bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement of the all-weather profiler
Authors: Zhukov V Y , Rostokin I N , Shchukin G G
Published: December 2021

The article considers the issues of improving the quality of vertical wind profile measurements. In order to make these measurements under any meteorological conditions, data from profilometers operating in different wave ranges, from optical to centimetre, are combined. At the same time, the resolving power of the latter is considerably inferior to that of the former. We propose a way to improve the quality of measurements in the radio band by applying a new method of information processing, using estimates of the width of the spectrum and the peculiarities of their spatial distribution.
Numerical modeling of anisotropic properties of a solid by particle dynamics method
Authors: Sukhanov D Ya , Kuzovova A E
Published: December 2021

A method is proposed for the numerical simulation of acoustic processes in solids based on the particle dynamics approach for describing the anisotropic properties of a solid. It is proposed to consider a solid body in the form of an array of particles located in a cubic body-centered crystal lattice. To set the anisotropic properties of a solid, it is proposed to use its own proportionality force to shift coefficient for each direction. Based on the results of numerical simulation, the dependence of the longitudinal wave velocity on the direction is shown.
Spatiotemporal structure of the electromagnetic field in a forest environment at nanosecond location
Authors: Dorzhiev B Ch , Ochirov O N
Published: December 2021

The results of measurements of the spatio-temporal distribution of direct and reflected signal levels inside a pine forest are presented. Circular diagrams are built on the basis of which it is possible to assess the levels of direct and reflected signals at a bistatic nanosecond location. The obtained diagrams a give spatial picture of the total energy of the electromagnetic field in the forest environment.
Galvanic pH sensor for continuous monitoring of soil parameters in agriculture
Authors: Yuzhakov M S , Filchenko D I , Badin A V , Berzin A K
Published: December 2021

The article discusses trends in agriculture development in digitalization direction, substantiates need for monitoring pH level throughout year. The main solutions existing on market at moment are given, as well as need to develop a pH sensor for USKD-Agro hardware and software complex. The article discusses in detail the ongoing physical and chemical processes, on them basis pH level is determined, circuitry solutions used, as well as pH sensor implementation. The article describes the sensor calibration process, methodology and test results.
Refraction of electromagnetic waves in pseudo-passive media
Authors: Fisanov V V
Published: December 2021

The problem of reflection and refraction of a plane monochromatic wave is considered in the most general formulation for a flat interface of two isotropic pseudo-passive media using the vector covariant approach of F.I. Fedorov. The generalized Fresnel coefficients for the perpendicular and parallel polarizations turn out to be complex values, except for cases when the phase difference of the permeabilities of the two media is zero or 180 degrees. The critical Brewster angles also turn out to be complex quantities. The phenomenon of total reflection, in contrast to passive transparent media, is not realized in pseudo-passive media. The energy coefficients of reflection and transmission are calculated and analyzed. Restrictions imposed on the values of the material parameters of the problem are indicated, which should be taken into account when studying refractive wave phenomena involving pseudo-passive metamaterials.
Investigation of the parameters of the reflected wave near the Brewster angle
Authors: Krylov V P
Published: December 2021

In free space, the relative permittivity is determined by the Brewster formula without taking into account dielectric and magnetic losses. In experimental studies, discrepancies in the angular position of the minimum of the reflected wave from dielectric materials are observed in comparison with calculations, which are known as deviations from Fresnel’s laws. By solving the task of inclined falling wave on an plate made of a dielectric material with complex of the dielectric and magnetic permittivity, the parameters of the reflected wave were calculated, according to which the angles corresponding to the minimum reflection were determined, depending on the dielectric losses of the material. From the condition that the reflected wave is equal to zero, a formula for determining the Brewster angle for a material with dielectric and magnetic losses was analytically obtained, the results of calculations for which coincided with the calculations for the reflected wave in the context of geometric optics. It is determined that in the general case, the conditions for determining the position of the minimum of the complex amplitude and the phase jump by 180° of electromagnetic waves do not coincide and can be found only when solving the task an falling wave on a plate with complex electrodynamic parameters of the material in the context of geometric optics.
Radio imaging using Doppler sensors
Authors: Satarov R N , Yu Kyzmenko I , Shipilov S E
Published: December 2021

The article shows the multi-angle single-frequency probing of the object with the tactical antenna array, which we install and moves on a two-coordinate scanner. For testing the possibility of using this approach, we made statistical studies. Presented radio images show that using the scanner makes possible to detect metal and dielectric objects. Achieved resolution sufficient to identify forbidden items
Questions of application of fiber-optic sensors for monitoring crack growth during rock deformations
Authors: Yugay V V , Sh Madi P , Ozhigina S B , Gorokhov D A , Alkina A D
Published: December 2021

