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AIM: To investigate the abnormal conditions and change patterns of accommodative facility in patients with different refractive states before and after small incision lenticule extraction(SMILE)surgery.METHODS:A prospective clinical cohort study was conducted. A total of 59 patients(118 eyes)who underwent SMILE surgery and had visual function files established in our hospital from June to December 2023 were randomly selected, including 37 males and 22 females, aged 18-35 years(with an average age of 25.19±5.65 years). According to the preoperative spherical equivalent(SE), they were divided into two groups: the low-to-moderate myopia group(SE≥-6.00 DS)with 40 patients(80 eyes), and the high myopia group(SE0.017).CONCLUSION: After SMILE surgery, the monocular accommodative facility shows a transient decrease and then exceeds the preoperative level at 1 mo after surgery, and the binocular accommodative facility gradually improves after surgery. SMILE surgery has a positive impact on the monocular and binocular accommodative facility in patients with low-to-moderate myopia, but has no significant impact on the accommodative facility in patients with high myopia. It is of clinical significance to strengthen the detection of monocular and binocular accommodative facility before and after SMILE surgery.

Reconfigurable intelligent surface (RIS) effectively improves the performance of 6G communication systems by intelligently controlling the electromagnetic propagation path. However, the integration of a large number of reflecting elements in RIS increases the complexity of multi-beam control and enlarges the codebook search space, leading to insufficient real-time control capabilities and difficulties in multi-user beam tracking. To enhance the applicability of RIS in multi-user mobile scenarios, an innovative inverse diffraction-based field source iterative model was proposed to rapidly generate near- and far-field multi-user control codebooks. A RIS-assisted single base station positioning scheme was designed to sense the movement of users and switch beams in real-time. A prototype of a RIS-assisted multi-user beam tracking system was developed, enabling fast beam alignment during multi-user mobility. Experimental results show that millisecond-level beam switching can achieve real-time information transmission for mobile multi-users.

The application of Internet of Things (IoT) technology has become more and more widespread, and the smart home based on IoT technology has penetrated thousands of households and the design of the internal environment of the building is also gradually intelligentized and digitized. This study realizes the personalized and humanized design of IoT technology in the internal environment of buildings through the design of a personalized smart home system based on IoT, which focuses on the use of the Apriori algorithm to mine the association rules of the user’s preferences for the internal environment of the building. Then, it uses the GA-BP neural network algorithm to predict the audience’s preferences and the PMV indexes so as to achieve the personalized and humanized design of the smart home system. And human-centered design. The system is evaluated for its performance and practical application, and the design effect of the building’s interior environment is examined. The network bandwidth bottleneck of the system is 2M, and the absolute error of the GA-BP prediction model is within (−0.04, 0.19), with an average accuracy of 99.245% and an improvement of 20.38% over the BP prediction model. The importance and satisfaction of all the scenario models of this system are within (3,5), the scenario model settings are more reasonable, the user satisfaction is high, and it can meet the user’s personalized and humanized needs. The results of this research can guide the personalized and humanized design of the internal environment of the building and provide certain theoretical references for the systematic study of the design of the internal environment of the building.

Because the communication link connection in the Internet of Vehicles is transient and intermittent, the established connection may be disconnected at any time, which cannot meet the requirements of the data transmission of the Internet of Vehicles. Therefore, based on the traditional data transmission mechanism, the fuzzy comprehensive evaluation method is used to achieve the optimal design of the data transmission mechanism of the Internet of Vehicles. First, according to the operation mechanism of the Internet of Vehicles build the Internet of Vehicles model. Then in this model, the fuzzy comprehensive evaluation is used to analyze the data transmission characteristics of the Internet of Vehicles, and the characteristics evaluation results of data transmission are obtained. Finally, set the data transmission protocol of the Internet of Vehicles, select the appropriate data transmission path, allocate the data transmission load, and realize the data transmission of the Internet of Vehicles. The experimental results show that compared with the traditional data transmission mechanism of the Internet of Vehicles, the speed of the designed transmission mechanism is increased by 3.58 MB/s, and the packet loss rate is reduced by 41%.

