780 research outputs found
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Food systems and diets: Facing the challenges of the 21st century
The world is facing a nutrition crisis: approximately three billion people from every one of the world’s 193 countries have low-quality diets. Over the next 20 years, multiple forms of malnutrition will pose increasingly serious threats to global health. Population growth combined with climate change will place increasing stress on food systems, particularly in Africa and Asia where there will be an additional two billion people by 2050. At the same time, rapidly increasing urbanization, particularly in these two regions, will affect hunger and nutrition in complex ways – both positively and negatively. Unless policy makers apply the brakes on overweight, obesity and diet-related disease and accelerate efforts to reduce undernutrition, everyone will pay a heavy price: death, disease, economic losses and degradation of the environment. A response, equivalent to that marshalled to tackle HIV/AIDS, malaria and smoking is needed to meet these challenges. Around the world, coordinated action needs to be accompanied by fundamental shifts in our understanding and in our policy actions. Much more emphasis must be given to positioning agricultural growth as a way to improve diet quality, rather than merely delivering sufficient calories. Food systems need to be repositioned from just supplying food to providing high-quality diets for all. This will require policy initiatives far beyond agriculture to encompass trade, the environment and health, which harness the power of the private sector and empower consumers to demand better diets. This report is a call to action for world leaders and their governments. Leadership and commitment will be essential in driving forward the decisions set out in this report and in delivering the necessary priority actions to reshape the global food system
Simulating Virtual Organizations for Research: A Comparative Empirical Evaluation of Text-Based, Video, and Virtual Reality Video Vignettes
Due to recent technological developments, vignette studies that have traditionally been done in text or video formats can now be done in immersive formats using virtual reality—but are such virtual reality video vignettes superior to traditional vignettes? To address this question, we examine participants’ experiences within a fictitious organization by comparing their responses to a relevant and particularly sensitive organizational phenomenon presented either through written text, a video recording, or a virtual reality experience. The results indicate that participants prefer more immersive methods, and that these increase their attention to critical study details. Moreover, this augments the effect sizes of several measured employee reactions—particularly those with high emotional content—suggesting that virtual reality technology offers a promising avenue for developing ecologically valid vignette studies to measure employee affect. To facilitate and expediate the use of virtual reality video vignettes in organizational research, we provide organizational scholars with a step-by-step instructional guide to develop immersive vignette studies
Underperforming policy networks : the biopesticides network in the United Kingdom
Loosely integrated and incomplete policy networks have been neglected in the literature. They are important to consider in terms of understanding network underperformance. The effective delivery and formulation of policy requires networks that are not incomplete or underperforming. The biopesticides policy network in the United Kingdom is considered and its components identified with an emphasis on the lack of integration of retailers and environmental groups. The nature of the network constrains the actions of its agents and frustrates the achievement of policy goals. A study of this relatively immature policy network also allows for a focus on network formation. The state, via an external central government department, has been a key factor in the development of the network. Therefore, it is important to incorporate such factors more systematically into understandings of network formation. Feedback efforts from policy have increased interactions between productionist actors but the sphere of consumption remains insufficiently articulated
Public-private partnerships for biosecurity: an opportunity for risk sharing
Private efforts to prevent and control biological pests and infectious diseases can be a public good, and so incentivising private biosecurity management actions is both desirable and problematic. Compensation contracts can encourage biosecurity efforts, provide support against the collapse of economic sectors, and create an insurance network. We conceptualise a novel biosecurity instrument relying on formal compensation private–public partnerships using contract theory. Our framework explains how the public sector can harness increased private biosecurity measures by making payments to agents which depend both on their performance and that of the other stakeholders. Doing so allows the government to spread the risk across signatory agents. The framework also improves our understanding of government involvement due to public effects of biosecurity, influenced by the private agents’ capacity to derive private benefit from their own efforts on monitoring and control. Lastly, these theoretical results provide a foundation for further study of contractual responsibility sharing for pest management
Optimal Patch-Leaving Behaviour: A Case Study Using The Parasitoid Cotesia rebecula
1. Parasitoids are predicted to spend longer in patches with more hosts, but previous work on Cotesia rubecula (Marshall) has not upheld this prediction. Tests of theoretical predictions may be affected by the definition of patch leaving behaviour, which is often ambiguous. 2. In this study whole plants were considered as patches and assumed that wasps move within patches by means of walking or flying. Within-patch and between-patch flights were distinguished based on flight distance. The quality of this classification was tested statistically by examination of log-survivor curves of flight times. 3. Wasps remained longer in patches with higher host densities, which is consistent with predictions of the marginal value theorem (Charnov 1976). Under the assumption that each flight indicates a patch departure, there is no relationship between host density and leaving tendency. 4. Oviposition influences the patch leaving behaviour of wasps in a count down fashion (Driessen et al. 1995), as predicted by an optimal foraging model (Tenhumberg, Keller & Possingham 2001). 5. Wasps spend significantly longer in the first patch encountered following release, resulting in an increased rate of superparasitism
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