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This study establishes an analytical method for simultaneous determination of 19 Succinate dehydrogenase inhibitor fungicides pesticide residues in Green coffee by QuEChERS-Liquid chromatography tandem mass spectrometry. The Green coffee powder samples were extracted with acetonitrile by Homogenizer, the supernatant were purified by Magnesium sulfate anhydrous、PSA and C18, liquid chromatograhy - tandem mass spectrometry were used for analyzing 19 Succinate dehydrogenase inhibitor fungicides pesticide residues at positive ion mode. The results showed that the calibration curves of 19 targets showed good linearity with correlation coefficients of above 0.995 0 in the range of 1~100 ng/mL, the recoveries of 19 pesticides were 79.6%~109.4% and the relative standard deviations(RSD, n=6) were in the range of 1.4%~9.7% at spiked levels of 0.01、0.05 and 0.1 mg/kg. Limit of quantitation (LOQ) of all the tested pesticides were 0.51~4.60 μg/kg. This method has good linear relations, excellent stable and sensitive, accuracy and precision meet the requirement of quantitative analysis, it is suitable for quantitative analysis of 19 Succinate dehydrogenase inhibitor fungicides pesticide residues in Green coffee.

Biological matrix reference material is a reference material that combines the target material with the biological matrix. The biological matrix reference material has higher consistency with the authentic specimens in forensic toxicology, and its application has a positive effect on improving the accuracy of test results. This paper reviews the research on the matrix reference materials corresponding to three common biological test materials （blood, urine and hair）. In order to provide reference for the development and application of biological matrix reference materials in forensic toxicology, this paper mainly introduces the research progress of preparation technology of biological matrix reference materials and some existing products and their parameters evaluation.

ObjectiveTo analyze the characteristics of diphenidol poisoning cases and to provide clues and technical means for the identification of such cases.MethodsBiological samples of 9 deaths caused by diphenidol poisoning were detected by ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）, and the characteristics of these cases were analyzed retrospectively.ResultsMost of the deaths caused by diphenidol poisoning were young females. The dosage was between 60 and 300 tablets, and the mass concentration of diphenidol in the postmortem blood ranged from 0.87 to 99.00 μg/mL. There was no correlation between the dosage and the concentration of diphenidol in the blood.ConclusionDiphenidol poisoning has the characteristics of high concealment and lethality. More attention should be paid to suicide cases, and diphenidol should be recommended as a routine detection item to avoid missing detection.

To investigate the metabolic profiles of 4′-chlorodiazepam and diclazepam in vivo, the liver microsomal metabolism model was established. Firstly, the target substances were incubated in the water bath pot at 37 ℃ for about 4 h. Then the incubation buffer was terminated by ice acetonitrile. After that 10 μL of the supernatant was taken for analysing. The Agilent Eclipse plus C18 column (12.5 mm×2.1 mm×5 μm) was used and the 20 mmol/L ammonium acetate0.1% formic acid-5% acetonitrile (A) and acetonitrile (B) were served as the gradient elution. The metabolites and metabolic pathways were identified and clarified by liquid chromatography coupled with quadrupole Exactive Orbitrap mass spectrometry (LC-Q-Exactive MS) in the full scan-ddMS2 ion mode. The results showed that 4′-chlorodiazepam produced 5 phase Ⅰ and 2 phase Ⅱ metabolites in Wistar liver microsomes, and diclazepam produced 6 phase Ⅰ and 1 phase Ⅱ metabolites in Wistar liver microsomes. The differences of the metabolites might result from the substitution position of chlorine atom. And the main metabolic pathways of 4′-chlorodiazepam and diclazepam included demethylation, mono-hydroxylation, di-hydroxylation, O-glucuronidation in this work. On the basis of experimental results, phase Ⅰ metabolites M2 (demethylation), M3 (mono-hydroxylation), M4 (demethylation and mono-hydroxylation) of 4′-chlorodiazepam and M2′ (demethylation), M3′ (mono-hydroxylation), M4′ (demethylation and mono-hydroxylation) of diclazepam were proposed to be potential poisoning markers due to the high concentration level. Moreover, the metabolites and metabolic pathways of di-hydroxylation were the first reported. This study preliminarily clarified the metabolic pathways and main metabolites of 4′-chlorodiazepam and diclazepam in Wistar liver microsomes. It provided a theoretical basis for the pharmacokinetic and forensic scientific research of 4′-chlorodiazepam and diclazepam, which offered great value for the detection of related cases in laboratory.

To investigate the microscopic damage characteristics of rock materials under cyclic dynamic disturbance, granite was chosen as the research object, and the split Hopkinson pressure bar (SHPB) was used to outperform the cyclic impact test. Besides, with the nuclear magnetic resonance (NMR) technique, the porosity, crosswise relaxation time T2 distribution and magnetic resonance image (MRI) of the rock sample were obtained. The results show that within the range of the rock's elastic limit, the porosity reduces after the dynamic disturbance. The initial and final transverse relaxation time T2 shortens, which indicates the process of cyclic disturbance causes the formation of small pores, where the size and number of large pores decrease. The decrease of porosity does not mean that the number of all kinds of pores decreases; on the contrary, the number of small pores increases, and the decreased number of large pores is the root cause which leads to the decrease of porosity after dynamic disturbance.

