731 research outputs found
A nonequilibrium renormalization group approach to turbulent reheating
We use nonequilibrium renormalization group (RG) techniques to analyze the
thermalization process in quantum field theory, and by extension reheating
after inflation. Even if at a high scale the theory is described by a
non-dissipative theory, the RG running induces nontrivial
noise and dissipation. For long wavelength, slowly varying field
configurations, the noise and dissipation are white and ohmic, respectively.
The theory will then tend to thermalize to an effective temperature given by
the fluctuation-dissipation theorem.Comment: 8 pages, 2 figures; to appear in J. Phys. A; more detailed account of
the calculation of the noise and dissipation kernel
Inflation and nonequilibrium renormalization group
We study de spectrum of primordial fluctuations and the scale dependence of
the inflaton spectral index due to self-interactions of the field. We compute
the spectrum of fluctuations by applying nonequilibrium renormalization group
techniques.Comment: 6 pages, 1 figure, submitted to J. Phys.
Genetic characterization of Indubrasil cattle breed population.
Abstract The Indubrasil breed was developed in the Brazilian region called Triângulo Mineiro as a result of a cross between zebu cattle. Initially, it was used as a terminal cross and currently it represents approximately 4.45% of all the Brazilian zebu cattle. Studies were conducted to estimate genetic parameters in the Indubrasil using pedigree information, however, until now, no study has been developed using large-scale genomic markers in this breed. Pedigree information are widely used to investigate population parameters; however, they can neglect some estimates when compared to the use of genomic markers. Therefore, the objective of this study was to investigate the population structure and the genetic diversity of Indubrasil cattle using a high-density Single Nucleotide Polymorphism (SNP) panel (Illumina BovineHD BeadChip 700k). Levels of genomic homozygosity were evaluated using three different approaches: Runs of homozygosity (FROH), % of homozygosis (FSNP), and inbreeding coefficient (Fx). Further, Runs of Homozygosity (ROH) segments conserved among the animals were investigated to identify possible regions associated with the breed characteristics. Our results indicate that even the Indubrasil breed having a small effective population size, the levels of homozygosity (FROH = 0.046) are still small. This was possibly caused by the cross conducted among different breeds for its development. It suggests no immediate risks associated with loss of genetic variation. This information might be used in breeding programs, for the breed conservation and for the expansion of the Indubrasil breed
Quando suínos asselvajados atingem a puberdade no Sul do Brasil?
Resumo: O objetivo deste estudo foi avaliar parâmetros reprodutivos e desenvolvimento corporal em Javalis (Sus scrofa) capturados na natureza para estabelecer categorias de fases de vida (idade) a partir da associação destes parâmetros. Vinte suínos asselvajados foram utilizados neste estudo. Os animais foram capturados na região Sul do Brasil como parte de um programa de controle populacional. Os animais foram pesados após o abate, testículos e epidídimos foram encaminhados sob refrigeração ao laboratório, onde tiveram o comprimento, largura e espessura medidos e os espermatozoides do epidídimo coletados. Foi observado que animais com menos de 30 kg de peso vivo e testículos com menos de 3,8 cm (comprimento) e 2,7 cm (largura) não apresentaram espermatozoides viáveis. Foi identificada uma correlação positiva entre os parâmetros testiculares com o peso do animal. Após a coleta de sêmen do epidídimo, foi verificada boa qualidade espermática nos machos acima de 30 kg, sendo que apenas um macho apresentou azoospermia. Em conclusão, o peso corporal e a biometria testicular foram positivamente correlacionados em Javalis selvagens, indicando que estão capazes de se reproduzir, produzindo esperma viável, após atingir 30 kg de peso vivo, podendo ser usado como parâmetro para caracterizar a fase de vida reprodutiva
Posição das câmaras de coleta para monitoramento da emissão de gases de efeito estufa do solo em plantios florestais de Pinus.
Obtenção da farinha de bocaiuva (Acrocomia aculeata (Jacq.) Lodd. ex Mart) na Casa do Artesão de Corumbá-MS.
