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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.

Barreiro M.,University of the Republic of Uruguay
Climate Dynamics | Year: 2010

We perform a systematic study of the predictability of surface air temperature and precipitation in Southeastern South America (SESA) using ensembles of AGCM simulations, focusing on the role of the South Atlantic and its interaction with the El Niño-Southern Oscillation (ENSO). It is found that the interannual predictability of climate over SESA is strongly tied to ENSO showing high predictability during the seasons and periods when there is ENSO influence. The most robust ENSO signal during the whole period of study (1949-2006) is during spring when warm events tend to increase the precipitation over Southeastern South America. Moreover, the predictability shows large inter-decadal changes: for the period 1949-1977, the surface temperature shows high predictability during late fall and early winter. On the other hand, for the period 1978-2006, the temperature shows (low) predictability only during winter, while the precipitation shows not only high predictability in spring but also in fall. Furthermore, it is found that the Atlantic does not directly affect the climate over SESA. However, the experiments where air-sea coupling is allowed in the south Atlantic suggest that this ocean can act as a moderator of the ENSO influence. During warm ENSO events the ocean off Brazil and Uruguay tends to warm up through changes in the atmospheric heat fluxes, altering the atmospheric anomalies and the predictability of climate over SESA. The main effect of the air-sea coupling is to strengthen the surface temperature anomalies over SESA; changes in precipitation are more subtle. We further found that the thermodynamic coupling can increase or decrease the predictability. For example, the air-sea coupling significantly increases the skill of the model in simulating the surface air temperature anomalies for most seasons during period 1949-1977, but tends to decrease the skill in late fall during period 1978-2006. This decrease in skill during late fall in 1978-2006 is found to be due to a wrong simulation of the remote ENSO signal that is further intensified by the local air-sea coupling in the south Atlantic. Thus, our results suggest that climate models used for seasonal prediction should simulate correctly not only the remote ENSO signal, but also the local air-sea thermodynamic coupling. © 2009 Springer-Verlag.

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.

Radi R.,University of the Republic of Uruguay
Journal of Biological Chemistry | Year: 2013

Peroxynitrite is the product of the diffusion-controlled reaction of nitric oxide and superoxide radicals. Peroxynitrite, a reactive short-lived peroxide with a pKa of 6.8, is a good oxidant and nucleophile. It also yields secondary free radical intermediates such as nitrogen dioxide and carbonate radicals. Much of nitric oxide- and superoxide-dependent cytotoxicity resides on peroxynitrite, which affects mitochondrial function and triggers cell death via oxidation and nitration reactions. Peroxynitrite is an endogenous toxicant but is also a cytotoxic effector against invading pathogens. The biological chemistry of peroxynitrite is modulated by endogenous antioxidant mechanisms and neutralized by synthetic compounds with peroxynitrite-scavenging capacity. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.

The influence of antimalarials on lipids in systemic lupus erythematosus (SLE) has been identified in several studies but not in many prospective cohorts. The aim of this study was to longitudinally determine the effect of antimalarials on the lipoprotein profile in SLE. Patients and methods: Fasting total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL) and low-density lipoprotein cholesterol (LDL) plasma levels were determined at entry and after 3 months of hydroxychloroquine (HCQ) treatment in a longitudinal evaluation of 24 patients with SLE. Results: a significant decrease in TC (198 ± 33.7 vs. 183 ± 30.3 mg/dl, p = 0.023) and LDL levels (117 ± 31.3 vs. 101 ± 26.2 mg/dl, p = 0.023) were detected after the 3 months of HCQ therapy. The reduction of 7.6% in TC (p = 0.055) and 13.7% in LDL levels (p = 0.036) determined a significant decrease in the frequency of dyslipidemia (26% vs. 12.5%, p = 0.013) after HCQ therapy. Conclusion: This longitudinal study demonstrated the beneficial effect of antimalarials on lipids in SLE since this therapy induced a reduction of atherogenic lipoproteins.

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.

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