bluuebunny/crossref_metadata_2025 huggingface dataset:
A calibration method for rotary optical encoder temperature error in a rotational inertial navigation system
Authors: Ban Jingxuan , Chen Gang , Wang Lei , Meng Yue
Published: January 2022

A rotary optical encoder is an important component in a rotational inertial navigation system (RINS). It is used to form a closed-loop motor control system and calculate the system attitude. The system performance will be affected by the encoder’s error. Ín addition to the installation errors, the working temperature variants can lead to encoder error. Therefore, in this paper we propose a method to calibrate and compensate the temperature errors of rotary optical encoders. First, an independent testing mechanism with position limitation and a rotatable platform is designed and produced to verify the temperature influence on encoders. Then, the temperature error of the rotary optical encoder used in RINS is calculated by a gyroscope whose sensitive axis is parallel to the same motor axis. The method is verified by a self-researched single-axis RINS. According to the experimental results, the measurement accuracy is increased by more than 47.9% compared to the traditional method.
Modeling of the precipitation kinetics and morphology evolution of lamellar α in Ti-alloys during non-isothermal treatments
Authors: Liu Xueyan , Li Hongwei , Zhan Mei
Published: January 2022

The non-isothermal diffusional phase transformation plays an important role in adjusting materials microstructure. In the modeling of non-isothermal transformation, actual temperature history has a remarkable effect on the precipitation kinetics of new phase. When morphology anisotropy effect is considered, taking actual temperature history effect into account is very difficult for guaranteeing the accuracy of kinetics prediction. In order to solve this problem, a new non-isothermal transformation model in combination with cellular automaton (CA) method with mixed-controlled mode was proposed. In this new model, actual temperature history effect was characterized by the effects of cooling path and additive isothermal path on the nucleation and growth of new phase. Firstly, the cooling path with the consideration of supercooling effect was introduced into the created isothermal transformation theory model. Secondly, the temperature-time path (i.e. additive isothermal path) in CA model was calibrated by using the solute concentration model from experiments. With the use of this new model, the precipitation kinetics and morphology evolution of the lamellar α for IMI834 titanium alloy during continuous cooling from single-phase region was predicted. The predicted results were in good agreement with experiments. It was also revealed that the dominant role of mixed-controlled mode for lamellar α precipitation was gradually changed from the diffusion control to the interface control with the increase of cooling rate.
Photothermal methane coupling into liquid fuels with hydrogen evolution over nanocatalysts based on layered double hydroxide (LDH)
Authors: Zhao Jiaqing , Shi Run , Zhang Xuerui , Wang Zeping , Zhang Tierui
Published: January 2022

The increasing energy and environmental problems have made clean energy-driven catalysis a hot research topic. Methane is an earth-abundant raw material but difficult to be converted by thermochemical processes. It is of great significance to seek novel strategies to convert methane into high-value chemicals. Herein, we synthesize a series of transition metal catalysts based on layered double hydroxide precursors which were used for photothermal methane nonoxidative coupling reactions. The strong photothermal and chemisorption effects of the derived transition metal nanostructures allow the efficient activation of methane molecules. Among them, alumina-supported metallic Ni and NiCo-alloy catalysts show excellent methane nonoxidative coupling activities, achieved hydrogen production rates of 4816.53 μmol g−1 h−1 and 5130.9 μmol g−1 h−1, accompanied by liquid fuels production rates of 59.2 mg g−1 h−1 and 63 mg g−1 h−1, respectively. The findings, therefore, provide a new strategy for methane nonoxidative coupling driven by light energy at mild conditions.
Incompatible case of perfect conductor approximation in vacuum nonlinear electromagnetism
Authors: Shibata Kazunori
Published: January 2022

The perfect conductor approximation is the most practical way to treat light reflection by a mirror. We demonstrate that the approximation and nonlinear electromagnetism in vacuum are not always compatible. In the presence of external magnetic flux density, we prove that there is no solution for the nonlinear Maxwell’s equations if a perfect conductor mirror is folded by 90 degrees. Demonstrated results show that the perfect conductor approximation can be inappropriate. We also suggest an approach to avoid the incompatibility.
Primordial Weibel instability
Authors: Mirón-Granese Nahuel , Calzetta Esteban , Kandus Alejandra
Published: January 2022

