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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.
71

Coca y wachuma:sus prácticas y significados en la cultura andina y en Lima

Feldman Gracia, Leonardo January 2011 (has links)
La primera parte de la tesis no implica trabajo de campo, sino que toma como base fuentes antropológicas, documentos coloniales y evidencias arqueológicas de uso de estas plantas en el pasado prehispánico. A partir de esta documentación, se realiza un análisis comparativo de la coca y el wachuma, considerando 4 aspectos principales: (1) caracterización de ambas plantas maestras (botánica, especies y variedades, contenido en alcaloides y nutrientes, efectos sicotrópicos); (2) la historia “arqueológica” (origen y domesticación, historia prehispánica); (3) las fuentes escritas de los siglos XVI y XVII; (4) el uso tradicional (áreas y contextos de uso, los especialistas). El capítulo 2 está referido a la coca y el capítulo 3 al wachuma, en cada caso se considera los cuatro aspectos arriba especificados. En el capítulo 4 se presenta un estudio comparativo del hallpay -rito de coca- y de la mesada -rito de wachuma-, donde se cotejan las formas y los contenidos de ambos ritos. En el capítulo 5 se resumen las analogías y diferencias en las prácticas y significados de la coca y del wachuma en la cultura andina. El aporte primordial de esta tesis se refiere a los nuevos usos y significados que tienen la coca y el wachuma durante los recientes años, en la ciudad de Lima. No hay ningún estudio antropológico sistemático sobre este tema. Por ello, para obtener las respuestas buscadas, ha sido necesaria la indagación etnográfica a través del trabajo de campo.
72

Efecto hepatoprotector del zumo del fruto de Corryocactus brevistylus (Sanky) en ratones con daño hepático inducido por etanol

Lipe Camero, Carolina Rocio January 2016 (has links)
Determina el efecto hepatoprotector del zumo del fruto de Corryocactus brevistylus (Sanky) en ratones con daño hepático inducido por etanol. Utiliza las instalaciones del Centro de Investigación de Bioquímica y Nutrición Alberto Guzmán Barrón de la Facultad de Medicina de la Universidad Nacional Mayor de San Marcos. Realiza un estudio analítico, transversal, prospectivo y experimental. Emplea una muestra de 56 ratones albinos, machos, adultos, y zumo del fruto de Corryocactus brevistylus (Sanky). El fruto del sanky fue recogido del distrito de Puquina, provincia General Sánchez Cerro, región de Moquegua, en el mes de julio de 2015. Los ratones son distribuidos aleatoriamente en 7 grupos (n=8) a los que se les administra por 5 días: (G-I) Suero fisiológico + agua ad libitum; (G-II) Suero fisiológico + etanol al 5% ad libitum; (G-III) Silimarina + etanol al 5% ad libitum; (G-IV) 1mL de zumo de sanky + etanol al 5% ad libitum; (G-V) 1mL de zumo de sanky + agua ad libitum; (G-VI) 10mL de zumo de sanky + etanol al 5% ad libitum; (G-VII) 10mL de zumo de sanky + agua ad libitum. Las medidas de los resultados son el nivel de lipoperoxidación expresado en sustancias reactivas al ácido tiobarbitúrico (TBARs), y nivel de grupos sulfidrilos no proteicos (GS-NP); además se evalúa la hepatomegalia mediante el cálculo del Índice Hepático (IH). Encuentra que la hepatomegalia es mayor en el G-II (6,37±0,69 %), mientras que en los grupos de tratamiento se obtuvo una reducción no significativa. Se observa una reducción del porcentaje de lesión por los niveles de TBARs, en los grupos tratamiento V y VII (-19,7 y -19,24 % respectivamente). Los mayores niveles de GS-NP se presentan en los grupos tratamiento V y VI (4392,43 ± 354,04 y 4897,26 ± 796,09 μg/mL/g de tejido, respectivamente). Concluye que la administración del zumo del fruto de Corryocactus brevistylus (sanky) en ratones con daño hepático inducido por etanol presenta efecto hepatoprotector a nivel de GS-NP.
73

Evaluación de la capacidad antioxidante y efecto hepatoprotector del zumo del fruto corryocactus brevistylus, en ratas con intoxicación por paracetamol

