116 research outputs found

    Field Studies and Modeling Exploring Mean and Maximum Water Age Association to Water Quality in a Drinking Water Distribution Network

    Get PDF
    This paper presents the findings of an investigation into predicted/modeled water age and the associated quality characteristics within a UK drinking water distribution network to determine if there is a discernable link. The hydraulic and water quality software Aquis was used to identify water volumes of different ages, generated by localized demand patterns in pipes that are in close proximity to one another. The pipe network studied was small spatially, of a single material, and had a consistent demand attributable to serving predominately light industry, but with interesting hydraulic patterns involving loops and mixing of water volumes, and some long retention times. Field work was undertaken to obtain water quality samples from five network locations identified as containing a broad range of calculated water age. The samples were analyzed for standard regulated parameters by a UK Accreditation Service (UKAS) [formerly known as the National Measurement Accreditation Service (NAMAS)] accredited water laboratory in line with UK water industry standard quality assurance practice. The water sample analytical results were examined to test how a number of physical, chemical, and bacteriological parameters related to the calculated water age at each sample point. Heterotrophic plate counts were used as the indicator of general bacteriological water quality. A limited association between the calculated water mean age and quality parameters was observed. Further investigations, taking into account mixing of different aged water volumes and the maximum age contributions to the mean age at each sample location, produced some association. The work demonstrated that mean age is not a sufficient guide to general water quality in this small network area. Mixing effects, and maximum age volume contributions, need to be taken into account if a more comprehensive understanding of water quality is to be obtained

    Online modelling of water distribution systems: a UK case study

    Get PDF
    Hydraulic simulation models of water distribution networks are routinely used for operational investigations and network design purposes. However, their full potential is often never realised because, in the majority of cases, they have been calibrated with data collected manually from the field during a single historic time period and, as such, reflect the network operational conditions that were prevalent at that time, and they are then applied as part of a reactive, desktop investigation. In order to use a hydraulic model to assist proactive distribution network management its element asset information must be up to date and it should be able to access current network information to drive simulations. Historically this advance has been restricted by the high cost of collecting and transferring the necessary field measurements. However, recent innovation and cost reductions associated with data transfer is resulting in collection of data from increasing numbers of sensors in water supply systems, and automatic transfer of the data to point of use. This means engineers potentially have access to a constant stream of current network data that enables a new era of "on-line" modelling that can be used to continually assess standards of service compliance for pressure and reduce the impact of network events, such as mains bursts, on customers. A case study is presented here that shows how an online modelling system can give timely warning of changes from normal network operation, providing capacity to minimise customer impact

    Comparative study on seasonal variation in hydro-chemical parameters of Ganga River water using comprehensive pollution index (CPI) at Rishikesh (Uttarakhand) India

    Get PDF
    The assessment of the Ganga River System at Rishikesh was investigated at five different sites for three different seasons (summer, winter and monsoon) using comprehensive pollution index (CPI), considering 10 physicochemical parameters such as conductivity, turbidity, total dissolved solids, dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, total hardness, Cl, phosphate and sulphate. The CPI was found to be 0.54–2.47, which indicates the variation in pollution level of the River Ganga. The variation in pollution index value clearly shows that water quality was slightly polluted in winter (0.54–0.72) and summer (0.64–0.88) whereas high contamination (1.68–2.47) was observed during monsoon season. Among various sampling stations, Pashulok Barrage (Site 5) was more contaminated than other sites. All the studied parameters were under the permissible limit of W.H.O. (2011) except turbidity, total solids and suspended solids which were higher than the permissible limit. This study also illustrates the correlation between parameters by developing correlation matrix. The result of this study clearly elucidates that the water quality is getting contaminated as we moved from upstream to downstream of river and helps to understand the potential effects of water quality on drinking, irrigation and other purposes

    Socioeconomic position, lifestyle habits and biomarkers of epigenetic aging: A multi-cohort analysis

    Get PDF
    Differences in health status by socioeconomic position (SEP) tend to be more evident at older ages, suggesting the involvement of a biological mechanism responsive to the accumulation of deleterious exposures across the lifespan. DNA methylation (DNAm) has been proposed as a biomarker of biological aging that conserves memory of endogenous and exogenous stress during life. We examined the association of education level, as an indicator of SEP, and lifestyle-related variables with four biomarkers of age-dependent DNAm dysregulation: the total number of stochastic epigenetic mutations (SEMs) and three epigenetic clocks (Horvath, Hannum and Levine), in 18 cohorts spanning 12 countries. The four biological aging biomarkers were associated with education and different sets of risk factors independently, and the magnitude of the effects differed depending on the biomarker and the predictor. On average, the effect of low education on epigenetic aging was comparable with those of other lifestyle-related risk factors (obesity, alcohol intake), with the exception of smoking, which had a significantly stronger effect. Our study shows that low education is an independent predictor of accelerated biological (epigenetic) aging and that epigenetic clocks appear to be good candidates for disentangling the biological pathways underlying social inequalities in healthy aging and longevity

    Socioeconomic position, lifestyle habits and biomarkers of epigenetic aging: A multi-cohort analysis

    Get PDF
    Differences in health status by socioeconomic position (SEP) tend to be more evident at older ages, suggesting the involvement of a biological mechanism responsive to the accumulation of deleterious exposures across the lifespan. DNA methylation (DNAm) has been proposed as a biomarker of biological aging that conserves memory of endogenous and exogenous stress during life.We examined the association of education level, as an indicator of SEP, and lifestyle-related variables with four biomarkers of age-dependent DNAm dysregulation: the total number of stochastic epigenetic mutations (SEMs) and three epigenetic clocks (Horvath, Hannum and Levine), in 18 cohorts spanning 12 countries.The four biological aging biomarkers were associated with education and different sets of risk factors independently, and the magnitude of the effects differed depending on the biomarker and the predictor. On average, the effect of low education on epigenetic aging was comparable with those of other lifestyle-related risk factors (obesity, alcohol intake), with the exception of smoking, which had a significantly stronger effect.Our study shows that low education is an independent predictor of accelerated biological (epigenetic) aging and that epigenetic clocks appear to be good candidates for disentangling the biological pathways underlying social inequalities in healthy aging and longevity

    Socioeconomic position, lifestyle habits and biomarkers of epigenetic aging: A multi-cohort analysis

    Get PDF
    Differences in health status by socioeconomic position (SEP) tend to be more evident at older ages, suggesting the involvement of a biological mechanism responsive to the accumulation of deleterious exposures across the lifespan. DNA methylation (DNAm) has been proposed as a biomarker of biological aging that conserves memory of endogenous and exogenous stress during life. We examined the association of education level, as an indicator of SEP, and lifestyle-related variables with four biomarkers of age-dependent DNAm dysregulation: the total number of stochastic epigenetic mutations (SEMs) and three epigenetic clocks (Horvath, Hannum and Levine), in 18 cohorts spanning 12 countries. The four biological aging biomarkers were associated with education and different sets of risk factors independently, and the magnitude of the effects differed depending on the biomarker and the predictor. On average, the effect of low education on epigenetic aging was comparable with those of other lifestyle-related risk factors (obesity, alcohol intake), with the exception of smoking, which had a significantly stronger effect. Our study shows that low education is an independent predictor of accelerated biological (epigenetic) aging and that epigenetic clocks appear to be good candidates for disentangling the biological pathways underlying social inequalities in healthy aging and longevity
    corecore