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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.
1

Multivariate analyses of proteomic and metabolomic patterns in brain tumors / Multivariat analys av proteomik- och metabolomikmönster i hjärntumörer

Wibom, Carl January 2009 (has links)
Glioblastoma multiforme (GBM) is the most common primary brain tumor. Given the current standard of care, the prognosis for patients diagnosed with this disease is still poor. There consequently exists a need to improve current treatments, as well as to develop new ones. Many obstacles however need to be overcome to facilitate this effort and one of these involves the development of improved methods to monitor treatment effects. At present, the effects of treatment are typically assessed by radiological means several months after its initiation, which is unsatisfactory for a fast growing tumor like GBM. It is however likely that treatment effects can be detected on a molecular level long before radiological response, especially considering many of the targeted therapies that are currently being developed. Biomarkers for treatment efficacy may be of great importance in the future individualization of brain tumor treatment. The work presented herein was primarily focused on detecting early effects of GBM treatment. To this end, we designed experiments in the BT4C rat glioma model in which we studied effects of both conventional radiotherapy and an experimental angiogenesis inhibitor, vandetanib. Brain tissue samples were analyzed using a high throughput mass spectrometry (MS) based screening, known as Surface Enhanced Laser Desorption/Ionization - Time of Flight - Mass Spectrometry (SELDI-TOF-MS). The vast amounts of data generated were subsequently analyzed by established multivariate statistical methods, such as Principal Component Analysis (PCA), Partial Least Squares (PLS), and Orthogonal Partial Least Squares (OPLS), developed for analysis of large and complex datasets. In the radiotherapy study we detected a protein spectrum pattern clearly related to tumor progression. We notably observed how this progression pattern was hampered by radiotherapy. The vandetanib study also revealed significant alterations of protein expression following treatment of different durations, both in tumor tissue and in normal brain contralateral to the tumor. In an effort to further elucidate the pathophysiology of GBM, particularly in relation to treatment, we collected extracellular fluid (ECF) samples from 11 patients diagnosed with inoperable GBM. The samples were collected by means of stereotactic microdialysis, both from within the contrast enhancing tumor and the brain adjacent to tumor (BAT). Samples were collected longitudinally from each patient in a time span of up to two weeks, during which the patient received the first five fractions of radiotherapy. The ECF samples were then analyzed by Gas Chromatography Mass Spectrometry (GC-MS) to screen them with respect to concentrations of low molecular weight compounds (metabolites). Suitable multivariate analysis strategies enabled us to extract patterns of varying metabolite concentrations distinguishing between samples collected at different locations in the brain as well as between samples collected at different time points in relation to treatment. In a separate study, we also applied SELDI-TOF-MS and multivariate statistical methods to unravel possible differences in protein spectra between invasive and non-invasive WHO grade I meningiomas. This type of tumor can usually be cured by surgical resection however sometimes it grows invasively into the bone, ultimately causing clinical problems. This study revealed the possibility to differentiate between invasive and non-invasive benign meningioma based on the expression pattern of a few proteins. Our approach, which includes sample analysis and data handling, is applicable to a wide range of screening studies. In this work we demonstrated that the combination of MS screening and multivariate analyses is a powerful tool in the search for patterns related to treatment effects and diagnostics in brain tumors.
2

Sequence Stratigraphy and Paleoecology of the Late Mississippian Little Stone Gap Member in the Appalachians of West Virginia

