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In this paper, the characteristics of a squall line that occurred in central and northern Zhejiang on 21 July 2022 are analyzed by using S-band dual-polarization radar, X-band phased array radar data, wind retrieval, lightning location and ERA5 reanalysis data. The results show that: The squall line affected the area for up to 6 hours, causing large-scale winds of 8-10 levels along the way. The pressure surge ahead of the strong winds and precipitation at the extremely strong wind station served as a precursor to extreme winds. The squall line occurred under the control of the subtropical high. The dry and cold air at the bottom of the high-level cold vortex invaded, with the high-energy and high humidity in the low-level forming an unstable layer structure, which provided favourable environmental conditions for the generation and maintenance of the squall line. The observation of the S-band dual polarisation radar showed that the evolution of squall lines went through processes such as initiation, merging, growth, maturity, and disappearance. The initial convection was formed in the mesoscale convergence lines in the northwest and east of Hangzhou. Strong storms in the northwest of Hangzhou moved faster than those in the east, leading to the rapid merging and development of the two into squall lines. After the squall line entered the south bank of the Hangzhou Bay, the storm outflow overlapped with the mesoscale convergence centre on the south bank of the Hangzhou Bay, leading to the rapid development of the squall line to its mature stage. In addition, the growth of vertical wind shear was also conducive to the rapid development of the squall line. Strong winds often occurred in areas with dense cloud flashes. The X-band phased array radar could finely detect the vertical structure of strong cells before and after extreme winds occurred. The development of ZDR and KDP columns in mature strong cells represented storm intensification, and the rapid decline of the echo centroid could indicate surface winds. The falling and dragging of precipitation particles intensified the sinking motion, which further enhanced the strong winds. The configuration of inclined upward and downward airflow in strong squall lines ensured that the falling of precipitation particles did not affect the upward airflow, which was beneficial for the development and maintenance of storms. The oblique sinking airflow met the near-surface environmental wind, triggering the development of frontal convection, which was conducive to the propagation of squall lines downstream.

Taking TiCp/Al-5Cu-1.9Mg-0.9Mn composite materials reinforced with 0.27%（volume fraction）TiC particles as the matrix， the effects of different Sm element contents on the microstructure and mechanical properties of the composite material were investigated. The results show that the addition of the Sm element significantly refines the dendritic microstructure and facilitates the dissolution of the second phase during the solid solution treatment. Consequently， an increase in the density of precipitated phases， including T-Al20Cu2Mn3 and S'-Al2CuMg， was observed in the aged microstructure. When the Sm element content is high （0.3%， mass fraction， the same below）， the microstructure exhibits blocky insoluble rare earth-containing compounds. With the addition of the Sm， the composite materials show a gradual increase in yield strength at both room temperature and 250 ℃. However， it will cause a decrease in plasticity. When the Sm element content is 0.3%， the yield strength at room temperature increases from 246 MPa to 310 MPa， and the yield strength at 250 ℃ increases from 191 MPa to 220 MPa. The analysis suggests that the increase in strength is attributed to the microstructural refinement and the increased density of precipitated phases induced by Sm. Conversely， the reduction in plasticity is attributed to the presence of coarse blocky insoluble rare earth compounds cutting through the matrix， leading to the easy generation of crack sources.

China has a wealth of abundant coalbed methane (CBM) resources at great depths. However, the low permeability of these deep coal seams coupled with the challenges posed by high-stress pressure environments, hampers efficient gas extraction. Water jet punching and cavitation in horizontal wells is a new technology for relieving pressure and enhancing the permeability of coal seam over a wide area. Nevertheless, the mechanisms underlying rock breaking and pore formation in deep environment remain to be studied. Because the deep coal seam exists in the geological environment of high ground stress and high stress difference, it is difficult to carry out the physical simulation experiment in the laboratory. Consequently, a numerical model of water jet punching and rock breaking is established based on the viscoelastic-plastic theory and material point method. The model integrates the advantages of the Lagrange and Euler algorithms, proficiently simulating the whole process of momentum exchange, large deformation of coal, rock breaking, fluid erosion and rock carrying and reverse drainage throughout the process of jet rock breaking. Subsequently, based on this numerical model, the mechanism and influencing factors of rock breaking and pore-forming by water jet in deep coal seams are studied, and the conclusions are as follows: ① the shear failure caused by high in-situ stress load in deep coal seams is the leading mechanism of rock breaking, while jet mainly plays the role of erosion and rock carrying and reverse drainage. The tensile failure caused by stress wave generated by water jet collision with coal rock is the leading mechanism of rock breaking when there is no stress load. Due to the strong plasticity of coal rock, water wedge effect is not obvious. ② The high in-situ stress load accelerates the rock breaking process of deep coal seams. The amount of rushed-out coal under high in-situ stress load is higher than that without stress load. Meanwhile, the stress load causes the coal body to move towards the opening direction, resulting in a decrease in cavity volume, but the plastic damage zone is significantly increased compared with that without stress load. ③ The amount of rushed-out coal and the area of plastic damage zone increase with the increase of jet time, but the increase rate gradually slows down. The amount of rushed-out coal and the area of plastic damage zone show a downward trend with the increase of incident angle. The smaller the jet angle, the better the effect of water jet punching and rock breaking. The vertical incidence of jet is not the best way to break rock. ④ The amount of rushed-out coal and the area of plastic damage area increase with the increase of stress difference and the width of coal-rock opening, but the increase of stress difference has little effect on jet rock breaking in deep coal seams. The width of coal seam opening should not be too high, and the rock breaking efficiency of jet can be improved by increasing the width of the opening hole appropriately.

