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Objective To explore the mechanism of notoginsenoside Rg1 in preventing and treating Alzheimer′s disease (AD). Methods Rat model of AD was established by injecting amyloid beta peptide 1-42(Aβ1-42) into the lateral ventricle of SD rats. Then the animals were randomly divided into three groups: sham-operated group, model group and Rg1 treatment group. The treatment group was treated with Rg1 gavage and the sham-operated group was treated with saline gavage. Learning and memory capacity of rats were examined by Morris water maze experiment (MWM). Moreover, the contents of MDA and SOD in cerebral cortex were detected by chemical colorimetry; immuno-histochemistry was used to detect caspase-3 protein in the cerebral cortex and Western blot was employed to detect the expression of p38 and p-p38 proteins. Results Compared with the sham-operated group, the model group had a prolonged escape latency, reduced stay time in the target quadrant and reduced frequency of leaping over platform; increased MDA and decreased SOD in cerebral cortex; increased caspase-3 protein-positive neurons. The difference of p38 expression was not statistically significant and the phosphorylation of p38 was upregulated(P＜0.05). The rats in Rg1 treatment group had a shorter escape latency, increased stay time in quadrant Ⅲ, increased frequency of leaping over platform, decreased caspase-3 positive neurons and the phosphorylation level of p38,decreased MDA and increased SOD compared with the model group(P＜0.05). Conclusions Rg1 significantly improves learning and memory capacities, increases antioxidant capacity and plays neuro-protective effect in AD rat model by inhibition of p38 activation.

Objective Faults are among the most prevalent geological structures in oil and gas basins. Because of their significant connection to oil and gas resources, they have consistently attracted the attention of experts and scholars in the field, making them a hot research topic. Although previous researchers delved tirelessly into the correlation between faults, oil, and gas, new theoretical breakthroughs have been steadily emerging and have been used to promote advancements in oil and gas exploration. Nonetheless, there continues to be a dearth of thorough investigations into the underlying links between faults and the formation and distribution of oil and gas reservoirs, as well as methods for comprehensively and quantitatively defining the connections between faults and oil and gas. Methods The formation of a fault from inception encompasses multiple stages of development, including implicit and explicit stages, and differentiating the diverse growth stages of a fault, ranging from the initial embryonic stage to the terminal stage, poses a significant challenge. To address this issue, the Dongying Sag in the Bohai Bay Basin was selected as the focal point of this study. By employing physical and numerical simulation techniques, the researchers sought to replicate the entire life cycle evolution of the Chennan Fault, a basin-controlling boundary fault, from its embryonic stage to its terminal stage while elucidating the distinct characteristics of each stage. Building upon this foundation, the relative ages of the primary faults in the Dongying Depression and the various modes of fault activity at different stages were qualitatively and quantitatively determined, leading to the establishment of a reservoir-control model. Results The research findings indicate that normal faults tend to grow in six distinct stages: the embryonic stage (0 < RA (relative age) ≤ 1), characterized by microfractures or induced fracture zones; juvenile stage (1 < RA ≤ 2), with an intermittent connection of fault geometry; mature stage (2 < RA ≤ 3), marked by the connection of plate-like fault geometry and clear fault throw; declining stage (3 < RA ≤ 4), in which induced fracture zones form on both sides of the fault core, resulting in a shovel-like fault geometry; terminal stage (4 < RA ≤ 5), ramp-flat fault geometry, which has complex derived structures; and death stage (5 < RA ≤ 6), in which fault movement stops or undergoes inversion. The activity pattern of a fault is intricately linked to the duration and intensity of its age. Stable continuous, and high-intensity fault activity promotes the evolution of faults into their terminal stage. Research on reservoir control traps indicates that faults can create reservoirs at all stages of their development. However, as faults age, their ability to control reservoir formation strengthens. The types of traps influenced by faults transition from individual, isolated structures to a variety of arrangements. Moreover, the diversity of oil and gas reservoirs evolves from singular to multifaceted, and the size of these reservoirs expands from small to large. The embryonic and juvenile stage faults primarily influence closure; the mature stage faults predominantly impact sand and reservoir; and the declining stage and terminal stage faults primarily govern the overall distribution range of source rocks, as well as the migration, accumulation, and dissipation of oil and gas. Conclusion The reservoir control potential of the Chennan Fault was assessed by considering factors such as reservoir control advantages, the degree of oil and gas enrichment, and the scale of oil and gas accumulation. The reservoir control capacity of the Chennan Fault was classified as “strong.” Reevaluation of the fault’s reservoir control potential from the perspective of its developmental and evolutionary stages significantly enhances and elevates theoretical research on fault reservoir control and also advances exploration efforts in established mature areas. [Significance] Identifying the formation age and evolutionary patterns of extensional faults has immense theoretical and practical importance for comprehending alterations in the fault’s reservoir control capabilities. Moreover, it offers crucial guidance for oil and gas exploration, particularly for enhancing the reserves in existing exploration areas.

