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Montevideo, Uruguay

"University of the Republic" redirects here. For the university in San Marino, see University of the Republic of San Marino.The University of the Republic is Uruguay's public university. It is the most important, oldest, and largest university of the country, with a student body 108.886 students . It was founded on July 18, 1849 in Montevideo, where most of its buildings and facilities are still located. Its current Rector is Dr. Roberto Markarián. Wikipedia.

University of the Republic of Uruguay and Consejp Superior De Investigaciones Cientificas Cisic | Date: 2010-01-26

Compounds derived from imidazo[4,5-c][1,2,6]thiadiazine 2,2-dioxides, for use as a drug or pharmaceutical composition for treatment of parasitic diseases, preferably of diseases caused by parasites of the

Rodriguez De Sensale G.,University of the Republic of Uruguay
Cement and Concrete Composites | Year: 2010

In this paper the effects of partial replacements of Portland cement by rice-husk ash (RHA) on the durability of conventional and high performance cementitious materials are investigated. Different percentages of RHA replacement levels, two RHAs (amorphous and partially crystalline optimized by dry-milling) and several water-cementitious materials ratio are studied. The following durability aspects were tested: air permeability, chloride ion penetration, alkali-silica expansion, sulfate and acid resistance. The results were compared with those of cementitious materials without RHA. It is concluded from the tested properties that the incorporation of both RHAs in concretes show different behaviors for air permeability and chloride ion penetration depending on the water/cementitious materials ratio used; in mortars, it reduces the mass loss of specimens exposed to hydrochloric acid solution and decreases the expansion due to sulfate attack and the alkali-silica reaction. The results of durability aspects due to physical or pozzolanic effects after the addition of both RHAs, and its chemical composition, in general indicate an enhanced performance, proving the feasibility of its rational utilization as a supplementary cementing material. © 2010 Elsevier Ltd. All rights reserved. Source

Romanelli A.,University of the Republic of Uruguay
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

A thermodynamic theory is developed to describe the behavior of the entanglement between the coin and position degrees of freedom of the quantum walk on the line. It is shown that, in spite of the unitary evolution, a steady state is established after a Markovian transient stage. This study suggests that if a quantum dynamics develops in a composite Hilbert space (i.e., the tensor product of several subspaces), then the behavior of an operator that belongs only to one of the subspaces may camouflage the unitary character of the global evolution. © 2012 American Physical Society. Source

Radi R.,University of the Republic of Uruguay
Accounts of Chemical Research | Year: 2013

In proteins, the nitration of tyrosine residues to 3-nitro-tyrosine represents an oxidative post-translational modification that disrupts nitric oxide (•NO) signaling and skews metabolism towards pro-oxidant processes. Indeed, excess levels of reactive oxygen species in the presence of •NO or •NO-derived metabolites lead to the formation of nitrating species such as peroxynitrite. Thus, protein 3-nitrotyrosine has been established as a biomarker of cell, tissue, and systemic "nitroxidative stress". Moreover, tyrosine nitration modifies key properties of the amino acid: phenol group pKa, redox potential, hydrophobicity, and volume. Thus, the incorporation of a nitro group (-NO 2) into protein tyrosines can lead to profound structural and functional changes, some of which contribute to altered cell and tissue homeostasis.In this Account, I describe our current efforts to define (1) biologically-relevant mechanisms of protein tyrosine nitration and (2) how this modification can cause changes in protein structure and function at the molecular level. First, I underscore the relevance of protein tyrosine nitration via free-radical-mediated reactions (in both peroxynitrite-dependent and -independent pathways) involving a tyrosyl radical intermediate (Tyr •). This feature of the nitration process is critical because Tyr• can follow various fates, including the formation of 3-nitrotyrosine. Fast kinetic techniques, electron paramagnetic resonance (EPR) studies, bioanalytical methods, and kinetic simulations have all assisted in characterizing and fingerprinting the reactions of tyrosine with peroxynitrite and one-electron oxidants and its further evolution to 3-nitrotyrosine. Recent findings show that nitration of tyrosines in proteins associated with biomembranes is linked to the lipid peroxidation process via a connecting reaction that involves the one-electron oxidation of tyrosine by lipid peroxyl radicals (LOO•).Second, immunochemical and proteomic-based studies indicate that protein tyrosine nitration is a selective process in vitro and in vivo, preferentially directed to a subset of proteins, and within those proteins, typically one or two tyrosine residues are site-specifically modified. The nature and site(s) of formation of the proximal oxidizing or nitrating species, the physicochemical characteristics of the local microenvironment, and the structural features of the protein account for part of this selectivity. How this relatively subtle chemical modification in one tyrosine residue can sometimes cause dramatic changes in protein activity has remained elusive. Herein, I analyze recent structural biology data of two pure and homogenously nitrated mitochondrial proteins (i.e., cytochrome c and manganese superoxide dismutase, MnSOD) to illustrate regioselectivity and structural effects of tyrosine nitration and subsequent impact in protein loss- or even gain-of-function. © 2012 American Chemical Society. Source

Naya D.E.,University of the Republic of Uruguay
Proceedings. Biological sciences / The Royal Society | Year: 2013

Thermal conductance measures the ease with which heat leaves or enters an organism's body. Although the analysis of this physiological variable in relation to climatic and ecological factors can be traced to studies by Scholander and colleagues, only small advances have occurred ever since. Here, we analyse the relationship between minimal thermal conductance estimated during summer (Cmin) and several ecological, climatic and geographical factors for 127 rodent species, in order to identify the exogenous factors that have potentially affected the evolution of thermal conductance. In addition, we evaluate whether there is compensation between Cmin and basal metabolic rate (BMR)-in such a way that a scale-invariant ratio between both variables is equal to one-as could be expected from the Scholander-Irving model of heat transfer. Our major findings are (i) annual mean temperature is the best single predictor of mass-independent Cmin. (ii) After controlling for the effect of body mass, there is a strong positive correlation between log10 (Cmin) and log10 (BMR). Further, the slope of this correlation is close to one, indicating an almost perfect compensation between both physiological variables. (iii) Structural equation modelling indicated that Cmin values are adjusted to BMR values and not the other way around. Thus, our results strongly suggest that BMR and thermal conductance integrate a coordinated system for heat regulation in endothermic animals and that summer conductance values are adjusted (in an evolutionary sense) to track changes in BMRs. Source

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