Purposes In this study, a functional resonance imaging adaptation (fMRIa) experiment was conducted to examine the multi-level adaptation mechanism in 16 ROIs of the human brain cortex. Methods Random dot stereograms were defined by horizontal binocular disparity as visual stimuli. And six different adaptation conditions were designed to separate different adaptation sources. Adaptation strengthes were measured as changes in the BOLD signal between adaptation and test periods. Findings ANOVA results show that both the dorsal and ventral pathways exhibit advanced adaptation effects to shape attributes. Additionally, adaptations to average disparity information in the V7 and IPS regions along the dorsal visual pathway exist, indicating that low-level disparity computations in these regions are used to precisely encode the depth structure of 3D shapes, while the ventral pathway is used for shape classification. Conclusions These evidences validate the multi-evel adaptation for stereo-curvature aftereffects. The findings can provide guidance for optimizing the construction of stereoscopic scenes in virtual reality.

Objective Shield tunneling may cause displacement and deformation of the nearby viaduct foundation and reduce its bearing capacity. Therefore, the deformation effect caused by shield tunnel closely side-passing viaduct foundation is studied based on an actual project. Method Relying on the project of Hefei Metro Line 5 in which the shield tunnel passes the pile foundation of the viaduct on the side, a three-dimensional numerical model is established to analyze the horizontal displacement,the longitudinal displacement and the settlement pattern of the pile foundation caused by shield construction. Result & Conclusion The research results show that the horizontal displacement at the pile bottom presents dynamic changes of leaving, approaching and leaving the tunnel. The horizontal displacement of the pile body is similar to a C shape flexture curve. The displacement increases first and then decreases along with the pile depths, and the extreme value is located at the pile depth of 9~10 m. The longitudinal displacement at the pile bottom （parallel to the tunnel axis） shows a bimodal curve. After the shield passing the pile foundation, the pile body undergoes longitudinal deformation in the opposite direction of the excavation. After the shield passing through the pile foundation for 12m and further, the horizontal displacement of the pile body in longitudinal direction rebounds, indicating that the influence of shield tunneling on the longitudinal deformation of the pile foundation is reversible to a certain extent. The settlement of the pile foundation presents a steep trend. The closer the pile foundation at the same side is to the tunnel, the greater the settlement. Moreover, the excavation of the far side tunnel will cause secondary settlement of the pile top. The maximum settlement occurs at the bottom of the No.4 pile foundation, and the settlement value is 4.94 mm.

[Objective] Biochar application can change soil physicochemical properties. The study of the effects of different biochar application methods on soil moisture, temperature and electrical conductivity (EC) distribution, which can provide basis for the scientific management of seasonally frozen soil. [Methods] The effects of different biochar application methods on soil liquid water content, temperature and EC during freezing period were studied by field experiment and long-term observation in black soil region of northeast. Biochar application methods included one-time biochar mixed application of 40 t/hm2(HO), biochar bottom application of 40 t/hm2(HE), and the blank was 0 t/hm2(CK). [Results] Both biochar application methods increased the mean soil liquid water content during the freezing period (p < 0.05), as HO > HE > CK. The application of biochar application significantly increased soil EC throughout the experimental cycle, and the average soil EC increased by 17.73% and 6.89% in the HO and HE treatments, respectively, compared to CK. The two biochar application methods had different effects on the soil temperature. Compared with CK, the mean soil temperature increased by 0.32 ℃ in the HE treatment, while the mean soil temperature decreased by 0.46 ℃ in the HO treatment. In addition, the HE treatment weakened the range of change in soil liquid water, temperature and EC during the freezing period compared to HO and CK treatments. [Conclusion] Both heterogeneous and homogeneous biochar application were beneficial to increase the liquid water content and EC of degraded black soil during freezing period. Especially heterogeneous biochar application was also beneficial to increase the soil temperature of the tillage layer during freezing period, homogeneous biochar application can also reduce the soil freezing during freezing effect during the same period. Both of the two biochar application modes may have an important impact on the soil moisture-salt transport and material transformation process during the freezing period, and even have an important effect on the spring emergence and early growth of crops.

