965 resultados para Floristic Similarity
Resumo:
This paper reports an investigation into the antecedents of commitment in non-Western industrial marketing relationships. The authors draw the antecedents from extant literature and posit that commitment is related to trust (integrity and reliability), communication quality, conflict, and similarity (social, ethnic, and economic). It is further argued that trust mediates the effects of communication, conflict, and similarity on commitment. As an extension, the authors examine the moderating effects of normative contracts (an implicit understanding of roles and responsibilities) on the construct interrelationships. The hypotheses are tested using data collected from approximately 150 industrial marketing relationships sampled from overseas Chinese firms. The results generally support the authors' framework; however, the mediating hypotheses are not supported. There is evidence of systematic differences in the effects of the studied antecedents on commitment and trust. Furthermore, a multigroup analysis provides evidence of significant moderating effects due to contracting mode. The study provides new insights into the theory and practice of industrial marketing. (C) 2003 Elsevier Science Inc. All rights reserved.
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We assayed mtDNA haplotype [300 base pairs (bp) control region] geography and genealogy in the Indo-Pacific tasselfish, Polynemus sheridani from its contiguous estuarine distribution across northern Australia (n = 169). Eight estuaries were sampled from three oceanographic regions (Timor Sea, Gulf of Carpentaria and the Coral Sea) to assess the impact of Pleistocene sea level changes on the historical connectivity among P. sheridani populations. Specifically, we investigated the genetic consequences of disruption to Indian-Pacific Ocean connectivity brought about by the closure of the Torres Strait. Overall there was significant population subdivision among estuaries (F-ST = 0.161, (Phi(ST) = 0.187). Despite a linear distribution, P. sheridani did not show isolation by distance over the entire sampled range because of genetic similarity of estuaries greater than 3000 km apart. However, significant isolation by distance was detected between estuaries separated by less than 3000 km of coastline. Unlike many genetic studies of Indo-Pacific marine species, there was no evidence for an historical division between eastern and western populations. Instead, phylogeographical patterns were dominated by a starlike intraspecific phylogeny coupled with evidence for population expansion in both the Gulf of Carpentaria and the Coral Sea but not the Timor Sea. This was interpreted as evidence for recent west to east recolonization across of northern Australia following the last postglacial marine advance. We argue that although sufficient time has elapsed postcolonization for populations to approach gene flow-drift equilibrium over smaller spatial scales (< 3000 km), the signal of historical colonization persists to obscure the expected equilibrium pattern of isolation by distance over large spatial scales (> 3000 km).
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Modeling physiological processes using tracer kinetic methods requires knowledge of the time course of the tracer concentration in blood supplying the organ. For liver studies, however, inaccessibility of the portal vein makes direct measurement of the hepatic dual-input function impossible in humans. We want to develop a method to predict the portal venous time-activity curve from measurements of an arterial time-activity curve. An impulse-response function based on a continuous distribution of washout constants is developed and validated for the gut. Experiments with simultaneous blood sampling in aorta and portal vein were made in 13 anesthetized pigs following inhalation of intravascular [O-15] CO or injections of diffusible 3-O[ C-11] methylglucose (MG). The parameters of the impulse-response function have a physiological interpretation in terms of the distribution of washout constants and are mathematically equivalent to the mean transit time ( T) and standard deviation of transit times. The results include estimates of mean transit times from the aorta to the portal vein in pigs: (T) over bar = 0.35 +/- 0.05 min for CO and 1.7 +/- 0.1 min for MG. The prediction of the portal venous time-activity curve benefits from constraining the regression fits by parameters estimated independently. This is strong evidence for the physiological relevance of the impulse-response function, which includes asymptotically, and thereby justifies kinetically, a useful and simple power law. Similarity between our parameter estimates in pigs and parameter estimates in normal humans suggests that the proposed model can be adapted for use in humans.
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The parasite fauna of Spanish mackerel Scomberomorus commerson from 10 sites across northern Australia and one site in Indonesia, was examined to evaluate the degree of movement and subsequent stock structure of the fish. Kupang fish (Indonesia) had very few Terranova spp.. Grillotia branchi, Otobothrium cysticum or Pterobothrium sp. compared to Australian fish, indicating that no Australian fish enter the Kupang fishery. Univariate and discriminant function analysis of four 'temporary' parasite species, the copepod Pseudocyenoides armatus and the monogeneans Gotocotyla bivaginalis, Pricea multae and Pseudothoracocotyla ovalis, demonstrated little similarity between areas of northern Australia, indicating minimal short-term exchange between neighbouring groups of S. commerson. Analyses of five 'permanent' parasite species, the larval helminths G. branchi, O. cysticum, Pterobothrium sp., Callitetrarhynchus gracilis and Paranybelinia balli, also revealed large differences between areas thus indicating long-term separation. There are at least six parasitological stocks across northern Australia: Fog Bay/Bathurst Island, Cape Wessel. Groote/Sir Edward Pellew. Mornington Island, Weipa. and the Torres Strait. The occurrence of a few irregular fish in the samples suggested that LIP to 5% of fish moved between stocks during their lifetime. The similarity of within-school variability to that between schools showed that the fish do not form long-term school associations. (C) 2003 The Fisheries Society of the British Isles.
