• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 47
  • 26
  • 16
  • 8
  • 4
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 118
  • 13
  • 11
  • 11
  • 10
  • 10
  • 10
  • 9
  • 9
  • 9
  • 9
  • 9
  • 8
  • 8
  • 8
  • 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.
41

Propriedades funcionais e estruturais e concentração de fosfatos orgânicos em eritrócitos de dez espécies de morcegos pertencentes às famílias Phyllostomidae e Molossidae (Chiroptera - Mammalia).

Reinoso, Simoni Savazzi 19 December 2003 (has links)
Made available in DSpace on 2016-06-02T20:20:35Z (GMT). No. of bitstreams: 1 TeseSSR.pdf: 4068903 bytes, checksum: 04896bfbefd0027002928519a22c3786 (MD5) Previous issue date: 2003-12-19 / Universidade Federal de Minas Gerais / Hemoglobin structural and functional aspects, as well as the presence of intraerythrocitic organic phosphates of 167 individuals of 10 species of bats, belonging to Phyllostomidae (Artibeus planirostris, Phyllostomus discolor, Artibeus lituratus, Carollia perspicillata, Desmodus rotundus, Glossophaga soricina), and Molossidae family (Molossus ater, Molossus molossus, Nyctinomops laticaudatus e Eumops perotis) were studied. These individuals were collected in different areas of São Paulo State. Hemoglobin of these individuals were submitted to starch gel electrophoresis and showed all the same pattern: one slow major, migrating close to A2 human hemoglobin and one minor fast component, migrating close to human hemoglobin A. No intra and inter specific variation were detected. Variations on functional properties in blood were detected. Most of the species (7) presented normal Bohr effect, while C. perspicillata, D. rotundus e M. molossus null Bohr effect. Artibeus planirostris presented reverse Bohr effect. All the hemoglobin samples showed normal Bohr effect in the stripped form as well as in the presence of 2,3-biphospho glicerate and inositol hexaphosphate. The addition of this organic phosphate has altered both Bohr effect and P50 values. The oxygen affinities were high in all hemoglobins. In vivo, the oxygen affinity of bat hemoglobins is lower due to modulator effect,probably ,3.biphospho glicerate. In the erythrocytes of all individuals studied 2,3-biphospho glycerate were found in varying concentrations and a little higher than most of Mammals. No inositol polyphosphates were found in any sample tested. / Foram estudados aspectos estruturais e funcionais da hemoglobina, bem como, a presença dos fosfatos orgânicos em 163 indivíduos de 10 espécies de morcegos pertencentes à família Phyllostomidae (Artibeus planirostris, Phyllostomus discolor, Artibeus lituratus, Carollia perspicillata, Desmodus rotundus, Glossophaga soricina), e Molossidae (Molossus ater, Molossus molossus, Nyctinomops laticaudatus e Eumops perotis). Essas espécies foram coletadas em regiões diferentes do estado de São Paulo. Através de eletroforese em gel de amido, foram detectado nas 10 espécies estudadas, dois componentes hemoglobínicos, um componente maior, de mobilidade próxima à hemoglobina A2., e outro menor, de mobilidade próxima a da Hb A humana. Não foi detectada qualquer variação intra ou interespecífica. Foram detectadas, variações nas propriedades funcionais do sangue. A maioria (7) das espécies apresentou efeito Bohr normal, enquanto que C. perspicillata, D. rotundus e M. molossus apresentou efeito Bohr nulo. Artibeus planirostris apresentou efeito Bohr reverso. Todas as espécies apresentaram hemoglobina com efeito Bohr normal na forma stripped, bem como na presença dos moduladores 2,3-bifosfoglicerato e inositol hexafosfato . A adição desses fosfatos orgânicos alterou tanto amplitude do efeito Bohr quanto os valores de P50. A afinidade ao oxigênio das hemoglobinas stripped das espécies estudadas é alta, sendo diminuída, in vivo, por ação de moduladores, provavelmente o 2,3,bifosfoglicerato. Nos eritrócitos de todas as espécies estudadas mostraram 2,3.bifosfoglicerato em concentrações que variaram dependendo da espécie, mas levemente superiores à da maioria dos mamíferos. Não foi detectado qualquer tipo de inositol polifosfatado nos eritrócitos das espécies estudadas.
42

The health knowledge mechanism: evidence on the link between education and health lifestyle in the Philippines

Hoffmann, Roman, Lutz, Sebastian Uljas 03 January 2018 (has links) (PDF)
Studies have found substantial differences in health-related behavior and health care usage between educational groups, which may explain part of the well-documented educational gradient in health. The allocative efficiency hypothesis offers a behavioral explanation for these reported differences. According to this theory, the educated possess more health knowledge and information, allowing them to make better health choices. We perform a mediation analysis to study this mechanism using original survey data from the Philippines, a lower-middle-income country. As an extension of previous empirical research, we construct a comprehensive index that captures different dimensions of health knowledge. Using generalized propensity scores, we find strong support for the allocative efficiency argument. Schooling is significantly associated with health knowledge levels, which explain up to 69% of the education effect on health lifestyle. This corresponds to twice the mediation strength of economic resources, suggesting an important role of this factor in explaining education effects on health decisions.
43

