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Hajat S.,London School of Hygiene and Tropical Medicine | Sheridan S.C.,Kent State University | Allen M.J.,Kent State University | Pascal M.,Institute of Veille Sanitaire | And 7 more authors.
American Journal of Public Health | Year: 2010

Objectives. We compared the ability of several heat-health warning systems to predict days of heat-associated mortality using common data sets. Methods. Heat-health warning systems initiate emergency public health interventions once forecasts have identified weather conditions to breach predetermined trigger levels. We examined 4 commonly used trigger-setting approaches: (1) synoptic classification, (2) epidemiologic assessment of the temperature-mortality relationship, (3) temperature-humidity index, and (4) physiologic classification. We applied each approach in Chicago, Illinois; London, United Kingdom; Madrid, Spain; and Montreal, Canada, to identify days expected to be associated with the highest heat-related mortality. Results. We found little agreement across the approaches in which days were identified as most dangerous. In general, days identified by temperature-mortality assessment were associated with the highest excess mortality. Conclusions. Triggering of alert days and ultimately the initiation of emergency responses by a heat-health warning system varies significantly across approaches adopted to establish triggers.

De Linares C.,Autonomous University of Barcelona | De Linares C.,Institute Diagnostico Ambiental y Estudios del Agua | Belmonte J.,Autonomous University of Barcelona | Canela M.,IESE Business School | And 5 more authors.
Agricultural and Forest Meteorology | Year: 2010

Alternaria is a common airborne phytopathogenic fungus that may affect crops in the field or can cause decay of plant products. It can also cause diseases in animals and humans. The study of airborne Alternaria conidia is a necessary step for the control and prevention of the agricultural damage they can provoke. The aim of this paper is to contribute to model the presence and levels of Alternaria conidia in the air using a logistic regression model. Our study is conducted in 12 monitoring stations in Spain corresponding to three geographic regions with different bio-climatic characteristics, which show three different patterns of Alternaria conidia dynamics: a unique main sporulation season from mid spring to autumn in NE Spain, two defined periods (spring and autumn) in SE Spain and a uniform and constant presence in the Canary Islands. Regarding the abundance, NE Spain shows the highest values and the Canary Islands the lowest.Daily Alternaria conidia concentration is positively correlated to daily minimum temperature and daily temperature variation and negatively correlated to daily precipitation. Also, the occurrence of rain in the 3 previous days has a positive effect on Alternaria levels. These effects are modelled in this paper by means of logit regression equations. The three equations used apply to the presence of Alternaria conidia, and to the exceedance of thresholds of 10 and 30conidia/m3. The model is calibrated in the 12 stations using data from years 1995 to 2008 and validated with data from 2009 in 7 stations, showing a reasonable percentage of right prediction (average 78.6%, ranging from 61.3% to 92.5%). © 2010 Elsevier B.V.

Novoa A.M.,University Pompeu Fabra | Perez K.,CIBER ISCIII | Santamarina-Rubio E.,Biomedical Research Institute Sant Pau | Mari-Dell'Olmo M.,CIBER ISCIII | And 6 more authors.
American Journal of Public Health | Year: 2010

Objectives. We assessed the effectiveness of the penalty points system (PPS) introduced in Spain in July 2006 in reducing traffic injuries. Methods. We performed an evaluation study with an interrupted time-series design. We stratified dependent variables-numbers of drivers involved in injury collisions and people injured in traffic collisions in Spain from 2000 to 2007 (police data)-by age, injury severity, type of road user, road type, and time of collision, and analyzed variables separately by gender. The explanatory variable (the PPS) compared the postintervention period (July 2006 to December 2007) with the preintervention period (January 2000 to June 2006). We used quasi- Poisson regression, controlling for time trend and seasonality. Results. Among men, we observed a significant risk reduction in the postintervention period for seriously injured drivers (relative risk [RR]=0.89) and seriously injured people (RR=0.89). The RRs among women were 0.91 (P=.095) and 0.88 (P<.05), respectively. Risk reduction was greater among male drivers, moped riders, and on urban roads. Conclusions. The PPS was associated with reduced numbers of drivers involved in injury collisions and people injured by traffic collisions in Spain.

