Electrostatic Shaping of Magnetic Transition Regions in La_{0.7}Sr_{0.3}MnO_{3}.

We report a magnetic transition region in La_{0.7}Sr_{0.3}MnO_{3} with gradually changing magnitude of magnetization, but no rotation, stable at all temperatures below T_{C}. Spatially resolved magnetization, composition and Mn valence data reveal that the magnetic transition region is induced by a subtle Mn composition change, leading to charge transfer at the interface due to carrier diffusion and drift. The electrostatic shaping of the magnetic transition region is mediated by the Mn valence, which affects both magnetization by Mn^{3+}-Mn^{4+} double exchange interaction and free carrier concentration.

Improving protection system for wheelchair-seated occupants in vehicle side impacts.

Objective: Previous research on occupant protection systems for wheelchair-seated occupants focused on frontal impacts, while similar studies on side impacts are very limited. The objective of this study was to identify the major injury concerns for wheelchair-seated occupants in side impacts and develop restraint systems to mitigate such injury concerns.Methods: Seven sled tests in side impact conditions were first conducted at 30 km/h with a 24 g peak deceleration. An ES2-RE ATD and surrogate wheelchair base (SWCB) were used in all tests, which varied armrest design, width of the SWCB, and wheelchair tiedown conditions. These sled tests set up the baseline performance and provided validation data for computational models. A set of validated MADYMO models were then used to investigate the safety concerns and potential restraint solutions for wheelchair-seated occupants in side impacts. Simulations covered nearside and farside impacts, inboard or outboard D-ring locations, varied wheelchair locations relative to the side door, varied seatbelt anchorage locations, and a few Center Airbag To Contain Humans (CATCH) designs. Finally, another set of sled tests were conducted to demonstrate the effectiveness of varied CATCH designs for protecting wheelchair-seated occupants in farside impacts.Results: Simulations suggested that wheelchair-seated occupants might fall from the wheelchair in farside impacts, while in nearside impacts the seatbelt and curtain airbag can provide reasonable protection to occupants using wheelchairs. The CATCH design, a curtain airbag mounted to the roof centerline with tethers attached outboard of the wheelchair station, was effective at preventing the ATD from falling off the wheelchair. Results from sled tests to iterate CATCH parameters confirmed that the concept was effective at retaining occupants seated in wheelchairs under farside impact loading.Conclusions: This study is the first to investigate wheelchair-seated occupant protection in both nearside and farside impacts. The injury concerns identified in farside impacts and the CATCH design can potentially help improve the protection of wheelchair-seated occupants in side impacts in the future. The CATCH design has potential to improve farside protection for occupants in traditional seating.

Restraint systems considering occupant diversity and pre-crash posture.

OBJECTIVE: Use volunteer data and parametric finite element (FE) human body models to investigate how restraint systems can be designed to adapt to a diverse population and pre-crash posture changes induced by active safety features. METHODS: Four FE human models were generated by morphing the midsize male GHBMC simplified model into geometries representing a midsize male, midsize female, short obese female (BMI 40 kg/m2), and large obese male (BMI 40 kg/m2) based on statistical skeleton and body shape geometry models. Each human model was positioned in a generic vehicle driver environment using two occupant pre-crash postures based on volunteer test results including one resulting from 1-g abrupt braking events. Improved restraint designs were manually developed for each occupant model in a 56 km/h frontal crash condition by adding a knee airbag, adjusting the shoulder belt load limit, steering column force, and driver airbag properties (tethers, inflation, and vent size). The improved designs were then tested at both pre-crash postures. Injury risks for the head, neck, chest, and lower extremities were analyzed. RESULTS: Human size and shape dominated the occupant injury measures, while the pre-crash-braking induced posture had minimal effects. Some of the safety concerns observed for large occupants include head strike-through the airbag and a conflict between head and chest injuries, which were mitigated by a stiffer restraint system with properly-tuned driver airbag. Chest injuries were a prominent safety concern for female occupants, mitigated by a softer seatbelt and smaller airbag size near the chest. Obese occupants exhibited a higher likelihood of lower extremity injuries indicating a need for a knee airbag. A diverse set of improved restraint designs were effective in lowering injury risks, indicating that restraint adaptability is necessary for accounting for occupant diversity. CONCLUSIONS: This study investigated the effects of occupant size and shape variability, posture, and restraint design on injury risk for high-speed frontal crashes. More forward initial postures due to active safety features may decrease head, neck, and lower extremity injury risk, but may also increase chest injury risk. Safety concerns observed for large occupants include head strike-through and a conflict between head and chest injuries. Obese occupants had higher knee-thigh-hip injury risk. New restraints that adapt to occupant size and body shape may improve crash safety for all occupants. Further investigation is needed to confirm and extend the findings of this study.

