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Star sensors installed on near-space vehicles are susceptible to earth-atmosphere radiation. As a result, the accuracy of star extraction and the performance of celestial system is significantly degraded. Aiming at this problem, a high precision star image pre-processing method to eliminate earth-atmosphere radiation is proposed. By analyzing the propagation mechanism of earth-atmosphere radiation, the atmospheric scattering model and ground reflection model are established, and an accurate earth-atmosphere radiation intensity model is constructed. Subsequently, the radiation intensity model is transformed into the background grayscale model in local ranges with the analysis of the relationship between the transmission path of the earth-atmosphere radiation received in the local ranges of the star sensor image plane and the pixel coordinates. Furthermore, the background estimation method is used to accurately estimate and compensate the stray light background under the influence of the earth-atmosphere radiation. Eventually, the performance of the proposed method is verified by simulated and real star images. The results show that the proposed method can effectively improve the SNR of star images and the accuracy of star extraction, and has good anti-interference performance.

In order to study the influence of the chemical structure of coal measure rock on the gas adsorption performance, taking the coal and rock samples of Shaqu No.1 Mine as the research object, the structure of coal and rock was analyzed from the microscopic point of view by using the experimental characterization methods such as inductively coupled plasma mass spectrometry, X-ray diffraction spectroscopy and Raman spectroscopy. Meanwhile, based on the theoretical calculation of DFT, Gaussian16 was used for molecular simulation to study the influence of coal and rock structure on the gas adsorption performance from the molecular point of view. The results show that L5 limestone contains a lot of organic matter and has a certain adsorption capacity for gas, while sandstone has a low adsorption capacity for gas, and coal has a much higher adsorption capacity for gas than L5 limestone. At the same time, the effect of chemical bond on gas adsorption is as follows: benzene ring > ether bond >Si=O>Al-O>CO32->H-O.

With the improvement of the accuracy requirements of high-precision long endurance inertial navigation system, the gravity disturbance has become the main error source of inertial navigation system.Is the key factor to improve the navigation accuracy whether it can be effectively compensated. The traditional compensation method based on spherical harmonic model cannot reflect the detailed information of the earth’s gravity field, and thus has poor compensation result for medium and short wave gravity disturbance components. In the traditional state estimation method, the Markov state model has poor accuracy in describing the long wave gravity disturbance component, so the compensation result of the long wave component is poor. The above methods can not compensate the actual gravity disturbance that has wide band with high precision. To solve this problem, a high-precision gravity disturbance compensation method based on spherical harmonic model and multi-sensor information fusion is designed in this paper. On the one hand, the method compensates the long wave gravity disturbance component by using the high calculation accuracy of the low-order spherical harmonic model in the long wave band. On the other hand, using strapdown inertial navigation/laser Doppler velocimetry/barometric altimeter to form a fully autonomous integrated navigation system, the residual medium and short wave gravity distur-bance component is established as a high-precision Markov model, so as to realize the state estimation and compensation of medium and short wave component. The simulation results show that the proposed gravity distur-bance compensation method can effectively improve the estimation effect of gravity disturbance, realize high-precision gravity disturbance compensation and have high navigation accuracy.

The technique of 3D deformation is one of the hot topics in the field of computer graphics.Current 3D deformation methods mainly learn the changes before and after deformation by aggregating localized adjacent voxel features,and fail to exploit the interrelationship between non-local voxel features,and the absence of contextual information prevents the model from capturing more discriminative features.To address the above problems,this paper designs a voxel deformation network based on environmental information mining,which can extract local and environmental information simultaneously,and extract environmental information from different spatial domains to improve the representation performance of the network,further modeling the relationship before and after the deformation of the object.Firstly,a novel self-attention mechanism is introduced.Specifically,the learning of the non-local dependence of different voxels is proposed to improve the ability of voxel discrimination.Then,a multi-scale analysis method is introduced to extract environmental information in different perceptual fields via multiple dilated convolution with different dilation rates,which provides more informative contextual features for the subsequent models.In addition,this paper analyzes the impact of feature fusion on the model and designs a method based on encoder-decoder feature fusion,which adaptively fuses the features extracted from the encoder and decoder to improve the nonlinear mapping capability of the model.Extensive experiments are conducted on our tooth dataset.The results show that the deformation prediction accuracy of the proposed method is improved compared to existing methods.

O'Sullivan-Mcleod syndrome is a very rare variant of MND with a good prognosis. Its clinical feature is distal lower motor neuron syndrome of both upper limbs, and there is no effective treatment at present. We reported a case of O'Sullivan-Mcleod syndrome in this paper.The patient exhibited with middle-aged progressive distal muscle weakness and atrophy of both upper limbs, without sensory, cognitive or behavioral impairment and without pyramidal tract sign. Laboratory examination, imaging and genetic tests showed no obvious abnormalities. EMG revealed neurogenic damage to the small muscles of both hands. Now we retrospectively analyzed the clinical features of a patient with O'Sullivan-McLeod syndrome, and data from 18 cases for comparative analysis, in order to improve its understanding by clinicians.

Recycling is the most effective way to dispose of waste polymer materials. It can not only reduce the harm of polymer materials to the natural environment, but also achieve the purpose of saving cost and turning waste into treasure. A self-made melt differential electrospinning device was used to recover the degraded polypropylene (PP) non-woven fabric as a raw material, and the special powder for recycling and degrading PP non-woven fabric after acid treatment and adding different plasticizers with a mass fraction of 10%. A blend of materials of sodium stearate, acetyl tributyl citrate (ATBC), and dioctyl adipate (DOA) was spun, and a nanofiber membrane was prepared at 300 ℃. The optimum degradation time of PP nonwoven fabric spinning and the effect of adding different plasticizers on the morphology, oil absorption performance and reusability of PP-degraded non-woven fabric nanofibers were investigated. Studies have shown that the addition of plasticizer ATBC works best. When the spinning voltage is 40 kV, the spinning distance is 70 mm, the spinning temperature is 300 ℃, and the ATBC mass fraction is 10%, the fiber diameter is as fine as 1.13 μm. The fiber membrane oil absorption ratio is 115.4 g/g, and the oil retention ratio is 70.3 g/g, which are 4 times and 3 times that of the initially commercially available PP nonwoven fabric, and has good reusability.

