10,508 research outputs found
The Higgs decay rate to two photons in a model with two fermiophobic-Higgs doublets
We consider a three Higgs doublet model with an symmetry in which
beside the SM-like doublet there are two fermiophobic doublets. Due to the new
charged scalars there is an enhancement in the two-photon decay while the other
channels have the same decay widths that the SM neutral Higgs. The fermiophobic
scalars are mass degenerated unless soft terms breaking the symmetry are
added.Comment: typos were corrected, the figures have been modified and the
conclusions were increased. Still contains 15 pages, 2 figure
The effect of the alkali metal cation on the electrocatalytic oxidation of formate on platinum
Non-covalent interactions between hydrated alkali metal cations and adsorbed oxygenated species on platinum might considerably inhibit some electrocatalytic reactions. We report in this communication the effect exerted by electrolyte alkali metal cations on the electro-oxidation of formate ions on platinum. The system was investigated by means of cyclic voltammetry and chronoamperometry in the presence of an electrolyte containing Li+, Na+, or K+. As already observed for other systems, the general activity towards the electro-oxidation of formate ions was found to increase in the sequence Li+ + +. In addition, we observed that the inhibition caused by smaller cations has a peculiar potential dependence because of the multi-peaked current profile of the electro-oxidation of formate on platinum. In this respect, we have also identified a new effect caused by cation inhibition at intermediate potentials, namely a peak splitting towards the use of smaller cations. Results are discussed in connection with mechanistic aspects of this model system
A construção de saberes sobre a Área de Reserva Legal em assentamento rural.
Este artigo apresenta uma ?Pesquisa-Ação? realizada em uma pesquisa de doutoramento, que utilizou os momentos metodológicos propostos por João Bosco Pinto, sob um referencial do materialismo histórico. Para tanto, o pesquisador-coordenador lançou mão da Teoria das Representações Sociais de Serge Moscovici e outros autores, visando a construção, juntamente com as dez famílias assentadas no Projeto Olga Benário, em Santa Tereza do Oeste, Estado do Paraná, de um determinado conhecimento sobre a área de Reserva Legal (ARL) daquele assentamento, com a finalidade de um possível manejo daquela área em bases sustentáveis.Disponível online
Development of bovine embryos cultured with media containing glucose.
Blastocyst (BL) expansion and blastocoel formation are coupled with increase in the glucose (GLU) metabolism, which is higher in morphologically normal than in degenerate embryos (Rieger et aI., 1992). This study aimed to determine the dose levei and duration of addition of GLU to culture medium that ensures the best results in development of in vitro produced bovine embryos
Blockade of NK-1 receptors in the lateral commissural nucleus tractus solitarii of awake rats had no effect on the cardiovascular responses to chemoreflex activation
Abstract The neurotransmission of the chemoreflex in the nucleus tractus solitarii (NTS), particularly of the sympatho-excitatory component, is not completely understood. There is evidence that substance P may play a role in the neurotransmission of the chemoreflex in the NTS. Microinjection of substance P (50 pmol/50 nl, N = 12, and 5 nmol/50 nl, N = 8) into the commissural NTS of unanesthetized rats produced a significant increase in mean arterial pressure (101 ± 1 vs 108 ± 2 and 107 ± 3 vs 115 ± 4 mmHg, respectively) and no significant changes in heart rate (328 ± 11 vs 347 ± 15 and 332 ± 7 vs 349 ± 13 bpm, respectively) 2 min after microinjection. Previous treatment with WIN, an NK-1 receptor antagonist (2.5 nmol/50 nl), microinjected into the NTS of a specific group of rats, blocked the pressor (11 ± 5 vs 1 ± 2 mmHg) and tachycardic (31 ± 6 vs 4 ± 3 bpm) responses to substance P (50 pmol/50 nl, N = 5) observed 10 min after microinjection. Bilateral microinjection of WIN into the lateral commissural NTS (N = 8) had no significant effect on the pressor (50 ± 4 vs 42 ± 6 mmHg) or bradycardic (-230 ± 16 vs -220 ± 36 bpm) responses to chemoreflex activation with potassium cyanide (iv). These data indicate that the activation of NK-1 receptors by substance P in the NTS produces an increase in baseline mean arterial pressure and heart rate. However, the data obtained with WIN suggest that substance P and NK-1 receptors do not play a major role in the neurotransmission of the chemoreflex in the lateral commissural NTS
Evidence of Low-Temperature Superparamagnetism in Mn_{4}$ Nanoparticle Ensembles
Please refer to the abstract within the main body of the paper
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