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41.
The blossoming trade war betwee China and the United States has just been warmed-up a notch. A new body comprising seven US-based solar cell and module makers calling themselves the Coalition for Ameri...  相似文献   
42.
The main objective of this study is to investigate the impact of corporate research and development (R&D) activities on firm performance, measured by labour productivity. To this end, the stochastic frontier technique is used on a unique unbalanced longitudinal dataset comprising top European R&D investors over the period 2000–2005. In this framework, this study quantifies technical inefficiency of individual firms. From a policy perspective, the results of this study suggest that if the aim is to leverage firms’ productivity, the emphasis should be put on supporting corporate R&D in high-tech sectors and, to some extent, in medium-tech sectors. On the other hand, corporate R&D in the low-tech sector is found to have a minor effect in explaining productivity. Instead, encouraging investment in fixed assets appears important for the productivity of low-tech industries. Hence, the allocation of support for corporate R&D seems to be as important as its overall increase and an ‘erga omnes’ approach across all sectors appears inappropriate. However, with regard to technical efficiency, R&D intensity is found to be a pivotal factor in explaining firm efficiency and this turns out to be true for all industries.  相似文献   
43.
In this article, we use data for 376 households, 1,066 parcels, and 2,143 plots located in 95 villages in the hillside areas in Honduras to generate information needed by decision makers to assess the needs and opportunities for public investments, and design policies that stimulate natural resource conservation. We develop a quantitative livelihood approach, using factor and cluster analysis to group households based on the use of their main assets. This resulted in seven household categories that pursue similar livelihood strategies. We use a multinomial logit model to show that livelihood strategies are determined by comparative advantages as reflected by a combination of biophysical and socioeconomic variables. While 92% of the rural hillsides population in Honduras lives on US$1.00/capita/day or less, households that follow a livelihood strategy based on basic grain farming are the poorest because they often live in isolated areas with relatively poor agro‐ecological and socioeconomic conditions. Opportunities for off‐farm work tend to be limited in these areas and household strategies that combine on‐farm work with off‐farm work earn higher incomes. Per capita incomes can be increased by improving road infrastructure, widening access to land, policies that reduce household size and dependency ratios, and adoption of sustainable land management technologies that restore soil fertility. We used probit models to show that the latter can be promoted by agricultural extension programs and land redistribution. Investments in physical assets should be directed toward households that pursue livelihood strategies based on off‐farm employment or coffee production, while agricultural training programs are best focused on livestock producers.  相似文献   
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In less favoured areas such as the highlands of Ethiopia, farmers manage risk through land allocation to crops and varieties since they cannot depend on market mechanisms to cope. They also grow traditional varieties that are genetically diverse and have potential social value. Supporting the maintenance of crop and variety diversity in such locations can address both the current needs of farmers and future needs of society, though it entails numerous policy challenges. We estimate a model of crop and variety choice in a theoretical framework of the farm household model to compare the determinants of crop and variety diversity, revealing some of these policy considerations. Farm physical features and household characteristics such as wealth and labour stocks have large and significant effects on both the diversity among and within cereal crops, varying among crops. Policies designed to encourage variety diversity in one cereal crop may have opposing effects in another crop. Trade-offs between development-related factors and diversity in this resource-poor system are not evident, however. Market-related variables and population density have ambiguous effects. Education positively influences cereal crop diversity. Growing modern varieties of maize or wheat does not detract from the richness or evenness of these cereals on household farms.  相似文献   
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Diagnostic theories are fundamental to Information Systems practice and are represented in trees. One way of creating diagnostic trees is by employing independent experts to construct such trees and compare them. However, good measures of similarity to compare diagnostic trees have not been identified. This paper presents an analysis of the suitability of various measures of association to determine the similarity of two diagnostic trees using bootstrap simulations. We find that three measures of association, Goodman and Kruskal’s Lambda, Cohen’s Kappa, and Goodman and Kruskal’s Gamma (J Am Stat Assoc 49(268):732–764, 1954) each behave differently depending on what is inconsistent between the two trees thus providing both measures for assessing alignment between two trees developed by independent experts as well as identifying the causes of the differences.  相似文献   
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The World Expo,much like the Olympics and the World Cup,is a top global event bringing together countries from the farthest regions of the world.  相似文献   
49.
Changes in diet and nutrition, along with other lifestyle changes during the last decades, have affected the nutrition-related disease profile in many developing countries. This phenomenon, or process, is known as ‘The Nutrition Transition’. Several studies on adolescents in South Africa have shown that overweight and obesity are increasing, possibly due to this process. The aim of the present study was to extend our knowledge on the nutrition transition and the factors that influence adolescents’ choice of food in South Africa, and to develop policy recommendations that could facilitate the adolescents’ right to adequate food as laid down in the South African Constitutional Bill of Rights. The data were collected through focus groups with 25 female learners (grade 10, 14–16 years) from urban public schools in Cape Town and key informant interviews with 10 school staff members. The most important nutritional concerns that emerged from the analyses, included skipping breakfast and the consumption of unhealthy tuck shop food. In terms of the human right to adequate food, these findings reflected lack of availability and access to adequate food within the household, at schools, and in the community. In addition, the study showed that there were no or few opportunities for physical activity for adolescents during and after school hours. Social factors, including social norms and a need to conform to peer group pressure, appeared to affect the behaviour of learners considerably. Traditional foods appeared to have lost their importance, while learners preferred to consume fast foods and to adopt a more westernised diet connected to affluence and social acceptance. Traditional and more “Western” body perceptions co-existed among the study participants. The nutrition transition in South Africa is of a complex nature because of large differences that exist amongst different ethnic and socioeconomic groups. Policy decisions should be based on an understanding of these diverse factors. The media and the food industry should be encouraged to work with government in influencing adolescents to make healthy food choices. Cultural perceptions which may lead to unhealthy choices and lifestyle need to be addressed while at the same time respecting people’s cultural pride and human dignity. It is recommended that human rights principles are used purposively in the future in policy formulations, interventions, evaluation and monitoring.  相似文献   
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