To investigate the impact of the amount and change of traffic loads on the performance reliability of network,a simple traffic model for computer networks was established based on the traffic dynamics.The ratio between the ex-pected and the practical delay and the packet loss rate of each demand were used to characterize the performance reliabil-ity of the network.The performance reliability of a special local network was simulated and analyzed using the proposed approach.It was shown that the performance reliability of the network exhibited an obvious phase transition,no matter whether traffic loads were the Poisson traffic model or the Burstiness Constraints traffic model.In addition,the value of transition point can be considered as a measurement of network communication capability under special performance constraints.

High-dielectric polyvinylidene fluoride (PVDF) composites are widely used in electronic communications, new energy storage, aerospace and other fields due to their advantages of light weight, good flexibility, and easy processing. At present, PVDF matrix composites are mainly divided into two categories: inorganic/organic composite system and full organic composite system, but the application of full organic system is limited by its complex chemical process. This paper reviews the application status and research progress of three inorganic fillers in PVDF-based dielectric materials, namely ceramic particles, metal particles and carbon particles, and focuses on the research progress of expanded graphite, graphene oxide, carbon nanotubes, carbon black and carbon fiber in carbon fillers, and looks forward to the modification direction of inorganic fillers in PVDF composites. [ABSTRACT FROM AUTHOR]

Time-frequency domain reflection (TFDR) method has the advantages of maturity, convenience and high resolution, so it is widely applied to locate defects in various cables. To ensure the fracture defect of the instrumentation and control (I&C) cable can be effectively discriminated and precisely located in nuclear power plant (NPP), an improved TFDR method is proposed by intervening thermal stress in this paper. Subsequently, different degrees of fracture defects are simulated in a 50-meter multi-core I&C cable, and traditional TFDR and improved TFDR methods are used for detection and verification. Comparing the detection results of both, the peak localization of improved TFDR method for weak defect fracture is improved to 0.2, which is 2.5 times of the traditional TFDR method, and the localization error rate is less than 2.5%. Compared to the traditional TFDR method, improved TFDR method utilizes the thermal stress fluctuation variance curve as the basis for defect identification, the identification power of weak fracture defects can be substantially improved. The original localization distance can be corrected to improves the accuracy of weak fracture damage in improved TFDR method. So the effective identification and localization of weak defects can be further achieved in improved TFDR method.

Systematic reviews are the basis of evidence-based medical research, and high-quality systematic reviews represent the highest level of evidence for evaluating treatment effects. Traditional systematic reviews are mainly done manually, but the reading and screening of massive literature requires a lot of energy and time for clinicians, resulting in low efficiency, which cannot meet the needs of rapid decision-making. To address this problem, a number of automated tools have been developed. Thus, this article aims to systematically sort out existing automated tools for systematic review literature screening, and analyze their respective performance, characteristics, and usage to understand the current development status of this field and provide reference for related research and applications.

[Objective] The vulnerability of water resources in Changsha City was evaluated based on the connotation of vulnerability and its obstacles factors were identified, in order to provide a theoretical basis for the formulation of water resources management and control strategies in Changsha City, Hunan Province. [Methods] A comprehensive evaluation index system was established based on the vulnerability scoping diagram (VSD) conceptual framework. Game theory was used to determine the combined weight. The cloud matter-element model was used to comprehensively evaluate the vulnerability of water resources in Changsha City from 2014 to 2020. The obstacle degree model was used to diagnose and analyze the obstacle factors affecting the vulnerability of water resources in the city. [Results] ① From 2014 to 2020, the vulnerability of water resources in Changsha City showed a decreasing trend, from a medium level of vulnerability to a slight level of vulnerability; ② The evolution trends of vulnerability at each criterion level were different, the vulnerability of the exposure dimension was consistently high, the vulnerability of the sensitivity dimension was unstable, and the vulnerability of the adaptability dimension showed a clear downward trend; ③ The obstacle degree for the exposure criterion level was the highest, and per capita water resources, per capita daily water consumption, total industrial wastewater discharge, water storage capacity of the upper-type reservoir, and annual precipitation were the main obstacle factors that restricted the decline of water resource vulnerability in Changsha City. [Conclusion] In order to further reduce the level of vulnerability of water resources in Changsha City, the relationship between socio-economic development and the development and utilization of water resources should be coordinated in the future to reduce the pressure of human activities on the water resources system, and at the same time, the supervision and management of water conservation should be further strengthened, the investment in the construction of reservoirs should be intensified, and the utilization of recycled water and rainwater resources should be promoted.

Lithium sulfide is the baric raw material for the synthesis of sulfur based solid electrolyte. Lithium sulfide was prepared by carbonization reduction method with lithium sulfate as raw material and sucrose as carbon source. The thermodynamic calculation and analysis of the pyrolysis reaction of lithium sulfate and carbon were carried out. The effects of reluctant type, carnation temperature and carnation time on the content of Li2 S in the product were investigated. The results show that the main reaction for the formation of lithium sulfide occurs when the calcination temperature is higher than 660 °C, and 700 °C, and there will be side reactions for the formation of Li2O and Li2CO3. Using sucrose as reducing agent, carbonization coating was carried out under argon protection, followed by high- temperature calcination and reduction. Lithium sulfide with Li2S content of more than 99% could be obtained by reacting at 675 C for 9 h and 775 C for 1. 5 h. In the actual production process, the control of temperature and time is a benefit balance point. [ABSTRACT FROM AUTHOR]

