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21.
Present contribution briefly describes some historical features, which are focused back to the history of the Middle European
learning as promoted by the foundation of the Charles University in Prague 1348. Physics and its neighboring areas are mentioned
discussing some crucial scientific contributions and stressing out some prominent scholars, such as Tycho de Brahe, Johannes
Kepler, Tadeáš Hájek, Marcus Marci, Jan A. Commenius (caloric), Prokop Diviš, Bernard Bolzano, Christian Doppler, Ernst Mach,
Albert Einstein, Václav Šimerka, František Záviška, Čeněk Strouhal, Reinhold Fürst or Stanislav Škramovsky (statmograph) and
Jaroslav Heyrovsky (polarography), the latter being already the representative of modern age. 相似文献
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Dipl.‐Chem. Mario Jauker Dipl.‐Chem. Helmut Griesser Prof. Clemens Richert 《Angewandte Chemie (International ed. in English)》2015,54(48):14564-14569
How the biochemical machinery evolved from simple precursors is an open question. Here we show that ribonucleotides and amino acids condense to peptidyl RNAs in the absence of enzymes under conditions established for genetic copying. Untemplated formation of RNA strands that can encode genetic information, formation of peptidyl chains linked to RNA, and formation of the cofactors NAD+, FAD, and ATP all occur under the same conditions. In the peptidyl RNAs, the peptide chains are phosphoramidate‐linked to a ribonucleotide. Peptidyl RNAs with long peptide chains were selected from an initial pool when a lipophilic phase simulating the interior of membranes was offered, and free peptides were released upon acidification. Our results show that key molecules of genetics, catalysis, and metabolism can emerge under the same conditions, without a mineral surface, without an enzyme, and without the need for chemical pre‐activation. 相似文献
24.
汪建华 《数学的实践与认识》2017,(13):1-8
教育评估的可靠性决定了评估结果的可信性,影响着教育评估的声誉和发展.结合高校领军人才评审探讨了数学可靠性模型在教育评估中的应用,通过建立数学可靠性模型,计算评审系统的可靠性,并结合可靠性计算结果分析了影响评审系统可靠性的因素. 相似文献
25.
高校教师绩效工资管理系统的设计得益于管理科学与信息技术的有机结合,并基于高校教师的职业与人事管理特征有效实现管理自动化、信息透明化、公平效率化的设计初衷。系统通过几个主要功能模块的分工与流程,结合系统的参数设置与运算,可以自动生成教师的绩效津贴。从而实现高校有限资源的优化配置与绩效工资的合理分配,在激励教职员工爱岗敬业、自我实现的同时,实现教师个人与高校优势互补、和谐共进的多赢局面。 相似文献
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The structure of interaction plays an important role in the outcome of evolutionary games. This study investigates the evolution of stochastic strategies of the prisoner's dilemma played on structures ranging from lattices to small world networks. Strategies and payoffs are analyzed as a function of the network characteristics of the node they are playing on. Nodes with lattice‐like neighborhoods tend to perform better than the nodes modified during the rewiring process of the construction of the small‐world network. © 2007 Wiley Periodicals, Inc. Complexity 12:22–36, 2006 相似文献
28.
It is very likely that the main driving force of enzyme evolution is the requirement to improve catalytic and regulatory efficiency which results from the intrinsic performance as well as from the spatial and functional organization of enzymes in living cells.Kinetic co-operativity may occur in simple monomeric proteins if they display “slow” conformational transitions, at the cost of catalytic efficiency. Oligomeric enzymes on the other hand can be both efficient and co-operative. We speculate that the main reason for the emergence of co-operative oligomeric enzymes is the need for catalysts that are both cooperative and efficient. As it is not useful for an enzyme to respond to a change of substrate concentration in a complex kinetic way, the emergence of symmetry has its probable origin in a requirement for “functional simplicity”.In a living cell, enzyme are associated with other macromolecules and membranes. The fine tuning of their activity may also be reached through mutations of the microenvironment. Our hypothesis is that these mutations are related to the vectorial transport of molecules, to achieve the hysteresis loops of enzyme reactions generated by the coupling of reaction and diffusion, through the co-operativity brought about by electric interactions between a charged substrate and a membrane, and last but not least, through oscillations. As the physical origins of these effects are very simple and do not require complex molecular devices, it is very likely that the functional advantage generated by the spatial and functional organization of enzyme molecules within the cell have appeared in prebiotic catalysis or very early during the primeval stages of biological evolution.We shall began this paper by presenting the nature of the probable earliest catalysts in the RNA world. 相似文献
29.
Michal Demetrian 《International Journal of Theoretical Physics》2006,45(12):2297-2304
The second order Coleman–de Luccia instanton and its action in the Randall–Sundrum type II model are investigated and the comparison with the results in Einstein’s general relativity is done in the present paper.
PACS Numbers: 98.80.Cq. 相似文献
30.
K. A. Bronnikov S. A. Kononogov V. N. Melnikov 《General Relativity and Gravitation》2006,38(7):1215-1232
We discuss possible variations of the effective gravitational constant with length scale, predicted by most of alternative theories of gravity and unified models of physical interactions. After giving a brief general exposition, we review in more detail the predicted corrections to Newton’s law of gravity in diverse brane world models. We consider various configurations in 5 dimensions (flat, de Sitter and AdS branes in Einstein and Einstein–Gauss–Bonnet theories, with and without induced gravity and possible incomplete graviton localization), 5D multi-brane systems and some models in higher dimensions. A common feature of all models considered is the existence of corrections to Newton’s law at small radii comparable with the bulk characteristic length: at such radii, gravity on the brane becomes effectively multidimensional. Many models contain superlight perturbation modes, which modify gravity at large scale and may be important for astrophysics and cosmology. 相似文献