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ReS2 is a member of the transition metal dichalcogenide family, which has attracted widespread attention in the field of optoelectronics due to its van der Waals interactions between layers, suitable band gap, high optical absorption coefficient and long carrier migration distance. The excellent characteristics of photoelectric materials and devices are determined by their electronic structure, while the defect energy levels of semiconductors have an important role in regulating the electronic structure. However, research on the defects of bulk ReS2 is still lacking. This paper conducts a study on the formation energy and stability of rhenium vacancy, sulfur va- cancy, tungsten-doped (or tungsten replacing) rhenium, tungsten-doped sulfur, technetium - doped rhenium and technetium-doped sulfur in bulk ReS2 based on first-principles calculations using density functional theory. The results indicate that tungsten doped sulfur and technetium doped sulfur form deep acceptor energy level defects, while rhenium vacancy forms shallow acceptor energy level defect. Under conditions of Re rich and S rich, the defect formation energy of tungsten-doped rhenium is low and can effectively reduce the total energy of the system, improving the stability of the system. Although tungsten - doped sulfur defects can reduce the total energy of the system and improve the stability of ReS2, the large defect formation energy indicates that tungsten doped sulfur defects are difficult to form. These research results help to understand the influence of defect energy levels on the shallow and deep energy levels and stability of semiconductors, and also provide theoretical basis for designing efficient photoelectronic devices based on ReS2 in future experiments. [ABSTRACT FROM AUTHOR]

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Biochar possesses abundant surface functional groups, which can form stable chemical bonds with nitric oxide (NO) molecules through chemical adsorption, making it inexpensive, readily available, and environmentally adaptable with broad application prospects. However, current research on the adsorption characteristics of NO on biochar surfaces mostly remains at the macroscopic mechanism, lacking in-depth analysis of the underlying microscopic mechanism. In this study, based on density functional theory, this paper investigated the adsorption and transformation pathways of nitric oxide (NO) on biochar surfaces, revealing the adsorption property of biochar towards NO. The results show that the energy of the N-down adsorption configuration is generally lower than that of the O-down adsorption configuration, making it a more probable adsorption structure, with oxygen-containing functional groups playing a crucial role in the NO adsorption and the formation of ammonia (NH3). Furthermore, further analysis of the N-down configuration reveals that NO will preferentially replace hydroxyl groups after binding to active sites, ultimately converting to NH3 on the surface of biochar. Additionally, reaction rates were calculated using the canonical variational transition state theory (CVT), indicating that the pathway favored by NO will be limited by reaction rates in different regions. This study employs quantum chemical methods to comprehensively elucidate the microscopic mechanisms of NO adsorption on biochar surfaces, providing theoretical support for optimizing the application of biochar in NO control. [ABSTRACT FROM AUTHOR]

Nanoparticles with unique structures are widely used in polymer materials. In this paper, the co-assembled phase behavior of three-armed star-shaped AB diblock copolymers and homopolymers blending systems was systematically investigated by using a dissipative particle dynamics model. The morphology of AB/A blends co-assembly was effectively controlled by adjusting the concentration ratio of the star-shaped copolymer in aggregate and the length ratio of the AB block. Some interesting structures were predicted, such as the core-shell-patch structure with a thicker shell layer, the disc-like structure with a depressed centre of the shell layer, and the multicompartmental structure with an irregular ellipsoidal shape. It is also found that for star-shaped chains with long A-block, increasing the concentration of A homopolymer in the aggregates can eliminate the nuclei formed by B-block within the aggregates. For star-shaped chains with short A-block, a small amount of A homopolymers can induce the aggregates to co-assemble into multi-compartmental nanoparticles with long striped nuclei. [ABSTRACT FROM AUTHOR]

In this paper, density functional theory was used to study different loading sites of the bimetal Rh@Ru on g-C3N4, and the stable binding configuration was determined. Furthermore, the reaction mechanism of the NH3BH3hydrogen evolution catalyzed by the catalyst was studied. By comparing the activation energies required for the three paths of the NH3BH3 hydrogen evolution reaction, it is found that the activation energy of the rate-limiting step of path III is lower, while the activation energies required for paths I and II are higher, and the reaction path III is easier to carry out, so path III is the optimal hydrogenation path. Three mechanisms of hydrogen evolution of NH3BH3 catalyzed by double noble metal Rh@Ru-supported g-C3N4 are revealed from a microscopic perspective, hoping to provide theoretical information for the optimization and design of the NH3BH3 hydrogen evolution catalyst. [ABSTRACT FROM AUTHOR]

SiGeSn alloy material is a semiconductor material with great application potential in the field of optoelectronics because of its high carrier mobility, long carrier lifetime, and high thermodynamic stability of its structure. In this paper, the electronic structure and optical properties of intrinsic semiconductor Si96 and five groups of doping models Si92Ge2Sn2、Si88Ge4Sn4、Si84Ge6Sn6、Si80Ge8Sn8、Si76Ge10Sn10 are constructed and calculated by using the generalized gradient approximation GGA+U method based on density functional theory. Through the analysis of the calculation results, it can be seen that the addition of Ge and Sn reduces the band gap width of Si materials, and the transformation from indirect band gap to direct band gap occurs. In addition, the SiGeSn alloy with the highest concentration of Ge and Sn has relatively high formation energy, and its stability is worse than that of the material with low Ge and Sn content. With the increase of Ge and Sn doping concentrations, the electronic density of states（DES） shows more and more obvious hybridization, and the peak value of the density of states is mainly provided by the s orbital of Si atoms. The increase of Ge and Sn concentrations also increases the absorption coefficient of SiGeSn alloy in the visible and near-infrared regions, the reflectivity increases in the visible and above wavelength ranges, and the refractive index decreases, which makes the extinction coefficient curve move to the infrared region and the optical properties change, indicating that suitable optical properties can be obtained by adjusting the Ge and Sn concentrations, which provides a research direction for SiGeSn semiconductors in the application of optoelectronic materials and devices in the infrared region. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the electronic structure and optical properties of vacancy defect wurtzite BN are studied based on the first principle calculation. Hence we spoke on the calculated energy band structure and density of states, it turns out that the impurity level appears near the Fermi level due to the lack of B and N in the defect system. Compared with the intrinsic system, with the increase of vacancy concentration, the impurity energy levels become more and the transition energy decreases. The density of states of wurtzite BN with N vacancy defect generally moves to the low energy region, and the energy level is significantly higher than that of wurtzite BN with B vacancy defect. From the analysis of complex dielectric function and optical absorption spectrum, it is found that the absorption of wurtzite BN in the visible region gradually increases with the increase of vacancy concentration. In particular, B22N24 has better absorption effect in the visible region. [ABSTRACT FROM AUTHOR]

Helium exists widely in the implosion process of nuclear fusion and cosmic stars in the warm dense state. Its thermodynamic properties and radiative transport parameters play an important role in the design of fusion experiments and the study of star structure evolution. In this paper, the quantum Langevin molecular dynamics method, which fully considers the physical effects of electron and ion collisions in warm dense matter, is used to simulate the response characteristics of helium ions and electrons in a wide ρ-T region. The state of equation database and electronic thermal conductivity database of warm dense helium in the temperature range of 10-60 kK and density range of 1-24 g/cm³ are constructed, and the radiative opacity of warm and dense helium at this temperature density is calculated. The results of this paper can provide necessary input parameters for fusion physics research and modeling of many basic astrophysical problems. [ABSTRACT FROM AUTHOR]

In this paper, the complexation characteristics of CdTe QDs using butyrylcholine and thiocholine as capping agents were studied with density functional theory (DFT). The stable complexation configurations were first optimized, based on which the relevant adsorption energies, charge densities, UV-Vis absorption spectra and frontier molecular orbital were calculated. It is found that the adsorption energy of butyrylcholine on CdTe QDs is very small, and the electron interaction between butyrylcholine and CdTe QDs is quite weak, which therefore can be attributed to physical adsorption. In the meantime, the absorption intensity of ultraviolet and visible light is weak as well. In contrast, the electron interaction between thiocholine and CdTe QDs is strong, which is chemical adsorption, and the absorption intensity of ultraviolet and visible light is strong. The research results provide theoretical support for the detection of butyrylcholinesterase using CdTe QDs in the experiment. [ABSTRACT FROM AUTHOR]

In this paper, the electronicstructures and magnetic properties of SnO2 doped with non-metallic elements (N) and transition metal elements (Mo, Ru, Rh, Pd) are calculated and analyzed based on the first principles approach. The results show that: the formation energy is closely related to the transition metal atomic radius, with the increase of the transition metal atomic radius, the formation energy is decreasing, where the N-Mo doping system has the lowest formation energy, so the system is the easiest to doping formation. Energy band structure analysis shows that due to the number and distribution of spin up/spin down impurity energy levels of the doping system are asymmetric, the doping systems are magnetic generation. Further exploration of the density of states shows that the magnetic properties of the doped system are due to the p-d orbital hybridisation between the transition metal atoms and the N atoms, the vacancies in the outermost electron orbitals and the single electron coupling. The results show that the SnO2 system is magnetic due to the introduction of doping atoms, and the doped system exhibits subferromagnetic properties, with the best magnetic moment of 1.88 μB for the N-Rh doped system, which is expected to be a good dilute magnetic semiconductor material. [ABSTRACT FROM AUTHOR]

g3 (green gas for gird) environmental protection gas (C4F7N/CO2 mixture), as the most potential new environmentally friendly insulating substitute gas for SF6, has received extensive attention in recent years. Defects such as partial discharge and overheating are detected by analyzing the decomposed components in the g3 gas-insulated combined switchgear, which plays an important role in the evaluation and diagnosis of the operation status of power equipment. In this paper, the modification of Si atoms is proposed to improve the gas sensing and adsorption properties of MoS2. Based on the calculation method of density functional theory (DFT), the intrinsic properties of MoS2 are explored through parameters such as adsorption energy, charge transfer, density of states and local density of states. The adsorption gas-sensing mechanisms of MoS2 and Si-MoS2 to the typical decomposition components of g3 gas—COF2, CF4, CF3CN. The analysis shows that Si atoms have a stable doping structure on the surface of MoS2. Compared with the intrinsic MoS2, the conductivity of MoS2 modified by Si atoms has been effectively enhanced; Si-MoS2 exhibits strong chemical adsorption to COF2 and CF4 gases, it is weak physical adsorption to CF3CN, the adsorption strength is CF4＞COF2＞CF3CN, and in the adsorption process Si-MoS2 always acts as an electron donor, transferring electrons to gas molecules; Si-modified MoS2 has selective adsorption to g3 gas decomposition components. It provides a theoretical basis for the development of MoS2 high-performance gas sensors for detecting CF4 and COF2 gases. The research results are also of great significance in reducing greenhouse gas emissions and improving the operational stability of GIS (Gas Insulated Switchgear). [ABSTRACT FROM AUTHOR]

Based on the fact that block copolymers can self-assemble to form many ordered structures under soft confinement conditions, they are widely used in catalysis, electronic devices, optical sensing and other fields. At present, only the self-assembly morphology of linear triblock copolymers under soft confinement has been analyzed. There is no unified conclusion on the self-assembly behavior of copolymers under soft confinement. Based on this background, this paper focuses on studying the morphology of triblock copolymer particles under soft confinement. A phase diagram is constructed by tuning the volume fractions of the three blocks (fA, fB, and fC). Our simulations predicted various unique self-assembled nanostructures, including lamella + sphere, cylinder, perforated layer, lamella + cylinder, core-shell patch. By changing the selectivity between the block and the solvent, the morphology transition of the copolymer with the chain length ratio of 1:x:1 was predicted. The morphology transition mechanism was verified by calculating the ratio of ＜DEE²＞ to the average length (L), the average bond length of B block chains, and their contact number. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated the controlling of the dipole-dipole (D-D) interaction and detuning amount on the quantum memory assisted (QMA) entropy uncertainty of the two-atom system in Markovian and non-Markovian processes. It is found that the memory effect of the reservoir environment causes the dynamical behaviour of the QMA entropy uncertainty of the two-atom system to show a phenomenon of oscillation, the rising trend of the QMA entropy uncertainty is slowed down, and it can suppress the decoherence effect of the system caused by quantum noise in the non-Markovian process. In addition, the D-D interaction has significant control ability to reduce the QMA entropy uncertainty and it has stronger control ability than the detuning amount. [ABSTRACT FROM AUTHOR]

This paper is based on the X-ray photoelectron spectroscopy (XPS and X-ray absorption spectroscopy (XAS with the synchrotron radiation technology. It aims to test the electronic structures of dilute magnetic semiconductor GaMnN films with different Mn doping concentrations prepared by metal organic chemical vapor deposition technology (MOCVD, to explore the influences of Mn doping concentration on the local environment and electronic states of the magnetic atom Mn, and hence to expose the mechanism for the change of material ferromagnetism. The XPS and XAS data analysis show that Mn2+ and Mn3+ coexist in the film samples, the proportion of Mn2+ in sample D is as high as 70%-80%; the N vacancy increases with the increase of Mn doping concentration and it can reduce the hole concentration, as a result, the exchange interaction between Mn 3d and N 2p orbitals is reduced, which weakens the ferromagnetism of the system. In addition, Mn doping concentration also affects the strength of the p-d coupling hybridization ability of GaMnN films. When the Mn doping concentration is 0.018, the system has a strong p-d coupling hybridization ability. [ABSTRACT FROM AUTHOR]

