401 research outputs found

    A Study of the Use of Modified Collagen of Freshwater Fish as a Material for Personal Care Products

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    The work is devoted to the use of collagen materials produced on the basis of connective tissues of hydrobionts. Their characteristics as potential means of personal hygiene and wound healing are investigated. The results of studies of physical and chemical characteristics of collagen materials from freshwater fish with a modified structure obtained in this paper indicate the prospects of their use as an absorbent layer of personal hygiene products, due to the high moisture absorption capacity, which is an order of magnitude higher than the moisture capacity of untreated collagen and higher moisture capacity of superadsorbing polymers required for use in personal hygiene products. The resulting material meets the requirements of sanitary and epidemiological safety, allergenic action on the skin, as can be concluded from the results of tests on animals, it does not. This material accelerates reparative processes to the same extent as collagen used in standard hemostatic sponges with the simplicity of its production technology, low cost, and availability of raw materials

    The role of oxidized non-coding RNAs of the epigenome in the development of human diseases (literature review)

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    The attention of scientists to the role of the epigenome in the development of human diseases is associated with the discovery of new non-coding RNA molecules of the epigenome that affect gene expression with changes in protein function and the development of diseases. The study analyzed current scientific data on the effect of oxidative stress induced by cadmium on the regulatory mechanisms of the epigenome, resulting in the development of pathological changes in the body. The results of the study showed that cadmium manifests its toxicity by oxidizing micro RNAs and long RNAs that regulate gene expression without changing DNA/histone complexes. It has been shown that epigenetic disorders under the influence of cadmium-induced oxidative stress can be transmitted to offspring without changing the genotype, and these aberrant changes in non-coding RNA expression patterns are associated with aging, cancer, neurodegenerative, cardiovascular diseases, etc. Circulating micro RNAs that are sensitive to oxidative stress are reported to be potential biomarkers of cardiovascular diseases, including myocardial infarction, hyper­trophy, ischemia/reperfusion, and heart failure. Many studies are aimed at using microRNAs for therapeutic purposes. The complete expression profile of microRNAs in human atherosclerotic plaques was studied, and the mechanisms affecting their formation were identified. Specific microRNAs and reactive oxygen species were identified as potential biomarkers in human malignancies, which expands the possibilities of their use as therapeutic targets. Unlike micro RNAs, the expression of long RNAs has tissue and species specificity, making them important candidates for specific disease markers. The role of these RNAs in carcinogenesis is being actively studied. A large number of them are disrupted at various types of cancer and may play an im­portant role in the onset, metastasis, and therapeutic response of cancer. Thus, oxidative stress induced by cad­mium affects non-coding RNAs, which disrupts the regulatory mechanisms of the epigenome and affects the deve­lopment of cardiovascular, oncological, pulmonary and other human diseases. The search for the impact of non-coding RNAs on the epigenome is constantly growing and has great scientific and practical prospects in medicine

    Vector meson production and nucleon resonance analysis in a coupled-channel approach for energies m_N < sqrt(s) < 2 GeV II: photon-induced results

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    We present a nucleon resonance analysis by simultaneously considering all pion- and photon-induced experimental data on the final states gamma N, pi N, 2 pi N, eta N, K Lambda, K Sigma, and omega N for energies from the nucleon mass up to sqrt(s) = 2 GeV. In this analysis we find strong evidence for the resonances P_{31}(1750), P_{13}(1900), P_{33}(1920), and D_{13}(1950). The omega N production mechanism is dominated by large P_{11}(1710) and P_{13}(1900) contributions. In this second part we present the results on the photoproduction reactions and the electromagnetic properties of the resonances. The inclusion of all important final states up to sqrt(s) = 2 GeV allows for estimates on the importance of the individual states for the GDH sum rule.Comment: 41 pages, 26 figures, discussion extended, typos corrected, references updated, to appear in Phys. Rev.

