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The requirements of the refractories used in gas producers, water gas sets, horizontal retorts, vertical retorts, and gas and coke ovens are discussed with respect to the specifications which the material must necessarily meet to prevent failure of the installations. Illustrations show various types of installations and details of certain refractory shapes employed. The temperatures encountered in various portions of the carbonizing chambers, flues, and regenerators give a fair idea as to the duty which the fire brick must meet in operation.  相似文献   
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Examined the structure of women's interests as shown by the SVIB, the Kuder Occupational Interest Survey, Holland's Vocational Preference Inventory, and the American College Testing Vocational Interest Profile. Analyses of the interrelationship of scales and of the interest patterns of women selecting various occupations support the similarity of the structure of women's interests to the structure previously found for men. It is suggested that this information be used to provide women with information about more and more diverse career options than are now commonly available. (27 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In this paper we give parallel algorithms for a number of problems defined on point sets and polygons. All our algorithms have optimalT(n) * P(n) products, whereT(n) is the time complexity andP(n) is the number of processors used, and are for the EREW PRAM or CREW PRAM models. Our algorithms provide parallel analogues to well-known phenomena from sequential computational geometry, such as the fact that problems for polygons can oftentimes be solved more efficiently than point-set problems, and that nearest-neighbor problems can be solved without explicitly constructing a Voronoi diagram.The research of R. Cole was supported in part by NSF Grants CCR-8702271, CCR-8902221, and CCR-8906949, by ONR Grant N00014-85-K-0046, and by a John Simon Guggenheim Memorial Foundation fellowship. M. T. Goodrich's research was supported by the National Science Foundation under Grant CCR-8810568 and by the National Science Foundation and DARPA under Grant CCR-8908092.  相似文献   
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In infants, sleeping metabolic rate (SMR) is used as a proxy for basal metabolic rate (BMR). BMR can be predicted from anthropometry using published equations. Our study was intended to evaluate the ability of these equations to predict measured SMR in infants aged 6 weeks to 12 months. SMR was measured in a mixed longitudinal study using the Douglas bag technique (n = 105). Measured SMR values were compared with BMR predicted from weight (BMR-1) or weight and length (BMR-2). These equations were not successful in predicting SMR in this age group. Percentage error of predicted BMR was related to infant weight (BMR-1: r = 0.26; p < 0.005; BMR-2: r = 0.18; p < 0.06). Alternative logarithmic equations were derived from this study (R = 0.84-0.87; SEE = 0.159-0.168). We conclude that the new equations, relating to contemporary infants, are more suitable but actual measurements remain preferred.  相似文献   
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BACKGROUND: There is no consensus about the best way to teach fiberoptic intubation. This study assesses the effectiveness of a training program in which novice anesthetic residents routinely were taught fiberoptic tracheal intubation of anesthetized, paralyzed, apneic patients. METHODS: Eight inexperienced anesthetic residents learned fiberoptic and conventional tracheal intubation simultaneously during their first 4 months of training. All intubations were performed using general anesthesia and muscle paralysis. Of these intubations, 223 (23%) were fiberoptic and 743 (77%) were laryngoscopic. Subsequently, their intubation skills with the two techniques were studied in a prospective, single-blind randomized trial involving 131 elective patients. Intubation times, SpO2, ETCO2, hemodynamic changes on intubation, and complications were recorded for 71 fiberoptic and 57 laryngoscopic intubations. RESULTS: There were two failures of the rigid and one failure of the fiberoptic technique due to inability to intubate within 180 s. In cases of failure, the tracheas were intubated successfully after mask ventilation by the alterative technique. No hypoxemia or hypercarbia occurred in any patient. There were no differences in hemodynamic indexes nor incidence of sore throat or hoarseness between the two groups. Mean intubation times were 56 +/- 24 s (mean +/- SD) for fiberoptic and 34 +/- 10 s (mean +/- SD) for laryngoscopic (P < 0.001). CONCLUSIONS: Novices taught fiberoptic intubation and rigid laryngoscopic intubation under similar conditions, with similar volumes of experience, learn both techniques well. The safety and effectiveness of this training regimen commend it for inclusion in any residency program.  相似文献   
139.
BACKGROUND: Registered mortality from cryptogenic fibrosing alveolitis (CFA) in England and Wales has increased substantially since the specific International Classification of Diseases code for CFA was introduced in 1979. However, since a significant proportion of deaths from CFA are misclassified as post inflammatory fibrosis (PIF), it is possible that the observed rise in CFA mortality is due to diagnostic transfer from this code. To investigate this, and to assess mortality trends in other countries, annual CFA and PIF mortality data from England and Wales, USA, Australia, Scotland, Canada, New Zealand, and Germany were analysed. METHODS: Crude annual mortality rates were calculated and rates standardised by Poisson regression to allow assessment of changes over time and comparison between countries, sexes, and age groups. The relative trends in mortality from CFA and PIF were assessed by calculating the annual ratio of CFA to PIF deaths. RESULTS: Men were more likely than women to die from both CFA and PIF in all countries. The highest standardised CFA mortality rate occurred in England and Wales, and the lowest in Germany. Since 1979 mortality from CFA has increased in England and Wales, Australia, Scotland and Canada, but there was no trend in CFA mortality in New Zealand or Germany. In the USA mortality from CFA was low and has fallen. Mortality from PIF increased in all countries except New Zealand and Germany, and the highest PIF mortality, together with the greatest increase over time, was seen in the USA. Changes over time in the annual ratio of CFA to PIF deaths in all countries were small, implying that diagnostic transfer is not a major cause of the increasing CFA mortality. CONCLUSIONS: Mortality from CFA continues to increase in England and Wales and in many other countries. Diagnostic transfer from PIF does not appear to be a major cause of this.  相似文献   
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