Las epistemologías críticas en la producción de conocimiento en Ciencia Política. Un estudio desde las trayectorias de docentes-investigadores de instituciones públicas

El presente proyecto pretendió aportar al estudio del desarrollo de la Ciencia Política en Argentina en el marco de la discusión iniciada por Giovanni Sartori, quien en el año 2004 cuestionó el status epistemológico- metodológico de la disciplina, dando inicio a una fructífera reflexión en torno a sus enfoques y paradigmas. En este marco, se sistematizaron y analizaron procesos de investigación concretos que, dentro del campo disciplinar, abrevan en diversas perspectivas epistemológicas críticas. Esto se llevó adelante a través de una serie de ejes de indagación orientados a analizar dichos procesos de modo transversal: 1- el reconocimiento de la posición del sujeto cognoscente como parte de la situación de investigación, 2- las articulaciones con sujetos y saberes extra-académicos en el proceso de construcción de conocimiento, 3- los vínculos con los espacios institucionales en los que se insertan las investigaciones y 4- las prácticas investigativas, académicas y pedagógicas concretas puestas en marcha en la producción de conocimiento. Estos ejes fueron abordados desde un enfoque cualitativo que combina el análisis documental de publicaciones científicas, con el análisis de trayectorias individuales y colectivas a través de entrevistas semiestructuradas a docentes investigadores de instituciones públicas.    ARK: http://id.caicyt.gov.ar/ark:/s22504559/n86d607b

Evaluation of Commercial Probiotic Products

Although there is a vast number of probiotic products commercially available due to their acceptability and increasing usage, their quality control has continuously been a major concern. This study aimed to assess some commercially available probiotics on the UK market for content in relation to their label claim. Seven products were used for the study. The bacteria content were isolated, identified and enumerated on selective media. The results revealed that all products evaluated contained viable probiotic bacteria but only three out of the seven products (43%) contained the claimed culture concentration or more. None of the multispecies product contained all the labelled probiotic bacteria. Misidentification of some species occurred. The results concurred with previous studies and showed that quality issues with commercial probiotics remain. Since probiotic activity is linked with probiotic concentration and is strain specific, the need exist for a global comprehensive legislation to control the quality of probiotics whose market is gaining huge momentum

A LuxS-Dependent Cell-to-Cell Language Regulates Social Behavior and Development in Bacillus subtilis

Cell-to-cell communication in bacteria is mediated by quorum-sensing systems (QSS) that produce chemical signal molecules called autoinducers (AI). In particular, LuxS/AI-2-dependent QSS has been proposed to act as a universal lexicon that mediates intra- and interspecific bacterial behavior. Here we report that the model organism Bacillus subtilis operates a luxS-dependent QSS that regulates its morphogenesis and social behavior. We demonstrated that B. subtilis luxS is a growth-phase-regulated gene that produces active AI-2 able to mediate the interspecific activation of light production in Vibrio harveyi. We demonstrated that in B. subtilis, luxS expression was under the control of a novel AI-2-dependent negative regulatory feedback loop that indicated an important role for AI-2 as a signaling molecule. Even though luxS did not affect spore development, AI-2 production was negatively regulated by the master regulatory proteins of pluricellular behavior, SinR and Spo0A. Interestingly, wild B. subtilis cells, from the undomesticated and probiotic B. subtilis natto strain, required the LuxS-dependent QSS to form robust and differentiated biofilms and also to swarm on solid surfaces. Furthermore, LuxS activity was required for the formation of sophisticated aerial colonies that behaved as giant fruiting bodies where AI-2 production and spore morphogenesis were spatially regulated at different sites of the developing colony. We proposed that LuxS/AI-2 constitutes a novel form of quorum-sensing regulation where AI-2 behaves as a morphogen-like molecule that coordinates the social and pluricellular behavior of B. subtilis

Mechanisms for thermal conduction in hydrogen hydrate

Extensive equilibrium molecular dynamics (MD) simulations have been performed to investigate thermal conduction mechanisms via the Green-Kubo approach for (type II) hydrogen hydrate, at 0.05 kbar and between 30 and 250 K, for both lightly-filled H2 hydrates (1s4l) and for more densely-filled H2 systems (2s4l), in which four H2 molecules are present in the large cavities, with respective single- and double-occupation of the small cages. The TIP4P water model was used in conjunction with a fully atomistic hydrogen potential along with long-range Ewald electrostatics. It was found that substantially less damping in guest-host energy transfer is present in hydrogen hydrate as is observed in common type I clathrates (e.g., methane hydrate), but more akin in to previous results for type II and H methane hydrate polymorphs. This gives rise to larger thermal conductivities relative to common type I hydrates, and also larger than type II and H methane hydrate polymorphs, and a more crystal-like temperature dependence of the thermal conductivity.Science Foundation IrelandOther funderIreland Canada University FoundationRoyal Irish Academyau, ti, ke, ab, is - TS 01/02/201