A wearable walking aid for lower limbs is designed, which is mainly used to assist patients with lower limb movement disorders such as stroke hemiplegia to carry out daily walking activities. First of all, based on the analysis of the lower limb motion mechanism, joint structure and the composition of degrees of freedom, the three-dimensional structure model of the lower limb wearable walker is established. The 3D infrared motion capture system is used to collect the gait data of normal people and fit the corresponding joint angle curve. The simplified D-H model of the walker is established, and the kinematics modeling analysis of the walker is carried out. Taking the gait data collected from the motion capture experiment as the simulation driving force, the kinematics simulation verification of the walker is carried out. The results show that the joint angle change curve is basically consistent with the angle curve collected from the experiment, and the angular velocity change curve and the ankle joint centroid position change curve are consistent with the normal human walking law, which verify the rationality of the structure design of the lower limb wearable walker.

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.

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 enhance the water solubility and stability of hydrophobic active substances. Methods: A nano-delivery system of rice protein hydrolysate （RPH）-xanthan gum （XG）-curcumin （Cur） was developed, wherein curcumin served as the delivery object, and the encapsulation efficiency, stability, antioxidant activity, and formation mechanism of the nanoparticles were determined and analyzed. Results: The encapsulation efficiency of RPH-XG-Cur nanoparticles reached 78.40%, with a particle size of 74.78 nm, PDI of 0.36, and Zeta potential of -27.93 mV. Remarkably, the incorporation of xanthan gum significantly improved the encapsulation performance as well as pH and ionic strength stability of the nanoparticles. Fourier infrared and fluorescence spectra analysis revealed that hydrogen bonding, electrostatic interaction, and hydrophobic interaction played crucial roles in nanoparticle formation. Conclusion: RPH-XG nanoparticles exhibit great potential as nanocarriers for delivering hydrophobic bioactive substances.

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.

The hemiplegic patients can't walk on their own due to the movement obstacle of one side of the lower limb caused by brain injury. The lower limb wearable walker can help them get the ability to walk, but if they want to walk out the normal gait like ordinary people, the gait planning of the lower limb wearable walker is necessary. Gait planning is the basis and key for man-machine coupling walking and maintaining stability. Firstly, through the analysis of the movement of each joint of the lower limb, the overall mechanism of the lower limb wearable walker is designed. Secondly the gait planning is carried out. The part between the joints of the leg of the walker is regarded as a homogeneous rigid link, nine special time points of each joint in the complete walking cycle are extracted, and the coordinates and angles of the joints at each time point are analyzed. Combined with the cubic spline interpolation method in Matlab software, the motion track of the joints is simulated. Finally,the gait planning data is analyzed to obtain the coordinates of the barycenter projection point, fit the motion track of the barycenter projection point, and analyze whether the track always falls in the support area. The results prove that the barycenter projection point is always in the supporting area, which indicates that the gait planning meets the stability requirements.

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.

Bashan Mountain is the division line between middle subtropical climate and northern subtropical climate in China.The further analysis and understanding of the vertical variation of near surface temperature under such complex terrain can provide foundation and basic data for climate change， ecological monitoring and ecological environment protection in this region.Based on the measured data of daily near surface temperature on the northern slope of Micang Mountain during 2013 -2019 from four automatic stations and 3 surrounding meteorological stations， which covers an elevation difference more than 1400 m， combined the sounding data at Hanzhong sounding station from 2017 to 2019， the lapse rates （γ） of near surface temperature and ambient atmospheric temperature were compared， and the vertical variation of near surface temperature on the north slope of Micang Mountain was analyzed， also its vertical climate zone is discussed.The results show that： （1） The near surface temperature decreases with the increasing altitude， its monthly average temperature reaches the highest and lowest in mid-July and January respectively.The average annual γ is 0.624±0.136 ℃·（100m）-1 during the observation period， close to that of free atmosphere.The average monthly γ is the smallest in December， increases gradually to August and then decreases， representing a distinct seasonal trend that steeper lapse rates occurred during warmer months， while shallower lapse rates occurred during colder months.The seasonal γ are 0.647±0.099， 0.732±0.103， 0.605± 0.113 and 0.508 ±0.120 ℃·（100m）-1 in the spring， summer， autumn and winter， respectively.The variation of maximum/minimum temperature is similar with that of average temperature， with an annual γ 0.646±0.185 and 0.606±0.166 ℃·（100m）-1 respectively.The average annual daily range has no obvious difference in each height， fluctuating between 7 ℃ and 10℃， and has no obvious linear relationship with the height.The annual range decreases linearly with the increasing height.（2） The decreasing trend of γ has changed since 2008， which has largely contributed to the narrowing of the radiation difference at areas between higher and lower， and the opposite vertical change trend of aerosols.（3） With the increase of height， the accumulated temperature of daily average temperature passed 0， 5 and 10 ℃ decreases linearly， and their γ is almost about 213 ℃·（100m）-1， their initial day delays and the final day advances， and the duration shortens， and decreases by 3.4， 6.1 and 7.0 d·（100m）-1， respectively.（4） The hierarchy of ambient air temperature changes with height is different clearly among 0.5~1.0 km， 1.0~2.5 km， 2.5~4.5 km and 4.5 km above， in where their temporal variation of air temperature γ is also significantly different， reflecting the comprehensively topographical impact of Qinghai-Xizang Plateau， Qinling Mountain， local Micang Mountain and surface on air temperature.The γ of monthly air temperature near the surface is slightly greater than that of ambient air temperature， which is similar with that of 0.5~1.0 km after May.（5） The vertical climate zone can be divided into northern subtropical zone， warm temperate zone and middle temperate zone， which are between 500~1000 meters， 1000~1500 meters and 1500~2500 meters respectively.

