In this study, qPCR was used to quantify opportunistic premise plumbing pathogens(OPPPs) and free-living amoebae in 11 tap water samples collected over four seasons from a city in northern China. Results demonstrated ...In this study, qPCR was used to quantify opportunistic premise plumbing pathogens(OPPPs) and free-living amoebae in 11 tap water samples collected over four seasons from a city in northern China. Results demonstrated that the average numbers of gene copies of Legionella spp. and Mycobacterium spp. were significantly higher than those of Aeromonas spp.(p < 0.05). Legionella spp. and Mycobacterium spp. were 100%(44/44) positively detected while P. aeruginosa and Aeromonas spp. were 79.54%(35/44) and 77.27%(34/44) positively detected. Legionella pneumophila was only detected in 4 samples(4/44), demonstrating its occasional occurrence. No Mycobacterium avium or Naegleria fowleri was detected in any of the samples. The average gene copy numbers of target OPPPs were the highest in summer,suggesting seasonal prevalence of OPPPs. Average gene copy numbers of OPPPs in the taps of low-use-frequency were higher than in taps of high-use-frequency, but the difference was not significant for some OPPPs(p > 0.05). Moderate negative correlations between the chlorine concentration and the gene copy numbers of OPPPs were observed by Spearman analysis(rsranged from -0.311 to -0.710, p < 0.05). However, no significant correlations existed between OPPPs and AOC, BDOC, or turbidity. Moderate positive correlations were observed between the target microorganisms, especially for Acanthamoeba spp., through Spearman analysis(p < 0.05). Based on our studies, it is proposed that disinfectant concentration, season, taps with different-use frequency, OPPP species, and potential microbial correlations should be considered for control of OPPPs in tap water.展开更多
Seafloor and buried reliefs occur along continental margin of the Ross Sea(Antarctica).These features are several kilometres wide and tens of metres high,exhibiting cone or flat-top dome shapes.Previous studies have p...Seafloor and buried reliefs occur along continental margin of the Ross Sea(Antarctica).These features are several kilometres wide and tens of metres high,exhibiting cone or flat-top dome shapes.Previous studies have proposed a volcanic or glacial origin for these formations,but these hypotheses do not account for all the available evidence.In this study,we use morpho-bathymetric data,intermediate resolution multichannel seismic and high resolution chirp profiles,as well as magnetic lines to investigate these clusters of mounds.By employing targeted processing techniques to enhance the geophysical characterization of the seafloor and buried reliefs,and to understand the underlying geological features,we propose that the reliefs are mud volcanoes.Some of these formations appear to be associated with a plumbing system,as indicated by acoustic anomalies linked to sediment containing gas.These formations are likely fed by clayey source rocks of Miocene age.Additionally,other reliefs might be the result of mud mobilisation caused by gravity instability and fluid overpressure.展开更多
Changbaishan,an intraplate volcano,is characterized by an approximately 6 km wide summit caldera and last erupted in 1903.Changbaishan experienced a period of unrest between 2002 and 2006.The activity developed in thr...Changbaishan,an intraplate volcano,is characterized by an approximately 6 km wide summit caldera and last erupted in 1903.Changbaishan experienced a period of unrest between 2002 and 2006.The activity developed in three main stages,including shield volcano(basalts),cone-construction(trachyandesites to trachytes with minor basalts),and caldera-forming stages(trachytes to comendites).This last stage is associated with one of the more energetic eruptions of the last millennium on Earth,the 946 CE,VEI 7 Millennium Eruption(ME),which emitted over 100 km^(3) of pyroclastics.Compared to other active calderas,the plumbing system of Changbaishan and its evolution mechanisms remain poorly constrained.Here,we merge new whole-rock,glass,mineral,isotopic,and geobarometry data with geophysical data and present a model of the plumbing system.The results show that the volcano is characterized by at least three main magma reservoirs at different depths:a basaltic reservoir at the Moho/lower crust depth,an intermediate reservoir at 10-15 km depth,and a shallower reservoir at 0.5-3 km depth.The shallower reservoir was involved in the ME eruption,which was triggered by a fresh trachytic melt