De Soto I.S.,Public University of Navarra | Ayora C.,Institute Diagnostico Ambiental y Estudios Del Agua | Cuevas J.,Autonomous University of Madrid
Clay Minerals | Year: 2014

Clays are commonly used as liners in urban landfills. However, the reactive processes with landfill leachates, and in particular the role of accessory minerals is poorly known. The aim of this work is to evaluate the diffusion of a synthetic urban landfill leachate through compacted natural smectite-illitic clays containing carbonates and sulfates and to predict the functioning of the clay liner for different minor mineral proportions. The leachate, characterized by acidic pH conditions and high organic matter content, is a typical aqueous solution formed in the acetogenic phase of organic matter degradation in urban landfill areas. Medium-scale (11 cm) laboratory diffusion tests were performed over 77 days. Chloride diffusion coefficients, porosity changes, cation exchange constants and the sulfate reduction rate were quantitatively assessed by means of reactive transport modelling. The exchange capacity of the clays is responsible for NH+ 4 retention. However, the presence or absence of gypsum in the initial clay rock controls the functioning of the liner. Gypsum dissolution ensures a high sulfate concentration in the porewater and enhances the acetate consumption via sulfate reduction. Gypsum dissolution and the concomitant calcite precipitation do not significantly alter the porosity of the clay rock. © 2014 Mineralogical Society.

Hoff R.B.,Laboratorio Nacional Agropecuario | Hoff R.B.,Federal University of Rio Grande do Sul | Meneghini L.,Laboratorio Nacional Agropecuario | Pizzolato T.M.,Federal University of Rio Grande do Sul | And 4 more authors.
Analytical Chemistry | Year: 2014

Four previously unreported metabolism products of sulfaquinoxaline (SQX), a widely used veterinary medicine, were isolated and analyzed using liquid chromatography coupled to high-resolution Orbitrap mass spectrometry. Metabolites were structurally elucidated, and a fragmentation pathway was proposed. The combination of high-resolution MS2 spectra, linear ion trap MS2, in-source collision-induced dissociation (CID) fragmentation, and photolysis were used to analyze SQX and its metabolites. All metabolism products identified showed a similar fragmentation pattern to that of the original drug. Differential product ions were produced at m/z 162 and 253 which contain the radical moiety with more 16 Da units than sulfaquinoxaline. This occurs by a hydroxyl attachment to the quinoxaline moiety. With the exception of two low-intensity compounds, all the mass errors were below 5.0 ppm. The distribution of these metabolites in some animal species are also presented and discussed. © 2014 American Chemical Society.

Estelles V.,University of Valencia | Martinez-Lozano J.A.,University of Valencia | Pey J.,Institute Diagnostico Ambiental y Estudios Del Agua | Sicard M.,Polytechnic University of Catalonia | And 7 more authors.
Journal of Geophysical Research: Atmospheres | Year: 2012

Although routinely monitored by ground based air quality networks, the particulate matter distribution could be eventually better described with remote sensing techniques. However, valid relationships between ground level and columnar ground based quantities should be known beforehand. In this study we have performed a comparison between particulate matter measurements at ground level at different cut sizes (10, 2.5 and 1.0 m), and the aerosol optical depth obtained by means of a ground based sunphotometer during a multiinstrumental field campaign held in El Arenosillo (Huelva, Spain) from 28 June to 4 July 2006. All the PM fractions were very well correlated with AOD with correlation coefficients that ranged from 0.71 to 0.81 for PM10, PM2.5 and PM1. Furthermore, the influence of the mixing layer height in the correlations was explored. The improvement in the correlation when the vertical distribution is taken into account was significant for days with a homogeneous mixing layer. Moreover, the chemical analysis of the individual size fractions allowed us to study the origin of the particulate matter. Secondary components were the most abundant and also well correlated in the three size fractions; but for PM10 fraction, chemical species related to marine origin were best correlated. Finally, we obtained a relationship between MODIS L3 AOD from collection 5.1 and the three PM cut sizes. In spite of being a relatively clean environment, all the techniques were able to capture similar day to day variations during this field campaign. Copyright 2012 by the American Geophysical Union.

De Soto I.S.,Autonomous University of Madrid | Ruiz A.I.,Autonomous University of Madrid | Ayora C.,Institute Diagnostico Ambiental y Estudios del Agua | Garcia R.,Autonomous University of Madrid | And 2 more authors.
Applied Geochemistry | Year: 2012

Diffusion of a synthetic urban landfill leachate through compacted natural illitic clays and the role of reactive accessory minerals (carbonates and gypsum) in the geochemical behavior of major soluble ions are evaluated. The leachate is composed of NH 4 + and Na + (0.25M) balanced by Cl - (0.25M), acetate (0.1M) and HCO3- (0.15M). The pH is 7.8 and it is typical of the mature stage of organic matter degradation within an urban landfill. Laboratory scale diffusion tests were performed over 4months (long term experiment, LT) and 2weeks (short term experiment, ST). The ST experiments were designed to allow the measurement of the Cl - gradient as a diffusion tracer in the compacted clay. In the LT experiments the chemical gradients were already at steady state, but geochemical reactions involving dissolution of gypsum and precipitation of calcite were observed. Evolution of pore-water chemistry, mineralogy, cation exchange properties, and the specific surface of clays were determined. Numerical simulations were carried out using the geochemical code RETRASO. Chloride transport, precipitation of carbonates, pH buffering, and Ca 2+/NH 4 +cation exchange reactions took place in the laboratory tests. Apparent Cl - diffusion coefficients were determined by direct modeling of the ST tests and validated with the LT experiments. These coefficients were considered in the simulation of transport coupled with experimentally calculated exchange constants and dissolution/precipitation reactions of gypsum and carbonates. Sulfate reduction coupled with acetate oxidation has been proven to be relevant in the sample with significant concentration of SO 4 2- (Bailén). This process also includes significant precipitation of carbonates (mainly calcite) and causes a decrease of SO 4 2- in the porewater. © 2012 Elsevier Ltd.

