23 resultados para 1st Principles

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


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Morphological structures of the head of 1st and 5th instar nymphs of Triatoma circummaculata and Triatoma rubrovaria were revealed by analysis using scanning electron microscopy (SEM). Differences between Ist and 5th instar nymphs of these two species were observed in the postocular callosity, the number of ommatidia and tapered hair, the small segment between antennal segments, the rostrum third segment and slit lines. These slit lines were different only in the 5th instar. Similarities observed were the presence of tapered hairs in the joints, and the type of sensilla in the antennal segments. Only the Ist instar shows anteclypeus and gena sensilla. The antennal segments comprise the following types of sensilla: basiconica, bristles type I, bristles type II, bristles type III, campaniformia, coeloconica, chemosensilla, placodea, trichobothria and trichoidea. We describe here for the first time six (3+3) sensilla basiconica on the dorsal portion of the first segment of the rostrum. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

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Visible photoluminescence (PL) was observed for the first time at room temperature in structurally disordered calcium strontium tungstate powder, Ca0.60Sr0.40WO4 (CSW), obtained by the polymeric precursor method. The PL behavior of CSW powders has been analyzed as a function of the disorder rate, based on experimental and theoretical studies. Quantum mechanical theory based on density functional theory at the B3LYP level has been employed to study the electronic structure of two periodic models representing both crystalline and disordered powders. Their electronic structures have been analyzed in terms of density of states, band dispersion and charge densities. The calculations indicate a break in symmetry when passing from crystalline to disordered models, creating localized electronic levels above the valence band. Moreover, a negative charge transfer process takes place from the [WO3] cluster to the [WO4] cluster. The polarization induced by the break in symmetry and the existence of localized levels favors the creation of trapped holes and electrons, originating the PL phenomenon. (c) 2007 Elsevier B.V. All rights reserved.

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Toxic principles from seeds of Aeschynomene indica collected in Brazil were analyzed. Dalpanol, 12 alpha-hydroxydalpanol and 11-hydroxydalpanol were identified using (1)H NMR in A. indica for the first time. 11-hydroxydalpanol has not been previously reported in the existing literature. Furthermore these rotenoids are likely the toxic principles that cause neurological signs in mice.

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OBJETIVO: Elaborar uma bateria de provas que se propõe a avaliar o processamento de habilidades necessárias para a aquisição do sistema de escrita alfabético do Português do Brasil, e caracterizar e comparar o desempenho dos escolares de 1ª a 4ª série do ensino fundamental nas provas desta bateria. MÉTODOS: Foram elaboradas provas específicas para este fim, seguindo os princípios fonológicos da língua portuguesa do Brasil. Foram avaliados 120 escolares de 1ª a 4ª séries, sendo 30 de cada série escolar divididos em quatro grupos, respectivamente GI, GII, GIII e GIV. As provas elaboradas e aplicadas foram: prova de habilidades metafonológicas (identificação e manipulação de sílabas e fonemas, além de repetição de não-palavras); prova de leitura (leitura de palavras reais e de pseudopalavras). RESULTADOS: Houve diferenças estatisticamente significantes entre os grupos nas habilidades metafonológicas com as médias diminuindo da 1ª à 4ª série sucessivamente. Também houve diferenças quanto ao tempo de leitura de palavras reais e de pseudopalavras, com as médias diminuindo da 1ª à 3ª série, mantendo-se igual ou próximo entre esta e a 4ª série. CONCLUSÃO: Os desempenhos foram se tornando superiores da 1ª à 4ª série, sendo que os escolares obtiveram desempenhos superiores nas provas de identificação em relação às provas de manipulação, assim como os desempenhos nas provas silábicas foram superiores aos das provas fonêmicas. Há uma prevalência da rota fonológica nas séries iniciais (1ª e 2ª) com as outras séries, especialmente a 4ª, usando mais a rota lexical.

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We describe, for the first time, the predatory behaviour of Thaumatomyrmex ants on millipedes of the family Polyxenidae, based on field observations of T. atrox and a field and laboratory study of T. contumax. The capture of the prey and the removal process of its body-covering setae by the ants before they eat the millipede are described. This specialized behaviour in at least two species of the genus, belonging to two distinct groups of species, indicates a general trend in Thaumatomyrmex. We coupled this study with a comparative morphological analysis of the mouthparts and digestive tube of these and other Thaumatomyrmex species. Also, we report the first case of sympatry in the genus, which suggests that Thaumatomyrmex includes several species. and not only one highly variable taxon, as hypothesized earlier.

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Podolsky's higher-order field equations are obtained by generalizing the laws of Podolsky's electrostatics, which follow from Coulomb's generalized law and superposition, to be consistent with special relativity. In addition, it is necessary to take into account the independence of the observed charge of a particle on its speed. It is also shown that the gauge-independent term concerning the Feynman propagator for Podolsky's generalized electrodynamics has a good ultraviolet behaviour at the expense of a negative metric massive ghost which, contrary to what is currently assumed in the literature, is non-tachyonic. A brief discussion on Podolsky's characteristic length is presented as well.

