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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.
81

Análise da expressão e de mecanismos de regulação de genes envolvidos na transição epitélio mesênquima em carcinoma renal de células claras / Epithelial to mesenchymal transition related genes are differentially expressed in clear cell renal cell carcinoma

Conceição, André Luis Giacometti [UNESP] 16 February 2016 (has links)
Submitted by ANDRÉ LUIS GIACOMETTI CONCEIÇÃO null (andre4487@gmail.com) on 2016-03-08T12:40:30Z No. of bitstreams: 1 Arquivo_Completo_-_Tese_Doutorado_-_André_Luis_Giacometti_Conceição.pdf: 1296182 bytes, checksum: 29c1b4fbebefc1b96e79210f433f4d2f (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-03-09T16:44:10Z (GMT) No. of bitstreams: 1 conceicao_alg_dr_sjrp.pdf: 1296182 bytes, checksum: 29c1b4fbebefc1b96e79210f433f4d2f (MD5) / Made available in DSpace on 2016-03-09T16:44:10Z (GMT). No. of bitstreams: 1 conceicao_alg_dr_sjrp.pdf: 1296182 bytes, checksum: 29c1b4fbebefc1b96e79210f433f4d2f (MD5) Previous issue date: 2016-02-16 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O carcinoma renal de células claras (ccRCC) é o mais comum dos subtipos histológicos de carcinoma renal. Este carcinoma é histologicamente caracterizado pela presença de células com citoplasma claro e abundante. O processo inicial de metástase pode ser atribuída à transição epitélio mesênquima (EMT). Neste estudo, buscou-se identificar genes diferencialmente expressos em ccRCC, construindo assim um perfil molecular para este tumor. Nós selecionamos genes descritos na literatura que apresentam relação com EMT, diferenciação e proliferação celular. Analisou-se por PCR quantitativo e imuno-histoquímica a expressão dos genes e suas proteínas, respectivamente, e os possíveis mecanismos epigenético que regulam a sua expressão em amostras de ccRCC e linhagem celular. Os genes OCLN e GAS1 foram encontrados com baixa expressão em ccRCC, e nós sugerimos que o miR-122 e miR- 34a podem regular sua expressão, respectivamente, neste tipo de câncer. Além disso, mostramos, por qPCR e imuno-histoquímica, a alta expressão de SLC2A1 foi significantemente alta em ccRCC. O conjunto de genes identificados neste estudo possibilita a compreensão das bases moleculares e de desenvolvimento do ccRCC. / Clear cell renal cell carcinoma (ccRCC) is the most common histological subtype of kidney cancer. This carcinoma is histologically characterized by the presence of clear and abundant cytoplasm. The initial process of ccRCC metastatic tumor formation can be attributed to epithelial- mesenchymal transition (EMT). In this study, we sought to identify genes differentially expressed in ccRCC and build a molecular profile of this cancer. We selected genes described in the literature to be related to EMT, cellular differentiation and proliferation. We analyzed the gene and protein expression by quantitative PCR and immunohistochemistry, respectively, and examined possible epigenetic mechanisms that regulate their expression in ccRCC samples and cell lines. OCLN and GAS1 genes were under-expressed in ccRCC, and we report that miR-122 and miR- 34a, respectively, may regulate their expression in this cancer. Furthermore, we showed by quantitative PCR (qPCR) and immunohistochemistry that SLC2A1 was significantly over-expressed in ccRCC. The set of genes identified in this study furthers our understanding of the molecular basis and development of ccRCC. / FAPESP: 2012/08853-0
82

Sledování dynamiky prokysávání mléka vybranými mlékařskými kulturami / Evaluation of fermentation activity of chosen pure dairy cultures in milk and cultured milk products

KRAMPL, Pavel January 2008 (has links)
This work deals with dynamics of milk souring after injection with chosen dairy culture in dependence on varying conditions of cultivation and different quality of the cultural medium. The aim of this work is:  Evaluation of the influence milk heat treatment has on the rate of milk souring by chosen clear dairy cultures.  Evaluation of the influence temperature of the milk has on the rate of milk souring by chosen clear dairy cultures.  Evaluation of the influence the quality of the milk has on the rate of milk souring by chosen clear dairy cultures. In the first part of my work there will be described milk as a primary commodity, its technological and microbiology characteristics, division of dairy cultures used in general practice and their application. In the next part of the work there will be described methodology, the way the laboratory research has been made and what commodities have been used. In this part there is also mentioned how the researches was evaluated and in what way the obtained results were processed. The ending part contains description and summary of results of the research and there is hold a discussion and a comparison of the results with other authors.
83

