Políticas sociais e luta de classes: uma crítica a Amartya Sen = Social policies and the class struggle: criticizing Amartya Sen

O artigo desenvolve o argumento de que as políticas econômicas e sociais adotadas pelo Banco Mundial, tal como desenvolvida por Amartya Sen, não resolvem o problema da pobreza dos países subdesenvolvidos. Os pressupostos dessa teoria e as condições de vida das populações envolvidas acabam por justificar moralmente tais políticas, não se constituindo numa alternativa verdadeira de políticas sociais. Além disso, reproduz-se uma opção ideológica e política que desconhece a exploração capitalista e suas principais características. A alternativa marxista coloca-se, portanto, como uma alternativa de interpretaçã

Ultra-short solitons and kinetic effects in nonlinear metamaterials

We present a stability analysis of a modified nonlinear Schroedinger equation describing the propagation of ultra-short pulses in negative refractive index media. Moreover, using methods of quantum statistics, we derive a kinetic equation for the pulses, making it possible to analyze and describe partial coherence in metamaterials. It is shown that a novel short pulse soliton, which is found analytically, can propagate in the medium.Comment: 6 pages, 2 figures, to appear in Phys. Rev.

Classical Rotons in Cold Atomic Traps

We predict the emergence of a roton minimum in the dispersion relation of elementary excitations in cold atomic gases in the presence of diffusive light. In large magneto-topical traps, multiple-scattering of light is responsible for the collective behavior of the system, which is associated to an effective Coulomb-like interaction between the atoms. In optically thick clouds, the re-scattered light undergoes diffusive propagation, which is responsible for a stochastic short-range force acting on the atoms. We show that the dynamical competition between these two forces results on a new polariton mode, which exhibits a roton minimum. Making use of Feynman's formula for the static structure factor, we show that the roton minimum is related to the appearance of long-range order in the system.Comment: 5 pages, 3 figure

The effect of simultaneously presented words and auditory tones on visuomotor performance

The experiment reported here used a variation of the spatial cueing task to examine the effects of unimodal and bimodal attention-orienting primes on target identification latencies and eye gaze movements. The primes were a nonspatial auditory tone and words known to drive attention consistent with the dominant writing and reading direction, as well as introducing a semantic, temporal bias (past–future) on the horizontal dimension. As expected, past-related (visual) word primes gave rise to shorter response latencies on the left hemifield and future-related words on the right. This congruency effect was differentiated by an asymmetric performance on the right space following future words and driven by the left-to-right trajectory of scanning habits that facilitated search times and eye gaze movements to lateralized targets. Auditory tone prime alone acted as an alarm signal, boosting visual search and reducing response latencies. Bimodal priming, i.e., temporal visual words paired with the auditory tone, impaired performance by delaying visual attention and response times relative to the unimodal visual word condition. We conclude that bimodal primes were no more effective in capturing participants’ spatial attention than the unimodal auditory and visual primes. Their contribution to the literature on multisensory integration is discussed.info:eu-repo/semantics/acceptedVersio

Asymmetric practices of reading and writing shape visuospatial attention and discrimination

Movement is generally conceived of as unfolding laterally in the writing direction that one is socialized into. In 'Western' languages, this is a left-to-right bias contributing to an imbalance in how attention is distributed across space. We propose that the rightward attentional bias exercises an additional unidirectional influence on discrimination performance thus shaping the congruency effect typically observed in Posner-inspired cueing tasks. In two studies, we test whether faces averted laterally serve as attention orienting cues and generate differences in both target discrimination latencies and gaze movements across left and right hemifields. Results systematically show that right-facing faces (i.e. aligned with the script direction) give rise to an advantage for cue-target pairs pertaining to the right (versus left) side of space. We report an asymmetry between congruent conditions in the form of right-sided facilitation for: (a) response time in discrimination decisions (experiment 1-2) and (b) eye-gaze movements, namely earlier onset to first fixation in the respective region of interest (experiment 2). Left and front facing cues generated virtually equal exploration patterns, confirming that the latter did not prime any directionality. These findings demonstrate that visuospatial attention and consequent discrimination are highly dependent on the asymmetric practices of reading and writing.Fundação para a Ciência e Tecnologia - FCTinfo:eu-repo/semantics/publishedVersio

INFLUENCE OF ASPECT RATIO IN THE TURBULENT CONVECTION IN CAVITIES

The purpose of this study is to know the air distribution in a conditioned room, through the numerical investigation of the influence of aspect ratio in the thermal and fluid dynamics behavior of a turbulent flow. To achieve that objective, some simulations were done of the flow inside a rectangular room, where the air enters through an opening in the top of one wall and leaves the room through an opening in the bottom of the opposite wall. The Reynolds mean equations are used, with the turbulence model RSM BSL (Reynolds Stress Model - Baseline) to solve four cases, with different geometries. It was concluded that, in general, the turbulence model used in this work is capable to predict quite well the fluid dynamics behavior of the flow, which is influenced by the room length, but not by its width

Caucasian Familial Moyamoya Syndrome With Rare Multisystemic Malformations

Moyamoya disease is an idiopathic progressive steno-occlusive disorder of the intracranial arteries located at the base of the brain. It is associated with the development of compensatory extensive network of fine collaterals. Moyamoya disease is considered syndromic when certain genetic or acquired disorders such as polycystic kidney disease, neurofibromatosis, or meningitis are also present. Although the genetic contribution in moyamoya is indisputable, its cause and pathogenesis remain under discussion. Herein, we report a rare occurrence of moyamoya syndrome in two European Caucasian siblings in association with unusual multisystemic malformations (polycystic kidney disease in one, and intestinal duplication cyst in the other). The karyotype was normal. No mutation in the RFN213 gene was found, and none of the HLA types linked to moyamoya disease or described in similar familial cases were identified. By describing these multisystemic associations, polycystic kidney disease for the second time, and intestinal malformation for the first time in the literature, our report expands the phenotypic variability of moyamoya syndrome. The coexistence of disparate malformations among close relatives suggests an underlying common genetic background predisposing to structural or physiological abnormalities in different tissues and organs

Modeling and simulation of wetted porous thermal barriers operating under high temperature or high heat flux

Porous media with high water content can be successfully used as thermal barriers to operate under high exposure temperatures and/or high heat fluxes. Modeling and simulation of such systems presents difficulties and challenges, which are pointed and worked out in this work. Liquid water and water vapor transfers are considered, including the capillary effects for the liquid phase, as well as the air transfer inside the porous medium. Heat transfer model includes conduction, radiation, enthalpy convection, sensible heating and phase change. A realistic model is considered at the exposed boundary in what concerns mass transfer: the outflow mass transfer is dictated by the water effusion and not by the convection transfer mechanism between the exposed surface and the environment. A set of numerical aspects is detailed, concerning both the numerical modeling and the solution of the discretization equations, which are crucial to obtain successful simulations. Some illustrative results are presented, showing the potential of the wetted porous media when used as thermal barriers, as well as the capabilities of the presented physical and numerical models to deal with such systems.http://www.sciencedirect.com/science/article/B6V3H-4RKDHVC-2/1/633ef2cefc7a7e2178f1d59743e3d24