Boron-doped g-C3N4(BCN-n) was synthesized by grinding and calcination, and then boron-doped g-C3N4/bismuth oxybromide (BCN-n/BiOBr) materials were prepared by solvothermal method for the photocatalytic degradation of tetracycline hydrochloride(TCH) pollutants. The photocatalytic performance of BCN-n/BiOBr materials was investigated under different composite ratios, pH, catalyst dosages and different pollutant concentrations, and the materials were characterized and analyzed by TEM and XRD. The experimental results proved that the optimal composite mass ratio of BCN-2(BCN) : BiOBr was 2:1. Under the conditions of tetracycline hydrochloride solution concentration of 20 mg/L, stock solution pH 5.5, and catalyst dosage of 0.2 g/L, the degradation rate of tetracycline hydrochloride by BCN/BiOBr(2: 1) material reached 95.1%, compared with BCN and BiOBr materials under the same conditions, the degradation rates increased by 10.7% and 14.0%, respectively. The BCN/BiOBr photocatalyst is a promising photocatalytic material for the degradation of TCH. [ABSTRACT FROM AUTHOR]

Degradable polylactide (PLA) nanofibers can be prepared by solvent free melt electrospinning technology which is promising,challenging and green. The nanofiber membrane prepared by this method have high porosities and strong adsorption capacities,and thus are useful for treating the environmental pollution efficiently. The organic montmorillonite(OMMT) was introduced into PLA, and the PLA/OMMT nanofiber membrane were prepared at 260℃ by using a self-made melt differential electrospinning device. The effect of OMMT content of PLA nanofiber membrane on the morphology,the oil absorption property,the air filtration performance and the degradability was investigated, and the optimum OMMT content was obtained. The research shows that the thermal stability of PLA is increased and the crystallinity of PLA is decreased significantly after adding OMMT. When the OMMT content is 2%,the diameter of the fiber reaches 450nm. The oil absorption rate of the nanofiber membrane is 133.5g/g which is 4-5 times higher than that of commercially available PP non-wovens,and the oil holding rate is 84.2g/g. Moreover,the nanofiber membrane has good reuse performance. The air filtration efficiency of the nanofiber membrane for dust particles(≥ 0.3μm) is 99.31%,reaching the European standard H11 filtration class. The degradation of PLA/OMMT nanofiber membrane is improved comparing with the pure PLA, which reduces the second pollution and accords with the requirements of industrial green environmental protection.

Fermented feed is rich in probiotics, organic acids and other components, which is easy to digest and absorb by animals, and has high nutritional value. The palatability of the fermented feed is good, with a low content of anti-nutrient factors. It can improve the digestibility and utilization rate of animal feed, stabilize the structure of animal intestinal microorganisms, and enhance the immunity of the body. The paper mainly elaborates the concept and action mechanism of the fermented feed, reviews the effects of the fermented feed on the intestinal health, feed utilization rate, feeding cost and animal production performance, analyzes the problems existing in the application of the fermented feed in animal production, and prospects the future application of the fermented feed, in order to provide reference for the efficient utilization of fermented feed in animal breeding. [ABSTRACT FROM AUTHOR]

Surface physicochemical properties of aluminum alloy can be changed by different surface treatment methods, which determines the performance of adhesively bonded joints. This paper reviews the research status on the interfacial bonding strength and corrosion resistance of adhesively bonded aluminum alloys joints from the perspectives of surface roughness, surface micro-structure, surface oxide and coated chemistry properties. Then the problems and development of adhesively bonded aluminum alloys are discussed. The characterization of the aluminum surface physical and chemical properties and the relation model between the surface properties and the adhesive performance are considered to be focused directions for the further research.

In order to better evaluate the physical properties of slim cigarettes, correlation analysis and principal component analysis(PCA) were used to analyze a series of indexes such as cigarette weight, draw resistance, hardness, ventilation rate, tobacco loss from cigarette end, and percentage of loose end cigarette from 200 batches of slim cigarettes. A comprehensive method for evaluating the physical properties of slim cigarettes was established. The results showed that: 1) Three principal components were extracted by PCA(PC1: 32.301%, PC2: 30.623%, PC3: 13.774%), and their cumulative contribution rate of variance was 76.699% . Among them, PC1 reflected the deviation rate of the indexes, PC2 reflected the coefficients of variation of the indexes, and PC3 reflected the tobacco loss from cigarette end and the percentage of loose end cigarette. 2) A cigarette physical property evaluation model was established, and the cigarette physical property scores were classified into four categories: excellent, good, moderate, and poor. 3) Sample 8# had the highest score of 93.02 and belonged to the excellent quality category, while sample 15# had the lowest score of 59.94 and belonged to the poor quality category. Based on the scores of the test samples, the physical properties of slim cigarettes from different batches, machines and shifts could be systematically evaluated. [ABSTRACT FROM AUTHOR]

Using melamine and urea as raw materials, g-C3N4 was synthesized by calcining at 550 ° for 4 h via polycondensation pyrolysis method. g-C3N4 /TiO2 composite was prepared by hydrothermal combined calcination process with TiO2 precursor. Tetracycline was selected as the target degradation material. The effects on the degradation rate of tetracycline were investigated with the composition ratio and pH as independent variables. The properties of the material were characterized by XRD, SEM and BET. In the experiment, 70 mg g-C3N4/TiO2 powder was added to degrade 70 mL tetracycline solution with a concentration of 10 mg/L. The catalytic material was heated at 120 ° for 4 h and calcined at 500 ° for 2 h. The results showed that the degradation rate of tetracycline by g-C3N4 /TiO2, which the mass ratio of g-C3N4 to TiO2 was 12:100, reached 88.43% within 90 min under xenon lamp irradiation. The degradation rate of TiO2 was 64.73%, and the degradation rate was increased. [ABSTRACT FROM AUTHOR]

