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The extensive distribution and complex material composition of soil-rock mixture slopes in China have attracted significant attention from scholars. Objective This study aims to scientifically and rationally assess the impact of the spatial variability of soil parameters on the stability of soil-rock mixture slopes. Methods Based on the random field theory, the effective shear strength parameters cohesion c and internal friction angle φ are selected as random variables. The local averaging method is used to simulate the random field, with random field parameter generation conducted in MATLAB. Python scripts are employed to map the random field parameters to the soil-rock mixture slope via finite element software, accounting for the actual shape and content of block rocks in the soil-rock mixture. The strength reduction method is then applied to calculate the slope stability safety factor. Results The results reveal that the stability safety factor of soil-rock mixture slopes follows a normal distribution. As the block stone content increases, the mean value of the stability safety factor rises from 1.005 to 1.095, reflecting a transition from shallow to deep failure. For block stone content of 35%, the stability safety factor reaches 1.334 for larger block stones and 1.064 for smaller ones. Compared to deterministic calculation results, incorporating the spatial variability of the soil parameters yields higher stability safety factor. Conclusion Therefore, in soil-rock mixture slope stability analyses, the spatial variability of effective shear strength parameters must be fully considered to prevent overly conservative designs.

This study aimed to examine the impact of glass magnesium boards on the performance of metal faced rock wool sandwich boards. Through comparative experiments focusing on the bending capacity, coefficient of heat transmission, and fire resistance of metal faced rock wool sandwich boards, metal faced single glass magnesium rock wool sandwich board, and metal faced double glass magnesium rock wool sandwich board, the following results were obtained. Compared with the traditional metal faced rock wool sandwich boards, the bending capacity of the metal faced single glass magnesium rock wool sandwich board was increased by 7.14%, the coefficient of heat transmission was raised by 21.18%, and the fire resistance reached 61 minutes with a maximum temperature of 136.1 °C. In the case of metal faced double glass magnesium rock wool sandwich board, the bending capacity was enhanced by 32.14%, the coefficient of heat transmission was augmented by 30.59%, and the fire resistance also reached 61 minutes, with a maximum temperature of 79.6°C. This shows that adding glass magnesium board to the metal face rock wool sandwich board will reduce the thermal insulation performance of the whole structure, improve the bending capacity and fire resistance. Therefore, in practical applications, the effect of glass magnesium boards needs to be balanced and considered to achieve the optimized design of structural performance. [ABSTRACT FROM AUTHOR]

In order to improve the pointing accuracy of roll-pitch semi-strapdown photo-electricity stabilized platform, a method for error modeling and parameter calibration of stabilized platform is proposed. Based on the mechanical structure characteristics of the roll-pitch seeker, the main error sources of the stabilized platform are analyzed. Established the linear error model of the misalignment angle by using the coordinate transformation method and Taylor formula, and designed a method to improve the line-of-sight measurement accuracy of the stable platform by compensating the misalignment angle error. The least square method is used to design the calibration method of error parameters. The simulation results show that the error parameter calibration method can effectively calibrate the error parameters, and the method of compensating the misalignment angle error through the misalignment angle linear error model can significantly improve the line of sight pointing measurement accuracy of the stabilized platform.

The complex geological conditions of the Tibetan Plateau have historically fostered the development of numerous ancient landslides. In recent years, the reactivation of these landslides has exhibited a concerning escalation, driven by extreme weather events and human activities, thereby posing significant hazards. This study examines the Lumai ancient landslide in Shannan City, Xizang, employing a combination of field geological investigation, drone mapping, numerical simulation, and other technical methodologies. The research focuses on analysing the reactivation characteristics and influencing factors, specifically investigating the reactivation mechanism of the ancient landslide under the effects of surface water infiltration and loading. The results indicate that the Lumai ancient landslide has a volume of 2.5 x 106 to 15.1 x 106 m³. The maximum height difference between the landslide's leading edge shear outlet and the Dangxuxiongqu River at the slope foot exceeds 200 meters, with the deepest sliding zone located at the interface between bedrock and loose deposits. Deformation is primarily concentrated in the front part of the landslide's accumulation zone, characterized by numerous cracks and steep scarps. The reactivation is significantly influenced by surface water infiltration and overloading. Under concentrated water infiltration, localized sliding frequently occurs at the landslide front. Additionally, increased loading at the front leads to overall deformation and a tendency toward high-position shear failure. These findings enhance the understanding of reactivation mechanisms for ancient landslides in the Shannan City, Xizang, and provide valuable insights for local disaster prevention and mitigation efforts. [ABSTRACT FROM AUTHOR]

Thermoelectric refrigeration is a solid-state refrigeration technology that uses electric energy to achieve refrigeration via the Peltier effect. Compared with vapor compression refrigeration, thermoelectric refrigeration offers the advantages of scalability, vibration-free, high reliability, and high temperature-control accuracy. Based on the development history and basic principles of thermoelectric refrigeration, this study focuses on the research progress of thermoelectric materials, refrigerator structures, functional layer interfaces, and heat sinks. Subsequently, applications of thermoelectric refrigeration are introduced based on their advantages. Finally, investigations regarding thermoelectric refrigeration are summarized and discussed.

