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72.
对外农业投资是“一带一路”倡议的重要内容,研究美国对外农业投资特征,既可总结先行之国的发展经验,也可响应并适应主要竞争对手的投资行为,为充分利用两个市场、两种资源提供科学依据。本文立足对外直接投资理论,采用Logistic模型与面板数据分析方法,研究了2000-2018年美国对外农业投资的时空格局、影响因素及其对“一带一路”农业合作的启示。结果表明:(1)美国对外农业投资以食品加工等产前产后环节为主,主要分布于西欧等发达国家以及墨西哥、巴西等地理临近的发展中国家。(2)美国对外农业投资呈现显著的市场导向特征,同时也受到地理与文化距离、国家治理等东道国因素的影响。(3)对比中美对外农业投资特征,结合当前国际经贸形势与中国农业国际合作目标,建议中国进一步优化农业产业链布局,在促进实现联合国可持续发展目标的同时,提高中国在全球粮安领域的定价权与渠道把控力;进一步深耕既有对外农业投资市场,在降低地缘竞争压力的同时,充分挖掘潜在市场机会;关注“一带一路”沿线国家的农业技术需求,保证投资目标与东道国的投资需求相协调;尤需解决中国对外农业投资面临的文化与体制差异较大等现实问题,提高“一带一路”农业合作项目的可持续性。  相似文献   
73.
景区发展与其区位条件密切相关,处于优势区位的景区更容易获得优先快速发展。以“丝绸之路旅游带”为例,综合考虑资源、市场、交通及服务四大区位因子,将其视为证据,引入D-S证据理论对景区区位优势进行测度,以I~V级表征区位由优到劣的状态,最后对景区区位与旅游发展核心区进行对比。结果显示:(1)区位优势等级区域差异化显著,总体呈现由东南至西北逐级递减的空间分布规律,自I至V级,重心逐步向西北方向偏移。(2)各区位因子分布存在差异性,东南地区景区资源区位优于西北地区;市场区位地带间差异最为明显,存在“长尾”特征及陕西“一省独大”现象;交通区位内在差异性与区位优势相仿;服务区位已不再是制约景区区位的主要因子,但就单个省份来看,“核心—边缘”结构较为明显。(3)与景区旅游发展对比来看,二者具有明显的空间关联性,但仍存在一定程度的空间错位现象。  相似文献   
74.
A multinational collaborative study during the summer of 1983 addressed organizational alternatives in natural systems management. Participants were particularly interested in ways different governments attempted to resolve the disparity between the interconnected quality of nature and the compartmentalized structure of bureaucracies. Five patterns of organization have evolved to meet this challenge: mission agencies managing ecosystems; independent or interagency central environmental units: environmental units within mission agencies; environmental components within central planning units; and regional superagencies. The systems developed by five nations—the United States, Korea, Malaysia, the Philippines, and Thailand—are analyzed and compared in terms of these five patterns.  相似文献   
75.
在"一带一路"建设中加强资源环境保护工作,不仅适应全球可持续发展的共识,更是我国发挥绿色引领作用的体现,助力构建共同繁荣区域大合作的关键和保障。文章以乌兹别克斯坦为例,基于对该国的实地调研,分析研究其资源环境特点及管理体制对推进"一带一路"的可能影响,提出了我国在"一带一路"建设过程中加强资源环境保护工作的几点建议。  相似文献   
76.
随着医学模式从生物医学模式向生物—心理—社会医学模式的转变,心理社会因素对健康的影响日益加重。文章探讨职业紧张与健康的关系及其可能会给作业员工健康造成的损害和相关干预措施。得出:职业紧张对健康的影响是较长时间内过大的压力所表现出来的累积性反应,其发展过程是缓慢和渐进的,可能会出现高血压、冠心病、中风、睡眠障碍等症状,在日常工作中,有必要采取有针对性的干预措施,其最基本的办法是干预生产活动中的紧张因素,提高作业员工的控制和适应能力,最终达到良性循环。  相似文献   
77.
Bladder outlet obstructions are a diverse and heterogeneous group of developmental abnormalities that generally involve obstruction of the proximal urethra in the male fetus. Indications for prenatal intervention are few and are usually restricted to the male fetus because bladder outlet obstruction in female fetuses is usually caused by complex cloacal development anomalies. We report on a female fetus with an enlarged bladder and a dilated proximal urethra (known as typical keyhole sign). A vesicoamniotic shunt was performed despite non-reassuring prognostic factors, but the procedure resulted in a successful outcome. We propose that in selected cases of bladder outlet obstruction, fetal intervention should be considered even when the fetus is female. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
78.
Objectives: Though there is a growing body of literature on crash risks in the developed world, little is known about how well these models apply to motoring in developing countries, the context in which the majority of road traffic fatalities occur. This qualitative study explores factors perceived to influence crash risks for commercial drivers in Ghana.

