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21.
E Eng M Veniant J Floege J Fingerle CE Alpers J Menard JP Clozel RJ Johnson 《Canadian Metallurgical Quarterly》1994,7(2):177-185
Previous research in this laboratory has shown that preweaning and postweaning juvenile meadow voles, Microtus pennsylvanicus, can acquire a spatial task, the Morris water-maze task. The present study examined the influence of age of juvenile acquisition ("before weaning" (BW; Day 10 and 15 after birth) and "after weaning" (AW; Day 20 and 25 after birth)) of a spatial task on subsequent re-acquisition of the same hidden-platform spatial water-maze task. This study also compared sex differences and litter sex-ratio effects on reacquisition performance. Fifteen litters of adults were re-tested in the same water maze 6 weeks after being initially tested as juveniles. All analyses were conducted using a covariate that removed the group differences in the original task performance. Adult voles from female-biased litters, that had previously learned the task at an older juvenile age (AW), reacquired the same task faster than adults that had previously learned the task at a younger juvenile age (BW). In the adult BW group there was also a significant litter sex-ratio effect such that voles born into a female-biased litter re-acquired the task more slowly than did voles born into a male-biased litter. There were no significant sex or litter sex-ratio effects on spatial learning in the AW group. These results show that adult meadow voles can require a spatial task more quickly if they initially learned the task at an older juvenile age, suggestive of a period of infantile amnesia. In addition, these results indicate that the litter sex-ratio can affect adult spatial performance, suggesting that the relative amount of androgens in utero may influence the development of sexually-dimorphic spatial ability in adulthood. 相似文献
22.
Murray R 《Architectural record》1994,182(7):30-1, 91, 99
23.
Murray R 《Architectural record》1993,181(11):48-51, 120-3
Constrained by the excesses of the previous decade and tepid performance in the general economy, the rebound by construction from its 1990-91 downturn could best be described as subdued and selective. Single-family housing led the way before faltering this year, and only scattered help has come from the industry's other sectors. The big question facing construction at the end of 1993 is whether the current recovery is in danger of stalling or, put differently, does it have the stamina to become more broad-based? 相似文献
24.
The it Imperative in Business Transformation 总被引:2,自引:0,他引:2
The IT imperative is to construct enterprisewide systems and capabilities needed by business to compete. For IS managers, this means embracing the viewpoint that IT plays a crucial role in building the business of the future. IS and business management must act as true partners, each supporting the other in creating an optimally performing company. 相似文献
25.
Fluorescent additives which allow the determination of droplet temperatures in hydrocarbon fuel sprays have been developed. These systems, which exploit the chemistry of organic exciplexes; should make possible the determination of droplet temperatures within 1 degree C. Two specific systems are described: 3,10-dicyanophenanthrene/diethylaniline over the 20-135 degrees C range, and naphthalene/tetramethyl-p-phenylene diamine over the 140-265 degrees C range. These additives should allow 2-D real-time nonintrusive visualization of the droplet temperatures in an evolving fuel spray. 相似文献
26.
The application of r.f.-sputter etching techniques to the fabrication of grooves in the surface of quartz is reported. This process has been used for the construction of devices which employ the interaction of surface acoustic waves with arrays of well-defined parallel grooves. Devices have been produced with grooves up to 2.5 m deep, which have substantially rectangular profiles and controllable mark-to-space ratios. The groove geometries have been characterized using Talysurf, optical microscopy, SEM and TEM techniques. 相似文献
27.
Stockli MP Han BX Hardek TW Kang YW Murray SN Pennisi TR Piller C Santana M Welton R 《The Review of scientific instruments》2012,83(2):02A732
Since 2009, the Spallation Neutron Source (SNS) has been producing neutrons with ion beam powers near 1 MW, which requires the extraction of ~50 mA H(-) ions from the ion source with a ~5% duty factor. The 50 mA are achieved after an initial dose of ~3 mg of Cs and heating the Cs collar to ~170 °C. The 50 mA normally persist for the entire 4-week source service cycles. Fundamental processes are reviewed to elucidate the persistence of the SNS H(-) beams without a steady feed of Cs and why the Cs collar temperature may have to be kept near 170 °C. 相似文献
28.
CE McMahon 《Canadian Metallurgical Quarterly》1976,2(3):112-115
Despite its impressive rate of growth in the past decades, an increasing amount if dissatisfaction with the area of psychosomatic medicine is reflected in recent literature. The discipline's failures relate to concepts of pathogenesis and therapeutic application of research findings. These failures are explained as a necessary consequence of the philosophical tenet of mind-body dualism which underlies medical theory. It is urged that advocates of psychosomatic medicine give the concept of "holism" meaning at the most fundamental level by establishing a rational basis for theory, or else forsake this line of research for others which yield causal relationships conductive to effective therapy. 相似文献
29.
Kevin Zhang Bhattacharya U. Zhanping Chen Hamzaoglu F. Murray D. Vallepalli N. Yih Wang Bo Zheng Bohr M. 《Solid-State Circuits, IEEE Journal of》2006,41(1):146-151
Column-based dynamic power supply has been integrated into a high-frequency 70-Mb SRAM design that is fabricated on a high-performance 65-nm CMOS technology. The fully synchronized design achieves a 3-GHz operating frequency at 1.1-V power supply. The power supply at SRAM cell array is dynamically switched between two different voltage levels during READ and WRITE operations. Silicon measurement has proven this method to be effective in achieving both good cell READ and WRITE margins, while lowering the overall SRAM leakage power consumption. 相似文献