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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.
11

Synthesis of ammonium, sodium, and potassium fluoroionohpores

Dennen, Katherine Faye. January 2002 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: Ionophores; Fluoroionohpores; Optical Sensors. Includes bibliographical references (p. 89-92).
12

Sterol-based ionophores /

Osifchin, Manette A., January 1999 (has links)
Thesis (Ph. D.)--Lehigh University, 2000. / Includes vita. Includes bibliographical references (leaves 146-152).
13

The design and synthetic studies of N / |-[1-(carboxy)-9,11,21-(trioxo)-heneicosyl]-l-aspartyl-l-lysyl-(tert-butyl)-l-asparaginate, a tripeptide analogue of ionomycin

Putland, Michael Stuart January 1990 (has links)
Ionomycin is a stereochemically complex calcium ionophore. An analogue (34) of ionomycin has been designed and its synthesis initiated. Regions of the analogue which parallel portions of ionomycin do not incorporate any of the chiral centers found in the natural product. The analogue 34 also incorporates a highly conserved tripeptide found in the calcium binding site of troponin C proteins. [ Formula omitted ] / Science, Faculty of / Chemistry, Department of / Graduate
14

Synthesis of Ammonium, Sodium, and Potassium Fluoroionohpores

Dennen, Katherine Faye 06 September 2002 (has links)
"N-(1-methylpyrene) monoaza-15-crown-5 (P5), N-(1-methylpyrene) monoaza-18-crown-6 (P6), N-(9-anthryl-methyl) monoaza-15-crown-5 (A5), N-(9-anthryl-methyl) monoaza-18crown-6 (A6), were synthesized and tested as fluoroionophores for potassium and sodium cations. Upon metal ion complexation, fluorescence yields increased dramatically due to an internal photoinduced electron transfer quenching mechanism (an off-on fluorescence switch). The results for these model compounds led to the design and synthesis of 1,3 alternate calixarene[4]arenecrown-5 (I) and bicyclic peptide (V). Calixarene I was synthesized and found to selectively complex potassium cations as predicted. The design of bicyclic peptide V is directed toward the selective complexation of ammonium cations. The synthesis of V involved the preparation of an open chain hexa-peptide consisting of two trityl-protected homoserine residues. Addition of an amino methyl pyrene across two homoserine residues was attempted by triflating the alcohols. The cyclization of the peptide ring is expeded to produce a basket-like structure that molecular modeling indicates should have improved selectivity over that of nonactin, the current industry standard."
15

Spectral and electrochemical study of the response of mechanism of ionphore-based polymeric membranes

Long, Robert F., January 2006 (has links) (PDF)
Dissertation (Ph.D.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.
16

Lead transport properties of carboxylic acid and synthetic ionophores

Hamidinia, Shawn A., January 2005 (has links)
Thesis (Ph.D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xv, 157 p.; also includes graphics. Includes bibliographical references (p. 142-157). Available online via OhioLINK's ETD Center
17

Exploratory study of ionophoric spiroethers and spioketals

Selvaraj, Peter Rajan 22 September 2006 (has links)
No description available.
18

Design, synthesis, and evaluation of bicyclic peptides as ammonium ionophores

Nowak, Cheryl L. January 2003 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: solution 13C-NMR study; olid phase peptide synthesis; bicyclic peptides; ammonium ionophores; valinomycin; ion selective electrode. Includes bibliographical references (p. 63-65).
19

Aditivos antimicrobianos e processamento de grão na terminação bovinos de corte confinados / Antimicrobial additives and grain processing for finishing of feedlot beef cattle