Undersökning av näringsläckage till akvatiska miljöer : Kartläggning av näringsstatusen i vattenmiljön för området kring Byssträsket, Lycksele kommun

Larsson, Simon January 2015 (has links)
During the summer of 2013 the environmental office at Lycksele Municipality received a complaint, regarding algal blooms at the stream outlet between the lakes Kalven and Byssträsket in the southern parts of Lycksele Municipality. No deeper studies were made to ensure what could have caused the bloom. The purpose of this report was to examine if there was a specific source contributing to high levels of nutrients in the stream, mainly focusing on clear-cuts and a small dam by the stream inlet, and if the nutrient status differed along the stream flow. Therefore, suitable sites were picked for examination, following the stream flow between the two lakes, and in a stream not affected by clear-cuts for reference. Water samples were picked at each site, determining the status of the parameters total-nitrogen, total-phosphorus, nitrate, ammonium, pH and conductivity. The result showed quite high levels of total-phosphorus (ranging from 40-50 µg/l) and total-nitrogen (ranging from 350-450 µg/l), but low levels of ammonium and nitrate. The results showed no sign of a nutrient input from a specific location. The conclusion of this study is that the present nutrient levels could be high enough to result in a bloom, though probably dependent on contributing factors, such as warmer weather and lower water levels. An alternative explanation is that the nutrient levels could have been higher 2013, deriving from new clear-cuts, but that these clear-cuts stopped leaching nutrients due to older age. Hence, due to lack of previous studies no exact assumption can be made
84

Neural and Behavioral Mechanisms of Clear Speech

Luque, Jenna Silver 15 November 2017 (has links)
Clear speech is a speaking style that has been shown to improve intelligibility in adverse listening conditions, for various listener and talker populations. Clear-speech phonetic enhancements include a slowed speech rate, expanded vowel space, and expanded pitch range. Although clear-speech phonetic enhancements have been demonstrated across a variety of talkers, only a subset of these changes may be required for listeners to benefit perceptually from clear speech. Furthermore, while current literature has provided some understanding of the phonetic enhancements that are typical of clear speech and the improvements in intelligibility resulting from its use, less is understood regarding how listeners benefit from clear speech. Understanding the mechanisms underlying the effectiveness of clear speech will provide insight into speech processing more generally. To that end, two studies were conducted to investigate the possible mechanisms underlying clear-speech benefits. The first study tests the hypothesis that clear speech reduces the amount of information needed for syllable identification. The amount of information presented to listeners was controlled using a silent-center syllable paradigm, in which various amounts of the center or edge of the syllables were removed. The second study tests the hypothesis that phonetic processing of clear speech requires fewer neuro-cognitive resources than typical, or conversational, speech. An Event Related Potential (ERP) paradigm, focused on the Phonological Mismatch Negativity (PMN) component, was used to compare participants’ neurophysiological responses to conversational- and clear-speech stimuli. Results from the first experiment supported the hypothesis of a clear-speech benefit in partial syllables, although the effect was stronger for some vowels than for others. The second experiment demonstrated differences in the way the brain responds to clear versus conversational speech, for syllables in which only the nucleus varied across stimuli. Match-mismatch differences were found in the MMN and PMN components, while the N600 component was found to respond to style differences.
85

Hexamethylene Diisocyanate Homopolymer and Monomer Exposure Assessment and Characterization at an Automobile Manufacturer in the United States

