Institution
University of Los Andes
Education•Bogotá, Colombia•
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.
Papers published on a yearly basis
Papers
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TL;DR: Although P. aeruginosa may be ubiquitous in nature, it is usually scarce in pristine environments and should be described as a bacterium largely found in locations associated with human activity, according to a systematic review and meta‐analysis of published data.
Abstract: Pseudomonas aeruginosa is generally described as ubiquitous in natural settings, such as soil and water. However, because anecdotal observations and published reports have questioned whether or not this description is true, we undertook a rigorous study using three methods to investigate the occurrence of P. aeruginosa: We investigated environmental samples, analyzed 16S rRNA data, and undertook a systematic review and meta-analysis of published data. The environmental sample screening identified P. aeruginosa as significantly associated with hydrocarbon and pesticide-contaminated environments and feces, as compared to uncontaminated environments in which its prevalence was relatively low. The 16S rRNA data analysis showed that P. aeruginosa sequences were present in all habitats but were most abundant in samples from human and animals. Similarly, the meta-analysis revealed that samples obtained from environments with intense human contact had a higher prevalence of P. aeruginosa compared to those with less human contact. Thus, we found a clear tendency of P. aeruginosa to be present in places closely linked with human activity. Although P. aeruginosa may be ubiquitous in nature, it is usually scarce in pristine environments. Thus, we suggest that P. aeruginosa should be described as a bacterium largely found in locations associated with human activity.
122 citations
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TL;DR: In this article, the authors performed searches for resonant and nonresonant pair-produced Higgs bosons (HH) decaying respectively into l nu l nu, through either W or Z bosons, and b (b) over bar.
Abstract: Searches for resonant and nonresonant pair-produced Higgs bosons (HH) decaying respectively into l nu l nu, through either W or Z bosons, and b (b) over bar are presented The analyses are based on a sample of proton-proton collisions at root s = 13 TeV, collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 359 fb(-1) Data and predictions from the standard model are in agreement within uncertainties For the standard model HH hypothesis, the data exclude at 95% confidence level a product of the production cross section and branching fraction larger than 72 fb, corresponding to 79 times the standard model prediction Constraints are placed on different scenarios considering anomalous couplings, which could affect the rate and kinematics of HH production Upper limits at 95% confidence level are set on the production cross section of narrow-width spin-0 and spin-2 particles decaying to Higgs boson pairs, the latter produced with minimal gravity-like coupling
121 citations
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TL;DR: The results conform to the expectations of the "dominance" rather than "faster male" theories of Haldane's rule and suggest that relatively few loci are responsible for the effect of female sterility.
Abstract: Most genetic studies of Haldane9s rule, in which hybrid sterility or inviability affects the heterogametic sex preferentially, have focused on Drosophila. It therefore remains unclear to what extent the conclusions of that work apply more generally, particularly in female-heterogametic taxa such as birds and Lepidoptera. Here we present a genetic analysis of Haldane9s rule in Heliconius butterflies. Female F 1 hybrids between Heliconius melpomene and H. cydno are completely sterile, while males have normal to mildly reduced fertility. In backcrosses of male F 1 hybrids, female offspring range from completely sterile to fully fertile. Linkage analysis using the Z-linked triose-phosphate isomerase locus demonstrates a “large X” (Z) effect on sterility. Expression of female sterility varies among crosses in this and a previous study of Heliconius. Sterility may result from the production of normal but infertile eggs, production of small infertile eggs, or from a complete failure to develop ovarioles, which suggests multiple routes to the evolution of hybrid sterility in these Heliconius species. These results conform to the expectations of the “dominance” rather than “faster male” theories of Haldane9s rule and suggest that relatively few loci are responsible. The two species are broadly sympatric and hybridize in the wild, so that female hybrid sterility forms one of several strong but incomplete barriers to gene flow in nature. The effect of female sterility is comparable to that of selection against non-mimetic hybrids, while mate choice forms a much stronger barrier to gene transfer.
121 citations
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TL;DR: This paper investigated whether cohorts of children from poor households that benefited up to nine years from a conditional cash transfer program in Colombia, attained more school and performed better on academic tests at the end of high school.