The paper considers ways to solve the problem of developing a system for monitoring displacement in quarries, which are the main main cause of the collapse of boards and berms in quarries. To ensure safety and constant monitoring during work at the quarry, there are chiseled fiber-optic sensors. The fiber-optic sensor is made on the basis of a single-mode optical fiber, which makes it possible to measure the displacements of the mountain range at distances of about 30 km with high accuracy. Laboratory sample a fiber-optic sensor in its work uses a method for monitoring additional losses that occur during mechanical action on an optical fiber. The fiber-optic sensor was made to show a fairly high linearity and accuracy during measurements and can be used to control the deformation of the array after appropriate refinement of its design. This article is aimed at creating means of controlling the process of deformation and displacement of a mountain massif. Ultimately, the results of the study will help prevent accidents associated with the collapse of the sides. Since the growth of cracks in the rocks of the bort mountain massif leads to its sudden collapse and creates a significant danger for personnel, it also causes the failure of mining equipment.
Influence of durative drainage melioration on the soil macrofauna (The Leningrad region)
Authors: Aparin B , Pyatina E , Kasatkina G
Published: December 2021

The soil-zoological research took place in 2018 on the territory of the soil-hydromeliorative station “Malinovsky” of Lisinsky educational-experimental forest farm (Tosnensky district, Leningrad region, Russia) which was drained in 1973-1974. The purpose of this research is a comparative evaluation of the density of the population and taxonometric variety of eco-functional groups of macrofauna on the Gleysols Histic Drainic after 45 year draining period and the similar biotop without drainage. The constitution of group and species and the trophic structure of soil macrofauna have been researched. 118 individuals of geobionts out of 3 types and 6 classes have been collected. It’s been stated that zoophages are the trophic dominating group. After 45 year draining period a poor groups and species constitution, a low number of large soil invertebrates and a small share of saprophages have survived which corresponds to the fauna of the soil in oligotrophic bogs.
Effects of wildfire on the water chemistry of the northeastern part of the Great Vasyugan Mire (Western Siberia)
Authors: Kharanzhevskaya Yu A , Sinyutkina A A
Published: December 2021

In this study, we determined the effect of wildfire in 2016 on the water chemistry of the northeastern drained part of the Great Vasyugan Mire. The influence of the pyrogenic factor on the water chemistry of the Great Vasyugan Mire was marked by an increase in concentrations of Na+, K+, Ca2+, Mg2+, Fetotal, SO4
2–, HCO3
–, NO–
3, Zn, Cu, Pb, and Cd. The maximum concentrations were observed in the spring (April) during the snow melting period, as well as during the rewetting period after the summer drought. In 2018–2019, there was a decrease in the concentration of the components in the waters after the fire in 2016 (SO4
2–, HCO3
–, NO–
3, Pb, Cd, Zn). An increase in the content of Na+, K+, Ca2+, Mg2+, NH+
4, and Cu was noted, which is associated with the intensification of the processes of mineralisation of plant residues in the upper burnt peat layers.
Geotechnical properties of yellow silty sand soil modified by bio-stimulation with presence of NiCl2
Authors: Qu Jili , Cheng Jinrui , Wang Junfeng
Published: December 2021

Microbiologically induced calcite precipitation (MICP) is now widely tried to improve the quality of mostly sandy soil due to its application prospect to sustainability, environment-friendly and cost-efficiency. The present study is aiming to evaluate the feasibility of bio-stimulation, one of MICP techniques, for strengthening the engineering quality of Shanghai silty sand soil, a special type of soil located in low hillside of west Shanghai, as well as the influence of two factors: CaCl2 as a cementing material and NiCl2 as a co-factor, which was rarely researched before and can be viewed as the influence of urease activity on bio-stimulation result. The direct shear test, unconfined compressive test, supersonic wave test and calcite mass test have been carried out to evaluate engineering performance of yellow silty sand soil enhanced by bio-stimulation method as well as their relationship with concentration of CaCl2 and NiCl2 solutions. The result shows that bio-stimulation method can significantly promote the characteristics of Shanghai yellow silty sand soil and there seems to be extreme point for concentration of CaCl2 and NiCl2 solution in improving the quality of Shanghai yellow silty sand. Microstructure and composition of treated soil by bio-stimulation method have also been analyzed by Scanning Electron Microscope (SEM) and Energy dispersive Spectrometer (EDS), with giving the corresponding micro-mechanism of bio-cementation among soil particles.
Investigation of dielectric heating method of zinc-containing materials for chlorides removal
Authors: Ryazanov A G , Mikhailov G G , Khmeleva O V , Savina Y D , Galimov D M , Senin A V
Published: December 2021