Background In 2019, the National Health Commission launched the construction of compact county medical alliance to strengthen chronic diseases management in primary care, and the construction of chronic disease management models varies among county medical alliance sites. Xindu District, as one of the first national compact county medical alliance sites in Sichuan Province, has explored both dimensions of theoretical and practical innovation in the construction of the innovative model of chronic disease management in compact county medical alliance with treatment-prevention integration, providing a new approach for the innovative development of primary compact county medical alliance in China. Objective To analyze the innovation model and its effectiveness of chronic disease management in compact county medical alliance with treatment-prevention integration of Xindu District with the experience of international integrated medical models. Methods The chronic disease management in compact county medical alliance with treatment-prevention integration of Xindu District was constructed with "one center, two integration, three reforms and four safeguard mechanisms" under the leadership of Xindu District Health Bureau, to strengthen the management of chronic diseases mainly including hypertension and diabetes. Results As of June 2022, the number of hypertension or diabetes patients under standardized management in the district increased by 50.87% compared with the initial stage of construction, the number of hypertension or diabetes patients increased by 55.28% and 49.04%, respectively; while the proportion of patients with HbA1c

Pedestrian re-identification searches for specific pedestrians in different environments, which has attracted widespread attention from domestic and foreign scholars in recent years. At present, pedestrian re-recognition algorithms mostly use a combination of local features and global features, and the training test on a single data set has achieved very good results. However, the results in the cross-domain test are not satisfactory, and the generalization ability is low. This paper proposes a cross-domain pedestrian re-recognition method based on deep capsule network. Through the view angle classification training task, the model can learn the effective features of the pedestrian in the image, and these features can be directly transferred to the pedestrian re-recognition task, alleviating the problem of insufficient generalization ability of pedestrian re-recognition. Experimental results show that this model is superior to all current pedestrian re-recognition methods based on unsupervised learning and has good generalization ability. [ABSTRACT FROM AUTHOR]

The traditional level set has randomness in the location selection of the initial contour, and lacks the processing of edge information. Therefore, accurate extraction of brain tissue edges cannot be achieved. Therefore, firstly, the level set algorithm of fusion partition and Canny functional fuses the idea of partition and combines the morphological information of each region to complete the initial contour position selection, so that the initial contour contains more brain tissue, and improve the efficiency of brain tissue extraction. Secondly, the Canny operator is integrated into the energy functional, which improves the accuracy of detecting the edge of the macaque brain tissue while retaining the superiority of the traditional level set on the uneven grayscale image. Results show that the algorithm achieves accurate extraction of macaque brain tissue with an accuracy of up to 86%. [ABSTRACT FROM AUTHOR]

This paper reported a case of a 14-year-old female patient with schizophrenia of more than 2 years who had poor efficacy on atypical antipsychotics such as aripiprazole， risperidone and olanzapine， and who developed acute dystonia adverse effects during administration. Subsequently， the treatment was changed to clozapine therapy， and during this treatment， the patient's psychotic symptoms improved， but developed salivation and adverse effects such as clozapine-induced oculogyric crisis， slurred speech and dysphagia. This paper discussed this case with a view to providing a reference for clinicians in the recognition and management of oculogyric crisis caused by clozapine.

Objective To investigate the effect of hematoma puncture and catheter drainage on perihematomal cerebral hemodynamics in patients with spontaneous supratentorial intracerebral hemorrhage (ICH). Methods A total of 30 patients with spontaneous supratentorial ICH underwent hematoma puncture and catheter drainage. CT perfusion imaging (CTP) was used to determine regions of interest (ROIs) in the central hematoma, perihematomal edema (PHE), peripheral PHE (1 cm from the margin of PHE) and remote cortex in both hematoma side and enantiomorphic contralateral side. Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and time to peak (TTP) of ROIs were measured. Results 1) Different degrees of hypoperfusion existed in perihemtomal brain tissue after ICH: compared with enantiomorphic contralateral side, CBF (P = 0.000) and CBV (P = 0.000) were significantly decreased, MTT was prolonged (P = 0.000), while peak was not reached in the central hematoma; CBF (P = 0.000) and CBV (P = 0.000) were significantly decreased, while MTT was prolonged in PHE (P = 0.000); CBF (P = 0.000) and CBV (P = 0.000) were significantly decreased in peripheral PHE of hematoma side. There was no significant difference on CBF, CBV, MTT and TTP in remote cortex between hematoma side and enantiomorphic contralateral side (P > 0.05, for all). 2) The perfusion parameters showed stepped change from central hematoma to remote cortex: CBF and CBV showed a gradual increase (P < 0.05, for all), and MTT showed a gradual decrease from central hematoma to remote cortex of hematoma side (P < 0.05, for all), while TTP showed no significant difference (P > 0.05). There was no significant difference on CBF, CBV, MTT and TTP among central hematoma, PHE, peripheral PHE and remote cortex of enantiomorphic contralateral side (P > 0.05, for all). 3) CBF (P = 0.000) and CBV (P = 0.000) in PHE after operation were significantly higher than those before operation. Conclusions Hematoma puncture and catheter drainage can effectively improve the perfusion of perihematomal regions. [ABSTRACT FROM AUTHOR]

To study the changes in dielectric properties for thermally aged cross-linked polyethylene (XLPE) at different temperatures, the pure thermal and thermal-radiation aging tests are done. Thermal aging is carried at 80℃, 100℃, 135℃ and 155℃, lasting for 100 to 800 hours. The same conditions combined with 100 Gy/h gamma rays are done for thermal-radiation aged samples, and the dielectric spectra are measured from 25 to 200℃. The results show that the activation energy and values of β decrease obviously after the introduction of rays. At the same aging temperature and radiation conditions, electrical conductivity and relaxation peak frequency increase as the increasing aging time, which is a good reflection of dielectric properties during the aging process. Under different temperatures, the deviation in complex permittivity and modulus at lower frequency becomes more distinct compared with the values at a higher frequency. Finally, the dielectric properties under high temperature and low frequency could be a good indicator for the evaluation of XLPE degradation.

