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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

A review of neurohormone GPCRs present in the fruitfly Drosophila melanogaster and the honey bee Apis mellifera

Blenau, Wolfgang, Hauser, Frank, Cazzamali, Guiseppe, Williamson, Michael, Grimmelikhuijzen, Cornelis J. P. January 2006 (has links)
G protein-coupled receptor (GPCR) genes are large gene families in every animal, sometimes making up to 1-2% of the animal's genome. Of all insect GPCRs, the neurohormone (neuropeptide, protein hormone, biogenic amine) GPCRs are especially important, because they, together with their ligands, occupy a high hierarchic position in the physiology of insects and steer crucial processes such as development, reproduction, and behavior. In this paper, we give a review of our current knowledge on Drosophila melanogaster GPCRs and use this information to annotate the neurohormone GPCR genes present in the recently sequenced genome from the honey bee Apis mellifera. We found 35 neuropeptide receptor genes in the honey bee (44 in Drosophila) and two genes, coding for leucine-rich repeats-containing protein hormone GPCRs (4 in Drosophila). In addition, the honey bee has 19 biogenic amine receptor genes (21 in Drosophila). The larger numbers of neurohormone receptors in Drosophila are probably due to gene duplications that occurred during recent evolution of the fly. Our analyses also yielded the likely ligands for 40 of the 56 honey bee neurohormone GPCRs identified in this study. In addition, we made some interesting observations on neurohormone GPCR evolution and the evolution and co-evolution of their ligands. For neuropeptide and protein hormone GPCRs, there appears to be a general co-evolution between receptors and their ligands. This is in contrast to biogenic amine GPCRs, where evolutionarily unrelated GPCRs often bind to the same biogenic amine, suggesting frequent ligand exchanges ("ligand hops") during GPCR evolution. (c) 2006 Elsevier Ltd. All rights reserved.
32

Environmental impacts of early metallurgy in Moshyttan : A study of one of Europe's oldest blast furnaces, using three lakes records in Nora bergslag

Myrstener, Erik January 2013 (has links)
The aim of this study was to assess the environmental effects of Moshyttan, one of the earliest known blast furnaces in Europe (ca. 11th century). The study was based on the analysis of three lake records in the immediate surroundings of the smelter. Fickeln lies directly downstream and is the main recipient of waterborne pollution. Mosjökälla lies directly upstream and served as the main water reservoir for the water-powered bellows. Kramptjärnen lies 1 km to the NW in a separate catchment and acts as a reference. The data includes 31 elements analyzed by X-ray fluorescence spectroscopy (XRF), organic content inferred from loss on ignition (LOI), biogenic silica (BSi) modeled from Fourier-transform infrared spectroscopy (FT-IRS) for all lakes and diatom counts for Fickeln. Two other studies provided dating of slag from the smelter and pollen- and geochemical data from Fickeln. The results show that the metallurgy and associated activities (e.g. agriculture, forest grazing and charcoal production) led to eutrophication and alkalization in Fickeln. This is indicated by the diatom community that in the background is dominated by benthic genera indicative of oligotrophy and dystrophy (Frustilia, Brachisyra and Eunotia) that during the active smelter phase is replaced by pelagic genera indicative of eutrophy (Aulacoseira and Asterionella). BSi also decreases after smelter establishment, which speculatively could indicate an overall decrease in diatom production. At the same time, a suite of elements commonly associated with iron processing (Fe, Pb and Zn) increase in the sediment.
33

Biogenic Particle Transport in the Gaoping Submarine Canyon off Southwestern Taiwan- Comparison of T6KP and T7KP Sediment Traps

