Hengzongshu/ArticleAgent huggingface dataset:
A novel effect of fast heating and charging a finite-radius plasma is discovered in the context of plasma wakefield acceleration.

As the plasma wave breaks, most of its energy is transferred to plasma electrons. The electrons gain substantial transverse momentum and escape the plasma radially, which gives rise to a strong charge-separation electric field and azimuthal magnetic field around the plasma.

The slowly varying field structure is preserved for hundreds of wakefield periods and contains (together with hot electrons) up to 80% of the initial wakefield energy.
A suspended semiconductor quantum ring interferometer based on a GaAs/AlGaAs heterostructure with a two-dimensional electron gas (2DEG) is created and experimentally studied. The electron interference in suspended 2DEG is observed. The interference manifests itself as the Aharonov-Bohm oscillations of the interferometer magnetoresistance, clearly observed before as well as after suspension. The amplitude of the oscillations remains almost unchanged after suspension.
There are only 10 Euclidean forms, that is flat closed three-dimensional manifolds: six are orientable and four are non-orientable. The aim of this paper is to describe all types of n-fold coverings over orientable Euclidean manifolds G2 and G4, and calculate the numbers of nonequivalent coverings of each type. We classify subgroups in the fundamental groups π1(G2) and π1(G4) up to isomorphism and calculate the numbers of conjugated classes of each type of subgroups for index n. The manifolds G2 and G4 are uniquely determined among the others orientable forms by their homology groups H1(G2)=Z2×Z2×Z and H1(G4)=Z2×Z.
Dans la littérature consacrée aux associations évoquées par les mots le substantif ami occupe une place de choix. En effet on l’a souvent utilisé dans une optique comparatiste dans le but de montrer les différences et similitudes entre l’image mentale véhiculée dans les différentes langues.

Dans cette étude nous allons analyser comment cette image a évolué en français durant les quinze dernières années. Pour cela nous allons utiliser les données des différents dictionnaires d’associations évoquées par les mots disponibles pour le français, créés à partir de questionnaires depuis 2007. Nous utiliserons tant les données issues des dictionnaires directs que celles des dictionnaires inverses, pour la France, la Belgique, la Suisse et le Canada sur une période allant de 2007 à 2020.
In the South Urals, we have identified and investigated two platinum-bearing formations – ophiolite chromitebearing complexes, and the Khudolaz differentiated mafic-ultramafic complex with sulfide Cu-Ni mineralization. The ophiolite chromite-bearing complexes include fragments of the upper mantle and lower crust of the Paleouralian Ocean, which were induced by collision onto the edge of the East European platform. The origin of the Khudolaz complex is related a mantle plume activity. Here, we review and compare the main features of platinum-metal mineralization (PMM) in these two formations. The article presents the results of mineralogical and geochemical studies of PMM associated with chromite and sulfide Cu-Ni ores. In association with chromitites, two types of PMM are distinguished: (1) predominating refractory platinoids in chromitites of the mantle unit of the section, and (2) predominating platinum and palladium in chromitites of the transitional wehrlite-clinopyroxenite complex. Compositions of platinum group minerals (PGM) and relations between their elements and host minerals suggest that the minerals of the ophiolite chromite-bearing complexes are of a restite origin, while the Khudolaz complex results from a combination of magmatic processes and solid-phase redistribution of material. Palladium (michenerite, froodite, merenskyite, borovskite, sudburyite) and platinum (sperrylite, moncheite) minerals are found in magmatic sulfide ores of the Khudolaz complex, which were subjected to hydrothermal metasomatization. Texture observations using electron microscope and optical (reflected light) images, as well as LA ICP MS analyses of sulfides suggest late- and post-magmatic crystallization of PMM in three phases: (1) immiscible metalloid or highly fractionated residual sulfide melts trapped in sulfides; (2) segregation of isomorphic impurities of platinum group elements (PGE) and chalcogenide elements from sulfide solid solutions; and (3) interaction of hydrothermal fluids with soluble sulfides. Prospective for PMM are extended bodies of disseminated chromitites in marginal dunites of the Kraka and Nurali massifs, and wehrlite-clinopyroxenite complexes of the same massifs containing PGE (above 500 ppb). In the Khudolaz complex, promising PMM bodies are low-metasomatized parts of sulfide ore bodies (1 ppm of ΣPGE and above) located in the largest massifs, Severny Buskun and Zapadny Karasaz. Exocontact zones of these intrusions are also promising for PMM.
A test facility for experimental simulation of transient heat load expected for ELMs type I events in ITER is developed at BINP SB RAS. Dynamics of tungsten particles in the ablation plume is investigated by small-angle light scattering technique and using fast CCD and ICCD cameras. The threshold of intense particle generation, sizes and velocities of particles ejected from the surface are estimated.
The article is dedicated to the twentieth anniversary of two Internet physics olympiads organized by the Physics Department of Novosibirsk State University, in which senior pupils from Russia and the USA participated. For the time when before the advent of popular social networks there were a few more years when the currently popular messengers were not yet widespread, the organization of such competitions was technically and organizationally far from a trivial task. It was also necessary to overcome the problem of different programs and different levels of school physics teaching in Russia and the USA, as well as the problem of the language barrier.

