The Experts below are selected from a list of 24414 Experts worldwide ranked by ideXlab platform

Amy Pruden - One of the best experts on this subject based on the ideXlab platform.

  • interactive effects of temperature organic carbon and Pipe Material on microbiota composition and legionella pneumophila in hot water plumbing systems
    Microbiome, 2017
    Co-Authors: Marc Edwards, Caitlin R Proctor, Dongjuan Dai, Amy Pruden
    Abstract:

    Several biotic and abiotic factors have been reported to influence the proliferation of microbes, including Legionella pneumophila, in hot water premise plumbing systems, but their combined effects have not been systematically evaluated. Here, we utilize simulated household water heaters to examine the effects of stepwise increases in temperature (32–53 °C), Pipe Material (copper vs. cross-linked polyethylene (PEX)), and influent assimilable organic carbon (0–700 μg/L) on opportunistic pathogen gene copy numbers and the microbiota composition, as determined by quantitative polymerase chain reaction and 16S rRNA gene amplicon sequencing. Temperature had an overarching influence on both the microbiota composition and L. pneumophila numbers. L. pneumophila peaked at 41 °C in the presence of PEX (1.58 × 105 gene copies/mL). At 53 °C, L. pneumophila was not detected. Several operational taxonomic units (OTUs) persisted across all conditions, accounting for 50% of the microbiota composition from 32 to 49 °C and 20% at 53 °C. Pipe Material most strongly influenced microbiota composition at lower temperatures, driven by five to six OTUs enriched with each Material. Copper Pipes supported less L. pneumophila than PEX Pipes (mean 2.5 log10 lower) at temperatures ≤ 41 °C, but showed no difference in total bacterial numbers. Differences between Pipe Materials diminished with elevated temperature, probably resulting from decreased release of copper ions. At temperatures ≤ 45 °C, influent assimilable organic carbon correlated well with total bacterial numbers, but not with L. pneumophila numbers. At 53 °C, PEX Pipes leached organic carbon, reducing the importance of dosed organic carbon. L. pneumophila numbers correlated with a Legionella OTU and a Methylophilus OTU identified by amplicon sequencing. Temperature was the most effective factor for the control of L. pneumophila, while microbiota composition shifted with each stepwise temperature increase. While copper Pipe may also help shape the microbiota composition and limit L. pneumophila proliferation, its benefits might be constrained at higher temperatures. Influent assimilable organic carbon affected total bacterial numbers, but had minimal influence on opportunistic pathogen gene numbers or microbiota composition. These findings provide guidance among multiple control measures for the growth of opportunistic pathogens in hot water plumbing and insight into the mediating role of microbial ecological factors.

  • Interactive effects of temperature, organic carbon, and Pipe Material on microbiota composition and Legionella pneumophila in hot water plumbing systems
    BMC, 2017
    Co-Authors: Caitlin R Proctor, Dongjuan Dai, Marc A. Edwards, Amy Pruden
    Abstract:

    Abstract Background Several biotic and abiotic factors have been reported to influence the proliferation of microbes, including Legionella pneumophila, in hot water premise plumbing systems, but their combined effects have not been systematically evaluated. Here, we utilize simulated household water heaters to examine the effects of stepwise increases in temperature (32–53 °C), Pipe Material (copper vs. cross-linked polyethylene (PEX)), and influent assimilable organic carbon (0–700 μg/L) on opportunistic pathogen gene copy numbers and the microbiota composition, as determined by quantitative polymerase chain reaction and 16S rRNA gene amplicon sequencing. Results Temperature had an overarching influence on both the microbiota composition and L. pneumophila numbers. L. pneumophila peaked at 41 °C in the presence of PEX (1.58 × 105 gene copies/mL). At 53 °C, L. pneumophila was not detected. Several operational taxonomic units (OTUs) persisted across all conditions, accounting for 50% of the microbiota composition from 32 to 49 °C and 20% at 53 °C. Pipe Material most strongly influenced microbiota composition at lower temperatures, driven by five to six OTUs enriched with each Material. Copper Pipes supported less L. pneumophila than PEX Pipes (mean 2.5 log10 lower) at temperatures ≤ 41 °C, but showed no difference in total bacterial numbers. Differences between Pipe Materials diminished with elevated temperature, probably resulting from decreased release of copper ions. At temperatures ≤ 45 °C, influent assimilable organic carbon correlated well with total bacterial numbers, but not with L. pneumophila numbers. At 53 °C, PEX Pipes leached organic carbon, reducing the importance of dosed organic carbon. L. pneumophila numbers correlated with a Legionella OTU and a Methylophilus OTU identified by amplicon sequencing. Conclusions Temperature was the most effective factor for the control of L. pneumophila, while microbiota composition shifted with each stepwise temperature increase. While copper Pipe may also help shape the microbiota composition and limit L. pneumophila proliferation, its benefits might be constrained at higher temperatures. Influent assimilable organic carbon affected total bacterial numbers, but had minimal influence on opportunistic pathogen gene numbers or microbiota composition. These findings provide guidance among multiple control measures for the growth of opportunistic pathogens in hot water plumbing and insight into the mediating role of microbial ecological factors

  • impact of water chemistry Pipe Material and stagnation on the building plumbing microbiome
    PLOS ONE, 2015
    Co-Authors: Jeffrey Parks, Marc Edwards, Amy Pruden
    Abstract:

    A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing). To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three Pipe Materials (copper with lead solder, CPVC with brass fittings or copper/lead combined Pipe) were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the Pipe rig, Pipe Material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO42- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9–10) had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

  • Effect of disinfectant, water age, and Pipe Materials on bacterial and eukaryotic community structure in drinking water biofilm.
    Environmental science & technology, 2014
    Co-Authors: Hong Wang, Marc Edwards, Sheldon Masters, Joseph O. Falkinham, Amy Pruden
    Abstract:

    Availability of safe, pathogen-free drinking water is vital to public health; however, it is impossible to deliver sterile drinking water to consumers. Recent microbiome research is bringing new understanding to the true extent and diversity of microbes that inhabit water distribution systems. The purpose of this study was to determine how water chemistry in main distribution lines shape the microbiome in drinking water biofilms and to explore potential associations between opportunistic pathogens and indigenous drinking water microbes. Effects of disinfectant (chloramines, chlorine), water age (2.3 days, 5.7 days), and Pipe Material (cement, iron, PVC) were compared in parallel triplicate simulated water distribution systems. Pyrosequencing was employed to characterize bacteria and terminal restriction fragment polymorphism was used to profile both bacteria and eukaryotes inhabiting Pipe biofilms. Disinfectant and water age were both observed to be strong factors in shaping bacterial and eukaryotic community structures. Pipe Material only influenced the bacterial community structure (ANOSIM test, P < 0.05). Interactive effects of disinfectant, Pipe Material, and water age on both bacteria and eukaryotes were noted. Disinfectant concentration had the strongest effect on bacteria, while dissolved oxygen appeared to be a major driver for eukaryotes (BEST test). Several correlations of similarity metrics among populations of bacteria, eukaryotes, and opportunistic pathogens, as well as one significant association between mycobacterial and proteobacterial operational taxonomic units, provides insight into means by which manipulating the microbiome may lead to new avenues for limiting the growth of opportunistic pathogens (e.g., Legionella) or other nuisance organisms (e.g., nitrifiers).

Rehan Jamil - One of the best experts on this subject based on the ideXlab platform.

