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31.
Su Vida, Su Salud/Your Life, Your Health is a community program to increase participation in breast and cervical cancer screening. This program illustrates the diffusion of an innovative outreach strategy from a research environment to two local health departments. The program uses A Su Salud, the communication model in which positive role models are featured in the media, and community volunteers who give positive social reinforcement. Local health departments in Galveston and Corpus Christi, TX, were selected to implement the model because of excessive mortality rates in the region and the departments' adequate level of resources and commitment. Over an 18-month period, 54 stories of role models appeared in the media in Corpus Christi, and 60 appeared in Galveston. There were 490 volunteers active in Corpus Christi and 279 in Galveston. Of 365 inquiries to the Corpus Christi program, 35 percent were from the Mexican American target group of women ages 40-70. Of 1,457 women who contacted the Galveston program, 9 percent were from the African American target group ages 40-70. Local health departments are well-suited to participation in cancer control research applications because they have direct access to high-risk populations and have the authority to institutionalize effective interventions. 相似文献
32.
Abstract The SelfSpell programs provide a multi-media environment for dyslexic children which uses synthesised speech to augment the written text. In earlier research we established that by encouraging users to enter a rule to help them remember how to spell each word, SelfSpell was very effective in improving spelling ability. The evaluation study reported here confirmed the efficacy of the rule-based approach using a group of 11-year-old dyslexic children with severe impairments in spelling. Of particular theoretical significance, however, was the finding that use of a mastery learning technique for learning spellings was just as effective as the rule-based approach. These findings are interpreted in the light of Frith's influential framework for the development of reading and spelling ability. It is suggested that the multimedia presentation approach may provide a uniquely effective method for helping dyslexic children to acquire the 'alphabetic' stage of linguistic processing. 相似文献
33.
Slater D.B. Jr. Enquist P.M. Hutchby J.A. Reed F.E. Morris A.S. Kolbas R.M. Trew R.J. Lujan A.S. Swart J.W. 《Photonics Technology Letters, IEEE》1993,5(7):791-794
An AlGaAs/GaAs nan heterojunction bipolar transistor (HBT) laser driver circuit and a pseudomorphic InGaAs/GaAs/AlGaAs graded index single-quantum-well (SQW) laser have been laterally integrated to maintain surface planarity using selective organometallic vapor-phase epitaxy (OMVPE) regrowth of the HBT. The self-aligned HBTs exhibit a DC current gain of 30 and an f t (f max ) of 45(60) GHz. The 980-nm lasers exhibit room-temperature threshold current densities as low as 420(320) A/cm2 for CW (pulsed) operation. The cavities are 40(7) μm×500 μm and have less than 1(2) Ω of series resistance. SPICE simulations of the integrated driver indicate that operating speeds of over 10 Gb/s are possible 相似文献
34.
The behavior during creep in shear of eutectic indium-tin joints on copper and nickel substrates was examined in order to
determine the effect of creep deformation on the microstructure of the alloy. Primary creep was absent in all the samples
tested. The stress exponent at 20° C was much higher for samples on nickel than for those on copper, indicating a different
creep deformation mechanism. Also, the microstructure within the indium-tin joints differed significantly with a change of
substrate. Samples with a nickel substrate showed a colony microstructure that was not observed in those with a copper substrate.
Thus, eutectic morphology is important in determining deformation mechanism during creep. The microstructure within the joints
in tested and untested regions of the samples was effectively the same. This is quite distinct from the behavior of eutectic
lead-tin observed in previous work. Lead-tin formed a recrystallized band of material along a region of concentrated shear
deformation. While the deformation pattern in the indium-tin samples appeared to be the same as for lead-tin, the microstructural
changes did not occur. This implies that the behavior observed in lead-tin is not universal to eutectic alloys. 相似文献
35.
36.