Abstract Background Prognostic indicators based on the initial prostate‐specific antigen (PSA) levels, nadir PSA, and time to PSA nadir were calculated to evaluate prognosis after primary androgen deprivation therapy (PADT), as these have been reported in very few studies. We attempted to evaluate the prognostic role of the slope associated with nadir PSA in patients treated with PADT. Methods A total of 107 patients who were treated with PADT from 2015 to 2019 were reviewed. The Kaplan–Meier method and Cox regression model were used to analyze the prognostic significance of the slope associated with nadir PSA in predicting progression‐free survival (PFS) and overall survival (OS). Results After PADT, the median follow‐up duration was 40.1 months; 66 patients (61.7%) had disease progression, and 33 patients (30.8%) died. In the univariate analysis, T stage, N stage, nadir PSA, time to PSA nadir, nadir PSA declining slope (nPSA‐DS), nadir PSA percentage declining slope (nPSA‐PDS), and nadir PSA line slope (nPSA‐LS) were significant predictors for PFS and OS. The multivariate analysis showed that a higher nPSA‐DS (> − 0.74) and lower PSA nadir (≤0.16 ng/ml) were independent predictors for prolonged survival. The significance of nPSA‐DS and nPSA was supported by the analysis of nPSA‐DS and nPSA as time‐dependent covariates. The combined analyses demonstrated that patients with a higher nPSA‐DS and lower PSA nadir had the best PFS and OS. Conclusions The slope associated with the nadir PSA of nPSA‐DS was a significant independent predictor for patients treated with PADT. Nadir PSA and nPSA‐DS have a synergistic effect on prognosis.

Aiming at the problems of eccentric wear and poor sealing performance of conventional gas well plungers in directional wells, a CFD-based optimized design has been adopted for the key structures of the rotary dynamic seal plunger, and a mathematical model of liquid discharge of rotary dynamic seal plunger has been established. The working mechanism of key structures like spiral groove and jet hole on the plunger has been clarified. The parameters of the spiral grooves have been optimized, with the spiral angle of 30°, the groove width of 6mm, and the groove number of 8; and the number of injection holes has been optimized at 12 through orthogonal experimental design. The results of laboratory verification experiments show that the optimized plunger structure successfully realizes the rotating liquid discharge, with the deviation between running and rotation speed of the plunger and the numerically simulated speed below 10%. Based on the indoor experimental research and field application, it can be concluded that the theoretical analysis method can accurately characterize the liquid drainage mechanism of the rotary dynamic seal plunger. The optimized rotary dynamic seal plunger is suitable for the gas well dewatering process of inclined wells with an inclination angle of less than 60°.

Neural network modeling for nonlinear time series predicts modeling speed and computational complexity. An improved method for dynamic modeling and prediction of neural networks is proposed. Simulations of the nonlinear time series are performed, and the idea and theory of optimizing the initial weights and threshold of the GA algorithm are discussed in detail. It has been proved that the use of GA-BP neural network in cigarette sales forecast is 80% higher than before, and this method has higher accuracy and accuracy than the gray system method.

The comprehensive performance of suspension directly affects the handling stability and riding comfort of the vehicle. The suspension performance of a domestic vehicle was verified. By using ADAMS/car software, the front suspension model with flexible stabilizer bar subsystem and the rear suspension model with flexible torsion beam subsystem are established to form the suspension system of vehicle with rigid-flexible coupling model. The displacement and force were applied to the suspension system respectively. The dynamic and elastic kinematics analysis were carried out, and the wheel alignment parameters under different characteristics were obtained. The simulation results show that the simulation values were basically consistent with the real vehicle K＆C test data. The comprehensive performance of the suspension of this model was more optimized than that of the standard model. At the same time, through the rolling acceleration, understeering and car rolling three aspects, the steady-state rotary road test was conducted to further verify that the steady-state characteristics of the vehicle meet the design requirements and have good motion characteristics.

Background and PurposeThis study aimed to investigate the arterial disease risk factors for the progression of intraplaque hemorrhage (IPH) in patients with carotid atherosclerosis using serial high-resolution magnetic resonance (MR) imaging.MethodsConsecutive symptomatic patients who had MRI evidence of intraplaque hemorrhage present in the ipsilateral carotid artery with respect to the side of the brain affected by stroke or TIA were recruited in the study. All the patients underwent follow-up MR imaging at least 6 months after baseline. The annual change in IPH and other carotid plaque morphology was calculated, and a tertile method was used to classify the plaques as progressed or not with respect to IPH volume using the software CASCADE. Logistic regression and receiver operating characteristic (ROC) curve were conducted to evaluate the risk factors for the progression of IPH.ResultsA total of thirty-four symptomatic patients (mean age: 67.1 years, standard deviation [SD]: 9.8 years, 27 men) were eligible for the final analysis, and contralateral plaques containing IPH were seen in 11 of these patients (making 45 plaques with IPH in total). During mean 16.6-month (SD: 11.0 months) follow-up, the overall annual change in IPH volume in 45 plaques with IPH was mean −10.9 mm3 (SD: 49.1 mm3). Carotid plaques were significantly more likely to be classified in progressed IPH group if the patient was taking antiplatelet agent at baseline (OR: 9.76; 95%CI: 1.05 to 90.56; p = 0.045), had a baseline history of current or past smoking (OR: 9.28; 95%CI: 1.26 to 68.31; p = 0.029), or had a larger baseline carotid plaque-containing vessel wall volume (OR: 1.36 per 10 mm3; 95%CI: 1.02 to 1.81; p = 0.032) after adjustments for confounding factors. ROC analysis indicated that the combination of these three risk factors in the final model produced good discriminatory value for the progressed IPH group (area under the curve: 0.887).ConclusionsTaking an antiplatelet agent at baseline, a baseline history of current or past smoking and larger baseline carotid plaque-containing vessel wall volume were independently predictive of plaques being in the progressed IPH group. Our findings indicate that awareness and management of such risk factors may reduce the risk of intraplaque hemorrhage progression.