entering a shallower reservoir where a comenditic magma was stored.The trachytes and comendites originate from fractional crystallization processes and minor assimilation of upper crust material,while the less evolved melts assimilate lower crust material.Syn-eruptive magma mingling occurred during the ME eruption phase.The magma reservoirs of the caldera-forming stage partly reactivate those of the cone-construction stage.The depth of the magma storage zones is controlled by the layering of the crust.The plumbing system of Changbaishan is vertically extensive,with crystal mush reservoirs renewed by the replenishment of new trachytic to trachyandesitic magma from depth.Unlike other volcanoes,evidence of a basaltic recharge is lacking.The interpretation of the signals preceding possible future eruptions should consider the multi-level nature of t展开更多
The opening and spreading of the Atlantic Ocean between Africa and South America evolved during the Early Cretaceous and were preceded by dramatic tholeiitic(mafic)magmatism and minor silicic and alkaline volcanism.Th...The opening and spreading of the Atlantic Ocean between Africa and South America evolved during the Early Cretaceous and were preceded by dramatic tholeiitic(mafic)magmatism and minor silicic and alkaline volcanism.These features are presently recognized from the equatorial regions of Brazil and Africa to the Falklands and South Africa.In southeastern South America,continental flood basalts and related plumbing systems constitute the ParanáMagmatic Province(PMP),whose African counterpart is the Etendeka Magmatic Province(EMP).In northeastern Brazil,dike swarms and sill complexes compose the Equatorial Atlantic Magmatic Province(EQUAMP).As a common feature,these provinces are chemically represented by two prevalent magma types:(1)tholeiitic basalts and basaltic andesites with lowTi(TiO_(2)<~2 wt.%),also including transitional Ti tholeiites with TiO_(2)~2.7-1.7 wt.%,and low incompatible element contents.This type is predominantly found in the southern PMP and EMP,with minor occurrences in the EQUAMP.(2)Tholeiitic basalts and basaltic andesites with high Ti(TiO_(2)>~2 wt.%)and incompatible element contents.High Ti tholeiites are relevant in the northern PMP and EMP,and dominant in EQUAMP.Evolved rocks(SiO_(2)=57-65 wt.%)interpreted as byproducts of assimilation and/or fractional crystallization(AFC)processes from high Ti tholeiitic magmas,are scarce(but present)in all three provinces.An accurate analysis of multivariable databases collected from the literature for dikes and sills,including major and trace element and radiogenic isotope data,reveals close similarities in their geochemical signatures.In a paleogeographic reconstruction of West Gondwana,the intrusive remnants of the PMP,EMP and EQUAMP are spread over an area of nearly 10×10^(6)km^(2).forming perhaps the most extensive set of plumbing systems on Earth,with a relatively consistent chronology based on a vast collection of K-Ar and^(40)Ar/^(39)Ar data available in the literature.This work provides the first comprehensive data comparison to support the ex展开更多
The detailed structures of the volcanic edifice and plumbing system of the early Permian Tarim flood basalt were investigated by three-dimensional seismic imaging. The images show that the Tarim flood basalt erupted f...The detailed structures of the volcanic edifice and plumbing system of the early Permian Tarim flood basalt were investigated by three-dimensional seismic imaging. The images show that the Tarim flood basalt erupted from central volcanoes distributed along major faults. The uppermost magma formed a single lava lobe with a volume of *0.74 km3 and an aspect ratio of 50,implying a sheet flow eruption with a high effusion rate. At the subsurface level, all central volcanoes, irrespective of size, had a separate pipe-like feeder vent. Only thirteen dikes were identified at shallow depths of \100 m below the lava surface; deeper dikes were even rarer. The pipelike plumbing system and the paucity of dilational dikes were different from the typical plumbing system of flood basalt provinces on Earth, which are normally buoyancycontrolled dike–sill networks. A gas-driven vigorous eruption can be inferred from the imaged structure, which means that the Tarim flood basalt may have carried and released a large proportion of volcanic gas, similar to some mafic volcaniclastic deposit-bearing continental flood basalt provinces.展开更多