Toward a refined view of aggressive fantasy as a risk factor for aggression: interaction effects involving cognitive and situational variables.

Over three decades of research have established a positive connection between fantasizing about aggression and enacting aggression. Such findings have provided strong evidence against the catharsis view of aggressive fantasy. However, little attention has been paid to the potentially nuanced nature of the link between fantasy aggression and actual aggression. In the present article, we examined the influence of four variables in the aggressive fantasy-aggressive behavior link: gender, exposure to violence, fantasy absorption, and level of fantasy about harm befalling loved ones and the self (dysphoric fantasy). Using data from a diverse, community-based sample of 7-14-year olds and their mothers, we replicated the general finding that aggressive fantasy is positively associated with real-world aggressive behavior. However, we also found that the interaction of aggressive fantasy and exposure to violence related significantly to aggression, as did the relation between aggressive fantasy and dysphoric fantasy. When exposure to violence was low, even high levels of aggressive fantasizing did not predict aggressive behavior, and, when aggressive fantasizing was low, even high levels of exposure to violence did not predict aggressive behavior. Similarly, when dysphoric fantasy was high, the connection between fantasy aggression and real aggression was markedly attenuated. The implications of these findings for intervention efforts and future research are considered.

Optimizing Seat Belt and Airbag Designs for Rear Seat Occupant Protection in Frontal Crashes.

Recent field data have shown that the occupant protection in vehicle rear seats failed to keep pace with advances in the front seats likely due to the lack of advanced safety technologies. The objective of this study was to optimize advanced restraint systems for protecting rear seat occupants with a range of body sizes under different frontal crash pulses. Three series of sled tests (baseline tests, advanced restraint trial tests, and final tests), MADYMO model validations against a subset of the sled tests, and design optimizations using the validated models were conducted to investigate rear seat occupant protection with 4 Anthropomorphic Test Devices (ATDs) and 2 crash pulses. The sled tests and computer simulations were conducted with a variety of restraint systems including the baseline rear-seat 3-point belt, 3-point belts with a pre-tensioner, load limiter, dynamic locking tongue, 4-point belts, inflatable belts, Bag in Roof (BiR) concept, and Self Conforming Rear seat Air Bag (SCaRAB) concept. The results of the first two sled series demonstrated that the baseline 3-point belt system are associated with many injury measures exceeding injury assessment reference values (IARVs); showed the significance of crash pulse and occupant size in predicting injury risks; and verified the potential need of advanced restraint features for better protecting the rear-seat occupants. Good correlations between the tests and simulations were achieved through a combination of optimization and manual fine-tuning, as determined by a correlation method. Parametric simulations showed that optimized belt-only designs (3-point belt with pre-tensioner and load limiter) met all of the IARVs under the soft crash pulse but not the severe crash pulse, while the optimized belt and SCaRAB design met all the IARVs under both the soft and severe crash pulses. Two physical prototype restraint systems, namely an "advanced-belt only" design and an "advanced-belt and SCaRAB" design, were then tested in the final sled series. With the soft crash pulse, both advanced restraint systems were able to reduce all the injury measures below the IARVs for all four ATDs. Both advanced restraint systems also effectively reduced almost all the injury measures for all ATDs under the severe crash pulse, except for the THOR. The design with the advanced-belt and SCaRAB generally provided lower injury measures than those using the advanced belt-only design. This study highlighted the potential benefit of using advanced seatbelt and airbag systems for rear-seat occupant protection in frontal crashes.

A simulation study on the efficacy of advanced belt restraints to mitigate the effects of obesity for rear-seat occupant protection in frontal crashes.

