bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular surveillance of Cryptosporidium and Giardia duodenalis in sludge and spent filter backwash water of a water treatment plant
Authors: Ladeia Winni Alves , Martins Felippe Danyel Cardoso , e Silva Camila Fernanda Rosolen , Freire Roberta Lemos 
Published: October 2018

Abstract
The purpose of this study was to monitor the presence of Cryptosporidium spp. and Giardia duodenalis in a water treatment plant (WTP) using settling sludge and backwash water (BW) samples in previous and post the deflocculation of polyaluminium chloride (PAC) flacks. Eleven collections were performed. BW and settling sludge (SSF) were concentrated by calcium carbonate flocculation, and another aliquot of settling sludge (SSC) by centrifugation. The samples were divided as follows: Group A, containing 33 samples without degradation of PAC flakes, and Group B, with degradation by alkalinization with 10 M NaOH. Sample DNA was extracted with a commercial kit, and nested polymerase chain reaction (PCR) was used to detect Cryptosporidium and G. duodenalis. All samples from Group A were negative for Cryptosporidium spp., and 6.1% (2/33) were positive for G. duodenalis in SSC samples. While the absence of Cryptosporidium may be due to a low contamination level of the water resource, the presence of G. duodenalis indicates contamination of the raw water. The detection of G. duodenalis in SSC samples indicates that this detection method was the most effective. The 33 samples from Group B were negative for both protozoa, probably due to the presence of aluminium and humic substances.
River water analysis using a multiparametric approach: Portuguese river as a case study
Authors: Barbosa-Vasconcelos Ana , Mendes Ângelo , Martins Flávia , Lopes Elisabete , Machado Ana , Bordalo Adriano A. , Vaz-Pires Paulo , Vieira Natividade , Martins da Costa Paulo , Bessa Lucinda J. 
Published: October 2018

Abstract
The Ave River in northern Portugal has a history of riverbanks and water quality degradation. The river water quality was assessed by physicochemical, biological (macroinvertebrates) and microbiological (Enterococcus spp. and Escherichia coli) parameters in six locations (A–F, point A being the nearest to the source) throughout its course during a year. Epilithic biofilms were studied through polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE). Antimicrobial susceptibility testing helped with selecting isolates (n = 149 E. coli and n = 86 enterococci) for further genetic characterization. Pursuant to physicochemical and macroinvertebrates-based parameters, the river water was of reasonable quality according to European legislation (Directive 2000/60/EC). However, the microbiological analysis showed increased fecal contamination downstream from point C. At point D, four carbapenem-resistant E. coli isolates were recovered. Paradoxically, point D was classified as a point of ‘Good Water Quality’ according to macroinvertebrates results. Point F presented the highest contamination level and incidence of multidrug-resistant (MDR) isolates in the water column (13 MDR enterococci out of 39 and 33 MDR E. coli out of 97). Epilithic biofilms showed higher diversity in pristine points (A and B). Thus, biological and microbiological parameters used to assess the water quality led to divergent results; an outcome that reinforces the need for a holistic evaluation.
Removal of Escherichia coli from well water using continuous laminar flow in a channel system containing PPy/Cu modified electrodes
Authors: González M. B. , Brugnoni L. I. , Flamini D. O. , Quinzani L. M. , Saidman S. B. 
Published: October 2018

Abstract
Polypyrrole (PPy) films modified with copper species were used for disinfection of well water contaminated with Escherichia coli (E. coli). For that purpose a laboratory-scale continuous flow system with a parallel plate flow chamber configuration was implemented operating under laminar flow. Three flow rates were considered. The testing conditions did not affect the morphology of the modified PPy films, even after 5 h of continuous use at the largest flow rate examined. The results show that the bacteria killing process can be described by a first-order kinetic law at all Reynolds numbers. As the flow rate increases, the concentration of Cu species released from the electrodes enhances, accelerating the disinfection process. Re-inoculation and Cu-recharging tests showed bactericidal effects very similar to those displayed by the freshly prepared electrodes. It is concluded that PPy/Cu-modified electrodes installed in the laboratory-scale continuous flow system are effective for the water disinfection process.
Evaluation of denaturing gradient gel electrophoresis for the detection of mycobacterial species and their potential association with waterborne pathogens
Authors: Aboagye G. , Rowe M. T. 
Published: October 2018

