B_s(d) - bar B_s(d) mixing constraints on flavor changing decays of t and b quarks

We study those dimension 6 effective operators which generate flavor-changing quark-gluon transitions of the third generation quarks, with t -> g + u(c) and b -> g + d(s), and which could be of interest for LHC experiments. We analyze the contribution of these operators to B_s(d) - bar B_s(d) mixing and derive limits on the corresponding effective couplings from the existing experimental data. The Standard Model gauge invariance relates these couplings to the couplings controlling t -> g + u(c). On this basis we derive upper limits for the branching ratios of these processes. We further show that forthcoming LHC experiments might be able to probe the studied operators and the physics beyond the Standard Model related to them.Comment: 6 pages, 1 figur

X(3872) as a hadronic molecule and its decays to charmonium states and pions

The X(3872) with quantum numbers J(PC) = 1(++) is considered as a composite hadronic state comprised of the dominant molecular D(0) D*(0) component and other hadronic pairs - D(+-) D*(-+), Jpsi omega and Jpsi rho. Applying the compositeness condition we constrain the couplings of the X(3872) to its constituents. We calculate two- and three-body hadronic decays of the X(3872) to charmonium states chi(cJ) and pions using a phenomenological Lagrangian approach. Next using the estimated X-Jpsi-omega and and X-Jpsi-rho couplings we calculate the widths of X(3872) to Jpsi + h, where h = pi(+) pi(-), pi(+) pi(-) pi(0), pi(0) gamma and gamma. The obtained results for the decay pattern of the X(3872) in a molecular interpretation could be useful for running and planned experiments.Comment: 12 pages, 3 figures, accepted for publication in Phys. Rev.

Components of Natural Photosynthetic Apparatus in Solar Cells

Oxygenic photosynthesis is a process of light energy conversion into the chemical energy using water and carbon dioxide. The efficiency of energy conversion in the primary processes of photosynthesis is close to 100%. Therefore, for many years, photosynthesis has attracted the attention of researchers as the most efficient and eco-friendly pathway of solar energy conversion for alternative energy systems. The recent advances in the design of optimal solar cells include the creation of converters, in which thylakoid membranes, photosystems and whole cells of cyanobacteria immobilized on nanostructured electrode are used. As the mechanism of solar energy conversion in photosynthesis is sustainable and environmentally safe, it has a great potential as an example of renewable energy device. Application of pigments such as Chl f and Chl d will extend the spectral diapason of light transforming systems allow to absorb the far-red and near infra-red photons of the spectrum (in the range 700-750 nm). This article presents the recent achievements and challenges in the area of solar cells based on photosynthetic systems

Classical and quantum cross-section for black hole production in particle collisions

We suggest a simple model to study the problem of the black hole production in particle collisions. The cross-section for the classical and quantum production is analysed within this model. In particular, the possibility to form a black hole in collision of low energy particles (or at large impact parameter) via the quantum tunneling mechanism is pointed out. It is found that, in this model, the geometric cross-section gives a good estimate for the production at low and high energies. We also reconsider the arguments in favor of exponential suppression for the production of trans-Planckian black hole and conclude that no such suppression in fact appears. Analyzing the probability for the black hole production we point out on the importance of the backreaction and reevaluate the contribution of the black hole formed in gravitational collapse to the Euclidean path integral.Comment: 14 pages; v2: comment on gravitational radiation corrected, lower energy regime more emphasize

Deuterons and space-momentum correlations in high energy nuclear collisions

Using a microscopic transport model together with a coalescence after-burner, we study the formation of deuterons in Au + Au central collisions at s = 200 AGeV . It is found that the deuteron transverse momentum distributions are strongly a ected by the nucleon space-momentum correlations, at the moment of freeze-out, which are mostly determined by the number of rescatterings. This feature is useful for studying collision dynamics at ultrarelativistic energies

Applicability of energy storage units to electric transport

The paper analyzes the possibility for replacement hydrocarbon fuels by energy storage devices in transport. The technical characteristics of the modern batteries and ultracapacitors are presented, their specific parameters are estimated. Energy and power requirements for various driving styles of the vehicles are estimated. The determination of requirements for energy storage devices and the evaluation of applicability of energy storage units are demonstrated in the article

От тройной к пятеричной спирали: эволюция методологии развития инновационной экономики

