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Objective To investigate the treatment methods and efficacy of acute pulmonary embolism. Methods The diagnosis and treatment information of 8 patients with APE secondary to pelvic vein thrombosis admitted by the Changsha First Hospital from 2020 to 2021 were recorded and analyzed. All patients treated with temporary inferior vena cava filter combined with catheter contact thrombolysis. The prognosis was analyzed after the 3-month follow-up. Results After treatment, Arterial partial pressure of oxygen increased from （52.83±4.18） mmHg to （92.34±6.12） mmHg （t=33.221, P＜0.01）, and blood oxygen saturation increased from (80.83±5.34)% to (96.12±4.11)% （t=13.853, P＜0.01）. The shock index and Miller's score significantly decreased. All patients recovered and were discharged, with an average hospital stay of 17.5 days. The recovery rate of the temporary inferior vena cava filter was 100%, with an average recovery time of 3.38 weeks. After 3 months, pulmonary artery CTA showed a 100% patency rate of the pulmonary artery tunk. Conclusion The combination of temporary inferior vena cava filter and catheter contact thrombolysis is a safe and effective treatment for acute pulmonary embolism secondary to pelvic vein thrombosis.

Objective To determine the best collection time period of plasma which can be used for human COVID-19 immunoglobulin for intravenous injection through SARS-CoV-2-IgG change and neutralizing antibody distribution against different virus strain in representative mixed plasma before and after Omicron strain infection by ELISA and pseudovirus neutralization test. Methods An ELISA method for quantitative detection of SARS-CoV-2-IgG was established and its linear range,accuracy and precision was verified. SARS-CoV-2-IgG potency was detected in 25 convalescent plasma which were collected 20-40 days after confirmed Omicron infection, two groups of mixed plasma samples WP1 and WP2 were prepared according to the SARS-CoV-2-IgG results, and pseudovirus neutralization experiments with different virus strain (prototype strain, BA. 1,BA.2, BA.4/5, BF.7, BQ.1.1) were carried out to determine the distribution of neutralizing antibodies against different virus strain. SARS-CoV-2-IgG potency of representative mixed plasma collected from 14 plasma stations subordinate to the company before and after Omicron strain infection was detected, including Omicron convalescent plasma (OP) collected from different plasma stations from December 2022 to May 2023 and normal pool plasma (VN) feed in March 2023 which collected from March 2022 to December 2022. According to the results, the difference and the change rule with time of SARS-CoV-2-IgG before and after Omicron strain infection were analyzed. Results The linearity of SARS-CoV-2-IgG ranged from 6.25 to 200 EIU/mL, the accuracy in-batch ranged from 81.793% to 106.985%, the precision in-batch ranged from 1. 100% to 13.000%, and the total error in-batch ranged from 2.988% to 22.679%. The accuracy between batches ranged from 90.788%to 96.893%, the precision between batches ranged from 4.870% to 6.272%, and the total error between batches ranged from 9.192% to 15.399%. The results of pseudovirus neutralizing antibody showed that the potency of different virus strain neutralizing antibodies were in the order of prototype strain>BA.2>BA.4/5>BF.7≈ BQ.1.1>BA.1 and the correlation between WP1 and WP2 was high (Pearson r=0. 931 1, P=0.002 3) which indicated that the potency distribution of neutralizing antibodies of different virus strain in Omicron convalescent plasma was basically stable. Compared with the mixed convalescent plasma sample G128 collected in June 2022, the potency of Omicron neutralizing antibodies of WP series were significantly higher, the ratio of BA.2 antibody to prototype antibody increased from 26.9% (before infection) to 82.6%-87.5% (after infection). The results of VN series before Omicron infection were < 100 EIU/mL, and the results of OP series after Omicron infection showed that the plasma collected from the beginning of December 2022 was the peak of antibody in the same month,and then dropped sharply, entering a short plateau in February-March 2023 (potency was about 40% of the peak value),and then dropped sharply again in April (potency was about 20% of the peak value). Conclusion The potency and proportion of neutralizing antibody against Omicron subtype in convalescent plasma after COVID-19 Omicron strain infection increased significantly. IgG antibody of plasma donors in different regions reached its peak in the month of infection, then continued to dropped sharply. The best collection period of plasma that can be used for human COVID-19 immunoglobulin for intravenous injection was 1 to 2 months after infection.