Sivaraman, Karthik Reguram 30 June 2016 (has links)
A variety of paint products are used for their aesthetic and anti-corrosive properties. Isocyanates are consistently found in automobile paint products, particularly in clear coat polyurethane products. Clear coat is typically sprayed via pressurized air by means of an auto-spray robot. In clear coat repair situations, manual, air-powered spray guns are used, and manual spray Operators administer the clear coat material. The isocyanates are a primary anti-corrosive agent in polyurethane products. The Occupational Safety and Health Administration (OSHA) has not established a Permissible Exposure Limit (PEL). The National Institute for Occupational Safety and Health (NIOSH) and American Conference of Governmental Industrial Hygienists (ACGIH) have set Recommended Exposure Limit (REL) and Threshold Limit Value (TLV), respectively. NIOSH recommends a 0.005 parts per million (ppm), 10-hour Time Weighted Average (TWA), and a ceiling exposure of 0.020 ppm in a 10 minute period. Similarly, ACGIH recommends a 0.005 ppm, 8 hour TWA. Automobile manufacturers use clear coats in a variety of ways. Some may use clear coats with blocked isocyanates, or isocyanates that are completely reacted, and others may use clear coat products that allow isocyanates to be liberated during an application, baking, and curing process. The research objective of this study was to characterize exposure, focusing on a single manufacturer’s use of isocyanate-containing clear coats in their Paint Department. A newly evaluated medium (ISO 17734) using di-n-butylamine as a derivative agent, in a denuder tube, was selected instead of NIOSH methods 5521, 5522, and 5525. The ISO evaluated medium was selected to reduce secondary hazard exposure to toluene in impingers. Second, a medium developed by SKC, Inc., called ISO-CHEK®, was not selected because of the short collection time, sensitivity of the medium after collection, and storage and shipping requirements for analysis. Sampling took place over two days, one day for manual spray operations with 2 personal samples from Operators, and 4 area samples collected, and the second day for auto-sprayer Inspectors with 4 personal samples collected. The samples were then analyzed for hexamethylene diisocyanates (HDI) monomer and homopolymer species. The 0.005 ppm, 10 hour TWA; the 0.020 ppm ceiling limit (10 minutes); and the 0.005 ppm 8-hour TWA TLV were not exceeded on either day of sampling. Neither the area nor the personal samples exceeded the 10 hour TWA, ceiling limit, or TLV. In fact, the results had to be recalculated in to parts per billion (ppb). The average exposure for manual spray Operators was 0.052 ppb for the homopolymer, and 0.024 ppb for the monomer species. For auto-spray Inspectors, the average was 0.053 ppb for the homopolymer component and 0.021 ppb for the monomer species. Though the average isocyanate concentration was similar for both Operators and Inspectors, the averages are still below REL and TLV recommendations. These data provided preliminary information regarding the exposure to isocyanates from clear coat use, and also provide context for future evaluation of isocyanate use at this automobile manufacturer. The low concentration of isocyanates could indicate working ventilation systems, liberation of isocyanate species to non-hazardous forms, or low volatilization of isocyanates from the clear coat.
86

Integrating regulatory and methylome data for the discovery of clear cell Renal Cell Carcinoma (ccRCC) variants

Calvert-Joshua, Tracey January 2015 (has links)
>Magister Scientiae - MSc / Kidney cancers, of which clear cell renal cell carcinoma comprises an estimated 70%, have been placed amongst the top ten most common cancers in both males and females. With a mortality rate that exceeds 40%, kidney cancer is considered the most lethal cancer of the genitourinary system. Despite advances in its treatment, the mortality- and incidence rates across all stages of the disease have continued to climb. Since the release of the Human Genome Project in the early 2000’s, most genetics studies have focused on the protein coding region of the human genome, which accounts for a mere 2% of the entire genome. It has been suggested that diverting our focus to the other 98% of the genome, which was previously dismissed as non-functional “junk DNA”, could possibly contribute significantly to our understanding of the underlying mechanisms of complex diseases.In this study a whole genome sequencing somatic mutation data set from the International Cancer Genome Consortium was used. The non-coding somatic mutations within the promoter, intronic, 5-prime untranslated and 3-prime untranslated regions of clear cell renal cell carcinoma-implicated genes were extracted and submitted to RegulomDB for their functional annotation.As expected, most of the variants were located within the intronic regions and only a small subset of identified variants was predicted to be deleterious. Although the variants all belonged to a selected subset of kidney cancer-associated genes, the genes frequently mutated in the non-coding regions were not the same genes that were frequently mutated in the whole exome studies (where the focus is on the coding sequences). This indicates that with whole genome sequencing studies a new set of genes/variants previously unassociated with the clear cell renal cell carcinoma could be identified. In addition, most of the non-coding somatic variants fell within multiple transcriptions factor binding sites. Since many of these variants were also deleterious (as predicted by RegulomDB), this suggests that mutations in the non-coding regions could contribute to disease due to their role in transcription factor binding site disruptions and their subsequent impact on transcriptional regulation. The substantial overlap between the genes with the most aberrantly methylated variants and the genes with the most transcription factor binding site disruptions signifies a potential link between differential methylation and transcription factor binding site affinities. In contrast to the upregulated DNA methylation generally seen in promoter methylation studies, all of the significant hits in this study were hypomethylated, with the subsequent up-regulation of the genes of interest, suggesting that in the clear cell renal cell carcinoma, aberrant methylation may play a role in activating proto-oncogenes, rather than the silencing of genes. When a cross-analysis was carried out between the gene expression patterns and the transcription factor binding site disruptions, the non-coding somatic variants and differential methylation profiles, the genes affected again showed a clear overlap. Interestingly, most of the variants were not present in the 1000genomes data and thus represent novel mutations, which possibly occurred as a result of genomic instability. However, identifying novel variants are always promising, since they epitomise the possibility of developing pioneering ways to target diseases. The numerous detrimental effects a single non-coding mutation can have on other genomic processes have been demonstrated in this study and therefore validate the inclusion of non-coding regions of the genome in genetic studies in order to study complex multifactorial diseases. / National Research Foundation (NRF) and DAAD
87