With the continuous development of data centers, the energy consumption and heat flux of information technology (IT) equipment has gradually increased, and the energy consumption of supporting refrigeration equipment increases proportionally. Consequently, efficient and energy-saving cooling technologies have gradually attracted considerable attention. In this study, existing two-phase cooling techniques were summarized and classified, and the distributed two-phase cooling method was proposed. By contrast, the research progress of two-phase cooling technology was introduced in three aspects: the properties of working fluids for data center cooling, enhanced heat transfer methods, and thermodynamic evaluation of cooling systems. The research on the working fluids mainly focused on the liquid properties, and the gaseous properties were rarely reported. The heat transfer of boiling and condensation was mainly strengthened by the formation and separation of bubbles and droplets. Research on enhanced heat transfer methods for liquid cooling was insufficient. The two-phase cooling system had an excellent thermodynamic performance. However, the pressure change caused by the phase change is undesired.

Many electronic devices can benefit from operating at low temperatures. However, the widespread use of cryogenic electronic devices is limited by the miniaturization of cryocoolers. In this study, a closed Joule-Thomson (JT) cooling system based on a multicomponent mixture was investigated. The system comprised a Hampson-JT microcooler and a linear compressor. The working fluid was a ternary mixture with a molar concentration of 39% methane, 20% ethane, and 41% isobutane. The cooling performance of a refrigerator under different conditions was studied experimentally. The results show that the microcooler can achieve a cold-end temperature of 165 K under 0.10–1.77 MPa and 0.14–1.90 MPa pressure, and 198 K under 0.36–1.73 MPa and 0.18–1.36 MPa pressure. The compact structure of the cooling system promotes the application of cryogenic electronic devices in the fields of military, space science, and biomedicine.

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The process mineralogy of the middle and low grade phosphorus block rocks in Zhijin area of Guizhou province was studied. Mineral composition, chemical composition, distribution characteristics and mineral particle size distribution of the ore were ascertained. It was found that the main mineral in this area was fluorapatite, while gangue was mainly quartz. Fluorine apatite content was 57.62%, dolomite content was 25.34%. The ore also contained a small amount of quartz, pyrite, calcite and so on. Fluorapatite had a close relationship with dolomite and quartz, and the intergrown relationship was mainly intergrowths with three of more phases. By means of automatic process mineralogical parameter analysis system (BPMA), X-ray diffraction (XRD), X-ray fluorescence spectrometer (XRF) and other analysis methods combined with process mineralogical analysis, a two-stage reverse flotation process for magnesium removal was determined, and the P2O5 grade of the concentrate obtained being 32.40%. The MgO in the concentrate decreased from 12.50% to 1.60%, and the recovery of the phosphorus concentrate was 85.13%. The beneficiation index was satisfactory, which provided certain technical basis for the development and utilization of the phosphate ore in this area. [ABSTRACT FROM AUTHOR]

Adhesive polydopamine nanocapsules containing hexamidine diisethionate (PDA@ HD nanocapsules) were prepared using W1 / O/ W2 emulsion templating to enhance wet adhesion capacity of HD. Thereafter, the morphological structure, loading and release properties, adhesion properties and acute toxicity to zebrafish embryos of PDA were investigated. The results showed that the PDA@ HD nanocapsules were spherical with a distinct coreshell structure whose average particle size was 353 nm. The loading ratio of PDA@ HD nanocapsules could be effectively increased by increasing the concentration of HD in W1 phase of W1 / O/ W2 emulsion. Specifically, by increasing the concentration of HD to 18 mg/ mL,the loading ratio of PDA@ HD nanocapsules increased to 17.1%. The release of HD in PDA@ HD nanocapsules exhibited a clear pH dependence and PDA@ HD nanocapsules showed better release properties in acidic environment. The adhesion force of PDA @ HD nanocapsules was effectively increased about 3 times that of HD. The PDA@ HD nanocapsules reduced the acute toxicity to zebrafish embryos. When the concentration of HD in PDA@ HD nanocapsules was 0.5 mg/ mL, all zebrafish embryos survived till 96 hpf. [ABSTRACT FROM AUTHOR]

In recent years, as a new visible light responsive nonmetal photocatalyst, graphite-phase carbon nitride (g-C3 N4) has been widely used for organic pollutants removal in photocatalysis system due to its suitable band gap width characteristic, enough active sites and low cost. However, the drawback of its low visible-light utilization and fast recombination of photogenerated electron-hole pairs that play negative effect on its photocatalytic activity. Combine with the nonmetal properties of g-C3 N4, nonmetal doping is an effective strategy to further improve the photocatalytic performance of g-C3 N4, and has attracted more and more attention on photocatalysis. In this paper, the common preparation methods of non metal doped g-C3 N4 composite materials are introduced. In addition, the research progress of different nonmetal doped g-C3 N4 applied in photocatalytic degradation of organic pollutants is summarized in detail, and its mechanism of photocatalytic degradation of organic pollutants under visible light is also discussed. Finally, the challenges and suggestions for the photocatalytic degradation of organic pollutants in water by nonmetal doped g-C3 N4 are proposed, and this review also helps to provide insights into the removal of organic pollutants by nonmetal doped g-C3 N4 coupled photocatalysis. [ABSTRACT FROM AUTHOR]

