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Z. Harakeh R. Engels E. Den Exter Blokland R. Scholte A. Vermulst 《Psychology & health》2013,28(7):823-841
This longitudinal study examined the reciprocal effects of the frequency of parent–adolescent communication on tobacco-related issues (smoking-specific communication), and adolescents’ smoking. Participants were 428 Dutch older and younger siblings between 13 and 16 years old. Smoking-specific communication did not affect youth smoking in general; however, among younger, but not older, siblings, smoking-specific communication was associated with a higher likelihood of smoking over time. In addition, when adolescents already smoked parents started to talk more frequently about smoking-related issues with their older and younger adolescents later on. Neither the quality of smoking-specific communication, the quality of parent–adolescent relationship, nor parental smoking moderated these reciprocal effects. In conclusion, prevention campaigns encouraging parents to undertake smoking-specific communication might not be desirable. 相似文献
194.
It is shown that initially sharp interface in AB diffusion couple, above the ordering temperature, can shift with anomalous kinetics, i.e. deviations from the parabolic growth kinetics are possible. The initial slopes of the shift versus time functions can be even unity for large diffusion asymmetry (the ratio of diffusion coefficients of the parent materials in orders of magnitude) and gradually decrease to 0.5 at larger distances (longer times). This is in accordance with earlier results obtained in phase separating systems. It is shown that from the results of simulations the crossover thickness, X*, between the linear and parabolic regimes can also be calculated, and the applicability of the linear–parabolic law is confirmed. Furthermore, it is illustrated that the crossover thickness depends exponentially on the diffusion asymmetry parameter, with the exponent close to the value obtained from analytical estimations. 相似文献
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The compressive deformation and fracture features of Zr59Cu20Al10Ni8Ti3 bulk metallic glassy samples with aspect ratios in the range of 0.67–2.00 have been investigated. The compressive plastic strain of the glass monotonically increases with decreasing aspect ratio, but the maximum strength almost maintains a constant value of 1.77–1.88?GPa. All the compressive shear-band angles are equal to?～40° if modified by the rotation of the primary shear bands. 相似文献
196.
The grain size variation in a gradient surface produced by a punching and recovery process on a Cu-30Ni alloy has been observed by atomic force microscopy. The friction characteristics of the gradient surface in a 3.5 wt% NaCl solution were investigated using a micro-indenter probe, a pin-on-disc type tribometer, a strain sensor and an optical microscope. The results showed that the hardness and grain size can be well represented by the Hall–Petch relationship when the gain size is more than 30?nm. The wear rate, friction coefficient and adhesive force all increase depth below the surface. These variations are attributed to a gradual increasing grain size with depth. The morphologies of the worn track were also studied to understand further the corrosive wear behaviour of gradient surfaces. 相似文献
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A large body of empirical research now shows that people are surprisingly poor at detecting significant changes in visually
presented scenes. This phenomenon is known aschange blindness in vision. A similar phenomenon occurs in audition, but to date no such effect has been documented in touch. In the present
study, we explored the ability of people to detect changes introduced between two consecutively presented vibrotactile patterns
presented over the body surface. The patterns consisted of two or three vibrotactile stimuli presented for 200 msec. The position
of one of the vibrotactile stimuli composing the display was repeatedly changed (alternating between two different positions)
on 50% of the trials, but the same pattern was presented repeatedly on the remaining trials. Three conditions were investigated:
No interval between the patterns, an empty interval between the patterns, and a masked interval between the patterns. Change
detection was near perfect in the no-interval block. Performance deteriorated somewhat in the empty-interval block, but by
far the worst change detection performance occurred in the masked-interval block. These results demonstrate that “change blindness”
can also affect tactile perception. 相似文献