832 resultados para cluster-voting
Resumo:
Recent studies on the history of economic development demonstrate that concentration of power on a monarch or a ruling coalition impedes economic growth and that institutional changes that diffuse power, though beneficial to the society in general, are opposed by some social groups. In November 2005, Kenyans rejected a proposed constitution primarily because it did not reduce the powers of the executive to any significant degree. Using data of voting patterns in the constitutional referendum and following the rational choice framework, I estimate a model of the demand for power diffusion and demonstrate that groups voting decisions depend on expected gains and likelihood of monopolizing power. The results also reveal the importance of ethnic divisions in hindering the power diffusion process, and therefore the study establishes a channel through which ethnic fragmentation impacts on economic development.
Resumo:
This paper examines whether the voter with the median income is decisive in local spending decisions. Previous tests have relied on cross-sectional data while we make use of a pair of California referenda to estimate a first difference specification. The referenda proposed to lower the required vote share for passing local educational bonding initiatives from 67 to 50 percent and 67 to 55 percent, respectively. We find that voters rationally consider future public service decisions when deciding how to vote on voting rules, but the empirical evidence strongly suggests that an income percentile below the median is decisive for majority voting rules. This finding is consistent with high income voters with weak demand for public educational services voting with the poor against increases in public spending on education.
Resumo:
Although many studies find that voting in Africa approximates an ethnic census in that voting is primarily along ethnic lines, hardly any of the studies have sought to explain ethnic voting following a rational choice framework. Using data of voter opinions from a survey conducted two weeks before the December 2007 Kenyan elections, we find that the expected benefits associated with a win by each of the presidential candidates varied significantly across voters from different ethnic groups. We hypothesize that decision to participate in the elections was influenced by the expected benefits as per the minimax-regret voting model. We test the predictions of this model using data of voter turnout in the December 2007 elections and find that turnout across ethnic groups varied systematically with expected benefits. The results suggest that individuals participated in the elections primarily to avoid the maximum regret should a candidate from another ethnic group win. The results therefore offer credence to the minimax regret model as proposed by Ferejohn and Fiorina (1974) and refute the Downsian expected utility model.
Resumo:
One of the most critical aspects of G Protein Coupled Receptors (GPCRs) regulation is their rapid and acute desensitization following agonist stimulation. Phosphorylation of these receptors by GPCR kinases (GRK) is a major mechanism of desensitization. Considerable evidence from studies of rhodopsin kinase and GRK2 suggests there is an allosteric docking site for the receptor distinct from the GRK catalytic site. While the agonist-activated GPCR appears crucial for GRK activation, the molecular details of this interaction remain unclear. Recent studies suggested an important role for the N- and C-termini and domains in the small lobe of the kinase domain in allosteric activation; however, neither the mechanism of action of that site nor the RH domain contributions have been elucidated. To search for the allosteric site, we first indentified evolutionarily conserved sites within the RH and kinase domains presumably deterministic of protein function employing evolutionary trace (ET) methodology and crystal structures of GRK6. Focusing on a conserved cluster centered on helices 3, 9, and 10 in the RH domain, key residues of GRK5 and 6 were targeted for mutagenesis and functional assays. We found that a number of double mutations within helices 3, 9, and 10 and the N-terminus markedly reduced (50–90%) the constitutive phosphorylation of the β-2 Adrenergic Receptor (β2AR) in intact cells and phosphorylation of light-activated rhodopsin (Rho*) in vitro as compared to wild type (WT) GRK5 or 6. Based on these results, we designed peptide mimetics of GRK5 helix 9 both computationally and through chemical modifications with the goal of both confirming the importance of helix 9 and developing a useful inhibitor to disrupt the GPCR-GRK interaction. Several peptides were found to block Rho* phosphorylation by GRK5 including the native helix 9 sequence, Peptide Builder designed-peptide preserving only the key ET residues, and chemically locked helices. Most peptidomimetics showed inhibition of GRK5 activity greater than 80 % with an IC50 of ∼ 30 µM. Alanine scanning of helix 9 has further revealed both essential and non-essential residues for inhibition. Importantly, substitution of Arg 169 by an alanine in the native helix 9-based peptide gave an almost complete inhibition at 30 µM with an IC50 of ∼ 10 µM. In summary we report a previously unrecognized crucial role for the RH domain of GRK5 and 6, and the subsequent identification of a lead peptide inhibitor of protein-protein interaction with potential for specific blockade of GPCR desensitization. ^