Objective: This study aimed to investigate the differences in enzymatic properties of endogenous transglutaminase （TGase） in silver carp and black carp. Methods: STG and BTG were purified from the muscle of silver carp and black carp, respectively, by 80% ammonium sulfate precipitation, Q-Sepharose FF, and Sephacryl S-200 HR chromatographies. Two enzymes were analyzed for relative molecular weights, peptide sequences, secondary structures, optimal reaction conditions, and thermal inactivation kinetics. Results: The purified STG and BTG showed similar relative molecular weights, of which the enzyme activities were 14.34 U/mg and 12.67 U/mg, respectively. Both enzymes showed differences in peptide sequences. The secondary structures of them were mainly the β-fold, though the content of β-fold in STG was slightly higher than that of BTG. The optimal temperatures for STG and BTG were both 50 ℃, and the optimal pH values were 8.0 and 7.5, respectively. The enzymes required Ca2+ up to 1 mmol/L for full activation. The activities of STG and BTG were enhanced by DTT, whereas PMSF, NH4Cl, NEM, EDTA, Cu2+, Ba2+, Zn2+, and Mg2+ showed inhibitory effects. When the temperature was 37~50 ℃, the passivations of STG and BTG by thermal treatment conformed to the first-order exponential decay kinetics with similar values of Ea. Conclusion: The primary and secondary structures of STG and BTG exhibited obvious differences, yet they still exhibited similar properties in terms of optimal reaction conditions and thermal inactivation kinetics.

In order to promote the application of diamond-like carbon (DLC) coatings in harsh marine environments, magnetron sputtering technology was used to deposit CrN-DLC coatings on 304 stainless steel. Subsequently, SEM, Raman spectrometer, XPS, EDS, nanoindentation instrument, friction testing machine, three-dimensional profilometer, and electrochemical workstation were utilized to analyze the surface and cross-sectional morphology, microscopic bonding structure, chemical bonding state, composition and element distribution, hardness, tribological properties and corrosion resistance of CrN-DLC films prepared under different nitrogen flow conditions. Results showed that the CrN-DLC coatings had a dense surface structure with no obvious defects, and the deposited coatings were all amorphous in structure. The coatings showed a 55% elastic recovery rate when 2 mL/min N2 was passed through, indicating that the CrN-DLC coatings had good toughness, and the wear rate of the coating prepared under this condition under simulated seawater rubbing against Si3N4 balls was only 8.63×10-10 m3/(N·m). In the electrochemical tests, the anodic polarization curves of all CrN-DLC coatings showed obvious passivation phenomenon. Among them, the corrosion current density of the coating through the 2 mL/min N2 was 2 orders of magnitude lower than that of 304 stainless steel, showing good corrosion resistance. Generally, the structural design and elemental doping of the CrN-DLC coatings could effectively improve the wear and corrosion resistance of 304 stainless steel, which enhanced the application of DLC coatings in the marine environment.

During the rolling process of profile ring, the design of the rolling cavity directly affects the forming quality of the final ring. In order to improve the cavity filling rate and reduce the production cycle time, this paper proposes a general evaluation method of the filling difficulty for profile ring rolling cavity by combining the response surface method(RSM) and the finite element method(FEM) with the step-type ring as the research object. Firstly, a universally applicable design method for profile ring rolling cavity is proposed, and based on the description of the rolling cavity, three design variables and a corresponding response objective are defined to achieve multi-objective optimization. Secondly, a finite element model of this step-type ring rolling process is established, and the response model is built and improved by significance analysis and analysis of variance(ANOVA) based on the forming simulation results. Then, the effects of different variables on the optimization objectives are comprehensively investigated by this response model. Finally, the evaluation method of the filling difficulty for profile ring rolling cavity is obtained by combining the contour plot of the response objective.

Objective·To investigate the impact of complications on the prognosis and lung injury of patients with tuberculosis..Methods·A retrospective cohort study was used for analysis, to select a total of 450 smear-positive tuberculosis (TB) patients, 323 males (71.8%) and 127 females (28.2%), from January to December 2018 at Shanghai Pulmonary Hospital, Tongji University School of Medicine, which were divided into non-complication group and complication group (diabetes, hypertension, liver diseases, kidney diseases and gallbladder diseases). Overall treatment outcomes and lung injuries in TB patients with and without complications were analyzed by using χ2 test. Stratified analysis of the impact of each comorbidity on the prognosis and lung injury of TB patients was performed. Kaplan-Meier analysis was used to analyze the temporal correlation between complications and tuberculosis prognosis.Results·Four hundred and fifty patients with a median age of 33 years were included, 173 of whom had complications: diabetes in 49 cases, hypertension in 23 cases, liver diseases in 83 cases, kidney diseases in 35 cases, and gallbladder diseases in 17 cases. The cure rate of TB patients without complications was 80.5%, which was significantly higher than that of the group with complications (P

ObjectivesIn order to improve ship propulsion performance and efficiency, and overcome such obstacles as numerous propeller parameters, complicated modeling, slow convergence of hydrodynamic numerical calculations and turbulent wake field effects, this paper proposes an efficient propeller optimization method.MethodsA parameterized propeller constructed with non-uniform rational B-spline based free form deformation (NFFD) technology is used as the output. The CFD numerical simulation is applied to predict its performance characteristics and the Gaussian approximate prediction model of the propeller performance is established based on the simulation data. The optimization model aims to improve efficiency and reduce the torque coefficient by using the second-generation non-dominated sorting genetic algorithm (NSGA-II) method to obtain the optimal solution.ResultsThe results show that under the uniform flow field and wake field behind the ship, the optimization results of the propeller have similar laws; that is, the blade width and thickness of the propeller show a decreasing trend, while the inclination angle shows an increasing trend. The flow velocity decreases in the wake field behind the ship, so the reduction in width and thickness and increase in inclination angle of the propeller blade are smaller than those in the uniform flow field. ConclusionThe method proposed in this paper can be used to achieve the more efficient optimization design of propellers under uniform flow fields and wake fields behind ships.

Based on literature analysis, this paper reviews the evolution path of Japan's food education policy and analyzes the content and purpose of the basic law of food education. Based on the perspectives of multiple objectives and multi-subject role division, the author summarizes the experience of Japan's food education policy promotion. Their experiences mainly include: clear division of labor between the central and local governments, central unification and respect for local autonomy. Food breeding roots from a young age; Diversified feeding action plans; Planning food education courses with characteristics.

