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31.
Fadwa T. Eljack Ahmed F. Abdelhady Mario R. Eden Frederico B. Gabriel Xiaoyun Qin Mahmoud M. El-Halwagi 《Computers & Chemical Engineering》2005,29(11-12):2304
Decoupling the constitutive equations from the balance and constraint equations allows for reformulating a conventional forward problem into two reverse problems. The first reverse problem is the reverse of a simulation problem, where the process model is solved in terms of the constitutive (synthesis/design) variables instead of the process variables, thus providing the synthesis/design targets. The second reverse problem (reverse property prediction) solves the constitutive equations to identify unit operations, operating conditions and/or products by matching the synthesis/design targets. Visualization of the problem is achieved by employing recently developed property clustering techniques, which allows a high-dimensional problem to be visualized in two or three dimensions. The clusters by definition satisfy intra-stream and inter-stream conservation through linear “mixing” rules, which allows for the development of consistent additive rules along with their ternary representation. 相似文献
32.
C Vayssettes-Courchay AA Cordi JM Lacoste M Laubie TJ Verbeuren 《Canadian Metallurgical Quarterly》1997,122(7):1361-1366
BACKGROUND AND PURPOSE: Studies on risk factors for stroke have been less intensive than those for coronary disease. Only a few studies have addressed the question of the role of heredity in the occurrence of stroke. We analyzed whether a positive parental history of cardiovascular disease predicts the risk of stroke independently from other risk factors and whether the role of parental history varies by age and stroke subtypes. METHODS: This study was a prospective follow-up of 14371 middle-aged men and women. A positive parental history of cardiovascular disease was defined as either stroke or coronary disease before the age of 60 years. The end point of the follow-up was an incident case of stroke. Multivariate analyses were performed with the Cox proportional hazards model. RESULTS: The risk ratio of stroke after multifactorial adjustment (age, smoking, blood pressure, cholesterol, diabetes, and education) associated with a positive parental history of stroke was 1.89 (P = .004) in men and 1.80 (P = .007) in women. The association between parental history of stroke and the risk of stroke was stronger among subjects aged 25 to 49 years than among older subjects. Parental history of coronary disease was not associated with the risk of stroke in men, but in women it had a borderline significant association with the risk of ischemic stroke. CONCLUSIONS: A positive parental history of stroke predicted the risk of stroke independently from the other risk factors. 相似文献
33.
34.
OM Takayanagui AA Castro e Silva RC Santiago NS Odashima VC Terra AM Takayanagui 《Canadian Metallurgical Quarterly》1996,54(4):557-564
Cysticercosis is a severe public health problem in several regions of Asia, Africa and Latin America. Epidemiologic studies based on the frequency of cases observed in specialized neurology, neurosurgery and computed tomography services, at autopsy and in seroepidemiologic studies do not permit the determination of the true prevalence of the disease in the population. The objective of the present study was to investigate the prevalence of cysticercosis by compulsory notification. The coefficient of prevalence was 54 cases/100,000 inhabitants in the municipality of Ribeir?o Preto. The results also indicated that cysticercosis is not under control in our region since 21% of cases presented the active form of the disease. Compulsory notification proved to be a valuable resource for the epidemiologic study of cysticercosis, also permitting the mapping of more affected areas for a better direction of prevention strategies. 相似文献
35.
This report analyzes the intracorporal lengths of 236 consecutive organically impotent men who underwent insertion of a penile prosthesis. The average right or left intracorporal length in this series was 20.9 cm, with a standard deviation of 2.2 cm. Intracorporal length ranged from 14-27 cm. This data may be used as reference ranges for penile prosthesis manufacturers, and for Urologists who implant prostheses or perform penile lengthening procedures. 相似文献
36.
37.
Two cases of female patients operated fo the tumors of the stomach are presented. Result of histologic examination was rather surprising in both cases--leiomyoma. 相似文献
38.
Calcified and fibrotic coronary artery lesions cannot always be dilated with conventional balloon angioplasty even at high pressures. This study examines the success of excimer laser facilitated angioplasty in 38 lesions in 37 patients with lesions that failed balloon angioplasty alone. 相似文献
39.
Adrian Thomas Christopher D. Gilson Tanveer Ahmed 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,64(1):73-79
Equipment was developed to measure the time for complete gelling of sodium alginate fibres in calcium chloride solution, taken as the time to achieve maximum tensile strength. The effects of fibre diameter, alginate concentration, alginate composition and calcium chloride concentration on gelling time were investigated. A diffusional model, developed to predict the gelling time, agreed with experimental results except for the effect of calcium ion concentration which was modelled empirically. 相似文献
40.
Livedo racemosa with cerebrovascular lesions has been described as Ehrmann-Sneddon syndrome. The etiopathogenetic factors provoking the vascular lesions, however, are of high diversity reaching from mechanical to autoimmune causes. We present a male patient with typical livedo racemosa, muscle pain and feeling of coldness of the forearms. By dermatohistopathology and magnetic resonance tomography of the brain, Ehrmann-Sneddon syndrome could be confirmed. At this time a chronic streptococcal infection could be diagnosed. Antibiotics, anticoagulants and vascularity-supplying therapy improved the clinical and subjective symptoms. Six months later, the patient developed dizziness, vision disorder, hypesthesia of the right forehead, malaise and weight loss. A further diagnostic workup including echocardiography revealed a myxoma of the left atrium. This report illustrates the association of Ehrmann-Sneddon syndrome with cardiac myxoma and points out that cardiac diagnostic examination should be included when dealing with small-vessel involvement of the brain. 相似文献