Lin, Yi-Jiun 04 September 2009 (has links)
Submarine canyons are common features on continental margins worldwide. They are important natural conduits for transfer of terrigenous sediments to the deep sea, and thus, preferential pathways for shelf-slope exchange. The purpose of this study is to understand the biogenic particle transport in the seasons according two sediment trap moorings deployed in the Gaoping submarine canyon. The T6KP mooring was deployed in dry season while the T7KP mooring was deployed in wet season. Two typhoons, Kalmaegi and Fung Wong, invaded Taiwan during 16-18 and 26-29 July within the deployment of T7KP. We discussed the influence of rainfall and river discharge on biogenic particle transport based on results of the two sediment traps. The foraminiferal abundance in sediment traps in comparison with plankton tows was discussed regarding the particle transport mechanism of the water column in the Gaoping submarine canyon. The biogenic particle transport was a tide-dominated situation and displayed a periodic variation in dry season. In wet season, fine grain fraction (less than 63 micro meter) was dominant in the particle size and sedimentary condition was flood-dominated. The sedimentary condition was back to the tide-dominated state approximately 15 days after Kalmaegi typhoon (16-18, July). The activities of 210Pb and 234Th in the lower trap of T7KP mooring were an order less than that in T6KP mooring, indicating particles scavenge nuclides of the water column less effectively in wet season than in dry season. The absolute abundances of foraminifera in the canyon revealed that the biogenic particle was influenced by the terrigenous input and was different between dry and wet seasons. Seasonal variations of total flux and relative abundance of living foraminifera were evident in the upper 200 m water column near the Gaoping submarine canyon. Therefore, the seasonal variations of living foraminifera might be reflected on the biogenic particle transport in different seasons in the Gaoping submarine canyon.
34

Mechanism of translational regulation of S-adenosylmethionine decarboxylase mRNA by polyamines and an upstream open reading frame /

Raney, Alexa. January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 96-103).
35

Temporal assessment of volatile organic compounds at a site with high atmospheric variability in the North-West Province / Kerneels Jaars

Jaars, Kerneels January 2012 (has links)
Volatile organic compounds (VOCs) are emitted into the atmosphere from biogenic and anthropogenic sources with atmospheric lifetimes ranging from minutes to months, depending on the specific VOC compound considered. It is estimated that biogenic VOCs (BVOCs) (e.g. isoprenes, terpenes) make up 90% of the global atmospheric VOC budget. However, in highly industrialised regions, anthropogenic VOCs (e.g. benzene, toluene, ethylbenzene and xylene, combined abbreviated as BTEX) might dominate. VOCs have various reversible and irreversible effects on human health. They also have environmental impacts that range from changes in the population of terrestrial and aquatic ecosystems to the extinction of vulnerable species. VOCs are precursors for the formation of ozone (O3) during solar radiation initiated reactions in the presence of NOx. Tropospheric O3 is considered a pollutant, with negative impacts on human health, ecosystems and food security. O3 is also a short-lived greenhouse gas. Through reactions with radical species, VOCs lead to the formation of higher molecular weight organic compounds, which produce carbon monoxide (CO), peroxyacytyl nitrate (PAN) and ultimately secondary organic aerosol (SOA) particles. SOA particles impact directly on air quality and visibility, as well as directly and indirectly on the radiation balance of the earth that contributes to the regulation of climate. Notwithstanding the importance of atmospheric VOCs, limited data is available for VOCs in South Africa. In this study, a comprehensive dataset of BVOC and anthropogenic VOC species was obtained at the Welgegund measurement station in the North West Province, South Africa. Measurements were conducted from 9 February 2011 to 4 February 2012. Samples were collected on Tenax-TA and Carbopack-B adsorption tubes twice a week for two hours during day time and two hours during night time. The first 1.25m of the stainless steel sampling inlet was heated to 120ºC to remove O3 that could lead to sample degradation. Analyses of the sampled adsorption tubes were conducted by thermal desorption, cryofocusing, re-desorption, followed by gas chromatography separation and analysis with a mass selective detector (GC-MS). The results indicated that toluene was the most abundant aromatic hydrocarbon and heptane the most abundant alkane. Benzene is currently the only VOC listed as a criteria pollutant in the South African Air Quality Act with an annual average standard of 1.6ppb. The annual median benzene concentration was 0.13 ppb, while the highest daily benzene concentration measured was 8.7 ppb. No distinct seasonal cycles were identified for anthropogenic VOC species measured, i.e. aromatic hydrocarbons and alkanes. However, air mass history analysis indicated that air masses that passed over the Mpumalanga Highveld, the Vaal Triangle and the Johannesburg-Pretoria conurbation (collectively referred to as Area I) had significantly higher concentrations of these anthropogenic VOCs compared to air masses that passed over the western and eastern Bushveld Igneous Complex, and a region over which air masses typically followed an anti-cyclonic movement pattern (collectively referred to as Area II). Anthropogenic VOC levels in air masses that passed over the regional background (areas with no large point sources) had levels similar to air masses that had passed over Area II. Relatively good interspecies correlations (r > 0.8) between most of the aromatic hydrocarbons in air masses that had passed over Area I, with the exception of benzene, indicated that these species had common sources. Benzene, however, correlated well with CO, indicating that sources associated with incomplete combustion were most likely the origin of benzene in air masses that had passed over Area I. The interspecies concentration ratios for plumes passing over Area I indicated that this source region is relatively close to the Welgegund monitoring station and air masses that passed over this source region were substantially influenced by anthropogenic activities. The concentration ratios for plumes that passed over Area II and the Regional Background indicated that these were aged air masses. Furthermore, the concentration ratios of toluene, ethylbenzene and o,m,p-xylene (TEX) to the total aromatic concentration for air masses that passed over the various source regions showed a greater contribution to the total VOC concentration during periods of higher temperature, i.e. summer. This proved that the evaporation of solvents contributes significantly to VOC levels during the months with higher temperatures. The relative contribution of aromatic hydrocarbons to photochemical O3 formation in air masses that passed over the various source regions indicated the highest contribution was observed for air masses that passed over Area I, with Area II and the Regional Background in the same order of magnitude. The annual temporal variations of the measured BVOCs indicated that 2-methyl-3-buten-2-ol (MBO) and isoprene exhibited distinct seasonal patterns, i.e. higher values in summer and lower values in winter. The monoterpenes (MT) and the sesquiterpenes (SQT) did not follow distinct seasonal patterns. BVOC concentrations correlated relatively well to seasonal variations in temperature, photosynthetically active radiation (PAR), rainfall, relative humidity (RH) and CO2 flux. This proved that biogenic activity is responsible for BVOCs emitted. The most abundant MT was -pinene, while -caryophyllene was the most abundant SQT with annual median concentrations of 0.468 ppb and 0.022 ppb, respectively. Pollution roses for isoprene showed a dominance of sources from the north-west to the north-east, as well as the south-east. These directions correlated to areas where pockets of the savannah biome are located. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013
36

