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891.
Fatal accident data from 50 states and the District of Columbia were examined in order to determine the relationship between alcohol availability and fatal motor vehicle accidents. This relationship was analyzed for both fatal accidents and motor vehicle fatalities (potentially more than one per accident) using multiple regression. The independent variables were: (1) driving age (percent of drivers under 21); (2) beverage purchase age; (3) average beer consumption; (4) number of outlets per million population selling alcohol for on-premise consumption; (5) percentage of metropolitan residents; (6) percentage of male drivers; and (7) mileage per driver per year. It was found that the regression analyses for fatal accidents and for fatalities were highly similar. Driving age was the strongest predictor of highway mortality. On-premise availability of alcohol was significantly and inversely associated with motor vehicle fatalities. This suggests that when on-premise outlets are fewer and more geographically spread out, the chances of drinking and driving are greater. Finally, average beer consumption was significantly and positively associated with highway fatalities perhaps because many drivers consider it a “soft” alcoholic beverage that will not impair their ability to drive.  相似文献   
892.
Problems arising from application of the representative criterion for conservation and natural heritage evaluation are discussed. An ecological basis to this criterion is suggested that focuses on those key environmental factors dominating biotic response. A methodology is proposed that utilizes computer-based methods of establishing and interrogating spatial data bases (geographic information systems), environmental modeling, and numeric analysis. An example is presented illustrating some of the advantages and limitations of classification and dimension reduction techniques in both defining bioenvironments and displaying their spatial distribution. The advantages of this method for representativeness evaluation are that it maximizes the utility of available data, is explicit and repeatable, and enables large areas to be analyzed at relatively fine scales.  相似文献   
893.
Objective: Drunk driving is one of the major behavioral issues connected with problematic alcohol consumption. The objective of this study was to evaluate the relationship between personality traits and social problem-solving skills of individuals who drive while intoxicated.

Method: One hundred forty-four individuals apprehended twice while driving drunk and sent to a driver behavior training program (9 females and 135 males) participated in our study. The Eysenck Personality Questionnaire Revised–Abbreviated (EPQ-RA) composed of 4 subscales (Extroversion, Neuroticism, Psychoticism, and Lying) and the Social Problem Solving Inventory (SPSI) composed of 7 subscales (Cognitive, Emotion, Behavior, Problem Definition and Formulation, Creating Solution Options, Solution Implementation and Verification, and Decision Making) were used to evaluate the participants.

Results: A positive relationship was found between the Extroversion subscale of the EPQ-RA and the Cognition subscale (P <.01), Emotion subscale (P <.01), Behavior subscale (P <.01), Generation of Alternatives subscale (P <.01), Decision Making subscale (P <.05), and Solution Implementation and Verification subscale (P <.01). For individuals who repeated intoxicated driving, all subscales of the EPQ-RA (Extroversion, Lying, Neuroticism, and Psychoticism subscales) explained 12% of the scores of the Cognition subscale and 16.2% (P <.001) of the Emotion subscale of the SPSI. There was no significant relationship between the first and second incident alcohol blood levels (P >.05).

Conclusion: Drinking and driving behaviors appear to be negative or maladaptive behaviors closely related to personality traits and may represent an effort to avoid negative emotions. Evaluation of negative emotions may have an important place in training programs intended to change drunk driving behavior.  相似文献   

894.
This paper highlights the value of systems theory and its application to human and organizational factors (HOF). HOF specialists consider multiple systems characteristics in their analyses but are often unaware of the relevant theory applied in their analysis. We argue that a structured effort to take key systems characteristics into account in HOF practice would increase the depth and breadth of safety management analyses and help HOF specialists to act more effectively on industrial socio-technical systems. First, the paper identifies the following seven system theory characteristics: constitution, multi-axis representation, limit, emergence, variety, coherence, and causal interaction, which are then illustrated with examples from the HOF field. Finally, we discuss the two main benefits of integrating system thinking in a HOF approach to safety management: (1) an improved understanding of the inner workings of an industrial socio-technical system; and (2) a compendium or a reference to guide for decision-making and the implementation of actions within the industrial socio-technical systems.  相似文献   
895.
