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Background: To assess the ability of fluorescence imaging to detect a dose response relationship between fluorosis severity and different levels of fluoride in water supplies compared to remote photographic scoring in selected populations participating in an observational, epidemiological survey in Chiang Mai, Thailand., Methods: Subjects were male and female lifetime residents aged 8-13 years. For each child the fluoride content of cooking water samples (CWS) was assessed to create categorical intervals of water fluoride concentration. Fluorescence images were taken of the maxillary central incisors and analyzed for dental fluorosis using two different software techniques. Output metrics for the fluorescence imaging techniques were compared to TF scores from blinded photographic scores obtained from the survey., Results: Data from 553 subjects were available. Both software analysis techniques demonstrated significant correlations with the photographic scores. The metrics for area effected by fluorosis and the overall fluorescence loss had the strongest association with the photographic TF score (Spearman's rho 0.664 and 0.652 respectively). Both software techniques performed well for comparison of repeat fluorescence images with ICC values of 0.95 and 0.85 respectively., Conclusions: This study supports the potential use of fluorescence imaging for the objective quantification of dental fluorosis. Fluorescence imaging was able to discriminate between populations with different fluoride exposures on a comparable level to remote photographic scoring with acceptable levels of repeatability.

Microcystins are produced by multifaceted organisms called cyanobacteria, which are integral to Africa’s freshwater environments. The excessive proliferation of cyanobacteria caused by rising temperature and eutrophication leads to the production and release of copious amounts of microcystins, requiring critical management and control approaches to prevent the adverse environmental and public health problems associated with these bioactive metabolites. Despite hypotheses reported to explain the phylogeography and mechanisms responsible for cyanobacterial blooms in aquatic water bodies, many aspects are scarcely understood in Africa due to the paucity of investigations and lack of uniformity of experimental methods. Due to a lack of information and large-scale studies, cyanobacteria occurrence and genetic diversity are seldom reported in African aquatic ecosystems. This review covers the diversity and geographical distribution of potential microcystin-producing and non-microcystin-producing cyanobacterial taxa in Africa. Molecular analyses using housekeeping genes (e.g., 16S rRNA, ITS, rpoC1, etc.) revealed significant sequence divergence across several cyanobacterial strains from East, North, West, and South Africa, but the lack of uniformity in molecular markers employed made continent-wise phylogenetic comparisons impossible. Planktothrix agardhii, Microcystis aeruginosa, and Cylindrospermopsis raciborskii (presently known as Raphidiopsis raciborskii) were the most commonly reported genera. Potential microcystin (MCs)-producing cyanobacteria were detected using mcy genes, and several microcystin congeners were recorded. Studying cyanobacteria species from the African continent is urgent to effectively safeguard public and environmental health because more than 80% of the continent has no data on these important microorganisms and their bioactive secondary metabolites.

This paper describes a method for deriving site-specific water quality criteria for selenium using a two-step process: (1) gather information on selenium residues and biological effects at the site and in down-gradient systems and (2) examine criteria based on the degree of bioaccumulation, the relationship between measured residues and threshold concentrations for reproductive effects in fish and wildlife, and any observed reproductive impacts. Several outcomes are possible--criteria can be left unmodified, adjusted upward by a fixed amount (50%), or adjusted downward by one of three amounts (25, 50, or 75%). A criterion (existing or proposed) is lowered or raised by an amount that is proportional to the magnitude of bioaccumulation and toxic effects present--i.e., the degree of biological hazard. Criteria can be modified under two circumstances: (1) diagnostic residues and toxic effects must be coupled (present) in order to lower a criterion or (2) diagnostic residues and toxic effects must be coupled (absent) in order to raise a criterion. Coupling residues and effects makes the procedure sensitive to the natural inter- and intraspecific variation in bioaccumulation and toxic responses exhibited by fish and wildlife in aquatic ecosystems. The goal is to establish criteria that keep food-chain bioaccumulation below levels that result in toxicity to fish and wildlife. Precautions are given for those attempting to apply the generic EPA model for implementing national water quality criteria to a site-specific selenium criterion.

