77 research outputs found
Reestablishing the income-democracy nexus
A number of recent empirical studies have cast doubt on the "modernization theory" of democratization, which posits that increases in income are conducive to increases in democracy levels. This doubt stems mainly from the fact that while a strong positive correlation exists between income and democracy levels, the relationship disappears when one controls for country fixed effects. This raises the possibility that the correlation in the data reflects a third causal characteristic, such as institutional quality. In this paper, we reexamine the robustness of the income-democracy relationship. We extend the research on this topic in two dimensions: first, we make use of newer income data, which allows for the construction of larger samples with more within-country observations. Second, we concentrate on panel estimation methods that explicitly allow for the fact that the primary measures of democracy are censored with substantial mass at the boundaries, or binary censored variables. Our results show that when one uses both the new income data available and a properly non linear estimator, a statistically significant positive income-democracy relationship is robust to the inclusion of country fixed effects.Income
Helicobacter pylori
Chronic gastritis is an inflammation of the gastric mucosa and has multiple etiologies. Here we discuss the pathological alterations induced by Helicobacter pylori (HP) leading to chronic gastritis and the epigenetic bases underlying these changes. We review the histology of the normal gastric mucosa and overview the role of HP in the multistep cascade of GC. We attempt to define the role of the Operative Link for Gastritis Assessment (OLGA) staging system in assessing the risk of GC. The epigenetic bases of chronic gastritis, mainly DNA methylation, are presented through examples such as (i) the methylation of the promoter region of E-cadherin in HP-induced chronic gastritis and its reversion after HP eradication and (ii) the association of methylation of the promoter region of Reprimo, a p53-mediated cell cycle arrest gene, with aggressive HP strains in high risk areas for GC. In addition, we discuss the finding of RPRM as a circulating cell-free DNA, offering the opportunity for noninvasive risk assessment of GC. Finally, the integration of OLGA and tissue biomarkers, by systems pathology approach, suggests that severe atrophy has a greater risk for GC development if, in addition, overexpressed p73. This trial is registered with ClinicalTrials.gov NCT01774266
Bounding Causal Effects in an Ecological Inference Problem: the Chilean Electoral Reform
This paper is concerned with making causal inferences with ecological data. Aggregate outcome information is combined with individual demographic information from separate data sources to make causal inferences about individual behavior. In addressing such problems, even under the selection on observables assumption often made in the treatment effects literature, it is not possible to identify causal effects of interest. However, recent results from the partial identification literature provide the tightest upper and lower bounds on these causal effects. We apply these bounds to data from Chilean mayoral elections that straddle a 2012 change in Chilean electoral law from compulsory to voluntary voting. Aggregate voting outcomes are combined with individual demographic information from separate data sources to determine the causal effect of the change in the law on voter turnout. The bounds analysis reveals that voluntary voting decreased expected voter turnout, and that other causal effects are overstated if the bounds analysis is ignored
MicroRNA-335-5p and Gastrointestinal Tumors
Noncoding genomics, i.e., microRNAs and long coding RNAs (lncRNA), is an emerging topic in gastrointestinal tumors. In particular, the coordinate deregulation of miRNA-335-5p across these tumors and its potential clinical applications is an example of this scenario. This chapter discusses the pathogenetic role of miRNA-335-5p in esophageal, gastric, colon, liver, gallbladder, and pancreatic tumors. This pathogenetic role is examined in the context of the competing endogenous network, the language through lncRNA that reduce the quantity of miRNA available to target mRNA. The translational application of miRNA-335-5p, through the aberrant methylation of the promoter region of MESTâits host geneâas a potential biomarker for noninvasive detection of gastric cancer, is also discussed
Reestablishing the Income-Democracy Nexus
A number of recent empirical studies have cast doubt on the âmodernization theoryâ of democratization, which posits that increases in income are conducive to increases in democracy levels. This doubt stems mainly from the fact that while a strong positive correlation exists between income and democracy levels, the relationship disappears when one controls for country fixed effects. This raises the possibility that the correlation in the data reflects a third causal characteristic, such as institutional quality. In this paper, we reexamine the robustness of the income-democracy relationship. We extend the research on this topic in two dimensions: first, we make use of newer income data, which allows for the construction of larger samples with more within-country observations. Second, we concentrate on panel estimation methods that explicitly allow for the fact that the primary measures of democracy are censored with substantial mass at the boundaries, or binary censored variables. Our results show that when one uses both the new income data available and a properly non linear estimator, a statistically significant positive income-democracy relationship is robust to the inclusion of country fixed effects.
