998 resultados para CERRADO
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The high demands for sugars and the development of enzymatic technology have increased the production of sweeteners, especially for glucose and fructose syrups. This work describe a technology for glucose and fructose syrups from Brazilian cassava starch using enzymes produced by soil microrganisms isolated from the Brazilian Cerrado soil. Firstly, Aspergillus niger and Streptomyces sp. were isolated from the soil and used as glucoamylase (GA) and glucose isomerase (GI) producer sources. After characterization, GA and GI exhibited optimum pH 4.5 and 8.0, respectively. GA showed maximum activity at 60 ºC and GI at 85 ºC. GA and GI retained 65 and 80%, respectively, of initial activity after 180 minutes of incubation at 60 ºC. The kinetic parameters Km and Vmáx were 0.476 (mg.mL-1) and 8.58 (µmol/minute) for GA and 0.082 (M) and 48.20 (µmol/minute) for GI. The maximum glucose syrups production occurred after 24 hours of reaction with a 98% yield. The production of fructose syrups with 42% (w/v) was reached after 96 hours of reaction.
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Annona crassiflora (araticum), Eugenia dysenterica (cagaita), and Caryocar brasiliense (pequi) are tropical fruits of the second biggest Brazilian biome: the cerrado. Nowadays, the cerrado faces two different realities: 1) the great possibility of food production since it is considered as the biggest storehouse of the world; and 2) the rich biodiversity that has been newly discovered and known. Previous studies showed that certain cerrado fruits demonstrate high content of total phenols and excellent antioxidant activity in in vitro models. Moreover, using fingerprinting analysis, important bioactive molecules were identified as probably responsible for their antioxidant activity. In this study, the cytotoxicity and phototocixity of ethanolic extracts from cerrado fruits were evaluated using the in vitro Neutral Red Uptake (NRU). Regarding cytotoxicity, the extracts of araticum peel and cagaita seed did not shown any cytotoxic potential up to 300 µg.mL-1. Ethanolic extracts of araticum seed and pequi peel presented low cytotoxic potential and, according to linear regressions, the estimated LD50 were de 831.6 and 2840.7 mg.kg-1, respectively. In the evaluated conditions, only the araticum peel extract presented a phototoxic potential. This is the first attempt to screen the toxicity of cerrado fruits with high antioxidant activity.
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Based on the concept that the trellising system affects not only sunlight interception and carbon assimilation, but also the fruitzone microclimate, which has a great impact on fruit composition and consequently on wine quality, the effect of two trellising systems - Vertical Shoot Position (VSP) and modified Geneva Double Curtain (GDC) - on wine and berry composition of Syrah grapes grown in João Pinheiro, Northeast region of Minas Gerais State, Brazil was investigated. The parameters such as pH, berry size and weight, and seeds total phenolic contents were not affected by the training system. The GDC system produced fruits with the highest Brix and lowest titratable acidity. Berries from the VSP system presented lower anthocyanin concentration than those from the GDC system. Similar results were found for the total phenolic content of the skin of grape berries from the VSP system. GDC wines were characterized by high anthocyanin content and red color, resulting in wines with high color intensity. These data suggest that in the tropical region of Minas Gerais state, with high temperature and high sunlight intensity, the trellising system, which protects bunches against excessive radiation, should be chosen.
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Artemia salina bioassay was used to assess toxicity of seeds and kernels of Brazilian fruits from cerrado (central high plains region) and other inner regions of the country. Water extracts of the kernels were filtered and added to Artemia cultures containing ten individuals per mL. Dose - response curves were constructed, and LD50 values were calculated. Pure potassium cyanide standard was used to draw a calibration curve for comparison to detect the presence of cyanide in the samples tested. Extracts of the seeds of araticum, mangaba, cagaita, jatobá, and tucumã were found toxic to Artemia salina, and some of the dose - response curves were very similar in shape to those obtained with pure potassium cyanide standards, while the samples of baru, cajá-manga, siriguela, trauma, and veludo showed no toxicity at all. The Guignard test, specific for cyanide detection, showed negative results in all toxic samples, suggesting the presence of other toxic compounds rather than cyanide. The comparison of araticum dose - response curve with those of other annonaceous fruits suggests the presence acetogenins as the main toxic compounds in the seeds. These results could be useful to prevent poisoning by industrial derivatives of the fruits studied.
