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31.
This paper studies the non-blocking conditions of a generic N × N multistage interconnection network, such as an omega network or an n-cube network, in which only one path connects any inlet to each outlet and different I/O paths can share interstage links. It is widely known that any of these networks is non-blocking for a compact and monotone pattern of k ≤ N I/O paths. Recently it has become very important to show the network non-blocking property for permutation sets, wider than the compact and monotone, which are usually encountered in broadband ATM networks. By using a new approach based on the concept of distance between I/O paths, we show here that these networks are non-blocking for a set of I/O paths obtained by shifting cyclically the inlets of a compact and monotone pattern of I/O paths by an arbitrary number of steps. 相似文献
32.
The objective of this work was to study the relationship between daily sleep time and characteristics of students, e.g. grade level, gender, and academic program. A sleep habit questionnaire was designed to survey students at two junior high schools, one from northern Taipei and the other from southern Taipei. The impact of shortened duration of sleep on daily function was also evaluated. A total of 965 students and their parents were selected randomly in December 1993 for the questionnaire study. The response rate was 96.4% (930) for students and 88.6% (855) for parents. The self-reported daily sleep time of students declined, and daytime sleepiness and moodiness increased in the higher grades. The girls slept fewer hours than the boys and did not show an increase in daytime sleepiness. Those students not taking the senior high school joint entrance examination slept more hours at night and maintained more alertness in the daytime than those who were taking the examination. The more academic pressures that adolescents faced, the fewer hours they slept. Students not participating in the joint entrance examination seemed to show a healthier sleep pattern. Little sleep at night made the students feel sleepy in the daytime and tired, drowsy, moody and difficult at arising in the morning. The reason why girls slept less than boys needs further investigation. 相似文献
33.
The complete mechanism by which pathogenic mtDNA mutations cause cellular pathophysiology and in some cases cell death is unclear. Oxidant stress is especially toxic to excitable nerve and muscle cells, cells that are often affected in mitochondrial disease. The sensitivity of cells bearing the LHON, MELAS, and MERRF mutations to oxidant stress was determined. All were significantly more sensitive to H2O2 exposure than their nonmutant cybrid controls, the order of sensitivity was MELAS > LHON > MERRF > controls. Depletion of Ca2+ from the medium protected all cell lines from oxidant stress, consistent with the hypothesis that death induced by oxidant stress is Ca(2+)-dependent. A potential downstream target of Ca2+ is the mitochondrial permeability transition, MPT, which is inhibited by cyclosporin A. Treatment of MELAS, LHON, and MERRF cells with cyclosporin A caused significant rescue from oxidant exposure, and in each case significantly greater rescue of mutant than control cells. The pronounced oxidant-sensitivity of mutant cells, and their protection by Ca2+ depletion and CsA, has potential implications for both the pathophysiological mechanism and therapy of these mitochondrial genetic diseases. 相似文献
34.
Fifteen paediatric patients with Salmonella meningitis were retrospectively reviewed. Presenting symptoms and signs included fever, vomiting, seizures, poor activity, diarrhoea and bulging anterior fontanelle in most patients. Seven out of eight patients with prolonged fever for > 10 days had neurologic sequelae; therefore, prolonged fever is a significant prognostic factor of a poor outcome (p < 0.005). All 15 patients had a brain ultrasound or computed tomography in the acute stage and 11 patients had abnormal findings. The 14 surviving patients were treated with a third-generation cephalosporin for at least 3 weeks. Seven patients (47%) made complete recoveries; two of them were treated solely with a third-generation cephalosporin. Only one mortality (6%) occurred and there were no relapses. In conclusion, high frequencies of prolonged fever, neuroimaging abnormalities and neurologic sequelae were seen in patients with Salmonella meningitis treated with third-generation cephalosporins. 相似文献
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Comparison of interaction energy between an oligonucleotide and a DNA-binding ligand in the minor and major groove modes was made by use of restrained molecular dynamics. Distortion in DNA was found for the major groove mode whereas less significant changes for both ligand and DNA were detected for the minor groove binding after molecular dynamics simulation. The conformation of the ligand obtained from the major groove modes resembles that computed with the ligand soaked in water. The van der Waals contact energy was found to be as significant as electrostatic energy and more important for difference in binding energy between these two binding modes. The importance of van der Waals force in groove binding was supported by computations on the complex formed by the repressor peptide fragment from the bacteriophage 434 and its operator oligonucleotide. 相似文献
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A fiber-optic vibration sensor based on polarization and phase-step interferometry is reported. Left- and right-circularly polarized light coming back from the reference and signal arms of a modified Michelson fiber interferometer is processed with an array of five linear analyzers separated angular steps of π/4 (rad) from each other. Thus, five interference patterns are acquired simultaneously and the dynamical phase retrieval problem is reduced to five-step interferometry in the time-domain. A vibration sensor as described above was built by the authors and its performance was investigated 相似文献
40.
The pharmacology, pharmacokinetics, clinical efficacy, adverse effects, and dosage and administration of torsemide are reviewed. Torsemide belongs to the pyridine-sulfonylurea class of loop diuretics. Its primary site of activity is the thick ascending limb of the loop of Henle, where it blocks active reabsorption of sodium and chloride, resulting in diuresis, natriuresis, and other effects. Torsemide has high bioavailability, a relatively long half-life, and a prolonged duration of activity. It is highly protein bound. Clinical trials indicate that torsemide is effective in the treatment of hypertension and of edema and other symptoms in patients with chronic renal failure (CRF), hepatic dysfunction, or congestive heart failure (CHF). Torsemide has infrequent, mild, and transient adverse effects; among the most common are orthostatic hypotension, fatigue, dizziness, and nervousness. The recommended initial oral dosages of torsemide are 10-20 mg/day for CHF, 20 mg/day for CRF, 5 mg/day for hypertension, and 5-10 mg/day (in combination with a potassium-sparing diuretic or aldosterone antagonist) for hepatic cirrhosis. In most patients, the pharmacokinetic advantages of torsemide over other loop diuretics are unlikely to translate into a substantial edge in clinical outcomes, and in practice there may be no cost advantages. Although torsemide does not offer major advantages over other loop diuretics, it may be of benefit in patients who do not respond to or cannot tolerate other agents. 相似文献