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AIM:To investigate the changes of retinal microcirculation after phacoemulsification and the influencing factors of visual acuity.METHODS: Retrospective analysis. A total of 264 cataract patients(264 eyes)who underwent phacoemulsification in our hospital from January 2022 to December 2022 were selected as the study objects. Patients were divided into < 0.3 group(66 eyes)and ≥0.3 group(198 eyes)according to the recovery of best corrected visual acuity(BCVA)at 3 mo after surgery. The changes of retinal microcirculation indexes were compared before and after treatment. Logistic regression and LASSO regression models were used to screen the influencing factors of postoperative BCVA. A nomogram prediction model of postoperative BCVA was constructed and verified. A restricted cubic spline Logistic regression model was established to analyze the dose-response relationship between end-diastolic velocity(EDV), peak systolic velocity(PSV)and the risk of BCVA recovery.RESULTS: At 3 mo postoperatively, EDV and PSV were significantly improved compared with those before treatment, and resistance index(RI)levels were significantly lower than those before treatment(all P0.05).CONCLUSION: After phacoemulsification, retinal microcirculation in cataract patients improved significantly. EDV, PSV, aqueous humor cell grade, fundus lesion grade, advanced age and Emery grade are all factors influencing poor BCVA recovery after cataract surgery.

The VSR-VSI dual three-phase pulse width modulation (PWM) converters based on the cascade connection of a front-end three-phase voltage source rectifier (VSR) and a back-end three-phase voltage source inverter (VSI) have been widely used in elevator energy feedback systems, but the front-end three-phase VSR using the traditional proportional integral (PI) double closed-loop control structure usually has the problem that the mid-end DC voltage cannot take into account the disturbance immunity and the follow-ability. Given this, an improved DC voltage regulation strategy of the three-phase PWM rectifier based on two-degree-of-freedom proportional integral differential (PID) is proposed. Firstly, the structure and working principle of the three-phase VSR-VSI dual three-phase PWM converters are expounded. Then, the PI double closed-loop control scheme of the front-end three-phase VSR and its parameter design process are given to analyze the reasons why this traditional scheme cannot have good disturbance immunity and follow-ability of the DC voltage regulation system. On this basis, an optimized DC voltage regulation improvement strategy for the front-end three-phase VSR based on two-degree-of-freedom PID and its corresponding parameter design method are given. Finally, the correctness and the superiority of the proposed three-phase PWM-VSR DC voltage regulation strategy are verified by using the simulation and experimental comparison results.

With the growing demand for transportation, there has been a significant increase in road-related projects, leading to potential risks in the safety of existing structures. This paper presents a study on the influence of new tunnel construction on the stability of an adjacent existing tunnel and provides valuable insights for the safety technology evaluation of similar tunnel crossing projects. In order to evaluate the influence of tunnel excavation on adjacent tunnels, the excavation process of a new tunnel near the original tunnel is simulated using the finite element software Midas GTS. This analysis includes the evaluation of static and dynamic responses. The results indicate that the horizontal and vertical displacements caused by the excavation of the railway tunnel are minimal. Furthermore, during the blasting excavation of the railway tunnel, the vibration velocity experienced by the highway tunnel remains below the safe allowable limit. These findings demonstrate that in this project, the influence of blasting excavation for the railway tunnel on the highway tunnel is both safe and manageable.

With the continuous increase of the spraying area, the problem of droplet drift risk in the spraying process of UAV is becoming increasingly prominent, especially the herbicide drift. In order to clarify the effect of the herbicide solution on the droplet size and the deposition and drift distribution characteristics sprayed by UAVs, the droplet sizes of 15 herbicide solutions sprayed by the centrifugal rotary atomizer nozzle installed in the plant protection UAV were measured in the laboratory, and the distribution of droplet deposition and drift in the spraying area and drift area were measured by adding a fluorescent tracer (60 g/hm2) to the tank in the field. The results showed that the herbicide solution had a significant effect on the droplet size distribution. The DV50 of all the other solutions was reduced after sprayed by the centrifugal atomizer except the Carfentrazone-ethyl water dispersible granule, and the maximum decrease ratio was 22.0%. The proportion of small droplets (V

A new method that combined image matching and shape from shading for terrain reconstruction was proposed to solve the lack of terrain in the landing area of Chang'e III. First, the reflection equation was established based on the Lommel– Seeliger reflection model. After edge extraction, the gradients of points on the edge were solved. The normal vectors of adjacent points were obtained using the smoothness constraint. Furthermore, the gradients of residual points in the image were determined through evolution. The inadequacy of the reflection equation was eliminated by considering the gradient as the constraint of the reflection equation. The normal vector of each point could be obtained by solving the reflection equation. The terrain without coordinate information was reconstructed by iterating the vector field. After using scaleinvariant feature transform to extract matching points in the descent images, the terrain was converted to a lander centroid coordinate system. Experiments were carried out with MATLAB-simulated images, laboratory images, and descent images of Chang'e III. Results show that the proposed method performs better than the classical SFS algorithm. The new method can provide reference for other deep space exploration activities.

