997 resultados para 37:659.3


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A modelagem baseada no indivíduo tem sido crescentemente empregada para analisar processos ecológicos, desenvolver e avaliar teorias, bem como para fins de manejo da vida silvestre e conservação. Os modelos baseados no indivíduo (MBI) são bastante flexíveis, permitem o uso detalhado de parâmetros com maior significado biológico, sendo portanto mais realistas do que modelos populacionais clássicos, mais presos dentro de um rígido formalismo matemático. O presente artigo apresenta e discute sete razões para a adoção dos MBI em estudos de simulação na Ecologia: (1) a inerente complexidade de sistemas ecológicos, impassíveis de uma análise matemática formal; (2) processos populacionais são fenômenos emergentes, resultando das interações entre seus elementos constituintes (indivíduos) e destes com o meio; (3) poder de predição; (4) a adoção definitiva, por parte da Ecologia, de uma visão evolutiva; (5) indivíduos são entidades discretas; (6) interações são localizadas no espaço e (7) indivíduos diferem entre si.

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Felids play an important role in structuring the prey community, and thus in the dynamics of the plant community in tropical forests. The diets of three species of small cats, Leopardus pardalis (ocelot), L. wiedii (margay), and L. tigrinus (oncilla) were investigated by analysis of scats and regurgitations during a one-year study at Parque Estadual Serra do Mar, Nucleo Santa Virginia, southeastern Brazil. Small non-volant mammals were the most frequent prey in all the diets. The diets of the three cats were similar but although they consumed the same prey items, they showed differential use of them. Ocelots consumed more reptiles than the other species, oncillas preyed on birds and arboreal marsupials, whereas margays were generalists.

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This paper reports the novel application of digital curvature as a feature for morphological characterization and classification of landmark shapes. By inheriting several unique features of the continuous curvature, the digital curvature provides invariance to translations, rotations, local shape deformations, and is easily made tolerant to scaling. In addition, the bending energy, a global shape feature, can be directly estimated from the curvature values. The application of these features to analyse patterns of cranial morphological geographic differentiation in the rodent species Thrichomys apereoides has led to encouraging results, indicating a close correspondence between the geographical and morphological distributions. (C) 2003 Pattern Recognition Society. Published by Elsevier Ltd. All rights reserved.

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A nuclear or leader species is the one around which foraging activity is organized. In the campo-cerrado (Brazilian savannah) up to four bird species (Saltator atricollis, Cypsnagra hirundinacea, Mimus saturninus, and Neothraupis fasciata) may function as nuclear or leader species in mixed species flocks. The aim of this study was to assess the features shown by these nuclear species. I quantified parameters of sociality, communication and alertness of nuclear bird species in mixed flocks with different composition. Parameters related to sociality (mean intraspecific group size) and communication (frequency of contact calls) were not correlated with the leadership. on the other hand, the most alert species was in the front of a given mixed flock most of the time. The leader species spent more time in vigilance and gave most alarm calls due to approaching raptors earlier. The results of this study strongly suggest that the alertness of a species is the major character of nuclear bird species in mixed flocks of the campo-cerrado.

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

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Macroalgas são organismos tipicamente bentônicos, constituídos por um talo maduro, discreto e reconhecível a olho nu, cuja identificação microscópica é necessária. Diversos estudos foram realizados visando o conhecimento taxonômico em riachos brasileiros, no entanto, são raros os trabalhos que abordam as algas que se desenvolvem nas nascentes destes riachos. de fevereiro a setembro/2007 coletas mensais foram realizadas em nascentes e em suas imediações (solos úmidos dos afloramentos d'água) de quatro riachos na região noroeste do estado de São Paulo. O levantamento taxonômico resultou na identificação de 13 espécies, sendo 54% dos táxons pertencentes a Cyanophyta e 46% a Chlorophyta. Cylindrospermum gorakhpurense, Mougeotia gotlandica, Spirogyra gallica e S. taftiana são registradas pela primeira vez para o Brasil. A flora aquática encontrada diferiu da regional devido à presença de organismos da família Zygnemataceae (Chlorophyta) em estágio reprodutivo. Este tipo de hábitat mostrou-se especialmente favorável à reprodução das Zygnemataceae.

