1,555 research outputs found

    Avaliação biométrica do terço posterior de bovinos de raça alentejana: resultados preliminares

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    The biometric evaluation is an evaluation method that aims to know the size of the animals from the measurement of several biometric elements. This type of evaluation should be associated with linear evaluation to understand which animals have desirable characteristics related to growth and muscular development. The aim of this study was to perform a biometric evaluation of the backpart of Alentejana cattle portuguese breed; the specific objectives were to perform measurements of various elements of the animal, like thoracic perimeter, body length, width and length of the rump. This work has been carried out so far in several farms affiliated with the breeders association (Associação dos Criadores de Bovinos da Raça Alentejana), based in Herdade da Coutada Real in Assumar, Monforte, between April and June 2017. 134 animals were measured during this period but a wider database was used, with information from 1342 animals from the breeder´s association, with measurements and presenting global reference values: the height at the withers (1,34±0,60m in females and 1,50±0,02m in males), the body length (1,617±0,900m in females and 1,77±0,02m in males), the thoracic perimeter (2,057±0,900m in females and 2,373±0,046m in males), the rump length (0,558±0,430m in females and 0,626±0,009m in males), the outside rump width (0,557±0,004m in females and 0,734±0,059m in males) and the hip-femural width (0,492±0,060m in females and 0,548±0,014m in males). From the results obtained we concluded that there was a positive evolution over the years, related to the animal’s size and conformation and we noticed a great homogeneity between animals, which is justified by values of standard deviation (between 0.030 and 0.207) and coefficient of variation low (between 5.8% and 14%). This type of evaluation is still rarely used by breeder’s associations, but there is expected that their use will help them in the selection and breeding of animals, when associated with other selection methods, like linear evaluation.info:eu-repo/semantics/publishedVersio

    Genome-wide identification of Saccharomyces cerevisiae genes required for tolerance to acetic acid

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    <p>Abstract</p> <p>Background</p> <p>Acetic acid is a byproduct of <it>Saccharomyces cerevisiae </it>alcoholic fermentation. Together with high concentrations of ethanol and other toxic metabolites, acetic acid may contribute to fermentation arrest and reduced ethanol productivity. This weak acid is also a present in lignocellulosic hydrolysates, a highly interesting non-feedstock substrate in industrial biotechnology. Therefore, the better understanding of the molecular mechanisms underlying <it>S. cerevisiae </it>tolerance to acetic acid is essential for the rational selection of optimal fermentation conditions and the engineering of more robust industrial strains to be used in processes in which yeast is explored as cell factory.</p> <p>Results</p> <p>The yeast genes conferring protection against acetic acid were identified in this study at a genome-wide scale, based on the screening of the EUROSCARF haploid mutant collection for susceptibility phenotypes to this weak acid (concentrations in the range 70-110 mM, at pH 4.5). Approximately 650 determinants of tolerance to acetic acid were identified. Clustering of these acetic acid-resistance genes based on their biological function indicated an enrichment of genes involved in transcription, internal pH homeostasis, carbohydrate metabolism, cell wall assembly, biogenesis of mitochondria, ribosome and vacuole, and in the sensing, signalling and uptake of various nutrients in particular iron, potassium, glucose and amino acids. A correlation between increased resistance to acetic acid and the level of potassium in the growth medium was found. The activation of the Snf1p signalling pathway, involved in yeast response to glucose starvation, is demonstrated to occur in response to acetic acid stress but no evidence was obtained supporting the acetic acid-induced inhibition of glucose uptake.</p> <p>Conclusions</p> <p>Approximately 490 of the 650 determinants of tolerance to acetic acid identified in this work are implicated, for the first time, in tolerance to this weak acid. These are novel candidate genes for genetic engineering to obtain more robust yeast strains against acetic acid toxicity. Among these genes there are number of transcription factors that are documented regulators of a large percentage of the genes found to exert protection against acetic acid thus being considered interesting targets for subsequent genetic engineering. The increase of potassium concentration in the growth medium was found to improve the expression of maximal tolerance to acetic acid, consistent with the idea that the adequate manipulation of nutrient concentration of industrial growth medium can be an interesting strategy to surpass the deleterious effects of this weak acid in yeast cells.</p

    QuĂ­mica da vida : centros activos em metaloproteĂ­nas

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    Académico - LicenciaturasImportância da catálise em sistemas biológicos. Função das metaloproteínas. Apresentação de exemplos ilustrativos: centros hémicos, ferro-enxofre, cobre, zinco e molibdênio