Model pro krátkodobou predikci výroby elektrické energie z fotovoltaických zdrojů / Model for short-term forecasting of photovoltaic energy production

Kotlorz, Lukáš January 2017 (has links)
Nowadays, electricity production from photovoltaics power plants is becoming important increasingly. In order to set production to other power plants, it is necessary to predict the generation of electricity from these sources. The thesis is mainly devoted to models for short-term prediction, which is based on weather forecast. The models were designated by beta regression and linear regression with transformed explanatory variable. One part of thesis is devoted to Clear sky model, which is used to estimated the maximum possible production at given hour. 1
88

Enhancing UV-protection of clear coated wood by utilizing reactive UV-absorber and epoxyfunctionalized soybean oil

Olsson, Sara January 2012 (has links)
This work presents the development of a new pretreatment for clear coated wood, that aims to increase the photoprotection of exterior wood products, and at the same time make the system more environmentally friendly. The pretreatment comprises the reactive UV absorber 2-hydroxy-4(2,3-epoxy­propoxy)-benzophenone (HEPBP), which has a primary epoxy group that can be covalently attached to the hydroxyl groups of the wood substrate. This reactant is accompanied by renewable epoxy functionalized soybean oil (ESBO), which contains a secondary epoxy group that also has the ability to react with the substrate and that promotes the compatibility between the two reactants. The ESBO further seems to have the advantage of increasing the flexibility of the pretreated veneers as well as decreasing the amount of water in the cell wall of the wood. The study was performed in two parts where the first part focused solely on the development and performance of the pretreatment, whereas the second part used the knowledge gained from part one to evaluate the pretreatment in combination with an acrylic clear coating. Grafting reactions were performed on thin wood veneers heated in solvent. In the first part the reaction parameters, temperature and reaction time, were varied to study their effects on the final properties of the pretreatments. The veneers where then analyzed using FTIR to determine if grafting was achieved. Results show that grafting was successful for reactions performed at temperatures above 90 °C. For part two, grafting was successful for both the boil- and dip process, indicating that a considerably shorter reaction time can be used. Samples from both part one and two where then exposed to accelerated ageing and the color change was measured to estimate the UV-resistance. The first part showed improved UV-resistance for some of the pretreatments, whereas the second part was more difficult to evaluate due to the top coat, but a slight improvement can be seen for samples using the pretreatment. A positive result for part two is also that the pretreatment do not appear to affect the adhesion between the substrate and the top coat. It is hence concluded that the proposed pretreatment is a possible way of increasing the photostability of exterior wood. / Detta arbete beskriver utvecklandet av en ny förbehandling för klarlackat trä som syftar till att öka UV-beständigheten av träprodukter för utomhusbruk. Arbetet syftar även till att utveckla systemet till att bli miljövänligare än nuvarande liknande produkter på marknaden. Förbehandlingen utnyttjar primära epoxidgrupper hos den reaktiva UV-absorbenten 2-hydroxy-4(2,3-epoxy­propoxy)-bensofenon (HEPBP) för att skapa kovalenta bindningar till hydroxylgrupper hos träet. Den andra komponenten i systemet är förnyelsebar epoxiderad sojaolja (ESBO) innehållande sekundära epoxidgrupper som även dessa kan binda kovalent till träytan, samt gynna kompatibiliteten mellan de två reaktanterna. Oljan verkar dessutom öka flexibiliteten av förbehandlingen, samtidigt som den minskar mängden vatten som tränger in i cellväggen. Studien utfördes i två delar där den första delen fokuserade enbart på att utveckla förbehandlingen, medan den andra delen utnyttjade information från den första delen för att utvärdera funktionen av förbehandlingen i kombination med en akrylatbaserad klarlack. Ympningsreaktionerna utfördes på tunna träfaner i uppvärmd lösning. I första delen studerades hur temperatur- och reaktionstidsförändringar påverkar den slutgiltiga prestationen av förbehandlingen, och FTIR användes då för att verifiera ympningen. Resultaten visar att ympningen var lyckad för reaktioner utförda vid reaktionstemperaturer över 90 °C. För del två ansågs ympningen lyckad för både dopp- och kokreaktionen, vilket tyder på att betydligt kortare reaktionstider skulle kunna användas. Prover från både del ett och två utsattes sedan för accelererad åldring där färgförändringen av proverna mättes för att uppskatta UV-resistensen av behandlingarna. Första delen visade på ökad UV-beständighet för vissa av behandlingarna. Del två var dock svårare att utvärdera till följd av klarlacken, men en liten förbättring kan noteras för prover som är förbehandlade. En positiv notering från del två är även att adhesionen mellan klarlacken och träytan inte verkar ha påverkats av förbehandlingen. Med detta som grund dras slutsatsen att den föreslagna förbehandlingen kan förbättra UV-resistensen av klarlackat trä för utomhusbruk. / QC 20120330
89

