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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.
61

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura Unknown Date
No description available.
62

MATRIX GEOCHEMISTRY AND PHYTOPHTHORA OCCURRENCE ON REFORESTED MINE LANDS IN APPALACHIA

Ward, Kathryn M. 01 January 2009 (has links)
At the Bent Mountain surface mine, Pike County, Kentucky, a study has been ongoing since 2005 to assess the influence of various types of loose-graded mine spoils on water quality and forest establishment. Six research plots consist of two replicates of brown weathered sandstone, gray unweathered sandstone, and mixed brown sandstone, gray sandstone, and shale that were emplaced according to Forestry Reclamation Approach criteria. A series of analyses was initiated in 2007 to examine influence of spoil matrix composition on sulfate and carbonate geochemistry of infiltrated waters, as well as to investigate the occurrence of Phytophthora, a group of exotic forest pathogens that cause dieback and may affect success of founder species of hybrid American Chestnut (Castanea dentata Marsh.) Borkh.)), on the surface of mine spoils and in infiltrated waters. To identify the constituent responsible for elevated sulfate concentrations, as well as determine the role of alkalinity in spoil waters, PHREEQC geochemical modeling was used to analyze aqueous speciation of sulfates and carbonates with respect to time and tailing media. Variance of δ34S values was analyzed to determine source of sulfate minerals. Oxidation of minor amounts of pyritic coal enriched the δ34S value in the brown plots. Overall, plots had acceptable water quality parameters, substantiating various types of mine spoils for the FRA, although brown proved best for tree establishment. Methods were employed to determine whether Phytophthora were present in the surface of mine spoils and in infiltrated waters of 2005 plots as well as 2007 plots to determine if a chronosequential effect occurred. P. cryptogea was detected from surface spoil and from waters infiltrating brown sandstone plots. The brown spoil, relative to other spoil types, has greater soil moisture, greater nutrient availability, and lower pH, which may promote the occurrence and survival of the microorganism. The occurrence of the pathogen in the 2005 plots versus 2007 plots is notable; greater ground cover from colonizing species may be a precursor to Phytophthora detection on the plots. P. cryptogea is a possible threat to American chestnut, however, high infiltration rates in loose-dumped mine spoils should reduce damage by the pathogen. Over time, the relation between water quality parameters (as influenced by spoil matrix composition), tree success, and presence of Phytophthora, is of interest as certain hydrogeochemical parameters may cause stress on trees that may increase susceptibility of plants to disease caused by Phytophthora. Alternatively, certain water geochemical parameters may directly affect Phytophthora by promoting or inhibiting survival and transport of the pathogen in spoil and infiltrated spoil waters; this too has consequences for tree establishment on loose-dumped mine spoils.
63

Two-year performance of hybrid and pure American chestnut Castanea dentata (Fagaceae) seedlings and benefit of Pisolithus tinctorius (Sclerodermataceae) on eastern Ohio mine spoil

Herendeen, Robert V. January 2007 (has links)
Thesis (M.S.)--Ohio University, June, 2007. / Title from PDF t.p. Includes bibliographical references.
64

Estudo comparativo de raÃzes de Jatropha mollissima sertÃo/praia, das castanhas de caju (anacardium occidentale l.) de diferentes plantios e estudo in vitro e in silico de compostos com potencial de inibiÃÃo da enzima conversora de angiotensina. / Comparative study of the roots of Jatropha mollissima backcountry / beach of cashew nuts (Anacardium occidentale l.) Of different crops and study in vitro and in silico compounds with potential inhibition of angiotensin converting enzyme.