The terrain and geological conditions in the mountainous areas in southwest China are extremely complex with the characteristics of large range, wide scale, high frequency and sudden occurrence of geological disasters. The railway construction in mountainous areas inevitably needs to pass through these areas, so the disaster prevention monitoring of mountain railways has been paid much attention. On August 14, 2019, affected by successive days of heavy rainfall, the Chengdu - Kunming railway section K310+668-K311+232 experienced a high mountain collapse disaster and the railway was cut off for more than three months. In order to ensure the safety of the emergency workers and the operation safety of the trains in the transit period, an Air-Sky-Ground emergency monitoring method was adopted to realize three-dimensional monitoring of diseases. Based on the geological characteristics and the mechanism of disasters, dual-control displacement early-warning indexes considering rainfall intensity were established, and intelligent video recognition and monitoring technology was used to monitor foreign body invasions. The emergency monitoring period lasted nearly 8 months, and no false alarm nor missing alarm occurred in the system. The application results show that, compared with traditional monitoring means, the Air-Sky-Ground multi-sensor synergy monitoring technology fulfills real-time monitoring against disasters by means of incorporating points into planes and tridimensional protection and its warning reliability and stability is well validated. [ABSTRACT FROM AUTHOR]

To the characteristics of decentralized deployment of the command, control, communications, computers, intelligence, surveillance and reconnaissance (C4ISR) services, limited computing/storage resources for combat platforms, and high requirements for evolutionary real-time performance, the overall architecture of distributed monitoring and evolution of system state is designed based on hierarchical structure, and a dynamic adjustment method of service deployment scheme hierarchy is proposed. By analyzing the implementation difficulties of the resource coordination module in the overall architecture, the distributed deployment model of the C4ISR service is demonstrated based on defining the evolution cost and information flow path length. To the characteristics that the service deployment location and information flow path are included in the evolution scheme, a pair of exchange ideas, shortest path planning method and m-best strategy are combined to propose a greedy solution algorithm to realize the rapid generation of evolution scheme. The experimental results show that the method can effectively control the evolution range while ensuring the efficiency of system information flow, and can be suitable for the agile adjustment of service deployment method in the process of task execution. [ABSTRACT FROM AUTHOR]

The experiment was to compare the effect of different seasonal conditions on growth performance and serum biochemical indices of grazing yaks. Eight healthy yaks with good body condition were selected, which were grazed in the same pasture in warm season and cold season, respectively. The pre-test period lasted for 10 d, the formal test period lasted for 60 d. The results showed that the total weight gain and average daily gain of yaks in warm season group were extremely higher than those in cold season group (P<0.01). Serum albumin and ALT activity in warm season group were significantly higher than those in cold season group (P<0.05). The study indicates that the growth condition of yaks in warm season is obviously better than that in cold season, the digestion, absorption and utilization of protein were better, and the weight gain effect is better. [ABSTRACT FROM AUTHOR]

In order to improve the detection sensitivity of the laser seeker, the relationship between the bandwidth of the quadrant detector amplification module and the detection sensitivity of the laser seeker was fitted by numerical simulation. The influence of the pulse width of the guided laser irradiation on the bandwidth design of the quadrant detector amplification module was quantitatively analyzed. The bandwidth design method of quadrant detector amplifier was proposed, and the effectiveness of the method was verified by the exam with a laser seeker. The results show that the bandwidth design method of quadrant detector amplifier can effectively reduce the minimum detectable power of laser seeker. After the optimization design of the laser seeker quadrant detector amplifier, the minimum detectable power of the laser seeker can be reduced by about 60% compared with the original design, and the detection sensitivity of the laser seeker can be effectively improved. This study provides a reference for the design of photoelectric detection system of laser seeker. [ABSTRACT FROM AUTHOR]

TiO2 photocatalyst co-doped with N and La was prepared via sol-gel method using urea and lanthanum nitrate as precursors. The salicylic acid was used as the target to degrade the pollutants. The effects of N, La ratio, reaction system on the degradation rate of salicylic acid were studied. XRD, XPS, UV-Vis, BET and other characterization tests were used to analyze the properties of the materials. The results showed that the highest removal rate of salicylic acid by N/La-TiO2, which the doping ratio N : La=40: 0.1, reached 98.18% under 60 min UV light. The photocatalyst calcination temperature was 500 °C and the calcination time was 2 h. The removal rate of TiO2 reached only 50%. After doping N/La, the removal rate increased by nearly 2 times. pH=4 was the best reaction pH for degradation of salicylic acid by N/La-TiO2. Experimental quenching of active species proved that the main action of the degradation of salicylic acid by N/La-TiO2 catalyst under UV light was h+ and •OH. N in the N/La-TiO2 substituted for O in TiO2 lattic, which could form O-Ti-N and cause unique doping energy levels. La entered TiO2 lattice to produce more lattice defects. N, La co-doping reduced the average particle size, increased surface area by 2.1 times, increased pore volume by 2.2 times, and narrowed the band gap energy to 3.06 eV. N, La synergistically enhanced TiO2 photocatalytic activity. [ABSTRACT FROM AUTHOR]

Objective In theory, color-to-gray transformation is a process of dimensionality reduction, thus making information loss inevitable. Therefore, the goal of decolorization is to use the limited gray level range to preserve as much information of the original color image as possible. Researchers have proposed many related algorithms. However, the algorithms fail in the simultaneous preservation of the local and global contrast, as well as the contrast, color consistency, and grayscale pixel, of the original image. To solve these problems, we propose a new approach that can maximally maintain the features of the original color image. Method To preserve the structure and local information, we use a bimodal Gaussian distribution, followed by the difference between the pixel and its neighbors, to construct the error energy function. For global color consistency, we use locally linear embedding to build the energy function, which causes the same color pixels to exhibit the same gray levels in the result. For grayscale feature preservation, we distinguish grayscale pixels and specify that the gray values of grayscale pixels are known quantities and are initially unchanged during conversion. We then construct the energy function between grayscale pixels and other pixels. Thereafter, we build the objective function with the linear combination of the three energy functions and the gray image is obtained by solving the objective function using the iterative method. Result Experimental results show that our algorithm can preserve salient structure and fine detail, as well ensure that the same color can be transformed to the same grayscale and that the gray value of the grayscale pixel would be unchanged after conversion. Conclusion Our algorithm conforms to the degree of perception about contrast change in image and can preserve detailed information and global structure. The algorithm can be applied to digital printing, pattern recognition, and so on, and thus has great application value. [ABSTRACT FROM AUTHOR]

