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321.
Recent agreements between host country governments and foreign investors in the resource industries reflect an effort to meet the objectives of both parties. In some cases majority government ownership is combined with management control and the right of veto on certain policy questions by the foreign investor. Imaginative tax formulas are built into agreements that combine the principle of excess profits taxes with that of a minimum DCF rate of return. Expropriation risk is being limited by employing a high debt-equity ratio. Foreign investors are agreeing to programmes and policies that promote host country economic and social development, while host country governments are quaranteeing foreign investors against changes in laws that would affect their profits.  相似文献   
322.
Effects of changing patterns of forest and impervious land covers on hydrologic regimes of watersheds were evaluated for urban and rural areas of the lower Cedar River drainage near Seattle, Washington. Land cover characterizations were used in a spatially explicit hydrology model to assess effects of land covers on watershed hydrology during presettlement conditions (full forest cover), 1991 and 1998. For the presettlement to 1991 period, urban watersheds showed decreases in forest covers (range 63% to 83%) and increases in impervious surfaces (range 43% to 71%). Rural watersheds showed similar patterns but smaller changes, with forest covers decreasing (range 28% to 34%) and impervious surfaces increasing (range 8% to 15%). For the 1991 and 1998 period, changes in forest covers for urban and rural watershed were <24%, with losses in some watersheds and regeneration in others. Impervious surfaces continued to increase, but increases were larger in rural (range 38% to 60%) than in urban watersheds (range 4% to 27%). Flood-frequency curves indicated that discharge rates (m sec–1) for all watersheds were higher in 1991 and 1998 than historical and suggested that chances for floods increase because of changing land covers. The largest increases in discharge rates were in urban watersheds, with rates for 2-year, 10-year, and 25-year recurrence intervals being more than two times greater than the rate during historical conditions. Changes in flow regimes were indicated by presettlement discharge levels of less frequent recurrence intervals (10-year and 25-year) occurring in posturbanization times (1991 and 1998) during more frequent intervals (2-year and 10-year). Normalized flows (m yr–1) of watersheds for 2-year, 10-year, and 25-year recurrence intervals indicate how flow regimes in 1991 and 1998 can change as functions of different areas of land covers. During 1991 and 1998, abrupt increases in flows occurred when forest covers were low (range 17% to 37%) and impervious surfaces were >46%. In contrast, the lowest flows occurred when forest covers were most extensive (range 59% to 81%) and impervious surfaces were <23%. We conclude that our use of spatial characterizations of impervious surfaces and forested covers in a spatially explicit hydrology model provides a robust approach for revealing how variations in different types and spatial distributions of land covers can affect flood regimes and flows of different watersheds.  相似文献   
323.
PROBLEM: Given the public safety risk posed by violation and crash repeaters and the substantial costs for state driver improvement programs, it is important that their effectiveness be scientifically demonstrated and that intervention programs are based on sound research findings. METHOD: Crash and traffic violation standardized effect sizes (d) representing 106 individual interventions were coded from 35 methodologically sound studies and analyzed using meta-analysis. RESULTS: Driver improvement intervention in general was associated with small but significant reductions in both crashes (dw = 0.03) and violations (dw = 0.06). Significant effects were found on both measures for warning letters, group meetings, individual hearings, and license suspense/revocation. Of the driver improvement interventions studied, license suspension/revocation was by far the most effective treatment for both crashes and violations (dw = 0.11 and 0.19). Since one of the objectives of license suspension/revocation is to eliminate driving for the period of suspension, it is possible that much or all of the effect is due to reduced exposure and/or more careful driving during the suspension interval. Results were mixed for other types of interventions, although distributing educational or informational material was not associated with any reductions. Interventions associated with violation reduction tended to also be associated with crash reduction, although the relationship was not very strong (r = .30). DISCUSSION: Although interpretation of the effect size estimates was complicated by almost ubiquitous heterogeneity, the results do suggest an overall positive impact of driver improvement interventions in general. IMPACT ON INDUSTRY: The results support the continued use of driver improvement interventions, chiefly warning letters, group meetings, individual hearings, and especially license suspension/revocation. The results also suggest that court-triggered traffic violator programs are less effective than interventions triggered by drivers license agencies.  相似文献   
324.
    
BACKGROUND: Motor vehicle injury is the major cause of mortality among young adults. Information about the individual characteristics of those who drive dangerously could enhance traffic safety programs. The goal of this research was to examine the association between various personality-related characteristics and risky driving behaviors. METHODS: Young adults in Michigan, USA (n = 5,362) were surveyed by telephone regarding several personality factors (risk-taking, hostility, aggression, tolerance of deviance, achievement expectations) and driving behaviors (competitive driving, risk-taking driving, high-risk driving, aggressive driving, and drink/driving). Michigan driver records were obtained to examine offenses, serious offenses, driving offense points, crashes and serious crashes in the three pre-interview years. Multivariate regression analyses, adjusting for age, race, and marital status were conducted separately by sex to identify personality factors related to driving. RESULTS: For men and women, greater risk-taking propensity, physical/verbal hostility, aggression, and tolerance of deviance were significant predictors of a competitive attitude toward driving, risk-taking driving, high-risk driving, driving aggression, and drink/driving. Greater risk-taking propensity, physical/verbal hostility, aggression, and to a small degree, expectations for achievement predicted higher numbers of offenses, serious offenses, and points. CONCLUSION: Traffic safety policies and programs could be enhanced through recognition of the role personality factors play in driving behavior and the incorporation of this knowledge into the design and implementation of interventions that modify the behaviors associated with them.  相似文献   
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327.