Transthyretin(TTR) protein is a tetramer protein, synthesized mainly by the liver. TTR can be misfolded and deposited as amyloid fibrilae and deposited in the myocardial interstroma leading to transthyroxin amyloidosis cardiomyopathy (ATTR-CM). ATTR-CM was included in China's First List of Rare Diseases. Therapeutic strategies for ATTR-CM include blocking TTR synthesis in the liver, stabilizing TTR tetramers and destroying TTR fibra. Small molecule drugs such as tafamidis and diflunisal offer new treatment options for patients. Chlorobenzolic acid became the first drug approved by the U.S. Food and Drug Administration for the treatment of ATTR-CM. Small interfering RNA(siRNA)patisiran and antisense oligonucleotide (ASO)inotersen block TTR expression in the liver and have been approved for the treatment of ATTR variant polyneuropathy (ATTRv-PN)and are in phase Ⅲ trials for the treatment of ATTR-CM. Other siRNA drugs, vutrisiran, and ASO, eplontersen, are being evaluated for clinical efficacy. This article reviews the development of RNA-targeted therapeutics and gene-editing drugs using CRISPR-Cas9.

Objective: This study aimed to improve the recrystallization yield and purity of flavonoid. Methods: Taking the crude flavonoids from pomelo peel extracted by ultrasonic-assisted ethanol extraction as raw materials, the process parameters of ethanol recrystallization and purification of flavonoids were optimized by response surface methodology. Results: The main factors affecting the recrystallization yield of flavonoids were ethanol concentration, crystallization time, pH value, and the interaction between ethanol concentration and pH value, among which, the ethanol concentration affacted most significantly. Conclusion: The optimal recrystallization conditions of flavonoids were as follows: ethanol volume fraction of 24%, liquid-solid ratio of 10∶1 (mL/g), pH 3.75, crystallization temperature of 4 ℃, and crystallization time of 24 h. The crystallization yield of flavonoids was 8.76%, and the main crystallization product was naringin with a purity of 83.38%.

Objective: To explore the effect of air frying pan treatment on the quality of arrowhead starch. Methods:Taking arrowhead starch as the research object, the effects of thermal cycle mode of air fryer （treated at 160 ℃ for 10 min） on the physical and chemical properties of arrowhead starch with different mesh numbers were investigated. Results: The properties of starch changed after treatment in air fryer, and the properties of starch with different particle sizes were also different after treatment. Under the treatment of air fryer, the viscosity of arrowhead starch with different mesh numbers was significantly different from that of the original starch, the light transmittance increased significantly and the transparency increased differently, and the transparency of starch decreased with the increase of mesh number; At the same time, the gelatinization properties such as freeze-thaw stability also decreased significantly, and the solubility and swelling degree increased. The modified Sagittaria starch particles have broken appearance, shrinkage, increased shape change, and obvious change of characteristic diffraction peak. Conclusion: The air fryer treatment destroyed the particle shape of arrowhead starch to a certain extent, changed the properties of starch itself, which was simpler than other modification methods.

【Objective】In order to screen safe and effective fungicides to provide guidance for passion fruit production, seven biological fungicides were used as materials to study their control effects on the pathogen causing stem rot disease in passion fruits.【Method】Seven botanical and microbiological fungicides were used to determine their toxicity effects on the pathogen causing stem rot disease in passion fruits by mycelium growth rate method, the effects of fungicides on mycelium growth and spore morphology were observed, and their control effects were tested by in vivo inoculation method.【Result】All the selected fungicides showed inhibition effects on mycelium growth but had different effects on spore growth and morphology. Based on the indoor toxicity test results, among the botanical fungicides, Jinggangmycin showed the best inhibition effect with an EC50 of 7.79 mg/L, followed by Chunleimycin, ethylallicin and matrine, with the EC50 of 26.35 mg/L, 28.65 mg/L and 339.13 mg/L, respectively. Polyxins showed the lowest effect with an EC50 of 1 150.29 mg/L. Microbiological fungicide of Bacillus subtilis showed better effect than Trichoderma harzianum, with an EC50 of 3.2×106 CFU/g. The four screened fungicides of Jinggangmycin, Chunleimycin, ethylallicin and B. subtilis showed antifungal effects on different strains of fusarium pathogen. The in vivo inoculation test and field test showed that Jinggangmycin and B. subtilis had remarkable control effects on the pathogen causing stem rot disease in passion fruits, with in vivo inoculation control efficacy of 58.8% and 70.6%, respectively, and field control efficacy of 53.7% and 61.3%, respectively.【Conclusion】Two biological fungicides of B. subtilis and Jinggangmycin were screened out for their optimal control effects on the stem rot disease in passion fruits. It can provide alternatives or effective supplements for chemical fungicides for the control of stem rot disease, which could be promoted and applied.

Distributed Raman Fiber Amplifier (DRFA) is widely used in modern communication systems because it has a series of excellent features. Considering the existing problems of DRFA gain control, this paper studies and improves a method of Automatic Gain Control (AGC) of DRFA by Amplifying Spontaneous Emission (ASE) out of band. In view of the fact that DRFA gain is greatly affected by the performance of optical fiber link, this paper firstly theoretically analyzes the influence of the joint loss at the position 0 away from the pump source in the optical fiber link on the Raman gain control. Then the splice loss at different positions from the pump source is set to be equivalent to the splice loss at position 0. The relationship between Raman gain and out-of-band ASE power is modified so that the AGC of DRFA can be realized more accurately. The Optical Time Domain Reflectometer (OTDR) function is integrated in the DRFA module to detect the distance between the joint loss and the pump source and the loss value in the engineering optical fiber link. Experimental results show that the proposed AGC method can control the influence of joint loss on DRFA gain within 0.2 dB.

