996 resultados para Variable area
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Transportation Systems Center, Cambridge, Mass.
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PURPOSE: Describe a modified technique to increase nostril cross-sectional area using rib and septal cartilage graft over alar nasal cartilages. METHODS: A modified surgical technique was used to obtain, carve and insert cartilage grafts over alar nasal cartilages. This study used standardized pictures and measured 90 cadaveric nostril cross-sectional area using Autocad (c); 30 were taken before any procedure and 60 were taken after grafts over lateral crura (30 using costal cartilage and 30 using septal cartilage). Statistical analysis were assessed using a model for repeated measures and ANOVA (Analysis of Variance) for the variable "area". RESULTS: There's statistical evidence that rib cartilage graft is more effective than septal cartilage graft. The mean area after the insertion of septal cartilage graft is smaller than the mean area under rib graft treatment (no confidence interval for mean difference contains the zero value and all P-values are below the significance level of 5%). CONCLUSIONS: The technique presented is applicable to increase nostril cross section area in cadavers. This modified technique revealed to enhance more nostril cross section area with costal cartilage graft over lateral crura rather than by septal graft.
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Universidade Estadual de Campinas. Faculdade de Educação Física
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The present paper concerns on the estimative of the pressure loss and entropy variation in an isothermal fluid flow, considering real gas effects. The 1D formulation is based on the isothermal compressibility module and on the thermal expansion coefficient in order to be applicable for both gas and liquid as pure substances. It is emphasized on the simple methodology description, which establishes a relationship between the formulation adopted for ideal gas and another considering real gas effects. A computational procedure has been developed, which can be used to determine the flow properties in duct with a variable area, where real gas behavior is significant. In order to obtain quantitative results, three virial coefficients for Helium equation of state are employed to determine the percentage difference in pressure and entropy obtained from different formulations. Results are presented graphically in the form of real gas correction factors, which can be applied to perfect gas calculations.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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In constant searching for alternative biological material to perform implants and new options of experimental animal models, the objective of this investigation was to describe the mechanical properties of the peritoneum paca (Cuniculus paca Linnaeus, 1766) fresh and preserved in 98% glycerin. Samples of fresh and preserved in glycerin for periods of 30, 60 and 90 days were subjected to mechanical tests. Four adult animals, male or female, with mean body weight of eight kilograms, were used for collecting samples of the peritoneum. All tissues preserved in glycerin 98% showed a decrease in stiffness and increase in ductility and toughness. Considering the maximum force applied to the peritoneum, significant increase was observed in values (p<0.01) of samples stored for 60 and 90 days when compared to fresh material. In relation to the stretch variable, an increase was observed in all storage time of glycerin samples, verifying significant difference (p<0.01) when compared with the fresh samples. The variable area also showed significance (p <0.01) between the values of the fresh samples (5.40 mm(2)) and preserved in the glycerin by periods of 30 days (4.50 mm(2)), 60 days (9.00 mm(2)) and 90 days (7.20 mm(2)), thus indicating that the area of this membrane increased by 0.033 mm(2) per day. Generally, it was concluded that the 98% glycerin is a substance effective for the preservation of the peritoneum of the agouti paca, therefore improves its mechanical properties allowing the support membranes greater deformation forces. Thus, the results obtained in mechanical tests of the peritoneum of paca suggest its use as an alternative biological material.
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Pós-graduação em Psicologia do Desenvolvimento e Aprendizagem - FC
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We study how species richness of arthropods relates to theories concerning net primary productivity, ambient energy, water-energy dynamics and spatial environmental heterogeneity. We use two datasets of arthropod richness with similar spatial extents (Scandinavia to Mediterranean), but contrasting spatial grain (local habitat and country). Samples of ground-dwelling spiders, beetles, bugs and ants were collected from 32 paired habitats at 16 locations across Europe. Species richness of these taxonomic groups was also determined for 25 European countries based on the Fauna Europaea database. We tested effects of net primary productivity (NPP), annual mean temperature (T), annual rainfall (R) and potential evapotranspiration of the coldest month (PETmin) on species richness and turnover. Spatial environmental heterogeneity within countries was considered by including the ranges of NPP, T, R and PETmin. At the local habitat grain, relationships between species richness and environmental variables differed strongly between taxa and trophic groups. However, species turnover across locations was strongly correlated with differences in T. At the country grain, species richness was significantly correlated with environmental variables from all four theories. In particular, species richness within countries increased strongly with spatial heterogeneity in T. The importance of spatial heterogeneity in T for both species turnover across locations and for species richness within countries suggests that the temperature niche is an important determinant of arthropod diversity. We suggest that, unless climatic heterogeneity is constant across sampling units, coarse-grained studies should always account for environmental heterogeneity as a predictor of arthropod species richness, just as studies with variable area of sampling units routinely consider area.
