Influence of family factors and supervised alcohol use on adolescent alcohol use and harms : similarities between youth in different alcohol policy contexts

Objective: Harm-minimization policies suggest that alcohol use is a part of normal adolescent development and that parents should supervise their children's use to encourage responsible drinking. Zero-tolerance policies suggest that all underage alcohol use should be discouraged. This article compared hypotheses derived from harm-minimization and zero-tolerance policies regarding the influence of family context and supervised drinking on adolescent alcohol use and related harms among adolescents in Washington State, USA, and Victoria, Australia. two states that have respectively adopted zero-tolerance and harm-minimization policies.

Method: Representative samples of seventh-grade students (N = 1,945:989 females) were recruited from schools in each state. Students completed comprehensive questionnaires on alcohol use, related problem behaviors, and risk and protective factors annually from 2002 to 2004 when they were in ninth grade.

Results: Relationships between family context and alcohol use and harmful use were very similar in both states. Adult-supervised settings for alcohol use were associated with higher levels of harmful alcohol consequences. Adult-supervised alcohol use mediated the links between favorable parental attitudes to alcohol use and ninth-grade alcohol use for students in both states.

Conclusions: Despite policy differences in the two states, relationships between family context variables and alcohol use and harmful use are remarkably similar. Adult-supervised settings for alcohol use resulted in higher levels of harmful alcohol consequences, contrary to predictions derived from harm-minimization policy. Findings challenge the harm-minimization position that supervised alcohol use or early-age alcohol use will reduce the development of adolescent alcohol problems.

Engaging and effective asynchronous online discussion forums

Discussion is usually considered a powerful tool for the development of pedagogical skills such as critical thinking, collaboration and reflection. In the last few years, an online asynchronous discussion forum has become an integral part of teaching and learning in tertiary education. However, there are considerable challenges involved in designing discussion forum for learning and teaching arrangements that can support desired learning outcomes. The study analysed the factors that affect the level of the student participation in the online discussion forums with emphases on some of the critical issues that should be taken into account when designing online discussions forums that can support desired learning outcomes. We show that the course instructor roles and level of participations in the discussion forum particularly determines the overall level of discussion among the learning communities.

Online learning environment : taxonomy of asynchronous online discussion forums

Due to its perceived benefits, asynchronous discussion forums have become progressively popular in higher education. The ultimate goal of developing an asynchronous discussion forum is to create an online learning environment that will achieve high levels of learning. This paper reviews the exiting literature and develops taxonomy of the asynchronous discussion forums with the aims of increasing the understanding and awareness of various types of asynchronous discussion forums. The taxonomy will help increase the online course designers' ability to design more effective learning experiences for student success and satisfaction. It will also help researchers to understand the features of the various asynchronous discussion forums.

Immobilization of large, aliovalent cations in the small-pore zeolite K-natrolite by means of pressure

High-pressure ion exchange of small-pore zeolite K-natrolite allows immobilization of nominally non-exchangeable aliovalent cations such as trivalent europium. A sample exchanged at 3.0(1) GPa and 250 °C contains about 4.7 Eu^III ions per unit cell, which is equivalent to over 90 % of the K⁺ cations being exchanged.

Corrosion properties of a RF-magnetron-sputtered TiN coating deposited on 316L stainless steel

The effect of rf-power in the range from 100 to 200 W on the electrochemical properties of TiN coatings deposited on 316L stainless steel was investigated by using various electrochemical techniques in a 3.5-wt\% NaCl solution. Surface analyses were also conducted to analyze the coating characteristics. X-ray diffraction (XRD) and atomic force microscopy (AFM) analyses confirmed that increasing the rf-power led to a preferred orientation of the TiN(200) microstructure and decreased the surface roughness. The potentiodynamic test results confirmed the passive behavior of all of the specimens with low passive current densities and demonstrated that the effective pitting resistance of the TiN coatings increased with increasing rf-power. The electrochemical impedance spectroscopy (EIS) tests showed that the TiN films deposited with high rf-power had excellent corrosion resistance during an immersion time of 720 h due to their high total resistance and low porosity.

Effect of Ag addition on the corrosion properties of Sn-based solder alloys

Corrosion properties of three different Sn-Ag lead free solder alloys have been investigated in 0.3 wt% Na₂SO₄ solution as corrosive environment. As cast solder alloy was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Volume fractions of the Ag₃Sn in the solders were determined by image analysis technique. Pitting potential and corrosion potential for the alloys were determined by potentiodynamic tests. Electrochemical impedance spectroscopy (EIS) was carried out to measure the film and charge transfer resistance. Alloys with lower Ag content have been found as better corrosion resistance material.

Triethyl and tributyl phosphite as flame-retarding additives in Li-ion batteries

This study examined the influence of triethyl and tributyl phosphite (TEP and TBP) additives on the electrochemical performance of lithium-ion cells. The cell performance of the TEP- and TBP-containing electrolytes was evaluated by cyclic voltammetry, thermogravimetric analysis, electrochemical impedance spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy. The flammability of the electrolytes was also investigated by measuring the self-extinguishing time of the electrolytes. The results showed that the TEP and TBP additives suppressed the flammability of the electrolyte, with a significant improvement in cell performance observed for the TEP additive. In addition, TEP and TBP additives improved the thermal stability of the battery and its electrochemical cell performance. Overall, 5 wt% TEP and TBP can be used as a flame-retarding additive to improve the cell performance of Li-ion batteries due to the decrease in cell impedance and SEI formation.