Search

To investigate the impact instability of the roadway support system caused by the collapse of the overlying hard roof strata during the coal mining process, and to guide the prevention and control of mine rock burst disasters, taking I010203 working face of Kuangou Coal Mine as the background, Abaqus numerical analysis software was used and a refined model was established to simulate and analyze the support system of the hard roof roadway under the combined action of dynamic and static loads, the propagation process of dynamic loads, as well as the dynamic response characteristics of roadway surrounding rock under the combined action of dynamic and static loads, are also analyzed. The anti-impact capacity was evaluated on the basis of checking the anti-impact capacity of the roadway support system. The results show that the current support system can effectively resist the impact loads generated by previous large-energy events.

To explore the analysis on application effect and prognostic factors of medical care combined with nursing in the elderly with type 2 diabetes mellitus (T2DM) and cerebral infraction (CI) based on targeted management mode. The clinical data of 180 elderly patients with T2DM and CI in our hospital from August 2017 to August 2019 were selected for retrospective analysis. Their cognitive function and daily living ability before and after intervention were evaluated, using the National Institutes of Health Stroke Scale (NIHSS) to evaluate their prognosis. They were divided into good prognosis group (n = 134) and poor prognosis group (n = 46) according to the score. Binary Logistic regression analysis was adopted to analyze the prognostic factors of such patients. After intervention, patients had visibly lower indexes of blood glucose fluctuation and lower average scores of ADL and MMSE (P < 0.001), with differences in body mass index, systolic pressure, diastolic pressure, fasting blood glucose and triglyceride in both groups (P < 0.001). Binary Logistic regression analysis showed that systolic pressure, diastolic pressure and triglyceride were risk factors affecting patients' prognosis (P < 0.05). Medical care combined with nursing based on targeted management mode has a remarkable control effect on blood glucose, and has a positive effect on improving cognitive function and living ability of elderly patients with T2DM and CI. In addition, attention should be paid to monitoring systolic and diastolic blood pressures, and triglyceride in patients to improve the prognosis. [ABSTRACT FROM AUTHOR]

ABSTRACT During the mining process, repetitive stress disturbances induced by mining activities can lead to alterations in the physical properties of coal, potentially resulting in rockburst occurrences within tunnels. To investigate the propagation rule of physical field characteristics and characteristics of failure in roadway surrounding rock under multiple disturbance damage caused by dynamic load, a combined experimental and theoretical analysis is conducted to study the weakening effect of rock mass under various disturbance circumstances. A model of roadway surrounding rock loosening and failure under multiple disturbances was proposed. The degree of damage is quantified by defining the weakening coefficient Di, A “weakening variable method” is proposed to confirm the main parameters of the Holmquist‐John‐son‐Cook (HJC) model under different disturbance conditions. The reliability of these findings was validated through a microseismic event at the Tangshan coal mine's 0250 working face in 2020, followed by numerical simulation studies. The results indicate that damaged coal weakens the intensity of stress waves at the same source velocity, with the strongest effect observed at interfaces between different damage zones. Furthermore, damaged coal exhibits a stronger weakening effect on stress wave propagation speed compared to undamaged coal in non‐interface areas. The study on roadway stability reveals that severely damaged coal‐rock samples significantly weaken stress waves; however, they also exhibit lower minimum energy for dynamic failure in roadway surrounding rock, indicating that low‐stress waves cause greater damage under severe damage conditions. The study investigates the impact of coal rock mass degradation on the stability of surrounding roadways under various disturbance conditions, which holds significant implications for the timely identification of potential instability risks in damaged coal bodies, optimization of support strategies, and ensuring mining safety. [ABSTRACT FROM AUTHOR]

Range extender hybrid vehicles have the advantages of better dynamics and longer driving range while reducing pollution and fuel consumption. This work focuses on the control strategy of an Auxiliary Power Unit (APU) operating in power generation mode for a range-extender mixer truck. When an operating point is switched, the engine speed and generator torque of the APU will switch accordingly. In order to ensure APU fast and stable adjustment to meet the power demand of the vehicle as well as operate at the lowest fuel consumption, a fuzzy adaptive PID coordination control strategy based on particle swarm optimization (PSO) is proposed to control the APU. The optimal operating curve of APU is calculated by coupling the engine and generator first. Then, the adaptive PID algorithm is used to control the speed and torque of the APU in a dual closed loop. The PSO is used to optimize the PID control parameter. Through hardware-in-the-loop tests under different working conditions, the control strategy is verified to be effective and real-time. The results show that the proposed control strategy can coordinate the operating of engine and generator and control the APU to track target power stably and quickly under minimum fuel consumption. Compared with traditional PID control strategy, the overshoot, regulation time and steady-state error are reduced by 55.1%, 11.1% and 77.3%, respectively. [ABSTRACT FROM AUTHOR]