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Anthracnose and crown rot, caused by Colletotrichum trifolii, are serious diseases of lucerne (Medicago saliva L.) in humid regions of the world. A race survey was conducted by inoculating individual lucerne clones (genotypes) with C. trifolii isolates collected from a range of Medicago hosts, locations, and years in south-eastern Queensland. This survey revealed for the first time in Australia the presence of race 2 (virulence on anthracnose resistance gene An I) and the first world report of race 4 (virulence on An(2)). A collection of North American race I and race 2 C. trifolii isolates, when inoculated onto the Australian differential clones, gave responses that were in agreement with their North American reactions. A RAPD analysis was conducted on 9 Australian C. trifolii isolates including races 1, 2, and 4; two C. destructivum and one C. gloeosporioides isolate were included as known outliers. For the C. trifolii isolates, 94.6% similarity was found regardless of host origin or race, compared with 2.2% similarity between this group and the C. gloeosporioides and C. destructivum isolates, confirming that the new races belong to C. trifolii. Currently, it is hypothesised that only plants carrying genes An, and An2 are resistant to the 3 races. Of 22 cultivars screened against the 3 races, only UQL-1, Hallmark, and Pioneer 54Q53 had >30% of plants resistant to the 3 races in separate screenings. The research highlights the need to find new sources of resistance to C. trifolii in lucerne.
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Multiple HLA class I alleles can bind peptides with common sequence motifs due to structural similarities in the peptide binding cleft, and these groups of alleles have been classified into supertypes. Nine major HLA supertypes have been proposed, including an A24 supertype that includes A*2301, A*2402, and A*3001. Evidence for this A24 supertype is limited to HLA sequence homology and/or similarity in peptide binding motifs for the alleles. To investigate the immunological relevance of this proposed supertype, we have examined two viral epitopes (from EBV and CMV) initially defined as HLA-A*2301-binding peptides. The data clearly demonstrate that each peptide could be recognized by CTL clones in the context of A*2301 or A*2402; thus validating the inclusion of these three alleles within an A24 supertype. Furthermore, CTL responses to the EBV epitope were detectable in both A*2301(+) and A*2402(+) individuals who had been previously exposed to this virus. These data substantiate the biological relevance of the A24 supertype, and the identification of viral epitopes with the capacity to bind promiscuously across this supertype could aid efforts to develop CTL-based vaccines or immunotherapy. The degeneracy in HLA restriction displayed by some T cells in this study also suggests that the dogma of self-MHC restriction needs some refinement to accommodate foreign peptide recognition in the context of multiple supertype alleles.
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The novel mammalian gene Crim1 encodes a transmembrane bound protein with similarity to the secreted bone morphogenetic protein (BMP) antagonists, vertebrate Chordin, and its Drosophila homologue short gastrulation. Crim1 is expressed in the neural tube in mouse in a restricted pattern, but its function in central nervous system development is largely unknown. We isolated the chicken Crim1 orthologue and analyzed its expression in the developing neural tube. Chicken CRIM1 shares strong homology to human/mouse CRIM1 and C. elegans CRIM1-like proteins. Crim1 is expressed in a similar but not identical pattern to that in the developing spinal cord of mouse, including the notochord, floor plate, motor neurons, and the roof plate. Unlike follistatin, a secreted inhibitor of BMPs, in ovo electroporation of CRIM1, as a full-length transmembrane bound or secreted ectodomain was not sufficient to disrupt early patterning of the neural tube. However, ectodomain CRIM1 overexpression leads to an approximate 50% decrease in populations of specific ventral neuronal populations, including ISL-1(+) motor neurons, CHX-10(+) V1, and EN-1(+) V2 interneurons.
