217 research outputs found
Caracterização espectral de solos utilizando espectrorradiômetro em laboratório e imagem de satélite hiperespectral.
Data obtained with hyperspectral remote sensors have the advantage of containing a great spectral resolution, offering more details about spectral behavior of a particular target. The use of these images show high potential to describe soil mineralogical attributes. The main objective of this study was to obtain the spectral and mineralogical attributes of soils using hyperspectral satellite imagery and with data acquired at ground level; evaluation of a supervised classification routine for determination of soils texture; and estimate clay using multivariate analysis. Soil samples were collected at a 0-20cm depth and spectral measurements, texture and mineralogy analysis were made. Using GIS software, image processing and statistical packages, the information obtained in the laboratory has been analyzed. The use of hyperspectral imagery enhanced the mineralogical characterization of the studied area. The maximum likelihood classification algorithm showed great skill in distinguishing between four textures class created with the aim of hyperspectral data. The statistical method PLSR provided a satisfactory prediction of clay and sand, using data collected in the laboratory, with high coefficients of determination and low error values (RMSE)
Perfil de ácidos graxos no Longissimus dorsi de cordeiros Santa Inês alimentados com diferentes níveis energéticos.
Resumo: O presente estudo objetivou avaliar a influência de rações com diferentes níveis de energia metabolizável sobre o teor de lipídeos totais, colesterol e perfil de ácidos graxos no músculo Longissimus dorsi de cordeiros Santa Inês. Foram utilizados 20 cordeiros, com idade e peso de 50 dias e 13,0 ± 0,56 kg, respectivamente, alimentados com rações contendo diferentes níveis energéticos: 2,08; 2,28; 2,47 e 2,69 Mcal/kgMS. Os animais foram pesados semanalmente para acompanhamento do ganho de peso vivo, quando a média do peso vivo do tratamento atingiu 28 kg, os animais foram abatidos. A análise do perfil lipídico do músculo Longissimus dorsi apresentou efeito linear crescente e decrescente para os ácidos Cis-10 heptadecanóico (C17:1) e eicosatrienóico (C20:3), respectivamente, com o aumento nos níveis de energia dietéticos (P0,05). A manipulação dietética influencia o perfil lipídico no Longissimus dorsi de cordeiros Santa Inês. [Fatty acids profile in Longissimus dorsi of Santa Ines lambs fed with different energy levels]. Abstract: This study evaluated the influence of rations with different levels of metabolizable energy on the content of total lipids, cholesterol and fatty acid profile of the longissimus dorsi of Santa Ines lambs. Twenty Santa Ines lambs were used, with age and body weight of 50 days and 13.0 ± 0.56 kg, respectively, fed rations with different energy levels: 2.08; 2.28; 2.47 e 2.69 Mcal/kgDM. Animals were weighed weekly to follow their body weight gain (BWG); when the mean BW of the treatment reached 28 kg, the animals were slaughtered. The analysis of the lipid profile of Longissimus dorsi presented linear increasing and decreasing for the Cis-10 heptadecanoic acid (C17:1) and eicosatrienoic (C20:3), respectively, with the increasing dietary energy levels (P 0.05). The dietary manipulation influences the lipid profile in Longissimus dorsi of Santa Ines lambs
Sugarcane (Saccharum X officinarum): a reference study for the regulation of genetically modified cultivars in Brazil.
Electrophoresis and spectrometric analyses of adaptation-related proteins in thermally stressed Chromobacterium violaceum.
Chromobacterium violaceum is a Gram-negative proteobacteria found in water and soil; it is widely distributed in tropical and subtropical regions, such as the Amazon rainforest. We examined protein expression changes that occur in C. violaceum at different growth temperatures using electrophoresis and mass spectrometry
Efeito aditivo de substâncias isoladas de Brachiaria brizantha em ensaios alelopáticos frente a plantas invasoras de pastagens.
BF Integrase Genes of HIV-1 Circulating in São Paulo, Brazil, with a Recurrent Recombination Region
Although some studies have shown diversity in HIV integrase (IN) genes, none has focused particularly on the gene evolving in epidemics in the context of recombination. The IN gene in 157 HIV-1 integrase inhibitor-naïve patients from the São Paulo State, Brazil, were sequenced tallying 128 of subtype B (23 of which were found in non-B genomes), 17 of subtype F (8 of which were found in recombinant genomes), 11 integrases were BF recombinants, and 1 from subtype C. Crucially, we found that 4 BF recombinant viruses shared a recurrent recombination breakpoint region between positions 4900 and 4924 (relative to the HXB2) that includes 2 gRNA loops, where the RT may stutter. Since these recombinants had independent phylogenetic origin, we argue that these results suggest a possible recombination hotspot not observed so far in BF CRF in particular, or in any other HIV-1 CRF in general. Additionally, 40% of the drug-naïve and 45% of the drug-treated patients had at least 1 raltegravir (RAL) or elvitegravir (EVG) resistance-associated amino acid change, but no major resistance mutations were found, in line with other studies. Importantly, V151I was the most common minor resistance mutation among B, F, and BF IN genes. Most codon sites of the IN genes had higher rates of synonymous substitutions (dS) indicative of a strong negative selection. Nevertheless, several codon sites mainly in the subtype B were found under positive selection. Consequently, we observed a higher genetic diversity in the B portions of the mosaics, possibly due to the more recent introduction of subtype F on top of an ongoing subtype B epidemics and a fast spread of subtype F alleles among the B population
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