The modern field of Forensic Engineering evaluates the origin, cause, and duration of failed building components. As many failed components are subject to insurance claims and legal probes, a scientific methodology fo...The modern field of Forensic Engineering evaluates the origin, cause, and duration of failed building components. As many failed components are subject to insurance claims and legal probes, a scientific methodology for evaluating such events is inherently valuable. Due to the potential for widespread interior finish damage, failed plumbing supply components are commonly encountered during forensic evaluations. Plumbing pipes?themselves and properly soldered fittings rarely fail. Consequently, many failures correspond to mechanical fittings which form connections from pipes to plumbing fixtures.?The results of this study provide a scientific methodology to evaluate the duration of connection leaks by quantifying the extent of corrosion, patina, and accumulated deposits on various components?by creating and evaluating slow plumbing supply component connection leaks.展开更多
Drinking water quality deteriorates from treatment plant to customer taps, especially in the plumbing system. There is no direct evidence about what the differences are contributed by plumbing system. This study compa...Drinking water quality deteriorates from treatment plant to customer taps, especially in the plumbing system. There is no direct evidence about what the differences are contributed by plumbing system. This study compared the water quality in the water main and at customer tap by preparing a sampling tap on the water main. The biomass was quantified by adenosine triphosphate(ATP) and the microbial community was profiled by 454 pyrosequencing.The results showed that in distribution pipes, biofilm contributed >94% of the total biomass,while loose deposits showed little contribution(< 2%) because of the low amount of loose deposits. The distribution of biological stable water had minor effects on the microbiocidal water quality regarding both quantity(ATP 1 ng/L vs. 1.7 ng/L) and community of the bacteria. Whereas the plumbing system has significant contribution to the increase of active biomass(1.7 ng/L vs. 2.9 ng/L) and the changes of bacterial community. The relative abundance of Sphingomonas spp. at tap(22%) was higher than that at water main(2%), while the relative abundance of Pseudomonas spp. in tap water(15%) was lower than that in the water from street water main(29%). Though only one location was prepared and studied, the present study showed that the protocol of making sampling tap on water main offered directly evidences about the impacts of plumbing system on tap water quality, which makes it possible to distinguish and study the processes in distribution system and plumbing system separately.展开更多
基金supported by the National Key Research and Development Plan(No.2016YFA0203200)the National Natural Science Foundation of China(No.51538013)the project of Chinese Academy of Sciences(No.QYZDY-SSW-DQC004)
文摘In this study, qPCR was used to quantify opportunistic premise plumbing pathogens(OPPPs) and free-living amoebae in 11 tap water samples collected over four seasons from a city in northern China. Results demonstrated that the average numbers of gene copies of Legionella spp. and Mycobacterium spp. were significantly higher than those of Aeromonas spp.(p < 0.05). Legionella spp. and Mycobacterium spp. were 100%(44/44) positively detected while P. aeruginosa and Aeromonas spp. were 79.54%(35/44) and 77.27%(34/44) positively detected. Legionella pneumophila was only detected in 4 samples(4/44), demonstrating its occasional occurrence. No Mycobacterium avium or Naegleria fowleri was detected in any of the samples. The average gene copy numbers of target OPPPs were the highest in summer,suggesting seasonal prevalence of OPPPs. Average gene copy numbers of OPPPs in the taps of low-use-frequency were higher than in taps of high-use-frequency, but the difference was not significant for some OPPPs(p > 0.05). Moderate negative correlations between the chlorine concentration and the gene copy numbers of OPPPs were observed by Spearman analysis(rsranged from -0.311 to -0.710, p < 0.05). However, no significant correlations existed between OPPPs and AOC, BDOC, or turbidity. Moderate positive correlations were observed between the target microorganisms, especially for Acanthamoeba spp., through Spearman analysis(p < 0.05). Based on our studies, it is proposed that disinfectant concentration, season, taps with different-use frequency, OPPP species, and potential microbial correlations should be considered for control of OPPPs in tap water.
