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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.
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   
4.
Adaptive co-management brings together collaborative and adaptive approaches in pursuit of sustainable resource use and social-ecological resilience. Enthusiasm for this management approach, however, is countered by recent critiques regarding outcomes. A lack of evidence from consistent evaluation of adaptive co-management further exacerbates this situation. This paper revisits the issue of evaluation in natural resource management and recasts it in light of complex adaptive systems thinking. An evaluative framework for adaptive co-management is developed which directs attention toward three broad components: ecosystem conditions, livelihood outcomes and process and institutional conditions. Scale-specific parameters are offered for each component to facilitate systematic learning from experience and encourage cross-site comparisons. Conclusions highlight the importance of systematically incorporating evaluation into the adaptive co-management process and recognize the challenge for resource agencies and researchers to shift from a conventional to a complex adaptive system perspective.  相似文献   
5.
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   
6.
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   
7.
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   
8.
Problems in agriculture and land use are increasingly recognised as complex, uncertain, operating at multiple levels (field to global value chains) and involving social, economic, institutional, and technological change. This has implications for how projects navigate complexity to achieve impact. However, few studies have systematically evaluated how project actors engage with other actors to configure capabilities and resources across multiple levels in agricultural innovation systems (AIS), from the individual to the network, to mobilise and build systemic innovation capacity. An analytical framework conceptualising the nested configuration of capabilities at multiple levels in the AIS is applied to two projects that successfully tackled agricultural and land management problems of differing complexity: (i) improving lamb survival; and (ii) sustainable land management in New Zealand. Findings indicate that innovation capacity constitutes project actors interacting with other AIS actors to configure capabilities and resources at different levels of the AIS in order to leverage positive project path dependencies and break path dependencies that are created by existing and historical capability configurations. Project actors also balance exploiting existing innovation capabilities, as well as using adaptive capability for exploring and creating new capability configurations to respond to emerging circumstances. This implies that projects should have strategic ambidexterity in terms of how they combine exploiting existing and exploring new networks to access, combine, create, or disconnect certain capabilities to address ‘capability voids’ in AIS. This requires support to projects to constantly scrutinise, through reflexive monitoring by dedicated facilitators, specific agriculture and land use policies connected to major sustainable development models (e.g. climate smart agriculture, urban farming, smart farming). The can help assess whether the AIS provides the right mix of capabilities and whether this is adequately supported by innovation policy, to realize transformative policy objectives.  相似文献   
9.
李军 《科技和产业》2021,21(8):295-300
公路改扩建工程在广东省正处于快速发展时期,如何准确得到路面病害情况,是旧路处治方案制定面临的主要问题.依托开阳高速改扩建工程,采用三维探地雷达对旧路进行病害检测,得到道路表面及内部的病害分布情况,并分别与人工徒步调查路况及开挖后内部实际情况进行比对.结果表明:当三维探地雷达检测采样间距设置为2.0 cm、驻波时间设置为0.6 ms、时窗设置为85 ns时,可达到较好的检测精准度;三维探地雷达可实现对路面结构内部不同深度位置的裂缝病害进行探测,精确识别3 mm宽裂缝,并了解裂缝的发展方向及性质.  相似文献   
10.
This paper constructs a duplex banking network formed by credit relationships and information interaction via the banks’ balance sheet to model the structure of systemic risk and investigate the dynamic mechanism of contagion in terms of default and liquidity infection along with the factors that affect the extent of the contagion. We systematically explain the role that duplex banking networks play in different aspects of risk contagion. Through theoretical analysis and simulations, we conclude that asymmetric information interaction would increase the inflexibility of the system, which leads to liquidity shortage and possibly the collapse of the whole market. The weakness of systemic risk in the interior of the complex banking system can be characterized by the partial discount factor using illiquid assets in the information network. By improving the connectedness of the information network of the duplex networks, the spread of contagion can be partially slowed.  相似文献   
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