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41.
The stated and revealed travel behavior of a sample of 60 rural drivers aged 54-92 years provided a basis to explore the potential effectiveness of two common driver's license restrictions aimed at older drivers: time of day and road class. The potential utility and impact of these restrictions have not been explored with revealed data for jurisdictions with a large population of rural older drivers where automobile dependence is high. Data were drawn from a multiday Global Positioning System-based travel diary survey of rural older drivers in New Brunswick, Canada. Revealed travel data showed that over 50 percent of the rural drivers in the sample did not drive after dark, and 40 percent drove less than 1 percent of their total surveyed kilometers on major highways, higher rates than from participant-stated responses. The proportion of participants taking night trips and traveling on major highways decreased with age. The majority of trips taken after dark by all participants had a rural destination. The average daily kilometers driven on major highways by men and women aged 75 years and older was nearly identical (1.79 km/day). These exposure considerations suggest that restricting night travel and major highway travel for the oldest rural drivers (75 years and older) may have limited utility given that the majority of participants did not drive in these situations, and for those who did, most of their trips were in rural areas where enforcement could be expected to be limited. A better approach may be to encourage increased self-regulation through training, age-friendly upgrades to transportation infrastructure to help rural older drivers stay driving safely as long as possible, and the development of appropriate rural alternatives to help a driver transition to nondriver. 相似文献
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Ruchira Sen Heather D. Ishak Trevor R. Kniffin Ulrich G. Mueller 《Behavioral ecology and sociobiology》2010,64(7):1125-1133
Interspecies or intraspecies cooperation can be stabilized evolutionarily if choosing partners favor beneficial partners and
discriminate against non-beneficial partners. We quantified such partner choice (symbiont choice) in the leafcutter ant Atta texana (Attini, Formicidae) by presenting the ants in a cafeteria-style preference assay with genotypically distinct fungal cultivars
from A. texana and Acromyrmex versicolor. Symbiont choice was measured as the ants' tendency to choose one or more cultivar(s) from several pure (axenic) cultivar
fragments and convert a given fungal fragment into a garden. Microsatellite DNA fingerprinting enabled us to identify the
cultivars chosen by the ants for their gardens. In 91% of the choice tests, A. texana workers combined multiple cultivars into a single intercropped, chimaeric garden, and the cultivars coexisted in such chimaeric
gardens for as long as 4 months. Coexistence of distinct fungal genotypes in chimaeric gardens appears to contradict a recent
model of cultivar competition postulating that each cultivar secretes incompatibility compounds harming other cultivars, which
presumably would preclude the intercropped polyculture observed in our experiments. Although we found no clear evidence of
novel, recombinant genotypes in the experimental chimaeric gardens, the intercropping of cultivar genotypes may occasionally
lead under natural conditions to exchange of genetic material between coexisting cultivars, thus introducing novel cultivar
genotypes into the leafcutter symbiosis. Symbiont choice by ants and any competition between coexisting cultivar strains in
chimaeric gardens do not appear to operate fast enough in our laboratory assay to convert chimaeric gardens into the monocultures
observed for A. texana under natural conditions. 相似文献
46.
Jonathan D. Choquette Jacqueline D. Litzgus Joanne X. Y. Gui Trevor E. Pitcher 《Conservation biology》2023,37(1):e14016
Advancements in the field of reintroduction biology are needed, but understanding of how to effectively conduct translocations, particularly with snakes, is lacking. We conducted a systematic review of snake translocation studies to identify potential tactics for reducing postrelease effects. We included studies on intentional, human-mediated, wild–wild, or captive–wild translocations to any location, regardless of motive or number of snakes translocated. Only studies that presented results for at least 1 of 4 outcomes (movement behavior, site fidelity, survival, or population establishment) were included. We systematically searched 4 databases for published studies and used 5 methods to search the gray literature. Our search and screening criteria yielded 121 data sources, representing 130 translocation cases. We quantified the association between 15 translocation tactics and short-term translocation outcomes by calculating odds ratios and used forest plots to display results. Snake translocations involved 47 species (from mainly 2 families), and most were motivated by research, were monitored for at least 6 months, occurred in North America, and took place from the 1990s onward. The odds of a positive snake translocation outcome were highest with release of captive reared or juvenile snakes, release of social groups together, delayed release, provision of environmental enrichment or social housing before release, or minimization of distance translocated. The odds of a positive outcome were lowest when snakes were released early in their active season. Our results do not demonstrate causation, but outcomes of snake translocation were associated with 8 tactics (4 of which were strongly correlated). In addition to targeted comparative studies, we recommend practitioners consider the possible influence of these tactics when planning snake translocations. 相似文献
47.
