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The battlefield changes rapidly in information warfare. The battlefield situation data presents massive and diversified characteristics, which makes it increasingly difficult to identify the operational intent of air targets based on expert experience. In combination with the current state-of-the-art intelligent methods, the Transformer model is studied and introduced into the field of air target intent recognition for the first time, and a new intent recognition method temporal-spatial transformer(TST) is designed, which can effectively mine the deep feature information in the temporal and spatial domains of battlefield situational data to improve the accuracy of air target combat intention recognition. In addition, a comparative study of the four currently advanced neural network intention recognition methods shows that TST achieved outstanding performance in all indicators and outperformed all compared neural network models. TST method not only has excellent accuracy but also extremely fast convergence rate, which allows it to quickly capture key information from battlefield situation data for intention recognition.

Objective To evaluate the efficacy of selective curettage when apical lesions are adjacent or involved to important structures in endodontic microsurgery (EMS). Methods A total of 264 patients who underwent EMS in the Department of Endodontics, The Affiliated Stomatological Hospital of Nanjing Medical University from January 2021 to January 2023 were selected as the research subjects. The cases of EMS were divided into selective curettage group (SC-EMS) and conventional curettage group (C-EMS). In SC-EMS group, patients with apical lesions involving or adjacent to important structures (mental foramen, mandibular neural tube, nasopalatine neural canal, maxillary sinus, nasal base and adjacent vital pulp teeth) were included, and the adjacent areas around important structures were selectively cureted. In C-EMS group, patients with apical lesions adjacent to important structures were treated with conventional apical curettage. The postoperative follow-up was 12 months, and the postoperative symptoms and imaging examinations of the patients were observed, and the efficacy was evaluated. The failure cases were examined after tooth extraction and preoperative pathological review to analyze the causes of failure. Results The success rate of SC-EMS group is 90.2%, and the success rate of C-EMS group is 95.4%. The rate of success in C-EMS group was higher, but there was no statistical difference between the two groups(P>0.05). Root fracture is the important causes for the failure of the two groups. There were 6 cases of short-term discomfort and 2 cases of long-term discomfort after SC-EMS. The C-EMS group didn’t meet any short-term or long-term discomfort case. Conclusion Selective curettage has no significant effect on the success rate of EMS surgery, and is an effective method to protect important structures during surgery. Short-term discomfort may occur after surgery, and irreversible pulp damage of adjacent teeth occurs in a few cases.

High pressure, narrow mud window and well control risks are common challenges encountered in High Temperature High Pressure (HTHP) wells. Reducing the complexity of incidents and ensuring the safety while drilling in high pressure and narrow mud window wells are technical challenges which need to be urgently solved. Managed Pressure Drilling (MPD) effectively solves the challenges of safety drilling under narrow safe pressure margin by establishing a trapped pressure environment to control the annular pressure profile. However, the risk of down hole pressure fluctuation still exists due to the switch of circulation from downhole circulation to surface circulation during connection in MPD mode. Continuous Circulation System (CCS) is usually used to maintain the full cycle circulation during connection, but the system is also not able to precisely predict the formation pressure and immediately adjust the bottom hole pressure. In this research, the MPD technology combined with the Eni circulating device (e-cdTM) system is presented to overcome the shortages of MPD and CCS technologies when they are individually applied in high temperature high pressure wells. The application of this combined practice in the Obiafu-X well located in Block OML-61, Delta, Nigeria enabled to avoid the occurrence of various non-production time accidents and improved the drilling efficiency. The combination of MPD technology with e-cdTM system in HTHP wells can therefore provide an advantageous reference in the domestic HTHP drilling industry.

The backflow and back-pressure propagation induced in a pulse detonation combustor (PDC) are the main factor in causing the thrust losses of a pulse detonation engine. In order to suppression the backflow propagation of a PDC, the aero-dynamic suppression strategy was implemented in this work. A total of ten isolators composed of different geometries were designed. A single-pulse detonation experiment was conducted by using the stoichiometric ethylene/enriched-oxygen mixture. It is shown that when the back-pressure has propagated about 0.86 the length of PDC, the propagation speeds and the pecks of the back-pressure in the isolator, which composed of the Venturi tube (V) and a long tube with 1.5 times diameter of the PDC, can be reduced by 10% and 20%, respectively, comparing with the base isolator. Comparing with the isolators that without the Tesla valve (T), the propagation speed of the back-pressure in the cases with the Tesla valve can be additionally reduced above 27.3%. Comparing with the isolators that without the slit (S), the peaks of the back-pressure in the cases with the slit can be decreased about 25%. The average decay rate of the back-pressure peaks can be highly increased if the cone (C) is introduced. It is found that the CVST-type isolator is the optimal. Comparing with the base isolator, the backpressure propagated in the CVST-type isolator can decrease about 50% and 40.5% of propagation speed and pressure peaks, respectively, and can increase the average decay rate of the back-pressure peaks by a factor of two.

