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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu Xiang Yang jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast loading.First,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage test.Second,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation method.Finally,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact block.The calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the model.The residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged panel.The results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

A novel small-signal equivalent circuit model for GaN HEMTs incorporating a dual-field-plate

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Journal of Semiconductors 2024年第5期45卷 61-68页

作者： Jinye Wang jun liu Zhenxin Zhao School of Integrated Circuit Science and Engineering Hangzhou Dianzi UniversityHangzhou 310018China

An accurate and novel small-signal equivalent circuit model for GaN high-electron-mobility transistors(HEMTs)is proposed,which considers a dual-field-plate(FP)made up of a gate-FP and a source-FP.The equivalent circuit of the overall model is composed of parasitic elements,intrinsic transistors,gate-FP,and source-FP networks.The equivalent circuit of the gate-FP is identical to that of the intrinsic transistor.In order to simplify the complexity of the model,a series combination of a resistor and a capacitor is employed to represent the source-FP.The analytical extraction procedure of the model parameters is presented based on the proposed equivalent circuit.The verification is carried out on a 4×250μm GaN HEMT device with a gate-FP and a source-FP in a 0.45μm technology.Compared with the classic model,the proposed novel small-signal model shows closer agreement with measured S-parameters in the range of 1.0 to 18.0 GHz.

关键词： small-signal model dual field-plate(FP) GaN high-electron-mobility transistors(HEMT) parameter extraction

Clinical efficacy of the topical application of tranexamic acid in tendon release in the hand:A randomized controlled trial

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Chinese Journal of Traumatology 2024年第3期27卷 163-167页

作者： Hao liu jun liu Yong-Wei Wu Ming Zhou Yong-jun Rui Suzhou Medical College of Soochow University Suzhou215000Jiangsu provinceChina Department of Traumatic Oorthopedics Wuxi Ninth People's Hospital Ailiated to Soochow UniversityWuxi214000Jiangsu provinceChina

Purpose:To study the clinical effectiveness of the topical application of tranexamic acid in hand tendon release.Methods:This was a randomized controlled trial conducted after receiving approval from the local ethics committee according to guidelines from the Helsinki Declaration.Eighty patients who underwent hand tendon release operation in our hospital from January 2021 to December 2022 were included and randomly divided into 2 groups.Patients in the tranexamic acid group(40 cases)received intraoperative topical application of 2 g of tranexamic acid after tendon release,while patients in the conventional group(40 cases)did not receive topical application of tranexamic acid during operation.The operation time,perioperative hemoglobin changes,total blood loss,incidence of early postoperative complications,and total active movement(TAM)before surgery and 6 months after surgery were compared between the 2 groups.The continuous variable which follows normal distribution expressed by mean±SD and used t-test to compare between groups.Meanwhile,categorical variables were used by Chi-square test,and a p<0.05 indicated that the differences were statistically significant.Results:Both groups were followed up for 7-18 months,with a mean of 10.3 months.Postoperative decrease in hemoglobin was significantly less in the tranexamic acid group than in the conventional group(t=7.611,p<0.001).The total blood loss in the tranexamic acid group(74.33±20.50)mL was less than that in the conventional group(83.05±17.73)mL,and the difference was statistically significant(p<0.05).Both groups showed improvement in thumb/finger flexion and extension range of motion after surgery,and the TAM improved compared with those before surgery,and the difference was statistically significant(p<0.001).The TAM improved more significantly in the tranexamic acid group(87.68°±10.44°)than in the conventional group(80.47°±10.93°)at 6 months after surgery,with a statistically significant difference(t=3.013,p<0.001).There was no significant difference in opera

关键词： Tranexamic acid Tendon release Total active movement Tendon adhesion

A Task Scheduling Algorithm Based on Clustering Pre-processing in Space-Based Information Network

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Chinese Journal of Electronics 2024年第1期33卷 217-230页

作者： Yufei WANG jun liu Shengnan ZHANG Sai XU Jingyi WANG School of Computer Science and Engineering Northeastern University

With the diversification of space-based information network task requirements and the dramatic increase in demand, the efficient scheduling of various tasks in space-based information network becomes a new challenge. To address the problems of a limited number of resources and resource heterogeneity in the space-based information network, we propose a bilateral pre-processing model for tasks and resources in the scheduling pre-processing stage. We use an improved fuzzy clustering method to cluster tasks and resources and design coding rules and matching methods to match similar categories to improve the clustering effect. We propose a space-based information network task scheduling strategy based on an ant colony simulated annealing algorithm for the problems of high latency of space-based information network communication and high resource dynamics. The strategy can efficiently complete the task and resource matching and improve the task scheduling performance. The experimental results show that our proposed task scheduling strategy has less task execution time and higher resource utilization than other algorithms under the same experimental conditions. It has significantly improved scheduling performance.