Oyewumi, Adeola Adedoyin 12 June 2012 (has links)
The upper Mississippian (Chesterian) Little Stone Gap Member of the Hinton Formation in southern West Virginia was evaluated for its lithofacies and faunal composition. Petrographic and multivariate analyses were used to provide a better understanding of the ecological factors and sequence stratigraphic processes that controlled taxa ordinations and spatiotemporal shifts in facies. Six carbonate and three siliciclastic facies occur within the study interval and these facies stack into two distinct parasequence types. Siliciclastic facies were deposited in continental, low-energy lagoonal and marginal marine environments. Carbonate facies record variable energy conditions in lagoonal, shoal, shoal flank and open marine settings. Parasequence stacking patterns are interpreted as resulting from regional fifth-order glacioeustatic sea-level changes consistent with established age constraints for fourth-order sequences. Detrended Correspondence Analysis (DCA) of paleontological bulk samples produced similar differentiation of habitats into carbonates and siliciclastics thereby demonstrating the importance of interpreting ordination patterns within a facies framework. The combined DCA analysis of samples and taxa indicates that bryozoans, crinoids and rugose corals preferentially occur in carbonate facies whereas brachiopods, the most dominant taxon, are abundant in both. Results suggest the presence of significant paleoenvironmental gradients in fossil associations that correlates to changes in hydrodynamic conditions and substrate composition across the depositional system. / Master of Science
3

Diversidade de bactérias do sedimento de manguezal da ilha do Cardoso Cananéia - São Paulo. / Bacterial diversity in sediment from mangrove of the island Cardoso Cananéia - São Paulo.

Dias, Armando Cavalcante Franco 22 February 2008 (has links)
O presente trabalho busca entender a dinâmica de comunidades bacterianas cultiváveis e não cultiváveis do ecossistema do manguezal e prospectar nesse ambiente ainda inexplorado, um possível potencial biotecnológico. As amostras de sedimentos foram retiradas de duas profundidades no inverno e no verão. Bactérias caracterizadas por meio da técnica de ARDRA pertencem as ordens Vibrionales, Bacillales e Actinomycetales. As espécies bacterianas cultiváveis e as não cultiváveis foram também avaliadas por meio da técnica de PCR-DGGE, onde utilizou-se iniciadores seletivos para Actinobacterias, a e b Proteobacteria, Pseudomonas spp. e Paenibacillus spp., além do universal para bacteria. A análise multivariada de redundância (RDA) permitiu verificar a relação dos perfis obtidos das amostras com os fatores ambientais. Verificou-se uma diferente distribuição dos grupos de a e b Proteobacteria em relação à sazonalidade, enquanto que a profundidade de amostragem mostrou ser essencial no perfil das comunidades totais, a e b-Proteobacteria e Actinobacterias. / The objective of the present work is the understanding of culturable and non-culturable bacterial community dynamic present in the mangrove ecosystem also to explore the biotechnological potential of bacteria present in this environmental. Sediment samples were obtained from two depths winter and summer seasons and further analyzed. The Bacteria were characterized by ARDRA and identified the orders Vibrionales, Bacillales e Actinomycetales. Culturable and non-culturable bacteria were also assessed by PCR-DGGE using specific primers for Actinobacteria, a-Proteobacteria, b-proteobacteria, Pseudomonas spp., Paenibacillus spp. and bacteria universal primers. Multivariate redundancy analysis allowed the verification of main factors determining the bacterial communities patterns found on samples. It was verified a seasonal distribution of a and b-Proteobacteria groups, while the sampled depth was determinant for the total bacterial community composition, and also influenced the a and b-Proteobacteria and Actinobacteria profiles.
4

Experimental manipulation of connectivity and common carp: the effects on native fish, water-column invertebrates, and amphibians in Delta Marsh, Manitoba