Parathyroid hormone type 1 receptor (PTH1R), a member of the G-protein-coupled receptor family, is extensively expressed in the human body and is involved in various processes such as embryonic development, calcium and phosphorus homeostasis, body metabolism and tumorigenesis. PTH1R is highly expressed in the kidney, and its activation is involved in the development and progression of renal diseases though multiple mechanisms and complicated pathways, and is closely associated with a variety of renal diseases such as diabetic nephropathy, glomerulonephritis, acute kidney injury, and chronic kidney disease. This article reviews recent studies about the function of PTH1R, and its role and mechanism of action in renal diseases, and provides an in-depth discussion on the relationship and related mechanisms between PTH1R and kidney diseases, offering new ideas for the diagnosis and treatment of kidney diseases.

Objective To determine the ELISA kit for screening convalescence plasma with high potency of SARS-CoV-2 IgG by comparing and analyzing the plasma detection results of convalescent plasma collected in different periods via ELISA kits from two manufacturers and the results of mixed plasma with different potency via pseudovirus neutralization experiments. Methods Two ELISA kits from different manufacturers(named A, B) were used to detect the plasma of 269 convalescent patients collected from Feb.2020~Jan.2022. The correlation and concordance rate of the two results were analyzed to determine the kit preliminarily. According to the titers of diluted series of standard of the preliminary selected kit, 5 mixed plasma samples (G4-G128) with different potency were prepared. The correlation of ELISA IgG results of product A/B, as well as the pseudovirus neutralization test of the original strain, Omicron mutant BA.1 and BA.2 strains were analyzed. Combined with the outside-well dilution mode of the strongly positive samples, the kit for high potency of SARS-CoV-2 IgG screening was determined. Results When the internal control reference B2 was used as the standard, the detection sensitivity of product A and B was 1∶32 vs 1∶8; the detection sensitivity of product A was 4 times that of product B. The correlation Pearson r between the results given by two kits was 0.944 1(PBA.2(0.970)>BA.1(0.799); the order of correlation r between ELISA IgG results of product B and neutralization antibody potency of the three viruses was original strain(0.994)>BA.2(0.968)>BA.1(0.804). If twice-diluted B2 was taken as the excellent standard, 55.4% of product B met the criterion, while 47.2% of product A met.For positive plasma with high IgG potency, the product B kit required a lower dilution of the sample, which was more convenient to operate. Conclusion Both of the ELISA IgG kit from product A and B can be used to screen IgG antibodies of SARS-CoV-2, while product B is more suitable for screening positive plasma with high IgG potency.

Background and objective Among frequently-used tumor markers in lung cancer, carcinoembryonic antigen (CEA) and carbohydrate antigen 125 (CA125), cytokeratin 19 (CYFRA21-1) and squamous carcinoma antigen (SCC), neuron specific enolase (NSE) and pro-gastrin-releasing peptide (ProGRP) are respectively expressed highly in lung adenocarcinoma, lung squamous carcinoma and small cell lung cancer. By comparing patients with multiple increased tumor markers (group A) and patients with increase of CEA and/or CA125 (group B), this study aims to investigate the utility of multiple increased tumor markers in therapeutic evaluation and prediction of disease relapsing in patients with advanced lung adenocarcinoma. Methods Patients with stage IV lung adenocarcinoma who receiving the first line chemotherapy in Cancer Hospital, Chinese Academy of Medical Sciences were enrolled and retrospectively analyzed. Clinical characteristic, serum tumor markers before chemotherapy, efficacy evaluation, progression-free survival (PFS) were analyzed. Results Except CEA and CA125, the highest ratio of increased tumor markersin group A was CYFRA21-1 (93%), then was NSE (36%), SCC (13%) and ProGRP (12%). Patients with multiple increased tumor markers tend to have more distant metastasis (P

In view of unstable problem existed in fault diagnosis result for rolling bearing of shearer based on K-means clustering algorithm, a new fault diagnosis method of rolling bearing of shearer based on TDKM-RBF neural network was proposed. The method adopts Tree Distribution algorithm to determine initial clustering center of the K-means clustering algorithm, so as to eliminate volatility of K-means clustering results. The method uses K-means algorithm to determine the parameters of the RBF neural network, then the trained neural network was used for fault diagnosis. The simulation results show that the method has quick clustering process,higher steability, and obviously improves accuracy of fault diagnosis for rolling bearing of shearer.

