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881.
The sleep apnea/hypopnea syndrome is a very common sleep disorder, characterised by disrupted breathing during sleep. Depending on the extent of the disruptions to sleep, these are classified as apneas or hypopneas. In order to locate these apneic events an analysis of respiratory signals recorded for an entire night’s sleep is necessary. However, identifying and classifying apneic events is a complex task, given the error associated with the process for digitising signals, variability in expert criteria and the complexity of the signals themselves. This article describes a fuzzy-logic-based automated system for detecting apneic events and classifying them as apneas or hypopneas. The aim is to equip this system with mechanisms for dealing with imprecision and reasoning affected by uncertainty. The ultimate goal was to assist the physician in diagnosing the sleep apnea/hypopnea syndrome. Results in terms of locating events in the polysomnogram showed sensitivity and specificity of 0.87 and 0.89, respectively. A receiver operating curve index of 0.88 was obtained for the classification of events as apneas or hypopneas. 相似文献
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A technique for improving the uniformity of heating patterns of dielectric samples in a multimode cavity is presented based on a strategic movement of the sample inside the microwave applicator. Different optimization algorithms are compared to determine the best microwave irradiation period for each sample position. A new optimization procedure that minimizes electric field variance is also presented and assessed. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007. 相似文献
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Interferon treatment of chronic hepatitis C in human immunodeficiency virus infected patients] 总被引:1,自引:0,他引:1
C Ramos Paesa P Arazo Garcés A Pascual Catalán I Hermida Lazcano JM Aguirre Errasti 《Canadian Metallurgical Quarterly》1998,198(4):221-225
There are no reports to date of entire gene sequences coding for chitinolytic enzymes from entomopathogenic fungi, even though these enzymes act synergistically with proteolytic enzymes to solubilize insect cuticle during the key step of host penetration, having considerable importance in the biological control of some insect pests. This paper reports the complete nucleotide sequence and analysis of the chromosomal and full-length cDNA copies of the regulated gene (chit1) coding one of the chitinases produced by the biocontrol agent Metarhizium anisopliae. Degenerated primers, encompassing conserved regions of other fungal chitinases, were used to amplify a 650-bp DNA fragment, which was used to isolate genomic and cDNA clones from M. anisopliae. Albeit at least two different chitinases are characterized in this fungus, only one chit gene was isolated. The chit1 gene is interrupted by three short typical fungal introns and has a 1,521-bp ORF, which encodes a protein of 423 amino acids with a stretch of 35 amino acid residues displaying characteristics of signal peptide. The deduced sequence of the mature protein predicts a 42-kDa protein with pI of 5.8. Southern analysis of genomic DNA indicates a single copy of chit1 in the M. anisopliae genome. 相似文献
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A Pascual-Leone JM Tormos J Keenan F Tarazona C Ca?ete MD Catalá 《Canadian Metallurgical Quarterly》1998,15(4):333-343
Transcranial magnetic stimulation (TMS) can be applied in different paradigms to obtain a measure of various aspects of cortical excitability. These different TMS paradigms provide information about different neurotransmitter systems, enhance our understanding about the pathophysiology of neuropsychiatric conditions, and in the future may be helpful as a guide for pharmacological interventions. In addition, repetitive TMS (rTMS) modulates cortical excitability beyond the duration of the rTMS trains themselves. Depending on rTMS parameters, a lasting inhibition or facilitation of cortical excitability can be induced. These effects can be demonstrated neurophysiologically or by combining rTMS with neuroimaging techniques. The effects do not remain limited to the cortical area directly targeted by rTMS, but affect a wider neural network transynaptically. Modulation of cortical excitability by rTMS may in the future be useful not only as a research tool but also as a therapeutic intervention in neurology, psychiatry, and neurorehabilitation. 相似文献
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In the last years, the employment of RANS codes for a wide range of naval architecture problems is grown, since this methodology is capable of reproducing physical behaviors that are generally neglected by other models. The paper presents the results of a set of numerical tests performed employing this methodology with the aim of verifying its capability in the solution of seakeeping problem. Several condition are analyzed varying the frequency of the incident wave and its amplitude, in order to catch nonlinear effects. The results are compared with the ones achieved by a weakly nonlinear procedure based on potential theory.
相似文献890.