Mild head injury in children and adolescents: A review of studies (1970–1995).

In this article, the authors provide a comprehensive review of the research of mild head injury in children and adolescents from 1970 to 1995. Because of marked variability in methodologies across studies, a preliminary box-score tally was computed, without regard to studies' scientific or methodological merit. These results revealed 13 adverse, 18 null, and 9 indeterminate findings related to neuropsychological, academic, or psychosocial outcome. When studies were classified based on methodological merit, the stronger studies were generally associated with null outcomes across domains. However, a few of the less stronger neuropsychological studies (5 of 40) reported subthreshold and transitory alterations during the early postinjury period. At the present time, cautious acceptance of the null hypothesis is recommended until more definitive studies are conducted that address the problems raised in this review. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adaptation of community relocation: The interactive influence of psychological resources and contextual factors.

This longitudinal study examined the interactive influences of psychological resources and contextual factors on short-term adaptation to community relocation in a sample of older women (N?=?102, mean age?=?71.6). The effects of three psychological resources ( environmental mastery, autonomy, and personal growth) and three contextual factors (pressure to move, difficulty of the move, and unexpected gains experienced ) on emotional reactions to relocation were examined. The pattern of findings suggests that women with greater psychological resources were more resilient in the face of negative circumstances but that the emotional "boost" of unexpected gains was greatest for women with lower premove resources. These results underscore the importance of considering event-relevant psychological resources and contextual factors and including both negative and positive aspects of the adaptational process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The 1996 North American Interagency Intercomparison of Ultraviolet Monitoring Spectroradiometers

Concern over stratospheric ozone depletion has prompted several government agencies in North America to establish networks of spectroradiometers for monitoring solar ultraviolet irradiance at the surface of the Earth. To assess the ability of spectroradiometers to accurately measure solar ultraviolet irradiance, and to compare the results between instruments of different monitoring networks, the third North American Interagency Intercomparison of Ultraviolet Monitoring Spectroradiometers was held June 17–25, 1996 at Table Mountain outside Boulder, Colorado, USA. This Intercomparison was coordinated by the National Institute of Standards and Technology (NIST) and the National Oceanic and Atmospheric Administration (NOAA). Participating agencies were the Environmental Protection Agency; the National Science Foundation; the Smithsonian Environmental Research Center; the Department of Agriculture; and the Atmospheric Environment Service, Canada. The spectral irradiances of participants’ calibrated standard lamps were measured at NIST prior to the Intercomparison. The spectral irradiance scales used by the participants agreed with the NIST scale within the combined uncertainties, and for all lamps the spectral irradiance in the horizontal position was lower than that in the vertical position. Instruments were characterized for wavelength uncertainty, bandwidth, stray-light rejection, and spectral irradiance responsivity, the latter with NIST standard lamps operating in specially designed field calibration units. The spectral irradiance responsivity demonstrated instabilities for some instruments. Synchronized spectral scans of the solar irradiance were performed over several days. Using the spectral irradiance responsivities determined with the NIST standard lamps, the measured solar irradiances had some unexplained systematic differences between instruments.     

Bridges 2002: Mathematical Connections in Art,Music, and Science

Nexus Network Journal - .     

Glutamate receptor-mediated restoration of experience-dependent place field expansion plasticity in aged rats.

Place fields of hippocampal pyramidal cells expand asymmetrically when adult rats repeatedly follow the same route. This behaviorally induced expression of neuronal plasticity uses an NMDAR-dependent, LTP-like mechanism and could be used by hippocampal networks to store information. Aged spatial memory-impaired rats exhibit defective experience-dependent place field expansion plasticity. One possible explanation for this aged-associated deficit is alterations in glutamatergic function. In fact, both NMDAR- and AMPAR-mediated field excitatory postsynaptic potentials in CA1 decrease with aging. The current study investigated whether modulation of either AMPA or NDMA receptor activity could restore this experience-dependent plasticity by prolonging AMPAR activity with the ampakine CX516 and modulating the NMDAR with the noncompetitive antagonist memantine. The spatial firing characteristics of multiple CA1 pyramidal cells were monitored under both treatment conditions as aged rats repeatedly traversed a circular track. Compared to the saline baseline condition, acute administration of memantine, but not CX516, reinstated experience-dependent place field expansion. Taken together, these data suggest that pharmacological manipulation of the NMDAR can improve the function of hippocampal networks critical to optimal cognition in aging. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interfacial Chemistry of an Aluminum-to-EPDM Rubber Bonding System

During recent assessment of aging in aluminum-to-rubber bonds on stored solid rocket motors, corrosion and minor insulator debonds were observed. A test was conducted to study the progressive effect of exposure to high humidity on the bondline; elevated temperature was used to accelerate the aging. In a parallel test, samples were held at elevated temperature in a dry atmosphere. The test results were compared with the analyses of corroded and noncorroded hardware samples. The predominant corrosion product detected at the bondlines was aluminum oxide/hydroxide. In general, there was a very good correlation between the Cl:Al atomic percent ratio calculated from X-ray photoelectron spectroscopy analysis of the ruptured bondline surfaces and the visual characterization of the extent of corrosion. The Cl:Al ratio, which represented the ratio of primer to corrosion product at the locus of failure, varied from 0.4 to 47. The implications for metal-to-rubber bond fabrication and storage are discussed.     

The use of prototypes to bridge knowledge boundaries in agile software development

Bridging knowledge boundaries among project team members is essential to prevent delays or complete failure of software development projects. Prior researchers have reported that software prototypes can be used to help bridge knowledge boundaries between team members in traditional software development settings, yet their use in an agile development setting remains unexplored. Agile development centers the interactions between team members on emerging representations of the prototype whose properties are prone to change over time. Therefore, we conducted an in‐depth study of an agile development project to enhance our understanding on how software prototypes are used as boundary objects in a distributed team setting. Our analyses of team member interactions during 46 virtual meetings that took place over a period of 6 months revealed four different prototype use practices (exemplifying, contrasting, relating, framing) that were effective in bridging syntactic, semantic, or pragmatic knowledge boundaries. We also provide empirically grounded evidence of how variations in object properties can afford different use practices, how the use practices take advantage of these properties, and how object properties are reshaped through these use practices as different types of knowledge boundaries are bridged. These findings bear important implications for research on prototypes as boundary objects in software development in particular and boundary object use in general.     

A review of the influence of humidity on photocatalytic decomposition of gaseous pollutants on TiO2-based catalysts

Humidity can have an appreciable influence on the photocatalytic degradation of volatile organic compounds (VOCs) in air. It has been proposed that there are multiple layers of water molecules on the surface of the photocatalyst, and a VOC molecule must penetrate this layer and be able to diffuse to the photocatalytic surface for a reaction to occur. An updated analysis of related literature from the past 12 years indicates that this proposed mechanism remains reasonable for explaining observed effects. According to this mechanism the VOC's hydrophilicity should dominate the influence of humidity on the photocatalytic reaction kinetics, and this effect can be seen in a categorization of literature observations based on the octanol-water partition coefficient. The frequently cited Langmuir-Hinshelwood kinetic model does not directly account for humidity effects in this way but can be adapted for this purpose. As an example, the rate of photocatalytic decomposition of chlorobenzene in air under humid conditions can be described by a modified Langmuir-Hinshelwood kinetic model, where the reaction rate coefficient is dependent on the water concentration. Understanding and considering the effect of humidity is useful for optimizing the efficacy of photocatalytic VOC treatment of air.