Parks, Candace R. 05 April 2007 (has links)
Common carp (Cyprinus carpio) have been hypothesized to contribute to declines in aquatic macrophytes, waterfowl, and water clarity in Delta Marsh, an 18,500 ha freshwater coastal wetland on Lake Manitoba, Canada. Ten ponds (1-13 ha) were chosen for a two-year experimental manipulation study. Following a year of baseline monitoring, manipulations were conducted in 2002. To facilitate access by carp into isolated ponds, channels were blasted from the main marsh into two ponds. Meanwhile, to restrict or exclude carp access into ponds, channels were either screened or diked to four ponds. Two connected and two isolated ponds functioned as controls. Although common carp were the original subject of the study, it became apparent that hydrological connection to the surrounding marsh had a paramount importance on the abundance and diversity of the fish, amphibian and water-column invertebrate communities. Connectivity, or lack of connectivity, played an important role in the distribution of the fish community, and subsequently the composition and abundance of water-column invertebrates and amphibians. Ponds with direct connection had diverse, mixed-species fish assemblages, with fewer invertebrates and amphibians. Ponds with restricted connections had fish communities composed of tolerant small-sized species and increased abundance of invertebrates and amphibians. Ponds that lacked connection could freeze and lose all fish, and had higher numbers of invertebrates and amphibians. An absence of adult common carp may have been responsible for increased amphibian numbers in the screened ponds, however more study is needed. Confounding impacts of fluctuating water levels made it impossible to implicate common carp for most changes observed within ponds in Delta Marsh. / May 2006
5

Experimental manipulation of connectivity and common carp: the effects on native fish, water-column invertebrates, and amphibians in Delta Marsh, Manitoba

Parks, Candace R. 05 April 2006 (has links)
Common carp (Cyprinus carpio) have been hypothesized to contribute to declines in aquatic macrophytes, waterfowl, and water clarity in Delta Marsh, an 18,500 ha freshwater coastal wetland on Lake Manitoba, Canada. Ten ponds (1-13 ha) were chosen for a two-year experimental manipulation study. Following a year of baseline monitoring, manipulations were conducted in 2002. To facilitate access by carp into isolated ponds, channels were blasted from the main marsh into two ponds. Meanwhile, to restrict or exclude carp access into ponds, channels were either screened or diked to four ponds. Two connected and two isolated ponds functioned as controls. Although common carp were the original subject of the study, it became apparent that hydrological connection to the surrounding marsh had a paramount importance on the abundance and diversity of the fish, amphibian and water-column invertebrate communities. Connectivity, or lack of connectivity, played an important role in the distribution of the fish community, and subsequently the composition and abundance of water-column invertebrates and amphibians. Ponds with direct connection had diverse, mixed-species fish assemblages, with fewer invertebrates and amphibians. Ponds with restricted connections had fish communities composed of tolerant small-sized species and increased abundance of invertebrates and amphibians. Ponds that lacked connection could freeze and lose all fish, and had higher numbers of invertebrates and amphibians. An absence of adult common carp may have been responsible for increased amphibian numbers in the screened ponds, however more study is needed. Confounding impacts of fluctuating water levels made it impossible to implicate common carp for most changes observed within ponds in Delta Marsh.
6

Experimental manipulation of connectivity and common carp: the effects on native fish, water-column invertebrates, and amphibians in Delta Marsh, Manitoba

Parks, Candace R. 05 April 2006 (has links)
Common carp (Cyprinus carpio) have been hypothesized to contribute to declines in aquatic macrophytes, waterfowl, and water clarity in Delta Marsh, an 18,500 ha freshwater coastal wetland on Lake Manitoba, Canada. Ten ponds (1-13 ha) were chosen for a two-year experimental manipulation study. Following a year of baseline monitoring, manipulations were conducted in 2002. To facilitate access by carp into isolated ponds, channels were blasted from the main marsh into two ponds. Meanwhile, to restrict or exclude carp access into ponds, channels were either screened or diked to four ponds. Two connected and two isolated ponds functioned as controls. Although common carp were the original subject of the study, it became apparent that hydrological connection to the surrounding marsh had a paramount importance on the abundance and diversity of the fish, amphibian and water-column invertebrate communities. Connectivity, or lack of connectivity, played an important role in the distribution of the fish community, and subsequently the composition and abundance of water-column invertebrates and amphibians. Ponds with direct connection had diverse, mixed-species fish assemblages, with fewer invertebrates and amphibians. Ponds with restricted connections had fish communities composed of tolerant small-sized species and increased abundance of invertebrates and amphibians. Ponds that lacked connection could freeze and lose all fish, and had higher numbers of invertebrates and amphibians. An absence of adult common carp may have been responsible for increased amphibian numbers in the screened ponds, however more study is needed. Confounding impacts of fluctuating water levels made it impossible to implicate common carp for most changes observed within ponds in Delta Marsh.
7