Compared with wood pulp, straw pulp and papermaking, because of lower cost and abundancy of raw material, has become an indispensable approach in paper industry of China. However, its further application is limited by huge water consumption and wastewater discharge. By employing substance flow analysis, this study built up an optimization model and a performance evaluation system of water saving for the water-use network of a straw pulp and paper enterprise, after identifying the problems in present water consumption. Accordingly, an optimization plan was proposed to combine man-made water circulation with natural water circulation system. Additionally, a contrast analysis between the present and optimized water use was conducted. At last, we applied the proposed optimization plan to one of the most important and largest enterprises of straw pulp and paper industry in China as an illustration. Theoretically, water consumption could be reduced by 75.4 % without wastewater discharge after optimization. [ABSTRACT FROM AUTHOR]

The pulp and paper industry consumes enormous quality of freshwater, leading to wastewater. It must be treated to remove pollutants, particularly residual dyestuffs, before releasing them to water bodies to avoid adverse environmental effects. The traditional wastewater treatment methods used for the pulp and paper industry are less efficient in colour and chemical oxygen demand (COD) removal. The current study is aimed at developing a novel catalyst for the catalytic ozonation of pulp and paper wastewater with better colour and COD removal for sustainable resources of clean water. The proposed catalyst is impregnated by iron on natural zeolites. Various parameters such as catalyst dose, pH, ozone dose, initial COD concentration, and reaction time are studied and optimized. The performance was evaluated by comparing the results with the single ozonation process (SOP) and catalytic ozonation process (COP). The highest COD and colour reduction efficiencies have been achieved, i.e., 71%, and 88% at a natural pH of 6.8. The proposed process achieved higher COD and colour efficiencies than the single ozonation process and catalytic ozonation process using raw zeolites. The improvement in efficiencies are 23% and 29% for SOP and 17% and 19% for COP, respectively. Hence, the results proposed the sustainability and applicability of COP to treat paper and pulp sector effluent. [Display omitted] • A novel Fe-zeolite catalyst was developed for catalytic ozonation process. • Performance of single ozonation process and catalytic ozonation process was evaluated. • Under optimized condition the catalyst remains efficient even after 5 cycles. • 71% of COD were eliminated using Fe/NZ as catalyst in catalytic ozonation process. • The optimum ozone dose for COD and color removal was 0.3 mg/ml of wastewater. [ABSTRACT FROM AUTHOR]

As climate change strains the world's freshwater resources, access to safe and clean water becomes limited. The use of alternative water sources, such as rooftop-harvested rainwater, has become one mechanism to address freshwater scarcity in the American Southwest, particularly when it comes to home gardening. The University of Arizona's Project Harvest, in partnership with the Sonora Environmental Research Institute, Inc., is a multi-year, co-created citizen science project aimed at increasing current understanding of harvested rainwater quality. Citizens in four Arizona, USA, communities (Hayden/Winkelman, Globe/Miami, Dewey-Humboldt, and Tucson) submitted harvested rainwater samples over 3 years. The harvested rainwater samples were then analyzed using IDEXX Colilert® for total coliforms and E. coli and using Hach PathoScreen™ test for sulfate-reducing bacteria (SRB). This study design allows for the validation of a low-cost, at-home alternative methodology for testing rainwater for bacteria that may indicate fecal contamination. In total, 226 samples were tested using both methodologies, revealing a positive correlation (r=0.245; p<0.002) between total coliform MPN and SRB MPN, but no discernable correlation between E. coli MPN and SRB MPN. This work indicates a potential value of SRB testing for harvested rainwater if cost, laboratory access, and fecal contamination are of concern., (© 2023. The Author(s).)

Based on the Essential Science Indicators (ESI) database, this study analyzed 798 top papers in the subject category of Water Resources from 2008 to 2018. The 798 top papers include 797 highly cited papers and 21 hot papers in the field. Distributions of document type, language of publication, scientific output, and publication of journals are reported in this article. Co-authorship network visualization of author, organizations and countries, co-occurrence network visualization of all keywords was visualized using VOS viewer software. Results showed that 798 papers, all written in English, were from 2,845 authors, 80 countries/territories and 1,107 organizations, listed in 49 journals in the field of water resources. Top 5 core journals with higher impact factor ranked as Water Research, Journal of Hydrology, Desalination, Catena and Advances in Water Resources. Top 5 countries and regions were USA, China, Australia, England and Germany. Top 5 organizations were Chinese Academy of Sciences, University of California System, Helmholtz Association, Delft University of Technology and Eth Zurich. Based on the analysis of network map of VOSviewer, there is cooperation for authors, organizations and countries or regions. The analysis of keywords showed that the research of water resource was separated 6 clusters. This study demonstrates that there are more top papers come from journals with the higher IF and higher rank in Category of Water Resources. Therefore, authors can choose their ideal Journal with a high impact factor to publish papers in the English language related to this research field. [ABSTRACT FROM AUTHOR]