关键词： Space-based information network Task scheduling Resource clustering Ant colony optimization Simulated annealing

The essential roles of m^(6)A modification in osteogenesis and common bone diseases

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Genes & Diseases 2024年第1期11卷 335-345页

作者： Yuxi Gu Yidan Song Yihua Pan jun liu State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases Department of OrthodonticsWest China Hospital of StomatologySichuan UniversityChengduSichuan 610041China

N6-methyladenosine(m^(6)A)is the most prevalent modification in the eukaryotic transcriptome and has a wide range of functions in coding and noncoding RNAs.It affects the fate of the modified RNA,including its stability,splicing,and translation,and plays an important role in post-transcriptional regulation.Bones play a key role in supporting and pro-tecting muscles and other organs,facilitating the movement of the organism,ensuring blood production,etc.Bone diseases such as osteoarthritis,osteoporosis,and bone tumors are serious public health problems.The processes of bone development and osteogenic differen-tiation require the precise regulation of gene expression through epigenetic mechanisms including histone,DNA,and RNA modifications.As a reversible dynamic epigenetic mark,m^(6)A modifications affect nearly every important biological process,cellular component,and molecular function,including skeletal development and homeostasis.In recent years,studies have shown that m^(6)A modification is involved in osteogenesis and bone-related diseases.In this review,we summarized the proteins involved in RNA m^(6)A modification and the latest progress in elucidating the regulatory role of m^(6)A modification in bone formation and stem cell direc-tional differentiation.We also discussed the pathological roles and potential molecular mech-anisms of m^(6)A modification in bone-related diseases like osteoporosis and osteosarcoma and suggested potential areas for new strategies that could be used to prevent or treat bone de-fects and bone diseases.

关键词： Bone diseases m^(6)A modification Osteogenesis Regulatory role Stem cells

The Roadmap of 2D Materials and Devices Toward Chips

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Nano-Micro Letters 2024年第6期16卷 343-438页

作者： Anhan liu Xiaowei Zhang Ziyu liu Yuning Li Xueyang Peng Xin Li Yue Qin Chen Hu Yanqing Qiu Han Jiang Yang Wang Yifan Li jun Tang jun liu Hao Guo Tao Deng Songang Peng He Tian Tian‑Ling Ren School of Integrated Circuits and Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100049People’s Republic of China School of Microelectronics Fudan UniversityShanghai 200433People’s Republic of China State Key Laboratory of Dynamic Measurement Technology Shanxi Province Key Laboratory of Quantum Sensing and Precision MeasurementNorth University of ChinaTaiyuan 030051People’s Republic of China High‑Frequency High‑Voltage Device and Integrated Circuits R&D Center Institute of MicroelectronicsChinese Academy of SciencesBeijing 100029People’s Republic of China School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China School of Integrated Circuits University of Chinese Academy of SciencesBeijing 100049People’s Republic of China IMECAS-HKUST-Joint Laboratory of Microelectronics Beijing 100029People’s Republic of China

Due to the constraints imposed by physical effects and performance degra certain limitations in sustaining the advancement of Moore’s law.Two-dimensional(2D)materials have emerged as highly promising candidates for the post-Moore era,offering significant potential in domains such as integrated circuits and next-generation computing.Here,in this review,the progress of 2D semiconductors in process engineering and various electronic applications are summarized.A careful introduction of material synthesis,transistor engineering focused on device configuration,dielectric engineering,contact engineering,and material integration are given first.Then 2D transistors for certain electronic applications including digital and analog circuits,heterogeneous integration chips,and sensing circuits are discussed.Moreover,several promising applications(artificial intelligence chips and quantum chips)based on specific mechanism devices are introduced.Finally,the challenges for 2D materials encountered in achieving circuit-level or system-level applications are analyzed,and potential development pathways or roadmaps are further speculated and outlooked.

关键词： Two-dimensional materials Roadmap Integrated circuits Post-Moore era

Multisensory Conflict Impairs Cortico-Muscular Network Connectivity and Postural Stability: Insights from Partial Directed Coherence Analysis

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Neuroscience Bulletin 2024年第1期40卷 79-89页

作者： Guozheng Wang Yi Yang Kangli Dong Anke Hua Jian Wang jun liu Key Laboratory for Biomedical Engineering of Ministry of Education College of Biomedical Engineering&Instrument ScienceZhejiang UniversityHangzhou 310058China Taizhou Key Laboratory of Medical Devices and Advanced Materials Research Institute of Zhejiang University-TaizhouTaizhou 318000China Department of Sports Science College of EducationZhejiang UniversityHangzhou 310058China Center for Psychological Science Zhejiang UniversityHangzhou 310058China