All these tasks were successfully solved by the joint efforts of the Russian and American organizing committees, and in 1999 the competitions Novosibirsk – San Diego and in 2000 Novosibirsk – St. Petersburg – San Diego – Seattle were held. A successful invention that allowed equalizing the chances of teams and replacing interethnic rivalry with cooperation was the idea to hold competitions between international teams, consisting of an equal number of Russian and American schoolchildren communicating with each other via direct video communication. Sets of tasks were prepared for the olympiads, both ordinary, written, and video clips with tasks-demonstrations. The latter have been particularly successful in resolving the problem of the language barrier. The great help in conducting these two Olympiads was the many years of experience gained by NSU during the All-Siberian Olympiads and the idea of the demonstration tasks used in entrance examinations at the Physics Department of NSU.

We present in this article both the content of the tasks of the Olympiads and the responses of the domestic and American press to the events described.
There exists a great deal of concrete evidence in favor of the exotic four-quark nature of light scalars. At the same time, the further expansion of the area of the $q^2\bar q^2$ model validity for light scalars on ever new processes seems extremely interesting and important.

We analyze the BESIII data on the decay $J/\psi\to \gamma\pi^0\pi^0$ and show that the results of this high-statistics experiment can be interpreted

in favor of the four-quark nature of light scalar mesons $f_0(980)$ and $f_0(500)$.
We report on the observation of cyclotron resonance induced photocurrents, excited by continuous wave terahertz radiation, in a 3D topological insulator (TI) based on an 80 nm strained HgTe film. The analysis of the photocurrent formation is supported by complimentary measurements of magneto-transport and radiation transmission.

Studying the resonance response in a gated sample we examined the behavior of the photocurrent, which enables us to extract the mobility and the cyclotron mass as a function of the Fermi energy. For high gate voltages we also detected cyclotron resonance (CR) of bulk carriers, with a mass about two times larger than that obtained for the surface states.

We demonstrate that the photocurrent is generated in the topologically protected surface states. The origin of the CR assisted photocurrent is discussed in terms of asymmetric scattering of TI surface carriers in the momentum space. Furthermore, we show that studying the photocurrent in gated samples provides a sensitive method to probe the effective masses and the mobility of 2D Dirac surface states, when the Fermi level lies in the bulk energy gap or even in the conduction band.
Background/Aim: We compared the therapeutic efficacy of two recently developed experimental anticancer technologies: 1) in situ vaccination based on local immunotherapy with CpG oligonucleotides and anti-OX40 antibodies to activate antitumor immune response and 2) "Karanahan" technology [from the Sanskrit kāraṇa ('source') + han ('to kill')] based on the combined injection of cyclophosphamide and double-stranded DNA to eradicate cancer stem cells.

Materials and Methods: The anticancer approaches were compared on three types of mouse malignant tumors with different grades of immunogenicity: weakly immunogenic carcinoma Krebs-2, moderately immunogenic Lewis carcinoma, and highly immunogenic A20 В-cellular lymphoma.