Lokalt eller hållbart producerat? : Jämförelse mellan koldioxidutsläpp från två alternativa trävirke för brobygge över Skellefteälven. / Locally or sustainably produced? : Comparison between carbon dioxide emissions from two wood source alternatives for bridge construction over Skellefteälven

Berggren, Sally January 2022 (has links)
Emissions of greenhouse gasses, such as carbon dioxide, have been shown to be strongly connected global warming. In 2020 the European Union adopted the goal of reducing emissions of greenhouse gasses to a net of zero before year 2050. This is essential for keeping the average global temperature rise below 1.5 degrees. A large source of carbon dioxide emissions in Sweden is the forestry sector. The carbon balance in ecosystems is usually disturbed due to clear-cutting, which is the main silvicultural system used in Sweden. Introducing more sustainable silvicultural systems, such as continuous cover forestry, is a measure that authorities advocate. This study aimed to examine emissions of carbon dioxide from two timber sources that may be used for a bridge construction in Skellefteå. The timber would either come from a local clear-cut, transported by truck, or from continuous cover forestry in Lithuania, transported to Sweden by ship. The result is based on literature and calculations on data from previous studies. The results showed effects on carbon balance due to different silvicultural systems are complex, though the alternative with continuous cover forestry seemed to contribute to less emissions, despite the timber not being locally produced. The main factor between the systems, and therefore the different levels of emissions, seems to be highly dependent on how much of the harvested trees that is suitable for timber. However, emissions will also depend on local conditions such as timber storage. Therefore, it is important to take this into account when comparing silvicultural systems.
90

Hydrological Modelling at Road Structures in a Changing Climate and Landuse.

Briel, Annemarie January 2013 (has links)
An increase in the frequency and intensity of storm events is predicted by numerous climate researchers for the north of Europe. Not only this but also landuse change in form of clear-cutting can have an impact on the discharge of rivers and with that on road drainage structures. Extensive societal costs can be the consequences of blockage and underdimensioned structures. Hydrological models are powerful instruments that can be used to assess the future dimension requirements for road drainage structures especially in specifically vulnerable areas. In this thesis the hydrological model MIKE SHE was set up to study the discharge and water level at two pipe bridges and one culvert within the catchment of the river Hakerud in Västra Götaland, Sweden. Three scenarios were considered including a changing climate until 2050 and 2100 and a clear-cut scenario aiming to find out if the current design is sufficient for the future. This model can be used as an example model set-up for similar studies taking the recommendations of the experience gained in this thesis into consideration. For the Swedish Transport Administration further studies on this basis can contribute to decision making on the dimensioning of road drainage structures in the future to ensure a safe and robust infrastructural system.

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