Anodic oxidation processes of 2198 and 5A90 Al-Li alloys were carried out with pulse-current (PC) in the mixture of acid solution of 18%(mass fraction,the same below)H2SO4+5%C2H2O4 at room temperature. Surface and cross-sectional morphologies and composition distributions of anodic oxidation films were observed and determined by scanning electron microscope equipped with energy disperse spectroscopy (SEM/EDS). The corrosion resistances of these films were assessed by means of 10%NaOH aqueous solution dropping test and potentiodynamic polarization plot in 3.5% NaCl solution. The results show that the oxidation films of 2198 and 5A90 Al-Li alloys are mainly composed of Al oxides. For 2198 Al-Li alloy, fine and small particles evenly distribute in the oxidation film; and the film thickness is about 150 μm. For 5A90 Al-Li alloy, micro-pores existing in the film can provide better structure for later sealing; and the film thickness is nearly 180 μm. The larger thickness oxidation films of both two kinds of alloys prepared by pulse current anodic oxidation treatment have superior corrosion resistance in 3.5%NaCl solution.

Background and objective Amorphigenin, a rotenoid compouns, from seeds of Amorpha fruticosa, has been shown to possess anti-proliferation activities in several cancer cells. To explore the antitumor effects of amorphigenin on cisplatin-resistant human lung adenocarcinoma A549/DDP cells and explore the underlying mechanisms. Methods CCK-8 assay was used to measure the proliferation of A549/DDP cells; Colony formation assay was used to measure the colony formation of A549/DDP cells; Flow cytometry assay was used to detect the apoptosis rates; Western blot analysis was used to explore the expression of apoptosis-related proteins (caspase-3 protein, PARP protein) and lung resistance protein (LRP). Results Our results demonstrated that amorphigenin could inhibit the proliferation of A549/DDP cells with a inhibition concentration of 50% cell growth (IC50) at 48 h of (2.19±0.92) μmol/L. Amorphigenin could inhibit the colony formation ability and induce apoptosis of A549/DDP cells; Furthermore, amorphigenin combined with cisplatin showed synergistic proliferation-inhibitory effect and apoptosis-promoting effect in A549/DDP cells; reduced the expression of LRP of A549/DDP cells. Conclusion Amorphigenin remarkably inhibits the proliferation and induces apoptosis in A549/DDP cells. Combination of amorphigenin with cisplatin had the synergistic inhibitory effect on A549/DDP cells by downregulating the expression of LRP.

Background and objective Small cell lung cancer (SCLC) is a rapidly growing tumor with characteristic of neuroendocrine cellular function. Neuron specific enolase (NSE), pro-gastrin-releasing peptide (ProGRP) and lactic dehydrogenase (LDH) are valuable in diagnosis and treatment of SCLC. By analyzing the variation of NSE, ProGRP and LDH before and after treatment, the aim of this study is to investigate the efficacy of tumor markers in diagnostic staging, therapeutic evaluation and prediction of disease relapsing. Methods Patients with SCLC who receiving the first line chemotherapy in Cancer Hospital, Chinese Academy of Medical Sciences were enrolled and retrospectively analyzed. Clinical characteristic (includes NSE, ProGRP and LDH level before and after 2 cycles chemotherapy), efficacy evaluation, progression-free survival (PFS) were analyzed. Results Before treatment, Serum NSE, ProGRP and LDH in patients with extensive disease (ED) were significantly higher than those with limited disease (LD)(all P4 cycles chemotherapy and with obvious decrease of ProGRP than those who accepted ≤4 cycles chemotherapy and with less obvious decrease of ProGRP in LD group; ED patients with no more than 2 distant metastasis, normal LDH level before treatment and obvious decrease of ProGRP after chemotherapy had lower short term relapse risk. In addition, the types of relapse (sensitive relapse, drug resistance relapse and refractory relapse) were negatively correlated with decrease of ProGRP (P=0.044). By multivariate analysis, numbers of chemotherapy cycle was independent prognostic factor for PFS in LD SCLC; numbers of distant metastasis and decrease of ProGRP were independent prognostic factors for PFS in ED SCLC. Conclusion Increase level of serum tumor markers is related to tumor burden. Decrease level of ProGRP after treatment may prognose efficacy and relapse risk.

