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Metallurgical and Materials Transactions A - We developed an Fe–22Mn–0.6C–1.5Al TWIP steel and investigated how thermo-mechanical processes affect the mechanical properties. In...  相似文献   
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Das SK  Rey AD 《Nanotechnology》2005,16(7):S330-S337
Simulations of material architectures in polymer-liquid crystal blends driven by phase separation-phase ordering-texturing processes are presented. The study shows that mixtures of polymers and liquid crystals result in blend morphologies that organize at several scales. For thermally driven instabilities, morphologies of polymer droplets embedded in a liquid crystal matrix show colloidal crystallinity. Large polymer drops strongly affect the orientation of the matrix, producing textures consisting of defect lattices. This work shows that thermally driven phase separation-phase ordering-texturing processes can result in multiscale materials, with length scales cascading down from droplets to interfaces, and finally to nanoscale defects.  相似文献   
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In this report, the authors explore the relationships of perceived treatment to outcome in a large, placebo-controlled trial of nicotine replacement treatment for smoking reduction. In the original study (J. F. Etter, E. Laszlo, J. P. Zellweger, C. Perrot, & T. V. Perneger, 2002), which was conducted in French-speaking Switzerland, smokers were randomly assigned to receive nicotine, matching placebo products, or no intervention. At the end of the 6-month study, participants were asked to guess whether they had received nicotine or placebo. In the present analysis, the authors examined the difference in smoking reduction between those who believed they had received nicotine and those who believed they had received placebo. Regardless of actual treatment, smokers who believed they had received nicotine had significantly better outcome than those who believed they had received placebo. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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An automated method for detecting fetal breathing and an analytic technique for providing significant data reduction that take the episodic nature of fetal breathing activity into account are described. The aim of the new technique, called epoch analysis, is to derive parameters of breathing and apnea that both summarize the activity and permit examination of its relationship to changes that occur naturally during day and night and with fetal maturation. The discussion covers: the acquisition of data from pregnant baboons; the breath detection process, for which a program was written; the recognition of breathing; computer recognition of artifacts; epoch characterization; validation of the methods of breath detection and epoch characterization; and application of the method. It is found that the technique has a broad capacity for data reduction and provides summaries of the activity that are amenable to analysis with standard statistical techniques.  相似文献   
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OBJECTIVE: To document the incidence, source, and reasons for all complaints received by a large municipal emergency medical services (EMS) program. METHODS: A retrospective review of all complaints received during three consecutive years (1990-1992) in a centralized EMS system serving a large municipality (population 2 million). All cases were categorized by year, source, and nature of the complaint. RESULTS: In the three study years, EMS responded to 416,892 incidents with nearly a half-million patient contacts. Concurrently, 371 complaints were received (incidence of 1.12 per thousand); 132 in 1990, 129 in 1991, and 110 in 1992. Most complaints involved either: 1) allegations of "rude or unprofessional conduct" (34%), 2) "didn't take patient to the hospital" (19%), or 3) "problems with medical treatment" (13%). Only 1.6% (n = 6) were response-time complaints. Other complaints included "lost/damaged property," "taken to the wrong hospital," "inappropriate billing," and "poor driving habits." The most common sources were patient's families (39%) and the patients themselves (30%). Only 7.8% were from health care providers. CONCLUSION: Reviews of complaints provide information regarding EMS system performance and reveal targets for quality improvement. For the EMS system examined, this study suggests a future training focus on interpersonal skills and heightened sensitivities, not only toward patients, but also toward bystanders and family members.  相似文献   
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OBJECTIVES: Identify factors predicting favorable outcome after medical management of valve ring abscesses in order to propose a surveillance schedule for conservative treatment. METHODS: A multicentric study conducted from July 1989 to February 1996 included 28 patients (mean age 64 +/- 16 years, range 26-83) hospitalized for active endocarditis and valve ring abscesses diagnosed at transthoracic or transesophageal echography. Conservative medical therapy was given because of a decision of the medico-surgical team (n = 9), high surgical risk (n = 12), or patient refusal of surgery (n = 7). Outcome was favourable in 18 patients (Group I) and unfavorable in 10 (Group II) due to death (n = 9) or subsequent surgery (n = 1). Univariate and multivariate analysis were used to determine differences between the groups in terms of clinical and laboratory data. RESULTS: Mean follow-up in Group I was 33 +/- 18 months and 15 +/- 10 months in Group II. Univariate analysis showed significant differences between Group I and II respectively for age (59 +/- 18 yr vs 72 +/- 10, p = 0.04), delay to apyrexia after antibiotics (4.3 +/- 2.8 vs 8.3 +/- 2.4 days, p < 0.0008), heart failure (5% vs 70%, p = 0.003), grade III or IV valvular regurgitation (5% vs 60%, p < 0.04), and mean surface area of the abscess (1.5 +/- 1.2 vs 5.4 +/- 6.4 cm2, p < 0.03). Independent factors at multivariate analysis were by decreasing order: lack of heart failure at admission, delay to apyrexia, abscess surface area, and age. Outcome was favorable (mean follow-up 33 +/- 10 months) in all patients with an abscess surface area < 1.5 cm2, no signs of heart failure, no grade III or IV valvular regurgitation, apyrexia after less than 8 days on antibiotics and no staphylococcus positive blood culture. CONCLUSION: Medical management of valve ring abscesses may be indicated in selected patients in care units with rigorous surveillance facilities. Further studies are needed to precisely identify surveillance and treatment criteria.  相似文献   
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