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A new adsorbent(DES@ZIF@MG) was prepared by grafting deep eutectic solvents(DES) onto metal organic framework ZIF/magnetic reduced graphene oxide(MG) for the adsorption of methamphetamine. A series of structural characterization analyses (SEM, FT-IR, BET, VSM, TGA) were facilitated to explore the microscopic morphology and physicochemical properties of DES@ZIF@MG. The adsorption performances of methamphetamine onto the adsorbent were investigated by adsorption kinetics, isotherms, and adsorption effect experiments(pH, ionic strengths, and humic acid). The results showed that the adsorption of methamphetamine onto DES@ZIF@MG was consistent with the pseudo-second-order model and the Langmuir model, indicating that the adsorption process was an energetically homogeneous adsorption dominated by chemisorption. The XPS characterization illustrated that the adsorption process of methamphetamine by DES@ZIF@MG mainly involved hydrogen bonding, π-π interaction, electrostatic interaction, and chelation.

When faults such as blocking and commutation failure occur in a high-voltage direct current （HVDC） transmission system， they can cause transient voltage fluctuations near the sending-side converter station and lead to the disconnection with power grid. Firstly， the operating principles， response characteristics， and key parameter influences of the grid-forming energy storage open-loop control strategy are analyzed. Then， the reactive response characteristics of the synchronous condenser are analyzed， and a comparison is made between the grid-forming energy storage reactive power control model and the excitation regulation control model. Finally， a semi-physical simulation system is established， including EHVDC， photovoltaics， synchronous condenser， and grid-forming energy storage， to conduct comparative experiments on the effect of suppressing AC transient overvoltage under DC commutation failure. The results indicate that grid-forming energy storage and distributed synchronous condenser with the same capacity can achieve similar effects in terms of reactive transient response speed and the ability to suppress AC transient overvoltage.

The grid-forming （GFM） control technology is instrumental in enabling converters to provide frequency and voltage support response akin to synchronous generators， thus bolstering the stability of the new power system. Nonetheless， a notable challenge lies in delivering grid support during fault current limiting. To this end， a strategy for fault current limiting in GFM converters based on measuring terminal and internal differential voltage orientation is proposed. In this approach， the angles of the positive and negative sequence current commands lag 90° behind the positive and negative sequence voltage differences. Additionally， the maximum magnitude of the synthesized vector of the current commands aligns with the converter’s overcurrent capability， which is equivalent to the generation of positive and negative sequence adaptive virtual inductance by control， respectively. This method obviates the need for direct virtual inductance value calculations and can maximize the maximum support capacity of the converter to realize the fault current characteristics resembling those of synchronous generators. The proposed fault current limiting strategy is validated by a simulation system built through PSCAD/EMTDC. The simulation outcomes affirm the strategy’s efficacy in delivering substantial grid support to the AC system while limiting fault currents.

C27H39N3O2Sn, monoclinic, P21/c (no. 14), a = 10.3317(6) Å, b = 15.8067(9) Å, c = 16.5497(9) Å, β = 90.5380(10)°, V = 2702.6(3) Å3, Z = 4, Rgt(F) = 0.0370, wRref(F2) = 0.0954, T = 296(2) K.

Cold stimulation and exercise are two independent stimulus variables, each yielding unique impacts on human health. However, in many cases, individuals often encounter both factors simultaneously, particularly in colder regions where outdoor physical activity is prevalent. Despite numerous studies exploring the effects of cold exposure and exercise independently, only a limited number of comprehensive reviews have evaluated their combined influence on health. This review aims to bridge this gap by meticulously examining the potential benefits and detriments of both cold stimulation and exercise on human health. Specifically, the review focuses on their impacts on cardiovascular, respiratory, and immune function, as well as the favorable effects of moderate exercise on the human body. While evidence suggests that cold exposure can enhance health outcomes in certain disease contexts, it also poses risks, particularly for vulnerable populations. Furthermore, while moderate exercise is generally beneficial, engaging in physical activity in cold weather conditions can increase the risk of hypothermia, frostbite, and other cold-related injuries. Consequently, there is an urgent need to develop safe and effective guidelines for exercising in cold weather, particularly for individuals living in colder regions. This review emphasizes the necessity for further research on the combined effects of cold stimulation and exercise, with the goal of informing public health policies and guidelines for physical activity in cold weather conditions.

