A review of driving risks and impairments associated with attention-deficit/hyperactivity disorder and the effects of stimulant medication on driving performance

INTRODUCTION: Attention-Deficit/Hyperactivity Disorder (ADHD) may interfere with driving competence, predisposing those with the disorder to impaired driving performance and greater risk for adverse driving outcomes. Effective treatment may minimize the risk in those with ADHD. METHOD: We reviewed the scientific literature on driving risks and impairments associated with ADHD and the effects of stimulants on driving performance. Several lines of evidence were considered, including longitudinal studies and community-derived sample studies. The present review is based on a weekly review (by the first author) of all journals in the behavioral and social sciences indexed in the publication Current Contents spanning the past 15 years, as well as a search of the reference section of all studies found that pertained to driving risks associated with ADHD or to the treatment of ADHD as it relates to driving difficulties. RESULTS: The review of the scientific literature demonstrated well-documented driving risks and impairments associated with ADHD and the positive effects of stimulant medications on driving performance. CONCLUSIONS: Clinicians should educate patients/caregivers about the increased risk of adverse outcomes among untreated individuals with ADHD and the role of medication in potentially improving driving performance. IMPACT ON INDUSTRY: Owing to the significantly higher risk of adverse driving outcomes, the use of stimulant medications to treat people with ADHD who drive may reduce such safety risks.     

Comparing spatial conservation prioritization methods with site- versus spatial dependency-based connectivity

Larval dispersal is an important component of marine reserve networks. Two conceptually different approaches to incorporate dispersal connectivity into spatial planning of these networks exist, and it is an open question as to when either is most appropriate. Candidate reserve sites can be selected individually based on local properties of connectivity or on a spatial dependency-based approach of selecting clusters of strongly connected habitat patches. The first acts on individual sites, whereas the second acts on linked pairs of sites. We used a combination of larval dispersal simulations representing different seascapes and case studies of biophysical larval dispersal models in the Coral Triangle region and the province of Southeast Sulawesi, Indonesia, to compare the performance of these 2 methods in the spatial planning software Marxan. We explored the reserve design performance implications of different dispersal distances and patterns based on the equilibrium settlement of larvae in protected and unprotected areas. We further assessed different assumptions about metapopulation contributions from unprotected areas, including the case of 100% depletion and more moderate scenarios. The spatial dependency method was suitable when dispersal was limited, a high proportion of the area of interest was substantially degraded, or the target amount of habitat protected was low. Conversely, when subpopulations were well connected, the 100% depletion was relaxed, or more habitat was protected, protecting individual sites with high scores in metrics of connectivity was a better strategy. Spatial dependency methods generally produced more spatially clustered solutions with more benefits inside than outside reserves compared with site-based methods. Therefore, spatial dependency methods potentially provide better results for ecological persistence objectives over enhancing fisheries objectives, and vice versa. Different spatial prioritization methods of using connectivity are appropriate for different contexts, depending on dispersal characteristics, unprotected area contributions, habitat protection targets, and specific management objectives. Comparación entre los métodos de priorización de la conservación espacial con sitio y la conectividad espacial basada en la dependencia     

Impact of desiccation and heat exposure stress on Salmonella tolerance to acidic conditions

In a recent study, the pH of commonly used Salmonella pre-enrichment media became acidic (pH 4.0 to 5.0) when feed or feed ingredients were incubated for 24 h. Acidic conditions have been reported to injure or kill Salmonella. In this study, cultures of four known feed isolates (S. montevideo, S. senftenberg, S. tennessee, and S. schwarzengrund) and four important processing plant isolates (S. typhimurium, S. enteritidis, S. infantis, and S. heidelberg) were grown on meat and bone meal and later subjected to desiccation and heat exposure to stress the microorganism. The impact of stress on the isolates ability to survive in acidic conditions ranging from pH 4.0 to 7.0 was compared to the non-stressed isolate. Cell injury was determined on xylose lysine tergitol 4 (XLT4) and cell death determined on nutrient agar (NA). When measured by cell death in non-stressed Salmonella, S. typhimurium was the most acid tolerant and S. heidelberg was the most acid sensitive whereas in stressed Salmonella, S. senftenberg was the most acid tolerant and S. tennessee was the most acid sensitive. The pH required to cause cell injury varied among isolates. With some isolates, the pH required for 50% cell death and 50% cell injury was similar. In other isolates, cell injury occurred at a more neutral pH. These findings suggest that the pH of pre-enrichment media may influence the recovery and bias the serotype of Salmonella recovered from feed during pre-enrichment.     

Anaerobic and aerobic transformations affecting stability of dewatered sludge during long-term storage in a lagoon

The goal of this work was to study long-term behavior of anaerobically digested and dewatered sludge (biosolids) in a lagoon under anaerobic and aerobic conditions to determine the stability of the final product as an indicator of its odor potential. Field lagoons were sampled to estimate spatial and temporal variations in the physical-chemical properties and biological stability characteristics such as volatile solids content, accumulated oxygen uptake, and soluble protein content and odorous compound assessment. The analyses of collected data suggest that the surface layer of the lagoon (depth of above 0.15 m) undergoes long-term aerobic oxidation resulting in a higher degree of stabilization in the final product. The subsurface layers (depth 0.15 m below the surface and deeper) are subjected to an anaerobic environment where the conditions favor the initial rapid organic matter degradation within approximately the first year, followed by slow degradation.     

