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991.
现代农业生物技术对中国未来经济和全球贸易的影响 总被引:7,自引:0,他引:7
一场有关中国是否应该继续加速推进其转基因生物技术和是否应将转
基因粮食作物商业化的争论正在激烈地进行,这一争论对现代生物技术在中国的应用产生了
影响。本文根据转基因棉花商业化的调查数据和转基因水稻的田间实验数据,在分析不同情
况下采用转基因农作物对中国和其他国家和地区的生产、贸易和福利影响的基础上,对转基
因棉花和水稻的影响进行了全面的经济评估。在此基础上提出了中国发展生物技术的政策建
议。 相似文献
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Those involved in training know that creating instructional materials can become a tedious, repetitive process. They also know that business conditions often require training interventions to be delivered in ways that are not ideally structured or timed. This article examines the notion that learning objects can be reused and adapted for performance support systems. By doing so, a performance technologist can develop content for just‐in‐case training and reuse it for just‐in‐time performance support. 相似文献
996.
The purpose of this investigation was to identify and describe the differences in the methods used by faculty teaching introductory chemistry and students enrolled in an introductory chemistry course at the university level to solve paired algorithmic and conceptual problems. Of the 180 students involved, the problem-solving schemas of 20 selected students and 2 professors were evaluated using a graphical method to dissect their think-aloud interviews into episodes indicative of solutions to paired problems on density, stoichiometry, bonding, and gas laws. The interviewed students were classified into four different problem-solving categories (i.e., high algorithmic/high conceptual, high algorithmic/low conceptual, low algorithmic/high conceptual, and low algorithmic/low conceptual), and composite graphs of their problem-solving schemas were compared to those representative of members of the faculty experts' category. Results of these comparisons indicated that as the students' ability to solve both algorithmic and conceptual problems improved, less time and fewer transitions between episodes of the problem-solving schemas were required to complete the problems. Regardless of the students' problem-solving ability, algorithmic-mode problems always required more time and a greater number of transitions for completion than did the paired conceptual-mode problems. However, regardless of topic, all students more frequently correctly solved the algorithmic-mode problems than the corresponding paired conceptual-mode problems. © 1997 John Wiley & Sons, Inc. J Res Sci Teach 34: 905–923, 1997. 相似文献
997.
María Eugenia Pedreira Arturo Romano Daniel Tomsic Mariana Lozada Héctor Maldonado 《Learning & behavior》1998,26(1):34-45
The crabChasmagnathus granulatus reacts to a shadow passing overhead with an escape response that habituates after 30 trials and for 5 days at least. The effect of a wide range of different intertrial intervals (ITIs) (0, 9, 27, 45, 81, 135, and 171 sec) on theChasmagnathus long-term habituation (LTH) was evaluated at 24 h. Memory retention was estimated separately at two phases of a six-trial testing session: at first trial (the initial testing phase) and at the subsequent block of five trials (the retraining phase). A training of 30 trials with an ITI equal to or longer than 27 sec induced LTH at both testing phases, however, with a 0- or a 9-sec ITI, training wholly failed to build up LTH. When the number of trials was increased, a massed training (ITI=0 or 9 sec) induced LTH at retraining but not at initial testing. Thus, massed training produces LTH only at retraining, whereas spaced training (ITI ≥ 27 sec) produces LTH at both initial phase and retraining. An ITI shift from training to testing diminished or abolished retention at retraining regardless of the direction of the shift, thus suggesting that crabs acquire a memory of the trial-spacing at training. According to these results, it is postulated that LTH consists of two memory components: one produced by spaced training and expressed at both initial testing and retraining, and one yielded by massed training and expressed only at retraining. The possibility that the two components of LTH were differentially affected by cycloxemide and context shift is discussed. 相似文献
998.
Dante D. Dixson Paula Olszewski-Kubilius Rena F. Subotnik Frank C. Worrell 《Psychology in the schools》2020,57(10):1582-1595
In this article, we explore how school psychologists who adopt a talent development perspective can play a larger role in cultivating the talent of academically gifted students. Utilizing the talent development megamodel and Ackerman's model of expertise, we outline how school psychologists can consult with school administrators, teachers, and parents to meet the general and domain-specific academic needs of academically gifted students at home and in school. In addition, we discuss how school psychologists can leverage systems of assessment (e.g., universal screening, continued assessment) to identify academically gifted students across academic talent trajectories as well as provide students with multiple opportunities to exhibit their academic talents. We conclude by highlighting some diversity and multi-cultural considerations that school psychologists should keep in mind while developing academic talent, as well as a policy implication of school psychologists adopting a talent development approach to their work. 相似文献
999.
Martijn Burger Spyridon Stavropoulos Shyaam Ramkumar Joke Dufourmont Frank van Oort 《Research Policy》2019,48(1):248-261
This paper examines the opportunities and risks of employment, skills and education that are related to a circular economy (CE) in the United States. Combining occupational skills and education data with a newly introduced definition of CE employment, we compare circular- and non-circular-oriented occupations in terms of skills and abilities. Building on the seminal paper by Consoli et al. (2016) and looking at all occupations within a broad range of CE-related industries, we detect and address heterogeneity in job requirements within the CE. We distinguish core activities within CE employment – focusing on renewable energy, repair, re-use of materials and the sharing economy – from enabling activities, which are focused on management, design, and ICT-applicability of the CE. While core CE-activities generally require more manual and technological skills, enabling activities, in contrast, require more complex cognitive skills. Neither core nor enabling CE sectors, however, are entirely cohesive in terms of skill requirements. Part of the education and skills demand is identifiably driven by ‘circularity’, particularly with regard to technical skills for the core of the CE. This may require specific education and training programs for future development of the CE. 相似文献
1000.
Over the past decade the scale of higher education in China has expanded substantially. Regional development policies have attempted to make use of scale expansion as a tool to reduce inequality of higher education among regions with different development levels by providing poor regions with preferential treatment and support. This paper analyzes a provincial dataset (1997–2008), aiming to provide comprehensive quantitative evidence for the development of inequality of opportunity in higher education across provinces in China over the period of scale expansion. Results show that, for higher education, regional inequality relative to provincial population size clearly decreased over the research period. Accompanying the reduction in overall inequality across provinces, inequality between poor and rich regions actually increased over the same period. However, the increase was realized in favor of the poor region. The empirical results are consistent with the policy orientation of reforming the higher education system and of promoting regional development in China over the past decade. 相似文献