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.

Protocol state machine active inference is a technique that relies on active automata learning.However, the abstraction of the alphabet and the construction of the mapper present critical challenges.Due to the diversity of messages of the same type, the response types of the same type are different, causing the method of regarding the message types as the alphabet will result in the loss of states or state transitions.To address the issue, message types were refined into subtypes according to the different responses and a progressive active inference method was proposed.The proposed method extracted the state fields from the existing protocol data to construct the initial alphabet and the mapper, and obtained the initial state machine based on active automata learning.It then mutated the existing messages to explore the response sequences, which were inconsistent with the current state machine.The mutated message was regarded as a protocol subtype and added to the alphabet, and a new state machine was inferred progressively based on the new alphabet.In order to reduce the interactions, a pre-response query algorithm was proposed based on prefix matching for the caching mechanism in the active automata learning.The ProLearner tool was utilized to evaluate the proposed method in the context of the SMTP and RSTP protocols.It is verified that the pre-response query method can effectively reduce the number of actual interactions, with an average reduction rate of about 10%.

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.

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.

ObjectiveTo establish a reverse osmosis technology-based method for enrichment of virus in water samples. MethodsTwo inactivated virus vaccines and two viral nucleic acid plasmids were added into simulated water samples and detected with real-time quantitative reverse transcriptase PCR (qRT-PCR) after reverse osmosis-based enrichment. Reverse osmosis membrane material, membrane pore size, and filtration time were optimized in the enrichments. ResultsThe enrichment efficiency increased with the decrease of pore size of the reverse osmosis membrane. The average virus enrichment efficiency of reverse osmosis membrane with the pore size of 0.10 μm was 22.86 ± 0.84% for 2 simulated water samples. The virus enrichment efficiency of nylon, cellulose acetate and polyethersulfone membranes were similar between each other. The enrichment efficiency goes up with the increase of filtration times, but the difference in the efficiency was not significant between two and three times of filtration. ConclusionThe efficiency can be up to 32.64% for the enrichment of polio virus in water samples using cellulose acetate filter membrane with 0.10 μm aperture and two times of filtration.

Objective: The research is to explore the enzyme inhibition of Perilla crude extract, and to preliminarily elucidate the pharmacological substance basis of them on hyperglycemia, hyperuric acid and hyperlipidemia. Methods: The content of flavonoids and phenolic acid in UV extract was determined and showed the active components associated with enzyme inhibition. In vitro experiments, the inhibition of Perilla extracts on different enzyme activity was determined and the inhibitory activity was evaluated by IC50. Molecular docking was used to predict the targets of Perilla crude extract on pancreatic lipase and amylase inhibition. Results: Flavone content in the crude UV extract was 0.309 8 mg/mg, and the total phenolic acid content was 58.59 mg/g. The IC50 values of Perilla crude extractd for α-amylase, xanthine oxidase, pancreatic lipase and acetylcholinesterase were 0.273, 0.244, 0.347 and 0.018 mg/mL, respectively.Apigenin-5-O-β-D-glucosine, xyrhinin-7-diglucosotide, apigenin-7-glucosine, cannol-3-O-ruassin, rosemary acid, rutin and others were the effective active components of perilla crude extracts. Conclusion: The Perilla crude extracts all have certain inhibitory activities on four enzymes, and presents a dose-effect relationship.

【Objective】 Fly ashes mixed with furnace slag-coal gangue have been increasingly used as a building material in Ningxia province of China. This paper analyzes the change in its mechanical properties at different mixing ratios. 【Method】 Fly ashes were mixed with cement at ratio of 3%, 4%, 5% and 6%, and with slag-coal gangue at 0%, 25%, 50%, 75% and 100%, respectively. The mechanical properties of each specimen were measured using triaxial test and ultrasonic test, from which we established the relationship between the unconfined compressive strength and the splitting strength for all treatments. 【Result】 The damage pattern of the specimens in the triaxial test was mediated by the surrounding pressure, showing a typical shear failure. The strength of all specimens can be estimated using slag content, cement content and the surrounding pressure. The scanning electron microscopy showed that the main hydration products of the specimens were C-S-H and Aft. The ultrasonic test revealed that the unconfined compressive strength of the specimens was positively correlated to the amplitude. 【Conclusion】 After reinforcing the fly ash with slag-coal gangue at appropriate ratio, it can be used as a building materials for dam and pavement construction.