According to the features of vibration response of hydro-pneumatic balanced suspension, the method to design external characteristics of adjustable damping valve of suspension was put forward. The parameters of three-grade damping external characteristics were designed based on Taguchi method. The external characteristics of shock absorber were optimized to improve the transient response characteristic, riding and wheel ground adhesion index. The designed results indicate that, under stiff damping condition, the handling and startup comfort of vehicle are acceptable in comfort by designing the damping coefficient at low frequency properly. In addition, the performance of suspension is more robust. [ABSTRACT FROM AUTHOR]

PURPOSE: To analyze the status of 5-year-old children's oral caries in Shanghai from 2008 to 2011, and to provide information to evaluate oral health status and improve service level. METHODS: By using equal-sized randomly sampling method, this survey was carried out on the caries status of randomly selected 950 children aged 5 years in Shanghai respectively in 2008 and 2009, and 900 children respectively in 2010 and 2011. The data of prevalence of dental caries, dmft, caries filling constituent ratio and SiC index were collected. Statistical analysis was performed using SPSS 13.0 software package by means of independent-samples t test, one way ANOVA and Chi-square test. RESULTS: From 2008 to 2011, the prevalence of deciduous tooth caries among 5-year-old children was 63.47%, 64.00%, 64.89% and 64.44%, respectively. The mean dmft score was 2.96, 2.99, 3.23 and 3.09, respectively. The caries filling ratio was 10.93%, 12.76%, 16.96% and 20.63%, respectively. The SiC index was 7.10, 7.20, 7.74 and 7.37, respectively. The prevalence of caries and mean dmft showed no significant difference in four years (P>0.05), and the caries filling constituent ratio was remarkably increased (P<0.01). The SiC index was two times higher than dmft. Each year the prevalence of deciduous tooth caries and mean dmft in urban areas were lower than in suburban areas (P<0.01), but the children came from urban areas showed significant higher filling rate than those from suburban areas (P<0.01). Deciduous tooth caries were concentrated in one-third of children. CONCLUSIONS: The prevalence of deciduous tooth caries and dmft of 5-year-old children in Shanghai changed little, and the caries filling constituent ratio has increased year by year. To promote children' s oral health further, we still need to take more active preventive measures for high caries risk group. [ABSTRACT FROM AUTHOR]

The flow field and test condition in anechoic wind tunnel impacted acoustic propagation, and impacted noise sources identification. According to classical Beamforming algorithm for static source identification, making use of acoustic propagation law in flow field and shear layer of anechoic wind tunnel, this paper develops an aerodynamic noise sources identification method based on microphone arrays in anechoic wind tunnel, then numerical emulation and numerical proof are proceed. Numerical proof results indicate flow field and shear layer of anechoic wind tunnel impacted results of noise sources identification obviously, the influence can be corrected by making use of the computation method that introduced in this paper. [ABSTRACT FROM AUTHOR]

To make the stiffness of suspension adapt to different load, a new type of twin-accumulator hydro-pneumatic balanced suspension was proposed and its mathematical model was built up. Then the design principles and methods of its accumulators' parameters were proposed and proved through an example. The result indicates that, by appropriately matching the parameters of accumulators, such kind of balanced suspension can change the stiffness of suspension of multi-spindled vehicles properly and keep the same offset frequency under different load, thus the vibration performance of vehicles is improved. [ABSTRACT FROM AUTHOR]

Nonlinear supply chain inventory system models with forbidden returning and limited supply capacity are established in piecewise linear form. Stability analysis and simulation results show that under certain parameter settings, improper inventory cutoff by supply chain upstream participants may lead to complex dynamic behaviors of the whole supply chain inventory system. This finding is confirmed by calculating maximal Lyapunov Exponent. The statistical frequency of system states is derived. Results suggest that trade-off exists between inventory holding cost and system dynamic complexity. Target inventory level should be carefully set to ensure smooth operation in supply chains. [ABSTRACT FROM AUTHOR]

The corrosion products, microstructure and compressive strength of corroded cement matrix were examined by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and strength test instrument. Corrosion of oil well cement stone by sulfate (SO42-) and bicarbonate (HCO3-) during enhanced oil recovery (EOR) in adjustment wells was analyzed. The erosive effects on the compressive strength were studied to provide theoretical foundation for reasonably designing corrosion resistance cement system. The results show that the main corrosive products of cement cooperatively eroded by SO42- and HCO3- were gypsum, ettringite and calcite under the temperature between 38~60 °C, which has changed the material composition and microstructure of cement. Otherwise, the compressive strength of cement stone eroded by both of SO42- and HCO3- were much lower than that singly eroded by SO42- or HCO3- for all samples. When the corrosion time reached or exceeded 21 d, the compressive strength of corrosive cement was lower than that of un-corroded stone. The compressive strength of corrosive cement paste matrix precipitously declined with the increase of corrosion time and concentration of blend liquid of SO42- and HCO3-. When the corrosion time was within 14 d, compressive strength of the corrosive cement paste matrix increased with the rise of corrosion temperature. And when the cement was eroded over than 21 d, compressive strength decreased with the increase of temperature. [ABSTRACT FROM AUTHOR]

A new outside adjustable damper is developed. The characteristic of the outside damper can be controlled by operating on the adjustable valve. The working principle, elements construction and valve behaviors of the developed valve are studied. The damping characteristics is studied depending on the continuity equation, and differential equations of motion, as well as Bernoulli equation and others. The valve parameters' influence on the damping characteristic is studied by simulation. A new numerical model of the outside adjustable damper is built up. The results of both simulation and test on the bench are compared. The result shows that the developed outside adjustable damper can be adjusted on three stages. It can meet the requirement of the dynamic characteristic of the vehicle suspension system. Also, the simulation results tallies well with the test results on the bench, it indicates that the new numerical model is suitable for the developed damper. [ABSTRACT FROM AUTHOR]

