999 resultados para Animal Structures


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The primary objective of this project was to determine the effect of bridge width on deck cracking in bridges. Other parameters, such as bridge skew, girder spacing and type, abutment type, pier type, and number of bridge spans, were also studied. To achieve the above objectives, one bridge was selected for live-load and long-term testing. The data obtained from both field tests were used to calibrate a three-dimensional (3D) finite element model (FEM). Three different types of loading—live loading, thermal loading, and shrinkage loading—were applied. The predicted crack pattern from the FEM was compared to the crack pattern from bridge inspection results. A parametric study was conducted using the calibrated FEM. The general conclusions/recommendations are as follows: -- Longitudinal and diagonal cracking in the deck near the abutment on an integral abutment bridge is due to the temperature differences between the abutment and the deck. Although not likely to induce cracking, shrinkage of the deck concrete may further exacerbate cracks developed from thermal effects. -- Based upon a limited review of bridges in the Iowa DOT inventory, it appears that, regardless of bridge width, longitudinal and diagonal cracks are prevalent in integral abutment bridges but not in bridges with stub abutments. -- The parametric study results show that bridge width and skew have minimal effect on the strain in the deck bridge resulting from restrained thermal expansion. -- Pier type, girder type, girder spacing, and number of spans also appear to have no influence on the level of restrained thermal expansion strain in the deck near the abutment.

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EHESS/CNRS, Programme de recherches interdisciplinaires sur le monde musulman périphérique

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Accumulating evidence supports a role for brain-derived neurotrophic factor (BDNF) in depression. However, most of these studies have been performed in animal models that have a low face validity with regard to the human disease. Here, we examined the regulation of BDNF expression in the hippocampus and amygdala of rats subjected to the chronic mild stress (CMS) model of depression, a paradigm that induces anhedonia, a core symptom of depression. We found that exposure of rats to the CMS paradigm did not modulate BDNF mRNA expression in the hippocampus and amygdala. In addition, chronic administration of imipramine, which reversed CMS-induced anhedonia, did not alter BDNF mRNA expression in these limbic structures.

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We have determined high-resolution crystal structures of the complexes of HLA-A2 molecules with two modified immunodominant peptides from the melanoma tumor-associated protein Melan-A/Melanoma Ag recognized by T cells-1. The two peptides, a decamer and nonamer with overlapping sequences (ELAGIGILTV and ALGIGILTV), are modified in the second residue to increase their affinity for HLA-A2. The modified decamer is more immunogenic than the natural peptide and a candidate for peptide-based melanoma immunotherapy. The crystal structures at 1.8 and 2.15 A resolution define the differences in binding modes of the modified peptides, including different clusters of water molecules that appear to stabilize the peptide-HLA interaction. The structures suggest both how the wild-type peptides would bind and how three categories of cytotoxic T lymphocytes with differing fine specificity might recognize the two peptides.

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The Americans with Disabilities Act (ADA) and the Fair Housing Act (FHA) prohibit discrimination on the basis of disability and govern the use of service or emotional support animals in places where pets may not be permitted. However, courts have been struggling with how to define and treat animals that qualify for protection under each law. This has created confusion as to what rights and duties are owed disabled persons and the animals that live with or accompany them. This essay attempts to clarify these two federal laws with regard to service or emotional support animals and the differing parties‘ rights and interests. It also includes an overview of select state laws that govern assistance animals of all types and our recommendations for enhancing the Iowa Civil Rights Act.

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O objetivo deste trabalho foi rastrear a inclussão de farinhas de origem animal em rações para frango de corte com ou sem levedura de cana-de-açúcar e farelo de trigo, por meio da análise do músculo peitoral das aves pelas técnicas dos isótopos estáveis de carbono e nitrogênio. Foram utilizados 210 pintos machos (Cobb), com um dia de idade, distribuídos aleatoriamente em sete tratamentos de 30 aves cada, tendo sido um tratamento controle (dieta vegetal) e seis com inclusão de farinha de carne e ossos bovina ou farinha de vísceras de aves na dieta, com ou sem levedura de cana-de-açúcar e farelo de trigo. Aos 42 dias de idade, foram abatidas quatro aves, por tratamento, escolhidas ao acaso, cujo músculo peitoral foi retirado para análise da razão isotópica. Os resultados obtidos foram submetidos à análise multivariada. Os tratamentos experimentais diferiram do tratamento controle, e foi identificada a inclusão de farinha de origem animal, pelas técnicas dos isótopos estáveis, mesmo com inclusão de levedura ou farelo de trigo na dieta.

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O objetivo deste trabalho foi avaliar a produção animal e sua relação com as características dos pastos de Brachiaria brizantha cultivares Marandu, Xaraés e Piatã. O delineamento experimental foi o de blocos ao acaso, com três tratamentos e duas repetições. Os piquetes com 2 ha foram subdivididos em dois e submetidos ao pastejo alternado, com 28 dias de utilização e 28 dias de descanso. Foram utilizados três novilhos teste, por piquete, e novilhos reguladores para manter resíduos pós pastejo em torno de 3 Mg ha-1 de matéria seca. Mensalmente, os pastos foram avaliados para se estimar o valor nutritivo da forragem. Os animais foram pesados, e as taxas de lotação foram ajustadas duas vezes por semana. No pasto da cv. Xaraés, apesar do menor ganho médio diário (GMD) dos animais, a taxa de lotação foi maior, o que resultou em maior produtividade da cv. Xaraés, em comparação às cvs. Marandu e Piatã. No pasto da cv. Piatã, houve aumento do GMD, o que indica que as cvs. Xaraés e Piatã são novas alternativas para a diversificação dos pastos no Cerrado. Assim, a escolha da forragem deve se dar em razão da meta do sistema de produção, ou seja, a produção por animal ou por área.