文摘Seafloor and buried reliefs occur along continental margin of the Ross Sea(Antarctica).These features are several kilometres wide and tens of metres high,exhibiting cone or flat-top dome shapes.Previous studies have proposed a volcanic or glacial origin for these formations,but these hypotheses do not account for all the available evidence.In this study,we use morpho-bathymetric data,intermediate resolution multichannel seismic and high resolution chirp profiles,as well as magnetic lines to investigate these clusters of mounds.By employing targeted processing techniques to enhance the geophysical characterization of the seafloor and buried reliefs,and to understand the underlying geological features,we propose that the reliefs are mud volcanoes.Some of these formations appear to be associated with a plumbing system,as indicated by acoustic anomalies linked to sediment containing gas.These formations are likely fed by clayey source rocks of Miocene age.Additionally,other reliefs might be the result of mud mobilisation caused by gravity instability and fluid overpressure.
基金funded by the National Natural Science Foundation of China under Grant Nos.41972313 and 41790453by the Engineering Research Center of Geothermal Resources Development Technology and Equipment,Ministry of Education,Jilin University,China.
文摘Changbaishan,an intraplate volcano,is characterized by an approximately 6 km wide summit caldera and last erupted in 1903.Changbaishan experienced a period of unrest between 2002 and 2006.The activity developed in three main stages,including shield volcano(basalts),cone-construction(trachyandesites to trachytes with minor basalts),and caldera-forming stages(trachytes to comendites).This last stage is associated with one of the more energetic eruptions of the last millennium on Earth,the 946 CE,VEI 7 Millennium Eruption(ME),which emitted over 100 km^(3) of pyroclastics.Compared to other active calderas,the plumbing system of Changbaishan and its evolution mechanisms remain poorly constrained.Here,we merge new whole-rock,glass,mineral,isotopic,and geobarometry data with geophysical data and present a model of the plumbing system.The results show that the volcano is characterized by at least three main magma reservoirs at different depths:a basaltic reservoir at the Moho/lower crust depth,an intermediate reservoir at 10-15 km depth,and a shallower reservoir at 0.5-3 km depth.The shallower reservoir was involved in the ME eruption,which was triggered by a fresh trachytic melt entering a shallower reservoir where a comenditic magma was stored.The trachytes and comendites originate from fractional crystallization processes and minor assimilation of upper crust material,while the less evolved melts assimilate lower crust material.Syn-eruptive magma mingling occurred during the ME eruption phase.The magma reservoirs of the caldera-forming stage partly reactivate those of the cone-construction stage.The depth of the magma storage zones is controlled by the layering of the crust.The plumbing system of Changbaishan is vertically extensive,with crystal mush reservoirs renewed by the replenishment of new trachytic to trachyandesitic magma from depth.Unlike other volcanoes,evidence of a basaltic recharge is lacking.The interpretation of the signals preceding possible future eruptions should consider the multi-level nature of t
基金the Brailian agencies FAPESP(2017/13130-0)CAPES(1643026)for the PhD scholarships at the USP+4 种基金the Research Internships Abroad Program(BEPE/FAPESP)for the scholarship at the UQ(2018/24769-5)the CNPq for the research fellowship(303201/2019-3)PhD scholarship(141413/2018-2)MSc scholarship(132996/2019-7)at USP,respectivelythe sandwich PhD scholarship at the UQ(88881.188664/2018-01).
