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Chinese Journal of Aeronautics 2024年第2期37卷 360-370页

作者： Yu LU Baozeng yue Bailong HAO Bole ma feng LIU Yuanyuan CHANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

In the process of stage separation of recoverable liquid launch vehicles,because of the large amount of residual fuel in the storage tanks,the influence of liquid sloshing on separation safety must be considered.Considering calculation simplicity and operation practicability,the Moving Pulsating Ball Model(MPBM)of large amplitude liquid sloshing is introduced into the calculation of launch vehicle stage separation.Combining the dynamic equation of the model with the energy relationship during"breathing movement",the formula calculating the force of liquid on the rigid body is derived.Compared with the calculations of commercial CFD calculation software,the accuracy of MPBM model is verified.Then,all the external forces and moments are applied to the rigid body of the stages,so that the translational and rotational dynamic equations of the stages are obtained respectively.According to the relative position of the two stages,the geometric shape of the interstage section and the engine of the second stage,the minimum clearance in the separation process can be decided to guarantee that the separation process is safe.

关键词： Moving Pulsating Ball Model(MPBM) Dynamics of stage separation Large amplitude sloshing Recoverable liquid launch vehicle Flight dynamics

Immune checkpoint inhibition mediated with liposomal nanomedicine for cancer therapy

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Military Medical Research 2024年第1期11卷 98-114页

作者： Guang-Long ma Wei-feng Lin Faculty of Medicine Centre for Cancer ImmunologyUniversity of SouthamptonSouthampton SO166YDUK Department of Molecular Chemistry and materials Science Weizmann Institute of Science76100 RehovotIsrael Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191China

Immune checkpoint blockade(ICB)therapy for cancer has achieved great success both in clinical results and on the market.At the same time,success drives more attention from scientists to improve it.However,only a small portion of patients are responsive to this therapy,and it comes with a unique spectrum of side effects termed immunerelated adverse events(irAEs).The use of nanotechnology could improve ICBs’delivery to the tumor,assist them in penetrating deeper into tumor tissues and alleviate their irAEs.Liposomal nanomedicine has been investigated and used for decades,and is well-recognized as the most successful nano-drug delivery system.The successful combination of ICB with liposomal nanomedicine could help improve the efficacy of ICB therapy.In this review,we highlighted recent studies using liposomal nanomedicine(including new emerging exosomes and their inspired nanovesicles)in associating ICB therapy.

关键词： Liposome Exosome Immune checkpoint blockade(ICB)

What Should We Focus on in Sepsis Fluid Resuscitation?--A Research Based on Scientometrics and Visual Analysis

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Biomedical and Environmental Sciences 2022年第2期35卷 155-160页

作者： HE Xiao Jun ZHU Xiang ma yue feng LIANG Jun Department of Emergency Medicine Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang China Department of Geriatrics The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001AnhuiChina IT Center Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009ZhejiangChina

Sepsis is a life-threatening condition and a global disease burden.Heterogeneous syndrome is defined as severe organ dysfunction caused by a dysregulated host response to infection,with renewed emphasis on the immune pathophysiology.Researchers worldwide constantly update the diagnostic criteria of sepsis and have introduced concepts such as“sepsis-3”“Surviving Sepsis Campaign(SSC)”“Early Goal-Directed Therapy(EGDT)”,the 3-h and 6-h bundles to an hour-1 bundle[1],“limited ventilation”“the best PEEP[2]”,and“Lung Protective-Ventilation”.Despite all efforts of experimental and clinical research during the last three decades,the ability to positively influence the course and outcome of the syndrome remains limited.

关键词： Sepsis PEEP Focus

Research on Pulsar Time Steered Atomic Time Algorithm Based on DPLL

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Research in Astronomy and Astrophysics 2024年第3期24卷 237-248页

作者： Ze-Hao Zheng Yang Liu Dan Shen Fan feng Jiu-Long Liu yue-Xin ma Xiang-Wei Zhu School of Electronic and Communication Engineering Sun Yat-sen UniversityShenzhen 518107China School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China School of Systems Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China

In today’s society,there is a wide demand for high-precision and high-stability time service in the fields of electric power,communication,transportation and finance.At present,the time standard in various countries is mainly based on atomic clocks,but the frequency drift of atomic clocks will affect the long-term stability performance.Compared with atomic clocks,millisecond pulsars have better long-term stability and can complement with the excellent short-term stability of atomic clocks.In order to improve the long-term stability of the atomic timescale,and then improve the timing accuracy,this paper proposes an algorithm for steering the atomic clock ensemble(ACE)by ensemble pulsar time(EPT)based on digital phase locked loop(DPLL).First,the ACE and EPT are generated by the ALGOS algorithm,then the ACE is steered by EPT based on DPLL to calibrate the long-term frequency drift of the atomic clock,so that the generated steered atomic time follows both the short-term stability characteristics of ACE and the long-term stability characteristics of EPT,and finally,the steered atomic time is used to calibrate the local cesium clock.The experimental results show that the long-term stability of atomic time after steering is improved by 2 orders of magnitude compared with that before steering,and the daily drift of a local cesium clock after calibration is less than 9.47 ns in 3 yr,3 orders of magnitude higher than that before calibration on accuracy.

