2,836 research outputs found
Economic burden of air pollution in Colombia
To estimate indirect costs related to the loss of productivity due to premature mortality associated with air quality risk factors in Colombia, 2016. We estimated potential productivity years of life lost (PPYLL) related to indoor (biomass fuels) and outdoor pollution (PM2.5 and ozone). We analyzed deaths records of the Departamento Administrativo Nacional de EstadÃstica, 2016, with the following basic causes of death related to air quality risk factors: isquemic hearth disease (IHD), cardiovascular disease (CD), lower respiratory tract infections (LRTI), lung cancer (LC) and chronic obstructive pulmonary disease(COPD), according to ICD-10. PPYLL were valued considering the productive age in Colombia, which ranges from 18-57 years for women and up to 62 for men. Three scenarios were built: lower loss (minimum legal wage), average loss [one per capita gross domestic product (GDPpc)] and higher loss (three GDPpc). PPYLL for the mentioned causes were multiplied by the fraction attributable to each air risk factor. The latest were estimated from IDEAM (outdoor) and the survey of Quality of Life 2016 and systematic reviews (indoor pollution). Costs were reported in American dollars, using the December 31 (2016) exchange rate: 1USD=3,000.7 Colombian Pesos. The economic burden due to premature deaths caused by the analyzed diseases was US444,320,058-150,585,143 (83.007.582. The second with the highest economic burden attributable to air quality risk factors was CD (US22,077,091), LC (US5,840,495). The exposure to PM2.5 particulate matter represented the largest share of the economic burden attributable to air quality risk factors. Our estimations suggest that premature deaths caused by exposure to air qualityrisk factors represented 0.052% of GDP for 2016
The environmental fate of organic pollutants through the global microbial metabolism
The production of new chemicals for industrial or therapeutic applications exceeds our ability to generate experimental data on their biological fate once they are released into the environment. Typically, mixtures of organic pollutants are freed into a variety of sites inhabited by diverse microorganisms, which structure complex multispecies metabolic networks. A machine learning approach has been instrumental to expose a correlation between the frequency of 149 atomic triads (chemotopes) common in organo-chemical compounds and the global capacity of microorganisms to metabolise them. Depending on the type of environmental fate defined, the system can correctly predict the biodegradative outcome for 73–87% of compounds. This system is available to the community as a web server (http://www.pdg.cnb.uam.es/BDPSERVER). The application of this predictive tool to chemical species released into the environment provides an early instrument for tentatively classifying the compounds as biodegradable or recalcitrant. Automated surveys of lists of industrial chemicals currently employed in large quantities revealed that herbicides are the group of functional molecules more difficult to recycle into the biosphere through the inclusive microbial metabolism
Drainage And Sedimentary Response Of The Northern Andes And The Pebas System To Miocene Strike-slip Tectonics: A Source To Sink Study Of The Magdalena Basin
Miocene strike-slip tectonics was responsible for creating and closing short-lived (ca. 6 Ma) passages and the emergence of isolated topography in the Northern Andes. These geological events likely influenced the migration and/or isolation of biological populations. To better understand the paleogeography of the Miocene hinterland and foreland regions in the Northern Andes, we conducted a source-to-sink approach in the Magdalena Basin. This basin is located between the Central and Eastern Cordilleras of Colombia and contains an ample Miocene record, which includes Lower Miocene fine-grained strata and Middle Miocene to Pliocene coarsening-up strata. Our study presents a new data set that includes detrital U–Pb zircon ages (15 samples), sandstone petrography (45 samples) and low-temperature thermochronology from the Southern Central Cordillera (19 dates); which together with previously published data were used to construct a paleogeographical model of the Miocene hinterland and foreland regions in the Northern Andes. The evolution of the Magdalena Basin during the Miocene was characterized by playa and permanent lake systems at ca. 17.5 Ma, which may be related to a marine incursion into NW South America and western Amazonia. The appearance of Eocene to Miocene volcanic sources in the Honda Group after ca. 16 Ma suggests the development of fluvial passages, which connected the Pacific with the western Amazonia and Caribbean regions. These passages were synchronous with a time of Miocene exhumation and topographic growth (ca. 16 to 10 Ma) in the Central Cordillera and the transition from lacustrine to fluvial deposition in the Magdalena Basin. Middle to Late Miocene strike-slip deformation promoted by oblique plate convergence and the oblique collision of the Panamá-Chocó Block likely explains the synchronous along-strike fragmentation and exhumation in the Central Cordillera
Role of the employment status and education of mothers in the prevalence of intestinal parasitic infections in Mexican rural schoolchildren
