716 research outputs found
A Surgery Table with a Mouth Prop for Rodents
Laboratory animal research represents a remarkable source of information. Rodents are often used as an experimental model for studies in the medical field, showing several advantages. The access to the oral cavity allows one to examine it and to perform surgical restorative procedures. The application of topical substances on hard tissues and mucosa is also possible. Literature includes reports on mouth-opening systems for animals, but they are not available on the market. Therefore, researchers must improvise methods that allow access to the oral cavity, but which may compromise the experiment. The purpose of this technical report is to introduce an inexpensive and easy-to-use surgery table containing a device for rodent mouth opening, which facilitates access to the oral cavity, maintaining mouth-opening and spreading the cheeks apart.
Warm and Dry Spells (WDS) in Austral Winter over Central South America
The horizontal and vertical structure of unusually warm and dry spells (WDS) over the central parts of South America during the winter and post-winter months (JJAS) are studied. During WDS the mean temperature and humidity anomalies over central Brazil are about +4.1°C and −13.2%, respectively. The mean duration of WDS is 11 days and their mean frequency is less than one per year during the months of JJAS. Apparently, WDS have no preference for the phase of ENSO. Widespread and persistent subsidence in the middle troposphere is observed in tropical Brazil during WDS, which renders the lower tropospheric air warm and dry. The negative anomalies of the specific humidity are observed to be associated with the subsidence regions. A strong, slow moving ridge in the eastern South Pacific and a low-pressure center in northern Argentina are important surface characteristics during the WDS. A more detailed investigation of two specific WDS events, a strong event (August–September 1999) and a moderate one (June 2002), shows a blocking-like situation in the 500-hPa geopotential and surface pressure fields in the Pacific. The South Atlantic subtropical high somewhat approaches the continent. Strong northerlies over the central and eastern parts of Brazil are also observed in the lower troposphere. During WDS the regional circulation acquires summertime characteristics, except for the absence of precipitation, and the circulation in the meridional plane is in the opposite sense from the Hadley circulation. A frontal system, supported by a 500-hPa trough, advances into central Brazil, causing the dissipation of the anomalous situation
Seleção de genes endógenos para análise de qRT-PCR em sementes de café.
A técnica quantitativa de PCR em tempo real, qRT-PCR, permite analisar a expressão de genes alvo em diferentes condições experimentais. No entanto, a análise precisa dos resultados gerados pela qRT-PCR está diretamente relacionada ao gene normalizador utilizado, o qual deve apresentar expressão constitutiva semelhante para as diferentes amostras/tratamentos avaliados no experimento. Os genes normalizadores escolhidos para as análises em sementes podem diferir daqueles utilizados para as raízes e folhas. Este trabalho teve como objetivo a avaliação de genes normalizadores úteis ao estudo de expressão gênica em sementes. O experimento englobou sementes mantidas nos frutos, sementes desmuciladas mecanicamente ou por meio da fermentação. Essas sementes e frutos foram em seguida, secados à sombra ou em secador até atingirem os teores de água de 12% ou 35%, foram acondicionados em embalagens herméticas e mantidos em câmara fria (10ºC/ 40%UR) por um período de até 12 meses. Foram avaliados 11 genes candidatos a normalizadores, os quais foram escolhidos, previamente, em um estudo de microarranjos. As expressões e estabilidade destes genes foram avaliadas por meio dos softwares geNorm, NormFinder, Delta Ct e BestKeeper. Pela análise conjunta dos resultados obtidos a partir destes softwares, observou-se que a estabilidade de um gene normalizador é variável em função do fator experimental considerado. O gene da actina é indicado como normalizador nas análises de expressão gênica em sementes de café quando forem considerados todos os três fatores avaliados neste estudo, ou seja, processamento, secagem e armazenamento
Changes in the structure due to strong winds in forest areas in the Pantanal, Brazil.
The Pantanal climate presents marked seasonality and eventually strong winds occur, especially in the beginning of the rainy season, which may last from September or October until April. A phytosociological study was conducted to evaluate the effects of a strong wind on the composition and structure of two forest formations in Pantanal wetland, a semideciduous forest (19º 15’ 32’’S and 55º 45’ 23.7’’W) and a forested savanna - “cerradão” (19° 17’ 21’’S and 55º 45’ 8.9’’W), with trees with diameter at breast height (DBH) ? 5 cm. After the strong wind, a reduction of 6% of the basal area and volume in the semideciduous forest was observed, mainly due to the uprooting of Xylopia aromatica trees. In the forested savanna, the basal area and volume reduction was even higher; an estimated 10%, representing 69 uprooted trees per hectare, mainly of Copaifera martii trees. In both areas it was observed that the uprooted trees presented an average height and diameter bigger than the trees that remained intact. Usually, the trees that were uprooted presented higher wood density and the species that had broken branches had a lower density
Influence of temperature and storage time on anthocyanin stability of grape juice treated by hot filling.
The objective of this study was to analyze the storage temperatures on anthocyanins content of grape juices bottled hot, simulating inadequate cooling and storage conditions
Correlações fenotípicas entre caracteres morfológicos e de produção de palmito em pupunheira.
Delayed luminescence in relation to the germination and vigour of coffee seeds: initial series with C. Arabica samples.
Ultra-weak delayed luminescence measurements on coffee seeds were run for samples submitted to different post-harvest treatments or in seed lots with different vigour levels obtained by accelerated aging, and both were induced to germinate afterwards. Parameters of hyperbolic decay fitting were correlated to the correspondent germination vigour, with a linear relation found for the initial value as well as for the decay velocity. These preliminary data point to further, broader validation for this non-invasive, non-destructive test for seed?s viability analyses
Desempenho inicial de sementes de milho tratadas com biorreguladores submetidas a déficit hídrico.
Edição Especial contendo os Anais do XVIII Congresso Brasileiro de Sementes, Florianópolis, set. 2013
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