388 results match your criteria: "Petersburg Nuclear Physics Institute of NRC "Kurchatov Institute"[Affiliation]"

Article Synopsis
  • The study examines charged particle production in proton-lead and proton-proton collisions at a center-of-mass energy of 5 TeV, focusing on how it varies with pseudorapidity and transverse momentum.
  • It finds that charged particle production is suppressed in proton-lead collisions compared to proton-proton in the forward region, while there's an increase in the backward region for higher transverse momentum values.
  • These findings provide valuable insights into nuclear parton distribution functions (PDFs) and saturation models, especially at low parton momentum fractions down to 10^{-6}.
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Parkinson's disease (PD) is a neurodegenerative disease characterised by the formation of Lewy bodies and progressive loss of dopaminergic (DA) neurons in the substantia nigra. Lewy bodies mainly consist of α-synuclein, which plays a critical role in the pathophysiology of PD. The α-synuclein is encoded by the gene and is the first identified gene associated with hereditary PD.

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A search for low-mass dilepton resonances in Higgs boson decays is conducted in the four-lepton final state. The decay is assumed to proceed via a pair of beyond the standard model particles, or one such particle and a boson. The search uses proton-proton collision data collected with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of 137 , at a center-of-mass energy .

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Neuroepigenetic Mechanisms of Action of Ultrashort Peptides in Alzheimer's Disease.

Int J Mol Sci

April 2022

Department of Molecular Radiation Biophysics, Petersburg Nuclear Physics Institute Named after B.P. Konstantinov, NRC "Kurchatov Institute", 188300 Gatchina, Russia.

Epigenetic regulation of gene expression is necessary for maintaining higher-order cognitive functions (learning and memory). The current understanding of the role of epigenetics in the mechanism of Alzheimer's disease (AD) is focused on DNA methylation, chromatin remodeling, histone modifications, and regulation of non-coding RNAs. The pathogenetic links of this disease are the misfolding and aggregation of tau protein and amyloid peptides, mitochondrial dysfunction, oxidative stress, impaired energy metabolism, destruction of the blood-brain barrier, and neuroinflammation, all of which lead to impaired synaptic plasticity and memory loss.

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Ribosomal protein S18 acetyltransferase RimI is responsible for the acetylation of elongation factor Tu.

J Biol Chem

May 2022

Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia; Center of Life Sciences, Skolkovo Institute for Science and Technology, Moscow, Russia; Department of RNA Structure and Functions, A.N. Belozersky Institute of Physico-Chemical Biology, Moscow, Russia; Institute of Functional Genomics, Lomonosov Moscow State University, Moscow, Russia. Electronic address:

N-terminal acetylation is widespread in the eukaryotic proteome but in bacteria is restricted to a small number of proteins mainly involved in translation. It was long known that elongation factor Tu (EF-Tu) is N-terminally acetylated, whereas the enzyme responsible for this process was unclear. Here, we report that RimI acetyltransferase, known to modify ribosomal protein S18, is likewise responsible for N-acetylation of the EF-Tu.

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The spectra measurements of charged hadrons produced in the shower of a parton originating in the same hard scattering with a leptonically decaying Z boson are reported in lead-lead nuclei (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Both Pb-Pb and pp data sets are recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 1.

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Nanomechanical characterization of exosomes and concomitant nanoparticles from blood plasma by PeakForce AFM in liquid.

Biochim Biophys Acta Gen Subj

July 2022

Department of Medical and Biological Physics, Gomel State Medical University, 5, Lange St., 246000 Gomel, Belarus; Institute of Radiobiology of NAS of Belarus, 4, Fedyuninskogo St., 246007 Gomel, Belarus.

Background: To date, EVs characterization techniques are extremely diverse. The contribution of AFM, in particular, is often confined to size distribution. While AFM provides a unique possibility to carry out measurements in situ, nanomechanical characterization of EVs is still missing.

