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181.
182.
The authors examined the influence of accreditation on educational change and reform in U.S. medical schools in the past decade, by reviewing the survey databases and site visit reports of 90 schools that had comprehensive accreditation surveys by the Liaison Committee on Medical Education (LCME) between July 1992 and June 1997. In this study, substantive change was defined as centralizing the design and management of the curriculum, as well as one or more of the following reforms: integrating basic and clinical science instruction and/or conversion to interdisciplinary courses; implementing methods of active, small-group, independent, and hypothesis-based learning; and substantially increasing students' exposure to ambulatory and primary care. Accreditation reports were reviewed to determine the extent to which the LCME previously had admonished schools for shortcomings in their educational programs and advised curricular changes. Notice was taken of grant support by national foundations promoting educational reform, in relation both to the correction of accreditation deficiencies and to curricular reform undertaken by schools on their own initiative. The study also scrutinized the evolution of accreditation standards promoting educational reform, and the LCME's support of initiatives for shortening the period of medical education and promoting performance-based teaching and the assessment of clinical skills. On entering the 1990s, the LCME toughened the standards for design and management of the medical curriculum and for the evaluation of educational program effectiveness that schools must conduct. The greater assessment rigor identified educational shortcomings in 61 of 90 medical schools coming up for accreditation surveys during 1992-1997. On those occasions, 34 of the 61 schools had instituted reforms or were on the verge of doing so. Twenty-five of the schools carrying out reforms (73%) had received major foundation grants, compared with ten of the 27 schools (37%) that had accomplished little. Fifteen schools that had not been reproached earlier were found on the 1992-1997 surveys to have undertaken substantial innovation on their own initiative, five with the help of major foundation awards. The study also shows that a number of schools implemented parts of more sweeping reforms with the help of smaller foundation grants for more discrete purposes. In some instances, it has not been possible to differentiate the influence of the LCME as a force for educational reform from the incentives for change created by national foundations. Overall, the LCME, through its standards and assessment practices, and in synergy with schools and kindred agencies promoting change, is now on the leading edge of improved education and evaluation in the nation's medical schools.  相似文献   
183.
This paper describes the facile synthesis of nanoparticle-cored dendrimers (NCDs) and nanoparticle megamers from monolayer-protected gold clusters using either single or multi-step reactions. First, 11-mercaptoundecanoic acid/hexanethiolate-protected gold clusters were synthesized using the Schiffrin reaction followed by the ligand place-exchange reaction. A convergent approach for the synthesis of nanoparticle-cored dendrimers uses a single step reaction that is an ester coupling reaction of hydroxy-functionalized dendrons with carboxylic acid-functionalized gold clusters. A divergent approach, which is based on multi-step reactions, employs the repetition of an amide coupling reaction and a Michael addition reaction to build polyamidoamine dendritic architectures around a nanoparticle core. Nanoparticle megamers, which are large dendrimer-induced nanoparticle aggregates with an average diameter of more than 300 nm, were prepared by the amide coupling reaction between polyamiodoamine [G-2] dendrimers and carboxylic acid-functionalized gold clusters. 1H NMR spectroscopy, FT-IR spectroscopy, thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) were used for the characterization of these hybrid nanoparticles.  相似文献   
184.
185.
An application of a classical design approach to an experiment involving the study of supersonic combustion is described in this paper. The case study described is that of an experiment whose objective is to create response surfaces of the mean and variance of several flow parameters as a function of location within a supersonic jet flow field. The approach demonstrated in this paper involves the use of a classic response surface methodology design in a unique manner. Additionally a unique application involving the sub‐sampling and replication strategies is developed in a similar manner to those of robust parameter design. The sub‐sampling and replication techniques allow for the ability to systematically account for the precision in mean and variance models of the output response variables. The final design prescribed met the experimental objectives of the project by creating the ability to fit response surfaces and allowing for the experimenters to understand the relative precision of their estimates based on the final sub‐sampling and replication techniques. Results from one section of the region of interest are used to illustrate two different modeling approaches. The performance of both modeling approaches in prediction of new data is illustrated. The conclusions also include a discussion of the future work that will follow. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
186.
