207 resultados para Goma guar


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O lobo-guará é uma espécie de ampla distribuição na América do Sul, tendo no Brasil sua maior área de ocorrência. No entanto, as modificações das áreas naturais principalmente destinadas à agropecuária tornam a espécie vulnerável à extinção. A investigação objetivou conhecer em larga escala a área de distribuição potencial gerada por atributos ambientais favoráveis e áreas adequadas à sua ocorrência nos biomas brasileiros e investigar como a espécie responde à estrutura da paisagem, avaliando os efeitos de ambientes modificados pelo homem na sua ecologia espacial, nos padrões de atividade e na movimentação. Modelos de distribuição de espécie foram gerados pelo Maxent, utilizando uma base de pontos de localização de presença a partir de 2000 para o Cerrado (Ce), Pantanal (Pa), Mata Atlântica (MA) e Pampas (Pp) e um conjunto de onze variáveis ambientais não correlacionadas (topográficas, climáticas e paisagísticas). Para análises de ecologia espacial, das atividades e de movimentação, utilizou-se localizações de telemetria (GPS) de animais habitantes de áreas protegidas (AP), e indivíduos em paisagens modificados (AM). Análises de áreas de vida (AV) foram realizadas utilizando o estimador AKDE e associadas com classificação da paisagem local. Os modelos de distribuição do lobo-guará apresentaram uma área de distribuição potencial de 78% do total dos biomas. Apesar de possuírem grandes proporções de áreas adequadas (Ce, 90%; Pa, 93%; MA, 65% e Pp, 6%), somente um pequeno percentual (4,4% do Ce e 4,7% da MA) possui adequabilidade ambiental acima de 50%. Dos atributos que favorecem sua presença, a altitude (para todos os biomas), a precipitação (Ce e Pa), diferenças de temperatura e uso e cobertura do solo (Ma e Pp) foram os mais importantes. Em nível local, animais apresentaram média de AV de 90Km2 em AP e 41Km2 em AM, uma diferença significativa (p<0,01) com áreas diretamente proporcionais ao percentual de áreas naturais na paisagem. Ainda, apesar dos padrões regulares de atividade não mostrarem grandes mudanças, o período de repouso foi significativamente maior (p<0,01) entre os animais AM (46% do dia) que em animais AP (25% do dia). Lobos-guarás de AP e AM não apresentaram grandes diferenças no deslocamento diário com média geral de 14km caminhados por dia, com comprimentos de passos de 1Km. Diferenças no comprimento de passo foram relacionadas à composição da diversidade de contato de classes da paisagem com a proporção de ambientes naturais no passo (quanto maior as variáveis, maior o passo). Passos menores refletem menor persistência de movimento interferindo no deslocamento diário. Com os resultados desse estudo identificou-se a MA e Pa muito importantes, mas o Ce como bioma mais adequado à espécie. Foram encontrados indícios de que a estrutura de suas AV, o uso da paisagem, as atividades e movimentação são afetados pela paisagem modificada. Isso pode comprometer a viabilidade populacional, interferindo na presença em uma área e refletindo no seu potencial de distribuição. As estratégias de manejo de uso do solo, e a recuperação e conexão de áreas adequadas são urgentes e necessárias para que o lobo-guará permaneça presente e funcional nas paisagens dos biomas brasileiros.

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At head of title: Oficina Nacional de Inmigracion, Estadística y Propaganda Geográfica.

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In double columns.

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Mode of access: Internet.