In order to make the temporary support force better adapt to the mine pressure and improve the support capacity of the support, taking the dual self-moving temporary support as the research object, an adaptive control method of temporary support force based on particle swarm optimization (PSO) - BP neural network is proposed. The initial weights of the BP neural network are optimized by using the global search capability and fast convergence features of the PSO algorithm to improve the rate of convergence of the BP neural network. Then, the optimized BP neural network is used to achieve online self-adjustment of PID parameters. The PSO-BP neural network is constructed to optimize the PID controller. This enables the temporary support force to reach the predetermined value more quickly and accurately, achieving adaptive control of the temporary support force. It avoids damage to the roof due to the mismatch between support force and roof pressure. The expected initial support force of the temporary support is simulated using unit step signals for experimental verification. The results show that compared with the BP neural network optimized PID controller and traditional PID controller, the PSO-BP neural network optimized PID controller can achieve the expected initial support force faster and more accurately. The adjustment time is only 0.5 s and there is almost no overshoot. Based on actual geological conditions, the roof pressure on the support during excavation support is simulated. The adaptive control effect of three controllers for support force is studied. The results show that under the control of the PSO-BP neural network optimized PID controller, the system error is only 0.02 MPa, with the smallest error and the best control effect.

The key to grasping and practicing the important concept of “green mountains are golden mountains” is to internalize the construction of ecological civilization into the operation mechanism of the market economy and to stimulate the endogenous motivation of the whole society to engage in the construction of ecological civilization. The study focuses on the value of forest ecological products in Fujian Province and evaluates these products from four perspectives: support services, regulating services, supply services, and cultural services. Subsequently, we constructed the suitability evaluation index system for the realization mode of forest ecological product value in Fujian Province. We weighted the indexes by combining the entropy value method and the expert scoring method, and evaluated the suitability of the realization mode using the structural equation model. The suitability assessment results show that Zhouning County, Ningde City - ecological compensation > Shunchang County, Nanping City - ecological tenure trading > Changting County, Longyan City - ecological restoration > Jiangle County, Sanming City - ecological industrialization model. The regression estimates of ecological product production potential factor (β=0.221, p

Summary at a glance: The 6-min walk test (6MWT) is a widely used field walking test. This study reports the normative reference values (NRV) of distance walked during 6MWT (6MWD) in healthy Singaporeans (aged 21–80) and updates the 6MWD reference equations. This information may facilitate the interpretation of the 6MWD in clinical populations. Ethics approval: The Singapore Institute of Technology-Institutional Review Board (SIT-IRB Project Number: 2019099) approved this study to be carried out from June 2019 to January 2021. All participants gave written informed consent before data collection began. Background: The six-minute walk test (6MWT) is a widely adopted submaximal field-walking test to evaluate functional exercise capacity. This validated test is a reliable, safe, inexpensive, and straightforward assessment tool commonly used as an outcome measure, using the distance walked (6MWD) as the primary outcome. An earlier study has established the normative reference values (NRV) and equation in healthy Singaporeans — however, the small sample size and narrow age range curb adequate representation of the adult population profile. Objectives: This study aims to update the NRV and reference equations to predict the distance walked during 6MWT (6MWD) for healthy Singaporeans aged 21–80. Methods: This cross-sectional study recruited community-dwelling healthy subjects aged 21–80 via convenience sampling. Each subject completed two trials of 6MWT according to the standard protocol. Primary outcome measures included 6MWD, pre-and post-test heart rate (HR), oxygen saturation, and blood pressure (BP). Results: 172 healthy Singaporeans ([Formula: see text], [Formula: see text]) participated. The overall mean 6MWD was [Formula: see text] metres. The age-stratified mean 6MWD ranged from [Formula: see text] metres (aged 21–39) to [Formula: see text] metres (aged 60–80). Age, gender, and percentage maximum HR predicted (%PredHRmax) were the most significant variables ([Formula: see text]). 6MWD reference [Formula: see text] [Formula: see text] (HR reserve, bpm) [Formula: see text] (weight, kg), [Formula: see text]. Applying equations from other studies to the Singaporean population resulted in an overestimation of the 6MWD. Conclusion: This study updated the NRV and reference equations of 6MWD for healthy Singaporeans aged between 21–80 years. This update revises the local benchmarks of 6MWD in Singapore, a widely adopted outcome measure.