Geophagy, the deliberate ingestion of soil, is a widespread practice among animals, including humans. Although some cases are well documented, motivations and consequences of this practice on the health status of the consumer remain unclear. In this paper, we focused our study on chimpanzees (Pan troglodytes schweinfurthii) of the Kibale National Park, Uganda, after observing they sometimes ingest soil shortly before or after consuming some plant parts such as leaves of Trichilia rubescens, which have in vitro anti-malarial properties. Chemical and mineralogical analyses of soil eaten by chimpanzees and soil used by the local healer to treat diarrhoea revealed similar composition, the clay mineralogy being dominated by kaolinite. We modelled the interaction between samples of the two types of soil and the leaves of T. rubescens in gastric and intestinal compartments and assayed the anti-malarial properties of these solutions. Results obtained for both soil samples are similar and support the hypothesis that soil enhances the pharmacological properties of the bio-available gastric fraction. The adaptive function of geophagy is likely to be multi-factorial. Nevertheless, the medical literature and most of occidental people usually consider geophagy in humans as an aberrant behaviour, symptomatic of metabolic dysfunction. Our results provide a new evidence to view geophagy as a practice for maintaining health, explaining its persistence through evolution.  相似文献   
896.
The activities of 18 enzymes were measured in gill, hepatopancreas and muscle tissue of the deep-water crabsChaceon fenneri andC. quinquedens and the shallow-water crabCallinectes sapidus collected from the Gulf of Mexico in January 1989. The activities of catabolic enzymes were correlated in general with the known metabolic rates of the three species. Activities were much higher inC. sapidus than inChaceon fenneri andC. quinquedens. In some cases,C. quinquedens had higher activities thanC. fenneri. The activities of enzymes of amino acid metabolism (glutamate dehydrogenase and alanine aminotransferase) were higher inC. quinquedens, which had high hemolymph [ammonia] and ammonia excretion rates. The activity of lactate dehydrogenase (LDH) ofC. fenneri andC. quinquedens were correlated with the two species' abilities to withstand hypoxia. The more hypoxiatolerant species,C. quinquedens, had higher activity of LDH in its muscles than didC. fenneri.  相似文献   
897.
Summary. Many aquatic species use chemosensory information to assess predation risk. The cues used in such risk assessment can come either from the predator (predator odour) or from injured prey (alarm cues). The information conveyed through chemicals may, however, be inaccurate both spatially and temporally, as chemicals may persist in the environment long after the predator is gone. Thus, the level of accuracy of the cues for risk assessment may depend on the persistency of the chemicals in the habitat. Here, we investigated the persistency of alarm cues of a larval amphibian, the woodfrog (Rana sylvatica) in a ephemeral pond, their natural habitat. We introduced either alarm cues or control water in enclosed sleeves (~10 L) installed in the pond. The sleeve water was then sampled after 5 min and every two hours for eight hours. We used the behavioural response of woodfrog tadpoles to alarm cues as a bioassay to assess how long the alarm cues persisted in the environment. We found that tadpoles responded with an antipredator response to the pond water containing alarm cues 5 min after the injection of the cues in the sleeves but did not respond to that same pond water after two hours. Our results indicate that biodegradation and/or photodegradation of alarm cues in natural habitats might occur relatively quickly as the loss of a response to the cues in our experiment was independent of a dilution effect. This contrasts with previous laboratory results indicating that chemicals may be active after several hours.  相似文献   
898.
