Showing papers by "University of Los Andes published in 2010"
Michael R. Hoffmann1, Craig Hilton-Taylor2, Ariadne Angulo2, Monika Böhm3 +170 more•Institutions (81)
TL;DR: Though the threat of extinction is increasing, overall declines would have been worse in the absence of conservation, and current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups.
Abstract: Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species.
1,333 citations
University of British Columbia1, California Institute of Technology2, University of California, Davis3, University of Oxford4, University of California, Los Angeles5, College of DuPage6, University of Los Andes7, University of California, Santa Barbara8, Guilford College9, Providence Health Care10, Washington University in St. Louis11, Florida State University12, University of Colorado Boulder13, Boise State University14
TL;DR: This article found that participation in a world religion is associated with fairness, although not across all measures, and that market integration positively correlates with fairness while community size positively covaries with punishment.
Abstract: Large-scale societies in which strangers regularly engage in mutually beneficial transactions are puzzling. The evolutionary mechanisms associated with kinship and reciprocity, which underpin much of primate sociality, do not readily extend to large unrelated groups. Theory suggests that the evolution of such societies may have required norms and institutions that sustain fairness in ephemeral exchanges. If that is true, then engagement in larger-scale institutions, such as markets and world religions, should be associated with greater fairness, and larger communities should punish unfairness more. Using three behavioral experiments administered across 15 diverse populations, we show that market integration (measured as the percentage of purchased calories) positively covaries with fairness while community size positively covaries with punishment. Participation in a world religion is associated with fairness, although not across all measures. These results suggest that modern prosociality is not solely the product of an innate psychology, but also reflects norms and institutions that have emerged over the course of human history.
884 citations
National Oceanic and Atmospheric Administration1, Silver Spring Networks2, James Cook University3, University of the Virgin Islands4, University of East Anglia5, Mote Marine Laboratory6, Simón Bolívar University7, University of the French West Indies and Guiana8, University of Puerto Rico at Mayagüez9, University of North Carolina at Wilmington10, University of Bedfordshire11, University of Havana12, Griffith University13, University of Magdalena14, University of Miami15, Spanish National Research Council16, Nova Southeastern University17, Smithsonian Tropical Research Institute18, Atlantic Oceanographic and Meteorological Laboratory19, University of Puerto Rico20, University of Exeter21, Bermuda Institute of Ocean Sciences22, National Autonomous University of Mexico23, Boston University24, University of Queensland25, The Nature Conservancy26, University of the West Indies27, Australian National University28, Marine Institute of Memorial University of Newfoundland29, Florida Institute of Technology30, University of California, Los Angeles31, University of Los Andes32, Central University of Venezuela33, Brown University34, Universiti Malaysia Terengganu35
TL;DR: Comparison of satellite data against field surveys demonstrated a significant predictive relationship between accumulated heat stress (measured using NOAA Coral Reef Watch's Degree Heating Weeks) and bleaching intensity.
Abstract: Background: The rising temperature of the world's oceans has become a major threat to coral reefs globally as the severity and frequency of mass coral bleaching and mortality events increase. In 2005, high ocean temperatures in the tropical Atlantic and Caribbean resulted in the most severe bleaching event ever recorded in the basin. Methodology/Principal Findings: Satellite-based tools provided warnings for coral reef managers and scientists, guiding both the iming and location of researchers' field observations as anomalously warm conditions developed and spread across the greater Caribbean region from June to October 2005. Field surveys of bleaching and mortality exceeded prior efforts in detail and extent, and provided a new standard for documenting the effects of bleaching and for testing nowcast and forecast products. Collaborators from 22 countries undertook the most comprehensive documentation of basin-scale bleaching to date and found that over 80% of corals bleached and over 40% died at many sites. The most severe bleaching coincided with waters nearest a western Atlantic warm pool that was centered off the northern end of the Lesser Antilles. Conclusions/Significance: Thermal stress during the 2005 event exceeded any observed from the Caribbean in the prior 20 years, and regionally-averaged temperatures were the warmest in over 150 years. Comparison of satellite data against field surveys demonstrated a significant predictive relationship between accumulated heat stress (measured using NOAA Coral Reef Watch's Degree Heating Weeks) and bleaching intensity. This severe, widespread bleaching and mortality will undoubtedly have long-term consequences for reef ecosystems and suggests a troubled future for tropical marine ecosystems under a warming climate.
