Exercício Físico no tratamento da Espondilite Anquilosante: uma revisão sistemática

O exercício físico é um componente regular no tratamento de várias patologias, entre as quais a espondilite anquilosante (EA). A EA é uma patologia reumática, crónica e sistémica, sem cura conhecida e na qual o exercício físico se tem revelado como terapia essencial no controlo e prevenção de deformidades associadas. No sentido de promover uma prática de acordo com a evidência e de ajudar na tomada de decisões acerca dos cuidados de saúde em pacientes com EA, foi efectuada uma revisão de estudos randomizados controlados tendo por objectivo examinar o papel do exercício físico no tratamento de pacientes com EA. Uma pesquisa computorizada nas bases de dados Cochrane Central,Pubmed/ Medline e PEDro permitiu identificar 13 estudos envolvendo 1.056 pacientes, com classificação metodológica de 5,62 na escala de PEDro. Dos estudos incluídos, 3 avaliaram o efeito aditivo do exercício físico à medicação, 3 compararam os benefícios da prática regular de exercício supervisionado em grupo com os benefícios do exercício físico não supervisionado no domicílio, 5 avaliaram programas de exercício alternativo (hidroterapia e reeducação postural global) ao programa tradicionalmente usado em pacientes do EA e 2 centraram-se sobre o rácio custo/efectividade da terapia. Os estudos incluídos nesta revisão sugerem que o exercício físico é uma terapia benéfica no tratamento de pacientes com EA; este exercício deve ser efectuado em grupo com supervisão de fisioterapeuta. Novas modalidades de exercício, hidroterapia ou exercício baseado na reeducação postural global, parecem oferecer igualmente uma terapia alternativa válida e promissora para pacientes com EA

Numerical solution of linear models in economics: The SP-DG model revisited

In general, complex and large dimensional models are needed to solve real economic problems. Due to these characteristics, there is either no analytical solution for them or they are not attainable. As a result, solutions can be only obtained through numerical methods. Thus, the growing importance of computers in Economics is not surprising. This paper focuses on an implementation of the SP-DG model, using Matlab,developed by the students as part of the Computational Economics course. We also discuss some of our teaching/learning experience within the course, given for the first time in the FEP Doctoral Programme in Economics.SP-DG Model, Output, Inflation, Numerical Simulation, Teaching of Economics

On the geometry of Riemannian cubic polynomials

AbstractWe continue the work of Crouch and Silva Leite on the geometry of cubic polynomials on Riemannian manifolds. In particular, we generalize the theory of Jacobi fields and conjugate points and present necessary and sufficient optimality condition

Oscillatory behavior of two nonlinear microbial models of soil carbon decomposition

A number of nonlinear models have recently been proposed for simulating soil carbon decomposition. Their predictions of soil carbon responses to fresh litter input and warming differ significantly from conventional linear models. Using both stability analysis and numerical simulations, we showed that two of those nonlinear models (a two-pool model and a three-pool model) exhibit damped oscillatory responses to small perturbations. Stability analysis showed the frequency of oscillation is proportional to √(ε⁻¹-1) Ks/Vs in the two-pool model, and to √(ε⁻¹-1) Kl/Vl in the three-pool model, where ε is microbial growth efficiency, Ks and Kl are the half saturation constants of soil and litter carbon, respectively, and /Vs and /Vl are the maximal rates of carbon decomposition per unit of microbial biomass for soil and litter carbon, respectively. For both models, the oscillation has a period of between 5 and 15 years depending on other parameter values, and has smaller amplitude at soil temperatures between 0 and 15°C. In addition, the equilibrium pool sizes of litter or soil carbon are insensitive to carbon inputs in the nonlinear model, but are proportional to carbon input in the conventional linear model. Under warming, the microbial biomass and litter carbon pools simulated by the nonlinear models can increase or decrease, depending whether ε varies with temperature. In contrast, the conventional linear models always simulate a decrease in both microbial and litter carbon pools with warming. Based on the evidence available, we concluded that the oscillatory behavior and insensitivity of soil carbon to carbon input are notable features in these nonlinear models that are somewhat unrealistic. We recommend that a better model for capturing the soil carbon dynamics over decadal to centennial timescales would combine the sensitivity of the conventional models to carbon influx with the flexible response to warming of the nonlinear model.15 page(s

Physical properties of single-crystalline fibers of the colossal-magnetoresistance manganite La0.7Ca0.3MnO3

We have grown high-quality single crystals of the colossal-magnetoresistance (CMR) material La0.7Ca0.3MnO3 by using the laser heated pedestal growth (LHPG) method. Samples were grown as fibers of different diameters, and with lengths of the order of centimeters. Their composition and structure were verified through X-ray diffraction, scanning electron microcopy with EDX (Energy Dispersive X-ray Analysis) and by Rietveld analysis. The quality of the crystalline fibers was confirmed by Laue and EBSD (Electron Backscatter Diffraction) patterns. Rocking curves performed along the fiber axis revealed a half-height width of 0.073 degrees. The CMR behavior was confirmed by electrical resistivity and magnetization measurements as a function of temperature.Comment: 11 pages (including 3 figures); to appear in Appl. Phys. Let