Simulations aux grandes échelles de la phase d'allumage dans un moteur fusée cryotechnique

Rocchi, Jean-Philippe 12 September 2014 (has links) (PDF)
À ses débuts, la conquête spatiale a pu bénéficier des rivalités politiques de la Guerre Froide pour se développer rapidement sans réellement se soucier des efforts économiques à fournir. Aujourd’hui, de nombreux pays subissent le revers de la médaille de cette course effrénée : pour maintenir une flotte de lanceurs viable économiquement, les différentes agences spatiales doivent faire face à un dilemme opposant la minimisation des coûts de lancement à la maximisation de leur fiabilité. Dans cette logique d’optimisation, les industriels présents dans ce processus de réflexion se tournent vers la simulation numérique pour tenter d’améliorer leurs connaissances des technologies existantes, en particulier sur les zones d’ombres inaccessibles aux mesures expérimentales. Dans la lignée de plusieurs études théoriques et expérimentales, ces travaux visent à apporter un éclairage nouveau sur les phénomènes se produisant lors de l’allumage d’un moteur fusée cryotechnique. Ces recherches se tournent dans un premier temps vers l’amélioration de la modélisation de la flamme H2/O2. La validation d’une cinétique chimique réduite initialement destinée à la combustion H2/Air permet de justifier son utilisation lors de l’allumage. Puis, le développement d’un modèle de combustion turbulente pour le régime de flamme de diffusion est mené dans le but de palier aux limitations du modèle de flamme épaissie. Enfin, une analyse du cas où les régimes prémélangés et non-prémélangés sont présents tous les deux permet d’étudier un moyen simple de les distinguer même dans le cas où ils sont très proches. Dans un second temps, ces travaux se tournent vers l’étude de l’allumage dans un moteur fusée cryotechnique. Après avoir analysé de manière globale le calcul d’une séquence simplifiée, deux études plus approfondies sont menées pour investiguer, d’une part, les différents régimes de combustion, et d’autre part, les différents modes de propagation de la flamme propres à cette configuration.
44

Water splitting by heterogeneous catalysis

Svengren, Henrik January 2017 (has links)
A sustainable solution for meeting the energy demands at our planet is by utilizing wind-, solar-, wave-, thermal-, biomass- and hydroelectric power. These renewable and CO2 emission-free energy sources are highly variable in terms of spatial and temporal availability over the Earth, introducing the need for an appropriate method of storing and carrying energy. Hydrogen has gained significant attention as an energy storage- and carrier media because of the high energy density that is exploited within the ‘power-to-gas’ process chain. A robust way of producing sustainable hydrogen is via electrochemical water splitting. In this work the search for new heterogeneous catalyst materials with the aim of increasing energy efficiency in water splitting has involved methods of both electrochemical water splitting and chemical water oxidation. Some 21 compounds including metal- oxides, oxofluorides, oxochlorides, hydroxide and metals have been evaluated as catalysts. Two of these were synthesized directly onto conductive backbones by hydrothermal methods. Dedicated electrochemical cells were constructed for appropriate analysis of reactions, with one cell simulating an upscale unit accounting for realistic large scale applications; in this cell gaseous products are quantified by use of mass spectrometry. Parameters such as real time faradaic efficiency, production of H2 and O2 in relation to power input or overpotentials, Tafel slopes, exchange current density and electrochemical active surface area as well as turnover numbers and turnover frequencies have been evaluated. Solubility, possible side reactions, the role of the oxidation state of catalytically active elements and the nature of the outermost active surface layer of the catalyst are discussed. It was concluded that metal oxides are less efficient than metal based catalysts, both in terms of energy efficiency and in terms of electrode preparation methods intended for long time operation. The most efficient material was Ni-Fe hydroxide electrodeposited onto Ni metal foam as conductive backbone. Among the other catalysts, Co3Sb4O6F6 was of particular interest because the compound incorporate a metalloid (Sb) and redox inert F and yet show pronounced catalytic performance. In addition, performance of materials in water splitting catalysis has been discussed on the basis of results from electron microscopy, solubility experiments and X-ray diffraction data.
45

Analýza mobilního trhu v České republice a na Slovensku

Burianová, Monika January 2008 (has links)
Diplomová práce ?Analýza mobilního trhu v České republice a na Slovensku? se věnuje detailnímu rozboru trhů s mobilními technologiemi v těchto dvou zemích. Jejím hlavním cílem je vypracování přehledné a ucelené analýzy mobilního trhu v ČR a na Slovensku především z pohledu klíčových hráčů a tržního prostředí, a provedení srovnání těchto dvou trhů.
46