755 citations
Vardan Khachatryan, Albert M. Sirunyan, Armen Tumasyan, Wolfgang Adam1 +2197 more•Institutions (149)
TL;DR: The pre-print version of the Published Article can be accessed from the link below - Copyright @ 2010 Springer Verlag as discussed by the authors, which can be viewed as a preprint of the published article.
Abstract: This is the pre-print version of the Published Article, which can be accessed from the link below - Copyright @ 2010 Springer Verlag
717 citations
TL;DR: In this paper, the authors present a model of the political budget cycle in which incumbents try to influence voters by changing the composition of government spending, rather than overall spending or revenues.
564 citations
University of Leeds1, Environmental Change Institute2, Museu Paraense Emílio Goeldi3, National University of Colombia4, Conservation International5, Missouri Botanical Garden6, Centre de coopération internationale en recherche agronomique pour le développement7, Institut national de la recherche agronomique8, Universidad Nacional de la Amazonía Peruana9, University of Edinburgh10, National Institute of Amazonian Research11, University of York12, University of Los Andes13, University of Bayreuth14, Universidade Federal do Acre15, Xishuangbanna Tropical Botanical Garden16, University of Yaoundé I17, Humboldt University of Berlin18, Utrecht University19
TL;DR: It is indicated that repeated droughts would shift the functional composition of tropical forests toward smaller, denser-wooded trees, suggesting the existence of moisture stress thresholds beyond which some tropical forests would suffer catastrophic tree mortality.
Abstract: The rich ecology of tropical forests is intimately tied to their moisture status. Multi-site syntheses can provide a macro-scale view of these linkages and their susceptibility to changing climates. Here, we report pan-tropical and regional-scale analyses of tree vulnerability to drought. We assembled available data on tropical forest tree stem mortality before, during, and after recent drought events, from 119 monitoring plots in 10 countries concentrated in Amazonia and Borneo. In most sites, larger trees are disproportionately at risk. At least within Amazonia, low wood density trees are also at greater risk of drought-associated mortality, independent of size. For comparable drought intensities, trees in Borneo are more vulnerable than trees in the Amazon. There is some evidence for lagged impacts of drought, with mortality rates remaining elevated 2 yr after the meteorological event is over. These findings indicate that repeated droughts would shift the functional composition of tropical forests toward smaller, denser-wooded trees. At very high drought intensities, the linear relationship between tree mortality and moisture stress apparently breaks down, suggesting the existence of moisture stress thresholds beyond which some tropical forests would suffer catastrophic tree mortality.
499 citations
Vardan Khachatryan, Albert M. Sirunyan, Armen Tumasyan, Wolfgang Adam1 +2087 more•Institutions (132)
TL;DR: In this article, the authors measured the transverse momentum and pseudorapidity distributions in proton-proton collisions at root s = 7 TeV with the inner tracking system of the CMS detector at the LHC.
Abstract: Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at root s = 7 TeV are measured with the inner tracking system of the CMS detector at the LHC. The charged-hadron yield is obtained by counting the number of reconstructed hits, hit pairs, and fully reconstructed charged-particle tracks. The combination of the three methods gives a charged-particle multiplicity per unit of pseudorapidity dN(ch)/d eta vertical bar(vertical bar eta vertical bar<0.5) = 5.78 +/- 0.01(stat) +/- 0.23(stat) for non-single-diffractive events, higher than predicted by commonly used models. The relative increase in charged-particle multiplicity from root s = 0.9 to 7 TeV is [66.1 +/- 1.0(stat) +/- 4.2(syst)]%. The mean transverse momentum is measured to be 0.545 +/- 0.005(stat) +/- 0.015(syst) GeV/c. The results are compared with similar measurements at lower energies.
464 citations
TL;DR: The aim of this study is to review in detail the most-used PFCOCs, their formulation, and preclinical and clinical trials, and to reflect upon causes of failure and strategies to overcome such failures.