Objective: The study aimed to improve the storage quality of frozen cooked crawfish tail meat. Methods: Crawfish tail meat were immersed in different proportions of complex phosphate, trehalose and sorbitol antifreeze agents. The thawing loss rate, water content and distribution, water retention, salt-soluble protein, total thiol content, texture properties of crawfish tail meat after freeze-thawed were measured, and the microstructure changes were observed to evaluate the effect of each antifreeze agent. The antifreeze agent with better effect was selected as horizontal factor to design orthogonal experiment, so as to optimize the appropriate recipe of antifreeze agents. Results: 1.5% complex phosphate, 8% trehalose or 10% sorbitol had better cryoprotective effect; The compound antifreeze agent group （1% compound phosphate +6% trehalose +6% sorbitol） had the best cryoprotective effect, and the thawing loss rate was 9.97% under this condition, which was significantly lower than that of the single antifreeze agent group （15.95%, 17.44%, 16.78%）.The combined antifreeze agent group could significantly improve the binding ability of shrimp meat with water and inhibit the damage of ice crystals to muscle tissue during the freeze-thaw process. Conclusion: The combination of antifreeze agents （1% compound phosphate +6% trehalose +6% sorbitol） could effectively improve the cryoprotective ability of cooked crayfish tail meat.

The construction of offshore wind power is of great significance to the realization of the “dual carbon” goal and the construction of a new power system with new energy as the main body. Far away from land and complex sea conditions make the control, operation and maintenance (O&M) of offshore wind turbines face many challenges, which are key issues that must be taken seriously and solved in large-scale construction. This paper summarized the current development trend of offshore wind power and related research progress, analyzed the main problems faced by the control and O&M of offshore wind turbines, and sorted out the key technologies of offshore wind power from two aspects of intelligent control and intelligent O&M,so as to provide reference for carrying out frontier theoretical and technical research in this field.

Heart rate recovery, a widely used indicator in clinical evaluation of the autonomic nervous system, refers to the difference between maximum heart rate during exercise and the heart rate after 1 or a few minutes of cessation. It possesses advantages of being noninvasive and repeatable. Currently, heart rate recovery is extensively applied in cardiovascular diseases for evaluating disease severity, prognosis, risk of cardiovascular events, and mortality. This article primarily discusses the application value and current research progress of heart rate recovery in cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Aiming at the attitude cooperative control problem of multi-spacecraft system, the attitude estimation of the spacecraft is estimated by invariant extended Kalman filter (InEKF), and the attitude estimation of the spacecraft is made independent of the transfer matrix. Then, the multi-spacecraft special orthogonal group (SO(3)) attitude model is constructed by combining the undirected communication topology, and the attitude coordination error on SO (3) is deduced. Among them, an attitude coordination control algorithm based on the consistency theory is proposed based on the special orthogonal group SO(3). The radial basis function neural network is used to tit and compensate virtual disturbances. The proposed algorithm considers spatial disturbances to ensure that the collaborative controller is applicable to the entire attitude space. Multi-satellite attitude collaboration, tracking desired attitude, and collaboration under the constraints of actuator capabilities are realized. The system is analyzed based on LaSalle invariant set theory, proving that the system has global asymptotic stability. Finally, the effectiveness of the proposed attitude collaborative control algorithm is verified by using a six-satellite spacecraft system. [ABSTRACT FROM AUTHOR]

Aiming at the problem of link scheduling fairness in the in-band full-duplex access process of distributed wireless local area network (WLAN), a full-duplex link scheduling algorithm based on nodal scheduling weights (W-FD) is proposed. Load balance of link is realized by node scheduling weight, therefore the throughput of full-duplex link can be improved and the delay can be reduced. The algorithm is based on distributed network, and the nodes obtain the network topology and the state information of neighbor nodes in a self-organizing way. The sche-duling weight is calculated according to the data volume between nodes, mutual interference relationship and scheduling interval between links. The node with high scheduling weight in the neighborhood acts as the link initiator to establish a full duplex link. Result shows: compared with the half-duplex link scheduling algorithm (RTS/CTS), W-FD ensures the access fairness of nodes, reduces link scheduling intervals and improves network through-put and time delay performance; compared with the existing full-duplex link scheduling algorithm, W-FD can effectively improve the tail behavior of time delay in the traffic disequilibrium network, and ensure the network throughput as well as the scheduling fairness.

Fracture toughness is an important index to characterize the brittle state of reactor pressure vessel (RPV) steel. During the irradiation embrittlement study of RPV steel, small size compact tension (CT) specimens are generally used, because of the limited space for irradiation test. In order to understand the effect of CT specimen size on fracture toughness test result of domestic RPV steel, different sizes CT specimens of domestic A508-3 steel were tested in this paper. Size effect on fracture toughness data was studied by Beremin model method. Then the fracture toughness data normalization model (TSM, a modified toughness scaling model) of different sizes CT specimens was established. The results show that the fracture toughness increases with the decrease of sample size at the same test temperature. The normalized data of different specimens obtained by standard method has deviation. The TSM established in this paper can reduce the deviation of converted data. Key words: A508-3 steel, fracture toughness, size effect, Beremin model, data normalization model

Aiming at resisting the man-in-the-middle attacks in the domain name system protocol, a lightweight solution was proposed. The scheme introduced certificate less signature algorithm, removed the difficult-to-deploy trust chain to improve the efficiency and security of authentication. By using symmetric encryption technology, the proposed solution ensured the confidentiality of the message and increase the attack difficulty. The theoretical analysis proved the proposed scheme can resist common man-in-the-middle attacks. Experimental comparison results show the scheme has better performance than similar schemes.