In this paper, V-shaped and W-shaped hole blocking layer (HBL) structures are designed to re- duce the hole leakage into the n-type region of AlGaN -based deep ultraviolet laser diodes (DUV - LDs). DUV - LDs with reference rectangular, V-shaped and W-shaped hole - blocking layer structures are simulated by Crosslight software. Numerical research on the energy band, n-region hole concentration, radiative recombination rate, electro-optical conversion efficiency, output power, carrier concentration in the active region and other characteristics of the three different structures, are conducted respectively. The results show that DUV - LD with a W-shaped hole blocking layer has higher hole effective barrier height, higher radiative recombination rate, lower hole leakage and better slope efficiency, which can effectively reduce the hole leakage in the n-type region of the deep ultraviolet laser diode, and improve its optical and electrical performance. [ABSTRACT FROM AUTHOR]

In this paper, based on Hill kinetics and Michaelis-Menten equation, we built a theoretical model to study the kinetics of H2 AT120 protein phosphorylation promoting the oncogenic transformation. We found that in H2 AubK119-H2 AT120 D-H2 AT120 P signaling pathway, the vaccinia-related kinase 1(VRK1) regulates the kinetic behavior of H2 AT120 protein phosphorylation. Overexpression or underexpression of VRK will cause abnormalities in the phosphorylation process of H2 AT120, which leads to improper gene expression and oncogenic transformation. By investigating the dynamic stability of the H2 AubK119-H2 AT120 D-H2 AT120 P signaling pathway system, we found that the H2 AubK119, H2 AT120 D, and H2 AT120 P present Hopf bifurcation. It confirms the transition characteristics of the system’s evolutionary dynamics over time. This shows that the phosphorylation of H2 AT120 protein promotes the complexity of cancer occurrence and development. Based on the model in this article, we explained the carcinogenic regulation characteristics of VRK, H2 AT12 ubiquitination and [H2 AT120 D] mutation. The results can be used to further understand the carcinogenic mechanism induced by the H2 AubK119-H2 AT120 D-H2 AT120 P signaling circuit. The theoretical results are consistent with the experiment, revealing a carcinogenic mechanism of epigenetic changes caused by phosphorylation of H2 AT120 protein, which can provide a theoretical basis for the design to prevent cancers induced by histone mutations. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) seriously endanger the ecological environment and human health, so it is of great significance to detect VOCs gases with typical functional groups. In this paper, the sensing properties of VOCs gas C2H2, C2H4, HCOOH, CH3OH, HCHO and CH3COCH3 molecules with typical functional groups on the surface of anatase TiO2(101) were investigated. The results show that when the surface with oxygen vacancy defects adsorbs polar molecules, the larger the dipole moment is, the more stable the adsorption system is; when the surface with oxygen vacancy defects is adsorbed on non-polar molecules, the lower the saturation degree of C atom bonding, the more stable the adsorption system. The analysis shows that the differential charge density and charge layout reflect the influence of the size of the dipole moment and the degree of C atom bond saturation on the ability of gas molecules to gain or lose electrons. For polar molecules, the ability of the O atom in the functional group of the gas molecule to gain electrons is OCH3COCH3＞OHCHO＞OCH3OH＞OHCOOH. For non-polar molecules, the ability of the C atom in the functional group to gain electrons is CC2H2＞CC2H4.The analysis of the density of states diagram reveals that the peak position and size of the adsorption system at the Fermi energy level are also influenced by the dipole moment and the saturation of C atoms, which is essentially due to the different redox ability of different functional groups with the material surface. Therefore, the degree of adsorption stability on the surface of the material is closely related to the dipole moment of polar molecules or the degree of bond saturation of C atoms of non-polar molecules. It is of great significance to explore the adsorption gas sensing of organic gases by studying the dipole moment of the gas and the degree of C bond saturation. [ABSTRACT FROM AUTHOR]

Iridium acetylacetonate is a transition metal organic complex composed of transition metal Ir and acetylcaetonato. It is also an important green phosphorescent material and a component of many iridium luminescent materials. In this paper, firstly, the structures of the Ir(acac)3 and [Ir(acac)3]2 were fully optimized at density function theory (DFT), the Infrared and Raman spectra were discussed. Secondly, excited states property is studied by CIS. The results of calculate shows that the electronic absorption spectrum of Ir(acac)3 and [Ir(acac)3]2 are in UV spectral region, absorption peaks of Ir(acac)3 are 260nm,350nm,414nm, absorption peaks of [Ir(acac)3]2 are 299nm,353nm and 401nm . Compared with their gas condition, the absorption in the CH3CN is blue- shifted. The results show that the spectrum by Kunkely and Arnd Vogler include the complex of characteristic absorption spectrum of Ir(acac)3 and [Ir(acac)3]2 . It proves that Ir(acac)3 is exist at higher concentration. Finally, the proportion of monomeric Ir(acac)3 and oligomers [Ir(acac)3]2 could calculated, discusses the forming reason of oligomers [Ir(acac)3]2 . [ABSTRACT FROM AUTHOR]

In this paper, the molecular geometry of dihydromyricetin was optimized based on density flooding theory (DFT)using B3LYP flooding combined with 6-31G group, based on which the active sites of dihydromyricetin molecules were calculated using water as solvent and the infrared spectra was analyzed. The electrostatic potential results showed that the nucleophilic active site of dihydromyricetin is located near the phenolic hydroxyl atom (H23) ; while the electrophilic active site is located in and near the oxygen atom (O32) . The results of frontline molecular orbital studies indicate that the highest occupied orbitals (HOMO) of dihydromyricetin molecules are located near ketone oxygen (O32)and hydroxyl oxygen (O20), indicating that these sites are susceptible to reaction with electrophilic reagents. And the lowest occupied orbitals (LUMO) are located in the carbon atom (C12, C13, C14) region, indicating that these regions can react with nucleophilic reagents. The results of the simplified Fukui function (f) confirm that the electrophilic activity of the f-value of the oxygen atom reagents. The results of the simplified Fukui function (f) confirm that the electrophilic activity of the f-value of the oxygen atom located in the C-O-C bond is larger than those of the oxygen atom in other sites; while the f+ value of the carbon atom located in C8 is larger, so the nucleophilic activity is stronger in this site. The infrared spectral data of dihydromyricetin obtained by theoretical calculations do not differ much from those obtained experimentally, which indicates that the theoretical calculations may be reliable. Thus, it provides some theoretical reference for the experimental and theoretical studies of the relationship between the structure and properties of dihydromyricetin. [ABSTRACT FROM AUTHOR]

CO, SO2, H2S are typical toxic gases gushing out of coal and surrounding rock or produced during production in mines. In the paper, first principles and density functional theory were used to study the adsorption characteristics of rare earth element Sc-doped ZnO on single gas molecules (CO, SO2, H2S). Through the analysis of the Mulliken, band structure, DOS and DCD of each system, the results show that: Sc-ZnO(001)-Zn position doping system has the best stability, the adsorption energy of Sc-ZnO on individual CO, SO2 and H2S molecules was -0.140 eV, -1.885 eV and -0.093 eV, respectively, of which the adsorption of SO2molecules was chemical adsorption and the rest was physical adsorption. The feasibility of Sc-ZnO as a semiconductor gas sensor to detect three toxic gases was determined, especially for SO2 gas, which provided theoretical guidance for Sc-ZnO as a gas sensing material to detect toxic gas in mines. [ABSTRACT FROM AUTHOR]

Nickel – based superalloy, its high-temperature mechanical properties are directly related to the operational safety and service life of the engine, is one of the key materials for manufacturing advanced acroengine hot – section components. In the paper, the influence of ruthenium (Ru) cluster on the deformation mechanism of Ni/Ni, Al nanowire was studied by using the modified analytical embedded atomic model(MAEAM) and mo- lecular dynamics (MD). The obtained results showed that the clastic modulus and yield strength of alloy nanowires decreased with increasing temperature as the uniaxial tensile strain was used. The deformation of nanowires at the lower temperature was caused by the generation and emission of dislocations, leading to lattice slippage. As the anharmonic effect of lattice thermal vibration was unobvious, the significant blocking effect of Ru cluster on the crystalline glide resulted in a slippage area, the distribution of which was only between the cluster and the Ni/Ni, Al phase interface and was asymmetric. At the higher temperature, the deformation of nanowire resulted from the lattice slippage attributing to dislocation emission. Due to the remarkable anharmonic effect of vibration, Ru cluster could ineffectively impede lattice glide and the slip region was asymmetrically distributed with respect to Ru cluster in the Ni3 Al phase. Finally, the influence of Ru clusters on the deformation of nanowire was further analysed from the perspective of its microstructure and stability. [ABSTRACT FROM AUTHOR]

The regulation of PT symmetry in the PT (Parity-Time) symmetric optical waveguide system is mainly realized by the periodic change of complex refractive index materials. In this paper, we give a configuration of manipulating the PT symmetry for the neutral waveguide with additional periodic modulation in the coupled dual-channel waveguide system. After the system is converted into an equivalent unmodulated system with renormalization parameters by high-frequency approximation, it is found that the PT symmetry of the system can be regulated by introducing an additional single-frequency periodic modulation optical waveguide, and the energy spectrum characteristics of the system with periodic modulation of non-Hermitian three-channel waveguide are discussed, Finally, the dynamic evolution of light in non-Hermitian three-channel optical waveguide is given by analytical and numerical methods. [ABSTRACT FROM AUTHOR]

Co, Ni and As doped pyrite crystals have different physical properties that affect their gold-bearing properties and oxidation behavior. In this paper, CASTEP software based on density functional theory was used to investigate the electronic structures of Co, Ni and As doped gold-bearing pyrites and to analyze their stabilities accordingly. Combining the semiconductor type and energy analysis, the order of stability of gold-bearing pyrites with different crystal defects is Fe32S63AsAu< Fe32S64Au< Fe31S64CoAu< Fe31S64NiAu, i.e. As-substituted gold-bearing pyrite is more susceptible to oxidation during oxidation pretreatment. This study can further explain the oxidation pretreatment pattern of gold-bearing pyrites with crystal defects in micro-dipping gold ores. [ABSTRACT FROM AUTHOR]

In recent years, rare-earth(RE) borate materials have attracted much attention because of their rich structures and excellent optical properties. In this paper, we use a first-principles high-throughput screening tool to obtain five high-performing short-wavelength rare-earth boronate materials and further investigate their electronic structures and optical properties. The results show that the UV cut-off edges and birefringences of these materials are 210 nm, 0.0934@1064 nm (LaB3O6), 246 nm, 0.0880@1064 nm (LaBO3), 347 nm, 0.0815@1064 nm (LuBO3), 272 nm, 0.0914@1064 nm ( ScBO3), 279 nm, 0.0920@1064 nm (Sc3B5O12). In this paper, we analyzed the mechanism of the influence of each atomic and ionic group on the birefringence using the projected density of states, real space atomic real cuts, and Born effective charge, and the results showed that RE-O groups and B-O polyhedra make the main contributions in determining the optical properties. [ABSTRACT FROM AUTHOR]