In the window function spectrum of the low signal-to-noise ratio photon Doppler signal after the short-time Fourier transform, the weak beat frequency cannot be obtained by extracting the maximum amplitude spectrum frequency of each window because the amplitude of the noise spectrum exceeds the weak beat frequency. In this article, the value of the beat frequency is first estimated by the Kalman filter. Then, a multiple analytical bandpass filter is constructed to refine the spectrum of the high noise signal with the value of the beat frequency estimate as the spectrum band center. This technique extracts only the beat frequencies from the narrowband refinement spectrum by removing the interference spectrum band range. We use this technique to process the photon Doppler signals from the tiny high-speed flying fragments explosion experiment. After data processing, the beat frequency value heavily affected by high-frequency noise can reduce the error by up to 64.9%. The beat frequency value of the low noise signal can be accurate to 106 Hz, equivalent to 0.775 m/s after velocity demodulation. This method fully considers the positioning and protection of the beat frequency characteristics. It makes weak beat frequencies more obvious in the refined narrowband spectrum without changing the signal amplitude. This article describes a method for extracting the weak beat frequency of the photon Doppler signal or a signal optimization algorithm for needing high-precision beat frequencies in a test environment.

Although traditional machine learning based methods for predicting mine internal caused fire have certain predictive capabilities, they cannot effectively capture global dependencies between complex multivariate data, resulting in low prediction precision. In order to solve the above problems, a transformer based time series prediction method for mine internal caused fire is proposed. Firstly, the Hampel filter and Lagrange interpolation method are used to detect outliers and fill in missing values in the data. Secondly, the self attention mechanism of Transformer is utilized to extract features and predict trends from time series data. Finally, by adjusting the size and step size of the sliding window, the model is trained in different time dimensions at different time steps and prediction lengths. Combining gas analysis method, the iconic gases generated by mine fires (CO, O2, N2, CO2, C2H2, C2H4, C2H6) are used as input variables for the model, with CO as the target variable for model output and O2, N2, CO2, C2H2, C2H4, C2H6 as covariates for model input. Selecting the bundle data of S1206 return air corner fire warning in Ningtiaota Coal Mine of Shanmei Coal Group for experimental verification, the results show the following points. ① Univariate prediction and multivariate prediction of CO show that multivariate prediction has higher prediction precision than univariate prediction, indicating that multivariate prediction can improve the prediction precision of the model by capturing the correlation between sequences. ② When the time step is fixed, the prediction precision of the Transformer based mine internal caused fire prediction model decreases with the increase of prediction length. When the prediction length is fixed, the prediction precision of the model improves with the increase of time step. ③ The prediction accuracy of the Transformer algorithm is improved by 7.1%-12.6% and 20.9%-24.9% over the long short-term memory (LSTM) algorithm and recurrent neural network (RNN) algorithm, respectively.

The Total Focusing Method (TFM) technique is an advanced Non-Destructive Testing (NDT) Ultrasonic Testing (UT) technique. It is usually used together with special acquisition configurations such as Full Matrix Capture (FMC) or Plane Wave Imaging (PWI) and can supply synthetic post-processing results based on a quantity of ultrasonic signals. It is believed that it will accelerate the UT technique revolution toward the artificial intelligence era. Compared to the conventional UT technique, or even advanced UT techniques, such like Time of Flight Diffraction (TOFD) and Phased Array (PA) techniques, this advanced UT technique is well known for its easy-to-interpret and high-resolution representative images. For these reasons, it is used more and more in the flaw sizing and characterization assessment. Following the publication of the standard ISO 23864, TFM technique become a member among all standardized weld inspection techniques. This article presents some related study results toward a code-compliant weld inspection regarding the related standards, dealing especially with the sensitivity calibration which is a key point for the applicability of amplitude-based acceptance criteria.

The flexible DC transmission system is connected to the island grid， so the control mode needs to be changed according to the AC topology. In the process of grid-connected and island operation conversion， there are phenomena such as excessive disturbance， high frequency instability and so on. Firstly， the transition method from grid-connected operation to island operation is put forward. The speed and accuracy of the transition from grid-connected operation to island operation of flexible DC system can be improved through the combination of electric quantity and switching quantity. Then， a simple high-frequency model of the flexible DC system is established to analyze the causes of high-frequency component during the transition from grid-connected operation to island operation. Combined with the high-frequency instability of the transition from grid-connected operation to island operation， the optimal logic of the transition from grid-connected operation to island operation and the island open-loop control strategy are proposed to improve the stability of the system. Thirdly， the transition strategy of island operation to grid-connected operation is designed based on the load forecasting of valve side current to avoid the overcurrent trip during the process from island operation to grid-connected operation. Finally， the effectiveness and correctness of the proposed strategy are verified by the online simulation model combining the control protection devices in actual engineering.