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The Brazilian Savannah, known as "Cerrado," has an extensive biodiversity, but it is under explored. Among the native vegetables is the jatobá-do-cerrado (Hymenaea stigonocarpa Mart.), a legume with great potential for exploration for its content of dietary fiber. Legumes are an important source of nutrient compounds, such as phenolic compounds and vitamins that have antioxidant properties. This study aimed at determining the chemical composition and antioxidant activity of the jatobá flour. The jatobá flour showed high fiber content (insoluble and soluble fiber 47.8 and 12.8 g.100 g- 1, respectively), significant amounts of carotenoids such as beta-carotene and lutein, and some minerals such as calcium: 145 mg.100 g- 1, magnesium: 125 mg.100 g- 1, and potassium: 1352 mg.100 g- 1. The jatobá flour extracted with different solvents (water, methanol, and acetone) exhibited antioxidant activity by the DPPH, FRAP, and ORAC methods. The solvent used in the extraction affected the total phenolic content and antioxidant activity. Acetone extraction produced the best results. Therefore, the jatobá flour is an ingredient that can be used to develop new products with properties that promote health.
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The objective of this study was to characterize the development of pequi fruit (Caryocar brasiliense) of the Brazilian cerrado. It takes 84 days (12 weeks) for pequi to develop with the onset of flowering in September and early fruit set in January. Pequi fruit showed a simple sigmoid growth curve, and its growth was characterized based on fresh mass and longitudinal and transverse diameters. The contents of titratable acidity, soluble solids, β-carotene, and vitamin C increased during fruit growth, reaching their maximum values at the 12th week (84 days) after anthesis. Pequi is a fruit with an extremely high respiratory activity; its respiratory rate decreased during its development. Pequi fruit has been classified as a non-climacteric fruit due to the decrease of both respiration and ethylene production rates during maturation and ripening.
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Abstract Oxygen metabolism in cells causes the production of free radicals, which produce damage, including changes in cell structure and function. Antioxidants are substances that, at low concentrations, slow down or prevent oxidation. Fruits and vegetables contribute to the dietary supply of these compounds. The flora of the Cerrado in Brazil has shown to have high levels of bioactive compounds. This study aimed to characterize the antioxidant activity of the pulp of jatobá-do-cerrado in vitro and in vivo.In vitro antioxidant activity of the aqueous, ethanol and aqueous acetone extracts was evaluated by the DPPH method. We determined total phenols by the Folin-Ciocalteu assay and tannins by the Folin-Denis method.In vivo antioxidant potential of the aqueous acetone extract was evaluated by the TBARS technique. The aqueous acetone extract had the highest antioxidant capacity, followed by the aqueous and ethanol extracts. The same pattern occurred in the extraction of phenols and in the extraction of tannins. In vivo administration of the aqueous acetone extract inhibited lipid peroxidation compared to the control group. The inhibition of peroxidation has increased by elevating the dosage concentration of the extracts, demonstrating a significant antioxidant potential in vivo as well as in vitro.
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Neste estudo foi descrito a biometria de frutos e de sementes de uma população de Hymenaea stigonocarpa var. stigonocarpa foi avaliado o efeito da massa de sementes na proporção e no tempo de germinação, sob condições de laboratório (câmara de germinação) e em viveiro, considerando como critérios de germinação a protrusão da raiz primária e a expansão de eófilos. Esta população de jatobá-do-cerrado apresentou uma grande variação no tamanho de frutos e de sementes. A massa das sementes variou entre 0,546 e 7,666 g e estas foram classificadas em pequenas, médias e grandes. Uma proporção maior de sementes classificadas como médias, emitiu a raiz primária em relação às grandes, enquanto as pequenas ocuparam posição intermediária. A massa de sementes não influencia a proporção de sementes que apresenta expansão de eófilos. As sementes grandes emitem a raiz primária mais rapidamente que as pequenas. O tempo médio da expansão de eófilos decresce com a redução da massa de sementes. Apesar das sementes médias e pequenas possuírem maior potencial para expor a raiz primária, estas apresentam maior taxa de mortalidade na transição entre as fases de protrusão da raiz primária e de expansão de eófilos.
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Teis ( Maestro en Ciencias de la Ingeniería Eléctrica con Especialidad en Potencia) - U.A.N.L, 2002
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Tesis (Maestría en Ciencias de la Ingeniería Eléctrica con Orientación en Control Automático) UANL, 2012.
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Tesis (Doctor en Ciencias con Acentuación en Manejo de Vida Silvestre y Desarrollo Sustentable.) UANL, 2009.