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.

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.

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.

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

The characteristics of PM10 and its chemical composition from December 2015 to December 2017 are studied at three regional atmospheric background stations (Longfengshan, Lin'an, and Jinsha) in central and eastern China. The water-soluble ions (F-, Cl-, NO3-, SO42-, PO43-, Na+, K+, NH4+, Ca2+, Mg2+), carbon-containing compounds (OC, EC) and main elements in PM10 samples are analyzed. The average PM10 concentration at Lin'an (62.2±36.6 μg·m-3) during the whole period is the highest, followed by Jinsha (57.6±31.8 μg·m-3), and that at Longfengshan (57.5±55.3 μg·m-3) is the lowest. At those stations, the annual PM10 mass concentrations are lower than the national second-level air quality standard. The concentrations of PM10 in 2016-2017 show a downward trend, with the reductions of concentrations about 29.3% at Lin'an and 26.2% at Jinsha compared with the results during the year of 2013.The concentrations of SO42-, NO3-, and NH4+ during the whole period are 9.9, 8.2 μg·m-3 and 3.7 μg·m-3 at Lin'an, and 10.2, 6.7 μg·m-3 and 2.6 μg·m-3 at Jinsha, respectively, which are all higher than those at Longfengshan, with the average concentrations of 5.9 μg·m-3 for SO42-, 4.9 μg·m-3 for NO3-, and 2.1 μg·m-3 for NH4+. However, the ratio of NO3-/SO42- at Longfengshan and Lin'an are relatively higher. The concentrations of OC and EC during the whole period are 10.1 μg·m-3 and 2.7 μg·m-3 at Longfengshan, 6.1 μg·m-3 and 3.1 μg·m-3 at Lin'an, and 4.7 μg·m-3 and 2.3 μg·m-3 at Jinsha. Compared to the year of 2013, the concentrations of SO42-, NH4+ and OC during the whole period decrease by 38.1%, 26.0%, and 55.6% at Lin'an, respectively, and decrease by 46.3%, 51.9%, and 44.7% at Jinsha, while the concentrations of NO3- increase by 12.3% and 15.5% at Lin'an and Jinsha, respectively. The concentrations of EC decreases by 27.9% at Lin'an, but increases by 4.5% at Jinsha. The ratio of NO3-/SO42- increase obviously at all the stations, which indicates the increases of nitrate aerosols, due to the continuously control of coal combustion emissions and increase of car ownership.The seasonal concentrations of PM10, NO3-, EC and the ratio of NO3-/SO42- are lowest in summer at three stations. Meanwhile, the mass concentrations of SO42-, NO3- and NH4+ are basically higher in winter than in other seasons.

Objective To investigate the influencing factors of neoadjuvant chemotherapy (NAC) in estrogen receptor (ER) positive breast cancer and establish a prediction model of NAC efficacy. Methods A total of 321 ER positive breast cancer patients who received NAC treatment for 4 cycles followed by surgical treatment in our department from 2015 to 2018 were enrolled in this study. According to the efficacy evaluation criteria of solid tumors, the patients who achieved complete response (CR) or partial response (PR) after NAC were assigned into effective group, while those with stable disease (SD) and progressive disease (PD) into ineffective group. The differences of clinical and pathological parameters were retrospectively analyzed and compared between the 2 groups. Univariate and multivariate logistic regression analyses were applied to screen out the significant influencing factors. R Language was employed to establish the prediction models of NAC efficacy and pathological CR (pCR) rate of ER positive breast cancer patients. Then the prediction ability of the prediction models was evaluated by receiver operating characteristic (ROC) curve and correction curve. Results The overall effective rate of NAC and pCR were 75.39% and 15.26%, respectively, in the patients with ER positive breast cancer. Significant differences were seen in age, menstrual status, maximum tumor diameter, clinical node stage (cN), tumor blood supply, and ER and Ki-67 expression levels and chemotherapy regimen between the 2 groups (P < 0.05). Logistic analysis showed that cN, tumor blood supply, ER and Ki-67 expression levels were related to the efficacy of NAC (P < 0.05), while the rate of pCR after NAC was related to the maximal tumor diameter, tumor blood supply, and ER and Ki-67 expression levels (P < 0.05). The nomograms of predicting NAC efficacy and pCR in ER positive breast cancer patients were constructed with significant independent influencing factors. The area under ROC curve (AUC) of NAC Effectiveness Prediction Model for ER positive breast cancer patients was 0.785, and the cut-off value was (0.696, 0.760), and with calibration curve coinciding well with the reference standard. The AUC of pCR prediction model was 0.829 and the cut-off value was (0.673, 0.857), and the 2 curves were slightly biased. Conclusion Tumor blood supply, cN, ER and Ki-67 expression levels are the independent factors of NAC efficacy in ER positive breast cancer patients. The patients with axillary lymph node metastasis, low ER expression, high Ki-67 expression and good blood supply of tumor can achieve the best efficacy of NAC. Tumor maximal diameter, tumor blood supply, ER and Ki-67 expression levels are independent factors of pCR after NAC. The patients with small tumor, low expression of ER, high expression of Ki-67 and good blood supply of tumor have the highest probability of pCR after NAC. The established nomogram can primarily evaluate the benefit and probability of pCR in these patients.

