Fundación Instituto Leloir

About: Fundación Instituto Leloir is a facility organization based out in Buenos Aires, Argentina. It is known for research contribution in the topics: Dentate gyrus & Neurogenesis. The organization has 702 authors who have published 1052 publications receiving 39299 citations.

Spatial patterns of conditions leading to peak O3 concentrations revealed by clustering analysis of modeled data

Abstract: Air quality models are currently the best available tool to estimate ozone (O3) concentrations in the Metropolitan Area of Buenos Aires (MABA). While the DAUMOD-GRS has been satisfactorily evaluated against observations in the urban area, a Monte Carlo (MC) analysis showed that it is the region around the MABA, where the lack of observations impedes model testing, that concentrates not only the greatest estimated O3 peak levels but also the largest model uncertainty. In this work, we apply clustering analysis to these MC outcomes in order to study the spatial patterns of conditions leading to peak ozone hourly concentrations. Results show that families of conditions distribute, as emissions, radially around the city. A cluster exhibiting an O3 morning peak dominates in low-emission areas, a behavior that can be explained both from theory and from the few monitoring campaigns carried out in the city. Its distinct dynamics compared with the typical O3 diurnal profile occurring in the urban area suggests the need of new ozone measurements in the surroundings of the MABA which could contribute to improve our understanding of O3 formation drivers in this region. The results illustrate the potential of applying clustering analysis on large ensembles of modeled data to better understand the variability in model solutions.

Isolated DNA fragment of the SPARC human promoter and its use for driving the expression of an heterologous gene in tumor cells

Abstract: An isolated DNA sequence corresponding to a region of the SPARC gene human promoter from base pair −513 to base pair +35 capable of driving the expression of a heterologous gene of interest, that can be associated to any other promoter sequence, such as radiation responsive sequence, hypoxia responsive sequence and free-radical responsive sequence The invention also provides constructs and DNA recombinant expression viral vectors, comprising the isolated sequence of the SPARC gene human promoter and at least one heterologous gene operably linked thereto, wherein the promoter sequence drives the expression of the at least one heterologous gene in tumor cells Pharmaceutical compositions and a method for treating tumors are also provided

Neighbor signals perceived by phytochrome B increase thermotolerance in Arabidopsis

Abstract: Due to the preeminence of reductionist approaches, our understanding of plant responses to combined stresses is limited We speculated that light-quality signals of neighboring vegetation might increase susceptibility to heat shocks because shade reduces tissue temperature and hence the likeness of heat shocks In contrast, plants of Arabidopsis thaliana grown under low red / far-red ratios typical of shade were less damaged by heat stress than plants grown under simulated sunlight Shade reduces the activity of phytochrome B (phyB) and the phyB mutant showed high tolerance to heat stress even under simulated sunlight The enhanced heat tolerance under low red / far-red ratios failed in a multiple mutant of PHYTOCHROME INTERACTING FACTORs The phyB mutant showed reduced expression of several fatty acid desaturase (FAD) genes, proportion of fully unsaturated fatty acids and electrolyte leakage of membranes exposed to a heat shock Activation of phyB by red light also reduced thermotolerance of dark-grown (etiolated) seedlings but not via changes in FAD gene expression and membrane stability We propose that the reduced photosynthetic capacity linked to thermotolerant membranes would be less costly under shade, where the light input itself limits photosynthesis