For problems that traditional chopping current protection circuit had small cut-off current value and poor anti load impact ability, and needed additional recovery circuit or manual circuit after over-current fault, a novel chopping current protection circuit for intrinsically safe power supply was designed. The circuit adopts double parallel control structure, so as to improve reliability. The circuit can chop circuit rapidly under condition of load over flowing, and put into operation fast after fault with adjusted input point. Meanwhile, the circuit has low power consumption part, so as to reduce power loss under condition of light load or no-load. The experimental results show that the circuit can recover automatically after over-current fault with low load effect and strong load capacity.

The structure, principle, technical characteristics and existed problems of traditional gangue blocking device of shearer with large mining height were analyzed, an improvement design was proposed and simulation analysis was given. By means of increasing cylinder number, strengthening and thickening top guard, changing rigid connection to flexible connection and adding flow dividing and combining valves, dynamic adjustment and bracing of the guard are achieved, and reliability of gangue blocking device and mining efficiency of shearer are both improved. The simulation result shows that the force of the improved gangue blocking device is more even, and the guard can withstand greater force.

Considering the effects of time-varying load, time-varying excitation, longitudinal stiffness, radial stiffness and bending stiffness of each pulley, the dynamic analysis model of the inner and outer engine front-end accessory drive system is established by Simdrive software. The static characteristics of the system are evaluated. Galerkin method is used to discretize the system space, the implicit multi-step method is used to solve the dynamic characteristics of the system under acceleration conditions, and the influencing factors of the accessory pulley speed fluctuation, tension fluctuation and belt-pulley slip characteristics are obtained. Based on the analysis results, an improvement plan is proposed to appropriately increase the initial tension and the crankshaft wheel wrap angle, and add an automatic tensioner at the No.2 idler gear. The comparison analysis shows that the dynamic characteristics of the engine front-end accessory drive system are improved effectively when adding automatic tensioner.

A scorpion like robot is designed for temperature measurement of coke ovens in response to the harsh environment on the top of the coke oven, low accuracy and efficiency of manual temperature measurement. This study mainly analyzes the design based on the robot's leg walking mechanism. Firstly, the biomimetic structure of the scorpion is referred to complete the modeling of the overall structure of the coke oven temperature measuring robot and the design of its legs. Stress analysis indicates that it operates safely and stably during the temperature measurement process. Then the D-H coordinate system of the robot's kinematic structure is established, and the forward and inverse kinematics of its legs are analyzed. Then, Matlab is used to plan the Cartesian space trajectory of the legs and Adams is used to simulate the gait of the leg joints, indicating that the motion curves of the leg trajectory planning and gait simulation are almost identical and running smoothly. The experiment shows that the actual error of the temperature measurement robot's movement is maintained within 2 mm and runs smoothly. This lays an important foundation for the development of the overall system of the coke oven temperature measurement robot in the future.

To investigate the regulation effect of polyaspartic acid-chitosan (PAC) on photosynthetic characteristics and yield of spring foxtail millet, this experiment was conducted using foxtail millet varieties of Zhangzagu 13 (Z13) and Huayougu 9 (H9) in Gongzhuling Experimental Station of Chinese Academy of Agricultural Sciences (43º29'55"N, 124º48'43"E) in 2020 and 2021. Conventional fertilization (CN) and PAC with fertilization (PN) treatments were set under six nitrogen fertilizer application levels of 0, 75, 112.5, 150, 225, and 337.5 kg hm-2. The results showed that the photosynthetic rate, SPAD value and soluble protein content of flag leaf, net assimilation rate, leaf area duration, and crop growth rate of foxtail millet of two varieties increased first and then decreased with the increase of nitrogen application. PN could increase SPAD value and soluble protein content of flag leaf at post anthesis stage and photosynthetic rate of flag leaf at anthesis and mid-filling stage under the same nitrogen application level. Meanwhile, the net assimilation rate, leaf area duration, and crop growth rate of foxtail millet were also increased, which promoting the accumulation of population photosynthate. The increase effect of the items above was more significant under the low-middle nitrogen application levels of 75, 112.5, and 150 kg hm-2 . Compared with CN, the yield of Z13 increased by 11.24%--21.55% and 8.65%--14.22% in 2020 and 2021, respectively. The yield of H9 increased by 5.53%--15.75% and 10.43%--16.17% in 2020 and 2021, respectively, compared with CN. Correlation analysis indicated that the yield was significantly positively correlated with net assimilation rate, leaf area duration, crop growth rate, and photosynthetic rate. In conclusion, PAC combined with nitrogen fertilizer could increase the ability to photosynthesize and grain yield under the background of one-time basic fertilizer application, which could be an important technique for achieving high grain yield and efficiency in foxtail millet production in China. [ABSTRACT FROM AUTHOR]

