732 resultados para Nun moth


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Population Structure and reproductive Maturity of females were investigated in the shrimp Artemesia longinaris Bate, 1888 from coastal waters of northern São Paulo State (Brazil. 23 degrees S) and Mar del Plata (Argentina, 38 degrees S) from June 2001 to May 2002. Monthly collections were taken by, commercial shrimp fishing boats equipped with bottom trawl nets. Population parameters from size frequency distributions and size (carapace length = CL) of female reproductive maturity were analyzed and compared front the two sampling areas. Latitudinal trends in reproductive parameters of A. longinaris were shown in overall body size and size of reproductive maturity, both of which were smaller in females from the tropical location than those front the cold-temperate sampling area. Largest females (> 30 turn CL) were collected in Argentina, while Brazilian specimens reached maximum size at 27 nun CL. The smallest Size of female sexual maturity was estimated at 13.6 nun CL in Brazilian samples compared to 22.1 mm CL calculated for those from Argentina. Populations from both regions exhibited a bimodal size distribution in the spring, with the peak at small body size probably corresponding to recent recruits and the peak at larger body, size to reproductive females or shrimps migrating in from deeper waters or other latitudinal regions. In late spring and summer. an intrusion of the cold South Atlantic Coastal Water mass was observed which lowered water temperature and stimulated plankton production. The primary food source for the larvae of a typically cold-temperate species such as A. longinaris. The trend of increasing body size and delay of sexual maturity with increasing latitude appears to be correlated with the decreasing water temperature and increasing plankton productivity at higher latitudes.

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Purpose: The aim of this study was to evaluate the possibility of obtaining guided bone regeneration using a poly-tetrafluoroethylene (PTFE) nonporous barrier for 2 endosseous implants, partially inserted in tibiae of rabbits.Materials and Methods: Histologic characteristics of the interface between titanium implants (one group with titanium plasma-coated implants and the other group with acid-treated surfaces) and of the regenerated bone were also studied. Twenty screw-vent implants were placed in tibiae of 5 male New Zealand rabbits, 2 at the right side and 2 at the left side, protruding 3 mm from the bone level, to create a horizontal bone defect. At the experimental group the implants were with a PTFE nonporous barrier, whereas no barriers were used in contralateral implants. Animals were sacrificed 3 months after surgery and biopsy specimens were evaluated histologically and histomorphometrically under light microscopy. Student's t test was used for statistical analysis.Results: The histologic measurements showed a mean gain in bone height of 2.15 and 2.42 mm for the barrier group and 1.95 and 0.43 mm for the control group, for the titanium plasma-spray and acid-treated implant surfaces, respectively.Conclusion: The results of the investigation revealed that the placement of implants protruding 3 nun from crestal bone defects may result in vertical bone augmentation using a nonporous PTFE barrier. (Implant Dent 2009;18:182-191)

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Employing the general principles of classification of SU3 states, we have found 285 quantum number isomers (QNI), i.e. nuclei for which there are two possible SU3 quantum number sets, characterized by the maximal eigenvalue of the SU3 group Casimir operator, at the minimal value N-0(min) for the quantum number N-0 of the group U3(A-1) symmetric representation, allowed by the Pauli principle. 41 of these QNI can be attributed to the nun-excited, ground SU3 configurations of realistic nuclei. Two examples of QNI: Si-28 and Zn-60, have been studied in detail in the framework of the strictly restricted dynamics model (SRDM).