Camilo, Fernando Rossi 17 February 2017 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-03-02T20:52:11Z No. of bitstreams: 2 Tese - Fernando Rossi Camilo - 2017.pdf: 10483228 bytes, checksum: d18a7df8668d91f8363cc97be37de4e8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-03T11:40:23Z (GMT) No. of bitstreams: 2 Tese - Fernando Rossi Camilo - 2017.pdf: 10483228 bytes, checksum: d18a7df8668d91f8363cc97be37de4e8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-03T11:40:23Z (GMT). No. of bitstreams: 2 Tese - Fernando Rossi Camilo - 2017.pdf: 10483228 bytes, checksum: d18a7df8668d91f8363cc97be37de4e8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-17 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / The experiment 1 objectives were to evaluate the isolated and combined effects of the virginiamycin (VM) and monensin sodium (MON) on performance, feed intake, feed efficiency, ruminal fermentation, and carcass characteristics of beef cattle fed with high concentrate diet, the experiment 2 had the objective evaluate ruminal parameter the bulls Nelore with use the isolated and combined effects of the virginiamycin (VM) and monensin sodium (MON) and the experiment 3 had the objective to determine the optimal moisture content for reconstituted ensiled corn grain, evaluating final moisture concentrations of 27%, 30%, 33%, and 36%. In Exp. 1, 339 crossbred bulls Nellore x Guzera; were used in a randomized complete block design with five treatments and seven replicates. The blocks were defined by initial body weight. The animals were allocated in group pens for 103d, including 28d adaptation period. Treatments were defined by levels of VM and MON (mg/kg of DM) as follows: 30MON; 15VM+30MON; 25VM+30MON; 34VM+ 30MON e 34VM. In the phase of adaptation was no statistical (P>0.05) in body weight initial, body weight final, and average daily gain. Already to dry matter intake have the statistical difference (P<0.05) to compare 30MON vs 34MON e 34VM vs 34VM+30MON, in the phase adaptation the dose association 34VM+30MON have the smaller dry matter intake. In Exp. 2, 15 Nellore bulls with ruminal cannula were used in a randomized complete block design with 5 treatments and 3 replicates. Animals were blocked by initial body weight. The animals were kept in individual pens for 35 days has received the same diet to Exp.1. The sample liquid ruminal was collected in days 0, 7, 14, 21, and 28 for evaluation pH, VFA, N-NH3, and protozoan. After this period was realized the digestibility. The values of pH, NH3-N, and VFA were no differences (P>0.05) for contrast and linear and quadratic regression, except for acetic acid concentration that was difference (P<0.05). The protozoa concentration total had effect in contrast 34VM vs 34VM+30MON (P<0.05), being that the dose 34VM provide more concentration. In the Exp.3 sixty cattle (Bos taurus) were randomized complete block design with 6 treatments and 10 replicates was used. The treatments were corn grain reconstituted with water until they reach to final moisture concentrations of 27 (HMC27%), 30 (HMC30%), 33 (HMC33%), and 36% (HMC36%) and grains were allowed to ensile for 101 days. The steam-flaker corn and dry-rolled corn also were usually with treatment. Were no statistical difference (P<0.05) in performance the cattle confined for 89 days. Already in experiment in vitro the gas production the high moisture corn. To usually the high moisture corn in diet the cattle no increased the performance. Already the processing corn were availed in vitro, high moisture result in high fermentation and gas production. / No Exp. 1, o objetivou-se avaliar os efeitos isolados e combinados de virginiamicina (VM) e monensina sódica (MON) no desempenho, consumo, eficiência alimentar e características de carcaça e composição corporal de bovinos cruzados alimentados com dieta de alto teor de concentrado, enquanto o Exp. 2 o objetivou-se avaliar os parâmetros ruminais de bovinos Nelore confinados com o uso isolado e combinado de virginiamicina (VM) e monensina sódica (MON). Um terceiro experimento (Exp. 3) foi conduzido a fim de determinar o teor de umidade ideal para umidade. No Exp. 1 foram utilizados 330 animais mestiço nelore x guzerá que foram blocados peso corporal e randomizados em baias coletivas em um delineamento de blocos casualizados, com cinco tratamentos e sete repetições. O experimento teve duração 103 dias, sendo 28 dias de adaptação. Os tratamentos foram compostos por doses de VM e MON em mg/kg de matéria seca e suas associações, sendo: 30MON; 15VM+30MON; 25VM+30MON; 34VM+30MON e 34VM. Na fase da adaptação, não foi observado diferenças (P>0,05) no peso inicial, peso final e ganho médio diário. Já para ingestão de matéria seca houve diferença (P<0,05), quando comparado 30 MON vs 34 MON e 34VM vs 34VM+30MON, na fase de adaptação a dose associada 34VM+30MON teve menor ingesta de matéria seca. No Exp. 2 foram utilizados 15 animais da raça Nelore canulados no rúmen, que foram alocados em baias individuais randomizados e blocados pelo peso corporal, com cinco tratamentos e três repetições. Os animais foram mantidos em confinamento por 35 dias recebendo a mesma dieta descrita no Exp. 1. Amostras de líquido ruminal foram coletadas nos dias 0, 7, 14, 21 e 28 para avaliar pH, AGV, nitrogênio amoniacal (N-NH3) e protozoários. Após esse período foi realizado um ensaio de digestibilidade para mensurar a utilização de nutrientes. Os valores de pH, N-NH3 e AGV não foram encontrados diferenças (P>0,05) para os contrastes e regressão linear e quadrática, exceto para a concentração de ácido acético (P<0,05). A concentração total de protozoários foi maior para 34VM quando comparada com 34VM vs 34VM + 30 MON (P<0,05). No Exp. 3, sessenta bovinos (Bos taurus) foram blocados e randomizado pelo peso corporal, com seis tratamentos e dez repetições. Os tratamentos foram grãos de milho seco e laminados reconstituídos com água até atingirem o teor de umidade de 27 (HMC27%), 30 (HMC30%), 33 (HMC33%), 36% (HMC36%) e em seguida foram ensilados por 101 dias previamente ao início do experimento. Milho floculado e milho laminado seco também foram utilizados como tratamento. Não foi observada diferenças no desempenho (P<0,05) dos animais confinados por 89 dias. Paralelamente foi conduzido um experimento in vitro para avaliar a produção de gás dos milhos processados. O uso de HMC na dieta de bovinos confinados não melhorou o desempenho dos animais. Já quando os milhos processados foram avaliados in vitro, maior teor de umidade resultou em maior fermentação e consequentemente maior produção de gás.
20

Controle biológico de Botrytis cinerea em pós-colheita de morango (Fragaria x ananassa) por linhagem Streptomyces araujoniae sp. nov. / Biological control of Botrytis cinerea on post-harvest strawberry (Fragaria x ananassa) by Streptomyces araujoniae sp. nov.