Results: Our results indicated that in situ vaccination was the most effective against the highly immunogenic tumor А20. In addition, "Karanahan" demonstrated high efficiency in all types of tumors, regardless of their immunogenicity or size. Conclusion: "Karanahan" therapy showed higher efficacy relative to in situ vaccination with CpG oligonucleotides and anti-OX40 antibodies.
Molybdenum octahedral clusters, when incorporated into an appropriate polymer matrix, are considered as promising agents for a range of biological applications. This work describes the one-pot synthesis, morphology and cellular toxicity of nano-sized polystyrene beads doped with luminescent cluster complexes [{Mo6X8}(NO3)6]2− (X = Cl, Br or I). Specifically, the particles were obtained by free radical dispersion copolymerisation of styrene and methacrylic acid or 4-vinylpyridine in the presence of the cluster complexes. The effects of the cluster loading in the reaction mixture on both the content of the final material and number-average molar mass of the copolymers were evaluated. © 2017 Society of Chemical Industry
The crisis in a FC-72 liquid film moving under the action of a gas flow through a smooth and micro-grooved heater was experimentally investigated. It is shown that the use of micro-grooves leads to an increase of the critical heat flux.
The subject of this paper is molecular stochastic modeling the transport processes in liquids. The proposed method and the corresponding algorithm are an alternative to the molecular dynamics method.

However, unlike the latter the system of Newtonian equations is not solved for modeling the phase trajectories of the system studied. The phase trajectories of the molecular system are simulated stochastically. For this purpose, the database of the intermolecular forces acting on each molecule of the system during the considered time interval has been created. The distribution function of these forces has been built. It was shown that this distribution function can be approximated by certain analytic function. The dependency of the parameters of this function on the liquid temperature and parameters of the intermolecular interaction potential (the Lennard-Jones interaction potential is used) is determined. Using this distribution function the force acting on each molecule at given time is determined. After that the coordinates and velocity of all molecules of the system are calculated.

As a result, the full information about the phase variables of the molecular system is obtained. All macroscopic characteristics of the system (temperature, pressure, transport coefficients etc.) are calculated by means of the methods of nonequilibrium statistical mechanics. The transport coefficients are calculated using fluctuation-dissipation theorems that relate transport coefficients to the evolution of the corresponding correlation functions. The algorithm was tested on the calculation of the viscosity of several simple liquids.
The first iodide cluster of molybdenum with the metal cage in the form of a tetragonal pyramid (Bu 4 N)[Mo 5 OI 13 ]·THF ( I ) and cocrystallizate (Bu 4 N){[Mo 5 OI 13 ] 0.9 [Mo 6 I 14 ]·THF ( II ) are synthesized for the first time by heating a LiI–I 2 –Mo mixture in a temperature range of 300–400°С followed by the extraction of the product. Complexes I and II are studied by X-ray diffraction analysis (CIF files CCDC nos. 2063029 ( I ) and 2063030 ( II )). The molybdenum atoms in [Mo 5 OI 13 ] – form a square pyramid with Mo–Mo distances of 2.67 Å between the basal molybdenum atoms and the Mo–Mo distances equal to 2.72 Å between the apical and basal molybdenum atoms. The oxygen atom is coordinated to the pyramid base (Mo–μ 4 -O 2.10 Å). The cluster anion [Mo 5 OI 13 ] – can be presented as the octahedral cluster anion [Mo 6 I 14 ] 2– in which the position of the {MoI} – fragment ( d 0 , 6e) is occupied by the isoelectronic oxygen atom ( s 2 p 4 , 6e). In the structure of compound II , the [Mo 5 OI 13 ] – and [Mo 6 I 14 ] 2– cluster anions occupy close atomic positions.
[VNb12O40]15− polytopic ligand can coordinate to up to five {(C6H6)Ru}2+ groups. Combined analytical separation tools together with 1H DOSY NMR were firstly applied to the solution studies of polyoxoniobate based complexes.
Activation-induced deaminase (AID) is the master regulator of class switch recombination (CSR) and somatic hypermutation (SHM), but the mechanisms regulating AID function are obscure.

The differential pattern of switch plasmid activity in three IgM(+)/AID(+) and two IgG(+)/AID(+) B cell lines prompted an analysis of global gene expression to discover the origin of these cells. Gene profiling suggested that the IgG(+)/AID(+) B cell lines derived from germinal center B cells. Analysis of SHM potential demonstrates that the IgVkappa domains are inducibly diversified at high rate during in vitro culture. The mutation spectra focused to A:T base pairs, revealing a component of the hypermutation program that occurs preferentially during phase 2 of SHM. The A:T error spectra were analyzed and were not characteristic of polymerase eta activity. A differential pattern of three consensus motifs used for A:T base substitutions was observed in WT and Poleta-, Msh2- and Msh6-deficient B cells.