Method: Twenty commercial drivers of varied ages and experience were sampled from 7 major lorry terminals in 3 regions (Greater Accra, Ashanti, and Volta) of Ghana. Data were collected through semistructured interviews.

Results: The participants identified some issues that are shared with drivers in the developed world, though moderated by the Ghanaian context. These included work pressures (e.g., fatigued driving), speeding, distracted driving, and inadequate vehicle maintenance. Other factors identified by participants are less frequently considered in research addressing driving behavior in developed countries. These included aggressive competition over passengers and corruption (e.g., improper licensing practices), among others.

Conclusion: The findings have implications for building a research base to support the development of road safety policy and interventions in developing countries.  相似文献   

79.
Objective: Road safety is an important public health issue worldwide. However, few studies have analyzed the association between criminalizing drunk driving and years of life lost (YLL) due to road traffic deaths (RTDs). Our study can provide useful information about this policy.

Methods: We used interrupted time-series analysis to find the changes in monthly YLL and RTD before and after law enforcement began using RTD data from 2008 to 2014 in Tianjin.

Results: After adjustment for seasonality, months, holidays, and the number of people in each district, criminalizing drunk driving was followed by a 11.1% (95% confidence interval [CI], 1.1–21.1%) reduction in risk of RTDs and a corresponding 778.1-year (95% CI, 200–1,355.1) reduction in monthly YLL. The reduction in YLL was especially significant among males, those aged 16–64 years old, and suburban residents.

Conclusions: This study highlights that the law can lead to a reduction in YLL due to RTDs in Tianjin, China. Large immediate public health benefits resulted from the new road traffic law in China. YLL provides a complementary measure for examining the effect of criminalization on drunk driving RTDs.  相似文献   

80.
Introduction: Speed limit enforcement cameras provide an effective approach to reduce vehicle speeds and the number of road accidents. However, it is still unclear whether the safety effects of speed cameras show durability over long periods of time. This paper analyses how the effects of speed cameras on road accidents change over time. A total number of 771 camera sites and 4787 potential control sites are observed for a period of 18 years (1999–2016) across England. Method: Covariates such as road class, crash history, speed limit, and annual average daily traffic (AADT) are included in the data set. A difference in difference (DID) based propensity score matching (PSM) method is employed to select proper control sites and estimate the treatment effects. The safety effects of speed cameras are then evaluated from a long-term perspective. The post-treatment period is divided into four equal-length periods: early, medium 1 and 2, and late. Results and Conclusions: The results show that speed cameras have significantly reduced the number of road accidents near the camera sites. However, the effects vary across different time periods. The safety effects of speed cameras experienced a sharp decrease during the medium periods after an initial period of highly reduced accidents (medium 1: −53.1%, medium 2: −40.7%) and recovered slightly during the late period. In addition, to evaluate the criteria for selecting camera sites in the UK, we further investigated whether speed cameras at high risk sites have better safety performance. The results show that while safety effects at high risk camera sites also decreased during the medium periods, the reduction was smaller (medium 1: −20.8%, medium 2: −2.1%). Practical Applications: Appropriate road traffic regulations and management, as well as proper camera sites selection criterion, are important to maintain the effectiveness of speed cameras.  相似文献   
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