43 resultados para litter trap

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


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Eucalyptus spp. plantations represent >60% of the reforested area in Brazil. Although ambrosia beetle attacks on live trees were at first nonexistent, they have begun to appear with greater frequency. Monitoring for pest insects is a key factor in integrated pest management, and baited traps are one of the most widely used methods for insect population detection and survey. We compared the efficiency of the most widely used trap in Brazil to survey for ambrosia beetles and other Scolytidae, the ESALQ-84 type, with other traditionally employed traps: the multiple funnel (Lindgren trap); drainpipe; and slot (Theyson) traps, in a Eucalyptus grandis Hill ex Maiden stand in Brazil. The ESALQ-84 trap was the most efficient in trapping Hypothenemus eruditus Westwood and Hypothenemus obscurus (F.); the multiple funnel trap caught significantly more Cryptocarenus diadematus Eggers; whereas the slot trap caught more Premnobius cavipennis Eichhoff and Xyleborus affinis Eichhoff than the other traps. The drainpipe trap was the least effective trap overall. When corrected for number of beetles caught per trap surface area, catches were significantly higher on the ESALQ-84 trap for the majority of the species analyzed, probably because of a smaller trap surface area. The slot trap was recommended for it caught overall more beetles of the three most economically important scolytid species in eucalypt plantations in Brazil, P. cavipennis, X. affinis, and X, ferrugineus.

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A fauna de Ephemeroptera, Plecoptera e Trichoptera associadas ao folhiço em um riacho do sudeste do Brasil foi estudada com o objetivo de responder às seguintes questões: 1) A riqueza e a composição faunística de EPT difere entre os dois mesohabitats (corredeira-remanso) mesmo quando associadas ao mesmo substrato, folhiço? 2) A similaridade da fauna de EPT entre os dois mesohabitas muda temporalmente? 3) A estrutura funcional de EPT difere entre os dois mesohabitats (corredeira-remanso)? Para responder essas questões, coletas mensais, de novembro de 1999 a junho de 2000, foram feitas no Ribeirão Bocaina com rede D (10 acúmulos de folhas em remanso e 10 em corredeira). A fauna de EPT do Ribeirão Bocaina foi mais diversificada e mais abundante no folhiço em corredeira do que no folhiço em remanso, no entanto, quando a riqueza foi padronizada para o mesmo número de indivíduos essa se tornou similar para as duas condições. A fauna de EPT foi bastante diferente entre os dois mesohabitats, tanto em termos da composição faunística quanto em termos funcionais. Isso provavelmente ocorreu devido às diferenças de velocidade da água, no tempo de residência do folhiço e na taxa de oxigênio da água entre os dois mesohabitats.

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Workplace accidents involving machines are relevant for their magnitude and their impacts on worker health. Despite consolidated critical statements, explanation centered on errors of operators remains predominant with industry professionals, hampering preventive measures and the improvement of production-system reliability. Several initiatives were adopted by enforcement agencies in partnership with universities to stimulate production and diffusion of analysis methodologies with a systemic approach. Starting from one accident case that occurred with a worker who operated a brake-clutch type mechanical press, the article explores cognitive aspects and the existence of traps in the operation of this machine. It deals with a large-sized press that, despite being endowed with a light curtain in areas of access to the pressing zone, did not meet legal requirements. The safety devices gave rise to an illusion of safety, permitting activation of the machine when a worker was still found within the operational zone. Preventive interventions must stimulate the tailoring of systems to the characteristics of workers, minimizing the creation of traps and encouraging safety policies and practices that replace judgments of behaviors that participate in accidents by analyses of reasons that lead workers to act in that manner.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The aim of this study was to evaluate the effects of different litter materials on litter compaction, broiler feathering and the incidence of carcass lesions. In the experiment, 3240 one-day-old Ross® chicks were selected by sex and distributed according to a completely randomized experimental design in a 2 x 6 factorial arrangement (two sex and six litter materials). The following litter materials were used: wood shavings, rice husks, chopped Napier grass, 50% sugar cane bagasse plus 50% wood shavings, 50% sugar cane bagasse plus 50% rice husks, and pure sugar cane bagasse. Litter compaction was weekly assessed using a penetrometer. on days 21, 35 and 42 of the experimental period, feathering on the back and legs was scored according to a 0 - 10 scale. on day 42, birds were slaughtered and the presence of bruises, scratches and footpad lesions was recorded. Litter material had no effect on bird feathering. Carcass lesions (scratches, bruises and footpad lesions) were influenced by the litter material evaluated. Birds reared on sugarcane bagasse and chopped Napier grass presented more scratches, bruises and footpad lesions than the others. Dermatitis was more evident in birds reared on sugarcane bagasse, chopped Napier grass and the combination of litter materials. It was found that males presented higher incidence of dermatitis and footpad lesions than females. Each litter material presented different compaction degrees, which increased along the experimental period. Sugarcane bagasse, chopped Napier grass and the combination of bedding materials presented the highest degree of compaction, compared with wood shavings and rice husks.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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This study aimed to analyze the species composition and functional groups of the ant community and to assess the efficiency of two sampling methods, pitfall and leaf litter sampling, in an urban park. A total of 1,401 ants were collected, which belonged to six subfamilies and 36 species. The predominant species was Wasmannia auropunctata (present in 45.36% of the samples), while the functional group of opportunistic ants were the most frequent (present in 83.75% of the samples) and abundant (95.29% of the total collected specimens) functional group. The Jaccard Similarity Index showed a low similarity between the two sampling methods, as the difference of the number of individuals for each species between these two methods was not significant in only one case (Linepithema sp. 1, p = 0.4561). The fungus-growing and cryptic ants were more collected in leaflitter samples (p<0.0001; p = 0.0348 respectively). Although there was no significant difference (p = 0.6397) between the two sampling methods for the total individuals of opportunistic ants, more species of this group were collected in pitfall traps. This difference was not significant because of the high presence of W. auropunctata, an opportunistic ant, in samples of leaf litter. Due to the predominance of tramp ants in the studied area, this article illustrates the importance of green urban areas in ant control strategies, since these sites could be used as a source of new colonization for these ants. Furthermore, the combination of the two sampling methods seems to be complementary for obtaining a more complete picture of the ant community.