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En este proyecto se aborda la transducción óptico-sonora utilizando métodos de tratamiento digital de imagen. Para llevar a cabo el proyecto se consideran únicamente métodos de bajo presupuesto, por lo que para realizar todo el proceso de conversión óptico-sonora se utilizan un ordenador y un escáner doméstico. Como el principal objetivo del proyecto es comprobar si es viable utilizar el tratamiento digital de imagen como conversor no se ha contemplado la utilización de equipamiento profesional. La utilidad de este proyecto está en la restauración del sonido de material fílmico con importantes degradaciones, tales que no sea posible su reproducción en un proyector. Con el prototipo que se propone, realizado con el software de programación Matlab, se consigue digitalizar el audio analógico de las películas en malas condiciones ya que la captura de audio se efectúa de manera óptica sobre las bandas sonoras. Lo conseguido en este proyecto cobra especial importancia si se tiene en cuenta la cantidad de material cinematográfico que hay en películas de celulosa. La conservación de dicho material requiere unas condiciones de almacenamiento muy específicas para que el soporte no se vea afectado, pero con el paso del tiempo es habitual que las bobinas de película presenten deformaciones o incluso ruptura. Aplicando métodos de tratamiento digital de imagen es posible restaurar el audio de fragmentos de película que no puedan ser expuestos a la tensión producida por los rodillos de los proyectores, incluso es posible recuperar el audio de fotogramas concretos ya que la digitalización del audio se realiza capturando la imagen de la forma de onda. Por ello, el procedimiento seguido para digitalizar la película debe ser poco intrusivo para garantizar la conservación del soporte fílmico. Cabe destacar que en este proyecto se ha realizado la conversión óptico-sonora sobre las bandas de sonido analógicas de área variable presentes en la película, pero el procedimiento es aplicable también a las bandas de área variable realizando modificaciones en el prototipo. Esto último queda fuera del objetivo de este proyecto, pero puede ser un trabajo futuro. ABSTRACT This project addresses optical to sound conversion using digital image processing methods. To carry out the project are considered only low-budget methods , so for all optical to sound conversion process using a computer and a home scanner . As the main application of this project is to test the feasibility of using the digital image processing as a converter does not contemplate the use of professional equipment. The main objective of this project is the restoration of sound film material with significant impairments , such is not possible playback on a projector. With the proposed prototype , made with Matlab programming software , you get digitize analog audio bad movies because the audio capture is performed optically on the soundtracks. The achievements in this project is especially important if you consider the amount of film material is in cellulose films . The preservation of such material requires a very specific storage conditions to which the support is not affected , but over time it is common for film reels presenting deformations or even rupture. Applying methods of digital image processing is possible to restore the audio from movie clips that can not be exposed to the tension produced by the rollers of the projectors , it is even possible to retrieve specific frames audio and audio that digitization is done by capturing the image of the waveform. Therefore, the procedure used to digitize the film should be bit intrusive to ensure the conservation of the film medium. Note that in this project was carried out optical to sound conversion on analog variable area soundtracks present in the film, but the procedure is applicable to variable-area bands making changes to the prototype. The latter is beyond the scope of this project, but can be a future work.
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In 2008 the regional government of Catalonia (Spain) reduced the maximum speed limit on several stretches of congested urban motorway in the Barcelona metropolitan area to 80 km/h, while in 2009 it introduced a variable speed system on other stretches of its metropolitan motorways. We use the differences-in-differences method, which enables a policy impact to be measured under specific conditions, to assess the impact of these policies on emissions of NOx and PM10. Empirical estimation indicate that reducing the speed limit to 80 km h-1 causes a 1.7 to 3.2% increase in NOx and 5.3 to 5.9% in PM10. By contrast, the variable speed policy reduced NOx and PM10 pollution by 7.7 to 17.1% and 14.5 to 17.3%. As such, a variable speed policy appears to be a more effective environmental policy than reducing the speed limit to a maximum of 80 km/h.
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The western spread of raccoon rabies in Alabama has been slow and even appears to regress eastward periodically. While the disease has been present in the state for over 30 years, areas in northwest Alabama are devoid of raccoon rabies. This variation resulting in an enzootic area of raccoon rabies primarily in southeastern Alabama may be due to landscape features that hinder the movement of raccoons (i.e., gene flow) among different locations. We used 11 raccoon-specific microsatellite markers to obtain individual genotypes to examine gene flow among areas that were rabies free, enzootic with rabies, or had only sporadic reports of the disease. Samples from 70 individuals were collected from 5 sampling localities in 3 counties. The landscape feature data were collected from geographic information system (GIS) data. We inferred gene flow by estimating FST and by using Bayesian tests to identify genetic clusters. Estimates of pairwise FST indicated genetic differentiation and restricted gene flow between some sites, and an uneven distribution of genetic clusters was observed. Of the landscape features examined (i.e., land cover, elevation, slope, roads, and hydrology), only land cover had an association with genetic differentiation, suggesting this landscape variable may affect gene flow among raccoon populations and thus the spread of raccoon variant of rabies in Alabama.
