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21.
Our fundamental premise is that energy consumption at the household level is a key indicator of standard of living. We employ state-of-the-art panel cointegration techniques to evaluate the nature of the relationship between income measures and energy consumption measures for seven East Indian Ocean countries. The general finding is that income and household electricity consumption are not cointegrated. Given this finding, we conclude that standard of living measures that rely on income measures and do not include household-level energy consumption information will necessarily miss important indications of both levels and changes of standard of living. 相似文献
22.
Optical isomer separation by liquid chromatography 总被引:1,自引:0,他引:1
D W Armstrong 《Analytical chemistry》1987,59(2):84A-91A
23.
Boesch Ronald D. Magin Richard L. Franke Stevenb J. 《IEEE transactions on bio-medical engineering》1987,(11):904-907
This paper describes a design for an analog phase shifter operating at 915 MHz and suitable for use in a phased array microwave hyperthermia system. Here, the major operating constraint was minimization of amplitude variation over a 1800 phase shift, whereas previous phase shifters were designed to obtain a linear relationship between phase and control voltage. The result is a simple, inexpensive hybrid coupler phase shifter that operates over a narrow bandwidth and provides 180°of continuous phase shift with input powers up to 1 W. 相似文献
24.
25.
Ronald Smith 《Canadian Metallurgical Quarterly》2004,130(2):165-169
For longitudinally uniform stretches of waterways there is a mixing center for the across-channel location of a steady point source in steady flow, such that complete mixing is achieved as soon as possible and there is no concentration overshoot at either of the two shorelines. A mathematical definition of the mixing center is the zero of the first oscillatory cross-channel diffusion mode. With the shorelines plus four interior data points across the channel, the starting estimate for the mixing center suffices to keep peak shoreline concentrations to within 6% of optimal. For comparison, a source at mid flow gives 18% shoreline concentration overshoot in the test case. Should very high precision be required, the Appendix gives an iterative construction that converges to the first oscillatory diffusion mode. 相似文献
26.
This study investigated the relationship between self-appraisals of performance, symptom severity and post-event rumination in social phobia, and evaluated the effect of treatment on these variables. A socially phobic group and a nonanxious control group performed an impromptu speech and were told that their performance would be evaluated. Participants appraised their performance immediately after the speech and 1 week later, and the frequency of post-event rumination during the week following the speech was assessed. The socially phobic group maintained the negative appraisals of their speech over the week, whereas the nonclinical group showed increased positivity about their performance The socially phobic group also engaged in more negative rumination than controls. Treatment improved perceptions of performance and reduced negative rumination. These results are discussed in the light of cognitive models of social phobia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
27.
Summary Sedimentation experiments and X-ray photoelectron spectroscopy (XPS or ESCA) analyses have been used to study the effect of poly(methylmethacrylate) (PMMA) tacticity on aluminum oxide powder dispersion stability in a common solvent medium. The relative trends from sedimentation densities, and from surface analyses after solvent washing show that (PMMA) adsorption is greatest with isotactic polymer, where isotactic>atactic>syndiotactic adsorption. These results suggest that surface adsorption and hence dispersion stability can be influenced by polymer chain configuration as well as by chain conformation. 相似文献
28.
Various ways of quantifying damages have been applied to productivity loss claims in construction. All of the ways attempt to be as objective as possible based on the extent of information available in a particular case. The measured mile, a widely accepted method, is employed when an unimpacted baseline period of production can be identified. Although that approach is considered to be the most objective method available in such cases, the method is limited and does not directly account for variation in individual productivity values about a normal or natural level of productivity. A gap exists between the use of existing methods and the availability of an appropriate methodology that specifically addresses variation in productivity. The key lies in the way baseline productivity is measured, which is inherently statistical, yet no truly statistical methods are used to establish such a baseline. Using the measured mile as a backdrop, this article provides an objective, measurement-based approach that can be used to establish a productivity baseline applied to construction productivity loss claims, based on the application of statistical methods aided by a process control chart. The focus is on providing the basic principles and concepts underlying the approach presented. 相似文献
29.
Although adenosine receptors have been implicated in the induction of preconditioning in a variety of experimental models, there is controversy concerning the specific adenosine receptor subtypes mediating this effect. Concentration-protection relationships for adenosine and adenosine agonists in rabbit cardiomyocytes were used to characterize the role of adenosine receptor subtypes in preconditioning. Isolated cells were ischemically preconditioned or pre-incubated for 10 min with increasing concentrations of adenosine, CCPA (2-chloro-N6-cyclopentyladenosine), APNEA (N6-2-(4-aminophenyl)ethyladenosine), or BNECA (N6-benzyl-5'-N-ethyl-carboxamidoadenosine) in the presence or absence of 1 or 10 microM of the selective A1-adenosine antagonist DPCPX (8-Cyclopentyl-1,3-dipropylxanthine). Following a 30-min post-incubation period, cells were pelleted, layered with oil and ischemically incubated for 180 min. Injury was assessed by osmotic swelling and trypan blue exclusion of sequential samples, and determination of the areas beneath the mortality curves. Adenosine produced a broad concentration-protection curve which was displaced to the right by DPCPX. The curve for A1-selective agonist CCPA was biphasic, with an initial response below 1 nM and a second above 1 microM. DPCPX abolished the early response leaving a steep monophasic curve between 0.1 and 10 microM CCPA. The APNEA curve appeared moriophasic, the major slope occurring between 1-100 nM; DPCPX (1 microM) shifted the concentration-response curve approximately 30-fold and decreased the slope. Adenosine receptor agonist BNECA produced preconditioning characterized by a shallow monophasic concentration-protection curve with a maximal effect of 49% and an EC50 of approximately 5 nM; DPCPX shifted the BNECA concentration-protection relationship approximately 40-fold with only a modest increase in slope. Analysis of the data suggests that induction of preconditioning results from interaction of agonists with the A1 receptor and a second adenosine receptor having properties consistent with the A3 receptor. Adenosine, CCPA, APNEA, BNECA and DPCPX each appear to be selective for the A1 adenosine receptor subtype in isolated rabbit cardiomyocytes. 相似文献
30.
AB Thomson N Chiba D Armstrong G Tougas RH Hunt 《Canadian Metallurgical Quarterly》1998,12(8):551-556
Gastroesophageal reflux disease (GERD) is a disease with serious consequences that may result in significant impairment in quality of life and disease morbidity. Across all grades of severity of symptoms and severity of underlying esophageal disease, proton pump inhibitors (PPIs) provide therapeutic gains over prokinetics (PKs) or H2 receptor antagonists (H2RAs). The potential cost effectiveness of using medications with higher acquisition costs that may lower health care costs overall is often disregarded when conducting cost comparisons with medications having lower 'up-front' costs. Limiting therapy to less effective agents condemns many patients to protracted suffering, repeated physician visits and needless reinvestigation of symptoms that could have been resolved by appropriate initial therapy. Based on current data, use of any classification of symptom severity as a basis for selecting one class of therapeutic agents over another for first line therapy (i.e. PKs, H2RAs for 'mild' GERD, versus a PPI for 'severe' disease) is unwarranted. 相似文献