The authors commence by discussing the role of the United Nations (UN) Commission on Sustainable Development (CSD) in relation to the field of education. The report of the UN Secretary-General to the CSD, Promoting Education, Public Awareness and Training is then evaluated. Novel proposals for the development of an Education 21 programme and for the designation of the educational community as a major group are outlined and advocated. The paper concludes with sections on what was achieved and what remains to be done; recommendations for action are made. 相似文献
48.
Using a probabilistic approach in an ecological risk assessment simulation tool: test case for depleted uranium (DU) 总被引:1,自引:0,他引:1
A probabilistic approach was applied in an ecological risk assessment (ERA) to characterize risk and address uncertainty employing Monte Carlo simulations for assessing parameter and risk probabilistic distributions. This simulation tool (ERA) includes a Window's based interface, an interactive and modifiable database management system (DBMS) that addresses a food web at trophic levels, and a comprehensive evaluation of exposure pathways. To illustrate this model, ecological risks from depleted uranium (DU) exposure at the US Army Yuma Proving Ground (YPG) and Aberdeen Proving Ground (APG) were assessed and characterized. Probabilistic distributions showed that at YPG, a reduction in plant root weight is considered likely to occur (98% likelihood) from exposure to DU; for most terrestrial animals, likelihood for adverse reproduction effects ranges from 0.1% to 44%. However, for the lesser long-nosed bat, the effects are expected to occur (>99% likelihood) through the reduction in size and weight of offspring. Based on available DU data for the firing range at APG, DU uptake will not likely affect survival of aquatic plants and animals (<0.1% likelihood). Based on field and laboratory studies conducted at APG and YPG on pocket mice, kangaroo rat, white-throated woodrat, deer, and milfoil, body burden concentrations observed fall into the distributions simulated at both sites. 相似文献
49.
Langdon CJ Piearce TG Meharg AA Semple KT 《Environmental pollution (Barking, Essex : 1987)》2003,124(3):361-373
Chemical pollution of the environment has become a major source of concern. In particular, many studies have investigated the impact of pollution on biota in the environment. Studies on metalliferous contaminated mine spoil wastes have shown that some soil organisms have the capability to become resistant to metal/metalloid toxicity. Earthworms are known to inhabit arsenic-rich metalliferous soils and, due to their intimate contact with the soil, in both the solid and aqueous phases, are likely to accumulate contaminants present in mine spoil. Earthworms that inhabit metalliferous contaminated soils must have developed mechanisms of resistance to the toxins found in these soils. The mechanisms of resistance are not fully understood; they may involve physiological adaptation (acclimation) or be genetic. This review discusses the relationships between earthworms and arsenic-rich mine spoil wastes, looking critically at resistance and possible mechanisms of resistance, in relation to soil edaphic factors and possible trophic transfer routes. 相似文献
50.
Trevor A. Byer 《Natural resources forum》1979,3(2):117-132
The analysis shows the impact of the 'New International Energy Order' on Jamaica, a developing country almost totally dependent on imported oil for satisfying national energy demand. The energy supply/demand situation between 1961 and 1976 and the structure of energy consumption by major sectors of the economy are discussed. The high income elasticity of commercial energy demand and the increase in the energy intensity of the economy is directly related to expansion of the alumina industry. The structural problems of decoupling GDP and energy growth are indicated. In particular, the impact of the 'New Energy Order' on the development prospects of major bauxite/alumina producing countries which are deficient in indigenous primary energy resources is assessed. Finally, the indigenous resource base is outlined and the major elements of the five-year (1978–1982) national energy plan summarized. 相似文献