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The written text, and approaches to reading it, serves well as an analogy for the classroom space as a "text" that teachers are able to compose; and students are able to read, interpret meaning(s) of, and make responses to and about (Rosenblatt, 1988). Researchers point to ways in which the classroom can be conceptualized as a text to be evoked, experienced, and read (Freire & Macedo, 1987; Powell, 2009; Rosenblatt, 1988; Spears-Bunton & Powell, 2009).^ The present study analyzed secondary data including: 10 transcripts of teacher talks and six self-reports retrieved from the program evaluation archives of DOR Foundation. The data described six teachers' classroom experiences subsequent to professional development centered on Goma character education curriculum that was used during a summer youth program located in South Georgia. Goma, an acronym that stands for Goal, Objective, Method, and Attitude, is a character education paradigm derived from The Inclusive Community Building Ellison Model, the theoretical framework used for this study. The Model identifies conflict resolution as one of its five foci (Hunt, Howard, & Rice, 1998). Hunt (2006) conceived Goma as part of a 7-Step unitary process, also named the 7-Step pathway, to demonstrate how conflict resolution is accomplished within a variety of contexts.^ Analysis of the data involved: (a) a priori coding of teacher talks transcripts using the components of the Goma 7-Step pathway as coding categories, (b) emergent coding of teacher talks transcripts for the types of experiences teachers evidenced, and (c) emergent coding of teachers' self-reports for categories of teachers' instructional activities. Results of the study showed positive influence of Goma curriculum on participating teachers and their instructional practices. Teachers were shown to have had cognitive, instructional, emotional, and social experiences that were most evident when they reported changes in their attitudes toward their students, themselves, and their instructional practices. The present study provided implications for classroom teachers wherein all aspects of teachers' instructional practices can be guided by principles of positive character; and can be used to help compose the kinds of "texts" that may likely contribute to a classroom character culture.^

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This study aimed mainly to evaluate the influence of xanthan gum (XG) and carboxymethylcellulose (CMC) in the filtration process of water-based drilling fluids, considering the conformational changes suffered by the polyelectrolyte with the addition of sodium chloride (NaCl) in different concentrations (0.17, 0.34 and 0.51 mol.L-1). It was also evaluated the behavior of the fluid by the addition of calcium carbonate (CaCO3) in pure water and in brine. Seeking a better understanding of the interaction between the polymers used and CaCO3, polymer adsorption analyzes were performed using a depletion method, which yielded a higher percentage of adsorption of Xanthan Gum in this material (29%), which can justify the formation of a thin and waterproof filter cake for drilling fluids containing this polymer. However, the best values of apparent viscosity (20 and 24 mPa.s) and volume of filtrate (8.0 and 8.1 mL) were obtained for the systems consisting of xanthan gum, CMC and CaCO3, in NaCl aqueous solutions concentrations of 0.34 and 0.51 mol.L-1, respectively. The values can be related to the presence of CMC that increases the apparent viscosity and reduces the volume of filtrate. In addition, the CaCO3 added acts as a bridging agent, promoting the formation of a less permeable filter cake

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CHAPTER II - The Chrysocyon brachyurus is the biggest South American canid which has a high frequency of dental injuries, both in wild and captivity. Thus, veterinary procedures are necessary to preserve the feeding capacity of hundreds of captive specimens worldwide. The aim of this study was to study the mandibular morphometry of maned wolf with emphasis on the establishment of anatomic references to the anesthetic blockage of the inferior alveolar and mental nerves. Therefore, 15 measurements in 22 hemimandibles of C. brachyurus adults were taken. For extra-oral technique of blockage of the inferior alveolar nerve at the level of the mandibular foramen, it is stated that the needle should be advanced, close to the medial surface of the mandibular ramus, by 11.4 mm perpendiculary from the palpable concavity. Alternatively, the needle can be introduced for 30.4 mm from the angular process at 20-25 degrees angle with the ventral margin. For blocking only the mentual nerve, it is recommended the introduction of needle for 10 mm, close to the lateral aspect of the mandibular body, at the level of the lower first premolar. The mandibular foramen showed similars position, size and symmetry in the maned wolfs specimens examined. The comparison of the data with those available for other carnivores reflects the necessity for determining these anatomical references specifically for each species.

