204 resultados para Orthogonal polynomials in two variables


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OBJETIVO: Realizou-se um inquérito para comparar diferenças de gênero nos padrões de consumo de álcool em duas amostras urbanas, estratificadas e representativas de duas comunidades (B e RJr). MÉTODO: O questionário Genacis (Gênero, Álcool e Cultura: Um Estudo Internacional Gender, Alcohol, and Culture: An Internacional Study) foi utilizado. RESULTADOS: Houve várias diferenças significativas em dados sociodemográficos e de padrões de uso de álcool entre essas duas amostras. Uma delas tinha população mais velha, educada, católica, branca e mais mulheres na força de trabalho. Dados da comunidade B mostraram que mulheres e homens tiveram padrões similares de consumo de álcool. RJr teve uso de álcool mais alto entre homens e 22% dos homens abaixo de 49 anos de idade tinham padrão de uso do tipo binge. DISCUSSÃO: O acesso, tabagismo, renda e ter um parceiro com consumo pesado de álcool foram fatores de risco importantes para o consumo das mulheres. CONCLUSÕES: Este estudo mostra que quando os papéis das mulheres se tornam similares aos dos homens, modificam seu padrão de consumo de álcool.

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The establishment of plants depends crucially on where seeds are deposited in the environment. Some authors suggest that in forest understory seed predation is lower than in gaps, and higher than at the forest edge. However, most studies have been carried out in large forest patches and very little is known about the effects of microhabitat conditions on seed predation in forest fragments. We evaluated the effects of three microhabitats (gaps, forest edge, and understory) on seed predation of two palm species (Euterpe edulis and Syagrus romanzoffiana) in two semi-deciduous forest fragments (230 and 2100 hat in southeast Brazil. Our objective was to test two hypotheses: (1) Low rodent abundance in small fragments as a result of meso-predator action levels leads to lower seed predation in small fragments. (2) Most mammal species in small fragments are generalists with respect to diet and habitat, so that seed predation is similar in different microhabitats (gaps, forest edge and understory) in the small fragment, but not in the larger one. The study community of small fragments is usually composed of generalist species (in diet and habitat aspects), so we expected the same rate of seed predation among microhabitats (gaps, forest edge and understory) in the tested smaller fragment. The experiment was carried out in the dry season (for E. edulis) and in the wet season (for S. romanzoffiana) in 1999. We conclude that post-dispersal seed predation in forest fragments can be directly connected with mammal communities, reflecting their historical and ecological aspects. (C) 2004 Elsevier SAS. All rights reserved.

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We show how symmetric orthogonal polynomials can be linked to polynomials associated with certain orthogonal L-polynomials. We provide some examples to illustrate the results obtained Finally as an application, we derive information regarding the orthogonal polynomials associated with the weight function (1 + kx(2))(1 - x(2))(-1/2), k > 0.

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Evaporative water loss (EWL) and oxygen uptake ((V) over dot o(2)) was measured in two species of tree frogs with cranial co-ossification, Aparasphenodon brunoi and Corythomantis greeningi. Both species use their head to seal the entrance of bromeliads, tree holes or rocky crevices used as shelters. EWL was significantly reduced in sheltered individuals of both species as compared with those exposed nude to desiccation. EWL per unit area through the head surface was significantly lower than the body skin for A. brunoi but not for C., greeningi. EWL per unit surface area through C. greeningi body skin was about 50% that of A. brunoi, indicating a less permeable skin in the former species. The relationship between cranial coossification and EWL is discussed. ((V) over dot o(2)) in A. brunoi was comparable with other anurans of similar size, whereas in C. greeningi, it was lower than predicted from body mass. Moreover, ((V) over dot o(2)), in C. greeningi showed less sensitivity to temperature increase than in A. brunoi. C. greeningi occurs in a drier environment than A. brunoi, and this appears to be reflected in their EWL and ((V) over dot o(2)) characteristics. (C) 1997 Elsevier B.V.

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Using the integrability conditions that we recently obtained in two-dimensional QCD with massless fermions we arrive at a sufficient number of conservation laws to fix the scattering amplitudes involving a local version of the Wilson loop operator.

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Cashew apple nectar is a secondary product from the production of cashew nuts and possesses an exotic tropical aroma. Aroma volatiles in pasteurized and reconstituted (from concentrate) Brazilian cashew apple nectars were determined using GC-MS and split, time-intensity GC-olfactometry (GC-O/GC-FID. Methional, (2)-1,5-octadien-3-one, (2)-2-nonenal, (E,Z)-2,4-decadienal, (E,E)-2,4-decadienal, beta-damascenone, and delta-decalactone were identified for the first time in cashew apple products. These compounds plus butyric acid, ethyl 3-methylbutyrate, 2-methylbutyric acid, acetic acid, benzaldehyde, homofuraneol, (E)-2-nonenal, gamma-dodecalactone, and an unknown were the most intense aroma volatiles. Thirty-six aroma volatiles were detected in the reconstituted sample and 41 in the pasteurized sample. Thirty-four aroma active components were common to both samples. Ethyl 3-methylbutyrate and 2-methylbutyric acid were character impact compounds of cashew apple (warm, fruity, tropical, sweaty). Using GC-pFPD, 2-methyl-3-furanthiol and bis(2-methyl-3-furyl) disulfide were identified for the first time in cashew apple. Both were aroma active (meaty).

