947 resultados para trapping effort
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Adjusted mean catches which are calculated discounting the effect of average fishing effort increase the further the lake is from Manaus, Brazil. -from Author
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Thin films of undoped and Sb-doped (2 atg%) SnO2 have been prepared by sol-gel dip-coating technique on borosilicate glasses. Variation of photoconductivity excitation with wavelength and optical absorption indicate indirect bandgap transition with energy of ≅ 3.5 eV. Conductance as function of temperature indicates two levels of capture with 39 and 81 meV as activation energies, which may be related to an Sb donor and oxygen vacancy respectively. Electron trapping by these levels are practically destroyed by UV photoexcitation (305 nm) and heating in vacuum to 200°C. Gas analysis using a mass spectrometer indicates an oxygen related level, which may not be desorbed in the simpler O2 form.
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The atomic tunneling between two tunnel-coupled Bose-Einstein condensates (BECs) in a double-well time-dependent trap was studied. For the slowly varying trap, synchronization of oscillations of the trap with oscillations of the relative population was predicted. Using the Melnikov approach, the appearance of the chaotic oscillations in the tunneling phenomena between the condensates was confirmed.
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The main method used for the control of gastrointestinal nematodes in sheep production is the application of chemotherapeutic agents, which often lead to the selection of parasites resistant to given active principles. Biological control can be considered a promising alternative, contributing to an increase in the efficacy of verminous control. We determined the in vitro activity and in situ survival of the predatory fungi Arthrobotrys musiformis and Arthrobotrys conoides during passage through the gastrointestinal tract of sheep after oral administration of conidia in microencapsulated form and as a liquid in natura. Initial in vitro tests showed that both fungi were efficient in the predation of trichostrongylid L3 larvae present in the faeces of sheep naturally infected with gastrointestinal nematodes. The fungi presented high nematophagous activity, which was 99.3% for A. conoides and 73.7% for A. musiformis. A. conoides did not survive passage through the gastrointestinal tract under the conditions of the present experiment. On the other hand, A. musiformis was reisolated after administration in either microencapsulated or liquid form, suggesting that this species is a promising alternative for the control of nematodes in sheep since it survives without any protection (in natura). © Springer 2005.
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Alteration of the occlusion and the position of the jaw can affect the muscles of the neck, due to a relationship between the masticatory and cervical systems. Thus, the objective of this study was to verify whether the bite in maximal clenching effort, in centric occlusion, in individuals with clinically normal occlusion, and without a history of dysfunction in the masticatory system, influences the electromyographic activity of the upper trapezius muscle. A total of 19 normal individuals participated in the study, 14 of which were women (average age of 25.4 ± 4.14 years), and 5 were men (average age of 24.11 ± 3.28 years). The root mean square (RMS) amplitude and median frequency (MF) of the upper trapezium muscle with 40% and 60% of maximal voluntary contraction were analyzed under pre- and post-maximal clenching effort conditions in centric occlusion. The electromyographic signal was collected with a sampling frequency of 2. kHz and the value in RMS was obtained by a moving window of 200. ms. The paired Student's t-test was used to compare RMS amplitude and MF under pre- and post-maximal clenching effort conditions. The level of significance for each comparison was set to p<0.05. This study concluded that in individuals without a history of dysfunction of the masticatory system, maximum clenching effort in centric occlusion does not alter the electromyographic signal of the upper trapezius. © 2009 Elsevier Ltd.
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Parental effort may influence the fitness and survivorship of adult birds and their offspring from one breeding season to the next. Although much is known about parental feeding effort in tyrant flycatchers, many species remain understudied. In this study, I examined parental feeding effort of the White-headed Marsh-Tyrant (Awndinicola leucocephala) at a pond in southeastern Brazil. I conducted 10.3 hrs of observations from two locations: a high place with all view of the whole pond, that allowed me to observe flight distances of parents hunting for prey; and from near the nest to observe frequency of visits to the nest. The female marsh-tyrant flew farther while hunting prey and made more visits to the nest than did the male. The adults (mainly the female) provided a variety of terrestrial and aquatic arthropods to the nestlings. Additionally, parents removed fecal sacs from the nest and nestlings eliminated arthropod remains from the nest, the first records of nest sanitation activities by this species. Nonexclusive hypotheses that may explain the lower level of parental care provided by the male include: higher predation risk due its more conspicuous plumage, commitment of male to territory defense, and its selfish behavior influenced by indirect genotype fitness inherited by the offspring. © The Neotropical Ornithological Society.
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Eigenstates of a particle in a localized and unconfined harmonic potential well are investigated. Effects due to the variation of the potential parameters as well as certain results from asymptotic expansions are discussed. © 2012 Springer Science+Business Media, LLC.