Huamán Gutiérrez, Oscar Gustavo January 2019 (has links)
Analiza la capacidad antioxidante y el efecto del zumo del fruto Corryocactus brevistylus (sanky) en el hígado frente a la toxicidad por paracetamol en ratas. Se empleó el zumo y el sobrenadante del zumo del fruto de sanky y 48 ratas machos. La actividad antioxidante del zumo y del sobrenadante del zumo fueron evaluados por la capacidad de reducir al radical DPPH e inhibir la lipoperoxidación en homogenizado de tejido hepático frente al sistema H2O2/FeSO4. Para la evaluación de hepatoprotección los animales fueron distribuidas aleatoriamente en seis grupos (n=8), recibiendo los siguientes tratamientos por 10 días, vía peroral: grupos I y II NaCl 0,9%, grupo III silimarina 100 mg/kg, grupo IV zumo 1 mL/kg, grupo V zumo 5 mL/kg y grupo VI zumo 10 mL/kg. A partir del sexto hasta el décimo día se administró paracetamol a 400 mg/kg (grupos II-VI). Terminado el tratamiento las ratas fueron sacrificadas, previa anestesia con vapor de éter dietílico, luego se realizó la punción cardiaca para la extracción de sangre y se procedió a extraer el hígado por medio de laparotomía. Del lóbulo mayor se seccionó dos porciones, uno fue conservado en formol y otra porción fue conservada a 4°C para el análisis bioquímico. Resultados: el zumo y sobrenadante del zumo presentaron capacidad antioxidante. La administración del zumo a diferentes dosis expresó una menor actividad de la AST, ALT y GGT, también mostró una menor concentración de bilirrubina directa y total, una mayor concentración de proteínas total y albumina sérica, sin embargo, mostró un incremento de la actividad de la fosfatasa alcalina y de lipoperoxidación (hígado y suero). El índice hepático fue menor y a nivel histológico presentó mejor conservación de las estructuras. El zumo del fruto del sanky presenta actividad antioxidante in vitro y efecto hepatoprotector en ratas con intoxicación hepática por paracetamol. / Tesis
74

Caracterização anatômica, química e ultraestrutural de espinhos secretores em duas espécies de Opuntioideae (Cactaceae).

Silva, Stefany Cristina de Melo January 2019 (has links)
Orientador: Tatiane Maria Rodrigues / Resumo: Nectários extraflorais (NEFs) são comuns e morfologicamente diversos em Cactaceae, podendo se apresentar como espinhos altamente modificados ou não, folhas escamiformes e regiões epidérmicas e corticais especializadas na base ou ao redor das aréolas. Contudo, pouco é conhecido sobre a natureza dos NEFs em cactos e, mesmo, há dúvidas se o exsudato pode ser qualificado como néctar. Nosso objetivo foi analisar a morfologia, anatomia e ultraestrutura dos espinhos secretores em Brasiliopuntia brasiliensis e Nopalea cochenillifera e a composição química da secreção. Espinhos secretores foram processados para análises aos microscópios de luz (campo claro e confocal) e eletrônicos de varredura e transmissão (convencional e citoquímica). A composição dos açúcares e de aminoácidos foi analisada por cromatografia líquida de alta performance (HPLC). Observações de campo mostraram que o exsudato acumulado no ápice dos espinhos é removido por formigas. Os aspectos ontogenéticos, estruturais e funcionais dos espinhos secretores se mostraram semelhantes nas duas espécies estudadas. Os espinhos secretores se originam a partir do meristema areolar, tendo início como pequenas protuberâncias formadas por protoderme e meristema fundamental. Espinhos na fase secretora apresentaram a) base dilatada preenchida por células pequenas com paredes pecto-celulósicas delgadas, citoplasma denso e núcleo volumoso; b) região mediana alongada composta por células fibriformes com paredes não-lignificadas; e c) ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Extrafloral nectaries (EFNs) are common and morphologically diverse in Cactaceae, and may be highly modified spines or not, scamiform leaves and specialized epidermal and cortical regions located at the base or around the areoles. However, little is known about the nature of EFNs in cacti, and even if the exudate can be qualified as nectar. We aimed to analyze the morphology, anatomy and ultrastructure of the secretory spines in Brasiliopuntia brasiliensis and Nopalea cochenillifera and the chemical composition of the secretion. Secretory spines were processed for light (bright field and confocal) and scanning and transmission (conventional and cytochemical) electron microscopy. The composition of sugars and amino acids was analyzed by high performance liquid chromatography (HPLC). Field observations have shown that the exudate accumulated at the apex of the spines is removed by ants. The ontogenetic, structural and functional aspects of the secretory spines were similar in both species. Secretory spines originate from the areolar meristem, beginning as small protuberances formed by protoderm and fundamental meristem. Spines in the secretory phase presented a) dilated base filled by small cells with thin pecto-cellulosic walls, dense cytoplasm and voluminous nucleus; b) elongated median region composed of fibriform cells with non-lignified walls; and c) apical portion tapered with fusiform cells with non-lignified walls. Vascular tissues are present in the basal region of the... (Complete abstract click electronic access below) / Mestre
75