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BACKGROUND: Systematic reviews and meta-analyses of pre-clinical studies, in vivo animal experiments in particular, can influence clinical care. Publication bias is one of the major threats of validity in systematic reviews and meta-analyses. Previous empirical studies suggested that systematic reviews and meta-analyses have become more prevalent until 2010 and found evidence for compromised methodological rigor with a trend towards improvement. We aim to comprehensively summarize and update the evidence base on systematic reviews and meta-analyses of animal studies, their methodological quality and assessment of publication bias in particular. METHODS/DESIGN: The objectives of this systematic review are as follows: âeuro¢To investigate the epidemiology of published systematic reviews of animal studies until present. âeuro¢To examine methodological features of systematic reviews and meta-analyses of animal studies with special attention to the assessment of publication bias. âeuro¢To investigate the influence of systematic reviews of animal studies on clinical research by examining citations of the systematic reviews by clinical studies. Eligible studies for this systematic review constitute systematic reviews and meta-analyses that summarize in vivo animal experiments with the purpose of reviewing animal evidence to inform human health. We will exclude genome-wide association studies and animal experiments with the main purpose to learn more about fundamental biology, physical functioning or behavior. In addition to the inclusion of systematic reviews and meta-analyses identified by other empirical studies, we will systematically search Ovid Medline, Embase, ToxNet, and ScienceDirect from 2009 to January 2013 for further eligible studies without language restrictions. Two reviewers working independently will assess titles, abstracts, and full texts for eligibility and extract relevant data from included studies. Data reporting will involve a descriptive summary of meta-analyses and systematic reviews. DISCUSSION: Results are expected to be publicly available later in 2013 and may form the basis for recommendations to improve the quality of systematic reviews and meta-analyses of animal studies and their use with respect to clinical care.

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BACKGROUND: In animal farming, respiratory disease has been associated with indoor air contaminants and an excess in FEV1 decline. Our aim was to determine the characteristics and risk factors for chronic obstructive pulmonary disease (COPD) in never-smoking European farmers working inside animal confinement buildings. METHODS: A sample of participants in the European Farmers' Study was selected for a cross-sectional study assessing lung function and air contaminants. Dose-response relationships were assessed using logistic regression models. RESULTS: COPD was found in 18 of 105 farmers (45.1 SD 11.7 years) (17.1%); 8 cases (7.6%) with moderate and 3 cases (2.9%) with severe disease. Dust and endotoxin showed a dose-response relationship with COPD, with the highest prevalence of COPD in subjects with high dust (low=7.9%/high=31.6%) and endotoxin exposure (low=10.5%/high=20.0%). This association was statistically significant for dust in the multivariate analysis (OR 6.60, 95% CI 1.10-39.54). CONCLUSION: COPD in never-smoking animal farmers working inside confinement buildings is related to indoor dust exposure and may become severe. [Authors]

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The biodiversity of soil communities remains very poorly known and understood. Soil biological sciences are strongly affected by the taxonomic crisis, and most groups of animals in that biota suffer from a strong taxonomic impediment. The objective of this work was to investigate how DNA barcoding - a novel method using a microgenomic tag for species identification and discrimination - permits better evaluation of the taxonomy of soil biota. A total of 1,152 barcode sequences were analyzed for two major groups of animals, collembolans and earthworms, which presented broad taxonomic and geographic sampling. Besides strongly reflecting the taxonomic impediment for both groups, with a large number of species-level divergent lineages remaining unnamed so far, the results also highlight a high level (15%) of cryptic diversity within known species of both earthworms and collembolans. These results are supportive of recent local studies using a similar approach. Within an impeded taxonomic system for soil animals, DNA-assisted identification tools can facilitate and improve biodiversity exploration and description. DNA-barcoding campaigns are rapidly developing in soil animals and the community of soil biologists is urged to embrace these methods.

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On Chichijima, one of the Ogasawara (Bonin) Islands located in the Western Pacific Ocean, land snails have declined, the suggested cause being predation pressure by an invasive flatworm (Platydemus manokwari). Soil fauna were investigated in areas where the snail survives, and where it has become extinct. Much of the fauna, dominated by introduced earthworms and ants, was undiminished, however, one undescribed but endemic carabid (Badister sp.), which selectively feeds on land snails, was absent in snail-extinct areas. The invasive flatworm P. manokwari has been reported to feed also on the carcasses of earthworms, as well as on live snails, and is therefore expected to occur in most parts of Chichijima Island. Among other groups, the density of isopods (also dominated by exotic species) was very low, in comparison with the reported ones 30 years ago. Community structure is currently reflected by dominance of earthworms and ants, decline of endemic isopods, and a high frequency of introduced or alien species.