2,160 research outputs found

    The mycorrhizal status of Phragmites australis in several polluted soils and sediments of an industrialised region of Northern Portugal

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    Roots of Phragmites australis from three polluted soils and sediments (a periodically flooded stream bank containing organic pollutants, a high-pH drying sedimentation pond and an acidic, periodically flooded sand polluted by industrial effluents) were sampled over a 1-year cycle of plant growth to assess the degree of colonisation by arbuscular mycorrhizal fungi (AMF). At the dry sedimentation pond, root samples of Juncus effusus and Salix atrocinerea were also taken to assess the presence of AMF throughout the year. Root colonisation was low (<5% root length colonised) but arbuscule presence peaked in P. australis during the spring and autumn prior to flowering. These changes in arbuscule abundance were also seen in a parallel greenhouse trial using seed taken from one of the sites. Roots of J. effusus contained mainly vesicular colonisation but arbuscule activity peaked during the winter months (December–March). S. atrocinerea roots were found to be ectomycorrhizal throughout the year but the fine feeder roots were colonised by AMF. The results confirm that semi-aquatics, like P. australis, can become arbuscular mycorrhizal but that this status changes during the year depending on soil moisture content and plant phenology. The influence of AMF in these polluted soils is uncertain but the potential exists to establish a more diverse plant ecosystem during the landscaping of these areas (phytostabilisation) by management of adapted plant and AMF ecotypes

    Productive aspects of pigs fed forage cactus silage associated with feed restriction

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    This study aimed to evaluate the use of silage of forage cactus (Opuntia ficus-indica Mill) in diets for finishing pigs. Two experiments were conducted: the first for digestibility and the second for performance. In the performance trial, the quantitative levels of feed restriction (0%, 10%, 20%, and 30%) were evaluated, which were associated with the supply of forage cactus silage. Forage cactus silage presented 2463.59 and 2456 kcal/kg of digestible and metabolizable energy, respectively. The feed restriction levels associated with the supply of forage cactus silage influenced feed intake, weight gain and final weight negatively, but did not affect feed conversion. Carcass absolute weight was influenced negatively. However, the yield of carcass and cuts and the amount of meat in the carcass were not influenced. With the increase in feed restriction, there was a decrease in duodenal mucosa thickness, intestinal glands, liver glycogen storage and the occurrence of inflammation in the submucosa and intestinal mucosa. Forage cactus silage is not accepted well by animals. The restriction up to 30% of balanced feed did not affect feed conversion, yield of carcass and cuts and economic viability. However, levels over 10% affected intestinal health.Keywords: Alternative feed, feed preservation, intestinal health, Opuntia ficus-indica Mill, pig nutritio

    Survey Of Acarin Fauna In Dust Samplings Of Curtains In The City Of Campinas, Brazil.

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    The aim of this study was to investigate the mite fauna present in 33 living room and 22 bedroom curtain dust samples from 41 different homes in the southern Brazilian city of Campinas, SP. A total of 148 mite bodies were found. Of these, 83 were found in living-room curtain samples (56.1% of total) and 65 were in bedroom curtain dust samples (43.9%). The most frequently observed mite suborders were: Acaridida (n = 79; 53.4%), Actinedida (n=53; 35.8%), Oribatida (n=14; 9.5%), and Gamasida (n=2; 1.3%). The most frequent families were Pyroglyphidae (n=61; 41.2%), Eriophyidae (n=25; 16.9%), Tarsonemidae (n=15; 10.1%), and Glycyphagidae (n=13; 8.8%). No statistical difference was observed between the number of mites found in the samples from living room and bedroom curtains.651252

    Laser deposition of alumina and carbon black on AISI 4340 steel

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    In the present work, a laser beam was used to cover, with graphite (solid lubricant material) mixed with alpha alumina (a-Al2O3), surfaces samples of AISI 4340 steel. The proportion of each component used was 50%, mixed in a planetary ball mill for 2 hours. A CO2 laser beam of 125 W and 0.2 mm beam diameter was used to irradiate the samples previously coated with the powders. The reduced friction of the mechanical part was confirmed by a tribo-tester in a reciprocal mode. Friction near to 0.15 was obtained with substrate steel hardened to 900 Hv with a ceramics top coating.The authors acknowledge CNPq (National Research Council) and FAPESP (Research Foundation of the São Paulo State) by financial support

    Cognitive approaches and optical multispectral data for semi-automated classification of landforms in a rugged mountainous area

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    This paper introduces a new open source, knowledge-based framework for automatic interpretation of remote sensing images, called InterIMAGE. This framework owns a flexible modular architecture, in which image processing operators can be associated to both root and leaf nodes of the semantic network, which constitutes a differential strategy in comparison to other object-based image analysis platforms currently available. The architecture, main features as well as an overview on the interpretation strategy implemented in InterIMAGE is presented. The paper also reports an experiment on the classification of landforms. Different geomorphometric and textural attributes obtained from ASTER/Terra images were combined with fuzzy logic and drove the interpretation semantic network. Object-based statistical agreement indices, estimated from a comparison between the classified scene and a reference map, were used to assess the classification accuracy. The InterIMAGE interpretation strategy yielded a classification result with strong agreement and proved to be effective for the extraction of landforms

    MUMAL: multivariate analysis in shotgun proteomics using machine learning techniques.

