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71.
Gibbs John C.; Arnold Kevin D.; Ahlborn Helen H.; Chessman Fred L. 《Canadian Metallurgical Quarterly》1984,52(1):37
An intervention involving 60 incarcerated juvenile delinquents (ages 14–18 yrs) yielded significant gains in sociomoral reasoning that were attributable to a dilemma-discussions treatment. The treatment consisted of 8 weekly small-group discussions of sociomoral dilemmas. Ss were pretested on the Sociomoral Reflection Measure (SRM) and the Dilemma Decisions Survey and were assigned to either consensus dilemma-discussion, nonconsensus dilemma-discussion, or no-discussion groups. Pretest results show that Ss initially differed in both sociomoral stage and dilemma opinion. Of the dilemma-discussions Ss, 87.5% were pretested at Modal Stage 2 on the SRM and shifted to Modal Stage 3 on the posttest, whereas only 14.3% of the Modal Stage 2 control Ss did so. Pretest Modal Stage 3 Ss remained at Stage 3 on the posttest. Across the experimental groups, no difference was found between groups where a consensus was required for the discussion and groups having no consensus requirement. Investigations of the possible in-program and postrelease behavioral ramifications of the dilemma-discussions treatment are recommended. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
The role of the mother in the resolution of the rapprochement crisis as it continues into adolescence is examined through the analyses of a 14-year-old boy and his mother. The symptoms of the adolescent were anxiety, poor school performance, and drug abuse. The mother sought treatment for intense anxiety and overwhelming dread when contemplating her future and that of her son. The dynamics of the mother, the nature of the symbiotic bond, and their impact on the inability of the adolescent to effectively disengage from anaclitic parental ties are discussed. The importance of understanding parental dynamics in the analysis of adolescents is stressed from theoretical and clinical viewpoints. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
74.
Chuang HF Cooper SM Meyyappan M Cruden BA 《Journal of nanoscience and nanotechnology》2004,4(8):964-967
Interfacial thermal resistance results of various nanotube and nanofiber coatings, prepared by chemical vapor deposition (CVD) methods, are reported at relatively low clamping pressures. The five types of samples examined include multi-walled and single-walled nanotubes growth by CVD, multi-walled nanotubes grown by plasma enhanced CVD (PECVD) and carbon nanofibers of differing aspect ratio grown by PECVD. Of the samples examined, only high aspect ratio nanofibers and thermally grown multi-walled nanotubes show an improvement in thermal contact resistance. The improvement is approximately a 60% lower thermal resistance than a bare Si-Cu interface and is comparable to that attained by commercially available thermal interface materials. 相似文献
75.
Selenium biotransformations in an insect ecosystem: effects of insects on phytoremediation 总被引:2,自引:0,他引:2
Vickerman DB Trumble JT George GN Pickering II Nichol H 《Environmental science & technology》2004,38(13):3581-3586
Phytoremediation of selenium-contaminated soils may be influenced by higher trophic levels including insects. We examined how selenium affects the behavior, survival, and development of the wasp parasitoid Cotesia marginiventris, parasitizing its natural host, the beet armyworm Spodoptera exigua, feeding on alfalfa, Medicago sativa, irrigated with water containing selenate. X-ray absorption spectroscopy was used to quantify the selenium chemical forms in each trophic level. Alfalfa partially transformed selenate to organoselenium. S. exigua contained only organoselenium, both directly absorbed from M. sativa and transformed from selenate. C. marginiventris cocoons collected shortly after larval emergence contained only organoselenium derived from the host. The surprising finding of trimethylselenonium-like species in adult parasitoids and the cocoons from which they emerged suggests that adults and pharates can detoxify excess selenium through methylation and volatilization. Adult parasitoids do not discriminate against selenium-containing alfalfa, even though alfalfa generates selenium volatiles. Parasitoids raised on selenium-fed larvae emerged later and pupae weighed less than their selenium-free counterparts. We conclude therefore that C. marginiventris can be used to control S. exigua damage to M. sativa being used to remove selenium from soils. Moreover, the presence of such insects may improve phytoremediation by increasing biotransformation of inorganic selenium and release of volatile selenium species. 相似文献
76.