An accidental or intentional contamination event can raise health and sociopolitical concerns, erode public trust, and affect the operation of water distribution systems. In this regard, emergency management plans are required to describe the necessary measures in order to deal with a threat. This study was carried out to investigate the best ways to manage intrusion in a water distribution network. In this research, the optimal management approach to deal with chemical contamination in a water distribution network was examined under three scenarios using the particle swarm optimization method. In each scenario, three management solutions were used to manage the contamination, including closing the pipe, opening the fire hydrant, and using a combination of pipe closure and fire hydrant opening. Contamination risk impact on consumers' health was assessed in the network's emergency status and after implementation of the best pollution management scenarios. The results showed that in the benchmark network, pipe closure was slightly more successful than opening of the fire hydrant valve. In pollution management of a real network, pipe closure was less effective than the hydrant opening in all scenarios. Generally, all applied scenarios were successful in reducing the contamination risk among the exposed people, so that carcinogenic and non-carcinogenic risks reduced by 100% in all scenarios compared to the non-management state., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Identifying suitable zones for surface water storage and groundwater recharge is needed to enhance irrigation water availability. This study was undertaken to map rainwater harvesting (RWH) potential zones using geospatial tools and analytic hierarchy process (AHP). The suitable locations for RWH were also mapped using the Boolean logic concept. The surface runoff is a vital factor to demarcate the appropriate zones for RWH. The curve number approach was used to estimate the surface runoff potential. The runoff coefficient (RC) map was generated based on rainfall and surface runoff depth. Weights have been allocated to selected themes of RC, drainage density, and slope. The themes were integrated using geographic information system (GIS) and AHP to demarcate the suitable zones for RWH. The derived RWH potential map was categorized into zones like "very good," "good," "moderate," "poor," and "very poor" with an aerial extent of 14.3%, 24.7%, 28.3%, 20.2%, and 12.6%, respectively. The area suitable for farm ponds was found to be about 9% (408 km 2 ), 13% (329 km 2 ), and 4% (244 km 2 ) in Mirzapur, Chandauli, and Sonbhadra districts, respectively. Furthermore, 22, 15, and 21 locations were found suitable for check dams in Mirzapur, Chandauli, and Sonbhadra districts, respectively. At a large scale, effective planning of water management strategies based on multicriteria decision analysis and GIS offers increased availability of surface and groundwater resources and may help for enhancing the agricultural land use options. The higher resolution maps may be further utilized to plan RWH strategies at village level., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Despite regularly being criticized, the Impact Factor (IF) remains a widely used journal analysis metric. In the Water Resources category of the Web of Science, a thorough investigation of the reliability of this metric is lacking. This study analyzed the citation records of the top 10 journals from 2002 through 2021 for the last two decades. Important to note, there are inconsistencies in the Web of Science database. Contradictory to many fields, few papers are uncited. However, the Simpson paradox applies. More specifically, on the one hand, the correlation between citations to papers 7 years post publication and 1 or 2 years post publication (which determine the IF) has increased, which supports this metric. On the other hand, many of the most highly cited papers at the time of the IF calculation are lowly cited 5 years afterward. Additionally, most currently very highly cited papers were relatively uncited when they were used in the IF calculation. This raises doubt about the usefulness of this metric. For a limited number of journals, papers from individual nations strongly influence the IF. Also, for a few journals, the IFs are strongly influenced by review papers, but leaving these out of the IF does change the top 3 and 10 of the rankings. The general conclusion is that IFs do contain some valuable information about the journals' citation impact, but that using them to rank journals is questionable practice. Plain Language Summary: Impact Factors (IFs) continue to be very frequently used to evaluate researchers' publication records. They are calculated in a very simplistic manner, and are essentially an attempt to summarize a very complicated issue (publication quality) into one single metric. This paper shows that care must be taken when applying this practice. Not only does the data set contain errors, there are a number of other reasons why these IFs are not reliable indicators of a journal's quality. Key Points: In many cases the calculation of the Impact Factor (IF) by the Web of Science is contradictory with their own dataAnother number of issues have been identified which raise doubt on the IF as a measure of journal qualityA number of recommendations for a better use of the literature databases have been made [ABSTRACT FROM AUTHOR]