In recent years, as a new visible light responsive nonmetal photocatalyst, graphite-phase carbon nitride (g-C3 N4) has been widely used for organic pollutants removal in photocatalysis system due to its suitable band gap width characteristic, enough active sites and low cost. However, the drawback of its low visible-light utilization and fast recombination of photogenerated electron-hole pairs that play negative effect on its photocatalytic activity. Combine with the nonmetal properties of g-C3 N4, nonmetal doping is an effective strategy to further improve the photocatalytic performance of g-C3 N4, and has attracted more and more attention on photocatalysis. In this paper, the common preparation methods of non metal doped g-C3 N4 composite materials are introduced. In addition, the research progress of different nonmetal doped g-C3 N4 applied in photocatalytic degradation of organic pollutants is summarized in detail, and its mechanism of photocatalytic degradation of organic pollutants under visible light is also discussed. Finally, the challenges and suggestions for the photocatalytic degradation of organic pollutants in water by nonmetal doped g-C3 N4 are proposed, and this review also helps to provide insights into the removal of organic pollutants by nonmetal doped g-C3 N4 coupled photocatalysis. [ABSTRACT FROM AUTHOR]

In this research, a zebrafish stimulation model was established based on zebrafish embryonic behavior. The soothing effects of dipotassium glycyrrhizinate and baicalein were verified and compared with the traditional zebrafish inflammation model. Then, the soothing efficacy of five cosmetic raw materials including α-red myrrh alcohol, paeonol, asiaticoside, proantho cyanidins and 4-tert-butylcyclohexanol was selectively evaluated by this model. The results showed that compared with 4-butyl-resorcinol, sodium dodecyl sulfate was a more stable modeling agent. The zebrafish stimulation model constructed by SDS concentration of 500 μmol/ L and 15 min on zebrafish embryos was used to evaluate the soothing effects of dipotassium glycyrrhizinate and baicalein, and the results were basically consistent with the zebrafish inflammation model. At high concentrations, α-red myrrh alcohol, paeonol, asiaticoside and proantho cyanidins showed significantly soothing efficacy in the zebrafish stimulation model. [ABSTRACT FROM AUTHOR]

Changes in the plasma metabolism of young ICR mice after exposure to nano-TiO2 at different doses were measured to investigate the mechanism of its toxic side-effects and to identify its toxicity-related biological targets. Mice were assigned randomly to control group and nano-TiO2 (10, 30, 100, or 300 mg⋅kg-1 ) exposure groups. Plasma data were analyzed using metabonomics technology to identify potential biomarkers. Topology of biomarkers was determined using the KEGG database. Contents of cholic acid, deoxycholic acid, ursodeoxycholic acid and taurocholic acid in plasma were measured by targeted quantitative methods to find the biomarkers corresponding to the toxic effects of TiO2. Forty-nine metabolites were screened from plasma. The toxicity of nano-TiO2 resulted mainly from an abnormality of phospholipids and bile-acid compounds. The toxicity of nano-TiO2 in mice after 28 d exposure may be related to the abnormal metabolism of phospholipids and bile-acid compounds. [ABSTRACT FROM AUTHOR]

Based on observation data of dense automatic meteorological stations, conventional radio-soundings, meteorological satellite, Doppler weather radar, and combined with European Center for Medium-Range Weather Forecasts (ECMWF) 6 hours re-analysis data (0.25° X 0.25°), the mesoscale environmental fields and its mainly characteristics of extremely rainstorm in eastern Henan province produced by Typhoon "Rumbia" (1818) which deeply entered Henan province in 2018 were analyzed, and the physics causes of extremely rainstorm were also preliminary explored. The results indicate that extremely rainstorm areas located the superposition of 700 hPa warm advection and positive differential vorticity advection between 500 hPa and 850 hPa, and with large humidity in middle-low level and surface layer, obvious convective instability energy in upstream of rainstorm areas. Strong bow echo band in radar echo reflectivity and a corresponding strong northeasterly and southeasterly winds in radar radial velocity in low level and a relating high value band of vertical integrated liquid water were stable lasting for a long time during the extremely rainstorm. Strong water vapor transport zones which formed by downwards development of southeast or south jet streams during the strong rainfall provide the Water vapor source for extremely rainstorm. There are strong water vapor convergence in middle-low level and strong water vapor divergence in high level at extremely rainstorm areas. The effect of the eastern stream with high moist and convective unstable characteristics was uplifted and obstructed by Taihang Mountains, which was one of the important reasons for the formation of typhoon torrential rain. The combinational development of the southerly flow in the western and northern side of typhoon system and the strong southwesterly stream at levels of 150-250 hPa has an indicative role for the changes of steering flow and track turning of typhoon system. [ABSTRACT FROM AUTHOR]