Objective: To explore the mechanism and clinical significance of carboxypeptidase A4 (CPA4) promoting the proliferation, migration, invasion and epithelial-mesenchymal transformation (EMT) progression of non-small cell lung cancer (NSCLC) cells. Methods: IHC and WB were employed to detect the expression of CPA4 in NSCLC tissues and adjacent tissues of 105 patients with advanced or metastatic NSCLC in Jinan Central Hospital from February 2012 to December 2015 and the expression of CPA4 in NSCLC cells. Chi-square test was used to analyze the association between CPA4 expression and the clinicopathological characteristics of the patients. The relationship between CPA4 expression and the overall survival (OS) of the patients was analyzed by Kaplan-Meier method. H1299 and A549 NSCLC cells with stable overexpression and downexpression of CPA4 were constructed by cell transfection. Changes in the cell proliferation, invasion and migration after overexpression and knockdown of CPA4 were detected by CCK-8 assay, cell colony formation assay, scratch healing assay and Transwell assay. Xenograft tumor models and tail vein-lung metastasis tumor models of nude mice were established to detect the role of CPA4 in tumor tumorigenesis and metastasis in vivo. Changes in the markers of EMT in the tissues of xenografts were detected by WB and IHC. Results: Compared with paracancer tissues and normal lung epithelial cells, CPA4 was highly expressed in cancer tissues and cancer cells (all P<0.05). The OS of NSCLC patients with high CPA4 expression was significantly shorter than that of patients with low CPA4 expression (P<0.05). High expression of CPA4 was more common in poor differentiation, N2-3 lymph node involvement and TNM stage IV (P<0.05 or P<0.01). Overexpression of CPA4 promoted H1299 cells, while knockdown of CPA4 inhibited the proliferation, migration and invasion of A549 cells. Overexpression of CPA4 promoted the growth of H1299 cell xenograft tumors and lung metastatic tumors in nude mice. Overexpression of CPA4 promoted the changes of EMT process-related molecules in H1299 cells. Conclusion: CPA4 is highly expressed in NSCLC tissues and cells. Overexpression of CPA4 can induce EMT, promote the proliferation, migration and invasion of NSCLC cells and is related to tumor progression and prognosis. CPA4 is a potential biomarker for predicting relapse and prognosis of NSCLC and can be used for targeted therapy. [ABSTRACT FROM AUTHOR]

The grid-forming （GFM） control technology is instrumental in enabling converters to provide frequency and voltage support response akin to synchronous generators， thus bolstering the stability of the new power system. Nonetheless， a notable challenge lies in delivering grid support during fault current limiting. To this end， a strategy for fault current limiting in GFM converters based on measuring terminal and internal differential voltage orientation is proposed. In this approach， the angles of the positive and negative sequence current commands lag 90° behind the positive and negative sequence voltage differences. Additionally， the maximum magnitude of the synthesized vector of the current commands aligns with the converter’s overcurrent capability， which is equivalent to the generation of positive and negative sequence adaptive virtual inductance by control， respectively. This method obviates the need for direct virtual inductance value calculations and can maximize the maximum support capacity of the converter to realize the fault current characteristics resembling those of synchronous generators. The proposed fault current limiting strategy is validated by a simulation system built through PSCAD/EMTDC. The simulation outcomes affirm the strategy’s efficacy in delivering substantial grid support to the AC system while limiting fault currents.