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We show that self-localized ground states can be created in the spin-balanced gas of fermions with repulsion between the spin components, whose strength grows from the center to periphery, in combination with the harmonic-oscillator (HO) trapping potential acting in one or two transverse directions. We also consider the ground state in the noninteracting Fermi gas under the action of the spatially growing tightness of the one- or two-dimensional (1D or 2D) HO confinement. These settings are considered in the framework of the Thomas-Fermi-von Weizsäcker (TF-vW) density functional. It is found that the vW correction to the simple TF approximation (the gradient term) is nearly negligible in all situations. The properties of the ground state under the action of the 2D and 1D HO confinement with the tightness growing in the transverse directions are investigated too for the Bose-Einstein condensate with the self-repulsive nonlinearity. © 2013 American Physical Society.
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Introduction: The literature lacks studies about lactate actions and some limitations in studies involving healthy individuals or patients with some metabolic disorder. Objectives: This study aimed to evaluate the protocol of double effort test for obese-induced rats. Methods: Fourteen male Wistar rats were divided into two groups: Control (Con) and Obese (Obe). The control group was fed with standard chow and water ad libitum. The obese group was fed with standard chow, water ad libitum and hyperlipidic diet. Twelve weeks after the beginning of the hyperlipidic diet, insulin tolerance test, Maximal Lactate Steady State (MLSS) test and the double efforts test were performed. Results: The diet was effective to promote obesity. The obese group decreased insulin sensitivity in approximately 19% (Con = 2.156 ± 0.1187 AU vs Obe = 1.742 ± 0.1551 AU). The lactate concentration and velocity of anaerobic threshold at MLSS test were 3.780 ± 0.09 mmol/L e 18 m.min-1 in both groups. The velocity of anaerobic threshold estimated by double efforts test was 15.59±0.653 m.min-1 in Con group control animals and 16.42±0.672 m.min-1 in Obe group. The double effort test underestimated around 13% and 8.7% the aerobic capacity in control and obese groups respectively, however, presented significant correlation with MLSS (r = 0,88; P < 0,0075 controls / r = 0,92; P < 0,0031 obese). Conclusion: So, the double effort test can be an interesting alternative to evaluate the aerobic capacity for both healthy sedentary and obese animals.
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Incluye Bibliografía
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As borboletas do grupo Ithomiinae são caracterizadas por espécies estritamente neotropicais, consideradas modelos de anéis miméticos e apresentam uma taxonomia relativamente bem conhecida. Por estas razões são frequentemente utilizadas como indicadores biológicos. O presente estudo teve como intuito caracterizar a comunidade de Ithomiinae em uma área de Floresta Ombrófila Densa (terra firme), localizada na Estação Científica Ferreira Penna (Floresta Nacional de Caxiuanã), município de Melgaço, estado do Pará, além de testar a eficiência do protocolo de captura deste grupo. Para isto foram realizadas coletas em uma área de 500 x 500 m, utilizando dois métodos. O primeiro foi o de armadilhas contendo isca de folhas e inflorescências de Heliotropium indicum dentro de cinco parcelas amostrais de 100 x 100 m, sendo que cada uma continha cinco pares de armadilhas (uma sub-bosque e outra no dossel da floresta). O outro método foi o de coletas com redes entorno lógicas entre as parcelas. O período da amostragem foi nos meses de julho, outubro de 2004 e janeiro a novembro de 2005 (cinco dias de coleta mensais). Com um esforço total de 2000 armadilha horas por mês e 40 redes horas por mês foram registrados 1844 indivíduos de Ithomiinae, pertencentes a 14 espécies. As espécies Hypothyris ninonia (Hübner, [1806]) e Napeogenes rhezia (Geyer, [1834]) foram as espécies mais abundantes. Foi encontrada uma diversidade homogênea tanto no sentido horizontal quanto vertical, apesar de ser observada uma preferência da maioria das espécies pelo ambiente de sub-bosque. Foi registrada uma predominância de machos na comunidade da área. Como o grupo apresenta diferenças comportamentais entre indivíduos machos e fêmeas, essa predominância de machos nos registros pode ser resultado de uma seleção dos métodos na captura dos espécimes. Não foi encontrada uma diferença significativa entre a riqueza de espécies registrada pelos diferentes métodos, apesar de três espécies serem obtidas exclusivamente pelas redes, e outras duas pelas armadilhas de isca. Houve uma predominância nos registros de Methona sp. pelas redes entomológicas, sugerindo uma atração diferenciada da espécie pela isca utilizada. Verificou-se uma correlação negativa entre o número de indivíduos coletados e o aumento dos índices de pluviosidade. O estudo apresentou uma baixa riqueza de espécies com amostragem intensiva, a comunidade é representada por espécies abundantes e raras; e apresenta oscilações na abundância conforme a precipitação pluviométrica. As armadilhas de sub-bosque foram mais eficiente. Sugere-se para Ithomiinae a utilização de somente armadilhas no subbosque com isca de Heliotropium indicum.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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In this note we demonstrate that the use of an index to standardize the fishing effort using the cpue of a standard vessel or gear is mistaken, once the cpues- catch per unit of total effort after standardization is similar to cpues - catch per unit of effort of the standard vesel or gear arbitrarily chosen.