<p><b>Background:</b> Intestinal parasitic infections are a public health problem in developing countries such as Mexico. As a result, two governmental programmes have been implemented: a) "National Deworming Campaign" and b) "Opportunities" aimed at maternal care. However, both programmes are developed separately and their impact is still unknown. We independently investigated whether a variety of socio-economic factors, including maternal education and employment levels, were associated with intestinal parasite infection in rural school children.</p>
<p><b>Methods:</b> This cross-sectional study was conducted in 12 rural communities in two Mexican states. The study sites and populations were selected on the basis of the following traits: a) presence of activities by the national administration of albendazole, b) high rates of intestinal parasitism, c) little access to medical examination, and d) a population having less than 2,500 inhabitants. A total of 507 schoolchildren (mean age 8.2 years) were recruited and 1,521 stool samples collected (3 per child). Socio-economic information was obtained by an oral questionnaire. Regression modelling was used to determine the association of socio-economic indicators and intestinal parasitism.</p>
<p><b>Results:</b> More than half of the schoolchildren showed poliparasitism (52%) and protozoan infections (65%). The prevalence of helminth infections was higher in children from Oaxaca (53%) than in those from Sinaloa (33%) (p < 0.0001). Giardia duodenalis and Hymenolepis nana showed a high prevalence in both states. Ascaris lumbricoides, Trichuris trichiura and Entamoeba hystolitica/dispar showed low prevalence. Children from lower-income families and with unemployed and less educated mothers showed higher risk of intestinal parasitism (odds ratio (OR) 6.0, 95% confidence interval (CI) 1.6–22.6; OR 4.5, 95% CI 2.5–8.2; OR 3.3, 95% CI 1.5–7.4 respectively). Defecation in open areas was also a high risk factor for infection (OR 2.4, 95% CI 2.0–3.0).</p>
<p><b>Conclusion:</b> Intestinal parasitism remains an important public health problem in Sinaloa (north-western Mexico) and Oaxaca (south-eastern Mexico). Lower income, defecation in open areas, employment status and a lower education level of mothers were the significant factors related to these infections. We conclude that mothers should be involved in health initiatives to control intestinal parasitism in Mexico.</p>
The physical meaning of scattering matrix singularities in coupled-channel formalisms
The physical meaning of bare and dressed scattering matrix singularities has
been investigated. Special attention has been attributed to the role of well
known invariance of scattering matrix with respect to the field transformation
of the effective Lagrangian. Examples of evaluating bare and dressed quantities
in various models are given.Comment: 14 pages, Summary of the BRAG2007 worksho
Measurement of Total and Differential Cross Sections of Neutrino and Antineutrino Coherent Production on Carbon
Neutrino induced coherent charged pion production on nuclei,
, is a rare inelastic interaction in
which the four-momentum squared transfered to the nucleus is nearly zero,
leaving it intact. We identify such events in the scintillator of MINERvA by
reconstructing |t| from the final state pion and muon momenta and by removing
events with evidence of energetic nuclear recoil or production of other final
state particles. We measure the total neutrino and antineutrino cross sections
as a function of neutrino energy between 2 and 20 GeV and measure flux
integrated differential cross sections as a function of , and
. The dependence and equality of the neutrino and
anti-neutrino cross-sections at finite provide a confirmation of Adler's
PCAC hypothesis
MINERvA neutrino detector response measured with test beam data
The MINERvA collaboration operated a scaled-down replica of the solid
scintillator tracking and sampling calorimeter regions of the MINERvA detector
in a hadron test beam at the Fermilab Test Beam Facility. This article reports
measurements with samples of protons, pions, and electrons from 0.35 to 2.0
GeV/c momentum. The calorimetric response to protons, pions, and electrons are
obtained from these data. A measurement of the parameter in Birks' law and an
estimate of the tracking efficiency are extracted from the proton sample.
Overall the data are well described by a Geant4-based Monte Carlo simulation of
the detector and particle interactions with agreements better than 4%, though
some features of the data are not precisely modeled. These measurements are
used to tune the MINERvA detector simulation and evaluate systematic
uncertainties in support of the MINERvA neutrino cross section measurement
program.Comment: as accepted by NIM
Measurements of the inclusive neutrino and antineutrino charged current cross sections in MINERvA using the low-nu flux method
The total cross sections are important ingredients for the current and future neutrino oscillation experiments. We present measurements of the total charged-current neutrino and antineutrino cross sections on scintillator (CH) in the NuMI low-energy beamline using an in situ prediction of the shape of the flux as a function of neutrino energy from 2-50 GeV. This flux prediction takes advantage of the fact that neutrino and antineutrino interactions with low nuclear recoil energy (nu) have a nearly constant cross section as a function of incident neutrino energy. This measurement is the lowest energy application of the low-nu flux technique, the first time it has been used in the NuMI antineutrino beam configuration, and demonstrates that the technique is applicable to future neutrino beams operating at multi-GeVenergies. The cross section measurements presented are the most precise measurements to date below 5 GeV
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