Objective To investigate the clinical value of contrast-enhanced ultrasonography (CEUS) in assessing the high-risk population of hepatic malignant tumor (HMT). Methods Three hundred patients with high-risk of HMT were enrolled and examined by CEUS. The clinical data of these patients were collected. A comparative analysis was performed to assess the ability of CEUS for detecting and characterizing lesions in the liver. Kappa test was used for assessing the intra-and inter-observer reliability of CEUS. Results In 87 enrolled patients with 119 malignant lesions detected by contrast-enhanced MKI. 112 lesions were detected by CEUS and 95 lesions were detected by unenhanced ultrasonography ( US). The detection rate of CEUS for HMT was significant higher than that of US (94.1% vs. 79.8% ; P<0.01). More HMT lesions were detected by CEUS than by US in 17.2% patients. One hundred and seventy-seven patients with 215 lesions were confirmed by pathological diagnosis or long-time follow-up. There were 118 malignant and 97 benign lesions. The accuracy of CEUS for differential diagnosis of the liver lesions was 91.6% ( 197/ 215), significantly higher than that by US (59.1%, 127/215) (P<0.01). CEUS improved the accuracy for 35.0% (62/177) patients. For 96 patients with 105 lesions detected for the first time, the agreement of diagnosis by CEUS was 92.4% (97/105). The reliability of CEUS was high (Kappainter =0.866; Kappaintra = 0.934). Conclusions CEUS improves the detection rate and diagnostic accuracy rate of the HMT high-risk population, with a high agreement for diagnosing the new lesions. CEUS may be considered as a first-line method to assess the high-risk population of HMT conveniently, accurately and reliably. [ABSTRACT FROM AUTHOR]

A full dynamic production model of pressure vessel was developed using HYSYS Dynamics™ by taking a gas field slug catcher as an example. The PSV relieving of slug catcher with different initial pressure and liquid level on external pool fire scenario was studied by the dynamic model. The results showed that initial conditions affected the PSV relief rate significantly. The affection of initial conditions should be considered sufficiently when calculating the maximum PSV relief rate, so as to provide correct basic parameter in PSV sizing and selecting. [ABSTRACT FROM AUTHOR]

There are some problems such as a large amount of liquid slug existing and the difficulty of pig's speed control when the pipeline pigging operations are conducted by traditional pig. Recently, by pass pigging is becoming the key innovation technology because it can effectively reduce liquid slug and realize redistribution of the chemicals such as corrosion inhibitors. In this paper, on the basis of the by pass analyses technology, the gas-condensed submarine pipeline pigging model is set up by using the multiphase flow dynamic simulation software OLGA, and the effects of the pipeline parameters, operating conditions, and the seabed environment to the by pass pigging are simulated. On this base, the comparisons between the traditional pigging and he by pass pigging have been done through the changes of pigging velocity, pressure, and liquid lug etc. Meanwhile the optimum by pass rate is obtained which provides guidance for the practical applications of by pass pigging. [ABSTRACT FROM AUTHOR]

In view of the slip pile depth prediction in pile construction is concentrated on pile driving risk analysis of large diameter and super-long piles, but the slip depth and slip pile mechanism of offshore riser construction is lack of study, which means blindness and risk exist in operation. The geometrical relationship between conductor and offshore platform during pile driving operation, the ultimate bearing capacity of conductor and the slip pile mechanism were analyzed, and then the theoretical prediction model of the slip depth for offshore conductor driving construction was proposed. The theoretical prediction model of slip depth has been successfully applied in several wells in an offshore oil field, and the actual slip depth of conductor driving is nearly in line with the calculated result. The research achievements provide the theoretic foundation for risk assessment of conductor operation, and ensure security for offshore drilling. [ABSTRACT FROM AUTHOR]

Objective The process of a stainless steel train body derailment accident in urban rail transit in 2015 is simulated, reproducing the direct cause and process of the car body damage in the complex accident scene. Method Based on the investigation of the accident scene and the stainless steel car body structure and characteristics, the finite element method is used to reconstruct the accident model and analyze the changes of the speed, acceleration and energy of the train. Result & Conclusion Simulation results show that the intermediate cars climbing, snaking and colliding with each other caused by huge energy and rugged ground at the time of the accident forms the main reason for the fracture failure of stainless steel car body structure in the accident. The car body fractures mainly locate at the connections between the cab frame and the under-frame, the end wall and the roof, the under-frame and the side wall, as well as the under-frame and the end wall.

[Objective] Energy transition is a key path to achieving China’s carbon peaking and carbon neutrality goals, and exploring the impact of energy transition on the urban-rural income gaps can provide a scientific basis for realizing equity in the transition. [Methods] Based on the panel data of 108 cities at the prefecture level and above in the Yangtze River Economic Belt from 2010 to 2020, this study employed spatial analysis and fixed-effects model to analyze the characteristics of the temporal and spatial change of energy transition and urban-rural income gaps, and to reveal the correlation between the two and their regional heterogeneity of this relationship. [Results] (1) The performance level of energy transition of cities in the Yangtze River Economic Belt shows an overall upward trend, and the energy transition index values of provincial capital cities has remained at a high level for a long time. At the same time, urban-rural income gaps have been narrowing year by year, showing a pattern of high in the west and low in the east. (2) The relationship between energy transition and urban-rural income gaps in cities in the Yangtze River Economic Belt was U-shaped. With the improvement of the performance level of energy transition, urban-rural income gaps showed the characteristic of decreasing and then increasing. (3) There was a significant difference in the relationship between energy transition and urban-rural income gaps in cities in the upper, middle, and lower reaches of the Yangtze River, with the upstream showing an inverted U-shaped relationship and the middle reaches showing a U-shaped relationship, and the downstream showing no significant correlation. This suggests that the energy transition paths of cities in the upstream region were gradually moving towards a fair direction, while the opposite was true in the midstream region, and that urban and rural residents in the downstream region were less sensitive to the socioeconomic effects caused by energy transition. [Conclusion] Therefore, diversified energy transition policies should be formulated in accordance with the actual development of the upstream, midstream and downstream, so as to effectively prevent the negative impacts of the transition and actively promote the just energy transition and the balanced development of urban and rural regions.