Hemp has become popular in the study of natural fibers as its excellent ecological properties. In the article, degummed hemp was carded with cashmere carding machine. The fineness and length of degummed hemp, carded hemp and noil hemp were tested and the test data was statistically analyzed. The result showed that the fineness of hemp improved 15. 3% after carding, and the evenness of fineness decreased 46. 5% ; the average length of hemp decreased 1. 6% , but the evenness of length improved 13. 8%. The effect of removing coarse fibers by carding with cashmere carding machine was good, the evenness of length and fineness were both deceased largely, and it provided a basis for developing hemp/cashmere blending yarns or fabrics. [ABSTRACT FROM AUTHOR]

The dynamic response characteristics and failure modes of laminated glass panel supported on four sides subjected to blast loading with three magnitudes were studied in this research. The results indicate the overpressure of shock wave increase quickly to peak and then decrease in milliseconds. With the increasing of magnitude of explosion, the displacement and stress of laminated glass increase and cracks grow at center ring and extend uniformly around. The crack is radioactive expansion. At last, the panel can be ripen under higher explosion load and glass can be attached to PVB. The fracture model of test was simulated with finite element software LS-DYNA. The deviation between the test and simulation for the maximum displacement and stress at center are 38.7% and 20% respectively. The calculating results agree well with experiment results,which shows the numerical simulation is reliable. [ABSTRACT FROM AUTHOR]

Objectives: To explore the effect of electroacupuncture (EA) at "Baihui" (GV20) and "Shenting" (GV24) on the microvascular structure and related protein expression in the hippocampus of vascular dementia (VD) rat model, and to investigate the mechanism of EA in the treatment of VD., Methods: A total of 24 SD rats were randomly divided into sham operation, model, EA, and oxiracetam groups, with 6 rats in each group. Multiple cerebral infarction method was used to establish VD model. In the EA group, EA was applied to GV20 and GV24 for 30 min, once daily for 14 days. Rats in the oxiracetam group were treated with oxiracetam (50 mg/kg) by intraperitoneal injection, and the course of treatment was the same as that in the EA group. Learning and memory ability were evaluated by using Morris water maze test and new object recognition experiment. The cerebral blood flow was detected by laser doppler. The microvascular structure in the hippocampus was observed by transmission electron microscopy. The expression of vascular structure related proteins of platelet-derived growth factor receptor (PDGFR)-β, platelet endothelial cell adhesion molecule-1(CD31), neural cadherin N-Cadherin, Zonula occludens protein-1(ZO-1) in the hippocampus were measured by Western blot., Results: Compared with the sham operation group, the rats in the model group had a significant increase in time of first crossing the platform, a significant decrease in the number of crossing platform and the new object preference index ( P <0.05), a significant decrease in cerebral blood flow ( P <0.05), and a significant increase in the brain weight ( P <0.05). The structure boundary of pericyte and endothelial cells in the microvessels of the hippocampal CA1 area of model group was blurred, accompanied by obvious edema around the vessels and the reduction of tight junctions. The protein expression levels of PDGFR-β, CD31, N-Cadherin, ZO-1 were significantly decreased in the model group compared with those in the sham operation group ( P <0.05). Compared with the model group, the time of first crossing the platform of rats in the EA and oxiracetam group was shortened, the number of crossing platform were increased ( P <0.05), the cerebral blood flow was increased ( P <0.05), the brain weight was decreased ( P <0.05), the morphology and structure of pericyte and endothelial cells in the microvessels of hippocampal CA1 area were intact, accompanied by the increase of tight junctions. Additionally, Compared with the model group, the EA group had a significant increase in the new object preference index ( P <0.05), the protein expression levels of PDGFR-β, CD31, ZO-1 in the EA group were increased ( P <0.05), and the expression of PDGFR-β, N-Cadherin, ZO-1 in the oxiracetam group were increased ( P <0.05)., Conclusions: EA at GV20 and GV24 can improve the learning and memory ability of VD rats, and the mechanism may be related to the repair of microvascular structures and improvement of cerebral blood flow.

The aim of this study is to investigate the effects of Gynostemma pentaphyllum dried with two different methods(air drying and heating) on inflammation in acute lung injury(ALI) mice in vivo and in vitro. Lipopolysaccharide(LPS) was sprayed into the airway of wild type C57BL/6J male mice to establish the model, and the drug was injected into the tail vein 24 h after modeling. Lung function, lung tissue wet/dry weight(W/D) ratio, the total protein concentration, interleukin 6(IL-6), IL-1β, and tumor necrosis factor-α(TNF-α) in the bronchoalveolar lavage fluid(BALF), and pathological changes of the lung tissue were used to evaluate the effects of different gypenosides on ALI mice. The results showed that total gypenosides(YGGPs) and the gypenosides substituted with one or two glycosyl(GPs&#95;(1-2)) in the air-dried sample improved the lung function, significantly lowered the levels of IL-1β and TNF-α in BALF, and alleviated the lung inflammation of ALI mice. Moreover, GPs&#95;(1-2) had a more significant effect on inhibiting NO release in RAW264.7 cells. This study showed that different drying methods affected the anti-inflammatory activity of G. pentaphyllum, and the rare saponins in the air-dried sample without heating had better anti-inflammatory activity.