BACKGROUND: Percutaneous vertebroplasty is the most widely used method for the treatment of osteoporotic vertebral compression fractures, and most studies have concluded that percutaneous vertebroplasty increases the probability of adjacent vertebral secondary compression fractures in patients with osteoporotic vertebral compression fractures. However, controversy remains regarding the risk factors associated with adjacent vertebral re-fracture caused after percutaneous vertebroplasty. OBJECTIVE: To summarize the influencing factors of adjacent vertebral compression fractures after percutaneous vertebroplasty in patients with osteoporotic vertebral compression fractures, in order to provide a certain reference for reducing the risk of its occurrence as well as formulating the corresponding treatment plan. METHODS: Using “osteoporosis, fracture, percutaneous vertebroplasty, adjacent vertebral compression fractures, risk factors” as the Chinese search terms, “osteoporosis, osteoporotic vertebral compression fractures, percutaneous vertebroplasty, adjacent vertebral compression fractures, risk factors” as English search terms, computerized searches were conducted on CNKI, Wanfang Medical Network, VIP, PubMed, Springer, ScienceDirect, and Elsevier databases. The search timeframe focuses on January 2018 through September 2023, with the inclusion of a few classic forward literature. The literature was screened by reading the titles and abstracts, and 83 papers were finally included in the review. RESULTS AND CONCLUSION: (1) Osteoporotic vertebral compression fractures are one of the most common complications of osteoporosis, placing elderly patients at a significant risk of disability and death. Percutaneous vertebroplasty is a practical and effective treatment for osteoporotic vertebral compression fractures. (2) With the popularity of percutaneous vertebroplasty, its secondary vertebral compression fractures have gradually increased, with adjacent vertebral compression fractures being the most common. (3) Previous studies have only discussed the effects of factors such as bone mineral density, multiple vertebral fractures, body mass index, age, sex, amount of bone cement, cement leakage, and anti-osteoporosis treatment on secondary compression fractures of adjacent vertebrae after percutaneous vertebroplasty, and summarized the number of vertebral fractures, timing of the operation, surgical approach, cement material, diffuse distribution of bone cement, recovery height of the injured vertebrae, and wearing of a support after surgery, which is not yet comprehensive. The analysis of the specific mechanisms of risk factor-induced adjacent vertebral fractures is relatively rare. (4) The results of the article showed that low bone mineral density, advanced age, perimenopausal women, multiple vertebral fractures, excessive recovery of the height of the injured vertebrae, cement leakage, comorbid underlying diseases, and poor lifestyle habits were the risk factors for secondary adjacent vertebral compression fractures after percutaneous vertebroplasty, and that maintaining a normal body mass index, early surgery, bilateral percutaneous vertebroplasty, use of a new type of cement material, an appropriate volume of bone cement injection and uniform cement dispersion, regular anti-osteoporosis treatment, and postoperative brace wearing are protective factors for secondary adjacent vertebral compression fractures after percutaneous vertebroplasty. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Bibliometrics and visual analyses based on thematic literature are particularly important for understanding the foundation and frontiers of postmenopausal osteoporosis research. OBJECTIVE: To perform bibliometric, citation, and visualization analyses of highly cited SCI papers in postmenopausal osteoporosis research over the last 20 years. METHODS: The top 100 highly cited papers on postmenopausal osteoporosis published between 2003 and 2022 included in SCI-EXPANDED catalog of the Web of Science database were obtained for bibliometric measure and visual analysis using CiteSpace software. RESULTS AND CONCLUSION: The top 100 highly cited papers have a total of 67 377 citations in the Web of Science Core Collection, with an annual average of 49.17 citations per paper. Postmenopausal osteoporosis research primarily involves medical, engineering, biological, and multidisciplinary fields. The subcategories are dominated by endocrinology and metabolism, and medicine: internal medicine. Stable and close cooperative network relationships have been formed globally. United States, University of California System, Cummings, and Steven R are the country, research institution, and author, respectively, with the most highly-cited publications. The frontiers of postmenopausal osteoporosis research mainly include calcium and vitamin D supplementation and fracture risk, clinical studies of bisphosphonates in the treatment of postmenopausal osteoporosis, atypical femur fracture, clinical studies of new drugs and sequential treatment of postmenopausal osteoporosis, predictors of fracture risk, mid- and long-term follow-up of osteoporotic vertebral compression fractures, genetic polymorphisms and hereditary factors, formulation and updating of clinical practice guidelines for postmenopausal osteoporosis. Large cohort studies, high-quality randomized controlled trials, systematic reviews, meta-analyses, and clinical practice guidelines are the great engines that drive the development of clinical research in postmenopausal osteoporosis. We should make efforts in the above areas to improve China’s international influence in the field of osteoporosis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Currently, there is no drug that can completely cure osteoarthritis and its pathogenesis is still unclear. Circular RNAs (circRNAs) are differentially expressed in patients with osteoarthritis and are closely associated with various pathological processes in osteoarthritis. circRNAs play an important role in various physiological and pathological processes, such as chondrocyte homeostasis, extracellular matrix formation, and inflammatory response. OBJECTIVE: To mainly review the effects of circRNAs on pathological factors related to osteoarthritis, as well as the types and expression levels of circRNAs in osteoarthritis. METHODS: Related articles published from 1976 to August 2023 were retrieved from CNKI, WanFang, VIP, PubMed, Medline, Web of Science and Elsevier databases. The keywords were “osteoarthritis, circular RNA, non-coding RNA, synovial tissue, chondrocytes” in Chinese and English, respectively. All the relevant articles were screened, summarized, analyzed, and finally 69 papers were included in the review. RESULTS AND CONCLUSION: circRNAs are non-coding RNAs widely found in eukaryotic cells, with covalently closed continuous loop structure, but with no 5′ hat structure and 3′poly A tail, which are involved in multi-gene and multi-target regulatory networks and cannot be degraded by nucleic acid exonucleases (RNase R). circRNAs have a high abundance, high conservativeness and stability, and cell and tissue specificity. circRNAs have biological functions such as acting as molecular sponges for miRNAs, regulating linear RNA transcription and RNA shearing, interacting with RNA-bound proteins, and translating proteins. circRNAs regulate chondrocyte apoptosis and proliferation, degradation of cartilage extracellular matrix, and inflammation and other physiopathologic processes. circRNAs are expected to become biomarkers and potential therapeutic targets for clinical diagnosis and prognosis of osteoarthritis, and may become a new strategy for clinical treatment of osteoarthritis in the future. [ABSTRACT FROM AUTHOR]

BACKGROUND: Excessive accumulation of uric acid in the body can lead to diseases such as hyperuricemia and gout, which is a risk factor for cardiovascular and renal dysfunction. Many sports medicine organizations at home and abroad advocate the formulation of exercise prescription to prevent and treat chronic diseases, but this method has not been effectively carried out in the prevention and treatment of hyperuricemia. OBJECTIVE: Based on an overview of the formation of hyperuricemia and the regulation of uric acid by exercise and its related mechanisms, to condense a program suitable for popular exercise to prevent and assist in the treatment of hyperuricemia, and to propose precautions to be taken when exercising for patients with different stages of hyperuricemia. METHODS: PubMed and CNKI were searched for relevant literature published before October 2023 using the keywords of “uric acid, gout, aerobic exercise, strength training, high-intensity interval training, obesity” in English and Chinese, respectively. Initial screening was done by reading the titles and abstracts to exclude repetitive studies and literature with irrelevant content, and finally 64 papers were included for review. RESULTS AND CONCLUSION: The formation of hyperuricemia is caused by excessive synthesis of uric acid by the liver, insufficient excretion by the kidneys, or both. Exercise can improve the uric acid level in the body by regulating the activity of antioxidant enzymes, the expression of uric acid excretion protein and lipid metabolism. Aerobic exercise, strength training, high-intensity intermittent exercise can effectively regulate uric acid levels, reduce inflammation, promote the expression of uric acid excretion protein and lipid metabolism, and achieve good results in the prevention and treatment of hyperuricemia. Currently, there is a lack of research on the mechanisms underlying direct regulation of uric acid levels by exercise, and future studies need to explore in greater depth the possible mechanisms of regulation of uric acid levels by exercise and refine the effects of different exercise modalities on patients with different characteristics of hyperuricemia. [ABSTRACT FROM AUTHOR]

BACKGROUND: The application of orthodontic force triggers autophagy in the periodontal tissue via diverse signaling pathways, augmenting or attenuating the activity of relevant cell types such as periodontal ligament cells, osteocytes, osteoclasts, and osteoblasts, thus facilitating the process of periodontal remodeling. OBJECTIVE: To review the research progress in orthodontic force mediated autophagy in periodontal tissue and its impact on orthodontic tooth movement. METHODS: The PubMed, Web of Science, China Biology Medicine disc and CNKI were searched for literature published from 2010 to 2023 to summarize the progress in orthodontics-related autophagy. And 76 papers were finally included in the analysis and discussion. RESULTS AND CONCLUSION: Orthodontic force can trigger a series of biochemical signal changes through periodontal mechanical receptors and aseptic inflammation they cause, leading to autophagy in periodontal tissue. Subsequently, autophagy generates corresponding feedback through cascaded amplified signaling pathways such as Phosphoinositide 3-kinase/protein kinase B, Hippo, and mitogen-activated protein kinase pathways, promoting periodontal tissue remodeling and ultimately achieving tooth movement and stability. Orthodontic force-induced autophagy can differentially regulate bone resorption on the tooth pressure side and bone formation on the tension side. Related targets have good prospects in the clinical application of orthodontic treatment. Orthodontics and autophagy have complex mechanisms. However, existing research has only focused on exploring the role of autophagy in orthodontic tooth movement. Further exploration is needed to investigate the mutual regulatory effects between autophagy and orthodontic tooth movement, as well as the interactions between upstream mechanical receptors and signaling pathways involved in related pathways. [ABSTRACT FROM AUTHOR]

BACKGROUND: Gait is one of the optimal indicators of functional status in older adults. Gait parameters are associated with adverse health outcomes in older adults. OBJECTIVE: To summarize and compare the practical value of gait parameters, and to review the progress of research on spatio-temporal parameters and the risk of adverse health outcomes in older adults. METHODS: PubMed, Web of Science, and CNKI were searched for relevant literature published from January 2010 to June 2023 using the search terms of “gait speed, walking speed, step length, cadence, step frequency, step time, walking base, aged and elderly” in English and Chinese, respectively. A total of 52 papers were finally included for the systematic review. RESULTS AND CONCLUSION: Currently, researchers have focused on three basic temporal-spatial parameters, namely, step speed, step length and step frequency, to explore their association with adverse health outcomes in older adults. Reduced gait speed in older adults may increase the risk of falls, all-cause mortality, and may be an independent predictor of all-cause mortality. Older adults with slow gait speed are at higher risk of cognitive decline, and may be the preferred gait parameter in assessing cognitive impairment in older adults. Older adults with slow gait speed are more likely to have debilitating or common chronic illnesses, and are at higher risk of hospitalization and public care. Step length is positively correlated with individual height and lower limb length, but age-induced shortening of step length is not related to height or lower limb length, and shortening of step length reflects reduced physical function in older adults, and shortening of step length is a risk factor for falls and cognitive decline in older adults. Stride frequency is often used as a measure of exercise intensity, and a stride frequency of ≥ 100 steps/minute is predictive of all-cause mortality, and slowing of step frequency may lead to a higher risk of falls, hospitalization and all-cause mortality in older adults. Changes in gait parameters are closely related to the level of physical fitness in older adults, and there may be a bidirectional relationship between the two. The results of the study will provide a theoretical basis for further improving risk screening in clinical populations, refining health risk assessment in the elderly, improving health protection and promoting active health in the elderly. [ABSTRACT FROM AUTHOR]

The physical and chemical adsorptions of hydrogen are the basic forms for hydrogen storage, and the dissociation energy barrier of H2molecules is an important factor determining the kinetic performance of reversible hydrogen storage. Nanoclusters are important scale for studying the hydrogen-storage properties of materials. Studying interaction properties between hydrogen and Na-Al clusters can understand the hydrogen-storage properties of Na-Al hydrides at nano scale. In this paper,the adsorption and dissociation properties of H2molecules on the small alloy cluster Na2Al6are studied by density functional theory. The results show that the physical adsorption of H2molecule on Na2Al6cluster is very weak,but it can be dissociated easily. The dissociation energy barrier of hydrogen molecule is very low,and the dissociation can occur at moderate temperature. The nanostructured Na2Al6clusters have good chemical hydrogen-storage properties. [ABSTRACT FROM AUTHOR]

Void is a common defect in the preparation of FeCrNiCoCu high - entropy alloy. Thus, this paper employs molecular dynamic simulation to build FeCrNiCoCu models with void for uniaxial tension simulation, and explores the effect of the voids location, void radius and deformation temperature on the mechanical properties. It is found that the void in the crystal with the Z -axis orientation of [111] and at the grain-boundary(GB) will seriously reduce the yield strain and yield stress, but have little effect on the Young's modulus of the model. With the increase of the void radius at the grain boundary, in the elastic stage, the increase of the void radius increases the area of stress concentration, which is conducive to dislocation nucleation, and the mechanical proper- ties of the model decrease accordingly. In the plastic deformation stage, with the increase of the void radius, the initial dislocations tend to expand to the crystal with the Z axis orientation of [001]. The model maintains good mechanical properties at medium and low temperatures; at high temperature, the mechanical properties decrease significantly. In the high temperature plastic deformation stage, the total length of dislocation in the model is low, and the average flow stress is also low. [ABSTRACT FROM AUTHOR]

Two-dimensional Ag2S is a semiconductor material with an indirect wide band gap.It has received extensive attention due to its unique mechanical properties in and out of plane.In this paper,the electronic and optical properties of two-dimensional Ag2S are studied by first-principles calculations based on density functional theory.The two-dimensional Ag2S has strong directional anisotropy.By replacing S with O at different concentrations,it is found that the band gap value increases first and then decreases with the increase of O concentration.Due to the introduction of O element,the symmetry of the two-dimensional Ag2S structure is reduced,which causes the distribution discretization of energy band,light absorption and light reflection.The light absorption and light reflection peaks at 4.56～5.36 eV in the y direction gradually decrease with the increase of doping concentration,and there is an obvious blue shift. [ABSTRACT FROM AUTHOR]