Tumor‐associated macrophages (TAMs) greatly contribute to immune checkpoint inhibitor (ICI) resistance of cancer. However, its underlying mechanisms and whether TAMs can be promising targets to overcome ICI resistance remain to be unveiled. Through integrative analysis of immune multiomics data and single‐cell RNA‐seq data (iMOS) in lung adenocarcinoma (LUAD), lymphotoxin β receptor (LTBR) is identified as a potential immune checkpoint of TAMs, whose high expression, duplication, and low methylation are correlated with unfavorable prognosis. Immunofluorescence staining shows that the infiltration of LTBR+ TAMs is associated with LUAD stages, immunotherapy failure, and poor prognosis. Mechanistically, LTΒR maintains immunosuppressive activity and M2 phenotype of TAMs by noncanonical nuclear factor kappa B and Wnt/β‐catenin signaling pathways. Macrophage‐specific knockout of LTBR hinders tumor growth and prolongs survival time via blocking TAM immunosuppressive activity and M2 phenotype. Moreover, TAM‐targeted delivery of LTΒR small interfering RNA improves the therapeutic effect of ICI via reversing TAM‐mediated immunosuppression, such as boosting cytotoxic CD8+ T cells and inhibiting granulocytic myeloid‐derived suppressor cells infiltration. Taken together, we bring forth an immune checkpoint discovery pipeline iMOS, identify LTBR as a novel immune checkpoint of TAMs, and propose a new immunotherapy strategy by targeting LTBR+ TAMs. Highlights: Integrative analysis of immune multiomics data and single‐cell RNA‐seq data pipeline is developed and finds lymphotoxin β receptor (LTBR) expression specific in tumor‐associated macrophages (TAMs).LTΒR+ TAMs correlate with lung adenocarcinoma stages, immunotherapy resistance, and prognosis.LTΒR maintains TAM immunosuppressive activity and M2 phenotype by noncanonical nuclear factor kappa B signaling and Wnt/β‐catenin signaling.Disruption of LTΒR in TAMs enhances the therapeutic effect of cancer immunotherapy. [ABSTRACT FROM AUTHOR]

In view of the problem that it is difficult to accurately determine the maximum subsidence value of the surface of the fully mechanized caving face, according to the characteristics of movement, deformation and damage of overburden in goaf and the law of mine pressure appearance, it is proposed that the height of the remaining free space of the overburden is equal to the maximum subsidence of the surface. Through the analysis of the spatial transformation relationship between the residual free space height of overburden and the mining height, the height of caving zone and the residual swelling height of caving rock mass, the calculation model of the maximum subsidence value of the working face to be mined is established. Taking the S2S2 working face of Daping Mine as an example, the maximum subsidence value of the surface obtained by the calculation model is 11.17 m, and the maximum subsidence value obtained by the actual measurement is 11.07 m. The relative error between the calculation result and the actual measurement result is 0.10 m, and the error rate is only 0.90%.