Natural silk fiber derived from the Bombyx mori (B. mori) silkworm has long been used as a luxury raw material in textile industry because of its shimmering appearance and durability, and as surgical suture for its high strength and flexibility. Regenerated silk fibroin, as the main protein extracted from the cocoons of the B. mori silkworm, recently has gained considerable attention due to its outstanding properties, including facile processability, superior biocompatibility, controllable biodegradation, and versatile functionalization. Tremendous effort has been made to fabricate silk fibroin into various promising materials with controlled structural and functional characteristics for advanced utilities in a multitude of biomedical applications, flexible optics, electronics devices, and filtration systems. Herein, reverse engineered silk fibroin extraction methods are reviewed, recent advances in extraction techniques are discussed. Fabrication methods of silk fibroin materials in various formats are also addressed in detail; in particular, progress in new fabrication technologies is presented. Attractive applications of silk fibroin-based materials are then summarized and highlighted. The challenges faced by current approaches in production of silk fibroin-based materials and future directions acquired for pushing these favorable materials further toward above mentioned applications are further elaborated.

【Objective】 Surface water evaporation (Ep) in greenhouse is often used as a reference in irrigation management. The purpose of this paper is to present a model to estimate it. 【Method】 The model was derived based on meteorological data and pan-evaporation measured from March to July in 2020 and 2022. The relationship between Ep and meteorological data was analyzed using the principal component method, from which a multiple linear regression model was developed to estimate Ep. 【Result】 Ep increased as time elapsed, with its average increasing from the range of 1.84~1.94 mm in March to the range of 3.77~5.15 mm in June in both 2020 and 2022. Ep was influenced by radiation and relative humidity the most. Photosynthetically active radiation had the highest correlation with Ep, with their correlation coefficient being 0.852 (P

BACKGROUND Black shales are mostly developed in special periods in geological history. They not only record the evolution characteristics of paleoenvironment, paleoclimate and paleontology, but also are carriers of organic matter, oil and gas and various metal deposits. Taking the black shale of the Lower Cambrian Niutitang Formation in Guizhou as an example, it not only shows the extraordinary enrichment of V, Ni and other metal elements, forming vanadium ore and nickel-molybdenum ore, but is also rich in organic matter, with TOC content of 0.7%-14.6% (average 5.2%). At present, the co-enrichment mechanism of metal elements Ni, V and organic matter is still unclear, but organic matter plays an important role in the enrichment, migration and transformation of metal ions. OBJECTIVES To understand the co-enrichment mechanism of organic matter and metal elements by exploring the effect of metal elements on the structure of organic matter. METHODS Take two groups of 50mL polypropylene centrifuge tubes A and B, and add 5g of humin to each centrifuge tube. Then add 20mL of Ni single element standard solution to the group A centrifuge tube, and 20mL of V single element standard solution to the group B centrifuge tube. Place the centrifuge tube in a constant temperature oscillator for 24h with the temperature of 298K and the speed of 220r/min. After standing for 24h, the filtered solid part is placed in a 50mL beaker and dried. The dried samples (numbered as HM-Ni and HM-V) and the original humin sample (numbered HM) are analyzed by element analyzer, X-ray photoelectron spectroscopy (XPS) and solid-state nuclear magnetic resonance carbon spectroscopy (13C-NMR). RESULTS The results show that the elemental composition of humin is mainly C and O. After the action of Ni and V metal solutions, the relative contents of O and S elements in humin decrease, and the relative contents of C and N elements increase. The ratio of H/C and O/C atoms is HM>HM-V>HM-Ni. XPS test shows that the C element on the surface of humin is mainly in the form of aromatic carbon, while the O element is mainly in the form of hydroxyl oxygen. For C with different occurrence forms, the influence trend of Ni and V metal solutions on them is the same, which reduces aromatic carbon, hydroxyl carbon and carbon-based carbon, and mainly destroys aromatic carbon (C—C/C—H) single bonds. For O with different occurrence forms, the Ni metal solution reduces hydroxyl oxygen and carboxyl oxygen, which makes the hydrogen-enriched and oxygen-enriched functional groups prolapse; the V metal solution reduces carbonyl oxygen and carboxyl oxygen, which destroys the carbonyl double bond (C=O). Solid-state nuclear magnetic resonance carbon spectroscopy (13C-NMR) tests show that the action of Ni metal solution can reduce the relative contents of bridged aromatic carbon (far B), oxygen-connected aromatic carbon (far P), carbonyl carbon (fa O), methyl and quaternary carbon (fal *), as well as methylene and methine carbon (fal H); V metal solution can reduce the relative contents of protonated aromatic carbon (far H), bridged aromatic carbon (far B), oxygen-connected aromatic carbon (far P), carbonyl carbon (fa O), methyl and quaternary carbon (fal *), as well as methylene and methine carbon (fal H). Both metal solutions can make the O-enriched and H-enriched functional groups in oxygen-linked aromatic carbon (far P) and bridged aromatic carbon (far B) prolapse from the aromatic ring, shorten the lipid chain length in humin, reduce the stability of organic carbon, reduce the content of active organic carbon and reduce the degree of hydrophobicity. CONCLUSIONS Through comparative analysis, it is shown that humin has a certain oxidation ability to Ni and V metal elements. After the action of the two metal solutions, the occurrence morphology of C and O elements in humin can be changed. Ni metal solution mainly affects the aliphatic carbon structure, while V metal solution mainly affects the aromatic carbon structure.