The technological development of the world community makes it necessary to resolve the issues of the produced industrial residues utilization. Worn-out galvanized metal cars, ceilings and other metal structures require orderly utilization. Utilization of galvanized scrap may be carried out in Electric Arc Furnaces (EAF) to obtain intermediate steel and EAF dust. Electric Arc Furnaces dus contains zinc, so it is used as a secondary raw material for the production of metallic zinc. Waelz oxides are formed in Waelz kilns, after the primary processing of EAF dust. Waelz oxide contains halides that must be removed first. Halides may be removed by heating to temperatures of about 1000°C. Dielectric (microwave) heating is a promising and environmentally friendly method for material processing. Microwave heating is carried out without burning natural gas, which leads to decrease of waste gases volume. The work experimentally confirmed the possibility of zinc-containing materials heating at electromagnetic emission exposure. The duration of products heating up to the temperature of 1000°C was 128 - 188 s. The residual content of chloride ions in the calcined products is less than 0.05 wt%.
Feed additive for quails based on fermented brewer’s spent grain
Authors: Yurina N.A. , Labutina N.D. , Danilova A.A. , Vlasov A.B. , Khorin B.V. , Yurin D.A.
Published: December 2021

The paper discusses the effect of a newly developed complex feed additive Grainbiosorb used in complete feed on livability, age of first egg laying, egg productivity, and feed consumption for the production of 1 dozen eggs of laying quails of the Texas white broiler breed. The scientific experiment was carried out in the experimental vivarium of Krasnodar Research Centre for Animal Husbandry and Veterinary Medicine according to the standard technique recommended by the Federal Scientific Center “All-Russian Research and Technological Institute of Poultry” of Russian Academy of Sciences, (Sergiev Posad, 2013). The developed complex feed additive Grainbiosorb consists of fermented brewer’s spent grain, a mineral sorbing complex and probiotic microorganisms. Brewer’s spent grain is pre-fermented with probiotic bacterial concentrate, consisting of lactic acid, and propionic acid microorganisms. The use of fermented brewer’s spent grain in combination with a mineral complex can solve the problems of metabolism, digestion, exposure to heavy metals and thereby increase productivity and contribute to obtaining safe poultry products. The livability of the quail population in experimental and control groups was the same and amounted to 90.0%. The quails of the first group laid the first egg at the age of 44 days, while the quails of the second group at the age of 42 days. Gross egg production for the period of the experiment per the initial laying quail and the egg production for the average laying quail increased in the experimental group relative to the control by 3.8%. The intensity of egg production in the experimental group increased by 2.3 abs. % relative to that in the control group. Feed consumption for the production of 1 dozen quail eggs decreased by 5.5% in the experimental group, relative to the control.
Comparative analysis of methods for determining the flammability of municipal solid waste as railway transport cargo
Authors: Koroleva L A , Khaidarov A G , Ivakhnuk G K , Antoshina T N , Boyakhchyan A A
Published: December 2021

A statistical analysis of information about fires that occurred on the railroads shows that it is necessary to enhance the fire protection measures while transporting the fire-hazardous materials (FHM). A comparative analysis of the use of the exergetic index and the flammability potential for forecasting the fire risks connected to the railroad FHM transportation has been performed. The studies considered municipal solid waste (MSW) as promising railway cargo. The values of the MSW chemical exergy and the heat of combustion have been calculated. The conditions and behavior of their variations have been investigated. A system of the substances and materials classification that is based on the exergetic coefficient was introduced. The proposed approach allows us to resolve methodological problems caused by the requirement to account for the technical, economical criteria, and the fire risk indexes into a unified classification system. The conception of the exergetic index improves the objectivity of the procedure for the estimation of the MSW flammability properties.
Engineering-geological and geoecological aspects of formation of dry dumps on hydrodumps
Authors: Kutepov Yu I , Kutepova N A , Kutepov Yu Yi , Vasileva A D , Mukhina A S , Smirnov R D
Published: December 2021

The paper discusses the issues of increasing the dumping capacity of hydrodumps and their reclamation by filling them with dump embankments from relatively strong overburden. Without the implementation of this measure, the alluvial massifs are inaccessible for a long time for various mining and transport equipment due to the low bearing capacity of the rocks. The specifics of the formation of the composition, state and properties of rocks of alluvial massifs due to the development of fractionation and filtration consolidation processes are noted. The technology of dumping the surface of hydrodump by controlled deformation of the slopes of the first dump layer has been substantiated. A method has been developed for predicting the parameters of intrusion-replacement of alluvial rocks by bulk ones using numerical modeling of the FEM in the Euler formulation. The obtained mechanical properties and regularities of the deformation behavior of technogenic rocks were used to perform geomechanical calculations when justifying the stable parameters of the slopes of the formed natural-technical systems (NTS) “hydrodump+dump” and compaction of embankments to justify the mining-technical stage of reclamation. A geoecological assessment of the impact of the dump NTS on the natural environment has been carried out, which is expressed in the acquisition of land from circulation and the disruption of the natural landscape. The conditions for the formation of technogenic eluvium on the surface of the dump suitable for biological reclamation are considered.
Geoecological and economic assessment of the municipal solid waste management system in the Kaluga region
Authors: Lykov I N , Obolenskaya E V
Published: December 2021