Abstract: A viable blood substitute is still of great necessity throughout the world. Perfluorocarbon-based oxygen carriers (PFCOCs) are emulsions that take advantage of the high solubility of respiratory gases in perfluorocarbons (PFCs). Despite attractive characteristics, no PFCOC is currently approved for clinical uses. Some PFCOCs have failed due to secondary effects of the surfactants employed, like Fluosol DA, whereas others to adverse cerebrovascular effects on cardiopulmonary bypass, such as Oxygent. Further in-depth, rigorous work is needed to overcome the annotated failures and to obtain a safe PFCOC approved for human use. The aim of this study is to review in detail the most-used PFCOCs, their formulation, and preclinical and clinical trials, and to reflect upon causes of failure and strategies to overcome such failures.
271 citations
TL;DR: A positive link between early ATL and individual trajectories of reading and math performance was found and children's early ATL was equally beneficial for children regardless of their race/ethnicity and dimensions of their socioeconomic background.
Abstract: Children's early approaches to learning (ATL) enhance their adaptation to the demands they experience with the start of formal schooling. The current study uses individual growth modeling to investigate whether children's early ATL, which includes persistence, emotion regulation, and attentiveness, explain individual differences in their academic trajectories during elementary school. Using data from the Early Childhood Longitudinal Study - Kindergarten Cohort (ECLS-K), the present investigation examined the association between ATL at kindergarten entry and trajectories of reading and math achievement across 6 waves of data from kindergarten, 1st, 3rd, and 5th grade (n = 10,666). The current study found a positive link between early ATL and individual trajectories of reading and math performance. Overall, children's early ATL was equally beneficial for children regardless of their race/ethnicity and dimensions of their socioeconomic background. However, links between early ATL and academic trajectories differed by their gender and initial levels of math and reading achievement.
263 citations
TL;DR: In this article, a large number of published and unpublished datasets (n=81 sites) were used to assess the determinants of litterfall variation across South American tropical forests, showing that litterfall averages 8.61±1.91 Mg ha−1 yr−1 (mean ± standard deviation, in dry mass units).
Abstract: . The production of aboveground soft tissue represents an important share of total net primary production in tropical rain forests. Here we draw from a large number of published and unpublished datasets (n=81 sites) to assess the determinants of litterfall variation across South American tropical forests. We show that across old-growth tropical rainforests, litterfall averages 8.61±1.91 Mg ha−1 yr−1 (mean ± standard deviation, in dry mass units). Secondary forests have a lower annual litterfall than old-growth tropical forests with a mean of 8.01±3.41 Mg ha−1 yr−1. Annual litterfall shows no significant variation with total annual rainfall, either globally or within forest types. It does not vary consistently with soil type, except in the poorest soils (white sand soils), where litterfall is significantly lower than in other soil types (5.42±1.91 Mg ha−1 yr−1). We also study the determinants of litterfall seasonality, and find that it does not depend on annual rainfall or on soil type. However, litterfall seasonality is significantly positively correlated with rainfall seasonality. Finally, we assess how much carbon is stored in reproductive organs relative to photosynthetic organs. Mean leaf fall is 5.74±1.83 Mg ha−1 yr−1 (71% of total litterfall). Mean allocation into reproductive organs is 0.69±0.40 Mg ha−1 yr−1 (9% of total litterfall). The investment into reproductive organs divided by leaf litterfall increases with soil fertility, suggesting that on poor soils, the allocation to photosynthetic organs is prioritized over that to reproduction. Finally, we discuss the ecological and biogeochemical implications of these results.
241 citations
TL;DR: In this paper, the anchoring domain of FimH interacts with the mannose-binding (lectin) domain and causes a twist in the beta sandwich fold of the latter, resulting in an inactive low-affinity state of the adhesin.
Vardan Khachatryan, Albert M. Sirunyan, Armen Tumasyan, Wolfgang Adam1 +2067 more•Institutions (134)
TL;DR: In this article, the trajectories of charged particles produced in the collisions were reconstructed using the all-silicon Tracker and their momenta were measured in the 3.8 T axial magnetic field.
Abstract: The first LHC pp collisions at centre-of-mass energies of 0.9 and 2.36 TeV were recorded by the CMS detector in December 2009. The trajectories of charged particles produced in the collisions were reconstructed using the all-silicon Tracker and their momenta were measured in the 3.8 T axial magnetic field. Results from the Tracker commissioning are presented including studies of timing, efficiency, signal-to-noise, resolution, and ionization energy. Reconstructed tracks are used to benchmark the performance in terms of track and vertex resolutions, reconstruction of decays, estimation of ionization energy loss, as well as identification of photon conversions, nuclear interactions, and heavy-flavour decays.