We study the onset of vector instabilities in the post-inflationary epoch of the Universe as a mechanism for primordial magnetic fields amplification.
We assume the presence of a charged spectator scalar field arbitrarily coupled to gravity during Inflation in its vacuum de Sitter state. Gravitational particle creation takes place at the transition from Inflation to the subsequent Reheating stage and thus the vacuum field state becomes an excited many particles one.
Consequently this state can be described as a real fluid, and we build out the hydrodynamic framework using second order theories for relativistic fluids with a relaxation time prescription for the collision integral.
Given the high-temperature regime and the vanishing scalar curvature of the Universe during Reheating (radiation-dominated-type era), the fluid can be regarded as a conformal one.
The large quantum fluctuations induced by the rapid transition from inflationary to effectively radiation dominated expansion become statistical fluctuations whereby both a charge excess and anisotropic pressures are produced in any finite domain. The precise magnitude of the effect for each scale is determined by the size of the averaging domain and the coupling to curvature. We look at domains which are larger than the horizon at the beginning of Reheating, but much smaller than our own horizon, and show that in a finite
fraction of them the anisotropy and charge excess provide suitable conditions for a Weibel instability. If moreover the duration of reheating is shorter than the relaxation time of the fluid, then this instability can compensate or even overcome the conformal dilution of a primordial magnetic field. We show that the non-trivial topology of the magnetic field encoded in its magnetic helicity is also amplified if present.
Ladder symmetries of black holes. Implications for love numbers and no-hair theorems
Authors: Hui Lam , Joyce Austin , Penco Riccardo , Santoni Luca , Solomon Adam R.
Published: January 2022

It is well known that asymptotically flat black holes in general
relativity have a vanishing static, conservative tidal response. We show that this is a result of linearly realized symmetries governing
static (spin 0,1,2)
perturbations around black holes. The symmetries have a geometric origin: in the scalar case, they arise from the (E)AdS isometries of a dimensionally reduced black hole spacetime. Underlying the symmetries is a ladder structure which can be used to construct the full tower of solutions,
and derive their general properties: (1) solutions that decay with
radius spontaneously break the symmetries, and must
diverge at the horizon;
(2) solutions regular at the horizon respect the symmetries, and
take the form of a finite polynomial that grows with radius.
Taken together, these two properties imply that static response coefficients — and in particular Love numbers — vanish. Moreover, property (1) is consistent with the absence of black holes with linear (perturbative) hair. We also discuss the manifestation of these symmetries in the effective point particle description of a black hole, showing explicitly that for scalar probes
the worldline couplings associated with a non-trivial tidal response and scalar hair must vanish in order for the symmetries to be preserved.
Predictions for local PNG bias in the galaxy power spectrum and bispectrum and the consequences for f
NL constraints
Authors: Barreira Alexandre
Published: January 2022

We use hydrodynamical separate universe simulations with the IllustrisTNG model to predict the local primordial non-Gaussianity (PNG) bias parameters b
ϕ and b
ϕδ, which enter at leading order in the galaxy power spectrum and bispectrum. This is the first time that b
ϕδ is measured from either gravity-only or galaxy formation simulations. For dark matter halos, the popular assumption of universality overpredicts the b
ϕδ(b
1) relation in the range 1 ≲ b
1 ≲ 3 by up to Δ b
ϕδ ∼ 3 (b
1 is the linear density bias). The adequacy of the universality relation is worse for the simulated galaxies, with the relations b
ϕ(b
1) and b
ϕδ(b
1) being generically redshift-dependent and very sensitive to how galaxies are selected (we test total, stellar and black hole mass, black hole mass accretion rate and color). The uncertainties on b
ϕ and b
ϕδ have a direct, often overlooked impact on the constraints of the local PNG parameter f
NL, which we study and discuss. For a survey with V = 100 Gpc3/h3 at z=1, uncertainties Δ b
ϕ ≲ 1 and Δ b
ϕδ ≲ 5 around values close to the fiducial can yield relatively unbiased constraints on f
NL using power spectrum and bispectrum data. We also show why priors on galaxy bias are useful even in analyses that fit for products f
NL
b
ϕ and f
NL
b
ϕδ. The strategies we discuss to deal with galaxy bias uncertainties can be straightforwardly implemented in existing f
NL constraint analyses (we provide fits for some of the bias relations). Our results motivate more works with galaxy formation simulations to refine our understanding of b
ϕ and b
ϕδ towards improved constraints on f
NL.
Research on α-decay for the superheavy nuclei with Z= 118–120 *
Authors: He Chen , Niu Zhong-Ming , Bao Xiao-Jun , Guo Jian-You
Published: January 2022

The generalized liquid-drop model (GLDM) with the microscopic shell correction from relativistic Hartree-Fock (RHF) calculations is used to explore the α-decay of superheavy nuclei. The known nuclei with

are chosen as examples for testing. The calculated half-lives of α-decay agree with the experimental data better than those from the GLDM with the shell correction in the Weizs

cker-Skyrme model. Moreover, the influence of the decay energy

on α-decay is investigated. It is determined that the

values obtained from the WS4 model with radial basis function (RBF) correction match the experimental data optimally. Owing to these advantages, the GLDM with the RHF shell correction and WS4+RBF

values is adopted to predict the α-decay lifetime for the unknown superheavy nuclei with

. The trend of the available α-decay half-lives according to the neutron number is similar to the trends of the values from the GLDM calculation without shell correction as well as the universal decay law (UDL) formula. Comparably, the RHF shell correction depresses (raises) the α-decay lifetime for most nuclei with

(

). In comparison with the half-lives of spontaneous fission, it can be concluded that the α-decay is dominant in the superheavy nuclei

