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In this work, we investigate the dynamics of the wave packet traveling through a porous semiconductor channel, with the defects being simulated by a disordered scattering region produced by obstruction potentials. The theoretical framework is based on the $split-operator$ technique to solve the time-dependent Schr$\"o$dinger equation within the effective mass approximation. In our simulation, we consider the semiconductor channel made by InGaAs with a width of 100 angstrom, growth on an InAlAs substrate, and the porous ones with circular symmetry and different densities. The results for the current probability density and reflection, and transmission coefficients are analyzed for different initial values of the kinetic energy of the Gaussian wave packet, disordered pore densities, and pore randomness., Comment: The title of the work will have to be changed and the results will have to be more widely discussed

Este estudo apresenta uma visão etnográfica de três funções representativas do Estado: o poder político personificado nos deputados à Assembleia da República; o poder judicial personificado nos magistrados ou oficiais de justiça de dois tribunais de primeira instância; e a gestão do ambiente levada a cabo pelos técnicos da Agência Portuguesa do Ambiente. Metodologicamente apoiado em trabalho de campo intensivo com recurso à observação participante, procurando dar primazia às pessoas que, quotidianamente, fazem do Estado uma realidade concreta e actuante, o estudo retrata e analisa os meandros do funcionamento daquelas quatro instituições, procurando compreender o trabalho dos seus agentes nas suas vertentes interaccionais, sociotécnicas e culturais.

Complex geological mixtures of rock inclusions randomly distributed in a weaker matrix can raise challenging issues for a proper geomechanical characterization. These materials, also referred as bimrocks, are widespread all around the world and can be recognized in a vast range of geological formations. Although most of these formations are assumed to be controlled by the matrix mechanical properties, several studies, instead, showed that the overall behavior is strongly influenced by the presence of the rock fragments and, in particular, by their volumetric content. In the present study, the overall mechanical behavior and strength characteristics of rock mixtures during triaxial tests were studied using a 3-D finite element. A script routine was specifically developed for the 3-D model generation. Given a specific volumetric content and preferred inclusion orientation, the routine generates cylindrical specimens with ellipsoidal inclusions. Ellipsoidal surface intersections are governed by applying an algebraic separation condition which states the contact condition between two inclusions (i.e., separated, overlapped, or overlapped at a single point). The preliminary FEM analysis on specimens with spherical inclusions indicated a marked influence of the inclusion’s volumetric content on the mechanical properties of the bimrock. Different behaviors were observed for welded and unwelded specimens. Further studies will focus on the effect of ellipsoidal inclusions.

The damaging effects of neuwiedase, a non-hemorrhagic snake venom metalloproteinase from P-I class, on gastrocnemius muscle are studied herein. Following neuwiedase injection, ultrastructural alterations were detected early showing disarrangement of skeletal muscle fibers (characterized by discontinuity of Z lines), mitochondrial swelling, and disruption of plasma membrane and basal lamina. Degradation of skeletal muscle and the appearance of an amorphous substance, primarily composed of cellular debris, were noted after 24 hours. The presence of neuwiedase at the injection site (detected by immunocytochemistry) revealed highly specific labeling of myofibril components of damaged myocytes. In addition, proteolysis of muscle proteins assayed through myofibrils extracted from gastrocnemius muscle indicated that neuwiedase provoked degradation of myofibrils, especially myosin. These results suggest that skeletal muscle damage, induced by neuwiedase, is probably due to its proteolytic action on myofibrils, which are responsible for the maintenance of the cellular architecture.