Strikingly, mutations in our B cell lines recapitulated the mutable motif profile for Poleta and Msh2 deficiency, respectively, and suggest that an additional pathway for the generation of A:T mutations in SHM is conserved in mouse and human.
A collection of known sites we designated as PDBSite was set up by automated processing of the PDB database using the data on site localization in the SITE field. Additionally, protein-protein interaction sites were generated by analysis of atom coordinates in heterocomplexes. The total number of collected sites was more than 8100; they were assigned to more than 80 functional groups.

PDBSiteScan is a web-accessible program designed for searching three-dimensional (3D) protein fragments similar in structure to known active, binding and posttranslational modification sites. PDBSiteScan provides automated search of the 3D protein fragments whose maximum distance mismatch (MDM) between N, Calpha and C atoms in a fragment and a functional site is not larger than the MDM threshold defined by the user. PDBSiteScan requires perfect matching of amino acids.

PDBSiteScan enables recognition of functional sites in tertiary structures of proteins and allows proteins with functional information to be annotated.
At the VEPP-4M collider the record accuracy of 10−6 of an absolute beam energy calibration was achieved with the resonant depolarization technique in the energy range including the J/ψ, ψ(2S), ψ(3770) resonances as well as the τ - lepton production threshold.

This report discusses the methods, equipment

and the results.
An important problem of oil well diagnostics is to quickly determine changes in the amount of liquid entering the well (flow rate), and the ratio of the amount of water to the amount of liquid (water cut). To calculate these parameters, thermodynamic measurements (temperature, pressure) can be used at the wellhead and downhole of the well, as well as garlands at the wellhead of sensors 10-20 meters long, with a frequency of 1 meter, for more information. The article presents a comparative analysis of algorithms for determining these parameters based on the solution of the inverse problem. The results of numerical calculations are presented.
The effect of sonication time during the synthesis of multiwalled carbon nanotubes -polymethylmethacrylate (MWCNT/PMMA) composites by coagulation technique on the MWCNT distribution in the bulk of the composites close to the percolation threshold was systematically studied by SEM and by measurements on specific resistivity in a wide range of voltages and external pressure.

It was found that the resistivity of composites is irreversibly reduced up to 10 5 times during the first 1-3 measurements, while further measurements are characterized by high repeatability. Change of the composite resistivity during the measurements is discussed assuming that several types of contacts between the nanotubes changing during the measurement are present.

It was found that an increase of the sonication time changed the ratio between ohmic and non-ohmic contacts. It affected the type of changes in the sample resistivity during the voltage variation in the range of 0-10 3 V/mm and resulted in a nonuniform dependence of the composite specific resistivity on the sonication time. An increase of the composite volume during the resistivity measurements was observed at the current densities above 4•10 -8 A/cm 2 . New ohmic contacts were found to form when external pressure was applied due to squeezing of the polymer matrix from the space between adjacent nanotubes.
The time dynamics of nonequilibrium charge carrier relaxation processes in SI GaAs:EL2 (semi-insulating gallium arsenide compensated with EL2 centers) and HR GaAs:Cr (high-resistive gallium arsenide compensated with chromium) were studied by the optical pump–terahertz probe technique. Charge carrier lifetimes and contributions from various recombination mechanisms were determined at different injection levels using the model, which takes into account the influence of surface and volume Shockley–Read–Hall (SRH) recombination, interband radiative transitions and interband and trap-assisted Auger recombination. It was found that, in most cases for HR GaAs:Cr and SI GaAs:EL2, Auger recombination mechanisms make the largest contribution to the recombination rate of nonequilibrium charge carriers at injection levels above ~(0.5–3)·1018 cm−3, typical of pump–probe experiments. At a lower photogenerated charge carrier concentration, the SRH recombination prevails. The derived charge carrier lifetimes, due to the SRH recombination, are approximately 1.5 and 25 ns in HR GaAs:Cr and SI GaAs:EL2, respectively. These values are closer to but still lower than the values determined by photoluminescence decay or charge collection efficiency measurements at low injection levels. The obtained results indicate the importance of a proper experimental data analysis when applying terahertz time-resolved spectroscopy to the determination of charge carrier lifetimes in semiconductor crystals intended for the fabrication of devices working at lower injection levels than those at measurements by the optical pump–terahertz probe technique. It was found that the charge carrier lifetime in HR GaAs:Cr is lower than that in SI GaAs:EL2 at injection levels > 1016 cm−3.
We study the processes γγ→K+K−η and γγ→K+K−π0 using a data sample of 519 fb−1 recorded with the BABAR detector operating at the SLAC PEP-II asymmetric-energy e+e− collider at center-of-mass energies at and near the Υ(nS) (n=2,3,4) resonances.