The removal of solid household waste to landfills is the most commonly used method of solid waste disposal and an important source of environmental pollution. Physical, chemical and biochemical processes occur in the body of a solid waste dump, which overlap each other and form an artificial aquifer and biogas. This article provides a brief overview of the environmental problems associated with the practice of garbage disposal and the negative impact of the landfill on the environment. The data on the features of the functioning of the solid waste landfill in Kaluga, on the dynamics of waste generation and changes in their morphological composition are presented. The issues related to the economic problems of waste disposal are considered.
Method for milk whey microfiltration with filtrate pulsed backpressure and installation for its implementation
Authors: Korysheva N N , Titov S A , Shakhov S V , Tikhonov G S , Glotova I A , Galochkina N A
Published: December 2021

During deep processing of whey using microfiltration, the loss of membrane efficiency can take place. In this work, an installation for microfiltration of milk whey has been developed. It includes pumps, containers with liquids, throttling valves, a pressure gauge, and a microfiltration cell with a tubular ceramic membrane. A thin titanium oxide layer was deposited on the inner surface of the porous alumina tube. The outer diameter of the tubes is 10 mm, the wall thickness is 2 mm, the length of the tubes is 45 cm. A homogenized aqueous dispersion of sugar beet fiber was used as an agent that improves the performance of the installation by creating a pulsed backpressure of the filtrate. It is shown that the use of a finely ground suspension of dietary fiber during microfiltration of milk whey through a tubular ceramic membrane prevents the formation of protein deposits on the membrane and in its pores. The installation allows obtaining a suspension of dietary fiber, enriched with milk protein, as an additional product. The protein-enriched fiber suspension left over after microfiltration can be used in food production, for example, as a thickening agent in the production of yogurts.
Combination of ground penetrating radar and seismic surveys of the tailings dam
Authors: Kalashnik A , Dyakov A
Published: December 2021

Identification of water-saturated zones in the tailings dams is an actual scientific and practical task in terms of providing, first of all, their mechanical strength and filtration stability. Use of active sounding geophysical study methods allows obtaining sufficiently detailed information about the peculiarities of the internal structure of the tailings dam and the degree of water saturation of the composing soils. The paper presents the results of in-situ experiments on the study of the tailings dam of the mining enterprise by ground penetrating radar (GPR) and seismic methods. A comparative analysis of the conducted studies has allowed clarifying the internal structure and assessing the dam’s condition, paying special attention to the identification of local zones of increased water saturation and filtration. Based on the calculated correlation coefficient of electromagnetic and seismic wave velocity values, it was revealed that synchronization of geophysical surveys allows significantly increasing the reliability of in-situ determinations, as well as obtaining more reliable data. The results of the studies are the basis for predicting the most vulnerable places (zones) of a bulk ground hydraulic facility, as well as the localization of water-saturated areas in the body of the ground structures with greater reliability and performance.
Asymmetric electrode geometry induced photovoltaic behavior for self-powered organic artificial synapses
Authors: Zou Shizan , Wang Hengyuan , Guo Jianhang , Jiang Sai , Hao Ziqian , Pei Mengjiao , Xu Xin , Li Yating , Chen Jiaming , Wang Junzhuan , Li Yun
Published: December 2021

Opto-electronic synapses have attracted considerable attention because of their promising potential in artificial visual perception systems for neuromorphic computing. Despite remarkable progress in mimicking synaptic functions, reduction of energy consumption of artificial synapses is still a substantial obstacle that is required to be overcome to promote advanced emerging applications. Herein, we propose a zero-power artificial optoelectrical synapses using ultrathin organic crystalline semiconductors, which can be self-driven by exploiting the photovoltaic effect induced by asymmetric electrode geometry contacts. The photogenerated charge carrier collection at the two electrodes is unbalanced due to the asymmetric contacts, leading to the in-plane current without bias voltage. Our devices successfully mimic a range of important synaptic functions, such as paired-pulse facilitation and spike rate-dependent plasticity. Furthermore, we demonstrate that our devices can realize the simulation of image sharpening under self-driven optical-sensing synaptic operations, offering prospects for the development of retinomorphic visual systems.
Dynamically corrected gates from geometric space curves
Authors: Barnes Edwin , Calderon-Vargas Fernando A , Dong Wenzheng , Li Bikun , Zeng Junkai , Zhuang Fei
Published: December 2021

Quantum information technologies demand highly accurate control over quantum systems. Achieving this requires control techniques that perform well despite the presence of decohering noise and other adverse effects. Here, we review a general technique for designing control fields that dynamically correct errors while performing operations using a close relationship between quantum evolution and geometric space curves. This approach provides access to the global solution space of control fields that accomplish a given task, facilitating the design of experimentally feasible gate operations for a wide variety of applications.
Transfer-tensor description of memory effects in open-system dynamics and multi-time statistics
Authors: Gherardini Stefano , Smirne Andrea , Huelga Susana F , Caruso Filippo
Published: December 2021