TL;DR: In this article, the authors evaluate the capital-structure determinants of Latin American firms using a comprehensive sample covering seven countries and find a positive relation between leverage and ownership concentration, when losing control becomes an issue.
TL;DR: Objective and perceived neighborhood characteristics could provide insight into potential interventions among older adults from rapidly urbanizing settings in Latin America.
TL;DR: It is speculated that the suppressive effects of MSC-induced Treg cells might be dependent on a more inflammatory milieu, becoming clinically evident in patients with higher degrees of disease activity.
Abstract: Mesenchymal stem cells (MSCs) exert suppressive effects in several disease models including lupus prone mice. However, autologous MSC therapy has not been tested in human systemic lupus erythematosus (SLE). We evaluate the safety and efficacy of bone marrow (BM)-derived MSCs in two SLE patients; the suppressor effect of these cells in-vitro and the change in CD4+CD25+FoxP3+ T regulatory (Treg) cells in response to treatment. Two females (JQ and SA) of 19 and 25 years of age, fulfilling the 1997 American College of Rheumatology (ACR) criteria for SLE were infused with autologous BM-derived MSCs. Disease activity indexes and immunological parameters were assessed at baseline, 1, 2, 7 and 14 weeks. Peripheral blood lymphocyte (PBL) subsets and Treg cells were quantitated by flow cytometry, and MSCs tested for in-vitro suppression of activation and proliferation of normal PBLs. No adverse effects or change in disease activity indexes were noted during 14 weeks of follow-up, although circulating Treg cells increased markedly. Patient MSCs effectively suppressed in-vitro PBL function. However, JQ developed overt renal disease 4 months after infusion. MSC infusion was without adverse effects, but did not modify initial disease activity in spite of increasing CD4+CD25+FoxP3+ cell counts. One patient subsequently had a renal flare. We speculate that the suppressive effects of MSC-induced Treg cells might be dependent on a more inflammatory milieu, becoming clinically evident in patients with higher degrees of disease activity.
TL;DR: Certain built and perceived environment characteristics were associated with walking among older adults living in Bogotá and further studies should be conducted to better understand the potential influence of the built environment on physical activity among the elderly population in the context of Latin American cities.
TL;DR: This article showed that plants have significantly earlier divergence time estimates than animals for historical migration events across the Isthmus of Panama region, indicating that plants had a greater propensity for dispersal over the isthmus before its closure compared with animals.
Abstract: The “Great American Biotic Interchange” (GABI) is regarded as a defining event in the biogeography of the Americas. It is hypothesized to have occurred when the Isthmus of Panama closed ca three million years ago (Ma), ending the isolation of South America and permitting the mixing of its biota with that of North America. This view of the GABI is based largely upon the animal fossil record, but recent molecular biogeographic studies of plants that show repeated instances of long-distance dispersal over major oceanic barriers suggest that perhaps the land bridge provided by the isthmus may have been less necessary for plant migration. Here we show that plants have significantly earlier divergence time estimates than animals for historical migration events across the Isthmus of Panama region. This difference in timing indicates that plants had a greater propensity for dispersal over the isthmus before its closure compared with animals. The GABI was therefore asynchronous for plants and animals, which has fundamental implications for the historical assembly of tropical biomes in the most species-rich forests on the planet.
TL;DR: In this paper, the authors measured the charge asymmetry of like-sign dimuon events in 6.1 fb(-1) of p (p) over bar collisions recorded with the D0 detector at a center-of-mass energy root s = 1: 96 TeV at the Fermilab Tevatron collider.
Abstract: We measure the charge asymmetry A =(N++ -N--)/(N++ + N--) of like-sign dimuon events in 6.1 fb(-1) of p (p) over bar collisions recorded with the D0 detector at a center-of-mass energy root s = 1: 96 TeV at the Fermilab Tevatron collider. From A we extract the like-sign dimuon charge asymmetry in semileptonic b-hadron decays: A(sl)(b) = -0.009 57 +/- 0.00251(stat) +/- 0.001 46(sys). It differs by 3.2 standard deviations from the standard model prediction A(sl)(b)(SM) = (-2.3(-0.6)(+0.5)) x 10(-4), and provides first evidence of anomalous CP violation in the mixing of neutral B mesons.