We observe ηc→K+K−π0 and ηc→K+K−η decays, measure their relative branching fraction, and perform a Dalitz plot analysis for each decay.

We observe the K∗0(1430)→Kη decay and measure its branching fraction relative to the Kπ decay mode to be R(K∗0(1430))=B(K∗0(1430)→Kη)B(K∗0(1430)→Kπ)=0.092±0.025+0.010−0.025. The ηc→K+K−η and K∗0(1430)→Kη results correspond to the first observations of these channels. The data also show evidence for ηc(2S)→K+K−π0 and first evidence for ηc(2S)→K+K−η.
Superconducting technology makes it possible to build a high energy $e^+e^-$ linear collider with energy recovery (ERLC) and reusable beams. To avoid parasitic collisions inside the linacs, a twin (dual) LC is proposed.

In this article, I consider the principle scheme of the collider and estimate the achievable luminosity, which is limited by collision effects and available power. Such a collider can operate in a duty cycle (DC) and in a continuous (CW) modes, if sufficient power. With current SC Nb technology ($T=1.8$ K, $f_{\rm RF}=1.3$ GHz, used for ILC) and with power $P= 100$ MW, a luminosity $L \sim 0.33 \times10^{36}\,\rm cm^{-2}s^{-1}$ is possible at the Higgs factory with $2E_0=250$ GeV. Using superconductors operating at 4.5 K with high $Q_0$ values, such as Nb$_3$Sn, and $f_{\rm RF}=0.65$ GHz, the luminosity can reach $L \sim 1.4 \times10^{36} \,\rm cm^{-2}s^{-1}$ at $2E_0=250$ GeV (with P=100 MW) and $L \sim 0.8 \times 10^{36}\,\rm cm^{-2}s^{-1}$ at $2E_0=500$ GeV (with P=150 MW), which is almost two orders of magnitude greater than at the ILC, where the beams are used only once.

This technology requires additional efforts to obtain the required parameters and reliably operation. Such a collider would be the best machine for precision Higgs studies, including the measurement of Higgs self-coupling.
We describe the genetic diversity of 1327 Brucella strains from human patients in Kazakhstan using multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA). All strains were assigned to the B. melitensis East Mediterranean group and clustered into 16 MLVA11 genotypes, nine of which are reported for the first time. MLVA11 genotype 116 predominates (86.8%) and is present all over Kazakhstan indicating existence and temporary preservation of a "founder effect" among B. melitensis strains circulating in Central Eurasia. The diversity pattern observed in humans is highly similar to the pattern previously reported in animals. The diversity observed by MLVA suggested that the epidemiological status of brucellosis in Kazakhstan is the result of the introduction of a few lineages, which have subsequently diversified at the most unstable tandem repeat loci. This investigation will allow to select the most relevant strains for testing these hypotheses via whole genome sequencing and to subsequently adjust the genotyping scheme to the Kazakhstan epidemiological situation.
The physical mechanisms of the deformation-induced structural transformations in molecular crystals, including morphological changes, amorphization and molecular polymorphous conversions in nano-dispersed bioinorganic compounds are discussed in this work.Integrated study using direct structural and structure-sensitive spectroscopic methods allowed obtaining the data on polymorphous transformations, taking place during mechanical activation in calcium gluconate monohydrate (CG).One of the possible reasons for lattice polymorphous transformations and amorphization, observed in the course of mechanical activation of low-symmetry molecular crystals, might be the spatial molecular isomerization.In this case, the disappearance of the translational invariance of the lattice is conditioned by the simultaneous coexistence of the reactants and reaction products, which have dierent stereoorganization of the molecular structure.