,

, and

. These results are beneficial to the exploration of superheavy nuclei in experiments.
The role of defects, deuterium, and surface morphology on the optical response of beryllium
Authors: Minissale M. , Louis De Canonville C. , Pardanaud C. , Butoi B. , Bisson R. , Gallais L.
Published: January 2022

The knowledge of optical properties of beryllium is of crucial importance in fields such as nuclear fusion and aerospace applications. The optical properties of pure beryllium are known in the visible and infrared domains. Nevertheless, the role of different physico-chemical parameters such as composition and surface roughness, that is often neglected in first approximation, deserves dedicated comprehensive studies. In this work we have studied the optical properties of bulk beryllium and magnetron sputtering beryllium layers in the 500–2000 nm spectral range. Experimental measurements show that beryllium reflectivity strongly depends both on bulk fabrication procedure and on surface preparation. Different models allow us to perform a quantitative interpretation of reflectivity results and to study the influence of different parameters: (i) a multi-reflection interference model to understand the role of oxide layer, (ii) a Lorentz–Drude model for the bulk composition effect, (iii) scattering models for the surface roughness, and (iv) the Maxwell–Garnett model for the surface porosity. The calculated relative permittivity of the studied samples is used to evaluate the emissivity in the visible and infrared domain. Such evaluation, giving indications of possible evolution of optical properties of beryllium in a plasma environment, can provide a useful tool for thermography studies of tokamak walls.
Analysis and Improvement of the Q-iteration Method
Authors: Zhang Z H , Zeng S , Jiang D J
Published: January 2022

The q-iteration method is simple, efficient and robust in determining the concentration distribution in an isotope separation cascade with a known hydraulic state. The expression of the quantity q and the value of the relaxation factor of the q-iteration method have a significant influence on the convergence rate of iteration. Through analyzing the convergence of the q-iteration method, an improved method for updating q is proposed, and the value range of the relaxation factor is obtained. Numerical analysis shows that the improved method can significantly speed up the convergence. By selecting an appropriate value of the relaxation factor, the convergence can be further improved.
Comparison of the efficiency of square cascades with an additional product flow and double cascades to concentrate intermediate isotopes
Authors: Azizov T E , Smirnov A Yu , Sulaberidze G A
Published: January 2022

Original techniques were proposed for calculating and optimizing double cascades (DC) built of square cascades and a square cascade with an additional product flow (SCAP). Both cascade schemes (DC and SCAP) were tested in solving a task of simultaneous enrichment of three components of a model mixture to a pre-defined level. A comparison of the DC and SCAP efficiency was made according to the minimum of total cascade flow. The results have shown that the double cascade is more efficient in terms of the chosen criterion.
A novel cascade optimization method based on butterfly optimization algorithm
Authors: Sun W , Zhou M S , Pan J X , Wang Y B
Published: January 2022

The parameter optimization of a multi-component isotope separation cascade is a multi-dimensional problem, involving many variables such as cut for stages, feed stage and separation factors. In this paper, a novel metaheuristic algorithm called butterfly optimization algorithm (BOA) is applied for the first time in cascade optimization field. Different objective functions are introduced like D function and a combination of D function and total flow rates. BOA method solves the problem of a 20-stage square cascade optimization to separate Xenon isotopes with the aim of getting the greatest D value or the least flow rates. The optimization results show that the optimal cut is close to the sum of the concentrations of the lightest N′C
isotopes. A 21-stage step cascade is optimized as well to obtain the best working conditions to separate 72Ge and the cut θ is consistent with the experiment results. The calculation results indicate that BOA shows good performance in terms of calculation stability, speed and convergence to global optimum compared with traditional optimization methods and other metaheuristic algorithm like TLBO.
Dysprosium enrichment and collection using AVLIS in Brazil: Preliminary results
Authors: Jakutis Neto J , Bueno P , dos Santos J R , da Silveira C A B , Rodrigues N A S , Victor A R , Destro M G , Neri J W
Published: January 2022

Rare Earth elements (RE) play an important role in the high-tech industry. Displays, fine electronic devices, sensors, optoelectronics, and many other fields rely on the use of these elements to deliver the technology we depend on. The possibility of improving the capacity of all these applications is attractive and there are a few ways to achieve that, one of them is to purify the REs to get only one isotope. Given that, one of the few techniques able to separate RE isotopes is the Atomic Vapor Laser Isotope Separation (AVLIS) which is the technique used in the Brazilian facility for isotope separation via laser. In this work we are going to show the latest results on the Brazilian AVLIS applied to enrich dysprosium. As a preliminary result, it was observed an enrichment by means of a mass spectrometer coupled to the experimental setup and a thin film was collected with an enrichment factor of 1.37 (163Dy).
Design of Gas Diffusion Cascade for Production of Carbon Isotope Using Ethylene as Processing Gas
Authors: Li Jun-Jie , Pan Jian-Xiong , Zhou Ming-Sheng , Pei Gen
Published: January 2022