Advances in the field of processing and characterization of material behaviors are driving innovations in materials design at a nanoscale. Thus, it is demanding to develop physics-based computational methods that can advance the understanding of material Multiphysics behaviors from a bottom-up manner at a higher level of precision. Traditional computational modeling techniques such as finite element analysis (FE) and molecular dynamics (MD) fail to fully explain experimental observations at the nanoscale because of the inherent nature of each method. Concurrently coupled atomic to the continuum (AtC) multi-scale material models have the potential to meet the needs of nano-scale engineering. With the goal of representing atomistic details without explicitly treating every atom, the AtC coupling provides a framework to ensure that full atomistic detail is retained in regions of the problem while continuum assumptions reduce the computational demand. This review is intended to provide an on-demand review of the AtC methods for simulating thermo-mechanical behavior. Emphasis is given to the fundamental concepts necessary to understand several coupling methods that have been developed. Three methods that couple mechanical behavior, three methods that couple thermal behavior, and three methods that couple thermo-mechanical behavior is reviewed to provide an evolutionary perspective of the thermo-mechanical coupling methods.

In the detection of wire rope damage, the structure design of the flaw detector is very important to the detection precision of wire rope damage. The research on the structural parameters and their combinations of the existing electromagnetic wire rope flaw detector is insufficient. In order to solve the above problems, an optimization method of structural parameters of wire rope flaw detector based on orthogonal test is proposed. Based on the theoretical mathematical model of magnetic field distribution of radial magnetic ring and the theoretical model of the equivalent magnetic circuit, the structural parameters affecting the detection precision of wire rope flaw detector are analyzed and obtained. The parameters include the length of the magnet, the thickness of the magnet, the thickness of the armature, the length of the armature and the chamfer parameter. The influence grade and significance of each parameter are studied by the orthogonal test. The influence grade of each parameter factor on the detection precision of the wire rope flaw detector is the thickness of the magnet, the length of the magnet, the length of the armature, the thickness of the armature and the chamfer. The thickness of the magnet, the length of the magnet and the length of the armature have significant effects. These should be given priority when designing the wire rope flaw detector. The thickness of the armature and the chamfer are not significant and can be ignored. The influence of the thickness of the magnet and the length of the magnet is positively correlated with the increase of level. With the increase of the thickness of the magnet and the length (＜70 mm) of the magnet, the detection precision will be significantly improved. The length of the armature shows a negative correlation trend as a whole. The longer the length, the worse the detection precision. According to the analysis results, the optimized values of the parameters of the steel wire rope flaw detector are determined. The magnetic line distribution, the magnetic field distribution and the radial and axial phase magnetic induction intensity distribution of the steel wire rope flaw detector before and after the optimization are compared and verified. The results show that the optimized steel wire rope flaw detector based on the orthogonal test has uniform magnetic flux distribution. The excitation effect of steel wire rope is more than 2 T. The magnetic flux leakage signal is obvious. The damage signal under different phases is quite different. Compared with the steel wire rope flaw detector before optimization, the steel wire rope flaw detector has the following advantages. The magnetic flux leakage intensity is greatly improved. The spatial distribution is obviously improved. The requirements for the position (lift-off value) of the sensor are relatively broad. The radial detection precision is improved by about 40%, and the axial detection precision is improved by about 80%. The perception effect on the damage of the steel wire rope is obviously improved.