In our previous study, it has been confirmed that the 50% ethanol extract of Euodiae Fructus is a hepatotoxic active part, and its metabolism in rat serum has been revealed. However, the metabolic pathway of traditional Chinese medicine in vivo is multiple. A diverse analysis for the metabolism behavior of components will provide us a deep understanding for the qualitative metabolic law and action process in vivo between prototype components and metabolites. In this study, ultrahigh performance liquid chromatographyquadrupole time of flight mass spectrometry (UPLC-Q TOF MS) was used to detect chemicals in rat bile, urine and feces after administration of Euodia rutaecarpa (35 g/(kg•d)) once a day for fourteen consecutive days. By comparing the BPI chromatograms of samples in positive and negative ion modes, it was found that the response signals in negative ion mode were all responsive in positive ion mode, and the response was better. So the positive ion data was selected for the subsequent analysis. The BPI chromatograms of blank bile and medicated bile, blank urine and medicated urine, blank feces and medicated feces were compared and analyzed. A total of 10 components in bile, 20 components in urine and 26 components in feces were detected. Further comparison with the retention time and mass spectrum data of chemical components in the hepatotoxic part of Euodiae Fructus showed that there were 4 prototypes in bile, 15 prototypes in urine and 22 prototypes in feces. By positive ions MSE scanning mode, the data of compounds with mass range of 50~1 200 u were collected. Through comparing with the database with UNIFI software, the retention time of each component, accurate information, primary and secondary mass spectrometry combined with compound cracking rule and existing literature reports, 29 compounds were identified, including 23 prototype components and 6 metabolites. Further, the possible metabolic pathways were deduced by reversely tracing the prototype components of the metabolites. The main metabolic pathways of these components in vivo include glucuronide binding, sulfation, formylation, hydroxylation and demethylation and so on. The metabolism and excretion process in vivowere further revealed by comparing the distribution of prototype components and metabolites in different biological samples. The main existing forms and metabolic pathways of Euodiae Fructus in rat bile, urine and feces were clarified, which provided a valuable reference for revealing the hepatotoxic substances and metabolism law of Euodiae Fructus. At present, the metabolites identification of traditional Chinese medicine is limited to the metabolites with literature reports and prior knowledge. And the results are not very reliable only by analysis of chromatography and mass spectrometry. It is necessary to verify the meaningful metabolites by nuclear magnetic resonance and other methods in the future research to get the exact conclusion.

In order to be able to “see” the information inside the structure about premixed gas of air and gas deflagration flow field in a underground coal mine, to recognize the coupling relationship between shock wave and flame, obstacles accelerating the incentive effects of the flame, the nature of the inert medium flame retardants to suppress deflagration, the super high-speed laser schlieren system was further built on the existing mesoscale explosion shock wave pipeline, and the experimental test scheme of “M”, “Z” and linear optical path arrangement was proposed to replace the traditional pressure flame sensor test method, it provides a new idea to obtain the evolution process of shock wave and the microstructure flow field of flame when gas/air premixed gas is deflagrated.

Thanks to the instruction set architecture (ISA), the software community and the hardware community has been developing independently for years. However, with the advent of multi-core accelerators, the sequential programming model based on the Von Neumann architecture is confronted with troubles. Based on sequential execution model, ISA lacks support for parallel multi-core hardware. Thus, merely using ISA cannot decouple software and hardware. A new program execution model (PXM) is required to accomplish end-to-end compilation from neural networks to interface with sequentially executed programming platforms and parallel multi-core hardware backends, further exploring the optimization opportunities provided by parallel hardware. This paper proposes a codelet model as a new PXM, providing a general abstraction for the process of downloading sequentially executed programs onto parallel hardware. It further decouples the software frontend and hardware backend based on the instruction set. To ensure the reusability of the project, this paper implements the codelet model in the form of a codelet dialect within the MLIR compiler framework proposed by Google. MLIR aims to integrate fragmented compiler ecosystems and improve the reusability of frontend-to-backend integration processes. The codelet model implemented in MLIR in this paper can further enhance the reusability of the MLIR system. [ABSTRACT FROM AUTHOR]

With the increasing use of glyphosate, the accumulation and potential hazards of glyphosate in water bodies have attracted substantial attention. Decreased species richness and coverage of aquatic vegetation in water bodies have been observed in areas where glyphosate has been applied. In this study, the sources, transport and residues of glyphosate in surface water were systematically reviewed. Based on the results of biotoxicity tests of glyphosate on planktonic algae, floating plants, emergent plants and submerged plants, the acute and chronic toxicity of glyphosate on these aquatic photosynthetic organisms was described. The results of toxicity tests showed that aquatic photosynthetic organisms were tolerant to glyphosate and their sensitivity to glyphosate was variable. Submerged plants were more sensitive to glyphosate than planktonic algae, floating plants and emergent plants. On this basis, the toxicity test results of aquatic photosynthetic organisms exposed to glyphosate were summarized and prospected, aiming to provide a scientific basis for the ecological risk assessment of glyphosate on aquatic photosynthetic organisms. [ABSTRACT FROM AUTHOR]

In order to study the inhibition effect of metal mesh on gas explosion, the explosion suppression test device of cylindrical metal mesh in pipeline was designed. The suppression effect of metal mesh on shock wave was studied by comparing the variation of shock wave overpressure under the condition of air-tube experiment and explosion suppression device. The experimental results show that the ratio of length to diameter of cylindrical metal mesh has a great influence on shock wave, and the suppression rate of shock wave is positively correlated with the ratio of length to diameter of cylindrical metal mesh. When the ratio of length to diameter of cylindrical metal mesh is 1/0.2, the increase of elastic potential energy of metal mesh plays a leading role in suppression, and the increase of energy in metal mesh plays a leading role in suppression when the ratio of length to diameter is 2/0.2, 3/0.2.