The non-Markovianity of an arbitrary open quantum system is analyzed in reference to the multi-time statistics given by its monitoring at discrete times. On the one hand, we exploit the hierarchy of inhomogeneous transfer tensors (TTs), which provides us with relevant information about the role of correlations between the system and the environment in the dynamics. The connection between the TT hierarchy and the CP-divisibility property is then investigated, by showing to what extent quantum Markovianity can be linked to a description of the open-system dynamics by means of the composition of one-step TTs only. On the other hand, we introduce the set of stochastic TT transformations associated with local measurements on the open system at different times and conditioned on the measurement outcomes. The use of the TT formalism accounts for different kinds of memory effects in the multi-time statistics and allows us to compare them on a similar footing with the memory effects present in non-monitored non-Markovian dynamics, as we illustrate on a spin-boson case study.
Robustly decorrelating errors with mixed quantum gates
Authors: Polloreno Anthony M , Young Kevin C
Published: December 2021

Coherent errors in quantum operations are ubiquitous. Whether arising from spurious environmental couplings or errors in control fields, such errors can accumulate rapidly and degrade the performance of a quantum circuit significantly more than an average gate fidelity may indicate. As Hastings (2017 Quantum Inf. Comput.
17 488) and Campbell (2017 Phys. Rev. A 95 042306) have recently shown, by replacing the deterministic implementation of a quantum gate with a randomized ensemble of implementations, one can dramatically suppress coherent errors. Our work begins by reformulating the results of Hastings and Campbell as a quantum optimal control problem. We then discuss a family of convex programs able to solve this problem, as well as a set of secondary objectives designed to improve the performance, implementability, and robustness of the resulting mixed quantum gates. Finally, we implement these mixed quantum gates on a superconducting qubit and discuss randomized benchmarking results consistent with a marked reduction in the coherent error.
Phase-modulated single-photon nonreciprocal transport and directional router in a waveguide–cavity–emitter system beyond the chiral coupling
Authors: Wang Xin , Yang Wen-Xing , Chen Ai-Xi , Li Ling , Shui Tao , Li Xiyun , Wu Zhen
Published: December 2021

We propose a potentially practical scheme for the controllable single-photon transport via waveguides which are coupled to a microcavity–emitter system. The microcavity–emitter system consists of a V-type three-level emitter and two or one single-mode microcavity. A driving field is used to drive a hyperfine transition between two upper excited states of the V-type three-level emitter. Beyond chiral coupling between waveguides and microcavity–emitter system, we show that the perfectly nonreciprocal single-photon transport in a single waveguide and the single-photon router with 100% routing probability in two waveguides can be achieved. Interesting enough, whether the nonreciprocal single-photon transport or the single-photon router can be switched periodically by adjusting the phase associated with microcavity–emitter coupling strength and the driving field. The complete physical explanation of the underlying mechanism is presented.
New physical parameterizations of monopole solutions in five-dimensional general relativity and the role of negative scalar field energy in vacuum solutions
Authors: Balytskyi Y , Hoyer D , Pinchuk A O , Williams L L
Published: December 2021

Novel parameterizations are presented for monopole solutions to the static, spherically-symmetric vacuum field equations of five-dimensional general relativity. First proposed by Kaluza, 5D general relativity unites gravity and classical electromagnetism with a scalar field. These monopoles correspond to bodies carrying mass, electric charge, and scalar charge. The new parameterizations provide physical insight into the nature of electric charge and scalar field energy. The Reissner-Nordström limit is compared with alternate physical interpretations of the solution parameters. The new parameterizations explore the role of scalar field energy and the relation of electric charge to scalar charge. The Kaluza vacuum equations imply the scalar field energy density is the negative of the electric field energy density for all known solutions, so the total electric and scalar field energy of the monopole is zero. The vanishing of the total electric and scalar field energy density for vacuum solutions seems to imply the scalar field can be understood as a negative-energy foundation on which the electric field is built.
Ultrafast carrier dynamics at organic donor–acceptor interfaces—a quantum-based assessment of the hopping model
Authors: Dorfner Maximilian F X , Hutsch Sebastian , Borrelli Raffaele , Gelin Maxim F , Ortmann Frank
Published: December 2021

We investigate the charge transfer dynamics of photogenerated excitons at the donor–acceptor interface of an organic solar cell blend under the influence of molecular vibrations. This is examined using an effective Hamiltonian, parametrized by density functional theory calculations, to describe the full quantum behaviour of the relevant molecular orbitals, which are electronically coupled with each other and coupled to over 100 vibrations (via Holstein coupling). This electron–phonon system is treated in a numerically quasi-exact fashion using the matrix-product-state (MPS) ansatz. We provide insight into different mechanisms of charge separation and their relation to the electronic driving energy for the separation process. We find ultrafast electron transfer, which for small driving energy is dominated by kinetic processes and at larger driving energies by dissipative phonon emission connected to the prevalent vibration modes. Using this fully quantum mechanical model we perform a benchmark comparison to a recently developed semi-classical hopping approach, which treats the hopping and vibration time scales consistently. We find qualitatively and quantitatively good agreement between the results of the sophisticated MPS based quantum dynamics and the simple and fast time-consistent-hopping approach.
Diffeomorphic shape evolution coupled with a reaction-diffusion PDE on a growth potential
Authors: Hsieh Dai-Ni , Arguillère Sylvain , Charon Nicolas , Younes Laurent
Published: December 2021

