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Abstract Background The role of red blood cell (RBC) counts as potential independent risk factors for deep vein thrombosis (DVT) in patients with spinal cord injury (SCI) remains uncertain. This study aims to clarify the associations between RBC counts and DVT incidence among this population. Methods A retrospective analysis was performed on 576 patients with SCI admitted to the rehabilitation medicine department from January 1, 2017 to December 31, 2021. After exclusions, 319 patients were analyzed, among which 94 cases of DVT were identified. Results Mode of injury, D-dimer and anticoagulant therapy were significant covariates (P

The medium of X65 steel injection sea pipe contains dissolved oxygen, causing severe corrosion inside the pipeline. Regarding this issue, based on the basic data of the on-site water injection subsea pipeline, considering the effects of flow rate, temperature, dissolved oxygen and Cl- concentration on the corrosion behavior of X65 steel, 9 sets of orthogonal tests were designed, and the weight loss test and corrosion product characterization were carried out by using high temperature autoclave, scanning electron microscope and X-ray diffractometer. Combined with multiple linear regression method, a corrosion prediction model was established. Results showed that the order of the degree of influence of the four influencing factors on corrosion rate from large to small was: dissolved oxygen concentration > temperature > flow rate> Cl- concentration, and dissolved oxygen concentration was the main control factor of corrosion. The corrosion rate increased with the increases of flow rate, temperature, dissolved oxygen concentration and Cl- concentration. The characterization results of corrosion products showed that the corrosion products were mainly Fe3O4 and Fe2O3. Considering the influence of the above four factors, a corrosion prediction model was established based on seven groups of uniform corrosion rate values. Furthermore, the remaining two groups of uniform corrosion rate values were used to validate the corrosion prediction model, and the maximum error was 8.9%, indicating that the corrosion rate prediction model was accurate.

To determine the definition, foundation, practice, and development of evidence-based rehabilitation medicine (EBRM) and point out the development direction for EBRM. Retrieve the database of PubMed, Cochrane Library, Embase, China national knowledge infrastructure (CNKI), Wanfang, and China science and technology journal database (CSTJ). The search was conducted from the establishment of the database to June 2023. The key words are “rehabilitation medicine and evidence based” in Chinese and English. After reading the abstract or full text of the literature, a summary analysis is conducted to determine the definition, foundation, practice, and development of EBRM. A total of 127 articles were included. The development of 14 sub majors in EBRM are not balanced, evidence-based musculoskeletal rehabilitation medicine (EBMRM) (31 articles, mainly focuses on osteoarthritis, osteoporosis and musculoskeletal pain), evidence-based neurorehabilitation medicine (EBNM) (34 articles, mainly concentrated in stroke, traumatic brain injury and spinal cord injury) and evidence-based education rehabilitation medicine (EBEDRM) (17 articles, mainly focuses on educational methodology), evidence-based nursing rehabilitation medicine (EBNRM) (2 articles), evidence-based engineering rehabilitation medicine (EBENRM) (7 articles), evidence-based traditional Chinese rehabilitation medicine (EBTCRM) (3 articles), evidence-based internal rehabilitation medicine (EBIRM) (11 articles), evidence-based intensive care rehabilitation medicine (EBICRM) (4 articles), evidence-based oncology rehabilitation medicine (EBORM) (6 articles), evidence-based physical therapy medicine (EBPTM) (3 articles), evidence-based cardiopulmonary rehabilitation medicine (EBCRM) (6 articles), evidence-based speech therapy medicine (EBSTM)/evidence-based occupation therapy medicine (EBOTM)/evidence-based geriatric rehabilitation medicine (EBGRM) (1 article). The EBMRM, EBNM and EBEDRM are relatively well developed. The development of EBNRM, EBENRM, EBTCRM, EBIRM, EBICRM, EBGRM, EBORM, EBCRM, EBPTM, EBSTM and EBOTM is relatively slow, indicating these eleven fields should be pay more attention in future.

The risk of corrosion failure of submarine pipeline increases sharply，and it is necessary to study the corrosion behavior and corrosion rate of submarine pipeline.In this work，18 groups of six factors and three-level orthogonal experiments were carried out for the submarine pipelines commonly used steel X65 steel in high temperature and high pressure reactors.The synergistic corrosion behavior of X65 steel by CO2，H2S，pH value，Cl-，temperatures and flow rates was studied，and the main controlling factors for corrosion were determined as CO2partial pressure ＞H2S partial pressure ＞Cl-concentration ＞pH value ＞flow rate ＞temperature.From the results of scanning electron microscope，the synergistic corrosion behavior of H2S，CO2and Cl-was clarified: CO2formed dense FeCO3，which was located at the bottom of the corrosion product film，and the surface was Fe sulfide.Moreover，Cl-passed through the corrosion product film to promote the occurrence of corrosion.Finally，based on the orthogonal experimental data，a six-factor corrosion rate prediction model was established，and the prediction model error was less than 20%.

