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A detection-theoretic analysis of the auditory localization of dual-impulse stimuli is described, and a model for the processing of spatial cues in the echo pulse is developed. Although for over 50 years "echo suppression" has been the topic of intense theoretical and empirical study within the hearing sciences, only a rudimentary understanding of its mechanisms has emerged. In this article, psychometric functions and results from matching studies are used in developing a model that specifies the perceived position of the echo pulse as a normal deviate, with an expectation that is a logistic function of the echo delay and a variance that depends on interaural time difference. Loss of information in the echo event is quantified as a decline in the efficiency with which the binaural system receives information from the lag impulse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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VS Nikiforov EV Stepaniuk IM Dunin RN Zyskunova 《Canadian Metallurgical Quarterly》1995,31(11):1582-1584
Linkage between loci controlling variants of beta-lactoglobulin and blood groups of the J system in cattle was studied by means of stochastic genetic methods reported earlier. The studies were conducted on a herd of Black Pied cattle improved with Holstein sires; population genetic data were analyzed. A plot for lod score was constructed, and point (r - 0.28) and interval estimations of the coefficient of recombination were obtained. The results are in good agreement with earlier reported data on other subjects. 相似文献
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VS Prokopchuk 《Canadian Metallurgical Quarterly》1997,(3):51-55
It has been ascertained that myofibroblasts penetrating the aortal intima from the medium layer because of its compensatory rearrangements in sites of wear and pull of the vascular wall when a fibrous plaque becomes a lipid one, get transformed in stages. Ordinarily elongated orderly arranged cells become spider-like ones, polymorphous, disintegrated cells. Lipid drops get accumulated in their cytoplasma. The above myofibroblasts were identified as Langhans' cells. Changes are reported in aortal intima plaques identical to those occurring in cell culture near the Ge?flik's [correction of Geuflick's] line. It means that accumulation of lipids in aortal plaques and atheromatous degeneration of the latter may be related to aging and necrosis of myofibroblasts which reach the Ge?flik's [correction of Geuflick's] line too soon in such sites of their compensatory proliferation as enlargements of fibrous tissue in the intima. Thus, atherosclerosis is to be regarded as quite a natural process, as reaction of re-arrangements of the vascular wall in sites of its premature wear. Prophylaxis of atherosclerosis is a problem of major social concern, which may be solved only through providing adequate conditions of work and life, cultivating a healthy life style. 相似文献
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MB Iarustovski? RG Grigor'iants VS Timokhov MV Abramian IL Mikha?lova SS Volkova IaV Banketov II Golenishchev II Iakovleva 《Canadian Metallurgical Quarterly》1997,(6):40-46
The efficacy of continuous methods of renal substitute therapy (RST) in patients with multiple organ failure is assessed. The patients were divided in 2 groups administered different types of PST. Group 1 were 16 patients subjected to RST by peritoneal dialysis, in group 2 (n = 16) GP and/or GDP were used. Hemodynamics, hematological and biochemical values, and clearance of inflammation mediators were monitored and hemohydrobalance and complications of therapy assessed in the course of RST. Both RST methods proved to be highly effective. The possibility of differentiated use of peritoneal dialysis and GP/GDP permits an individual approach to treatment, and equally high efficacy of both methods solves the problem of treating total renal insufficiency in the majority of patients with multiple organ failure following cardiovascular surgery. 相似文献
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A. N. Prokunin A. Z. Petrosyan M. L. Fridman 《Journal of Engineering Physics and Thermophysics》1986,51(4):1201-1204
The method of rapid heating of the medium was used for investigating the dependence of the viscosity of polyvinyl chloride plastisols on the temperature and time in connection with isothermal molding in casting practice.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 51, No. 4, pp. 609–613, October, 1986. 相似文献
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VS Ramachandran 《Canadian Metallurgical Quarterly》1995,4(1):22-51
Patients with right parietal lesions often deny their paralysis (anosognosia), but do they have "tacit" knowledge of their paralysis? I devised three novel tests to explore this. First, the patients were given a choice between a bimanual task (e.g., tying shoe laces) vs a unimanual one (e.g., threading a bolt). They chose the former on 17 of 18 trials and, surprisingly, showed no frustration or learning despite repeated failed attempts. I conclude that they have no tacit knowledge of paralysis (or, if such knowledge exists, it is not available for this particular task). Second, I used a "virtual reality box" to convey the optical illusion to the patient that she was moving her paralyzed left hand up and down to the rhythm of a metronome, and yet she showed no sign of surprise. Third, I irrigated patient BM's left ear canal with cold water, a procedure that is known to shift that patient's spatial frame of reference by stimulating the vestibular system. Surprisingly, this allowed her "repressed" memory of the paralysis to come to the surface; she said she had been paralyzed continuously for several days. I suggest that the vestibular stimulation produces these remarkable effects by mimicking REM sleep. These patients also employ a whole arsenal of grossly exaggerated Freudian "defense mechanisms" to account for their paralysis. To explain this, I propose that in normal individuals the left hemisphere ordinarily deals with small, local anomalies by trying to impose consistency but, when the anomaly exceeds threshold, an interaction with the right hemisphere forces a "paradigm shift." A failure of this process, in patients with right hemisphere damage, might partially account for anosognosia. Finally, I present a new conceptual framework that may help link several psychological and neurological phenomena such as Freudian defense mechanisms, vestibular stimulation, anosognosia, memory repression, visual illusions, anterograde amnesia, REM sleep, dreaming, and humor. 相似文献