Temporal assessment of volatile organic compounds at a site with high atmospheric variability in the North-West Province / Kerneels Jaars

Jaars, Kerneels January 2012 (has links)
Volatile organic compounds (VOCs) are emitted into the atmosphere from biogenic and anthropogenic sources with atmospheric lifetimes ranging from minutes to months, depending on the specific VOC compound considered. It is estimated that biogenic VOCs (BVOCs) (e.g. isoprenes, terpenes) make up 90% of the global atmospheric VOC budget. However, in highly industrialised regions, anthropogenic VOCs (e.g. benzene, toluene, ethylbenzene and xylene, combined abbreviated as BTEX) might dominate. VOCs have various reversible and irreversible effects on human health. They also have environmental impacts that range from changes in the population of terrestrial and aquatic ecosystems to the extinction of vulnerable species. VOCs are precursors for the formation of ozone (O3) during solar radiation initiated reactions in the presence of NOx. Tropospheric O3 is considered a pollutant, with negative impacts on human health, ecosystems and food security. O3 is also a short-lived greenhouse gas. Through reactions with radical species, VOCs lead to the formation of higher molecular weight organic compounds, which produce carbon monoxide (CO), peroxyacytyl nitrate (PAN) and ultimately secondary organic aerosol (SOA) particles. SOA particles impact directly on air quality and visibility, as well as directly and indirectly on the radiation balance of the earth that contributes to the regulation of climate. Notwithstanding the importance of atmospheric VOCs, limited data is available for VOCs in South Africa. In this study, a comprehensive dataset of BVOC and anthropogenic VOC species was obtained at the Welgegund measurement station in the North West Province, South Africa. Measurements were conducted from 9 February 2011 to 4 February 2012. Samples were collected on Tenax-TA and Carbopack-B adsorption tubes twice a week for two hours during day time and two hours during night time. The first 1.25m of the stainless steel sampling inlet was heated to 120ºC to remove O3 that could lead to sample degradation. Analyses of the sampled adsorption tubes were conducted by thermal desorption, cryofocusing, re-desorption, followed by gas chromatography separation and analysis with a mass selective detector (GC-MS). The results indicated that toluene was the most abundant aromatic hydrocarbon and heptane the most abundant alkane. Benzene is currently the only VOC listed as a criteria pollutant in the South African Air Quality Act with an annual average standard of 1.6ppb. The annual median benzene concentration was 0.13 ppb, while the highest daily benzene concentration measured was 8.7 ppb. No distinct seasonal cycles were identified for anthropogenic VOC species measured, i.e. aromatic hydrocarbons and alkanes. However, air mass history analysis indicated that air masses that passed over the Mpumalanga Highveld, the Vaal Triangle and the Johannesburg-Pretoria conurbation (collectively referred to as Area I) had significantly higher concentrations of these anthropogenic VOCs compared to air masses that passed over the western and eastern Bushveld Igneous Complex, and a region over which air masses typically followed an anti-cyclonic movement pattern (collectively referred to as Area II). Anthropogenic VOC levels in air masses that passed over the regional background (areas with no large point sources) had levels similar to air masses that had passed over Area II. Relatively good interspecies correlations (r > 0.8) between most of the aromatic hydrocarbons in air masses that had passed over Area I, with the exception of benzene, indicated that these species had common sources. Benzene, however, correlated well with CO, indicating that sources associated with incomplete combustion were most likely the origin of benzene in air masses that had passed over Area I. The interspecies concentration ratios for plumes passing over Area I indicated that this source region is relatively close to the Welgegund monitoring station and air masses that passed over this source region were substantially influenced by anthropogenic activities. The