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Article Synopsis
  • This article discusses the analysis of groomed jet substructure in proton-proton (pp) and lead-lead (Pb-Pb) collisions using the ALICE detector at a collision energy of 5.02 TeV.
  • The study employs a soft drop grooming algorithm to isolate hard parton splittings and measures the groomed jet momentum splitting fraction and radius, revealing distinct behavior in jet structure under different collision conditions.
  • Notably, a narrowing of the groomed jet radius distribution in Pb-Pb collisions suggests changes in jet angular structure due to quark-gluon plasma, while no significant differences are observed in momentum splitting fractions, contributing valuable insights into jet energy-loss mechanisms.
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Article Synopsis
  • - The Borexino detector at Laboratori Nazionali del Gran Sasso successfully measured sub-MeV solar neutrinos using Cherenkov radiation and a technique linking photon hits to the Sun's position.
  • - In the energy range of 0.54 to 0.74 MeV, they detected 10,887 solar neutrinos from a total of 19,904 events, indicating a neutrino interaction rate consistent with standard solar model predictions.
  • - This groundbreaking measurement showcases the use of directional Cherenkov information in liquid scintillator detectors, paving the way for future hybrid methods that utilize both Cherenkov and scintillation signals in neutrino research.
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A search for dark matter in the form of strongly interacting massive particles (SIMPs) using the CMS detector at the LHC is presented. The SIMPs would be produced in pairs that manifest themselves as pairs of jets without tracks. The energy fraction of jets carried by charged particles is used as a key discriminator to suppress efficiently the large multijet background, and the remaining background is estimated directly from data.

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Article Synopsis
  • * Data was collected using the LHCb detector with a total of 6 fb^{-1} at a center-of-mass energy of 13 TeV.
  • * An increase in the fraction of charm jets is noted at higher rapidity levels of the Z boson, suggesting the presence of an intrinsic charm component within the proton.
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Measurements of the inclusive and differential fiducial cross sections of the Higgs boson are presented, using the τ lepton decay channel. The differential cross sections are measured as functions of the Higgs boson transverse momentum, jet multiplicity, and transverse momentum of the leading jet in the event, if any. The analysis is performed using proton-proton collision data collected with the CMS detector at the LHC at a center-of-mass energy of 13  TeV and corresponding to an integrated luminosity of 138  fb^{-1}.

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A search for new long-lived particles decaying to leptons using proton-proton collision data produced by the CERN LHC at is presented. Events are selected with two leptons (an electron and a muon, two electrons, or two muons) that both have transverse impact parameter values between 0.01 and 10 and are not required to form a common vertex.

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An amplitude analysis of flavor-untagged B_{s}^{0}→J/ψpp[over ¯] decays is performed using a sample of 797±31 decays reconstructed with the LHCb detector. The data, collected in proton-proton collisions between 2011 and 2018, correspond to an integrated luminosity of 9  fb^{-1}. Evidence for a new structure in the J/ψp and J/ψp[over ¯] systems with a mass of 4337_{-4}^{+7} _{-2}^{+2}  MeV and a width of 29_{-12}^{+26} _{-14}^{+14}  MeV is found, where the first uncertainty is statistical and the second systematic, with a significance in the range of 3.

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With the establishment of the CRISPR-Cas9 molecular tool as a DNA editing system in 2012, the handling of gene editing experiments was strongly facilitated pushing reverse genetics approaches forward in many organisms. These new gene editing technologies also drastically increased the possibilities for design-driven synthetic biology. Here, we describe a protocol for gene editing in the green algae Chlamydomonas reinhardtii using preassembled CRISPR-Cas9 ribonucleoproteins.

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Analysis of Neutral B-Meson Decays into Two Muons.

Phys Rev Lett

January 2022

Department of Physics and Astronomy, University of Manchester, Manchester, United Kingdom.

Branching fraction and effective lifetime measurements of the rare decay B_{s}^{0}→μ^{+}μ^{-} and searches for the decays B^{0}→μ^{+}μ^{-} and B_{s}^{0}→μ^{+}μ^{-}γ are reported using proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a luminosity of 9  fb^{-1}. The branching fraction B(B_{s}^{0}→μ^{+}μ^{-})=(3.09_{-0.