Carbon-13 isotope has a wide range of applications in medical diagnosis, scientific research, food safety and other fields, and the market demand for carbon-13 isotope is also showing an upward trend. In order to explore the separation and production methods of carbon-13 isotope, the gas diffusion separation experiment with ethylene as the processing gas was carried out, and the cascade was designed on this basis. Through the single-stage separation experiment, it can be obtained that the overall separation factor of the gas diffusion method for separating ethylene under the existing experimental conditions is 1.014. The gas diffusion cascade enrichment of carbon-13 isotope involves two steps. The first step is to separate ethylene using a squared-off cascade to obtain the heavy fraction with the carbon-13 isotope abundance reaching 49%. The second step is to convert ethylene into carbon dioxide, and then use a squared-off cascade to separate the carbon dioxide to obtain the heavy fraction with the carbon-13 isotope abundance reaching 95%.
Power grid data fusion based on block chain technology
Authors: Yin LZ , Han XW , Gao CJ , Zhang J , Li Z
Published: January 2022

In order to improve the efficiency of power grid data processing, a new power grid data fusion method based on block chain model is proposed in this paper. The results show that the power grid data fusion method based on block chain technology has higher efficiency.
Study on Construction Technology of Bridge Structure Based on Oblique Photography
Authors: Xu N , Zhang X , Zhao JL
Published: January 2022

Based on the new technology of oblique photography, a real scene model of the building site is established. Construction simulation and traffic diversion design of bridge structure under the real scene model are studied. It is shown that the three-dimensional real scene model can reflect the environment of the bridge structure truly, and it provides a reasonable plan for the position of construction machinery and the organization of bridge demolition and construction, and it also provides a foundation for the efficient and orderly construction of the bridge structure.
The Bilevel Linear Programming with Fuzzy Relation Constraints
Authors: Xia DC
Published: January 2022

Aiming at the particularity of bilevel linear programming model with fuzzy relationship constraints, a new algorithm is designed based on bilevel linear programming. Firstly, a bilevel linear programming problem model with fuzzy relation constraints is established, and the related definitions are given; Then, the solution process of the model is stated. Finally, an example is given to verify the correctness of the algorithm.
An Experimental Study of the Impact Damage of Reinforced Concrete Piers Protected by Closed-Cell Aluminum Foam
Authors: Zhang WC , Jia LJ , Zhou XW
Published: January 2022

In recent years, China’s ship transportation has shown a rapid growth trend, and the accidents of ships hitting bridge piers are becoming more and more frequent. In view of the frequent occurrence of ships hitting bridge piers, this paper selects closed-cell aluminum foam as the anti-collision material of the piers, and conducts cumulative horizontal impact tests on the closed-cell aluminum foam protected concrete piers. The aim of the experimental tests was to study the influence of the stress stage, thickness and density change of the closed-cel laluminum foam on the impact damage of the concrete piers. The test results show that under the cumulative impact, the close-cell aluminum foam at the yield plateau stage can reduce the damage of the pier; the suitable thickness and density of closed-cell aluminum foam can slow down the development of pier cracks and reduce the impact damage of concrete piers; the densification, excessive thickness and density of closed-cell aluminum foam will increase the impact damage of the bridge pier.
Experimental Study of Basic Mechanical Properties of Short Basalt Fiber Bundle Reinforced Concrete
Authors: Shao JG , Wang S , Liu Y , Zhang P , Tang GB , Jin YG , Li CC
Published: January 2022

In this paper, the mechanical properties of basalt short fiber bundle reinforced concrete (sbfbrc) are designed, and the effects of basalt fiber bundle content and diameter on its compression, splitting and bending properties are studied. The results show that basalt fiber bundle has good dispersion in concrete. The splitting tensile strength and flexural strength of high-strength concrete are significantly improved, but the compressive strength is not significantly improved. The compressive strength of concrete increases first and then decreases. When the fiber bundle content is 0.2%, the compressive strength increases by 6.11%. The splitting tensile strength and bending strength increase with the increase of fiber bundle content. When the fiber bundle content was 0.6%, they increased by 19.54% and 20.32% respectively compared with the reference group. Compared with basalt fiber bundle with diameter of 0.5mm and 0.8mm respectively, basalt fiber bundle with diameter of 0.2mm has better effect on improving the compressive, splitting, tensile and flexural properties of concrete
Effectiveness of In-Service Dampers over Long-Term Operation for Cable Vibration Suppression: A Study Based on Field Testing
Authors: Zhou P , Liu M , Kong WM , Xu YM , Li H
Published: January 2022

In order to explore the operation mechanism of dampers used on super long-span bridges, the characteristics of dampers in long-term operation are studied through field tests. Firstly, viscous damper and liquid leakage MR damper are selected to test the influence of fluid connecting rod on its damping force; Then, wireless and wired sensors are used to collect the acceleration response of cables with viscous dampers and MR dampers. Finally, the vibration characteristics of the cable are analyzed, and the control performance of the selected damper is evaluated. The results show that the high-order multi-modal vibration of the cable will occur in the range of 2-6hz whether the damper is installed or not. In addition, fluid leakage may reduce the additional modal damping ratio achieved by MR damper.
Shear Performance of Interface between Polyvinyl Alcohol Fiber Engineered Cementations Composite (PVA-ECC) and Concrete: Analysis and Parametric Study
Authors: Liu HB , Li Y , Liu XP , Wang XT , Zhang SL , Han Y , Jiang ZQ
Published: January 2022