The deuterium-tritium fusion reaction is the fastest commercially achievable artificially controlled fusion reaction. However, tritium, as a fuel and neutron radiation-activated material, poses radioactive safety challenges. To simulate the migration of tritium and radioactive dust in the environment under accident conditions, a dispersion simulation program called ACCTRI (ACCidental model for TRItium release) has been developed based on the modified Gaussian multi-puff model, considering dry and wet deposition and tritium re-emission effects. The concentration and dose results calculated using ACCTRI are very close to those calculated using UFOTRI and HotSpot, with a maximum difference of no more than one order of magnitude. A comparison with the experimental results reveals that the results of ACCTRI with tritium buoyancy correction are close to the experimental data. ACCTRI has good accuracy and can be used as a reference for environmental radioactivity safety in fusion reactor site selection and hypothetical accident analysis.

ABSTRACT China's socialized service industry of agricultural machinery emerged as the times required, which resolved the institutional contradiction between small farm households and large-scale agriculture. However, as cross-operation harvesters are still monitored based on phone calls, the monitoring efficiency and real-time performance are relatively poor. To improve the dynamic monitoring accuracy of harvester working areas, we proposed a working progress monitoring method based on harvester traveling trajectory and header status identification. The position and gap bridge angle information of harvesters was synchronously acquired in real-time. The height of the header above ground was calculated to determine whether the harvester was harvesting on a valid trajectory. Finally, the valid trajectory of the harvester was selected for area calculation. Field experiments showed that the header heights at the working and non-working tracing points collected by the system were discretely distributed at intervals of [0m, 0.5m] and (0.5m, 2m), respectively. The working progress monitoring algorithm proposed in this paper effectively improved the monitoring accuracy of harvester working areas. The mean error between the working areas calculated with identifying the header status and the actual cultivated land area in the five test plots was 0.09 hm2, with a mean error rate of 3.10%, 8.59% lower than that without identifying the harvester header status.

In order to study the sedimentation characteristics and action mechanism of cationic polyacrylamide (CPAM) with different ionic degrees on the high muddied coal slime water, the particle size composition and mineral composition of the high muddied coal slime water from Lijiahao Coal preparation Plant were studied. The influence of ionic degree of CPAM on sedimentation velocity, turbidity of clarification zone, thickness of compression zone and sedimentation kinetics of high muddied coal slime water was studied by using the experimental method of flocculation sedimentation of coal slime water. Zeta potential on the surface of slime particles was measured, and the effect of CPAM with different ionic degree on the zeta potential of slime particles was analyzed. The stability of coal slime water under different ionic conditions was studied by using Turbiscan Lab stability analyzer. Based on the sedimentation characteristics and dynamic stability of coal slime water, the sedimentation mechanism of CPAM ion degree on coal slime water was analyzed. The results show that large amount of kaolinite particles and high content of fine particles are the main reasons for the difficult settlement of coal slime water. Under the same dosage, CPAM has a poor sedimentation effect on coal slime water when the ionic degree is low. When the ionic degree is high, the sedimentation velocity of coal slime water is lower, the thickness of compression zone is higher, and the turbidity is lower. The sedimentation effect of coal slime water is good when the ionic degree is high, and CPAM with ionic degree 30%-60% has the best sedimentation effect when the dosage is 36 g/m3, with fast sedimentation speed, low turbidity and thin compression zone thickness. CPAM has great influence on the sedimentation effect and stability of coal slime water. CPAM can reduce the Zeta potential value on particle surface, promote the formation of flocs in the sedimentation process of slime water, accelerate the sedimentation speed, reduce the stability of slime water and turbidity after the sedimentation of coal slime water, due to its long chain containing positive active groups that can easily adsorb with the surface of negatively charged slime particles. The principle of action with coal slime water is “electric neutralization”, “adsorption bridge” and “net capture and sweep”. It is a kind of excellent coal slime water treatment agent.

