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Copyright of Huisarts En Wetenschap is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At city level, personal monitoring is the best way to assess people's exposure. However, it is usually estimated from a few monitoring stations. Our aim was to determine the exposure to black carbon ( BC) and BC dose for 45 schoolchildren with portable microaethalometers and to evaluate the relationship between personal monitoring and fixed stations at schools (indoor and outdoor) and in an urban background ( UB) site. Personal BC concentra-tions were 20% higher than in fixed stations at schools. Linear mixed-effect models showed low R2 between personal measurements and fixed stations at schools ( R2 ≤ 0.28), increasing to R2 ≥ 0.70 if considering only periods when children were at schools. For the UB station, the respective R2 were 0.18 and 0.45, indicating the importance of the distance to the monitoring station when assessing exposure. During the warm season, the fixed stations agreed better with personal measurements than during the cold one. Children spent 6% of their time on commuting but received 20% of their daily BC dose, due to co-occurrence with road traffic rush hours and the close proximity to the source. Children received 37% of their daily-integrated BC dose at school. Indoor environments (classroom and home) were responsible for the 56% BC dose. [ABSTRACT FROM AUTHOR]

Aims: To assess the impacts of Ailanthus altissima and Robinia pseudoacacia on the whole litterfall process and on soil properties of riparian ecosystems of Central Spain by comparing invaded and non-invaded forests. Methods: We selected 3-4 plots of four different types of forests: invaded by A. altissima or R. pseudoacacia, or dominated by the native Fraxinus angustifolia or Populus alba. In each plot we collected the litter monthly over 2 years and separated the litter from different plant organs. We calculated annual inputs of litter, nitrogen (N) and phosphorus (P) to soil. We also analyzed soil pH, organic matter (OM), N and P. Results: Most litter fractions from the two invasive trees contained over twice as much N as those from the native P. alba. Although not significantly different, the annual inputs of N in invaded forests were 1.7-2.2 times higher than in native forests. In the invaded forests, extra litterfall peaks were found in summer and/or late-spring (June), corresponding to reproductive and/or leaf litter fractions. The percentage of annual litter represented by these peaks was over twice those in native forests. Soil OM, N and P were higher in invaded than in P. alba forests. In addition, forests invaded by R. pseudoacacia had higher soil OM and N than F. angustifolia forests. Conclusions: This study showed the capability of A. altissima and R. pseudoacacia to alter soil properties and litterfall dynamics in riparian ecosystems. [ABSTRACT FROM AUTHOR]

Hepatitis C virus ( HCV) infection is frequent among patients with alcohol use disorders. We aimed to analyse the impact of HCV infection on survival of patients seeking treatment for alcohol use. This was a longitudinal study in a cohort of patients who abused alcohol recruited in two detoxification units. Socio-demographic and alcohol use characteristics, liver function tests for the assessment of alcohol-related liver disease and HCV and HIV infection serologies were obtained at admission. Patients were followed until December 2008; causes of death were ascertained through clinical records and death registry. Cox models were used to analyse predictors of death. A total of 675 patients (79.7% men) were admitted; age at admission was 43.5 years ( IQR: 37.9-50.2 years), duration of alcohol abuse was 18 years ( IQR: 11-24 years), and median alcohol consumption was 200 g/day ( IQR: 120-275 g/day). Distribution of patients according to viral infections was as follows: 75.7% without HCV or HIV infection, 14.7% HCV infection alone and 8.1% HCV/ HIV coinfection. Median follow-up was 3.1 years ( IQR: 1.5-5.1 years) accounting for 2,345 person-years. At the end of study, 78 patients (11.4%) had died. In the multivariate analysis, age at admission ( HR = 1.71, 95% CI: 1.05-2.80), alcohol-related liver disease ( HR = 3.55, 95% CI: 1.93-6.53) and HCV/ HIV co-infection ( HR = 3.86 95% CI: 2.10-7.11) were predictors of death. Younger patients (≤43 years) with HCV infection were more likely to die than those without viral infections ( HR = 3.1, 95% CI: 1.3-7.3; P = 0.007). Among patients with alcohol-related liver disease, mortality rate was high, irrespective of viral infections. These data show that HCV infection confers a worse prognosis in patients with alcohol use disorders. [ABSTRACT FROM AUTHOR]