Samuel Josà Mendes dos Santos 31 January 2014 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A hipertensÃo arterial à uma doenÃa que afeta milhÃes de pessoas em todo o mundo e dentre seus principais fatores causadores destacam-se uma dieta pouco saudÃvel, falta de exercÃcios fÃsicos e obesidade. A inibiÃÃo da enzima conversora da angiotensina (ECA) foi identificada como um alvo terapÃutico para controlar a pressÃo arterial elevada, pois o octapeptÃdeo angiotensina II, que possui atividade vasoconstritora, terà sua atividade minimizada nos vasos sanguÃneos. Compostos encontrados na casca da castanha de caju foram separados e identificados e seu potencial de inibiÃÃo da ECA foi estudado. Observou-se que os Ãcidos anacÃrdicos possuem essa atividade, sendo o Ãcido 3-anacÃrdico o maior inibidor entre os compostos fenÃlicos extraÃdos da casca da castanha de caju. Estudos in silico sÃo realizados atualmente para predizer a biodisponibilidade oral e a capacidade de penetraÃÃo no sistema nervoso central (SNC) de uma droga. Buscou-se realizar este estudo para verificar essas propriedades nos Ãcidos anacÃrdico, assim como tambÃm, comparar com outros inibidores da ECA. Observou-se que os Ãcidos anacÃrdicos violam somente uma das cinco regras de Lipinski, e como a regra estabelece que pelo menos trÃs destes requisitos devam ser satisfeitos, conclui-se que os Ãcidos anacÃrdicos apresentam uma boa biodisponibilidade oral e penetraÃÃo no SNC. Desse modo, a busca por uma espÃcie de clone que forneÃa uma maior massa de LCC por extraÃÃo assim como uma maior quantidade de Ãcidos anacÃrdicos por quilograma de LCC se torna importante. A partir disso, verificou-se entre cinco cultivos de cajueiros anÃes (CCP-76, CCP-09, Embrapa-110, Embrapa-119 e Embrapa-109) o que poderia oferecer um LCC com maior quantidade de Ãcidos anacÃrdicos. O cajueiro identificado como CCP-76 forneceu uma maior quantidade de LCC com cerca de 30 gramas para cada 50 gramas de casca de castanha utilizada para extraÃÃo e se obteve uma concentraÃÃo de 185 gramas de Ãcidos anacÃrdico por quilograma de LCC, sendo o melhor para extraÃÃo dos alquilfenÃis, entre os estudados. Em paralelo a esses estudos, procurou-se verificar a diferenÃa de compostos existentes na raiz de Jatropha mollissima cultivada em regiÃes diferentes e verificou-se que o estresse do sertÃo cearense aumenta a sÃntese de substÃncias para a sua sobrevivÃncia, sendo a raiz a regiÃo da planta escolhida por ser rica em metabolitos secundÃrios. Assim, essas plantas podem ser utilizadas na medicina preventiva, porÃm, estudos mais profundos devem ser realizados. / Hypertension is a disease that affects millions of people around the world and among its main causative factors include an unhealthy diet, lack of physical exercise and obesity. Inhibition of angiotensin converting enzyme (ACE) has been identified as a therapeutic target for controlling high blood pressure because the octapeptide angiotensin II, which has vasoconstrictor activity, have minimized their activity in blood vessels. Compounds found in the bark of cashew nuts were separated and identified, and their potential for ACE inhibition was studied. It was observed that the anacardic acids possess this activity, being the 3-anacardic acid inhibitor best among the largest phenolic compounds extracted from the bark of cashews. In silico studies are currently performed to predict the bioavailability and the ability to penetrate the central nervous system (CNS) of a drug. We attempted to conduct this study to verify these properties in anacardic acids, as well as compare with other ACE inhibitors. It was observed that the anacardic acids infringe only one of the five rules of Lipinski, and as the rule states that at least three of these requirements must be satisfied, it is concluded that the anacardic acids exhibit good oral bioavailability and CNS penetration. Thus, the search for a cashew that provides a greater mass of LCC per extraction well as a greater amount of anacardic acid per kilogram of LCC becomes important. From this, it was found among five crops of dwarf cashew (CCP-76, CCP- 09, Embrapa-110, Embrapa-119 and Embrapa-109) which could offer a LCC with greater amount of anacardic acids. The cashew labeled CCP-76 gave a higher amount of LCC to about 30 grams per 50 grams of chestnut bark used for extraction and obtained a concentration of 185 grams per kilogram of anacardic acids LCC to be the best extraction of alkylphenols, among studied. In parallel to these studies, we sought to investigate differences existing compounds in Jatropha mollissima grown in different regions, and it was found that the stress of Cearà hinterlands increases the synthesis of substances for their survival. Thus, these plants can be used in preventive medicine, however, further study should be conducted.
65