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

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Os ácaros fitoseídeos, especialmente Neoseiulus californicus (McGregor), são importantes agentes de controle biológico de ácaros tetraniquídeos-praga nas culturas de pomáceas no Alto Valle del Río Negro y Neuquén, Argentina. Neste trabalho, avaliou-se a mortalidade de N. californicus quando exposto a resíduos dos inseticidas azimphos-methyl, carbaryl e cyfluthrin, e dos acaricidas cyhexatin e propargite. Os produtos foram aplicados às concentrações recomendadas em plantas de pereira. Um, três, seis e dez dias após a aplicação (DAA), folhas tratadas foram retiradas das plantas para a preparação de unidades experimentais. Cinco adultos de N. californicus, provenientes de criação-estoque, foram transferidos para cada unidade, onde pólen de taboa foi fornecido como alimento. As unidades foram mantidas a 25 ± 2 ºC, 60 ± 10% de umidade relativa e fotoperíodo de 14 h. A mortalidade do ácaro foi avaliada 24 h após o confinamento. As médias de mortalidade foram comparadas pelo teste de Dunnett, a 5% de probabilidade. A progressão do declínio do efeito dos produtos testados foi submetida à análise de regressão. Nas duas primeiras datas de avaliação, todos os produtos apresentaram valores de mortalidade significativamente diferentes da testemunha tratada com água. Seis dias após a aplicação, propargite, cyhexatin e cyfluthrin apresentaram mortalidade de aproximadamente 30%, enquanto a mortalidade nos tratamentos azimphos-methyl e carbaryl apresentou níveis estatisticamente similares aos da testemunha. Dez dias após a aplicação, a mortalidade em todos os tratamentos não diferiu significativamente da testemunha. O efeito de todos os produtos apresentou declínio progressivo ao longo do período de observação, sendo significativa a 1% de probabilidade a regressão linear negativa para os valores obtidos. Os maiores efeitos negativos sobre a sobrevivência de N. californicus corresponderam aos acaricidas testados. Azimphos-methyl foi o produto que menos afetou a sobrevivência do ácaro predador. Os inseticidas testados, usados na região do Alto Valle del Río Negro y Neuquén para o controle de Cydia pomonella, praga-chave das culturas de pomáceas, apresentaram baixa toxicidade sobre N. californicus.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Os autores apresentam e discutem aspectos dos acidentes causados por larvas de lepidópteros (mariposas), enfatizando as manifestações dermatológicas e a dor intensa que caracterizam estes agravos. Além disso, são apresentadas larvas de mariposas que causam manifestações extracutâneas, tais como severos distúrbios de coagulação e artropatias anquilosantes, e ainda dermatites provocadas por insetos adultos. Os principais grupos de lepidópteros causadores de acidentes em humanos são demonstrados, e as medidas terapêuticas atualizadas são discutidas. O lepidopterismo e o erucismo são acidentes comuns, e é importante que o dermatologista saiba reconhecer e tratar esse tipo de envenenamento.

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Statement of problem. The success of metal-ceramic restorations is influenced by the compatibility between base metal alloys and porcelains. Although porcelain manufacturers recommend their own metal systems as the most compatible for fabricating metal-ceramic prostheses, a number of alloys have been used.Purpose. This study evaluated the shear bond strength between a porcelain system and 4 alternative alloys.Material and methods. Two Ni-Cr alloys: 4 ALL and Wiron 99, and 2 Co-Cr alloys: IPS d.SIGN 20 and Argeloy NP were selected for this study. The porcelain (IPS d.Sign porcelain system) portion of the cylindrical inetal-ceramic specimens was 4 mm thick and 4 mm high; the metal portion was machined to 4 x 4 mm, with a base that was 5 nun thick and 1 mm high. Forty-four specimens were prepared (n=11). Ten specimens from each group were subjected to a shear load oil a universal testing machine using a 1 min/min crosshead speed. One specimen from each group was observed with a scanning electron microscope. Stress at failure (MPa) was determined. The data were analyzed with a 1-way analysis of variance (alpha=.05).Results. The groups, all including IPS d.Sign porcelain, presented the following mean bond strengths (+/-SD) in MPa: 4 ALL, 54.0 +/- 20.0; Wiron, 63.0 +/- 13.5; IPS d.SIGN 20, 71.7 +/- 19.2; Argeloy NP, 55.2 +/- 13.5. No significant differences were found among the shear bond strength values for the metal-ceramic specimens tested.Conclusion. None of the base metal alloys studied demonstrated superior bond strength to the porcelain tested.