Genetic and environmental factors influence the growth and quality of medicinal plants. In recent years, rhizosphere microorganisms have also emerged as significant factors affecting the quality of medicinal plants. This study aimed to identify Schisandra resources with high lignan content and analyze the microbial diversity of the rhizosphere soil. High-performance liquid chromatography was used to measure the lignan content in nine Schisandra fruits. High-throughput sequencing was used to analyze the 16S rDNA sequences of rhizosphere bacteria to identify bacterial species diversity. The total lignan content of the nine Schisandra resources ranged from 9.726 mg/g to 14.031 mg/g, with ZJ27 having the highest content and ZJ25 the lowest. Among the six lignan components, Schisandrol A had the highest content, ranging from 5.133 mg/g to 6.345 mg/g, with a significant difference between ZJ25, ZJ27, and other resources (p < 0.05). Schizandrin C had the lowest content, ranging from 0.062 mg/g to 0.419 mg/g, with more significant differences among the resources. A total of 903,933 sequences were obtained from the rhizosphere soil of the nine Schisandra resources, clustered into 10,437 OTUs at a 97% similarity level. The dominant bacterial phyla were Actinobacteriota, Acidobacteriota, Proteobacteria, Chloroflexi, Gemmatimonadota, and Verrucomicrobiota. The dominant bacterial genera were Candidatus_Udaeobacter, Candidatus_Solibacter, RB41, Bradyrhizobium, Gaiella, and Arthrobacter. ZJ27 is the Schisandra resource with the highest lignan content, and the rhizosphere bacteria of Schisandra are rich in diversity. Schisandra B is negatively correlated with Bryobacter, Candidatus_Solibacter, and unnamed genera of Gaiellales. [ABSTRACT FROM AUTHOR]

In order to analyze the development law of overlying strata fracture zone in filling mining, the fracture mechanics process of key strata in filling mining was analyzed by using the theory of plate and shell. It is found that the water-conducting fault zone develops layer by layer with the increase of mining thickness, rather than progressive development with the increase of mining thickness. The numerical simulation method is used to reproduce the development law of overlying rock fracture zone at different filling heights after mining. It is concluded that the development of overlying rock “two zones” has a critical effect with the change of equivalent mining height, that is, the quantitative change of filling height will cause the qualitative change of the deformation and failure height of overlying rock. The development of overlying strata fracture zone after mining in filling working face is observed. The measured results are in agreement with the theoretical analysis results. The measured results verify the conclusions of the theoretical analysis and numerical simulation.

In view of the problems of small dam structure, large buried depth of coal seam and large ratio of dam structure height to buried depth of coal seam, it is difficult to calculate the movement and deformation law of dam structure by conventional methods. It is proposed to separate the movement and deformation of the surface and the dam structure, quantitatively analyze the movement and deformation of the dam structure under the surface movement and deformation, obtain the movement and deformation law of the dam structure with different advancing lengths of the working face, and establish the space-time sequence inversion mechanism of local amplification of the dam structure in deep coal seam mining under the dam. Taking the mining of the working face under the dam of a mine as an example, the research results show that the maximum subsidence value of the dam body obtained by numerical simulation is 7.17 m, and the absolute error is 0.093 m compared with the measured result of 7.077 m.

SO2 plays an important role in wine fermentation, and its effects on wine aroma are complex and diverse. In order to investigate the effects of different SO2 additions on the fermentation process, quality, and flavor of 'Beibinghong' ice wine, we fermented 'Beibinghong' picked in 2019. We examined the fermentation rate, basic physicochemical properties, and volatile aroma compound concentrations of 'Beibinghong' ice wine under different SO2 additions and constructed a fingerprint of volatile compounds in ice wine. The results showed that 44 typical volatile compounds in 'Beibinghong' ice wine were identified and quantified. The OAV and VIP values were calculated using the threshold values of each volatile compound, and t the effect of SO2 on the volatile compounds of 'Beibinghong' ice wine might be related to five aroma compounds: ethyl butyrate, ethyl propionate, ethyl 3-methyl butyrate-M, ethyl 3-methyl butyrate-D, and 3-methyl butyraldehyde. Tasting of 'Beibinghong' ice wine at different SO2 additions revealed that the overall flavor of 'Beibinghong' ice wine was the highest at an SO2 addition level of 30 mg/L. An SO2 addition level of 30 mg/L was the optimal addition level. The results of this study are of great significance for understanding the effect of SO2 on the fermentation of 'Beibinghong' ice wine. [ABSTRACT FROM AUTHOR]

By using the multi-shift transmission system,the drivability and economy of electric bus could be improved,the requirement of motor performance is reduced and the diving range is extended. The AMT control strategy model of electric bus is built,the shifting control strategy is developed and the shifting schedule is optimized. By analyzing the motor characteristics,as well as the clutch performance evaluation in the process of starting and shifting,a control strategy of motor and clutch is developed based on Matlab / Simulink. A simulation model is built based on Cruise and shift schedules based on the principle of best power performance and best economy performance. The simulation result indicated that the control strategy is able to make the motor work in high efficient area and improve the operation efficiency of the motor.