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41.
Gerbils learned to approach a spatial-olfactory stimulus that signaled access to their pairmate. Experiments 1 and 3 used a discrimination procedure in which 1 conditioned stimulus (the CS+) was presented immediately before access to the pairmate and another (the CS-) was presented alone. Both male and female gerbils came to approach the CS+ sooner than the CS- and spent more time near the CS+ than the CS-. Discrimination learning was facilitated by making the CS+ and CS- spatially distinct (Experiment 3). Learning also was demonstrated in male gerbils, using a between-subjects design with a single CS. Pairing the CS with the opportunity for social interaction resulted in greater approach to the CS within 10 trials than presenting the CS and social opportunity in an unpaired fashion (Experiment 2). These findings demonstrate social-affiliative learning in the Mongolian gerbil. Similarities and differences between these findings and sexual conditioning effects in other species are discussed. 相似文献
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43.
10 pictures were viewed for 10 sec. each, during which the eye fixations were photographed and GSR was recorded. An independent assessment was made for each of 16 Ss of the defenses of isolation and repression. The defense of isolation was strikingly associated with venturing to look around more, and the defense of repression with looking around less: in contrast to repressors, isolators looked at the "ground" as well as the figure; they scattered their fixations and they made bigger jumps from 1 fixation to the next. Isolation was better than repression for the recall of sexual content. No strong trends emerged from correlations of GSR and defense ratings. Some looking measures correlated significantly with standard Rorschach scores. The findings seem consistent with results for cognitive styles as well as with clinical understanding of the defenses. (22 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Patricia A. Barton 《Journal of the science of food and agriculture》1967,18(7):298-304
Two reflectance ratios, R650/570 and R540/560 and c.i.e. colour values were compared as methods of measuring the colour stability of cooked cured meat to light and air. The limits of fading given by the pigments nitrosomyochrome and metmyochrome were determined for each method, and were followed by a series of stability tests to evaluate the suitability of each to follow the course of fading. In addition the relationships between R650/570 and R540/560 and the nitroso-pigment content and % conversion to the cured meat pigment were investigated. All the prospective methods followed the course of fading satisfactorily, but only one of them, R540/560, could be used for all the muscle and curing groups investigated. 相似文献
45.
46.
We have developed a custom analog CMOS circuit to perform the signal processing for an optical coherence tomography imaging system. The circuit is realized in a 1.5 /spl mu/m low-noise analog CMOS technology. The circuitry extracts the Doppler frequency from the signal and electrically mixes this with the original signal to provide a filtered A-scan. The circuitry was used to produce a two-dimensional image of an onion. 相似文献
47.
The design and fabrication procedures for implementing a high-density (16-microm center spacing) single-mode fiber (SMF) array are described. The specific application for this array is a parallel optical coherence tomography system for endoscopic imaging. We obtained fiber elements by etching standard single-mode SMF-28 fibers to a diameter of 14-15 microm. We equalized 1-m lengths of fiber to within 1 mm by using a fiber interferometer setup, and we describe a method for packaging arrays with as many as 100 fibers. 相似文献
48.
We have designed a multimodality system that combines optical coherence tomography (OCT) and laser-induced fluorescence (LIF) in a 2.0-mm-diameter endoscopic package. OCT provides approximately 18-microm resolution cross-sectional structural information over a 6-mm field. LIF spectra are collected sequentially at submillimeter resolution across the same field and provide histochemical information about the tissue. We present the use of a rod prism to reduce the asymmetry in the OCT beam caused by a cylindrical window. The endoscope has been applied to investigate mouse colon cancer in vivo. 相似文献
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50.
Barton IM Britten JA Dixit SN Summers LJ Thomas IM Rushford MC Lu K Hyde RA Perry MD 《Applied optics》2001,40(4):447-451
We describe the advantages of using diffractive (Fresnel) lenses on thin membranes over conventional optics for, among others, future space telescope projects. Fabrication methods are presented for lenses on two types of freestanding membrane up to 50 cm in size. The first is a Fresnel lens etched into a thin (380-mum) glass sheet, and the second is an ~50-mum-thick polymer membrane containing a Fresnel lens made by replication process from a specially made fused-silica master. We show optical performance analysis of all the lenses that are fabricated, including a diffraction-limited Airy spot from a 20-m- focal-length membrane lens in a diffractive telescope system. 相似文献