Aplicação de água residuária tratada de suinocultura em solo cultivado com soja

Smanhotto, Adriana [UNESP] 20 October 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-10-20Bitstream added on 2014-06-13T20:43:45Z : No. of bitstreams: 1 smanhotto_a_dr_botfca.pdf: 895309 bytes, checksum: d3cfd00c0ce1d5b6aaf6cf35b9ebc43b (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / Os dejetos gerados pela suinocultura vem tendo atenção especial em razão dos problemas ambientais causados pela sua destinação inadequada. A principal alternativa para o descarte do dejeto líquido de suínos é sua disposição no solo como fonte de nutrientes às plantas, além de economizar custos com fertilização e água. No entanto, faz-se necessário o estabelecimento de critérios para embasar taxas de aplicação adequadas, levando em consideração condições de solo, clima e culturas cultivadas na região. Desta forma, o objetivo deste trabalho foi avaliar possíveis efeitos da aplicação de diferentes taxas de água residuária de suinocultura (ARS) no solo e água percolada de lisímetros de drenagem, cultivados com soja. O experimento foi conduzido em ambiente protegido de 90 m2, no Núcleo Experimental de Engenharia Agrícola da UNIOESTE, cujo solo foi classificado como Latossolo Vermelho distroférrico típico. Na área de implantação havia vinte e quatro lisímetros de drenagem onde foi semeada soja, cultivar CD 202. Foram aplicadas ao solo quatro taxas de ARS (0; 100; 200 e 300 m3 ha-1 no ciclo), combinadas com duas adubações na semeadura (com adição e sem adição da adubação recomendada na semeadura), em três repetições por tratamento, divididas em seis aplicações ao longo do ciclo da soja. Fez-se irrigações de acordo com a precipitação média ocorrida no período, quinzenalmente, resultando em seis coletas do material percolado no qual foi determinado pH, nitrogênio total, nitrato, nitrito, fósforo, potássio, cobre e zinco. Realizou-se três coletas de solo em cada parcela experimental, antes da semeadura, aos 59 dias após a semeadura (DAS) e ao final do ciclo da soja. Determinou-se o pH, matéria orgânica, capacidade de troca catiônica, nitrogênio total, nitrato, fósforo, potássio, cobre e zinco no solo. O delineamento experimental... / Waste generated by swine has called special attention due to environmental problems caused by its inadequate disposal. A main alternative for the discarding of swine wastewater is its disposition in the soil as plant nutrient source, saving on fertilizing and water. However, it became necessary the establishment of criteria to ascertain adequate application rates taking in consideration soil condition, climate, and cultures planted in the region. Thus, the objective of this paper is to evaluate the possible effects in applying different rates of swine wastewater (ARS) in the soil, and drainage lysimeter lixiviated water cultivated with soybeans. The experiment was conducted in a 90-m2 protect environment at UNIOESTE`s Agricultural Engineering Experimental Nucleus, which soil was classified as Distroferic Red Latosoil (oxisol). The implanted area contained twenty-four lysimeters of drainage where the soy cultivar CD 202 was sown. Four rates of ARS were applied (0; 100; 200 e 300 m3 ha-1 in the cycle) combined with two fertilizing at sewing (with and without added fertilizing recommended at sewing), repeated three times per treatment, divided in six application throughout the cultivar cycle. Irrigation was performed every fifteen days according to the average precipitation during that period resulting in six samplings of the lixiviated material from which pH, total nitrogen, nitrate, phosphorous, potassium, copper, and zinc content was determined. Three soil samples, from each experimental parcel, were taken; one at sewing, another 59 days after sewing (DAS), and the last one at the final cycle of the cultivar. Organic matter, pH, cationic exchange capacity, total nitrogen, nitrate, phosphorous, potassium, copper, and zinc in soil were determined. The experiment delimitation was done in... (Complete abstract click electronic access below)
8