    QuĂ­mica da vida : meio ambiente e ciclos dos elementos

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    Académico - LicenciaturasEste vídeo demonstra como os elementos químicos são utilizados e reciclados. O ciclo do azoto é, em geral, usado como exemplo. A importância dos fertilizantes azotados é apresentada e a sua relação com a produtividade agrícola discutida. Compara-se a produção de fertilizantes azotados por via industrial e biológica. Discute-se ainda a transformação de nitratos e nitritos e as implicações ambientais. Aborda-se o papel dos sistemas biológicos na despoluição e tratamento de efluentes

    QuĂ­mica da vida : ciclos dos elementos : enxofre

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    Académico - LicenciaturasOs elementos químicos são transformados de um modo cíclico, onde o papel da biologia é particularmente ativo. O enxofre é usado como modelo. Este ciclo é utilizado para introduzir conceitos tais como: assimilação, dissimilação e respiração no sentido lato

    Synechocystis ferredoxin/ferredoxin-NADP+-reductase/NADP+ complex: Structural model obtained by NMR-restrained docking

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    FEBS Letters 579 (2005) 4585–4590Abstract Ferredoxin (Fd) and ferredoxin-NADP+-reductase(FNR) are two terminal physiological partners of the photosynthetic electron transport chain. Based on a nuclear magnetic resonance(NMR)-restrained-docking approach, two alternative structural models of the Fd–FNR complex in the presence of NADP+ are proposed. The protein docking simulations were performed with the software BiGGER. NMR titration revealed a 1:1 stoichiometry for the complex and allowed the mapping of the interacting residues at the surface of Fd. The NMR chemical shifts were encoded into distance constraints and used with theoretically calculated electronic coupling between the redox cofactors to propose experimentally validated docked complexes

    Química da vida : moléculas da vida

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    Académico - LicenciaturasDescrição das moléculas relevantes para os sistemas vivos: aminoácidos (proteínas), ácidos nucleicos, açúcares e lípidos

    Origin and Epidemiological History of HIV-1 CRF14_BG

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    This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Users must also make clear the license terms under which the work was published. CC BY Licence: http://creativecommons.org/licenses/by/4.0/Background: CRF14_BG isolates, originally found in Spain, are characterized by CXCR4 tropism and rapid disease progression. This study aimed to identify the origin of CRF14_BG and reconstruct its epidemiological history based on new isolates from Portugal.Methodology/Principal Findings: C2V3C3 env gene sequences were obtained from 62 samples collected in 1993–1998 from Portuguese HIV-1 patients. Full-length genomic sequences were obtained from three patients. Viral subtypes, diversity, divergence rate and positive selection were investigated by phylogenetic analysis. The molecular structure of the genomes was determined by bootscanning. A relaxed molecular clock model was used to date the origin of CRF14_BG. Geno2pheno was used to predict viral tropism. Subtype B was the most prevalent subtype (45 sequences; 73%) followed by CRF14_BG (8; 13%), G (4; 6%), F1 (2; 3%), C (2; 3%) and CRF02_AG (1; 2%). Three CRF14_BG sequences were derived from 1993 samples. Near full-length genomic sequences were strongly related to the CRF14_BG isolates from Spain. Genetic diversity of the Portuguese isolates was significantly higher than the Spanish isolates (0.044 vs 0.014, P,0.0001). The mean date of origin of the CRF14_BG cluster was estimated to be 1992 (range, 1989 and 1996) based on the subtype G genomic region and 1989 (range, 1984–1993) based on the subtype B genomic region. Most CRF14_BG strains (78.9%) were predicted to be CXCR4. Finally, up to five amino acids were under selective pressure in subtype B V3 loop whereas only one was found in the CRF14_BG cluster.Conclusions: CRF14_BG emerged in Portugal in the early 1990 s soon after the beginning of the HIV-1 epidemics, spread to Spain in late 1990 s as a consequence of IVDUs migration and then to the rest of Europe. CXCR4 tropism is a general characteristic of this CRF that may have been selected for by escape from neutralizing antibody response

    Global collision-risk hotspots of marine traffic and the world’s largest fish, the whale shark