文摘The opening and spreading of the Atlantic Ocean between Africa and South America evolved during the Early Cretaceous and were preceded by dramatic tholeiitic(mafic)magmatism and minor silicic and alkaline volcanism.These features are presently recognized from the equatorial regions of Brazil and Africa to the Falklands and South Africa.In southeastern South America,continental flood basalts and related plumbing systems constitute the ParanáMagmatic Province(PMP),whose African counterpart is the Etendeka Magmatic Province(EMP).In northeastern Brazil,dike swarms and sill complexes compose the Equatorial Atlantic Magmatic Province(EQUAMP).As a common feature,these provinces are chemically represented by two prevalent magma types:(1)tholeiitic basalts and basaltic andesites with lowTi(TiO_(2)<~2 wt.%),also including transitional Ti tholeiites with TiO_(2)~2.7-1.7 wt.%,and low incompatible element contents.This type is predominantly found in the southern PMP and EMP,with minor occurrences in the EQUAMP.(2)Tholeiitic basalts and basaltic andesites with high Ti(TiO_(2)>~2 wt.%)and incompatible element contents.High Ti tholeiites are relevant in the northern PMP and EMP,and dominant in EQUAMP.Evolved rocks(SiO_(2)=57-65 wt.%)interpreted as byproducts of assimilation and/or fractional crystallization(AFC)processes from high Ti tholeiitic magmas,are scarce(but present)in all three provinces.An accurate analysis of multivariable databases collected from the literature for dikes and sills,including major and trace element and radiogenic isotope data,reveals close similarities in their geochemical signatures.In a paleogeographic reconstruction of West Gondwana,the intrusive remnants of the PMP,EMP and EQUAMP are spread over an area of nearly 10×10^(6)km^(2).forming perhaps the most extensive set of plumbing systems on Earth,with a relatively consistent chronology based on a vast collection of K-Ar and^(40)Ar/^(39)Ar data available in the literature.This work provides the first comprehensive data comparison to support the ex
基金supported by the National Basic Research Program of China(2010CB808906)the National Natural Science Foundation of China(41272368)to WT
文摘The detailed structures of the volcanic edifice and plumbing system of the early Permian Tarim flood basalt were investigated by three-dimensional seismic imaging. The images show that the Tarim flood basalt erupted from central volcanoes distributed along major faults. The uppermost magma formed a single lava lobe with a volume of *0.74 km3 and an aspect ratio of 50,implying a sheet flow eruption with a high effusion rate. At the subsurface level, all central volcanoes, irrespective of size, had a separate pipe-like feeder vent. Only thirteen dikes were identified at shallow depths of \100 m below the lava surface; deeper dikes were even rarer. The pipelike plumbing system and the paucity of dilational dikes were different from the typical plumbing system of flood basalt provinces on Earth, which are normally buoyancycontrolled dike–sill networks. A gas-driven vigorous eruption can be inferred from the imaged structure, which means that the Tarim flood basalt may have carried and released a large proportion of volcanic gas, similar to some mafic volcaniclastic deposit-bearing continental flood basalt provinces.
文摘The modern field of Forensic Engineering evaluates the origin, cause, and duration of failed building components. As many failed components are subject to insurance claims and legal probes, a scientific methodology for evaluating such events is inherently valuable. Due to the potential for widespread interior finish damage, failed plumbing supply components are commonly encountered during forensic evaluations. Plumbing pipes?themselves and properly soldered fittings rarely fail. Consequently, many failures correspond to mechanical fittings which form connections from pipes to plumbing fixtures.?The results of this study provide a scientific methodology to evaluate the duration of connection leaks by quantifying the extent of corrosion, patina, and accumulated deposits on various components?by creating and evaluating slow plumbing supply component connection leaks.
基金the support from the National Key R&D program of China(No.2018YFE0204100)the National Natural Science Foundation of China(No.52022103)the National Natural Science Foundation of China for International Cooperation and Exchange(No.51820105011)。
文摘Drinking water quality deteriorates from treatment plant to customer taps, especially in the plumbing system. There is no direct evidence about what the differences are contributed by plumbing system. This study compared the water quality in the water main and at customer tap by preparing a sampling tap on the water main. The biomass was quantified by adenosine triphosphate(ATP) and the microbial community was profiled by 454 pyrosequencing.The results showed that in distribution pipes, biofilm contributed >94% of the total biomass,while loose deposits showed little contribution(< 2%) because of the low amount of loose deposits. The distribution of biological stable water had minor effects on the microbiocidal water quality regarding both quantity(ATP 1 ng/L vs. 1.7 ng/L) and community of the bacteria. Whereas the plumbing system has significant contribution to the increase of active biomass(1.7 ng/L vs. 2.9 ng/L) and the changes of bacterial community. The relative abundance of Sphingomonas spp. at tap(22%) was higher than that at water main(2%), while the relative abundance of Pseudomonas spp. in tap water(15%) was lower than that in the water from street water main(29%). Though only one location was prepared and studied, the present study showed that the protocol of making sampling tap on water main offered directly evidences about the impacts of plumbing system on tap water quality, which makes it possible to distinguish and study the processes in distribution system and plumbing system separately.