Objective To establish a simple and rapid method for detecting tumor cells based on multivalent aptamers. Methods Rolling circle amplification was used to form a long single stranded DNA scaffold with repeat sequences of poly T, then the obtained product was hybridized with the fluorescence signal chain of aptamer AS1411 (with poly A bases) which was nucleolin targeting. Then, a Multi-AS1411-LS recognition probe was constructed and characterized. The feasibility of probe Multi-AS1411-LS for cell line identification was analyzed by flow cytometry and confocal microscopy, and the recognition conditions were further optimized. Finally, the malignant tumor cells in clinically collected serous effusions were detected by our constructed probe Multi-AS1411-LS, and the specificity and sensitivity of our probe were evaluated. Results Our constructed probe Multi-AS1411-LS could recognize tumor cells in 5 min at room temperature, with the mean fluorescence intensity of cells higher by about 100 times than that of monovalent formats, and the minimum detection limit of 3 cells in 500 μL samples. The probe distinguished benign and malignant cells in 70 clinical specimens, with a sensitivity of 87.80% and a specificity of 93.10%. Conclusion This detection method is rapid and simple to operate, and has good specificity and sensitivity in the detection of malignant tumor cells in clinical practice.

In view of problems of complex structure, single measuring point and inconvenient installation of existing bolt force monitoring method, a bolt force monitoring system based on synchronous monitoring was designed. The system selects the diffusion silicon pressure sensor to collect the axial force of the bolt in a certain section of the roadway, and the force data of 8 bolts can be obtained simultaneously; the collected data are stored and transmitted after partial voltage filtering and AD conversion. The experimental results show that the system realizes synchronous monitoring of multiple bolts and anchor cables in a certain section of the roadway with high sampling rate, and its measurement accuracy can meet requirements of synchronous section bolts monitoring.

BackgroundThe main ore-bearing rock of the Husab Uranium Mine in Namibia, southern Africa, is white granite, and the radioactive element thorium content in the ore is high, which has a greater impact on the γ ray logging results.PurposeThis study aims to solve the problem of thorium's interference on the γ ray logging results by developing a γ ray spectrum logging instrument.MethodsA high-resolution LaBr3(Ce) scintillation detector was employed to build a new type of γ ray spectrum logging tool. Combined with cross-segment method of γ ray spectrum and techniques for separating the γ ray spectrum, the counting rates of thorium, uranium and potassium nuclides were greatly improved, so did the measuring range of the tool and logging speed. Experiment and calibration tests of this logging instrument were conducted on control holes, blast holes, national standard uranium calibration pit, etc., to verify its range, speed applicability, stability, repeatability, etc.ResultsTests results show that the γ ray spectrum logging achieves upper limit of uranium content measurement of 5.0% eU, and the logging speed of 0.067 m·s-1, satisfying the rapid quantitative measurement of uranium grades in the blast holes of the Husab Mine and accurately estimated the amount of uranium with superior measuring accuracy to the γ ray logging method.ConclusionsThe γ ray logging tool of this study reaches specification requirements of γ ray logging. It can effectively distinguish thorium, uranium and potassium nuclides, realizing the quantitative measurement of uranium content.

Xinhua phosphorus is a sedimentary phosphate deposit in China with strong REEs enrichment. In this study, Inductively Coupled Plasma-Mass Spectrometry ( ICP-MS ) and Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES) as well as rock-mineral identification, major and trace elements analysis together with sedimentology theory have been used to study geochemical characteristics of REEs in Xinhua phosphate rocks. XREEs of Xinhua phosphate rocks range from 800 X 10-6 to 1200 X 10-6 and are dominated by LREEs and Yttrium. REEs occur in collophanite by isomorphism dominantly. REEs pattern curves show remarkably negative Ce anomaies with values ranging from 0.28 to 0. 36 in Xinhua phosphate rocks , which are similar to those of Kunyang phosphate rocks , indicating phosphorus in the south of the upper Yangtze was formed in an oxidative environment and precipitated at the stable epicontinental sea of the passive continental margin. However, REEs pattern curves of the upper black shales and weak Ce and Eu anomalies are different from those of Xinhua phosphate rocks, which reflect black shales were formed in a deep and bathyal sea of a reductive environment. The Meishucunian period had a transgression process and the Meishucunian stage had an upward deep regressive sequence , the boundary between phosphate rocks and black shales possibly being a third-order even less scale sequence boundary. All of this sedimentology information is helpful to reveal the sequence of stratigraphy and marine sedimentary environment, which provides evidence for biological outbreak and stratigraphy sequence of early Cambrian in the Yangtze area , South China. [ABSTRACT FROM AUTHOR]

