Observations of coastal upwelling off Uruguay downshelf of the Plata estuary, South America

We analyze hydrographic and current observations of an upwelling center off eastern South America on the Uruguayan coast (∼35S) and downshelf from the Rio de la Plata estuary. Our observations show that the buoyancy-driven subtidal alongshore circulation is modulated by winds. During the winter, strong upwelling-favorable local winds forced the Rio de la Plata buoyant plume poleward. In the summer, the plume detached from the coast with warm and saline subtropical waters intruding from the north. These waters bounded the upwelling of cold waters in the nearshore area off Uruguay. A shallow submarine canyon cutting obliquely across the shelf facilitates the advection of cold waters into the coastal upwelling domain. An upwelling jet was detected off Uruguay for summer conditions, while for winter the plume configuration generated strong horizontal shear of along-shelf currents. Cross-shelf circulation was dependent on the coastal stratification. Under low stratification (summer) a two-layer circulation developed, with thick surface and bottom mixed layers flowing in opposite directions. High stratification levels (winter) modified this pattern by allowing circulation along a thick stratified interior. The existence of upwelling was linked to the history of wind events and shelf stratification. During the winter, downwelling winds frequently restore the plume, so the upwelling efficiency is very low. In the summer, downwelling events are less frequent and intense, so that the cumulative effect of upwelling events act to export the Plata freshwaters offshore. The reduction of inner-shelf stratification increases the likelihood of a full upwelling to the surface. Analysis of the wind-induced Ekman transport suggests that the Uruguay upwelling system reflects a seasonal wind pattern modulated by significant interannual variability

Lobotomia pré-frontal. Resultados clínicos em hospital privado

Escola Paulista de Medicina Instituto Paulista Serviço de PsiquiatriaHospital de JuqueriSecção de Higiene Mental Escolar Serviço de Neuro-Psiquiatria do Instituto PaulistaUNIFESP, EPM, Instituto Paulista Serviço de PsiquiatriaSciEL

Basal-plane Incommensurate Phases in HCP Structures

An Ising model with competing interaction is used to study the appearance of incommensurate phases in the basal plane of an hexagonal closed-packed structure. The calculated mean-field phase diagram reveals various 1q-incommensurate and lock-in phases. The results are applied to explain the basal-plane incommensurate phase in some compounds of the A'A"BX_4 family, like K_2MoO_4, K_2WO_4, Rb_2WO4 and to describe the sequence of high-temperature phase transitions in other compounds of this family.Comment: 8 pages, RevTeX + 4 ps figure

Experimental observation of fractional topological phases with photonic qudits

Geometrical and topological phases play a fundamental role in quantum theory. Geometric phases have been proposed as a tool for implementing unitary gates for quantum computation. A fractional topological phase has been recently discovered for bipartite systems. The dimension of the Hilbert space determines the topological phase of entangled qudits under local unitary operations. Here we investigate fractional topological phases acquired by photonic entangled qudits. Photon pairs prepared as spatial qudits are operated inside a Sagnac interferometer and the two-photon interference pattern reveals the topological phase as fringes shifts when local operations are performed. Dimensions $d = 2, 3$ and $4$ were tested, showing the expected theoretical values.Comment: 6 pages, 4 figure

Résultats électroencéphalographiques dans 33 cas de tumeurs intracraniennes chirurgicalement vérififes

Escola Paulista de MedicinaUniv. de São Paulo Fac. Med.Instituto de Electrencefalografia (São Paulo)Escola Paulista de Medicina Serviço de NeurologiaUNIFESP, EPM, Serviço de NeurologiaSciEL

Utilização de carvão e subprodutos da carbonização vegetal na agricultura: aprendendo com as Terras Pretas de Índio.

A Carbonização Vegetal. Físico química da carbonização vegetal. Características e propriedades do carvão e de subprodutos da carbonização vegetal. Carvão. Alcatrão vegetal. Ácido pirolenhoso. A produção de carvão vegetal e subprodutos da carbonização vegetal no Brasil. Potencial produção de fertilizantes e condicionadores de solos a partir de carvão e subprodutos da carbonização vegetal. Síntese de ácidos húmicos a partir de carvão vegetal. Utilização de carvão na produção de fertilizantes orgânicos e substratos. Produção de condicionadores orgânicos. Utilização de fino de carvão como substrato para mudas. Próximos passos para a pesquisa, desenvolvimento e inovação

The Yang-Baxter equation for PT invariant nineteen vertex models

We study the solutions of the Yang-Baxter equation associated to nineteen vertex models invariant by the parity-time symmetry from the perspective of algebraic geometry. We determine the form of the algebraic curves constraining the respective Boltzmann weights and found that they possess a universal structure. This allows us to classify the integrable manifolds in four different families reproducing three known models besides uncovering a novel nineteen vertex model in a unified way. The introduction of the spectral parameter on the weights is made via the parameterization of the fundamental algebraic curve which is a conic. The diagonalization of the transfer matrix of the new vertex model and its thermodynamic limit properties are discussed. We point out a connection between the form of the main curve and the nature of the excitations of the corresponding spin-1 chains.Comment: 43 pages, 6 figures and 5 table