Consulta AraucanĂa: el uso oportunista de los mecanismos de democracia directa
Els mecanismes de democrĂ cia directa han augmentat la seva presència arreu. Al costat dels beneficis que comporta la participaciĂł ciutadana, aquests mecanismes han reobert la possibilitat dâutilitzar aquestes eleccions amb propòsits mobilitzadors. Aquest article revisa lâĂşs oportunista de la consulta a lâAraucania, realitzada al sud de Xile lâany 2021. Aquesta consulta ciutadana va preguntar sobre una possible extensiĂł de la militaritzaciĂł en el context del conflicte entre lâEstat xilè i el poble maputxe. A partir de lâanĂ lisi estadĂstica, aquest treball mostra que la consulta no va representar les preferències de la regiĂł, sinĂł que va mobilitzar una part dâaquesta en funciĂł dâun objectiu particular. El seus resultats, però, es van interpretar des de la retòrica de la representaciĂł amb finalitats polĂtiques.The mechanisms of direct democracy have increased their presence throughout the world. Along with the benefits that citizen participation entails, these mechanisms have reopened the possibility of using elections for mobilizing purposes. This article reviews the opportunistic use of the Araucanian referendum, carried out in southern Chile in 2021. This citizen consultation asked about a possible extension of the militarization in the context of the conflict between the Chilean state and the Mapuche people. From a statistical analysis, our work shows that the referendum did not represent the region's preferences but rather mobilized a part of it based on a particular objective. Its results, however, were interpreted from the rhetoric of representation with political ends.Los mecanismos de democracia directa han aumentado su presencia en todo el mundo. Junto a los beneficios que conlleva la participaciĂłn ciudadana, estos mecanismos han reabierto la posibilidad de usar elecciones con propĂłsitos movilizadores. Este artĂculo revisa el uso oportunista de la Consulta AraucanĂa, llevada a cabo en el sur de Chile el aĂąo 2021. Esta consulta ciudadana preguntĂł acerca de una posible extensiĂłn de la militarizaciĂłn en el contexto del conflicto entre el Estado chileno y el pueblo mapuche. A partir del anĂĄlisis estadĂstico, nuestro trabajo muestra que la consulta no representĂł las preferencias de la regiĂłn, sino que movilizĂł a una parte de ella en funciĂłn de un objetivo particular. Sus resultados, no obstante, fueron interpretados desde la retĂłrica de la representaciĂłn con fines polĂticos
In Silico analysis of Gastric carcinoma Serial Analysis of Gene Expression libraries reveals different profiles associated with ethnicity
Worldwide gastric carcinoma has marked geographical variations and worse outcome in patients from the West compared to the East. Although these differences has been explained by better diagnostic criteria, improved staging methods and more radical surgery, emerging evidence supports the concept that gene expression differences associated to ethnicity might contribute to this disparate outcome. Here, we collected datasets from 4 normal and 11 gastric carcinoma Serial Gene Expression Analysis (SAGE) libraries from two different ethnicities. All normal SAGE libraries as well as 7 tumor libraries were from the West and 4 tumor libraries were from the East. These datasets we compare by Correspondence Analysis and Support Tree analysis and specific differences in tags expression were identified by Significance Analysis for Microarray. Tags to gene assignments were performed by CGAP-SAGE Genie or TAGmapper. The analysis of global transcriptome shows a clear separation between normal and tumor libraries with 90 tags differentially expressed. A clear separation was also found between the West and the East tumor libraries with 54 tags differentially expressed. Tags to gene assignments identified 15 genes, 5 of them with significant higher expression in the West libraries in comparison to the East libraries. qRT-PCR in cell lines from west and east origin confirmed these differences. Interestingly, two of these genes have been associated to aggressiveness (COL1A1 and KLK10). In conclusion we found that in silico analysis of SAGE libraries from two different ethnicities reveal differences in gene expression profile. These expression differences might contribute to explain the disparate outcome between the West and the East
Epstein-Barr VirusâAssociated Gastric Carcinoma: The Americasâ Perspective
Epstein-Barr virus (EBV) infection has been associated with different malignancies, and compelling evidence has shown that it may have a causative or at least contributing role in gastric carcinogenesis. EBV-associated gastric cancers have a unique molecular signature, which has defined this group of tumors as a distinctive molecular subtype of gastric cancer. This subtype has shown a greater incidence in the Americas than in the Asian countries. This chapter discusses about possible factors underlying these differences and the emerging roles of epigenetics in the pathogenesis of Epstein-Barr virusâassociated gastric cancer
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