In order to research feature binding of visual perception, this paper used three different methods as follows. Firstly, constructed brain networks in resting state and tasking state, and divided them into some modules by use of CNM. Secondly, computed Z values between visual regions. Thirdly, computed the degrees of connection between different visual brain regions. Experiments confirm the two pathways of visual information processing, dynamic equilibrium characteristics of brain network and the important brain areas of visual feature binding. By means of studying cognitive processes of visual feature binding, these will help contribute to computer visual modeling process and improve the technology of image recognition. [ABSTRACT FROM AUTHOR]

It is a common phenomenon that large-scale mineral deposits occur around small intrusions or host within small intrusive bodies domestic and oversea. Such phenomena can be called as "mineralization with small intrusion". The phenomena occur in Dexing copper ore field in Jiangxi, Qitianling tungsten-polymetal ore concentration area in Hunan, Dachang tin-polymetal ore concentration area in Guangxi and Guidong uranium ore field in Guangdong, etc. Based on the variety phenomena of mineralization with small intrusion in South China metallogenic province and Yangtze metallogenic province, there is no choice for specific metallogenic epoch, deposit types, minerals assemblage or genesis, etc. Such phenomenon may reflect the preservation conditions of deposits more than ore genesis, and there is often a large batholith below the small intrusions with ore deposit. It is especially noteworthy for small intrusions around a large batholith, while isolated small intrusions may be poorly mineralized. As to the small intrusions intruded within large batholith, which has been ignored in the past, those small intrusions obliquely emplaced into host rocks might be important for mineralization. More attention has been paid on exploration large-scale deposits around small intrusions than the research on the mechanism of mineralization by small intrusion in South China, so that the study extent of mineralization mechanism, which is still relatively low, needs to be strengthened. [ABSTRACT FROM AUTHOR]

Currently the satellites ground systems provides single business, which lead to lack the ability of shared and collaboration. For solving these problems, this paper proposed a new satellites ground systems' architecture. It firstly studied the subsystems' service based on OGC service standards; then made a whole new satellites ground systems' architecture. At the end, it implemented a prototype of the ground systems. [ABSTRACT FROM AUTHOR]

Determination of aiming advance distance and maximum correction distance is important for the correction strategy on one-dimensional trajectory correction projectile. Focusing on the problem that the resistance device of one-dimensional trajectory correction fuze has limit increased-resistance capacity, the aiming advance distance and required maximum correction distance were analyzed using probability and mathematical statistics based on the principle of the maximum number of projectiles that fall into the designated field. Results show that, when parts of the projectiles are corrected, the correction strategy is the best in condition that the aiming advance distance is half of the maximum correction range and 2 times of the standard deviation of range error of uncontrolled projectile. Taking 155 mm shrapnel as an example, the reasonableness of the correction strategy above has been verified using Monte-Carlo simulation. With small aiming advance distance and the maximum range correction, the proposed correction strategy can make the greatest improvement of the range accuracy. Therefore it is perfect for one-dimensional trajectory correction fuze which has limited resistance capacity. [ABSTRACT FROM AUTHOR]

A video stabilization method based on sub-block gray projection algorithm is proposed. Firstly, each image is divided into sub-blocks which are filtered according to their gray gradients. After the sub-blocks of which gray gradients are lower than a threshold are removed, the calculation amount of projection is reduced and the motion estimation accuracy is improved. Then gray projection is done in the remained sub-blocks, and the global motion vector is calculated according to the local motion vectors and the interframe motion model. Finally, the trembling image is compensated to stabilize the image sequence according to motion compensating vector. The problems of that the global motion estimation accuracy is reduced by the local motion and the rotation motion of camera could not be estimated by traditional gray projection algorithm are effectively resolved by the sub-block gray projection algorithm. The experiment results show that the algorithm is more accurate and efficient than the traditional gray projection algorithm. [ABSTRACT FROM AUTHOR]

Considering the characteristics of unmanned aerial vehicle (UAV) aerial video, a UAV video stabilization method based on sub-block projection is proposed, which improves the accuracy of global motion estimation. This method divides an image into several sub-blocks and wipes off those sub-blocks which contain local motions and are textureless in gray level. Then the motion vectors of the sub-blocks remained are calculated respectively by using gray projection algorithm. Further, the global motion vector is estimated by local motions. Finally, after the motion decision, the tremble motion vector is used for motion compensation. Experiments on real video images of UAV demonstrate that the accuracy of this method is close to the standard motion estimation algorithm, but the time consumption is only one third of it. The result also shows that the effectiveness and the efficiency of the proposed algorithm are superior to the traditional gray projection algorithm. [ABSTRACT FROM AUTHOR]

In space attack-defense system, relative position and velocity estimation between intercepting satellite and target satellite is very important for orbit designing of intercepting satellite. In this paper, relative navigation is researched under the condition that orbit of target satellite is elliptical orbit and that the intercepting satellite has orbit maneuvering. Firstly, relative motion equations are derived with elliptical orbit of target satellite, and measurement equations are developed according to the geometric relation of measurement. Then the accelera-tion of intercepting satellite is introduced with its error, and the improved EKF algorithm is designed to increase navigation accuracy. Finally, the numerical simulation results verify the validity of this navigation method and show higher navigation accuracy. [ABSTRACT FROM AUTHOR]