Obtenção e caracterização da farinha de castanha (Castanea spp.) e seu potencial de aplicação em produtos de panificação / Obtaining and characterization of chestnut (Castanea spp.) flour and its potential application in bakery products

Moreira, Ana Cláudia Varanda, 1985- 12 March 2014 (has links)
Orientador: Caroline Joy Steel / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T00:29:09Z (GMT). No. of bitstreams: 1 Moreira_AnaClaudiaVaranda_M.pdf: 2755890 bytes, checksum: d8415f5cd4d888a1a91888ab6d03b7bc (MD5) Previous issue date: 2014 / Resumo: Apesar de ser um produto comercialmente muito importante nos países europeus, principalmente em Portugal, e em alguns países asiáticos, tais como a Turquia e a China, a produção e comercialização dos diferentes tipos de castanha do gênero Castanea spp. em grande escala no Brasil está restrita a algumas regiões específicas, de clima mais ameno, a exemplo das regiões de maior altitude do estado de São Paulo, visto que ela é altamente perecível e suscetível à contaminação por fungos, o que requer estocagem sob temperaturas de refrigeração. Entretanto, sua farinha pode ser conservada por mais tempo à temperatura ambiente; além disso, esta possui alto teor de amido, tendo sido encontrado alto teor de amido resistente. Ainda, a farinha de castanha possui conteúdo significativo de proteínas e um baixo teor de lipídeos. No Brasil, a farinha de castanha não é encontrada comercialmente e a sua produção a partir das sementes colhidas ainda não foi amplamente estudada, nem a sua aplicação. Por conseguinte, o objetivo deste trabalho foi avaliar o melhor método de obtenção da farinha de castanha (Castanea spp.), bem como caracterizá-las com relação à sua composição centesimal, características reológicas, propriedades de pasta e teor de amido resistente. Para tanto, foram obtidas três amostras de farinha de castanha por diferentes métodos, avaliando-se a possibilidade de sua aplicação em produtos de panificação, mais especificamente, em bolo inglês e em biscoito tipo cookie. As 3 farinhas obtidas foram analisadas em sua composição centesimal, cor, fibra alimentar, amido resistente e análise reológica em blends com farinha de trigo. Os cookies e os bolos produzidos foram avaliados quanto ao teor de fibra alimentar e amido resistente, bem como quanto à textura, umidade e atividade de água ao longo do armazenamento. Quanto aos resultados, a farinha Integral apresentou 7,6+0,3% de umidade, 1,49+0,07% de lipídeos, 4,61+0,17% de proteínas, 2,03+0,08% de cinzas e 16,75+0,45% de fibra alimentar. Já a farinha Refinada possuiu 7,12+0,19% de umidade, 1,39+0,39% de lipídeos, 4,50+0,03% de proteínas, 2,23+0,03% de cinzas e 10,88+0,43% de fibra alimentar. A farinha Seca Inteira possuiu 7,49+0,07% de umidade, 1,25+0,13% de lipídeos, 4,05+0,15% de proteínas, 2,15+0,02% de cinzas e 11,93+0,27% de fibra alimentar. Os teores de fibra alimentar e amido resistente nos bolos elaborados com farinha de castanha foram significativamente maiores que os constatados na formulação controle e, durante a estocagem, houve pouca alteração nos teores de umidade e atividade de água dos bolos, enquanto que, no que diz respeito ao parâmetro "textura", observou-se um aumento significativo da firmeza entre os dias 5 e 10 de estocagem. Já os cookies elaborados com farinha de castanha obtiveram maiores teores de fibra alimentar e de amido resistente que o controle, além de maior espalhabilidade. Por fim, os bolos e biscoitos foram submetidos à análise sensorial de aceitação e intenção de compra, todos obtendo notas de aceitação entre 6 (gostei ligeiramente) e 7 (gostei moderadamente), o que denota grande potencial de aplicação da farinha de castanha em produtos de panificação / Abstract: Despite being a very important commercial product in European countries, especially in Portugal, and in some Asian countries, such as Turkey and China, production and trade of different varieties of chestnut genus Castanea spp. in large scale in Brazil is restricted to specific regions of milder weather, such as the ones with higher altitudes in the state of São Paulo. The chestnut is highly perishable and very susceptible to contamination by fungi, requiring storage at refrigeration temperatures. However, chestnut flour can be stored for a longer time at room temperature; furthermore, this flour has high starch content and it has been found to have high resistant starch content. Also, chestnut flour has significant protein content, and it has low lipid content. In Brazil, chestnut flour is not commercially produced and its production from harvested seeds has not been widely studied, neither its application. Therefore, the aim of this study was to evaluate the best method of obtaining chestnut (Castanea spp.) flour, as well as to characterize the chestnut flours as to their chemical composition, rheological properties, pasting properties and resistant starch content. Three samples of chestnut flour were obtained by different production methods. Finally, the possibility of applying the flour in bakery products was evaluated, more specifically, pound cakes and cookies, for the purpose of nutritional enrichment of the products. The 3 flours obtained were analyzed for their chemical composition, color, dietary fiber, resistant starch and rheological analyses in blends with wheat flour. Cookies and pound cakes produced were evaluated for dietary fiber and resistant starch as well as texture, moisture and water activity during storage and sensory analysis of acceptance and purchase intent was performed. Whole flour had 7.6+0.3% moisture, 1.49+0.07% fat, 4.61±0.17% protein, 2.03±0.08% ash and 16.75+0.45% dietary fiber. Refined flour had 7.12+0.19% moisture, 1.39 +0.39% fat, 4.50+0.03% protein, 2.23+0.03% ash and 10.88+0.43% dietary fiber. Dried Whole flour had 7.49+0.07% moisture, 1.25+0.13% fat, 4.05+0.15% protein, 2.15+0.02% ash and 11.93+0.27% dietary fiber. The levels of dietary fiber and resistant starch in the cakes elaborated with chestnut flour were significantly higher than in the control. During storage, there was little change in moisture content and water activity of the cakes, but firmness showed a significant increase between the 5th and the 10th day of storage. Cookies made with chestnut flour showed higher spreadability and higher dietary fiber and resistant starch contents than the control. Both cookies and cakes evaluated presented acceptance scores between 6 (like slightly) and 7 (like moderately) showing the great potential of application of chestnut flour in bakery products / Mestrado / Tecnologia de Alimentos / Mestra em Tecnologia de Alimentos
66