The expansion of local legislative authority has prompted the introduction of various local regulations, which have promoted local governance in various places. However, the formulation of local legislation suffers from problems such as singularity and fragmentation, and its informatization has not kept pace with the development of artificial intelligence. In order to study the application of artificial intelligence in local legislation, this paper applies artificial intelligence to the intelligent screening of legislative solicitations and the intelligent review of draft regulations through the study of generative adversarial networks and their optimization models. Facing legislative opinions with large amounts of data and complex text, the text recognition rate of AI reaches 98.24%, the success rate of similar opinion de-duplication is 84.69%, and the success rate of classifying opinions applying to different fields and different legal articles is 79.09%. Artificial intelligence can also filter out 71.13% of invalid opinions. In reviewing draft regulations, the success rate of artificial intelligence in judging whether it conflicts with the higher law is 83.01%, and the success rate of judging whether it conflicts with the same law is 80.64%. Artificial intelligence has a natural advantage in assisting local legislators to deal with a large amount of repetitive paperwork, which can effectively improve the efficiency of local legislation. Using artificial intelligence to assist local legislation can help local legislation make great progress and development to maintain local stability better and promote local development.

Objective: We aimed to evaluate the feasibility and safety of his-bundle pacing (HBP) and left bundle branch pacing (LBBP) in patients with hypertrophic cardiomyopathy (HCM) and heart failure (HF). Methods: Patients with HF and interventricular septal thickness (IVST) ≥ 13 mm resulted from HCM, who accepted conduction system pacing (CSP) with a percentage of ventricular pacing > 40% from May 2018 to April 2022 were consecutively enrolled in our center. LBBP was preferred and HBP was the alternative therapy unless IVST ≥ 16 mm or LBBP failed, whereas LBBP would be the alternative therapy if HBP failed in patients with IVST ≥ 16 mm. All patients were followed up for at least one year. Data including clinical, echocardiographic parameters and electrocardiogram measurements, were collected and evaluated in patients with and without left ventricular ejection fraction (LVEF)

The performance software of a domestic civil aircraft used by an airline for many years can obtain satisfactory results in the accuracy of obstacle limited weight calculation, but the calculation time is long. The optimization model is established by comparing the calculation results and efficiency of the two models of the minimum acceleration height method and the maximum acceleration height method. The obstacle limited weight, acceleration height and calculation time of the two models under different obstacles and different wind speeds are calculated and analyzed. The results show that the calculation results of obstacle limited weight and acceleration height of the two models are basically the same; When there is no obstacle, whether there is wind or not, the calculation time can be reduced by 25% using the optimization model with the minimum acceleration height compared with the original model with the maximum acceleration height; When there are obstacles and there is no wind, the calculation time can be reduced by more than 78% by using the optimization model with minimum acceleration height,and when there is wind, the calculation time can be reduced by more than 75%. The model with the minimum acceleration height can take account of both accuracy and efficiency.

Avec le vieillissement des installations industrielles, la recherche d’endommagements par corrosion au droit de zones inaccessibles (notamment sous supportages de tuyauterie) par les méthodes conventionnelles de CND attire de plus en plus l'attention. L'objectif principal étant d'évaluer la conformité de l'épaisseur résiduelle en regard de l'épaisseur de calcul des composants contrôlés. Les solutions actuelles sont apportées principalement par des techniques d’examen ultrasonores conventionnelles, multiéléments ou EMAT, à moyenne et longue portée, telles que la technique Multibonds, la technique CHIME et les techniques d’ondes guidées, avec une incertitude significative sur la précision d'évaluation de l’extension en profondeur des zones de corrosion détectées. ONET Technologies a réalisé nombreuses prestations de contrôle de zones sous supportage de tuyauteries à géométries complexes en milieux hostiles. Plus de 10 années d’expériences sur le terrain nous ont permis de développer une solution de contrôle novatrice, intégrant notamment, le développement d’un scanner motorisé dédié, l’amélioration des performances de détection et de quantification par l’utilisation combinée de différentes techniques ultrasonores, l’étude de nouveaux algorithmes d'analyse et le développement d’un outil informatique permettant d’accroitre la précision de mesure et de réduire l’impact du facteur humain. Ce nouveau produit développé par ONET dans le cadre d’un projet de R&D subventionné par France Relance permet une quantification et un suivi en service beaucoup plus précis de l'épaisseur résiduelle minimale des zones de corrosion détectées sous la forme d’une profilométrie de la perte d’épaisseur en zone affectée avec ses incertitudes associées. Dans cet article nous allons présenter les résultats de nos développements.