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This paper deals with the classes S-3(omega, beta, b) of strong distribution functions defined on the interval [beta(2)/b, b], 0 < beta < b <= infinity, where 2 omega epsilon Z. The classification is such that the distribution function psi epsilon S-3(omega, beta, b) has a (reciprocal) symmetry, depending on omega, about the point beta. We consider properties of the L-orthogonal polynomials associated with psi epsilon S-3(omega, beta, b). Through linear combination of these polynomials we relate them to the L-orthogonal polynomials associated with some omega epsilon S-3(1/2, beta, b). (c) 2004 Elsevier B.V. All rights reserved.

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Modification showed by intertidal macrofaunal communities between two nearby sites that change from a wave to a tide dominated beach environment, was analyzed on the present study. At each site, eleven intertidal sampling stations were distributed along a transect, from the drift line to the spring low tide water level. Four macrofaunal samples one meter long-shore spaced were collected at, each station with an iron core of 0.05 m(2) surface area, taken to a depth of 20 cm. Major,differences on sediments between sites were the offshore decrease of mean particle size diameter and increase of kurtosis and water content at the tide dominated site. KIDS ordination showed major similarities between the lowest stations of this site, that represents the dissipative low tide-terrace portion of the beach. Two lower station of the wave dominated site presented similarities with this group. The other stations of the tide-dominated site, that represents the reflective high tide beach portion, grouped distant from the former. (canonical Correspondence Analysis (CCA) showed a similar spatial distribution of stations, suggesting the importance of environmental factors on the explanation of species distribution patterns. Sediment water content and water table depth, with the highest inertia value, seems to be the principal physical factor. Increase on water content affects the macrofaunal distribution by the expansion of typical infralitoral species, as was the case of Bathyporeiapus ruffoi, on the dissipative low tide terrace beach portion. A disrupted distribution with the lost of a gradate zonation along a physical gradient is one of the major modification presented by macrobenthic communities on the transition from a wave to a tide dominated beach environment.

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Genetic analyses of sex determination have identified sex chromosomes in many teleost fish species. However, there are several cases for which sex ratios do not fit perfectly with the expectations of heterogametic systems, suggesting the influence of either minor sex determining genes or environmental influences on the process of sex differentiation. The frequent absence of sex chromosome markers makes the identification of minor sex-determining genes very difficult. It is easier to test first the hypothesis of environmental sex determination (ESD) by studying the temperature effect, since temperature-dependent sex determination has been demonstrated to occur in several vertebrate groups including 1 fish species. To contribute to a better understanding of fish sex determination, we have tested the effects of high temperatures on sex ratios of Oreochromis niloticus, and have attempted to isolate sex chromosome molecular markers in Leporinus elongatus. Treatments of O. niloticus fry at 36 degrees C applied for 10 days and more, and starting 1 week after fertilization markedly increased the proportion of males, and progeny-testing these males confirmed that some of them are sex-reversed genetic females. Two non-coding sequences of L. elongatus Z and W chromosomes were cloned by genomic subtraction. They cross-hybridized with the genome of a close species without providing sex-specific patterns. A collection of L. elongates individuals was subjected to gonadal and chromosomal sexing, and DNA hybridization with both sequences. These analyses revealed 3 individuals having atypical W chromosomes. Interestingly, 2 of these were males having a ZW karyotype. We assume that these atypical sex chromosome arise by exchanges between Z and W chromosomes, and that a transition between female and male heterogamety is underway in this species.

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The external infestation of Callinectes ornatus Ordway, 1863 and Callinectes danae Smith, 1869, in particular cirripeds, was studied for two consecutive years in the Ubatuba Bay (SP) (23 degrees 26' S and 45 degrees 02' W). Bryozoans, polychaetes and cirripeds were found on both swimming crab species, but cirripeds were the most abundant and frequent. The number of infested swimming crabs increased proportionally to carapace size, but not surpassing 30 %, suggesting an absence of terminal anecdysis in both species. The establishment of the pernicious organisms on their hosts is influenced by other factors, such as their habit of burying themselves in sediments. The correlation between molting activity in adult specimens of both sexes and the low incidence of epizoonts suggest that C. ornatus and C. danae may be molting after maturity.

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Morphometric and colour pattern variation in the endemic Iberian salamander Chioglosso lusitanica is concordant with the genetic differentiation of two groups of populations separated by the Mondego river ill Portugal. Salamanders from the south have shorter digits than those from the north. Clinal variation with a south to north increase in limb. toe and finger length was found superiniposed on this dichotomy resulting in stepped clines for characters describing appendage size. Genetic variability was paralleled by colour pattern variability in the contact zone and in northern populations. To explain the observed parallels we invoke the neutral processes of vicariant isolation. admixture in a secondary contact zone, genetic drift in addition to selection acting along all environmental gradient. Morphological constraints imposed by a highly specialized ecological niche may explain why the genetic subdivision of C. lusitanica since the early, Pleistocene has remained fairly cryptic.