The output shaft is one of the core components of the gearbox of an oil rig,The reliability of the output shaft directly affects the service life and economic benefit of the oil rig. In this paper,the stress analysis of the structure of the original output shaft is carried out by using the finite element method; The optimization and improvement scheme is put forward,and the stress of the output spindle before and after the improvement is compared and analyzed,According to the analysis results,the final improvement scheme of the output shaft is determined,The results show that the safety factor of the improved output shaft is significantly improved,The modal of the output shaft is analyzed by finite element method,It is verified that the working speed of the output shaft is within the safe range. The research in this paper has certain guiding significance to improve the performance of oil rig output shaft.

Proteolysis, including post-translational proteolytic processing as well as protein degradation and amino acid recycling, is an essential component of the growth and development of living organisms. In this article, experts in plant proteolysis pose and discuss compelling open questions in their areas of research. Topics covered include the role of proteolysis in the cell cycle, DNA damage response, mitochondrial function, the generation of N-terminal signals (degrons) that mark many proteins for degradation (N-terminal acetylation, the Arg/N-degron pathway, and the chloroplast N-degron pathway), developmental and metabolic signaling (photomorphogenesis, abscisic acid and strigolactone signaling, sugar metabolism, and postharvest regulation), plant responses to environmental signals (endoplasmic-reticulum-associated degradation, chloroplast-associated degradation, drought tolerance, and the growth-defense trade-off), and the functional diversification of peptidases. We hope these thought-provoking discussions help to stimulate further research.

In order to find out the cause of the fracture of the cutting spindle as one of the key components of a cantilever roadheader, and to solve this fracture problem, this paper analyzes it in multiple ways and proposes an improved scheme. Through the analysis of fracture surface macro-morphology, material chemical composition, mechanical properties, microstructure and finite element stress of the cutting spindle, the failure conclusion is drawn and the corresponding improvement scheme is put forward. The results show that the cutting spindle in the actual complex working conditions, due to machining and heat treatment in the process of shortcomings, as well as the use of abnormal operation, resulting in the operation of the stress concentration in the greater position of fracture failure. According to the failure reasons, the corresponding improvement schemes are put forward: by optimizing the structure and improving the processing, reducing the stress concentration, improving the heat treatment process, improving its mechanical properties and other methods to improve the performance of the shaft to meet its functional requirements. The results of this study can provide a good reference value in solving the problem of failure of shaft transmission parts and improving the performance of shaft transmission parts.

This paper proposed an analysis scheme for the multiple fracture failure of the gear rotor of the melt pump used in the key equipment of a chemical plant.Through the analysis of damage fracture analysis,material property analysis,microstructure analysis and strength checking,the root causes of failure were found,the conclusion of failure was concluded and the improvement scheme was proposed.The analysis results show that the gear rotor of molten pump has some defects in the process of design and machining under complicated conditions,which leads to its frequent failure during operation.By changing its structure,reducing stress concentration,the selection of good materials,improve production processes and other ways to effectively improve the performance of the shaft to meet their functional needs.The results of this research could provide certain reference value in improving the service performance of key transmission parts,especially gear type transmission shafts.

In view of problems of complex structure of main circuit and limited power and voltage existed in traditional traction system of AC-DC-AC electric locomotive, a traction converter for electric locomotive with single-phase AC input and three-phase AC output was designed based on structure of modular multilevel converter using full bridge sub-module. The traction converter can drive traction motor directly, so as to eliminate vehicle-mounted step-down transformer and reduce complexity of traction system of electric locomotive. A constant AC voltage control strategy in outer loop and direct current control strategy in inner loop was proposed according to mathematic model of the converter established in two-phase synchronous rotating dq coordinate system. The simulation results verify validity of the converter and the control strategies.

