1,250 research outputs found
Factors Influencing Revenue Collection for Preventative Maintenance of Community Water Systems: A Fuzzy-Set Qualitative Comparative Analysis
This study analyzed combinations of conditions that influence regular payments for water service in resource-limited communities. To do so, the study investigated 16 communities participating in a new preventive maintenance program in the Kamuli District of Uganda under a public–private partnership framework. First, this study identified conditions posited as important for collective payment compliance from a literature review. Then, drawing from data included in a water source report and by conducting semi-structured interviews with households and water user committees (WUC), we identified communities that were compliant with, or suspended from, preventative maintenance service payments. Through qualitative analyses of these data and case knowledge, we identified and characterized conditions that appeared to contribute to these outcomes. Then, we employed fuzzy-set qualitative comparative analysis (fsQCA) to determine the combinations of conditions that led to payment compliance. Overall, the findings from this study reveal distinct pathways of conditions that impact payment compliance and reflect the multifaceted nature of water point sustainability. Practically, the findings identify the processes needed for successful payment compliance, which include a strong WUC with proper support and training, user perceptions that the water quality is high and available in adequate quantities, ongoing support, and a lack of nearby water sources. A comprehensive understanding of the combined factors that lead to payment compliance can improve future preventative maintenance programs, guide the design of water service arrangements, and ultimately increase water service sustainability
Reactions of thiocarbamate, triazine and urea herbicides, RDX and benzenes on EPA Contaminant Candidate List with ozone and with hydroxyl radicals
Second-order rate constants of the direct ozone reactions (kO3,M) and the indirect OH radical reactions (kOH,M) for nine chemicals on the US EPA’s Drinking Water Contaminant Candidate List (CCL) were studied during the ozonation and ozone/hydrogen peroxide advanced oxidation process (O3/H2O2 AOP) using batch reactors. Except for the thiocarbamate herbicides (molinate and EPTC), all other CCL chemicals (linuron, diuron, prometon, RDX, 2,4-dinitrotoluene, 2,6-dinitrotoluene and nitrobenzene) show low reactivity toward ozone. The general magnitude of ozone reactivity of the CCL chemicals can be explained by their structures and the electrophilic nature of ozone reactions. The CCL chemicals (except RDX) are highly reactive toward OH radicals as demonstrated by their high kOH,M values. Ozonation at low pH, which involves mainly the direct ozone reaction, is only efficient for the removal of the thiocarbamates. Ozonation at high pH and O3/H2O2 AOP will be highly efficient for the treatment of all chemicals in this study except RDX, which shows the lowest OH radical reactivity. Removal of a contaminant does not mean complete mineralization and reaction byproducts may be a problem if they are recalcitrant and are likely to cause health concerns
Reactions of thiocarbamate, triazine and urea herbicides, RDX and benzenes on EPA Contaminant Candidate List with ozone and with hydroxyl radicals
Second-order rate constants of the direct ozone reactions (kO3,M) and the indirect OH radical reactions (kOH,M) for nine chemicals on the US EPA’s Drinking Water Contaminant Candidate List (CCL) were studied during the ozonation and ozone/hydrogen peroxide advanced oxidation process (O3/H2O2 AOP) using batch reactors. Except for the thiocarbamate herbicides (molinate and EPTC), all other CCL chemicals (linuron, diuron, prometon, RDX, 2,4-dinitrotoluene, 2,6-dinitrotoluene and nitrobenzene) show low reactivity toward ozone. The general magnitude of ozone reactivity of the CCL chemicals can be explained by their structures and the electrophilic nature of ozone reactions. The CCL chemicals (except RDX) are highly reactive toward OH radicals as demonstrated by their high kOH,M values. Ozonation at low pH, which involves mainly the direct ozone reaction, is only efficient for the removal of the thiocarbamates. Ozonation at high pH and O3/H2O2 AOP will be highly efficient for the treatment of all chemicals in this study except RDX, which shows the lowest OH radical reactivity. Removal of a contaminant does not mean complete mineralization and reaction byproducts may be a problem if they are recalcitrant and are likely to cause health concerns
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Adapting Collaborative Approaches for Service Provision to Low-Income Countries: Expert Panel Results
The international development sector is increasingly implementing collaborative approaches that facilitate a range of sectoral-level stakeholders to jointly address complex problems facing sustainable public service delivery, for which guidance does not explicitly exist. The literature on collaborative approaches has been built on experiences in high-income countries with vastly different governance capabilities, limiting their global relevance. A Delphi expert panel addressed this need by evaluating 58 factors hypothesized in the literature to contribute to the success of collaborative approaches. The panel rated factors according to their importance in low-income country contexts, on a scale from Not Important to Essential. Experts agreed on the importance of 49 factors, eight of which were essential for success. Rich qualitative data from open-ended responses revealed factors that may be unique to low-income country contexts and to service delivery applications, including how government capacity, politics, donor influence, and culture can influence decisions on structuring leadership and facilitation roles, appropriately engaging the government, and building legitimacy. Key considerations for future practice and research are summarized in a table in the appendix. This study contributes to both literature and practice by identifying the relative importance of factors to consider when designing collaborative approaches in low-income countries with limited governance capabilities.</div