This paper studies a longitudinal shape transformation model in which shapes are deformed in response to an internal growth potential that evolves according to an advection reaction diffusion process. This model extends prior works that considered a static growth potential, i.e., the initial growth potential is only advected by diffeomorphisms. We focus on the mathematical study of the corresponding system of coupled PDEs describing the joint dynamics of the diffeomorphic transformation together with the growth potential on the moving domain. Specifically, we prove the uniqueness and long time existence of solutions to this system with reasonable initial and boundary conditions as well as regularization on deformation fields. In addition, we provide a few simple simulations of this model in the case of isotropic elastic materials in 2D.
Emergence of a periodically rotating one-point cluster in a thermodynamic Cucker-Smale ensemble
Authors: Cho Hangjun , Du Linglong , Ha Seung-Yeal
Published: December 2021

We study emergent behaviors of thermomechanical Cucker-Smale (TCS) ensemble confined in a harmonic potential field. In the absence of external force field, emergent dynamics of TCS particles has been extensively studied recently under various frameworks formulated in terms of initial configuration, system parameters and network topologies. Moreover, the TCS model does not exhibit rotating motions in the absence of an external force field. In this paper, we show the emergence of periodically rotating one-point cluster for the TCS model in a harmonic potential field using elementary energy estimates and continuity argument. We also provide several numerical simulations and compare them with analytical results.
A novel EZH2/NXPH4/CDKN2A axis is involved in regulating the proliferation and migration of non-small cell lung cancer cells
Authors: Yang Zeng , Wei Bo , Qiao Anbang , Yang Popo , Chen Wenhui , Zhen Dezhi , Qiu Xiaojian
Published: December 2021

NXPH4 is discovered to be a neuropeptide-like glycoprotein, belonging to the Neurexophilins (Nxphs) family. NXPH4 shares a similar domain structure with NXPH1, which, however, is poorly understood in terms of its function. Bioinformatics analysis and experimental verification in this study confirmed the abnormal high expression of NXPH4 in non-small cell lung cancer (NSCLC) tissues and cells. Knockdown of NXPH4 by siRNA can inhibit the proliferation and migration of cells, resulting in significant cell cycle arrest in S1 phase. Furthermore, in NSCLC cells, NXPH4 was regulated by transcriptional activation of enhancer of zeste homolog 2 (EZH2) in its upstream. While downstream, NXPH4 could interact with CDKN2A and downregulate its protein stability, thus participating in the cell cycle regulation through interacting with cyclinD-CDK4/6-pRB-E2F signaling pathway. To sum up, the present study reveals a regulatory pathway of EZH2/NXPH4/CDKN2A in NSCLC, providing possible reference for understanding the function of NXPH4 in tumors.
A ‘Mini Linguistic State Examination’ to classify primary progressive aphasia
Authors: Patel Nikil , Peterson Katie A. , Ingram Ruth U. , Storey Ian , Cappa Stefano F. , Catricala Eleonora , Halai Ajay , Patterson Karalyn E. , Lambon Ralph Matthew A. , Rowe James B. , Garrard Peter
Published: December 2021

There are few available methods for qualitatively evaluating patients with primary progressive aphasia. Commonly adopted approaches are time-consuming, of limited accuracy or designed to assess different patient populations. This paper introduces a new clinical test—the Mini Linguistic State Examination—which was designed uniquely to enable a clinician to assess and subclassify both classical and mixed presentations of primary progressive aphasia. The adoption of a novel assessment method (error classification) greatly amplifies the clinical information that can be derived from a set of standard linguistic tasks and allows a five-dimensional profile to be defined. Fifty-four patients and 30 matched controls were recruited. Five domains of language competence (motor speech, phonology, semantics, syntax and working memory) were assessed using a sequence of 11 distinct linguistic assays. A random forest classification was used to assess the diagnostic accuracy for predicting primary progressive aphasia subtypes and create a decision tree as a guide to clinical classification. The random forest prediction model was 96% accurate overall (92% for the logopenic variant, 93% for the semantic variant and 98% for the non-fluent variant). The derived decision tree produced a correct classification of 91% of participants whose data were not included in the training set. The Mini Linguistic State Examination is a new cognitive test incorporating a novel and powerful, yet straightforward, approach to scoring. Rigorous assessment of its diagnostic accuracy confirmed excellent matching of primary progressive aphasia syndromes to clinical gold standard diagnoses. Adoption of the Mini Linguistic State Examination by clinicians will have a decisive impact on the consistency and uniformity with which patients can be described clinically. It will also facilitate screening for cohort-based research, including future therapeutic trials, and is suitable for describing, quantifying and monitoring language deficits in other brain disorders.
Plasticity in the developing brain: neurophysiological basis for lesion-induced motor reorganization
Authors: Batschelett Mitchell , Gibbs Savannah , Holder Christen M. , Holcombe Billy , Wheless James W. , Narayana Shalini
Published: December 2021