The wheel gearbox is a key component of Multi-axis super-heavy hybrid test platform,for the special nature of the application,on the one hand to meet the requirements of vehicle wheel power transmission requirements,while also meet lightweight and high reliability requirements.Therefore,in the wheel gearbox design,taking the lightweight for the wheel gearbox as the target,reliability as constraints,the optimization design scheme of the wheel gearbox is proposed.After the high- speed test,full load fatigue test and overload fatigue test verification,the wheel gearbox performance and reliability meet the requirements of super- heavy hybrid multi- axis test platform.

This paper focuses on thermal stability of molten salts, operating temperature range and latent heat of molten salts at a high temperature. In this experiment, multi-component molten salts (purified Solar Salt) composed of purified NaNO3 and purified KNO3 were prepared by statical mixing method. Compared with unpurified Solar Salt, purified Solar Salt had a higher thermal stability. The optimal temperature would be increased from 500°C to 550°C, and the upper limitation temperature increases from 577.5°C to 593.7°C. Meanwhile, thermal stability and thermal cycling analysis showed the purified Solar Salt had a lower melting point and the deterioration time of molten salts was reduced. The melting point of purified Solar Salt decreases sharply to 223.8°C and the latent heat increases from 74.39 J/g to 80.79 J/g. Besides, the XRD and chemical analysis test indicated that the degree of degradation reduced and the thermal storage efficiency of purified Solar Salt was improved.

Malware is one of the most serious network security threats. To detect unknown variants of malware, many researches have proposed various methods of malware detection based on machine learning in recent years. However, modern malware is often protected by software packers, obfuscation, and other technologies, which bring challenges to malware analysis and detection. In this paper, we propose a system call based malware detection technology. By comparing malware and benign software in a sandbox environment, a sensitive system call context is extracted based on information gain, which reduces obfuscation caused by a normal system call. By using the deep belief network, we train a malware detection model with sensitive system call context to improve the detection accuracy.

Direct sequence spread spectrum (DSSS) signal uses phase coherent signals where the information symbols are multiplied with a code sequence, commonly known as chips. The signals are processed at the receiver using the code sequence as a matched filter to extract the information symbols. Taking advantage of the spread processing gain derived from the matched filter, communications can be carried out at low signal levels, which is the preferred method for high quality underwater acoustic (UWA) communication and remote UWA communication. However, in practical applications, DSSS UWA communication will face lots of interferences including multipath interference, Doppler compression interference and phase fluctuation interference, which will seriously affect the performance of DSSS. This paper first analyzes the interferences that DSSS faces in practical applications based on multiple actual received data collected in different water areas. By calculating the gain of the matched filter loss, one can find that influence of phase fluctuation interference has the most serious impact on DSSS. Secondly, the corresponding receiver processing algorithms are given for these interferences, including the differential energy detector and Doppler estimation method. The performance of differential energy detector under the above interferences is analyzed, which shows that the differential energy detector is insensitive to slow phase fluctuation interference and multipath interference and the differential energy detector combined with Doppler compensation can work well based on moving at-sea data. Finally, the parameter design of DSSS system in practical application is discussed and parameter design of DSSS UWA communication system should comprehensively consider the Doppler compression interference and phase fluctuation interference.

The circadian oscillator allows organisms to synchronize their cellular and physiological activities with diurnal environmental changes. In plants, the circadian clock is primarily composed of multiple transcriptional-translational feedback loops. Regulators of post-transcriptional events, such as precursor messenger RNAs (pre-mRNA) splicing factors, are also involved in controlling the pace of the clock. However, in most cases the underlying mechanisms remain unclear. We have previously identified XAP5 CIRCADIAN TIMEKEEPER (XCT) as an Arabidopsis thaliana circadian clock regulator with uncharacterized molecular functions. Here, we report that XCT physically interacts with components of the spliceosome, including members of the Nineteen Complex (NTC). PacBio Iso-Seq data show that xct mutants have transcriptome-wide pre-mRNA splicing defects, predominantly aberrant 3' splice site selection. Expression of a genomic copy of XCT fully rescues those splicing defects, demonstrating that functional XCT is important for splicing. Dawn-expressed genes are significantly enriched among those aberrantly spliced in xct mutants, suggesting that the splicing activity of XCT may be circadian regulated. Furthermore, we show that loss-of-function mutations in PRP19A or PRP19B, 2 homologous core NTC components, suppress the short circadian period phenotype of xct-2. However, we do not see rescue of the splicing defects of core clock genes in prp19 xct mutants. Therefore, our results suggest that XCT may regulate splicing and the clock function through genetically separable pathways.