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31.
50-kHz ultrasonic vocalizations emitted by male rats during a 5-min period before introduction of a female (precontact vocalizations [PVs]) were analyzed in the context of acquisition of sexual experience. Changes in the main copulatory parameters and their N-methyl-D-aspartate (NMDA) receptor dependence, the role of contact with either anestrous or estrous females, and conditioning to odor and background cues were also investigated. Mount latency (ML) and intromission latency (IL) decreased after the 1st copulatory session, but ejaculation latency (EL) changed significantly only starting from the 4th session onward. The number of PVs gradually increased during the first 3–4 sessions. Blocking of NMDA receptors affected PVs and EL but not ML or IL. After a 5-month break in copulatory sessions, ML remained unchanged, whereas EL increased and the number of PVs decreased significantly. PVs were most robustly elevated by contact with estrous females. Exposure to background cues resulted in a linear decrease in number of PVs during 10 subsequent sessions without exposure to a female. The results suggest that, in the course of acquisition of a sexual experience, PVs reflect a learning process that depends on a rewarding value of sociosexual contact. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Halina Czternastek 《Vacuum》2008,82(10):994-997
Al-doped ZnO films were prepared by the dc magnetron sputtering technique on Suprasil-1 substrates at a temperature of 470 K. Plasma-emission monitoring was used to stabilize oxygen flow to the deposition chamber. The effect of substrate position during deposition on the structural, electrical and optical properties of the films was investigated. It was found that preparation of low-resistance films with high optical transmission over the visible region is possible under condition of low plasma effects on the growing film. 相似文献
33.
We present an extended zero-sequence equivalent circuit for compensated medium-voltage systems, with load current contribution accounted for in the zero-sequence voltage drop accounts. It opens its application to complete and eventually filtered waveforms, rather than only one frequency component. Consequently, the new zero-sequence circuit adapts more to fault-location tasks both in overhead and in cable systems, particularly in the presence of important capacitive currents, where extraction of the main charging current may be not an obvious operation. We have applied it in curve-fitting procedures for the evaluation of a single-line-to-ground fault distance. Fault resistance, fault position, and inception angle are fitting parameters. Then, the fault position is given with several percent average error, within a 10% untuning range, at small and large inception angles, and for a fault resistance up to 3 kOmega to be compared to the 50-Omega limit achieved before. 相似文献
34.
Low splice loss between 34 /spl mu/m core diameter Bragg fibre and G-652 fibre by using micro-optics
The splice loss at 1.55 /spl mu/m between a 34 /spl mu/m core diameter singlemode photonic bandgap fibre and a G-652 fibre has been dramatically reduced from 2.5 to 0.8 dB by using a micro-optics composed of graded-index and coreless pure silica fibres. 相似文献
35.
36.
Electropolishing and passivation of NiTi shape memory alloy 总被引:2,自引:0,他引:2
Electropolishing of NiTi alloy has been investigated. The influence of polishing bath composition and the operating conditions instead of the conditions of the process on the quality of the surface, evaluated by AFM and SEM methods, was established. Morphologically uniform surfaces were obtained only in the case of solutions containing hydrofluoric and sulfuric acids. Electropolished samples were sterilized and thermally passivated, then their corrosion resistance was measured in Tyrode's physiological solution. It was established that already after the electropolishing the corrosion resistance of NiTi alloy increases due to the spontaneously formed TiO2 layer. The increase of the thickness of the layer during sterilization and thermal passivation causes further increase in the corrosion resistance. 相似文献
37.
Agnieszka?NowakEmail author Danuta?Kusewicz Halina?Kalinowska Marianna?Turkiewicz Piotr?Patelski 《European Food Research and Technology》2004,219(1):84-89
Correlation between H2S productivity (p) and sulfite reductase activity (A) was estimated for seven wine-producing yeasts. It was described by a linear function
p=f(A), the slope of which depended on the yeast strain. The most intensive H2S synthesis by all the examined yeasts was observed within the early logarithmic growth phase, either in nitrogen abundance and SO2 presence, or in nitrogen deficient and SO2-free medium. Sulfite reductase from all the strains was optimally active at pH close to 7.4. The enzyme from cryophilic yeasts displayed maximum activity at approximately 16 °C, and from mesophiles at 22–26 °C. The preparations showed different affinities toward sulfite (Km of 16.7–67.5 M). Values of activation energy in sulfite reduction depended on the yeast, and ranged from 14.07 to 67.04 kJ mol–1. 相似文献
38.
The solution comprises of two parts. First, for a given groove's basal angle, liquid-solid contact angle, and the Bond number,
the shape of free surface is determined starting from the Young-Laplace equation. The optimization technique as developed
formerly is applied. Then, having determined the shape of the free surface and slope of the groove, the distribution of fluid
flow is determined. The boundary value problem is solved using boundary collocation method in least square sense. Given the
distribution of fluid velocity the friction factor as a function of the other parameters of the model is analyzed.
Received 25 November 1998 相似文献
39.
The effect of different cooking times on the GLS content in white cabbage (Brassica oleracea L. var. capitata f. alba) was determined. Cooking of cabbage for 5-30 min caused a gradual decrease in the GLS content. The most efficient reduction of the GLS content (by about 35%) occurred during the first minutes of cooking. As the cooking time was extended by another 5 min, each time the GLS content decreased by 10-15%. Higher losses in indole GLS, as compared to those of aliphatic ones, resulted from more efficient diffusion of those compounds to cooking water. The GLS content in cooking water, irrespective of the cooking time of white cabbage, remained rather stable, whereas the content of indole GLS was between 3.5- and 4-fold higher in comparison to that of aliphatic GLS. Taking into consideration the rate of changes in the content of particular GLS in cabbage and the GLS content in cooking water, it can be stated that glucoiberin was more thermolabile than other GLS. 相似文献
40.
Kaczmarek Z. Kaczmarek C. Nichoga V. 《IEEE transactions on instrumentation and measurement》2002,51(1):102-106
The correction of the effect of dispersion on the accuracy of processing in the Hopkinson bar type mechanical transducer enables extension of its application in measurements of impulsive force and pressure of short duration onto the dispersive operating range. In the experimental methods of correction, two-point measurement of the strain inside the bar is usually applied. This way, the dispersive characteristic of the bar is determined and also the process of reconstructing waveforms is performed. In the paper, a sensor of impulsive force and pressure with one-point measurement of the strain inside the bar is presented, in which the incident wave and the first reflected one, generated by the input function, are utilized. Temporal restrictions of the input function and spatial restrictions of mounting strain gauges on the bar, preventing the superposition of the incident and the first reflected pulses in the strain gauges, are given. The nonsuperposition of these pulses is the condition of the sensor functioning correctly. The method of using the sensor for reconstruction of impulsive mechanical quantities, based on the frequency-domain deconvolution, is demonstrated. The advantage of the described sensor is the reduction in the complexity of the amplification circuit and the output signal processing circuit and thus an easier achievement of the required processing accuracy 相似文献