Hengzongshu/ArticleAgent huggingface dataset:
We present a method for and results of determination of the field of integral density in the structure of flow corresponding to the Mach interaction of shock waves at Mach number M = 3. The optical diagnostics of flow was performed using an interference technique based on self-adjusting Zernike filters (SA–AVT method). Numerical simulations were carried out using the CFS3D program package for solving the Euler and Navier–Stokes equations. Quantitative data on the distribution of integral density on the path of probing radiation in one direction of 3D flow transillumination in the region of Mach interaction of shock waves were obtained for the first time.
The self-oscillation of the cavitating vortices is one of the dangerous phenomena of hydraulic turbine operation near full-load conditions. This work is an attempt to generalize data and expand insight on the phenomenon of self-excited oscillations by comparing the experimental results obtained on a simplified turbine and scaled-down pump–turbine models. In both cases, a series of high-speed imaging was carried out, which made it possible to study these phenomena with high temporal resolution. The high-speed imaging data was subjected to additional processing such as binarization, cropping, and scaling. For a simplified turbine model, the volume of the vapor cavity was calculated based on the assumption of the axial symmetry of the cavity, after which fast Fourier transform (FFT) analysis was carried out. A proper orthogonal decomposition (POD) analysis was also performed to examine individual modes in the original digital imaging data. For the pump–turbine, visualization data on the cavitation cavity oscillations were supplemented by pressure measurements in the draft tube cone to determine the frequency characteristics. Based on obtained experimental data, an improved one-dimensional model describing the oscillations of the cavitation cavity arising behind the hydraulic turbine runner is proposed.
On the basis of 2H NMR spin relaxation analysis, the motional mechanism for propene and propane within a ZIF-8 framework is elucidated and microscopic translational diffusion characteristics for these hydrocarbons have been estimated.
Lateral heterojunctions of atomically precise graphene nanoribbons (GNRs) hold promise for applications in nanotechnology, yet their charge transport and most of the spectroscopic properties have not been investigated. Here, we synthesize a monolayer of multiple aligned heterojunctions consisting of quasi-metallic and wide-bandgap GNRs, and report characterization by scanning tunneling microscopy, angle-resolved photoemission, Raman spectroscopy, and charge transport. Comprehensive transport measurements as a function of bias and gate voltages, channel length, and temperature reveal that charge transport is dictated by tunneling through the potential barriers formed by wide-bandgap GNR segments. The current-voltage characteristics are in agreement with calculations of tunneling conductance through asymmetric barriers. We fabricate a GNR heterojunctions based sensor and demonstrate greatly improved sensitivity to adsorbates compared to graphene based sensors. This is achieved via modulation of the GNR heterojunction tunneling barriers by adsorbates.
The three-dimensional organization of the genome is tightly connected to its biological function. The Hi-C approach was recently introduced as a method that can be used to identify higher-order chromatin interactions genome-wide.

The aim of this study was to determine genome-wide chromatin interaction frequencies using the Hi-C approach in mouse sperm cells and embryonic fibroblasts.

The obtained data demonstrate that the three-dimensional genome organizations of sperm and fibroblast cells show a high degree of similarity both with each other and with the previously described mouse embryonic stem cells. Both A- and B-compartments and topologically associated domains are present in spermatozoa and fibroblasts. Nevertheless, sperm cells and fibroblasts exhibit statistically significant differences between each other in the contact probabilities of defined loci. Tight packaging of the sperm genome results in an enrichment of long-range contacts compared with the fibroblasts. However, only 30% of the differences in the number of contacts are based on differences in the densities of their genome packages; the main source of the differences is the gain or loss of contacts that are specific for defined genome regions. We find that the dependence of the contact probability on genomic distance for sperm is close to the dependence predicted for the fractal globular folding of chromatin. Overall, we can conclude that the three-dimensional structure of the genome is passed through generations without being dramatically changed in sperm cells.
coherent population trapping (CPT) resonances

A method of dynamic continuous-wave spectroscopy using phase modulation of the jump type is developed. The time evolution of the spectroscopic signal is investigated. A method for the formation of an error signal for frequency stabilization is proposed.