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Thermal aging of insulation paper occurs during transformer operation, with the water produced during aging accelerating the thermal aging process. Insulation paper aging largely determines the operational life of a transformer pressboard; accordingly, research pertaining to insulation paper enhancement is significant with respect to the functional safety of transformers. Within molecular research, particularly that focusing on molecular simulation, appropriate force field selection is paramount in order to acquire accurate results, in addition to appropriately reflecting cellulose thermal stability and associated degradation mechanisms. In the current study, two diverse cellulose models (water only; water, dicyandiamide, melamine and polyacrylamide) are developed and analyzed. Numerous model variables, including the diffusion coefficient of water and cellulose chain distance, are collated, in order to examine the effects of amines on the thermal stability of cellulose. Additionally, a novel insulation paper is formulated by combining traditional insulation paper with three diverse amines; an accelerated aging experiment is thus undertaken, comparing traditional and modified insulation paper samples at 110 °C, together with periodic assessment of both microwater content and the degree of polymerization (DP). Results indicate that during transformer operation, a higher degree of elasticity is associated with the modified insulation paper, thus significantly increasing its toughness and extensibility, in parallel with decreasing it brittleness. Results also show that the DP associated with cellulose comprising the modified insulation paper decreases at a reduced rate, with measured water content significantly less than that of traditional insulation paper. Simulation results are consistent with experimental findings. Therefore, it may be concluded that the thermal aging properties of cellulose significantly improve upon addition of dicyandiamide, melamine, and polyacrylamide as thermal stabilizers. [ABSTRACT FROM AUTHOR]

The common perception of people about recycling involves reusage of aluminum cans, glass bottles, and newspapers, whereas recycling of water resources is a most important aspect nowadays. Water recycling is known to reuse cleaned wastewater for beneficial applications including agricultural and landscape irrigation, industrial activities, and replenishing a groundwater using the latest technologies. The current methods have some flaws in the evaluations of water resources' recycling systems such as large mean square error, time complexity, and low-evaluation efficiency; therefore, this paper proposes an online evaluation method for the recycling process of water resources in urban landscaping. The health model of water resources recycling in urban landscaping has been analyzed using fuzzy-based approach. Second, the evaluation index system of water resources' recycling is also analyzed using the ecological water-level analysis results, water resource quality, water resource abundance, and water resource utilization rate. Then, the extension of analytic hierarchy process (AHP) is utilized to calculate the weight of water recycling evaluation index. Then a fuzzy-based comprehensive evaluation method is used to find the online evaluation model of the water recycling. Eventually, the evaluation of the effect of water recycling in urban landscaping is performed and analysis is made for decision-making. The results prove that the proposed AHP and fuzzy method has a low mean square error and high accuracy. [ABSTRACT FROM AUTHOR]

