Search results for "Centro"

EctoparasiticArgulus coregoni(Crustacea: Branchiura) hedge their bets - studies on egg hatching dynamics

2004

Unpredictability in the temporal availability of susceptible hosts is likely to act as a selection pressure affecting the life history strategies of parasites. In highly variable environments the future of the lineage can be secured by spreading the risk, for example, by producing descendants that differ in their timing of emergence. Counter to this, in predictable environments a single “best-adapted” phenotype is expected. We asked whether ectoparasitic Argulus coregoni egg hatching pattern can be explained as a genetically canalized individual trait; an instance of phenotypic plasticity or bet-hedging. We collected egg clutches laid by individual A. coregoni females in early and late repr…

Maximum likelihood positioning for gamma-ray imaging detectors with depth of interaction measurement

2009

Abstract The center of gravity algorithm leads to strong artifacts for gamma-ray imaging detectors that are based on monolithic scintillation crystals and position sensitive photo-detectors. This is a consequence of using the centroids as position estimates. The fact that charge division circuits can also be used to compute the standard deviation of the scintillation light distribution opens a way out of this drawback. We studied the feasibility of maximum likelihood estimation for computing the true gamma-ray photo-conversion position from the centroids and the standard deviation of the light distribution. The method was evaluated on a test detector that consists of the position sensitive …

Parameter properties and stellar population of the old open cluster NGC 3960

2004

We present a $BVI$ photometric and astrometric catalogue of the open cluster NGC 3960, down to limiting magnitude $V\sim22$, obtained from observations taken with the Wide Field Imager camera at the MPG/ESO 2.2 m Telescope at La Silla. The photometry of all the stars detected in our field of view has been used to estimate a map of the strong differential reddening affecting this area. Our results indicate that, within the region where the cluster dominates, the $E(V-I)$ values range from 0.21 up to 0.78, with $E(V-I)=0.36$ ($E(B-V)=0.29$) at the nominal cluster centroid position; color excesses $E(V-I)$ up to 1 mag have been measured in the external regions of the field of view where field …

Noise fiber lasers

2021

In this paper, we present a brief review of the noise operation mode of fiber lasers. These lasers were studied recently by collaborative group that includes researchers, professors, and Ph.D. students from the Centro de Investigaciones en Optica, A.C. (Leon, Guanajuato, Mexico) and from the Universidad de Valencia (Valencia, Spain). Meanwhile, the pioneer works in this topic important for understanding the physics behind fiber lasers’ operation and for practical applications were done with the active participation of Dr. Evgeny Kuzin from the Instituto Nacional de Astrofisica, Optica y Electronica (Puebla, Mexico) and Dr. Georgina Beltrán-Pérez from the Benemérita Universidad Autónoma de P…

Cuando la izquierda quiere ser de centro

2002

Polar marine biology science in Portugal and Spain: Recent advances and future perspectives

2013

Xavier, José C. et al.

Cadmium stress effects indicating marine pollution in different species of sea urchin employed as environmental bioindicators

2019

In recent years, researches about the defense strategies induced by cadmium stress have greatly increased, invading several fields of scientific research. Mechanisms of cadmium-induced toxicity continue to be of interest for researchers given its ubiquitous nature and environmental distribution, where it often plays the role of pollutant for numerous organisms. The presence in the environment of this heavy metal has been constantly increasing because of its large employment in several industrial and agricultural activities. Cadmium does not have any biological role and, since it cannot be degraded by living organisms, it is irreversibly accumulated into cells, interacting with cellular comp…

Plan de Anualidad 2002

2002

En este documento se exponen los objetivos del Plan de Anualidad 2002 traducción práctica del contenido del borrador del segundo Plan del SIDA y de las directrices marcadas por el Plan Multisectorial 2001-2005 de la Secretaria del Plan Nacional sobre el Sida del Ministerio de Sanidad y Consumo Renovación del compromiso adquirido y herramienta de gestión durante este ejercicio para un mayor control de la epidemia en la Comunidad Valenciana. Los objetivos de este Plan se centran básicamente en la Pre¬vención de nuevas infecciones, la Reducción del impacto negativo personal y social de la epidemia y la Coordinación de esfuerzos contra VIH.

Prevención del Sida en la escuela : Pautas para la elaboración de un programa comportamental-educativo

2002

La prevención del sida en la adolescencia se ha convertido en la meta básica de los esfuerzos preventivos, debido a que la causa principal de los nuevos casos es precisa¬mente la transmisión sexual entre jóvenes y adolescentes. Esta situación ha provocado una gran demanda social de este tipo de intervenciones, Fundamentalmente en el ámbito escolar,En este trabajo se presentan una serie de directrices para el diseño e implantación de un programa de prevención del sida basado en un modelo comportamental-educativo que contempla las influencias paternas, de los compañeros y de los iguales, con el Fin de sustituir- los comportamientos de riesgo por conductas de promoción de la salud. Los objetiv…

Toxic effects induced by vanadium on sea urchin embryos

2020

Vanadium, a naturally occurring element widely distributed in soil, water and air, has received considerable interest because its compounds are often used in different applications, from industry to medicine. While the possible medical use of vanadium compounds is promising, its potential harmful effects on living organisms are still unclear. Here, for the first time, we provide a toxicological profile induced by vanadium on Paracentrotus lividus sea urchin embryos, reporting an integrated and comparative analysis of the detected effects reflecting vanadium-toxicity. At the morphological level we found a dose-dependent induction of altered phenotypes and of skeletal malformations. At the mo…