The mass concentration, chemical composition and sources of quasi-ultrafine (quasi-UFP, PM0.25), accumulation (PM0.25-2.5) and coarse mode (PM2.5-10) particles were determined in indoor and outdoor air at 39 schools in Barcelona (Spain). Quasi-UFP mass concentrations measured (25.6 µgm-3 outdoors, 23.4 µgm-3 indoors) are significantly higher than those reported in other studies, and characterised by higher carbonaceous and mineral matter contents and a lower proportion of secondary inorganic ions. Results suggest that quasi-UFPs in Barcelona are affected by local sources in the schools, mainly human activity (e.g. organic material from textiles, etc., contributing 23-46% to total quasi-UFP mass) and playgrounds (in the form of mineral matter, contributing about 9% to the quasi-UFP mass). The particle size distribution patterns of toxicologically relevant metals and major aerosol components was characterised, displaying two modes for most elements and components, and one mode for inorganic salts (ammonium nitrate and sulfate) and elemental carbon (EC). Regarding metals, Ni and Cr were partitioned mainly in quasi-UFPs and could thus be of interest for epidemiological studies, given their high redox properties. Exposure of children to quasi-UFP mass and chemical species was assessed by comparing the concentrations measured at urban background and traffic areas schools. Finally, three main indoor sources across all size fractions were identified by assessing indoor/outdoor ratios (I/O) of PM species used as their tracers: human activity (organic material), cleaning products, paints and plastics (Cl- source), and a metallic mixed source (comprising combinations of Cu, Zn, Co, Cd, Pb, As, V and Cr). Our results support the need to enforce targeted legislation to determine a minimum "safe" distance between major roads and newly built schools to reduce exposure to traffic-derived metals in quasi-UFPs. [ABSTRACT FROM AUTHOR]

Copyright of Revista del Centro de Investigación. Universidad La Salle is the property of Universidad La Salle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Centro de Investigación. Universidad La Salle is the property of Universidad La Salle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Centro de Investigación. Universidad La Salle is the property of Universidad La Salle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Centro de Investigación. Universidad La Salle is the property of Universidad La Salle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Centro de Investigación. Universidad La Salle is the property of Universidad La Salle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Centro de Investigación. Universidad La Salle is the property of Universidad La Salle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista del Centro de Investigación. Universidad La Salle is the property of Universidad La Salle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The mass concentration, chemical composition and sources of quasi-ultrafine (quasi-UFP, PM0.25), accumulation (PM0.25-2.5) and coarse mode (PM2.5-10) particles were determined in indoor and outdoor air at 39 schools in Barcelona (Spain). Quasi-UFP mass concentrations measured (25.6 μgm-3 outdoors, 23.4 μgm-3 indoors) are significantly higher than those reported in other studies, and characterised by higher carbonaceous and mineral matter contents and a lower proportion of secondary inorganic ions. Results suggest that quasi-UFPs in Barcelona are affected by local sources in the schools, mainly human activity (e.g. organic material from textiles, etc.; contributing 23-46% to total quasi-UFP mass) and playgrounds (in the form of mineral matter, contributing about 9% to the quasi-UFP mass). The particle size distribution of toxicologically relevant metals and major aerosol components was characterised, displaying bimodal size distributions for most elements and components, and a unimodal distribution for inorganic salts (ammonium nitrate and sulphate) and elemental carbon (EC). Regarding metals, Ni and Cr were partitioned mainly in quasi-UFPs and could thus be of interest for epidemiological studies, given their high redox properties. Children exposure to quasi-UFP mass and chemical species was assessed by comparing the concentrations measured at urban background and traffic areas schools. Finally, three main indoor sources across all size fractions were identified by assessing indoor/outdoor ratios (I/O) of PM species used as their tracers: human activity (organic material), cleaning products, paints and plastics (Cl- source), and a metallic mixed source (comprising combinations of Cu, Zn, Co, Cd, Pb, As, V and Cr). [ABSTRACT FROM AUTHOR]

The present work is part of the INMA (INfancia y Medio Ambiente –‘Environment and Childhood’) project, which aims at assessing the adverse effects of exposure to air pollution during pregnancy and early in life. The present study was performed in the city of Sabadell (Northeast Spain) at three sampling sites covering different traffic characteristics, during two times of the year. It assesses time and spatial variations of PM2.5 concentrations, chemical components and source contributions, as well as gaseous pollutants. Furthermore, a cross-correlation analysis of PM components and source contributions with gaseous pollutants used as a proxy for exposure assessment is carried out. Our data show the influence of traffic emissions in the Sabadell area. The main PM sources identified by Positive Matrix Factorisation (PMF) were similar between the two seasons: mineral source (traffic-induced resuspension, demolition/construction and natural background), secondary sulphate (higher in summer), secondary nitrate (only during winter), industrial, and road traffic, which was the main contributor to PM2.5 at two of the sites. The correlation of concentrations of nitrogen oxides was especially strong with those of elemental carbon (EC). The relatively weaker correlations with organic carbon (OC) in summer are attributed to the variable formation of secondary OC. Strong correlations between concentration of nitrogen oxides and PM2.5 road traffic contributions obtained from source apportionment analysis were seen at all sites. Therefore, under the studied urban environment, nitrogen oxides can be used as a proxy for the exposure to road traffic contribution to PM2.5; the use of NOx concentrations being preferred, with NO and NO2 as second and third options, respectively. [ABSTRACT FROM AUTHOR]

