Individual and situational factors that influence the efficacy of personalized feedback substance use interventions for mandated college students.

Little is known about individual and situational factors that moderate the efficacy of personalized feedback interventions (PFIs). Mandated college students (N = 348) were randomly assigned either to a PFI delivered in the context of a brief motivational interview (BMI; n = 180) or to a written PFI only (WF) condition and were followed up at 4 months and 15 months postintervention. The authors empirically identified heterogeneous subgroups utilizing mixture modeling analysis based on heavy episodic drinking and alcohol-related problems. The 4 identified groups were dichotomized into an improved group (53.4%) and a nonimproved group (46.6%). Logistic regression results indicated that the BMI was no more efficacious than the WF across all mandated students. However, mandated students who experienced a serious incident requiring medical or police attention and those with higher levels of alcohol-related problems at baseline benefited more from the BMI than from the WF. It may be an efficacious and cost-effective approach to provide a written PFI for low-risk mandated students and an enhanced PFI with a BMI for those students who experience a serious incident or have higher baseline alcohol-related problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Field synergy principle analysis on fully developed forced convection in porous medium with uniform heat generation

In the presence of uniform heat source, the energy equation for forced convective heat transfer in porous medium between two parallel plates is solved for fully developed flow. Field synergy analysis is performed with emphasis on the intersection angle between the velocity vector and temperature gradient vector with the inclusion of heat generation. Maximum local intersection angle corresponds to location with the highest resistance to heat convection. Relationship between Nusselt number and field synergy for forced convection in the presence of heat generation is studied. It is necessary to define a modified intersection angle in order to compare the wall heat transfer coefficient for convective heat transfer processes with uniform heat source.     

High-peak-power 2nd-harmonic l.s.a. sources

Results are presented which indicate that the upper frequency range of l.s.a. oscillators can be extended by extracting power at the 2nd-harmonic frequency. By selectively loading the 2nd-harmonic frequency of an X-band l.s.a. oscillator, up to 170 W peak power with 4.8% efficiency at 17.5 GHz has been obtained.     

Influence of maltodextrin addition on the freeze-dry stability of β-lactoglobulin-based emulsions with controlled electrostatic and/or steric interactions

Three types of emulsions (β-Lg-, β-Lg-pectin-, and β-Lg-ι-carrageenan-coated emulsions) with controlled electrostatic and/or steric interactions were prepared, and then examined for their freeze-dry stability in the absence or presence of 6% maltodextrin (MD). In the absence of MD, all emulsions were highly unstable to freeze-drying, nevertheless, the β-Lg-pectin-coated emulsions (d ₃₂ =5.37, d ₄₃ =35.11 μm) that were stabilized mostly by steric repulsion showed better stability than the other 2 emulsions (no dried power was obtained). The freeze-dry instability of all emulsions was improved with MD addition, particularly in the β-Lg- (d ₄₃ =1.10 μm) and β-Lg-ι-carrageenan-coated emulsions (d ₄₃ =0.58 μm) that were stabilized by electrostatic repulsive force. In the presence of MD, the β-Lg-ι-carrageenan-coated emulsions showed the highest stability to freeze-drying, which was attributed to the cooperative impact of steric and electrostatic repulsion. This study implicates that the major mechanism for stabilizing emulsions against freeze-drying could be different depending on the absence or presence of MD.     

Performance Comparison of a SSVEP BCI Task by Individual Stereoscopic 3D Susceptibility

This study aimed at investigating the differences in brain–computer interface (BCI) task performance between 2D and 3D displays depending on their individual susceptibility to stereoscopic 3D. Eleven female and 10 male participants attempted a steady-state visually evoked potential BCI navigation task in a virtual home environment with and without 3D views. Participants were categorized into fatigued and unfatigued groups, depending on their individual susceptibility to 3D, which was characterized using a subjective evaluation method for 3D visual fatigue. The task completion time for the fatigued group under the 3D conditions was significantly delayed relative to the 2D mode. In contrast, a significantly decreased completion time was observed in the 3D view relative to the 2D view for the unfatigued group. The averaged positive predictive value significantly increased in the 3D mode relative to the 2D one for the unfatigued group only. These results are expected to provide a practical implication for enhancing BCI task performance in light of individual vulnerability to 3D.     

Self‐Assembled In‐Plane Growth of Mg2SiO4 Nanowires on Si Substrates Catalyzed by Au Nanoparticles

In‐plane growth of Mg₂SiO₄ nanowires on Si substrates is achieved by using a vapor transport method with Au nanoparticles as catalyst. The self‐assembly of the as‐grown nanowires shows dependence on the substrate orientation, i.e., they are along one, two, and three particular directions on Si (110), (100), and (111) substrates, respectively. Detailed electron microscopy studies suggest that the Si substrates participate in the formation of Mg₂SiO₄, and the epitaxial growth of the nanowires is confined along the Si <110> directions. This synthesis route is quite reliable, and the dimensions of the Mg₂SiO₄ nanowires can be well controlled by the experiment parameters. Furthermore, using these nanowires, a lithography‐free method is demonstrated to fabricate nanowalls on Si substrates by controlled chemical etching. The Au nanoparticle catalyzed in‐plane epitaxial growth of the Mg₂SiO₄ nanowires hinges on the intimate interactions between substrates, nanoparticles, and nanowires, and our study may help to advance the developments of novel nanomaterials and functional nanodevices.     

Fatigue and rutting performance of lime-modified hot-mix asphalt mixtures

This paper describes the effect of lime on composite hot-mix asphalt (HMA) mixtures of aggregate and asphalt binder evaluated using viscoelastic continuum damage analysis, which is based on predicting the effective stress vs. strain equations and microcrack growth. The performance characteristics evaluated in this study included fatigue cracking and rutting resistance in both moisture-damaged and undamaged states. The test methods used in this evaluation were the dynamic modulus test for stiffness characterization, the direct tension test for fatigue cracking characterization, and the triaxial repeated-load permanent deformation test for rutting characterization. The main contribution of this paper is the demonstration of advanced test methods and models that can be used to evaluate the performance of various mixtures with respect to the fatigue damage and rutting performance.     

Simple synthesis of ZnS nanoparticles in alkaline medium

ZnS nanoparticles were successfully synthesized by reflux under an alkaline medium. The nanoparticles were characterized by using X-Ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The optical properties of ZnS nanoparticles were examined by photoluminescence (PL) spectrum. The result shows that the as-synthesized ZnS nanoparticles had a cubic phase. SEM image shows that ZnS nanoparticles are basically in spherical shape and are homogeneous. The particle size was found to be in the range of 18 nm.     

Monolithic GaAs photoreceiver for high-speed signal processing applications

High-speed planar monolithically integrated GaAs photoreceivers have been fabricated by selective ion implantation into SI GaAs substrates. Their fabrication is fully compatible with existing GaAs LSI process schedules. A receiver upper cutoff frequency of 1.5 GHz and sensitivity of 112 V/W have been measured. The application of these devices in short-haul high-bit-rate data communication systems has been demonstrated in a 560 Mbit prototype optical data link, using packaged and fibre-coupled devices.