关键词： (stars) pulsars general-time-methods data analysis-instabilities

CToMP: a cycle-task-oriented memory protection scheme for unmanned systems

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Science China(Information Sciences) 2024年第6期67卷 399-417页

作者： Chengyan ma Ning XI Di LU Yebo feng Jianfeng ma School of Cyber Engineering Xidian University School of Computer Science and Technology Xidian University Department of Computer and Information Science University of Oregon

Memory corruption attacks(MCAs) refer to malicious behaviors of system intruders that modify the contents of a memory location to disrupt the normal operation of computing systems, causing leakage of sensitive data or perturbations to ongoing processes. Unlike general-purpose systems, unmanned systems cannot deploy complete security protection schemes, due to their limitations in size, cost and performance.MCAs in unmanned systems are particularly difficult to defend against. Furthermore, MCAs have diverse and unpredictable attack interfaces in unmanned systems, severely impacting digital and physical sectors. In this paper, we first generalize, model and taxonomize MCAs found in unmanned systems currently, laying the foundation for designing a portable and general defense approach. According to different attack mechanisms,we found that MCAs are mainly categorized into two types — return2libc and return2shellcode. To tackle return2libc attacks, we model the erratic operation of unmanned systems with cycles and then propose a cycle-task-oriented memory protection(CToMP) approach to protect control flows from tampering. To defend against return2shellcode attacks, we introduce a secure process stack with a randomized memory address by leveraging the memory pool to prevent Shellcode from being executed. Moreover, we discuss the mechanism by which CTo MP resists the return-oriented programming(ROP) attack, a novel variant of return2libc attacks. Finally, we implement CTo MP on CUAV V5+ with Ardupilot and Crazyflie. The evaluation and security analysis results demonstrate that the proposed approach CTo MP is resilient to various MCAs in unmanned systems with low footprints and system overhead.

关键词： unmanned system memory corruption attack memory protection system security randomized memory address

Data driven analysis reveals prognostic genes and immunological targets in human sepsis-associated acute kidney injury

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World Journal of Emergency Medicine 2024年第2期15卷 91-97页

作者： Qing Zhao Jinfu ma Jianguo Xiao Zhe feng Hui Liu Department of Diagnosis and Treatment of Cadres the First Medical CenterChinese PLA General HospitalBeijing 100853China Intensive Care Unit the 305th Hospital of Chinese PLABeijing 100032China Department of Critical Care Medicine the First Medical CenterChinese PLA General HospitalBeijing 100853China Nephrology Department the First Medical CenterChinese PLA General HospitalBeijing 100853China

BACKGROUND:The molecular mechanism of sepsis-associated acute kidney injury(SA-AKI)is unclear.We analyzed co-differentially expressed genes(co-DEGs)to elucidate the underlying mechanism and intervention targets of SA-AKI.METHODS:The microarray datasets GSE65682,GSE30718,and GSE174220 were downloaded from the Gene Expression Omnibus(GEO)database.We identified the co-DEGs and constructed a gene co-expression network to screen the hub genes.We analyzed immune correlations and disease correlations and performed functional annotation of the hub genes.We also performed single-cell and microenvironment analyses and investigated the enrichment pathways and the main transcription factors.Finally,we conducted a correlation analysis to evaluate the role of the hub genes.RESULTS:Interleukin 32(IL32)was identified as the hub gene in SA-AKI,and the main enriched signaling pathways were associated with hemopoiesis,cellular response to cytokine stimulus,inflammatory response,and regulation of kidney development.Additionally,IL32 was significantly associated with mortality in SA-AKI patients.Monocytes,macrophages,T cells,and NK cells were closely related to IL32 and were involved in the immune microenvironment in SA-AKI patients.IL32 expression increased significantly in the kidney of septic mouse.Toll-like receptor 2(TLR2)was significantly and negatively correlated with IL32.CONCLUSION:IL32 is the key gene involved in SA-AKI and is significantly associated with prognosis.TLR2 and relevant immune cells are closely related to key genes.