In order to understand the impacts of the reservoir construction on the diversity and ecological network of different microbial communities, seven sampling sites were set up in the Hengshan Reservoir in 2021. Water samples were collected from the surface and bottom of the reservoir. After filtering and extracting total DNA samples, high-throughput sequencing was carried out based on 16S and 18S rDNA to investigate the response of community structure, molecular ecological network, and keystone species of different microbial groups to water environment changes. The results showed that the Richness, Simpson, Shannon, and Pielou's Evenness indices of bacterial community in the surface and bottom layers were higher than those in the eukaryote community. The dominant community of bacteria included Proteobacteria, Actinobacteria, and Bacteroidetes, and the eukaryote community included Arthropoda, Ciliophora, Ochrophyta, etc. Moreover, the density and average clustering coefficient of the microbial networks in the surface waters of different phytoplankton communities were higher than those in the bottom waters. It was also observed that the microbial ecological networks in the surface waters were more closely related, and the number of nodes and edges, as well as the number of keystone species, of bacterial communities in the surface and bottom layers were significantly higher than those in the eukaryote microbial communities, indicating that the bacterial community network was larger, and the cooperative relationship and network connectivity between species were stronger. The interaction between bacterial community and eukaryote community in different water depths was dominated by positive correlation, and the negative correlation of the two groups in the bottom layer was slightly greater than that in the surface, indicating that the competition between bottom-layer species was greater than that between surface-layer species. In addition, the environmental impact factors of all species and keystone species of the community in surface water were basically the same, but they differed greatly in deep water, indicating that the influence mechanism of water depth change on keystone species was not the same as that of all species. The results further revealed the effects of reservoir construction on the stability and interspecific interactions of different microbial communities and provided a theoretical basis for predicting variations in microbial community and material cycling in reservoirs.

Eukaryotic microbial communities play an important role in biogeochemical cycling and maintaining the health and stability of ecosystems. However, little is known about the geographical distribution patterns, key driving mechanisms, and interspecific interactions of eukaryotic microorganisms in large rivers. This study investigated the geographical distribution characteristics, influencing factors, and interspecific interactions of eukaryotic microorganisms in sediments from the Jinsha River, a cascade hydropower development river in southwest China. The results showed that the α -diversity indices of benthic eukaryotic microorganisms in the Jinsha River increased first and then decreased. The community structure and relative abundance of dominant genera of benthic eukaryotic microorganisms differed significantly among different reaches. The results of distance decay analysis showed that the community assembly of benthic eukaryotic microorganisms in the Jinsha River was influenced by environmental selection and dispersal limitation. The results of variance partitioning analysis and neutral model further demonstrated that the geographical distribution pattern was mainly driven by dispersal limitation. The co-occurrence network analysis revealed that the interspecific competition and network connectivity of the cascade dam reach were weaker than those of the upstream natural reach, indicating that the interactions of benthic eukaryotic microorganisms were stronger in the upstream natural reach. This study supplemented the lack of data on the diversity and geographical distribution of benthic eukaryotic microorganisms in the river of southwest China and provided data support for the ecological response of benthic eukaryotic microorganisms in the river of cascade hydropower development.

Purpose: To investigate the expression and clinical significance of CD44 and CD33 in benign lymphoadenosis of oral mucosa(BLOM)., Methods: From January 2017 to March 2020, seventy-seven BLOM wax blocks from the Department of Pathology of Qingdao Traditional Chinese Medicine Hospital were selected as the experimental group, and 63 cases of normal oral mucosal tissue wax blocks during the same period were selected as the control group. Immunohistochemical method was used to detect the positive expression of CD44 and CD33 in the two groups.Spearman correlation analysis was used to analyze the correlation between the positive expression of CD33 and the positive expression of CD44 in the diseased tissues of BLOM patients.The general information about patients were collected.The relationship between the expression of CD33 and CD44 in the diseased tissues of BLOM patients and the clinicopathological characteristics of BLOM patients were analyzed. SPSS 21.0 software package was used for statistical analysis of the data., Results: The positive expression rates of CD33 in the control group and the experimental group were 95.24% and 63.64%, respectively, and the difference was statistically significant(P＜0.05). The positive expression rates of CD44 in the control group and the experimental group were 93.65% and 67.53%, respectively, and the difference was statistically significant(P＜0.05). The results of Spearman correlation analysis showed that the positive expression of CD33 in the diseased tissues of BLOM patients was positively correlated with the positive expression of CD44 (r=0.834, P=0.002). The expression of CD33 and CD44 in the diseased tissues of patients with BLOM were related to clinical type, degree of inflammation, presence or absence of lymphoid follicles, and lymphocyte infiltration(P＜0.05), but not related to age, gender, course of disease, location, and epithelial surface keratinization(P＞0.05)., Conclusions: The positive expression rate of CD33 and CD44 in the BLOM tissues decreased, which was closely related to the clinical type, degree of inflammation, presence or absence of lymphoid follicles, and lymphocyte infiltration.

Objective: To confirm the therapeutic effect of recombinant human thrombopoietin (rhTPO) on rhesus monkeys irradiated with 5.0 Gy 60 Co γ-ray, and provide experimental basis for clinical treatment of similar patients., Methods: Fourteen adult rhesus monkeys were irradiated with 60 Co γ-ray on both sides at the dose of 5.0 Gy (dose rate 69.2 cGy/min) to establish the acute radiation sickness model. The monkeys were divided into irradiation group (n=5), rhTPO 5 μg/kg group (n=4) and rhTPO 10 μg/kg group (n=5). Two hours after irradiation, the three groups of monkeys were injected with saline 0.1 ml/kg, rhTPO 5 μg/kg（0.1 ml/kg） and rhTPO 10 μg/kg(0.2 ml/kg), respectively. The general signs, survival, peripheral hemogram and serum biochemistry of rhesus monkeys were observed before and after irradiation, and the differences between rhTPO group and irradiation control group were compared., Results: After total body irradiation with 5.0 Gy 60 Co γ-ray, rhesus monkeys successively showed fever, hemorrhage, sharp decrease of whole blood cell counts in peripheral blood and disorder of serum biochemical indexes. Compared with the irradiated control group, a single intramuscular injection of rhTPO 5 μg/kg or 10 μg/kg 2 hours after irradiation could improve the symptoms of fever and bleeding, increase the nadir of peripheral red blood cells and platelets counts, shorten the duration of hemocytopenia, and advance the time for blood cells to return to the pre-irradiation level. The serum biochemical results showed that rhTPO could improve the abnormality of serum biochemical indexes in rhesus monkeys induced by 5.0 Gy total body irradiation to some extent. Compared with the two administration groups, the therapeutic effect of rhTPO 10 μg/ kg was better., Conclusion: A single injection of rhTPO 5 μg/ kg or 10 μg/ kg 2 hours after irradiation can alleviate the injury of multilineage hematopoiesis and promote the recovery in monkeys irradiated by 5.0 Gy γ-ray. It also improves animal signs and has obvious therapeutic effect on acute radiation sickness.

