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This study examined the growth of the laser-damage performance in optical components under the fourth harmonic of Nd:glass laser irradiation (263 nm). The damage-growth threshold of the optical component was relatively low under 263 nm laser irradiation compared to 351 nm irradiation, owing to the higher energy level of 4 ω photons, and depended on the material characteristics. The preliminary growth of laser damage in fused silica and CaF2 under 263 nm laser irradiation is reported in this article. The damage growth coefficients of these two materials were obtained by continuously irradiating the optical components using a 263 nm laser with a pulse width of τ = 5 ns. The damage growth threshold of fused silica is lower than that of CaF2 because of differences between the materials. The damage characteristics, including the damage morphology and bulk damage, were analyzed. [ABSTRACT FROM AUTHOR]

Liver fibrosis is an important pathological process in chronic liver disease and cirrhosis. Recent studies have found a close association between intestinal microbiota and the development of liver fibrosis. To determine whether there are differences in the intestinal microbiota between rhesus macaques with liver fibrosis (MG) and normal rhesus macaques (MN), fecal samples were collected from 8 male MG and 12 male MN. The biological composition of the intestinal microbiota was then detected using 16S rRNA gene sequencing. The results revealed statistically significant differences in ASVs and Chao1 in the alpha-diversity and the beta-diversity of intestinal microbiota between MG and MN. Both groups shared Prevotella and Lactobacillus as common dominant microbiota. However, beneficial bacteria such as Lactobacillus were significantly less abundant in MG (P = 0.02). Predictive functional analysis using PICRUSt2 gene prediction revealed that MG exhibited a higher relative abundance of functions related to substance transport and metabolic pathways. This study may provide insight into further exploration of the mechanisms by which intestinal microbiota affect liver fibrosis and its potential future use in treating liver fibrosis. [ABSTRACT FROM AUTHOR]

The safety and stability of tunnel construction are paramount concerns in tunnel engineering. Traditionally, the assessment of tunnel stability involves evaluating whether tunnel displacement and deformation velocities exceed acceptable thresholds, using specifications and analogical reasoning. However, standardized cautionary indicators often lack adaptability and can result in unnecessary reinforcement and increase economic costs. This study presents a method for determining limit displacement and deformation velocities based on tunnel deformation limit states. Based on the finite difference method, which considers the quality of surrounding rock mass and tunnel geometric configuration, a parametric analysis of these velocities is presented. The vault settlement, relative spandrel displacement, relative hance displacement, and deformation velocity are investigated to establish the thresholds for displacement and deformation velocities. Furthermore, a sensitivity analysis using a multivariate adaptive spline regression model is performed to measure the parameter effects on the early allowance values. Finally, a response surface method is developed to estimate the indicators in order to provide criteria for assessing and warning about surrounding rock stability. The obtained results show that the proposed limit state analysis method is effective for providing a standardized criterion for tunnel excavation, and the sensitivity analysis indicates tunnel depth as the most influential factor on tunnel reliability. [ABSTRACT FROM AUTHOR]

Fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1c) are key indicators reflecting blood glucose control in type 2 diabetes mellitus (T2DM) patients. The purpose of this study is to establish a predictive model for blood glucose changes in T2DM patients after 3 months of treatment, achieving personalized treatment.A retrospective study was conducted on type 2 diabetes mellitus real-world medical data from 4 cities in Sichuan Province, China from January 2015 to December 2020. After data preprocessing, data inputting, data sampling, and feature screening, 16 kinds of machine learning methods were used to construct prediction models, and 5 prediction models with the best prediction performance were screened respectively. A total of 100,000 cases were included to establish the FBG model, and 2,169 cases were established to establish the HbA1c model. The best prediction model both of FBG and HbA1c finally obtained are realized by ensemble learning and modified random forest inputting, the AUC values are 0.819 and 0.970, respectively. The most important indicators of the FBG and HbA1c prediction model were FBG and HbA1c. Medication compliance, follow-up outcome, dietary habits, BMI, and waist circumference also had a greater impact on FBG levels. The prediction accuracy of the models of the two blood glucose control indicators is high and has certain clinical applicability.HbA1c and FBG are mutually important predictors, and there is a close relationship between them. [ABSTRACT FROM AUTHOR]

Fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1c) are key indicators reflecting blood glucose control in type 2 diabetes mellitus (T2DM) patients. The purpose of this study is to establish a predictive model for blood glucose changes in T2DM patients after 3 months of treatment, achieving personalized treatment.A retrospective study was conducted on type 2 diabetes mellitus real-world medical data from 4 cities in Sichuan Province, China from January 2015 to December 2020. After data preprocessing, data inputting, data sampling, and feature screening, 16 kinds of machine learning methods were used to construct prediction models, and 5 prediction models with the best prediction performance were screened respectively. A total of 100,000 cases were included to establish the FBG model, and 2,169 cases were established to establish the HbA1c model. The best prediction model both of FBG and HbA1c finally obtained are realized by ensemble learning and modified random forest inputting, the AUC values are 0.819 and 0.970, respectively. The most important indicators of the FBG and HbA1c prediction model were FBG and HbA1c. Medication compliance, follow-up outcome, dietary habits, BMI, and waist circumference also had a greater impact on FBG levels. The prediction accuracy of the models of the two blood glucose control indicators is high and has certain clinical applicability.HbA1c and FBG are mutually important predictors, and there is a close relationship between them. [ABSTRACT FROM AUTHOR]

To study the influence of shield excavation on the surrounding soil, and to control the influence of the shield excavation of the subway tunnel on the surface settlement and the deformation of the surrounding buildings, it is necessary to study the additional stress of the surrounding soil caused by the tunnel shield excavation and the law of surface settlement. Combined with a shield construction project of a subway tunnel, this article uses the Mindlin solution in elastic mechanics to obtain three-dimensional calculation formulas for the additional thrust on the shield cutter head surface and the additional stress and displacement field caused by the friction force between the shield shell and the soil contact interface on the surrounding soil. The Loganathan ground movement pattern is used to determine the soil movement mode. The source–sink method is used to study the formula for calculating the three-dimensional additional stress of the soil around the shield tunnel caused by ground loss. The results show that when the shield is digging, the ground goes through five stages, namely the uplift of the ground before the arrival of the shield cutter head, surface settlement when the shield reaches the surface subsides when the shield tail of the shield passes through, the passage of the shield tail of the shield, surface settlement when the lining is separated from the shield, and consolidation and settlement after the shield passes through. [ABSTRACT FROM AUTHOR]

The development of a battery management algorithm is highly dependent on high-quality battery operation data, especially the data in extreme conditions such as low temperatures. The data in faults are also essential for failure and safety management research. This study developed a battery big data platform to realize vehicle operation, energy interaction and data management. First, we developed an electric vehicle with vehicle navigation and position detection and designed an environmental cabin that allows the vehicle to operate autonomously. Second, charging and heating systems based on wireless energy transfer were developed and equipped on the vehicle to investigate optimal charging and heating methods of the batteries in the vehicle. Third, the data transmission network was designed, a real-time monitoring interface was developed, and the self-developed battery management system was used to measure, collect, upload, and store battery operation data in real time. Finally, experimental validation was performed on the platform. Results demonstrate the efficiency and reliability of the platform. Battery state of charge estimation is used as an example to illustrate the availability of battery operation data. [ABSTRACT FROM AUTHOR]

