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• A leak rate prediction model is proposed for hatch seals, facilitating the assessment of various parameters' effects. • The model is validated through comprehensive leakage tests on hatch seals with various structural parameters. • Parametric studies are performed to determine parameter sensitivity under different levels of pressure. • Response surface analysis is performed to guide the optimization of hatch seals under different operating pressures. The aim of this study is to establish a multi-parameter leakage rate prediction model for the sealing structure of large diameter hatches, enabling direct enhancements the hatch's sealing structure. The model integrates mesoscopic interfacial flow simulations and macroscopic structural deformation simulations to facilitate comprehensive analyses. This approach allows for quantitative assessment of various parameters influencing the leakage rate, including sealing surface morphology, material properties, structural dimensions, and operating environment. A leakage rate test was conducted in which several parameters were adjustable, validating the proposed model's accuracy through close agreement between experimental measurements and theoretical predictions. The effects of four parameters were examined: bolt preload force F n , cover flange thickness t c , gasket thickness t g , and gasket inner diameter D i,g. The leakage rate was found to be the most sensitive parameter to changes in F n when compared to t c , t g , and D i,g. The effects of t c , t g , and D i,g grew more prominent only at pressures exceeding 1.0 MPa. With leakage rate as the response quantity, response surface analysis was implemented to clarify the interaction between the four parameters. The results indicated that the optimal solutions for two cases with design pressures of 0.66 MPa and 2.0 MPa were essentially similar; differences were observed in their respective worst-case scenarios. Under high pressure and medium-level preloading, hatches should be designed to avoid cases wherein two or three structural parameters simultaneously reach lower levels. [ABSTRACT FROM AUTHOR]

• Combining SWE, UTD and the reaction theorem enables accurate calculation of mutual coupling between two antennas on a platform. • SWE is utilized to compute the direct electromagnetic field, followed by UTD for platform scattering field computation, and mutual coupling is evaluated through a reaction integral. • Numerical examples demonstrate superior speed and accuracy compared to MLFMA and MoM-UTD methods. • Offers an efficient and accurate mutual coupling evaluation method suitable for complex platform structures. For mutual coupling evaluation between antennas on the platform, present an enhanced algorithm that combines the spherical wave expansion (SWE), the uniform theory of diffraction (UTD), and the reaction theorem to accurately calculate the mutual coupling between two antennas mounted on a platform. The algorithm begins by employing SWE to compute the direct electromagnetic field radiated by the antennas. Subsequently, UTD is introduced to capture the field scattered by the platform. Finally, the mutual coupling is evaluated through the reaction integral. Numerical examples highlight the algorithm's promising speed and accuracy, surpassing the performance of the MLFMA and MoM-UTD methods. With a computational complexity of O (LMN 3) , our approach offers significant improvements for mutual coupling analysis in platform-based antenna systems. [ABSTRACT FROM AUTHOR]

As the main objective influencing factor on the brake safety of autonomous vehicles, pavement texture information is directly related to road surface antiskid performance. However, in the brake system of autonomous vehicles, the influence of road surface adhesion characteristics on braking stability is seldomly considered. To study the braking stability of autonomous vehicles on curved sections under different road conditions, the advanced close-range photogrammetry system was utilized to extract the road surface texture information. Thereafter, the power spectral density (PSD) of the road surface was calculated by MATLAB to obtain the pavement adhesion coefficient curves based on the Persson friction theory model under different road conditions. Considering the pavement adhesion characteristics, the braking model of autonomous vehicles was built in Simulink, and then, the braking performance on curved sections was analyzed with CarSim/Simulink cosimulation. The results indicate that, according to the adhesion coefficient of different asphalt pavement types under different road conditions, the ranking order is open-grade friction course (OGFC) > stone matrix asphalt (SMA) > dense-graded asphalt concrete (AC). In addition, both the maximum lateral offset distances and the maximum lateral forces of the tires decrease as the curve radius gradually increases under different road conditions. It can also be found that there is a relatively uniform vertical forces distribution of the tire when the curve radius is no less than 100 m, and the limit speed of the vehicle varies parabolically with increasing in curve radius. Compared with dry road, the reduction of vehicle braking deceleration is more significant and the yaw rate is greater on wet road. Last but not least, the braking comfort with a radius of 200 m is the best according to the comfort index (CI) in International Standard ISO, in which the comfort level can be sorted into six levels. [ABSTRACT FROM AUTHOR]