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Traffic particle concentrations show considerable spatial variability within a metropolitan area. We consider latent variable semiparametric regression models for modeling the spatial and temporal variability of black carbon and elemental carbon concentrations in the greater Boston area. Measurements of these pollutants, which are markers of traffic particles, were obtained from several individual exposure studies conducted at specific household locations as well as 15 ambient monitoring sites in the city. The models allow for both flexible, nonlinear effects of covariates and for unexplained spatial and temporal variability in exposure. In addition, the different individual exposure studies recorded different surrogates of traffic particles, with some recording only outdoor concentrations of black or elemental carbon, some recording indoor concentrations of black carbon, and others recording both indoor and outdoor concentrations of black carbon. A joint model for outdoor and indoor exposure that specifies a spatially varying latent variable provides greater spatial coverage in the area of interest. We propose a penalised spline formation of the model that relates to generalised kringing of the latent traffic pollution variable and leads to a natural Bayesian Markov Chain Monte Carlo algorithm for model fitting. We propose methods that allow us to control the degress of freedom of the smoother in a Bayesian framework. Finally, we present results from an analysis that applies the model to data from summer and winter separately
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The purpose of this study was to develop and validate equations to estimate the aboveground phytomass of a 30 years old plot of Atlantic Forest. In two plots of 100 m², a total of 82 trees were cut down at ground level. For each tree, height and diameter were measured. Leaves and woody material were separated in order to determine their fresh weights in field conditions. Samples of each fraction were oven dried at 80 °C to constant weight to determine their dry weight. Tree data were divided into two random samples. One sample was used for the development of the regression equations, and the other for validation. The models were developed using single linear regression analysis, where the dependent variable was the dry mass, and the independent variables were height (h), diameter (d) and d²h. The validation was carried out using Pearson correlation coefficient, paired t-Student test and standard error of estimation. The best equations to estimate aboveground phytomass were: lnDW = -3.068+2.522lnd (r² = 0.91; s y/x = 0.67) and lnDW = -3.676+0.951ln d²h (r² = 0.94; s y/x = 0.56).
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Este estudo teve como objetivo desenvolver modelos preditores de fitomassa epigéa da vegetação arbórea da Floresta Baixa de Restinga. Foram selecionadas 102 árvores de 29 espécies ocorrentes na área de estudo e 102 indivíduos de jerivá (Syagrus romanzoffiana (Cham.) Glassman), distribuídos proporcionalmente entre as classes de diâmetro da vegetação arbórea. As árvores foram cortadas, ao nível do solo e foram medidos a altura total e o diâmetro à altura do peito (DAP) de cada árvore. As folhas foram separadas do lenho e a massa fresca da porção lenhosa e foliar medidas separadamente. Amostras de cada fração foram secas a 70 °C, até peso constante, para determinação da massa seca das árvores. Os modelos foram desenvolvidos através de análise de regressão linear, sendo a variável dependente a massa seca (MS) das árvores e as variáveis independentes a altura (h), o diâmetro a altura do peito (d) e as relações d² h e d² h multiplicada pela densidade da madeira (ρ d² h). Os modelos desenvolvidos indicam que o diâmetro explica grande parte da variabilidade da fitomassa das árvores da restinga e a altura é a variável explanatória da equação específica para o jerivá. Os modelos selecionados foram: ln MS (kg) = -1,352 + 2,009 ln d (R² = 0,96; s yx = 0,34) para a comunidade vegetal sem jerivá, ln MS (kg) = -2,052 + 0,801 ln d² h (R² = 0,94; s yx = 0,38) para a comunidade incluindo o jerivá, e ln MS (kg) = -0,884 + 2,40 ln h (R² = 0,92; s yx = 0,49) para o jerivá.
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Causal inference methods - mainly path analysis and structural equation modeling - offer plant physiologists information about cause-and-effect relationships among plant traits. Recently, an unusual approach to causal inference through stepwise variable selection has been proposed and used in various works on plant physiology. The approach should not be considered correct from a biological point of view. Here, it is explained why stepwise variable selection should not be used for causal inference, and shown what strange conclusions can be drawn based upon the former analysis when one aims to interpret cause-and-effect relationships among plant traits.