Pettinati Helen M.; Evans Frederick J.; Orne Emily C.; Orne Martin T. 《Canadian Metallurgical Quarterly》1981,90(4):345
Evaluated memory for successful and unsuccessful responses to hypnotic suggestions in partially amnesic Ss and in those Ss with normal forgetting. Two analyses (278 undergraduates) demonstrated that highly hypnotizable Ss experiencing partial posthypnotic amnesia tended to show no selective recall for their successes or failures during amnesia, whereas the remainder of the Ss showed definite selective recall of hypnotic success posthypnotically. These findings support F. J. Evans and J. F. Kihlstrom's (see record 1974-06307-001) hypothesis that posthypnotic amnesia involves a disruption of memory organization and suggest that the phenomenon may be mediated by a restriction in the use of normally employed retrieval cues. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
In this study, a range of commercial whey protein products were characterized by the use of size-exclusion chromatography coupled with a multi-angle laser light scattering (MALLS) detector. The MALLS system detected some very large-sized material that eluted close to void volume in all samples; this material was hardly detected by concentration detector. It was demonstrated by chitosan treatment that this peak was very small lipid globules or phospholipids, which gave the residual "cloudy" appearance in upper layers after ultracentrifugation of whey products. Composition, molecular weight, and the photo diode array (PDA) spectrum (200 to 400 nm) of the major protein peaks, including: beta-lactoglobulin (BLG), alpha-lactalbumin (ALA), bovine serum albumin (BSA), immunoglobulin G (IgG) and some minor components were analyzed. The molecular weight of BLG, ALA, BSA, and IgG peaks in whey protein isolates (WPI) were 2.3 to 3.7 x 10(4), 1.4 to 1.6 x 10(4), 4.8 to 6.7 x 10(4), and 1.2 to 2.5 x 10(5) Da, respectively. Compared with WPI, WPC has similar major proteins, but more large-sized residual lipid material and different minor constituents such as lactose and nonprotein nitrogen, depending on various commercial samples and protein content. An improved TCA-precipitation method was applied to quantify glycomacropeptide (GMP) in whey proteins, which demonstrated that there was a very low concentration of GMP in WPI manufactured using an ion-exchange process. The molecular weight of GMP was found to be approximately 8600 Da. Size-exclusion chromatography MALLS was demonstrated to be a powerful technique for detailed analysis of the molecular weight of various proteins, aggregates and minor components, such as GMP, in whey protein products. 相似文献
78.
Mobile technologies offer new opportunities for childrens educational activities in that they can be used across different locations and times. Naturally, some instances of mobile technology use will necessitate, or be enhanced by, the sharing of information. Social interaction is important for sharing ideas, constructing and shaping understanding and fundamental for educational development. However the physical size of mobile technologies presents interesting challenges when designing for collaborative activities. When designing mobile technologies the importance of collaborative tasks has often been overlooked. The replacement of low-tech artefacts with digital devices, for supporting multiple users, can inhibit the shareability of information. We present three projects where mobile technologies have been used as part of a larger mixed reality experience. Novel technologies were used to support childrens collaborative activities in storytelling, an adventure game and during an outdoor field trip. Interaction with mobile devices within each project is reviewed and the authors highlight important considerations for their design and use across multiple contexts. 相似文献
79.
The separation of the individual contributions of aerosol and gases to the total attenuation of radiation through the atmosphere has been the subject of much scientific investigation since remote sensing experiments first began. We describe a new scheme to account for the spectral variation of the aerosol extinction in the inversion of transmission data from occultation measurements. Because the spectral variation of the aerosol extinction is generally unknown,the inversion problem is underdetermined and cannot be solved without a reduction in the number of unknowns in the set of equations used to describe the attenuation at each wavelength. This reduction can be accomplished by a variety of methods, including use of a priori information, the parameterization of the aerosol spectral attenuation, and the specification of the form of the aerosol size distribution. We have developed and implemented a parameterization scheme based on existing empirical and modeled information about the microphysical properties of aerosols. This scheme employs the eigenvectors from an extensive set of simulations to parameterize the aerosol extinction coefficient for incorporation into the inversion algorithm. We examine the accuracy of our method using data sets containing over 24,000 extinction spectra and compare it with that of another scheme that is currently implemented in the Polar Ozone and Aerosol Measurement (POAM) satellite experiment. In simulations using 80 wavelengths in the UV-visible-near-IR spectral range of the Stratospheric Aerosol and Gas Experiment III (SAGE) instrument, we show that, for our optimal parameterization, errors below 1% are observed in 80% of cases, whereas only approximately 20% of all cases are as accurate as this in a quadratic parameterization employing the logarithm of the wavelength. 相似文献
80.
Samarium and manganese-doped lead titanate ceramic fiber/epoxy 1-3 composite for high-frequency transducer application 总被引:1,自引:0,他引:1
Li K Chan HL Choy CL 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2003,50(10):1371-1376
Samarium- (Sm) and manganese- (Mn) doped lead titanate ceramic fibers with a diameter of 35 /spl mu/m were prepared using a sol-gel method. The X-ray diffraction pattern shows that the fibers have a pure perovskite structure. The 1-3 composite disks with a thickness of 31-41 /spl mu/m and with ceramic volume fraction of /spl sim/0.68 have been prepared using the samarium and manganese doped lead titanate (PSmT) fibers. The resonance characteristics of the poled composite disks were measured. A focused transducer was fabricated using a concave 1-3 composite disk with nonuniform thickness in order to enhance its bandwidth. The insertion loss (IL), pulse-echo response and frequency spectrum of the composite transducer were measured. The center frequency of the transducer was /spl sim/31 MHz with a -3 dB bandwidth of /spl sim/123% and a low IL of 29.3 dB. 相似文献