Abstract
The versatility of denaturing gradient gel electrophoresis (DGGE) protocol provides enough grounds for its wide application over an array of microorganisms. This work was designed to evaluate DGGE for the detection and confirmation of mycobacteria and their association, if any, with waterborne pathogens. A total of 76 samples comprising raw untreated water, schmutzdecke, floccules and final treated water obtained from a common water source, and two water treatment works (WTW1 and WTW2), were analysed. Thirty-five species were identified from the overall samples, with 7% (5/76), 13% (10/76) and 26% (20/76) from the common raw water source, WTW1 and WTW2 respectively. The majority of the species were Cyanobacteria, with high dominance in the raw water entering WTW2. In the final treated water of WTW1 Eutreptiella braarudii was found, and that of WTW2 contained Anabaena nereformis, Anabaena torulosa and Podocarpus nerrifolius. Furthermore, one Mycobacterium species was found in the raw water of WTW1 aside from the detection of Mycobacterium avium ssp. paratuberculosis by the technique. No association between mycobacteria and the other species was observed. This implies DGGE may be employed to study the diversity of other akin mycobacterial species from various sources, and not as a direct means of elucidating microbial associations.
Valuing excess fluoride removal for safe drinking water in Kenya
Authors: Ndambiri Hilary , Rotich Emmy 
Published: October 2018

Abstract
The study uses contingent valuation framework to assess the welfare benefits of removing excess fluoride from drinking water among households in Baringo County, Kenya. A conventional payment card is used to draw preferences from households in order to estimate the mean and median willingness to pay for excess fluoride removal from drinking water in the county. Through interval regression analysis, the study found that households were, on average, willing to pay Kshs. 202.25 ($2.02) and a median of Kshs. 162.50 ($1.63) to remove excess fluoride from drinking water. The mean and median welfare values of removing excess fluoride from water were estimated at Kshs. 112.4 ($1.12) and Kshs. 90.3 ($0.90) million, respectively. These amounts were significantly found to increase with male gender, education, household income, living in own house, type of water source, perceived water quality, distance to nearest water source, payment vehicle used and whether household members had suffered from fluorosis. However, these amounts declined with age and household size. On the whole, the study found significant public support towards the removal of excess fluoride in drinking water among the concerned households, which is vital for effective formation and implementation of water quality improvement policies for the county.
Competitiveness of hydropower price and preferential policies for hydropower development in Tibet and the Sichuan-Yunnan Tibetan area of China
Authors: Liu Yue , Huang Weibin , Ma Guangwen , Chen Shijun , Wang Jinlong 
Published: October 2018

Abstract
Tibet and the Sichuan-Yunnan Tibetan area have enormous potential for hydropower development. Therefore, accelerating hydropower development in these areas can contribute to water resource utilisation and help relieve the poverty, which has also become a necessary choice of national strategic importance to comply with energy-saving, emission reduction, and ‘power transmission from west to east’ policies. Under existing policies, research has shown that the basic costs of electricity from the typical plants in Tibet and the Sichuan-Yunnan Tibetan area are high and uncompetitive, so that investment enthusiasm for hydropower companies will wane and water resource utilisation will be affected. In this study, we suggest policies to improve the competitiveness and sustainability of the hydropower development in the Tibet and Sichuan-Yunnan Tibetan areas; eventually, the water resources therein can be more effectively utilised. Research has indicated that drafted preferential policies can effectively decrease the cost price. Additionally, the hydropower industry in these areas should be incorporated into the national primary energy balance, forming a government-dominated market mechanism. This would consist of a mandatory market share of the hydropower transmitted from Tibet and the Sichuan-Yunnan Tibetan area and hydropower–carbon trade mechanism – the aim being to promote the consumption of hydropower across the nation.
Analysis of halogenated flame retardants in Canadian wastewater treatment plants using gas chromatography–tandem mass spectrometry (GC-MS/MS)
Authors: Shanmuganathan Meera , Zhang Zifeng , Sverko Ed , Brymer Rachel , Gill Biban , Smyth ShirleyAnne , Marvin Christopher H. 
Published: October 2018