In order to get the wave system evolution process of gas deflagration suppression by water mist, and obtain the image of the flame structure change when the fine water mist interacts with the flame array, an ultra-high speed laser schlieren system was built on a self-designed mesoscale explosion pipeline to re-understand the mechanism of fine water mist inhibiting gas deflagation from the level of elementary reaction; by analyzing the response time of different systems in the whole experimental system, a reasonable experimental scheme is proposed, and the response time of the flame front arriving at the observation window and the fine water spray injection system are measured. The results show that the time of the flame front arriving at the observation window is 0.113 3 s, and the response time of the fine water spray system is 8.716 ms.

The large diameter pipelines, compared to conventional diameter pipelines, are more likely to cause local buckling instability in case of point load subjected during its installation of submarine pipelines. In the local buckling check on submarine pipelines, the correction method, though, has been given in DNVGL-ST-F101-2017 for point load, the protection of concrete counterweight layer on the pipeline has been ignored, the method is therefore considered to be incompatible with the actual structure of large diameter pipelines, and the calculation results are conservative. With finite element analysis method, the local buckling, which is resulted from point load in the installation process of large diameter submarine pipelines, was systematically studied with actual engineering pipeline structure taken into consideration during analysis. Engineering examples were provided to compare the calculation results from finite element method with those from the DNV standard, allowing supplement to the DNV standard in terms of analysis method. This is of good popularization value for local buckling design of large diameter submarine pipelines.

According to civil aircraft airworthiness standards, the windshield surface should avoid icing or fogging to ensure the pilots visual field. A reasonable heating power should be determined to keep the temperature of windshield. A summarization is made about the critical parameter of windshield heating system design, including heating method, thermal load calculation and control regulation. Based on the related aircraft, the heat transfer processes simulation of windshield is predicted and characteristics of two different heating modes are analyzed by making use of LMS.AMESim. The results demonstrate that the full heating power mode could make a high heating rate and then the windshield will remain a higher temperature, which is good for performance of anti-ice and defogging. Duty ratio heating mode could greatly reduce the thermal shock to windshield, but it also will produce significant impact on upstream equipment because of frequent change of heating power.

As there are factors affecting the detection effect such as small targets and distances in the target video, it is difficult to capture small targets. A multi- spatial hierarchical helmet wearing detection algorithm for small targets is proposed in the article, which will be personalized and improved on the basis of Yolov5s network model. Firstly, a multispatial attention module is designed to consider the effects of spatial features from different perspectives and fuse them to enhance the spatial location relationships of salient features. Secondly, features at multiple spatial scales are fused while combining multiple features in the feature extraction process to adapt to the capture of targets at different spatial levels and improve the detection of small targets. Thirdly, data augmentation is used to improve the generalizability of the dataset to adapt the training targets to more diverse scenarios. Finally, the loss function is optimized to enhance the regression capability and improve the training effect. The experimental results show that the proposed algorithm achieves an average accuracy of 91.5%, significantly reducing the number of missed detections. In addition, the proposed algorithm has been deployed to real construction sites and has shown superior performance in detecting small targets, which is of great value for application. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy of automatic visual inspection of photoelectric products，a kind of prototype of 4SPS/S spherical parallel mechanism (PM) adjustment platform with redundant driving branches is developed. The redundant 4SPS/S PM is of three-rotational degrees of freedom（DOF）around the center of the platform and used for obtaining the image information of the inspected parts from arbitrary angle. Firstly，the kinematics model of the PM is established, and the forward and inverse kinematics equations and Jacobian matrix are derived. Moreover，the singularity is discussed based on Jacobian matrix in terms of rank deficiency, and it is also proved that the redundant drive branch chain can eliminate the singularity in the mechanism. Based on non-redundant decomposition of Jacobian matrix，an evaluation index of force transmissibility suitable for redundantly PM is proposed. Secondly，the influence of the spherical joints layout on kinematical performance of the PM is analyzed，and a set of layout of the spherical joints with large attitude space and good dexterity is obtained. Further，the prototype of spherical parallel detection platform is designed and manufactured. Finally，the distribution of posture space, dexterity and force transfer performance of the prototype in posture space is analyzed and drawn. The results show that the prototype has large rotation space, no internal singularity, high dexterity and force transfer performance, and uniform distribution，which can meet the detection process requirements of photoelectric product.

Aircraft icing detection system is very important to guarantee flight safety. It is also a new problem to assess safety of the aircraft icing detection system. The major function of aircraft icing detection system is analyzed by fault tree analysis method in this paper. The fault tree of icing detection system is built and simplified, and then the minimal cut sets are calculated and discussed here. According to qualitative analysis results, the requirements of icing detection system on aircraft top-level design are suggested. The quantitative analysis results show that the system design can meet the failure rate of icing detection system requirements.

