Comets
Mostrando 1-12 de 33 artigos, teses e dissertações.
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1. LABORATORY INVESTIGATION OF X-RAY PHOTOLYSIS OF METHANOL ICE AND ITS IMPLICATION ON ASTROPHYSICAL ENVIRONMENTS
Methanol (CH3OH) is one of the most abundant organic molecules in astrophysical environments. It has been found in cold regions such as surfaces of comets, ices near young stellar objects and protoplanetary disks, as well as in the gas phase in different regions in space. In this work, we experimentally simulate the methanol ice and its behavior when irradia
Quím. Nova. Publicado em: 2020-05
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2. Polímeros orientados em ambientes aleatórios
Nesta dissertação, temos por objetivo estudar polímeros orientados em ambientes aleatáorios. Com base no artigo "Probabilistic Analysis of Directed Polymers in a Random Environment: a Review" escrito por F. Comets, T. Shiga e N. Yoshida em 2004, provaremos o comportamento difusivo de polímeros na fase de desordem fraca e o comportamento localizado na fa
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 20/09/2011
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3. Um modelo híbrido para a poeira cometária
In this Work, we present a systematic and uniform study involving the productivity of Comet 67P/Churyumov-Gerasimenko, target of ROSETTA Mission, during the 1982, 1996, and 2002 apparitions. Gas mass production rates [in g s-1] are obtained using hydroxyl radical (OH) rates [in molecules s-1], given in literature, considering that ~ 85% of the water photodis
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/02/2011
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4. Evaluation of extracts from Coccoloba mollis using the Salmonella/microsome system and in vivo tests
The common everyday use of medicinal plants is an ancient, and still very widespread practice, whereby the need for studies on their possible toxicity and mutagenic properties. The species Coccoloba mollis has been much used in phytotherapy, mainly in cases involving loss of memory and stress. In order to investigate its genotoxic and mutagenic potential, et
Genetics and Molecular Biology. Publicado em: 02/07/2010
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5. Passeios aleatórios e grandes desvios em ambientes aleatórios
O objetivo desta dissertação é estudar as propriedades do passeio aleatório em ambiente aleatório. Com base no artigo "Random Walk in Random Environment" escrito por O. Zeitouni, apresentaremos o Critério de Recorrência e Transiência do passeio aleatório e a Lei dos Grandes Números para o mesmo, obtidos inicialmente por F. Solomon. Em seguida, o es
Publicado em: 2010
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6. Application of the comet assay in erythrocytes of Oreochromis niloticus (Pisces): a methodological comparison
The present study applied the comet assay to erythrocytes of Oreochromis niloticus with the aim of improving protocols to detect DNA damage in these cells, by using two distinct pHs (pH = 12.1 and pH > 13) and evaluating whether there is a correspondence between silver and ethidium bromide staining. Comets were visually examined and, the frequency of cells w
Genetics and Molecular Biology. Publicado em: 23/01/2009
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7. MECHANISM STUDY OF THE PN AND NS FORMATION IN THE INTERSTELLAR, COMETARY AND PLANETARY MEDIUM / ESTUDO DOS MECANISMOS DE FORMAÇÃO DAS ESPÉCIES PN E NS NO MEIO INTERESTELAR, EM COMETAS E ATMOSFERAS PLANETÁRIAS
This study investigates the chemical mechanisms of PN and NS formations in the interstellar medium, comets and the atmosphere of giant planets such as Saturn and Jupiter. The quantum chemical calculations were performed by using the CCSD and CCSD(T) levels of theory. The basis sets used in this study were 6- 311++G(d,p) and 6-311++G(3df,3pd). Geometry optimi
Publicado em: 2009
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8. APLICATION OF THE MICROBIOLOGICAL METHOD DEFT/APC AND DNA COMET ASSAY TO DETECT IONIZING RADIATION PROCESSING OF MINIMALLY PROCESSED VEGETABLES / Aplicação do método microbiológico DEFT/APC e do Teste do Cometa na detecção do tratamento com radiação ionizante de hortaliças minimamente processadas
Marketing of minimally processed vegetables (MPV) are gaining impetus due to its convenience, freshness and apparent healthy. However, minimal processing does not reduce pathogenic microorganisms to safe levels. Food irradiation is used to extend the shelf life and inactivation of food-borne pathogens. Its combination with minimal processing could improve th
Publicado em: 2008
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9. Comet Assay applied to DNA damage study in fat snook, Centropomus parallelus (Poey, 1860), exposed to β-naphthoflavone / Aplicação do ensaio cometa a estudo de danos ao DNA de robalos, Centropomus parallelus (Poey, 1860), expostos à ß-naftoflavona
Single Cell Gel Electrophoresis or Comet Assay was applied to study the genotoxic potential of exposure in vivo to β-naphthoflavone (BNF) on erythrocytes of fat snook, Centropomus parallelus. Specific conditions for the comet assay on fat snook blood cells were established based on information obtained from literature together with results of experiment
Publicado em: 2006
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10. The capture of comets by swing-by
In this paper, numerical simulations are made, using the restricted three-body problem as the mathematical model, to calculate the effects of a swing-by with the planet Jupiter in the orbit of a comet. In particular, the orbital elements of the comets are calculated after the passage by Jupiter, the distribution obtained is shown and the probability of captu
Computational & Applied Mathematics. Publicado em: 2005-04
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11. Estudo do efeito dos metabólitos do benzeno e tolueno sobre as mitocôndris cerebrais e hepáticas de ratos
Aim: The aim of this work was to investigate the hypothesis that catechol and 3MC inhibit FADH2-linked basal respiration in mitochondria isolated from rat liver and brain homogenates. Moreover, catechol ability to induce DNA damage in rat brain cells through the comet assay (alkaline single-cell gel electrophoresis assay) was also observed. Methods: Two diff
Publicado em: 2005
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12. Evaluation of radioinduced damage and repair capacity in blood lymphocytes of breast cancer patients
Genetic damage caused by ionizing radiation and repair capacity of blood lymphocytes from 3 breast cancer patients and 3 healthy donors were investigated using the comet assay. The comets were analyzed by two parameters: comet tail length and visual classification. Blood samples from the donors were irradiated in vitro with a 60Co source at a dose rate of 0.
Brazilian Journal of Medical and Biological Research. Publicado em: 2001-02