Baars J.W.M. Greve A. Hein H. Morris D. Penalver J. Thum C. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1994,82(5):687-696
The “Millimeter Radio Telescope” (MRT) is operated by the Institute for Radio Astronomy in the millimeter range (IRAM) and is located at 2850-m altitude in the Sierra Nevada, near Granada, Spain. It is a reflector antenna of 30-m diameter with a surface accuracy of 0.08 mm and a pointing accuracy of better than 2 arcsec. The telescope is equipped with sensitive receivers for the atmospheric windows between 0.8- and 7-mm wavelength. The authors describe the optics layout of the receiver and calibration system, which allows simultaneous observations at a number of frequencies. The special design aspects of the antenna, in particular the control of thermal deformations and the achievement of a high reflector and pointing accuracy are described. The authors compare the design computations with the characteristics of the telescope, derived from several years of operation and optimization. The success of the design is demonstrated by observational experience. The authors conclude the paper with a short review of some of the astronomical results obtained with the telescope 相似文献
37.
P Barrett G Davidson DG Hazlerigg MA Morris AW Ross PJ Morgan 《Canadian Metallurgical Quarterly》1998,139(1):163-171
38.
Levy H. Messinger T.G. Morris R.J.T. 《IEEE transactions on pattern analysis and machine intelligence》1996,22(11):827-838
Given N request streams and L⩽N LRU caches, the cache assignment problem asks to which cache each stream should be assigned in order to minimize the overall miss rate. An efficient solution to this problem is provided, based on characterizing each stream using the stack reference model and characterizing the interaction of the streams using a bursty stream model. It is shown that for Bernoulli (purely random) mixing of streams, the optimal cache assignment is to have one cache per stream. In practice streams are mixed in a way that is much “burstier” than can be represented by the Bernoulli model. Therefore a method is presented for superposition of bursty streams. The performance of the methods developed for bursty stream superposition and cache assignment are tested using trace data obtained from the database system DB2. The resulting cache assignment recommendations are then applied to the DB2 system, and considerable performance improvement is found to result 相似文献
39.
BK Berdiev KH Karlson B Jovov PJ Ripoll R Morris D Loffing-Cueni P Halpin BA Stanton TR Kleyman II Ismailov 《Canadian Metallurgical Quarterly》1998,75(5):2292-2301
The molecular composition of a core conduction element formed by the alpha-subunit of cloned epithelial Na+ channels (ENaC) was studied in planar lipid bilayers. Two pairs of in vitro translated proteins were employed in combinatorial experiments: 1) wild-type (WT) and an N-terminally truncated alphaDeltaN-rENaC that displays accelerated kinetics (tauo = 32 +/- 13 ms, tauc = 42 +/- 11 ms), as compared with the WT channel (tauc1 = 18 +/- 8 ms, tauc2 = 252 +/- 31 ms, and tauo = 157 +/- 43 ms); and 2) WT and an amiloride binding mutant, alphaDelta278-283-rENaC. The channels that formed in a alphaWT:alphaDeltaN mixture fell into two groups: one with tauo and tauc that corresponded to those exhibited by the alphaDeltaN-rENaC alone, and another with a double-exponentially distributed closed time and a single-exponentially distributed open time that corresponded to the alphaWT-rENaC alone. Five channel subtypes with distinct sensitivities to amiloride were found in a 1alphaWT:1alphaDelta278-283 protein mixture. Statistical analyses of the distributions of channel phenotypes observed for either set of the WT:mutant combinations suggest a tetrameric organization of alpha-subunits as a minimal model for the core conduction element in ENaCs. 相似文献
40.
When people are allowed freedom to volunteer or withhold information, they can enhance the accuracy of their memory reports substantially relative to forced-report performance. A theoretical framework addressing the strategic regulation of memory reporting is put forward that delineates the mediating role of metamemorial monitoring and control processes. Although the enhancement of memory accuracy is generally accompanied by a reduction in memory quantity, experimental and simulation results indicate that both of these effects depend critically on (a) accuracy incentive and ( b ) monitoring effectiveness. The results are discussed with regard to the contribution of metamemory processes to memory performance, and a general methodology is proposed that incorporates these processes into the assessment of memory-accuracy and memory-quantity performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献