  • Performance of a new Pipe Material UHMWPE against disinfectant decay in water distribution networks
    Clean Technologies and Environmental Policy, 2018
    Co-Authors: Rehan Jamil
    Abstract:

    The concentration of any disinfectant is a major parameter which is used to evaluate the quality of water. Chlorine is the most common disinfecting agent used during water treatment and its distribution through networks. In this study, the hydraulic simulation of chlorine decay is performed for an existing and operational mild steel (MS) Pipe network as well as a new Pipe Material ultra-high-molecular-weight poly-ethylene (UHMWPE) as an alternate for the purpose of comparing the water quality performance of both Materials. The results show that the initial chlorine concentration required to be added to the water tank to sustain a minimum allowable concentration in the network is found to be almost double for MS Pipe system as compared to UHMWPE. However, the decay pattern for MS Pipes is found to be irregular and varying whereas it is smooth and almost linear in nature for UHMWPE Pipe system. The research proves to be useful for selection of an economical and efficient Pipe Material.

Marc Edwards - One of the best experts on this subject based on the ideXlab platform.

  • interactive effects of temperature organic carbon and Pipe Material on microbiota composition and legionella pneumophila in hot water plumbing systems
    Microbiome, 2017
    Co-Authors: Marc Edwards, Caitlin R Proctor, Dongjuan Dai, Amy Pruden
    Abstract:

    Several biotic and abiotic factors have been reported to influence the proliferation of microbes, including Legionella pneumophila, in hot water premise plumbing systems, but their combined effects have not been systematically evaluated. Here, we utilize simulated household water heaters to examine the effects of stepwise increases in temperature (32–53 °C), Pipe Material (copper vs. cross-linked polyethylene (PEX)), and influent assimilable organic carbon (0–700 μg/L) on opportunistic pathogen gene copy numbers and the microbiota composition, as determined by quantitative polymerase chain reaction and 16S rRNA gene amplicon sequencing. Temperature had an overarching influence on both the microbiota composition and L. pneumophila numbers. L. pneumophila peaked at 41 °C in the presence of PEX (1.58 × 105 gene copies/mL). At 53 °C, L. pneumophila was not detected. Several operational taxonomic units (OTUs) persisted across all conditions, accounting for 50% of the microbiota composition from 32 to 49 °C and 20% at 53 °C. Pipe Material most strongly influenced microbiota composition at lower temperatures, driven by five to six OTUs enriched with each Material. Copper Pipes supported less L. pneumophila than PEX Pipes (mean 2.5 log10 lower) at temperatures ≤ 41 °C, but showed no difference in total bacterial numbers. Differences between Pipe Materials diminished with elevated temperature, probably resulting from decreased release of copper ions. At temperatures ≤ 45 °C, influent assimilable organic carbon correlated well with total bacterial numbers, but not with L. pneumophila numbers. At 53 °C, PEX Pipes leached organic carbon, reducing the importance of dosed organic carbon. L. pneumophila numbers correlated with a Legionella OTU and a Methylophilus OTU identified by amplicon sequencing. Temperature was the most effective factor for the control of L. pneumophila, while microbiota composition shifted with each stepwise temperature increase. While copper Pipe may also help shape the microbiota composition and limit L. pneumophila proliferation, its benefits might be constrained at higher temperatures. Influent assimilable organic carbon affected total bacterial numbers, but had minimal influence on opportunistic pathogen gene numbers or microbiota composition. These findings provide guidance among multiple control measures for the growth of opportunistic pathogens in hot water plumbing and insight into the mediating role of microbial ecological factors.

  • impact of water chemistry Pipe Material and stagnation on the building plumbing microbiome
    PLOS ONE, 2015
    Co-Authors: Jeffrey Parks, Marc Edwards, Amy Pruden
    Abstract:

    A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing). To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three Pipe Materials (copper with lead solder, CPVC with brass fittings or copper/lead combined Pipe) were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the Pipe rig, Pipe Material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO42- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9–10) had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

  • Effect of disinfectant, water age, and Pipe Materials on bacterial and eukaryotic community structure in drinking water biofilm.
    Environmental science & technology, 2014
    Co-Authors: Hong Wang, Marc Edwards, Sheldon Masters, Joseph O. Falkinham, Amy Pruden
    Abstract:

    Availability of safe, pathogen-free drinking water is vital to public health; however, it is impossible to deliver sterile drinking water to consumers. Recent microbiome research is bringing new understanding to the true extent and diversity of microbes that inhabit water distribution systems. The purpose of this study was to determine how water chemistry in main distribution lines shape the microbiome in drinking water biofilms and to explore potential associations between opportunistic pathogens and indigenous drinking water microbes. Effects of disinfectant (chloramines, chlorine), water age (2.3 days, 5.7 days), and Pipe Material (cement, iron, PVC) were compared in parallel triplicate simulated water distribution systems. Pyrosequencing was employed to characterize bacteria and terminal restriction fragment polymorphism was used to profile both bacteria and eukaryotes inhabiting Pipe biofilms. Disinfectant and water age were both observed to be strong factors in shaping bacterial and eukaryotic community structures. Pipe Material only influenced the bacterial community structure (ANOSIM test, P < 0.05). Interactive effects of disinfectant, Pipe Material, and water age on both bacteria and eukaryotes were noted. Disinfectant concentration had the strongest effect on bacteria, while dissolved oxygen appeared to be a major driver for eukaryotes (BEST test). Several correlations of similarity metrics among populations of bacteria, eukaryotes, and opportunistic pathogens, as well as one significant association between mycobacterial and proteobacterial operational taxonomic units, provides insight into means by which manipulating the microbiome may lead to new avenues for limiting the growth of opportunistic pathogens (e.g., Legionella) or other nuisance organisms (e.g., nitrifiers).

Caitlin R Proctor - One of the best experts on this subject based on the ideXlab platform.

  • interactive effects of temperature organic carbon and Pipe Material on microbiota composition and legionella pneumophila in hot water plumbing systems
    Microbiome, 2017
    Co-Authors: Marc Edwards, Caitlin R Proctor, Dongjuan Dai, Amy Pruden
    Abstract:

    Several biotic and abiotic factors have been reported to influence the proliferation of microbes, including Legionella pneumophila, in hot water premise plumbing systems, but their combined effects have not been systematically evaluated. Here, we utilize simulated household water heaters to examine the effects of stepwise increases in temperature (32–53 °C), Pipe Material (copper vs. cross-linked polyethylene (PEX)), and influent assimilable organic carbon (0–700 μg/L) on opportunistic pathogen gene copy numbers and the microbiota composition, as determined by quantitative polymerase chain reaction and 16S rRNA gene amplicon sequencing. Temperature had an overarching influence on both the microbiota composition and L. pneumophila numbers. L. pneumophila peaked at 41 °C in the presence of PEX (1.58 × 105 gene copies/mL). At 53 °C, L. pneumophila was not detected. Several operational taxonomic units (OTUs) persisted across all conditions, accounting for 50% of the microbiota composition from 32 to 49 °C and 20% at 53 °C. Pipe Material most strongly influenced microbiota composition at lower temperatures, driven by five to six OTUs enriched with each Material. Copper Pipes supported less L. pneumophila than PEX Pipes (mean 2.5 log10 lower) at temperatures ≤ 41 °C, but showed no difference in total bacterial numbers. Differences between Pipe Materials diminished with elevated temperature, probably resulting from decreased release of copper ions. At temperatures ≤ 45 °C, influent assimilable organic carbon correlated well with total bacterial numbers, but not with L. pneumophila numbers. At 53 °C, PEX Pipes leached organic carbon, reducing the importance of dosed organic carbon. L. pneumophila numbers correlated with a Legionella OTU and a Methylophilus OTU identified by amplicon sequencing. Temperature was the most effective factor for the control of L. pneumophila, while microbiota composition shifted with each stepwise temperature increase. While copper Pipe may also help shape the microbiota composition and limit L. pneumophila proliferation, its benefits might be constrained at higher temperatures. Influent assimilable organic carbon affected total bacterial numbers, but had minimal influence on opportunistic pathogen gene numbers or microbiota composition. These findings provide guidance among multiple control measures for the growth of opportunistic pathogens in hot water plumbing and insight into the mediating role of microbial ecological factors.