The densification of silicon carbide (SiC) was studied using a variety of additives (Al, AlN, Al2O3, B4C, C, Si3N4, and Y2O3). The onset of densification of SiC with small amounts of additives occurred at temperatures between 1500° and 1900°C with 28 MPa applied pressure. Al, B4C, and C promoted densification, while N (added as AlN or Si3N4) retarded sintering. A 96.75 wt% SiC–2 wt% Al–1 wt% C–0.25 wt% B4C starting composition yielded the same percent of theoretical density (in the range of 70%–90% theoretical density) 400°C lower than a 95 wt% SiC–5 wt% AlN material. Yttria additions promoted intergranular fracture, which increased the single-edged precracked beam fracture toughness. The appropriate selection and amount of additives allowed for the tailoring of grain size and intergranular fracture, thus controlling the mechanical properties. While oxygen was present in all materials containing aluminum, the incorporation of additional oxygen as alumina resulted in reduced sintering activity compared with Al metal. Corrosion resistance decreased in both HF and NaOH solutions at 80°C for materials containing a grain boundary phase.  相似文献   
187.
Criminal defendants should be protected from suggestive lineup procedures by the presence of their attorneys at lineups. This protection is effective only if attorneys are sensitive to factors that affect lineup suggestiveness. This study assessed attorney sensitivity to foil, instruction, and presentation biases. Stimuli were 8 videotaped lineups in which the 3 factors were manipulated between subjects. Assistant public defenders (N?=?109) viewed the videotapes and completed a questionnaire that assessed perceptions of suggestiveness, fairness, and correctability. Attorneys were very sensitive to foil bias but only somewhat sensitive to instruction bias. Their perceptions of presentation bias were contrary to empirical research results. Attorneys reported that they are rarely present at lineups. These results imply that the presence-of-counsel safeguard may be less effective than it could and should be. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
188.
Few disagree that health care is improved by effective interdisciplinary teamwork. Most nurses are anxious to collaborate with members of other disciplines in the delivery of cost-effective care. Unfortunately, some overly zealous and mistaken proponents of the interdisciplinary approach argue that a disciplinary focus is incongruous with interdisciplinary teamwork. Nurses must resist this notion, work to strengthen the discipline, and gain the tools needed to be visible and accountable. Nursing has an important role in interdisciplinary care, and interdisciplinary teams depend on nurses' contributions to be effective and accountable.  相似文献   
189.
A single-dose study was conducted to determine concentrations of trovafloxacin (CP-99,219) achieved in the cerebrospinal fluid (CSF) relative to those in the serum of healthy subjects after intravenous infusion of alatrofloxacin (CP-116,517), the alanyl-alanyl prodrug of trovafloxacin. Twelve healthy subjects were administered single doses of alatrofloxacin at a trovafloxacin equivalent of 300 mg as an intravenous infusion over 1.0 h. CSF samples were taken by lumbar puncture at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 24 h after the start of the infusion; each subject was sampled at only one time point. Serum samples were taken from each subject at the time of CSF collection. A mean concentration of 5.8 microg of trovafloxacin per ml was present in serum 1.0 h after the start of the infusion. CSF/serum ratios ranged from 0.14 to 0.33 in the postdistribution phase (5 to 24 h postinfusion), with a mean ratio of 0.25. The most common adverse events were dizziness, nausea, and rash and were mild or moderate in intensity. The potency of trovafloxacin against susceptible organisms, coupled with its rapid penetration of CSF following the intravenous administration of alatrofloxacin, suggests that it may be useful in the treatment of bacterial meningitis in humans.  相似文献   
190.
A technique to evaluate the magnetic properties of disc and tape oxide dispersions utilizing a vibrating sample magnetometer has been developed. The method permits an assessment of dispersion quality prior to disc or tape coating and can be utilized to optimize oxide formulations as well as for quality control.  相似文献   
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