In hydrogen liquefaction process,precooling cycle is an important link,among which the unit energy consumption of MR is relatively low,so it is particularly important to optimize the performance of MR.In this paper,the experimental system of VLE was built by the method of single-phase liquid phase cycle,and the properties of VLE in the ternary system R290+R600a+N2were studied.The temperature range of 273.15 K～323.15 K was used to study the ternary mixing medium R290+R600a+N2,and 18 groups of experimental data were obtained.At the same time,Peng-Pobinson-Stryjek-Vera （PRSV） equation of state combined with van der Waals（vdW） mixing rule was used to calculate the VLE properties of the ternary system.By comparing the experimental data with the calculated results,the average absolute relative deviation AARDp of the system pressure is 0.85%,and the average absolute deviation AADy1,AADy2and AADy3of the system components R290,R600a and N2are 0.0064,0.0027 and 0.0063,respectively. [ABSTRACT FROM AUTHOR]

BACKGROUND: Scoliosis mainly refers to sequence abnormalities in the coronal, sagittal, and axial positions of the spine, with a Cobb angle of ≥ 10°. The patients may experience symptoms such as unequal shoulder height and back asymmetry. Severe cases may affect the patient’s cardiopulmonary function, thereby affecting their daily life. Conservative treatment can control the progression of scoliosis and avoid later surgery. Scoliosis orthosis is currently a commonly used and effective treatment measure in conservative treatment. OBJECTIVE: To summarize and analyze the current research status, hotspots, and trends of scoliosis orthoses both domestically and internationally, providing reference for related research. METHODS: Using bibliometrics and visual analysis as tools, and using a comparison between China and foreign countries as a method, this paper analyzes the literature on scoliosis orthosis journals in the past decade. Based on bibliometrics, the current status of research on scoliosis orthoses is determined. Citespace software is used to analyze key words and identify the current hotspots and future trends in scoliosis orthosis research. RESULTS AND CONCLUSION: (1) At present, the number of literature on scoliosis orthoses is still on a fluctuating upward trend. China and the United States are the main countries for research, with a literature share of over 40%. However, the average citation rate of foreign language literature by Chinese scholars is relatively low. (2) The basic fields of domestic research are mainly surgery and pediatrics, while orthotics and clinical neurology are mainly studied abroad. Among them, there is also a certain number of documents in domestic Chinese medicine, indicating that China is also engaged in the combination of Chinese and Western treatment of scoliosis. The National Natural Science Foundation of China has the highest proportion in the aspect of Chinese and foreign literature, reflecting the importance of the fund attaches to the research of scoliosis orthosis. (3) The authors with the highest number of publications are Qiu Yong and Negrini Stefano, and the most published institutions are the Spinal Surgery Department of Gulou Hospital affiliated to Nanjing University Medical College and UDICE-French Research University. Domestic and foreign authors and institutions have certain communications about this, but not closely, which requires relevant institutions and scholars to further explore and study. (4) From the research hotspots and future trends, the main treatment type is adolescent idiopathic scoliosis, while the production method of the short-column side bending orthosis is three-dimensinoal printing, and the main treatment index is convex progression. The ultimate purpose of treatment is to improve the quality of life of the patients. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, as the popularity of long-distance fitness running continues to rise, more research progress has been made on related scientific issues. Among them, the landing pattern of long-distance running is an important biomechanical research hotspot at the level of running technique. OBJECTIVE: Using CiteSpace to visualize and analyze the relevant literature, the article sorts through the last decade’s literature on the subject to identify the current state, hot spots, and trends in the footprint as well as to further discuss the main research hotspots of the foot strike pattern from a biomechanical perspective. METHODS: “Foot strike pattern,” “Rearfoot strike,” “non-Rearfoot strike,” “Forefoot strike” and “Midfoot strike” were used as keywords to search the Web of Science Core Collection database. RESULTS AND CONCLUSION: A total of 896 relevant papers were finally included. The number of articles published in a year showed an overall upward trend. The top three countries in terms of the number of publications were the United States, China and the United Kingdom; the top three institutions were Harvard University, Shanghai University of Sports and the University of Massachusetts; and the top three authors were Davis Irene S, Hamill Joseph and Fu Weijie. The keywords “barefoot running, runner, injury, footing pattern, kinesiology” appear more frequently, and the keyword clusters include “energy cost, loading rate, footing pattern, risk factors, gait analysis”, and the relevant research still continues to be hot to this day. After analyzing the above data in detail, we found that the overall research intensity of foot strike pattern has remained stable in recent years, and the hotspot mainly focuses on the biomechanical research of foot strike pattern; the trend of this kind of research focuses on the influence and adaptability of different strike patterns (forefoot strike and rearfoot strike) on long-distance runners (barefoot, shoes, distance, speed, injury risk, running economy and energy consumption, etc.). Therefore, there is no “standardized optimal landing,” but there may be “individualized optimal landings.” It is suggested that researchers should select the optimal landing pattern and running technique strategy according to their own habitual way, movement pattern characteristics, exercise level and task attributes. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Stem cell therapy has become an emerging method of treating pathological scars. miRNAs are involved in scarring mechanisms, and the targeted action of some stem cell sources of miRNA is mediated by exosomes. OBJECTIVE: To review the biological properties of miRNA derived from mesenchymal stem cells and its derivatives, the mechanism of treatment of scarring through anti-inflammation, suppression of excessive tissue reconstruction and antioxidation. METHODS: The first author used a computer in September 2023 to retrieve the relevant literature published from January 2000 to September 2023, searching for “stem cell, exosome, miRNA, keloid” in English, and “stem cells, exosome, keloid” in Chinese, eventually incorporating 74 papers for analysis. RESULTS AND CONCLUSION: (1) miRNAs with high expression of exosomes derived from mesenchymal stem cells increase the proportion of M2-type macrophages by promoting the polarization of macrophages, target the regulation of transforming growth factor β, transforming growth factor β receptors or related signaling pathways, inhibit the expression of pro-inflammatory factors, promote the expression of anti-inflammatory factors and other mechanisms to inhibit inflammation and thus suppress scar lesions. (2) miRNAs with high expression of exosomes derived from mesenchymal stem cells can reduce the secretion of matrix metalloproteinases, regulate the balance between matrix metalloproteinase inhibitors and matrix metalloproteinases, inhibit the proliferation and migration of fibroblasts and myofibroblasts, directly reduce the production of collagen and other mechanisms, and ultimately lead to the normal degradation of extracellular matrix, thereby inhibiting excessive tissue remodeling and cicatricial lesions. (3) miRNAs with high expression of exosomes from mesenchymal stem cells can improve the resistance of scar fibroblasts to oxidative stress by regulating reactive oxygen species and hypoxia-inducing factors, and then regulate the proliferation and apoptosis of scar fibroblasts to inhibit scar lesions. (4) Exosomes derived from mesenchymal stem cells have good prospects for scar treatment. Studies on this aspect can find mirnas that regulate inflammatory cells, inflammatory factors, signaling pathways, matrix metalloproteinases, fibroblasts, reactive oxygen species, hypoxia-inducing factors and other key factors from the three aspects of inflammation, tissue remodeling and oxidative stress. Then, by inducing mesenchymal stem cells with high expression of the above miRNA, exosomes were extracted, and finally verified and clinical trials were carried out. [ABSTRACT FROM AUTHOR]

BACKGROUND: Osteoarthritis is a common chronic inflammation of joints caused by degenerative changes of articular cartilage. More and more studies have shown that mechanical stress is closely related to the development of osteoarthritis. The Hippo pathway is not only involved in the development of tissue cells, but also an effecting factor of mechanical stress, which is involved in the regulation of bone metabolism and cartilage metabolism. OBJECTIVE: Regulation of the Hippo pathway may become one of the new targets for intervention in osteoarthritis. Therefore, this paper reviewed the research on the effect of mechanical stress regulation of the Hippo pathway on osteoarthritis to provide ideas for the pathogenesis of osteoarthritis and provide a new theoretical basis for the treatment of osteoarthritis. METHODS: PubMed, Web of Science, Embase, CNKI, VIP, and WanFang databases were used for a literature search for articles published from inception to 2023 concerning the influence of mechanical stress on osteoarthritis and mechanical stress, Hippo pathway, and osteoarthritis. A total of 75 articles were finally reviewed. RESULTS AND CONCLUSION: (1) Different mechanical stresses may play different roles in cell proliferation, apoptosis and differentiation, osteoarthritis inflammation, and vascular homeostasis in osteoarthritis. (2) Hard extracellular matrix, low cell density, medium shear force, medium tensile force, and compression force can achieve cell proliferation, osteogenic differentiation, and vascular homeostasis, and inhibit inflammatory response by activating YAP/TAZ. (3) Soft extracellular matrix, high cell density, excessive shear force, excessive tensile force, and compressive force inhibit cell proliferation, enhance cartilage differentiation, disrupt vascular homeostasis, and promote inflammation through inactivation of YAP/TAZ, thus promoting the process of osteoarthritis. [ABSTRACT FROM AUTHOR]

BACKGROUND: With the continuous improvement and progress of artificial intelligence technology in the treatment of spinal deformity, a large number of studies have been invested in this field, but the main research status, hot spots and development trends are still unclear. OBJECTIVE: To visually analyze the literature related to artificial intelligence in the field of spinal deformities by using bibliometrics, identify the research hotspots and shortcomings in this field, and provide references for future research. METHODS: The core database of Web of Science was used to search the articles related to artificial intelligence in the field of spinal deformities published from inception to 2023. The data were visually analyzed by Citespace 5.6.R5 and VOSviewer 1.6.19. RESULTS AND CONCLUSION: (1) A total of 165 papers were included, and the number of papers published in this field showed a fluctuating upward trend. The author with the largest number of articles is Lafage V, and the country with the largest number of articles is China. (2) Keyword analysis results show that adolescent scoliosis, deep learning, classification, precision and robot are the main keywords. (3) The in-depth analysis results of co-cited and highly cited articles show that artificial intelligence has three hotspots in the field of spinal deformities, including the use of U-shaped architecture (a mature mode of deep learning convolutional neural networks) to automatically measure imaging parameters (Cobb angle and accurate segmentation of paraspinal muscles), multiview correlation network architecture (i.e., spine curvature assessment framework), and robot-guided spinal surgery. (4) In the field of artificial intelligence treatment of spinal malformations, the mechanism research such as genomics is very weak. In the future, unsupervised hierarchical clustering and other machine learning techniques can be used to study the basic mechanism of susceptibility genes in the field of spinal deformities by genome-wide association analysis and other genomics research methods. [ABSTRACT FROM AUTHOR]

BACKGROUND: The pathogenesis of osteoporosis is complex, and its essence is the weakening of bone formation and the enhancement of bone absorption caused by various reasons, resulting in the imbalance of bone metabolism. In recent years, N6-methyladenosine has been found (N6-methyladenosine, m6A) methylation can prevent and treat osteoporosis by regulating bone metabolism. OBJECTIVE: Taking the regulation of bone metabolism by m6A methylation as an entry point, to systematically sort out and summarize the research progress of m6A methylation in osteoporosis, so as to provide certain theoretical reference bases for the search of new therapeutic targets for osteoporosis. METHODS: CNKI, WanFang, VIP, PubMed, MEDLINE, Nature, and Cochrane databases were retrieved for relevant literature published from database inception to 2023. The keywords were “osteoporosis, m6A methylation, bone metabolism, bone marrow mesenchymal stem cells, osteoblasts, osteoclasts” in Chinese and English. Duplicates and obsolete non-referenced documents were excluded, and a total of 73 standard papers were included for further review. RESULTS AND CONCLUSION: m6A methylation can affect the activity and differentiation of bone marrow mesenchymal stem cells, osteoblasts, and osteoclasts through various pathways to regulate bone metabolism and prevent osteoporosis. The regulatory process of m6A methylation is extremely complex, and its related proteins play different roles in different cells. Even in the same kind of cells, the same type of proteins may have radically different roles, regulating different physiological and pathological processes. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The effect of post-activation potentiation on sports performance is characterized by increased muscle mobility and increased rate of muscle force generation. In this paper, Meta-analysis is used to quantitatively evaluate the effects of post-activation potentiation on sprint speed, jumping performance, and kinetic parameters (peak impulse, peak power, maximum ground reaction force, rate of force generation, etc.) after activation of relative strength levels in the lower limbs. METHODS: Electronic databases such as CNKI, WanFang, Web of Science, PubMed, and Medline were retrieved for randomized control, random crossover, or clear grouping according to the relative strength levels of the lower limbs (non-randomized controls) on the post-activation potentiation effect after activation induced by the relative strength level of the lower limbs. Free weight equipment and rapid telescopic compound exercises were used as main intervention methods in each group. The publication time of the literature was from the inception of each database until August 5, 2023. Endnote software was used to manage the literature. Literature quality assessment was conducted using the PEDro scale for randomized controlled trials and ROBINS-I 2.0 standards for nonrandomized controlled trials. Revman5.4 and Stata15.0 software were used to conduct publication bias evaluation, subgroup analysis and sensitivity analysis of the extracted data, and forest plots were produced for Meta-analysis. RESULTS: Eleven documents (seven randomized controlled trials and four non-randomized controlled trials) were finally included, including 216 subjects. Overall, the methodological quality of the literature was high. According to the grouping standard of 1-repetition maximum/body mass > 2 for the strong group and 1-repetition maximum/body mass ≤ 2 for the normal group, there were 99 subjects in the strong group and 117 subjects in the normal group, all of whom were male. The positive effect of post-activation potentiation on sprint performance in the strong group was significantly higher than that in the normal group [standardized mean difference (SMD)=-1.34, 95% confidence interval (CI): -1.74 to -0.93, P < 0.000 01]; the positive effect of post-activation potentiation on vertical jump height showed no significant difference between the strong and normal group (SMD=0.30, 95% CI: -0.07 to 0.66, P=0.11); the positive effect of post-activation potentiation showed no significant difference between the strong and normal groups in terms of peak impulse (SMD=-0.07, 95% CI:-0.62 to 0.47, P=0.61], peak power (SMD=0.21, 95% CI:-0.29 to 0.72, P=0.12), maximum ground reaction force (SMD=0.31, 95% CI: -0.20 to 0.81, P=0.16) and force generation rate (SMD=0.36, 95% CI: -0.11 to 0.82, P=0.39). CONCLUSION: The post-activation potentiation effect in the strong group can significantly increase the short-distance sprint speed. The potentiation effect after activation of the relative strength level of the lower limbs has similar effects on the kinematic and kinetic parameters, including explosive vertical jump height, peak impulse, peak power, maximum ground reaction force and force generation rate. [ABSTRACT FROM AUTHOR]

