University of Los Andes

About: University of Los Andes is a education organization based out in Bogotá, Colombia. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 17616 authors who have published 25555 publications receiving 413463 citations.

Perceived neighborhood environmental attributes associated with walking and cycling for transport among adult residents of 17 cities in 12 countries: the IPEN study

Abstract: IntroductionPrevalence of walking and cycling for transport is low and varies greatly across countries. Few studies have examined neighborhood perceptions related to walking and cycling for transpo...

Multicentre prospective study on dengue classification in four South-east Asian and three Latin American countries

Abstract: OBJECTIVE To evaluate the existing WHO dengue classification across all age groups and a wide geographical range and to develop a revised evidence-based classification that would better reflect clinical severity. METHODS We followed suspected dengue cases daily in seven countries across South-east Asia and Latin America and then categorised them into one of three intervention groups describing disease severity according to the overall level of medical and nursing support required. Using a pre-defined analysis plan, we explored the clinical and laboratory profiles characteristic of these intervention categories and presented the most promising options for a revised classification scheme to an independent group of WHO dengue experts for consideration. Potential warning signs were also evaluated by comparing contemporaneous data of patients who progressed to severe disease with the data of those who did not. RESULTS A total of 2259 patients were recruited during 2006-2007 and 230 (13%) of the 1734 laboratory-confirmed patients required major intervention. Applying the existing WHO system, 47/210 (22%) of patients with shock did not fulfil all the criteria for dengue haemorrhagic fever. However, no three-tier revision adequately described the different severity groups either. Inclusion of readily discernible complications (shock/severe vascular leakage and/or severe bleeding and/or severe organ dysfunction) was necessary to devise a system that identified patients requiring major intervention with sufficient sensitivity and specificity to be practically useful. Only a small number of subjects (5%) progressed to severe disease while under observation; several warning signs were identified, but much larger studies are necessary to fully characterize features associated with disease progression. CONCLUSIONS Based on these results, a revised classification system comprised of two entities, 'Dengue' and 'Severe Dengue', was proposed and has now been incorporated into the new WHO guidelines.

Search for heavy neutrinos and W bosons with right-handed couplings in proton-proton collisions at sqrt(s) = 8 TeV

Abstract: A search for heavy, right-handed neutrinos, $$\mathrm {N}_{\ell }$$ ( $$\ell = \mathrm {e}, \mu $$ ), and right-handed $$\mathrm {W}_{\mathrm {R}}$$ bosons, which arise in the left-right symmetric extensions of the standard model, has been performed by the CMS experiment. The search was based on a sample of two lepton plus two jet events collected in proton–proton collisions at a center-of-mass energy of 8 $$\,\text {TeV}$$ corresponding to an integrated luminosity of 19.7 $$\mathrm{fb}^{-1}$$ . For models with strict left-right symmetry, and assuming only one $$\mathrm {N}_{\ell }$$ flavor contributes significantly to the $$\mathrm {W}_{\mathrm {R}}$$ decay width, the region in the two-dimensional $$(M_{\mathrm {W}_{\mathrm {R}}}, M_{\mathrm {N}_{\ell }})$$ mass plane excluded at a 95 % confidence level extends to approximately $$M_{\mathrm {W}_{\mathrm {R}}} = 3.0\,\text {TeV} $$ and covers a large range of neutrino masses below the $$\mathrm {W}_{\mathrm {R}}$$ boson mass, depending on the value of $$M_{\mathrm {W}_{\mathrm {R}}}$$ . This search significantly extends the $$(M_{\mathrm {W}_{\mathrm {R}}}, M_{\mathrm {N}_{\ell }})$$ exclusion region beyond previous results.

Corporate Governance and Firm Value: The Case of Venezuela

Abstract: Manuscript Type: Empirical Research Question/Issue: We examine the relationship between corporate governance and firm value, and evaluate the relatively understudied governance practices in Venezuela. Research Findings/Results: We construct a corporate governance index (CGI) for publicly-listed firms that is free of self-selection and self-reported bias and find that its mean value is below the emerging market average in general, and below the Latin American average in particular. This weak investor protection environment makes Venezuela a good setting to study how corporate governance practices affect firm value. We show that an increase of 1 per cent in the CGI results in an average increase of 11.3 per cent in dividend payouts, 9.9 per cent in price-to-book, and 2.7 per cent in Tobin's Q. These findings are robust after considering the potential endogeneity of our regression variables. Theoretical Implications: Results contrast to those reported in the US due to the higher interfirm variations in CGI. Our findings are consistent with the theoretical models that relate good corporate governance practices to higher investor confidence, and with the agency model of dividend payout. Furthermore, we conjecture that our results are generalizable mainly to other countries where investor protection is low. Practical Implications: Two direct insights to policy makers and practitioners follow from our analysis: first, managers in weak investor protection environments could differentiate their firms adopting corporate policies to improve their governance structure; and second, our measure of governance practices gives investors a quantitative tool to better assess Venezuelan firms.