Thrust Vectoring of a Fixed Axisymmetric Supersonic Nozzle Using the Shock-Vector Control Method

The application of the Shock Vector Control (SVC) approach to an axysimmetric supersonic nozzle is studied numerically. SVC is a Fluidic Thrust Vectoring (FTV) strategy that is applied to fixed nozzles in order to realize jet-vectoring effects normally obtained by deflecting movable nozzles. In the SVC method, a secondary air flow injection close to the nozzle exit generates an asymmetry in the wall pressure distribution and side-loads on the nozzle, which are also lateral components of the thrust vector. SVC forcing of the axisymmetric nozzle generates fully three-dimensional flows with very complex structures that interact with the external flow. In the present work, the experimental data on a nozzle designed and tested for a supersonic cruise aircraft are used for validating the numerical tool at different flight Mach numbers and nozzle pressure ratios. Then, an optimal position for the slot is sought and the fully 3D flow at flight Mach number M∞=0.9 is investigated numerically for different values of the SVC forcing

Numerical and Experimental Assessment of a Linear Aerospike

In the present work a linear aerospike nozzle model has been studied with cold flow experiments in various working conditions. A series of numerical 3D RANS simulations have been performed in order to directly compare numerical and experimental results. Mean pressure distributions have been measured on the nozzle model symmetry plane, in order to characterize the flow evolution along the walls of the plug. The presented results show a good agreement between numerical and experimental results

steroid resistant minimal change disease with ballooned podocytes

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Maximally-localized Wannier functions for disordered systems: application to amorphous silicon

We use the maximally-localized Wannier function method to study bonding properties in amorphous silicon. This study represents, to our knowledge, the first application of the Wannier-function analysis to a disordered system. Our results show that, in the presence of disorder, this method is extremely helpful in providing an unambiguous picture of the bond distribution. In particular, defect configurations can be studied and characterized with a novel degree of accuracy that was not available before.Comment: 4 pages, with 3 PostScript figures embedded. Uses RevTex and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/index.html#nm_as

Genetic background of mitral valve prolapse

Mitral valve prolapse (MVP) has a prevalence of 2-3% among the population. It involves a heterogeneous group of patients with different expressions and according to the phenotype can be further divided into fibroelastic deficiency, which is mainly considered as a degeneration due to aging, and myxomatous disease, frequently associated with familiar clusters. Thus, MVP can be present in syndromic, when part of a well-defined syndrome, and non-syndromic forms. The latter occurs more often. To the second belong both familiar and isolated or sporadic forms. On one hand, among familial forms, although X-linked transmission related t

From band insulator to Mott insulator in one dimension

We derive the phase diagram for the one-dimensional model of a ferroelectric perovskite recently introduced by Egami, Ishihara and Tachiki [Science, {\bf 261}, 1307 (1993)]. We show that the interplay between covalency, ionicity and strong correlations results in a spontaneously dimerized phase which separates the weak-coupling band insulator from the strong-coupling Mott insulator. The transition from the band insulator to the dimerized phase is identified as an Ising critical point. The charge gap vanishes at this single point with the optical conductivity diverging as $\sigma(\omega)\sim \omega^{-3/4}$. The spin excitations are gapless above the second transition to the Mott insulator phase.Comment: 4 pages LaTex (RevTex) and 1 postscript figure included by eps

A quantum Monte Carlo study of the one-dimensional ionic Hubbard model

Quantum Monte Carlo methods are used to study a quantum phase transition in a 1D Hubbard model with a staggered ionic potential (D). Using recently formulated methods, the electronic polarization and localization are determined directly from the correlated ground state wavefunction and compared to results of previous work using exact diagonalization and Hartree-Fock. We find that the model undergoes a thermodynamic transition from a band insulator (BI) to a broken-symmetry bond ordered (BO) phase as the ratio of U/D is increased. Since it is known that at D = 0 the usual Hubbard model is a Mott insulator (MI) with no long-range order, we have searched for a second transition to this state by (i) increasing U at fixed ionic potential (D) and (ii) decreasing D at fixed U. We find no transition from the BO to MI state, and we propose that the MI state in 1D is unstable to bond ordering under the addition of any finite ionic potential. In real 1D systems the symmetric MI phase is never stable and the transition is from a symmetric BI phase to a dimerized BO phase, with a metallic point at the transition

Culture permeating the feelings and the reactions in the face of pain

Este estudo descreve a percepção e os significados da dor em adultos usuários do SUS. A popu-lação compreendeu 60 pacientes que buscaram o serviço no período. A pesquisa foi do tipo exploratório-descritiva, cujos dados foram coletados com entrevista semi-estruturada e analisados qualitativamente, constituindo temas que emergiram, sendo agrupados por categorias. Evidenciou-se que "o significado da dor" revelou o predomínio do entendimento da dor como uma questão física; apontou a dor relacionada também a questões emocionais e sentimentais, religiosas e humanas. "A reação de homens e mulheres frente à dor" é percebida diferentemente conforme o sexo feminino e masculino. Em "como você se sente nas situações em que tem dor?", as respostas variaram entre afetivas, cognitivas e comportamentais.Em este estudio se describe la percepción y los significados del dolor en adultos usuarios del Sistema Único de Salud (SUS). La población comprendió 60 pacientes que buscaron el servicio en el período. La investigación fue de tipo descriptivo exploratorio, cuyos datos fueron recolectados con una entrevista semi-estructurada y analizados cualitativamente, constituyendo temas que emergieron siendo agrupados por categorías. Se evidenció que "el significado del dolor" reveló el predominio del entendimiento del dolor como una cuestión física; apuntó el dolor relacionado también a cuestiones emocionales y sentimentales, religiosas y humanas. "La reacción de hombres y mujeres frente al dolor" es percibida de manera diferente conforme el sexo femenino y masculino. En "cómo se siente en situaciones en que tiene dolor?", las respuestas variaron entre afectivas, cognitivas y de comportamiento.This study describes the perception of pain and the meanings it has for adults who use the Brazilian public health system, the Sistema Único de Saúde (SUS). The sample was comprised of 60 patients who sought the service in the period. This is a descriptive-explanatory research whose data were collected through semi-structured interviews and evaluated qualitatively. The emerging themes were grouped into categories. It was observed that "the meaning of pain" revealed the preponderance of the comprehen-sion of pain as a physical matter. It also showed that pain is related to emotional, sentimental, religious and human circumstances as well. "The reaction of men and women in the face of pain" is perceived differently according to the gender. In questions such as "How do you feel when you are in pain?" the answers varied between affective, cognitive and behavioral

SARS-CoV-2 and Skin: The Pathologist's Point of View

The SARS-CoV-2 pandemic has dramatically changed our lives and habits. In just a few months, the most advanced and efficient health systems in the world have been overwhelmed by an infectious disease that has caused 3.26 million deaths and more than 156 million cases worldwide. Although the lung is the most frequently affected organ, the skin has also resulted in being a target body district, so much so as to suggest it may be a real "sentinel" of COVID-19 disease. Here we present 17 cases of skin manifestations studied and analyzed in recent months in our Department; immunohistochemical investigations were carried out on samples for the S1 spike-protein of SARS-CoV-2, as well as electron microscopy investigations showing evidence of virions within the constituent cells of the eccrine sweat glands and the endothelium of small blood vessels. Finally, we conduct a brief review of the COVID-related skin manifestations, confirmed by immunohistochemistry and/or electron microscopy, described in the literature