Aspergillus section Nigri produtores de fumonisina B2 isolados de castanha-do-brasil. / Aspergillus section Nigri producing fumonisin B2 from Brazil nuts.

Ferranti, Larissa de Souza 14 December 2012 (has links)
A castanha-do-brasil é uma planta de grande importância econômica na região da Amazônia. Os baixos níveis tecnológicos característicos de sua cadeia produtiva e as condições inadequadas de manejo da matéria prima, favorecem o aparecimento de contaminação por fungos produtores de micotoxinas. A fumonisinas B2 (FB2) é uma micotoxina produzida por espécies de Fusarium e Aspergillus section Nigri, e é motivo de preocupação para a saúde humana e de animais. O objetivo do presente trabalho foi verificar o potêncial toxigênico quanto à produção de fumonisina B2 das cepas de A. section Nigri isolados de castanha-do-brasil e verificar a contaminação desse alimento por essa micotoxina. De um total de 200 cepas de A. section Nigri testadas quanto à capacidade de produção de fumonisina B2, apenas 39 cepas (19,5 %) produziram FB2, cento e trinta e oito (69 %) não foram produtoras de fumonisina B2 e 23 cepas (11,5 %) apresentaram picos menores que o limite de detecção. Das 100 amostras de castanha-do-brasil analisadas, nenhuma estava contaminada por fumonisina B2. / Brazil nut is a plant with vast economic importance in the Amazon region and is an important product exported by Brazil. However, low levels of technology, and inadequate management of raw material favor the appearance of contamination by fungi that produce toxic metabolites called mycotoxins. Fumonisin B2 (FB2) is a mycotoxin produced by Fusarium species and Aspergillus section Nigri, and is of concern for human health. The aim of this study was to assess the toxigenic potential for fumonisin B2 production by Aspergillus section Nigri strain isolated from brazil nut and check the contamination of food by this mycotoxin. From a total of 200 strains of Aspergillus section Nigri tested for the ability to produce fumonisin B2, only 39 strains (19.5 %) were producing FB2, 138 (69 %) were not producing fumonisin B2, and 23 strains (11.5 %) showed peaks less than the detection limit. Of the 100 samples of brazil nuts analyzed, none were contaminated with fumonisin B2.
67