In this paper, the shear properties of the interface between polyvinyl alcohol fiber cement-based composites (pva-ecc) and concrete with different roughness are studied. The test results show that: 1. Z-type interface can effectively improve the shear performance of pva-ecc and old concrete; 2. With the increase of roughness, the slip peak value increases, and the horizontal extension section under failure shear stress is also longer; 3. The shear strength of the four types of interfaces is directly proportional to their roughness, but lower than the shear strength of the concrete itself.
Corrosion Factors and Mechanisms of Buffer Layer and Aluminum Sheath Inside High-Voltage Cable
Authors: Wang Xiaofeng , Ma Tao , Ma Xiao , Li Yongfu , Gao Chao , Hu Songling
Published: January 2022

Frequent failures of the buffer layer in high-voltage cables have been reported in recent years, which causes great losses. White spots and ablation were found inside these fault cables. The mechanisms of such failure phenomenon are still unclear, which arouses great attention of researchers. On the basses of previous studies, the authors characterized the fault cable, and studied the influence of the voltage type, moisture distribution, pressure, the shape of aluminum sheet on the generation of white spots. The authors proved the complexation of the water blocking powder and aluminum ions by using EDS (Energy Dispersive Spectroscopy). This paper provides meaningful theoretical supports for the design of new longitudinal water blocking structures.
Influence of SO2 in the Medium to High Temperature Range of SO3 Removal by CaO
Authors: Zhao Jiarui , Wang Zihao , Liu Youlong , Meng Fanqi , Shan Sike , Huang Chen , Liu Zhong
Published: January 2022

Injecting sorbents can effectively decrease the SO3 pollution, but its removal efficiency is reduced by the absorption owning to the abundant SO2. Experiments were carried out on a fix bed reacter to study the effect of SO2 on the deSO3 by CaO in the medium to high temperature range. The increase in temperature may obviously improve the removal efficiency of SO3, but the conversion of SO2 to CaO is much higher than SO3, resulting the SO3 selectivity decreases. Decreasing the SO2 concentration or increasing the SO3 concentration may increase conversion by CaO and SO3 selectivity, but the former is less influential than the latter.
Study on the Highly Efficient Reduction of CO2 to Formate Using Zinc under Mild Hydrothermal Conditions
Authors: Zeng Xu , Yao Guodong , Zhao Jianfu
Published: January 2022

In this study, the reaction mechanism of CO2 reduction by using Zn under mild hydrothermal condition was investigated by DFT calculation method. Based on the calculation of the transition state, as well as the IRC and HOMO/LUMO, the Zn-H was considered as a key intermediate for the high formate production from CO2. This study provides information on the reaction pathway of metal reduction with the metal hydrogen bond under hydrothermal conditions. The energy diagram showed that the Zn-H has high reducing activity, which induced that the formate was easily produced through hydrothermal reactions. From the viewpoint of energy, in the CO2 reaction system, the HCOO- was easily produced than that in the HCO3
- reaction system. This process provides new concept for the high efficient production of value-added chemicals in the carbon dioxide utilization research area.
Study on Friction and Wear Behaviors of M42 High Speed Steel
Authors: Liu Yu , Li Dong , Shao Qingli , Ma Haikun , Kang Jie , Su Ru
Published: January 2022

Taking Chinese-made (C-M42) and Japanese-made (J-M42) high-speed steel as research objects, the friction and wear tests were carried out and the wear mechanism was analysed. The microstructure and hardness of the two steels were observed by means of scanning electron microscope and hardness tester. Results show that J-M42 steel possesses a better wear resistance than C-M42 steel. This is related to relatively higher hardness, smaller average carbide size and higher volume fraction of carbide. There exists groove, adhesive patch and oxide layer in the worn surface. It manifests that the wear mechanisms of the two samples are adhesive wear, abrasive wear and slight oxidation wear. The overall surface roughness after wear is similar between the two steels whereas the plastic deformation layer in the vertical section of J-M42 steel is shallower than that of C-M42 steel.
VerDAQ: a Versatile Data AcQuisition system for high energy physics experiments
Authors: Rojas R. , Kuleshov S.V. , Silva C. , Carvajal G. , Abusleme A. , Hakobyan H. , Arredondo V. , Gonzalez J.
Published: January 2022

The Versatile Data AcQuisition (VerDAQ) system is a modular and flexible data acquisition platform designed to be used in a wide range of high-energy physics experiments, from small desktop detectors to large experiments in accelerators.
The main characteristic of VerDAQ is its flexibility that stems from a modular design, separating the front-end electronics in a mezzanine board from the back-end electronics on a motherboard. The latter includes a programmable System-on-Chip (SoC) that provides preprocessing and communication capabilities.