We show that our approach has a reduced sensitivity to the lineshape asymmetry of the CPT resonance. The experimental results are in good qualitative agreement with theoretical predictions based on a mathematical model of a three-level Λ system in a bichromatic field. This method can be used in atomic frequency standards (including chip-scale atomic clocks).
One of concepts giving opportunities for studying of topological insulators in non-magnetic materials, or creating scattering-immune in optical waveguides is creation of synthetic gauge fields in photonic systems. It was shown that gauge fields shift the band-gaps of optical waves, which can be applied to implement one-way nonreciprocal waveguides, even though both the waveguide core and cladding are in a topologically trivial state [1].

In our work we propose a method to create a gauge field in a synthetic photonic mesh lattice – an optical device proved its high versatility for optical experiments [2].

We demonstrate presence of localized modes due to nontrivial gauge field circulation.
New data on both total and differential cross sections of the production of η mesons in proton–deuteron fusion to He3η in the excess energy region 13.6MeV≤Qη≤80.9MeV are presented.

These data have been obtained with the WASA-at-COSY detector setup located at the Forschungszentrum Jülich, using a proton beam at 15 different beam momenta between pp=1.60GeV/c and pp=1.74GeV/c.

While significant structure of the total cross section is observed in the energy region 20MeV≲Qη≲60MeV, a previously reported sharp variation around Qη≈50MeV cannot be confirmed. Angular distributions show the typical forward-peaking that was noted earlier. For the first time, it is possible to study the development of these angular distributions with rising excess energy over a wide interval.
Kotlin is a statically typed programming language that supports object-oriented and functional programming. It supports JVM, JS and native platforms via LLVM (Kotlin / Native). The first two targets are backed with well-developed virtual machines that can perform advanced program optimizations at runtime. However, for native platforms, all optimizations must be performed at compile time. Currently Kotlin / Native lacks many optimizations, which is why the performance of the generated code is poor in many cases. This paper describes a way to solve this problem by introducing an additional SSA-based intermediate representation and implementing escape analysis using it. Experimental results have shown that this approach can significantly improve performance.
Generation of electromagnetic radiation near the second harmonic of the plasma frequency during the injection of an electron beam into a rippled-density plasma channel is investigated using both analytical theory and particle-in-cell simulations. The generating scheme is based on nonlinear interaction of the most unstable beam-driven potential plasma wave with its satellite arising due to scattering on the longitudinal modulation of plasma density. Resulting superluminal oscillations of electric current in a finite-size plasma channel radiate electromagnetic waves via the same mechanism which has been recently studied for the fundamental harmonic emission and reffered as a beam-driven plasma antenna. It is shown that theoretical predictions for the optimal plasma width and modulation period are confirmed by simulation results and the power conversion efficiency of the second harmonic emission reaches several percent. Such an efficient mechanism opens the path to explanation of laboratory experiments with a thin electron beam at the GOL-3 mirror trap as well as to developing the scheme of terahertz generation at the gigawatt power level.
We comprehensively review the deceptively simple concept of dipole scattering in order to uncover and resolve all ambiguities and controversies existing in the literature. First, we consider a point electric dipole in a non-magnetic environment as a singular point in space whose sole ability is to be polarized due to the external electric field. We show that the postulation of the Green's dyadic of the specific form provides the unified description of the contribution of the dipole into the electromagnetic properties of the whole space. This is the most complete, concise, and unambiguous definition of a point dipole and its polarizability. All optical properties, including the fluctuation–dissipation theorem for a fluctuating dipole, are derived from this definition. Second, we obtain the same results for a small homogeneous sphere by taking a small-size limit of the Lorenz–Mie theory. Third, and most interestingly, we generalize this microscopic description to small particles of arbitrary shape. Both bare (static) and dressed (dynamic) polarizabilities are defined as the double integrals of the corresponding dyadic transition operator over the particle's volume. While many derivations and some results are novel, all of them follow from or are connected with the existing literature, which we review throughout the paper.
Drop impact is important for numerous industrial processes. The recent progress in investigations of drop impact on heated solid surface covers the processes near and above the boiling temperature of the liquid. There is a gap in understanding of drop dynamics for the substrate temperature below the liquid boiling point.