Objective To investigate the association of visceral adiposity index (VAI) and 5-year outcome of prediabetes development, and compare its predictive value with other anthropometric indices (BMI, waist circumference and waist hip ratio). Methods The participants in this cohort study were selected from the epidemiological study of dynamic monitoring of risk factors for type 2 diabetes and integrated community prevention and treatment in Luzhou area from April to November 2011. A total of 1 125 participants with prediabetes were selected from the baseline survey. The subjects were divided into 4 groups according to the quartiles of the VAI (0.37~1.29, 1.30~2.01, 2.02~3.28, and 3.29~36.12), and all of them were followed up for 5 years to observe the outcome of prediabetes. Univariate and multivariate logistic regression analyses were used to analyzed the effect of VAI on the outcome, and the areas under the receiver operating characteristic (ROC) curve for VAI, BMI, waist circumference and waist hip ratio were calculated according to different quartiles to determine the predictive power of the indices. Results Of the 1 064 participants who completed the follow-up, 237 developed to diabetes. In the comparison of the subjects developing into diabetes, statistical differences were seen among the 4 groups, with the 4th quartile group (94 cases) > the 3rd quartile group (68 cases) > the 2nd quartile group (46 cases) > the 1st quartile group (29 cases, Chi-square=51.566, P < 0.001). Logistic regression analysis showed that after adjustment for any variables and for age, gender, height, systolic blood pressure, triglyceride, high density lipoprotein cholesterol, smoking and tea consumption, the individuals in higher VAI quartile group were more likely to develop to diabetes than those in lower group. The area under the ROC curve for VAI (0.662, P < 0.001) was significantly greater than those of other adiposity indices. Conclusion VAI is a risk factor that affects the outcome of prediabetes to diabetes, and may be regarded as a predictor of the outcome. With the increase of VAI, the risk of prediabetes conversion to diabetes increases. VAI is better than BMI, waist circumference and waist hip ratio in predicting the 5-year outcome to diabetes.

Objective To study the distribution, virulence genes, drug sensitivity and molecular characteristic of Bacillus cereus in five foods in Haikou area. Methods The Bacillus cereus strains were isolated from different foods including pastries, milk powder, fast food, Hainan rice noodles and its ingredients, collected from Haikou area, according to the standard GB 4789.14-2014. The specific gene groEL and 10 virulence genes were detected by general polymerase chain reaction (PCR) method. The sensitivity to antibiotics of isolates was performed with minimum inhibitory concentration (MIC). The pulsed field gel electrophoresis (PFGE) patterns of strains were analyzed. Results 197 strains of B. cereus were isolated from 626 food samples and the positive rate of B. cereus was 31.5%. In particular, most of B. cereus strains were isolated from Hainan rice noodles, accounting for 63.1% (140/222). All isolates carried at least one virulence gene, the rate of entFMgene was the highest, up to 99.0% (195/197). On the contrary, ces gene was the lowest at 2.5% (5/197) only. There were 175 (88.8%) strains that carried genes of nheA, nheB and nheC simultaneously. There were 27 (13.7%) strains that carried genes of hblA, hblC and hblD simultaneously. The sensitive rate of strains towards gentamicin, chloramphenicol, vancomycin and ciprofloxacin were 100.0% (197/197), 100.0% (197/197), 99.5% (196/197) and 92.9% (183/197), respectively. And the resistance rate of strains towards penicillin and trimethoprim-sulfamethoxazole were 100.0% (197/197) and 90.9% (179/197), respectively. The PFGE result showed 30 clusters and 117 genotypes. Conclusion The positive rate of Bacillus cereus in five foods in Haikou area was relatively high, especially in Hainan rice noodles, which should arouse attention and close observation. Targeted prevention and control measures can be carried out according to the characteristics of virulence genes, molecular typing and antibiotic sensitivity of the strains.

