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Previous research on adaptation to visual-motor rearrangement suggests that the CNS represents accurately only 1 visual–motor mapping at a time. This idea was examined in 3 experiments where Ss tracked a moving target under repeated alternations between 2 initially interfering mappings (the "normal" mapping characteristic of computer input devices and a 108° rotation of the normal mapping). Alternation between the 2 mappings led to significant reduction in error under the rotated mapping and significant reduction in the adaptation aftereffect ordinarily caused by switching between mappings. Color as a discriminative cue, interference vs decay in adaptation aftereffect, and intermanual transfer were also examined. The results reveal a capacity for multiple concurrent visual–motor mappings, possibly controlled by a parametric process near the motor output stage of processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
DS Cunningham 《Canadian Metallurgical Quarterly》1993,36(4):193-197
We did a statistical study of 294 strains of Staphylococcus aureus (S. aureus) isolated from skin infections during the period from January of 1989 to December of 1991 in the Department of Dermatology, Kansai Medical University Hospital. We especially examined methicillin-resistant S. aureus (MRSA) from the point of view of incidence, variety of skin infections with MRSA, coagulase type, phase type, and resistance against antimicrobial agents. The frequency of isolation of MRSA has been increasing. In 1991, the proportion of MRSA isolates among all S. aureus strains isolated from skin infections was 41.5%. MRSA was isolated most often from infectious decubitus. Coagulase type II and phage group NT (not typable) MRSA were most frequently isolated. The resistance of MRSA to OFLX and IMP/CS had remarkably increased. Notably, the resistance to MINO was low before 1991. 相似文献
14.
Yi Tao Malshe A.P. Brown W.D. DeReus D.R. Cunningham S. 《Advanced Packaging, IEEE Transactions on》2003,26(3):283-288
In this work, a CO/sub 2/ laser-assisted silicon lid sealing process, utilizing Au80/Sn20 solder, for encapsulating gas breakdown test micro-electro-mechanical structures (MEMS) in a ceramic quad flatpack (CQFP) was studied. Wire bonded MEMS dies were sealed into CQFPs under various gas media, such as air, nitrogen, helium and vacuum. The gas breakdown test results showed a significantly higher breakdown voltage for vacuum packaged parts compared to those packaged in other various gas environments. Hermeticity testing according to MIL-STD-883E showed that the leak rate of the package was below 10/sup -8/ atm cc/s. The bonding was uniform and the bonding strength is believed to be comparable to the tensile strength of Au80/Sn20 solder. 相似文献
15.
This study compared the effects of estrogen (E) on the hyperactivity induced by (+)-3,4-methylenedioxymethamphetamine (MDMA) with E effects on cocaine-evoked hyperactivity in female rats. Sprague-Dawley rats were ovariectomized (OVX); half of them received a 17β-estradiol (E?) implant (OVX + E). Three weeks later, rats received saline, (+)-MDMA (1, 2, or 4 mg/kg) or cocaine (5, 10, or 20 mg/kg), and locomotor activity was monitored. OVX + E rats exhibited greater locomotor hyperactivity in response to both psychostimulants than did OVX rats. The enhanced response to cocaine appeared within 5 min following drug injection whereas the enhanced response to (+)-MDMA was delayed for approximately 30 min. The differential effects of E on hyperactivity may be due to the unique profiles of dopamine (DA) and serotonin (5-HT) in response to (+)-MDMA and cocaine. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
16.
W. S. Holland P. A. R. Ade M. J. Griffin I. D. Hepburn D. G. Vickers C. R. Cunningham P. R. Hastings W. K. Gear W. D. Duncan T. E. C. Baillie E. E. Haller J. W. Beeman 《Journal of Infrared, Millimeter and Terahertz Waves》1996,17(4):669-692
We describe the design and construction of bolometric detectors for SCUBA - the Submillimetre Common-User Bolometer Array for the James Clerk Maxwell Telescope in Hawaii. The instrument contains 131 individual detectors, in two arrays, optimized for the submillimetre atmospheric transmission windows. The detectors are cooled by dilution refrigeration to a temperature of 100 mK, so that the receiver performance will be limited by photon noise from the sky and telescope background in all wavebands. A future paper will describe the performance of the detectors with reference to typical data obtained during the laboratory commissioning period. 相似文献
17.