The development of advanced nuclear energy systems imposes stringent requirements on the service stability of nuclear materials under extreme environments characterized by multiple stressors. Continuous silicon-carbide-fiber-reinforced silicon carbide (SiCf/SiC) ceramic matrix composites possess advantages such as low density, excellent high-temperature mechanical properties,corrosion resistance, and irradiation tolerance. Furthermore, SiCf/SiC composites demonstrate a pseudo-ductile fracture behavior under external forces, positioning them as highly promising structural materials for advanced nuclear energy systems. This study systematically summarizes the fundamental research framework on nuclear-grade SiCf/SiC composites at the material, component,and service performance levels. It also analyzes the developmental trends in this field among traditional nuclear powerhouses such as the United States, France, and Japan, as well as in other emerging nuclear energy countries and China. Furthermore, the study identifies existing issues and challenges faced by China’s nuclear-grade SiCf/SiC sector in terms of raw materials, data accumulation,and patent standards, and proposes targeted measures and suggestions: (1) strengthening the research and development of material preparation technologies, (2) developing a new paradigm of research and development, (3) reinforcing the industry-universityresearch-application cooperation, and (4) enhancing international exchanges on the basis of maintaining independence. The aim of the study is to provide guidance and reference for the research directions and policy-making in China’s nuclear-grade SiCf/SiC sector.

Low accuracy of extended forecast remains an important scientific problem in the current stage， and qualified extended forecast is of great significance for disaster prevention and mitigation.In this study， the machine learning method was used to forecast the summer precipitation during the extension period （5~30 days） in China， and explore the possible contribution of soil moisture to extended forecast of precipitation.Based on the results， machine learning methods remarkably outweigh traditional linear models in terms of forecast accuracy， with Catboost， Lightgbm and Adaboost being the optimal machine learning methods.According to further analysis， the abnormal evaporation and sensible heat anomaly caused by the surface soil moisture anomaly in the Yangtze River Basin can lead to the atmospheric circulation and vertical movement anomaly， which eventually affects summer precipitation.The set of three optimal machine learning methods was applied to calculate the contribution rate of each forecasting factor in the model.It was found that the local soil moisture dominated the extended precipitation in the Yangtze River Basin from the 5th day to the 10th day， while the local soil moisture played a dominant role on previous precipitation from the 10th day to the 15th day， and the extended precipitation in the Yangtze River Basin during the period of Day 20~30 was basically controlled by large-scale circulation.Besides， the influence of non-local soil moisture on extended precipitation was evaluated， the results of which showed that the surface soil moisture in Indo-China Peninsula mainly contributed to the extended precipitation in the Yangtze River Basin from the 15th day to the 30th day.By adding the surface soil moisture of Indo-China Peninsula to the extended precipitation model in Northeast China， it was found that surface the soil moisture failed to improve the extended forecast accuracy of precipitation in this area， which verified the availability of the machine learning model.This study provides a certain reference for forecasting precipitation in the extended period and exploring the contribution rate of forecasting factors.

[Objective] Survival of species seedlings is closely related to various biotic and abiotic factors. Exploring the key factors affecting seedling survival is helpful for the understanding of species coexistence mechanisms. [Methods] This study was focused on the survival dynamics of the woody species seedlings in a 25 hm2 permanent forest of a deciduous broad-leaved forest in the Qinling Mountains, and the survivals of 11 408 seedlings were examined for five consecutive years (2015-2019). The generalized linear mixed models (GLMMs) were used to examine the effect of maior biotic and abiotic factors on the survival of seedlings of different ages at the community level. [Results] (1) At the community level, biotic factors played a major role in seedling survival. Seedling survival was negatively correlated with conspecific seedling density and basal area of conspecific adults. It also positively correlated with interspecific seedling density. The results showed that negative density-dependence (NDD) had significant effects on seedling dynamics. (2) From the seedling age level, in addition to biological factors, abiotic factors such as altitude also affected seedling survival. The effect of abiotic factors decreased with the increase of seedling age. [Conclusion] There are many factors affecting seedling survival, among which biological factors are more significant, and the main mechanism promoting seedling coexistence is the negative density restriction effect in the Qinling Mountains.

