OMVPE growth of P-type GaN using solution Cp2Mg

Bis(cyclopentadienyl)magnesium (Cp₂Mg) is a common source for p-type doping in GaN and AlInGaP materials. It is a white crystalline solid with very low vapor pressure, leading to transport problems similar to solid trimethyindium (TMI). Some of these problems can be alleviated by a newly developed source-solution magnesocene, Cp₂Mg, dissolved in a solvent that is essentially nonvolatile. In this paper, we report the growth and comparative results of Mg-doped GaN grown by OMVPE using solid and solution Cp₂Mg. Using both sources, we optimized parameters to obtain high-quality GaN growth with hole concentrations up to 1 10¹⁸/cm³.     

Toward a conceptualization of the family's adaptation to a member's head injury: A critique of developmental stage models.

Developmental stage models proposed to conceptualize the family's adaptation to a head-injured member are critiqued. In general, hypotheses about stages have not been subjected to empirical investigation. Due to conceptual problems in the models, the stages do not meet the criteria of legitimate explanatory constructs. In their present form, stages proposed by different models are, at best, of heuristic value. It is argued that principles from S. Minuchin's (1974) structural family therapy model may be integrated with the stage model approach in a manner that helps resolve some conceptual problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Highly Stable Plasmon Induced Hot Hole Transfer into Silicon via a SrTiO3 Passivation Interface

Extracting plasmon‐induced hot carriers over a metal–semiconductor Schottky barrier enables photodetection below the semiconductor bandgap energy. However, interfacial carrier recombination hinders the efficiency and stability of this process, severely limiting its implementation in telecommunication. This study proposes and demonstrates the use of epitaxially grown lattice‐matched SrTiO₃ for interfacial passivation of silicon‐based plasmonic Schottky devices. The devices are activated by an electrical soft‐breakdown of the interfacial SrTiO₃ layer, resulting in reproducible rectified Schottky characteristics. The transition to a low resistance state of the SrTiO₃ layer boosts the extraction efficiency of hot holes upon resonant plasmonic excitation, giving rise to a two orders of magnitude higher photocurrent compared to devices with a native oxide layer. Photoresponse, tunability, and barrier height studies under reverse biases as high as 100 V present superior stability with the incorporation of the SrTiO₃ layer. The investigation paves the way toward plasmon‐induced photodetection for practical applications including those under challenging operating conditions.     

Prospective intervention opportunities regarding device ownership and the reduction of damage to handheld ruggedized devices with shift workers

Industrial equipment such as ruggedized handheld computers, scanners, and label printers used within asset tracking environments are expensive to purchase and costly to repair. For organizations that use this equipment, there is value in understanding when and why damage occurs and how much of those costs are potentially associated with the employees’ own sense of psychological ownership and organizational pride. Given the connection between psychological ownership and pride, the purpose of this study was to analyze employee surveys to determine what methods, tools, or programs could reduce repair and replacement while developing a stronger sense of ownership for ruggedized devices used in material‐handling industries by shift workers. Unstructured interviews about device repair with management from a large industrial company were utilized to create a multiple‐choice, anonymous online survey (n = 353). Of the six interventions proposed, assigning the same device to the same employee every shift appeared to have the most consistent and positive response. Destruction rates and costs should be posted for employee viewing and managers of workgroups with consistently high destruction rates should receive additional training. An incentive‐based program for employees responsible for the least amount of device damage as well as an individual‐assignment of devices to employees may be considered. Applications for this student include providing a tool with which organizations can use to gauge employee ownership of equipment as well as to identify interventions that may aid in mitigating expenses associated with industrially rugged equipment.     

Investigating the Impact of Task Change Type and Transparency on Transfer of Learning

This article investigates users' transfer of learning on two e-mail platforms with different transparency levels and task change types. The objective is to provide implication on task design in product upgrading. A mixed design of 4 (types of task change)?×?2 (transparency)?×?2 blocks (Hotmail and Outlook platform) within-subjects design and 3 levels of expertise between-subjects design, both having repeated measures on type of task change and transparency, was used to evaluate participants' transfer of learning. A main effect of both transparency and task change type is expected. High-transparency tasks are expected to lead to higher performance than low-transparency tasks. Commission task changes are expected to lead to lower performance than other types of task change due to the addition of new task steps. The results showed that commission task changes led to the greatest disturbance on user performance, whereas performance is best during sequence task changes in which participants have a positive transfer in performance time per step and no increase in error ratio. Participants also showed better transfer of learning in high-transparency tasks. The conclusion is that transparency level is critical in the future design of product changes. A refined design approach is necessary to ensure that the design tasks are highly transparent to users. In addition, to facilitate user's transfer of learning, commission task changes should be reduced and sequence task changes should be increased.     

Interventions to maintain mobility: What works?

Mobility, in broad terms, includes everything from the ability to move within your immediate environment (e.g., get out of bed) to the ability to drive across the country. Mobility is essential to maintaining independence and wellbeing, particularly for older adults. This is highlighted by the large number of interventions developed for older adults with the goal of maintaining such mobility. The current paper reviews the state of the science with respect to mobility interventions. Inclusion criteria for the review were: (1) articles must have been peer-reviewed; (2) interventions were evaluated in a randomized controlled trial (RCT); (3) studies included a mobility outcome such as lifespace, driving, or walking ability; (4) studies included a sample of healthy community-dwelling older adults (e.g., not investigations of disease conditions); and (5) studies must have reported enough empirical data and detail such that results could potentially be replicated. Three main types of interventions were identified: cognitive training, educational interventions, and exercise interventions. A detailed summary and evaluation of each type of intervention, and the current evidence regarding its effectiveness in maintaining mobility, are discussed. Several interventions show clear evidence of effectiveness, and thus are prime areas for translation of results to the older population. Needs and issues for future intervention research are also detailed.