248 research outputs found

    What We Have Learned About Grassroots Philanthropy: Lessons From Mexico

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    Mexico is going through a transition from traditions of authoritarian, top-down social and political management that have tended to marginalize the efforts of community groups in addressing social and environmental challenges. While there are many important questions about strengthening civil society organizations in general, grassroots groups in particular are challenged by the weak enabling environment for social action. Despite this, the Action in Solidarity Fund has found that it is very possible for philanthropists to reach small grassroots groups with the support they need and to begin to strengthen the social fabric for communities to act on their own behalf. This article shares lessons from the fund’s experience in grassroots philanthropy. Effective support must go back to the basics and build trust, networks, and collaboration as key elements of solidarity. Financial support must be built around the objectives, knowledge, and understanding of grassroots groups in order to lay a foundation for them to learn and act on their own initiatives. This financial support needs to be accessible to these groups and to incorporate philanthropic approaches that promote a self-sustaining social capacity to act on issues and priorities

    A comparative study of the incidence of Alternaria Conidia in the atmosphere of five spanish cities

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    The true identity of the new world iguanid lizard liolaemus chillanensis Müller and Hellmich 1932 (Iguania: Liolaemidae) and description of a new species in the liolaemus elongatus group

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    Liolaemus is a particularly species-rich radiation of New World iguanid lizards from southern South America. Thanks to intense systematic and taxonomic research, the knowledge on its species-level diversity has increased rapidly over the past several years. The L. elongatus species-complex has received considerable attention and a remarkable case is Liolaemus chillanensis, a name that has been used for two different species that are sympatric in Termas de Chillán, central Chile. Since the holotype is lost, we propose that the first step to identify the true L. chillanensis is through the analysis of the original description. Then we provide a morphological and molecular characterization of L. chillanensis based on topotypes and a description of the taxon previously confused with it.Fil: Troncoso Palacios, Jaime. Universidad de Chile; ChileFil: Esquerré, Damien. The Australian National University; AustraliaFil: Urra, Félix A.. Universidad de Chile; ChileFil: Díaz, Hugo A.. Universidad de Chile; ChileFil: Castro Pastene, Carlos. Universidad de Concepción; ChileFil: Ruiz, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentin

    Peroxidase expression in a cereal cyst nematode (Heterodera avenae) resistant hexaploid wheat line.

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    The incompatible interaction between plant and pathogen is often determined by the hypersensitive reaction (HR). This response is associated with accumulation of reactive oxygen species (ROS), which results in adverse growth conditions for pathogens. Two major mechanisms involving either NADPH oxidases or peroxidases have been proposed for generation of ROS. Peroxidases (PER, EC 1.11.1.7), present in all land plants, are members of a large multigenic family with high number of isoforms involved in a broad range of physiological processes. PER genes, which are expressed in nematode feeding sites, have been identified in several plant species (Zacheo et al. 1997). A strong correlation between HR and PER activities at four and seven days post nematode infection, was detected in roots of wheat lines carrying Cre2, Cre5 (from Ae. ventricosa) or Cre7 (from Ae. triuncialis) Heterodera avenae resistance genes (Andrés et al. 2001; Montes et al. 2003, 2004). We have studied changes in root of peroxidase mRNAs levels after infection by H. avenae of a wheat/Ae. ven¬tricosa introgression line (H-93-8) carrying Cre2 (Delibes et al. 1993). We also report and classify the predicted protein sequences derived from complete peroxidase transcripts

    Microgrids Power Quality Enhancement Using Model Predictive Control

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    In electric power systems, any deviation with respect to the theoretical sinusoidal waveform is considered to be a disturbance in the power quality of the electrical grid. The deviation can alter any of the parameters of the waveform: frequency, amplitude, and symmetry among phases. Microgrid, as a part of the electric power system, has to contribute providing an adequate current waveform in grid connected-mode, as well as to guarantee similar voltage features than the standard requirement given for public distribution grids under normal exploitation conditions in islanded mode. Adequate power quality supply is necessary for the correct compatibility between all the devices connected to the same grid. In this paper, the power quality of microgrids is managed using a Model Predictive Control (MPC) methodology which regulates the power converters of the microgrids in order to achieve the requirements. The control algorithm is developed for the following microgrids working modes: grid-connected, islanded, and interconnected. The simulation results demonstrate that the proposed methodology improves the transient response in comparison with classical methods in all the working modes, minimizing the harmonic content in the current and the voltage even with the presence of non-balanced and non-harmonic-free three-phase voltage and current systems

    Methionine adenosyltransferase S-nitrosylation is regulated by the basic and acidic amino acids surrounding the target thiol

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    S-Adenosylmethionine serves as the methyl donor for many biological methylation reactions and provides the propylamine group for the synthesis of polyamines. S-Adenosylmethionine is synthesized from methionine and ATP by the enzyme methionine adenosyltransferase. The cellular factors regulating S-adenosylmethionine synthesis have not been well defined. Here we show that in rat hepatocytes S-nitrosoglutathione monoethyl ester, a cell-permeable nitric oxide donor, markedly reduces cellular S-adenosylmethionine content via inactivation of methionine adenosyltransferase by S-nitrosylation. Removal of the nitric oxide donor from the incubation medium leads to the denitrosylation and reactivation of methionine adenosyltransferase and to the rapid recovery of cellular S-adenosylmethionine levels. Nitric oxide inactivates methionine adenosyltransferase via S-nitrosylation of cysteine 121. Replacement of the acidic (aspartate 355) or basic (arginine 357 and arginine 363) amino acids located in the vicinity of cysteine 121 by serine leads to a marked reduction in the ability of nitric oxide to S-nitrosylate and inactivate hepatic methionine adenosyltransferase. These results indicate that protein S-nitrosylation is regulated by the basic and acidic amino acids surrounding the target cysteine
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