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101.
102.
Cognitive performance in conversion hysteria 总被引:1,自引:0,他引:1
In order to test some neurobiologically based assumptions pertaining to attention and memory dysfunction in conversion hysteria, a series of tasks was given to 17 hospitalized patients with hysterical conversion reaction and to a control group of nonpsychotic patients under conditions of nonstress and stress. The results indicated significant differences in performance between hysteria and control subjects. The former group, in comparison to controls, had heightened suggestibility, greater field dependency, and greater impairment of recent memory and vigilance-attention. A discriminant analysis indicated the feasibility of using such tests as objective diagnostic criteria for hysteria. 相似文献
103.
The rapid mixing of reagents is a crucial step for on-chip chemical and biological analysis. It has been recently suggested that microfluidic mixing can be greatly enhanced by simply using time pulsing of the incoming flow rates of the two fluids to be mixed (Glasgow, I.; Aubry, N. Lab Chip 2003, 3, 114-120). This paper elaborates on the latter technique, showing through computational fluid dynamics how the mixing efficiency strongly depends on certain dimensionless parameters of the system, while remaining nearly insensitive to others. In particular, it is demonstrated that higher Strouhal numbers (ratio of flow characteristic time scale to the pulsing time period) and pulse volume ratios (ratio of the volume of fluid pulsed to the volume of inlet/outlet intersection) lead to better mixing. This paper also presents a physical device capable of mixing two reagents using pulsing, which shows improved mixing with greater values of the Strouhal number. 相似文献
104.
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106.
F.R.Ludwig Schoening 《Fuel》1982,61(8):695-699
It has been shown that the interatomic distance of ≈0.43 nm in coal is predominantly due to turbostratic-graphitic order. The height of the corresponding peak in the G(r) function which is the Fourier transform of the properly corrected and normalized X-ray diffractogram, has been investigated as a function of the concentration of volatile matter and the heat treatment of the coal. The results clearly show that this new parameter which is based on the whole diffraction pattern, is a useful aid in the study of coal, in particular when the structural changes within one coal are investigated. 相似文献
107.
Techniques for modeling and simulating channel conditions play an essential role in understanding network protocol and application behavior. In [11], we demonstrated that inaccurate modeling using a traditional analytical model yielded suboptimal error control protocol parameters choices. In this paper, we demonstrate that time-varying effects on wireless channels result in wireless traces which exhibit non-stationary behavior over small window sizes. We then present an algorithm that extracts stationary components from a collected trace in order to provide analytical channel models that, relative to traditional approaches, more accurately represent characteristics such as burstiness, statistical distribution of errors, and packet loss processes. Our algorithm also generates artificial traces with the same statistical characteristics as actual collected network traces. For validation, we develop a channel model for the circuit-switched data service in GSM and show that it: (1) more closely approximates GSM channel characteristics than traditional Markov models and (2) generates artificial traces that closely match collected traces' statistics. Using these traces in a simulator environment enables future protocol and application testing under different controlled and repeatable conditions. 相似文献
108.
The long-term variability of the fetal heart rate (FHR) provides valuable information on the fetal health status. The routine clinical FHR measurements are usually carried out by the means of ultrasound cardiography. Although the frequent FHR monitoring is recommendable, the high quality ultrasound devices are so expensive that they are not available for home care use. The passive and fully non-invasive acoustic recording called phonocardiography, provides an alternative low-cost measurement method. Unfortunately, the acoustic signal recorded on the maternal abdominal surface is heavily loaded by noise, thus the determination of the FHR raises serious signal processing issues. The development of an accurate and robust fetal phonocardiograph has been since long researched. This paper presents a novel two-channel phonocardiographic device and an advanced signal processing method for determination of the FHR. The developed system provided 83% accuracy compared to the simultaneously recorded reference ultrasound measurements. 相似文献
109.
Subramanya Sarma Vadlamani Joerg Eickemeyer Ludwig Schultz Bernhard Holzapfel 《Journal of Materials Science》2007,42(17):7586-7591
The development of strongly cube textured Cu based substrates is important in the cost effective production of long lengths
of high temperature superconducting cables. The present paper reports textures (deformation and recrystallisation) development
in pure Cu, Cu–Al, Cu–Mn (with a solute content of 1–3 at.%) and Cu–35 at.% Ni alloys. 相似文献
110.
Turrisi Rob; Mastroleo Nadine R.; Mallett Kimberly A.; Larimer Mary E.; Kilmer Jason R. 《Canadian Metallurgical Quarterly》2007,21(4):453
The present study used perspectives from the general literature on college alcohol consumption to examine mediational influences of peer, environmental, and parental variables on heavy drinking for student athlete and nonathlete samples. Eight hundred thirty-five freshmen who differed in organized sports involvement were compared on heavy drinking outcomes, peer norms, environmental influences, and parental communication. College athletes reported significantly more heavy drinking experiences than nonathletes. Peer norms, environmental influences, and parental communication were all significant mediators of the athlete-heavy drinking relationship. Athletes reported a higher perception of peer drinking, peer approval of drinking, higher alcohol availability, and direct drink offers, which, in turn, were related to higher rates of heavy drinking. Parental communication mediated the athlete-heavy drinking relationship differently, depending on the specific topic of conversation. Discussion surrounding the importance of incorporating a variety of interventions aimed at reducing collegiate athlete drinking on the basis of the peer, environmental, and parental influences observed in the present analyses are presented. Limitations and directions for future research are also noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献