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Several spider species use plants as shelter and foraging sites, but the relationships among these organisms are still poorly known. Lynx spiders of the genus Peucetia do not build webs, and many species live strictly in plants bearing glandular trichomes. Peucetia flava Keyserling 1877 inhabits Solanum thomasifolium in southeastern Brazil and usually preys on herbivores and other small insects adhered to the glandular trichomes of its host plant. To evaluate the potential anti-herbivore protection. of this spider species for S. thomasifolium, we glued termites used as herbivore models oil trichomes of S. thomasifolium and on neighboring plants lacking glandular trichomes. leaf miner damage and spider density were recorded for S. thomasifolium plants in July 1997. There was a positive relationship between plant size and spider density. The removal or termites in S. thomasifolium by P. flava was higher than ill plants without glandular trichomes. The leaf miner damage was negatively related to spider density. Our results Suggest that P. flava may be all important plant bodyguard in the defense of S. thomasifolium from its natural herbivores.

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Statement of problem. According to manufacturers, bonding with self-adhesive resin cements can be achieved without any pretreatment steps such as etching, priming, or bonding. However, the benefit of saving time with these simplified luting systems may be realized at the expense of compromising the bonding capacity.Purpose. The purpose of this study was to assess whether different dentin conditioning protocols influence the bond performance of self-adhesive resin cements to dentin.Material and methods. Flat dentin surfaces from 48 human molars were divided into 4 groups (n=12): 1) control, no conditioning; 2) H(3)PO(4), etching with 37% H(3)PO(4) for 15 seconds; 3) SEBond, bonding with self-etching primer adhesive (Clearfil SE Bond); and 4) EDTA, etching with 0.1M EDTA for 60 seconds. The specimens from each dentin pre-treatment were bonded using the self-adhesive cements RelyX Unicem, Maxcem or Multilink Sprint (n=4). The resin-cement-dentin specimens were stored in water at 37 degrees C for 7 days, and serially sectioned to produce beam specimens of 1.0 mm(2) cross-sectional area. Microtensile bond strength (mu TBS) testing was performed at 1.0 mm/min. Data (MPa) were analyzed by 2-way ANOVA and Tukey multiple comparisons test (alpha=.05). Fractured specimens were examined with a stereomicroscope (x40) and classified as adhesive, mixed, or cohesive. Additional bonded interfaces were evaluated under a scanning electron microscope (SEM).Results. Cement-dentin mu TBS was affected by the dentin conditioning approach (P <.001). RelyX Unicem attained statistically similar bond strengths to all pre-treated dentin surfaces. H(3)PO(4)-etching prior to the application of Maxcem resulted in bond strength values that were significantly higher than the other groups. The lowest mu TBS were attained when luting Multilink Sprint per manufacturers' recommendations, while H(3)PO(4)-etching produced the highest values followed by Clearfil SE bonding and EDTA. SEM observations disclosed an enhanced potential of the self-adhesive cements to form a hybrid layer when applied following manufacturer's instructions.Conclusions. When evaluated self-adhesive resin cements are used, selectively etching dentin with H(3)PO(4) prior to luting results in the most effective bonding. (J Prosthet Dent 2011;105:227-235)

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We investigate dynamical effects of a bright soliton in Bose-Einstein condensed (BEC) systems with local and smooth space variations of the two-body atomic scattering length. It includes a discussion about the possible observation of a new type of standing nonlinear atomic matter wave in cigar-type traps. A rich dynamics is observed in the interaction between the soliton and an inhomogeneity. By considering an analytical time-dependent variational approach and also full numerical simulation of one-dimensional and three-dimensional Gross-Pitaevskii equations, we study processes such as trapping, reflection and transmission of the bright matter soliton due to the impurity. We also derive conditions for the collapse of the bright solitary wave, considering a quasi-one-dimensional BEC with attractive local inhomogeneity.