ABSTRACT: Pierre Perrault, member of a bourgeois provincial family whose roots were in the Touraine region of France, grew up in Paris. One of six illustrious brothers, all characterized by brilliance and diversity, he was educated as a lawyer but turned to finance and rose to a high position under King Louis XIV. Owing to political naivete and financial imprudence, he fell into disgrace and went bankrupt. He then became an amateur scientist and wrote a book on the origin of springs. This book broke almost wholly with the traditional authoritarianism of 2, 000 years'standing, and set hydrology on the modern path of observation and direct experiment, He developed the concept of the hydrological cycle, correctly accounting for the disposition of rainfall by evaporation, transpiration, ground-water recharge and runoff. Some of his ideas about specific processes were erroneous, but where he was wrong his errors were logically based. Much of his contribution to the foundation of scientific hydrology has been overlooked or distorted by historians and hydrologists alike.  相似文献   
328.
Antibiotic resistance analysis (ARA) was used to determine if enterococci of human origin were present in a stream (Spout Run) that passes through a rural nonsewered community (Millwood, VA). Millwood consists of 82 homes, all served by individual septic systems, and Spout Run drains a 5,800-ha karst topography watershed that contains large populations of livestock and wildlife. Periodic monitoring by state regulatory officials had resulted in Spout Run being placed on the Virginia impaired stream list and Millwood being categorized as an at-risk community. Stream samples were collected monthly and analyzed for fecal coliforms and enterococci (May 1999-May 2000); ARA was performed on enterococci stream isolates on a quarterly basis. All 117 stream samples were positive for fecal coliforms, and 32% exceeded the Virginia recreational water standard (1,000 fecal coliforms/100 mL). A library of 1,174 known source Enterococcus isolate antibiotic resistance profiles was constructed, and yielded correct classification rates of 94.6% for 203 human isolates, 93.7% for 734 livestock isolates, and 87.8% for 237 wildlife isolates. Antibiotic resistance analysis of 2,012 enterococcal isolates recovered from stream samples indicated isolates of human origin appeared throughout the stream as it passed through Millwood, with a yearly average of approximately 10% human, 40% wildlife, and 50% livestock. There were no human origin isolates in samples collected upstream from Millwood, and the percent human origin isolates declined downstream from Millwood. While a human signature was found in Spout Run, it was small compared with the proportion of isolates from livestock and wildlife.  相似文献   
329.
/ We examined data relative to species abundance, distribution, anddiversity patterns of reptiles and amphibians to determine how perceptionschange over time and with level of sampling effort. Location data werecompiled on more than one million individual captures or observations of 98species during a 44-year study period on the US Department of Energy's(DOE) Savannah River Site National Environmental Research Park (SRS-NERP) inSouth Carolina. We suggest that perceptions of herpetofaunal speciesdiversity are strongly dependent on level of effort and that land managementdecisions based on short-term data bases for some faunal groups could resultin serious errors in environmental management. We provide evidence thatacquiring information on biodiversity distribution patterns is compatiblewith multiyear spatially extensive research programs and also provide aperspective of what might be achieved if long-term, coordinated researchefforts were instituted nationwide.To conduct biotic surveys on government-managed lands, we recommend revisionsin the methods used by government agencies to acquire and report biodiversitydata. We suggest that government and industry employees engaged inbiodiversity survey efforts develop proficiency in field identification forone or more major taxonomic groups and be encouraged to measure the status ofpopulations quantitatively with consistent and reliable methodologies. Wealso suggest that widespread academic cooperation in the dissemination ofinformation on regional patterns of biodiversity could result byestablishment of a peer-reviewed, scientifically rigorous journal concernedwith status and trends of the biota of the United States. KEY WORDS: Abundance; Amphibian; Biodiversity; Distribution; Landmanagement; Reptile  相似文献   
330.
This paper offers some suggestions on, and encouragement for, how to be better at risk communication in times of agricultural crisis. During the foot and mouth epizootic, the British public, having no precedent to deal with such a rapid and widespread epizootic, no existing rules or conventions, and no social or political consensus, was forced to confront the facts of a perceived "economic disease. Foot and mouth appeared as an economic disease because the major push to eradicate it was motivated exclusively by trade and economic reasons and not because of threats it posed to the lives of human beings and livestock. The British public deferred responsibility to their elected officials for a speedy end to this non-life threatening viral epizootic. The latter, however, did not have a contingency plan in place to tackle such an extensive outbreak. The appeal to an existing policy, i.e., mass eradication, as the exclusive strategy of containment was a difficult pill for the public to swallow well before the end of the 226-day ordeal. Public outcry reflected (in part) serious misgivings about the lack of effective communication of risk-informed decisions between government agents and all concerned. The government's handling of the matter underestimated concerns and values about animal welfare, public trust, and the plight of farmers and rural communities. A general loss of trust by some segments of the public was exacerbated by perceived mismanagement and early fumbles by government agents.Public moral uneasiness during the crisis, while perhaps symbolic of growing discontent with an already fractured relationship with farmed animals and the state of animal farming today, arguably, also reflected deep disappointment in government agents to recognize inherently and conditionally normative assumptions in their argument as well as recognize their narrow conception of risk. Furthermore, broader stakeholder participation was clearly missing from the outset, especially with respect to the issue of vaccination. A greater appreciation for two-way risk communication is suggested for science-based public policy in agriculture, followed by suggestions on how to be more vigilant in the future.  相似文献   
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