This study explored the inhibitory effect and mechanism of the culture supernatant of Lactiplantibacillus plantarum HB13-2 on Candida albicans. The minimum inhibitory concentration was determined by the double dilution method. Then, the fluorescent dye calcofluor white (CFW) was used to stain the cell wall and observe it. The results showed that the supernatant enhanced the fluorescence intensity and damaged the cell wall. Flow cytometry and fluorescence microscopy showed that the supernatant changed the membrane permeability of C. albicans. The transmembrane potential was detected using the fluorescent probe DiSC3(5), and it was found that the fluorescence intensity was enhanced, indicating that the supernatant caused dissipation of the transmembrane potential. Through microstructural observation by scanning electron microscopy (SEM), it was found that the supernatant of Lactobacillus plantarum HB13-2 caused cellular deformation and leakage of intracellular contents. As detected by fluorescence staining with 2’,7’-dichlorodihydrofluorescin diacetate (DCFH-DA) and Rhodamine-123, the supernatant resulted in accumulation of a large amount of intracellular reactive oxygen species (ROS) and increased mitochondrial membrane potential. In conclusion, the supernatant of L. plantarum HB13-2 can deform cells by destroying the cell wall and membrane and lead to mitochondrial damage, thereby inhibiting C. albicans. This study will provide a scientific basis for the development of L. plantarum HB13-2 as an oral probiotic.

A finite-fault earthquake slip model can characterize the kinematics of rupture, which is essential for earthquake mechanism studies and seismic hazard assessments. The finite-fault model of an earthquake can be inverted from a wide range of geodetic measurements and seismic recordings. The linear least squares method minimizes misfits between observations and forward modeling and is a common approach in finite-fault inversion problems. This method may not yield the most plausible finite-fault model and has four main limitations. First, total parameter spaces are challenging to explore, and non-Gaussian parameter uncertainties cannot be evaluated. Second, to improve the stability of the fault slip inversion, fault slip smoothing operators (regularization techniques) are usually applied; however, determining the strength of smoothing a fault slip distribution is subjective. Third, the fault geometry needs to be predetermined, and different fault geometry settings can result in varying inversion results. Fourth, it is difficult to account for uncertainties in forward modeling because of imprecise Earth velocity models. In contrast, Bayesian inversion determines the probability density distribution of the model parameters, providing a globally optimized solution to all model parameters and characterizing trade-offs between pairs of model parameters. Therefore, the Bayesian approach effectively overcomes the problems encountered in linear inversion. With the rapid improvement in computer technology, Bayesian inversion has become highly developed, especially in the past decade. This review reports the results of recent Bayesian finite-fault inversion studies and explains the theory and methodology of Bayesian finite-fault inversion.

Objective: To investigate the diagnostic value of dual-source CT (DSCT) in evaluating adults with atrial septal defect (ASD) with pulmonary hypertension (PAH). Methods: Seventy-five adult patients with ASD in our hospital were retrospectively analyzed. The study sample was divided into 2 groups (PAH group (n=40) and non-PAH group (n=35 cases)) according to the mean pulmonary artery pressure (mPAP) obtained by right cardiac catheterization (RHC) (PAH: ≥ 25 mmHg). All patients were examined for congenital heart disease by DSCT one week before RHC. The ascending aorta diameter (AAD), main pulmonary artery diameter (MPAD), right pulmonary artery diameter (RPAD), left pulmonary artery diameter (LPAD), right lower pulmonary artery diameter (RLPAD), the maximum diameter of the short axis of both the ventricles (RVD, LVD), included the angle of the spinal ventricular septum and ASD diameter, were measured on the image. The MPAD to AAD ratio (rPA) and the RVD to LVD ratio (RVD/LVD) were calculated. Differences between the two groups in terms of clinical data, RHC indexes, and CT cardiovascular parameters were evaluated by a t-test. The ROC curve was used to determine the diagnostic efficacy of DSCT in adults with ASD and PAH. Pearson correlation coefficient was used to analyze the association between the CT parameters, mPAP, and PVR. Results: The statistically significant CT indexes between the two groups were MPAD, RPAD, LPAD, RLPAD, RVD including the angle of the spinal ventricular septum, rPA, RVD/LVD, and ASD diameter. Of these, the RPAD and LPAD including the angle of the spinal ventricular septum, rPA, RVD/LVD, and ASD diameter demonstrated moderate diagnostic efficacy for PAH (AUC>0.7). The MPAD, rPA, and ASD diameter with mPAP were moderately positively correlated. The MPAD, rPA, and RVD/LVD with PVR were also mildly positively correlated. Furthermore, the ASD diameter and PVR were highly positively correlated. Conclusion: DSCT is diagnostically valuable for the evaluation of adults with ASD complicated with PAH. In particular, DSCT may be used to provide a comprehensive evaluation before clinical treatment, as well as for long-term follow-up and management.

Due to its unique wearing comfort, operational flexibility and human-machine cooperation, the supernumerary robotic limb has a wide range of applications, such as medical rehabilitation, the aerospace, industrial production and building decoration, etc. This study analyzes the research status and development trend of supernumerary robotic limb at home and abroad, and reviews the design of the external limb structure, motion modeling, human-machine information interaction and coordination control. Meanwhile, the advantages and disadvantages of rigid external limb and flexible external limb are analyzed, the core and key of the motion modeling of the external limb are illustrated, and the technical challenges of human-machine interaction and optimal cooperative control are revealed. Finally, the main research points of the supernumerary robotic limb are summarized, and its future development direction and trend are prospected.