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The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) production is studied in lead-lead (Pb-Pb) collisions at a center-of-mass energy of sqrt[s_{NN}]=5.02  TeV per nucleon pair, using the decay chain X(3872)→J/ψπ^{+}π^{-}→μ^{+}μ^{-}π^{+}π^{-}.

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The p_{T}-differential production cross sections of prompt D^{0}, Λ_{c}^{+}, and Σ_{c}^{0,++}(2455) charmed hadrons are measured at midrapidity (|y|<0.5) in pp collisions at sqrt[s]=13  TeV. This is the first measurement of Σ_{c}^{0,++} production in hadronic collisions.

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The p_{T}-differential cross sections of prompt charm-strange baryons Ξ_{c}^{0} and Ξ_{c}^{+} were measured at midrapidity (|y|<0.5) in proton-proton (pp) collisions at a center-of-mass energy sqrt[s]=13  TeV with the ALICE detector at the LHC. The Ξ_{c}^{0} baryon was reconstructed via both the semileptonic decay (Ξ^{-}e^{+}ν_{e}) and the hadronic decay (Ξ^{-}π^{+}) channels.

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Bifractal structure of chromatin in rat lymphocyte nuclei.

Phys Rev E

December 2021

Petersburg Nuclear Physics Institute (PNPI), NRC Kurchatov Institute, Orlova roshcha 1, 188300, Gatchina, Russia.

The small-angle neutron scattering (SANS) on the rat lymphocyte nuclei demonstrates the bifractal nature of the chromatin structural organization. The scattering intensity from rat lymphocyte nuclei is described by power law Q^{-D} with fractal dimension approximately 2.3 on smaller scales and 3 on larger scales.

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A search for long-lived particles (LLPs) produced in decays of standard model (SM) Higgs bosons is presented. The data sample consists of 137  fb^{-1} of proton-proton collisions at sqrt[s]=13  TeV, recorded at the LHC in 2016-2018. A novel technique is employed to reconstruct decays of LLPs in the end cap muon detectors.

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Determination of nuclear moments for many nuclei relies on the computation of hyperfine constants, with theoretical uncertainties directly affecting the resulting uncertainties of the nuclear moments. In this work, we improve the precision of such a method by including for the first time an iterative solution of equations for the core triple cluster amplitudes into the relativistic coupled-cluster method, with large-scale complete basis sets. We carried out calculations of the energies and magnetic dipole and electric quadrupole hyperfine structure constants for the low-lying states of ^{229}Th^{3+} in the framework of such a relativistic coupled-cluster single double triple method.

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The prompt production of the charm baryon Λ_{c}^{+} and the Λ_{c}^{+}/D^{0} production ratios were measured at midrapidity with the ALICE detector in pp and p-Pb collisions at sqrt[s_{NN}]=5.02  TeV. These new measurements show a clear decrease of the Λ_{c}^{+}/D^{0} ratio with increasing transverse momentum (p_{T}) in both collision systems in the range 2 View Article and Find Full Text PDF

The molecular chaperone GroEL is designed to promote protein folding and prevent aggregation. However, the interaction between GroEL and the prion protein, PrP, could lead to pathogenic transformation of the latter to the aggregation-prone PrP form. Here, the molecular basis of the interactions in the GroEL-PrP complex is studied with cryo-EM and molecular dynamics approaches.

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Large Shape Staggering in Neutron-Deficient Bi Isotopes.

Phys Rev Lett

November 2021

Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, 188300 Gatchina, Russia.

The changes in the mean-square charge radius (relative to ^{209}Bi), magnetic dipole, and electric quadrupole moments of ^{187,188,189,191}Bi were measured using the in-source resonance-ionization spectroscopy technique at ISOLDE (CERN). A large staggering in radii was found in ^{187,188,189}Bi^{g}, manifested by a sharp radius increase for the ground state of ^{188}Bi relative to the neighboring ^{187,189}Bi^{g}. A large isomer shift was also observed for ^{188}Bi^{m}.

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