Prenatal exclusion of stickler syndrome

Stickler syndrome is an autosomal dominant disorder of the connective tissue which includes ocular and systemic manifestations. We report on a large kindred in which we were able to demonstrate very tight linkage between the disease and the type II collagen gene (COL2A1) (LOD score 3·91 at θ=0). In a family in which the father and one of his daughters were severely affected, DNA analysis from a chorionic villus sample demonstrated that the fetus possessed the normal allele of COL2A1. Thereafter a normal child was born.     

The APCA Exhibition

On June 5 and 6 of 1980, two parallel plume oxidation studies were carried out in the vicinity of the Tennessee Valley Authority's Colbert Steam Plant. One study was performed in a smog chamber into which stack gases were injected and mixed with ambient air. The other study included direct airborne sampling of the power plant plume. Atmospheric oxidation rates for the conversion of SO₂ to SO₄ ^2- and the removal rates of NO _x (which is presumably the rate of NO₃ ^- formation) were estimated for both studies. The SO₂ to SO₄ ^2- rate coefficients were found to be 0.022 ± 0.009 h^-1 for both chamber experiments and the first airborne sampling day. For the second day, a rate constant of 0.041 ± 0.052 h^-1 was estimated from the aircraft data. The large deviation in this value is explained by the fact that the plume from the power plant combined and reacted with the urban plume from the city of Florence, AL. The formation of a very large "O3 bulge" on this day is also attributed to the mixed plumes. The first order rate coefficients for NO _x removal were estimated to be 0.27 ± 0.14 h^-1 for both chamber experiments and the first airborne sampling day. A NO _x removal rate could not be determined for the second airborne sampling day.     

Testing safety commitment in organizations through interpretations of safety artifacts

Problem

Safety culture relates to injuries and safety incidents in organizations, but is difficult to asses and measure. We describe a preliminary test of assessing an organization's safety culture by examining employee interpretations of organizational safety artifacts (safety signs).

Method

We collected data in three organizations using a new safety culture assessment tool that we label the Safety Artifact Interpretation (SAI) scale; we then crossed these data with safety climate and leadership evaluations.

Results

SAI were interpreted by employees in accordance with two conceptually distinct themes that are salient in the literature on organizational safety culture: safety compliance and commitment to safety. A significant correlation exists between SAI scores and the organizational safety climate. A similar (though insignificant) relationship was observed between SAI scores and leadership ratings.

Impact on industry

Employee perceptions and interpretations of safety artifacts can facilitate assessments of safety culture and can ultimately lead to understanding of and improvements in the level of organizational safety.     

The use of supervisory practices as leverage to improve safety behavior: a cross-level intervention model

Introduction: The paper presents three intervention studies designed to modify supervisory monitoring and rewarding of subordinates' safety performance. Method: Line supervisors received weekly feedback concerning the frequency of their safety-oriented interactions with subordinates, and used this to self-monitor progress toward designated improvement goals. Managers higher up in the organizational hierarchy received the same information, coupled with synchronous data concerning the frequency of workers' safety behaviors, and highlighting co-variation of supervisory action and workers' behavior. Results: In all the companies involved, supervisory safety-oriented interaction increased significantly, resulting in significant changes in workers' safety behavior and safety climate scores. Continued improvement during the post-intervention period suggests the inclusion of workers' safety behavior as in-role supervisory responsibility. Applied and theoretical implications are discussed.     

Comparison of air quality data obtained from roof top,sidewalk and suburban areas

A comparison of air quality data obtained at a downtown roof top location, a surburban area, a main road curbside and adjacent to a major highway was conducted. The results of this study revealed that a reasonably good correlation between daily average concentrations at these locations can be established. For primary pollutants it was found that within the immediate release zone their average concentration is 3.5 to 4.0 times higher than at a close location but at roof top level. Total suspended particulate (TSP) concentration was found to increase by about 80%, and O₃ is reduced by about 25%. No significant difference was obtained between daily averages obtained at the city center location and the suburb site 5 km away.     

