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991.
《Food Policy》2013
The use of genetically modified (GM) crop technology in tackling food security problems and poverty reduction in Africa continues to generate debates over its benefits and safety. Only four countries, South Africa, Sudan, Burkina Faso and Egypt have commercialized GM crops in Africa but controversy surrounds current cultivation of GM maize in Egypt. Our study provides new perspectives on the status, development and regulation of GM crops through examining the views of 305 stakeholders in six African countries across four regions: South Africa, Kenya (East Africa), Egypt and Tunisia (North Africa), Ghana and Nigeria (West Africa), supplemented by interviews with relevant international organizations. The study revealed the challenges leading to the development of biosafety regulatory frameworks and the role of individual stakeholders in the facilitation of GM crops across African countries. This study also revealed that some countries may go through a Fiber–Feed–Food (F3) approach to adopt GM crops where Bt cotton will be adopted first followed by GM crops for livestock feed while undergoing all the necessary assessments before producing GM foods for human consumption. An overwhelming majority of stakeholders placed emphasis on risk analysis (risk assessment and management) in view of limited capacity, lack of scientific expertise and public concern, and encouraged a centralized approach to risk assessment similar to the European Union model of the European Food Safety Authority (EFSA). 相似文献
992.
《Food Policy》2013
Using nationally-representative household survey data and confidential geo-coded data on violent incidents, we examine the relationship between conflict and food insecurity in Afghanistan. Spatial mappings of the raw data reveal large variations in levels of food insecurity and conflict across the country; surprisingly, high conflict provinces are not the most food insecure. Using a simple bivariate regression model of conflict (violent incidents and persons killed or injured) on food security (calorie intake and the real value of food consumed), we find mixed associations. But once we move to a multivariate framework, accounting for household characteristics and key commodity prices, we find robust evidence that in Afghanistan levels of conflict and food security are negatively correlated. We also find that households in provinces with higher levels of conflict experience muted declines in food security due to staple food price increases relative tohouseholds in provinces with lower levels of conflict, perhaps because the former are more disconnected from markets. Gaining a better understanding of linkages between conflict and food insecurity and knowing their spatial distributions can serve to inform policymakers interested in targeting scarce resources to vulnerable populations, for example, through the placement of strategic grain reserves or targeted food assistance programs. 相似文献
993.
《Food Policy》2016
This paper identifies several positive synergies between social protection programmes and enhanced entitlements to food. One function of social protection is to manage or reduce vulnerability. Several instruments are reviewed – weather-indexed insurance, public works programmes, emergency food aid and buffer stock management – which aim to stabilise income and access to food across good and bad years, or between the harvest and the hungry season. Other social protection instruments aim to raise household income and crop production, for instance agricultural input subsidies or input trade fairs, as well as public works projects that construct or maintain physical infrastructure such as rural feeder roads. This paper also argues that entitlements to food can be strengthened if social justice principles are introduced to the design and delivery of social protection programmes. Examples reviewed include rights-based approaches such as employment guarantee schemes, community-based targeting and demand-driven accountability mechanisms. The paper concludes by arguing for a comprehensive approach to social protection that will achieve sustainable food security, by combining interventions that stabilise income or food production with those that raise income or food production, and are designed and delivered in ways that enhance social justice. 相似文献
994.
Feng Guo 《Review of Financial Economics》2019,37(2):297-321
Following the approach of interpolation, this paper proposes the multiple exponential decay model to fit yield curves for both the U.S. TIPS market and the conventional Treasury security market. Several estimation methods, including the unconstrained/constrained nonlinear minimization, quadratic programming, and the iterative linear least squares, are applied to estimate the unknown parameters according to different curve‐fitting purposes. Comparisons between the proposed model and the alternatives show that the multiple exponential decay successfully (1) adapts to a variety of shapes associated with yield curves, (2) (partially) keeps in line with the economic interpretations of Nelson–Siegel summarized by Diebold and Li ( 2006 ), and (3) dominates the competing models in curve‐fitting performance measured by mean fitted‐price errors over the sample period. In addition, the exact specification of a nonparametric interpolation model is pinned down by applying three statistical tools, which enable us to jointly take into account validity, optimality, and parsimoniousness of the proposed model. 相似文献
995.