The presented paper deals with an approach to the evolution of methodology of economy innovative development from the standpoint of analyzing the interaction of its actors – from a Triple to a Penta Helix. The article proposes the provisions for such a methodology based on expanding the range of actors of innovative development as public interests shift from the emergence of a free enterprise economy to a socially oriented knowledge economy and further to a balanced and environmentally friendly production and consumption. A special role in the presented approach is given to the analysis of the place of universities in the fivefold spiral of innovative transformation of economy – as a creator of sustainable development values. The authors proved that the Penta Helixis the result of the evolution of the Quadruple Helix in the conditions of increasing the values of sustainable development. In turn, the core of the QuadrupleHelix– the Triple Helix– acts as the core in the Penta Helix. The article highlights three varieties of the TripleHelix model that is dominant today in industrialized countries, shows their connection with the peculiarities of the innovative development of the Russian economy. On this basis, it was concluded that the progress in building the Penta Helix of innovative development in Russia depends on the emergence of new actors – the subjects of the green economy and civil society, and the full expression of their economic interestsВ представленной статье рассматривается подход к эволюции методологии развития инновационной экономики с позиций анализа взаимодействия ее акторов – от тройной к пятеричной спирали. В статье предлагаются положения методологии, основанной на расширении круга акторов инновационного развития по мере смещения общественного интереса от становления экономики свободного предпринимательства к социально ориентированной экономике знаний и далее – к сбалансированному и экологически безопасному производству и потреблению. Особая роль в представленном подходе отводится анализу места университетов в пятеричной инновационной трансформации экономики – как создателей ценностей устойчивого развития. Авторы доказали, что пятеричная спираль является результатом эволюции четверной спирали инноваций в условиях повышения роли ценностей устойчивого развития. В свою очередь, ядро четверной спирали – тройная спираль – действует и как ядро пятеричной спирали. В статье выделены три разновидности модели тройной спирали, доминирующей сегодня в промышленно развитых странах, показана их связь с особенностями инновационного развития российской экономики. На этом основании сделан вывод, что прогресс в формировании пятеричной спирали инновационного развития в России зависит от появления новых акторов – субъектов зеленой экономики и гражданского общества, полноты выражения их экономических интересо

Melting of the vortex-solid in irradiated Bi2Sr2CaCu2O8+δ single crystals in tilted magnetic fields

We study the boundary between the vortex-solid and the vortex-liquid phases in the Hc–Hab plane, for irradiated Bi2Sr2CaCu2O8+δ single crystals, by measuring the ac-local magnetic permeability in tilted magnetic fields. For high temperatures and at the phase boundary, we find that the c-axis magnetic field component Hctrans decreases linearly when increasing the in-plane magnetic field Hab, surprisingly in a wider angular range than in pristine samples. Strikingly, at lower temperatures, this linear decrease of Hctrans(Hab) transforms to a concave, hyperbolic-like, curve that differs even more strongly from the usual Ginzburg–Landau (GL) elliptical phase boundary. We also propose a theoretical approach to solve this puzzle.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49054/2/njp6_10_226.pd

Enzymatic Activities and DNA Substrate Specificity of Mycobacterium tuberculosis DNA Helicase XPB

XPB, also known as ERCC3 and RAD25, is a 3′→5′ DNA repair helicase belonging to the superfamily 2 of helicases. XPB is an essential core subunit of the eukaryotic basal transcription factor complex TFIIH. It has two well-established functions: in the context of damaged DNA, XPB facilitates nucleotide excision repair by unwinding double stranded DNA (dsDNA) surrounding a DNA lesion; while in the context of actively transcribing genes, XPB facilitates initiation of RNA polymerase II transcription at gene promoters. Human and other eukaryotic XPB homologs are relatively well characterized compared to conserved homologs found in mycobacteria and archaea. However, more insight into the function of bacterial helicases is central to understanding the mechanism of DNA metabolism and pathogenesis in general. Here, we characterized Mycobacterium tuberculosis XPB (Mtb XPB), a 3′→5′ DNA helicase with DNA-dependent ATPase activity. Mtb XPB efficiently catalyzed DNA unwinding in the presence of significant excess of enzyme. The unwinding activity was fueled by ATP or dATP in the presence of Mg2+/Mn2+. Consistent with the 3′→5′ polarity of this bacterial XPB helicase, the enzyme required a DNA substrate with a 3′ overhang of 15 nucleotides or more. Although Mtb XPB efficiently unwound DNA model substrates with a 3′ DNA tail, it was not active on substrates containing a 3′ RNA tail. We also found that Mtb XPB efficiently catalyzed ATP-independent annealing of complementary DNA strands. These observations significantly enhance our understanding of the biological roles of Mtb XPB