OBJECTIVE: Recent field data analyses have shown that the safety advantages of rear seats relative to the front seats have decreased in newer vehicles. Separately, the risks of certain injuries have been found to be higher for obese occupants. The objective of this study is to investigate the effects of advanced belt features on the protection of rear-seat occupants with a range of body mass index (BMI) in frontal crashes. METHODS: Whole-body finite element human models with 4 BMI levels (25, 30, 35, and 40 kg/m2) developed previously were used in this study. A total of 52 frontal crash simulations were conducted, including 4 simulations with a standard rear-seat, 3-point belt and 48 simulations with advanced belt features. The parameters varied in the simulations included BMI, load limit, anchor pretensioner, and lap belt routing relative to the pelvis. The injury measurements analyzed in this study included head and hip excursions, normalized chest deflection, and torso angle (defined as the angle between the hip-shoulder line and the vertical direction). Analyses of covariance were used to test the significance (P <.05) of the results. RESULTS: Higher BMI was associated with greater head and hip excursions and larger normalized chest deflection. Higher belt routing increased the hip excursion and torso angle, which indicates a higher submarining risk, whereas the anchor pretensioner reduced hip excursion and torso angle. Lower load limits decreased the normalized chest deflection but increased the head excursion. Normalized chest deflection had a positive correlation with maximum torso angle. Occupants with higher BMI have to use higher load limits to reach head excursions similar to those in lower BMI occupants. DISCUSSION AND CONCLUSION: The simulation results suggest that optimizing load limiter and adding pretensioner(s) can reduce injury risks associated with obesity, but conflicting effects on head and chest injuries were observed. This study demonstrated the feasibility and importance of using human models to investigate protection for occupants with various BMI levels. A seat belt system capable of adapting to occupant size and body shape will improve protection for obese occupants in rear seats.

Narrow assessments misrepresent development and misguide policy: comment on Steinberg, Cauffman, Woolard, Graham, and Banich (2009).

Intellectual and psychosocial functioning develop along complex learning pathways. Steinberg, Cauffman, Woolard, Graham, and Banich (see record 2009-18110-001) measured these two classes of abilities with narrow, biased assessments that captured only a segment of each pathway and created misleading age patterns based on ceiling and floor effects. It is a simple matter to shift the assessments to produce the opposite pattern, with cognitive abilities appearing to develop well into adulthood and psychosocial abilities appearing to stop developing at age 16. Their measures also lacked a realistic connection to the lived behaviors of adolescents, abstracting too far from messy realities and thus lacking ecological validity and the nuanced portrait that the authors called for. A drastically different approach to assessing development is required that (a) includes the full age-related range of relevant abilities instead of a truncated set and (b) examines the variability and contextual dependence of abilities relevant to the topics of murder and abortion.

Cognitive and emotional differences in young maltreated children: a translational application of dynamic skill theory.

Through a translational approach, dynamic skill theory enhances the understanding of the variation in the behavioral and cognitive presentations of a high-risk population-maltreated children. Two studies illustrate the application of normative developmental constructs from a dynamic skills perspective to samples of young maltreated and nonmaltreated children. Each study examines the emotional and cognitive development of maltreated children with attention to their developing world view or negativity bias and cognitive skills. Across both studies, maltreated children demonstrate negativity bias when compared to their nonmaltreated counterparts. Cognitive complexity demonstrated by the maltreated children is dependent upon a positive or negative context. Positive problem solving is more difficult for maltreated children when compared to their nonmaltreated counterparts. Differences by maltreatment type, severity, timing of the abuse, and identity of the perpetrator are also delineated, and variation in the resulting developmental trajectories in each case is explored. This translation of dynamic skill theory, as applied to maltreated children, enhances our basic understanding of their functioning, clarifies the nature of their developmental differences, and underscores the need for early intervention.

Analyzing development of working models for disrupted attachments: the case of hidden family violence.

This article offers a developmental model of attachment theory rooted in dynamic skill theory. Dynamic skill theory is based on the assumption that people do not have integrated, fundamentally logical minds, but instead develop along naturally fractionated strands of a web. Contrary to traditional interpretations of attachment theory, dynamic skill theory proposes that individuals continue to modify their working models of attachments throughout the lifespan. In particular, working models of close relationships develop systematically through a series of skill levels such that the skills vary across strands in the web and will not automatically form a unified whole. The continual modification of working models is particularly pertinent for the consequences of hidden family violence for individuals' development. Dynamic skill theory shows how trauma can produce not developmental delay or fixation, as has been proposed previously, but instead the construction of advanced, complex working models.