Sensory conflict impacts postural control,yet its effect on cortico-muscular interaction remains underexplored.We aimed to investigate sensory conflict's influence on the cortico-muscular network and postural stability.We used a rotating platform and virtual reality to present subjects with congruent and incongruent sensory input,recorded EEG(electroencephalogram)and EMG(electromyogram)data,and constructed a directed connectivity network.The results suggest that,compared to sensory congruence,during sensory conflict:(1)connectivity among the sensorimotor,visual,and posterior parietal cortex generally decreases,(2)cortical control over the muscles is weakened,(3)feedback from muscles to the cortex is strengthened,and(4)the range of body sway increases and its complexity decreases.These results underline the intricate effects of sensory conflict on cortico-muscular networks.During the sensory conflict,the brain adaptively decreases the integration of conflicting information.Without this integrated information,cortical control over muscles may be lessened,whereas the muscle feedback may be enhanced in compensation.

关键词： Cortico-muscular interaction Postural control Virtual reality Electroencephalogram Electromyography Sensory integration

Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence Technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao Jian Zheng Jin Guo Yunbo Shi Hengzhen Feng jun Tang jun liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped lattices.The effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and analyzed.The target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent lattices.The proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k Hz.After the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target frequency.These results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

Magnetic nanoparticle-modified hollow double-shell SiC@C@FeCo with excellent electromagnetic wave absorption

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Nano Research 2024年第4期17卷 3164-3174页

作者： Guiyu Peng Jintang Zhou Jiaqi Tao Weize Wang jun liu junru Yao Yijie liu Zhengjun Yao College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211100China Key Laboratory of Material Preparation and Protection for Harsh Environment(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information TechnologyNanjing 211100China

Integrated micro and nanostructures,heterogeneous components,defects,and interfaces is the way to develop high-performance microwave absorbing materials.However,there still needs to be more precise experimental routes and effective validation.In this work,by a continuous process of vacuum sintering,hydrothermal,and carbon thermal reduction,magnetic FeCo nanoparticles were successfully embedded on the hollow double-shell mesoporous SiC@C surface,thus solving the challenges of a single component loss mechanism.The hollow double-shell nanostructure introduces air to enhance impedance matching while significantly reducing the density of the material.The extensive defects and heterogeneous grain boundaries effectively enhance the polarization loss capacity.The magnetic loss mechanism introduced by the magnetic particles effectively improves the impedance matching properties of the material.The synergy of these multiple advantages has enabled the SCFC_(2)-8(here SiC@C@FeCo is abbreviated to SCFC,2 represents the initial metal ion content,and 8 represents the hydrothermal time)sample to achieve an adequate absorption bandwidth of 6.09 GHz at 2.0 mm.With a minimum reflection loss of-60.56 dB,the absorption bandwidth can cover the entire C,X,and Ku bands by adjusting the matching thickness(1.3–4.0 mm).This work provides a valuable paradigm for the deeper exploitation of microwave absorption potential and guides the development of other high-performance materials.

关键词： SiC@C@FeCo(SCFC)composites core–shell hollow structure microwave absorption

Outcomes of endoscopic sclerotherapy for jejunal varices at the site of choledochojejunostomy (with video): Three case reports

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World Journal of Gastroenterology 2024年第14期30卷 2059-2067页

作者： jun liu Peng Wang Li-Mei Wang Jing Guo Ning Zhong Department of Gastroenterology Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina

BACKGROUND Hemorrhage associated with varices at the site of choledochojejunostomy is an unusual,difficult to treat,and often fatal manifestation of portal hypertension.So far,no treatment guidelines have been established.CASE SUMMARY We reported three patients with jejunal varices at the site of choledochojejun-ostomy managed by endoscopic sclerotherapy with lauromacrogol/α-butyl cyanoacrylate injection at our institution between june 2021 and August 2023.We reviewed all patient records,clinical presentation,endoscopic findings and treatment,outcomes and follow-up.Three patients who underwent pancre-aticoduodenectomy with a Whipple anastomosis were examined using conven-tional upper gastrointestinal endoscopy for suspected hemorrhage from the afferent jejunal loop.Varices with stigmata of recent hemorrhage or active he-morrhage were observed around the choledochojejunostomy site in all three patients.Endoscopic injection of lauromacrogol/α-butyl cyanoacrylate was carried out at jejunal varices for all three patients.The bleeding ceased and patency was observed for 26 and 2 months in two patients.In one patient with multiorgan failure and internal environment disturbance,rebleeding occurred 1 month after endoscopic sclerotherapy,and despite a second endoscopic sclero-therapy,repeated episodes of bleeding and multiorgan failure resulted in eventual death.CONCLUSION We conclude that endoscopic sclerotherapy with lauromacrogol/α-butyl cyanoac-rylate injection can be an easy,effective,safe and low-cost treatment option for jejunal varicose bleeding at the site of choledochojejunostomy.

关键词： Endoscopic sclerotherapy Jejunal varices Choledochojejunostomy Portal vein hypertension Case report