Graphene films,as a two-dimensional material,are excellent lubricants for improving the tribomechanical properties of micro/nano electro-mechanical systems ( MEMS/NEMS) . In order to investigate the influence of substrate material and graphene layer number on its friction reduction performance,this paper investigates the influence of graphene layer number on the friction reduction effect by preparing graphene coatings with different layer numbers on different substrates and using a combination of atomic force microscopy ( AFM) experiments and molecular dynamics ( MD) simulations. And by establishing the analytical model of the friction performance of graphene coatings with different layer numbers,it was investigated that the interlayer slip of graphene is the main factor to produce the wear reduction. The results show that the graphene coating has excellent wear reduction effect on both silicon substrate and copper substrate under different loads,and the friction decreases gradually with the increase of the number of graphene layers,and reaches the optimal 99. 3% wear reduction effect when the number of graphene layers is more than 10. The simulation analysis reveals that as the number of layers increases,the dry friction between graphene and substrate transforms into interlayer friction of graphene and generates interlayer shear slip,and the interlayer slip of graphene is the main factor leading to the excellent wear reduction performance of multilayer graphene. [ABSTRACT FROM AUTHOR]

Thedimension,structure and surface chemistry of nanochannels have great impact on the distribution structure and transport properties of the confined solutions. In this paper,a graphene prismatic nanochannel is proposed and investigated. This idealized channel is similar to the nanoporous structure of metal-organic framework material ( MOF), which has been widely studied recently,and has a completely different internal structure from the conventional carbon nanotubes. In this paper,the properties of KCl solution inside graphene prismatic nanochannel with different sizes are studied by molecular dynamics simulation,and then are compared with single-walled carbon nanotubes with the similar size. The results show that there are several high density areas inside the small channel ( ＜ 20 Å ),which is a tendency of crystallization. The results of this study will promote the structural design of MOF and the desire to achieve the nanochannel with high selectivity and high transport rate similar to biological ion channels. [ABSTRACT FROM AUTHOR]

Pyrrole molecules are important organic semiconductor materials,they are suitable for many fields such as microelectronics and optoelectronics,and have successfully led a new technological revolution. The paper is based on density functional theory,the B3LYP/6-311 + + g (d,p) method is used to study the change laws of the physical properties of pyrrole molecules under the action of electric field strength of 0-0. 03 a. u.. It is found that with the increase of the electric field,the molecule is gradually compressed along the x-axis direction,the dipole moment of the molecule decreases,and the total energy decreases. The highest occupied molecular orbitals energy of the molecule remains unchanged,the lowest unoccupied molecular orbital energy is continuously decreased. As a result,the energy band gap of the molecule is continuously reduced,and the stability of the energy band gap cannot be guaranteed,thereby the service life of the semiconductor material is reduced.Through the time dependent density functional calculation,it can be concluded that under different electric fields two ultraviolet absorption peaks appear in pyrrole molecules,in which the π-π* transition of the two C = C double bonds accounts for the main contribution. But with the increase of the electric field strength,its proportion in the transition becomes smaller and smaller. It is investigated that under the electric field of 0. 02 a. u.,the ultraviolet absorption peaks are mainly determined by the 6th,11th,13th and 15th excited states. These provide a good theoretical basis for better research and design of semiconductor materials. [ABSTRACT FROM AUTHOR]

Two-dimensional semiconductor materials with natural bandgap are expected to make up for the zero bandgap defect of graphene and break the bottleneck of its application in fields such as field effect transistors,switching devices,logic circuits. Compared with layered semiconductor materials,non-layered semiconductor materials are usually bound by strong ionic/covalent bonds and are isotropic,so it is a challenge to obtain their two-dimensional structures. In this paper,two-dimensional anisotropic growth of nonlayered CdSe on mica substrate was achieved by chemical vapor deposition. The microstructure,crystalline structure and optical properties of two-dimensional CdSe were characterized in detail. The results show that the sample has a significant photoluminescence ( PL) effect,indicating that the thickness thinning to nanometer level does not destroy the direct bandgap property of CdSe. In addition,with the decrease of thickness,PL peaks of the sample are gradually blue-shifted. In order to further explain this phenomenon,the energy band structures of CdSe with different thickness were studied using the first-principles caculation based on density functional theory. The results show that they all have direct bandgap,and the bandgap increases with the decreasing thickness,which is consistent with the experimental phenomenon. Therefore,the effective control of the bandgap can be achieved by adjusting the thickness of two-dimensional CdSe through the growth parameters,which has guiding significance for the performance improvement of related optoelectronic devices. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on diffusion kinetics and cell signal transduction kinetics,we studied the cell cycle arrest characteristics of small drug molecules. The theoretical model takes into account the dynamic characteristics of the transport of small drug molecules across the cell membrane and the blocking effect of drug molecules entering the cell on the cell cycle. We found that the drug molecules crossing the inner layer of the cell membrane and entering the cells will largely determine the blocking effect of drug molecules on related targeted genes and proteins.The transport characteristics of cell membrane to drug molecules are the key factors that affect drug molecules to block cell cycle. In addition,the degree of degradation of drug molecules will change the interaction time between drug molecules and targeted genes and proteins,thereby changing the inhibitory effect on the growth and proliferation of related cells. By the sensitivity analysis of the parameters in the model,we confirmed the inhibitory effect of many factors in the process of drug molecules passing through the cell membrane and entering the cell on the cell cycle. The theoretical results in this paper are consistent with the simulation and experimental observation,which further reveals the physical mechanism of drug small molecules blocking cell cycle,and can provide necessary references and new solutions for designing precise therapeutic drugs. [ABSTRACT FROM AUTHOR]

In this paper, by means of density functional theory (DFT), the dehydrogenation of NH3BH3 catalyzed by the Ga-N co-doped cobalt phosphide (CoP) catalyzer were calculated and studied.Herein, four possible reaction paths were designed and the energies of the transition states in each path were calculated which can come to a conclusion that pathⅡis the optimal reaction path through the research results, providing a certain theoretical basis for the co-doped CoP catalytic dehydrogenation of NH3BH3. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Ischemic stroke is a highly prevalent disease associated with apoptosis. Neuronal death occurs after cerebral ischemia, including necrosis and apoptosis. The ischemic core region is dominated by necrosis, while delayed neuronal death in the penumbra is dominated by apoptosis. The penumbra has become a target for the treatment of ischemic stroke. This bibliometric analysis was used to identify the characteristics, hotspots, and frontiers of global scientific output related to apoptosis in ischemic stroke over the past 5 years. OBJECTIVE: To analyze the role of apoptosis and its mechanisms in the pathological process of ischemic stroke through a bibliometric approach. METHODS: A total of 927 relevant literature records from 2018 to 2022 were retrieved from Science Citation Index Expanded (SCI-Expanded) and Social Science Citation Index Expanded (SSCI-Expanded) of the Web of Science Core Collection. Research trends and hotspots of apoptosis in ischemic stroke were visualized using Citespace, VOSviewer and Bibliometrix. RESULTS AND CONCLUSION: From 2018 to 2020, the number of papers on the role of apoptosis in ischemic stroke showed an upward trend, but in 2020, the number of papers began to reduce. China had the largest number of publications, and the United States ranked the second. Capital Medical University and BRAIN RESEARCH BULLETIN were the institutions and journals with the most articles, respectively. In recent years, the two keywords “expression” and “oxidative stress” have appeared more frequently. The bibliometric study showed that in the past 5 years, most of the studies focused on basic research, in which research on the role of apoptosis in ischemic stroke has gradually decreased in the last 3 years, showing a downward trend. On the contrary, nerve regeneration has gradually become a research hotspot, especially the regulation of neurotrophic factors under the influence of different mechanisms, and the research on angiogenesis and glial cell repair is on the rise. At the same time, apoptosis in nerve regeneration is a potential point of discovery. [ABSTRACT FROM AUTHOR]

BACKGROUND: Heart rate variability biofeedback is a respiratory training method that uses slow and deep breathing at the resonant frequency to induce rhythmic, high-amplitude oscillations in the cardiovascular system, thereby stimulating and exercising the autonomic and baroreflex. However, current studies have not systematically reviewed how heart rate variability biofeedback modulates the autonomic function and produces effects. There is a lack of public understanding of the mechanism of heart rate variability biofeedback, and its application progress and scheme are not fully understood. OBJECTIVE: To review the existing experimental studies on the effects of heart rate variability biofeedback on symptoms in different populations at home and abroad and to introduce the mechanisms and advances in the application of heart rate variability biofeedback to modulate the autonomic nervous system. METHODS: “Heart rate variability biofeedback, resonance breathing, heart rate variability, autonomic nerve, breathing training, chronic diseases, mental illness, biofeedback” were used as Chinese or English keywords to search in CNKI, WanFang Database, PubMed, and Web of Science. A total of 72 core related papers were included according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION: The body’s oscillation system and resonance system are essential for the effectiveness of heart rate variability biofeedback. Oscillations reflect the response to external stimuli and self-regulating reflex systems, while resonances involve synchronous oscillations that result in higher amplitude operations. The balance between sympathetic and parasympathetic nerves is crucial for maintaining a stable internal environment. Autonomic nervous system disorders are associated with reduced heart rate variability and are closely linked to the progression of related diseases. Heart rate variability biofeedback utilizes the resonance characteristics of the cardiovascular system, inducing rhythmic high-amplitude oscillations by employing deep slow breathing at the resonance frequency. This method improves the regulatory function of the sympathetic and parasympathetic system reflexes and enhances the balance regulation between the two systems. Two major mechanisms of cardiovascular system resonance are the baroreflex closed-loop pathway and respiratory sinus arrhythmia. These mechanisms, along with the unique delay of baroreflex, result in a 0° phase angle oscillation between heart rate and respiration and a 180° phase angle oscillation between blood pressure and respiration during breathing at the resonant frequency rhythm. Periodically stimulating the human cardiovascular oscillation system through this method is an easy-to-operate and effective training approach. Currently, heart rate variability biofeedback is mainly applied in the fields of mental illness, chronic disease, and sports. However, the intervention mechanism and efficacy are unclear, the intervention content, frequency and duration are varied, and there are limited review studies on the intervention methods tailored to different types of individuals. As a non-drug and non-invasive intervention, heart rate variability biofeedback can significantly increase heart rate variability, regulate the balance between sympathetic and parasympathetic nerves, and improve the stability and adaptability of the autonomic nervous system. In the future, it is suggested to investigate the mechanisms and potential applications of the pathways of the heart rate variability biofeedback that induce cardiovascular resonance. It is also recommended to incorporate long-term follow-ups to assess the sustained value of heart rate variability biofeedback in various fields. This would provide new directions and strategies for the comprehensive treatment of complex diseases. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