Utilização de nutrientes e parâmetros de fermentação ruminal em ovinos recebendo dietas com altas proporções de palma forrageira (Opuntia ficus indica Mill) / Use of nutrients and parameters of ruminal fermentation in ovines receiving diets with high percent of spineless cactus (Opuntia ficus indica Mill.)

SANTOS, Alessandra Oliveira de Araújo dos 25 February 2008 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-03-17T15:11:52Z No. of bitstreams: 1 Alessandra Oliveira de Araujo dos Santos.pdf: 221810 bytes, checksum: 9c39f5a687813d4ac077ac03137183b1 (MD5) / Made available in DSpace on 2017-03-17T15:11:52Z (GMT). No. of bitstreams: 1 Alessandra Oliveira de Araujo dos Santos.pdf: 221810 bytes, checksum: 9c39f5a687813d4ac077ac03137183b1 (MD5) Previous issue date: 2008-02-25 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The experiment was driven with the objective to evaluating the effect of addition of effective fiber, non effective fiber or tannin to diets contends high percents of spineless cactus for ovines about bloat production, rumen general conditions, intake and, dry matter and nutrients digestibility and animals ingestive behavior. Four canullated wethers was used, with live weight around of 43,8  1,62 kg, distributed in Latin square (4x4). Each experimental period had duration of 20 days. Being 10 of adaptation to experimental diets and 10 to collect. The treatments consisted of a diet base composed by spineless cactus, corn and soybean meal (D1) and addition of effective fiber from tifton hay (D3), addition of non effective fiber of soy peel (D4) and addition of tannis to reduce the ruminal fermentation (D2). The dry and organic matter intake in kg/day,% of PV and in relation to the PV0,75, and crude protein, ether extract, total carbohydrathes and total nutrients digestive, expressed in kg/day, were not influenced by the treatments, presenting medium values of 1,21; 60,91;70,36; 2,75; 1,04; 2,43; 62,07; 0,14; 20,81; 0,90 and 0,79, respectively. To example of the intake, dry and organic matter digestibility, crude protein, ether extract and the nitrogen balance (Nretained/Nabsorpted) expressed in percentages, it was not influenced by theexperimental treatments presenting medium value of 69,73; 74,29; 67,59; 62,18 and 79,06%, respectively. The bloat dynamics occurrence was influenced by the addition of acid tannis presenting values of 1,25 mm for foam production and 1,9 mg/mL for biofilm production even so the division of the nitrogen in the flowing ruminal didn't obtain difference. The pH, the concentration of ammonia nitrogen and the total production of volatile fatty acids were influenced by the diets presenting larger production of acids (175,55 mol/mL) and smaller pH value (6,18) for the fluids of the ovines fed with soy peel and larger ammonia production (7,51 mg/100mL) for fed them with tifton hay. The time of feeding went equal to every animals, even so the time of rumination went larger for the animals than they received hay, presenting value of 375 min/dia. Diets with discharges proportions of spineless cactus cause bloat production in ovines, just influencing in the consumption and digestibility of FDN, however the addition of approximately 15% of food of digestibility slower ruminal than the palm, reduces that effect, besides increasing the time