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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

Analýza vlivu procesu ochlazování na kvalitu proteického gelu / Analysis of influence of cooling process on quality of proteic gel

Semotam, Zbyněk January 2009 (has links)
This diploma thesis deals to possibilities lead chilling process with material loss of product and divine to possibilities lead texture final product with chilling process. This work will be base of project for realization chilling tunnel to flow line of proteinic gel.
32

Aerodynamická interakce dvou vozidel / Aerodynamic interaction of two vehicles

Tárnok, Gábor January 2011 (has links)
The master's thesis deals with the aerodynamic interaction od two vehicles, modelling in CFD software, how the vehicle behaves in leeward.
33

Aerodynamická optimalizace monopostu formule SAE / Formula SAE aerodynamic optimization

Fryšták, Lukáš January 2016 (has links)
Tato práce se zabývá měřením aerodynamických charakteristik modelu závodního vozu Formula SAE v aerodynamickém tunelu, v měřítku 1:4. V první části je představen projekt Formula SAE a popsána role aerodynamiky v rámci této soutěže. Následuje přehled teoretického pozadí, které je relevantní k provedenému experimentu. Ve druhé části práce je popsán samotný experiment a prezentovány jeho výsledky. Součástí je návrh, výroba a kalibrace šestikomponentní tenzometrické váhy pro měření aerodynamického zatížení. Testy v aerodynamickém tunelu byly provedeny ve čtyřech konfiguracích, aby bylo možné určit vliv přítlačných křídel a podlahy s difuzorem na výsledné aerodynamické charakteristiky vozu.
34

Testicular apoptotic activity in two bio-sentinel fish species inhabiting an aquatic ecosystem in an area where continual DDT spraying occurs : utility of immunohistochemical assays

Patrick, Sean Mark 08 July 2009 (has links)
Endocrine disrupting chemicals (EDCs) such as DDT have the ability to disrupt hormonally controlled processes, such as spermatogenesis, which is the maturation of germ cells into spermatozoa. During normal spermatogenesis, germ cell apoptosis can occur, but the degree of apoptosis within the testis could possibly be affected by exposure to EDCs. In 2004, a pilot study on the reproductive health of two freshwater fish species, Oreochromis mossambicus and Clarias gariepinus, from three impoundments in the Luvuvhu River, found concerning levels of DDT and its metabolites in both species from the Nandoni Dam, and in O. mossambicus from the Xikundu Weir. This was not surprising as a large part of the Luvuvhu River catchment is located within an area where ongoing DDT-spraying occurs for vector control purposes. Hence, in 2006, a larger WRC-funded project began to further investigate the findings from the pilot study. A subsidiary study, spanning two seasons, was initiated to investigate testicular apoptosis in fish from the polluted systems, the Nandoni Dam (ND) and the Xikundu Weir (XW), as well as a reference site, the Albasini Dam (AD), utilizing caspase-3 and TUNEL immunoexpression as apoptotic markers. In addition, three fixatives, Bouin’s Fluid (BF), Neutrally Buffered Formalin (NBF) and Paraformaldehyde (PFA), were used to determine which would be the optimal fixative for both histological and immunohistochemical assessments. Sampling occurred during season 1, the low-flow season (October 2007), during DDT spraying of the surrounding area, and season 2, the high–flow season (February 2008), two months after the DDT-spraying was completed. The testes of O. mossambicus (n = 19 season 1, n = 25 season 2) and C. gariepinus (n = 19 season 1, n = 20 season 2) were fixed in the above-mentioned fixatives, embedded in paraffin wax, prepared for immunohistochemistry, and exposed to caspase-3 antibodies and TUNEL antibodies individually. The results indicated that the residues of p,p´-DDT - DDD and - DDE were found in the fat samples of both O. mossambicus and C. gariepinus, in AD, ND and XW. Testicular apoptotic assessment using the caspase-3 assay clearly labeled spermatocytes in the process of cellular death in both seasons, in all three fixatives. When comparing the two assays, a significant difference is found between the caspase-3 and TUNEL positive cells. The results further show that, when comparing the three sampling sites, the highest amount of positive cells are found at the XW. The decrease observed in season two, in both the caspase-3 and TUNEL assay may possibly be linked to the stage of spermatogenesis, coinciding with hormonal changes associated with the different sampling seasons (i.e. breeding and non-breeding seasons). The levels of DDT found in the fat tissue, could not be correlated to an up-regulation in apoptotic cells. The results The results indicated that the choice of fixative, could affect the identification of the amount of positive cells. The utility of the caspase-3 and TUNEL assays, in conjunction with all three fixatives, proves a successful tool in assessing and quantifying modulated testicular apoptosis, creating greater research potential in the assessment of the effects of aquatic pollution. Copyright / Dissertation (MSc)--University of Pretoria, 2008. / Physiology / unrestricted
35