The VerDAQ system is hardware and firmware reconfigurable, enabling its use in standalone instruments as well as integrated into extensive data acquisition systems.
In this paper, the system structure is described in detail, and a particular implementation of a laboratory prototype using the DRS4 chip is characterized and used to demonstrate standalone operation.
Biomaterials-assisted exosomes therapy in osteoarthritis
Authors: Chen Manyu , Wang Qiguang , Wang Yunbing , Fan Yujiang , Zhang Xingdong
Published: January 2022

Due to the avascular characteristic of articular cartilage, its self-repair capacity is limited. When cartilage is damaged or forms osteoarthritis (OA), clinical treatment is necessary. However, conventional treatments, including joint replacement, microfracture, cell and drug therapies, have certain limits. Lately, the exosomes derived from mesenchymal stem cells (MSCs-EXO), which consist of complex transcription factors, proteins and targeting ligand components, have shown great therapeutic potentials. With recent advancements in various biomaterials to extend MSCs-EXO’s retention time and control the release properties in vivo, biomaterials-assisted exosomes therapy has been soon becoming a practically powerful tool in treating OA. This review analyzes the effects of MSCs-EXO on OA inflammation, metabolism, ageing and apoptosis, and introduces the combinational systems of MSCs-EXO with biomaterials to enhance the repair, anti-inflammatory, and homeostasis regulation functions. Moreover, different types of natural or synthetic biomaterials and their applications with MSCs-EXO were also described and discussed. And finally, we presage the future perspective in the development of biomaterial-assisted exosome therapies, as well as the potential to incorporate with other treatments to enhance their therapeutic effects in OA.
Siberian taiga and tundra fire regimes from 2001–2020
Authors: Talucci Anna C , Loranty Michael M , Alexander Heather D
Published: January 2022

Circum-boreal and -tundra systems are crucial carbon pools that are experiencing amplified warming and are at risk of increasing wildfire activity. Changes in wildfire activity have broad implications for vegetation dynamics, underlying permafrost soils, and ultimately, carbon cycling. However, understanding wildfire effects on biophysical processes across eastern Siberian taiga and tundra remains challenging because of the lack of an easily accessible annual fire perimeter database and underestimation of area burned by MODIS satellite imagery. To better understand wildfire dynamics over the last 20 years in this region, we mapped area burned, generated a fire perimeter database, and characterized fire regimes across eight ecozones spanning 7.8 million km2 of eastern Siberian taiga and tundra from ∼61–72.5° N and 100° E–176° W using long-term satellite data from Landsat, processed via Google Earth Engine. We generated composite images for the annual growing season (May–September), which allowed mitigation of missing data from snow-cover, cloud-cover, and the Landsat 7 scan line error. We used annual composites to calculate the difference Normalized Burn Ratio (dNBR) for each year. The annual dNBR images were converted to binary burned or unburned imagery that was used to vectorize fire perimeters. We mapped 22 091 fires burning 152 million hectares (Mha) over 20 years. Although 2003 was the largest fire year on record, 2020 was an exceptional fire year for four of the northeastern ecozones resulting in substantial increases in fire activity above the Arctic Circle. Increases in fire extent, severity, and frequency with continued climate warming will impact vegetation and permafrost dynamics with increased likelihood of irreversible permafrost thaw that leads to increased carbon release and/or conversion of forest to shrublands.
Predictive simulation of spring development of Cydalima perspectalis Walker in the South of Russia
Authors: Korsakova S P , Plugatar Y V , Sharmagiy A K
Published: January 2022

The work presents the results of a study of the features of the seasonal development of a dangerous invasive insect the box tree moth, Cydalima perspectalis Walker, specialised on plants of the genus Buxus L. Models for forecasting the dates of the resumption of larvae activity in spring after the winter diapause, the first adult flights of the overwintered generation and the appearance of the first summer generation of larvae have been developed for the southern regions of Russia. The accuracy of the forecast of the larvae coming out of the winter diapause is 3-4 days, of the adult flights and the appearance of the first summer of larvae is 9-10 days. The developed models can be used as a tool to improve the control of this pest.
IoT-based agriculture monitoring platform architecture
Authors: Zorkin A , Ivanova N
Published: January 2022

The research is aimed at solving one of the most urgent tasks of our time: the development of reliable and scalable software for monitoring the climate of agricultural fields. The goal is to create an architecture of simple and universal systems for collecting and storing data from various measuring devices located on agricultural land. The methodological basis for the monitoring system is the “Internet of Things” (IoT) approach. The agro-industrial complex of the Tomsk region (Russia) was chosen as a model object. About a hundred measuring devices have been installed in agricultural fields, which provide continuous delivery of data series in real time. Our developed platform includes both the server part of the application that processes and stores these weather data, and a convenient user interface for visualizing data to agronomists. The results of the research can be used in designing the architecture of similar IoT-based monitoring systems.
Features of Betula spp. cultivation through in vitro culture
Authors: Sergeev R , Kleva O , Timakov A , Zontikov D , Khusainova A
Published: January 2022

