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91.
In this paper, we present a formulation and numerical simulation for the phase shift of light as it is passed through dynamically forced optical fibers. A generalized representation for the induced phase shift, as well as a finite element model appropriate for an isotropic, arbitrarily oriented fiber is developed. These general expressions are then specialized to the particular case of a straight, finite length of fiber, which is forced normally along its entire length. Calculations are carried out for three quite different fiber configurations over a spectrum of frequencies, and the resulting phase and strain responses are presented and discussed 相似文献
92.
M Cotellessa M Mazzella R Mulas A Caratozzolo C Romano 《Canadian Metallurgical Quarterly》1995,47(6):245-248
Three female patients with a previously poorly controlled Insulin Dependent Diabetes Mellitus (IDDM), without evidence of cardiovascular, hepatic or renal dysfunction, developed generalized edema after a substantial increase in their insulin dosage. Edema resolved in 2-3 weeks, without specific therapy. Our patient's findings met the criteria of diagnosis of insulin edema. Insulin edema during IDDM is an uncommon complication of insulin therapy (1/400) and its pathogenesis is not clarified so far; it is a transient and self-limiting condition. The diagnosis is based on exclusion of all other major causes of edema. 相似文献
93.
A Varveri L Sgorbini S Romano G Aurigemma A Dagianti R Sessa M Di Pietro M Del Piano A Dagianti M Penco 《Canadian Metallurgical Quarterly》1998,43(10):1053-1058
The aim of this study was to assess the presence of Chlamydia pneumoniae antibodies in patients with angiographically verified atherosclerotic coronary artery disease. A total of 114 consecutive patients were investigated between April 1995 and June 1996. Patients were divided into two groups: 72 patients with acute myocardial infarction (AMI; 53 men, 19 women, mean age 62.27 +/- 10.1 years), and 42 patients with chronic ischemic heart disease (CAD; 37 men, 5 women, mean age 62.75 +/- 9.2 years). A control group of 50 normal subjects matched for age (mean 62 +/- 9 years), sex, social status and geographical area was used. Identification of Chlamydia pneumoniae was carried out with the microimmunofluorescence method, on two serum samples taken from patients on admission and after 15 days. The IgM, IgG and IgA anti-Chlamydia pneumoniae titers were assessed, values > or = 1:16, > or = 1:32 and > or = 1:8 being respectively considered positive. Acute (IgM > or = 16 or four fold rise of IgG titer) and chronic (IgG > or = 128 e IgA > or = 32 or only elevated IgA titer) infections were analyzed. IgM antibodies were not found in AMI, CAD and control groups. IgG positivity (IgG > or = 32) was found in 38% of the control group, in 58.3% of the AMI group (p < 0.05) and 42.8% of the CAD group (p < 0.01). IgA positivity > or = 8) was found in 22% of the control group, in 31.9% of the AMI group (NS) and in 33.3% of the CAD group (p < or = 0.05). Acute infection was observed in 5.5% of AMI patients and in 12% of CAD patients (NS), whereas no subject of the control group showed these values. Chronic infection was observed in 9.7% of AMI patients and in 16.6% of CAD patients (NS) whereas nobody of the control group showed these values. In conclusion, our results suggest that Chlamydia pneumoniae infection is present only in the AMI and CAD groups. It is possible to suppose that this infection may be linked to atherosclerosis through an endothelial damage or a systemic endogenous procoagulant and inflammatory activity. 相似文献
94.
We study and compare three different approximation criteria for a class of problems with product objective function. We also show that a dominance rule is a necessary and sufficient condition for the approximability of the same class of problems. 相似文献
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We have considered a differential diagnosis of clinical hyperkalemia. The clinical signs and symptoms of patients with hyperkalemia are manifold and can involve many organ systems. The nonoliguric chronic renal failure patient with hyporeninemia and hypoaldosteronemia may have as one of his principal problems recurrent hyperkalemia. Treatment of this condition includes well-known modalities such as administration of calcium salts, NaHCO3, removal of potassium with resin or dialysis as well as placement of a transvenous pacemaker in anticipation of bradyarrhythmias or asystole. 相似文献
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E. Bartezzaghi C. Ciborra A. De Maio P. Maggiolini P. Romano 《Information & Management》1981,4(5):239-258
Results are presented of a pilot study dealing with the interaction between computers, management, and organization structures: a study carried out to explore the computerization phenomenon in a small sample of manufacturing firms. A short survey of the literature introduces the perspectives and objectives of the field study. Two main research outcomes are presented. Firstly, a theoretical scheme of analysis, based on the control system of administrative processes, is considered as a means of evaluating computer impact on the organization. Secondly, a set of specific hypotheses is introduced in order to analyse the empirical data.The following interactions between computers and organizational structures have been examined (while considering the firm as an open socio-technical system): technology and environment, organizational structure, automatized applications, and the computerization process. 相似文献