Abstract
An investigation of brominated flame retardants (BFRs), polybrominated diphenylethers (PBDEs), and chlorinated flame retardants was conducted in samples from Canadian wastewater treatment plants (WWTPs). The penta-BDE mixture and deca-BDE were most commonly detected. Median removal efficiencies of PBDEs by WWTPs were 71% to 99% and higher concentrations of PBDEs were found in influent samples in summer, compared to winter. Three novel brominated flame retardants (nBFRs) including 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTeBB or TBB), and bis(2-ethyl-1-hexyl)tetrabromophthalate (BEHTBP or TBPH) were detected in greater than 80% of influents and biosolids. Median removal efficiencies were 45% to 99% for BTBPE, 63% to 99% for TBB, and 88% to 99% for TBPH. Detection of total dechlorane plus ((DP) syn and anti) was greater than 90% in both wastewater and biosolids samples. However, median removal efficiencies were between 51% and 66% for total DP. Overall, PBDEs were effectively removed via different treatment processes, while BTBPE, TBB, and DP exhibited lower removal rates, which could be due to their physical chemical properties.
Electrochemical treatment for greywater reuse: effects of cell configuration on COD reduction and disinfection byproduct formation and removal
Authors: Drennan Dina M. , Koshy Raji E. , Gent David B. , Schaefer Charles E. 
Published: October 2018

Abstract
Electrochemical (EC) treatment presents a low-energy, water-reuse strategy with potential application to decentralized greywater treatment. This study focused on evaluating the impacts of cell configuration, current density, and cathode material on chemical oxygen demand (COD) removal and disinfection byproduct (DBP) formation in greywater. The formation and/or cathodic removal of active chlorine, perchlorate, haloacetic acids, and trihalomethanes were assessed during EC treatment. DBP formation was proportional to current density in undivided EC cells. Sequential anodic-cathodic treatment in divided EC cells resulted in COD removal in the catholyte and anolyte. The anodic COD removal rate (using a mixed metal-oxide anode) was greater than the cathodic removal rate employing boron-doped diamond (BDD) or graphite cathodes, but anodic and cathodic COD removal was similar when a stainless-steel cathode was used. The overall energy demand required for 50% COD removal was 24% less in the divided cells using the graphite or BDD cathodes (13 W-h L−1) compared to undivided cells (20 W-h L−1). Perchlorate formation was observed in undivided experiments (&gt;50 μg/L), but not detected in divided experiments. While haloacetic acids (HAAs) and trihalomethanes (THMs) were generated anodically; they were removed on the cathode surface in the divided cell. These results suggest that divided configurations provide potential to mitigate DBPs in water reuse applications.
Assessment of the Tarim River basin water resources sustainable utilization based on entropy weight set pair theory
Authors: Lu Shibao , Shang Yizi , Li Wei 
Published: October 2018

Abstract
Scientific assessment provides important tools for the sustainable use of water resources. This paper applies the set pair theory of entropy weight to evaluate the uncertainty involved. A preliminary classification of samples is conducted by calculating the connection degree of each evaluation index, and then uniform, differential and confrontational analyses of set pairs are carried out on the samples to identify their level. In identifying the weight of each evaluation index, the entropy value theory of information theory is introduced into the model. Combined with Tarim 2004 to 2007 water resource data, an evaluation of the sustainable water resource utilization in this region is made from the social and economic, water resource and ecological environmental water resource evaluation index system. The results show that the development and utilization of water resources in the Sanyuanliu region of Tarim are saturated, and the utilization of water resources in the Hotan region (III), Aksu region (III) and Kashgar region (III) appears to be unsustainable. After a comparison with other methods, it is concluded that the evaluation result provided by the method is reasonable and objective.
Thermal stratification and its relationship with water quality in the typical tributary bay of the Three Gorges Reservoir
Authors: Jin Juxiang , Wells Scott A. , Liu Defu , Yang Guolu 
Published: October 2018

