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1.
Abstract

In this day and age, it is widely argued that stakeholder engagement in water-related decision-making processes yields many benefits, including legitimacy, acceptance and trust. Key legal frameworks, such as the European Water Framework Directive and the Aarhus Convention, have spurred the emergence of formal forms of stakeholder engagement. On the other hand, many engagement processes are spontaneous and self-organized. This article investigates the strategies used in formal (government-led) and informal (bottom-up) engagement processes in search of a middle ground. To this end, case studies in the Netherlands, the United States, Uganda and Ethiopia are analyzed using the OECD’s stakeholder engagement checklist. We conclude with reflection on the ways forward to make formal and informal stakeholder engagement complementary.  相似文献   
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BACKGROUND: Climacteric fruits are harvested at the green‐mature stage and ripen during their marketing cycle. However, growing conditions induce variability into the maturity stage of mangoes at harvest, with an impact on their final quality. Assuming that the physiological age can be correctly evaluated by a criterion based on the variable chlorophyll fluorescence of the skin (Fv) and that differences in physiological age depend on growing conditions, controlled stress experiments were carried out on mango fruit by manipulating either the leaf/fruit ratio or the light environment. RESULTS: Delays from 9 to 30 days were observed, depending on stress level and harvest stage, to obtain the same Fv value. For moderate stress, fruit composition after ripening was partially compensated for, with little or no difference in sugar, dry matter, carotenoid and aroma contents. For more pronounced stress, the major metabolites were not particularly affected, but the synthesis capacity of carotenoids and aromas was lower after maturity. CONCLUSION: The ripening ability of a fruit is acquired on the tree and defines its postharvest changes. Control of the physiological age at harvest can minimise the variability observed under natural conditions and guarantee fruit batches whose postharvest changes will be relatively homogeneous. Copyright © 2011 Society of Chemical Industry  相似文献   
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ABSTRACT

Engaging marginalised children, such as disabled children, in Participatory Design (PD) entails particular challenges. The processes can effect social changes by decidedly attending to their lived experience as expertise. However, involving marginalised children in research also requires maintaining a delicate balance between ensuring their right to participation as well as their protection from harm. The resulting tensions are politically charged, affected by myriads of power differences and create moral dilemmas. We present seven case studies, drawing from two participatory design research projects. They illustrate the in-situ judgements taken to address specific dilemmas and provide nuanced insights into the trade-offs required by child-led participatory design processes. Subsequently, we identify three challenges: positioning our work to the children’s carers’ values, protecting ourselves, and enabling the (relative) risk-taking associated with participation for children. We call for this micro-ethical approach to be used when reporting research ethics in practice, and as a guidance for the training of researchers and practitioners.  相似文献   
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Oleic acid (OA) is a renewable monounsaturated fatty acid obtained from high oleic sunflower oil. This work was focused on the oxidative scission of OA, which yields a mono-acid (pelargonic acid, PA) and a di-acid (azelaic acid, AA) through an emulsifying system. The conventional method for producing AA and PA consists of the ozonolysis of oleic acid, a process which presents numerous drawbacks. Therefore, we proposed to study a new alternative process using a green oxidant and a solvent-free system. OA was oxidized in a batch reactor with a biphasic organic-aqueous system consisting of hydrogen peroxide (H2O2, 30 %) as an oxidant and a peroxo–tungsten complex Q3{PO4[WO(O2)2]4} as a phase-transfer catalyst/co-oxidant. Several phase-transfer catalysts were prepared in situ from tungstophosphoric acid, H2O2 and different quaternary ammonium salts (Q+, Cl). The catalyst [C5H5N(n-C16H33)]3{PO4[WO(O2)2]4} was found to give the best results and was chosen for the optimization of the other parameters of the process. This optimization led to a complete conversion of OA into AA and PA with high yields (>80 %) using the system OA/H2O2/[C5H5N(n-C16H33)]3{PO4[WO(O2)2]4} (1/5/0.02 molar ratio) at 85 °C for 5 h. In addition, a new treatment was developed in order to recover the catalyst.  相似文献   