(1) Background——China is the world’s largest consumer and largest exporter of wood-based panels. As the largest consumer of wood-based panels, does China’s super-large domestic market promote export trade? How to rely on the super-large domestic market to promote export trade? The home market effect test can answer whether the domestic market has a promoting effect on export trade, and the home market effect theory can also explain the reasons of the home market effect and explore the paths for China’s wood-based panels to play the advantage of the super-large domestic market and promote export trade. (2) Methods——Taking the home market effect as the theoretical perspective, this paper constructed the home market effect model of China’s wood-based panels export trade based on the trade gravity model. The research data mainly came from FAOSTAT database, UN Comtrade database, WDI database, CEPII database and EIA website. Based on the panel data of China and 48 export trading partners from 1995 to 2020, this paper analyzed whether there were home market effect, period differences and market differences in China’s wood-based panels export trade, and discussed the influence of traditional factor endowments. (3) Results——During the period from 1995 to 2020, there were both home market effects caused by relative demand scale and home market effects caused by relative demand level in China’s wood-based panels. The scale economy effect was the root cause of the home market effect of China’s wood-based panels, the agglomeration economy effect played an important role, and the improvement of product quality and technological innovation effectively promoted the home market effect. The driving force of China’s wood-based panel exports was constantly evolving. The domestic market was the basic driving force, it showed the transformation from the domestic demand scale to the domestic demand level, and had the characteristics of export orientation, and was significantly affected by the scale and level of demand in the trade market. In trade markets with different income levels, there were differences in home market effect. The product quality played a key role, and improving the product quality was conducive to exerting the home market effect caused by the relative demand level. In terms of traditional factor endowments, China’s wood-based panels export was greatly affected by labor endowments and negatively affected by capital endowments, but it was less affected by forest resources endowments. However, with the aging of population and the rise of labor costs in China, the low-cost advantage based on labor endowments was constantly being lost, and China’s wood-based panels need to gradually transform and upgrade from the low-price competition model of quantity expansion to the high quality development model of high added value and high product quality. (4) Conclusions and Discussions——In order to give full play to the home market effect, cope with the changes in the international market and realize the mutual promotion of the domestic and international double cycles, the following policy recommendations are put forward: First, stick to the strategy of expanding domestic demand, build a strong domestic market from the scale and level of demand, and strengthen the advantages of the super-large domestic market. Second, accelerate supply-side reform, continue to eliminate backward production capacity, increase the scale of single-line production, encourage mergers and restructuring, focus on supporting large enterprises, and give full play to the effects of economies of scale. Third, actively carry out the construction of industrial parks, encourage various forms of collaboration, share resources, knowledge, technology and management experience, and give play to the industrial agglomeration effect. Fourth, continue to improve product quality and implement branding strategy. Fifth, continue to strengthen technological innovation, and vigorously popularize and apply advanced equipment and technology. Sixth, attract and promote more capital to enter the industry and promote industrial transformation and upgrading. [ABSTRACT FROM AUTHOR]

(1)Background——The evaluation of human capital can provide a scientific basis for improving the level of human capital in the state-owned forest farms, ensure the smooth transformation of the workers’ livelihood, and minimize the impact of the implementation of the policy on the life of the workers’ families. (2) Methods——The research data came from the monitoring survey of people’s livelihood in the key state-owned forest areas in Northeast China carried out by the College of Economics and Management of Northeast Forestry University, and the valid sample number was 243 households. This paper firstly established the evaluation indicators system of human capital of the state-owned forest farms in Northeast China by using fuzzy matter-element method, then analyzed the past human capital status and existing problems of the state-owned forest farms in Northeast China through these standardized and systematic quantitative indicators, and finally put forward some relevant policy suggestions. (3) Results——Although the comprehensive evaluation level of human capital of Suiling and Youhao Forestry Bureau Co., Ltd. did not change from 2019 to 2020,there were some differences in the specific values of evaluation indicators. In 2020,the specific evaluation indicator value of Suiling Forestry Bureau Co., Ltd. increased by 0.0682,while the specific evaluation indicator value of Youhao Forestry Bureau Co., Ltd. decreased by 0.0034.The occurrence of data fluctuation was more likely to be caused by the randomness of sample household selection. The comprehensive evaluation level of human capital of Qinghe and Wumahe Forestry Bureau Co., Ltd. changed. The comprehensive evaluation level of human capital of Qinghe Forestry Bureau Co., Ltd. changed from good to excellent, and the comprehensive evaluation level of human capital of Wumahe Forestry Bureau Co., Ltd. changed from medium to poor. This was largely the result of disastrous household health expenditures and vocational skills training. Therefore, improving the level of human capital should focus more on the health and education of the workers. (4) Conclusions and Discussions——Human capital is one of the most important input factors of economic production, which directly participates in the process of economic production. Generally speaking, a higher level of education can enhance the ability of workers to innovate and start businesses, optimize the structure of the labor forces, improve the quality of human capital, improve labor productivity, create economic value, and then meet the needs of social development. Human capital has economic value, and the production capacity contained in it shows a trend of multiplication and expansion. Human capital can greatly affect the research and development and application of technology, improve the productivity of labor and material capital, promote the quality change, efficiency change and power change of economic development, and increase production income. Therefore, it is very important to solve the problems of the formation, development and accumulation of human capital to realize the sustainable livelihood of the workers of the state-owned forest areas in Northeast China. So the government should improve the existing relevant systems conducive to the accumulation of human capital, such as education, health care, social security and other systems, on the basis of making full use of the stock of human capital, accelerate the accumulation of human capital increment, and at the same time improve the quality of human capital. On the stock of human capital, we should control the loss of human capital in forestry. On the increment of human capital, we should perfect the introduction mechanism of talents in order to attract talents better. On the quality of human capital, we should take the three-dimensional vocational training network as the main force to strengthen the skills training of the workers. [ABSTRACT FROM AUTHOR]

(1)Background——Nowadays, the problem of global warming is becoming increasingly serious, and energy conservation and emission reduction are imperative. Forestry is an important basic industry of national economy, and forestry enterprises play an important role in promoting economic and social development and protecting ecological environment. Carbon accounting information disclosure can meet the needs of stakeholders for information acquisition, enhance the trust of investors in enterprises, improve the market valuation of enterprises, and promote the sustainable development of enterprises. At present, there are relatively few studies on the correlation between the quality of carbon accounting information disclosure and forestry enterprises value. (2) Methods——On the basis of theoretical analysis, this paper put forward the research hypotheses. The enterprises value was selected as the dependent variable, the quality of carbon accounting information disclosure was selected as the independent variable. Based on the unbalanced panel data of 80 listed forestry companies in China from 2013 to 2022,this paper discussed the relationship between the quality of carbon accounting information disclosure and the value of the listed forestry companies through empirical analysis, and identified the influencing factors of the quality of carbon accounting information disclosure. (3) Results——First, according to the descriptive statistical analysis, the quality of carbon accounting information disclosure of the listed forestry companies in China is different, and there is still a lack of disclosure awareness. Second, according to the correlation analysis, the correlation coefficients between the two variables are less than 0. 8,indicating that there is no serious multicollinearity. Third, according to the multiple linear regression analysis, the quality of carbon accounting information disclosure has a significant positive impact on the value of the forestry enterprises, and the enterprise scale has a significant positive relationship with the quality of carbon accounting information disclosure. Compared with the non-state-owned forestry enterprises, the quality of carbon accounting information disclosure of the state-owned forestry enterprises is higher. Fourth, according to the robustness test, the above empirical results have been further confirmed. (4) Conclusions and Discussions——Based on the above analysis, the following conclusions can be drawn: First, the quality of carbon accounting information disclosed by the listed forestry companies is quite different, and the overall quality is not high. Second. The higher the quality of carbon accounting information disclosed by the listed forestry companies, the higher the enterprise value will be. Third, there is also a significant positive correlation between the quality of carbon accounting information disclosure of the listed forestry companies and the enterprises scale and the nature of the actual controllers. Based on the above conclusions, the following policy suggestions are put forward: First, forestry enterprise managers should attach great importance to the disclosure of carbon accounting information, and strive to improve the quality of carbon accounting information disclosure from five aspects: carbon emission disclosure, carbon emission reduction performance, carbon information disclosure carriers, carbon emission reduction management, carbon emission supervision and certification disclosure, so as to continuously improve the enterprise value. Second, the government departments and regulatory agencies should further improve laws and regulations related to carbon accounting information disclosure, formulate disclosure standards suitable for China’s national conditions, and continuously strengthen supervision and punishment of forestry enterprises, so as to help the forestry enterprises achieve sustainable development. [ABSTRACT FROM AUTHOR]

(1) Background——Driven by the “double carbon” policy, forestry development has ushered in new opportunities. The pledge financing of the expected revenue rights of forestry carbon sinks broadens the financing paths of forest operators. It is of great significance to transform the ecological value of forestry carbon sinks into economic value for the sustainable development of forestry and the realization of carbon neutrality. (2) Methods——Taking the forest quality and pledge rate of financial institutions as the key variables, this paper established the management decision model of forest operators and financial institutions under the expected revenue rights pledge financing, and combined with the relevant data of the actual cases, the numerical simulation method and Matlab software were used to analyze the optimal strategies of both sides of the loan. (3) Results——In terms of forest quality, the fluctuation risk of forestry carbon sinks output and the increase of forest scale are not conducive to the improvement of forest quality, while the increase of carbon sinks market price and financing subsidies are conducive to the improvement of forest quality. In terms of the pledge rate of financial institutions, the increase of the fluctuation risk of forestry carbon sinks output and the increase of forest area under large forest scale will inhibit the improvement of the pledge rate, thus aggravating the financing difficulties of forest operators, while the increase of carbon sinks market price, financing subsidies and the forest area under small forest scale will promote the improvement of the pledge rate. In terms of forestry profits, the increase of fluctuation risk of forestry carbon sinks output will reduce forestry profits, while the increase of carbon sinks price, financing subsidies and forest scale will help increase the revenue of forest operators. In terms of the effectiveness of the expected revenue rights of forestry carbon sinks on the improvement of forest quality, compared with sufficient funds, when the fluctuation risk of output is moderate, the forest scale is moderate and the price of carbon sinks is low, pledge financing is more conducive to improving the management enthusiasm of forest operators, and thus improve forest quality. When the fluctuation risk of output is too high or too low, the forest scale is too large or too small, and the carbon sinks market price is high, the forest operators with sufficient funds have a higher willingness to improve the forest quality. (4) Conclusions and Discussions——When implementing the pledge financing of forestry carbon sinks revenue rights, the following policy suggestions are put forward in order to achieve high-quality development of forests and alleviate the financing difficulties of forest operators: First, strengthen the monitoring of forestry carbon sinks projects. The operation status of carbon sinks forests should be monitored regularly in order to detect the hidden risks in time, so as to reduce the uncertain risks of the output of carbon sinks. Second, establish a control mechanism of carbon sinks price. On one hand, starting from the demand side of carbon sinks, the price of carbon sinks should be increased through multiple channels, such as encouraging large and medium-sized activities such as conferences, forums and performances to prioritize the purchase of forestry carbon sinks to offset carbon emissions and achieve carbon neutrality. On the other hand, we should be alert to the high price of carbon sinks leading to high emission reduction costs for the main bodies of social economy. Third, the government should introduce a special loan subsidy policy for the pledge financing of forestry carbon sinks. Fourth, the government should guide the forest operators to carry out forest management by providing technical support and training so as to accurately increase the carbon sinks under the moderate scale of operation. [ABSTRACT FROM AUTHOR]

(1) Background——With the acceleration of urbanization and the in-depth implementation of sustainable development, China’s urban landscaping construction has reached an unprecedented level in scale and speed. While the area of urban landscaping continues to expand and the quality continues to improve, the amount of landscaping waste such as pruning, fallen leaves and grass clippings generated in maintenance and management is also increasing. Scientific and effective disposal and utilization of urban landscaping waste and promotion of landscaping waste recycling are of great practical significance for further promoting the comprehensive and effective implementation of garbage classification and the ecological, green and low-carbon development of the cities. (2) Methods——Based on the analysis of the externality of landscaping waste, this paper discusses the ways to reuse landscaping waste using PPP application mode, in order to reduce its negative externality and correct its positive externality. According to the operation cycle, the urban landscaping waste recycling is divided into the early, middle and late stages of the PPP mode. In the process of applying the PPP mode to the disposal of urban landscaping waste, it needs to be gradually integrated into every link of landscaping waste disposal, and finally form an industrial system of urban landscaping waste disposal dominated by the PPP mode and operated by the market mechanism. (3) Results——There are negative externalities in traditional urban landscaping waste disposal. The original negative externalities are modified to positive externalities by changing the disposal methods of urban landscaping waste. The modified method of urban landscaping waste disposal is carried out through PPP mode, and is analyzed and promoted through three stages of the pre-implementation, mid-implementation and post-implementation stages. In this paper, the application of PPP mode to the disposal process of urban landscaping waste is divided into three stages, and the specific operation mode of each stage is designed: In the early stage, it is the construction-introduction-management mode, in which the government is dominant and the role played by enterprises has certain limitations. In the middle stage, it is the transition-cooperation-expansion mode, in which the market gradually improves and capital gradually flows in, enterprises play an increasingly large role, and the dominant position of the government gradually weakens. In the later stage, it is an all-round cooperation-large-scale operation-industrialization development mode, in which the market mechanism is basically perfect, enterprises occupy the dominant position, and the government gradually fades out of the market. Finally, it gradually establishes an industrial system of the urban landscaping waste recycling dominated by the PPP mode, with perfect market-oriented operation mechanism and sound industrial chain. (4) Conclusions and Discussions——The PPP operation mode can not only solve the externalities brought by urban landscaping waste disposal, but also bring economic, social and ecological effects. In order to improve the recycling efficiency of urban landscaping waste and establish a green and low-carbon production mode, this paper puts forward the following policy suggestions: First, stimulate the enthusiasm of the government and enterprises in promoting the deep integration of the PPP mode and the urban landscaping waste recycling industry. Second, improve the contract terms and relevant laws and regulations for the PPP projects of the urban landscaping waste recycling. Third, increase public participation in PPP projects for the urban landscaping waste recycling. [ABSTRACT FROM AUTHOR]

