57 research outputs found
Экспериментальное исследование трибологических свойств пары терния сталь/ABS пластик с последующим поверхностным микроскопическим исследованием
Problems of civil production by high-tech enterprises
The article clearly demonstrates the need for product diversification in high-tech enterprises. The main problems associated with the development of diversification in the enterprise are stated. Shows the relationship between the release of diversified products, revenue and profit
Time course of early audiovisual interactions during speech and nonspeech central auditory processing: a magnetoencephalography study
Visual stimulation alters local 40-Hz responses in humans : an EEG-study
Irregular changing visual patterns and coherently moving bars were presented either in the upper or lower half of the visual field of 12 human subjects. EEG responses recorded over the occipital lobe showed an increase of 40 Hz spectral power when a regular pattern of moving bars appeared. This enhancement of 40-Hz activity varied as a function of visual field presentation. Coherent stimuli in the upper visual field elicited 40-Hz enhancement at lower occipital electrodes, while coherent stimulation in the lower visual field elicited 40-Hz enhancement at upper occipital electrodes. These results evidence that neuronal 40-Hz responses are a correlate of perception of coherent visual patterns in humans. Area-specific 40-Hz responses related to visual perception can be picked up in the EEG
PRES: The Controlled Noninvasive Stimulation of the Carotid Baroreceptors in Humans
To study physiological and psychological effects of baroreceptor activity, the cervical neck cuff technique has been frequently used to stimulate the carotid baroreceptors mechanically. Using this technique, no satisfying control conditions to date have been available. Because the carotid stretch receptors are sensitive not only to the pressure level, but also to the rate of change, it is possible to manipulate the receptor firing through changes in carotid pulse amplitude. The device described here relies on the application of short changes in cuff pressure tied to different phases withing the cardiac cycle (phase related external suction (PRES)). A brief external suction during systole has potent stimulatory effects on baroreceptors whereas the application of the very same pressure pulse during diastole inhibits the firing burst associated with the pulse wave. To allow an ongoing period of stimulation, a sequence of alternating negative/positive pressure pulses is applied. In the stimulation condition, the R-wave of the electrocardiogram triggers a negative pulse which is followed by a positive one during diastole. In the control condition this relationship is reversed. Two experiments are reported confirming different baroreceptor effects of the two conditions. PRES allows for blind or double-blind experiments to investigate effects of baroreceptor activity on physiology and behavior
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