We conduct a detailed study of the interaction of the water drop of 10 μl impacting on a heated sapphire plate with a temperature varied within a range of 23–135°C. Characteristic stages of drop interaction with a substrate at various temperatures are identified, namely impact, spreading, rollback, one liquid column splashing, microdrops detachment, formation, stabilization, breakup, boiling, and evaporation.

We show that the spreading time and maximal spreading diameter of the droplet are dominated by inertia and practically independent of the temperature. The influence of the temperature on viscosity dissipation, which limits the maximum spreading diameter, is not significant. However, the temperature rise leads to a considerable decrease of the liquid column contact diameter and to an increase of the liquid column height at the splashing stage. It is revealed that the contact line velocity at the rollback stage depends on temperature. Microdrop detachment from the liquid column is observed for a substrate temperature of 60–100°C. Beginning from the substrate temperature of 100°C, the liquid column height is decreased again. The most important observation is the drop breakup into several sessile microdrops just after the spreading for 135°C, which prevents the rollback and rebound. We show the possible importance of the Marangoni force for thin liquid film breakup and detect the presence of microbubbles, which is also potentially important for breakup.
The entropy production scenarios due to the electroweak phase transition (EWPT) in the framework of the minimal extension of standard model, namely the two Higgs doublet model (2HDM), are revisited. The possibility of first order phase transition is discussed. Intense parameter scanning was done with the help of BSMPT, a C++ package. We perform numerical calculations in order to calculate the entropy production with numerous benchmark points.
Recently, interest in micro-jet research has increased that is related to the potential use of micro-jets in various applications of aerospace and chemical industries. Non-axisymmetric nozzles, in particular rectangular ones, are often used due to design considerations.

The purpose of this work is numerical and experimental study of the ejection of underexpanded micro jets from a slotted nozzle into still air in wide range of jet pressure ratio, height of the rectangular nozzle, and height-to-width ratio. The jets have sonic velocity at the nozzle exit. The paper presents the results of experiments on visualization of the gas micro-jets outflow using a shadowgraph method, as well as longitudinal and transverse pressure distribution measured by Pitot tubes. Numerical simulation of the ejection of underexpanded microjets from the slotted nozzle into still air has been carried out in 2D statement. Calculations have been performed at the same conditions in the still area as experimental ones. Stationary Reynolds-averaged Navier-Stokes equations have been solved for the turbulent flow regime with the turbulence model k-ω SST.

The measurements and visualization of the flow allowed us to obtain parameters: the length both of a non-dimensional average shock cell and the first one.
The well-known evidence of Sextus Empiricus in Adv. Math. 7.65–87 is one of the two major evidence about Gorgias's treatise “On Not-Being or On Nature” along with “De Melisso Xenophane Gorgia”. The paper offers the analyses of the persuasive structure is this passage and discusses the arguments, which Sextus and, presumably, Gorgias use in this treatise. Also the paper compares formal persuasive structure of Gorgias’ treatise as it presented in Adv. Math., on the one hand, and MXG, on the other.
Among the models that become more and more popular in behavioral neuroscience are biosocial models, which allow studying the consequences of chronic social conflicts and social stress in animals. The sensory contact model appears to represent one of such models.