It is of great importance to explore the effects of saline-water furrow irrigation on soil water-stable aggregates for safe and efficient utilization of saline water resources. We conducted a long-term cotton experiment with six levels of saline-water furrow irrigation (1, 2, 4, 6, 8, 10 g · L-1) since 2006 and analyzed the variations of soil salinity and water-stable aggregates in the 10th and 15th years under saline irrigation. The results showed that soil salinity in the 0-30 cm layer at the ditch increased with increasing salinity level of irrigation water. There were significant differences between the 6, 8, 10 g · L-1 and 1 g · L-1 treatments. Soil salinity in each treatment increased gradually with increasing soil depth. Saline-water furrow irrigation tended to reduce the stability of soil water-stable aggregates. When the salinity level of the irrigation water was ≥ 6 g · L-1, the mass fraction of macroaggregates (>0.25 mm), the mean weight diameter and geometric mean diameter of water-stable aggregates significantly decreased. In contrast, the fractal dimension and mean weight specific surface area increased significantly. The stability of soil water-stable aggregates decreased with soil depth in all treatments. Under the condition of saline-water furrow irrigation for several years, there was no accumulation of soil salinity and instability of water-stable aggre-gates in the 0-30 cm soil layer at the ditch with each passing year. With the irrigation scheduling of this study, saline-water furrow irrigation with salinity ≤ g · L-1 did not affect soil salinity and water-stable aggregate stability of cotton field in this area. [ABSTRACT FROM AUTHOR]

The surface of the glass fiber has been modified by impregnation process, and the glass fiber reinforced nylon 6 composites has been prepared. The effect of the mass fraction of cyanoethyltriethoxysilane in the glass fiber impregnating solution on the mechanical properties of composites is studied, and it is compared with γ - aminopropyltriethoxysilane (KH 550) and γ - (2,3 - epoxy propoxy) propyltrimethoxysilane (KH 560). The results show that as the mass fraction of cyanoethyltriethoxysilane increases in the glass fiber impregnation solution, the mass loss rate of the treated glass fiber and the mechanical properties of the composites first increase and then decrease. The preferred cyanoethyltriethoxysilane has mass fraction of 1. 0% in the impregnation solution, and the treated glass fiber has 3% the mass loss rate, the cyanoethyltriethoxysilane on the glass fiber has a better grafting rate. The notched impact strength, tensile strength and flexural modulus of the composites reach the maximum value, 4.4 MPa, 78.9 MPa and 3 580 MPa respectively. Compare to those prepared with unmodified glass fiber, its ratios increases by 57.14%, 17.01% and 5.89% respectively. On improving the impact strength of composites, cyanoethyltriethoxysilane has the same effect as KH 550, and both are better than KH 560. On improving the tensile strength and flexural modulus of the composites, cyanoethyltriethoxysilane is better than KH 550. [ABSTRACT FROM AUTHOR]

The traditional monitoring methods for coal mine roadway deformation have problems such as incomplete data collection, non intuitive data format, poor precision, and inability to achieve continuous monitoring of the entire roadway deformation. In order to solve the above problems, a deformation monitoring method for coal mine roadway based on 3D laser scanning is proposed. Firstly, the method uses 3D laser scanning technology to obtain real 3D point cloud data of coal mine roadways. Secondly, the deep learning model VoxelNet is used to detect and denoise 3D laser scanning data, converting unordered point cloud data into high-dimensional feature data. The Alphashape algorithm is used to fit the discrete points of the extracted roadway cross-section. The multi-dimensional difference calculation based on the difference method is used to obtain specific data of roadway deformation, achieving full coverage of roadway deformation monitoring in the mining area. The 3D laser scanning technology is applied to deformation monitoring of the 30507 working face in Tashan Coal Mine. The cross-sectional analysis and 3D overall analysis are conducted on the 3D point cloud data of the roadway. The analysis results indicate that the main deformation in the area can be directly observed through the relative deviation of the section contour of the second stage roadway. If the upper contour deviates inward, the roof will collapse. If the lower contour deviates outward, the floor will bulge. As the distance between the measuring point and the working face gets closer, the color of the attached color model leans towards red and blue. The darker the color, the greater the deformation of the roadway.

With the popularity of smart devices such as stnartphones and pads, the attack of Android ransomware is becoming increasingly serious. Compared with other malicious software, ransomware is widely favored by hackers because of hard restoration and the directness of obtaining benefits, which also brings serious spiritual and property damage to users. To protect our smart devices from ransomware and reduce threats and losses, researchers conduct a lot of research on Android ransomware and propose many practical detection schemes. This paper first summarizes the characteristics of Android ransomware, and then summarizes the existing research work on detecting and safeguarding against ransomware on the Android platform and makes a comprehensive analysis and comparison on them. Finally, we point out the remaining problems of these solutions, put forward corresponding suggestions and discuss future research directions. [ABSTRACT FROM AUTHOR]