When the gears work under high-speed and heavy-load conditions, the effects of friction and wear cannot be ignored. The gear modification can reduce gear wear and surface temperature, and has a significant effect on improving the anti-scuffing ability of gears. Thus, the heat distortion and modification of gears are studied. Based on the basic theories of gear meshing principle and gear modifying principle, the following studies have been made: a parametric model of gear thermo-mechanical coupling is established using the finite element simulation software; the steady-state heat balance equations for each face of the gear teeth are determined, and the finite element simulation software is used to automatically impose convection boundary conditions and frictional heat fluxes on each point of the gears. By solving the temperature field of the gear, the influence of gear tooth temperature change on gear deformation is analyzed, and gear modification technology is studied. The calculation formulas of elastic deformation, thermal deformation and thermo-mechanical coupling deformation are derived. The results show that the modification can reduce the gear temperature and improve the scuffing strength of the gear.

Deuterium （D） and tritium （T） have been regarded as the first-generation fuels for achieving commercial fusion energy. However， the utilization of the radionuclide tritium introduces concerns related to radioactive safety. This study sought to investigate methods for estimating airborne tritium sources following a fusion reactor incident. An algorithm that combines an adaptive Kalman filter with a deep feedforward neural network was developed to determine the tritium release height and rate. By utilizing observed data both pre- and post-filtering as inputs， the neural network's predictions for the tritium release rate were analyzed. The findings indicate that filtering significantly lowers the prediction errors. Considering a 20% monitoring error， the average relative error for the estimated release height is approximately 3% and that for the release rate is approximately 4%.

Commercial LiFePO4 (LFP) electrode still cannot meet the demand of high energy density lithium-ion batteries as a result of its low theoretical specific capacity (170 mA h g−1). Instead of traditional electrochemical inert polyvinylidene fluoride (PVDF), the incorporation of multifunctional polymeric binder becomes a possible strategy to overcome the bottleneck of LFP cathode. Herein, a novel polyimide (PI) binder was synthesized through a facile hydrothermal polymerization route. The PI binder exhibits better connection between active particles with uniform dispersion than that of PVDF. The multifunctional PI binder not only shows well dispersion stability in the organic electrolyte, but also contributes to extra capacity because of the existence of electrochemical active carbonyl groups in the polymer chain. Besides, the high intrinsic ion conductivity of PI also results in promoted ion transfer kinetic. Consequently, the LFP cathode using PI binder (LFP–PI) shows larger capacity and better rate capability than LFP cathode with PVDF binder (LFP–PVDF). Meanwhile, the superior binding ability also endows LFP–PI with great cycling stability compared to the LFP–PVDF electrode.

A pairwise coupling of 0D Super-P (SP), 1D carbon nanotubes (CNTs), and 2D graphene nanosheets (GNs) into binary carbon-based conductive additives was used here for the LiFePO4 cathode in lithium-ion batteries. For comparison, the LiFePO4 cathode with SP, CNT, or GN unitary conductive agent was also examined. Electrochemical test results suggest that the cathodes with binary conducting additives present greatly improved electrochemical performance than the traditional cathode system (only SP used). Especially, the LiFePO4 cathode containing 3% CNT component exhibits the highest specific capacity and the best cycling stability among all the cathodes with binary conducting additives, indicating that an appropriate amount of CNTs is critical in enhancing the conductivity and practical capacity output. However, an excess of CNTs leads to entangling with each other, hampering the uniform distribution of active materials and resulting in poor electrode performance. Furthermore, the combination of CNT and GN can effectively improve the capacity and cycling stability of the LiFePO4 cathodes due to the synergistic effect of 3D conductive networks constructed by the two.

Rice production is highly seasonal, and the timing for conducting harvest operations has a relatively significant impact on yields, especially the appropriate timing of the harvesting operations. Using scientific methods to monitor the appropriate harvest period can effectively reduce harvesting losses. Most of the existing studies in this field focus on yield changes that occur during the harvest period of rice and also use multispectral remote sensing for inversion of the crop canopy. However, there has been no research on combining the yields and spectral characteristics of the harvest period. In this article, a monitoring method for the appropriate harvest period of rice based on multispectral remote sensing was established. Remote sensing data of the rice canopy were acquired using UAV equipped with multispectral (550 nm, 660 nm, 735 nm, and 790 nm) cameras, and physiological characteristic data of rice moisture content, thousand-grain weight, and tassel ratios were determined simultaneously. Single-band and combined-band spectral reflectance were introduced as model input variables to compare the BP neural network, SVM, and decision tree; a quantitative inversion model of the physiological characteristics of rice was established. The accuracy of the inversion model with different input variables and model methods was evaluated, and the optimal inversion model for rice moisture content and thousand-grain weight was selected, which could be used to determine whether the crop was harvested during the appropriate period. The continuous monitoring of two rice varieties (South Japonica 46 and South Japonica 5055) indicated that the moisture content of South Japonica 46 decreased linearly during the 20-day trial period, while its thousand-grain weight showed a trend of increasing first and then decreasing. The moisture content of South Japonica 5055 showed a fluctuating downward trend, and its thousand-grain weight also showed a trend of increasing first and then decreasing. The spectral reflectance at 735 nm increased gradually, and that of both rice varieties increased from about 35% at the beginning of the trial to about 75% in the later stage. The spectral reflectance at the other three bands did not show significant change with the harvest date. The inverse model of spectral reflectance with rice thousand-grain weight and moisture content was established using the BP neural network, SVM, and decision tree. In single-band inversion models, the regression effect at 735 nm was relatively good in the BP neural network model, with the highest determination coefficients of spectral reflectance and thousand-grain weight of both rich varieties and the smallest RMSE of prediction results. In combined-band inversion models, the regression effects at 550 + 660+735 nm and 660 + 735+790 nm were the best in the SVM and thousand-grain weight inversion models.