TL;DR: In this article, the authors proposed two simple models of CME geometry that can be used to derive information about the azimuthal deflection and the expansion of the CMEs from simultaneous observations by multiple heliospheric imagers.
Abstract: We discuss how simultaneous observations by multiple heliospheric imagers (HIs) can provide some important information about the azimuthal properties of coronal mass ejections (CMEs) in the heliosphere. We propose two simple models of CME geometry that can be used to derive information about the azimuthal deflection and the azimuthal expansion of CMEs from SECCHI/HI observations. We apply these two models to four CMEs well observed by both STEREO spacecraft during the year 2008. We find that in three cases, the joint STEREO-A and B observations are consistent with CMEs moving radially outward. In some cases, we are able to derive the azimuthal cross section of the CME fronts, and we are able to measure the deviation from self-similar evolution. The results from this analysis show the importance of having multiple satellites dedicated to space weather forecasting, for example, in orbits at the Lagrangian L4 and L5 points.
TL;DR: These results exclude a standard model Higgs boson in the mass range 162-166 GeV at the 95% C.L.V. level, and resulting limits on Higgs Boson production are excluded.
Abstract: We combine searches by the CDF and D0 Collaborations for a Higgs boson decaying to W+W-. The data correspond to an integrated total luminosity of 4.8 (CDF) and 5.4 (D0) fb(-1) of p (p) over bar collisions at root s = 1.96 TeV at the Fermilab Tevatron collider. No excess is observed above background expectation, and resulting limits on Higgs boson production exclude a standard model Higgs boson in the mass range 162-166 GeV at the 95% C.L.
TL;DR: In this article, the authors employ a household-level survey administered to 2,322 Colombian displaced households to estimate changes in household welfare after displacement and assess aggregate consumption levels in destination sites.
TL;DR: In this article, the fraction of events with double parton scattering (f_DP) in a single ppbar collision at sqrt{s}=1.96 TeV was determined.
Abstract: We have used a sample of photon+3 jets events collected by the D0 experiment with an integrated luminosity of about 1 fb^-1 to determine the fraction of events with double parton scattering (f_DP) in a single ppbar collision at sqrt{s}=1.96 TeV. The DP fraction and effective cross section (sigma_eff), a process-independent scale parameter related to the parton density inside the nucleon, are measured in three intervals of the second (ordered in pT) jet transverse momentum pT_jet2 within the range 15 < pT_jet2 < 30 GeV. In this range, f_DP varies between 0.23 < f_DP < 0.47, while sigma_eff has the average value sigma_eff_ave = 16.4 +- 0.3(stat) +- 2.3(syst) mb.
TL;DR: In this article, the authors evaluate the effects of maternal vs. alternative care providers' time inputs on children's cognitive development using the sample of single mothers in the National Longitudinal Survey of Youth.
TL;DR: Ciclovías have potential for positive public health outcomes, but evidence on their effectiveness is limited and the different stages of new and established programs offer a unique opportunity for transnational studies aimed at assessing their public health impact.
Abstract: Background: The Ciclovia-Recreativa is a free, community-based program in which streets are closed temporarily to motorized transport, allowing access to walkers, runners, rollerbladers, and cyclists only. We assessed existing information about the Ciclovia as a public health strategy and proposed next steps for research and public health practice. Methods: We conducted a systematic search of peer-reviewed and other literature, which was complemented by expert interviews and consultation. Results: We reviewed 38 Ciclovias from 11 countries. Most programs (84.2%) take place in urban settings. The programs range from 18–64 events per year (54 ± 24.6; 52 [mean ± standard deviation; median]) with events lasting from 2–12 hours (6 ± 2.4; 6). The length of the streets ranges from 1–121 km (14.6 ± 22.1; 7), and the estimated number of participants per event ranges from 60-1,000,000 persons (61,203 ± 186,668; 3810). Seventy-one percent of the programs include physical activity classes and in 89% of the Ciclovias, the streets are connected with parks. Conclusions: Ciclovias have potential for positive public health outcomes, but evidence on their effectiveness is limited. The different stages of new and established programs offer a unique opportunity for transnational studies aimed at assessing their public health impact.