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Using the axially-symmetric time-dependent Gross-Pitaevskii equation we study the phase coherence in a repulsive Bose-Einstein condensate (BEC) trapped by a harmonic and an one-dimensional optical lattice potential to describe the experiment by Cataliotti et al. on atomic Josephson oscillation [Science 293, 843 (2001)]. The phase coherence is maintained after the BEC is set into oscillation by a small displacement of the magnetic trap along the optical lattice. The phase coherence in the presence of oscillating neutral current across an array of Josephson junctions manifests in an interference pattern formed upon free expansion of the BEC. The numerical response of the system to a large displacement of the magnetic trap is a classical transition from a coherent superfluid to an insulator regime and a subsequent destruction of the interference pattern in agreement With the more recent experiment by Cataliotti et al. [New J. Phys. 5, 71 (2003)].

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Based on the time-dependent Gross-Pitaevskii equation we study the evolution of a collapsing and exploding Bose-Einstein condensate in different trap symmetries to see the effect of confinement on collapse and subsequent explosion, which can be verified in future experiments. We make a prediction for the evolution of the shape of the condensate and the number of atoms in it for different trap symmetries (cigar to pancake) as well as in the presence of an optical lattice potential. We also make a prediction for the jet formation in different cases when the collapse is suddenly terminated by changing the scattering length to zero via a Feshbach resonance. In addition to the usual global collapse to the center of the condensate, in the presence of an optical-lattice potential one could also have in certain cases independent collapse of parts of the condensate to local centers, which could be verified in experiments.

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Using the mean-field time-dependent Gross-Pitaevskii equation we study the formation of a repulsive Bose-Einstein condensate on a combined optical and harmonic traps in two and three dimensions and subsequent generation of the interference pattern upon the removal of the combined traps as in the experiment by, Greiner et al. [Nature (London 415 (2002) 39]. For optical traps of moderate strength, interference pattern of 27 (9) prominent bright spots is found to be formed in three. (two) dimensions on a cubic (square) lattice in agreement with experiment. Similar interference pattern can also be formed upon removal of the optical lattice trap only. The pattern so formed can oscillate for a long time in the harmonic trap which can be observed experimentally. (C) 2003 Elsevier B.V. B.V. All rights reserved.

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Considering the static solutions of the D-dimensional nonlinear Schrodinger equation with trap and attractive two-body interactions, the existence of stable solutions is limited to a maximum critical number of particles, when D greater than or equal to 2. In case D = 2, we compare the variational approach with the exact numerical calculations. We show that, the addition of a positive three-body interaction allows stable solutions beyond the critical number. In this case, we also introduce a dynamical analysis of the conditions for the collapse. (C) 2000 Published by Elsevier B.V. B.V. All rights reserved.

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The quantized vortex states of a weakly interacting Bose-Einstein condensate of atoms with attractive interatomic interaction in an axially symmetric harmonic oscillator trap are investigated using the numerical solution of the time-dependent Gross-Pitaevskii equation obtained by the semi-implicit Crank-Nicholson method. The collapse of the condensate is studied in the presence of deformed traps with the larger frequency along either the radial or the axial direction. The critical number of atoms for collapse is calculated as a function of the vortex quantum number L. The critical number increases with increasing angular momentum L of the cortex state but tends to saturate for large L.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)