  • Interactive effects of temperature, organic carbon, and Pipe Material on microbiota composition and Legionella pneumophila in hot water plumbing systems
    BMC, 2017
    Co-Authors: Caitlin R Proctor, Dongjuan Dai, Marc A. Edwards, Amy Pruden
    Abstract:

    Abstract Background Several biotic and abiotic factors have been reported to influence the proliferation of microbes, including Legionella pneumophila, in hot water premise plumbing systems, but their combined effects have not been systematically evaluated. Here, we utilize simulated household water heaters to examine the effects of stepwise increases in temperature (32–53 °C), Pipe Material (copper vs. cross-linked polyethylene (PEX)), and influent assimilable organic carbon (0–700 μg/L) on opportunistic pathogen gene copy numbers and the microbiota composition, as determined by quantitative polymerase chain reaction and 16S rRNA gene amplicon sequencing. Results Temperature had an overarching influence on both the microbiota composition and L. pneumophila numbers. L. pneumophila peaked at 41 °C in the presence of PEX (1.58 × 105 gene copies/mL). At 53 °C, L. pneumophila was not detected. Several operational taxonomic units (OTUs) persisted across all conditions, accounting for 50% of the microbiota composition from 32 to 49 °C and 20% at 53 °C. Pipe Material most strongly influenced microbiota composition at lower temperatures, driven by five to six OTUs enriched with each Material. Copper Pipes supported less L. pneumophila than PEX Pipes (mean 2.5 log10 lower) at temperatures ≤ 41 °C, but showed no difference in total bacterial numbers. Differences between Pipe Materials diminished with elevated temperature, probably resulting from decreased release of copper ions. At temperatures ≤ 45 °C, influent assimilable organic carbon correlated well with total bacterial numbers, but not with L. pneumophila numbers. At 53 °C, PEX Pipes leached organic carbon, reducing the importance of dosed organic carbon. L. pneumophila numbers correlated with a Legionella OTU and a Methylophilus OTU identified by amplicon sequencing. Conclusions Temperature was the most effective factor for the control of L. pneumophila, while microbiota composition shifted with each stepwise temperature increase. While copper Pipe may also help shape the microbiota composition and limit L. pneumophila proliferation, its benefits might be constrained at higher temperatures. Influent assimilable organic carbon affected total bacterial numbers, but had minimal influence on opportunistic pathogen gene numbers or microbiota composition. These findings provide guidance among multiple control measures for the growth of opportunistic pathogens in hot water plumbing and insight into the mediating role of microbial ecological factors

Ma You-yi - One of the best experts on this subject based on the ideXlab platform.

  • Application of municipal sewerage Pipe Material in small towns
    Journal of Water Resources and Water Engineering, 2011
    Co-Authors: Ma You-yi
    Abstract:

    Small towns in our country have developed very fast at present.The infrastructural construction of small towns developed fast too.The rational selection of Pipe Material is particularly important to the plan and design of sewerage engineering in small towns.But the phenomenon of applying mechanically blindly the Pipe Material types of large and medium cities exists widely when the sewerage engineering is constructed in small towns,witch causes the inconsequence of design and construction.The article analyzed the characteristics and applicability of different sewerage Pipes in small towns,and recommended high-quality sewerage Pipe Materials in accordance with the Pipe network characteristic of small towns.

  • Application of Municipal Water Supply Pipe Material into Small Towns
    Journal of Water Resources and Water Engineering, 2009
    Co-Authors: Ma You-yi
    Abstract:

    Small towns in our country have been constructed fast at present.In order to construct and develop small towns,the infrastructural construction should be reinforced.The rational selection of Pipe Material is particularly important in planning and design of the water supply engineering in small towns.But the phenomenon of applying blindly the Pipe Material types in large and medium cities exists widely when the water supply engineering is constructed in small towns.So that causes the inconsequence of design and construction.Characteristics and applicability in small towns of different municipal water supply Pipes are analyzed,and high-quality water supply Pipe Materials that are according with the Pipe network characteristic of small towns are recommended.