共查询到20条相似文献，搜索用时 31 毫秒
1.
《Higher Education Policy》2001,14(1):7-20
The relationship between governments and higher education institutions has been changing in Europe over the last few decades. The mechanisms of steering and regulation have moved away from the model of centralised control by allowing more institutional autonomy. Even if the government has been using an increasing array of market and market-like mechanisms instead of more traditional regulation mechanisms, the state has not really stepped back in favour of the market, and this has led to a hybrid situation where increased institutional autonomy is still facing significant government regulation — the Janus Head effect. It is our opinion that the regulation of higher education cannot be left in the sole hands of the market, and for this reason hybridism can play a very important role. 相似文献
2.
Because brushless direct current (BLDC) motors have the advantages of a compact size, high power density, high efficiency, and long operating life time, they are widely used in many industrial products and electric traction systems. It is known that the BLDC motors have no brushes for commutation. They are commutated with electronically commutation. So, the rotor position information of the BLDC motors must be known to understand which winding will be energized according to the energizing sequence. In most of the existing BLDC motor drivers, rotor position information is detected by Hall effect sensors. This kind of mechanical position sensors will bring additional connections and costs, reliability decrease and noise increase. In order to improve the control performance and extend the range of speed regulation for BLDC motors, a position sensorless control method is proposed in this paper. In the proposed control method, rotor position information of the BLDC motors is detected from the back electromagnetic forces (back-EMFs) which are estimated by an unknown-input observer with line to line currents and line to line voltages. For the purpose of verifying the effectiveness of the proposed control method, a model is built and simulated on the Matlab/Simulink platform. The simulation results show that the speed regulation performance of BLDC motors is improved compared with using Hall effect sensors. At the same time, the reliability of the BLDC motors is improved and the costs of them are reduced because the position sensor is eliminated. 相似文献
3.
Type-dependent differential expression of neuropeptide Y in chicken hypothalamus （Gallus domesticus）
Chen GQ Hu XF Sugahara K Chen JS Song XM Zheng HC Jiang YQ Huang X Jiang JF Zhou WD 《Journal of Zhejiang University. Science. B》2007,8(11):839-844
Neuropeptide Y (NPY) is one of the most important orexigenic agents in central regulation of feeding behavior, body weight and energy homeostasis in domestic chickens. To examine differences in the hypothalamic NPY between layer-type and meat-type of chickens, which are two divergent kinds of the domestic chickens in feeding behavior and body weight, we detected mRNA levels of NPY in hypothalamic infundibular nucleus (IN), paraventricular nucleus (PVN) and lateral hypothalamic area (LHA) of these two types of chickens using one-step real time RT-PCR. The meat-type chicken had more food daily (about 1.7 folds) and greater body weights (about 1.5 folds) and brain weights than the layer-type chicken at the age of 14 d. In the meat-type of chicken, NPY mRNA levels of the IN and PVN were significantly greater than those of the LHA, and were not significantly different between the IN and PVN. However, in the layer-type of chicken, NPY mRNA levels were significantly greater in the IN than those in the LHA and PVN, and were not significantly different between the PVN and LHA. In all these hypothalamic regions, the layer-type of chicken had significantly higher NPY mRNA levels than the meat-type chicken did. These results suggest the expression of NPY in the hypothalamus has a type-dependent pattern in domestic chickens. 相似文献
4.
张志勇 《内蒙古大学学报(人文社会科学版)》2011,(4):53-59
后国际金融危机时代的政府与市场关系必须得到明确和界定,在经济领域应坚持市场为基础和主导、政府宏观调控为辅的关系模式,但要防止经济政策被滥用到社会政策上;社会领域应坚持政府为主导,市场调节为补充的关系模式,但在其社会政策运作过程中需要引入市场机制。中国的市场经济经受住了国际金融危机的考验,后危机时代应确定政府与市场关系的中国发展模式。 相似文献
5.
This article reviews the terms and concepts that have been used for describing regulation of learning during cooperative and collaborative learning and suggests differentiating them on the basis of which parts of a regulatory feedback loop model are being shared. During cooperative and collaborative learning, not only self-regulation but also the regulation of the group process is important. This regulation might occur on both an individual level and a social level. Several modes of regulation have been identified, but the terms used for them vary tremendously—including social regulation, socially shared regulation, coregulation, and other-regulation. This article seeks to clarify the diverse terminology. To this end, we use a theoretical framework based on Winne and Hadwin's (1998) model of self-regulated learning to analyze how the different terms are used in the literature. We make and exemplify suggestions for a consistent usage of terms. 相似文献
6.