The discrete element software PFC3D was applied to establish a virtual rutting test for PAC-13 porous asphalt pavement and the rutting resistance of porous asphalt pavement was studied. The image processing technology and 3D modeling technology were used to establish a 3D aggregate model library, and the PAC-13 asphalt mixture was simulated. The reliability of the method was verified by comparing the virtual rutting test with the indoor rutting test. In addition, the influence of aggregate gradation and environmental temperature on the rutting resistance of porous asphalt mixture was discussed. The stress response of the pavement structure under the braking load was analyzed, the curve of the internal stress of the pavement structure with the depth under the braking load was obtained, and the position of the maximum deformation was predicted. The influence of aggregate gradation on the deformation of the specimen plate under the braking force was discussed. The results show that the simulation results of the virtual model established by PFC3D fit well with the indoor test, and can simulate the rutting test of the porous asphalt mixture. Coarse aggregate gradation has a significant effect on the anti-rutting performance of porous asphalt mixtures. The effect of temperature on the anti-rutting performance of asphalt mixtures is closely related to the softening point of asphalt. With the increase of acceleration, the road surface will move forward along the direction of travel, and the displacement will gradually increase; while the displacement in the vertical direction will decrease significantly with the increase of acceleration. [ABSTRACT FROM AUTHOR]

The modulus of asphalt pavement material is a necessary parameter for the design, strength measuring and stability evaluation of asphalt pavement. To get more precise test data for asphalt pavement material modulus, a new modulus back calculation method is proposed in this article, named as the Firefly Asphalt Back Calculation Method (FABCM). This novel method uses the firefly optimization algorithm, which is a kind of particle swarm intelligence algorithm imitating the information transfer process among fireflies. To demonstrate the reliability and stability of FABCM, and to study the feasibility of multi-parameter modulus back calculation methods, this article used theoretical deflection curves calculated by BISAR3.0 and the actual measurement data of deflection curves and vertical pressures on the subgrade top surfaces on the full-scale test circular track in the Research Institute of Highway, Ministry of Transport (RIOHTrack) to conduct a modulus back calculation. The results show that FABCM only takes 0.5–1 s for each calculation, and the back calculation errors in the verification of FABCM are mostly smaller than 1%, which means that the firefly optimization algorithm was modified effectively in this article. Moreover, this article also indicates some key factors influencing the accuracy of modulus back calculation, and several reasonable suggestions to the application of modulus back calculation. [ABSTRACT FROM AUTHOR]

In this work, the impact of nitrogen doping (N-doping) on the distribution of sub-gap states in amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) is qualitatively analyzed by technology computer-aided design (TCAD) simulation. According to the experimental characteristics, the numerical simulation results reveal that the interface trap states, bulk tail states, and deep-level sub-gap defect states originating from oxygen-vacancy- (Vo) related defects can be suppressed by an appropriate amount of N dopant. Correspondingly, the electrical properties and reliability of the a-IGZO TFTs are dramatically enhanced. In contrast, it is observed that the interfacial and deep-level sub-gap defects are increased when the a-IGZO TFT is doped with excess nitrogen, which results in the degeneration of the device's performance and reliability. Moreover, it is found that tail-distributed acceptor-like N-related defects have been induced by excess N-doping, which is supported by the additional subthreshold slope degradation in the a-IGZO TFT. [ABSTRACT FROM AUTHOR]

Summary: Carbon corrosion in the catalyst is an important factor limiting the lifetime of proton exchange membrane fuel cells (PEMFCs). The water distribution inside the PEMFC directly determines the carbon support's corrosion rate in the catalyst. This study first investigates the water mole fraction distribution in the catalyst under different operating conditions, such as relative humidity (RH), temperature, pressure. It then divides the catalyst into different flooded areas according to the relationship between the water vapor partial pressure and saturated vapor pressure. Finally, it investigates the carbon corrosion characteristic of each region. The carbon corrosion of the catalyst is mainly divided into the corrosion in the non‐flooded area and the corrosion in the flooded area. The results show that the decay rate of carbon support is around 4% after 5000 hours of operation in the non‐flooding area. However, the degradation of the carbon support in the flooded area after 100 hours is as high as around 97.76%. Therefore, how to avoid flooding is the important issue that needs to be considered in the PEMFC. Moreover, increasing the pressure and RH promote the carbon corrosion in both cases, while increasing the temperature increases the carbon corrosion reaction rate, but it is beneficial to alleviate water flooding. Highlights: Water distribution and carbon corrosion under different working conditions.Divide the catalyst into varying levels of flooded areas.The carbon corrosion degree in the flooded area is as high as 97.76% after 100 hours.Increasing temperature increases the corrosion rate, but alleviates water flooding. [ABSTRACT FROM AUTHOR]

