Two−photon Processes in Organometallic Molecules and Clusters: T−T Absorption of Group IV Metal Complexes

Triplet – triplet absorption of d0 metal complexes was for the first time revealed and studied by means of pulse photolysis and electron-exchange (Dexter) resonant energy transfer energy transfer. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3539

Two-loop corrections to the decay rate of parapositronium

Order $\alpha^2$ corrections to the decay rate of parapositronium are calculated. A QED scattering calculation of the amplitude for electron-positron annihilation into two photons at threshold is combined with the technique of effective field theory to determine an NRQED Hamiltonian, which is then used in a bound state calculation to determine the decay rate. Our result for the two-loop correction is $5.1243(33)$ in units of $(\alpha/\pi)^2$ times the lowest order rate. This is consistent with but more precise than the result $5.1(3)$ of a previous calculation.Comment: 26 pages, 7 figure

Менингококковые вакцины: от капсульных полисахаридов до протеаз

Microbial capsular polysaccharides for many years provided a highly practical public health vaccines for preventing meningococcal, pneumococcal and Haemophilus influenza infection, and typhoid fever. Their application in the form of conjugates with protein carriers eliminate the gap in protection against these infections in children under one year. Extremely promising turned out offered us a new generation of vaccines, which have synthetic peptides conjugated to a meningococcal polysaccharide. Thus, new approaches to the solution of the problem of meningococcal disease vaccination serogroup B were open. In recent years, Russian researchers first suggested to use IgA1 protease (one of the major virulence factors of microbes and almost identical for mentioned below infections) for prevention of such diseases as meningococcal of all serogroups, pneumococcus and hemophilia infections. Patented processes for producing of the vaccine define domestic priority of its production and use.Микробные капсульные полисахариды на протяжении многих лет обеспечивали практическое здравоохранение высокоэффективными вакцинами для профилактики менингококковых, пневмококковых, гемофильных инфекций и брюшного тифа. А их применение в виде конъюгатов с белковыми носителями ликвидировало пробел при защите от этих инфекций детей в возрасте до одного года. Необычайно перспективным оказалось предложенное нами новое поколение вакцин, где уже синтетические пептиды конъюгировались с полисахаридами менингококков. Таким образом, были открыты подходы к решению проблемы вакцинопрофилактики менингококковой инфекции серогруппы В. В последние годы отечественные исследователи впервые предложили использовать для профилактики менингококковых инфекций всех серогрупп, а также инфекций, обусловленных пневмококками и гемофилами, один из главных факторов вирулентности этих микробов — IgA1 протеазу, практически идентичную для всей указанной группы инфекций. Запатентованные способы получения этой вакцины определяют отечественный приоритет ее производства и применения

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

Measurement of the ttbar production cross section and top quark mass extraction using dilepton events in ppbar collisions

We present a measurement of the top quark pair production cross section in ppbar collisions at \sqrt{s}=1.96 TeV using approximately 1 fb^{-1} of data collected with the D0 detector. We consider decay channels containing two high pt charged leptons where one lepton is identified as an electron or a muon while the other lepton can be an electron, a muon or a hadronically decaying tau lepton. For a mass of the top quark of 170 GeV, the measured cross section is 7.5 +1.0-1.0 (stat) +0.7-0.6 (syst) +0.6-0.5 (lumi) pb. Using lepton+tau events only, we measure: \sigma_ttbar \times B(ttbar to ltau bbbar) = 0.13 +0.09-0.08 (stat) +0.06-0.06 (syst) +0.02-0.02 (lumi) pb. Comparing the measured cross section as a function of the mass of the top quark with a partial next-to-next-to leading order Quantum Chromodynamics theoretical prediction, we extract a mass of the top quark of 171.5 +9.9-8.8 GeV, in agreement with direct measurements.Comment: published in Phys. Lett. B, 10 pages, 7 figure

Measurement of the mass difference between top quark and antiquark in pp collisions at root s=8 TeV

Peer reviewe

Search for supersymmetry in events with a photon, a lepton, and missing transverse momentum in pp collisions at root s=8 TeV

Peer reviewe

Nuclear oncoprotein prothymosin alpha is a partner of Keap1: implications for expression of oxidative stress-protecting genes

Animal cells counteract oxidative stress and electrophilic attack through coordinated expression of a set of detoxifying and antioxidant enzyme genes mediated by transcription factor Nrf2. In unstressed cells, Nrf2 appears to be sequestered in the cytoplasm via association with an inhibitor protein, Keap1. Here, by using the yeast two-hybrid screen, human Keap1 has been identified as a partner of the nuclear protein prothymosin α. The in vivo and in vitro data indicated that the prothymosin α-Keap1 interaction is direct, highly specific, and functionally relevant. Furthermore, we showed that Keap1 is a nuclear-cytoplasmic shuttling protein equipped with a nuclear export signal that is important for its inhibitory action. Prothymosin α was able to liberate Nrf2 from the Nrf2-Keap1 inhibitory complex in vitro through competition with Nrf2 for binding to the same domain of Keap1. In vivo, the level of Nrf2-dependent transcription was correlated with the intracellular level of prothymosin α by using prothymosin α overproduction and mRNA interference approaches. Our data attribute to prothymosin α the role of intranuclear dissociator of the Nrf2-Keap1 complex, thus revealing a novel function for prothymosin α and adding a new dimension to the molecular mechanisms underlying expression of oxidative stress-protecting genes

Isolation and determination of the activity of IgA1 protease from Neisseria meningitidis

A method of the isolation and purification of IgA1 protease from a culture of Neisseria meningitidis serogroup A has been developed. Three inactivated intermediates of the production of the meningococcal vaccine, a culture liquid, as well as a supernatant and precipitate obtained by the precipitation of bacterial cells by cetavlon, served as a starting material. The purity of IgA1 protease was determined by SDS-PAGE. An immunoenzyme assay for determining the IgA1 protease activity has been developed. The yield of the enzyme with a specific activity of 0.5 to 4 million units/mg from 103 g of the cetavlon precipitate (40 l of culture liquid) was about 600 μg. It was shown that IgA1 protease isolated from serogroup A meningococcus is capable of protecting experimental animals (mice) infected with meningococcus of serogroup B. © 2010 Pleiades Publishing, Ltd