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851.
Static magnetic field (SMF) therapy delivered by permanent magnets is being used as a self-care intervention by millions of
people worldwide, despite a paucity of clinical research confirming or refuting therapeutic effectiveness. Evaluating the
reported results of SMF clinical trials is difficult because researchers use heterogeneous dosing regimens, unreliable sham
controls, and questionable blinding strategies. Three important methodological challenges need to be contended with when conducting
and interpreting SMF studies: optimization of SMF dosimetry, use of a believable physiologically inert sham, and assurance
of participant blinding in unsupervised settings. Our objectives in writing this review are to describe ten essential SMF
dosing parameters that need to be reported in SMF clinical trials and to discuss sham controls and blinding procedures for
SMF studies. 相似文献
852.
We propose to bridge the domains of positive health and leadership. We suggest that a “positive” health model helps explain highly effective leadership. The leader must strive for health and facilitate health in his/her followers. We look at leadership through this new and positive lens, that of “positive” health promotion. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
853.
James J. Lavelle Joel Brockner Mary A. Konovsky Kenneth H. Price Amy B. Henley Aakash Taneja Vishnu Vinekar 《组织行为杂志》2009,30(3):337-357
Research on commitment, procedural fairness, and organizational citizenship behavior (OCB) suggests that employees maintain distinct beliefs about, and direct behaviors towards, multiple targets in the workplace (e.g., the organization as a whole, their supervisor, and fellow workgroup members). The present studies were designed to test for “target similarity effects,” in which the relationships between commitment, procedural fairness, and OCB were expected to be stronger when they referred to the same target than when they referred to different targets. As predicted, we found that: (1) the positive relationship between commitment and OCB, and (2) the mediating effect of commitment on the positive relationship between procedural fairness and OCB, was particularly likely to emerge when the constructs were in reference to the same target. Support for these target similarity effects was found among layoff survivors (Study 1) and student project teams (Study 2). Theoretical and practical implications are discussed, as are limitations of the studies and suggestions for future research. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
854.
Liem T. Tran C. Gregory Knight Robert V. O'Neill Elizabeth R. Smith Kurt H. Riitters James Wickham 《Environmental management》2001,29(6):845-859
A fuzzy decision analysis method for integrating ecological indicators was developed. This was a combination of a fuzzy ranking method and the analytic hierarchy process (AHP). The method was capable of ranking ecosystems in terms of environmental conditions and suggesting cumulative impacts across a large region. Using data on land cover, population, roads, streams, air pollution, and topography of the Mid-Atlantic region, we were able to point out areas that were in relatively poor condition and/or vulnerable to future deterioration. The method offered an easy and comprehensive way to combine the strengths of fuzzy set theory and the AHP for ecological assessment. Furthermore, the suggested method can serve as a building block for the evaluation of environmental policies. 相似文献
855.
Negotiation for permitting and regulatory compliance of energy facilities typically involves complex decision making over multiple planning horizons involving several organizations with possibly competing goals. Delays in compliance negotiation have the potential to undermine or deter the ability for countries and agencies to increase energy capacities and improve overall energy security. There is need for a multi-scale modeling framework with recognition of multiple time horizons, geographies, and organizational entities influencing the system. This paper presents a multi-scale analysis of the review and permitting process for repeated stages of interaction between a private energy operator and an energy regulatory agency. The interaction is modeled as a finitely repeated incomplete information game with identification of steady-state equilibrium conditions. The result is a strategy-guiding tool that can be used to identify potential incentives for cooperation among a variety of decision makers including energy policy decision makers, regulatory agencies, and project developers. The tools are described via a simplified demonstration applied to the permitting of liquefied natural gas terminals in various stages of their lifecycle. There is wide applicability for regulation, approval, deployment, and monitoring of infrastructure and environment in the energy industry. 相似文献
856.