AbstractThe effect of thermal stratification and its relationship with water quality was researched by field observation in this study. Through assessing the degree of thermal stratification by calculating the dimensionless parameter of thermal resistance to mixing (RTRM) indices from 2008 to 2010, it indicated that the water body of Xiangxi River was stratified strongly in the summer months. The analysis of the degree of thermal stratification with both the meteorological and hydrodynamic factors showed thermal stratification intensity was more sensitive to meteorological factors in Xiangxi River. Through the analysis of the relationship between thermal stratification and water quality, the results indicated that the concentration of Chlorophyll a was higher in the epilimnion affected by the thermal stratification, which could cause algal bloom. The results may further help to evaluate the thermal stratification role in eutrophication process and algal bloom formation in Xiangxi River.
Experimental investigation of a poly-energy multi-effect still in Algeria
Authors: Abdessemed Amina , Boubekeur Ilies , Boublai Noureddine , Bougriou Cherif 
Published: October 2018

Abstract
The present paper presents a realization of a poly-energy four-stage still, which can operate with three different sources of: electrical resistance (photovoltaic panel), photo-thermal solar collector and vegetable or animal waste. In this work, the effect of the position and the number of trays on the water productivity of a multi-effect still has been experimentally investigated for the first time. A plate was used, then placed in different heights, and then two and three and finally four trays were used. It is concluded that the effect of the tray position has a great influence on the production of distilled water in contrast to the number of trays, and when increasing the number of trays, the production of the distilled water is increased. The maximum production obtained from distilled water is 1 l/h.m². The use of a solar panel for the production of distilled water is unnecessary in oil-producing countries where energy is subsidized. These devices or their components are generally imported and their cost is very expensive. The damping time of these devices is very long.
Vulnerability assessment and potential contamination of unconfined aquifers
Authors: Caprario J. , Rech A. S. , Finotti A. R. 
Published: October 2018

Abstract
The decline in groundwater availability and quality has become a worldwide issue and has been the subject of several studies in recent decades. In this sense, the goal of this study is to assess the vulnerability of the Campeche Aquifer (Florianopolis, Brazil), identifying potential areas of possible contamination by the direct infiltration of runoff in drainage compensatory techniques. To achieve this goal, the following methodological steps were used: (1) data collection and preparation, (2) application of the DRASTIC model, (3) sensitivity analysis and (4) analysis of potential contamination by compensatory techniques. The results show that approximately 33% of the aquifer area presented moderate vulnerability to contamination. However, 29% of the remaining areas had high and extremely high vulnerability. Analysing the potential of contamination with drainage compensatory structures we verified that approximately 95% of them are located in areas of vulnerability classified as moderate and high. The other 5% were identified in areas with extremely high vulnerability. Sensitivity analyses indicated that the removal of topography, soil type and the impact of the vadose zone caused a large variation in vulnerability index. It is evident that there is a high potential of contamination of groundwater by direct infiltration of drainage compensatory structures.
Urban stormwater runoff treatment of Nainital Lake's catchment: an application of ballasted sand flocculation technology
Authors: Kumar Sumant , Kazmi Absar Ahmad , Ghosh Narayan Chandra , Kumar Vinod , Rajpal Ankur 
Published: October 2018