When resources are limited, life history theory predicts a trade-off between growth, reproduction and survival. In summer, lactating females of temperate large herbivores such as the white-tailed deer (Odocoileus virginianus) normally have access to abundant forage but also face the high energetic needs of lactation and recovery from winter mass loss. At high population density, however, females may face a trade-off between allocating resources for maintenance and for reproduction. To simulate the effects of increased intra-specific competition at high density, we measured for 2 years how an experimental food restriction of approximately 20% affected current reproduction and body mass changes of adult females and their fawns during the fawning and lactation periods. Fawn survival decreased 35%, and fawn growth decreased 26% in the food-restricted treatment. There was no effect of food restriction on female mass. Irrespective of treatment, however, lactating females gained 30 g/day less than non-lactating females, and females that had weaned a fawn the previous year gained 20 g/day less than females that had not. We conclude that when resources were scarce, females adopted a conservative strategy favouring their own survival, mass recovery and future reproductive potential over their current reproduction, probably to maximise their lifetime reproductive success.  相似文献   
899.
Geophagia, the deliberate ingestion of soil, is a complex eating behaviour with obscure aetiology and numerous health/medical problems. It is conventionally assumed that geophagia may help supplement mineral nutrients in individuals with limited intake of trace elements such as Fe and Zn. This view, however, has largely been based on the bulk nutrient composition of geophagic materials and the assumption that these nutrients are potentially available for absorption in the body. We have tested this assumption by equilibrating five geophagic materials collected from Uganda, Tanzania, Turkey and India with mineral nutrient concentrations and conditions similar to the gastrointestinal tract. The results showed that all five geophagic materials, regardless of their composition, sorbed large amounts of Fe and Zn across a range of dietary intake scenarios, even under acidic conditions (pH 2) similar to the stomach. However, significant amounts of Ca desorption were observed from calcareous soil samples. The findings show that while calcareous geophagic materials may supplement Ca, geophagia can potentially cause Fe- and Zn-deficiency. This is consistent with mineral nutrient deficiency problems observed in clinical nutrition studies conducted amongst geophagic populations.  相似文献   
900.
Organic contaminants that decrease the surface tension of water (surfactants) can have an effect on unsaturated flow through porous media due to the dependence of capillary pressure on surface tension. We used an intermediate-scale 2D flow cell (2.44 x 1.53 x 0.108 m) packed with a fine silica sand to investigate surfactant-induced flow perturbations. Surfactant solution (7% 1-butanol and dye tracer) was applied at a constant rate at a point source located on the soil surface above an unconfined synthetic aquifer with ambient groundwater flow and a capillary fringe of approximately 55 cm. A glass plate allowed for visual flow and transport observations. Thirty instrumentation stations consist of time domain reflectometry probes and tensiometers measured in-situ moisture content and pressure head, respectively. As surfactant solution was applied at the point source, a transient flow perturbation associated with the advance of the surfactant solution was observed. Above the top of the capillary fringe the advance of the surfactant solution caused a visible drainage front that radiated from the point source. Upon reaching the capillary fringe, the drainage front caused a localized depression of the capillary fringe below the point source because the air-entry pressure decreased in proportion to the decrease in surface tension caused by the surfactant. Eventually, a new capillary fringe height was established. The height of the depressed capillary fringe was proportional to height of the initial capillary fringe multiplied by the relative surface tension of the surfactant solution. The horizontal transport of surfactant in the depressed capillary fringe, driven primarily by the ambient groundwater flow, caused the propagation of a wedge-shaped drying front in the downgradient direction. Comparison of dye transport during the surfactant experiment to dye transport in an experiment without surfactant indicated that because surfactant-induced drainage decreased the storage capacity of the vadose zone, the dye breakthrough time to the water table was more than twice as fast when the contaminant solution contained surfactant. The extensive propagation of the drying front and the effect of vadose zone drainage on contaminant breakthrough time suggest the importance of considering surface tension effects on unsaturated flow and transport in systems containing surface-active organic contaminants or systems, where surfactants are used for remediation of the vadose zone or unconfined aquifers.  相似文献   
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