On-orbit servicing spacecraft has become a hot research field at domestic and abroad in recent years, communication supporting spacecraft as a class of on-orbit servicing spacecraft can provide date forwarding service to the communication fault spacecraft, which can prolong the on-orbit life. In order to improve the communication supporting spacecraft antenna pointing accuracy, relative navigation algorithm of communication supporting spacecraft based-on particle filter is proposed, then more precise relative position and speed between two spacecrafts are obtained. This method takes radio equipment as the main measurement parts for its inherent characteristics, such as long measuring distance, high covering rate and all-weather work, and combines the advantage relative position and speed estimation of particle filter in nonlinear system filtering. Simulation results show that the new algorithm can effectively reduce the errors and improving relative position and speed estimation precision, ensure the space missions of communication support effectively. [ABSTRACT FROM AUTHOR]

This paper studies the problem of orbit control for intercepting satellite based on state feedback control considering parametric uncertainties, finite time performance, control input constraint and poles assignment. The sufficient condition of controller is derived by Lyapunov approach, and then the controller design istransformed into a convex optimization problem in terms of linear matrix inequality. An illustrative example shows that the system is asymptotically stable with the designed controller and the optimal performance is obtained with control input and poles assignment constraints. [ABSTRACT FROM AUTHOR]

A new acoustic emission source location method is presented based on near-field beamforming, that is, the acoustic emission source location method is established based the beamforming process of acoustic emission signals measured by a few sensors installed in small region. First, the propagation characteristics' differences between the acoustic signals and acoustic emission signals by using plate wave theory, and on the basis of these results the influencing factors in acoustic emission beamforming location is analyzed. Then, the present method is verified by artificial acoustic emission which is created by breaking a mechanical pencil lead on the surface of the plate. Finally, the present method is used to locate the rotor-stator rub fault occurring on the experimental device of rub fault, and identify rub position efficiently. The results show that it is an optional method for locating AE source. [ABSTRACT FROM AUTHOR]

To meet the requirement of trajectory correction fuze for missile-borne trajectory calculation with the features of low-cost, compact and high-performance, it is essential to verify the feasibility of utilizing a small micro-controller as trajectory calculator and controller. On the basis of the mathematical model of the projectile's particle trajectory and its numerical solution, the hardware and software MSP430 based were designed and debugged. The accuracy and real- time capability were verified by hardware-in-the-loop simulation. The result shows that the designed trajectory calculator and controller can meet the demand of trajectory correction fuze in accuracy and real-time capability. This research work might lay a preliminary foundation for developing low-cost and compact trajectory calculator and controller for trajectory correction fuze in the future. [ABSTRACT FROM AUTHOR]

Aimed at the nonlinear friction, disturbance torque and load variation in typical mechanical-electrical servo systems, by considering discrete-time output signals of angular position sensor as the observer input, the design of an angular acceleration boundary observer design is presented using sliding-mode control method. Based on the analysis of the structure of the boundary observer, we propose a method to determine the control input by designing the sliding mode. Furthermore, the key performance parameters and the design principle are provided. For a practical mechanics system, the designed angular acceleration observer exhibits the excellent dynamical performance under the nonlinear disturbance. [ABSTRACT FROM AUTHOR]

In order to realize the nondestructive monitoring for the development of internal structure of concrete in winter construction, the variation of dynamic elastic modulus of concretes with ages was investigated, which were cured under standard conditions, at constant negative temperature and at outdoor varying negative temperature. The results show that the high dodge of anti-freezing salts results in certain internal structure damage of concrete under standard curing conditions. In the negative temperature stage, the extraordinarily high value of dynamic elastic modulus of concrete is attributed to ice content in concrete. After moving the concrete cured at subzero temperature into a standard curing room for a certain period, the attenuation of dynamic elastic modulus can be applied to the determination of damage degree of concrete during subzero temperature curing stage, and the development rule of dynamic elastic modulus of concrete accords with that of compressive strength of concrete. Therefore, this non-destructive testing method can be applied to concrete construction in winter. [ABSTRACT FROM AUTHOR]

A new type two-dimensional gearbox with the output of rotating and reciprocating motion and transmission principle are proposed. The physical model of the two-dimensional gearbox is constructed by using the three-dimensional modeling software Inventor. The reciprocating motion related assembly is designed by applying the method of double eccentricity amplitude adjustment and eccentric wheel structure characteristics,the working principle of the output shaft rotation and axial reciprocating motion mechanism is mainly studied. The kinematics analysis of the model is carried out in software ADAMS and the output characteristics of the axially reciprocating assembly motion are obtained. Based on the theory above,the prototype of the two-dimensional gearbox is developed and manufactured. The plastic extrusion experiment is carried out by mounting the prototype on a single screw extruder. The rationality and feasibility of the two-dimensional gearbox with the output shaft rotation and reciprocating motion are verified.

In order to solve the severe challenge brought by the flight of ultra sonic missiles to the structure and thermal protection of missile bodies, and to improve the integrated load/thermal protection performance, an individual disturbance multi-strategy salp swarm algorithm for structural optimization design is proposed. Sobol sequence is introduced to homogenize the initial population for maintaining population diversity. The dynamic weight adjustment mechanism is used to improve algorithm speed. The variation factor and reverse solution strategy are fused to improve algorithm accuracy. The optimal Pareto solution can be obtained by using a temporary reserve. Finally, the improved algorithm is used to optimize the missile body structure and thermal protection system. Under the same environment, the optimal adaptive value and average convergence rate of improved algorithm are better than the standard salp swarm algorithm(SSA) and other optimization algorithms. Experimental data shows that the improved algorithm can solve the problem of mutual influence between thermal protection efficiency and structure quality. So the improved algorithm can not only improve algorithm speed and convergence accuracy, but also improve the load/thermal protection performance of the missile body structure.