This study aimed to characterize the structure of Passiflora edulis Sims peel polysaccharide-zinc (WPEP-Zn) and its prebiotic effects. The structural characteristics of WPEP-Zn were determined using Fourier transform infrared spectrometer, X-ray diffractometer, scanning electron microscope, Congo red test, and thermogravimetric analyzer. The WPEP-Zn was used as carbon source to study its prebiotic effects on Lactobacillus plantarum, Lactobacillus delbrueckii (subsp.) bulgaricus, Lactobacillus brevis, and Streptococcus thermophilus. The results showed that WPEP-Zn had sugar and uronic acid content of 23.26% and 50.46%, respectively, whereas the zinc content was 10.64 mg/g. It had a triple helix structure compared with the Passiflora edulis Sims peel polysaccharide (WPEP). Its relative crystallinity decreased, the infrared absorption peak changed, the morphological structure altered, and the thermal stability enhanced. The optimal concentrations of WPEP-Zn used to promote the growth of the four bacteria strains were 3%, 2%, 2%, and 2%, respectively. The prebiotic effects of WPEP-Zn on L. plantarum, L. delbrueckii (subsp.) bulgaricus, and L. brevis were lower than WPEP, but its prebiotic effect on S. thermophilus was higher than the WPEP. The findings revealed the prebiotic effect of WPEP-Zn. The study on WPEP-Zn provided a basis for developing new polysaccharide-zinc supplements and the effective utilization of passion fruit resources.

Bacterial spores are extremely resistant to various processing techniques attributable to its special structure and physiological processes, and often lead to the spoilage of thermally sterilized food. Therefore, it is of great significance to inactivate spores or control spore germination in the food industry. This review summarizes the structure and the sporulation regulation mechanism in the formation process of bacterial spores, germination process and the factors of spore germination; then reviews the effects and mechanisms of action of some physical technologies (i.e., heat treatment, ultrasonic treatment, high pressure treatment and plasma treatment), chemical technologies (i.e., surfactants and chemical preservatives) and natural bio-antibacterial agents individually or in combination with other treatments against spore. This review is expected to provide reference for the development of safer and more efficient control technology of bacterial spores.

This study aimed to determine the effect of sulfated xylans on the growth of probiotics. Xylan (Xyl) was chemically modified using the sulfamic acid-N,N-dimethylformamide method to produce sulfated xylan (SXY). The SXY was characterized by Fourier infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and Congo red experiment. The Xyl and SXY were tested for their in vitro prebiotic effects using four strains of intestinal microflora, including Lactobacillus delbrueckii subsp. bulgaricus (GIM1.155), L. plantarum (GIM1.191), L. brevis (GIM1.773), and Streptococcus thermophilus (GIM1.540). From the recorded infrared spectra, vibrational bands for SXY were observed at 894, 1052 and 1243 cm−1, they could be assigned to the C—O—S vibration of a C—O—SO3, C—O stretched and S＝O stretching vibrations. The results of scanning electron microscopy showed that the surface structure of SXY increased smoothness. Congo red experiment revealed that SXY had a triple helix structure. The substitution degree of SXY measured using a BaCl2-gelatin turbidimeter was 0.341. In vitro experiment showed that the optimum concentration of SXY for the in vitro probiotic growth was 2.0%, rapid growth and increased proliferation were observed after 10 h of culture. The results obtained suggest that SXY could promote probiotic growth. It is an alternate source of prebiotics for maintaining gut health.

The purpose of this study is to select lactic acid bacteria with a strong ability to inhibit oral pathogens, high safety and strong oral colonization capacity. Firstly, the strains that could inhibit Streptococcus mutans and Streptococcus gordonii were screened from lactic acid bacteria resource bank in the laboratory by Oxford cup diffusion method. The 28 selected strains were evaluated for hemolytic activity. The results showed that seven of the 28 strains showed α-hemolysis while the remaining 21 did not. The antibacterial metabolites of 16 strains without hemolysis and with a diameter of inhibition zone ≥ 10 mm against S. mutans and S. gordonii were determined by neutralization, catalase and protease susceptibility assays. Then seven strains with strong bacteriostatic capacity and the potential to produce non-organic acid antimicrobial metabolites were selected. The safety evaluation results showed that all seven strains had low acid production ability and caused low corrosion to teeth. The highest tolerable concentration of lysozyme for strain JZ14-1 was 1.6 mg/mL, while that for the other six strains was 1.2 mg/mL, indicating that all seven strains could tolerate lysozyme. Strain HB13-2 was most susceptible to antibiotics. The oral colonization capacity evaluation of strain HB13-2 showed the following results: the highest hydrophobicity of 44.00%, surface acid charge of 20.16%, surface base charge of 49.44%, and content of exopolysaccharides of 0.283 mg/mL. This strain could easily colonize in oral cavity and had low biofilm formation capacity and good self-aggregation capacity, and the maximum inhibition percentage against S. mutans biofilm was 59.72%. Moreover, strain HB13-2 had strong copolymerization capacity with S. mutans, and the copolymerization capacity was 67.40% at 24 h. In conclusion, strain HB13-2 has good antibacterial activity, high safety and strong oral colonization capacity. It is identified as Lactiplantibacillus plantarum by 16S rDNA sequencing.

