Transferência de tecnologia em práticas promotoras de rendimento de grãos de milho em instituições de ensino agrotécnico do Rio Grande do Sul e Santa catarina, safra 2004/2005.

bitstream/CNPT-2010/40665/1/p-do47.pd

Fine-mapping of 5q12.1-13.3 unveils new genetic contributors to caries

Caries is a multifactorial disease and little is still known about the host genetic factors influencing susceptibility. Our previous genome-wide linkage scan has identified the interval 5q12.1–5q13.3 as linked to low caries susceptibility in Filipino families. Here we fine-mapped this region in order to identify genetic contributors to caries susceptibility. Four hundred and seventy-seven subjects from 72 pedigrees with similar cultural and behavioral habits and limited access to dental care living in the Philippines were studied. DMFT scores and genotype data of 75 single-nucleotide polymorphisms were evaluated in the Filipino families with the Family-Based Association Test. For replication purposes, a total 1,467 independent subjects from five different populations were analyzed in a case-control format. In the Filipino cohort, statistically significant and borderline associations were found between low caries experience and four genes spanning 13 million base pairs (PART1, ZSWIM6, CCNB1, and BTF3). We were able to replicate these results in some of the populations studied. We detected PART1 and BTF3 expression in whole saliva, and the expression of BTF3 was associated with caries experience. Our results suggest BTF3 may have a functional role in protecting against caries.Fil: Shimizu, T.. Nihon University of Dentistry; JapónFil: Deeley, K.. University of Pittsburgh; Estados UnidosFil: Briseño Ruiz, J.. University of Pittsburgh; Estados UnidosFil: Faraco Junior, I. M.. University of Pittsburgh; Estados UnidosFil: Poletta, Fernando Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET.; ArgentinaFil: Brancher, J. A.. Pontifical Catholic University of Paraná; BrasilFil: Pecharki, G. D.. Pontifical Catholic University of Paraná; BrasilFil: Küchler, E. C.. Universidade Federal Fluminense; BrasilFil: Tannure, P. N.. Universidade Federal do Rio de Janeiro; BrasilFil: Lips, A.. Universidade Federal do Rio de Janeiro; BrasilFil: Vieira, T. C. S.. Universidade Federal Fluminense; BrasilFil: Patir, A.. Istanbul Medipol Universit; TurquíaFil: Yildirim, M.. Istanbul University; TurquíaFil: Mereb, J. C.. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; ArgentinaFil: Resick, J. M.. University of Pittsburgh; Estados UnidosFil: Brandon, C. A.. University of Pittsburgh; Estados UnidosFil: Cooper, M. E.. University of Pittsburgh; Estados UnidosFil: Seymen, F.. Istanbul University; TurquíaFil: Costa, M. C.. Universidade Federal do Rio de Janeiro; BrasilFil: Granjeiro, J. M.. Universidade Federal Fluminense; BrasilFil: Trevilatto, P. C.. Pontifical Catholic University of Paraná; BrasilFil: Orioli, I. M.. Universidade Federal do Rio de Janeiro; Brasil. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; ArgentinaFil: Castilla, Eduardo Enrique. Instituto Oswaldo Cruz; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET.; ArgentinaFil: Marazita, M. L.. University of Pittsburgh; Estados UnidosFil: Vieira, A. R.. University of Pittsburgh; Estados Unido

Kelvin-Helmholtz instability in the presence of variable viscosity for mudflow resuspension in estuaries

The temporal stability of a parallel shear flow of miscible fluid layers of dif- ferent density and viscosity is investigated through a linear stability analysis and direct numerical simulations. The geometry and rheology of this Newto- nian fluid mixing can be viewed as a simplified model of the behavior of mud- flow at the bottom of estuaries for suspension studies. In this study, focus is on the stability and transition to turbulence of an initially laminar configuration. A parametric analysis is performed by varying the values of three control pa- rameters, namely the viscosity ratio, the Richardson and Reynolds numbers, in the case of initially identical thickness of the velocity, density and viscosity profiles. The range of parameters has been chosen so as to mimic a wide variety of real configurations. This study shows that the Kelvin-Helmholtz instability is controlled by the local Reynolds and Richardson numbers of the inflection point. In addition, at moderate Reynolds number, viscosity strat- ification has a strong influence on the onset of instability, the latter being enhanced at high viscosity ratio, while at high Reynolds number, the influ- ence is less pronounced. In all cases, we show that the thickness of the mixing layer (and thus resuspension) is increased by high viscosity stratification, in particular during the non-linear development of the instability and especially pairing processes. This study suggests that mud viscosity has to be taken into account for resuspension parameterizations because of its impact on the inflec- tion point Reynolds number and the viscosity ratio, which are key parameters for shear instabilities