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Oral route of administration is considered to be the most comfortable, safe and greater adaptation for patients. But, oral route presents some disadvantages such as drugs bioavailability and side effects on the stomach. Some technologies are studied to soften and/or resolve these problems, such as coating with polymeric films, which are able to protect the pharmaceutical form of the acid stomachic environment and to act in the drug release, and mucoadhesive systems, which allow the pharmaceutical form remains a greater time interval in the intestine, increasing the effectiveness of the drug. Cellulose triacetate (CTA) films were produced from cellulose extracted from sugar cane bagasse. The films were prepared with different morphologies (with and without water, acting as non-solvent) and concentrations (3, 6.5 and 10%) of CTA and characterized using scanning electron microscopy (SEM), water vapor permeability (WVP), puncture resistance (PR), enzymatic digestion (DE), and mucoadhesive force evaluation (MF). Microscopy showed the formation of symmetric and asymmetric morphologies. WVP data showed that more concentrated films have higher values for WVP; moreover, asymmetric films had higher values than symmetric films. PR measurements showed that symmetric membranes are more resistant than asymmetric ones. More concentrated films were also more puncture resistant, except for symmetric membranes with CTA concentrations of 6.5 and 10% that did not show significant differences. All of the films presented large mucoadhesive capacities independent of their morphology and CTA concentration. From the results of WVP and RP, a symmetric filme with 6.5% CTA showed better ability and mechanical resistance, therefore, was selected to serve as coating of gellan gum (GG) particles incorporating ketoprofen (KET), which was confirmed by SEM. The selected film presented low values in measurements of the swelling index (SI) and in a dissolution test (DT). TGA analysis showed that the CTA coating does not influence the thermal stability of the particles and there is no incompatibility evidence between CTA, GG and KET. Coated particles released 100% of the ketoprofen in 24 h, while uncoated particles released the same amount in 4 h. The results of this study highlight the potential of CTA in the development of new controlled oral delivery systems.

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The individual and interactive impacts of guar gum and glycerol on the pea starch-based edible film characteristics were examined using three factors with three level Box–Behnken response surface design. The results showed that density and elongation at break were only significantly (p < 0.05) affected by pea starch and guar gum in a positive linear fashion. The quadratic regression coefficient of pea starch showed a significant effect (p < 0.05) on thickness, density, puncture force, water vapour permeability, and tensile strength. While tensile strength and Young modulus affected by the quadratic regression coefficient of glycerol and guar gum, respectively. The results were analysed using Pareto analysis of variance (ANOVA) and the developed predictive equations for each response variable presented reliable and satisfactory fit with high coefficient of determination (R2) values (≥ 0.96). The optimized conditions with the goal of maximizing mechanical properties and minimizing water vapour permeability were 2.5 g pea starch, 0.3 g guar gum and 25 % (w/w) glycerol based on the dry film matter in 100 ml of distilled water. Generally, changes in the concentrations of pea starch, guar gum and glycerol resulted in changes in the functional properties of film.

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The written text, and approaches to reading it, serves well as an analogy for the classroom space as a “text” that teachers are able to compose; and students are able to read, interpret meaning(s) of, and make responses to and about (Rosenblatt, 1988). Researchers point to ways in which the classroom can be conceptualized as a text to be evoked, experienced, and read (Freire & Macedo, 1987; Powell, 2009; Rosenblatt, 1988; Spears-Bunton & Powell, 2009). The present study analyzed secondary data including: 10 transcripts of teacher talks and six self-reports retrieved from the program evaluation archives of DOR Foundation. The data described six teachers’ classroom experiences subsequent to professional development centered on Goma character education curriculum that was used during a summer youth program located in South Georgia. Goma, an acronym that stands for Goal, Objective, Method, and Attitude, is a character education paradigm derived from The Inclusive Community Building Ellison Model, the theoretical framework used for this study. The Model identifies conflict resolution as one of its five foci (Hunt, Howard, & Rice, 1998). Hunt (2006) conceived Goma as part of a 7-Step unitary process, also named the 7-Step pathway, to demonstrate how conflict resolution is accomplished within a variety of contexts. Analysis of the data involved: (a) a priori coding of teacher talks transcripts using the components of the Goma 7-Step pathway as coding categories, (b) emergent coding of teacher talks transcripts for the types of experiences teachers evidenced, and (c) emergent coding of teachers’ self-reports for categories of teachers’ instructional activities. Results of the study showed positive influence of Goma curriculum on participating teachers and their instructional practices. Teachers were shown to have had cognitive, instructional, emotional, and social experiences that were most evident when they reported changes in their attitudes toward their students, themselves, and their instructional practices. The present study provided implications for classroom teachers wherein all aspects of teachers’ instructional practices can be guided by principles of positive character; and can be used to help compose the kinds of “texts” that may likely contribute to a classroom character culture.