The plasticity of the developing brain can be observed following injury to the motor cortex and/or corticospinal tracts, the most commonly injured brain area in the pre- or peri-natal period. Factors such as the timing of injury, lesion size and lesion location may affect a single hemisphere’s ability to acquire bilateral motor representation. Bilateral motor representation of single hemisphere origin is most likely to occur if brain injury occurs before the age of 2 years; however, the link between injury aetiology, reorganization type and functional outcome is largely understudied. We performed a retrospective review to examine reorganized cortical motor maps identified through transcranial magnetic stimulation in a cohort of 52 patients. Subsequent clinical, anthropometric and demographic information was recorded for each patient. Each patient’s primary hand motor cortex centre of gravity, along with the Euclidian distance between reorganized and normally located motor cortices, was also calculated. The patients were classified into broad groups including reorganization type (inter- and intrahemispheric motor reorganization), age at the time of injury (before 2 years and after 2 years) and injury aetiology (developmental disorders and acquired injuries). All measures were analysed to find commonalities between motor reorganization type and injury aetiology, function and centre of gravity distance. There was a significant effect of injury aetiology on type of motor reorganization (P < 0.01), with 60.7% of patients with acquired injuries and 15.8% of patients with developmental disorders demonstrating interhemispheric motor reorganization. Within the interhemispheric motor reorganization group, ipsilaterally and contralaterally projecting hand motor cortex centres of gravity overlapped, indicating shared cortical motor representation. Furthermore, the data suggest significantly higher prevalence of bilateral motor representation from a single hemisphere in cases of acquired injuries compared to those of developmental origin. Functional outcome was found to be negatively affected by acquired injuries and interhemispheric motor reorganization relative to their respective counterparts with developmental lesions and intrahemispheric motor reorganization. These results provide novel information regarding motor reorganization in the developing brain via an unprecedented cohort sample size and transcranial magnetic stimulation. Transcranial magnetic stimulation is uniquely suited for use in understanding the principles of motor reorganization, thereby aiding in the development of more efficacious therapeutic techniques to improve functional recovery following motor cortex injury.
Clinical spectrum of gross haematuria following SARS-CoV-2 vaccination with mRNA vaccines
Authors: Ritter Alexander , Helmchen Birgit , Gaspert Ariana , Bleisch Joerg , Fritschi Barbara , Buchkremer Florian , Damm Stephanie , Schmid Nicolas , Schachtner Thomas , Seeger Harald
Published: December 2021

Background

Novel messenger RNA (mRNA)-based vaccines play an important role in current vaccination campaigns against SARS-CoV-2. They are highly efficacious and generally well tolerated. Vaccination in patients with immune-mediated kidney diseases is recommended. A number of cases with de novo or relapsing glomerulonephritis shortly after vaccine application have been reported, some of which presented with gross haematuria.

Methods

We collected 10 cases of macrohaematuria following mRNA-based severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination at our tertiary care institution and referring centres. Additionally, we pooled all 25 published cases from the literature with ours to analyse their clinical characteristics.

Results

Most macrohaematuria episodes (72.2%) began within 2 days after vaccination, the majority after the second dose. In some individuals, repeated episodes occurred after subsequent doses of the same vaccine. A total of 65.7% of patients never had macrohaematuria before. A total of 45.7% were known to suffer from immunoglobulin A nephropathy (IgAN); the rest had no prior renal diagnosis. IgAN was the most frequent new diagnosis, but anti-neutrophil cytoplasmic antibody-associated vasculitis and anti-glomerular basement membrane disease were also identified. Acute kidney injury (AKI) occurred in 28.6% of patients, with an increase in serum creatinine not meeting Kidney Disease: Improving Global Outcomes AKI criteria in 28.6%. Treatment ranged from conservative management, renin–angiotensin–aldosterone system inhibitors, steroids and cyclophosphamide to plasmapheresis. While renal outcomes were mainly favourable in isolated IgAN, they were poor in patients with additional or isolated small vessel vasculitis.