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Intestinal obstruction occurs in chelonian mainly due parasitism and foreign bodies, as stones and sand. An intestinal compaction was described in a five year-old male d'orbigny's slider which was taken to the Veterinary Medical Teaching Hospital of the UNICASTELO, at Fernandopolis, SP, Brazil, presenting anorexia for a week, severe dehydration and stupor. Definitive diagnostic was performed by radiographic exam and great amount of intestinal radiopac substance was detected. The animal went through emergency celiotomy for removing the intestinal foreign bodies. Inhalatory anesthesia with isofluorane was used for anesthesia induction and manutention. After local antisepsy, a 4cm(2) oblique opening was conducted on plastron by using a vibratory saw. Peritoneum was cut, intestines exteriorized and enterotomy performed. During the surgery, the animal was radiographed to confirm the complete taken out of the foreign bodies. Mononylon 4-0 strand was applied for intestinal suture in two planes. The plastron piece that was taken out was replaced and set with epoxy resine and gaze on the surgical window, making it waterproof. In the postoperative time, animal was medicated with analgesics for two days and pentabiotics for five days. Oral creamy diet was used with oral tube from the second to tenth day, what provided a great clinicosurgical recovering.

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

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Iphiseiodes zuluagai Denmark & Muma é um importante predador de Brevipalpus phoenicis (Geijskes) em citros no Brasil. O emprego de Tyrophagus putrescentiae (Schrank) como fonte de alimento para I. zuluagai em criações de laboratório foi investigado a 25,5 ± 0,5ºC, 88 ± 7% UR e fotofase de 12h. Inicialmente os níveis de oviposição do predador alimentado com ovos, estágios pós-embrionários mortos ou estágios pós-embrionários vivos de T. putrescentiae foram avaliados durante 10 dias. A taxa diária de oviposição foi de 1,3 ovo/ fêmea quando estas foram alimentadas com ovos de T. putrecentiae; 0,7 ovo/ fêmea quando estas foram alimentadas com estágios pós-embrionários mortos e cerca de 0,2 ovo/ fêmea quando alimentadas com estágios pós-embrionários vivos. Posteriormente, elaborou-se a tabela de vida de I. zuluagai, oferecendo-se como alimento ovos de T. putrescentiae. Os estágios imaturos foram observados a cada 8h, para determinar a duração correspondente. Na fase adulta, os ácaros foram observados a cada 24h, para se determinar os parâmetros reprodutivos. A capacidade de aumento populacional (r m) foi de 0,11 fêmea/ fêmea/ dia; resultando em uma razão finita de aumento de 1,11 (l). A taxa líquida de reprodução (R0) foi de 7,1 fêmeas/geração, com um tempo de geração de 18,6 dias. Os resultados obtidos mostram que T. putrescentiae é uma fonte de alimento favorável ao desenvolvimento de I. zuluagai.

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Nesse trabalho, o objetivo foi avaliar a reação de oito porta-enxertos de videira aos nematoides das lesões radiculares. As estacas dos porta-enxertos Kober, SO4, 101-14, R99, 420-A, Rupestris du Lot, Riparia do Traviú e Telek 5C, cedidas pelo Centro APTA de Frutas/IAC, foram plantadas em vasos contendo mistura de solo:areia na proporção 2:1 (v:v) e mantidas em casa de vegetação. Após quatro meses, os porta-enxertos foram inoculados com 1.200 espécimes de Pratylenchus brachyurus ou P. zeae, e o milho foi usado para comprovar a viabilidade do inóculo. Aos 180 dias após a inoculação, avaliou-se o número de nematoides por sistema radicular e em 100 cm³ de solo. O milho foi avaliado aos 90 dias após a inoculação e cada vaso recebeu uma nova planta, que foi avaliada juntamente com os porta-enxertos. No milho, as populações finais de P. brachyurus e P. zeae foram respectivamente iguais a 8.040 e 6.940 indivíduos. Todos os porta-enxertos comportaram-se como imunes a P. brachyurus e P. zeae, isto é, a população final dos nematoides e o fator de reprodução foram iguais a zero. Recuperaram-se seis e 11 espécimes de P. zeae nas amostras de solo cultivadas com os porta-enxertos Kober e 420-A, respectivamente. Conclui-se que os porta-enxertos estudados apresentam potencial para serem usados em áreas infestadas com esses nematoides das lesões.