    Electric current circuits in astrophysics

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    Cosmic magnetic structures have in common that they are anchored in a dynamo, that an external driver converts kinetic energy into internal magnetic energy, that this magnetic energy is transported as Poynting fl ux across the magnetically dominated structure, and that the magnetic energy is released in the form of particle acceleration, heating, bulk motion, MHD waves, and radiation. The investigation of the electric current system is particularly illuminating as to the course of events and the physics involved. We demonstrate this for the radio pulsar wind, the solar flare, and terrestrial magnetic storms

    Limit on Tau Neutrino Mass from τππ+ππ0ντ\tau^{-}\to \pi^{-}\pi^{+}\pi^{-}\pi^{0}\nu_{\tau}

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    From a data sample of 29058 τ±π±π+ππ0ντ\tau^\pm\to\pi^\pm\pi^+\pi^-\pi^0\nu_\tau decays observed in the CLEO detector we derive a 95% confidence upper limit on the tau neutrino mass of 28 MeV.Comment: 17 pages postscript, also available through http://w4.lns.cornell.edu/public/CLN

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

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    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

    Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV

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    A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross section of the standard model Higgs boson decaying to two photons. The expected exclusion limit at 95% confidence level is between 1.4 and 2.4 times the standard model cross section in the mass range between 110 and 150 GeV. The analysis of the data excludes, at 95% confidence level, the standard model Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The largest excess of events above the expected standard model background is observed for a Higgs boson mass hypothesis of 124 GeV with a local significance of 3.1 sigma. The global significance of observing an excess with a local significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is estimated to be 1.8 sigma. More data are required to ascertain the origin of this excess.Comment: Submitted to Physics Letters

    Measurement of the Lambda(b) cross section and the anti-Lambda(b) to Lambda(b) ratio with Lambda(b) to J/Psi Lambda decays in pp collisions at sqrt(s) = 7 TeV

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    The Lambda(b) differential production cross section and the cross section ratio anti-Lambda(b)/Lambda(b) are measured as functions of transverse momentum pt(Lambda(b)) and rapidity abs(y(Lambda(b))) in pp collisions at sqrt(s) = 7 TeV using data collected by the CMS experiment at the LHC. The measurements are based on Lambda(b) decays reconstructed in the exclusive final state J/Psi Lambda, with the subsequent decays J/Psi to an opposite-sign muon pair and Lambda to proton pion, using a data sample corresponding to an integrated luminosity of 1.9 inverse femtobarns. The product of the cross section times the branching ratio for Lambda(b) to J/Psi Lambda versus pt(Lambda(b)) falls faster than that of b mesons. The measured value of the cross section times the branching ratio for pt(Lambda(b)) > 10 GeV and abs(y(Lambda(b))) < 2.0 is 1.06 +/- 0.06 +/- 0.12 nb, and the integrated cross section ratio for anti-Lambda(b)/Lambda(b) is 1.02 +/- 0.07 +/- 0.09, where the uncertainties are statistical and systematic, respectively.Comment: Submitted to Physics Letters

    Search for new physics in events with opposite-sign leptons, jets, and missing transverse energy in pp collisions at sqrt(s) = 7 TeV

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    A search is presented for physics beyond the standard model (BSM) in final states with a pair of opposite-sign isolated leptons accompanied by jets and missing transverse energy. The search uses LHC data recorded at a center-of-mass energy sqrt(s) = 7 TeV with the CMS detector, corresponding to an integrated luminosity of approximately 5 inverse femtobarns. Two complementary search strategies are employed. The first probes models with a specific dilepton production mechanism that leads to a characteristic kinematic edge in the dilepton mass distribution. The second strategy probes models of dilepton production with heavy, colored objects that decay to final states including invisible particles, leading to very large hadronic activity and missing transverse energy. No evidence for an event yield in excess of the standard model expectations is found. Upper limits on the BSM contributions to the signal regions are deduced from the results, which are used to exclude a region of the parameter space of the constrained minimal supersymmetric extension of the standard model. Additional information related to detector efficiencies and response is provided to allow testing specific models of BSM physics not considered in this paper.Comment: Replaced with published version. Added journal reference and DO

    Measurement of isolated photon production in pp and PbPb collisions at sqrt(sNN) = 2.76 TeV

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    Isolated photon production is measured in proton-proton and lead-lead collisions at nucleon-nucleon centre-of-mass energies of 2.76 TeV in the pseudorapidity range |eta|<1.44 and transverse energies ET between 20 and 80 GeV with the CMS detector at the LHC. The measured ET spectra are found to be in good agreement with next-to-leading-order perturbative QCD predictions. The ratio of PbPb to pp isolated photon ET-differential yields, scaled by the number of incoherent nucleon-nucleon collisions, is consistent with unity for all PbPb reaction centralities.Comment: Submitted to Physics Letters
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