With the development of the Internet, date of industry has gradually formed the trend of integration with the Internet, and the security problem is also prominent, which is mainly manifested in data collection, storage, transmission, application and other links, such as data disclosure and data being tampered with risk. This paper presents a method of security protection for large industrial data based on block chain technology. A unique ID is allocated to each machine in the factory, and all data of the ID are stored by IPFS technology, and the encrypted cipher text encrypted by the device ID and its data index is saved to the block chain to formed the only and untampered account book of the whole network. It ensures the security of data in all aspects.

In order to study the effect of the subsurface drain parameters on water-salt transport,this paper performs the field test in typical experimental area selected from Binhai New Area of Tianjin,China,calibrates and verifies the simulation effect of HYDRUS-2D by experimental data,and simulates the water-salt transport under different subsurface drain parameters by the validated model.The simulation results show that:HYDRUS-2D can well simulate water-salt transport of soil under the condition of subsurface drainage.When the depth of subsurface drains is kept unchanged,the larger the subsurface drains is spaced,the higher the water and salt are contained in the soil after leaching.When the spacing of subsurface drains is kept unchanged,the deeper the subsurface drains are,the lower the water and salt are contained in the soil after leaching.Among the 12 simulated subsurface drain scenarios,under the combined parameters of 140 cm depth (maximum) and 300 cm spacing (minimum),the salt of soil profile is 0.47~7.81 g/kg (minimum).Therefore,when the subsurface drain technology is applied to the improvement of saline-alkali soil,it is necessary to reduce the spacing of the subsurface drains or increase the depth of the subsurface drains to improve the leaching effect.

To solve the problem of artificial potential field algorithm(APF) being liable to fall into local minimum，this paper presents a strategy based on angle of rotating speed vectors to accurately locate the position of jump point.Combined with improved APF,the RRT based on transition of angle different of rotating speed vectors(TAS-RRT)can be used to path planning dynamicly. Firstly, artificial potential field algorithm is used in obstacle avoidance motion planning. When falling into local minimum,the sampling strategy of the basic RRT is improved to adaptively seek the target point and the connection mode of the local planner is adjusted to change exploration rate of the tree,so that the search process can be made to jump out of the attractive areas of local minimum point quickly.In addition, APF will be applied again when the the sampling point meets the stop condition of angle of rotating speed vectors. The simulation experiments show that the control precision and velocity of the motion planning are enhanced with TAS-RRT guiding the sampling nodes to the target one gradually and quickly.Besides that,the method can be applied to motion planning of different obstacle environment.

Researches on topological modification of polycarboxylate superplasticizers to improve the water-reducing or slump-retainning properties have been a hot topic in rencent years. Herein, a core crosslinked star polycarboxylate superplasticizers (SPCE) were synthesized by crosslinking the comb polycarboxylate superplasticizers (CPCE) in aqueous solution. Crosslinkers and spacing monomers were added into the polymerization to promote the formation of hydrophobic core. A larger molecular weight with 75% of yields of the SPCE were observed by gel permeation chromatography (GPC). The dispersing effect of SPCE on the cement paste was then investigated by varying the dosage of crosslinkers and spacing monomers. It was found that the dispersing ability of SPCE became weakened compared to the CPCE. More of the crosslinkers led to smaller flow spread, as revealed by cement paste experiments. Introduction of the spacing monomers contributed to the formation of SPCE. However, the dispersing ability was also weakened. Best conversion efficiency and water-reducing ability was obtained when the molar ratio of crosslinker and spacing monomer to CPCE was set as 3:5:1.