Learning disability and leadership: Becoming an effective leader

This study investigates learning disability (LD) as an individual‐differences variable predicting leadership emergence, role occupancy, and effectiveness. We hypothesize that individuals with LD are less likely to occupy leadership roles, and that informal group processes (leadership emergence) will mediate the relationship between LD and leadership role occupancy. We also hypothesized that, among leaders promoted and selected for leadership training, there would be a negative relationship between LD and effective leadership. We first checked for LD in a sample of 1076 soldiers, measuring cognitive ability with a geometric‐analogies test as a control. Some months later, during the soldiers' basic training, we measured leadership emergence. We then identified those who were selected for leadership training, recording, and measuring their effectiveness according to supervisory and peer evaluations. Leadership emergence was found to mediate the negative relationship between LD and leadership role occupancy. There were no significant differences among leaders (n = 308) with and without LD in regard to leadership effectiveness. Copyright © 2013 John Wiley & Sons, Ltd.     

Colloid transport in a geochemically heterogeneous porous medium: aquifer tank experiment and modeling

To examine colloid transport in geochemically heterogeneous porous media at a scale comparable to field experiments, we monitored the migration of silica-coated zirconia colloids in a two-dimensional layered porous media containing sand coated to three different extents by ferric oxyhydroxides. Transport of the colloids was measured over 1.65 m and 95 days. Colloid transport was modeled by an advection-dispersion-deposition equation incorporating geochemical heterogeneity and colloid deposition dynamics (blocking). Geochemical heterogeneity was represented as favorable (ferric oxyhydroxide-coated) and unfavorable (uncoated sand) deposition surface areas. Blocking was modeled as random sequential adsorption (RSA). Release of deposited colloids was negligible. The time to colloid breakthrough after the onset of blocking increased with increasing ferric oxyhydroxide-coated surface area. As the ferric oxyhydroxide surface area increased, the concentration of colloids in the breakthrough decreased. Model-fits to the experimental data were made by inverse solutions to determine the fraction of surface area favorable for deposition and the deposition rate coefficients for the favorable (ferric oxyhydroxide-coated) and unfavorable sites. The favorable deposition rate coefficient was also calculated by colloid filtration theory. The model described the time to colloid breakthrough and the blocking effect reasonably well and estimated the favorable surface area fraction very well for the two layers with more than 1% ferric oxyhydroxide coating. If mica edges in the uncoated sand were considered as favorable surface area in addition to the ferric oxyhydroxide coatings, the model predicted the favorable surface area fraction accurately for the layer with less than 1% ferric oxyhydroxide coating.     

The effect of workers' visibility on effectiveness of intervention programs: supervisory-based safety interventions

INTRODUCTION: This paper discusses an organizational change intervention program targeting safety behaviors and addresses important considerations concerning the planning of organizational change. Using layout of the plant as a proxy for ease of daily leader-member interaction, the effect of workers' visibility on the effectiveness of supervisory-based safety (SBS) interventions is examined. Through a reinforcement-learning framework, it is suggested that visibility can affect supervisors' incentive to interact with subordinates regarding safety-related issues. METHOD: Data were collected during SBS intervention studies in five manufacturing companies. RESULTS: Results suggest a reinforcement cycle model whereby increased visibility generates more frequent exchanges between supervisors and employees, resulting in improved safety behavior among employees. In turn, employees' safer behavior reinforces continued supervisory safety-related interaction. CONCLUSION AND IMPACT ON INDUSTRY: Visibility is an important moderator in supervisory based safety interventions, and can serve to increase workplace safety. Implications of these findings for safety are discussed.     

Resources and coping with stressful events

This longitudinal, quasi‐field experiment tested whether perceived stress and increase in perceived stress are related to the resources of the individual, namely, personality (core self evaluation scale (CSES)), physical fitness, social support (acceptance and/or rejection by peers), and cognitive abilities. Perceived stress scale (PSS) was administered at two points in time to participants in a two‐day selection process for a military unit, whose stressful environment formed the manipulation in this study. Baseline PSS was obtained from soldiers before the selection activity, when threatened with resource loss. PSS was next administered during the selection activity, when individuals had to cope with actual loss of resources and difficulty in regaining them. As expected, participants perceived more stress during the selection activity. Participants with higher CSES, higher cognitive abilities and higher levels of social support perceived lower stress levels prior to the activity. The increase in stress level was lower for participants with better fitness levels, but greater for participants rejected by their peers. Exploratory analysis of resource overlap was conducted and revealed a contribution of few key resources to coping, even in the presence of other resources. Copyright © 2008 John Wiley & Sons, Ltd.