Stephanie Huffman 《TechTrends》2010,54(3):38-44
Many of the projects and assignments we have our students complete for our classes include a multimedia presentation. Why are we not teaching our students how to cite their sources for these presentations? Writing style (APA, MLA, or Chicago) does not matter. Regardless of whether it is a paper or multimedia presentation students should always cite their sources, otherwise plagiarism is occurring. This is a skill we must teach and demand that our students take responsibility for when completing multimedia presentations. This article covers a brief overview of copyright law, provides helpful resources for students and teachers, and outlines a model that can be used in citing sources in multimedia presentations. This model goes beyond the producer required credit slide to argue for the inclusion of “in product/text” citations for multimedia presentations. 相似文献
7.
The cross-lagged panel model (CLPM), a discrete-time (DT) SEM model, is frequently used to gather evidence for (reciprocal) Granger-causal relationships when lacking an experimental design. However, it is well known that CLPMs can lead to different parameter estimates depending on the time-interval of observation. Consequently, this can lead to researchers drawing conflicting conclusions regarding the sign and/or dominance of relationships. Multiple authors have suggested the use of continuous-time models to address this issue.
In this article, we demonstrate the exact circumstances under which such conflicting conclusions occur. Specifically, we show that such conflicts are only avoided in general in the case of bivariate, stable, nonoscillating, first-order systems, when comparing models with uniform time-intervals between observations. In addition, we provide a range of tools, proofs, and guidelines regarding the comparison of discrete- and continuous-time parameter estimates. 相似文献
8.
《信阳师范学院学报(哲学社会科学版)》2015,(6):32-37
情绪调节作为个体社会化的重要组成部分和适应社会的关键心理机制,受到情感研究领域的大量关注。基于Gross的情绪调节过程模型,选择注意分散和认知重评策略,借助事件相关电位技术,探索二者电生理学特征之间的差异,揭示调节策略的性别差异。得出如下结论:(1)与认知重评策略相比,注意分散发生在情绪生成过程的较早阶段。(2)男性偏向于使用认知重评策略,而女性则偏向于使用注意分散策略。(3)认知重评策略的性别差异显著,男性被试比女性被试的LPP振幅小。 相似文献
9.
Felicitas M. Brech Uwe Messer Philipp A. Rauschnabel Bjoern S. Ivens 《Journal of Marketing for HIGHER EDUCATION》2017,27(1):112-130
Although many universities use social media to interact with stakeholders, little is known about the underlying mechanisms. Drawing on theories of self-presentation and community engagement, we develop a theoretical model to explain these crucial outcome factors. We then test the model based on secondary data from 159 universities. Our findings reveal the double-edged nature of community size: universities with a strong reputation tend to have more Facebook fans, but having many Facebook fans has detrimental effects on individual fan engagement. Furthermore, the frequency of updates is a crucial factor, as too frequent and too infrequent updates lead to lower levels of fan engagement. We discuss theoretical implications for online communities and derive implications for social media managers. 相似文献
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11.
Xiao-ying Wang Zhong-hua Chen Ru-yi Zhang Sen-quan Liu Zhu Mei Ying-ying Yu Xiong Zhang Qiang Xia Yue-min Ding 《Journal of Zhejiang University. Science. B》2012,13(5):356-363
Objective
Bone morphogenetic proteins (BMPs) are known to play an important role in bone and cartilage development. Recent research has shown that BMPs may induce tumorigenesis and promote tumor to spread, but the molecular mechanisms have not been elucidated. The aim of the present study was to investigate the regulatory function of BMP-2 in the migration of COS-7 cells and the underlying mechanisms. 相似文献12.
社会性规制是政府管理社会的一个重要手段。我国正处在政府规制的改革与转型期,社会性规制理论将会对社会管理工作产生深远影响。从社会性规制的角度来看,当前加强和创新社会管理应正确处理政府与社会组织以及各相关主体之间的关系,明确各方主体在社会管理中的定位;建构和实施以权利为导向的社会政策体系;健全社会风险评估机制和应急管理体系;确立以政府为主导、社会各方共同参与的民生社会管理发展新机制;增强全社会参与社会管理的活力,进一步完善社会管理运行机制。 相似文献
13.
