Curvatura Da Superfície E Seu Efeito Na Variabilidade Espacial Dos Atributos Do Solo, Pinheiral - Rj/br

Understanding the spatial variability of soil chemical and physical attributes is important for improving management practices and soil conservation. In turn, the spatial variability of soil properties results from variation in morphological relief characteristics. Thus, the purpose of this study was to evaluate the influence of landform curvature on the spatial variability of soil chemical and physical attributes in the Mar de Morros region (Pinheiral-Rio de Janeiro State, Brazil). Two adjacent landforms were selected with convex and concave curvature and sampled in a regularly spaced grid of 10 meters. A total of 56 soil samples (0-5 cm depth) from the two landforms were collected and analyzed for physical and chemical attributes. The data were analyzed using descriptive statistics and geostatistics. All chemical attributes showed random patterns of spatial variability in both landforms. The concave landform had higher values of pH and potassium and lower values of aluminum than the convex landform. In contrast, silt content showed spatial dependence in both the concave and convex landforms. Bulk density and clay showed spatial dependence in the convex landform. Bulk density and silt content increased from the shoulder to the footslope of both landforms. The results show that, for this study area, landform curvature has more influence on the spatial dependence of soil physical attributes than of soil chemical properties. © 2016, Federal University of Lavras. All rights reserved.22443143

Modelo para el tratamiento de la deuda técnica orientado a la evolución de los componentes para que las aplicaciones sean sostenibles a largo plazo

La Deuda Técnica es un fenómeno habitual del proceso de construcción de software, la cual es reconocida como un conjunto de malas prácticas y decisiones incorrectas en la fase de construcción de software, aceptada generalmente como efecto colateral en proyectos de software donde puede existir presiones de cronograma y con entregas continuas de valor a corto plazo. Ciertos aspectos de este fenómeno son conocidos de forma general, lo que sigue sin conocerse en profundidad, es cómo la deuda técnica se manifiesta y afecta específicamente los procesos de software, y cómo las técnicas de desarrollo de software empleadas acomodan o mitigan la presencia de esta deuda (Holvitie et al., 2018). La deuda técnica ha ganado visibilidad en los últimos años debido al interés en los proyectos de software que usan marcos de desarrollo ágil, los cuales detallan la responsabilidad que tienen los equipos de desarrollo en producir código de calidad, y que en su afán de entregar software funcionando en el menor tiempo posible, renuncian a actividades relacionadas con la producción de código de calidad, como son, el uso de buenas prácticas de codificación, definiciones de diseños y arquitecturas incompletas, poca cobertura de pruebas y documentación, entre otros, que a largo plazo acumulan una gran cantidad de deuda técnica que se vuelve perjudicial para el éxito de los proyectos. Parte de este estudio es comprender los antecedentes, dimensiones, atributos y consecuencias de la deuda técnica, para así poder proponer un modelo de referencia para el tratamiento de la deuda técnica, y cómo puede éste ser adaptado como parte de un proceso de madurez similar a los existentes en desarrollo de software general. El entendimiento de las causas para lograr que las aplicaciones puedan ser sostenibles a largo plazo, será el principal enfoque para la selección de las principales técnicas para el tratamiento de la deuda técnica definidas en la literatura, las tecnologías y herramientas que serán útiles para registrar y hacer las mediciones de deuda técnica, especificar qué actividades y ejemplos claros de cómo deberían ser implementadas según el modelo por parte de los equipos de desarrollo, contribuyendo a reducir y gestionar la deuda técnica en las aplicaciones. El modelo propuesto debe proporcionar un enfoque útil para comprender y gestionar la deuda técnica con fines prácticos, que involucre futuras líneas de investigación.Technical Debt is a common phenomenon of the software construction process, the quality is recognized as a set of bad practices and incorrect decisions in the software construction phase, normally accepted as a side effect in software projects where there may be schedule difficulties and with continuous deliveries of short-term value. Certain aspects of this phenomenon are generally known, what remains unknown in depth, is how technical debt manifests and specifically affects software processes, and how the software development techniques used accommodate or mitigate the presence of this debt (Holvitie et al., 2018).Technical debt has gained visibility in recent years due to interest in software projects that use agile development frameworks, which detail the responsibility that development teams have in producing quality code, and that in their eagerness to deliver software functioning in the shortest possible time, they give up activities related to the production of quality code, such as the use of good coding practices, definitions of incomplete designs and architectures, little evidence and documentation coverage, among others, that over term accumulate a large amount of technical debt that becomes detrimental to the success of the projects. Part of this study is to understand the background, dimensions, attributes and consequences of technical debt, in order to propose a reference model for the treatment of technical debt, and how it can be adapted as part of a maturity process similar to those existing in general software development. Understanding the causes to ensure that applications can be sustainable in the long term will be the main approach for the selection of the main techniques for the treatment of technical debt defined in the literature, the technologies and tools that will be useful for recording and make the measurements of technical debt, specify what activities and clear examples of how they should be implemented according to the model by the development teams, contributing to reduce and manage the technical debt in the applications. The proposed model should provide a useful approach to understand and manage technical debt for practical purposes, which involves future lines of research.Magíster en Ingeniería de SoftwareMaestrí

QCD Corrections to QED Vacuum Polarization

We compute QCD corrections to QED calculations for vacuum polarization in background magnetic fields. Formally, the diagram for virtual $e\bar{e}$ loops is identical to the one for virtual $q\bar{q}$ loops. However due to confinement, or to the growth of $\alpha_s$ as $p^2$ decreases, a direct calculation of the diagram is not allowed. At large $p^2$ we consider the virtual $q\bar{q}$ diagram, in the intermediate region we discuss the role of the contribution of quark condensates \left and at the low-energy limit we consider the $\pi^0$, as well as charged pion $\pi^+\pi^-$ loops. Although these effects seem to be out of the measurement accuracy of photon-photon laboratory experiments they may be relevant for $\gamma$-ray burst propagation. In particular, for emissions from the center of the galaxy (8.5 kpc), we show that the mixing between the neutral pseudo-scalar pion $\pi_0$ and photons renders a deviation from the power-law spectrum in the $TeV$ range. As for scalar quark condensates \left and virtual $q\bar{q}$ loops are relevant only for very high radiation density $\sim 300 MeV/fm^3$ and very strong magnetic fields of order $\sim 10^{14} T$.Comment: 15 pages, 4 figures; Final versio

Quantification of milk adulterants (starch, H2O2, and NaClO) using colorimetric assays coupled to smartphone image analysis

In this paper, a colorimetric method for the detection of milk adulterants using smartphone image analysis is reported. This is based on the reactions to detect hydrogen peroxide, sodium hypochlorite, and starch in milk, where a color variation is observed for each substance. The image analysis was performed by using lab-made apps (PhotoMetrix®, and RedGIM®) based on partial least squares regression with the histograms of the red-green-blue images. The image histograms are automatically calculated using the smartphone camera and processed within the app. The results have shown the capability of this method to predict the concentration of the three adulterants, demonstrating the potential of the use of digital images and smartphone applications associated with chemometric tools. This method presents a fast, low-cost, and portable way to quantify adulterants in Cow milk

Maternal prenatal anxiety and the fetal origins of epigenetic aging

Stress and Psychopatholog