of rumination. / O experimento foi conduzido com o objetivo de avaliar o efeito da adição de fibra efetiva, fibra não efetiva ou tanino em dietas contendo altos percentuais de palma sobre a ocorrência de timpanismo, as condições gerais do rúmen, o consumo e a digestibilidade da matéria seca e dos nutrientes bem como sobre o comportamento ingestivo de ovinos. Foram utilizados quatro ovinos fistulados no rúmen, adultos, castrados com peso vivo médio de 43,8  1,62 kg, distribuídos em quadrado latino (4x4). Cada período experimental teve duração de 20 dias. Sendo 10 de adaptação às dietas experimentais e 10 de coletas. Os tratamentos consistiram de uma dieta base composta por palma forrageira, milho e farelo de soja (D1) e adição de fibra efetiva proveniente do feno de tifton (D3), adição de fibra não efetiva proveniente da casca de soja (D4) e adição de ácido tânico para reduzir a fermentação ruminal(D2). Os consumos de matéria seca e orgânica em kg/dia, % de PV e em relação ao PV0,75, e proteína bruta, extrato e téreo, carboidratos totais e nutrientes digestíveis totais, expressos em kg/dia, não foram influenciados pelos tratamentos, apresentando valores médios de 1,21;2,75; 60,91; 70,36; 1,04; 2,43; 62,07; 0,14; 20,81; 0,90 e 0,79 , respectivamente. A exemplo dos consumos, as digestibilidades da matéria seca e orgânica, da proteína bruta, do extratoetéreo e o balanço de nitrogênio (Nretido/Nabsorvido) expressos em porcentagens, não foram influenciados pelos tratamentos experimentais apresentando valor médio de 69,73; 74,29;67,59; 62,18 e 79,06%, respectivamente. A ocorrência de timpanismo foi influenciada pela adição de ácido tânico, apresentando valores de 1,25 mm para produção de espuma e 1,9 mg/mL para a produção de biofilme. Porém, o fracionamento do nitrogênio no fluido ruminal não obteve diferença. O pH, a concentração de nitrogênio amoniacal e a produção total de ácidos graxos voláteis foram influenciadas pelas dietas apresentando maior produção de ácidos (175,55 mol/mL) e menor valor de pH (6,18) para os fluidos dos ovinos alimentados com casca de soja e maior produção de amônia (7,51 mg/100mL) para os alimentados com feno de tifton. O tempo de alimentação foi igual para todos o animais, porém o tempo de ruminação foi maior para os animais que receberam feno, apresentando valor de 375 min/dia.Dietas com altas proporções de palma forrageira causam timpanismo em ovinos,influenciando apenas no consumo e digestibilidade da FDN, porém a adição de aproximadamente 15% de alimento de digestibilidade ruminal mais lenta do que a palma,reduz esse efeito, além de aumentar o tempo de ruminação.
76

Very Cost Effective Partitions in Graphs

Vasylieva, Inna 01 May 2013 (has links)
For a graph G=(V,E) and a set of vertices S, a vertex v in S is said to be very cost effective if it is adjacent to more vertices in V -S than in S. A bipartition pi={S, V- S} is called very cost effective if both S and V- S are very cost effective sets. Not all graphs have a very cost effective bipartition, for example, the complete graphs of odd order do not. We consider several families of graphs G, including Cartesian products and cacti graphs, to determine whether G has a very cost effective bipartition.
77

Investigation of Opuntia ficus-indica Mucilage Nanofiber Membrane Filtration for Water Systems