The Interactions of Plasma with Low-k Dielectrics: Fundamental Damage and Protection Mechanisms

Behera, Swayambhu Prasad 08 1900 (has links)
Nanoporous low-k dielectrics are used for integrated circuit interconnects to reduce the propagation delays, and cross talk noise between metal wires as an alternative material for SiO2. These materials, typically organosilicate glass (OSG) films, are exposed to oxygen plasmas during photoresist stripping and related processes which substantially damage the film by abstracting carbon, incorporating O and OH, eventually leading to significantly increased k values. Systematic studies have been performed to understand the oxygen plasma-induced damage mechanisms on different low-k OSG films of various porosity and pore interconnectedness. Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy and atomic force microscopy are used to understand the damage kinetics of O radicals, ultraviolet photons and charged species, and possible ways to control the carbon loss from the film. FTIR results demonstrate that O radical present in the plasma is primarily responsible for carbon abstraction and this is governed by diffusion mechanism involving interconnected film nanopores. The loss of carbon from the film can be controlled by closing the pore interconnections, He plasma pretreatment is an effective way to control the damage at longer exposure by closing the connections between the pores.
47

Optická kontrola skleněného polotovaru / Visual inspection of transparent products

Matus, Gabriel January 2014 (has links)
This project deals with the optical control of welding glass blank. The blank consists two small parts of made of special glass. This blank is an essential part of the measuring device density of oxygen. Measuring device algorithm is based on paramagnetic properties of oxygen. It is a small and precise piece of the whole mechanism therefore the precision and perfection made strict criteria. For checking compliance with those criteria, developed a computer program written in C# programming language. Its task is to rule on perfection produced parts. It also serves to back up data on individual production units.
48

Hodnocení finanční situace podniku a návrhy na její zlepšení / Evaluation of the Financial Situation in the Firm and Proposals to its Improvement

Vykydalová, Petra January 2009 (has links)
The thesis deals with assessing the financial health of Telefónica O2 Czech Republic, a.s. by using selected financial analysis tools. It is divided into four sections – evaluation of the current problems, theoretical background, analysis of problems of the current situation and their own proposals for solution. In evaluation of the current problems are formulated objectives to tackle the problem together with the basic characteristics of society. The theoretical part, containing the findings from the literature, clarifies and describes selected methods of financial analysis which are subsequently used in next part of the processing of financial analysis of Telefónica O2 Czech Republic, a.s. The result of the financial analysis is an assessment of the financial health of the company during the years 2005 – 2008 and proposals to solve problems arising from it.
49

Vliv původu a strategie chovu na nutriční hodnotu produkovaných lososovitých ryb.

Trybulovský, Filip January 2018 (has links)
In my work, I was dealing with the influence of the origin and strategies of breeding of produced salmonid fish on the nutrition value of the muscle. Rainbow trout, brook trout and interspecific hybrid of Salvelinus alpinus and S. fontinalis were analyzed. Two feed tests were performed. Both tests were carried out in an experimental recirculating system at the Department of Fisheries and Hydrobiology at the Mendel University in Brno. Length-weight parameters of fish were measured, from which individual indices, production and conditional parameters were subsequently calculated. In addition, the yield and viscerosomatic index were determined. The content of fat, proteins and dry matter of the fish muscle was determined and used for nutrition value evaluation. The effect of reduced oxygen saturation (below 70 %) compared to normal oxygen saturation (around 100 %) was also analyzed in the first test. In Test 1, feedstuff Biomar Efico Enviro 920, Focus Plus with the addition of immunostimulants and Advance with a higher proportion of plant components were used. No statistically significant differences in production and conditional parameters, length-weight ratios and yields were registered for these feeds. The highest percentage of fat content in the muscle (7.66 %) was in fish fed Focus Plus. The dry matter and protein content of the muscle was similar. The greatest effect of reduced O2 was noticed in the fat content of the muscle. For a group of fish fed Efico Enviro 920, it was statistically significant (p = 0.03 and 0.042). Yield values were higher in a group with reduced oxygen saturation. This could be the result of lower intake of feed at the reduced O2 and lower amount of internal fat. In Test 2, the largest difference was recorded in the percentage production of fish. The highest increase was achieved by rainbow trout in Var. 1 (238.8 %) and the lowest increase was achieved by brook trout in Var. 4 (122.43 %). No statistical significant differences in production and length-weight parameters were registered. The highest yield was recorded in the hybrid (88.47 %) in Var. 5.
50

Rechargeable Potassium-Oxygen Battery for Low-Cost High-Efficiency Energy Storage

Ren, Xiaodi, Ren 20 December 2016 (has links)
No description available.

Page generated in 0.0651 seconds