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81.
Water Resources Management - A traditional cost-benefit analysis of potential water interventions in a given locality is a laborious and time-intensive process. To help decision makers identify...  相似文献   
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A conventional cumulative sum control chart has a V‐mask where each arm makes an angle θ with the horizontal and has a lead distance d. These parameters are usually related to h (=dA tan(?), A is a scaling factor) and k(=A tan(?)). Two systems of formulas are examined for deriving h and k for selected values of the in control and out of control average run lengths. This is the first time an exhaustive comparison has been made. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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Diamond Light Source (Diamond) utilises a large number of Inverted Magnetron Gauges (IMGs) for both monitoring the vacuum and as a source of interlocks for protection of the machine. During storage ring operation it has been found that, in the presence of the stored electron beam, charged particles, assumed to be electrons, impinging on some of the gauges cause the pressures indicated by the gauges to drop to zero which causes problems with the operation of the storage ring. Diamond has designed and fitted a magnetic filter at the neck of each affected gauge port to eliminate this problem. This paper reports on and discusses experiments and proposed experiments with an electron flood gun and IMGs from two different manufacturers (MKS Instruments and Pfeiffer Vacuum) aimed at obtaining a better understanding of the effect. Externally-generated electrons from the flood gun can cause serious errors in the pressures indicated by the gauges; the error can be positive or negative depending on the gauge current-measuring circuit. Methods aimed at eliminating these spurious pressure readings, such as magnetic filters, bias voltages within the gauges and the use of earth meshes and baffles are also discussed.  相似文献   
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A pentaerythritol-based metallodendrimer with RuIIterpyridine units was synthesized and tested as a mediator for the electrochemical oxidation of methionine (L-Met), cystine (L-Cys), and AsIII. A reversible oxidation of RuII was observed with the metallodendrimer as a solute in mixed acetonitrile-water solvents and as a component of carbon-based conducting composite electrodes. Mediated oxidation of the test species was observed. In aqueous solution, the composite electrode yielded a cyclic voltammetric peak current for the oxidation of L-Met in a 0.1 M phosphate buffer (pH 7.0) at 1.1 V vs Ag/AgCl. This anodic process was employed for amperometric detection in a flow system. Linear calibration curves were obtained over the range 1.0-10 microM Met and Cys. Using the criterion of the concentration yielding a signal 3 times the uncertainty of a blank, detection limits of 0.6 and 0.5 microM were calculated for Met and Cys, respectively. The slopes with three nominally identical electrodes varied by 10%.  相似文献   
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Decisions about using addictive substances are influenced by distractions by addiction-related stimuli, of which the user might be unaware. The addiction-Stroop task is a paradigm used to assess this distraction. The empirical evidence for the addiction-Stroop effect is critically reviewed, and meta-analyses of alcohol-related and smoking-related studies are presented. Studies finding the strongest effects were those in which participants had strong current concerns about an addictive substance or such concerns were highlighted through experimental manipulations, especially those depriving participants of the substance. Theories to account for addiction-related attentional bias are discussed, of which the motivational theory of current concerns appears to provide the most complete account of the phenomenon. Recommendations are made for maximizing the precision of the addiction-Stroop test in future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The adult cuticular wing of Drosophila is covered by an array of distally pointing hairs that reveals the planar polarity of the wing. We report here that mutations in dachsous disrupt this regular pattern, and do so by affecting frizzled signaling. dachsous encodes a large membrane protein that contains many cadherin domains and dachsous mutations cause deformed body parts. We found that mutations in dachsous also result in a tissue polarity phenotype that at the cellular level is similar to frizzled, dishevelled and prickle, as many cells form a single hair of abnormal polarity. Although their cellular phenotype is similar to frizzled, dishevelled and prickle, dachsous mutant wings display a unique and distinctive abnormal hair polarity pattern including regions of reversed polarity. The development of this pattern requires the function of frizzled pathway genes suggesting that in a dachsous mutant the frizzled pathway is functioning - but in an abnormal way. Genetic experiments indicated that dachsous was not required for the intracellular transduction of the frizzled signal. However, we found that dachsous clones disrupted the polarity of neighboring wild-type cells suggesting the possibility that dachsous affected the intercellular signaling function of frizzled. Consistent with this hypothesis we found that frizzled clones in a dachsous mutant background displayed enhanced domineering non-autonomy, and that the anatomical direction of this domineering non-autonomy was altered in regions of dachsous wings that have abnormal hair polarity. The direction of this domineering nonautonomy was coincident with the direction of the abnormal hair polarity. We conclude that dachsous causes a tissue polarity phenotype because it alters the direction of frizzled signaling.  相似文献   
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