape condition were measured on a transect from the Kharkhiraa mountains at the western margin of the basin up to the lake Uvs at the centre of the basin. The transect included alpine mat, mountain steppe, dry steppe and semi desert. Climatic data was collected at 9 transect stations, in addition with characteristics of vegetation, soil and soil moisture. The data of summer 1998 was bundled and consolidated with a cluster analysis. On this basis forms of landscape condition could be evaluated in content, arranged chronologically and characterised by time performance models (stacks).<br /> <br /> The time performance models prove that forms of landscape condition marking the heat and the drought of summer 1998 can be found at every station of the transect except of the one on the summit of Khukh Uul at almost 3.000 m above sea level and another groundwater-influenced station at the bank of lake Uvs. However, extremely dry periods occur only from the centre of the basin up to the foothills, thus in the semi desert, the dry steppe and the short grass steppe. They do not occur in the mountain forest and in the alpine mat.<br /> <br /> Areas in the semi desert are most affected by drought and lack of precipitation during the summer 1998. Four fifths of the days in the measurement period are extremely droughty days. Either there is no precipitation at all or it is insufficient to fill up the soil water storage exhausted since spring-time. The relation of precipitation and potential evaporation averages out here at 1:12.<br /> <br /> A progressive desertification becomes apparent in the semi desert, particularly determined by an inappropriate land use in conjunction with an increasing goat-rearing in the area around the settlements. Partially this trend even affects the dry steppe in adjacency to the semi desert toward the margin of the basin. These areas are characterised not only by the highest stocking rate but also by the largest number of unofficial dirt roads thus leading to the denudation of the soil cover and finally to the spreading of desertification processes.<br /> <br /> From the methodical point of view it is obvious that the characterisation by time performance models facilitates the determination of weather and climate influence on landscape condition by summarising their information. However, the interpretation of the results has to be accomplished by a describing analysis of the measured data. The procedure applied in the western Uvs Nuur Basin and its adjacent mountains provides the opportunity to examine and substantiate the reports on global warming at regional or local level.
9

High protein dietary patterns and Type 2 diabetes.

Pearce, Karma Louise January 2008 (has links)
By the year 2025, it is anticipated that over 300 million individuals world wide will have type 2 diabetes, with a projected increase from 84 to 288 million (170%) in developing countries and from 51 to 72 million (42%) in developed countries. Diabetes leads to a markedly increased risk of heart disease and renal failure and to expensive and debilitating retinopathy and neuropathy. Cognitive decline is also increased. As there is accumulating evidence of the beneficial effects of moderate carbohydrate, low fat dietary patterns compared to high carbohydrate diets, this thesis will focus on the effects of moderate carbohydrate high protein dietary patterns (total carbohydrate: protein: fat ratio of 40%:34%:26%) on glycemic control, risk factors for macrovascular disease and cognitive function. Information on two key areas in type 2 diabetes will be presented, 1. Acute effects of dietary patterns, moderately carbohydrate restricted and high in protein on glucose levels assessed using continuous glucose monitoring systems (CGMS) with verification of these results through a small repeat study. 2. Chronic effects of energy restricted dietary patterns, moderately carbohydrate restricted and high in protein on glucose levels, HbA1c, cognitive function, cardiovascular disease (CVD) risk markers and renal function. In the acute study, we recruited 23 subjects with type 2 diabetes. The participants were randomized to each of 4, 3-day interventions in a cross over design with a 4 day wash out period in which the carbohydrates were distributed differently at each meal; carbohydrates evenly distributed across the day, or carbohydrates loaded at breakfast, lunch or dinner. Glucose levels were continuously measured using CGMS. Outcomes were assessed by postprandial peak glucose (Gmax), time spent above 12 mmol/L (T>12) and total area under the glucose curve (AUC20). The intervention showed that an even distribution of carbohydrates did not optimise blood glucose control, whereas carbohydrates loaded at the lunch time meal provided the most favourable postprandial profile. To verify these results we conducted a repeat study. Six of the previous participants accepted the invitation to return and complete the even distribution arm of the study after a 20 week time lag. The intervention showed that although HbA1c, fasting blood glucose (FBG), AUC, exercise and ambient temperature remained constant there was a significant effect of change in sunlight hours on Gmax, suggesting an effect of sunlight. To assess the chronic effects of energy restricted dietary patterns on the determinants of HbA1c, cognitive function, CVD risk markers and renal function under conditions of weight loss, we recruited 82 participants with type 2 diabetes. These participants were randomised to one of two high protein energy restricted dietary patterns that differed in cholesterol content, for a 12 week period, in a parallel design. A sub group of these participants completed cognitive function testing with (n=34) or without (n=17) CGMS at baseline and at 8 weeks. After 8 weeks of the intervention the determinants of HbA1c under conditions of energy restriction were evaluated. The intervention showed the change in FBG accounted for most of the variance in change in HbA1c, but % energy reduction also contributed independently of FBG. Both energy restricted high protein diets equally improved glycemic control, particularly T>12, AUC, HbA1c and FBG. Fifty one participants completed cognitive testing to evaluate the effect of weight loss and blood glucose control on cognition. Cognitive function was not altered by time, diet, baseline lipid levels. Working memory was predicted by FBG. Short term memory was predicted by FBG, Gmax and AUC24. Sixty five participants completed 12 weeks of the intervention to assess CVD risk markers and renal function. Renal function was maintained and CV markers improved on both dietary patterns, with greatest improvement in HDL-C observed in the group consuming a high protein, energy restricted dietary pattern, high in dietary cholesterol. In conclusion, in the context of a high protein, carbohydrate restricted dietary pattern, cognitive function and renal function did not change, while glycemia and CV risk profiles improved with weight loss over the short term. Under conditions of energy balance diurnal glucose profiles were optimal when the carbohydrates were loaded in the lunch meal. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1342253 / Thesis (Ph.D.) - University of Adelaide, School of Molecular and Biomedical Science, 2008
10

