The modulated spin liquid: a new paradigm for URu2_2Si2_2

We argue that near a Kondo breakdown critical point, a spin liquid with spatial modulations can form. Unlike its uniform counterpart, we find that this occurs via a second order phase transition. The amount of entropy quenched when ordering is of the same magnitude as for an antiferromagnet. Moreover, the two states are competitive, and at low temperatures are separated by a first order phase transition. The modulated spin liquid we find breaks $Z_4$ symmetry, as recently seen in the hidden order phase of URu$_2$Si$_2$. Based on this, we suggest that the modulated spin liquid is a viable candidate for this unique phase of matter.Comment: 4 pages, 2 figure

Convergence of simple adaptive Galerkin schemes based on h − h/2 error estimators

We discuss several adaptive mesh-refinement strategies based on (h − h/2)-error estimation. This class of adaptivemethods is particularly popular in practise since it is problem independent and requires virtually no implementational overhead. We prove that, under the saturation assumption, these adaptive algorithms are convergent. Our framework applies not only to finite element methods, but also yields a first convergence proof for adaptive boundary element schemes. For a finite element model problem, we extend the proposed adaptive scheme and prove convergence even if the saturation assumption fails to hold in general

CFD STUDIO: AN EDUCATIONAL SOFTWARE FOR CFD ANALYSIS

The main goal of this paper is to demonstrate the general characteristics of the educational user-friendly CFD Studio package for CFD teaching. The package was designed for teaching 2D fluid mechanics and heat transfer process, including conduction, coupled conduction/convection, natural and forced convection, external and internal flows, among other phenomena. The finite volume methodology and its related topics can also be taught using the software. Therefore, general aspects of the three main modules, pre-processor, solver and post-processor are discussed aiming to show the generality of the tool. These modules are integrated in the application by a so-called numerical problem project which guide the student through the steps to obtain the solution. To approximate the partial differential equations the finite volume approach is employed using a fully-implicit formulation with the interpolation schemes CDS, UDS and WUDS. Mesh editing and nonorthogonal boundary-fitted mesh generation, using algebraic interpolation and elliptic equations, are important features of the package. Coupled heat transfer problems are handled using the solid-block formulation and the pressure-velocity coupling uses the SIMPLE and SIMPLEC methods with non-staggered grids. To demonstrate the capabilities two fluid flow and heat transfer problem projects are presented

Spatial variability of soil fertility attributes and productivity in a coffee crop farm

ArticleCoffee cultivation is of great importance to Brazilian agribusiness, as coffee occupies extensive production areas and is one of the most exported Brazilian products. To maintain coffee production numbers, productive techniques must be adopted that optimize productive system use. The objective of this work was to apply geostatistical techniques in the evaluation of soil fertility attributes to construct maps of variability in soil fertility parameters and the productivity of a coffee crop in the municipality of Monte Carmelo, Minas Gerais (MG), Brazil. The work was developed with coffee of the cultivar Mundo Novo 379/19, and 19 sample points were georeferenced in Universal Transverse Mercator coordinates. Spatial dependence of the fertility and productivity parameters was analysed via classic semivariogram fitting and interpolation by ordinary kriging using the statistical computer system, R. All parameters evaluated showed high degrees of spatial dependence. The attribute values varied along the sampling points, except for the sodium (Na) contents, which had similar values in all samplings. The studied parameters ranged from 80 to 200 metres. It is conclusion, the use of productivity maps linked to soil chemical attributes can be useful for determining the occurrence of variable productivity rates throughout the area, allowing the adoption of corrective practices for subsequent crops and thus making the maps very useful tools for producers

Retinolemia em escolares eutróficos e com sobrepeso

Objectives: To determine the frequency of normal weight and overweight schoolchildren who have deficiency of vitamin A and to study the relationship between serum retinol concentrations and body mass index (BMI), body fat percentage and waist circumference of normal weight and overweight children. Methods: Cross-sectional, descriptive and analytical study carried out with schoolchildren aged 8 to 10 years old from public schools in Uberaba (MG). The sample consisted of eighty students matched for age and sex, being forty eutrophic schoolchildren and forty with overweight. Results: It was observed that 25% of students were overweight and 20% of normal weight children presented serum retinol disabled. There was no significant difference between the mean serum retinol concentrations in the eutrophic schoolchildren group and overweight group. No significant correlations were observed between serum concentrations and BMI, waist circumference and body fat percentage measured by bioelectrical impedance in both groups. Conclusion: The results show a high prevalence of deficient serum retinol, which are not related to body fat percentage and waist circumference measurement, in two groups of healthy schoolchildren, an eutrophic and another group, overweight

Validação factorial do 'Spanish Burnout Inventory' em polícias portugueses.

This study was designed to assess the factor structure of the Spanish Burnout Inventory in a sample of 245 Portuguese police officers working in Lisbon. Using exploratory factor analysis (EFA), 4 factors were extracted, reproducing the original model: Enthusiasm toward the job (5 items), Psychological exhaustion (4 items), Indolence (6 items), and Guilt (5 items). However, item 20 -designed to assess Guilt- was grouped with both items of Indolence and Psychological exhaustion. The results of the study support the factor validity of the SBI and the adequate internal consistency of its dimensions, with Cronbach Alpha higher than .70. The results suggest that SBI is an adequate instrument to assess burnout in Portuguese police officers

Tecnologia para Decorticação da Castanha de Caju.

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