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Background: Despite almost 40 years of research into the etiology of Kawasaki Syndrome (KS), there is little research published on spatial and temporal clustering of KS cases. Previous analysis has found significant spatial and temporal clustering of cases, therefore cluster analyses were performed to substantiate these findings and provide insight into incident KS cases discharged from a pediatric tertiary care hospital. Identifying clusters from a single institution would allow for prospective analysis of risk factors and potential exposures for further insight into KS etiology. ^ Methods: A retrospective study was carried out to examine the epidemiology and distribution of patients presenting to Texas Children’s Hospital in Houston, Texas, with a diagnosis of Acute Febrile Mucocutaneous Lymph Node Syndrome (MCLS) upon discharge from January 1, 2005 to December 31, 2009. Spatial, temporal, and space-time cluster analyses were performed using the Bernoulli model with case and control event data. ^ Results: 397 of 102,761 total patients admitted to Texas Children’s Hospital had a principal or secondary diagnosis of Acute Febrile MCLS upon over the 5 year period. Demographic data for KS cases remained consistent with known disease epidemiology. Spatial, temporal, and space-time analyses of clustering using the Bernoulli model demonstrated no statistically significant clusters. ^ Discussion: Despite previous findings of spatial-temporal clustering of KS cases, there were no significant clusters of KS cases discharged from a single institution. This implicates the need for an expanded approach to conducting spatial-temporal cluster analysis and KS surveillance given the limitations of evaluating data from a single institution.^
Resumo:
Si bien en el campo de las políticas públicas nacionales la desregulación total de las distintas fases de la cadena vitivinícola emerge como el principal rasgo distintivo de los años noventa, en los principales ámbitos provinciales vinculados con el complejo han ido irrumpiendo algunas políticas y acciones regulatorias tendientes a alentar la reconversión productiva del sector, a promover el consumo y, fundamentalmente, la exportación de los distintos productos vitivinícolas. Un claro ejemplo de ello lo brinda el Tratado celebrado entre las Provincias de Mendoza y San Juan en el mes de noviembre de 1994 (ya en el mes de junio de dicho año, habían suscripto un Acta por la que se proponían realizar esfuerzos comunes en el ordenamiento de la industria vitivinícola), luego convertido en leyes provinciales por ambas cámaras legislativas.Por lo expuesto, el presente trabajo busca analizar el contexto y las causas que llevaron a la aplicación y continuidad del mencionado Acuerdo Interprovincial. Además, se pretende evaluar los resultados obtenidos por el mismo, y la situación actual del problema de sobreoferta de vinos. Los objetivos generales de la investigación son: -Analizar la importancia del cluster vitivinícola para la economía de la provincia de Mendoza y para Argentina misma. -Describir la evolución del sector y evaluar su condición de cluster productivo. En cuanto a los objetivos específicos, se mencionan: -Conocer la teoría referida al concepto de cluster productivo, y verificar si el sector en cuestión puede considerarse como tal. -Analizar las causas y consecuencias que tuvo la implementación del acuerdo interprovincial entre Mendoza y San Juan en el cluster mendocino. -Conocer el contexto que llevó a plantear el acuerdo, y los objetivos que perseguía. -Analizar si el acuerdo fue o no una buena medida para corregir los problemas que se presentaban en el momento y si cumplió sus objetivos. Comparar con las demás medidas barajadas para solucionar el mismo problema del sector (sobreexistencias vínicas).
Resumo:
Multivariate analyses of latest Pliocene through Holocene benthic foraminifera from 61 samples from Deep-Sea Drilling Project (DSDP) Site 214, eastem Indian Ocean were carried out. The 46 highest ranked species were used in R-mode factor analysis which has enabled to the identification of three environmentally significant assemblages at Site 214. Assemblage 1 is characterized by Uvigerina hispido-costata, Osangularia culter , Gavelinopsis lobatulus, Cibicides wuellerstorfi and Karreriella baccata as principal species. This assemblage is inferred to reflect high-energy, well-oxygenated and probably low-organic carbon deep-sea environment at Site 214. Assemblage 2 is defined principally by Globocassidulina pacifica and U. proboscidea and is considered to indicate an organic carbon-rich environment which resulted from high surface productivity irrespective of dissolved oxygen content. Assemblage 3 is marked by Oridorsalis umbonatus, Textularia lythostrota, Hoeglundina elegans, Pyrgo murrhina, and Pullenia quinqueloba as principal species. This assemblage is inferred to indicate a low-organic carbon environment with high pore water oxygen concentration leading to better preservation of deep-sea sediments.