The different equations of motion of the central line of a slender vortex filament and their use to study perturbed vortices

A comparison between the equation of motion of the central line of a slender vortex filament deduced from a matched asymptotic expansion(A. Callegari and L. Ting) and the expansion of the equation of motion of the ad-hoc cut-off methods(S. Crow) with the cut-off length as the small asymptotic parameter is performed. It justifies the cut-off methods and gives the link between the cut-off lengths and the thickness of a viscous or inviscid vortex with an axial velocity component. The asymptotic equation of motion for an open filament is then simplified in case of a perturbed straight filament and different regimes are displayed. They depend of relatives values of the amplitude of the perturbation and the small thickness of the filament

Some Results on Simple Dynamo Systems

International audienceA homopolar dynamo for producing current impulses is described. Following the idea of Rioux (1964) and using the Moffatt's model (1979), the equations satisfied by the currents and the velocity are studied. The changing of variables and time scales to pass from one model to the other, and to the Lorenz's model if possible, are given. Finally, the trajectories of dynamo systems are analyzed in different phase spaces. The aim of this is to study the reliability of the topological analysis of. a signal delivered by different equivalent systems, embedded into different phase spaces. The topological properties of an experimental signal in a pseudo-phase space obtained by delaying the response can give information, particularly on the number of variables necessary to describe a complicated phenomenon

Weakly non-linear dynamics of thermoconvective instability involving viscoplastic fluids

International audienceIn this article, a weakly non-linear stability of viscoplastic fluid flow is performed. The system consists of a plane Rayleigh-Bénard Poiseuille (RBP) flow of a Bingham fluid. The basic flow is characterized by a central plug zone, of 2yb width, in which the stresses are smaller than the Bingham number B, the dimensionless yield stress. The Bingham model assumes that inside this zone the material moves as a rigid solid and that outside this zone, it behaves as a viscous fluid. The aim of this study is to investigate the influence of the yield stress on the instability conditions. The linear stability analysis is performed using a modal method and provides critical values of Rayleigh and wave numbers, from which the system becomes unstable. The critical mode, i.e. the least stable mode, is also determined. This mode, also called the fundamental mode creates perturbation harmonics which cannot be neglected above criticality. The weakly non-linear analysis is performed for small amplitude perturbations. In this study, the quadratic modes of the perturbation are determined. Results indicate that the non-linear modes perturbation can attain high maximal values which is the consequence of the high variations of viscosity in the flow. The characterization of the complex Landau equation sheds light on a transition in terms of the bifurcation nature above a critical Peclet number Pe_c = O(1). Below Pe_c , it is found that a supercritical equilibrium state could exist, such as in the Newtonian case, while above Pe_c , the bifurcation becomes subcritical. One observes a sharp transition from supercritical to subcritical bifurcation as the Peclet value is increased. A dependence of Pe_c on the yield stress is highlighted since the subcritical bifurcation is first observed for weak values of yb (yb O(10^(−1)), the change of the bifurcation nature is due to the variations of the effective viscosity in the unyielded regions

Lateral forces on a magnet falling in a conducting pipe

International audiencePurpose — The purpose of this paper is to investigate the lateral forces during the fall of a magnet in a conducting pipe, when the direction of magnetization of the magnet is fixed. If the direction of magnetization is not parallel to the axis of the pipe, lateral forces occur and a decentration of the magnet happens.Design/methodology/approach — The problem is studied numerically, with a T − h 3D FE formulation well-suited for the problem. Computational results are compared with experimental results.Findings — The physical model is given and the main force coefficients analyzed. The lateral forces and the decentration phenomenon are studied as a function of the main parameters (thickness and radius of the pipe).Originality/value — The direction of magnetization is a key parameter to analyze the dynamics of a magnet motion inside a conducting pipe, when the radii of the pipe and the magnet are not so close. This analysis with a fixed direction of magnetization allows to quantify the lateral forces and the decentration, and is a first step to understand the complete motion which includes the rotation which can be linked to the decentration

Stabilisation d'un écoulement plan par stratification de la viscosité

On examine la possibilité de retarder la transition vers la turbulence à partir d'une stratification en viscosité. A titre de problème prototype, une analyse linéaire de stabilité de l'écoulement de Poiseuille plan d'un fluide rhéofluidifiant décrit par le modèle de Carreau est effectuée. Les résultats issus des approches modale et non modale montrent d'une part qu'il est fondamental de prendre en compte la perturbation de la viscosité et d'autre part que la stratification en viscosité peut être considérée comme un moyen viable pour retarder la transition