Air radon concentration decrease in a waste water treatment plant

(222)Rn is a naturally occurring gas created from the decay of (226)Ra. The long-term health risk of breathing radon is lung cancer. One particular place where indoor radon concentrations can exceed national guidelines is in wastewater treatment plants (WWTPs) where treatment processes may contribute to ambient airborne concentrations. The aim of this paper was to study the radon concentration decrease after the application of corrective measures in a Spanish WWTP. According to first measures, air radon concentration exceeded International Commission Radiologica1 Protection (ICRP) normative (recommends intervention between 400 and 1000 Bq m(-3)). Therefore, the WWTP improved mechanical forced ventilation to lower occupational exposure. This measure allowed to increase the administrative controls, since the limitation of workers access to the plant changed from 2 h d(-1) (considering a maximum permissible dose of 20 mSv y(-1) averaged over 5 y) to 7 h d(-1).

Hepatitis C virus reinfection among prisoners with sustained virological response after treatment for chronic hepatitis C

BACKGROUND & AIMS

We estimated HCV reinfection rate and its associated risk factors in inmates with chronic hepatitis C who had achieved sustained virological response (SVR) after completing combination therapy while in prison.

METHODS

Individuals who had achieved an SVR after treatment provided from January 2003 to December 2009 at four prisons in Catalonia, had been tested annually for HCV RNA and were in prison during 2010, were invited to complete a questionnaire regarding risk factors for reinfection. Incidence rate was calculated as 100 person-years of follow-up. Risk factors potentially associated with reinfection were evaluated by bivariate log-rank test and multivariate Cox regression analysis.

RESULTS

One hundred and nineteen subjects who had achieved an SVR agreed to participate. 98% were male, with a median age of 33.3 ± 6.3 years and 81% had a history of injection drug use (IDU). After a mean follow-up of 1.4 years, HCV reinfection was identified in nine former IDUs, seven with HCV genotype switch, for an overall reinfection rate of 5.27 cases per 100 person-years. Reinfection incidence was significantly higher among active drug users (HR=12.47; 95% CI: 2.90-53.71), HIV co-infected (HR=9.95; 95% CI: 1.73-57.34), and those engaging in more than one risk behaviors after treatment (HR=7.47; 95% CI: 1.19-46.89).

CONCLUSIONS

HCV reinfection among inmates after successful treatment is high especially in those with ongoing IDU. Preventative interventions at diagnosis and during and after HCV treatment should be strongly reinforced.

Health-related quality of life, patient satisfaction, and adherence to treatment in patients with moderate or severe atopic dermatitis on maintenance therapy: the CONDA-SAT study

OBJECTIVE

To evaluate health-related quality of life (HRQOL), patient satisfaction, and adherence to treatment in patients with moderate or severe atopic dermatitis on maintenance therapy.

MATERIAL AND METHODS

We performed a national, multicenter, cross-sectional, epidemiological study in adults and children with moderate or severe atopic dermatitis of at least 16 months' duration who were receiving maintenance therapy. We used the Dermatology Life Quality Index (DLQI), the children's version of this scale (cDLQI), and the Morisky medication adherence scale. Visual analog scales were used to measure treatment satisfaction. We used the Mann-Whitney U test to compare HRQOL between patients with moderate and severe disease and the Wilcoxon test to compare the frequency and duration of flares before and after the start of maintenance therapy.

RESULTS

We studied 141 children and 141 adults; the prevalence of moderate AD in these groups was 85.8% and 79.4%, respectively. The impact of AD on HRQOL was mild to moderate. Maintenance therapy led to a significant decrease in the frequency and duration of flares (P < .001). While treatment satisfaction was high in both groups, adherence was poor (18.4%-42.6% in children and 14.9%-27.0% in adults).

CONCLUSIONS

Patients with moderate and severe AD receiving maintenance therapy experience a reduction in the number and duration of flares and an improvement in HRQOL. While treatment satisfaction is high, adherence rates could be improved.