When the extra thick coal seam is mined in the goaf, the remaining coal pillar of upper coal seam and adjacent working face will have an important impact on the stability of mining roadway. At present, the research on deformation and failure mechanism and control of mining roadway does not consider the complex environment of gob-side roadway in extra thick coal seam under the condition of short distance coal pillar mining. In order to solve the problem, taking the 30503 repaired roadway in Tashan Coal Mine as the engineering background, the deformation and failure mechanism of the roadway is analyzed by using the methods of field monitoring, theoretical analysis and numerical simulation. And the corresponding surrounding rock support technology is proposed. A roof separator is arranged on the roof of 30503 repaired roadway to monitor and record the rock displacement at each position of the roof in real time. The monitoring results show that the surrounding rock in the roof of 30503 repaired roadway has been broken due to the impact of adjacent working face and the short distance to the overlying remaining coal pillar. After the roadway excavation, the roof deformation speed is fast, the seperation volume increases continuously and the impact range is wide. According to the monitoring results, the impact of the remaining coal pillar on the deformation and failure of the roadway and the impact of the fracture position of the basic roof on the deformation and failure of the roadway are analyzed. The results show the following points. ① The unreasonable arrangement of the roadway is an important reason for the damage of the repaired roadway. At the same time, in order to avoid the impact of the remaining coal pillar, the roadway is arranged at a distance of more than 35 m from the center of the coal pillar (25 m from the edge of the coal pillar). ② The excavation position of repaired roadway is seriously affected by the remaining coal pillar, and the roadway is in the high stress concentration area before excavation. When the adjacent 30501 working face is mined, the basic roof breaking position is located above the roof of the repaired roadway, which is the direct cause of the broken roof of the roadway. According to the above analysis results, the numerical simulation analysis is carried out on the evolution law of deviatoric stress distribution of coal pillars with different widths, and the targeted technical scheme of surrounding rock stability control is proposed. ① On the premise of ensuring sufficient safety of the coal pillar and avoiding waste of resources, the width of the coal pillar in the 30503 repaired roadway section is set to 8 m. ② When excavating the gob-side roadway in the short distance extra thick coal seam, hydraulic fracturing measures are adopted to reduce the impact of the overlying coal pillars on the coal seam. ③ The support scheme of bolt-mesh-anchor+guniting+single pillar is selected to support the newly excavated roadway. In order to verify the application effect of the surrounding rock stability control technology, the cross observation method is used to continuously monitor the roadway deformation during the excavation of the new repaired roadway in 30503 working face. The results show that the deformation of the two sides is 90 mm, the deformation of the roof and floor is 331 mm, and the deformation of the surrounding rock is effectively controlled.

Low-energy electron beam is an advanced technology that is widely used for manufacturing various high-tech products in the United States, Japan and developed countries in Europe since the 1980s. Owing to the high price of imported electron beam equipment and related processes and raw materials, the promotion of low-energy electron beam technology in China is restricted. In recent years, with the rapid progress in the domestic independent research and development of low-energy electron beam equipment technology, the entry threshold of the downstream industry has been reduced; research conducted by domestic enterprises on new materials, new technologies, and new processes has been extensively promoted, and the bottleneck of industrial development has been broken. Lowenergy electron beam and its application usher in rapid development.

By detecting and identifying the vanishing point position in the image, it is able to assist mobile robots in mines roadways for autonomous navigation. The existing vanishing point detection methods have large errors in the mine roadway with poor lighting conditions and insufficient structured information. In order to solve the above problems, a vanishing point detection method in complex environment of mine roadways is proposed. Firstly, the image is pre-processed by reducing, filtering, graying, etc. This method can reduce the calculation amount significantly and the straight line characteristics can be better preserved. Then, the straight line detection algorithm is used to detect the straight line of the image. The straight line length threshold and the average gradient constraint are introduced to eliminate the interference line with small length and the interference line generated by shadows in the image respectively. Moreover, the block matching algorithm is used to generate the block motion trajectory straight line of the image. Finally, the straight lines after removing the interference and the block motion trajectory straight lines are converted into sample points in the parameter space. The outlier factor value of each sample point is calculated by the local anomaly factor algorithm, and the outlier factor value of the sample point and the length of the corresponding straight line are used as the criteria to measure the importance of the sample points. On this basis, the weight function of the weighted regression algorithm is designed to obtain the best estimate of the vanishing point. The experimental results on the mine roadway data set and public data set show that compared with the edge-based vanishing point detection method and the deep learning-based vanishing point detection method, the method in this paper has stronger robustness to light changes. It has higher accuracy in complex environment with poor lighting conditions and lack of straight line information, and has better real-time performance than the vanishing point detection method based on deep learning. This method can better meet the needs of mine roadway robot navigation.