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Women have lower iron stores than men because of iron loss during their reproductive years. However, variation between women could result from differences in iron loss, aspects of iron homeostasis common to men and women, or a combination of both. We compared the effects of age, menopause, menstrual blood loss and the number of pregnancies (sex-specific factors), and the effects of genetic variation, on markers of iron stores. We assessed how much the same genes or other familial factors influence iron status in both men and women. Data from 2039 female twins who participated in studies of reproductive health and iron status were used to estimate the proportions of variation that could be ascribed to genes, environment and measured factors. Significant effects of age, menopausal status and magnitude of menstrual blood loss were demonstrated, accounting for up to 18% of variance in serum ferritin in this sample, but number of children had no significant effect. Genetic effects were more than twice as great as sex-specific effects. The within-pair similarity of ferritin values in dizygotic female twin pairs was greater than for dizygotic opposite-sex pairs, but this difference was not quite significant, consistent with a minor role for sex-specific factors; and the opposite-sex within-pair differences did not diminish significantly with age. We conclude that the contribution of genetic differences between women to variation in iron stores outweighs the comparatively small effects of interindividual variation in iron loss through variation in menstruation and number of pregnancies.
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The pathogenesis-related (PR) protein superfamily is widely distributed in the animal, plant, and fungal kingdoms and is implicated in human brain tumor growth and plant pathogenesis. The precise biological activity of PR proteins, however, has remained elusive. Here we report the characterization, cloning and structural homology modeling of Tex31 from the venom duct of Conus textile. Tex31 was isolated to >95% purity by activity-guided fractionation using a para-nitroanilide substrate based on the putative cleavage site residues found in the propeptide precursor of conotoxin TxVIA. Tex31 requires four residues including a leucine N-terminal of the cleavage site for efficient substrate processing. The sequence of Tex31 was determined using two degenerate PCR primers designed from N-terminal and tryptic digest Edman sequences. A BLAST search revealed that Tex31 was a member of the PR protein superfamily and most closely related to the CRISP family of mammalian proteins that have a cysteine-rich C-terminal tail. A homology model constructed from two PR proteins revealed that the likely catalytic residues in Tex31 fall within a structurally conserved domain found in PR proteins. Thus, it is possible that other PR proteins may also be substrate-specific proteases.
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Atualmente, tem-se difundido a aplicação de inoculante no sulco de semeadura na cultura da soja, mas há poucas informações que dão suporte a essa prática e comprovam sua eficiência em diferentes ambientes manejados sob plantio direto. Este trabalho teve como objetivo avaliar a viabilidade da aplicação de inoculantes na cultura da soja, via semente e sulco de semeadura, em solo já cultivado ou não com soja. Foram realizados dois experimentos em campo a partir de dezembro de 2004 em Latossolo Vermelho-Amarelo, seguindo o mesmo método e tratamentos, porém em dois locais distintos, com ou sem cultivo anterior de soja. Foram testados oito tratamentos: (1) inoculação via semente (inoculante + fungicida + micronutriente); (2) sem inoculação (fungicida + micronutriente); (3) testemunha (semente pura, sem tratamento); (4) aplicação no sulco-dose 1 (dose do inoculante recomendada no sulco); (5) aplicação no sulco-dose 2 (duas vezes a dose recomendada no sulco); (6) aplicação no sulco-dose 3 (três vezes a dose recomendada no sulco); (7) sulco-dose 1 + inoculação via semente; e (8) adubação com N (200 kg ha-1 N). Foram avaliados massa de matéria seca de nódulos e número de nódulos totais e nódulos viáveis e não-viáveis aos 30 e 75 dias após emergência. A melhor nodulação foi obtida com aplicação de inoculante + fungicida + micronutriente via semente no solo ainda não cultivado. No solo previamente cultivado com soja, destacaram-se os tratamentos uma e duas vezes a dose do inoculante no sulco. Menores valores de massa seca de nódulos na soja foram obtidos no tratamento com adubação mineral. A aplicação via sulco do inoculante mostrou-se uma prática viável, em razão da semelhança dos resultados obtidos com a aplicação tradicional via semente.
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Entre março de 2011 e dezembro de 2012 foram realizadas 30 saídas de campo para avaliar os padrões de uso de habitat e estrutura de grupo de Sotalia guianensis na região da foz do rio Doce, costa norte do Espírito Santo. A coleta de dados foi realizada com auxílio de uma embarcação a partir de rotas pré-determinadas distribuídas homogeneamente na área de estudo. Informações sobre as variáveis ambientais foram coletadas a cada hora de amostragem e a cada grupo de golfinhos avistado. Através da análise de Cluster foram identificados três diferentes habitats baseados na similaridade entre variáveis ambientais. Durante 242hs48min de amostragem foram percorridos 1.523km e 119 grupos de botos-cinza foram avistados. Grupos de Sotalia guianensis, assim como indivíduos imaturos, foram observados ao longo de todo o ano na área de estudo, não apresentando diferença sazonal entre as estações seca (abril a setembro) e chuvosa (outubro a março). Os grupos apresentaram uma média de 9,9 indivíduos. Animais imaturos estavam presentes na maioria dos grupos (71%), apresentando uma relação direta com o número de adultos. Os botos-cinza apresentaram o uso quase exclusivo da região marinha aberta adjacente à desembocadura do rio apontando um padrão de uso de habitats heterogêneo, onde as áreas de maior concentração de golfinhos não corresponderam às áreas preferenciais de alimentação. Os resultados obtidos neste trabalho refletem como S. guianensis responde a complexidade dos fatores bióticos e abióticos da área de estudo, apontando um padrão de uso de habitat diferenciado para a espécie.
