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1.
Air travelers can carry an infectious disease's pathogenic microorganism in their bodies and spread the disease from one country to another in a few days. To delay the spread, health screening stations may be set up at airport terminals to screen travelers. This research tested three different health screening strategies, each with a different combination of screening stations at trip origins, destinations and connecting airports. Discrete event simulations were performed, based on the 2014 to 2016 Ebola virus epidemic, with special focus on travelers from the West African countries traveling to the United States, including travelers who transferred flights at airports in European Union member states. The effectiveness of the screening strategies was analyzed in terms of correct detection, missed detection and false alarm rate. The results showed that exit screening at trip origins brought big improvements in the performance measurements compared to no screening. However, additional screening at the destinations and connecting airports contributed marginal benefits.  相似文献   
2.
This study examines the sources of labor productivity growth dynamics in Japan (1970–2010) and investigates the extent to which Japanese economic performance has been affected by Baumol's growth disease (BGD). We find that BGD silently undermines Japanese economic growth. However, the magnitude is miniscule, and consequently the aggregate labor productivity growth rate has not been decreasing monotonically. We also explore how BGD is arising and why it is small in the Japanese economy. BGD is weak because (1) the positive Baumol growth effect is also working in certain services sectors and (2) BGD is not a durable phenomenon: even if a sector begins to suffer from BGD, it is likely to recover quickly.  相似文献   
3.
平顶山矿区铁路线上有几十座钢筋混凝土桥梁,在使用过程中由于多种原因产生了各种裂缝,通过不同整治方法处理后,延长了桥梁的使用寿命,提高了桥梁的承载力。  相似文献   
4.
从心身医学的角度,阐述冠状动脉硬化性心脏病的病因学,心理生物学机制及防治;对现代社区医疗卫生工作中的老年疾病的康复保健具有一定的指导意义。  相似文献   
5.
现阶段,随着社会经济的飞速发展,道路基础设施的建设速度逐渐加快。同时,随着各种各样桥梁病害问题的出现,对桥梁的承载能力造成了一定程度的影响。因此,及时防治桥梁病害有助于保障桥梁的安全性。论文结合某危桥改造项目,对桥梁的病害展开研讨,对病害的产生原因进行分析,并提供实用性的桥梁设计应对方法,以保证桥梁的耐久性与安全性。  相似文献   
6.
亚洲石油大陆桥建设设想   总被引:1,自引:0,他引:1  
李岱 《经济地理》1996,16(3):52-56
本文提出了关于建设亚洲石油大陆桥设想的国际意义,以及我国参与建设的必要性,并构建了亚州石油大陆桥的基本框架,最后提出中国应采取的主要对策和措施.  相似文献   
7.
港澳珠大桥的方案选择与财务可行性分析   总被引:1,自引:0,他引:1  
赵大英 《经济地理》2004,24(5):633-637
首先介绍了港澳珠大桥的主要方案及分歧所在,然后从区域经济角度进行客货量预测,根据客货量预测和区域基础设施的发展规划,探讨大桥的功能定位并选择最佳方案——中线方案,最后根据客货量预测探讨了大桥的财务可行性,得出结论,港澳珠大桥财务可行。  相似文献   
8.
Abstract

Aims

To characterize a US population of patients with irritable bowel syndrome with constipation (IBS-C) or chronic idiopathic constipation (CIC) using CONTOR, a real-world longitudinal research platform that deterministically linked administrative claims data with patient-reported outcomes data among patients with these conditions.  相似文献   
9.
The disability-adjusted life year (DALY) is a summary health measure that combines mortality and morbidity into a single measure as a way to estimate global disease burden and the effectiveness of health interventions. We review the methodological progression of the DALY, focusing on how the use of life expectancy estimates, disability weights, age weighting, and discounting has evolved since the first DALY reports were published in 1993. These changes have generally improved the metric but have made it difficult for researchers to interpret, compare, and conduct DALY studies.  相似文献   
10.
There is growing concern that trade, by connecting geographically isolated regions, unintentionally facilitates the spread of invasive pathogens and pests – forms of biological pollution that pose significant risks to ecosystem and human health. We use a bioeconomic framework to examine whether trade always increases private risks, focusing specifically on pathogen risks from live animal trade. When the pathogens have already established and traders bear some private risk, we find two results that run counter to the conventional wisdom on trade. First, uncertainty about the disease status of individual animals held in inventory may increase the incentives to trade relative to the disease-free case. Second, trade may facilitate reduced long-run disease prevalence among buyers. These results arise because disease risks are endogenous due to dynamic feedback processes involving valuable inventories, and markets facilitate the management of private risks that producers face with or without trade.  相似文献   
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