TL;DR: The discovery of genetic variability within TcI showed the presence of five genotypes related to the transmission cycle of Chagas disease, which corroborate the predominance of TCI in Colombia and show the first report of TcIII and TcIV in Colombian ChagAsic patients.
Abstract: Chagas disease caused by Trypanosoma cruzi is a complex disease that is endemic and an important problem in public health in Latin America. The T. cruzi parasite is classified into six discrete taxonomic units (DTUs) based on the recently proposed nomenclature (TcI, TcII, TcIII, TcIV, TcV and TcVI). The discovery of genetic variability within TcI showed the presence of five genotypes (Ia, Ib, Ic, Id and Ie) related to the transmission cycle of Chagas disease. In Colombia, TcI is more prevalent but TcII has also been reported, as has mixed infection by both TcI and TcII in the same Chagasic patient. The objectives of this study were to determine the T. cruzi DTUs that are circulating in Colombian chronic Chagasic patients and to obtain more information about the molecular epidemiology of Chagas disease in Colombia. We also assessed the presence of electrocardiographic, radiologic and echocardiographic abnormalities with the purpose of correlating T. cruzi genetic variability and cardiac disease. Molecular characterization was performed in Colombian adult chronic Chagasic patients based on the intergenic region of the mini-exon gene, the 24Sα and 18S regions of rDNA and the variable region of satellite DNA, whereby the presence of T.cruzi I, II, III and IV was detected. In our population, mixed infections also occurred, with TcI-TcII, TcI-TcIII and TcI-TcIV, as well as the existence of the TcI genotypes showing the presence of genotypes Ia and Id. Patients infected with TcI demonstrated a higher prevalence of cardiac alterations than those infected with TcII. These results corroborate the predominance of TcI in Colombia and show the first report of TcIII and TcIV in Colombian Chagasic patients. Findings also indicate that Chagas cardiomyopathy manifestations are more correlated with TcI than with TcII in Colombia.
TL;DR: The phylogenetic structure of antbird assemblages cannot be explained by the history of speciation and dispersal of antbirds, further supporting the habitat-filtering hypothesis and emphasizing the importance of including trait information in studies of phylogenetic community structure to adequately assess the mechanisms that determine species co-existence.
Abstract: 1. Methods that assess patterns of phylogenetic relatedness, as well as character distribution and evolution, allow one to infer the ecological processes involved in community assembly. Assuming niche conservatism, assemblages should shift from phylogenetic clustering to evenness with decreasing geographic scale because the relative importance of mechanisms that shape assemblages is hypothesized to be scale-dependent. Whereas habitat filtering is more likely to act at regional scales because of increased habitat heterogeneity that allows sorting of ecologically similar species in contrasting environments, competition is more likely to act at local scales because low habitat heterogeneity provides few opportunities for niche partitioning. 2. We used species lists to assess assemblage composition, data on ecologically-relevant traits, and a molecular phylogeny, to examine the phylogenetic structure of antbird (Thamnophilidae) assemblages at three different geographical scales: regional (ecoregions), intermediate (100-ha plots) and local (mixed-flocks). In addition, we used patterns of phylogenetic beta diversity and beta diversity to separate the factors that structure antbird assemblages at regional scales. 3. Contrary to previous findings, we found a shift from phylogenetic evenness to clustering with decreasing geographical scale. We argue that this does not reject the hypothesis that habitat filtering is the predominant force in regional community assembly, because analyses of trait evolution and structure indicated a lack of niche conservatism in antbirds. 4. In some cases, phylogenetic evenness at regional scales can be an effect of historical biogeographic processes instead of niche-based processes. However, regional patterns of beta diversity and phylogenetic beta diversity suggested that phylogenetic structure in our study cannot be explained by the history of speciation and dispersal of antbirds, further supporting the habitat-filtering hypothesis. 5. Our analyses suggested that competitive interactions might not play an important role locally, which would provide a plausible explanation for the high alpha diversity of antbirds in Amazonia. 6. Finally, we emphasize the importance of including trait information in studies of phylogenetic community structure to adequately assess the mechanisms that determine species co-existence.
TL;DR: The data suggest that modulation of DC function by aldosterone enhances CD8+ T cell activation and promotes Th17-polarized immune responses, which might contribute to the inflammatory damage leading to hypertension and cardiovascular disease.