代正群 《湖南城市学院学报》2003,24(2):37-39
随着信息技术的迅猛发展和广泛应用，传统的公共行政范式发生了深刻的变迁。行政理念由传统的权力行政超越为服务行政；行政职能出现了收缩趋势；行政组织趋于扁平化，走向柔性化；行政决策主体大众化，决策理性提升；技术规制作为全新的规制手段被引入到对政府的规制系统中。我国作为发展中国家，在设计改革方案时，对此应予以充分考虑，同时还应关注信息技术为公共行政带来的诸多问题。 相似文献
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15.
DNA is the hereditary material in humans and almost all other organisms. It is essential for maintaining accurate transmission of genetic information. In the life cycle, DNA replication, cell division, or genome damage, including that caused by endogenous and exogenous agents, may cause DNA aberrations. Of all forms of DNA damage, DNA double-strand breaks(DSBs) are the most serious. If the repair function is defective, DNA damage may cause gene mutation, genome instability, and cell chromosome loss, which in turn can even lead to tumorigenesis. DNA damage can be repaired through multiple mechanisms. Homologous recombination(HR) and non-homologous end joining(NHEJ) are the two main repair mechanisms for DNA DSBs. Increasing amounts of evidence reveal that protein modifications play an essential role in DNA damage repair.Protein deubiquitination is a vital post-translational modification which removes ubiquitin molecules or polyubiquitinated chains from substrates in order to reverse the ubiquitination reaction. This review discusses the role of deubiquitinating enzymes(DUBs) in repairing DNA DSBs. Exploring the molecular mechanisms of DUB regulation in DSB repair will provide new insights to combat human diseases and develop novel therapeutic approaches. 相似文献
16.
Preparing for an exam entails various exam-related emotions. To ensure psychologically healthy behavior and an effective learning process, emotion regulation is highly important. In the present study, we used a dynamic multilevel modeling approach to analyse the interplay of exam-related anxiety and hope, as well as four regulation strategies over time. This study provides valuable insights into students’ emotion regulation in academic settings. Specifically, we measured students’ emotions and regulation strategies (cognitive approach, cognitive avoidance, behavioral approach, behavioral avoidance) across two weeks of measurement. In total, 217 university students answered several questionnaires via an electronic device during two different measurement periods lasting 7 days each. These measurement periods were 5 weeks (day 35–29) and one week (day 7 to 1) prior to an important exam. During their everyday life, they answered these questionnaires six times a day. We applied dynamic multilevel modeling to analyse the data. Results revealed cross-lagged relationships of exam-related emotions on regulation strategies, with the strongest cross-lagged relationship being found for hope and the cognitive approach regulation strategy. Moreover, the temporal distance to the exam affected the strength and direction of these cross-lagged relationships. This study suggests the importance of considering the mechanisms of emotion regulation on the situation level, and that strategies should be tailored to the individual situation rather than employing universal strategies. Further, the extent to which we can interpret the lagged relationships as suggestive of causal mechanisms are discussed. 相似文献
17.
低社会经济地位与儿童发展 总被引：1，自引：0，他引：1
社会经济地位是根据个体获取或控制有价值资源而对其进行的层级排名，低社会经济地位会对儿童的身体健康、认知发展、情绪适应和行为问题等产生消极影响，中介模式与调节模式两种理论对这些影响的机制进行了解释。政府和全社会都要积极行动起来，以促进低社会经济地位儿童的健康成长与发展。 相似文献
18.
Christian Geiser Michael Eid Stephen G. West Tanja Lischetzke Fridtjof W. Nussbeck 《Structural equation modeling》2013,20(3):409-436
It is well known that measurement error in observable variables induces bias in estimates in standard regression analysis and that structural equation models are a typical solution to this problem. Often, multiple indicator equations are subsumed as part of the structural equation model, allowing for consistent estimation of the relevant regression parameters. In many instances, however, embedding the measurement model into structural equation models is not possible because the model would not be identified. To correct for measurement error one has no other recourse than to provide the exact values of the variances of the measurement error terms of the model, although in practice such variances cannot be ascertained exactly, but only estimated from an independent study. The usual approach so far has been to treat the estimated values of error variances as if they were known exact population values in the subsequent structural equation modeling (SEM) analysis. In this article we show that fixing measurement error variance estimates as if they were true values can make the reported standard errors of the structural parameters of the model smaller than they should be. Inferences about the parameters of interest will be incorrect if the estimated nature of the variances is not taken into account. For general SEM, we derive an explicit expression that provides the terms to be added to the standard errors provided by the standard SEM software that treats the estimated variances as exact population values. Interestingly, we find there is a differential impact of the corrections to be added to the standard errors depending on which parameter of the model is estimated. The theoretical results are illustrated with simulations and also with empirical data on a typical SEM model. 相似文献
19.