Walter J. Hamming Robert D. Macphee James R. Taylor 《Journal of the Air & Waste Management Association (1995)》2013,63(1):7-16
Sampling for nitrogen and sulfur dioxides was initiated at several National Air Sampling Network stations in 1959 using a sampler developed for that purpose. In 1961 the Gas Sampling Network was expanded to its maximum of 49 stations. Sampling equipment and collecting solutions are supplied and chemical analyses performed by the network laboratories. Sampling and analysis procedures are described briefly. Average and maximum 24-hour concentrations of nitrogen dioxide and sulfur dioxide observed at 48 stations during 1961-1963 are presented. 相似文献
857.
Joseph P. Reynolds Louis Theodore James Marino 《Journal of the Air & Waste Management Association (1995)》2013,63(6):610-616
The body of information presented In this paper is directed to those Individuals involved In research on, or the design of, electrostatic precipitators. A model for calculating collection efficiencies— one based solely on physical principles and, as a result, one requiring no prior Information from pilot plant or field testing—has been employed to generate performance curves for twelve Industries presently using electrostatic precipitators. These industries Include the electric power, cement, pulp and paper, steel, chemical, and petroleum industries. The performance curves describe the predicted collection efficiency as a function of preclpltator length, plate-to-plate spacing and average field strength, and are presented In graphical, tabular, and equation form. Wherever literature values for a particular Industry are available, comparisons are made between the collection efficiencies generated by the new model and those based on actual preclpltator performance. The two are generally found to be In reasonable agreement. The use of the Deufsch-Anderson model for preclpltator design Is also discussed. Results from the new model demonstrate that collection efficiency Is sensitive to particle size distribution, a complication that cannot be easily treated In the Deutsch-Ander-son equation which, In Its unmodified form, requires the use of a single representative particle size. It is concluded that the new model Is potentially a more realistic and viable approach to the prediction of collection efficiencies and as such should prove to be a valuable aid in electrostatic preclpltator design. 相似文献
858.
C. Andrew James Gang Xin Sharon L. Doty Indulis Muiznieks Lee Newman Stuart E. Strand 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2564-2569
A mass balance study was performed under controlled field conditions to investigate the phytoremediation of perchloroethylene (PCE) by hybrid poplar trees. Water containing 7–14 mg L?1 PCE was added to the test bed. Perchloroethylene, trichloroethylene, and cis-dichloroethylene were detected in the effluent at an average of 0.12 mg L?1, 3.9 mg L?1, and 1.9 mg L?1, respectively. The total mass of chlorinated ethenes in the water was reduced by 99%. Over 95% of the recovered chlorine was as free chloride in the soil, indicating near-complete dehalogenation of the PCE. Transpiration, volatilization, and accumulation in the trees were all found to be minor loss mechanisms. In contrast, 98% of PCE applied to an unplanted soil chamber was recovered as PCE in the effluent water or volatilized into the air. These results suggest that phytoremediation can be an effective method for treating PCE-contaminated groundwater in field applications. 相似文献
859.
Rebecca Efroymson Henriette Jager Virginia Dale James Westervelt 《Environmental management》2009,44(6):1163-1179
A decision framework for setting management goals for species at risk is presented. Species at risk are those whose potential
future rarity is of concern. Listing these species as threatened or endangered could potentially result in significant restrictions
to activities in resource management areas in order to maintain those species. The decision framework, designed to foster
proactive management, has nine steps: identify species at risk on and near the management area, describe available information
and potential information gaps for each species, determine the potential distribution of species and their habitat, select
metrics for describing species status, assess the status of local population or metapopulation, conduct threat assessment,
set and prioritize management goals, develop species management plans, and develop criteria for ending special species management
where possible. This framework will aid resource managers in setting management goals that minimally impact human activities
while reducing the likelihood that species at risk will become rare in the near future. The management areas in many of the
examples are United States (US) military installations, which are concerned about potential restrictions to military training
capacity if species at risk become regulated under the US Endangered Species Act. The benefits of the proactive management
set forth in this formal decision framework are that it is impartial, provides a clear procedure, calls for identification
of causal relationships that may not be obvious, provides a way to target the most urgent needs, reduces costs, enhances public
confidence, and, most importantly, decreases the chance of species becoming more rare. 相似文献
860.