Linking Local Perceptions to the Biophysical and Amenity Contexts of Forest Disturbance in Colorado

Disturbances by insects have considerable effect on the heterogeneity of forested landscapes in North America. Responding to calls for bringing human dimensions of landscape disturbance and heterogeneity into ecological assessments and management strategies, this paper explores linkages between biophysical, socioeconomic, and perceptual aspects of a mountain pine beetle (MPB) (Dendroctonus ponderosae) outbreak in north central Colorado. Findings are presented from surveys conducted with residents of nine Colorado communities and variations in local perceptions of MPB risks and forest management attitudes are compared to indices of tree mortality and amenity characteristics. Findings suggest respondents from lower amenity communities with more recent emphasis on resource extraction and higher tree mortality had significantly higher risk perceptions of some MPB impacts, lower trust in federal forest management, and higher faith in forest industry and specific industry options than those from higher amenity communities with less tree mortality. While not implying these contextual influences fully explain such perceptual dimensions, this paper explores possible implications of heterogeneity across human landscapes for improving the saliency and efficiency of regional forest management and planning.     

Effects of HMX exposure upon metabolic rate of northern bobwhite quail (Colinus virginianus) in ovo

We evaluated the use of the gas exchange rate as an ecologically relevant indicator of chemical stress in avian embryos/eggs. Northern bobwhite quail (Colinus virginianus) were exposed to octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) via feed containing nominal concentrations of 0, 12.5, 50.0, and 125.0 mg kg(-1). Metabolic rates (oxygen consumption) of developing quail eggs were then measured via respirometry to examine potential effects of HMX exposure. Metabolic rates were examined on 5, 9, and 21 d of incubation. Next, concentrations of HMX in embryos/eggs were determined by liquid chromatography-mass spectrometry. Mean (+/-SE) concentrations of HMX in eggs were 21.0+/-5.9, 1113+/-79.0, 3864+/-154.0, and 7426+/-301.1 ng g(-1) in control, low, medium and high dose groups, respectively. There were significant differences in oxygen consumption among the three embryo ages, however differences among the ages were not consistent among dose groups (age x dose group interaction p<0.0001). Oxygen consumption rates did not vary as a function of HMX in embryos (p=0.18). No evidence was observed for alterations of in ovo metabolic rates associated with HMX exposure.     

Diffusion-controlled toluene reference material for VOC emissions testing: International interlaboratory study

The measurement of volatile organic compound (VOC) emissions from building products and materials by manufacturers and testing laboratories, and the use of the test results for labeling programs, continue to expand. One issue that hinders wide acceptance for chamber product testing is the lack of a reference material to validate test chamber performance. To meet this need, the National Institute of Standards and Technology (NIST) and Virginia Tech (VT) have developed a prototype reference material that emits a single VOC similar to the emissions of a diffusion-controlled building product source with a dynamic emissions profile. The prototype material has undergone extensive testing at NIST and a pilot interlaboratory study (ILS) with four laboratories. The next development step is an evaluation of the prototype source in multiple-sized chambers of 14 laboratories in seven countries. Each laboratory was provided duplicate specimens and a test protocol. Study results identified significant issues related to the need to store the source at a subzero Celsius temperature until tested and possible inconsistencies in large chambers. For laboratories using a small chamber and meeting all the test method criteria, the results were very encouraging with relative standard deviations ranging from 5% to 10% across the laboratories.

Implications: Currently, the chamber performance of laboratories conducting product VOC emissions testing is assessed through interlaboratory studies (ILS) using a source with an unknown emission rate. As a result, laboratory proficiency can only be based on the mean and standard deviation of emission rates measured by the participating ILS laboratories. A reference material with a known emission rate has the potential to provide an independent assessment of laboratory performance as well as improve the quality of interlaboratory studies. Several international laboratories with different chamber testing systems demonstrated the ability to measure the emission rate of such a reference material within an acceptable measurement uncertainty.     

Integrated density concentration and surface treatment for selective separation of plastics from a mixture

Journal of Material Cycles and Waste Management - Froth flotation and elutriation were found to be effective in separating individual plastics from a plastic mixture by exploiting differential...     

Temporal dynamics and plasticity in the cellular immune response of the sea fan coral, Gorgonia ventalina

The temporal dynamics of the invertebrate immune response often determines an organism’s success in responding to physiological stress, physical damage, and pathogens. To date, most immune challenge studies have been conducted under highly controlled laboratory conditions, with few attempts to study immune function in the wild. In this study, we characterized the temporal dynamics of the Caribbean sea fan, Gorgonia ventalina, cellular immune response [granular amoebocyte aggregation and prophenoloxidase (PPO) activation] to allogenic grafts in the laboratory and field using a clonally replicated design. Amoebocyte reaction time differed markedly between the lab (% amoebocyte surface area in tissue sections peaked at 2 days) and field (peak at 6 days). PPO activity decreased between 0 and 6 days after grafting in both ungrafted and grafted tissue, suggesting PPO is decoupled from other cellular components. The reaction norms of the fold induction in % amoebocyte area between disease-grafted and healthy-grafted tissue of each colony across time indicate high intercolony plasticity in cellular immune response. The plasticity between colonies was also evident in the magnitude of cellular immune response, ranging from a 0.88- to 1.60-fold increase in amoebocyte area between initial and 6 days for the disease-grafted tissue. With the demonstration of highly dynamic cnidarian cellular immune responses, our study expands understanding of the evolutionary ecology of metazoan immune defense mechanisms.