The recycled paper industry produces tons of waste whose disposal is a cost for industry and the environment. This research examines the suitability of de-inked paper sludge (DPS), after pelletization, as a sustainable alternative component to a peat-based growing media, creating ideal root conditions for tree development (e.g. high water storage, low compaction). DPS, tested on Lepidium sativum L. germination, did not show toxicity effects. Three species, Quercus ilex L., Lagerstroemia indica L. and Prunus serrulata "Kanzan", were planted in 40 cm Ø pots filled with a control (peat, pumice and zeolite) and the experimental substrate (compost, DPS pellets, pumice and zeolite). After two years in the nursery, the trees were planted in situ. The physical and chemical properties of substrates were analyzed. Plant morphological and physiological parameters were monitored: trunk diameter, leaf dry matter, leaf nitrogen, chlorophyll, and photosynthetic efficiency. The new substrate showed higher C org (+135%), total N (+73%) and easily available water (+19%), compared to the control substrate used in the nursery. In this new substrate, the trees showed similar radial growth values to the control in the nursery and after transplanting in situ improved their photosynthetic performance in terms of quantum yield of photosystem II (+36%, and +29% in P. serrulata and L. indica , respectively) and electron transport rate (+39%, +25%, and +32% in P. serrulata , Q. ilex and L. indica , respectively). Pelletization represents an attractive amendment for growing media, which enhances the plant's physiological health status. This study proposes alternative recovery methods for paper industry waste with low environmental impact. As the process is developed locally, it should also contribute to reducing energy-related CO 2 emissions from transport. Pelletization represents an attractive novelty in the use of DPS as amendment for growing media, which enhances the plant's physiological health status. This study proposes alternative recovery methods for paper industry waste with low environmental impact. As the process is developed locally, it should also contribute to reducing energy-related CO 2 emissions from transport. Image 1 • De-inked paper sludge and mature compost mixed were tested as a new substrate. • The new substrate showed high organic carbon, nitrogen and water availability. • Holm oak, Crape myrtle and Kanzan cherry grew healtlhy in the new substrate. • The new substrate is suitable for tree growth to overcome transplanting stress. • The study proposes alternative recovery methods for paper industry waste. [ABSTRACT FROM AUTHOR]

Microcystins are produced by multifaceted organisms called cyanobacteria, which are integral to Africa's freshwater environments. The excessive proliferation of cyanobacteria caused by rising temperature and eutrophication leads to the production and release of copious amounts of microcystins, requiring critical management and control approaches to prevent the adverse environmental and public health problems associated with these bioactive metabolites. Despite hypotheses reported to explain the phylogeography and mechanisms responsible for cyanobacterial blooms in aquatic water bodies, many aspects are scarcely understood in Africa due to the paucity of investigations and lack of uniformity of experimental methods. Due to a lack of information and large-scale studies, cyanobacteria occurrence and genetic diversity are seldom reported in African aquatic ecosystems. This review covers the diversity and geographical distribution of potential microcystin-producing and non-microcystin-producing cyanobacterial taxa in Africa. Molecular analyses using housekeeping genes (e.g., 16S rRNA, ITS, rpoC1, etc.) revealed significant sequence divergence across several cyanobacterial strains from East, North, West, and South Africa, but the lack of uniformity in molecular markers employed made continent-wise phylogenetic comparisons impossible. Planktothrix agardhii, Microcystis aeruginosa, and Cylindrospermopsis raciborskii (presently known as Raphidiopsis raciborskii) were the most commonly reported genera. Potential microcystin (MCs)-producing cyanobacteria were detected using mcy genes, and several microcystin congeners were recorded. Studying cyanobacteria species from the African continent is urgent to effectively safeguard public and environmental health because more than 80% of the continent has no data on these important microorganisms and their bioactive secondary metabolites. [ABSTRACT FROM AUTHOR]

Abstract: Growing concerns about water availability is becoming of major interest for governments around the world. Various water initiatives are under study to establish recommendations on water governance and policies to ensure the sustainability of water supply for people and industries. As the pulp and paper industry is one of the major users of water, the implementation of such water initiatives will force the industry to improve their water management programs by moving further towards closed-cycle papermaking. Fresh water consumption reduction induces a gradual accumulation of dissolved and colloidal substances (DCSs) in process waters with detrimental effects on papermaking operations and paper quality. DCS removal is the key factor to meet targeted fresh water consumption levels. Contaminant adsorption on a modified solid sorbent in a fluidized bed reactor has been proposed for paper machine white water treatment. Cationic solid sorbents were synthesized by two different methods: (1) Silica nanoparticles were deposited on silicon wafers and silanized by quaternary ammonium organosilanes (TMAC, TDDMAC, and ODDMAC) and (2) Silicon wafers grafted with cationic polymer (MeDMA) were synthesized via atom transfer radical polymerization (ATRP). The growth of silica nanoparticles on the surface was investigated by scanning electron microscopy (SEM). Both sorbent surfaces were characterized by X-ray photoelectron spectrometry (XPS), contact angles (CA), and conductometric titration to determine quaternary ammonium surface density. Results show that silica particles deposited on silicon wafers increased the specific surface area and the number of active sites for the silanization reaction. The shorter silane alkyl chains increases the silanization rate. The quaternary ammonium quantification by conductometric titration showed that ATRP exhibits higher amine groups/unit surface comparatively to the silanization with TMAC. Both techniques can be used to assess the development of a solid sorbent that will be used in a fluidized bed reactor for paper machine white water treatment. [Copyright &y& Elsevier]