Objective To explore the effect of extracellular vesicles （EVs） secreted by steatotic hepatocytes on the activation of macrophages. Methods The nonalcoholic steatohepatitis （NASH） model was established by feeding SD rats with high-fat and high-cholesterol diet （HFHCD）. Hepatic lesions of rats were observed by HE, Oil Red O and Masson staining, and the activation of M1 macrophages in the liver was detected by immunofluorescent staining. HepG2 cells were induced to be steatotic hepatocytes with palmitic acid （PA）, and their secreted EVs were isolated by ultracentrifugation. Then the effect of EVs on macrophages was observed by co-culture experiments and corresponding indicators were analyzed by RT-qPCR and flow cytometry. Results The results of HE, Oil Red O and Masson staining showed that the NASH animal model was successfully established. Immunofluorescent staining confirmed that the proportion of CD68+CD86+ cells in the liver of HFHCD group was significantly increased （P < 0.05）. RT-qPCR showed that EVs in the PA group could up-regulate the expression of M1 macrophage markers （IL-1β, IL-18） （P < 0.001）. Flow cytometry demonstrated that EVs increased the proportion of CD86+ cells in the PA group （P < 0.001）. EV inhibitors （GW4869） could block this promoting effect. Conclusion Steatotic hepatocytes can aggravate NASH progression by promoting the activation of M1 macrophages via EVs.

BACKGROUND Rare earth resources are essential for a wide range of advanced technologies, which have received considerable attention in the world. Bayan Obo is the largest rare earth mine in the world. The study on the distribution characteristics of rare earth elements (REEs) and heavy metal elements in the environmental media such as soil and plants in the Bayan Obo mining area can provide basic data for the investigation of the environmental status of the mining area and provide reference for its environmental restoration. OBJECTIVES To investigate the distribution characteristics of REEs and heavy metal elements in various environmental media at different areas in the Bayan Obo mine. METHODS Nine plant samples, six soil samples, one rock sample and one cow manure sample were collected from the Bayan Obo rare earth mine and surrounding areas. The contents of 15 rare earth elements and 8 heavy metal elements of these samples were determined by ICP-MS, which were used to study the behavior of elements and the variation rules in space. RESULTS The results showed that the distribution patterns of REEs in rocks, soil, plants, and cow manure samples were similar: obvious enrichment of light-REEs and depletion of high-REEs. The richest rare earth element in soil and plant was Ce, reaching 49.95% and 48.55%, respectively. The spatial variation law of the total content of rare earth element in Limonium bicolor (Bag.) Kuntze was consistent with the mineralization change of the three ore bodies: the main ore>the east ore>Dongjielegele ore. This indicated that the rare earth content of this plant was basically controlled by the minerality of the ore body, and it was more accurate to indicate the enrichment degree of rare earth in the growth environment. In addition, there was accumulation of Zn (465-778mg/kg), Cd (1.35-2.23mg/kg), Pb (181-431mg/kg) in the soil of the mining area. Some points of Cd and Pb were beyond the risk control value. CONCLUSIONS The ore, soil, and plant samples in Bayan Obo all show the characteristics of Ce enrichment. Moreover, the rare earth content of plants is highly correlated with the ore body where it grows. The REE content characteristics among the three media show obvious inheritance and consistency. Special attention should be paid to the mining and agricultural activities in the main mining area in Bayan Obo because of the accumulation of Zn, Cd, and Pb in these mining areas.

BACKGROUND Hydrogen and oxygen isotopes can be used to identify water sources and trace water cycles and have been used in hydrogeochemistry since the 1950s. Studies have been carried out on stable isotopes of atmospheric precipitation, rivers and lakes in Xinjiang.However, the research on hydrogen and oxygen isotopes of waters in Altay is scarce, except for atmospheric precipitation. Researchers found that the rainfall in the Altai Mountains during the warm season (April-October) increased significantly from 1959 to 2014. Due to this background of climate condition changes, it is meaningful to study the hydrogen and oxygen isotope compositions of various types of water bodies in the Altay region, at the southern foot of the Altai Mountains. OBJECTIVES To obtain the basic data of hydrogen and oxygen isotopic composition of water in Altay and reveal their spatial distribution characteristics. METHODS Hydrogen and oxygen isotope compositions of river water, lake water, spring water, snow water, and water from a mine pit in the Altay region of Xinjiang were determined by liquid water laser isotope analyzer (LGR DT100, America). The dissolved oxygen (DO), TDS, T, and pH of the water samples were measured using the German WTW3430 multi-parameter water quality analyzer. The concentrations of Na+, K+, Ca2+, and Mg2+ were analyzed by inductively coupled plasma-optical emission spectrometry (PE8300, PerkinElmer, USA). The concentrations of HCO3- and CO32- were determined by alkali titration method. Cl- and SO42- concentrations were analyzed by ion chromatography method. RESULTS The results showed that the ranges of δ18O and δD of the waters in the Altay area were from -15.4‰ to -5‰ and from -121‰ to -49‰, respectively. The hydrogen and oxygen isotope content of various types of water in the Altay region were significantly different. The δ18O and δD values of river waters varied from -15.4‰ to -11.5‰ and from -114‰ to -100‰, respectively, and the deuterium excess parameter varied from -12.4‰ to 12.4‰. The δ18O and δD of Ulungur Lake were much higher than those of surface rivers, with an average value of -5.95‰ and -78.5‰, respectively. The deuterium excess parameter of Ulungur Lake was much lower than those of surface rivers, with an average value of -30.9‰. The δ18O value (-14.9‰ and -11.8‰) of groundwater was similar to that of surface rivers, but δD (-114‰ and -121‰) was slightly higher than that of surface rivers, indicating that groundwater was supplied by surface rivers but may be affected by water-rock reactions. The δ18O and δD values of snow water and the water from a mine pit were -11.8‰ and -90‰, -11.6‰ and -106‰, respectively. The fitting lines for hydrogen and oxygen isotopes of the Irtysh River and Ulungur River were δD=1.7297δ18O-83.879 and δD=1.986δ18O-76.5, respectively. Surface rivers were remarkably different from the global and Urumqi atmospheric precipitation lines, indicating that apart from atmospheric precipitation, surface rivers were also recharged by glacier meltwater, and underwent evaporation and isotope fractionation during the water cycle.Due to the temperature and latitude effect of hydrogen and oxygen isotopes, the δD and δ18O showed significant positive correlation relationships with T, TDS, and the molar concentration of major ions such as Na+, K+, Ca2+, Cl-, and SO42-, also showing a significant negative correlation with the latitude of the sampling sites and DO (P < 0.05, n=32). CONCLUSIONS The hydrogen and oxygen isotope composition characteristics obtained in this study provide basic data for the stable isotope research of various types of water bodies in the Altay area.The precipitation in Altay has increased significantly in recent decades. Due to this background, it is indeed necessary to continue to conduct long-term and in-depth systematic research on the composition of hydrogen and oxygen isotopes in Altay's atmospheric precipitation and other types of water bodies.

