Time filter

Source Type

Comodoro Rivadavia, Argentina

Bodanza G.A.,CONICET | Alessio C.A.,Catholic University of Cuyo
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

An argument is reinstated when all its defeaters are in turn ultimately defeated. This is a kind of principle governing most argument systems in AI. Nevertheless, some criticisms to this principle have been offered in the literature. Assuming that reinstatement is prima facie acceptable, we analyze some counterexamples in order to identify common causes. As a result, we found that the problem arises when arguments in a chain of attacks are related by specificity. We argue that the reason is that non-maximally specific arguments can be reinstated originating fallacious justifications. Following old intuitions by Carl Hempel about inductive explanations, we propose a requirement of maximal specificity on defeasible arguments and introduce "undermining defeaters" which, in essence, facilitate the rejection of those arguments which do not satisfy the requirement. This ideas are formally defined using the DeLP system for defeasible logic programming. © 2014 Springer-Verlag.

Bruno M.A.,McGill University | Bruno M.A.,Catholic University of Cuyo | Cuello A.C.,McGill University
Neurobiology of Aging | Year: 2012

Basal forebrain cholinergic neurons (BFCN), a system involved in learning and memory processes, are highly dependent on a continuous supply of biologically active nerve growth factor (NGF). Age-related cholinergic atrophy and cell loss in normal brains is apparently not complemented by reductions in the levels of NGF as could be expected. In the present work, cortical proNGF/NGF were immunoprecipitated from cortical brain homogenates from young and aged and behaviorally characterized rats and resolved with antinitrotyrosine antibodies to reveal nitration of tyrosine residues in proteins. Cortical proNGF in aged and cognitively impaired rats was found to be a target for peroxynitrite-mediated oxidative damage with correlative impact on decrease in choline acetyltransferase activity. These studies provide evidence for oxidative stress damage of NGF molecules in the cerebral cortex of cognitively impaired aged rats as previously shown in AD human brains. © 2012 Elsevier Inc.

Kruse M.S.,CONICET | Vega M.C.,CONICET | Rey M.,CONICET | Coirini H.,CONICET | And 2 more authors.
Journal of Endocrinology | Year: 2014

Gestational diabetes (GD) alters normal fetal development and is related to a diabetogenic effect in the progeny. Liver X receptors (LXRs) are considered to be potential drug targets for the regulation, treatment, or prevention of diabetes. The aim of this study was to evaluate early and late changes of LXR in the hippocampus and hypothalamus of the male and female offspring of control (CO) and diabetic (DO) mothers. We used an experimental model of streptozotocin-induced GD to assess the protein expression of LXRα (NR1H3) and LXRβ (NR1H2) by western blotting. The tissues were obtained from CO and DO animals at postnatal day 1 (1D), day 10 (10D), and day 35 (35D) and 9 months (9M). In CO, the LXR expression showed significant differences among the groups, which were tissue- and receptor-specific (P<0.05). Sex differences in CO were found only in the hypothalamus for LXRβ expression at 35D and 9M (P<0.05). When CO and DO were compared, differences between them were observed in the majority of the studied groups at 1D (male hippocampus, LXRα 31%and LXRβ 161%; female hippocampus, LXRβ 165%; male hypothalamus, LXRβ 182%; and female hypothalamus, LXRα 85%; P<0.05). However, these differences disappeared later with the exception of LXRβ expression in the male hypothalamus (P<0.05). The area under the curve during the glucose tolerance test correlated negatively with LXRβ in CO but not in DO animals. Moreover, in a male DO subpopulation this correlation was positive as it occurs in intolerant animals. These results indicate that GD affects hypothalamic LXR expression differently inmale and female offspring. © 2014 Society for Endocrinology.

Romero-Cano R.,Jaume I University | Kassuha D.,Catholic University of Cuyo | Peris-Vicente J.,Jaume I University | Roca-Genoves P.,Jaume I University | And 2 more authors.
Analyst | Year: 2015

A micellar liquid chromatographic method has been developed for the simultaneous quantification of the pesticides thiabendazole and chlorpyrifos, as well as an alkylphenol, which is included in pesticide formulations, i.e., 4-tert-octylphenol, in water. A sample was filtered and directly injected, avoiding large extraction steps using toxic solvents, thus expediting the experimental procedure. The contaminants were eluted without interferences in <17 min, using a mobile phase of 0.15 M sodium dodecyl sulfate-6% 1-pentanol buffered at pH 3, running through a C18 column at 1 mL min-1 under the isocratic mode. This optimal mobile phase was selected using a statistical approach, which considers the retention factor, efficiency and peak shape of the analytes measured in only a few mobile phases. The detection was carried out by measuring absorbance at 220 nm. The method was successfully validated in terms of specificity, calibration range (0.5-10 mg L-1), linearity (r2 > 0.994), limit of detection and quantification (0.2-0.3; and 0.5-0.8 mg L-1, respectively), intra- and interday accuracy (95.2-102.9%), precision (<8.3%), and ruggedness (<9.3%). The stability in storage conditions (at least 14 days) was studied. The method was safe, inexpensive, produced little pollutant and has a short analysis time, thus it is useful for the routine analysis of samples. Finally, the method was applied to analyse wastewater from the fruit-processing industry, wastewater treatment plants, and in sewage water belonging to the Castelló area (Spain). The results were similar to those obtained by an already reliable method. This journal is © The Royal Society of Chemistry.

Garcia J.J.,Catholic University of Cuyo
Cuadernos de bioética : revista oficial de la Asociación Española de Bioética y Ética Médica | Year: 2013

Bioethics is a rapidly growing discipline. It needs clear philosophical and theological foundations to remain a sure guide in promoting and defending the gift of life. In this paper it is not our task to perform a detailed analysis about the rich tenets of personalist bioethics. Instead, we make a comparative table between two bioethical models or proposals, Principialism and Personalism, similar in some respects, but different in others. So, the criteria that will guide us in deciding on biomedical practice will become clearer.

Discover hidden collaborations