Guarracino L.,National University of La Plata | Carrera J.,Institute Diagnostico Ambiental y Estudios del Agua | Vazquez-Sune E.,Institute Diagnostico Ambiental y Estudios del Agua
Journal of Hydrology | Year: 2012

Head response to sea level fluctuations has been extensively used for characterizing coastal aquifers. When the aquifer is semiconfined and extends for a certain distance . D under the sea, head response results from the superposition of two types of effects: hydraulic (i.e., ground water flow connection through aquifer and aquitard) and mechanical (induced by tidal loading onto the sea floor). Solutions are available for this problem that has been analyzed before, but only for . D zero or infinity. These solutions do not allow analyzing aquifer systems that extends for a finite . D, or identifying them, which is critical for coastal aquifer management. We derive an exact analytical solution that describes separately the mechanical and hydraulic effects. The proposed analytical solution is a generalization of most of existing analytical solutions. A simpler approximate analytical solution is also obtained for soft aquitards with low permeabilities. We find that the impact of the hydraulic component of the aquitard and the mechanical effects in the total head fluctuation at the shoreline is significant, but not very sensitive to the properties of the aquitard. The amplitude of these fluctuations relative to that of the sea tide ranges approximately between 1 (small . D) and 0.5 (large . D). This implies that aquifer penetration under the sea can indeed be identified if it is below a certain threshold, beyond which the system responds as if . D was infinity. Surprisingly, the time lag is close to zero regardless of hydraulic parameters of the aquifer system. © 2012 Elsevier B.V.

Aim. To determine if women with multiple sclerosis (MS) reported an increased risk of breast cancer compared with the general female population. Patients and methods. We conducted a systematic review and meta-analysis of observational cohort studies. We performed a search in PubMed/Medline of studies where standardized incidence ratios (SIRs) were provided. Overall estimates of the SIRs (meta-SIRs) were calculated using DerSimonian-Laird random effects models. Sources of heterogeneity were explored by means sub-groups analyses. Results. Five studies met the inclusion criteria. Women with MS were not associated with increased risk of overall (meta-SIR = 0.80; 95% confidence interval, 95% CI = 0.61-1.06) and breast cancers (meta-SIR = 1.02; 95% CI = 0.75-1.40). These differences did not turn out to be statistically significant. A high degree of heterogeneity between studies was found (I2 = 88.7% and I2 = 75.3%, respectively). Conclusions. The data shown here suggest a similar risk of breast cancer in women with MS when compared to the general population. Further research is required to evaluate the role of specific risk factors at cancer sites such as effects of treatments used in the management of MS patients. © 2010 Revista de Neurología.

Matamoros V.,University of Girona | Matamoros V.,University of Barcelona | Jover E.,Institute Diagnostico Ambiental y Estudios del Agua | Bayona J.M.,University of Barcelona
Analytical Chemistry | Year: 2010

An analytical procedure based on comprehensive two-dimensional gas chromatography (GC × GC) coupled with time-of-flight mass spectrometry (TOF-MS) for the simultaneous determination of 97 organic contaminants at trace concentration in river water is presented. The target analytes included 13 pharmaceuticals, 18 plasticizers, 8 personal care products, 9 acid herbicides, 8 triazines, 10 organophosphorous compounds, 5 phenylureas, 12 organochlorine biocides, 9 polycyclic aromatic hydrocarbons (PAHs), and 5 benzothiazoles and benzotriazoles. The best resolution of the target analytes in the contour plots was obtained when a nonpolar stationary phase was used in the first dimension and polar one in the second. However, in the opposite configuration, polar-nonpolar, the retention time in the second dimension exhibited a strong correlation with the log Kow (p < 0.01), and it was proposed as an additional identification criteria. The developed methodology is based on a polymeric solidphase extraction followed by in GC-port methylation and GC × GC/TOF-MS determination. Moreover, limits of detection (LODs) and quantification (LOQs) ranged from 0.5 to 100 ng/L and from 2 to 185 ng/L, respectively. Repeatability was always lower than 20%. Finally, the developed method has been successfully applied to the determination of incurred target analytes in four river waters subjected to a different anthropogenic pressure. © 2010 American Chemical Society.

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