Population-level and Individual-level Drivers of Reproduction in Chestnut Oak (Quercus montana Willd.) and Black Oak (Q. velutina Lam.) in Southeast Ohio

Smith, Sarah J. January 2019 (has links)
No description available.
68

CPVIB-1, a GAGA Regulator of TOR Signaling Pathways in the Chestnut Blight Pathogen Cryphonectria Parasitica

Ren, Di 10 August 2018 (has links)
Cryphonectria parasitica is the causal agent of chestnut blight, which devastated the American Chestnut tree population in the early 20th century. The discovery of hypoviruses that reduce the severity of the chestnut blight infection offers the potential for biological control. However, the spread of the hypoviruses is hampered by a diverse genetically controlled nonself-recognition system, vegetative incompatibility (vic). CPVIB-1 was identified as a transcription regulator playing an important role in the programmed cell death response to this stimulus. In this study, we have found that CPVIB-1 is ubiquitin-decorated which might lead to its degradation in the proteasome pathway. RNA-Seq and ChIP-Seq were used to further explore the downstream targets of CPVIB-1 that mediate the various metabolic changes that lead to the altered phenotype of the Δcpvib-1 mutant. Due to inaccuracies in the prior annotation, we performed a genome re-annotation to improve the accuracy using a MAKER2-two-pass pipeline. To validate the improvement a second pipeline, PEPA, was developed to compare quality metrics between the old and new annotations. Approximately 1/3 of the original annotations from 2009 were found to be inaccurate. Experimental confirmation by testing 27 predicted genes using a diagnostic PCR protocol to differentiate between prior and new transcript structures showed that over 80 % of tested genome locations supported for the new annotation. Using rapamycin treatment to mimic stimulation of the vic response and applying the RNA-seq and ChIP-seq data to this new information, we found that CPVIB-1 is related to TOR signaling pathways, promoting autophagy and the proteasome pathway, but repressing carbon metabolism, protein and lipid biosynthesis. In depth analysis of CPVIB-1-bound DNA targets showed that this protein is a member of the GAGA regulator family, a group of multifaceted transcription factors with diverse roles in gene activation and repression, maintenance of mitosis, and cell development. Following treatment with rapamycin the recognition sequence bound by CPBVIB-1 was altered leading to the regulation of different suite of genes with diverse metabolic functions. Ultimately, we have developed a revised model of TOR signaling pathway where TORC1 and TORC2 signaling pathways are connected by the action of CPVIB1.
69

Morphological Tradeoffs of American Chestnut (Castanea Dentata) and Co-Occurring Hardwoods in Varying Nutrient and Light Regimes

Thomas, Dana J. 19 December 2005 (has links)
No description available.
70

ECTOMYCORRHIZAL COMMUNITIES ASSOCIATED WITH RESTORATION PLANTINGS OF AMERICAN CHESTNUT (CASTANEA DENTATA) SEEDLINGS ON OHIO MINE LANDS: PLANTING METHODOLOGIES TO PROMOTE ROOT COLONIZATION

Bauman, Jenise M. 13 December 2010 (has links)
No description available.

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