Impact of consistent boundary layer mixing approaches between NAM and CMAQ

Discrepancies in grid structure, dynamics and physics packages in the offline coupled NWS/NCEP NAM meteorological model with the U.S. Environmental Protection Agency Community Multiscale Air Quality (CMAQ) model can give rise to inconsistencies. This study investigates the use of three vertical mixing schemes to drive chemistry tracers in the National Air Quality Forecast Capability (NAQFC). The three schemes evaluated in this study represent various degrees of coupling to improve the commonality in turbulence parameterization between the meteorological and chemistry models. The methods tested include: (1) using NAM predicted TKE-based planetary boundary height, h, as the prime parameter to derive CMAQ vertical diffusivity; (2) using the NAM mixed layer depth to determine h and then proceeding as in (1); and (3) using NAM predicted vertical diffusivity directly to parameterize turbulence mixing within CMAQ. A two week period with elevated surface O₃ concentrations during the summer 2006 has been selected to test these schemes in a sensitivity study. The study results are verified and evaluated using the EPA AIRNow monitoring network and other ozonesonde data. The third method is preferred a priori as it represents the tightest coupling option studied in this work for turbulent mixing processes between the meteorological and air quality models. It was found to accurately reproduce the upper bounds of turbulent mixing and provide the best agreement between predicted h and ozonesonde observed relative humidity profile inferred h for sites investigated in this study. However, this did not translate into the best agreement in surface O₃ concentrations. Overall verification results during the test period of two weeks in August 2006, did not show superiority of this method over the other 2 methods in all regions of the continental U.S. Further efforts in model improvement for the parameterizations of turbulent mixing and other surface O₃ forecast related processes are warranted.     

Transformational leadership,psychological empowerment,and the moderating role of mechanistic–organic contexts

The current study examines the empowering effects of transformational leaders and the extent to which these effects differ across mechanistic–organic organizational contexts. Psychological empowerment is hypothesized to provide a comprehensive motivational mechanism explaining the relationships between transformational leadership and employee job‐related behaviors. In addition, the relationships between transformational leadership, employee psychological empowerment, and job‐related behaviors are hypothesized to be stronger in organizations with more organic as opposed to mechanistic structures. Results based on a cross‐organizational sample of employees and their immediate supervisors provide support for the hypothesized relationships. Psychological empowerment mediated relationships between transformational leadership and employee task performance and organizational citizenship behaviors. The mediating role of psychological empowerment was then found to be conditional upon mechanistic–organic contexts. More specifically, organic structures enhanced, whereas mechanistic structures constrained, the empowering influence of transformational leaders. In highly mechanistic contexts, the indirect effects were no longer statistically significant. Implications for theory, research, and organizational management are discussed. Copyright © 2013 John Wiley & Sons, Ltd.     

Applying DPSIR to sustainable development

The DPSIR framework was devised in the late 1990s as a tool for the reporting and analysis of environmental problems, ranging in scale from global systems to localized watersheds. Since then, international organizations have begun to apply this framework to the evaluation of sustainable development initiatives, to better understand and overcome barriers to sustainability. While this may seem a logical application for an integrated environmental assessment tool, the use of DPSIR in sustainable development will likely perpetuate the least satisfactory outcomes of development. DPSIR cannot address the impact of aggregated, informal responses on the drivers and pressures related to environmental problems and sustainability challenges. This problem is not merely an oversight of the framework, but an issue that emerges within the structure of DPSIR itself through the unexamined, unacknowledged hierarchy of actors that this framework implicitly creates with its typology. Therefore, a DPSIR-centered approach is not a new direction for development within international organizations, but instead, a reproduction of existing inequalities between actors and stakeholders within current approaches.     

Prenatal diagnosis of congenital non-bullous ichthyosiform erythroderma (lamellar ichthyosis)

We report the first positive prenatal diagnosis ofcongenital non-bullous ichthyosiform erythroderma or lamellar ichthyosis. Fetal skin samples were obtained by fetoscopy at 21 weeks' gestation and examined by light and electron microscopy. Light microscopy revealed a thickened interfollicular epidermis with multiple layers of flattened cells and excessive keratinization of the epidermal lining of the follicular infundibulum. Electron microscopy of the thickened epidermis revealed granular cells that contained larger-than-normal keratohyalin granules and multiple layers of parakeratotic cornified cells. Although there was regional variation in the degree of interfollicular keratinization, follicles from all regions showed greater and more complete keratinization, indicating that they express the abnormality early enough in development to permit prenatal diagnosis at about 20 weeks' gestation.     

Assessing potential risks to wildlife and sportsmen from exposure to dioxin in pulp and paper mill sludge spread on managed woodlands

Potential human and wildlife exposures to TCDD in landspread pulp and paper mill sludge in the State of Maine were evaluated by means of a human health and an ecological risk assessment methodology. The highest historical concentrations of TCDD reported for these sludges do not present a risk to American woodcock, selected as an indicator species for this analysis. Concentrations of TCDD as high as 50 ppt in soil are not likely to produce adverse effects in the embryonic/hatchling stage of the woodcock. This soil concentration of TCDD does not present a significant risk to sportsmen and their families that may consume birds which inhabit these sites.     