To understand the mercury (Hg) biogeochemical cycle in alpine regions under global warming, it is critical to identify the distribution and sources of Hg in aquatic ecosystems of the Tibet Plateau. The spatial distribution pattern and potential sources of Hg species including total mercury (THg), particulate mercury (PHg), and dissolved mercury (DHg) were investigated in surface waters of the Yangtze and Yellow River source basins during the wet season. The results showed that average ρ (DHg) in surface water of the Yangtze and Yellow River source basins were comparable[(2.96±1.26) ng·L -1 and (2.47±0.83) ng·L -1 , respectively], whereas the average ρ (THg)[(10.69±11.14) ng·L -1 ] and ρ (PHg)[(8.46±11.41) ng·L -1 ] in the source basin of the Yangtze River were significantly higher than that in surface water of the Yellow River source basin[(3.37±2.03) ng·L -1 and (1.13±1.02) ng·L -1 , respectively]. It is worth noting that the ecological risk of Hg in the study area was limited because of low Hg concentration and methylation level. In addition, the correlation analysis illustrated that the THg was mainly concentrated by PHg in the source basin of the Yangtze River. Specifically, the concentration variations in Hg were mainly affected by the input of glacier meltwater, soil erosion, and precipitation. By contrast, the main species of Hg in the source basin of the Yellow River was DHg, the distribution pattern of which was mainly controlled by DOC. Spatially, a significant negative correlation was found between ρ (PHg) and longitude in the source basin of the Yangtze River ( R 2 =0.46, P <0.01). The spatial distribution differences of river slope and soil erosion intensity were identified as the key factors leading to the decreasing trend of ρ (PHg) and ρ (THg) along the river flow in the source basin of the Yangtze River. The results of the PMF model further demonstrated that in the surface waters of the source regions of the Yangtze and Yellow Rivers, 51.4% of Hg derived from long-distance atmospheric deposition, 38.8% from erosion of soil rock or sediment via stream flow, and 9.7% from soil runoff or seepage input.

Malus floribunda Siebold. ( Malus ) is widely cultivated all over the world, which is of high ornamental value and breeding significance. Comparative analysis of the chloroplast genome can help enrich the phylogenetic relationship and facilitate germplasm utilization of Malus . Based on the whole genome sequencing data, a complete chloroplast genome ( M . floribunda ) with tetrad structure was assembled. The chloroplast genome (160 037 bp) was composed of a large single-copy (LSC) region (88 142 bp), inverted repeat (IR) B (26 353 bp), a small single-copy (SSC) region (19 189 bp), and IRA (26 353 bp). A total of 111 genes were annotated: 78 protein-coding genes, 29 tRNA genes and 4 rRNA genes. In addition, a large number of repeat sequences were identified in the genome, which was slightly different from that of M . sieboldii and M . toringoides . As for the relative synonymous codon usage, 30 high-frequency codons were found, and the codons tended to end with A/T. The results of interspecific sequence alignment and boundary analysis suggested the sequence variation of the LSC region was large, and the expansion and contraction of the SC region and IR region of the eight Malus species were generally similar. According to the phylogenetic analysis of chloroplast genome sequences, M . floribunda , M . hupehensis , and M . toringoides were grouped into one clade. The findings in this study can provide data support for the development of genetic markers and utilization of germplasm resources in the future.

Synthetic biology, a course with a sound theoretical system and a wide application range, plays a role in the cultivation of innovative talents in the field of bioengineering. To this end, we have set up a synthetic biology course in our university. First, according to the concept of imparting basic knowledge, highlighting innovative practice, and keeping up with cutting-edge progress, we assembled a high-level teaching team for synthetic biology. The team constantly adjusted and optimized the course contents and achieved a novel and reasonable course system. Second, we introduced frontier cases of synthetic biology reported in high-level journals, as well as breaking news in this field in classroom teaching, which enriched the teaching contents and aroused students' interest. Third, taking these cases as the breakthrough point, we guided students to in-depth discussions through the learning-centered teaching mode to improve students' abilities of critical thinking and theoretical innovation. In summary, the course has achieved good teaching outcomes and improved the cultivation of innovative talents. Therefore, we share our work with peer teachers, aiming to give new insights into the teaching reform of synthetic biology and other related courses.

Microbial communities play an important role in ecological processes through direct or indirect interactions. However, the interspecific interaction pattern of reservoir microorganisms has still received little attention. The Hengshan Reservoir in Jiangsu province was selected as the research area. Surface and deep water samples were collected to respectively explore the response of planktonic microbial community structure and the molecular ecological network to water depth changes, as well as to identify the key species of planktonic microbial communities in different water depths. The results showed that the richness and evenness of planktonic microorganisms in the surface layer were higher than those in the deep layer, and there were significant differences in the community structure of planktonic microorganisms in different depths. Water depth indirectly affected the planktonic microbial community by changing the environmental heterogeneity, among which the indicators such as TOC, NO 3 - , NH 4 + , and PO 4 3- had the most significant impact on the planktonic microbial community structure. In addition, the number of nodes and edges of the deep planktonic microbial molecular ecological network were significantly higher than those on the surface, and the type and number of key species in the deep planktonic microbial community were significantly higher than those on the surface, indicating that the network scale of the deep planktonic microbial community was larger; however, the interspecific cooperative relationship and network connectivity of the surface planktonic microbial community were stronger. These results will provide a scientific basis for the study of interspecific interactions of reservoir microbial communities and are of great significance for predicting the ecological law of microorganisms in reservoir ecosystems and the impact of global material cycles.