Oriented to 5Gmobile communication network combining with communication and computation,the characteristics ofmobile AR/VR information processing and transmission were analyzed,and the ability to integrate communication and computation was proposed,and the capability of integrating communication and computing was proposed.In the future 5Gmobile communication network,multi-level computing will be used to solve the problem of limited computing capacity ofmobile terminals by the capability ofmulti-level computing nodes in collaborative network.Intelligent transmissionmechanism could overcome the problem of unstable transmission capacity ofmobile channel by efficient spectrum sensing,layered coding and adaptive space port transmission,and themobile AR/VR service delay was ensured by using delay guaranteemechanism and cooperativemanagement of communication and computing resources.The research status and development trend ofmobile AR/VRmulti-level computingmodel,intelligent transmissionmechanism and service delay guarantee was reviewed,the existing problems were summarized and the next research direction was put forward.

Sematic attacks based on the data flow analysis bring big challenges to the code obfuscation.Concerning the data flow of virtual machine based (VM-based) code protection,the method transfers the mapping relation between the virtual registers and the op-code of the bytecode during executing,which means the uncertainty and complexity of the data flow during interpretive execution of the bytecode.In addition,three policies are proposed to address the problem that how to choose the length of rotation for each bytecode,which grows complexity of the protection.Finally,a prototype of VRR-VM (virtual machine protection system based on virtual registers rotation) was implemented.Experiment results show that the method is effective and applicable for anti-reversing.

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.

In order to study the propagation law of the crack in surrounding rock subjected to static-dynamic load, the poly methyl methacrylate (PMMA) are used to make specimens containing a single prefabricated crack and dynamic caustics experimental system with explosion load is used to conduct experimental research on the propagation laws of crack in roadway surrounding rock.Study has showed that there exists close relation among the extension displacement of the prefabricated crack, the damage degree of the specimen and confined pressure around the specimen.There is a negative correlation relationship between the extension displacement and the damage degree, which is closely associated with the confined pressure, presenting a rule of increasing firstly and decreasing later as the increasing of confined pressure.Changing the confined pressure around the specimen and keeping the explosion condition unchanged in the study, the prefabricated cracks all appear the phenomenon of alternative variation between extension and arresting, but the value of extension displacement reaches a maximum of 30.84 mm and a minimum of 10.98 mm when the value of confined pressure is 0 MPa and 0.4 MPa respectively, presenting a trend of decreasing firstly and increasing later as the increasing of confined pressure.There exists a close relation between energy release rate around the crack tip and propagation speed of the crack.When energy release rate increases, the propagation speed will increase then, but when the propagation speed decreases, energy accumulation occurs around the tip induced by the explosion stress wave, resulting in energy release rate increasing.

The formability of corners was improved by heating the corner area of high strength square tubes with induction coils.Under the premise of not impacting the undeformed zone,we obtained the ideal sectional dimension,microstructure and properties of products. In the hot roll forming process,the billet accumulated at the outside area of square corners without mold restrictions. With rising temperature,the accumulation became more serious. At the same time,microcracks deteriorated on the surface of the inner tube,while the cracks grew up in a form of arborization. A self-tempering process would be produced by residual temperature after hot roll forming,which could significantly reduce the residual stress. The residual stress sharply decreased as the temperature increased.When the heating temperature was above 650℃,the influence of self-tempering on the residual stress was greater than the extended capability of macrocracks and played a leading role; there was no crack when the distance was larger than 2/3 of diagonal length at flattening test.

To overcome the challenge of traditional roll forming process and equipment on high strength square tubes at room temperature,hot roll forming process using local induction heating was proposed to produce high strength square tubes.A series of tests including tensile testing,fracture morphology,scanning electron microscopy(SEM) and X-ray diffraction were performed to investigate the effect of hot forming temperature on the microstructure and mechanical properties of high strength square tubes.Experimental results show that as the temperature rises,the mechanical properties of the corners improve significantly.The fracture morphology gradually changes from cleavage fracture at room temperature to ductile fracture.The microstructures at the corners are developed from lath bainite to granular bainite and the polygonal ferrite begins to grow.Moreover,the circumferential and longitudinal residual stresses on the outside surface of the square tubes are reduced and reasonably redistributed.Based on the analyses of experimental results,the optimum forming temperature for high strength square tubes is 650 ℃.

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.