New equipment and technical applications on distribution networks demonstrate a tendency of physical data integration， and distribution network morphology is also changing rapidly. Therefore， adaptability testing and verification on new equipment and technology are required to improve distribution network reliability and resource scheduling capability. To this end， the construction and application of real tests for intelligent distribution networks are studied. Firstly， the purpose of the platform and system composition are analyzed. Secondly， the specific implementation methods of power， neutral point test platform， medium-voltage AC/DC architecture test platform， distribution cables， channel test platform， and other platforms are introduced. Finally， three major test scenarios are designed： earthing test 10 kV primary and secondary fusion circuit breaker， functional assessment test on intelligent fully automatic FA， and fault sensing test on low-voltage transformer area. The true test platform for intelligent distribution networks is applied to make up for the deficiency of the traditional testing methods for distribution networks and equipment.

ALK fusion genes are diverse. Approximately 30 different ALK fusion protein partners have been described previously, and some of these fusion proteins have been reported to be effective against ALK-tyrosine kinase inhibitor (TKI). ALK rearrangements often occur at a common breakpoint in exon 20 of the genome. SLC8A1-ALK, a novel fusion protein partner, comes from exon 2 of the SLC8A1 gene rearranged with exon 20 of the ALK gene. Here, we reported a patient with advanced lung adenocarcinoma harboring a SLC8A1-ALK fusion who benefited from first-line treatment with alectinib. After 2 months of taking alectinib, the targeted lung lesions and intrahepatic metastases regressed significantly. To date, the patient has achieved nearly 1 year of progression-free survival while taking the drug. Given the diversity of ALK fusion genes and the different efficacy of ALK-TKIs, we believe that this case report has an important clinical reference.

A life cycle standardized assessment module of energy-saving and carbon reduction is established based on the current road cost management software. The assessment module combines the domestic road material consumption quota and the main LCA database CLCD in China. Quantitative energy-saving and carbon reduction benefits of material and technical alternative measures could be calculated autocratically. Empirical project data shows that reducing concrete, reducing mixing temperature and reusing material of the old road are essential measures. It is possible to reduce carbon by 22-28% and save energy by 45-50%.

As a major producer of oil and gas, China has historically adopted a variety of different approaches to managing its overall oil and gas supply chain. It also incorporates decisions and forecasts of trends in the overall petroleum supply chain in the context of existing domestic and international societal trends, such as the impact of national policies and the supply chains of China’s domestic petrochemical companies in the context of Sinopec’s past annual reports and assessments and recommendations for sustainable supply chains. This article uses the case study of Sinopec, a major Chinese chemical company, to provide statistics on the domestic market context and to propose and discuss risk management and sustainable supply chains for the company’s supply chain, as well as quantitative analysis to forecast and analyze China’s domestic oil consumption, with case studies and data on all indicators, and to show the impact of plans and trends on the chemical supply chain over time. The implications and trends of developing trends in the chemical supply chain are presented, and conclusions and final recommendations are drawn.

Gastrointestinal (GI) complications of diabetes mellitus (DM) significantly impact on patients’ quality of life. Enteric glial cells (EGC) are the key cell type of enteric nervous system (ENS), which contributes to the destruction of gut homeostasis in DM. Circular RNAs (circRNAs) are a novel type of RNAs abundant in the eukaryotic transcriptome, which form covalently closed continuous loops. In this study, the contribution of circRNAs to EGC damage in DM is investigated. Transcriptome sequencing analysis and functional study show that circVPS13A is significantly down-regulated in hyperglycemia-treated EGC, and circVPS13A overexpression attenuates EGC damage in both in vitro and in vivo DM models. In vitro mechanistic study using dual-luciferase reporter assay, affinity-isolation assay, fluorescence in situ hybridization (FISH) and immunostaining analysis identify that circVPS13A exerts its protective effect by sponging miR-182 and then up-regulates glial cell line-derived neurotrophic factor (GDNF) expression. In addition, in vivo study confirms that the circVPS13A-miR-182-GDNF network regulation can attenuate hyperglycemia-induced EGC damage of duodenum in streptozotocine (STZ)-induced DM mice. The findings of this study may provide novel insights into the protective role of circVPS13A in DM-associated EGC damage and clues for the development of new therapeutic approaches for the prevention of GI complications of DM.

Objective To investigate the protective effect of idebenone (IDBN) on hippocampal neuron injury in epileptic rats and its mechanism. Methods Forty-eight Wistar rats were randomly divided into normal control group, IDBN prevention group (prevention group), epilepsy group, IDBN 25, 50 and 100 mg groups. Behavioral changes of rats in different treatment groups before and after treatment with IDBN were observed. The activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and the content of malondialdehyde (MDA) in hippocampal were detected. The ultrastructural changes of hippocampal neurons and mitochondria were observed. Results The expression levels of SOD, GSH-Px and MDA in different treatment groups were significantly different (P = 0.000, for all). The activity of SOD and GSH-Px was the highest and the content of MDA was the lowest in IDBN 100 mg group. The activity of SOD and GSH-Px in IDBN 100 mg group were higher than those in epilepsy group (P = 0.000, 0.000), IDBN 25 mg group (P = 0.000, 0.000) and 50 mg group (P = 0.004, 0.005), while the content of MDA was lower than that in epilepsy group (P = 0.000), IDBN 25 mg group (P = 0.000) and 50 mg group (P = 0.002). Compared with normal control group and prevention group, hippocampal neurons in epilepsy group showed different degrees of damage, which was relieved after treatment with IDBN and gradually decreased with the increase of dose. In epilepsy group, the mitochondrial structure of hippocampal neurons was damaged obviously, with deformation and swelling, and some mitochondria were vacuolated. After treatment with IDBN, the damage was relieved, and the 100 mg group had the least damage. Conclusions IDBN can protect hippocampal neuron structure and function by inhibiting oxidative stress injury in epileptic rats.

