A time-dependent density functional theory scheme for efficient calculations of dynamic (hyper)polarizabilities

We present an efficient perturbative method to obtain both static and dynamic polarizabilities and hyperpolarizabilities of complex electronic systems. This approach is based on the solution of a frequency dependent Sternheimer equation, within the formalism of time-dependent density functional theory, and allows the calculation of the response both in resonance and out of resonance. Furthermore, the excellent scaling with the number of atoms opens the way to the investigation of response properties of very large molecular systems. To demonstrate the capabilities of this method, we implemented it in a real-space (basis-set free) code, and applied it to benchmark molecules, namely CO, H2O, and paranitroaniline (PNA). Our results are in agreement with experimental and previous theoretical studies, and fully validate our approach.Comment: 9 pages, 4 figure

Procedimiento de preparación, conservación, y uso en peces, del probiótico SHEWANELLA PUTREFACIENS PDP 11 para el control de enfermedades y la mejora en el crecimiento

Número de solicitud 201100385Procedimiento de preparación, conservación, y uso en peces, del probiótico Shewanella putresfaciens Pdp11 para el control de enfermedades y la mejora en el crecimiento. Preferentemente, el probiótico, compuesto por células enteras de la cepa Pdp11, se cultiva en TSAs durante 24 h a 22ºC. La preparación de una suspensión del probiótico, preferentemente sin proceso previo de liofilización o de inactivación física o química, se realiza mediante su incorporación en una matriz de alginato, preferentemente alginato sádico al 0,5%. La suspensión preparada se puede conservar sin pérdida significativa de viabilidad durante 20 - 30 días a 4ºC. Los productos alimenticios para peces son preparados mediante la adición en agitación de la suspensión de probiótico y, adicionalmente, CaCl2 50 mM, preferentemente mediante atomización.Universidad de Málaga (50%). Universidad de Almería (50%

Preparado de bacterias probióticas para su administración oral a peces cultivados basado en la encapsulación en hidrogeles de alginato

Número de solicitud: 201100469La invención consiste en un preparado para la administración oral del probiótico Shewanella PDP11 a peces. El preparado se caracteriza por contener células bacterianas viables de la cepa CECT 7627 encapsuladas en un hidrogel basado en alginato cálcico en forma de partículas esféricas de morfología uniforme y tamaño modificable para adaptarse a peces de distinto tamaño. Las cápsulas contienen aditivos organolépticos y/o nutricionales que actúan como atrayentes para los animales. El preparado mantiene viables a las bacterias durante periodos prolongados, es estable en medios acuáticos, y soporta el paso por el tubo digestivo de los peces, sobre los que ejerce efectos biológicos favorables. Su administración por vía oral es independiente del alimento habitual, evitando así la inactivación del microorganismo durante la fabricación del pienso.Universidad de Almerí

Cluster-surface and cluster-cluster interactions: Ab initio calculations and modeling of van der Waals forces

We present fully ab-initio calculations of van der Waals coefficients for two different situations: i) the interaction between hydrogenated silicon clusters; and ii) the interactions between these nanostructures and a non metallic surface (a silicon or a silicon carbide surface). The methods used are very efficient, and allow the calculation of systems containing hundreds of atoms. The results obtained are further analyzed and understood with the help of simple models. These models can be of interest for molecular dynamics simulations of silicon nanostructures on surfaces, where they can give a very fast yet sufficiently accurate determination of the van der Waals interaction at large separations.Comment: Phys. Rev.

ATUALIZAÇÃO EM DESMAME VENTILATÓRIO NO PÓS-OPERATÓRIO DE CIRURGIA CARDÍACA: A PRÁTICA DE ENFERMAGEM BASEDEADA EM EVIDÊNCIAS.

The present study integrates the line of Research Paradigms, Assistances Models and Knowing-Doing in Nursing. This study has the intention to present questions concerning to evidence-based practice of nursing inherent to ventilator weaning in the immediate postoperative of cardiac surgery. The evidences and debates of this study are results of nurses’ performance in a great university hospital, located in the city of Rio de Janeiro, in which were authorized to this professional the accomplishment of ventilator weaning, by means of institutional routine. In this manner, the present study has as objective to report the experience about the ventilator weaning carried through nurses in great hospital of Rio de Janeiro, subsidized by evidence-based practice. We have concluded for the pressing necessity of the elaboration of a protocol on national level concerning such practice.El actual estudio integra la línea de Investigación Paradigmas, de los Modelos Asistenciales y del Saber-Hacer en enfermería. Tiene la intención de presentar preguntas concernientes a la práctica de enfermería basada en la evidencia inherente a la desconexión de la ventilación en el postoperatorio inmediato de cirugía cardiaca. Las evidencias y discusiones de este estudio son fruto de la actuación de las enfermeras de un hospital universitario de gran porte, situado en la ciudad de Río de Janeiro, en el cual se facultó a estas profesionales la realización de la desconexión de la ventilación, por medio de rutina institucional. De esta manera, el actual estudio tiene el objetivo de relatar la experiencia referente a la desconexión de la ventilación realizada por enfermeros en un hospital de gran porte de Río de Janeiro, fundamentado en la práctica basada en evidencia. Concluimos con la necesidad urgente de la elaboración de un protocolo a nivel nacional referente a tal práctica.O presente estudo integra a linha de Pesquisa Paradigmas, Modelos Assistências e Saber-Fazer em Enfermagem. Este tem o propósito de apresentar questões concernentes à prática da enfermagem baseada em evidência inerentes ao desmame ventilatório no pós-operatório imediato de cirurgia cardíaca. As evidências e discussões deste estudo são frutos da atuação de enfermeiras de um hospital universitário de grande porte, localizado na cidade do Rio de Janeiro, no qual foi facultado a este profissional a realização do desmame ventilatório, mediante rotina institucional. Neste sentido, o presente estudo tem por objetivo relatar a experiência acerca do desmame ventilatório realizada por enfermeiros em hospital de grande porte do Rio de Janeiro, subsidiado pela prática baseada em evidência. Concluímos pela necessidade premente da elaboração de um protocolo a nível nacional acerca de tal prática