High protein dietary patterns and Type 2 diabetes.

Pearce, Karma Louise January 2008 (has links)
By the year 2025, it is anticipated that over 300 million individuals world wide will have type 2 diabetes, with a projected increase from 84 to 288 million (170%) in developing countries and from 51 to 72 million (42%) in developed countries. Diabetes leads to a markedly increased risk of heart disease and renal failure and to expensive and debilitating retinopathy and neuropathy. Cognitive decline is also increased. As there is accumulating evidence of the beneficial effects of moderate carbohydrate, low fat dietary patterns compared to high carbohydrate diets, this thesis will focus on the effects of moderate carbohydrate high protein dietary patterns (total carbohydrate: protein: fat ratio of 40%:34%:26%) on glycemic control, risk factors for macrovascular disease and cognitive function. Information on two key areas in type 2 diabetes will be presented, 1. Acute effects of dietary patterns, moderately carbohydrate restricted and high in protein on glucose levels assessed using continuous glucose monitoring systems (CGMS) with verification of these results through a small repeat study. 2. Chronic effects of energy restricted dietary patterns, moderately carbohydrate restricted and high in protein on glucose levels, HbA1c, cognitive function, cardiovascular disease (CVD) risk markers and renal function. In the acute study, we recruited 23 subjects with type 2 diabetes. The participants were randomized to each of 4, 3-day interventions in a cross over design with a 4 day wash out period in which the carbohydrates were distributed differently at each meal; carbohydrates evenly distributed across the day, or carbohydrates loaded at breakfast, lunch or dinner. Glucose levels were continuously measured using CGMS. Outcomes were assessed by postprandial peak glucose (Gmax), time spent above 12 mmol/L (T>12) and total area under the glucose curve (AUC20). The intervention showed that an even distribution of carbohydrates did not optimise blood glucose control, whereas carbohydrates loaded at the lunch time meal provided the most favourable postprandial profile. To verify these results we conducted a repeat study. Six of the previous participants accepted the invitation to return and complete the even distribution arm of the study after a 20 week time lag. The intervention showed that although HbA1c, fasting blood glucose (FBG), AUC, exercise and ambient temperature remained constant there was a significant effect of change in sunlight hours on Gmax, suggesting an effect of sunlight. To assess the chronic effects of energy restricted dietary patterns on the determinants of HbA1c, cognitive function, CVD risk markers and renal function under conditions of weight loss, we recruited 82 participants with type 2 diabetes. These participants were randomised to one of two high protein energy restricted dietary patterns that differed in cholesterol content, for a 12 week period, in a parallel design. A sub group of these participants completed cognitive function testing with (n=34) or without (n=17) CGMS at baseline and at 8 weeks. After 8 weeks of the intervention the determinants of HbA1c under conditions of energy restriction were evaluated. The intervention showed the change in FBG accounted for most of the variance in change in HbA1c, but % energy reduction also contributed independently of FBG. Both energy restricted high protein diets equally improved glycemic control, particularly T>12, AUC, HbA1c and FBG. Fifty one participants completed cognitive testing to evaluate the effect of weight loss and blood glucose control on cognition. Cognitive function was not altered by time, diet, baseline lipid levels. Working memory was predicted by FBG. Short term memory was predicted by FBG, Gmax and AUC24. Sixty five participants completed 12 weeks of the intervention to assess CVD risk markers and renal function. Renal function was maintained and CV markers improved on both dietary patterns, with greatest improvement in HDL-C observed in the group consuming a high protein, energy restricted dietary pattern, high in dietary cholesterol. In conclusion, in the context of a high protein, carbohydrate restricted dietary pattern, cognitive function and renal function did not change, while glycemia and CV risk profiles improved with weight loss over the short term. Under conditions of energy balance diurnal glucose profiles were optimal when the carbohydrates were loaded in the lunch meal. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1342253 / Thesis (Ph.D.) - University of Adelaide, School of Molecular and Biomedical Science, 2008

Page generated in 0.0947 seconds