Abstract
Stormwater runoffs are one of the primary causes for deteriorating water quality in the Nainital Lake, India – a prominent tourist attraction and the sole drinking water source for the habitants of Nainital City. Treatment of fluctuating runoffs and contaminant influxes before mixing with the lake's water by conventional methods would require a large land footprint, which is a big constraint in the Nainital because of the hilly region. Ballasted sand flocculation (BSF) technology requires much less land footprint; a full-scale 1 MLD capacity pilot plant was applied for treatment of stormwater runoffs of the Nainital Lake. Twenty-eight storm events were monitored for runoff characterization and for evaluating the performance of BSF technology. The runoff water showed marked variation especially for total suspended solids (TSS), total phosphorus (TP), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total coliform (TC) and fecal coliform (FC) with maximum concentrations of 964 mg/l, 2.35 mg/l, 520 mg/l, 299 mg/l, 21 × 105 MPN/100 ml and 14 × 104 MPN/100 ml. The performance analyses results of the pilot plant revealed that the contaminants including trace metals in the stormwater runoff were reduced appreciably and the pollutant removal efficiencies were found to be largely unaffected by fluctuation of the influent contaminants' concentration.
Impacts of graywater irrigation and soil conditioning with mulch on cotton growth and soil properties
Authors: Sheng Z. , Abudu S. , Ganjegunte G. 
Published: October 2018

Abstract
Field experiments were conducted to evaluate the impacts of graywater irrigation with and without soil conditioning with mulching on cotton growth and soil properties in El Paso, Texas, USA. Treatments included in the study were: freshwater irrigation without soil conditioning (control, treatment T0), freshwater irrigation with soil conditioning (treatment T1), graywater irrigation without soil conditioning (treatment T2) and with soil conditioning (treatment T3) with four replications. The pH, sodium absorption ratio (SAR) and electrical conductivity (EC) values of the graywater used in the study were 8.19, 16.0 and 1.54 dS/cm respectively. Results showed that graywater irrigation did not have significant impacts on cotton growth and lint yield. Soil conditioning with mulch increased cotton yield significantly (p &lt; 0.05) compared with non-mulching regardless of water types. Graywater irrigation increased soil pH values significantly in the surface depth (0–15 cm), however, it did not have significant effects at greater depths (&gt;15 cm). Significantly higher salinity and sodicity were observed in the upper 30 cm depths in the graywater irrigated mulched soils, while no changes were detected at greater depths (30–45 and 45–60 cm).
Evaluation of the protection against norovirus afforded by E. coli monitoring of shellfish production areas under EU regulations
Authors: Younger A. D. , Teixeira Alves M. , Taylor N. G. H. , Lowther J. , Baker-Austin C. , Campos C. J. A. , Price-Hayward M. , Lees D. 
Published: October 2018

Abstract
EC Regulation 854/2004 requires the classification of bivalve mollusc harvesting areas according to the faecal pollution status of sites. It has been reported that determination of Escherichia coli in bivalve shellfish is a poor predictor of norovirus (NoV) contamination in individual samples. We explore the correlation of shellfish E. coli data with norovirus presence using data from studies across 88 UK sites (1,184 paired samples). We investigate whether current E. coli legislative standards could be refined to reduce NoV infection risk. A significant relationship between E. coli and NoV was found in the winter months (October to February) using data from sites with at least 10 data pairs (51 sites). We found that the ratio of arithmetic means (log10E. coli to log10 NoV) at these sites ranged from 0.6 to 1.4. The lower ratios (towards 0.6) might typically indicate situations where the contribution from UV disinfected sewage discharges was more significant. Conversely, higher ratios (towards 1.4) might indicate a prevalence of animal sources of pollution; however, this relationship did not always hold true and so further work is required to fully elucidate the factors of relevance. Reducing the current class B maximum (allowed in 10% of samples) from 46,000 E. coli per 100 g (corresponding NoV value of 75750 ± 103) to 18,000 E. coli per 100 g (corresponding NoV value of 29365 ± 69) reduces maximum levels of NoV by a factor of 2.6 to 1; reducing the upper class B limit to 100% compliance with 4,600 E. coli per 100 g (corresponding NoV value of 7403 ± 39) reduces maximum levels of NoV by a factor of 10.2 to 1. We found using the UK filtered winter dataset that a maximum of 200 NoV corresponded to a maximum of 128 ± 7 E. coli per 100 g. A maximum of 1,000 NoV corresponded to a maximum of 631 ± 14 E. coli per 100 g.