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Impact of Chronic Oral Administration of Silver Nanoparticles on Cognitive Abilities of Mice
No full textTo assess the effect of silver nanoparticles on mice cognitive abilities, daily, up to 4-month period, experimental mice were administrated with silver nanoparticles solution. Accumulation of silver in brain was assessed by neutron activation analysis. Cognitive abilities in mice before and after silver nanoparticles administration were evaluated in the Morris water maze behavioral test. No significant differences in the amounts of silver accumulated in brain were found between capable and incapable animals. Silver accumulation in brain of experimental animals in 4-months experiment was higher than in 2-months experiment for both groups. In the main Morris water maze behavioral test at the control points of 2 and 4 months no statistically significant differences were found in the parameters of treks between experimental and control animals
Development of a Reference Database for Beta-Delayed Neutron Emission
No full textBeta-delayed neutron emission is important for nuclear structure and astrophysics as well as for reactor applications. Significant advances in nuclear experimental techniques in the past two decades have led to a wealth of new measurements that remain to be incorporated in the databases.We report on a coordinated effort to compile and evaluate all the available β -delayed neutron emission data. The different measurement techniques have been assessed and the data have been compared with semi-microscopic and microscopic-macroscopic models. The new microscopic database has been tested against aggregate total delayed neutron yields, time-dependent group parameters in 6-and 8-group re-presentation, and aggregate delayed neutron spectra. New recommendations of macroscopic delayed-neutron data for fissile materials of interest to applications are also presented. The new Reference Database for Beta-Delayed Neutron Emission Data is available online at: http://www-nds.iaea.org/beta-delayed-neutron/database.html
Influence of relativistic rotation on the confinement-deconfinement transition in gluodynamics
No full textIn this paper we consider the influence of relativistic rotation on the confinement-deconfinement transition in gluodynamics within lattice simulation. We perform the simulation in the reference frame which rotates with the system under investigation, where rotation is reduced to external gravitational field. To study the confinement-deconfinement transition, the Polyakov loop and its susceptibility are calculated for various lattice parameters and the values of angular velocities that are characteristic for heavy-ion collision experiments. Different types of boundary conditions (open, periodic, Dirichlet) are imposed in directions, orthogonal, to rotation axis. Our data for the critical temperature are well described by a simple quadratic function Tc(Ω)/Tc(0)=1+C2Ω2 with C2>0 for all boundary conditions and all lattice parameters used in the simulations. From this we conclude that the critical temperature of the confinement-deconfinement transition in gluodynamics increases with increasing angular velocity. This conclusion does not depend on the boundary conditions used in our study and we believe that this is universal property of gluodynamics
Scalar isoscalar mesons and the scalar glueball from radiative decays
No full textA coupled-channel analysis of BESIII data on radiative J/ψ decays into ππ , KK¯ , ηη and ωϕ has been performed. The partial-wave amplitude is constrained by a large number of further data. The analysis finds ten isoscalar scalar mesons. Their masses, widths and decay modes are determined. The scalar mesons are interpreted as mainly SU(3)-singlet and mainly octet states. Octet isoscalar scalar states are observed with significant yields only in the 1500-2100 MeV mass region. Singlet scalar mesons are produced over a wide mass range but their yield peaks in the same mass region. The peak is interpreted as scalar glueball. Its mass and width are determined to M=1865 ±25 −30+10 MeV and Γ=370 ± 50−20+30 MeV, its yield in radiative J/ψ decays to ( 5.8±1.0)10−3
Multinucleon Transmissions in O (35 MeV/Nucleon) + Ta (Be) Reactions
No full textThe velocity, charge, and isotopic distributions of the products of nuclear reactions with 2 ≤ Z ≤ 11 have been studied in combinations of O (35 MeV/nucleon) + Та (Ве) with a different isotope spin. The correlation of the isotope yields for the detected light elements with value Qgg has been established. The cross sections for the formation of neutron-rich nuclei have been measured and their yields in reactions with different neutron skin have been compared. A qualitative interpretation of the phenomenon of a significant increase in the probability of the formation of neutron-rich nuclei of light elements in reaction О (35 MeV/nucleon) + Та in comparison with О (35 MeV/nucleon) + Ве obtained in the reactions with the removal of a proton from the projectile nucleus has also been presented
Beyond Horndeski interactions induced by quantum effects
No full textOpportunity to generate beyond Horndeski interactions is addressed. An amplitude generating a certain beyond Horndeski coupling is explicitly found. The amplitude is free from ultraviolet divergences, so it is protected from ultraviolet contributions and can be considered as a universal prediction of effective field theory
The use of Boosted Decision Trees for Energy Reconstruction in JUNO experiment
No full textThe Jiangmen Underground Neutrino Observatory (JUNO) is a neutrino experiment with a broad physical program. The main goals of JUNO are the determination of the neutrino mass ordering and high precision investigation of neutrino oscillation properties. The precise reconstruction of the event energy is crucial for the success of the experiment. JUNO is equiped with 17612 + 25600 PMT channels of two kind which provide both charge and hit time information. In this work we present a fast Boosted Decision Trees model using small set of aggregated features. The model predicts event energy deposition. We describe the motivation and the details of our feature engineering and feature selection procedures. We demonstrate that the proposed aggregated approach can achieve a reconstruction quality that is competitive with the quality of much more complex models like Convolution Neural Networks (ResNet, VGG and GNN)
ЭКСТРАПОЛЯЦИОННЫЕ ОЦЕНКИ ФИЗИКО-ХИМИЧЕСКИХ ХАРАКТЕРИСТИК НИХОНИЯ, ТЕННЕССИНА И ОГАНЕСОНА
No full textМетод сравнительного расчета, основанный на корреляции одних свойств с другими в группе элементов-аналогов и неоднократно применявшийся для определения свойств астата, можно использовать для оценки некоторых физико-химических свойств теннессина, оганесона и нихония. В группах этих элементов наблюдается прямолинейная зависимость одних их свойств от других свойств