Repeated experience of aggression or social defeats in daily agonistic interactions in male mice of different strains leads to the formation of opposing kinds of social behavior: one attributable to winners (aggressors) and another attributable to losers (defeated males, victims of aggression). A large variety of behavioral pathologies which develop in male mice in these conditions (anxious depression, catalepsy, social withdrawal, pronounced aggression, anxiety, hyperactivity, cognitive disturbances, anhedonia etc.), which are accompanied by somatic changes (reduced gonad function, psychogenic immune deficiency etc), suggest that this approach could be used for different aims of biomedical studies.

Putative mechanisms of release and maintenance of aggressive and submissive behaviors in male mice under the sensory contact model, criteria of correct application, basic experimental setups and problem of the control, methodical capabilities and potentials of the sensory contact model applications are discussed in this paper.
The study is devoted to improving the efficiency of the method of multichannel analysis of surface waves due to the implementation of a new algorithm for the selection of 1D-models of the shear wave velocity by inverse dispersion curves based on machine learning.

It is proposed to use a multilayer fully-connected artificial neural network (ANN) for the estimate of horizontally layered models composed of interpolated velocity values on a uniform grid with an arbitrary step. Various types of correlation dependence of the parameters of the velocity model on dispersion curves were investigated. The optimal type of the objective function was determined for ANN learning on the basis of these studies.

The advantages of using a trained ANN for the problem of inversion dispersion curves are: the ability to estimate layered models with sufficient accuracy for their use at subsequent stages of seismic data processing, resistance to noise, no significant requirements for computational resources and the absence of the need for additional adjustment of parameters. The tests of the trained ANN, with the architecture proposed in this study, show high accuracy in validation (about 96%), which indicates the success of training and the actually perspective of using neural networks for inversion problems.
In scanning interferometry of longitudinal shift, an uncertainty of required phase shift performance leads to a measurement error. Such uncertainty can be caused by external factors (vibrations, air turbulence in measuring area etc.) as well as inaccuracy of the scanning system.

The method for calculating the phase shift between interferograms, which allows reducing the measurement error, is proposed.

The results of numerical and full scale experiments are presented.
the known logarithmic beam-size effect measured in the experiments on a single bremsstrahlung at Novosibirsk's VEPP-4 and DESY HERA

We derive a physically pronounced equation for the event rate which proves that the linear beam-size effect corresponds to the scattering of one beam of particles on the decay products of the other

the linear beam-size effect corresponds to the scattering of one beam of particles on the decay products of the other
The induced pluripotent stem cell (iPSC) lines ICGi008-A and ICGi008-B were generated from dermal fibroblasts using episomal vectors expressing pluripotency factors. Dermal fibroblasts were obtained from a 55 year old male Сaucasian familial Alzheimer's disease (AD) patient carrying heterozygous V717I mutation in the APP gene. The generated iPSC lines maintained the original APP genotype, expressed pluripotency markers, exhibited a normal karyotype and retained the ability to differentiate into cell types of the three germ layers. The iPSC lines will be useful for the study of the AD molecular and cellular mechanisms and drug screening.
Probing an atomic resonance without disturbing it is an ubiquitous issue in physics. This problem is critical in high-accuracy spectroscopy or for the next generation of atomic optical clocks. Ultra-high resolution frequency metrology requires sophisticated interrogation schemes and robust protocols handling pulse length errors and residual frequency detuning offsets.

This review reports recent progress and perspective in such schemes, using sequences of composite laser-pulses tailored in pulse duration, frequency and phase, inspired by NMR techniques and quantum information processing. After a short presentation of Rabi technique and NMR-like composite pulses allowing efficient compensation of electromagnetic field perturbations to achieve robust population transfers, composite laser-pulses are investigated within Ramsey's method of separated oscillating fields in order to generate non-linear compensation of probe-induced frequency shifts. Laser-pulses protocols such as hyper-Ramsey, modified hyper-Ramsey, generalized hyper-Ramsey and hybrid schemes as auto-balanced Ramsey spectroscopy are reviewed.