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Understanding Rural Water Services as a Complex System: An Assessment of Key Factors as Potential Leverage Points for Improved Service Sustainability
Rural water supply services worldwide consistently fail to deliver full public health impacts as intended due to a low service sustainability. This failure is increasingly attributed to weak local systems composed of social, financial and environmental factors. Current approaches in the water, sanitation and hygiene (WASH) sector for understanding and improving these systems typically focus on the strength and capacity of these factors, but not the interactions between them. We contend that these approaches overlook the inherent complexity and context-specific nature of each local system. To assess this complexity, we conducted four participatory factor mapping workshops with local stakeholders across multiple rural water contexts to identify the factors and interactions that support service sustainability. We then evaluate the potential for factors to act as strategic leverage points based on influence, dependence and feedback metrics that arise from their interactions with other factors. We find that while participants across the contexts tend to identify a common set of factors, the interactions amongst those factors and their individual ability to influence service sustainability varies considerably across contexts. These findings suggest that a more intentional focus on factor interactions in WASH systems could lead to more effective strategies for improving service sustainability.</div
Adenosine receptors in GtoPdb v.2021.2
Adenosine receptors (nomenclature as agreed by the NC-IUPHAR Subcommittee on Adenosine Receptors [110]) are activated by the endogenous ligand adenosine (potentially inosine also at A3 receptors). Crystal structures for the antagonist-bound [153, 313, 221, 61], agonist-bound [375, 203, 204] and G protein-bound A2A adenosine receptors [49] have been described. The structures of an antagonist-bound A1 receptor [128] and an adenosine-bound A1 receptor-Gi complex [86] have been resolved by cryo-electronmicroscopy. Another structure of an antagonist-bound A1 receptor obtained with X-ray crystallography has also been reported [57]. caffeine is a nonselective antagonist for adenosine receptors, while istradefylline, a selective A2A receptor antagonist, is on the market for the treatment of Parkinson's disease
Adenosine receptors (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database
Adenosine receptors (nomenclature as agreed by the NC-IUPHAR Subcommittee on Adenosine Receptors [103]) are activated by the endogenous ligand adenosine (potentially inosine also at A3 receptors). Crystal structures for the antagonist-bound [146, 305, 213, 55], agonist-bound [362, 196, 198] and G protein-bound A2A adenosine receptors [43] have been described. The structures of an antagonist-bound A1 receptor [123] and an adenosine-bound A1 receptor-Gi complex [80] have been resolved by cryo-electronmicroscopy. Another structure of an antagonist-bound A1 receptor obtained with X-ray crystallography has also been reported [51]
Adenosine receptors in GtoPdb v.2023.1
Adenosine receptors (nomenclature as agreed by the NC-IUPHAR Subcommittee on Adenosine Receptors [112]) are activated by the endogenous ligand adenosine (potentially inosine also at A3 receptors). Crystal structures for the antagonist-bound [155, 316, 224, 62], agonist-bound [379, 205, 206] and G protein-bound A2A adenosine receptors [49] have been described. The structures of an antagonist-bound A1 receptor [130] and an adenosine-bound A1 receptor-Gi complex [87] have been resolved by cryo-electronmicroscopy. Another structure of an antagonist-bound A1 receptor obtained with X-ray crystallography has also been reported [58]. The structure of the A2B receptor has also been elucidated [57]. caffeine is a nonselective antagonist for adenosine receptors, while istradefylline, a selective A2A receptor antagonist, is on the market for the treatment of Parkinson's disease
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A Body of Knowledge and Pedagogy for Global Engineering
Global engineers must be taught to consider the historical and present causes of persistent poverty and systematic barriers to prosperity. Such training will better inform the choices engineers make and help move the engineering sector away from a product and community-level focus towards working to address the root causes of poverty. A framing for Global Engineering has recently been proposed by the Mortenson Center in Global Engineering at the University of Colorado Boulder, building on over 15 years of curricular efforts. Global Engineering, as taught by the Mortenson Center, positions the field as a complement to Global Health and Development Economics while further embracing a historically contextualized and anti-colonial training.
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