Real-space grids and the Octopus code as tools for the development of new simulation approaches for electronic systems

Real-space grids are a powerful alternative for the simulation of electronic systems. One of the main advantages of the approach is the flexibility and simplicity of working directly in real space where the different fields are discretized on a grid, combined with competitive numerical performance and great potential for parallelization. These properties constitute a great advantage at the time of implementing and testing new physical models. Based on our experience with the Octopus code, in this article we discuss how the real-space approach has allowed for the recent development of new ideas for the simulation of electronic systems. Among these applications are approaches to calculate response properties, modeling of photoemission, optimal control of quantum systems, simulation of plasmonic systems, and the exact solution of the Schrödinger equation for low-dimensionality systems

Follow-up study on lead exposure in children living in a smelter community in northern Mexico

<p>Abstract</p> <p>Background</p> <p>To study the changes of children lead exposure in the city of Torreon during the last five years, after environmental and public health interventions, using the timeline of lead in blood concentration as the biomarker of exposure and its relation to lead in soil concentrations.</p> <p>Methods</p> <p>This follow-up study started in 2001 and consisted of 232 children living in nine neighborhoods in Torreon. Children were tested at 0, 6, 12 and 60 months. Lead in blood concentrations, Hemoglobin, Zinc-Protoporphyrin, anthropometric measures and socioeconomic status questionnaire was supplied to the parents.</p> <p>Results</p> <p>Median and range of lead in blood concentrations obtained at 0, 6, 12, 60 months were: 10.12 μg/dl (1.9 - 43.8), 8.75 μg/dl (1.85 - 41.45), 8.4 μg/dl (1.7 - 35.8) and 4.4 μg/dl (1.3 - 30.3), respectively. The decrease of lead in blood levels was significantly related to ages 0, 6, 12 and 60 months of the follow-up study. The timeline of B-Pb was associated with the timeline of lead in soil concentrations.</p> <p>Conclusions</p> <p>B-Pb levels have significantly decreased in the group of children studied. This could be explained by a) environmental interventions by authorities and the smelter companies, b) normal changes in hygienic habits as children age and c) lead redistribution from blood to hard tissues.</p

Functional coupling of TRPV4 cationic channel and large conductance, calcium-dependent potassium channel in human bronchial epithelial cell lines

Abstract Calcium-dependent potassium channels are implicated in electrolyte transport, cell volume regulation and mechanical responses in epithelia, although the pathways for calcium entry and their coupling to the activation of potassium channels are not fully understood. We now show molecular evidence for the presence of TRPV4, a calcium permeable channel sensitive to osmotic and mechanical stress, and its functional coupling to the large conductance calciumdependent potassium channel (BK Ca ) in a human bronchial epithelial cell line (HBE). Reverse transcriptase polymerase chain reaction, intracellular calcium imaging and whole-cell patch-clamp experiments using HBE cells demonstrated the presence of TRPV4 messenger and Ca 2+ entry, and outwardly rectifying cationic currents elicited by the TRPV4 specific activator 4α-phorbol 12,13-didecanoate (4αPDD). Cell-attached and whole-cell patch-clamp of HBE cells exposed to 4αPDD, and hypotonic and high-viscosity solutions (related to mechanical stress) revealed the activation of BK Ca channels subsequent to extracellular Ca 2+ influx via TRPV4, an effect lost upon antisense-mediated knock-down of TRPV4. Further analysis of BK Ca modulation after TRPV4 activation showed that the Ca 2+ signal can be generated away from the BK Ca location at the plasma membrane, and it is not mediated by intracellular Ca 2+ release via ryanodine receptors. Finally, we have shown that, unlike the reported disengagement of TRPV4 and BK Ca in response to hypotonic solutions, cystic fibrosis bronchial epithelial cells (CFBE) preserve the functional coupling of TRPV4 and BK Ca in response to high-viscous solutions

Octopus, a computational framework for exploring light-driven phenomena and quantum dynamics in extended and finite systems

Over the last few years, extraordinary advances in experimental and theoretical tools have allowed us to monitor and control matter at short time and atomic scales with a high degree of precision. An appealing and challenging route toward engineering materials with tailored properties is to find ways to design or selectively manipulate materials, especially at the quantum level. To this end, having a state-of-the-art ab initio computer simulation tool that enables a reliable and accurate simulation of light-induced changes in the physical and chemical properties of complex systems is of utmost importance. The first principles real-space-based Octopus project was born with that idea in mind, i.e., to provide a unique framework that allows us to describe non-equilibrium phenomena in molecular complexes, low dimensional materials, and extended systems by accounting for electronic, ionic, and photon quantum mechanical effects within a generalized time-dependent density functional theory. This article aims to present the new features that have been implemented over the last few years, including technical developments related to performance and massive parallelism. We also describe the major theoretical developments to address ultrafast light-driven processes, such as the new theoretical framework of quantum electrodynamics density-functional formalism for the description of novel light-matter hybrid states. Those advances, and others being released soon as part of the Octopus package, will allow the scientific community to simulate and characterize spatial and time-resolved spectroscopies, ultrafast phenomena in molecules and materials, and new emergent states of matter (quantum electrodynamical-materials)