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51.
We have studied the efficiency of research in the EU by a percentile-based citation approach that analyzes the distribution of country papers among the world papers. Going up in the citation scale, the frequency of papers from efficient countries increases while the frequency from inefficient countries decreases. In the percentile-based approach, this trend, which is uniform at any citation level, is measured by the ep index that equals the Ptop 1%/Ptop 10% ratio. By using the ep index we demonstrate that EU research on fast-evolving technological topics is less efficient than the world average and that the EU is far from being able to compete with the most advanced countries. The ep index also shows that the USA is well ahead of the EU in both fast- and slow-evolving technologies, which suggests that the advantage of the USA over the EU in innovation is due to low research efficiency in the EU. In accord with some previous studies, our results show that the European Commission’s ongoing claims about the excellence of EU research are based on a wrong diagnosis. The EU must focus its research policy on the improvement of its inefficient research. Otherwise, the future of Europeans is at risk.  相似文献   
52.
The present study examined the effects of anticipated achievement feedback on students' semantic processing on the neural level, using event-related brain potentials (ERPs). Participants (N = 79) anticipated either self-referential or normative achievement feedback regarding an announced upcoming test. Additionally, their performance expectations (low vs. no expectations) were orthogonally manipulated. Subsequently, students' on-line semantic processing was assessed by measuring the N400 cloze effect, a component in the EEG signal of which the amplitude is associated with semantic processing. Within the low performance-expectation condition, no effect of anticipated feedback on semantic processing was found. Within the no-performance-expectation condition, participants anticipating self-referential feedback showed a more widely distributed N400 cloze effect than participants anticipating normative feedback. The results confirmed the hypothesis that the mere expectation of a particular type of feedback can affect students' semantic processes.  相似文献   
53.
The world has been turned upside down by a global health emergency caused by the Covid-19. Given the high contagiousness of the virus and the need to contain its spread, social distancing rules, self-isolation policies, and geographical lockdowns have been enforced globally. Over the pandemic emergency the majority of the planned in-person meetings and congresses of national and international anatomical societies have been postponed or canceled. It is unclear what the future holds, but times of crisis often present possibilities for re-thinking old ways to achieve a more critical approach. It has become increasingly clear that traditional in-person congress formats of scientific societies need to be reevaluated. Over the past year and a half, two types of congressional modalities have been trialed to address the challenge of the pandemic as far as scientific meetings are concerned: the fully virtual congress, in which case the conference program is live streamed to all of the attendees, and the hybrid congress, in which case some of the attendees physically participate at the congress's venue while others interact via a virtual platform. The current study set out to investigate the technical difficulties, social challenges, costs and sustainability, logistics and management issues linked to holding various types of congresses in the post-Covid world. Anatomical societies throughout the world are actively striving to reshape their response to the current global emergency and to uncover new types of conference modalities in the effort to keep scientific exchange alive and flourishing in the post-Covid era.  相似文献   
54.
In fall 2016, the Columbia-Cornell collaboration in the area of Slavic & East European resource coordination and sharing celebrated its sixth year. The author reviews particulars of the development, implementation, and function of this program as well as some of the challenges that face such cross-institutional efforts.  相似文献   
55.
We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterized by an assemblage of garnet, orthopyroxene, spinel, cordierite, biotite, plagioclase and quartz. Symplectites of orthopyroxene and spinel, and orthopyroxene and cordierite indicate decompression under UHT conditions. Mineral chemistry shows that the or-thopyroxenes have high XMg and A12O3 contents (up to 9.23 wt%). Biotites are enriched in TiO2 and XMg and are stable under granulite facies conditions. The garnet and quartz from the rock carry monophase fluid inclusions which show peak melting temperatures of around -56.7℃, indicating a pure CO2 species being presented during the ultrahigh-T metamorphism in the Altay orogenic belt. The inclusions homogenize into a liquid phase at temperatures around 15.3-23.8℃ translating into CO2 densities of the order of 0.86-0.88 g/cm3. Based on prelim  相似文献   
56.
Classificationofaircleanlinessinanykindofclean roomsandcleanzoneswillbeaccomplishedintermsofconcentrationofairborneparticles .Alightdiscreteair borneparticlecounter (hereafterreferringtoasAPC)isusedtodeterminetheconcentrationofairborneparticlesequaltoandlargerthanthespecifiedsizesatdesignatedsamplinglocation[1,2 ] .Inthepracticalmeasurementofparticleconcentrationincleanrooms,itisfoundthetest ingresultsofparticlenumberinthesameareacountedbydifferentparticlecountersarequitedifferentanduptoanord…  相似文献   
57.
Architecture singularity of a parallel mechanism with five degrees of freedom (DOF) is analyzed. Such mechanism consists of a movable platform connected to the base by five active limbs. Four of them are identical 6-DOF limbs and the last one has the same DOF as the specified DOF of the movable platform. Based on the kinematics analysis, two categories of architecture singularities for such mechanism are proposed. Then the sufficient condition for each singularity is researched. Results show that the mechanism is singular when it employs each category of the proposed architecture, provided that it satisfies the corresponding sufficient condition. It can be concluded that the proposed two categories of architecture singularities should be avoided with the following dimensional synthesis of such mechanism.  相似文献   
58.
阐述了三层C/S体系结构的优点,Tuxedo中间件的主要功能和特点.介绍了在Linux操作系统下基于Tuxedo的三层C/S体系结构的报刊发行信息系统的设计与实现.  相似文献   
59.
This paper examines the context and impact of the industrial materials and processes of the mid-twentieth century on Donald Judd's works, focusing on galvanized steel, cellulose nitrate paints, anodizing, and the RAL color matching system. Exploration of the industrial materials and methods Judd utilized provides a greater understanding of his processes, choices, and ultimately his art, its care, and legacy.  相似文献   
60.
5-氨基四唑及其衍生物的合成和应用综述   总被引:1,自引:0,他引:1  
文章综述了5-氨基四唑及其4种衍生物高氯酸.四氨.双(5-硝基四唑)合钴(Ⅲ)(BNCP)、3,6-双(l-氢-l,2,3,4-四唑-5-氨基)-l,2,4,5-四嗪(BTATz)、5-氨基四唑的Schiff碱、α-(5-四唑基)氨基烃基膦酸酯的合成、性质与应用.  相似文献   
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