Colloidal phosphorus in surface runoff and water extracts from semiarid soils of the western United States

Colloidal particles in runoff may have an important role in P transfer from soils to waterbodies, but remain poorly understood. We investigated colloidal molybdate-reactive phosphorus (MRP) in surface runoff and water extracts of calcareous arable soils from the semiarid western United States. Colloidal MRP was determined by ultrafiltration and operationally defined as MRP associated with particles between 1 microm and 1 nm diameter, although a smaller pore-size filter (0.3 nm) was used to define the lower size limit of colloids in water extracts. In surface runoff from three calcareous soils generated by simulated sprinkler irrigation, colloidal MRP concentrations ranged between 0.16 and 3.07 microM, constituting between 11 and 56% of the MRP in the <1-microm fraction. Concentrations were strongly correlated with agronomic and environmental soil-test P concentrations for individual soils. Water extracts of a range of similar soils contained two size fractions of colloidal MRP: a larger fraction (1.0-0.2 microm) probably associated with fine clays, and a smaller fraction (3-0.3 nm) probably associated with Ca-phosphate minerals. Colloidal MRP was solubilized in the acidic medium of the colorimetric detection procedure, suggesting that a fraction of the filterable MRP in runoff from calcareous soils may not be as readily bioavailable as free phosphate in waterbodies. Our results suggest that colloidal MRP is an important but poorly understood component of P transfer in runoff from calcareous western U.S. soils and should be given greater consideration in mechanistic studies of the P transfer process.     

Preliminary evidence of the role of hydrogen peroxide in the degradation of benzo[a]pyrene by a non-white rot fungus Fusarium solani

In order to study the enzymatic mechanisms involved in the successive steps of BaP degradation by a Deuteromycete fungus Fusarium solani, we developed an indirect approach by using inhibitors of enzymes. We used either specific inhibitors of peroxidases (i.e. salicylhydroxamic acid) and of cytochrome P-450 (i.e. piperonyl butoxyde) or inhibitors of both enzymes (i.e. potassium cyanide). Surprisingly, no expected decrease of BaP degradation was observed with most inhibitors tested. On the contrary, more BaP was degraded. Only butylated hydroxytoluene, which acts as a free radical scavenger, inhibited BaP degradation. The inhibition of these enzymes, which use H(2)O(2) as a cosubstrate, might have resulted in an increase of hydrogen peroxide availability in the fungal cultures. This enhancement could induce formation of reactive oxygen species (ROS) which might be the agents that initiate benzo[a]pyrene oxidation. This study proposed a hypothetic alternative metabolic pathway involved in PAH metabolism by Fusarium solani.     

Driving while impaired (DWI) by alcohol convictions among alcohol, cocaine, and cannabis clients in treatment

OBJECTIVE: Although studies have demonstrated that clients in treatment for alcohol abuse are more at risk of driving while impaired (DWI) by alcohol than normal licensed drivers from the general population, no research was found on DWI convictions among those in treatment for abusing cannabis or cocaine. The purpose of this article is to compare DWI convictions among clients in treatment for alcohol, cannabis, cocaine, or various combinations of these substances, compared to a matched population control group. METHOD: A stratified random sample of driver records was drawn from seven client groups who sought treatment in 1994 for alcohol, cannabis, cocaine, or any combination of these substances (n = 445). A random sample of drivers, frequency matched by age and sex (n = 566), served as control subjects. RESULTS: Logistic regression analysis, controlling for sex and age, was conducted to assess whether DWI convictions were elevated for each of the client groups, compared to controls. Two sets of analyses were conducted, before treatment (from 1985 to 1993) and after treatment (from 1995 to 2000). In the time period before treatment, every drug group except the "cannabis only" group had significantly more DWI convictions than controls (p < .05). In the period after treatment, the "alcohol only," "cocaine only," "alcohol and cocaine," and the "cocaine and cannabis" groups still had significantly more DWI convictions than controls (p < .05). CONCLUSION: The results show that DWI convictions are elevated among those who abused cocaine but not among those who abused cannabis. The results suggest that cross-addiction of alcohol and cocaine is common, and problematic drinking among cocaine clients can go undetected when clients are being diagnosed for treatment.     

License extensions for clean-record drivers: A 4-year follow-up

Over 4,000,000 of California's 17,000,000 licensed drivers used to come to the California Department of Motor Vehicles (DMV) annually to take written and vision tests in order to renew their driver licenses. In an effort to increase public convenience and reduce costs, extension of the license by mail was implemented for selected groups of drivers with clean records over the life of their previous licenses. Continued implementation of the program was subject to evaluation of its effect on traffic safety. Since clean-record drivers make up about 50% of the renewal population, this program made it possible for some 2,000,000 drivers annually to avoid coming to the DMV for license renewal. Two studies of program safety effects were conducted, one evaluating a 2-year extension (760,000 subjects), and the other a 4-year extension (407,000 subjects). Random assignment to a group offered extension by mail or to a control group undergoing standard renewal testing and procedures was followed by careful tracking of accident and conviction activity. During the 48-month period following mailing of renewal notices or extension offers, the extension group had a slightly higher accident rate than did the in-person renewal group — an increase of 1%, or 13 accidents for every 10,000 extension offers. Although this small increase in accident rate would translate into about 2,500 additional accident involvements per year if applied to the current volume of clean-record drivers eligible for extension, statistical tests of significance indicated that the increase could easily be due to sampling error (p>.10). A supplemental Bayesian analysis resulted in a .24 probability that there was no true increase. The administrative cost savings attributable to the extension program were conservatively estimated to be $3,000,000 per year.