Gravimetrický projev deformačních zón v okolí podzemních dutin / Gravity response of deformation zones around subsurface cavities

Šifnerová, Kristýna January 2010 (has links)
The main purpose of this diploma thesis was to determine whether the deformation zone, which arises above intact mining workings in soils, has a measurable gravity effect and influences the interpretation of gravity measurements. The railway tunnel in Březno u Chomutova has been chosen as a test site. We have progressed so that the geotechnical model of the geological environment above the tunnel was calculated first. The model was constructed on the base of two core wells, which were drilled near the tunnel especially for this purpose. The geotechnical model of deformation zone was converted into a density model and its gravity response was calculated. This model was compared with the gravity effect of the tunnel in rock environment without any deformation zone. The difference between effects of these two models gives the gravity response of the deformation zone. We found out that the gravity effect of the deformation zone is insignificant and does not affect the gravity interpretation in the environment of stiff tertiary clays, where the Březno tunnel is excavated. We compared the results of our modeling with the field gravimetric measurements results above the tunnel in Březno. The measurement was realized on three parallel profiles, which reach the tunnel in various depths. The results of...
36

Uticaj oblika i vrste aerodinamičke opreme privrednih motornih vozila na otpor vazduha / The impact of shape and type of aerodynamics equpment on the commercil vehicle's drag force reduction

Galamboš Stjepan 23 October 2020 (has links)
<p>Usavršavanje aerodinamike privrednim motornih vozila putem optimizacije aerodinamičkih dodataka u svrhu postizanja boljih aerodinamičkih performansi u vidu umanjenja sile otpora vazduha. Prostiranje vazdušne struje oko modela je unapređeno optimizacionim dodacima što se sve ogleda u smanjenoj potrošnji goriva privrednog motornog vozila. Osim virtuelnih simulacija računarske dinamike fluida, u radu je prikazana validacija rezultata putem eksperimentalnog merenja u vazdušnom tunelu.</p> / <p>The improvement of commercial motor vehicle&#39;s aerodynamics through optimization process of aerodynamic equpments in order to achieve better aerodynamic performance in the form of drag force reduction. The expansion of the air flow around the model is enhanced by optimization accessories, which is all reflected in the reduced of fuel consumption of the commercial motor vehicle. In addition to virtual simulations of computational fluid dynamics, the paper presents the validation of results by experimental measurement in the wind tunnel.</p>
37

