585 research outputs found

    Reducing or increasing inequalities? The role of private water enterprises in rural Viet Nam

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    Extreme inequalities are recognised as being detrimental to human rights and economic development (Stiglitz 2012), and in response, the 2030 Agenda for Sustainable Development has explicitly included addressing inequalities as one of the 17 Global Goals. In order to reduce inequalities an integrated approach across multiple dimensions of human development is required, including access to safe water. This research investigated stakeholder perceptions of rural piped water services in Viet Nam to better understand issues of equality, access and affordability. It asked the question: can poor households access piped water services provided by small scale private enterprises in rural Viet Nam? This question is important because little is known about whether or not poor households access piped water services, related issues of affordability of connection fees and tariffs, and other potential barriers. It is also important because private enterprises are increasingly providing piped water services in Viet Nam, supported by incentives from Government and international donors including some civil society organisations (CSOs

    Nanofiltration applications of tough MWNT buckypaper membranes containing biopolymers

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    © 2017 Elsevier B.V. The ability of biopolymers (bovine serum albumin, lysozyme, chitosan, gellan gum and DNA) to facilitate formation of aqueous dispersions of MWNTs was investigated using a combination of absorption spectrophotometry and optical microscopy. Subsequently, self-supporting carbon nanotube membranes, known as buckypapers (BPs), were prepared by vacuum filtration of the dispersions. Microanalytical data obtained from the BPs confirmed the retention of biopolymers within their structures. Tensile test measurements performed on the BPs showed that incorporation of the biopolymers resulted in significant improvements in mechanical properties, compared to analogous BPs containing MWNTs and the low molecular mass dispersant Triton X-100. For example, MWNT/CHT BPs (CHT=chitosan) exhibited values for tensile strength, ductility, Young's modulus and toughness of 28±2 MPa, 5.3±2.7%, 0.9±0.3 GPa and 1.7±0.3 J g−1, respectively. Each of these values are significantly greater than those obtained for MWNT/Trix BPs, prepared using a low molecular weight dispersant (6±3 MPa, 1.3±0.2%, 0.6±0.3 GPa and 0.10±0.06 J g−1, respectively). This significant improvement in mechanical properties is attributed to the ability of the long biopolymer molecules to act as flexible bridges between the short CNTs. All BPs possessed hydrophilic surfaces, with contact angles ranging from 29±2° to 57±5°. Nitrogen gas porosimetry showed that the BPs have highly porous internal structures, while scanning electron microscopy (SEM) showed their surface morphologies have numerous pore openings. The permeability of the BPs towards water, inorganic salts, and dissolved trace organic contaminants (TrOCs), such as pharmaceuticals, personal care products, and pesticides, was investigated through filtration experiments. Of the twelve TrOCs investigated in this study, nine were rejected by more than 95% by BPs composed of MWNTs and chitosan. The latter BPs also demonstrated good rejection of both NaCl (30–55%) and MgSO4(40–70%)

    A Novel Approach in Crude Enzyme Laccase Production and Application in Emerging Contaminant Bioremediation

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    Laccase enzyme from white-rot fungi is a potential biocatalyst for the oxidation of emerging contaminants (ECs), such as pesticides, pharmaceuticals and steroid hormones. This study aims to develop a three-step platform to treat ECs: (i) enzyme production, (ii) enzyme concentration and (iii) enzyme application. In the first step, solid culture and liquid culture were compared. The solid culture produced significantly more laccase than the liquid culture (447 vs. 74 µM/min after eight days), demonstrating that white rot fungi thrived on a solid medium. In the second step, the enzyme was concentrated 6.6 times using an ultrafiltration (UF) process, resulting in laccase activity of 2980 µM/min. No enzymatic loss due to filtration and membrane adsorption was observed, suggesting the feasibility of the UF membrane for enzyme concentration. In the third step, concentrated crude enzyme was applied in an enzymatic membrane reactor (EMR) to remove a diverse set of ECs (31 compounds in six groups). The EMR effectively removed of steroid hormones, phytoestrogen, ultraviolet (UV) filters and industrial chemical (above 90%). However, it had low removal of pesticides and pharmaceuticals.</jats:p

    Conséquences de l’évolution de l’occupation des sols sur les lacs et les rivières d’un bassin versant de moyenne montagne: application au bassin versant de l’Ain (France)