Abstract: Excessive production of aldosterone leads to the development of hypertension and cardiovascular disease by generating an inflammatory state that can be promoted by T cell immunity. Because nature and intensity of T cell responses is controlled by dendritic cells (DCs), it is important to evaluate whether the function of these cells can be modulated by aldosterone. In this study we show that aldosterone augmented the activation of CD8(+) T cells in a DC-dependent fashion. Consistently, the mineralocorticoid receptor was expressed by DCs, which showed activation of MAPK pathway and secreted IL-6 and TGF-beta in response to aldosterone. In addition, DCs stimulated with aldosterone impose a Th17 phenotype to CD4(+) T cells, which have recently been associated with the promotion of inflammatory and autoimmune diseases. Accordingly, we observed that aldosterone enhances the progression of experimental autoimmune encephalomyelitis, an autoimmune disease promoted by Th17 cells. In addition, blockade of the mineralocorticoid receptor prevented all aldosterone effects on DCs and attenuated experimental autoimmune encephalomyelitis development in aldosterone-treated mice. Our data suggest that modulation of DC function by aldosterone enhances CD8(+) T cell activation and promotes Th17-polarized immune responses, which might contribute to the inflammatory damage leading to hypertension and cardiovascular disease.
TL;DR: The sensitivity and specificity of the Pan-E Dengue Early ELISA and the Platelia™ Dengue NS1 Ag assays were compared against a reference diagnosis in 1385 patients in 6 countries in Asia and the Americas as discussed by the authors.
Abstract: Background
Early diagnosis of dengue can assist patient triage and management and prevent unnecessary treatments and interventions. Commercially available assays that detect the dengue virus protein NS1 in the plasma/serum of patients offers the possibility of early and rapid diagnosis.
Methodology/Principal Findings
The sensitivity and specificity of the Pan-E Dengue Early ELISA and the Platelia™ Dengue NS1 Ag assays were compared against a reference diagnosis in 1385 patients in 6 countries in Asia and the Americas. Platelia was more sensitive (66%) than Pan-E (52%) in confirmed dengue cases. Sensitivity varied by geographic region, with both assays generally being more sensitive in patients from SE Asia than the Americas. Both kits were more sensitive for specimens collected within the first few days of illness onset relative to later time points. Pan-E and Platelia were both 100% specific in febrile patients without evidence of acute dengue. In patients with other confirmed diagnoses and healthy blood donors, Platelia was more specific (100%) than Pan-E (90%). For Platelia, when either the NS1 test or the IgM test on the acute sample was positive, the sensitivity versus the reference result was 82% in samples collected in the first four days of fever. NS1 sensitivity was not associated to disease severity (DF or DHF) in the Platelia test, whereas a trend for higher sensitivity in DHF cases was seen in the Pan-E test (however combined with lower overall sensitivity).
Conclusions/Significance
Collectively, this multi-country study suggests that the best performing NS1 assay (Platelia) had moderate sensitivity (median 64%, range 34–76%) and high specificity (100%) for the diagnosis of dengue. The poor sensitivity of the evaluated assays in some geographical regions suggests further assessments are needed. The combination of NS1 and IgM detection in samples collected in the first few days of fever increased the overall dengue diagnostic sensitivity.
TL;DR: The proposed memetic algorithm couples genetic operators and local search procedures proven to be effective on deterministic routing problems with a novel individual evaluation and reparation strategy that accounts for the stochastic nature of the problem.
Vardan Khachatryan, Albert M. Sirunyan, Armen Tumasyan, Wolfgang Adam1 +2196 more•Institutions (147)
TL;DR: In this article, a search for narrow resonances in the dijet mass spectrum is performed using data corresponding to an integrated luminosity of 2.9 inverse pb collected by the CMS experiment at the LHC.
Abstract: A search for narrow resonances in the dijet mass spectrum is performed using data corresponding to an integrated luminosity of 2.9 inverse pb collected by the CMS experiment at the LHC. Upper limits at the 95% confidence level (CL) are presented on the product of the resonance cross section, branching fraction into dijets, and acceptance, separately for decays into quark-quark, quark-gluon, or gluon-gluon pairs. The data exclude new particles predicted in the following models at the 95% CL: string resonances, with mass less than 2.50 TeV, excited quarks, with mass less than 1.58 TeV, and axigluons, colorons, and E_6 diquarks, in specific mass intervals. This extends previously published limits on these models.