In order to achieve the fault through of voltage source converter-based high voltage direct current (VSC-HVDC)system during alternating current (AC) system asymmetric faults and keep stability of the impedance at steadystate, a timely switch fault through method for VSC-HVDC system is proposed in this paper. Firstly, the positive and neg-ative sequence control of VSC-HVDC system and the effect of decomposition algorithm with 1/4 cycle delay on the impedance of VSC-HVDC system are analyzed. The high frequency impedance model on the AC side of VSC-HVDC system established. Then, on this basis, the AC fault is judged by the steady-state quantity and ab-rupt quantity of negative sequence voltage. In the steady state, the full sequence current control without positive and negative sequence decomposition is used to reduce the periodic fluctuation of the VSC-HVDC system impedance. In the transient state of fault, the negative sequence current control is superimposed to suppress the negative sequence fault current and realize the continuous operation of the system. Finally, model of VSC-HVDC system is developed in PSCAD/EMTDC to prove the validity of the proposed control method.

Objective To investigate the effects of intravascular hypothermia on intracranial pressure (ICP) and cerebral hemodynamics in patients with severe traumatic brain injury (sTBI) after standard decompression craniectomy. Methods A retrospective cohort study was carried out on 82 sTBI patients admitted to Chongqing Emergency Medical Center from January 2019 to March 2021. All patients received standard decompressive craniectomy (ICP>20 mmHg). Among them, 38 patients were treated with intravascular hypothermia as the experimental group, and 44 patients were not as the control group. The effects of intravascular hypothermia on ICP, cerebral hemodynamics, and brain injury markers were analyzed, and the results were compared between the 2 groups. Glasgow coma scale was used to evaluate the prognosis. Results ICP in the experimental group began to decrease after hypothermia treatment, and decreased to less than 20 mmHg in 12 h later. In the control group, ICP fluctuated greatly, and decreased to below 20 mmHg in 18 h later. At 22 and 24 h after operation, ICP was more significantly decreased in the experimental group than the control group (P < 0.05). At 1 week after operation, the peak systolic blood flow velocity and average blood flow velocity of middle cerebral artery were increased, the pulsatile index was decreased, the serum contents of glial fibrillary acidic protein, S-100β and neuron-specific enolase were decreased in the 2 groups. And above changes were more obviously in the experimental group than the control group (all P < 0.05). In 6 months after operation, 22 cases (57.90%) in the experimental group and 15 cases (34.09%) in the control group achieved a good prognosis, with significant difference between them (P=0.042). Conclusion Intravascular hypothermia can reduce ICP and improve cerebral hemodynamics in sTBI patients after standard decompression craniectomy.

Among the different nanostructures that have been demonstrated as promising materials for various applications, three–dimensional (3D) nanostructures have attracted significant attention as building blocks for constructing high-performance nanodevices because of their unusual mechanical, electrical, thermal, optical, and magnetic properties arising from their novel size effects and abundant active catalytic/reactive sites due to the high specific surface area. Considerable research efforts have been devoted to designing, fabricating, and evaluating 3D nanostructures for applications, including structural composites, electronics, photonics, biomedical engineering, and energy. This review provides an overview of the nanofabrication strategies that have been developed to fabricate 3D functional architectures with exquisite control over their morphology at the nanoscale. The pros and cons of the typical synthetic methods and experimental protocols are reviewed and outlined. Future challenges of fabrication of 3D nanostructured materials are also discussed to further advance current nanoscience and nanotechnology.

Objective: This study aimed to realize the high-value utilization of biological active ingredients and anti-inflammatory peptides from the Pinctada martensii meat. Methods: The hydrolysis process of the P. martensii meat was optimized by single factor test and response surface test with degree of hydrolysis (DH) as the index. The amino acid composition and anti-inflammatory activity of P. martensii meat hydrolysate peptides were evaluated and analyzed. Results: The results showed that neutral protease was the optimal enzyme, and the optimal hydrolysis conditions were solid-liquid ratio 1∶1 (g/mL), temperature 46.3 ℃, hydrolysis time 1.4 h, and substrate ratio 0.3%. The hydrolysis degree was 22.88%, which was not significantly different from the theoretical value, and the regression model was reliable. The hydrolysates including 19.84% of essential amino acids, 21.19% of hydrophobic amino acids and 10.46% of positively charged amino acids. In LPS induced RAW264.7 anti-inflammatory model of mouse macrophages, the hydrolyzed peptide of P. martensii had no cytotoxicity and was beneficial to the proliferation of macrophages in the mass concentration range of 0~4.0 mg/mL. At the mass concentration of 2.0 mg/mL, hydrolyzed peptide could effectively inhibit the production of NO and inflammatory cytokines TNF-α, IL-6 and IL-1β; the inhibition rate of NO, TNF-α, IL-6 and IL-1β was 70.00%, 83.01%, 85.04% and 83.11%, respectively. Conclusion: Hydrolytic peptide of P. martensii has a complete range of amino acids, which can effectively inhibit the production of NO and inflammatory cytokines TNF-α, IL-6 and IL-1β in RAW264.7 macrophages, showing good anti-inflammatory activity.