关键词： Sepsis Acute kidney injury Interleukin 32 Toll-like receptor 2 Bioinformatics analysis

Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： feng Peng Yanming ma Chris J.Pickard Hanyu Liu maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard materials & Key Laboratory of material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of materials Science & Metallurgy University of Cambridge Advanced Institute for materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior

Reducing Subspaces of Toeplitz Operators Induced by a Class of Non-analytic Monomials over the Unit Ball

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Acta mathematica Sinica,English Series 2024年第7期40卷 1767-1777页

作者： Yan yue SHI Bo ZHANG Xu TANG Yu feng LU School of mathematical Sciences Ocean University of China School of mathematics and Information Sciences Yantai University School of mathematical Sciences Space Engineering University School of mathematical Sciences Dalian University of Technology

In this paper, we describe the minimal reducing subspaces of Toeplitz operators induced by non-analytic monomials on the weighted Bergman spaces and Dirichlet spaces over the unit ball B2. It is proved that each minimal reducing subspace M is finite dimensional, and if dim M ≥ 3,then M is induced by a monomial. Furthermore, the structure of commutant algebra ■ is determined by N and the two dimensional minimal reducing subspaces of ■. We also give some interesting examples.

关键词： Reducing subspace operator-weighted shifts Toeplitz operator von Neumann algebra 47B35 47B37

Unraveling the complexity of polycystic ovary syndrome with animal models

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Journal of Genetics and Genomics 2024年第2期51卷 144-158页

作者： Huanju Liu Mixue Tu Zhiyong Yin Dan Zhang Jun ma feng He Center for Genetic Medicine The Fourth Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310058China Key Laboratory of Women's Reproductive Health of Zhejiang Province and Department of Reproductive Endocrinology Women's HospitalZhejiang University School of MedicineHangzhouZhejiang 310006China Zhejiang Provincial Clinical Research Center for Child Health Women's HospitalZhejiang University School of MedicineHangzhouZhejiang 310006China Clinical Research Center on Birth Defect Prevention and Intervention of Zhejiang Province HangzhouZhejiang 310006China Institute of Genetics Zhejiang University International School of MedicineHangzhouZhejiang 310058China Zhejiang Provincial Key Laboratory of Genetic and Developmental Disorder HangzhouZhejiang 310058China

Polycystic ovary syndrome (PCOS) is a highly familial and heritable endocrine disorder. Over half of the daughters born to women with PCOS may eventually develop their own PCOS-related symptoms. Progress in the treatment of PCOS is currently hindered by the complexity of its clinical manifestations and incomplete knowledge of its etiopathogenesis. Various animal models, including experimentally induced, naturally occurring, and spontaneously arising ones, have been established to emulate a wide range of phenotypical and pathological traits of human PCOS. These studies have led to a paradigm shift in understanding the genetic, developmental, and evolutionary origins of this disorder. Furthermore, emerging evidence suggests that animal models are useful in evaluating state-of-the-art drugs and treatments for PCOS. This review aims to provide a comprehensive summary of recent studies of PCOS in animal models, highlighting the power of these disease models in understanding the biology of PCOS and aiding high-throughput approaches.

关键词： Polycystic ovary syndrome Animal model Genetc manipulation Developmnental progtanning Drug screening

Knockout of a rice K5.2 gene increases Ca accumulation in the grain

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Journal of Integrative Plant Biology 2024年第2期66卷 252-264页

作者： Peitong Wang Naoki Yamaji Namiki Mitani-Ueno Jun Ge Jian feng ma National Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China Institute of Plant Science and Resources Okayama UniversityKurashiki 710-0046Japan

Rice is a staple food for half of the world’s population,but it is a poor dietary source of calcium(Ca)due to the low concentration.It is an important issue to boost Ca concentration in this grain to improve Ca deficiency risk,but the mechanisms underlying Ca accumulation are poorly understood.Here,we obtained a rice(Oryza sativa)mutant with high shoot Ca accumulation.The mutant exhibited 26%-53% higher Ca in shoots than did wild-type rice(WT)at different Ca supplies.Ca concentration in the xylem sap was 36% higher in the mutant than in the WT.There was no difference in agronomic traits between the WT and mutant,but the mutant showed 25% higher Ca in the polished grain compared with the WT.map-based cloning combined with a complementation test revealed that the mutant phenotype was caused by an 18-bp deletion of a gene,OsK5.2,belonging to the Shaker-like K+channel family.OsK5.2 was highly expressed in the mature region of the roots and its expression in the roots was not affected by Ca levels,but upregulated by low K.Immunostaining showed that OsK5.2 was mainly expressed in the pericycle of the roots.Taken together,our results revealed a novel role for OsK5.2 in Ca translocation in rice,and will be a good target for Ca biofortification in rice.

关键词： accumulation biofortification calcium OsK5.2 pericycle rice translocation