Conclusion

Awareness of gross haematuria after SARS-CoV-2 vaccination is important. Close follow-up and additional work up, particularly in individuals without known underlying kidney disease or worsening renal function, is essential. For patients with vaccine-associated macrohaematuria, an alternative vaccine class might be considered for subsequent vaccinations.
Impact of COVID-19 on the Human Personality: An Analysis Based on Document Modeling Using Machine Learning Tools
Authors: Acharya Amitabha , Aryan Aman , Saha Sujay , Ghosh Anupam
Published: December 2021

Coronavirus disease of 2019 (COVID-19) has affected the globe terribly. The rapid spread of this virus and the precautionary measures to prevent it have impacted the lives of all human beings around the world in all dimensions. The anxieties over the virus along with the social restrictions have challenged the mental health and might have acute psychological consequences. In this study, our aim is to analyze whether COVID-19 has done any significant changes to very well-known five-factor personality traits of all the humans all over the world from social media text, such as Twitter. We first train and validate five machine learning models on the benchmark essays dataset and then those models are tested on the preprocessed Twitter dataset, consisting of pre_covid and post_covid tweets. The novelty of this study is to analyze and establish the fact that in this short period of time, COVID-19 cannot make very significant changes in the human personality all over the world. We have compared the performances of five machine learning models and what we have found is that the result provided by one model is also justified by the other models.
Can chronic anti-tumour necrosing factor therapy and colic polyps overwhelm a normal functioning mitral valve? A case report of an endocarditis complicated by a ruptured intracranial mycotic aneurysm
Authors: Khadir Karim , Mirica Daniela , Ligot Noémie , van de Borne Philippe
Published: December 2021

Background

Rapid identification of endocarditis is challenging but also an important opportunity to change disease course. This is especially true when immunosuppression undermines diagnosis by mitigating symptoms that commonly accompany infectious disease, sometimes in the absence of predisposing heart valve disease as in this case presented here.

Case summary

A middle-aged man with chronic etanercept treatment for ankylosing spondylitis, with previously well-documented normal cardiac valves, presented with afebrile chills, night sweating, weight loss, and a new mitral regurgitation at auscultation. This Streptococcus bovis-related endocarditis, in the presence of benign colic polyps, rapidly became complicated by a ruptured infectious intracranial mycotic aneurysm. The patient was successfully cured by endovascular embolization. Severe mitral regurgitation required an uneventful mitral annuloplasty 1 month thereafter.

Discussion

Immunosuppression from etanercept treatment was likely responsible for this unspecific clinical presentation and potentially devastating intracranial mycotic aneurysm. This complication is infrequently reported within 6 months of anti-tumour necrosing factor therapy initiation but occurred after more than 11 years of therapy in our patient. This case is a timely reminder of the clinical challenges of endocarditis in immunosuppressed patients and highlights a potential long-term complication of etanercept.
Caseous necrosis of the mitral annulus: a new feature of drug-induced valvular heart disease? Case series
Authors: Leblon Tiphaine , Riolet Clemence , Ennezat PierreVladimir , Marechaux Sylvestre
Published: December 2021

Background

Drug-induced valvular heart disease (DI-VHD) is a well-defined condition associated with specific pathology features. However, clinical presentations may broadly vary and thereby make DI-VHD diagnosis more challenging.

Case summary

We report two patients with a history of benfluorex administration, who developed extensive mitral calcific lesions which evolved towards caseous necrosis.

Discussion

Prospective follow-up over several years of these two patients who initially had typical DI-VHD findings provided monitoring evidence of extensive calcifications and subsequent caseous necrosis. These reports suggest a link between calcific heart injury and benfluorex exposure. The diagnosis of DI-VHD may be overlooked at this late stage.
Effect of an eLearning Memory Program on Reducing Negative Impact of Age-Related Memory Changes
Authors: Zhu Lynn , D'Amico Danielle , Yusupov Iris , Lass Jordan , Levine Brian , Vandermorris Susan , Troyer Angela
Published: December 2021

Age-related memory changes pose considerable concerns for aging adults, and can adversely affect their daily living and cause worry even when changes experienced are not clinically significant. The Memory and Aging Program® is a validated psychoeducation and memory strategy-training program that teaches the public about memory changes during aging and trains them to use evidence-based strategies to support brain health. The program has been offered in-person for over 20 years, and a self-guided eLearning version was recently developed to improve program accessibility. This study evaluated the self-reported impacts of memory changes in older adults who completed this eLearning against a control group. We randomized 202 older adults, without neurological or psychiatric diagnoses (71.6 years; 69 % female; 15.6 years of education), into the eLearning program or a control group that received no intervention. All participants reported their perceived impact of memory changes using the Memory Impact Questionnaire at pre-, post-, and 6-8 weeks follow-up. A significant reduction in negative impact of memory changes on daily living and a significant improvement in positive coping with memory changes relative to controls was observed at post-test (13.4 versus 2.5 points reduction and 7.4 versus 0.1 point improvement, respectively, both p < 0.05), but these did not persist at follow-up. The adoption of digital tools has hastened across all ages. Our study showed that self-guided digital tools, such as the eLearning Memory and Aging Program®, may be a promising avenue to help aging individuals reduce the impact of memory changes on daily living.