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    BACKGROUND: The shotgun strategy (liquid chromatography coupled with tandem mass spectrometry) is widely applied for identification of proteins in complex mixtures. This method gives rise to thousands of spectra in a single run, which are interpreted by computational tools. Such tools normally use a protein database from which peptide sequences are extracted for matching with experimentally derived mass spectral data. After the database search, the correctness of obtained peptide-spectrum matches (PSMs) needs to be evaluated also by algorithms, as a manual curation of these huge datasets would be impractical. The target-decoy database strategy is largely used to perform spectrum evaluation. Nonetheless, this method has been applied without considering sensitivity, i.e., only error estimation is taken into account. A recently proposed method termed MUDE treats the target-decoy analysis as an optimization problem, where sensitivity is maximized. This method demonstrates a significant increase in the retrieved number of PSMs for a fixed error rate. However, the MUDE model is constructed in such a way that linear decision boundaries are established to separate correct from incorrect PSMs. Besides, the described heuristic for solving the optimization problem has to be executed many times to achieve a significant augmentation in sensitivity. RESULTS: Here, we propose a new method, termed MUMAL, for PSM assessment that is based on machine learning techniques. Our method can establish nonlinear decision boundaries, leading to a higher chance to retrieve more true positives. Furthermore, we need few iterations to achieve high sensitivities, strikingly shortening the running time of the whole process. Experiments show that our method achieves a considerably higher number of PSMs compared with standard tools such as MUDE, PeptideProphet, and typical target-decoy approaches. CONCLUSION: Our approach not only enhances the computational performance, and thus the turn around time of MS-based experiments in proteomics, but also improves the information content with benefits of a higher proteome coverage. This improvement, for instance, increases the chance to identify important drug targets or biomarkers for drug development or molecular diagnostics

    Effect of raw sugar cane bagasse on performance and ingestive behavior of beef cattle

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    Avaliou-se o efeito da utilização do bagaço de cana-de-açúcar in natura (BIN), obtido por dois métodos de extração do açúcar, moagem convencional ou difusão, como fonte de fibra em dietas que continham bagaço tratado sob pressão e vapor (BTPV), como principal fonte de volumoso sobre o desempenho e o comportamento ingestivo de bovinos confinados. Para avaliação do desempenho, foram utilizados 84 machos não castrados das raças Nelore, Canchim e Holandesa, com média de peso inicial de 270kg, distribuídos em delineamento de blocos ao acaso. Para a avaliação do comportamento ingestivo, foram utilizados quatro garrotes da raça Nelore, em delineamento de quadrado latino 4 x 4. Os tratamentos consistiram na substituição do BTPV pelo BIN na matéria seca, constituindo as dietas experimentais: 5% BIN moagem convencional; 5% BIN difusão, 10% BIN difusão e 15% BIN difusão. O consumo de MS foi menor no tratamento com 15% de BIN obtido por difusão (BINdif), em relação ao teor de inclusão de 10%. Não houve diferença (P>0,05) entre os tratamentos para ganho diário de peso, conversão alimentar e peso vivo final entre os tratamentos. Os tempos despendidos com as atividades de ruminação (minutos/kg de MS) e mastigação (minutos/kg de MS ou de FDN) foram maiores (P<0,05) no tratamento com 15% de BINdif na dieta. O BINdif pode ser utilizado como fonte de fibra íntegra em até 15% da MS da dieta sem prejudicar o desempenho dos animais.This study was conducted to evaluate effects of replacing steam pressure treated sugar cane bagasse by two types of raw sugar cane bagasse extracted through grinding or diffusion, on performance and ingestive behavior of beef cattle. Eighty four young bulls (Nelore, Canchim and Holstein) with 270kg of body weight at the beginning of the experiment were used in a randomized block design. Ingestive behavior was evaluated using four Nelore young bulls in a 4 x 4 Latin square design. Treatments were the direct substitution of steam pressure treated sugarcane bagasse by raw bagasse (RB), corresponding to the experimental treatments: 5% RB from grinding; 5% RB from diffusion; 10% RB from diffusion and 15% RB from diffusion. Dry matter intake was lower in treatment with 15% of bagasse obtained by diffusion (BINdif) in comparison to 10% BINdif. There were no differences (P>0.05) among treatments for average daily gain, feed conversion and final live weight. Ruminating time (minutes/kg of DM) and chewing time (minutes/kg of DM or NDF) was greater (P>0.05) when BINdif was added at 15% level to diets. BINdif can be added up to 15% of the dietary DM with no detrimental effect on beef cattle performance
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