Diversidade fenotípica e qualidade em sementes de cultivares de soja / Phenotypic diversity and quality in soybean cultivars seeds

Camargos, Ayza Eugênio Viana [UNESP] 04 July 2017 (has links)
Submitted by AYZA EUGENIO VIANA CAMARGOS null (ayzacamargos@hotmail.com) on 2017-09-01T06:31:28Z No. of bitstreams: 1 ayzadissertacao.pdf: 1919998 bytes, checksum: 34d5348390697bbe32dd13a74438ff11 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-09-01T16:21:50Z (GMT) No. of bitstreams: 1 camargos_aev_me_bot.pdf: 1919998 bytes, checksum: 34d5348390697bbe32dd13a74438ff11 (MD5) / Made available in DSpace on 2017-09-01T16:21:50Z (GMT). No. of bitstreams: 1 camargos_aev_me_bot.pdf: 1919998 bytes, checksum: 34d5348390697bbe32dd13a74438ff11 (MD5) Previous issue date: 2017-07-04 / Em função de identificar potenciais parentais a serem utilizados por um programa de melhoramento visando alta qualidade fisiológica de sementes e boa produção de sementes, o objetivo do trabalho foi avaliar a diversidade fenotípica através de caracteres agronômicos que afetam a produção de sementes e o potencial fisiológico de 32 cultivares comerciais brasileiras de soja, possibilitando futura seleção das melhores cultivares para compor um programa de melhoramento genético direcionado ao Cerrado brasileiro. Foram avaliadas oito características fenotípicas e sete para qualidade fisiológica de sementes. As análises das características quantitativas foram conduzidas por técnicas de estatística multivariada e componentes principais. Para os testes de qualidade fisiológica de sementes, o delineamento experimental utilizado foi inteiramente casualizado (DIC), os dados foram submetidos à análise de variância, ao teste F e teste Scott-Knott a 5% de significância. As cultivares AS 3797IPRO, AS 7307RR, CD 2728IPRO, CD 2820IPRO, TMG2181IPRO e TMG2183IPRO, foram selecionadas por obterem as melhores estimativas quanto à qualidade fisiológica de sementes, no entanto, não foram as que apresentaram as maiores produtividades. Sendo assim, as análises estatísticas utilizadas possibilitaram à diferenciação e agrupamento entre as cultivares comerciais estudadas para a diversidade fenotípica e o potencial fisiológico, possibilitando a escolha dos melhores genótipos quanto aos caracteres agronômicos e qualidade de sementes de maior importância para seleção de cultivares neste trabalho. / In order to identify characteristics that helps in the selection of superior genotypes to be used by a breeding program, aiming high physiological quality of seeds and good seed production, the main objective of this study was evaluate the phenotypic diversity through agronomic traits affecting seed production and the physiological potential of 32 Brazilian soybean cultivars, enabling future selection of the best cultivars to be part of a soybean breeding program directed to the Brazilian Savana. Eight agronomic traits and seven physiological quality seeds characteristics were evaluated. Analyzes of the quantitative features were conducted using multivariate statistical techniques and main components. For the seed physiological quality tests, the experimental design was completely randomized (DIC), the data were submitted to analysis of variance, F test and Scott-Knott test at 5% of significance. The cultivars AS 3797IPRO, AS 7307RR, CD 2728IPRO, CD 2820IPRO, TMG2181IPRO and TMG2183IPRO were selected for obtaining the best estimates regarding the physiological quality of seeds, however, they weren’t those that presented the greatest seeds production. Therefore, the statistical analyzes allowed the differentiation and grouping between the commercial cultivars studied for the phenotypic diversity and the seeds physiological potential, allowing the selection of the best genotypes to the agronomic traits and seed quality judged of greater importance to selection in this experiment.
9

Abordagens multivariadas no estudo da dinâmica de comunidades de macrófitas aquáticas

