Search results for "Ciencias Naturales"
showing 7 items of 287 documents
A Co36Cluster Assembled from the Reaction of Cobalt Pivalate with 2,3-Dicarboxypyrazine
2009
A record Co36 cluster is prepared. This mixed-valent compound containing CoII and CoIII centers is formed in the reaction of a dinuclear cobalt pivalate species with the polydentate 2,3-dicarboxypyrazine ligand. In terms of magnetic properties it behaves as a {Co16-Co16} supramolecular dimer in which the S = A spin ground states of each monomer do not interact. Fil: Alborés, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, M…
Synthesis and biological evaluation of sphingosine kinase 2 inhibitors with anti-inflammatory activity.
2019
The synthesis of inhibitors of SphK2 with novel structural scaffolds is reported. These compounds were designed from a molecular modeling study, in which the molecular interactions stabilizing the different complexes were taken into account. Particularly interesting is that 7‐bromo‐2‐(2‐phenylethyl)‐2,3,4,5‐tetrahydro‐1,4‐epoxynaphtho[1,2‐b]azepine, which is a selective inhibitor of SphK2, does not exert any cytotoxic effects and has a potent anti‐inflammatory effect. It was found to inhibit mononuclear cell adhesion to the dysfunctional endothelium with minimal impact on neutrophil–endothelial cell interactions. The information obtained from our theoretical and experimental study can be us…
Predicted gamma-ray image of SN 1006 due to inverse Compton emission
2009
We propose a method to synthesize the inverse Compton (IC) gamma-ray image of a supernova remnant starting from the radio (or hard X-ray) map and using results of the spatially resolved X-ray spectral analysis. The method is successfully applied to SN 1006. We found that synthesized IC gamma-ray images of SN 1006 show morphology in nice agreement with that reported by the H.E.S.S. collaboration. The good correlation found between the observed very-high energy gamma-ray and X-ray/radio appearance can be considered as an evidence that the gamma-ray emission of SN 1006 observed by H.E.S.S. is leptonic in origin, though the hadronic origin may not be excluded.
Search for photonic signatures of gauge-mediated supersymmetry in 8TeV pp collisions with the ATLAS detector
2015
A search is presented for photonic signatures motivated by generalized models of gauge-mediated supersymmetry breaking. This search makes use of 20.3 fb[superscript −1] of proton-proton collision data at √s = 8 TeV recorded by the ATLAS detector at the LHC, and explores models dominated by both strong and electroweak production of supersymmetric partner states. Four experimental signatures incorporating an isolated photon and significant missing transverse momentum are explored. These signatures include events with an additional photon, lepton, b-quark jet, or jet activity not associated with any specific underlying quark flavor. No significant excess of events is observed above the Stand…
Ultra-High Energy Neutrinos at the Pierre Auger Observatory
2013
The observation of ultrahigh energy neutrinos (UHE nu s) has become a priority in experimental astroparticle physics. UHE nu s can be detected with a variety of techniques. In particular, neutrinos can interact in the atmosphere (downward-going nu) or in the Earth crust (Earth-skimming nu), producing air showers that can be observed with arrays of detectors at the ground. With the surface detector array of the Pierre Auger Observatory we can detect these types of cascades. The distinguishing signature for neutrino events is the presence of very inclined showers produced close to the ground (i.e., after having traversed a large amount of atmosphere). In this work we review the procedure and …
Factors affecting the production of putrescine from agmatine by Lactobacillus hilgardii X1B isolated from wine
2008
Aims: To elucidate and characterize the metabolic putrescine synthesis pathway from agmatine by Lactobacillus hilgardii X1B. Methods and Results: The putrescine formation from agmatine by resting cells (the normal physiological state in wine) of lactic acid bacteria isolated from wine has been determined for the first time. Agmatine deiminase and N-carbamoylputrescine hydrolase enzymes, determined by HPLC and LC-Ion Trap Mass Spectrometry, carried out the putrescine synthesis from agmatine. The influence of pH, temperature, organic acids, amino acids, sugars and ethanol on the putrescine formation in wine was determined. Conclusions: Resting cells of Lact. hilgardii X 1B produce putrescine …
Search for the Decay of the Higgs Boson to Charm Quarks with the ATLAS Experiment
2018
A direct search for the standard model Higgs boson decaying to a pair of charm quarks is presented. Associated production of the Higgs and Z bosons, in the decay mode ZH→ℓ+ℓ−c¯c is studied. A data set with an integrated luminosity of 36.1 fb−1 of pp collisions at √s=13TeV recorded by the ATLAS experiment at the LHC is used. The H→c¯c signature is identified using charm-tagging algorithms. The observed (expected) upper limit on σ(pp→ZH)×B(H→c¯c) is 2.7 (3.9+2.1−1.1) pb at the 95% confidence level for a Higgs boson mass of 125 GeV, while the standard model value is 26 fb.