Birch improves the resilience of forests by colonizing forest gaps and rapidly increasing soil functioning and biodiversity [1], the healing properties of birch bark and extracts of birch bark have long been known in folk medicine around the world [2], and some species of birch are traditionally used to treat various inflammatory diseases [3], therefore, there is a need for high-quality birch planting material using clonal micropropagation. As a result of the study, data were obtained reflecting the dependence of the morphological parameters of plants on the content of the vitamin component and the composition of the nutrient medium. The study used culture media MS, WPM and QL without hormones and culture media MS, WPM and QL without hormones and vitamins. The most intense growth of shoots and leaves of the two studied clones was observed on WPM medium. The MS culture medium was used as a control.
State regulation of investment in agriculture
Authors: Lysa Olena , Oleksenko Roman , Azhazha Maryna , Venger Olga , Sergiienko Tetiana
Published: January 2022

An important task of state regulation of investment in the agricultural sector of the economy is to attract investors who are able to increase the efficiency of the functioning of agricultural enterprises. The success of the functioning of this enterprise depends on how quickly an agricultural enterprise is able to adapt to changes in the external environment. This is achievable under the condition of the most optimal use of the enterprise’s resource potential. Small agricultural enterprises are usually deprived of the possibility of using highly productive innovative agricultural technologies in their activities due to their high cost. Farm enterprises are also experiencing difficulties with insurance and attracting bank loans. In the competition with large agricultural enterprises, small farms survive mainly thanks to state subsidies. Large agricultural holdings are more financially stable, their economic activities are more diversified compared to farms. At large agricultural enterprises, labor productivity is higher and the cost of production is lower. The main task of the state for ensuring food security is to facilitate the process of consolidation of agricultural enterprises. The liquidation of small farming enterprises is an objective process that results from free market competition. The consolidation of agricultural enterprises will allow more efficient use of agricultural land in agricultural production.
Changes in work heaviness and intensity at farms with robotics
Authors: Semin A N , Skvortsov E A , Skvortsova E G
Published: January 2022

The article discusses the problems of changing the essence of work of agricultural workers in the context of introduction of digital technologies. The research aims to study the changes in heaviness and intensity of work of agricultural workers as a result of introduction of digital technologies. As research methods, the workplace of a robotic milking operator was assessed in comparison with a machine milking operator. And 7 indicators belong to class 1 and 6 indicators to the second class of the working conditions, therefore, a general assessment of work heaviness corresponds to the class “Acceptable” (class 2). The assessment of work intensity revealed 7 indicators that belong to class 3.1 (stressful work of the first degree) and 3 indicators to class 3.2 (stressful work of the second degree). This allows making a conclusion that a general assessment of work intensity of a robotic milking operator corresponds to the class of stressful work of second degree. The use of robotic milking can be recommended to reduce the loads for livestock workers. At the same time, attention should be paid to reducing the work intensity of robotic milking operators.
Development of a geoinformation atlas of the sanitary and chemical state of water sources in the arid region
Authors: Kosarev A V , Kosheleva I S , Chekmizov V A , Pankratova Yu A , Mikerov A N
Published: January 2022

The paper considers the development of a geoinformation atlas of the sanitary and chemical state of water sources in the arid region on the example of the Saratov region. The atlas summarizes the results of sanitary and chemical monitoring of surface and underground water sources in the Saratov region. Graphs of content of priority pollutants excess, as well as non-carcinogenic risk and hazard index for 2015-2021 are summarized in the form of an information map of a water source linked to its geographical coordinates. The atlas file system includes four blocks, each of which summarizes information about the hygienic condition of one of the types of water sources: springs, wells, small rivers, and sampling points on the Volga River. Atlas data can be derived using landscape models that allow to link the spatial position of a water source with the characteristics of its chemical composition, as well as output data in the form of a altitude diagram. The ratio between sanitary and hygienic indicators in dynamics can also be visualized in the form of diagrams. The atlas may be of interest to specialists in the field of preventive medicine and employees of research organizations dealing with environmental hygiene.
Modern trends in developing robotic systems in agro-industrial complex
Authors: Fedorov D E
Published: January 2022

The article is devoted to the issue of developing robotic systems in crop and livestock production. The author considers the trends in the improvement of robotic units used in the agro-industrial complex. In crop production, robots are used, as a rule, to perform such operations as sowing seeds, applying fertilizers, precise spraying of plants, monitoring the crop state, controlling weeds, and harvesting crops. The main directions of the robotic system development in agriculture are identified: in the field of crop production, they include increasing the versatility of aggregates, the accuracy of identifying fruits and plants during their treatment and harvesting, increasing the degree of the robotic systems’ autonomy including the use of solar panels, as well as, increasing the speed of performing working operations; in the field of animal husbandry - the development of technologies for “precision livestock farming”, automation and digitalization of all technological operations, providing comfortable conditions for farm animals.
Influence of climatic indicators on the dynamics of the growing season duration and forecasting vegetable peas’ harvest date
Authors: Besedin A G , Putina O V
Published: January 2022