Information security management plays an essential role for drawing the roadmap of information security; thus, many theoretical methodologies and practical standards are brought into this domain. However, many standards and methodologies are too cumbersome to be adopted by an organization. Additionally, there is no unified framework to systematically handle the tedious tasks of information security management. This study’s primary goal is to design an integrated system for information security management (ISISM) that aims to use current methodologies and standards to solve the above-mentioned issues. Because business impact analysis and risk analysis are the most important areas within this domain, we carefully select the related methods and then integrate them into a unified framework, upon which the proposed ISISM depends. To achieve this outcome for this study, security requirement engineering is adopted, which enables the designed system to support system users in generating risk assessment reports with related information security policies. 相似文献
996.
There is scant research on the impact of unionization on hospitality employees’ job security, health, and working conditions. This research explores employees’ beliefs of costs and benefits of unionization in hospitality organizations given that previous research has mainly focused on its influence on the firm and the industry. The findings of this study suggest that unionization can present a unique set of challenges both for line-level employees and managers. The ‘it’s not my job’ attitude associated with unionization can have a dampening impact on employees’ future career opportunities. Future research needs to consider the long-term consequences of unionization on employees. 相似文献
997.
As the global population increases and transportation connectivity improves in quality and prices, the demand for mobility increases, especially in long-haul services. According to the 2017 report of the European Commission in Mobility and Transport, the performance of all modes for passenger transport (roadways and airways) are reaching record highs. Although the benefits of the increased demand for mobility are substantial and welcome, an effort should be paid such as to ameliorate possible threatening side-effects that may also arise. As World Health Organization (WHO) denotes and as has been evident from the global COVID-19 epidemic outbreak, infectious diseases can be spread directly or indirectly from one person to another under common exposure circumstances such as air transportation (especially long-haul airline connections) that may act as the medium for transmitting and spreading infectious diseases. In this paper, analytical and realistic models have been integrated, for providing evidence on the spread dynamics of infectious diseases that may face Europe through the airlines system. In particular, a detailed epidemiological model has been integrated with the airlines’ and land transport network, able to simulate the epidemic spread of infectious diseases originated from distant locations. Additionally, a wide set of experiments and simulations have been conducted, providing results from detailed stress-tests covering both mild as well as aggressive cases of epidemic spreading scenarios. The results provide convincing evidence on the effectiveness that the European airports' system offer in controlling the emergence of epidemics, but also on the time and extent that controlling measures should be taken in order to break the chain of infections in realistic cases. 相似文献
998.
Andrew Cheon 《Economics & Politics》2019,31(3):403-427
National oil companies (NOCs) have invested hundreds of billions of dollars in foreign oil and gas assets. Why have some governments increased their NOC outward investments, while others have not? I argue that domestic structures can influence a government's calculus that potential benefits, such as added revenues and fuel supply, outweigh potential costs, such as information asymmetries and inefficiencies associated with NOCs. Nationally, partisan competition limits democratic tolerance for failures by NOCs. Bureaucratically, overlapping authority in energy policy undermines coherent NOC governance. Based on investments by NOCs hailing from 79 countries, 2000–2013, I find robust evidence for the national hypothesis. 相似文献
999.
《Bulletin of economic research》2018,70(2):175-184
This paper will set up a general equilibrium model with a distorted labour market to explore the effects of an environmental tax and union bargaining power on formal employment and the informal competitive wage. We find that when the government raises the environmental tax, both formal employment and informal competitive wage would fall. In addition, we confirm that a policy of labour market reform would increase both formal employment and the informal competitive wage. 相似文献
1000.