(1)Background——Since the Healthy China Strategy was put forward, the big health industry has developed rapidly, including the forest health care tourism industry. Fully understanding the tourism demands of tourists for forest health care, determining the core elements of forest health care tourism development in forest parks, and effectively meeting the tourism demands of tourists are of great significance for improving forest tourism service quality and promoting the development of forest health care tourism industry. (2) Methods——Based on the attractive quality theory, this paper firstly constructed the demand element system of forest health care tourism, which consisted of 23 demand elements in 4 dimensions, such as natural environment, supporting facilities, service items and human environment. Then, the Kano model was used to classify the tourists’ demands for forest health care tourism, and the Better-Worse coefficient method was further used to determine the priority of the tourists’ demands for forest health care tourism. The research data came from 430 questionnaires taken by the tourists to the Darong Mountain National Forest Park in Guangxi Zhuang Autonomous Region. Finally, the paper put forward some policy suggestions to improve the tourism demands of tourists for forest health care. (3) Results——According to the Kano model, the tourists’ demands for forest health care tourism in national forest parks can be divided into four types, including 5 essential demands, 7 expected demands, 6 attractive demands and 5 undifferentiated demands. Five demands, including climate temperature, forest coverage, air quality, health and safety, are the essential demands. Seven demands, including accommodation, catering, shopping, transportation, leisure and entertainment, personnel services and sightseeing routes, belong to the expected demands. Six demands, including health care, parent-child education, culture and art, sports wellness, rehabilitation and medical emergency, are the attractive demands. Five demands, including water quality, guidance and interpretation, cultural atmosphere, popularity and consumption level, belong to the undifferentiated demands. According to the Better-Worse satisfaction index analysis method, the Better and Worse values of 23 demand factors are calculated, and the quadrants are established. The priority order is IV>I>II>III. Quadrant IV corresponds to the essential demands, which must first be met. Secondly, it is necessary to fully meet the expected demands of tourists in quadrant I for forest health care tourism. Then, pay attention to the attractive demands of tourists in the second quadrant for forest health care tourism. Finally, the undifferentiated demands of tourists in quadrant III for forest health care tourism can be temporarily ignored. However, after fully meeting the essential demands, expected demands and attractive demands of tourists, the undifferentiated demands should be improved to facilitate their transformation. (4) Conclusions and Discussions——Based on the above research conclusions, the following policy recommendations are put forward: First, meet the essential demands of tourists and lay the service foundation of forest health care tourism. Second, improve the tourists’ expected demands and service quality. Third, enhance the tourists’ attractive demands and innovate the service projects. Fourth, pay attention to the undifferentiated demands of the tourists and promote the transformation of the demands. [ABSTRACT FROM AUTHOR]

(1) Background——Pro-environmental behavior is an important way to realize harmonious co-existence between human and nature. Forest is the ecosystem with the largest land area and the most complete functions. It is of great theoretical and practical significance to explore the relationship between the public perception of forest ecosystem services and their pro-environmental behaviors. (2) Methods——The research data came from 474 valid questionnaires obtained by the research group in April 2023. First, this paper proposed some research hypotheses based on the Self-regulation Attitude Theory and the Cognition-Affection-Attitude-Intention (CAAI) model. Then, the structural equation model was used to explore the relationships between public perception of forest ecosystem services and pro-environmental behavior. Finally, bootstrap analysis was used to test whether the mediating effects of environmental emotion and environmental commitment were significant. (3) Results——The exploratory factor analysis showed that the public perception of forest ecosystem services included 10 measurement items in three dimensions: regulatory services, supply services and cultural services. The standardized parameter estimation results of the structural equation model showed that the public perception of supply services, regulatory services and cultural services of forest ecosystem all had a direct and positive impact on the environmental emotion (β=0. 212, p≤0. 01; β=0. 281, p≤0. 001; β=0. 205, p≤0. 01), and it further confirmed that the individual cognition of the environment was an important prerequisite for emotional arousal. In the relationship between the public perception of forest ecosystem services and the environmental commitment, only the perception of cultural services can directly and positively affect the environmental commitment (β=0. 168, p≤0. 05). The environmental emotion had a significant positive impact on the environmental commitment (β=0. 664, p≤0. 05), which was in line with the relational commitment theory. Moreover, the public pro-environmental behavior was significantly positively affected by the environmental emotion and environmental commitment (β=0. 330, p≤0. 001; β=0. 529, p≤0. 001),in which the environmental commitment had a greater impact on the pro-environmental behaviors, which further expands the research on the internal formation mechanism of the pro-environmental behaviors. The bootstrap test showed that the environmental emotion and environmental commitment played a key mediating role in the process of the impact of the public perception of forest ecosystem services on their pro-environmental behaviors. (4) Conclusions and Discussions——Based on the above research conclusions, the following policy suggestions are put forward: First, on the basis of implementing sustainable forest management and improving the supply quality and efficiency of forest ecosystem services, the government should popularize the value of forest ecosystem services, focus on the aesthetic and health benefits of cultural services. Second, the public media should make full use of real cases to show the negative impact caused by environmental damages, so as to stimulate the public emotional resonance for the natural environment. From the perspective of urban forest construction, the city managers should actively build more parks and community gardens so as to further enhance the public emotional identification with forests. Third, reduce the psychological and physical barriers of the public to change life habits through the establishment of social incentive mechanism and the construction of convenient and comfortable public transportation system and other measures, so as to promote the public pro-environmental behaviors. [ABSTRACT FROM AUTHOR]

Modeling the gravitational field of irregular celestial bodies is a common problem currently faced by the researchers in the fields of Earth science and deep space exploration. This paper reviews the developmental history of gravitational field modeling theory in these two fields. It summarizes research progress in the last decade, focusing on multipole expansion and potential-flow simulation theories. The gravitational field multipole expansion theory introduces the complex algebraic function commonly used in electromagnetism and quantum mechanics to the gravitational field modeling research field, which can express the (internal and external) gravitational field of celestial bodies more concisely. The calculation rules and mathematical tools from the complex function theory make solving the gravitational dynamics problems in Earth and planetary science more convenient. The potential-flow simulation theory is proposed on top of the equivalence of the Earth's external gravitational vector field and the potential-flow velocity field. That is, both are source- and curl-free vector fields. It introduces the numerical algorithms of computational fluid dynamics to model the external gravitational fields of celestial bodies. Because the potential-flow simulation theory is not established based on the perturbation theory, it can overcome the divergence problem of conventional methods, especially when inverting for the gravitational field of an irregularly shaped celestial body. The two theories expand the theoretical research of gravitational field modeling by using seemingly irrelevant knowledge from other research fields, and such methodology is instructive for Earth or deep-space science researchers to make subsequent theoretical improvements. Moreover, we also systematically categorize, compare, and analyze the existing gravitational field modeling methods based on the mathematical definition of the gravitational field, as well as its variants, and summarize their advantages and disadvantages, helping to select proper gravitational field modeling methods for the Earth and deep-space science researchers.

The fine modeling of the lunar gravity field is a fundamental task for establishing lunar altitude references, conducting research on lunar interior structure, and other scientific endeavors. The lunar gravity field model constructed solely based on spacecraft orbit data has limited spatial resolution, making it challenging to meet the demands of fine gravity field research. The acquisition of high-resolution terrain models presents new opportunities for the study of precise lunar gravity fields. This paper reviews the current status and advancements in fine lunar gravity field modeling, including research efforts and evaluation methods for global lunar gravity field models, principles and technologies for fine gravity field modeling, as well as related research outcomes. On this basis, this paper systematically summarizes the key theoretical issues and technical challenges in the theory of lunar gravity field modeling based on high-resolution terrain models. These include data updating, error correction in high-frequency gravity field modeling, calculation efficiency, and the series divergence problem in spherical harmonic analysis. In addition, future research directions are discussed. This work will provide references for gravity field research on the Moon and other terrestrial planets.

As a result of significant advances in geophysics, we have developed a rich arsenal of geophysical methods to infer the internal structure of the Earth. However, the method we could use to infer the internal structure of celestial bodies other than the Earth are still very limited, often relying on geodetic data from orbital probes, landers and astronomical observations. Among these geodetic method, solid tides are of great importance for the study of the celestial bodies' internal structure. Solid tidal deformation and the tidal dissipation provide key information about the internal structure of the rocky celestial bodies, especially the deep structure which contains core-mantle boundary and core. In this paper, we present a comprehensive overview of the research of the deep structure of rocky celestial bodies using solid tidal parameters, including tidal Love numbers and tidal quality factor. First, the basic theory of solid tides, tidal parameters, and viscoelastic models are introduced, and the relationship between the internal structural parameters of the celestial bodies and their solid tidal response is established. This is followed by a review and summary of existing work using solid tide parameters to study the internal structure of the rocky celestial bodies like Mercury, Venus, Mars, and the Moon. Examples include the study of the viscoelastic structure at the base of the lunar mantle using tidal parameters, and the use of tidal parameters to improve the uncertainty of the Martian core radius demonstrate that using solid tidal parameters is an effective method of constraining the deep structure of the celestial bodies. We further provide the contribution of high-precision observations to be acquired by future missions to the study of internal structure. However, there still are some problems in study the internal structure of celestial bodies by solid tidal parameters. For instance, the variability of dissipation strength between different viscoelastic models, the mismatch between short-period experimental data and macroscopic long-period theoretical calculations of viscoelastic models, and so on. We also discuss and analyzes these problems and provides a vision of future research direction.

BACKGROUND: Sarcopenia is a chronic condition that leads to strength loss and functional decline, increasing the risk of frailty, disability, falls, and death in older adults. Blood flow restriction training can be effective in the treatment of sarcopenia, but a comprehensive review of its advantages, disadvantages, biological mechanisms, and application options is lacking. OBJECTIVE: To review the advantages, limitations, and biological mechanisms of blood flow restriction training interventions for sarcopenia and to give recommendations for application protocols based on current published evidence. METHODS: A search of major databases was conducted for literature published in the time frame up to February 2023. The search terms were “blood flow restriction training, KAATSU, elderly, sarcopenia, muscle” in English and Chinese. Finally, 82 included papers were compiled and analyzed. RESULTS AND CONCLUSION: Blood flow restriction training as an intervention for sarcopenia has been effective in peripheral muscle groups, but there are limitations in its application. Blood flow restriction training is highly operational and safe. This training can improve muscle strength and physical performance, but there are potential risks, including adverse events on skeletal muscle, cardiovascular and endothelial cells. Therefore, blood flow restriction training needs to be performed under scientific guidance and further studies are needed to verify its efficacy in patients with sarcopenia. The biological mechanisms of blood flow restriction training intervention in sarcopenia may include: increasing muscle hypertrophy due to reactive muscle congestion, improving muscle protein synthesis capacity, inducing metabolic stress adaptation, promoting skeletal muscle growth and repair, activating vascular endothelial growth factor signaling pathway to promote angiogenesis, and promoting satellite cell proliferation. However, these specific roles and combined effects of these mechanisms need to be determined by more in-depth studies. Blood flow restriction training interventions for sarcopenia are mainly influenced by training and cuffs. To avoid adverse events, it is recommended that 20% to 50% 1RM, 20 to 75 repetitions, 2 to 3 times per week, 30-60 seconds interval between sessions, smaller size cuffs with a pressurization value ≤ 140 mmHg for upper limb training, and larger size cuffs with a pressurization value ≤180 mmHg for lower limb training, usually 50% to 80% of the pressure value in the completely occluded artery. However, more research is needed on the training frequency and interval between sessions in older adults, and further research is needed on the optimal choice of cuff pressurization values. [ABSTRACT FROM AUTHOR]