The aim of the study was to determine the variability of climatic factors, to assess their influence on the yield and the duration of interfacial periods of vegetable pea varieties. The experiment was carried out from 2000 to 2019. 4 varieties with shrunken seeds of different ripening groups were studied. For interfacial periods, the sum of effective temperatures above 4.4 °C (ET), the sum of heat units from 4.4 °C (HU), the sum of active temperatures above 10 °C (SAT), the sum of precipitation (SP), the hydrothermal coefficient (HTC), the number of days with temperatures above 30 °C (T>30 ° C), with precipitation from 1 to 20 mm/day (1<P, mm<20) and with precipitation over 20 mm/day (P, mm>20) were calculated. In the south of Russia, the yield of vegetable peas is limited by precipitation frequency (from 1 mm to 20) on the days from sowing to technical ripeness. The studied parameters of environmental conditions characterizing the provision of moisture (HTC, SP, 1<P, mm<20, P, mm>20) and the number of days with T>30°C have a high level of variability. The number of days from sowing to sprouting and SAT of the “sprouting-technical ripeness” period are stable traits recommended for predicting the harvesting date of vegetable peas. A significant reduction in the growing season and its components was established in varieties of medium and late ripening when comparing modern (2000-2019) and earlier data (1964-1990). The results obtained indicate climatic changes, in connection with which it becomes necessary to use earlier varieties in production.
The study of the advantages and limitations, risks and possibilities of applying precision farming technologies
Authors: Gusev A , Skvortsov E , Sharapova V
Published: January 2022

The introduction of precision farming technologies at agricultural organizations in Russia is proceeding at a slow pace, that makes it necessary to find ways to intensify this activity. The study aims to identify opportunities, threats, strengths and weaknesses and develop scientific and practical recommendations on strengthening the use of precision farming technologies in agriculture. Agricultural experts were involved in assessing these characteristics. The strengths include raising awareness of agricultural managers and specialists about the progress in work performed (the conditional index is 4.13 points) and reducing the consumption of material resources (3.83 points). The introduction of these technologies is encouraged with the availability of the Internet at rural areas (3.56 points). The greatest concern is about the functional and physical depreciation of the material and technical base (3.98 points) and insufficient government support (3.44 points). It is necessary to develop governmental targeted measures on increasing state support for updating the material and technical base of agriculture, restoring the human capital in the industry, and developing technologies for precision farming of domestic (Russian) production, which will reduce the dependence on exchange rate fluctuations.
Russian milk export: problems and development prospects
Authors: Konkina V S , Krasnikov A G , Strokova E A
Published: January 2022

Modern agriculture is showing progressive growth. However, not all segments develop in the same way. The dairy industry is showing conflicting results. A twofold increase in the productivity of cows with a simultaneous decrease in livestock does not allow for expanded production. At the same time, the Ministry of Agriculture of the Russian Federation is consistently implementing an export-oriented model for the development of the domestic agro-industrial complex. The analysis showed that the export of milk and dairy products was stable during 2000-2019. However, in 2020 it was marked by its significant growth. This is due to the influence of many factors that were formulated and analyzed in the article. These factors include: low labor and land costs, success in selection and breeding work, grants and subsidies from the state, large hayfields and pastures, the lack of a system for transferring innovations to production, etc.
Formation of modern ecological culture among students of agricultural universities
Authors: Voronin Boris , Chupina Irina , Voronina Yana , Zhuravleva Lyudmila , Zarubina Elena
Published: January 2022

Modern society differs in production technology from the society of the 20th century. A huge amount of nature’s resources are now being used for human needs. But the use of the resource potential puts a high pressure on nature. Therefore, the question of the development of ecological culture in society is now becoming especially important. A sign of ecological culture is the understanding that the preservation of nature is a prerequisite for the preservation of man. Environmental culture is currently being discussed more actively, since global disasters that threaten humanity are becoming more and more threatening every year. Therefore, the threat of an ecological crisis put a person before a choice - either to stop the impending catastrophe, or to deepen it further and put the world in front of the fact of extinction. That is why it is important to form an ecological culture and, first of all, ecological awareness. The priority areas in each country are now considered to be the formation of an ecological culture not only among adults, but also at the initial stage of school education.
Digital technologies in youth career guidance management for professions of the agricultural and industrial complex of the Sverdlovsk region
Authors: Korotkova E A , Karabut M A
Published: January 2022

The research is aimed at finding ways to effectively integrate traditional career guidance approaches and the capabilities of digital platforms working in the field of youth policy management in the Sverdlovsk region. The ways of intersection of interests of universities and youth policy management bodies in the emerging unified Internet space are outlined. The analysis of digital transformation process in the field of career guidance is carried out. The possibilities of the main federal information platforms in the field of youth work and their effectiveness in terms of indicators are presented: the number of events, the coverage of participants and, what is important for us– the project activities of young people with a career-oriented component. The article provides examples of social projects that already have a digital footprint and a sufficiently large involvement of schoolchildren and students of the Sverdlovsk region. The educational component containing elements of career guidance, which can be further strengthened, is of particular interest. The ways of creating a territorial multilevel digital model of youth career guidance of the Sverdlovsk region are outlined.