Retinoblastoma (RB) is the most common intraocular malignancy in children. It has been previously reported that p38 MAPK is related to the pathogenesis of RB. Here we aim at investigating how p38 MAPK affected RB progression through mediating USP22/SIRT1/SOST axis. In this study, Thirty-two cases of RB and normal retinal tissues were collected. The expression of p38 MAPK, phosphorylation of p38 MAPK (P-p38 MAPK), USP22, SIRT1 and SOST in clinical tissues and cells was measured using RT-qPCR, IHC assay or western blot analysis. Cell proliferation was detected by CCK-8. Apoptosis rate of cells was examined by flow cytometry. Cell migration was evaluated using scratch test. Cell invasion ability was examined by Transwell assay. Co-immunoprecipitation (CO-IP) was utilized to measure the deubiquitination of USP22 on SIRT1. In vivo , mice were respectively injected with plasmids and the tumor growth as well as the tumor weight were detected. Results showed that p38 MAPK, P-p38 MAPK and SOST were poorly expressed in RB tissues and cells whereas USP22 and SIRT1 were overly expressed. P-p38 MAPK inhibited the expression of USP22, and overexpression of USP22 eliminated the inhibitory roles of P-p38 MAPK on tumor growth, as well as cell proliferation, migration and invasion. USP22 stabilized and promoted the expression of SIRT1 through its deubiquitination function. Silencing the expression of SIRT1 contributed to boosted expression of SOST, thus suppressing the growth of tumor cells. Collectively, the phosphorylation of p38 MAPK regulates the SIRT1/SOST axis to protect against RB via silencing USP22. The findings present some cues for a further approach to RB. [ABSTRACT FROM AUTHOR]

Chemoresistance remains the primary obstacle threatening the prognosis of retinoblastoma (RB). microRNAs (miRNAs) are acknowledged as critical regulators of drug resistance. This study explored the molecular mechanism of miR-130a-3p affecting the chemosensitivity of RB to vincristine (VCR). miR-130a-3p expression of human retinal astrocytes and RB cell lines (Y79, WERI-Rb-1, SO-Rb50, and SO-Rb70) was detected using RT-qPCR. VCR-resistant RB cell line Y79/VCR was induced. miR-130a-3p expression of Y79/VCR cell line and its corresponding parental cell line was detected. Y79/VCR cells were subjected to miR-130a-3p overexpression treatment. The cell proliferation was measured using MTT assay, and the IC50 value and drug resistance index were examined using CCK-8 assay. The targeting relationship between miR-130a-3p and PAX6 was predicted through bioinformatics analysis and verified using dual-luciferase assay. Functional rescue experiments were conducted to confirm the role of PAX6 in chemosensitivity of RB cells. The effect of miR-130a-3p on tumorigenesis and VCR sensitivity was observed in vivo. miR-130a-3p was downregulated in VCR-resistant RB cells. Overexpression of miR-130a-3p repressed the proliferation of Y79/VCR cells and enhanced chemosensitivity. miR-130a-3p targeted PAX6 expression. Overexpression of PAX6 reversed the effect of miR-130a-3p on chemosensitivity of Y79/VCR cells. Overexpression of miR-130a-3p suppressed tumor growth and reduced VCR resistance in vivo. miR-130a-3p enhanced the chemosensitivity of Y79 RB cells to VCR by targeting PAX6 expression. [ABSTRACT FROM AUTHOR]

Objective: To establish a dynamic nomogram based on preoperative clinical data for prediction of lateral lymph node metastasis (LLNM) of papillary thyroid carcinoma. Study Design: Retrospective study. Setting: The Sixth Affiliated Hospital of Sun Yat-Sen University. Methods: The data of 477 patients from 2 centers formed the training group and validation group and were retrospectively reviewed. Preoperative clinical factors influencing LLNM were identified by univariable and multivariable analysis and were to construct a predictive dynamic nomogram for LLNM. Receiver operating characteristic analysis and calibration curves were used to evaluate the predictive power of the nomogram. Results: The following were identified as independent risk factors for LLNM: male sex (odds ratio [OR] = 4.6, P =.04), tumor size ≥10.5 mm (OR = 7.9, P =.008), thyroid nodules (OR = 6.1, P =.013), irregular tumor shape (OR = 24.6, P =.001), rich lymph node vascularity (OR = 9.7, P =.004), and lymph node location. The dynamic nomogram constructed with these factors is available at https://zxh1119.shinyapps.io/DynNomapp/. The nomogram showed good performance, with an area under the curve of 0.956 (95% CI, 0.925-0.986), a sensitivity of 0.87, and a specificity of 0.91, if high-risk patients were defined as those with a predicted probability ≥0.3 or total score ≥200. The nomogram performed well in the external validation cohort (area under the curve, 0.915; 95% CI, 0.862-0.967). Conclusions: The dynamic nomogram for preoperative prediction of LLNM in papillary thyroid carcinoma can help surgeons identify high-risk patients and develop individualized treatment plans. [ABSTRACT FROM AUTHOR]