Tea, with a long history of cultivation and widespread planting areas in China, is one of the world's top three non-alcoholic beverages. Guizhou has 466.7 thousand hectares of tea plantations, ranking first class among provinces and regions in China. How to effectively and safely control pests in tea plantations, and to improve tea yield and quality has been a research hotspot. The application of natural enemies to control pests in tea plantations has been widely studied and applied. Cavity-nesting Hymenoptera is an important group of predatory natural enemies in tea plantation ecosystems. In addition, some cavity-nesting Hymenoptera were also pollinators. Thus, this group Hymenoptera plays an unique role in the ecosystem. The artificial trap nest technique provides the nesting tubes for the cavity-nesting Hymenoptera. The harvested tubes were represented the character of the local ecosystem better than other methods since the nested tubes occupied by these Hymenoptera were all actual species living in the given habitats. However, this technique requires plenty of timing and labor input, which leads the limited data available so far. The present dataset was built based on data of cavity-nesting Hymenoptera living in eco-friendly tea plantations in three major tea-producing areas in Guizhou via the artificial trap nest technique. The dataset including information on cavity-nesting Hymenoptera species, quantities, prey ranges, nesting habits, and occurrence patterns, etc., was collected in 2021. It provides species list and dominant species and their basic needing characters, which allows further analyses on their population dynamics and biological control potentials. [ABSTRACT FROM AUTHOR]

According to the structure and layout of less DOF 2-RPU/UPU parallel mechanism,it is overconstraint. The 3-dimensional model of the mechanism is established in Pro/E. By using the screw theory,the DOF analysis of freedom of this mechanism is carried out. The inverse position solution is obtained by mechanism space coordinate transformation. Finally,the workspace of this parallel mechanism is solved by using Simmechanics toolbox in MATLAB.

As landslide-prone areas in remote mountainous areas, it can be challenging to implement tradition landslide monitoring methods such as station observation and satellite remote sensing due to difficulties in power supply and high installation costs. In order to address this issue, a self-powered sensor based on triboelectric nanogenerator (TENG) has been proposed for early warning of mountain landslides. The sensor is designed as a circular tube by utilizing polytetrafluoroethylene (PTFE) and aluminium (Al) as the friction layer of the sensing unit. By harnessing the magnetic forces both inside and outside the tube, the two friction layers are brought into contact and undergo relative sliding along with the movement of the magnet. The working principle of the sensor has been analyzed through COMSOL software simulation, and experiments have been conducted to determine the optimal width of the friction layer material. The novel structure and sensing mechanism of the internal TENG driven by the magnet material result in highly sensitive output signals for this self-powered sensor. At different relative sliding speeds and separation distances, the sensor shows a remarkable sensitivity, with an output voltage of 1.31 V and an output current of 0.17 μA at a relative sliding speed of 0.05 m/s. Laboratory simulations of landslides demonstrate that the TENG-based self-powered energy sensor achieves an output voltage of 2.5 V, effectively detecting the location of landslides. This study expands the development and application of TENG in the field of geological disaster monitoring, and provides a promising solution for the construction of self-powered sensors and self-drive systems. [ABSTRACT FROM AUTHOR]

The spatial and temporal distribution of soil enzymes and their influencing factors were studied in the east wetland of Nanhui, Shanghai in 2019. Based on the differences in the spatial distribution of vegetation, the differences and influencing factors of soil enzymes in four different regions, including the Scirpus mariqueter area, Spartina alterniflora area, the mixed vegetation area of Spartina alterniflora area and Scirpus mariqueter area, and the area of bare tidal flats, were studied. The results are as follows: In the Dongtan wetland of Nanhui, the activities of different soil enzymes varied among different vegetation types, and the order of urease activity was Scirpus mariqueter area > bare beach area > Spartina alterniflora area > mixed area, the order of soil invertase activity was Scirpus mariqueter area > Spartina alterniflora area > mixed area > bare beach area, the order of alkaline phosphatase activity was bare beach area > Scirpus mariqueter area > mixed area > Spartina alterniflora area, and the order of catalase activity was mixed area > Scirpus mariqueter area > Spartina alterniflora area > bare beach area; The activities of urease and invertase in the mixed vegetation area were lower than those in the single vegetation area, and the invasion of Spartina alterniflora reduced the activities of urease and invertase, thereby reducing the soil fertility of the Dongtan wetland of Scirpus mariqueter; The activities of soil enzymes in different vegetation types were influenced by different environmental factors, and the vegetation type determined the soil fertility, which in turn affected the enzyme activity. [ABSTRACT FROM AUTHOR]

Photoacoustic imaging and laser induced breakdown spectroscopy are two technologies that have been developed very rapidly in the imaging field in recent years, and have great potential in medical imaging. When the laser irradiates the tissue, both the photoacoustic signals and plasma are generated on the surface of the tissue. The photoacoustic signal carries the characteristic information of light absorption in the tissue, and the characteristic spectrum of the plasma can also trace the element information in the tissue. This paper summarizes the research background and imaging principle of the two technologies, and further demonstrates the possibility of a combination of the two technologies by analyzing the photoacoustic imaging and LIBS imaging modes, and introduces their applications in the fields of pathological section imaging and tissue metal element tracing. Finally, we discuss and prospect the bimodal imaging system combining the two technologies, which is expected to play an important role in the field of medical diagnosis and imaging. [ABSTRACT FROM AUTHOR]

The flotation behavior of spodumene and silicate minerals, such as feldspar and quartz, and the surface components dissolution behavior were studied by mechanical stirring test, flotation test and the ICP-AES detection. The results show that the flotation recovery of spodumene increased, but the recovery of feldspar and quartz basically unchanged, then the flotation separation efficiency of artificial mixed ore is significantly improved with the increase of stirring speed and stirring time. The dissolution amount of Si component on minarals surface is spodumene >feldspar>quartz, and the dissolution amount of Si component is also greater than that of Li and Al for spodumene. The flotation rate constant of spodumene after the pretreatment is directly proportional to the relative dissolution rate of surface Si components, which means that the dissolution rate of surface Si components is the key factor to determine the flotation rate of spodumene. The massive dissolution of Si components from spodumene leads to the increase of the relative content of Al and Li components on its surface, and promotes the adsorption of oleate and the flotation of spodumene. [ABSTRACT FROM AUTHOR]