Background and objective This study aims to explore the effect of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKIs) on the lymphangiogenesis of lung cancer with EGFR mutation, as well as to determine the function of EGFR targeted therapy in relation to the inhibition of lymphangiogenesis during lung cancer treatment. Methods The EGFR double mutant lung cancer cell line NCI-H1975 is used to construct lung cancer xenograft models. The models are divided into two groups: the solvent control group and the EGFR-TKI treatment group. Each group includes five mice. The inhibitory effect of EGFR-TKI on the growth of transplanted tumors was observed. Immunohistochemical method and lymphatic endothelium specific antibody D2-40 were used in the experiment to observe the influence of EGFR-TKI on lymphangiogenesis in lung cancer. Results The weight and relative volume of tumors in the EGFR-TKI treated group were less than those in the solvent control group. The average lymphatic vessel density of EGFR-TKI-treated mice was 6.44 per case. This value was 10.70 per case in the solvent control group. Lower density of lymphangiogenesis was found in the EGFR-TKI treated group (P=0.023). The area and longest diameter of neonatal lymphatic vessel of the EGFR-TKI treated group were less than those of the solvent control group. Moreover, EGFR-TKI exhibited no significant effect on the invasion of tumor cells into the lymphatic vessel (P=0.519). Conclusion EGFR-TKI can inhibit lymphangiogenesis in EGFR mutant lung cancer while suppressing vessel diameter and expansion area.

Background and objective More than 35% Ib stage lung cancers have metastasised or recurrenced after operation, whose prognosis still remain poor. There’re much controversy over the necessity of adjuvant chemotherapy to them. This aim of this study is investigated the clinical and pathological characters influencing prognosis of the stage Ib non-small cell lung cancer (NSCLC) and to explore the indication of postoperative chemotherapy. Methods NSCLC patients (281 cases) who underwent lobectomy were examined. Cox proportional-hazards ratios were used to identify independent prognostic factors for survival. Kaplan-Meier survival curves were calculated to estimate survival rates. Results Kaplan-Meier analysis show that, cancerous embolus in the blood vessel or lymphatic vessel, histologic grade and tumor location were remarkerbly associated with mortality risk (P

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.

Based on Landsat images and digital elevation model data during 2000-2020, we investigated the spatio-temporal variations and driving forces of oases in the arid region of Northwest China, using an object-oriented method for oasis classification, and employing trends analysis, centroid migration, and geographic detectors methods. The results showed that from 2000 to 2020, the oasis area in the arid region of Northwest China exhibited a linear increasing trend, with a rate of 1079.66 km2 •a '. The growth rate of oasis area, from highest to lowest, was Alxa, Southern Xinjiang, Hexi Corridor and Northern Xinjiang, respectively. Oases in the arid region of Northwest China were mainly distributed in bands or dots along the northern and southern foothills of Tianshan Mountain, Kunlun Mountain, the northern foothills of Qilian Mountain, and the Alxa Plateau. The oasis area in Northern Xinjiang increased while that in the south decreased. Oases in Southern Xinjiang mainly expanded along rivers, with some edges experiencing recession. Expansion and recession of oases in the Hexi Corridor occurred along the rivers in the northwest. Alxa oasis expanded in a scattered pattern with no significant recession areas. The centroids of oases in Northern and Southern Xinjiang generally shifted northeastward, while that in the Hexi Corridor moved northwestward. The centroid of Alxa oasis fluctuated in a north-south direction. The interpretations of agricultural production potential for spatial differentiation of oases in Northern Xinjiang and the Hexi Corridor were the most significant, at 43.6% and 45.3% respectively. Precipitation was the strongest environmental factor affecting Alxa oasis distribution, with an interpretation of 27.6%. Soil types were the strongest factor affecting the distribution of oases in Southern Xinjiang, with an interpretation of 44.9%. The interaction among human activities in oases in the arid region of Northwest China was mainly enhanced by two factors, while the interaction among natural factors was enhanced by both two factors and nonlinear enhancement. [ABSTRACT FROM AUTHOR]

Seven grain quality traits were tested in the panel of 188 winter wheat accessions from Xinjiang. Twelve co-associated genetic loci were detected in four different environments via GWAS, explaining 6.021%-31.467% phenotypic variation. Two pleiotropism loci, located on chromosomes 6A and 2B, associated with protein content and settlement value, protein content and bulk density of wheat. Five pleiotropism loci, located on 3A, 1B, 6B, 7B, and 7D, shared by protein content and wet gluten content. One pleiotropism locus, located on 5B chromosome, associated with settlement value, bulk density of wheat and grain hardness. Three pleiotropism loci located on 7A, 3B, and 2D, respectively, which shared by protein content, settlement value, and wet gluten content, while one pleiotropism locus with unknown site was also associated with protein content, settlement value, and wet gluten content. These associated loci or genes might be employed to select favorite wheat genotypes, and cultivate elite wheat genotypes via marker-assisted selection in wheat quality breeding. Candidate genes at stable loci associated with multiple traits were searched, and 11 candidate genes that might be related to wheat grain quality with multiple traits and environments were screened. Among them, TraesCS6B01G347500 encoded a storage and transportation protein, TraesCS1B01G395400 encoded a carbohydrate transport protein/sugar transport protein, and TraesCS2D01G246500 gene encoded a protein ESKIMO1 related to cold tolerance, salt tolerance, and water conservation. These genes can be used as candidate genes for allelic variation analysis and marker development, provide molecular tools for wheat marker assisted selection breeding. [ABSTRACT FROM AUTHOR]