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171.
Concern for the exposure of children attending schools located near busy roadways to toxic, traffic‐related air pollutants has raised questions regarding the environmental benefits of advanced heating, ventilation, and air‐conditioning (HVAC) filtration systems for near‐road pollution. Levels of black carbon and gaseous pollutants were measured at three indoor classroom sites and at seven outdoor monitoring sites at Las Vegas schools. Initial HVAC filtration systems effected a 31–66% reduction in black carbon particle concentrations inside three schools compared with ambient air concentrations. After improved filtration systems were installed, black carbon particle concentrations were reduced by 74–97% inside three classrooms relative to ambient air concentrations. Average black carbon particle concentrations inside the schools with improved filtration systems were lower than typical ambient Las Vegas concentrations by 49–96%. Gaseous pollutants were higher indoors than outdoors. The higher indoor concentrations most likely originated at least partially from indoor sources, which were not targeted as part of this intervention.  相似文献   
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173.
Numerical modelling of redox flow battery (RFB) systems allows the technical and commercial performance of different designs to be predicted without costly lab, pilot and full-scale testing. A numerical model of a redox flow battery was used in conjunction with a simple cost model incorporating capital and operating costs to predict the technical and commercial performance of a 120 MWh/15 MW utility-scale polysulphide-bromine (PSB) storage plant for arbitrage applications. Based on 2006 prices, the system was predicted to make a net loss of 0.45 p kWh−1 at an optimum current density of 500 A m−2 and an energy efficiency of 64%. The system was predicted to become economic for arbitrage (assuming no further costs were incurred) if the rate constants of both electrolytes could be increased to 10−5 m s−1, for example by using a suitable (low cost) electrocatalyst. The economic viability was found to be strongly sensitive to the costs of the electrochemical cells and the electrical energy price differential.  相似文献   
174.
BACKGROUND: The Institute of Medicine's 2001 report on quality delimits six dimensions of optimal care: safety, effectiveness, efficiency, timeliness, patient centeredness, and equity. In fall 2001 parents of pediatric cancer patients were interviewed to determine how well they thought these dimensions were addressed with respect to medication administration. Immediate goals were to identify system weaknesses and devise strategies to prevent future errors. A higher-order goal was to develop and demonstrate a model protocol for rapid-cycle interview assessments. METHODS: Hematology/oncology directors worked with a research expert to develop a semistructured interview protocol. After training, which included directed reading, oral instruction, and role-playing, a convenience sample of 20 English- and Spanish-speaking parents of inpatients was recruited. Parents were asked to characterize current medication administration practices and to describe problems that they had experienced or witnessed. Rapid content analysis techniques were used to identify issues of importance to the parents. FINDINGS: Parents' medication concerns centered on their children's comfort. Parents called for communication improvements, standardization of all nursing procedures and techniques, and a guide or an outline providing a clear understanding of what to expect when and from whom. Viewing these concerns in relation to the Institute of Medicine's quality domains allowed the department to frame an improvement action plan aligned with organizational and national priorities. IMPLICATIONS: With good supervision and limited focused training, inexperienced staff can successfully administer semistructured qualitative interviews and help analyze findings for rapid cycle improvement purposes. The protocol can be adapted for use in organizations interested in rapid qualitative assessments of patient and parent preferences.  相似文献   
175.
The practice fields of psychology develop through specialization in training and education. The recognized specialties play a major role in developing new opportunities for professional psychology and providing quality services for the public. The essential tension comes from the balance of innovation and tradition and, in professional psychology, from the balance of fragmentation and unification. As an example, specialization in clinical child psychology is integrated within the broad and general traditions. The greater degree of focused science and practice in a specialty is the logical consequence of advances of the discipline and profession of psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
176.
An InGaAsP multiple-quantum-well asymmetric Fabry-Pe/spl acute/rot modulator/detector has been developed for radio-over-fiber systems. The measured bandwidth is more than 6 GHz and the total insertion loss is 7.1 dB. The property of nonlinearity and spurious-free dynamic range (SFDR) has been studied theoretically. By optimizing the operation optical wavelength and bias voltage based on the numerical simulation, fifth-order nonlinearity dominates the intermodulation distortion and an SFDR of 101 dB/spl middot/Hz/sup 4/5/ has been achieved experimentally.  相似文献   
177.
Surely it must be possible to bring products to market faster and do it cheaper? These two requirements have for many years challenged the entire telecommunications industry. Complexity is a characteristic of today’s communications environments. Making this complexity manageable is the key to enabling these requirements to be met, but how? Within the intelligent network’s area it has been possible to break down the needs of the customer into a series of blocks that can be designed and deployed in flexible arrangements. To design and run these blocks two environments are used, the service assembly environment (SAE) and the service execution environment. This paper will look at the former to examine what steps need to be taken to apply these principles to the full range of communications products that a large telecommunications company like BT offer. This paper defines the SAE as including both the design phase of a product as well as its deployment into the portfolio and systems.  相似文献   
178.
Image-guided neurosurgery relies on accurate registration of the patient, the preoperative image series, and the surgical instruments in the same coordinate space. Recent clinical reports have documented the magnitude of gravity-induced brain deformation in the operating room and suggest these levels of tissue motion may compromise the integrity of such systems. We are investigating a model-based strategy which exploits the wealth of readily-available preoperative information in conjunction with intraoperatively acquired data to construct and drive a three dimensional (3-D) computational model which estimates volumetric displacements in order to update the neuronavigational image set. Using model calculations, the preoperative image database can be deformed to generate a more accurate representation of the surgical focus during an operation. In this paper, we present a preliminary study of four patients that experienced substantial brain deformation from gravity and correlate cortical shift measurements with model predictions. Additionally, we illustrate our image deforming algorithm and demonstrate that preoperative image resolution is maintained. Results over the four cases show that the brain shifted, on average, 5.7 mm in the direction of gravity and that model predictions could reduce this misregistration error to an average of 1.2 mm.  相似文献   
179.
Previous research has found differences in the speed and accuracy of responses involving concrete cognate nouns and non-cognate nouns in a range of written and "on-line" tasks using neurologically unimpaired, bilingual adults. The present study investigated whether cognateness affects verbal confrontation naming performance in balanced French/English bilinguals (N = 15 aphasic and 15 non-aphasic subjects). Subjects met selection criteria for equal proficiency, regular use, and early acquisition of both languages. Results of a picture naming test show that cognate pictures were more often correctly named in both languages than were non-cognates. Some error types and self-correction behaviors also varied with cognate status. There were similarities between the results of this study and those of previous studies of monolingual naming. Some error types and self-correction strategies appear to be unique to bilingual speakers. Theoretical questions and treatment applications arising from these findings are outlined.  相似文献   
180.
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