BACKGROUND The Jiulong area in western Sichuan is an important rare metal production area in China, which has a large resource potential. As an ecological protection barrier on the upper reaches of the Yangtze River, the ecological environment of this area is fragile. Facing the huge opportunities of mining development and under the current situation of 'environmental protection first', it is urgent to investigate the environmental background of this area to support the development of national energy strategy. OBJECTIVES To evaluate the ecological risk of heavy metals in soils from the Jiulong Li-Be mining area. METHODS A total of 352 soil samples were collected. The concentration of 7 heavy metals (Cd, As, Pb, Cr, Cu, Ni, Zn) in soil was analyzed by NexION 300x inductively coupled plasma-mass spectrometer (ICP-MS). The comprehensive assessment methods including geoaccumulation index, pollution load index, potential ecological risk index, and health risk model, combined with GIS spatial analysis were used to study the spatial distribution characteristics and ecological risk of heavy metals in the soil. RESULTS The average concentration of all 7 heavy metals in the soil in Jiulong did not exceed the Chinese national standard. There was no soil heavy metals pollution in the studied area. Compared with the soil background value of Sichuan Province, the average concentrations of As and Pb were lower than the background; the concentrations of Cd, Cr, Cu, Ni, and Zn were higher than the background, which were 2.44, 1.04, 1.15, 1.28, and 1.17 times the background values, respectively. The spatial distribution characteristics of these elements except As were affected by biotite granite in the study area. The high concentration center of Pb and the low concentration center of Cr, Cu, Ni and Zn had an obvious correspondence with the spatial position of the rock mass. Except for the weak accumulation indicated by Cd Igeo, there was no accumulation of other heavy metals. Similarly, there was no potential ecological risk in the study area, except for the slight potential ecological risk of Cd. Spatially, the distribution of Cd single element potential ecological risk index was related to the rock mass, and the area without potential ecological risk corresponded to the location of the biotite granite rock mass. Heavy metals in the soil can enter the human body through direct contact with hands, mouth, and skin, and through inhalation. The hand-to-mouth approach is the most important way to generate health risks among all 3 approaches. Except hand-to-mouth approach of Cr, which has an acceptable and normal natural carcinogenic risk, there is no carcinogenic risk for other metals. CONCLUSIONS At present, there is no pollution of heavy metals in the soil in the studied area. The potential risk of heavy metals is low, and there are no non-carcinogenic and carcinogenic risks. However, due to the cumulative effect of heavy metals in the soil, close attention must be paid to changes in the concentration of heavy metals in the soil in the future mining development process, to prevent the risk caused by heavy metals pollution.

This paper is intended to conduct an experimental study to identify the influences of different proportion of heterogeneous agents in asymmetric tournament on agents' sabotage behavior. We come to the following conclusions by carrying out three experiments with 90 paid undergraduate and postgraduate student volunteers as subjects. First, heterogeneity of agents does not always reduce the effort level and sabotage level while it may make competition more intensive. Second, when the ratio of high capability competitors increases, the low ability competitors neither give up sabotaging nor form alliances to do it. Third, the agent's effort is increasing with the sum of other competitors' marginal cost of effort and is decreasing with his own marginal cost of effort. [ABSTRACT FROM AUTHOR]

In order to deal with the problem that the redistribution rule of real networks always lies between global shared rule and nearest neighbor shared rule or between even shared rule and extremely heterogeneous rule, a novel cascading failure model of complex networks is proposed. It can tune the load redistribution range and the distribution heterogeneity of extra load. Numerical simulation and analytic results show that the model can achieve better robustness against cascading failure than previous model by adjusting the redistribution range and heterogeneity. [ABSTRACT FROM AUTHOR]