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O maracujazeiro pertence à família Passifloraceae e ao gênero Passiflora que é o mais importante economicamente. Altitudes entre 100 a 900 m são indicadas para o plantio do maracujazeiro e estudos sobre localizações geográficas distintas possibilitam expressões do genótipo, influenciadas pelas condições ambientais. O gradiente altitudinal influencia a distribuição da variação genética dentro e entre populações de plantas e a diversidade genética muda com a altitude. O presente trabalho teve como objetivo avaliar a qualidade fisiológica de sementes e a diversidade genética de maracujazeiros cultivados em diferentes altitudes do Espírito Santo. Para avaliação da qualidade fisiológica das sementes, os frutos de Passiflora spp. maduros foram colhidos em pomares localizados em altitudes baixa (0-100 m), média (>100 até 600 m) e alta (>600 m) de diferentes municípios do Espírito Santo. Os tratamentos pré-germinativos nas sementes foram: T1- escarificação física, feita manualmente com lixa d´água nº 120; T2- tratamento com ácido giberélico (GA3) na concentração de 500 mg L-1 com embebição por 24 horas e T3- sementes sem escarificação realizados nas sementes em laboratório e em casa de vegetação. Foi avaliado o envelhecimento acelerado tradicional, envelhecimento acelerado com saturação salina e deterioração controlada em sementes de maracujá amarelo sem escarificação localizado em alta altitude e as condições que apresentaram menor deterioração das sementes para aplicação às demais espécies e altitudes com os respectivos tratamentos pré-germinativos que apresentaram maiores valores de germinação e vigor em laboratório e em casa de vegetação. Assim, para as sementes do maracujá amarelo utilizou-se o tratamento sem escarificação, para sementes de maracujá roxo, a escarificação física e para as sementes de maracujá doce, o tratamento com ácido giberélico. O teste de envelhecimento acelerado com saturação salina a 43 ºC por 72 horas e deterioração controlada a 25% de umidade expostas por 24 horas diferencia as espécies nas diferentes altitudes. Sementes de maracujá amarelo e sementes localizadas em alta altitude apresentam qualidade fisiológica superior. Para a avaliação da diversidade genética foram utilizadas folhas jovens de cinco plantas matrizes de Passiflora edulis Sims f. flavicarpa Degener, P. edulis Sims e P. alata Curtis cultivadas em três altitudes (baixa, média e alta) do Espírito Santo. Para SSR foi encontrado baixo número de alelos, alta heterozigosidade esperada e altos valores de PIC e para a análise ISSR detectou um elevado número de bandas por primer e alto polimorfismo. Há maior similaridade genética entre P. edulis f. flavicarpa Deg. e P. edulis. Passiflora alata apresenta maior distância genética em relação às espécies. As populações de baixa altitude se diferenciam das demais independente da espécie e do marcador utilizado.
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Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Ecologia, 2016.
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The objectives of this study were to identify anthophilous butterflies on psychophilous flowers of four Asteraceae species in an Atlantic Forest fragment in Viçosa, Minas Gerais State, Southeastern Brazil, and to determine whether there are species in common with other lepidopteran inventories of the Southeastern and Midwestern regions of Brazil. It is the first inventory of anthophilous butterflies of a semideciduous forest fragment in Zona da Mata, State of Minas Gerais. A total of 108 species were recorded, representing the fourth largest lepidopteran survey in this State. The results demonstrated that Asteraceae species may be important tools for monitoring anthophilous butterflies. The similarity with other inventories ranged from 1 to 92.55%. Fifteen species were reported for the first time in the State of Minas Gerais, and among them, Melanis alena and Thisbe irenea were observed in this study only.
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In this paper we present a method for real-time detection and tracking of people in video captured by a depth camera. For each object to be assessed, an ordered sequence of values that represents the distances between its center of mass to the boundary points is calculated. The recognition is based on the analysis of the total distance value between the above sequence and some pre-defined human poses, after apply the Dynamic Time Warping. This similarity approach showed robust results in people detection.