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Natural predation first instar larvae of the cotton leafworm (CLW) A. argillacea was studied in cotton fields in Jaboticabal, São Paulo State, Brazil, during 1986. The presence of naturally occurring arthropod predators showed a first instar larvae predation rate of 78.6 and 88.9% after 24 h and 48 h of exposure, respectively. A predator prey ratio of 1 : 1 (1 CLW key predator per 1 prey/plant) maintained a level of no more than 1 CLW small larvae per plant. The most evident arthropod predators in the studied fields were: beetles (Coleoptera: Coccinellidae), ants Pheidole sp. and Conomyrma sp.; Dermaptera Doru lineare (Eschs); Hemiptera Geocoris sp., and Orius insidiosus Say; and the spiders Theridion volubile, Chrysso pulcherrima, Misumenops sp., Chiracanthium sp., and Oxyopes salticus Hentz.

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

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Many plants utilized in the urban center shows substances considered toxic whose production could be influenced by some factors, like hydric stress, including ornamental Nerium oleander L., widely used in gardens in various parts of the world, which presents production of cardioative glucosides, considered toxic. This study had the objective to evaluate the effect of field capacity in the biomass and the level of cardioative glucosides in seedlings of Nerium oleander. The experiment was carried at UNIDERP, in Campo Grande City, Mato Grosso do Sul State, Brazil, at the University for Development of State and Pantanal Region, using the experimental delineation in randomized blocks. There were 4 treatments (25%; 50%; 75% and 100% of the field capacity), 5 replications and 4 plants by parcel, totalling 80 plants. The evaluations were realized 60 days after the seedlings were planted. The quantitative analysis of the cardioative glucosides was realized by gravimetric test, after selective extraction of the glucosides. Were conclude that increase of the quantity of water in the soil raised the biomass production until 75% of the field capacity and increased the level of cardioative glucosides, showing that water management is very important and should be provided only the necessary to development of the plant.

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Background: Doppler ultrasonography is a non-invasive real time pulse-wave technique recently used for the transrectal study of the reproductive system hemodynamics in large animals. This technic is based in the Doppler Effect Principle that proposes the change in frequency of a wave for an observer (red blood cells) moving relative to the source of the respective wave (ultrasonic transducer). This method had showed to be effective and useful for the evaluation of the in vivo equine reproductive tract increasing the diagnostic, monitoring, and predictive capabilities of theriogenology in mares. However, an accurate and truthful ultrasonic exam requires the previous knowledge of the Doppler ultrasonography principles. Review: In recent years, the capabilities of ultrasound flow imaging have increased enormously. The current Doppler ultrasound machines offer three methods of evaluation that may be used simultaneously (triplex mode). In B-mode ultrasound, a linear array of transducers simultaneously scans a plane through the tissue that can be viewed as a two-dimensional gray-scale image on screen. This mode is primarily used to identify anatomically a structure for its posterior evaluation using colored ultrasound modes (Color or Spectral modes). Colored ultrasound images of flow, whether Color or Spectral modes, are essentially obtained from measurements of moving red cells. In Color mode, velocity information is presented as a color coded overlay on top of a B-mode image, while Pulsed Wave Doppler provides a measure of the changing velocity throughout the cardiac cycle and the distribution of velocities in the sample volume represented by a spectral graphic. Color images conception varies according to the Doppler Frequency that is the difference between the frequency of received echoes by moving blood red cells and wave frequency transmitted by the transducer. To produce an adequate spectral graphic it is important determine the position and size of the simple gate. Furthermore, blood flow velocity measurement is influence by the intersection angle between ultrasonic pulses and the direction of moving blood-red cells (Doppler angle). Objectively colored ultrasound exam may be done on large arteries of the reproductive tract, as uterine and ovary arteries, or directly on the target tissue (follicle, for example). Mesovarium and mesometrium attachment arteries also can be used for spectral evaluation of the equine reproductive system. Subjectively analysis of the ovarian and uterine vascular perfusion must be done directly on the corpus luteum, follicular wall and uterus (endometrium and myometrium associated), respectively. Power-flow imaging has greater sensitivity to weak blood flow and independent of the Doppler angle, improving the evaluation of vessels with small diameters and slow blood flow. Conclusion: Doppler ultrasonography principles, methods of evaluation and reproductive system anatomy have been described. This knowledge is essential for the competent equipment acquisition and precise collection and analysis of colored ultrasound images. Otherwise, the reporting of inconsistent and not reproducible findings may result in the discredit of Doppler technology ahead of the scientific veterinary community.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)