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Entender los mecanismos sociales que posibilitan la educación para la salud, conceptualizando la manera de enfermar y de curar, para transformar la realidad. Definir el concepto de salud y de educación sanitaria. Diseñar un programa de educación sanitaria. Analizar el marco institucional dónde se desarrolla el proyecto. 1 grupo-clase de 31 alumnos de segundo grado de EGB (entre 7 y 8 años), seis de ellos integrantes de la clase de Educación Especial. Centro situado en el barrio de Horta, en Barcelona. Realiza un estudio sobre los déficits de cada niño en el area de la educación santitaria y prevención sanitaria. Se propone concienciar también el grupo de maestros en este tema, para que se fomente la estima y el respeto para el propio cuerpo y el de los demás a lo largo de la escolaridad en el centro. Realiza un análisis comparativo entre la teoria médico-pedagógica y la propia praxis en educación. Realiza una encuesta y un análisis de la misma. Emplea un cuento para prevenir la adicción a la nicotina llamado La bruixa Nicotina (La bruja Nicotina). La encuesta consta de 36 preguntas cerradas, con dos ítems posibles. El análisis de las preguntas consta de dos bloques temáticos:a) Las que hacen referencia a la educación sobre las drogas, los hábitos higiénicos, la educación dietética, la educación física, la educación en el tiempo libre, la educación ecológica y la educación sexual. Los resultados de las encuestas demuestra cómo aspectos positivos: que los niños comen solos, les gusta la fruta, tienen el hábito de lavarse los dientes bastante arraigado, se lavan las manos, les gusta leer, etc. Destaca cómo aspectos negativos acostumbran a beber refrescos para cenar, no les gusta la verdura, etc. El alumnado acoge con atención la narración del cuento, demuestra mediante dibujos que se adjunta a la memoria y que ha asimilado e interiorizado los conceptos implícitos y explícitos. Sin pretender hacer un análisis exhaustivo y general de la educación para la salud, el programa de educación para la salud aquí expuesto se adapta adecuadamente a las características de todos los alumnos del centro, debido a la contextualizcaión que se ha realizado previamente. Se propone que la educación para la salud se interiorice en la praxis de los educadores ofreciendo pautas, hábitos y puntos de referencia claros y coherentes para el alumnado.
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Resumen basado en el de la publicaci??n
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Indagar las bases sociológicas, empíricas y teóricas de la formación del profesorado mediante el CCTV así como los factores determinantes de un proceso eficaz de entrenamiento. Crear un método de formación continua del profesorado centrado en la acción docente, siguiendo el modelo de la supervisión clínica y el proceso exigido por el CCTV. Los modelos de formación continua del profesorado agrupados en modelos tecnológicos y modelos humanistas. El proceso de entrenamiento empleando el vídeo como auxiliar de este entrenamiento. Diseño descriptivo. Modelos de formación continua del profesorado, que empleen o puedan emplear el vídeo, divididos en dos grupos: modelos tecnológicos y modelos humanistas. Estructura del proceso enseñanza aprendizaje en el que se estudian las variables: de presagio, del proceso, del producto y del contexto, con el fin de valorar la eficacia de este proceso. Estructura del proceso de entrenamiento estudiando el empleo del vídeo como variable independiente y los resultados obtenidos en la formación continua del profesorado como variable dependiente. Véase bibliografía. Análisis crítico de los distintos modelos de formación continua del profesorado que empleen o puedan emplear el vídeo en sus dos modalidades: para la heteroobservación y para la autoobservación. Análisis crítico e histórico de las tendencias actuales en la formación continua del profesorado. Análisis comparativo entre distintos paises sobre lo legislado y realizado en la formación continua del profesorado. Análisis histórico y empírico de los elementos determinantes de la eficacia en el proceso enseñanza aprendizaje. Análisis crítico del proceso de entrenamiento empleando el vídeo como auxiliar de este entrenamiento. La formación contínua del profesorado tiende a llevarse a cabo en el lugar de trabajo y a centrarse en las tareas docentes normales. El empleo del vídeo contribuye eficazmente al proceso de perfeccionamiento. Tanto en los modelos tecnológicos como humanistas de formación continua del profesorado el vídeo es un auxiliar utilizado. Elaboración de un método de formación continua del profesorado basado en el modelo de supervisión clínica y el empleo del vídeo como auxiliar del proceso centrado en un tipo de profesor universitario encargado de dar clases teóricas. Las variables del proceso de entrenamiento son tan complejas y sus interrelaciones aun más complejas por lo que hay que estar siempre atento y abierto a las nuevas aportaciones de la ciencia tanto en el campo empírico como en el teórico. Es preciso una sólida preparación y una larga experiencia para garantizar el empleo adecuado del vídeo tanto en la formación inicial como en la formación continua del profesorado.
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Recoge experiencias sobre la formación del profesorado, grabadas con circuito cerrado de televisión, con la finalidad de analizarlas y perfeccionarlas.