The virtual water flow behind product trade provides researchers with ideas to alleviate water problems in China's coastal areas, with accompanying resource and economic implications. This paper adopts a multi-region input–output model to calculate virtual water flows in coastal areas and analyses resource benefits and economic benefits, by combining the water stress index and shadow price, to measure gains and losses of virtual water flow. This study shows that (1) China's coastal areas depends on external water supplies; (2) virtual water flows between coastal and inland areas generated 38.26 billion m3 of net scarce water savings and CNY 31,751 billion of net economic benefits, indicating that coastal areas benefited from virtual water flows from both resource and economic perspectives; (3) virtual water flows among coastal provinces and cities caused 11.10 billion m3 of net scarce water losses, but generated CNY 9784 billion of net economic gains, indicating that a further intensification of water stress in coastal areas, but such a virtual water flow pattern was beneficial from an economic perspective. This paper reveals the resource and economic impacts of virtual water flow at the national scale and among coastal provinces and cities and further proposes suggestions for promoting the beneficial flow of virtual water in coastal areas. [ABSTRACT FROM AUTHOR]

This paper takes up the qanat of Hassan Abad and its special peculiarities which made it eligible to be nominated as UNESCO World Heritage in 2015. Hasan Abad originates from Ebrahim Abad valley near the town of Mehriz and travels 40 kilometers to Yazd. The water of this qanat is shared out between the town of Mehriz, the village of Dehno and Yazd (district of Hasan Abad). One of the most important properties of this qanat is its territorial cooperation which is resulted from a lax territorial behavior caused by the qanat's dynamics. Dormant territorial behavior can pave the way for a high sense of cooperation and social capital, which are all associated with the peculiarities of the qanat. In the region, the social foundation which has been formed and evolved around the water resources management could have increased the sense of cooperation. Through the research method of grounded theory, this paper tries to answer the question of how a water current like the qanat of Hasan Abad can pave the way for such social convergence and cooperation between three beneficiary territories. [ABSTRACT FROM AUTHOR]

In the paper of [6], maps of suitability predictions for a handful relevant tree species in 30 × 30 m resolution are presented based on ecograms that are linked with interpolated, modeled soil data (subsoil pH, subsoil texture and derived plant available water to 160 cm). We ignore statistical principles if we accept interpolated tree species suitability predictions based on limited sets of soil properties without verifying them with observed, local site and soil data. Commentary to the paper by Roell, Nord-Larsen et al. 'Mapping tree species ecograms based on soil pH and soil water availability across Denmark'. [Extracted from the article]

Crago et al. published two papers in Water Resources Research in 2016 and 2018, respectively, which discussed recent generalized complementary evaporation relationships; they recommended that the lower boundary condition of the Generalized Nonlinear Advection-Aridity (GNAA) model proposed by Brutsaert (2015, https://doi.org/10.1002/2015WR017720) should be modified to y = 0 at x = xmin, where xmin-[0,1]. First, it is shown herein that the rescaled complementary relationship (CR) y = X, proposed by Crago et al., does not advance the analysis forward, but that instead the rescaling is tantamount to a reversion to an earlier linear and more traditional asymmetric complementary model, in which the parameter b is a function of xmin. In fact, at xmin = 0, y = X the rescaled formulation becomes physically unrealistic. The second part of this comment deals with the extended quartic form of GNAA model. The nature of the adjustable parameter c in this extended formulation is further explored, and it is shown that while its lower limit is -1, calibration with actual data can result in values in excess of 2. Such calibration allows then the estimation of xmin as a function of c, that is, xmin = f (c). This way, in addition to satisfying the original four boundary conditions, the extended GNAA model also satisfies the boundary condition of y = 0 at x = xmin. The physical variables affecting the nature of the parameter c and its relationship with Epo/Epmax will require further investigation. [ABSTRACT FROM AUTHOR]