SUMMARYIn vitro tests have been developed for the diagnosis of tuberculosis (TB) infection. The objective was to analyse latent TB infection in drug and alcohol abusers through two interferon-gamma techniques. One hundred and thirty-nine patients were admitted between February 2006 and May 2007. Mean age was 39.8 years [31% HIV positive]. The enzyme immunoassay (EIA) and enzyme-linked immunospot (ELISPOT) interferon-gamma assays were positive in 34% of patients with an agreement of 83% (kappa=0.63). Tuberculin skin test (TST) was positive in 29% of patients and the agreement of TST with EIA and ELISPOT interferon-gamma assays was 85% (kappa=0.62) and 83% (kappa=0.57), respectively. Almost 50% of patients with history of TB had a positive in vitro test. In conclusion, we observed a high prevalence of latent TB and good agreement between the new in vitro tests that otherwise may continue to be positive long after developing TB disease. [ABSTRACT FROM AUTHOR]

In vitro tests have been developed for the diagnosis of tuberculosis (TB) infection. The objective was to analyse latent TB infection in drug and alcohol abusers through two interferon-γ techniques. One hundred and thirty-nine patients were admitted between February 2006 and May 2007. Mean age was 39.8 years [31% HIV positive]. The enzyme immunoassay (EIA) and enzyme-linked immunospot (ELISPOT) interferon-γ assays were positive in 34% of patients with an agreement of 83% (κ=0.63). Tuberculin skin test (TST) was positive in 29% of patients and the agreement of TST with EIA and ELISPOT interferon-κ assays was 85% (κ=0.62) and 83% (κ=0.57), respectively. Almost 50% of patients with history of TB had a positive in vitro test. In conclusion, we observed a high prevalence of latent TB and good agreement between the new in vitro tests that otherwise may continue to be positive long after developing TB disease. [ABSTRACT FROM AUTHOR]

Differential scanning calorimetry was used to study the influence of an epoxy reactive diluent, vinylcyclohexane dioxide, on the curing reaction of a polymeric system composed of diglycidyl ether of bisphenol A ( n=0) and 1,2-diaminecyclohexane (DCH). Heat evolution and glass transition temperature, were measured in terms of the added diluent percentage. Experimental results show that both the curing degree and the glass transition temperature of the polymeric system decrease with an increase in the diluent percentage. Dynamic mechanical analysis of several samples also showed that T g decreases with the increase of diluent percentage, thus corroborating DSC measurements. [ABSTRACT FROM AUTHOR]

The study of the degradation of a polymer is important because it can determine the upper temperature limit, the mechanism of a solid-state process, and the life-time for this system. Since the behavior of thermosets is affected by the selection of the curing cycle, it is important to investigate the changes which take place during the thermal degradation of these materials when a change on the sequence of time and temperature is introduced during the curing reaction. In this work, the thermal degradation of two epoxy systems diglycidyl ether of bisphenol A (BADGE n=0)/1, 2 diamine cyclohexane (DCH) cured through different sequences of time and temperature was studied by thermogravimetric analysis in order to determine the reaction mechanism of the degradation processes, and also to check the influence of the curing cycle on this mechanism. Values obtained using different kinetic methods were compared to the value obtained by Kissinger’s method (differential method which do not require a knowledge of the n-order reaction mechanism), and to that obtained through Flynn–Wall–Ozawa method in a previous work. [ABSTRACT FROM AUTHOR]

In this paper we have studied the behaviour of polyvinyl pyrrolidone (PVP) in the water(1)/DMF(2) binary mixture by differential refractometry and laser light scattering. No inversion has been found on the preferential sorption: the water is adsorbed on polyvinyl pyrrolidone over the whole composition range. [ABSTRACT FROM AUTHOR]

A correction to the article "Solvent effect on the complex formation of polyvinylpyrrolidone and polymonomethy itaconate" that was published in the March 1, 2013 issue is presented.

An investigation of the cometabolic degradation of thiophene in the presence of benzene has been performed in a continuous biofilm systemin order to study the kinetics of this conversion. The study showed result that thiophene interferes with the metabolism of benzene: benzene is not completely mineralised in the presence of thiophene. The micro-organisms are inactivated by thiophene, its metabolites or the metabolites of benzene. For low ratios of thiophene to benzene in the inlet of the reactor, the bacteria seem to adapt to thiophene and regain part of their activity that was lost when thiophene was introduced in the system. A hypothesis for this phenomena is that toxic metabolites of thiophene are converted biologically or abiotically into compounds, which are less harmful and inhibiting to the micro-organisms.Resting cells, which have been activated previously with benzene, are able to degrade thiophene, and this conversion leads to the inactivation or the death of the cells. [ABSTRACT FROM AUTHOR]