Objective: To compare the result of the artificial intelligence (AI) recognition-based fluorescence method and that of traditional flow cytometry in the examination of the sperm DNA fragmentation index (DFI) and assess the reliability of the AI-based fluorescence detection., Methods: Using flow cytometry and the AI-based fluorescence method, we examined the sperm DFI in the semen samples collected from 338 outpatients. We analyzed the correlation between the results and compared the positive rates detected by the two methods. We repeated the AI-based fluorescence method twice for each semen sample to observe its technical stability in the detection of sperm DFI., Results: The result of flow cytometry was well correlated with that of the AI-based fluorescence method in the detection of sperm DFI (R2 = 0.7131), but poorly correlated for low-concentration, sticky semen and some other extreme samples (R2 = 0.2065). No statistically significant difference was found between the two methods in the positive rate of detection. The AI-based fluorescence method exhibited an excellent technical stability (R2 = 0.9671)., Conclusion: The AI-based fluorescence method has an excellent technical stability in the detection of sperm DFI and the result is not significantly different from that of traditional flow cytometry.

In this study, four typical submerged macrophytes, namely Hydrilla verticillata , Elodea canadensis , Potamogeton crispus , and Ceratophyllum demersum , were tested for their chlorophyll content and antioxidant enzyme activity, to analyze their cadmium tolerance. The biota-sediment accumulation factor (BSAF) and plant transport factor (TF) were utilized to understand the accumulation capacity of the plants. Finally, the distribution of cadmium in submerged macrophytes was revealed through phytohistochemical methods, to provide theoretical support for the practical application of submerged macrophytes. The results showed that three of the plants, excluding C. demersum , exhibited varying tolerances to cadmium pollution in sediments, among which the tolerance of H. verticillata and E. canadensis were the strongest. P. crispus had the strongest accumulation capacity (BSAF was 2.32) at relatively low pollution levels (≤20 mg·kg -1 ). In this study, because of its weak root system, the BSAF of C. demersum was less than 1.0, indicating that macrophyte roots play an important role in phytoremediation of Cd-contaminated sediments. Comparing the TF of different plants, it can be found that the roots of H. verticillata had the strongest above-ground cadmium transport capacity, while P. crispus mainly accumulated cadmium in its roots. At the same time, when the cadmium concentration was 50 mg·kg -1 , cadmium was found to be evenly distributed in the stem organelles of P. crispus , in contrast to the other plants. Based on the cadmium tolerance and accumulation mechanism of the plants, and in consideration of real-world factors, H. verticillata and P. crispus were selected as ideal plants for repairing cadmium-containing sediments. Meanwhile, based on the different transport capabilities of plants, it is recommended that only the above-ground part of H. verticillate should be removed, while P. crispus should be uprooted regularly.

In this study, we hypothesized that the distribution patterns of trace metal elements in montane regions would be controlled by the local climate, human activities, vegetation distribution and soil development. Hence, we selected nine forest sites among the elevation of 850 m to 2650 m on the windward (western slope) and leeward (eastern slope) slopes of Ailao Mountain in Yunnan Province of China to determine the typical heavy metal concentrations in forest surface soils, and their differences for distribution trends along with the increasing elevations, and the corresponding environmental factors. The results showed that surface soil Cd, Sb, As, Cr, and Pb had relatively higher concentrations and distinct enrichment factors both on eastern and western slopes. Specifically, the concentrations of Cd and Sb in surface soils of the eastern and western slopes and Pb on the western slope all had obvious altitude distribution trends, which showed their concentrations increased with the increasing elevation. In addition, we found the concentrations of Cd, Sb, As, and Cr in surface soils of the western slope were significantly higher than those of the eastern slope at the same altitude. The correlation analysis and principal component analysis further depicted that the elevation trends of Cd and Sb were mainly controlled by the strong combining effects from long-range atmospheric input and soil organic matter strong absorption, and there was an obvious "cold trapping" effect in high altitude areas. The distribution variations of As and Cr were mainly derived from the weathering difference of soil parent material, while the variations for Pb were controlled by the weathering of bedrock minerals. This study highlights the important role of combining effects from long-range atmospheric input, and from precipitation and vegetation (such as "cold trapping" effect, promoting canopy filtration, litterfall deposition and bedrock weathering) on the distribution trends of trace metals in remote alpine soils.

Auscultation of heart sounds is an important method for the diagnosis of heart conditions. For most people, the audible component of heart sound are the first heart sound (S1) and the second heart sound (S2). Different diseases usually generate murmurs at different stages in a cardiac cycle. Segmenting the heart sounds precisely is the prerequisite for diagnosis. S1 and S2 emerges at the beginning of systole and diastole, respectively. Locating S1 and S2 accurately is beneficial for the segmentation of heart sounds. This paper proposed a method to classify the S1 and S2 based on their properties, and did not take use of the duration of systole and diastole. S1 and S2 in the training dataset were transformed to spectra by short-time Fourier transform and be feed to the two-stream convolutional neural network. The classification accuracy of the test dataset was as high as 91.135%. The highest sensitivity and specificity were 91.156% and 92.074%, respectively. Extracting the features of the input signals artificially can be avoid with the method proposed in this article. The calculation is not complicated, which makes this method effective for distinguishing S1 and S2 in real time.

As an important primary producer, diatoms play a key role in aquatic ecosystems. However, little is known about the geographical distribution characteristics and driving factors of diatoms in large rivers. In this study, based on a high-throughput sequencing dataset of microeukaryotes, we analyzed the diversities and community compositions of planktonic and sedimentary diatoms in the 1200 km mainstream of Lancang River, a typical large river in southwestern China. The results showed that the diversities of planktonic and sedimentary diatoms in Lancang River were higher in the upstream natural section, and the community compositions of both groups were significantly different among different river sections. Dam construction had a significant effect on the dominant genera. Variance partitioning analysis showed that dispersal limitation was a major driving factor for the distribution pattern of planktonic and sedimentary diatoms, with explanation proportions of 16.7% and 29.8%. Co-occurrence network analyses showed that the interspecific competition relationship and network connectivity of the planktonic diatom network were stronger than the sedimentary ones. The network connectivity of planktonic and sedimentary diatoms in the cascade reservoir section was higher than that of the upstream natural section. This study will help to better understand the biogeographical distribution of diatoms in large rivers and provide useful information for ecological responses of diatoms to dam construction in rivers.