concentration ratios for plumes that passed over Area II and the Regional Background indicated that these were aged air masses. Furthermore, the concentration ratios of toluene, ethylbenzene and o,m,p-xylene (TEX) to the total aromatic concentration for air masses that passed over the various source regions showed a greater contribution to the total VOC concentration during periods of higher temperature, i.e. summer. This proved that the evaporation of solvents contributes significantly to VOC levels during the months with higher temperatures. The relative contribution of aromatic hydrocarbons to photochemical O3 formation in air masses that passed over the various source regions indicated the highest contribution was observed for air masses that passed over Area I, with Area II and the Regional Background in the same order of magnitude. The annual temporal variations of the measured BVOCs indicated that 2-methyl-3-buten-2-ol (MBO) and isoprene exhibited distinct seasonal patterns, i.e. higher values in summer and lower values in winter. The monoterpenes (MT) and the sesquiterpenes (SQT) did not follow distinct seasonal patterns. BVOC concentrations correlated relatively well to seasonal variations in temperature, photosynthetically active radiation (PAR), rainfall, relative humidity (RH) and CO2 flux. This proved that biogenic activity is responsible for BVOCs emitted. The most abundant MT was -pinene, while -caryophyllene was the most abundant SQT with annual median concentrations of 0.468 ppb and 0.022 ppb, respectively. Pollution roses for isoprene showed a dominance of sources from the north-west to the north-east, as well as the south-east. These directions correlated to areas where pockets of the savannah biome are located. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013
37

Predicting Life Expectancy of Concrete Septic Tanks Exposed to Sulphate and Biogenic Sulphuric Acid Attack

Hasan, Md Saeed, mdsaeed.hasan@rmit.edu.au January 2009 (has links)
The prediction of the expected long-term performance of concrete exposed to sewage and similar materials can be difficult as it is affected by a large number of parameters. In addition, the deterioration process in concrete is generally slow. The focus of the study was to ascertain the life expectancy of concrete septic tanks located in rural Victoria. In developing the accelerated test method, ASTM C 192, ASTM C 452, ASTM C 1293 and ASTM C 109 standard procedures were adopted wherever possible. From the analysis of mass change data after 350 days, it was found that the mass change rate for concrete in sulphate solutions increases with the increase of concentration of Na2SO4 solution. The weights of the samples in Na2SO4 solution increased with time, whereas the control specimens lost weight as a result of heating cycles. The probable reason for weight increase in Na2SO4 solution was hypothesized as the formation of gypsum (CaSO4.2H2O) and ettringite (3CaO.Al2O.3CaSO4.32H2O), which is confirmed from microstructural analysis. The rate of weight gain was higher at the beginning and reduced with time. The stronger the concentration of Na2SO4 the stronger was the weight gain or expansion of mass. All the samples in sulphate solutions attained their maximum weight at around 250 days. For the specimens in sulphuric acid solutions weight loss was observed to be higher for higher concentrations. The lower the pH of the acidic solutions, the larger was the weight loss. The weight loss of specimens in acidic solutions exceeded the control specimen after 250 days. The reason for the loss of weight of the samples in sulphuric acid may be the decalcification of C-S-H gel within the concrete, and as a consequence the loss of cementitious structure. Comparison of the corrosion of concrete and also microstructural examination of field samples confirmed that the deterioration mechanism is similar to that observed in the laboratory. The accelerated testing adopted here offers a realistic method of predicting the deterioration of septic tanks under biogenic sulphuric acid corrosion. Two equations have been proposed to predict deterioration due to sulphate attack and sulphuric acid attack as mass loss (or gain) with time.
38

