1,928 research outputs found
Comportamento populacional de cupiúba (Goupia glabra Aubl.) em floresta de terra firme na fazenda Rio Capim, Paragominas (PA).
Goupia glabra Aublet, popularmente conhecida como cupiúba, é uma espécie arbórea da família Celastraceae. Possui árvores de grande porte, podendo muitas vezes ocupar a posição de dossel superior em florestas primárias. É uma espécie de grande importância econômica para a região onde ocorre e para o país, sendo comercializada, inclusive, no mercado internacional, devido seus diversos usos e características peculiares. O presente estudo cruza conhecimentos de botânica, ecologia e importância comercial da espécie com informações do comportamento estrutural da cupiúba, a fim de facilitar ações de bom manejo silvicultural, inclusive juntamente com outras espécies que compõe a comunidade na área estudada e na região. Em 84 ha de floresta natural densa de terra firme, na Fazenda Rio Capim, de propriedade da Cikel Brasil Verde S. A., no município de Paragominas (PA), Goupia glabra foi uma das espécies mais representativas quanto ao seu grupo na estrutura florestal, sendo de grande importância ecológica naquela área. Considerando as árvores com diâmetro acima de 45 cm, a espécie apresenta abundância de 0,81 árvore/ha, freqüência de 100%, com área basal de 0,41 m2/ha, volume de 2,58 m3/ha, distribuição diamétrica em todas as classes de árvores, de 45 cm até 144 cm, e qualidade de fuste bem representativa para comercialização.Publicado também on-line
Capacitive micromachined ultrasonic transducers with novel membrane design
AbstractThis paper presents a novel membrane design for capacitive micromachined ultrasonic transducers (cMUTs). The proposed design is composed of a thick membrane with reinforcing beams supported by a circumferential thin membrane to improve transducer sensitivity without degrading the membrane resonance frequency. Analytical formulation of sensitivity for the proposed design was newly derived and its validity was verified by finite element analysis (FEA). From the analysis, we confirmed that this thick membrane structure achieved three times higher sensitivity compared to the conventional design by decreasing 70 % of the mass of the thick membrane part with keeping the resonance frequency same
センターリスニングがもたらすリスニング学習意欲への影響 : 大学種別・入試形態・専攻ごとの分析に基づく考察
The Center Listening Test (CLT) is a high-stakes nationwide listening test. It has been administered since 2006 in the response to the decision of the Ministry of Education, Culture, Sports, Science, and Technology (MEXT), which has been looking for its positive washback on listening learning and teaching in Japanese high schools. This research attempted to investigate to what extent the CLT has motivated students to study listening, while focusing especially on the type of their university (national or private), their majors (English-related or not), and admissions (general or recommendation). It was found that the test has exerted positive influence on students\u27 motivation to learn listening to different degrees according to the categories listed above. Several suggestions to improve the test, such as balancing the scores between the CLT and the Center written test, are made
Sequent Calculus in the Topos of Trees
Nakano's "later" modality, inspired by G\"{o}del-L\"{o}b provability logic,
has been applied in type systems and program logics to capture guarded
recursion. Birkedal et al modelled this modality via the internal logic of the
topos of trees. We show that the semantics of the propositional fragment of
this logic can be given by linear converse-well-founded intuitionistic Kripke
frames, so this logic is a marriage of the intuitionistic modal logic KM and
the intermediate logic LC. We therefore call this logic
. We give a sound and cut-free complete sequent
calculus for via a strategy that decomposes
implication into its static and irreflexive components. Our calculus provides
deterministic and terminating backward proof-search, yields decidability of the
logic and the coNP-completeness of its validity problem. Our calculus and
decision procedure can be restricted to drop linearity and hence capture KM.Comment: Extended version, with full proof details, of a paper accepted to
FoSSaCS 2015 (this version edited to fix some minor typos
Hemoglobin binding activity and hemoglobin-binding protein of Prevotella nigrescens
Prevotella nigrescens, lacking siderophores was found to bind to the hemoproteins. The binding was observed also in the envelope which was prepared by sonication of the cell. The binding occurred in the pH-dependent manner; the binding was observed below neutral pHs of the incubation mixtures but only slightly observed in the neutral and alkaline pHs. Furthermore, hemoglobin bound to the envelope was dissociated at high pHs buffers. Maximum amounts of hemoglobin bound to 1 mg envelope was 51.2 μg. Kd for the reaction at pH 5.0 was 2.1 × 10-10M (210 pM). From the dot blot assay, hemoglobin could bind to a protein solubilized from the envelope by a detergent, referred to as hemoglobin-binding protein (HbBP), then it was purified by the sequential procedures of ion exchange chromatography, affinity chromatography and isoelectric focusing. Molecular weight and isoelectric point of the HbBP were 46 kDa and 6.1, respectively
Event-related alpha suppression in response to facial motion
This article has been made available through the Brunel Open Access Publishing Fund.While biological motion refers to both face and body movements, little is known about the visual perception of facial motion. We therefore examined alpha wave suppression as a reduction in power is thought to reflect visual activity, in addition to attentional reorienting and memory processes. Nineteen neurologically healthy adults were tested on their ability to discriminate between successive facial motion captures. These animations exhibited both rigid and non-rigid facial motion, as well as speech expressions. The structural and surface appearance of these facial animations did not differ, thus participants decisions were based solely on differences in facial movements. Upright, orientation-inverted and luminance-inverted facial stimuli were compared. At occipital and parieto-occipital regions, upright facial motion evoked a transient increase in alpha which was then followed by a significant reduction. This finding is discussed in terms of neural efficiency, gating mechanisms and neural synchronization. Moreover, there was no difference in the amount of alpha suppression evoked by each facial stimulus at occipital regions, suggesting early visual processing remains unaffected by manipulation paradigms. However, upright facial motion evoked greater suppression at parieto-occipital sites, and did so in the shortest latency. Increased activity within this region may reflect higher attentional reorienting to natural facial motion but also involvement of areas associated with the visual control of body effectors. © 2014 Girges et al
Estrutura da população de maçaranduba (Manilkara huberi Standley) em 84 ha de floresta natural na Fazenda Rio Capim, Paragominas, PA.
Foi feita uma analise da estrutura da população de Manilkara huberi Standley, corn informações sobre botânica, ecologia e importância comercial da espécie. O estudo foi desenvolvido em 84 ha da Fazenda Rio Capim, propriedade da Cikel Brasil Verde Madeiras Ltda., Paragominas, PA. Foi realizado um inventario a 100% de intensidade, medindo os indivíduos com DAP ? 45 cm da espécie. Foi feita a identificação das arvores, medição do DAP e avaliação visual da qualidade de fuste. Calculou-se a abundancia, dominância, volume e distribuição diamétrica. A espécie apresentou um estoque de aproximadamente 0,7 arvore.ha-1, correspondente a 0,32 m2.ha-1 e volume de 0,72 m3.ha-1 Esta representada em todas as classes diamétricas, com maior concentração de indivíduos no intervalo diamétrico de 45 a 84 cm. Observou-se que 89% das arvores de maçaranduba possuem fustes retos, bem formados e sem defeitos; 9% apresentaram alguns defeitos, com apenas 4 m de comprimento aproveitáveis; e apenas 2% das arvores possuem fustes danificados, podres ou com inclinação maior que 45°. A espécie apresentou estoque bem distribuído nas classes de tamanho e ocorre em abundancia na área estudada.Disponível também on-line
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