Germ Cell Responses to Doxorubicin Exposure in Vitro

Habas, Khaled S.A., Anderson, Diana, Brinkworth, Martin H. 24 November 2016 (has links)
Yes / Anthracyclines such as doxorubicin (Dox), widely used to treat various types of tumours, may result in induced testicular toxicity and oxidative stress. The present investigation was designed to determine whether exposure of isolated and purified mouse germ cells to Dox induces DNA damage in the form of strand breaks (presumably) resulting in apoptosis and to investigate the relative sensitivity of specific cell types. DNA damage was assessed using the Comet assay and the presence of apoptosis was determined by TUNEL assay. Isolated mouse germ cells were treated with different concentrations (0.05, 0.5 and 1 mM, respectively) of Dox, and fixed 1 h after treatment. The incidences of both DNA damage shown by single cell gel-electrophoresis and of apoptosis increased significantly in each specific cell type in a concentration-dependent manner. The DNA damage and apoptosis incidences gradually increased with concentration from 0.05 to 1 mM with Dox. Our results indicate that apoptosis plays a vital role in the induction of germ cell phase-specific toxicity caused by Dox with pre-meiotically and meiotically dividing spermatogonia and spermatocytes respectively as highly susceptible target cells. / Higher Education Funding Council for England (HEFCE)
38

In vitro studies on genotoxicity and gene expression in spermatogenic cells: mechanisms and assay development

Habas, Khaled S.A. January 2015 (has links)
Spermatogenesis is a complex process of male germ cell development from diploid spermatogonia to haploid fertile spermatozoa. Apoptosis plays a vital role in limiting cell numbers and eliminating defective germ cells. This requires novel gene products, and precise and well-coordinated programmes of gene expression. It is therefore possible that a disruption of transcription factor function would significantly impact germ cell development. The present work was undertaken to use Staput separation followed by culture of purified germ cells of rodent testis since mammalian spermatogenesis cannot yet be recreated in vitro. Specificity of separation was assessed using immunocytochemistry to identify spermatogonia, spermatocytes and spermatids. The genotoxins H2O2, doxorubicin, N-ethyl-N-nitrosourea, N-methyl-N-nitrosourea, 6-mercaptopurine, 5-bromodeoxyuridine, methyl methanesulphonate and ethyl methanesulphonate were investigated. Cells were cultured and treated with different concentrations for each agent. DNA damage and apoptosis were measured by Comet and TUNEL assay respectively. Up-regulation of expression of the transcription factors Tbpl1, FHL5 and Gtf2a1l that are important post-meiotically, were examined using RT- PCR and qPCR. Protein production was evaluated using Western blotting. Tbpl1, FHL5 and Gtf2a1l were cloned in-frame into the inducible expression vector pET/100-TOPO. The recombinant clones were induced and successful expression of the proteins in E. coli was confirmed by SDS-PAGE and Western blotting. The recombinant clones obtained were used to demonstrate genotoxin induced impairment of gene expression. Thus, Staput-isolated rodent testicular germ cells seem to be a suitable model to study genotoxicity in vitro yielding result comparable to those reported in vivo. Furthermore, the work shows that genotoxins can impair gene expression.
39

Realizace tunelu Radejčín - vybrané části stavebně technologického projektu / Realization of tunnel Radejčín - the chosen parts of construction technological project

Hájek, Libor January 2012 (has links)
The issue of the thesis is a construction of the Radejčín highway tunnel. Project contains all of the stages of construction. The total budget and time schedule were made for complete structure. The technological instruction was made for secondary lining of the tunnel. There is also a plan of security instruction, the list of risks on construction site, suggestion of fixed job contract, the plan of controlls and exams for making invert and upper vault of secondary lining. Another part is the project of construction site with three different drawing of construction sites and text part. The list of machines and devices is for the complete construction. It was added also a chosen construction details and evaluation of geotechnical monitoring.
40

Avaliação do alcance de retalho pediculado de omento maior através de túnel subcutâneo para ossos longos em cães / Evaluation of to reach of greater omentum pedicle flap througt a subcutaneous tunnel to long bones in dogs