Abstract: Conditional cash transfers are programs under which poor families get a stipend provided they keep their children in school and take them for health checks. Although there is significant evidence showing that they have positive impacts on school participation, little is known about the long-term impacts of the programs on human capital. This paper investigates whether cohorts of children from poor households that benefited up to nine years from Familias en Accion, a conditional cash transfer program in Colombia, attained more school and performed better on academic tests at the end of high school. Identification of program impacts is derived from two different strategies using matching techniques with household surveys, and regression discontinuity design using a census of the poor and administrative records of the program. The authors show that, on average, participant children are 4 to 8 percentage points more likely than nonparticipant children to finish high school, particularly girls and beneficiaries in rural areas. Regarding long-term impact on tests scores, the analysis shows that program recipients who graduate from high school seem to perform at the same level as equally poor non-recipient graduates, even after correcting for possible selection bias when low-performing students enter school in the treatment group. Although the positive impacts on high school graduation may improve the employment and earning prospects of participants, the lack of positive effects on test scores raises the need to further explore policy actions to couple the program's objective of increasing human capital with enhanced learning.
121 citations
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University of Hong Kong1, Deakin University2, University of California, San Diego3, Ghent University4, Baker IDI Heart and Diabetes Institute5, The Catholic University of America6, University of Los Andes7, Auckland University of Technology8, Emory University9, University of Southern Denmark10, University of Canberra11, University of Navarra12
TL;DR: Country-specific modifications to the original scoring protocol of the NEWS/NEWS-A are proposed that enhance inter-country comparability and have yielded sufficiently equivalent measurement models of theNEWS/ NEWS-A.
Abstract: Background: The IPEN (International Physical Activity and Environment Network) Adult project seeks to conduct pooled analyses of associations of perceived neighborhood environment, as measured by the Neighborhood Environment Walkability Scale (NEWS) and its abbreviated version (NEWS-A), with physical activity using data from 12 countries. As IPEN countries used adapted versions of the NEWS/NEWS-A, this paper aimed to develop scoring protocols that maximize cross-country comparability in responses. This information is also highly relevant to non-IPEN studies employing the NEWS/NEWS-A, which is one of the most popular measures of perceived environment globally. Methods: The following countries participated in the IPEN Adult study: Australia, Belgium, Brazil, Colombia, Czech Republic, Denmark, Hong Kong, Mexico, New Zealand, Spain, the United Kingdom, and the United States. Participants (N = 14,305) were recruited from neighborhoods varying in walkability and socio-economic status. Countries collected data on the perceived environment using a self- or interviewer-administered version of the NEWS/NEWS-A. Confirmatory Factor Analysis (CFA) was used to derive comparable country-specific measurement models of the NEWS/NEWS-A. The level of correspondence between standard and alternative versions of the NEWS/NEWS-A factor-analyzable subscales was determined by estimating the correlations and mean standardized difference (Cohen’s d) between them using data from countries that had included items from both standard and alternative versions of the subscales. Results: Final country-specific measurement models of the NEWS/NEWS-A provided acceptable levels of fit to the data and shared the same factorial structure with six latent factors and two single items. The correspondence between the standard and alternative versions of subscales of Land use mix – access, Infrastructure and safety for walking/cycling, and Aesthetics was high. The Brazilian version of the Traffic safety subscale was highly, while the Australian and Belgian versions were marginally, comparable to the standard version. Single-item versions of the Street connectivity subscale used in Australia and Belgium showed marginally acceptable correspondence to the standard version. (Continued on next page)
121 citations
Authors
Showing all 17748 results
Name | H-index | Papers | Citations |
---|---|---|---|
Alexander Belyaev | 142 | 1895 | 100796 |
Sarah Catherine Eno | 141 | 1645 | 105935 |
Mitchell Wayne | 139 | 1810 | 108776 |
Kaushik De | 139 | 1625 | 102058 |
Pierluigi Paolucci | 138 | 1965 | 105050 |
Randy Ruchti | 137 | 1832 | 107846 |
Gabor Istvan Veres | 135 | 1349 | 96104 |
Raymond Brock | 135 | 1468 | 97859 |
Harrison Prosper | 134 | 1587 | 100607 |
J. Ellison | 133 | 1392 | 92416 |
Gyorgy Vesztergombi | 133 | 1444 | 94821 |
Andrew Brandt | 132 | 1246 | 94676 |
Scott Snyder | 131 | 1317 | 93376 |
Shuai Liu | 129 | 1095 | 80823 |
C. A. Carrillo Montoya | 128 | 1033 | 78628 |