Muppaneni, Rasudha 11 March 2015 (has links)
This work investigates the fabrication, characterization and testing of Opuntia ficus-indica mucilage nanofibers to be utilized in water filtration systems. These mucilage nanofibers are formed using different polymers through a process called electrospinning. The polymers used to promote the formation of nanofibers are poly vinyl alcohol (PVA) and polystyrene (PS). The mucilage is a jelly like substance extracted from the pads of the cactus plant. It is a mixture of proteins, complex polysaccharides and monosaccharaides. It is an inexpensive, non-toxic, biodegradable and biocompatible material which is present in abundance. The mucilage extracted from the pads is mixed with acetic acid to form the mucilage solution. The mucilage solution is then mixed by volume with co-spinning polymers, PVA and PS. PVA is a synthetic polymer that is water-soluble, and this work considers two types of PVA differentiated based upon molecular weight, such as low molecular weight PVA and high molecular weight PVA. Polystyrene is a synthetic polymer extracted from a monomer styrene, and it is inexpensive, biodegradable, and abundant. The polystyrene, in its solid form, is further decomposed using a solvent called D-Limonene. D-Limonene is a biodegradable, non-toxic solvent formed from the citrus extract of orange peelings. The PVA and PS solutions are mixed in several different volume ratios with the mucilage solutions. These solutions were electrospun and consistent nanofibers were obtained using the low molecular weight PVA solutions and the polystyrene solutions. The fibers and polymeric solutions were characterized by scanning electron microscopy (SEM), contact angle measurements, viscosity, and FTIR. Resulting mucilage nanofiber membranes were characterized by atomic fluorescence spectrometry (AFS) filtration testing. In addition, a life cycle analysis using the SimaPro software was performed to understand the environmental impact of solutions used to fabricate the mucilage nanofiber membranes. Characterization results confirm the formation of PVA:mucilage and PS:mucilage nanofibers. Filtration testing of the nanofiber membranes indicates better performance with membranes formed by PS: mucilage solutions as compared to PVA: Mucilage solutions. Overall, this work has shown that natural materials, such as cactus mucilage, can be synthesized with polymeric solutions to form environmentally friendly water filters.
78

Polynômes, arbres bicolorés et cactus

Paquin, Nicolas 02 1900 (has links) (PDF)
Dans ce mémoire, nous allons nous intéresser aux graphes obtenus en considérant l'image inverse d'un polygone (en particulier d'un segment) dont les sommets sont les valeurs critiques d'un polynôme. Nous allons commencer par des rappels de notions préliminaires sur les polynômes complexes, la topologie algébrique et la théorie des espèces. Ensuite, nous allons voir le lien entre les arbres plans bicolorés et les polynômes de Shabat, qui sont des polynômes ayant au plus deux valeurs critiques, mis à part l'infini. Subséquemment, nous étudierons quelques notions portant sur les cactus. Finalement nous bouclerons le tout par une exploration, à l'aide du logiciel Maple, des concepts élaborés dans les chapitres précédents. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : point critique, valeur critique, revêtement, polynôme de Shabat, arbre plan bicoloré, cactus, constellation, fonction symétrique, espèce de structures, itération de Newton-Raphson.
79

The Mucilage of Opuntia Ficus Indica: A Natural, Sustainable, and Viable Water Treatment Technology for Use in Rural Mexico for Reducing Turbidity and Arsenic Contamination in Drinking Water

Young, Kevin Andrew 06 April 2006 (has links)
The use of natural environmentally benign agents in the treatment of drinking water is rapidly gaining interest due to their inherently renewable character and low toxicity. We show that the common Mexican cactus produces a gum-like substance, cactus mucilage, which shows excellent flocculating abilities and is an economically viable alternative for low-income communities. Cactus mucilage is a neutral mixture of approximately 55 high-molecular weight sugar residues composed basically of arabinose, galactose, rhamnose, xylose, and galacturonic acid. We show how this natural product was characterized for its use as a flocculating agent. Our results show the mucilage efficiency for reducing arsenic and particulates from drinking water as determined by light scattering, Atomic Absorption and Hydride Generation-Atomic Fluorescence Spectroscopy. Flocculation studies proved the mucilage to be a much faster flocculating agent when compared to Al2(SO4)3 with the efficiency increasing with mucilage concentration. Jar tests revealed that lower concentrations of mucilage provided the optimal effectiveness for supernatant clarity, an important factor in determining the potability of water. Initial filter results with the mucilage embedded in a silica matrix prove the feasibility of applying this technology as a method for heavy metal removal. This project provides fundamental, quantitative insights into the necessary and minimum requirements for natural flocculating agents that are innovative, environmentally benign, and cost-effective.
80

The saguaro tree-hole microenvironment in southern Arizona, I. Winter

Krizman, Richard Donald, 1931- January 1964 (has links)
No description available.

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