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    The Ain river – tributary of the Rhone, is distinguished by a geological and geomorphological duality splitting it into two very clear parts: the mountainous (karstic-jura mountains) and the low alluvial valley of the Ain river, characterized by agricultural land use. The geographical boundary between the two zones is the dam of Vouglans (3rd water reserve of France). These geological differences give rise to two types of reserves: karstic reserves at the top of the watershed and an alluvial water table enclosed in the quaternary alluvium at the bottom. The last thirty years have been marked by the massive exodus of the rural populations of the Haut, which maintained a pastoral activity for the valleys holding most of the industries. A renewal of pastoral areas by mainly coniferous and deciduous forests, particularly in the upper part of the catchment area (Jura), reflects this phenomenon of exodus. This process was accompanied by an increase in the input of organic matter and marked deoxygenation of the deep (hypolimnion) levels of the water bodies, mostly located at the top. This physico-chemical manifestation is felt at the bottom in rivers and more particularly in the river Ain, one of the main tributaries of the Rhone. The management of water resources has been subjected to this geological and economic duality, giving rise to a SWMM (Scheme for Water Management and Management) based on the alluvial plain in the lower part of the watershed and the installation of numerous contracts of rivers on the affluent of the Ain in addition to the SWMM. One of the priority concerns of managers is the assessment of the extent of deoxygenation recorded in the plans to the rivers and especially its consequences on the lower rivers. The results of measurements and models applied show that the phenomenon is not very noticeable upstream and downstream of the Vouglans dam. Predictive simulations incorporating the GIEC recommendations (optimistic and pessimistic scenario) do not show a particular trend for 2050.The Ain river – tributary of the Rhone, is distinguished by a geological and geomorphological duality splitting it into two very clear parts: the mountainous (karstic-jura mountains) and the low alluvial valley of the Ain river, characterized by agricultural land use. The geographical boundary between the two zones is the dam of Vouglans (3rd water reserve of France). These geological differences give rise to two types of reserves: karstic reserves at the top of the watershed and an alluvial water table enclosed in the quaternary alluvium at the bottom. The last thirty years have been marked by the massive exodus of the rural populations of the Haut, which maintained a pastoral activity for the valleys holding most of the industries. A renewal of pastoral areas by mainly coniferous and deciduous forests, particularly in the upper part of the catchment area (Jura), reflects this phenomenon of exodus. This process was accompanied by an increase in the input of organic matter and marked deoxygenation of the deep (hypolimnion) levels of the water bodies, mostly located at the top. This physico-chemical manifestation is felt at the bottom in rivers and more particularly in the river Ain, one of the main tributaries of the Rhone. The management of water resources has been subjected to this geological and economic duality, giving rise to a SWMM (Scheme for Water Management and Management) based on the alluvial plain in the lower part of the watershed and the installation of numerous contracts of rivers on the affluent of the Ain in addition to the SWMM. One of the priority concerns of managers is the assessment of the extent of deoxygenation recorded in the plans to the rivers and especially its consequences on the lower rivers. The results of measurements and models applied show that the phenomenon is not very noticeable upstream and downstream of the Vouglans dam. Predictive simulations incorporating the GIEC recommendations (optimistic and pessimistic scenario) do not show a particular trend for 2050

    Platelet-activating factor is crucial in psoralen and ultraviolet A-induced immune suppression, inflammation, and apoptosis.

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    Psoralen plus UVA (PUVA) is used as a very effective treatment modality for various diseases, including psoriasis and cutaneous T-cell lymphoma. PUVA-induced immune suppression and/or apoptosis are thought to be responsible for the therapeutic action. However, the molecular mechanisms by which PUVA acts are not well understood. We have previously identified platelet-activating factor (PAF), a potent phospholipid mediator, as a crucial substance triggering ultraviolet B radiation-induced immune suppression. In this study, we used PAF receptor knockout mice, a selective PAF receptor antagonist, a COX-2 inhibitor (presumably blocking downstream effects of PAF), and PAF-like molecules to test the role of PAF receptor binding in PUVA treatment. We found that activation of the PAF pathway is crucial for PUVA-induced immune suppression (as measured by suppression of delayed type hypersensitivity to Candida albicans) and that it plays a role in skin inflammation and apoptosis. Downstream of PAF, interleukin-10 was involved in PUVA-induced immune suppression but not inflammation. Better understanding of PUVA\u27s mechanisms may offer the opportunity to dissect the therapeutic from the detrimental (ie, carcinogenic) effects and/or to develop new drugs (eg, using the PAF pathway) that act like PUVA but have fewer side effects

    Sparing of the Dystrophin-Deficient Cranial Sartorius Muscle Is Associated with Classical and Novel Hypertrophy Pathways in GRMD Dogs

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    Both Duchenne and golden retriever muscular dystrophy (GRMD) are caused by dystrophin deficiency. The Duchenne muscular dystrophy sartorius muscle and orthologous GRMD cranial sartorius (CS) are relatively spared/hypertrophied. We completed hierarchical clustering studies to define molecular mechanisms contributing to this differential involvement and their role in the GRMD phenotype. GRMD dogs with larger CS muscles had more severe deficits, suggesting that selective hypertrophy could be detrimental. Serial biopsies from the hypertrophied CS and other atrophied muscles were studied in a subset of these dogs. Myostatin showed an age-dependent decrease and an inverse correlation with the degree of GRMD CS hypertrophy. Regulators of myostatin at the protein (AKT1) and miRNA (miR-539 and miR-208b targeting myostatin mRNA) levels were altered in GRMD CS, consistent with down-regulation of myostatin signaling, CS hypertrophy, and functional rescue of this muscle. mRNA and proteomic profiling was used to identify additional candidate genes associated with CS hypertrophy. The top-ranked network included α-dystroglycan and like-acetylglucosaminyltransferase. Proteomics demonstrated increases in myotrophin and spectrin that could promote hypertrophy and cytoskeletal stability, respectively. Our results suggest that multiple pathways, including decreased myostatin and up-regulated miRNAs, α-dystroglycan/like-acetylglucosaminyltransferase, spectrin, and myotrophin, contribute to hypertrophy and functional sparing of the CS. These data also underscore the muscle-specific responses to dystrophin deficiency and the potential deleterious effects of differential muscle involvement
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