Performance of rural health clinics: an examination of efficiency and Medicare beneficiary outcomes

INTRODUCTION

In 2011, some 3800 Rural Health Clinics (RHCs) delivered primary care in underserved rural areas throughout the USA. To date, little research has been conducted to identify the variability in RHC performance. In an effort to address the knowledge gaps, a national, longitudinal study was conducted of a panel of 3565 RHCs. The goals of the study were to determine: (1) the relationship between two aspects of performance: efficiency and effectiveness; and (2) the factors that influence variation in RHC performance.

METHODS

A non-experimental study of RHC performance was conducted using 2 years of secondary data from multiple sources. A study panel of RHCs was formed. This panel was composed of all RHCs continuously in operation during the period 2006-2007. The study panel was divided into two subsets - one for the provider-based clinics; another for the independent clinics. The individual RHC was the unit of analysis throughout the study. Descriptive statistics were calculated for each subset. Bivariate analyses was conducted of the relationships between the clinic characteristics and the performance outcome measures, as well as the interrelationships between various clinic characteristics using χ², t-tests, Cramer's V, Pearson correlation, and Spearman correlation statistics. Next, using covariance structure analysis, the interrelationships were examined among the context (community or demographic factors), design (organizational structure and other mediating factors), and performance (efficiency and effectiveness) of RHCs. Three hypotheses were tested: (1) the effectiveness of RHCs is positively influenced by efficiency; (2) there is a reciprocal relationship between RHC efficiency and effectiveness; and (3) large RHCs are more efficient than small RHCs.

RESULTS

To test the hypotheses that effectiveness of RHCs is positively influenced by efficiency and that there is a reciprocal relationship between efficiency and effectiveness, two covariance structure models were developed and revised: one for independent and one for provider-based RHCs. However, the revised models were not supported by the data. To test the hypothesis that large RHCs are more efficient than small ones, two additional efficiency-based structural equation models were constructed (one for independent RHCs and another for provider-based RHCs). Both of these models were supported by the data (independent model: χ² = 13.8, df = 8, p = 0.088, relative χ² = 1.723, adjusted goodness of fit index [AGFI] = .981, root mean square error of approximation [RMSEA] = .034; provider-based model: χ² = 19.011, df = 8, p = 0.015, relative χ² = 2.376, AGFI = .978, RMSEA = .043).

CONCLUSION

This study examined the relationship between efficiency and effectiveness of RHCs. In addition, it identified several factors that influence the variation in RHC performance. The study has implications for optimizing RHC performance, providing quality services to rural populations, and enhancing the value of RHC data. The present is a critical time in the history of RHCs as they transition to meet the goals and expectations of the US health system reform. Additional research is needed to quantify and trend RHCs' contribution to the rural health delivery system in order to optimize their service to rural populations.

Assessment of Kalman filter bias-adjustment technique to improve the simulation of ground-level ozone over Spain

The CALIOPE air quality modelling system has been used to diagnose ground level O(3) concentration for the year 2004, over the Iberian Peninsula. We investigate the improvement in the simulation of daily O(3) maximum by the use of a post-processing such as the Kalman filter bias-adjustment technique. The Kalman filter bias-adjustment technique is a recursive algorithm to optimally estimate bias-adjustment terms from previous measurements and model results. The bias-adjustment technique improved the simulation of daily O(3) maximum for the entire year and the all the stations considered over the whole domain. The corrected simulation presents improvements in statistical indicators such as correlation, root mean square error, mean bias, and gross error. After the post-processing the exceedances of O(3) concentration limits, as established by the European Directive 2008/50/CE, are better reproduced and the uncertainty of the modelling system, as established by the European Directive 2008/50/CE, is reduced from 20% to 7.5%. Such uncertainty in the model results is under the established EU limit of the 50%. Significant improvements in the O(3) timing and amplitude of the daily cycle are also observed after the post-processing. The systematic improvements in the O(3) maximum simulations suggest that the Kalman filter post-processing method is a suitable technique to reproduce accurate estimate of ground-level O(3) concentration. With this study we evince that the adjusted O(3) concentrations obtained after the post-process of the results from the CALIOPE system are a reliable means for real near time O(3) forecasts.