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    © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Womersley, F. C., Humphries, N. E., Queiroz, N., Vedor, M., da Costa, I., Furtado, M., Tyminski, J. P., Abrantes, K., Araujo, G., Bach, S. S., Barnett, A., Berumen, M. L., Bessudo Lion, S., Braun, C. D., Clingham, E., Cochran, J. E. M., de la Parra, R., Diamant, S., Dove, A. D. M., Dudgeon, C. L., Erdmann, M. V., Espinoza, E., Fitzpatrick, R., González Cano, J., Green, J. R., Guzman, H. M., Hardenstine, R., Hasan, A., Hazin, F. H. V., Hearn, A. R., Hueter, R. E., Jaidah, M. Y., Labaja, J., Ladinol, F., Macena, B. C. L., Morris Jr., J. J., Norman, B. M., Peñaherrera-Palmav, C., Pierce, S. J., Quintero, L. M., Ramırez-Macías, D., Reynolds, S. D., Richardson, A. J., Robinson, D. P., Rohner, C. A., Rowat, D. R. L., Sheaves, M., Shivji, M. S., Sianipar, A. B., Skomal, G. B., Soler, G., Syakurachman, I., Thorrold, S. R., Webb, D. H., Wetherbee, B. M., White, T. D., Clavelle, T., Kroodsma, D. A., Thums, M., Ferreira, L. C., Meekan, M. G., Arrowsmith, L. M., Lester, E. K., Meyers, M. M., Peel, L. R., Sequeira, A. M. M., Eguıluz, V. M., Duarte, C. M., & Sims, D. W. Global collision-risk hotspots of marine traffic and the world’s largest fish, the whale shark. Proceedings of the National Academy of Sciences of the United States of America, 119(20), (2022): e2117440119, https://doi.org/10.1073/pnas.2117440119.Marine traffic is increasing globally yet collisions with endangered megafauna such as whales, sea turtles, and planktivorous sharks go largely undetected or unreported. Collisions leading to mortality can have population-level consequences for endangered species. Hence, identifying simultaneous space use of megafauna and shipping throughout ranges may reveal as-yet-unknown spatial targets requiring conservation. However, global studies tracking megafauna and shipping occurrences are lacking. Here we combine satellite-tracked movements of the whale shark, Rhincodon typus, and vessel activity to show that 92% of sharks’ horizontal space use and nearly 50% of vertical space use overlap with persistent large vessel (>300 gross tons) traffic. Collision-risk estimates correlated with reported whale shark mortality from ship strikes, indicating higher mortality in areas with greatest overlap. Hotspots of potential collision risk were evident in all major oceans, predominantly from overlap with cargo and tanker vessels, and were concentrated in gulf regions, where dense traffic co-occurred with seasonal shark movements. Nearly a third of whale shark hotspots overlapped with the highest collision-risk areas, with the last known locations of tracked sharks coinciding with busier shipping routes more often than expected. Depth-recording tags provided evidence for sinking, likely dead, whale sharks, suggesting substantial “cryptic” lethal ship strikes are possible, which could explain why whale shark population declines continue despite international protection and low fishing-induced mortality. Mitigation measures to reduce ship-strike risk should be considered to conserve this species and other ocean giants that are likely experiencing similar impacts from growing global vessel traffic.Funding for data analysis was provided by the UK Natural Environment Research Council (NERC) through a University of Southampton INSPIRE DTP PhD Studentship to F.C.W. Additional funding for data analysis was provided by NERC Discovery Science (NE/R00997/X/1) and the European Research Council (ERC-AdG-2019 883583 OCEAN DEOXYFISH) to D.W.S., Fundação para a Ciência e a Tecnologia (FCT) under PTDC/BIA/28855/2017 and COMPETE POCI-01–0145-FEDER-028855, and MARINFO–NORTE-01–0145-FEDER-000031 (funded by Norte Portugal Regional Operational Program [NORTE2020] under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund–ERDF) to N.Q. FCT also supported N.Q. (CEECIND/02857/2018) and M.V. (PTDC/BIA-COM/28855/2017). D.W.S. was supported by a Marine Biological Association Senior Research Fellowship. All tagging procedures were approved by institutional ethical review bodies and complied with all relevant ethical regulations in the jurisdictions in which they were performed. Details for individual research teams are given in SI Appendix, section 8. Full acknowledgments for tagging and field research are given in SI Appendix, section 7. This research is part of the Global Shark Movement Project (https://www.globalsharkmovement.org)
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