Pectic oligosaccharides (POS), small molecular polymers, can be prepared from pectin by different methods. Compared with natural pectin, POS have lower molecular mass, better water solubility, higher bioavailability, and more diverse biological activities. A series of POS with different molecular masses and structures can be obtained under different preparation conditions. In addition, the biological activities of POS are closely related to their molecular mass and structures. This review aims to comprehensively summarize the preparation, purification, structure analysis, and biological activity of POS, in order to provide some references for their applications as natural active substances in the fields of food, medicine, and health products.

Background Chronic obstructive pulmonary disease (COPD) is a global public health problem with increasing incidence and mortality. Fatigue is a common complaint of COPD patients, which seriously impairs the quality of life. Objective To conduct a scoping review of current research status and tools about fatigue as well as fatigue-related factors in COPD, providing ideas for the development of relevant individualized intervention schemes. Methods Methodological framework was used. Studies on fatigue in COPD were searched from databases of Web of Science, PubMed, EmBase, CINAHL, ProQuest, the Cochrane Library, CNKI, WanFang, CQVIP, and SinoMed from inception to July 2022, and enrolled according to the inclusion and exclusion criteria. Relevant data were extracted, collected, summarized and reported. Results A total of 52 studies were included. Taken overall, a wide variety of assessment tools for fatigue in COPD featured by lack of multidimensionality and specificity were used, among which common were the Functional Assessment of Chronic Illness Therapy and the Fatigue Severity Scale. There were certain disparities in the incidence, duration, and severity of fatigue in COPD across studies. The main influencing factors of fatigue include sociodemographic factors, COPD-related factors, somatic factors, and psychological factors. Conclusion As fatigue is a major symptom that seriously declines the quality of life in COPD patients, clinical care providers need to use specific tools to accurately assess fatigue, and to develop individualized interventions to improve fatigue according to its influencing factors.

Objective: To study the effects of dietary fibers with different structures on calcium balance and biomechanical properties. Methods: Rats were fed a basal diet supplemented with 50 g/kg wheat bran, cellulose, xylan, pectin, inulin, konjac gum or their mixture. The contents of calcium in diets, feces, urine and femur were detected by atomic absorption spectrometry (AAS). The levels of total calcium, free calcium and bound calcium in serum were measured by an electrolyte analyzer. The maximum load of femur was measured by a three-point bending method. The effects of different dietary fibers on calcium absorption, blood calcium level, urinary calcium loss, calcium retention, bone calcium content and bone biomechanical properties were compared. Results: The calcium absorption rates in the wheat bran and cellulose supplementation groups were higher than those in the xylan, pectin, inulin and konjac supplementation groups, and the difference between the xylan and konjac supplementation groups and the wheat bran supplementation group was significant (P 0.05), but the concentrations of bound calcium and total calcium in the wheat bran supplementation group were higher than those in the other groups. The bone calcium content and bone biomechanical properties in the pectin supplementation group were significantly lower than those in the other groups, and the maximum load of femur was the highest in the xylan supplementation group. Conclusion: The intestinal calcium absorption of low fermentable dietary fibers such as wheat bran and cellulose is higher than that of high fermentable dietary fibers such as xylan, pectin, inulin and konjac. Xylan can improve the biomechanical properties of rat bones. Different dietary fibers have different effects on calcium absorption, bone calcium content and calcium balance in rats.

In order to meet the requirements of machining accuracy indexes such as the entry, exit and shape of micro-hole, a multi-objective parameter optimization weigh method for micro electrical discharge machining（EDM） based on grey relational analysis（GRA） and entropy weight method is proposed.By designing orthogonal experiment and processing test for H62 brass, the grey relational coefficient of each index of the experiment result sequence is calculated.The entropy weight method and grey relational analysis method are used to comprehensively evaluate the model, and the grey relational degree of each experiment sequence is obtained, and the mean value analysis is carried out to realize the transformation from multi-objective optimization to single objective optimization.The research results show that the entry Overcut（EnOV）, exit Overcut（ExOV） and taper（TA） of the optimized process parameters are reduced by 8.97%, 4.11% and 8.33% respectively compared with those of the H-22 group with the largest grey relational degree, and the machining accuracy of micropores is improved.

With the rapid increase in the number of preferential tax policies, taxpayers face a large number of preferential tax policies, and it is difficult for taxpayers to quickly locate the preferential content related to them.As a result, many taxpayers do not enjoy the preferential policies they should enjoy.Based on the combination of pre-training language model BERT and rule processing, the visualization was realized of the characterization of preferential tax policies and regulations, the extraction of key elements, and the visual query of tax incentives, so that taxpayers can intuitively and quickly locate tax incentives related to themselves, and visualize the results.The experimental results show that the extraction performance of key elements is superior, and the query of preferential tax policies is quick and intuitive, which can effectively alleviate the problem of massive tax preferential information overload.