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Amorphous Ge–Sb–Se thin films were fabricated by a rf‐magnetron co‐sputtering technique employing the following cathodes: GeSe2, Sb2Se3, and Ge28Sb12Se60. The influence of the composition, determined by energy‐dispersive X‐ray spectroscopy, on the optical properties was studied. Optical properties were analyzed based on variable angle spectroscopic ellipsometry and UV‐Vis‐NIR spectrophotometry. The results show that the optical bandgap range 1.35‐2.08 eV with corresponding refractive index ranging from 3.33 to 2.36 can be reliably covered. Furthermore, morphological and topographical properties of selenide‐sputtered films studied by scanning electron microscopy and atomic force microscopy showed a good quality of fabricated films. In addition, structure of the films was controlled using Raman scattering spectroscopy. Finally, irreversible photoinduced changes by means of change in optical bandgap energy and refractive index of co‐sputtered films were studied revealing the photobleaching effect in Ge‐rich films when irradiated by near‐bandgap light under Ar atmosphere. The photobleaching effect tends to decrease with increasing antimony content.  相似文献   
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Pulsed laser deposition was used to prepare amorphous thin films from (GeSe2)100?x(Sb2Se3)x system (x = 0, 5, 10, 20, 30, 40, 50, and 60). From a wide variety of chalcogenide glass‐forming systems, Ge–Sb–Se one, especially in thin films form, already proved to offer a great potential for photonic devices such as chemical sensors. This system has a large glass‐forming region which gives the possibility to adjust the chemical composition of the glasses according to required physical characteristics. The chemical composition of fabricated thin films was analyzed via X‐ray photoelectron spectroscopy (XPS) and compared to energy dispersive spectroscopy (EDS) data. The results of both techniques agree well: a small deficiency in chalcogen element and an excess of antimony was found. The structure of as‐deposited thin films has been investigated by XPS. The presence of the two main structural units, [GeSe4] and [SbSe3] proposed by Raman scattering spectroscopy data analysis, was confirmed by XPS. Moreover, XPS core level spectra analysis revealed the presence of M–M bonds (M = Ge, Sb) in (Ge,Sb)–Ge–(Se)3 and (Ge,Sb)–Sb–(Se)2 entities that could correspond to Ge‐based tetrahedra and Sb‐based pyramids where one of its Se atoms at corners is substituted by Ge or Sb ones. The content of depicted M–M bonds tends to increase with introduction of antimony in the amorphous network of as‐deposited thin films from x = 0 to x = 40 and then it decreases. XPS analysis of as‐deposited thin films shows also the presence of the (Ge,Sb)–Se–(Ge,Sb) and Se–Se–(Ge,Sb) entities.  相似文献   
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Cell membranes exhibit elaborate lipidic patterning to carry out a myriad of functions such as signaling and trafficking. Domain formation in giant unilamellar vesicles (GUVs) is thus of interest for understanding fundamental biological processes and to provide new prospects for biocompatible soft materials. Lipid rearrangements in lipidic GUVs and lipid/polymer GUVs are extensively studied whereas polymer/polymer hybrid GUVs remain evasive. Here, the focus is on the thermodynamically driven phase separation of amphiphilic polymers in GUVs. It is demonstrated that polymer phase separation is entropically dictated by hydrophobic block incompatibilities and that films topology can help to determine the outcome of polymeric phase separation in GUVs. Lastly, Janus‐GUVs are obtained and GUVs exhibit a single large domain by using a compatibilizing hydrophobic block copolymer.  相似文献   
10.
Software and Systems Modeling - Enterprise systems are growing in complexity, and the adoption of cloud and mobile services has greatly increased the attack surface. To proactively address these...  相似文献   
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