A farinha de bocaiuva é um produto tradicional de Corumbá, muito utilizada para elaboração de gêneros alimentícios como, por exemplo, biscoitos, bolos, pães, mingau, etc. O presente trabalho descreve o processo de obtenção da farinha de bocaiuva (Acrocomia aculeata (Jacq.) Lodd. ex Mart) realizado na Casa do Artesão de Corumbá-MS, a partir de entrevistas feitas com o artesão Sr Gilberto Rolon, principal produtor desta farinha em Corumbá e região. Foram coletados dados, informações e materiais, monitorando-se os equipamentos e utensílios que o artesão normalmente utiliza no processo. Juntamente com o Sr Gilberto a farinha de bocaiuva foi obtida, cujo rendimento foi avaliado durante o processo artesanal/mecânico a partir da matéria prima (polpa desidratada obtida artesanalmente) trazida de Comunidades da região. Primeiramente, a polpa desidratada foi selecionada conforme sua variação de cores (amarelo claro, amarelo escura, laranja avermelhada), em seguida o material foi exposto ao sol para a desidratação final. Misturouse as polpas pouco antes da trituração mecânica para obtenção da farinha. Observa-se que o rendimento da obtenção da farinha é de 72,8% um rendimento considerável a partir da matéria prima utilizada que ultrapassou o rendimento esperado pelo Sr Gilberto, ressaltamos que a farinha depende também da seleção da polpa e variação de cores. The flour of bocaiuva is a product traditional Corumbá, very used for elaboration of genres foods, such as for example biscuits, cakes, bread, porridge, etc.The present work describes the process of obtaining flour bocaiuva (Acrocomia aculeata (Jacq.) Lodd. Mart ex) held at the home of artisan Corumbá-MS, from interviews made with the craftsman Mr Gilberto Rolon, the main producer this flour on Corumbá and region. We collected data, information and materials, by monitoring the equipment and utensils that the craftsman normally uses in the process. Along with Mr. Gilberto the flour bocaiuva was obtained, whose the yield was valued during the process artisanal/ mechanic as from of raw materials (dehydrated pulp obtained artisanally) in brought the Communities the region. We first, the pulp dehydrated, was selected by the its of colors variation (light yellow, dark yellow, reddish orange), Then material was exposed to sunlight, for the dehydration the end. Mixed if the pulps shortly before trituration mechanics to obtain flour. It is observed that the yield of obtaining flour is 72.8% yield considerably from the raw material used which exceeded the expected yield by Mr. Gilberto, we emphasize that the flour also depends on the selection of pulps and color variation.Também em: SEMINÁRIO DE AGROECOLOGIA DE MATO GROSSO DO SUL, 4.; ENCONTRO DE PRODUTORES AGROECOLÓGICOS DE MS, 3., 2012, Glória de Dourados. O saber tradicional e o científico: a interação encurtando caminhos para o desenvolvimento sustentável: anais. Brasília, DF: Embrapa, 2012. 1 CD-ROM. Editado por: Leandro Fávio Carneiro, Milton Parron Padovan
Housing Conditions and a Challenge with Lipopolysaccharide on the Day of Estrus Can Influence Gene Expression of the Corpus Luteum in Gilts.
Abstract: The corpus luteum (CL) is a temporary endocrine gland that plays a decisive role in the reproductive physiology of gilts. Recently, it has been suggested that exogenous factors may compromise the normal functioning of the CL. In the present study, we aimed to understand to what extent an acute and systemic challenge with lipopolysaccharide (LPS) on the day of estrus could compromise gene expression of gilts' CLs housed in different welfare conditions. For this, we housed 42 gilts in three different housing systems: crates, indoor group pens, and outdoor housing. Then, we challenged six females from each group with LPS and eight with saline (SAL) on the day of estrus. After slaughtering the gilts on the fifth day after the challenge, ovaries were collected for gene expression analysis by RT-qPCR. Housing system and LPS challenge did not have a significant interaction for any genes evaluated; thus, their effects were studied separately. We identified significant (p < 0.05) downregulation of the angiogenic genes VEGF and FTL1 among LPS-challenged animals. Meanwhile, we also observed upregulation of HSD3B1 gene among LPS-challenged animals. We found that STAR and LHCGR genes were differentially expressed depending on the housing system, which indicates that the environment may affect adaptation capabilities. Our results indicate that an acute health challenge on the estrus day alters CL gene expression; however, the role of the housing system remains uncertain
Gold catalysts supported on ceria doped by rare earth metals for water gas shift reaction: Influence of the preparation method
Cataloged from PDF version of article.Gold catalysts based on ceria, doped by various RE metals (La, Sm, Gd, Yb, Y) were studied. The influence of the preparation methods on structure, properties and catalytic activity in the WGS reaction was investigated. The catalysts' supports were prepared using two different methods: co-precipitation (CP) and mechanochemical activation (MA). The catalysts were tested in a wide temperature interval without and after reactivation. All samples were characterized using a combination of X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Raman spectroscopy (RS) and X-ray photoelectron spectroscopy (XPS) and TPR. It was found that the catalytic activity of MA catalysts is higher than CP ones. The gold catalysts based on ceria doped by Yb and Sm exhibited the highest activity. After reactivation in air the MA samples almost kept the WGS activity same, while the CP catalysts increased it. The catalysts of a single- and double-phase structure are formed as a result of CP and MA preparation, respectively. There are no big differences in the gold particles size (2-3 nm) depending on dopants and on the preparation techniques. The RS spectra analysis indicates that most probably the oxygen vacancies are adjacent to Me(3+) dopant and the ceria structure seems to be better ordered than in the case of alumina as a dopant. There is no distinct correlation between reducibility and WGS activity. The XPS analysis disclose positively charged gold particles in addition to metallic gold within a surface region of fresh samples and only metallic gold on the samples after catalytic processing. There is no simple correlation between the concentration of Ce(3+) in the samples and their WGS activity. (C) 2009 Elsevier B.V. All rights reserved
Avaliação da água de coco e albúmen sólido na determinação de agrotóxicos por QuEChERS UHPLCMS/MS.
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