Background: Although anti-HER2 therapies have been widely used against gastric carcinoma, the prognostic significance of HER2 overexpression remains unclear. Previous studies failed to provide convincible evidence due to inconsistent HER2 evaluation criteria and heterogeneous clinical characteristics. Objectives: To figure out the prognostic significance of HER2 expression in gastric cancer, we rigorously designed and conducted this study. Design: Meta-analysis. Data sources and methods: Record retrieval was performed by searching PubMed, Web of Science, Cochrane Library, Embase, ASCO, and ESMO meeting libraries from inception to November 2022. Cohort studies investigating overall survival comparison between HER2-positive and HER2-negative gastric cancer patients were included. Both resectable and advanced cases were separately collected while HER2 evaluation standards should be consistent across eligible studies. Newcastle–Ottawa Scale was used for quality assessment. Overall survival was the only endpoint and effect size was presented by hazard ratio (HR) with its 95% confidence interval. The pooled calculation was conducted on Review Manager 5.4. Results: Thirty studies were eligible, including 9945 patients. Eligible studies were mostly high quality (n = 31). Regarding resectable cases (n = 22), HER2-positive groups had significantly worse prognosis than HER2-negative counterparts (HR 1.56, 95%CI 1.32–1.85, p < 0.00001). For HER2-positive patients with advanced gastric cancer (n = 10), HER2 overexpression was also an unfavorable survival indicator (HR 1.70, 95%CI 1.23–2.35, p = 0.001). Potential heterogeneous studies had been eliminated while outcomes remained stable by sensitivity analysis. Subgroup analysis suggested HER2-positive patients had a poorer prognosis in both East Asian (resectable: HR 1.56; advanced: HR 1.32) and non-East Asian countries (HR 1.58; HR 3.27). Conclusion: As a novel survival biomarker in gastric cancer, HER2 overexpression indicates unfavorable prognosis among both resectable and advanced patients, irrespective of East Asian or non-East Asian populations. Trial registration: PROSPERO (CRD42020168051). [ABSTRACT FROM AUTHOR]

BACKGROUND: Effective utilization of plant protection UAVs in peanut cultivation management necessitates a comprehensive grasp of how application volume rates and pesticides influence peanut leaf spot and rust control. This study aimed to compare the effects of application volume rates and pesticides on droplet deposition, disease, leaf retention rate and peanut yield. A T20 plant protection unmanned aerial vehicle (UAV) sprayer was used to apply four various pesticide doses. In comparison, a knapsack sprayer was used to spray with an application volume rate of 450 L ha−1. RESULTS: The results showed a significant difference in droplet deposition between the plant protection UAVs and the electric knapsack sprayer. In the pesticide treatment with an application volume rate of 15.0 L ha−1, there was no significant difference in the deposition on the peanut canopy of each pesticide treatment, but there was a significant difference in the deposition on the ground in the treatment with adding vegetable oil adjuvant. The treatment with added vegetable oil additives showed the worst performance. The treatment with an application volume rate of 22.5 L ha−1 showed the best performance, with the leaf spot control effect being only 0.3% lower than that of the electric knapsack sprayer. CONCLUSION: Plant protection UAV spraying is feasible to control peanut diseases. Considering the operational effectiveness of the plant protection UAV and application volume rate, it is recommended to use an application volume rate of 22.5 L ha−1 without adding vegetable oil adjuvants for field operations. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Cubic silicon carbide (3C‐SiC) has superior mobility and thermal conduction over that of widely applied hexagonal 4H‐SiC. Moreover, much lower concentration of interfacial traps between insulating oxide gate and 3C‐SiC helps fabricate reliable and long‐life devices like metal‐oxide‐semiconductor field effect transistors. However, the growth of high‐quality and wafer‐scale 3C‐SiC crystals has remained a big challenge up to now despite decades‐long efforts by researchers because of its easy transformation into other polytypes during growth, limiting the development of 3C‐SiC‐based devices. Herein, we report that 3C‐SiC can be made thermodynamically favored from nucleation to growth on a 4H‐SiC substrate by top‐seeded solution growth technique, beyond what is expected by classical nucleation theory. This enables the steady growth of high‐quality and large‐size 3C‐SiC crystals (2–4‐inch in diameter and 4.0–10.0 mm in thickness) sustainable. The as‐grown 3C‐SiC crystals are free of other polytypes and have high‐crystalline quality. Our findings broaden the mechanism of hetero‐seed crystal growth and provide a feasible route to mass production of 3C‐SiC crystals, offering new opportunities to develop power electronic devices potentially with better performances than those based on 4H‐SiC. [ABSTRACT FROM AUTHOR]