Silva, Leonardo José da 29 January 2014 (has links)
A produção brasileira de alimentos cresce em ritmo vertiginoso, havendo previsão de expansão nos próximos anos. Nota-se, porém, que o modelo atual empregado ao controle de doenças e pragas agrícolas, tem causado diversos problemas de ordem ambiental, social e econômica. Uma alternativa à redução de tais impactos, tem sido a implementação do controle biológico no modelo de manejo. Neste trabalho, avaliou-se o controle biológico do fungo fitopatogênico Botrytis cinerea por compostos produzidos pela linhagem ASBV-1T. Os screenings \"in vitro\" demonstraram que a linhagem produz quitinases e metabólitos secundários ativos, conhecidamente descritos como fatores importantes ao controle de fitopatógenos. A caracterização parcial do complexo enzimático, indicou que as quitinases produzidas pela linhagem ASBV-1T apresentam maior atividade em meio alcalino (pH 6.8-10.0), temperatura de 30°C e possuem estimativa de peso molecular superior a 100 kDa. Os ensaios \"in vivo\", realizados em morangos comerciais (cv. Oso Grande) demonstraram a efetividade dos subprodutos bioativos de caráter ionóforos (monactina, dinactina, trinactina, tetranactina e valinomicina) em controlar a infestação de B. cinerea, durante a fase de pós-colheita, em condições de armazenamento. Por meio da suplementação do meio de cultivo por sais inorgânicos, a via biossintética responsável pela expressão dos compostos de interesse pode ser ativada. A adição de MgS04 resultou em um aumento de 400% na produção de macrotetralídeos e 20% de valinomicina. Contudo, a expressão dos macrotetralídeos foi completamente inibida pela adição de ZnSO4. dobrando a produção de valinomicina. De acordo com os estudos de taxonomia polifasica, o isolado ASBV-1T, apresenta caracteristicas quimiotaxonômicos e moleculares pertinentes ao gênero Streptomyces, formando uma nova linha filética, no subclado das espécies S. albolongus, S. cavourensis subsp. cavourensis e S. celluloflavus. Diante do supra citado, propõem-se que o isolado seja reconhecido como a linhagem tipo de Streptomyces araujoniae sp. nov. Os resultados obtidos neste trabalho, permitem afirmar que a linhagem S. araujoniae sp. nov. apresenta potencial de ação contra o fitopatógeno B. cinerea, podendo auxiliar no controle desta doença durante a fase de pós-colheita da cultura de morangos. Ainda resta, para estudos futuros, o desenvolvimento de formulação específica para o emprego destes compostos no manejo da cultura, bem como ensaios toxicológicos, assegurando a viabilidade de aplicação de tais compostos. / The Brazilian food production has been growing fast in recent years and is expected to expand even more. However, the models used for the control of pests and diseases in agriculture has been widely questioned because they cause problems of environmental, social and economic. To reducing the use of chemical agents, has been the implementation of biological control to the management model to reduce this problematic. In this study, we evaluated the biological control of fungal pathogen Botrytis cinera of active compounds produced by strain ASBV-1T. In vitro assays indicated the presence of chitinase and antifungal metabolites in compounds produced by strain ASBV-1T and may been contributed to the antagonistic activity againts the fungal pathogenic. Partial characterization of the enzymatic complex showed the highest production of chitinase under alkalines conditions at pH (6.8-10.0), 30°C and has estimated molecular weight above 100 kDa. The test in vivo, preformed in commercial strawberries (cv. Oso Grande) demonstrated the effectiveness of bioactive products of character ionophores (monoactin, dinactin, trinactin, tetranactin and valinomycin) controlling the infestation of B. cinerea during the post-harvest, in store conditions. The biosynthetic pathway responsible for the expression of the compounds of interest can be activated by supplementations of the culture medium by inorganic salts mainly with MgSO4 resulted in increse of 400% in the production of macrotetralides and 20% valinomycin. However, the expression of the macrotetralides was inhibited when added ZnSO4, bending the production of valinomycin. According to polyphasic taxonomic studies, the isolated ASBV-1T has chemotaxonomic and molecular characteristics of the genus Streptomyces, which formed a new phyletic line, in subcalde of the S. albolongus, S. cavourensis subsp. cavourensis e S. celluloflavus species. Then propose that the isolate is recognized as the type strain of Streptomyces araujoniae sp. nov. The results obtained in this study revealed that S. araujoniae sp. nov. has action potential against the pathogen B. cinerea, can help control this disease during the post-harvest strawberries. Remains for future studies, the development of specific formulation of the employment of such compounds to crop management and toxicological tests, ensuring the feasibility of using such compounds.

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