The magnetic flux leakage(MFL) detection method is the most widely used method for detecting the mine wire rope damage, and there is no research on the influence of magnetic noise signal in magnetic flux circuit on the MFL detection signal of wire rope damage. Based on the principle of MFL detection for wire rope damage, the equivalent magnetic circuit model of MFL detection is constructed, and the magnetic field distribution of the magnetic flux circuit is simulated by Ansoft Maxwell finite element software. The results show that there are many magnetic noise circuits in the magnetic flux circuit besides the main magnetic flux and the MFL of wire rope damage, which are easy to interfere with the MFL detection signal of wire rope. The MFL of armature magnetic conduction path and the coupling MFL between permanent magnets on both sides and air medium have the greatest influence. Based on the simulation results, the magnetic flux circuit is optimized. The contact part between the armature and the permanent magnet is changed from a right-angle structure to a rounded structure to reduce the MFL at this part, increase the main magnetic flux in the armature magnetic conduction path, and then enhance the MFL detection signal of wire rope damage. The annular magnetic bridge circuit shielding device is designed with high magnetic conductivity material and installed in the damage MFL detection area so as to guide the direction of the coupling MFL between the permanent magnets on both sides and the air medium, and reduce the influence of the coupling MFL on the detection of wire rope damage MFL. The experimental results show that after the optimization of the magnetic flux circuit, the characteristics of the wire rope damage detection signal are more obvious than those before the optimization, and the collected signal increases from 6.14 mV to 18.59 mV. It is verified that the optimization scheme can improve the transmission efficiency of the magnetic flux circuit, have the aggregation and enhancement effect on the damage MFL, and reduce the superposition effect of the permanent magnet-air coupling MFL and the wire rope damage MFL, which is conducive to improving the accuracy of wire rope damage detection.

Globally, Prostate cancer (PCa) is the second most common cancer in the male population worldwide, but clinically significant prostate cancer (CSPCa) is more aggressive and causes to more deaths. The authors aimed to construct the risk category based on Prostate Imaging Reporting and Data System score version 2.1 (PI-RADS v2.1) in combination with Prostate-Specific Antigen Density (PSAD) to improve CSPCa detection and avoid unnecessary biopsy. Univariate and multivariate logistic regression and receiver-operating characteristic (ROC) curves were performed to compare the efficacy of the different predictors. The results revealed that PI-RADS v2.1 score and PSAD were independent predictors for CSPCa. Moreover, the combined factor shows a significantly higher predictive value than each single variable for the diagnosis of CSPCa. According to the risk stratification model constructed based on PI-RADS v2.1 score and PSAD, patients with PI-RADS v2.1 score of ≤2, or PI-RADS V2.1 score of 3 and PSA density of

Objective To obtain induced pluripotent stem cells (iPS) and cardiac myocyte-like cells (CMs) from a patient with noncompaction of ventricular myocardium (NVM). Methods Urine cells from a 16-year-old female patient with NVM and a 24-year-old healthy male volunteer were infected with Sendai virus to obtain iPS cells, which were further induced to differentiate into iPS-CMs. Both the iPS cells and iPS-CMs were identified by immunofluorescence staining, alkaline phosphatase activity, karyotype analysis, embryoid body (EBs) formation and cell patch-clamp experiment. Whole-exome sequencing of the blood sample, iPS cells and iPS-CMs from the NVM patient was performed for genetic comparison to identify gene mutations potentially related with NVM. Results We successfully obtained urine cells, iPS cells and iPS-CMs from the NVM patient and the healthy volunteer. Immunofluorescence assay showed that the iPS cells expressed pluripotent stem cell markers Oct4, Sox2, Ssea4 and TRA-1-81. iPS cells exhibited a high alkaline phosphatase activity with a normal karyotype, and could be induced to differentiate into 3 germ layers in vitro. Immunocytochemical staining revealed that iPS-CMs expressed cardiac myocyte-specific markers TNNT2 and α-actinin. Patch-clamp experiment demonstrated the presence of functional cardiac-specific voltage-gated Na+ currents and action potentials in the iPS-CMs. Whole-exome sequencing showed similar genetic profiles between the blood samples, iPS cells and iPS-CMs of the NVM patient, and several gene mutations were found to have potential associations with NVM. Conclusion We successfully obtain iPS cells and iPS-CMs from the NVM patient, and these cells provide useful cell models for the study of NVM using iPS technology.