Abstract In this letter, a novel digital pre‐distortion (DPD) scheme for an end‐to‐end forward link (FL) channel in a satellite internet network (SIN) is first proposed. It aims at the unprecedented challenge of the model of non‐stationary (NS) cascade response consisting of channel fading and non‐linear behaviour of onboard payload. Unlike most existing schemes, the proposed DPD scheme explores a new model to describe the distortion with improved band‐limited memory polynomial (BLMP) by the equivalent response. To decrease the complexity of utilization, the authors design a new strategy to divide the unified non‐stationary situation into several different stationary situations. Meanwhile, a space‐time‐frequency stationary window function (STF‐WF) is proposed to compensate for the signal distortion. The experimental results demonstrate that the proposed schemes realize maximum total degradation (TD) gain by 15%.

The functionalized graphene, with prominent capability over expansion of interlayer spacing and enhancement of sodium ion diffusivity, has gained paramount interests in fabricating anode of sodium ion batteries(SIBs). Here, a poly(sodium 4-vinylbenzenesulfonate)graphene composite(PSS-rGO) was synthesized via an in situ insertion process. The insertion structure is based on the π-π interaction between the electron of graphene and the electron of PSS, which expands the interlayer spacing of rGO and, more importantly, stabilizes the structure of the composites, restrains the stack of graphene. Beyond that, the introduced sodium sulfonate groups are capable of increasing the diffusion rate of sodium ions for fast sodium ion adsorption, ensuring superior cycling performance. The performances of the simples were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD), Raman spectrometer(Raman), X-ray photoelectron spectrometer(XPS), electrochemical workstation and battery detection system. The results show the PSS-rGO remains a reversible capacity of 256 mAh·g-1 at 5 A·g-1 after 6000 cycles, with an ultralow decay rate of 0.003%. This work provides a feasible avenue for exploring advanced organic-inorganic hybrid materials with high capacity, fast sodium storage and ultralong lifespan for SIBs.

Yarn linear density and linear density unevenness between fragments involve the mass and mass variation of yarn per unit length, which are important indices to reflect the uniformity of yarn thickness. Aiming at the shortcomings of the traditional testing method, which uses a yarn length tester to test these indices by counting length first and then cutting and measuring weight, a testing device that measures weight and counts length synchronously is designed and developed, so that the yarn can be continuous, recyclable, and reusable. Length counting is conducted by a length-counting disk connected to a photoelectric coded disk, and the result of length counting can be accurate to 0.01 m. The original skein frame with a perimeter of 1 m is replaced, so that the error caused by yarn overlapping is avoided. Through program control, the testing of a plurality of groups of linear density values can be completed at one time to calculate the linear density unevenness of different fragments of yarn, and the yarn can be led to a recovery spool through a yarn guide cylinder to form a new package. Polyester/viscose 65/35 blended yarn was taken as a test sample and subjected to statistical analysis using SPSS software. It is found that the results of the newly developed device are closer to the arbitration value; the whole experiment is completed at one time, which avoids the secondary error and reduces the labor intensity; and the raw materials can be recycled, which saves labor and raw material costs. The device has high value for industrialization and popularization.

The thermodynamic behavior of 3-D orthogonal woven composite is studied to explore its structural heat transfer mechanism in a non-uniform heat load field based on finite element analysis (FEA). The temperature distribution characteristics of the resin matrix and the fabric reinforcement are observed to compare the heat absorption. Furthermore, the dynamic expansion and distribution characteristics of temperature in the 3-D orthogonal woven composite structure have also been quantitatively studied, together with simultaneously obtaining the path characteristics of the heat transfer in each system (i.e., warp yarns, weft yarns, and Z-yarns). In addition, the spatial temperature distribution characteristics of each yarn system in the fabric reinforcement are also explored. Thus, the structural mechanism of heat conduction for 3-D orthogonal woven composite is obtained.

doi：10.3969/j.issn.1672⁃6731.2021.12.015

With the development of network virtualization technology,the deployment of service function chain in multi-domain network brings new challenges to the optimization of service function chain.The traditional deployment method usually optimizes a single target,which is not suitable for multi-objective optimization,and cannot measure and balance the weight among optimization targets.Therefore,in order to optimize the delay,network load balancing and acceptance rate of large-scale service function chain deployment requests synchronously,a data normalization processing scheme is proposed,and a two-step SFC deployment algorithm based on reinforcement learning is designed.The algorithm takes transmission delay and load balancing as feedback parameters and balances the weight relationship between them,and the SFC acceptance rate is optimized by using reinforcement learning framework simultaneously.The experimental results show that,the delay of the algorithm is reduced by 71.8% compared with LASP method,the acceptance rate is increased by 4.6% compared with MDSP method,and the average load balancing is increased by 39.1% compared with GREEDY method under the large-scale requests.The multi-objective optimization effect is guaranteed.