Study on the neurotoxic effects of low-level lead exposure in rats 总被引：10，自引：0，他引：10
Objective: To investigate effects of developmental lead exposure on nitric oxide synthase (NOS) activity in different brain regions and on N-methyl-D-aspartate (NMDA) receptor mRNA expression in the hippocampus of rats. On the basis of these observations, we explored possible mechanisms by which lead exposure leads to impaired learning and memorizing abilities in children. Methods: A series of rat animal models exposed to low levels of lead during the developing period was established (drinking water containing 0.025%, 0.05% and 0.075% lead acetate). NOS activities in the hippocampus, the cerebral cortex, the cerebellum and the brain stem were determined with fluorescence measurement and levels of mRNA expression of the NMDA receptor 2A (NR2A) subunit and NMDA receptor 2B (NR2B) subunit in the rat hippocampus were measured with Retro-translation (RT-PCR). Results: There were no differences in the body weight of rat pups between any of the groups at any given time (P>0.05). The blood lead level of Pb-exposed rat pups showed a systematic pattern of change: at 14 d of age, it was lower than that at 7 d of age, then rising to the peak level at 21 d and finally falling to lower levels at 28 d. The hippocampal NOS activities of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.01). NOS activities in the cerebellum of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.001) and the NOS activity of the 0.025% group was significantly lower than that of the 0.05% and 0.075% groups on the 28th day (P<0.05). NOS activity in the cerebral cortex of the 0.075% group was significantly lower than that of the control, 0.025% and 0.05% groups on the four day spans (P<0.001). There was no significant difference of NOS activity in the brain stem between any lead-exposed group and the control group on the four day spans. In the 0.05% and the 0.075% groups, the level of NR2A mRNA expression was higher than that in the control group at 7 d and 14 d of age (P<0.05). In the 0.025% group, the level of NR2A was found to be higher than that in the control group at 7 d of age only (P<0.05). No significant differences were found for the levels of NR2B mRNA expression between any of the groups at any given time. Conclusions: NOS activity in the hippocampus, the cerebral cortex and the cerebellum are inhibited by lead exposure. The degree of the inhibitory effect depends on the time span of exposure and the lead concentration. Developmental low-level lead exposure was found to raise the level of NR2A mRNA expression in the hippocampus of rats. Developmental low-level lead exposure does not affect the level of NR2B mRNA expression in the hippocampus. 相似文献
20.
Jeffrey Liew Audrea Y. Johnson Tracy R. Smith Felix Thoemmes 《Early education and development》2013,24(4):549-573
Research Findings: Parental expressivity, child physiological regulation (indexed by respiratory sinus arrhythmia suppression), child behavioral regulation, and child adjustment outcomes were examined in 45 children (M age = 4.32 years, SD = 1.30) and their parents. With the exception of child adjustment (i.e., internalizing and externalizing problems and adaptive skills), which were assessed with parents' ratings, all variables were observed behaviorally or physiologically. A 3-path mediation path model was tested with the relations between parental expressivity and child adjustment outcomes mediated through child physiological regulation and behavioral regulation. Despite low power to detect the mediated effect, there was evidence to suggest that physiological regulation and behavioral regulation were 2 mediating mechanisms by which parental high positive/low negative expressivity may influence adaptive skills. Thus, parental expressivity may shape children's physiological regulation. And physiological regulation may be 1 mechanism by which effortful control becomes manifested as behavioral regulation that becomes apparent to others who then make evaluations about individuals' adaptive skills. Practice or Policy: The results have implications for interventions aimed at parent training or parental coaching of emotion as well as interventions aimed at enhancing children's social-emotional or behavioral regulation to improve children's adaptive skills. 相似文献