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HDPE and PVC geomembranes are sensitive to changes in their properties when in contact with high temperatures. The effects of hot temperature on polymeric geomembranes are assessed by the ASTM D794 and ASTM D5721.This paper brings an analysis of degradation of the Poly Vinyl Chloride (PVC) and High Density Poly Ethylene (HDPE) geomembranes when exposed to conventional and air oven after specific periods.. Mechanical and physical properties were evaluated. OIT tests were also performanced to evaluate the level of oxidation degradation occurred on the HDPE geomembranes. Geomembranes of two thicknesses were tested: 1.0, 2.0 nun (PVC) and 0.8, 2.5 mm, (HDPE). The results obtained show, for example, that after the last period of exposure, the PVC geomembranes (1.0, 2.0 mm) were more rigid and stiffer than fresh samples. The HDPE geomembranes, on the other hand, when exposed to heat presented increases in deformation. OIT tests showed efficient to detect some level of degradation on the HDPE geomembranes.

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SrBi2Ta2O9 thin films, produced by the polymeric precursor method, were crystallized at low temperature using a domestic microwave oven. A SiC susceptor were used to absorb the microwave energy and rapidly transfer the heat to the film. Low microwave power and short time have been used. The films thus obtained are crack-free, well-adhered, and fully crystallized, even when treated at 600 degreesC for 10 min. The microstructure displayed a polycrystalline nature with an elongate grain size comparable to the films obtained by the conventional treatment. The dielectric constant values are 240, 159 and 67, for the films treated at 600 degreesC, 650 degreesC and 700 degreesC, respectively, when the films are placed directly on the SiC susceptor. Electrical measurements revealed that the increase of the temperature treatment to 700 degreesC causes a complete loss of ferroelectricity due to degradation of the bottom interface. A 4 nun-ceramic wool put between the susceptor and the substrate minimizes the interface degradation leading to a dielectric constant, a dielectric loss, and a remnant polarization (2P(r)) of 181 muC/cm(2), 0.032 muC/cm(2), and 12.8 muC/cm(2), respectively, for a film treated at 750 degreesC for 20 min. (C) 2004 Elsevier B.V. All rights reserved.

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Purpose : the aim of this study was to evaluate the effect of nozzle angle and tip diameter on the cutting efficiency of an air abrasion system. Materials and Methods: Thirty-six extracted human third molars were air-abraded with the PrepStar microabrasion machine using a handpiece with either 80degrees or 45degrees nozzle angles with 0.38 or 0.48 nun tip orifice diameters. The following parameters were held constant: abrasive particle size (27 mum), air pressure (80 psi), distance (2 mm.) and duration (15 seconds). The cutting efficiency was compared using enamel, dentin and cementum substrates. Width and depth of the cutting patterns were analyzed and measured using scanning electron micrographs. Results: Statistical analysis using three-way ANOVA and Duncan's Multiple Range test revealed that the width of the cuts was significantly greater when the cavities were prepared using the 45degrees nozzle angle. Significantly deeper cavities were produced with the 80degrees nozzle angle. The tip orifice of the nozzle influenced the cutting efficiency in softer substrates, dentin and cementum. Precise removal of hard tissue is best accomplished using the 80degrees angle nozzle tips for all types of tooth surfaces, enamel, dentin and cementum.

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Purpose: This study evaluated the adhesive quality of simplified self-adhesive and conventional resin cements to Y-TZP in dry and aged conditions. Methods: Y-TZP ceramic blocks (N=192) (5 x 5 x 2 mm) were embedded in acrylic resin and randomly divided into two groups, based on surface conditioning: 96% isopropanol or chairside tribochemical silica coating and silanization. Conditioned ceramics were divided into four groups to receive the resin cements (Panavia F 2.0, Variolink II, RelyX U100 and Maxcem). After 24 hours, half of the specimens (n=12) from each group were submitted to shear bond strength testing (0.5 nun/minute). The remaining specimens were tested after 90 days of water storage at 37 degrees C and thermocycling (12,000x, 5 degrees C-55 degrees C). Failure types were then assessed. The data were analyzed using three-way ANOVA and the Tukey's test (alpha=0.05). Results: Significant effects of ceramic conditioning, cement type and storage conditions were observed (p<0.0001). The groups cleaned using alcohol only showed low bond strength values in dry conditions and the bond strength was reduced dramatically after aging. Groups conditioned using silica coating and silanization showed higher bond strengths both in dry and aged conditions. A high number of specimens failed prematurely prior to testing when they were cleaned using 96% isopropanol. Conclusion: Overall, silica coating and silanization showed higher, stable bond strengths with and without aging. The durability of resin-ceramic adhesion varied, depending on the adhesive cement type.