The characterization of energetic protons generated in the ShenGuang-II UP petawatt laser interactions with foil targets has been systematically studied. The proton energy spectra and angular distributions are measured with a radiochromic film stack. It shows that the proton energy spectra have a Boltzmann distribution with temperature of about 2.8 MeV and cutoff energy of about 20 MeV. The divergence angles of protons vary from 10° to 60°, dependent on the proton energy. The proton source size and location are investigated via the proton point-projection mesh imaging. The proton virtual sources are found to locate tens to hundreds of microns in front of the foil target, depending on the proton energies. A Monte Carlo simulation estimates the diameter of the virtual proton source to be about 12 μm for the protons with energy of 16.8 MeV, which is much smaller than the laser focus size of about 50 μm. The spatial resolution of the 16.8 MeV proton imaging is quantified with the point spread function to be about 15 μm, which is consistent with the proton virtual source size. These results will be important for the users conducting experiments with the protons as a backlighting source on the ShenGuang-II UP petawatt laser. [ABSTRACT FROM AUTHOR]

Relativistic electrons generated by the interaction of petawatt-class short laser pulses with solid targets can be used to generate bright x-rays via bremsstrahlung. The efficiency of laser energy transfer into these electrons depends on multiple parameters including the focused intensity and pre-plasma level. This paper reports experimental results from the interaction of a high intensity petawatt-class glass laser pulses with solid targets at a maximum intensity of 1019 W cm−2. In-situ measurements of specularly reflected light are used to provide an upper bound of laser absorption and to characterize focused laser intensity, the pre-plasma level and the generation mechanism of second harmonic light. The measured spectrum of electrons and bremsstrahlung radiation provide information about the efficiency of laser energy transfer. [ABSTRACT FROM AUTHOR]

We report on the design and first results from experiments looking at the formation of radiative shocks on the Shenguang-II (SG-II) laser at the Shanghai Institute of Optics and Fine Mechanics in China. Laser-heating of a two-layer CH/CH–Br foil drives a $\sim 40$  km/s shock inside a gas cell filled with argon at an initial pressure of 1 bar. The use of gas-cell targets with large (several millimetres) lateral and axial extent allows the shock to propagate freely without any wall interactions, and permits a large field of view to image single and colliding counter-propagating shocks with time-resolved, point-projection X-ray backlighting ($\sim 20$  μm source size, 4.3 keV photon energy). Single shocks were imaged up to 100 ns after the onset of the laser drive, allowing to probe the growth of spatial nonuniformities in the shock apex. These results are compared with experiments looking at counter-propagating shocks, showing a symmetric drive that leads to a collision and stagnation from $\sim 40$  ns onward. We present a preliminary comparison with numerical simulations with the radiation hydrodynamics code ARWEN, which provides expected plasma parameters for the design of future experiments in this facility. [ABSTRACT FROM AUTHOR]

Accurate temporal characterization both in intensity and phase distribution is important in the diagnosis of the petawatt (PW) class. We present a single-shot picosecond frequency-resolved optical gating (ps-FROG) setup based on an autocorrelator with ps measurement range that is spectrally resolved through a fine grating. The modified ptychographic-based algorithm with a changing update coefficient was used for the reconstruction of the pulse distribution; it can better adapt to the reconstruction of pulse with a large time–bandwidth product. We calibrated and verified the homemade ps-FROG in a 100-μJ ps laser system and used it to characterize the pulse distribution generated by the PW laser system of the Shen Guang II facility. The system shows good performance and high accuracy in reconstructing the intensity and phase distributions of a ps pulse, which provides reference for accurately adjusting the grating pair to acquire the pulse width as a preset. [ABSTRACT FROM AUTHOR]

A chromatic dispersion-free diffraction-grating single-shot autocorrelator (grating-SSA) is proposed. The grating-SSA is described theoretically, and its performance is experimentally characterized. The results demonstrate that the SSA measurement range can be expanded as expected, and the measurement accuracy is the same as that of a conventional SSA. The measurement range of an optimized design can be expanded to almost three times as wide as that of the same size BBO-based conventional SSA, achieving a 100 ps measurement range for an 30 mm diameter non-linear crystal. [ABSTRACT FROM AUTHOR]