Are C. elegans receptors useful targets for drug discovery : identification of genes encoding seven potential biogenic amine receptors in the parasitic nematode Brugia malayi and pharmacological comparison of tyramine receptor homologues from Caenorhabditis elegans (TYRA-2) and B. malayi (Bm4) /

Smith, Katherine Ann. January 2007 (has links)
Dissertation (Ph.D.)--University of Toledo, 2007. / Typescript. "Submitted as partial fulfillment of the requirements for The Doctor of Philosophy iin Biology." Bibliography: leaves 96-105.
39

InvestigaÃÃo do Efeito Antidepressivo da Riparina III: AlteraÃÃes Comportamentais, NeuroquÃmicas e AvaliaÃÃo do Estresse Oxidativo / Investigation of Antidepressant Effect of Riparin III: Behavioral and Neurochemical Alterations and Evaluation of Oxidative Stress

Carla Thiciane Vasconcelos de Melo 27 June 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A depressÃo à uma doenÃa recorrente e incapacitante cujo tratamento està relacionado com modulaÃÃes nos sistemas monoaminÃrgicos em diversas Ãreas cerebrais. A riparina III (ripIII), isolada do fruto verde de Aniba riparia, apresentou, em estudos prÃvios, efeito antidepressivo. Dessa forma, objetivando investigar o potencial antidepressivo da ripIII, foram realizados testes comportamentais como o nado forÃado (TNF), suspensÃo da cauda (TSC), hipotermia induzida por apomorfina e campo aberto. Para avaliar o envolvimento das monoaminas, os animais foram prÃ-tratados com antagonistas especÃficos para receptores 5-HT1A, 5-HT2A/2C e 5-HT3 de serotonina (5-HT), D1 e D2 de dopamina (DA) e a1 e a2 de noradrenalina (NA) no TNF. AlÃm disso, os animais prÃ-tratados com ripIII e submetidos ou nÃo ao TNF tiveram as Ãreas cerebrais hipocampo, corpo estriado e cÃrtex prÃ-frontal retiradas para detecÃÃo dos nÃveis de monoaminas ou para realizaÃÃo dos experimentos de estresse oxidativo, investigando a atividade enzimÃtica da catalase e superÃxido dismutase, quantificando os nÃveis de glutationa reduzida (GSH) e nitrito/nitrato, alÃm do grau de lipoperoxidaÃÃo. A ripIII foi administrada agudamente, por via oral, na dose de 50 mg/kg, em todos os testes. Os resultados mostraram que a ripIII apresentou efeito antidepressivo nos modelos TNF e TSC sugerindo ser especÃfico, uma vez que os animais nÃo apresentaram alteraÃÃes na atividade locomotora no campo aberto. AlÃm disso, no TNF, os antagonistas sulpirida (D2), prazosina (a1), ioimbina (a2), NAN-190 (5-HT1A) e ondansentron (5-HT3) reverteram o tempo de imobilidade da ripIII sugerindo a participaÃÃo desses receptores para o efeito da substÃncia, enquanto nÃo houve alteraÃÃo deste efeito na presenÃa dos antagonistas SCH23390 (D1) e ritanserina (5- HT2A/2C) mostrando o nÃo envolvimento desses receptores no efeito da droga. A ripIII nÃo foi capaz de reverter a hipotermia induzida por apomorfina, que na dose utilizada, induz hipotermia por modular receptores b-adrenÃrgicos, sugerindo que o efeito da ripIII nÃo està relacionado com esses receptores. A ripIII apÃs o TNF, em corpo estriado e cÃrtex prÃfrontal, aumentou os nÃveis de DA, 5-HT e NA, diminuiu os metabÃlitos DOPAC, HVA, 5- HIAA e as taxas metabÃlicas e, no hipocampo, aumentou 5-HT e NA alÃm do metabÃlito 5- HIAA, mas manteve as taxas metabÃlicas. A administraÃÃode ripIII, antes do TNF, reverteu o aumento nos nÃveis de peroxidaÃÃo lipÃdica e nitrito-nitrato, reduziu a atividade da catalase mas aumentou os nÃveis de GSH em hipocampo, corpo estriado e cÃrtex prÃfrontal. Esses parÃmetros nÃo foram alterados nos animais nÃo submetidos ao estresse. Em conclusÃo, o estudo sugere uma aÃÃo moduladora, exercida por ripIII, sobre o funcionamento dos sistemas noradrenÃrgico, dopaminÃrgico e serotonÃrgico, em nÃvel central, como mecanismo para o efeito antidepressivo no TNF, bem como a participaÃÃo de propriedades antioxidantes diretas ou indiretas dessa droga, atravÃs da capacidade de modificar a resposta ao estresse