These techniques provide excellent protection against both probe induced light-shift perturbations and laser intensity variations. More sophisticated schemes generating synthetic frequency-shifts are presented. They allow to reduce or completely eliminate imperfect correction of probe-induced frequency-shifts even in presence of decoherence due to the laser line-width. Finally, two universal protocols are presented which provide complete elimination of probe-induced frequency shifts in the general case where both decoherence and relaxation dissipation effects are present by using exact analytic expressions for phase-shifts and the clock frequency detuning. These techniques might be applied to atomic, molecular and nuclear frequency metrology, Ramsey-type mass spectrometry as well as precision spectroscopy.
Unlike many other viruses, HIV-1 is highly variable. The structure of the viral envelope changes as the infection progresses and is one of the biggest obstacles in developing an HIV-1 vaccine. HIV-1 infection can cause the production of various natural autoantibodies, including catalytic antibodies hydrolyzing DNA, myelin basic protein, histones, HIV-integrase, HIV-reverse transcriptase, β-casein, serum albumin, and some other natural substrates.

Currently, there are various directions for the development of HIV-1 vaccines: stimulation of the immune response on the mucous membranes; induction of cytotoxic T cells, which lyse infected cells and hold back HIV-infection; immunization with recombinant Env proteins or vectors encoding Env; mRNA-based vaccines and some others. However, despite many attempts to develop an HIV-1 vaccine, none have been successful.

Here we review the entire spectrum of antibodies found in HIV-infected patients, including neutralizing antibodies specific to various viral epitopes, as well as antibodies formed against various autoantigens, catalytic antibodies against autoantigens, and some viral proteins. We consider various promising targets for developing a vaccine that will not produce unwanted antibodies in vaccinated patients. In addition, we review common problems in the development of a vaccine against HIV-1.
For martensitic transformations the macroscopic crystal strain is directly related to the corresponding structural rearrangement at the microscopic level.

In situ optical microscopy observations of the interface migration and the change in crystal shape during a displacive single crystal to single crystal transformation can contribute significantly to understanding the mechanism of the process at the atomic scale.

This is illustrated for the dehydration of samarium oxalate decahydrate in a study combining optical microscopy and single-crystal X-ray diffraction.
CpG dinucleotides are targets for epigenetic methylation, many of them bearing 5‐methylcytosine (mCyt) in the human genome. Guanine in this context can be easily oxidized to 8‐oxoguanine (oxoGua), which is repaired by 8‐oxoguanine‐DNA glycosylase (OGG1).

We have studied how methylation affects the efficiency of oxoGua excision from damaged CpG dinucleotides.

Methylation of the adjacent cytosine moderately decreased the oxoGua excision rate while methylation opposite oxoGua lowered the rate of product release. Cytosine methylation abolished stimulation of OGG1 by repair endonuclease APEX1. The OGG1 S326C polymorphic variant associated with lung cancer showed poorer base excision and lost sensitivity to the opposite‐base methylation. The overall repair in the system reconstituted from purified proteins decreased for CpG with mCyt in the damaged strand.
We report an experimental comparison of three-photon-absorption resonances (N-resonances) for the D1 and D2 optical transitions of thermal (87)Rb vapor. We find that the D2 N-resonance has better contrast, a broader linewidth, and a more symmetric line shape than the D1 N-resonance. Taken together, these factors imply superior performance for frequency standards operating on alkali D2 N-resonances, in contrast with coherent population trapping resonances, for which the D2 transition provides poorer frequency standard performance than the D1 transition.
Effects of light millicharged dark matter particles on primordial nucleosynthesis are considered. It is shown that if the mass of such particles is much smaller than the electron mass, they lead to strong overproduction of Helium-4. An agreement with observations can be achieved by non-vanishing lepton asymmetry. Baryon-to-photon ratio at BBN and neutrino- to-photon ratio both at BBN and at recombination are noticeably different as compared to the standard cosmological model. The latter ratio and possible lepton asymmetry could be checked by Planck. For higher mass of new particles the effect is much less pronounced and may even have opposite sign.