Abstract Background White lupin (Lupinus albus) is a leguminous crop with elite adaptive ability in phosphorus-deficient soil and used as a model plant for studying phosphorus (P) use. However, the genetic basis of its adaptation to low P (LP) remains unclear. ATPase binding cassette (ABC) transports G subfamily play a crucial role in the transportation of biological molecules across the membrane. To date, identification of this subfamily has been analyzed in some plants, but no systematic analysis of these transporters in phosphorus acquisition is available for white lupin. Results This study identified 66 ABCG gene family members in the white lupin genome using comprehensive approaches. Phylogenetic analysis of white lupin ABCG transporters revealed six subclades based on their counterparts in Arabidopsis, displaying distinct gene structure and motif distribution in each cluster. Influences of the whole genome duplication on the evolution of L.albABCGs were investigated in detail. Segmental duplications appear to be the major driving force for the expansion of ABCGs in white lupin. Analysis of the Ka/Ks ratios indicated that the paralogs of the L.albABCG subfamily members principally underwent purifying selection. However, it was found that L.albABCG29 was a result of both tandem and segmental duplications. Overexpression of L.albABCG29 in white lupin hairy root enhanced P accumulation in cluster root under LP and improved plant growth. Histochemical GUS staining indicated that L.albABCG29 expression increased under LP in white lupin roots. Further, overexpression of L.albABCG29 in rice significantly improved P use under combined soil drying and LP by improving root growth associated with increased rhizosheath formation. Conclusion Through systematic and comprehensive genome-wide bioinformatics analysis, including conserved domain, gene structures, chromosomal distribution, phylogenetic relationships, and gene duplication analysis, the L.albABCG subfamily was identified in white lupin, and L.albABCG29 characterized in detail. In summary, our results provide deep insight into the characterization of the L.albABCG subfamily and the role of L.albABCG29 in improving P use.

Cocoon is a kind of natural biopolymer material with reasonable structure and various functions. However, its structure and functions are often destroyed in practical application. In this study, we took common Bombyx Mori as the research object, and provided different cocooning sites for single or multiple silkworms to construct common stereoscopic cocoons (“normal cocoons” [NC]) and flat cocoons (“single-silkworm flat cocoons” [SFC] and “multi-silkworm flat cocoons” [MFC]), respectively, and compared the morphological structure and basic properties of these cocoons. The study found that the flat cocoons have similar multi-layered variable structure and characteristics compared to those of the common cocoons; also, morphological characteristics and physical and chemical properties of silk fiber from outer layer to inner layer, such as sericin content, fiber fineness, and change rule of basic mechanical properties, are completely consistent with those of the common cocoons. It can be considered that the flat cocoons are constructed by silkworms in the same “procedural” process as that of common cocoons. Due to the expansion of cocooning space, the mechanical properties of fibers are significantly improved. By controlling the size of the cocooning space or the quantity of silkworms cocooning simultaneously, and the time of spinning, a cocoon material with controllable thickness, weight per square meter, porosity, and number of cocoon layers can be obtained as a composite material for direct application.

Lithium metal has a low redox potential (-3.04 V vs standard hydrogen electrode) and high specific capacity (3860 mAh/g), making it an ideal anode material for lithium secondary batteries. The solid-state lithium battery assembled by metal lithium negative electrode/solid electrolyte/lithium-inserted positive electrode is expected to become the power source of related technology industries such as aerospace, robotics, high-end electronics and electric vehicles in the future. However, during the charging and discharging process, due to the uneven deposition and dissolution of lithium, a large number of dendrites are produced on the contact surface between lithium and the electrolyte, and they continue to grow along the direction of the electrolyte, eventually causing the internal short circuit and failure of the battery. The use of a solid electrolyte with a higher Young’s modulus can block the growth of lithium dendrites to a large extent, but still cannot meet the requirements of battery long-term cycling and safety. In addition, metal lithium is in solid-solid contact with the solid electrolyte surface, causing problems such as high electrical resistance across the interface and interfacial reaction between metal lithium and solid electrolyte, which severely hinders the development and use of solid lithium metal batteries. The strategies for inhibiting the growth of lithium dendrites and improving the compatibility of solid-solid interface in metal lithium batteries based on solid electrolytes in recent years were reviewed in this article, and prospects for future development on the interface engineering of Li metal and solid-state electrolytes were prospected.