Accessory child safety harnesses: Do the risks outweigh the benefits?

Accessory child safety harnesses are available in some countries as alternative restraints for young children or as an accessory restraint used with booster seats. Their use, in Australia at least, is becoming more common. There have been concerns that the risk of misuse of these restraints outweighs any potential benefit this system might have over a retractable lap-shoulder belt system used with a booster seat. However to date there is no evidence to confirm or deny this. This study used laboratory simulated frontal crash tests to examine the performance of accessory child safety harness systems compared to the lap-shoulder belt when used alone and when used with two common designs of Australian booster seat. The performance of the child safety harness system when misused was also investigated. The results demonstrate that the correctly used child safety harness system performed no better than the lap-shoulder system, and in fact allows for a greater risk of submarining. Furthermore, one common form of child safety harness misuse, where the harness is over-tightened causing the lap belt to be positioned high over the abdomen, allowed extremely undesirable dummy motion. This involved gross submarining and direct contact between the harness system and the dummy's neck. These findings suggest that the risks associated with accessory child safety harness systems most likely outweigh any potential benefits, in frontal impacts at least.     

The role of K+ and H+ transport systems during glucose‐ and H2O2‐induced cell death in Saccharomyces cerevisiae

Glucose, in the absence of additional nutrients, induces programmed cell death in yeast. This phenomenon is independent of yeast metacaspase (Mca1/Yca1) and of calcineurin, requires ROS production and it is concomitant with loss of cellular K⁺ and vacuolar collapse. K⁺ is a key nutrient protecting the cells and this effect depends on the Trk1 uptake system and is associated with reduced ROS production. Mutants with decreased activity of plasma membrane H⁺‐ATPase are more tolerant to glucose‐induced cell death and exhibit less ROS production. A triple mutant ena1‐4 tok1 nha1, devoid of K⁺ efflux systems, is more tolerant to both glucose‐ and H₂O₂‐induced cell death. We hypothesize that ROS production, activated by glucose and H⁺‐ATPase and inhibited by K⁺ uptake, triggers leakage of K⁺, a process favoured by K⁺ efflux systems. Loss of cytosolic K⁺ probably causes osmotic lysis of vacuoles. The nature of the ROS‐producing system sensitive to K⁺ and H⁺ transport is unknown. Copyright © 2010 John Wiley & Sons, Ltd.     

Linking learning goals and educational resources through interactive concept map visualizations

Concept browsing interfaces can help educators and learners to locate and use learning resources that are aligned with recognized learning goals. The Strand Map Service enables users to navigate interactive visualizations of related learning goals and to request digital library resources aligned with learning goals. These interfaces are created using a programmatic Web service interface that dynamically generates interactive visual components. Preliminary findings suggest that these library interfaces appear to help users stay focused on the scientific content of their information discovery task, as opposed to focusing on the mechanics of searching.     

A Reinforcement Learning Algorithm in Cooperative Multi-Robot Domains

Reinforcement learning has been widely applied to solve a diverse set of learning tasks, from board games to robot behaviours. In some of them, results have been very successful, but some tasks present several characteristics that make the application of reinforcement learning harder to define. One of these areas is multi-robot learning, which has two important problems. The first is credit assignment, or how to define the reinforcement signal to each robot belonging to a cooperative team depending on the results achieved by the whole team. The second one is working with large domains, where the amount of data can be large and different in each moment of a learning step. This paper studies both issues in a multi-robot environment, showing that introducing domain knowledge and machine learning algorithms can be combined to achieve successful cooperative behaviours.     

Interfacial reactions of Sn-Ag-Cu solders modified by minor Zn alloying addition

The near-ternary eutectic Sn-Ag-Cu alloys have been identified as leading Pb-free solder candidates to replace Pb-bearing solders in microelectronic applications. However, recent investigations on the processing behavior and solder joints reliability assessment have revealed several potential reliability risk factors associated with the alloy system. The formation of large Ag₃Sn plates in Sn-Ag-Cu joints, especially when solidified in a relatively slow cooling rate, is one issue of concern. The implications of large Ag₃Sn plates on solder joint performance and several methods to control them have been discussed in previous studies. The minor Zn addition was found to be effective in reducing the amount of undercooling required for tin solidification and thereby to suppress the formation of large Ag₃Sn plates. The Zn addition also caused the changes in the bulk microstructure as well as the interfacial reaction. In this paper, an in-depth characterization of the interfacial reaction of Zn-added Sn-Ag-Cu solders on Cu and Au/Ni(P) surface finishes is reported. The effects of a Zn addition on modification of the interfacial IMCs and their growth kinetics are also discussed.     

Parental divorce during early adolescence in Caucasian families: The role of family process variables in predicting the long-term consequences for early adult psychosocial adjustment.

The relationship between parental divorce occurring during adolescence and young adult psychosocial adjustment was examined, as was the role of family process variables in clarifying this relationship. Participants were young Caucasian adults from divorced (n?=?119) and married (n?=?123) families. Assessments were conducted during adolescence and 6 years later during early adulthood. Young adults from married families reported more secure romantic attachments than those from divorced families; however, differences were not evident in other domains of psychosocial adjustment after demographic variables were controlled. Three family process variables (parent–adolescent relationship, interparental conflict, and maternal depressive symptoms) were examined as potential mediators and moderators of the association between parental divorce and young adult adjustment. No evidence supporting mediation or moderation was found; however, the parent–adolescent and parent–young adult relationships, particularly when the identified parent was the father, emerged as significant predictors of young adult psychosocial adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender differences in altruistic reputation: Are they artifactual?

Tested the notion that observed sex differences in children's altruistic reputations that favor girls are due to sex-biased items found in commonly used peer-assessment measures. A gender-fair assessment of altruistic reputation was attempted by including items that were empirically derived examples of masculine, feminine, and gender-neutral prosocial behaviors. These items were based on prosocial incidents reported by 65 5th graders. 123 additional 5th graders were asked to respond to the new items by nominating 2 classmates most likely to engage in prosocial behavior or by indicating which sex was most likely to perform the behaviors. Results show that, overall, females were judged to be more altruistic than males. However, endorsement differed across item content: Males were selected more often for masculine items and females more often for feminine and sex-neutral items. In general, males endorsed males for helpful behaviors and females endorsed females. The gender-rating form of the test produced responses more closely related to the empirically based item-gender-content classes than did the peer-nomination form. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)