BACKGROUND: Clinical use of vascular stents involves high medical costs, but it may also bring long-term benefits in reducing cardiovascular events and improving the quality of life in patients. Economics evaluation can help decision makers better understand the balance between the cost and benefit of treatment. OBJECTIVE: To analyze the related articles of health economics and discuss the hot spots in the study of the effect and problems of vascular stents in medical quality management. METHODS: The articles concerning health economics evaluation of vascular stents were retrieved from the core set of the Web of Science. The VOSviewer_1.6.19 software was used to make a visualization analysis of the annual publication volume, institutions, countries, keywords, etc. Finally, the research hot spots on the effects and problems of vascular stents were analyzed from the perspective of health economics and medical quality management. RESULTS AND CONCLUSION: (1) 120 articles in English were finally included. In the past 10 years, the highest number of articles published in this field was in 2019, with 10 articles. The institution with the largest number of articles published was Harvard University in the United States with 20 articles, and the country with the largest number of articles published was the United States with 58 articles. (2) Keyword cluster analysis demonstrated that the cost-effectiveness analysis of bare metal stents and drug-eluting stents in coronary disease, the cost-effectiveness analysis of angioplasty stent intervention, and the effect of coronary stents in percutaneous coronary intervention are the research hot spots in the field of health economics evaluation of vascular stent research. (3) In the context of medical quality management, the paper further summarized the research hot spots on the therapeutic effect of vascular stents as follows: long-term effect of vascular stents, safety, drug release mechanism research, personalized therapy, restenosis problems, and stent insertion technology. (4) The results of highly cited literature analysis exhibited that drug-eluting stents release drugs to reduce the risk of vascular restenosis, and the restenosis rate is lower than that of bare metal stents, but the cost is usually higher. Biodegradable stents combine the advantages of bare metal stents and drug-eluting stents, that is, avoiding long-term stent existence and reducing the risk of restenosis, but their cost may be higher, and there may be some complications in the short term, and they are not widely used at present. (5) In addition to the direct stent cost, factors that need to be considered when comparing the cost-effectiveness of vascular stents include the risk and cost of stent re-intervention, the risk and cost of complications, the duration and cost of drug therapy, and the quality of life of patients. Therefore, while the initial cost of drug-eluting and biodegradable stents may be higher than bare metal stents, they may lead to better clinical outcomes in the long term, resulting in a more favorable cost effect. (6) Future research directions should focus on making personalized vascular stent treatment decisions, observing the long-term effect of stent treatment, the impact of the stent on patients’ quality of life, formulating health policies, rational allocation of medical resources, and the establishment of long-term follow-up mechanisms. [ABSTRACT FROM AUTHOR]

In this paper, the generation of the single harmonic light source is studied by using chirp waveform control and two-color waveform control. The results show that, in the case of the chirp waveform control, the adjustable range of the single harmonic light source is from 170th order to 370th order, and the energy adjustable range is wide. Moreover, the requirement of the single harmonic generation is not the very high to the laser duration and laser intensity. In the case of two-color waveform control, the adjustable range of the single harmonic light source is only from 80th order to 110th order, and the energy adjustable range is narrow. Moreover, the requirement of the single harmonic generation is a little bit high to the laser duration and laser intensity. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Three isotropic heteropoly acid ionic liquid models were constructed, and their microstructures, binding energies and carrier effective masses were analyzed and discussed in the framework of density functional theory. The results show that the number of substituted coordination atoms of heteropoly acid has a great influence on the properties of the compound. In molybdenum-substituted phosphotungstic acid, when the number of molybdenum-substituted phosphotungstic acid is low, the effective mass of the hybrid carrier is low and the conductivity is strong. With high molybdenum substitution number, the carrier’s relative mass is larger, so the transmission resistance increases, and its conductivity is better than that of the complexes with low molybdenum substitution number. This paper predicts and verifies the properties of the synthesized materials, and provides theoretical basis and guidance for the synthesis and analysis of this kind of materials in the future. [ABSTRACT FROM AUTHOR]

In order to explore the stability of cluster NiPS3 and the mechanism of isomerization transformation, in this paper, density functional theory was used to optimize the initial configuration of cluster NiPS3 and calculate the isomerization under the quantum chemistry calculation level of B3LYP/def2-tzvp. Ten optimal configurations and seven isomerization transformation types were obtained. Based on the thermodynamics and kinetics of chemical reactions, the following conclusions are drawn: the isomerization transformation of cluster NiPS3 depends on the bonding and bonded breaking between non-metal and non-metal. The greater the difference between the stability of reactants and products, the more thorough the reaction. Except reaction 2(2)→1(4), other isomerization reactions are more spontaneous at low temperature. The isomerization reaction tends to proceed in the forward direction, that is to say, the higher energy configuration is easier to convert to the lower energy configuration. Configurational 1(2), configurational 2(2) and configurational 1(4) are the final products of cluster NiPS3 isomerization, and could be given priority in the research, development and production of related materials. [ABSTRACT FROM AUTHOR]

The misuse of metronidazole（MNZ） has caused serious pollution of the water environment. In this paper, the adsorption effects of MNZ on single-walled carbon nanotube（CNT） and Fe doped carbon nanotube（Fe-CNT） were studied by first-principles calculation. The adsorption structure, adsorption energy, electron orbital, charge transfer and state density of single-walled CNT and Fe-CNT and MNZ were calculated respectively. The results show that the original CNT has a weak adsorption effect on MNZ, while the interaction between Fe-CNT and MNZ is significantly enhanced. Therefore, Fe-CNT is expected to be candidates for adsorbing the water contaminant MNZ. [ABSTRACT FROM AUTHOR]

In this paper, electronic structures and photocatalytic performances of Si, Ge, Zr and Sn doped SrTiO3 were studied using density functional theory realized by QUANTUM ESPRESSO（QE） software package. The lattice constants of SrTiO3 obtained by using the generalized gradient approximation（GGA） are very consistent with the previous experimental data. At the same time, the lattice constants of SrTi0.875X0.125O3（X=Si, Ge, Zr, Sn） doped systems were obtained. The band gap values of SrTiO3 and SrTi0.875X0.125O3（X=Si, Ge, Zr, Sn） are 1.853 eV, 1.849 eV, 1.916 eV, 1.895 eV and 1.925 eV, respectively. When studying the photocatalytic performance of five SrTiO3 systems, the band gap values of the five SrTiO3 systems were modified by using the scissors operator. The reduction potential(ECB) of the conduction band edge of the intrinsic SrTiO3 and four SrTi0.875X0.125O3（X=Si, Ge, Zr, Sn） doping systems were calculated to be-0.782 eV,-0.736 eV,-0.776 eV,-0.800 eV and-0.791 eV, respectively. The oxidation potentials(EVB) of the valence band edge corresponding to five SrTiO3 systems were calculated as 2.418 eV, 2.460 eV, 2.487 eV, 2.442 eV and 2.481 eV, respectively. From the perspective of redox properties, the redox properties of the two SrTi0.875X0.125O3（X= Zr, Sn） doping systems are improved compared with the intrinsic SrTiO3, while the redox property of SrTi0.875Si0.125O3 is reduced compared with the intrinsic SrTiO3. The relative positions of the band edges of the five SrTiO3 systems can meet the process of water splitting to generate H2 and O2.  [ABSTRACT FROM AUTHOR]

In this paper, based on Hill dynamics and Michaelis-Menten equation, a theoretical model is established to study the noise effect in the coupled oscillation of genes and proteins between two cells. We found that in the Notch signaling pathway, the coupled oscillations of genes and proteins between two cells exhibit periodic oscillation characteristics, indicating the synchronous oscillation characteristics of intercellular signaling. "Intrinsic" noise and "external" noise have different effects on the coupled oscillation of genes and proteins between two cells. The internal noise is beneficial to increase the expression of genes and proteins in the intercellular Notch signaling pathway again. The expression levels of genes and proteins in external noise-induced pathways decrease, and periodic oscillations become damped. The combined action of internal and external noise can not only make gene expression appropriate and present a continuous oscillation pattern, but also make the corresponding protein process of gene transcription and synthesis between cells show a continuous oscillation mode. It shows that the internal and external noise of gene expression is beneficial to control the gene activation between cells and maintain the periodic rhythm of protein synthesis. The theoretical results in this paper reveal a regulatory mechanism of internal and external noise on the dynamics of the intercellular Notch signaling pathway. The respective regulatory effects of internal and external noise can be determined by our calculations, which clarify the physical mechanism of the continuous periodic oscillation of the regulation system under the combined effect of internal and external noise. The theoretical results are consistent with the experiments. It can provide a theoretical basis for the design of pathway therapies to prevent various diseases and cancers caused by Notch system gene and protein mutations. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The mining of thin coal seam resources is seriously affected by the overlying coal seam gas. The detection of three zones of goaf roof is of great significance to the safety production. In this paper, we carried out loading coal and rock resistivity testing experiment, analyzed the loading damage in the process of coal and rock resistivity change and distribution, and carried on the theoretical analysis and numerical simulation of overlying strata three zones according to the actual embedded depth, and then carried out field test. Direct current method has been used to test the forward three-zone apparent resistivity distribution. The main conclusions are as follows: the resistivity changes due to the crack propagation of coal samples, and the resistivity surge point corresponds well with the failure point of coal and rock; in the process of coal and rock failure under load, there are abnormal areas in the resistivity cloud diagram under load, and it migrates with the uneven deformation of coal and rock under load; the collective subsidence of the goaf after the roof is cut in the coal seam mining will form a large sectioned area in thefracture area of the upper part of the goaf. There are large cracks in this part of the sectioned area, and it will extend to the roof rock of the return air roadway, resulting in the increase of cracks in the rock; the electrical detection results show that the horizontal distance from the working face to the caving zone is about 20 m, and the influence resistance value of the fracture zone becomes larger and its height is 17 m, which is consistent with the theoretical calculation and numerical simulation results.

The stress of surrounding rock is closely related to the distribution of plastic zone. In this paper, the maximum principal deviatoric stress is taken as the index, and the maximum principal deviatoric stress distribution of surrounding rock considering axial stress is deeply studied through theoretical analysis, and the correctness of theoretical analysis is verified by numerical simulation. The results show that: under different lateral pressure coefficients, the maximum principal deviatoric stress will show three forms: circular, elliptical and butterfly. When the lateral pressure coefficient is 1, the maximum principal deviatoric stress is a standard circular shape; with the increase of the lateral pressure coefficient, the maximum principal deviatoric stress gradually changes from circular to elliptical and then to butterfly and butterfly; under the same stress environment, there is a one-to-one correspondence between the plastic zone shape of roadway surrounding rock and the maximum principal deviatoric stress shape. The distribution of the maximum principal deviatoric stress can reflect the shape of the plastic zone to a certain extent; based on the correspondence between deviatoric stress and plastic zone, the stability of deep roadway in Kouzidong mine is analyzed, and the suggestions of roadway support control are proposed.

The weathering at the top of bedrock in Jurassic coalfield in northern Shaanxi is strong, and the formed weathered bedrock aquifer is the main water filling source of the mine, which poses a serious threat to the safe mining of the mine. The scientific evaluation of the water abundance of the weathered bedrock aquifer and the advanced drainage of the areas with strong water abundance are essential measures for preventing and controlling water disasters of the roof weathered bedrock. In this paper, taking Nanliang Coal Mine as an example, according to the drilling data, the weathering index, core recovery rate, brittle-plastic rock thickness ratio and rock structure index are selected to construct the evaluation system. The fuzzy analytic hierarchy process and coefficient of variation method are used to weigh comprehensively, and the water abundance of weathered bedrock aquifer in Nanliang Coal Mine is evaluated. The results show that the weathering degree of bedrock in Nanliang Coal Mine is strongly affected by ancient terrain, and the underlying Quaternary gully controls the thickness of the bedrock weathering zone. Combined with the evaluation results of mine water inrush status, the water inflow in the water-rich area is large.

The light scattering method is widely used in the field of dust detection, and the core of the technology is the detection error. In order to further reduce the detection error of dust concentration, a light scattering multi-source coupling dust concentration detection technology is proposed in this paper. The study analyzes the basic principle of MIE light scattering, mathematically deduces the light scattering multi-source coupling theory, determines the two optimal angles of light scattering, and develops the light scattering multi-source coupling dust concentration detection unit and prototype. Based on the test preparation and system, the photoelectric sensors 1 and 2 of the prototype are tested. The multi-source data coupling method is used to couple the AD values of the photoelectric sensors 1 and 2, and a dust concentration detection algorithm is proposed to form the light scattering multi-source coupled dust concentration detection technology. The test found that the detection relative error of the light scattering multi-source coupling prototype is less than 9.5%, which is 4.7% smaller than that of photoelectric sensor 1 and 4.9% smaller than that of photoelectric sensor 2. It is proved that the relative error of the light scattering multi-source coupling prototype is reduced by 4.7% compared with the single-angle detection.

The balance valve has the advantages of good load holding function and pipeline burst or serious leakage to prevent the uncontrolled occurrence of moving load. However, when the rescue truck mounted drilling rig is used for the lifting system, due to the large weight of the supporting drilling tools of the rescue drilling rig, the reasonable matching of the balance system is a design problem. In this paper, the scheme of balanced speed regulation system plus forced oil replenishment system is proposed. The balanced speed regulation system realizes the stable and controllable lowering speed. Forced oil replenishment can effectively prevent air suction and improve the safety and service life of the feeding system. The overbalanced hydraulic system is analyzed theoretically, and then the system dynamic model is established. Based on this model, the pressure and flow characteristics of the overbalance system are dynamically analyzed, the influence of the parameters of the balance valve on the dynamic characteristics of the feed and pull-out system is emphatically analyzed, and the parameter matching method of the overbalance system is proposed. The theoretical analysis results are verified by bench test. The results show that the weight of drilling tools has a great impact on the output of the conventional balance system. Setting the over balance speed regulation system in the feed and pull-out system of the drilling rig and reasonably matching the over balance parameters can realize the output stability of the feed and pull-out system and avoid the problems of air suction and out of control of speed.