oxidativo neuronal. / Depression is a disabling and recurrent disease whose treatment is related to modulations in monoaminergic systems in several brain areas. Riparin III (ripIII), isolated from unripe fruit of Aniba riparia, has shown previously antidepressant-like effects. Thus, in order to investigate the antidepressant effect of ripIII, behavioral experiments were performed, as the forced swim (FST), tail suspension (TST), apomorphine-induced hypothermia and open field tests. To assess the involvement of monoaminergic system, animals were pretreated with specific antagonists to 5-HT1A-, 5-HT2A/2C-, and 5-HT3-serotonin (5-HT) receptors, to D1- and D2-dopamine (DA) receptors and to 1- and 2-noradrenaline (NA) receptors in FST. Further, animals pretreated with ripIII and submitted or not to the FST had their brain areas such as hippocampus, striatum and prefrontal cortex removed for detection of monoamine levels or to carry out the experiments of oxidative stress, in which, it was investigated enzymatic activities of catalase and superoxide dismutase, measured the levels of reduced glutathione (GSH) and nitrite/nitrate, and lipid peroxidation degree. RipIII was acutely administered orally at a dose of 50 mg/kg in all tests. The results showed that ripIII presented antidepressant effect on the FST and TST suggesting that this effect is specific, since the animals showed no changes in locomotor activity in open field test. In the evaluation of monoaminergic systems, the results showed that the antagonists sulpiride (D2), prazosin (1), yohimbine (2), NAN-190 (5-HT1A) and ondansentron (5-HT3) reversed the immobility time of ripIII on the FST suggesting the involvement of these receptors, while no change of this effect in the presence of the antagonists SCH23390 (D1) and ritanserin (5-HT2A/2C) was observed, suggesting non-participation of these receptors in the drug effect. RipIII was unable to reverse the hypothermia induced by apomorphine that at the dose used, modulates -adrenergic receptors inducing hypothermia, suggesting that the effect of ripIII is not related to these receptors. RipIII, after FST, in the striatum and prefrontal cortex, increased levels of DA, 5-HT and NA, decreased DOPAC, HVA, 5-HIAA metabolites and decreased metabolic rates, and in the hippocampus, increased 5-HT and NA and 5-HIAA metabolite, but maintained metabolic rates. The prior administration of ripIII before the forced swimming, reversed the increased levels of lipid peroxidation and nitrite-nitrate, reduced the activity of catalase but increased levels of GSH in hippocampus, striatum and prefrontal cortex. These parameters were not altered in animals not exposed to stress. In conclusion, the study suggests a modulating action exerted by ripIII on the functioning of the noradrenergic, dopaminergic and serotonergic levels in the brain, as a mechanism for the antidepressant effect in the FST, as well as the participation of direct or indirect antioxidant properties of this drug through the ability to modify the neuronal response to oxidative stress
40

Ověření použitelnosti biogenních pojiv při odlévání odlitků z LLG / Test the applicability of biogenic binders during casting of gray cast iron

Fiala, Vlastimil January 2017 (has links)
The thesis deals with verification of applicability of biogenic binders during casting of gray cast iron. Applicability of these binders for making moulds as well as cores was verificated. The introduction describes strength of cured mixture with biogenic binder including influence of additives and refractory coating. The main part describes process of manufacturing of castings being poured into the biogenic binder bonded moulds. Pouring castings with cores bonded with the same binder is described as well. The last part deals with assessment of the given tests. The thesis comprises photodocumentation of poured samples.

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