Pitelli, Robinson Luiz de Campos Machado [UNESP] 04 September 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-09-04Bitstream added on 2014-06-13T21:01:00Z : No. of bitstreams: 1 pitelli_rlcm_dr_fca.pdf: 512956 bytes, checksum: b7f67dd4835b4a602a6198adbffcab0c (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / The aquatic weeds are essentially important in water bodies under strong antropic influence, especially in hydropower water reservoirs built-up in highly urbanized regions. In the energy generation system of hydropower company Light Serviços de Eletricidade , the Santana reservoir historically has more problems with aquatic weeds. Aiming to solve these problems the company periodically promotes a mechanical harvesting cleaning up the reservoir, but after some time it is completely re-colonized by the macrophytes and the 4 problems are back. Aiming to understand the macrophytes re-colonization dynamics, fields surveys were done monthly, identifying and quantifying the aquatic weed populations in 91 sampling sites. The weeds quantification was done by means of a colonization scale changing from 0 (no plants) to 4 (high colonization, more than 80% of the sampling site). The evolution of colonization area and the geographic distribution pattern were studied for aquatic weed populations, while diversity and equitability coefficients, several similarity index and multivariate analysis were applied to study the macrophyte communities between sampling times. There was a well defined colonization succession process, characterized by variation in the relative size of the different populations and some seral stages could be established, at least for mechanical harvesting planning and some biotic conditions of the macrophyte community. It was not possible to detect a succession of populations, but a succession of colonization conditions since there were no expressive increments or extinctions of species in the reservoir during the year. The exotic species to the reservoir and with early colonization were the predominant ones in the macrophyte community with special attention to Egeria densa and Brachiaria arrecta. For some species, as Eichhornia crassipes and Myriophyllum aquaticum, the biotic pressures of natural enemies probably had decisive effects on.
10

Diversidade de bactérias do sedimento de manguezal da ilha do Cardoso Cananéia - São Paulo. / Bacterial diversity in sediment from mangrove of the island Cardoso Cananéia - São Paulo.

Armando Cavalcante Franco Dias 22 February 2008 (has links)
O presente trabalho busca entender a dinâmica de comunidades bacterianas cultiváveis e não cultiváveis do ecossistema do manguezal e prospectar nesse ambiente ainda inexplorado, um possível potencial biotecnológico. As amostras de sedimentos foram retiradas de duas profundidades no inverno e no verão. Bactérias caracterizadas por meio da técnica de ARDRA pertencem as ordens Vibrionales, Bacillales e Actinomycetales. As espécies bacterianas cultiváveis e as não cultiváveis foram também avaliadas por meio da técnica de PCR-DGGE, onde utilizou-se iniciadores seletivos para Actinobacterias, a e b Proteobacteria, Pseudomonas spp. e Paenibacillus spp., além do universal para bacteria. A análise multivariada de redundância (RDA) permitiu verificar a relação dos perfis obtidos das amostras com os fatores ambientais. Verificou-se uma diferente distribuição dos grupos de a e b Proteobacteria em relação à sazonalidade, enquanto que a profundidade de amostragem mostrou ser essencial no perfil das comunidades totais, a e b-Proteobacteria e Actinobacterias. / The objective of the present work is the understanding of culturable and non-culturable bacterial community dynamic present in the mangrove ecosystem also to explore the biotechnological potential of bacteria present in this environmental. Sediment samples were obtained from two depths winter and summer seasons and further analyzed. The Bacteria were characterized by ARDRA and identified the orders Vibrionales, Bacillales e Actinomycetales. Culturable and non-culturable bacteria were also assessed by PCR-DGGE using specific primers for Actinobacteria, a-Proteobacteria, b-proteobacteria, Pseudomonas spp., Paenibacillus spp. and bacteria universal primers. Multivariate redundancy analysis allowed the verification of main factors determining the bacterial communities patterns found on samples. It was verified a seasonal distribution of a and b-Proteobacteria groups, while the sampled depth was determinant for the total bacterial community composition, and also influenced the a and b-Proteobacteria and Actinobacteria profiles.

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