Effect of ocean acidification on growth and otolith condition of juvenile scup, Stenotomus chrysops

Increasing amounts of atmospheric carbon dioxide (CO2) from human industrial activities are causing changes in global ocean carbonate chemistry, resulting in a reduction in pH, a process termed "ocean acidification." It is important to determine which species are sensitive to elevated levels of CO2 because of potential impacts to ecosystems, marine resources, biodiversity, food webs, populations, and effects on economies. Previous studies with marine fish have documented that exposure to elevated levels of CO2 caused increased growth and larger otoliths in some species. This study was conducted to determine whether the elevated partial pressure of CO2 (pCO2) would have an effect on growth, otolith (ear bone) condition, survival, or the skeleton of juvenile scup, Stenotomus chrysops, a species that supports both important commercial and recreational fisheries. Elevated levels of pCO2 (1200-2600 µatm) had no statistically significant effect on growth, survival, or otolith condition after 8 weeks of rearing. Field data show that in Long Island Sound, where scup spawn, in situ levels of pCO2 are already at levels ranging from 689 to 1828 µatm due to primary productivity, microbial activity, and anthropogenic inputs. These results demonstrate that ocean acidification is not likely to cause adverse effects on the growth and survivability of every species of marine fish. X-ray analysis of the fish revealed a slightly higher incidence of hyperossification in the vertebrae of a few scup from the highest treatments compared to fish from the control treatments. Our results show that juvenile scup are tolerant to increases in seawater pCO2, possibly due to conditions this species encounters in their naturally variable environment and their well-developed pH control mechanisms.

Post Grado Internacional en Prevención de Riesgos Laborales y Salud Ocupacional. Experiencia de la Universidad de Alcalá en Venezuela

La gestión de la prevención de riesgos laborales (PRL) y de la salud ocupacional (SO) representa una tendencia creciente en la dinámica de las empresas del sector privado y público en América Latina y el Caribe (ALyC). La preservación de los niveles de seguridad y salud de los trabajadores se ha convertido en una variable que tiene influencia sobre el desempeño de las organizaciones y su responsabilidad social. El manejo asertivo de estas relaciones puede ser alcanzado si es planificado, ejecutado y controlado por personal directivo con una sólida formación técnica, gerencial y orientada a la innovación. En este sentido, en Venezuela se está desarrollando una experiencia de formación dirigida a personal directivo en esta área, la cual es ofrecida por la Universidad de Alcalá de Henares de España, a través de un novedoso modelo de estudios de Post Grado con títulos propios. El objetivo principal del modelo es conformar una comunidad del conocimiento, que sea capaz de investigar, desarrollar e innovar. En la actualidad, se han iniciado seis programas de Post Grado en los cuales interactúan docentes, investigadores, gerentes y profesionales del ramo, tantos españoles como latinoamericanos.

Alternative neural circuitry that might be impaired in the development of Alzheimer disease

It is well established that some individuals with normal cognitive capacity have abundant senile plaques in their brains. It has been proposed that those individuals are resilient or have compensation factors to prevent cognitive decline. In this comment, we explore an alternative mechanism through which cognitive capacity is maintained. This mechanism could involve the impairment of alternative neural circuitry. Also, the proportion of molecules such as A? or tau protein present in different areas of the brain could be important.