:By taking the turbulence effect and pad deformation of large tilting pad journal bearings into consideration, a three-dimensional thermo - elastic hydrodynamic lubrication (TEHD) model was built based on the joint simulation of COMSOL and MATLAB.In the model, the modified Reynolds equation,energy equation and heat conduction equation were calculated by using the physics field module partial differential equation (PDE) of COMSOL. The deformation calculation of pad was realized by the thermal stress physical field module in COMSOL. The coupling of multi physical fields and the control of calculation process were realized by MATLAB.Based on the model,the influence of the pad arc length, nominal clearance, pivot offset and axial width on the performance of tilting pad journal bearing was investigated.The results show that when the arc length or axial width of the pad increase, the oil film thickness increases and the pad surface temperature decreases,however,the total friction power loss increases. When the radial clearance increases, the oil film thickness increases,the pad surface temperature decreases and the friction power consumption decreases slightly. When the pivot offset increases, the change trend of the two lower pads is opposite, and the total bearing capacity and friction power loss increase slightly. This study provides valuable reference for the optimal design of tilting pad journal bearings. [ABSTRACT FROM AUTHOR]

Video supervision system was designed according to characteristics of working face of thin seam, and overall design and design of hardware and software were introduced. The system achieves real-time monitoring of working face of thin seam, and has stable performance, clear images, smooth video and short communication delay, which will greatly improve mining efficiency and reduce labor intensity.

BACKGROUND: Polysaccharide-based biomaterials are hydrophilic and can promote cell adhesion, proliferation and differentiation. They can not only effectively prevent against oral diseases, but also promote the regeneration of periodontal ligament, enamel and alveolar bone. OBJECTIVE: To review the application of chitosan-based polysaccharide biomaterial in many oral diseases. METHODS: A computer-based online search of PubMed and CNKI databases was performed to retrieve papers regarding application of chitosan-based polysaccharide biomaterial in oral diseases with the search terms "polysaccharide (chitosan or hyaluronic acid or cellulose) and oral disease" in Chinese and English. RESULTS AND CONCLUSION: Chitosan-based polysaccharide biomaterial can be used In periodontal, oral and maxillofacial systems, aesthetic restoration, orthodontics and other fields because chitosan has aminoglucan-like structure and the biological functions of cellulose and collagen, and possesses good biocompatibility. In the early stage of the disease, polysaccharide substance can prevent the occurrence of oral diseases and inhibit the accumulation of plaque microorganisms. During the repair period of the disease, polysaccharide substance itself can promote cell proliferation and differentiation, and has a good antibacterial effect. With the help of the specific efficacy of polysaccharide biomaterials, polysaccharide can effectively exert adhesion, antibacterial and regeneration effects. In addition, polysaccharides can also be digested to monosaccharides in vivo, which is good for tissue repair. In the future therapeutic field, the degradability, biocompatibility, easy availability, specific network structure, surface charge and other characteristics of the polysaccharide can be better utilized to expand the application range. [ABSTRACT FROM AUTHOR]

Histograms of dominant orientations (HDO) is a simple local image descriptor with fine performance. However, the original HDO feature description has no rotation invariance. This paper presents a rotation-invariant HDO feature description. To acquire the rotation invariant feature, i.e., dominant orientation and the coherent, by RGT (radial gradient transform), the structure tensor of given location is calculated in a circular neighborhood. Then, to enhance distinctiveness, space pooling operation is implemented with multi-sector division. Test results in public MIT faces data show that if the image does not rotate, the proposed method and the original HDO descriptor almost have the same accuracy (92.10%), while, if the image rotates, the accuracy of the improved HDO descriptor is higher than that of the original HDO by 10.36%. In addition, in the experiments of pedestrians, synthetic rotated palms and faces detections, our method is obviously superior to its original one. Moreover, the proposed method shows better recognition accuracy than most recent anti-rotation descriptors in public 53Objects, ZuBuD and Kentuky image datasets. [ABSTRACT FROM AUTHOR]

This paper proposed a novel representation mode based on binary-symbol for degeneracy in undirected graph and directed graph based on DNA sequences. This method transferred the coding process for four bases to the moving process of elements which composed DNA sequences on the rectangular coordinates. It used two different symbols to express overlapping elements in the kind of graphical representation. Graphical curve could not overlap under this mechanism. One DNA sequence had unique graphical representation and vice verse. Degeneracy in undirected graph and directed graph could be decreased in some examples by this method. As a tool, codes mode based on artificial metabolic system could be used for different DNA sequences comparison. It researched similarity in DNA sequences in different animals based on metabolic intermediate. From the experiments it can conclude that the parameter can illustrate similarity degree among different animals and it is convenient method for discussing DNA sequences feature. [ABSTRACT FROM AUTHOR]

In order to improve the catalytic performance, the wool supported copper-iron bimetal complexes were prepared by adding copper ion in the wool supported iron conplex, and the effect of copper ion on the catalytic performance of wool supported copper-iron bimetal complexes was examined. Then the pseudo first-order kinetic model was employed to fit the experimental data. Finally, the dyeing wastewater after decoloration was reused for the coloration of cotton fabrics by reactive dyes. The results indicated that wool supported copper -iron bimetal complexes exhibited the higher catalytic performance in the presence of copper ions. The reactive dyes exhibited good dyeing capacity for cotton fabrics in the dyeing wastewater after decoloration . [ABSTRACT FROM AUTHOR]