Cunningham Stacey C.; Corrigan Sheila A.; Malow Robert M.; Smason Ivan H. 《Canadian Metallurgical Quarterly》1993,7(4):246
Assessed the differences between cocaine- and cocaine-plus-alcohol-dependent inpatients along several psychological variables. Of the 144 men that served as Ss, 113 were cocaine dependent and 31 were dependent on both cocaine and alcohol (CD-AD). CD-AD Ss showed significantly more symptoms of depression and anxiety and were more likely to have antisocial and avoidant personality disorders. The CD-AD group scored higher overall on the MMPI clinical scales. Results suggest that patients dependent on both cocaine and alcohol require increased attention to psychopathology during treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
Semiconductor yield improvement: results and best practices 总被引:1,自引:0,他引:1
Cunningham S.P. Spanos C.J. Voros K. 《Semiconductor Manufacturing, IEEE Transactions on》1995,8(2):103-109
The results of a world-wide study on yield improvement are presented. Die yields collected from 21 fabs are transformed via a logit formula and compared. The die yields and die yield improvement rates of the fabs are compared, and manufacturing yield improvement practices are evaluated. Preliminary results of this continuing study indicate that die yield improvement is a function of computer-aided manufacturing practices and statistical process control practices in addition to commonly cited practices such as particle control and advanced manufacturing technology 相似文献
19.
Immunological mimicry between host and microbial proteins has been suggested as a potential mechanism in the development of uveitis in humans. In this study immunological crossreactivity between anti-streptococcal monoclonal antibodies (MAbs) and the human eye was investigated. In indirect immunofluorescence, we demonstrated novel immunological crossreactivity of two anti-streptococcal MAbs (27 and 112) with the rod outer (and inner) segments of the retina of the human eye. In further studies, retinal S-Ag, a uveitogenic protein in the rod outer (and inner) segments, was found to react with the anti-streptococcal MAbs. In addition, several uveitogenic peptides of S-Ag were recognized by the anti-streptococcal MAbs. In the ELISA and Western immunoblot, anti-S-Ag MAbs crossreacted with group A streptococci and the streptococcal M protein further demonstrating sites of antigenic similarity. Homology between the retinal S-Ag and streptococcal M protein was observed in amino acid sequences repeated in the B repeat region of the streptococcal M5 protein. These data show that retinal S-antigen has immunological similarities with streptococcal M protein, a major virulence determinant and strong bacterial cell surface antigen. 相似文献
20.
M Kanayama BW Cunningham JC Weis LM Parker K Kaneda PC McAfee 《Canadian Metallurgical Quarterly》1997,79(11):1710-1720
We investigated the temporal relationship among the biomechanical, radiographic, and histological properties of a posterolateral spinal fusion mass to elucidate the changes in load-sharing of the spinal instrumentation and that of the fusion mass throughout the healing process. Destabilization of the posterior spinal column and transpedicular screw fixation at the segments between the third and fourth and the fifth and sixth lumbar vertebrae was performed in twenty-four sheep. A posterolateral spinal arthrodesis with use of autologous corticocancellous bone graft was done randomly at one of the two segments; the other segment (without bone graft) served as the instrumented control. Six animals each were killed at four, eight, twelve, and sixteen weeks postoperatively. Biomechanical testing showed that the posterolateral fusion mass had increased mechanical stiffness after the fourth week. The strain on the hardware, measured with use of rods instrumented with strain-gauges, decreased significantly (p < 0.01) beginning at eight weeks. Radiographically, three independent observations of each of the six animals at each time-period showed that, although all of the fusion masses were considered solid unions at sixteen weeks, bridging of trabecular bone was noted during only ten of eighteen observations at twelve weeks, three of eighteen observations at eight weeks, and none of eighteen observations at four weeks. Computerized tomography and histomorphometric analyses demonstrated that mineralization in the fusion mass increased in a linear fashion even after eight weeks. Histologically, the fusion mass consisted predominantly of woven bone at eight weeks; thereafter, it was gradually trabeculated. CLINICAL RELEVANCE: We found a great discrepancy between biomechanical stability and histological maturation of the posterolateral fusion mass. The biomechanical properties of a stable spinal fusion preceded the radiographic appearance of a solid fusion by at least eight weeks, suggesting that immature woven bone provided substantial stiffness to the fusion mass. The spinal instrumentation was subjected predominantly to bending stress rather than to axial stress, and the load-sharing of the spinal instrumentation decreased concurrently with the development of the spinal fusion. 相似文献