With litter bag methods, we examined mass loss rates and different chemical fractions of litters from two wetland plant species, Zizania caduciflora and Hippuris vulgaris. Those two species examined here varied significantly in their initial litter chemical traits. Experiment was performed under simulated rising temperature (1.5-2.0 °C), and under three different habitats (air, air-water interface and water soil interface). The results showed that, during one year decomposition period, the mass residual rates exhibited distinct seasonal dynamics, and there were strong interactive effects between seasonal dynamics and environmental factors. Different factors contributed differently for the variation of litter decomposition, 28.8% of which being explained by litter quality, 6.3% of which being explained by rising temperature, and 34.9% being explained by habitat. Along with the decomposition, the contents of different chemical fractions (easy or hard to decompose) varied greatly. Among them, nitrogen contents in H. vulgaris decreased by 53.1%, while the lignin contents increased by 45.4%. Overall, habitat was the most important factor driving litter decomposition, the second was litter quality, and rising temperature had minor effect. [ABSTRACT FROM AUTHOR]

Bladder cancer (BC) is a common malignant tumor of the urinary system. Common white light cystoscopy is the most important method in the diagnosis and treatment of BC, but its ability to identify small tumors and residual tumors at surgical sites is limited, so it is urgent to develop new diagnosis and treatment techniques. With the rise of the concept of precision medicine, a group of targeted molecules that can specifically bind to BC at the cellular and molecular levels have been discovered in recent years, and the molecular image and targeted therapy based on them can significantly improve the diagnosis and treatment efficiency of BC, with a great potential for clinical application. Based on the latest progress and the research work of our research group, this paper comprehensively analyzes and systematically summarizes the application of targeted molecular carriers in the diagnosis and treatment of BC.

Objective To explore the mediating effect of psychological stress and resilience on sleep conditions and working stress among the officers and soldiers during major tasks. Methods Psychological stress evaluating test (PSET), perceived stress scale (PSS), Pittsburgh sleep quality index (PSQI), and Connor-Davidson resilience scale (CD-RISC) were used to survey 464 officers and soldiers who took part in major tasks during June 2019 and June 2020. The subjects were assigned into control group (n=136) and somnipathy group (n=328, including light, moderate and severe subgroups) according to their sleep conditions, and also into low-resilience (n=95) or high-resilience (n=369) groups based on their scores of psychological resilience. Logistic regression analysis was employed to analyze the related factors for sleep disorders, and Pearson correlation analysis was adopted to investigate the correlation of psychological stress and resilience with sleep quality as well as severity of working stress, so as to determine the mediating effect of the former 2 factors on the latter 2. Result After 2 and 6 cases were excluded due to incomplete data from the somnipathy and control group respectively, there were finally 456 cases subjected (134 and 322 cases respectively). The age, numbers of violence witnessed, and PSS and PSET scores were older, larger and higher, while the CD-RISC score was lower in the somnipathy group than the control group (P

Because of the Apollo lunar seismic network merely located on the near side of the Moon and the traditional methods failing in the best solutions, several lunar parameters such as load ratio /, crustal thickness bc, subsurface load depth zb, crustal density ρc, lithospheric elastic thickness Te can be solved through lunar gravity/topography admittance with PSO. Results indicate that surface and subsurface load models are rational and all the best solutions of the lunar parameters studied can be simultaneously calculated. It can provide a reference for lunar internal structure research, when such method investigated here applied to lunar geophysical parameters inversion. [ABSTRACT FROM AUTHOR]

According to the conditions of bubble nucleation and onset of significant void, the accurate transformation requirements for defining flow boiling were proposed. And the boiling heat transfer numerical model was established based on the framework of boiling homogeneous flow model. The accuracy of the numerical model was validated using the Robinson experimental data. Then the temperature field of cylinder head was predicted with the model. Compared with the engine measured temperature field, the predicted results of the new boiling numerical model are more close to the actual test temperature. And the maximum error of fire face temperature is less than 7%. [ABSTRACT FROM AUTHOR]