In view of problem that current wire rope flaw detector cannot accurately detect whether the wire rope is damaged or not, a mine-used wire rope flaw detector based on Hall elements was designed according to magnetic flux leakage detection method. Permanent magnet magnetization wire rope is adopted. When the wire rope is damaged, there will be magnetic leakage at the damaged part. Hall element is used to collect magnetic leakage signal at the damaged part of the wire rope, and by analyzing output voltage waveform of Hall element it is determined whether the wire rope is damaged or not. In order to further improve detection accuracy of wire rope flaw detector, axial, circumferential and radial arrangement of the Hall element is optimized: uses Ansoft Maxwell to simulate magnetization condition of wire rope, the axial arrangement of Hall elements is determined based on simulation results, and the axial position of the Hall element is selected in center of the flaw detector. In order to eliminate inter-strand effect of wire rope, the circumferential arrangement of Hall elements is calculated and designed. The inter-strand effect can be basically eliminated when circumferential distance between two detection points is 29 mm. The radial arrangement of Hall element is studied by changing lifting distance through experiment. There will be jitter during movement of the wire rope, in order to prevent equipment from being damaged due to contact between the wire rope and the Hall element, the appropriate lifting distance should be selected to arrange the Hall element according to jitter of the wire rope. The experimental results show that the flaw detector can accurately detect whether the wire rope has damaged or not according to the signal mutation at the wire rope damage.

C20H18F2N2, monoclinic, P21/c (no. 14), a = 12.4233(11) Å, b = 7.3805(7) Å, c = 18.9531(16) Å, β = 104.109(3)°, V = 104.109(3) Å3, Z = 4, Rgt(F) = 0.0464, wRref(F2) = 0.1201, T = 296(2) K.

In order to ensure the safe operation of steel wire rope,it is necessary to carry out periodical nondestructive testing.In the existing method of wire rope detection,electromagnetic detection based on magnetic flux leakage principle is recognized as the most practical detection method.The existing magnetic flux leakage detection method is difficult to achieve the expected saturation magnetization,the detection result is low in stability and reliability,and the detection equipment is bulky.Due to the problems and shortcomings of leakage detection method which is widely used,a new detection method called multiloop magnetic method.The numerical simulation research based on Ansoft has been established.The traditional test and the proposed approach have been analyzed.Through the comparison and analysis of the simulation results,it indicates that this multiloop magnetic method breaks the limitations of traditional testing methods.The method has better practicability and accuracy.

In order to realize automatic cutting with high precision and autonomous cruising of tunneling equipments, a analysis method of automatic cutting section boundary control error for longitudinal roadheader was proposed. The error sources of automatic cutting control system for roadheader had been made clear, which were mainly from steady-state error of control system, sensor precision, inertia of cutting arm, system control method and other non-theoretical calculation factors. The system was simulated and the results showed that influence of load disturbance on system steady-state characteristics was low and the system was stable. Each error was calculated and the maximum error of automatic cutting section boundary control was 71.30 mm in horizontal and 55.27 mm in vertical, which showed that the system fully met the highest standard of Standard for Quality Inspection and Assessment of Shaft Sinking and Drifting of Coal Mine. Through ground tests of automatic cutting control for roadheader, the maximum error of section boundary control was 45 mm in horizontal and 12 mm in vertical in actual measurement.

An analysis method was proposed for dynamic characteristics of automatic cutting and profiling control system for roadheader base on transfer function model. Composition and main structure of the system were expounded, and transfer function model of each part of the system was obtained. Dynamic characteristics of the system were simulated when cutting head moved horizontally. The simulation results show that the transfer function of the system is an open-loop transfer function which is composed of proportional, integral and two order oscillation, and the system is a type I system; when adjustable gain is 14, the system outputs a good response with no overshoot and smooth curves, the shorter rising time is 0.428 s, and adjusting time is 0.797 s; the system has no zero point, and characteristic roots are in the left half of S plane with a positive amplitude margin and a phase margin, which shows the system has good stability. The field test shows that vertical cutting error of the cutting head is less than 40 mm, unilateral positioning precision of cutting tunnel section is less than 50 mm as well as repeatability precision is less than 20 mm.