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In the context of heterogeneous catalysis, oxygen on metals and oxygen on metal oxides are often considered as two different phenomena that are little related to each other. The former is mainly in...

The experimental Bronsted–Evans–Polanyi (BEP) correlations in the field of oxidation catalysis, describing both the liquid-phase reactions on metal complexes and especially the gas-phase oxidations on metal oxides including the O2 isotopic exchange, were analyzed. It was shown that the rate of deep oxidations on metal oxides is determined by two thermodynamic parameters of a catalytic system: the heat of oxygen adsorption, QO2, and the heat of reaction, Qr, which constitute a unified BEP descriptive parameter Quni = (Qr – QO2). The correlations based on the energy of chemical bonds that are cleaved or formed in the course of reaction are more limited and less predictive.Special attention was paid to the numerical value of the Bronsted coefficient β. It was found that for all oxidations, in both the liquid and gas phases, β ≈ 0.5. Using the unified BEP descriptor Quni with β = 0.5, a universal correlation was plotted describing the rates of all reactions over all catalysts under consideration.An idea of co...

Mammalian RNA polymerase I (Pol I) complexes contain a number of associated factors, some with undefined regulatory roles in transcription. We demonstrate that casein kinase 2 (CK2) in human cells is associated specifically only with the initiation-competent Pol Ibeta isoform and not with Pol Ialpha. Chromatin immunoprecipitation analysis places CK2 at the ribosomal DNA (rDNA) promoter in vivo. Pol Ibeta-associated CK2 can phosphorylate topoisomerase IIalpha in Pol Ibeta, activator upstream binding factor (UBF), and selectivity factor 1 (SL1) subunit TAFI110. A potent and selective CK2 inhibitor, 3,8-dibromo-7-hydroxy-4-methylchromen-2-one, limits in vitro transcription to a single round, suggesting a role for CK2 in reinitiation. Phosphorylation of UBF by CK2 increases SL1-dependent stabilization of UBF at the rDNA promoter, providing a molecular mechanism for the stimulatory effect of CK2 on UBF activation of transcription. These positive effects of CK2 in Pol I transcription contrast to that wrought by CK2 phosphorylation of TAFI110, which prevents SL1 binding to rDNA, thereby abrogating the ability of SL1 to nucleate preinitiation complex (PIC) formation. Thus, CK2 has the potential to regulate Pol I transcription at multiple levels, in PIC formation, activation, and reinitiation of transcription.

The reforms that have been carried out in this country's system of education over the past ten years, and the system's orientation toward humanistic, individually oriented, and developmental educational technologies, have changed attitudes toward students who exhibit abilities out of the ordinary. Educational institutions, curricula and social programs, and civic organizations and foundations have come into being whose basic aim is the identification, teaching, and development of gifted children. In the public consciousness there has been a gradually growing awareness that it is impossible to move into the age of science-intensive technologies unless the country's intellectual potential is maintained and multiplied. It has even become fashionable, in a way, to work with talented children.