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Carmen Marchiori Susan Stratton Sayre Leo K. Simon 《Water Resources Management》2012,26(10):2799-2816
Governments are increasingly reliant on the reacquisition of water rights as a mechanism for recovering overexploited basins. Yet, serious concerns have recently been raised about the efficacy and operational dimensions of existing programs. Water buyback is typically implemented as the purchase of a fixed quantity of water rights from the agricultural sector at the price set by the Water Authority. This paper seeks to analyze whether the use of water buyback in its current form represents a sensible means of recovering overexploited basins. The results??which are particularly relevant to contexts characterised by poor enforcement regimes and widespread illegal water use??highlight the need for greater scrutiny of current programs and call for additional work to improve the design of reacquisition policies in the context of water resource management. 相似文献
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This paper provides an overview of the challenge of spatial reconfiguration facing South Africa. Set against a brief overview of the key aspects of the post apartheid urban policy milieu that, notwithstanding significant tensions within the ruling party, gave rise to a cabinet level policy commitment to a National Spatial Development Perspective (NSDP). The paper reflects on three key themes. The first issue outlined in the paper is the massive demographic shift that is taking place that underpins the development challenge. In particular trends in the process of population growth, labour market change and urbanization are summarized. Second, given the dominance of Africans in urban spaces, the paper outlines how efforts to achieve racial integration have erroneously focused on rural over urban development. A distinction is drawn between traditionalist pro-African views that give preferences to rural spending and modernist views that articulate an overly non-racial discourse that embraces a shift to urban development. Finally we argue that the failure of spatial planning as proposed by the NSDP was not inevitable, despite real flaws in the policy and its execution. The dithering on spatial policy that surrounded the NSDP must be understood as the outcome of political contestation within the ruling party and a misplaced conflation of the categories of rural and African. 相似文献
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Objective: Interventions are increasingly described as theory-based; however, the basis for this is often not clear. Advancing behavioral science requires a good understanding of how interventions are informed by, and test, theory. This study aims to develop a reliable method for assessing the extent to which behavioral interventions are theory-based. Design: The reliability, usability, and comprehensiveness of an initial coding scheme were improved in 13 iterative stages on the basis of its application to 29 papers, from a systematic review of interventions to promote physical activity and healthy eating. Results: The final Theory Coding Scheme contained 19 items, each with satisfactory interrater reliabilities, coding whether a theory or model was mentioned, how theories were used in intervention design, how intervention evaluations tested theory, and the implications of the results for future theory development. Conclusion: The Theory Coding Scheme is an important methodological innovation, providing a research tool to reliably describe the theoretical base of interventions, inform evidence syntheses within literature reviews and meta-analyses, and stimulate the use of empirical data for theory development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
187.
Overview of Human Factors and Ergonomics in the OR,with an Emphasis on Minimally Invasive Surgeries
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Operating rooms (OR) are where medical teams work to improve the health of a patient. However, because of the complexity of the procedures, errors and unsafe situations are likely to occur. These complications can lead to harm to the patient or medical professionals. Human factors and ergonomic professionals have been working to improve these unsafe conditions in the OR for over a century. However, with advances in technology, increased surgical complexity, as well as an increase in medical team members in the OR, there are still numerous improvements yet to be accomplished. Minimally invasive surgeries require an even more advanced approach to prevent errors due to technology, fatigue, and miscommunication. Human factors and ergonomic techniques provide the ability to greatly improve conditions for patients and surgeons alike. It is imperative that human factors and ergonomics continue to grow and facilitate technological advancements in healthcare. © 2012 Wiley Periodicals, Inc. 相似文献
188.
Quaggin SE 《Microscopy research and technique》2002,57(4):208-211
189.
Three new electrodes were prepared by incorporating two different charge-transfer complexes and amino crown ether into plasticized PVC membranes. The electrodes showed Nernstian response to triiodide ion over the activity range from 1.0 x 10(-5) to 1.0 x 10(-1) mol x L(-1) with detection limits at approximately 1.0 x 10(-6) mol x L(-1). The resulting electrodes have fast response times (20-30 s) and good stabilities (4 months) and can be used over a wide pH range of 2.5-9.0. The proposed electrodes exhibit anti-Hofmeister behavior with excellent selectivity toward triiodide ion against a wide range of common interferences. Comparative study suggests that amino (aza) crown ether alone or in the form of a charge-transfer complex with iodine, as an ionophore in a PVC liquid membrane, is sensitive to triiodide ion. The electrodes were used as indicator electrodes in potentiometric titration of triiodide ion against thiosulfate ion. 相似文献
190.
In-channel electrochemical detection for microchip capillary electrophoresis using an electrically isolated potentiostat 总被引:3,自引:0,他引:3
A new electrode configuration for microchip capillary electrophoresis (CE) with electrochemical (EC) detection is described. This approach makes it possible to place the working electrode directly in the separation channel. The "in-channel" EC detection was accomplished without the use of a decoupler through the utilization of a specially designed, electrically isolated potentiostat. The effect of the working electrode position on the separation performance (in terms of plate height and peak skew) of poly(dimethylsiloxane)-based microchip CEEC devices was evaluated by comparing the more commonly used end-channel configuration with this new in-channel approach. Using catechol as the test analyte, it was found that in-channel EC detection decreased the total plate height by a factor of 4.6 and lowered the peak skew by a factor of 1.3. A similar trend was observed for the small, inorganic ion nitrite. Furthermore, a fluorescent and electrochemically active amino acid derivative was used to directly compare the separation performance of in-channel EC detection to that of a widely used laser-induced fluorescence (LIF) detection scheme. In this case, it was found that the plate height and peak skew for both detection schemes were essentially equal, and the separation performance of in-channel EC detection is comparable to LIF detection. 相似文献