Ito, Kelly Cristiane 12 December 2008 (has links)
O omento maior tem sido utilizado com grande eficácia na medicina e em cirurgias torácicas, urogenitais, neurológicas, vasculares e respiratórias por sua natureza única, versátil e suas propriedades de imunidade, drenagem, adesão, vascularização e hemostasia bem conhecidas. Tem sido aplicado em humanos, como uma importante fonte de vascularização para áreas distantes, como flap pediculado ou livre, dentre elas, tórax, cabeça, pescoço e porções proximais de extremidades. As pesquisas com flap pediculado de omento maior, na cirurgia veterinária como indutor angiogênico e imunogênico são poucas, entretanto, suas propriedades de adesão e drenagem são conhecidas e utilizadas em procedimentos cirúrgicos com excelentes resultados. O objetivo desta pesquisa foi criar retalho pediculado de omento maior, mensurando o comprimento durante as etapas de criação e avaliando a possibilidade de alcance para ossos longos (fêmur, tíbia, úmero e rádio e ulna) através de túnel subcutâneo. Foram utilizados 30 cadáveres de cães frescos com 10 a 30 quilos de massa corpórea, sem discriminação de idade, sexo ou raça. Os resultados foram satisfatórios e 100% dos animais alcançaram a metáfise distal dos ossos avaliados. A média de comprimento do omento em camada dupla, dos 30 animais avaliados foi de 30,87 cm, da camada simples de 54,37 cm e do flap em L 92,7 cm. Com a extensão máxima do omento foi possível alcançar as metáfises distais de todos os ossos propostos (fêmur, tíbia/fíbula, úmero e rádio/ulna), com comprimento médio excedente de 29,87 cm para fêmur, 20,73 cm para tíbia/fíbula, 25,13 cm para úmero e 16,27 cm para rádio/ulna As variáveis peso flap em L avaliadas estatisticamente apresentaram correlação positiva moderada nos grupos apresentados. Concluiu-se que em cães é possível levar o flap pediculado de omento maior através de túnel subcutâneo para metáfise distal de ossos longos sem tensão e que quanto maior o peso do animal, maior o comprimento do flap em L dos animais avaliados em cada grupo. / The greater omentum has been successfully used in human medicine in different surgical approaches such as thoracic, urogenital, neurological, vascular, and respiratory. The high usefulness of omentum is due to its singular nature and versatility, as well as its known different properties such as immunologic, drainage, adhesion, angiogenic and haemostatic. It has been used in human medicine such as a pediculated or free flap as an important vascular inductor for different areas. Among the sites that it has been used to increase blood flow by its angiogenic properties, little the thorax, head and neck, and proximal and distal extremities may be sited. Research on immunogenic and angiogenics inductor properties of the flap in Veterinary Medicine have been made, however, its adhesive and draining properties are well known and have been used with excellent results in surgery. An experimental study to obtain a pediculated flap of greater omentum and conduct it as far as possible through a subcutaneous tunnel in order to reach long bones (femur, tibia, umero, radius and ulna). Was designed during the experiment, the obtained different flaps were measured and the possibility of reaching proximal to distal long bone sites was checked. For the experiment 30 fresh body (10 to 30 kg of corporal weight) from dead dogs without predilection to age, or sex were used. Animals of all breeds were included except condrosdistrophics breeds. In addition, dogs with signs of abdominal surgery, abdominal adherences, or other anatomic dysfunctions of the greater omentum were excluded from the experiment. The results were satisfactor and in 100% of the cases the flap reached the distal half of the evaluated bones. The averages of the different flap lengths were: 30.87 cm when double layer was used; 54.37 cm in simple layer; and 92.7 cm when the flap was made in an L shape. With the largest extension of the omentum, it was possible to reach the distal metaphises of all studied bones (femur, tibia/fibula, humerus, and radius/ulna). The exceeding length average was 29.87 cm for the femur, 20.73 cm for the tibia/fibula, 25.13 cm for the humerus, and 16.27 cm for the radius/ulna. The variation body-weight-flap variety statistically evaluated showed moderate positive correlation on the presented groups. In conclusion, the omentum pediclulated flap may be passed through the subcutaneous tunnel until the distal metaphisis of the long bones of dogs without tension. Animals with carger bodyl weight have the largest length of the L- shaped flap.

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