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A muon high-resolution pseudorange measurement method: Application to muon navigation in confined spaces

Chinese Journal of Aeronautics 2024年第4期37卷 391-404页

作者： Haoyang li Chunxi ZHANG Xingming FAN Longjie TIAN tianqi li Yang PANG Yanqiang YANG Institute of Optics and Electronics School of Instrumentation Science and Optoelectronics EngineeringBeihang UniversityBeijing 100191China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Confined spaces such as polar regions, deep earth and deep ocean are crucial navigation scenarios where traditional navigation techniques have difficulty in obtaining external signals for positioning. The cosmic ray muons, which carry the spatial and energetic information, are easy to penetrate these confined spaces. Therefore, the unique muon characteristic provides a new perspective to estimate detector position, which can be considered using in confined spaces navigation.In this paper, a well-developed theory of muon navigation is established by combining a muon pseudorange measurement method. Moreover, an Equivalent Velocity Calculation Model(EVCM)and a Muon Sequence Matching Technology(MSMT) are proposed. The first model corrects flight pseudorange error caused by the relativistic energy loss and the second technology compensates the random error in pseudorange measurement. Further, a series of simulations are performed to analyze the muon events number which can be received by detector in different scenarios with the variations of zenith angle, detector area, varied detector plates gap, and muon flight distance.Meanwhile, the simulation results demonstrate that the muon navigation update rate every 10 minutes can reach 5.989 in confined spaces at 100 m, and further pseudorange error analysis indicates that the meter-level positioning accuracy can be acquired. Finally, we construct a muon coincidence measurement scheme and verify that the laws of the muon positioning system for high-energy muons are consistent with the simulation results.

关键词： Muon navigation Cosmic ray muons Muon detection technology Muon transmission technology Pseudorange measurement

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Transplantation of fibrin-thrombin encapsulated human induced neural stem cells promotes functional recovery of spinal cord injury rats through modulation of the microenvironment

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Neural Regeneration Research 2024年第2期19卷 440-446页

作者： Sumei liu Baoguo liu Qian li tianqi Zheng Bochao liu Mo li Zhiguo Chen Cell Therapy Center Beijing Institute of GeriatricsXuanwu HospitalCapital Medical UniversityNational Clinical Research Center for Geriatric Diseasesand Key Laboratory of Neurodegenerative DiseasesMinistry of EducationBeijingChina Center of Neural Injury and Repair Beijing Institute for Brain DisordersBeijingChina Center of Parkinson’s Disease Beijing Institute for Brain DisordersBeijingChina

Recent studies have mostly focused on engraftment of cells at the lesioned spinal cord,with the expectation that differentiated neurons facilitate recovery.Only a few studies have attempted to use transplanted cells and/or biomaterials as major modulators of the spinal cord injury microenvironment.Here,we aimed to investigate the role of microenvironment modulation by cell graft on functional recovery after spinal cord injury.Induced neural stem cells reprogrammed from human peripheral blood mononuclear cells,and/or thrombin plus fibrinogen,were transplanted into the lesion site of an immunosuppressed rat spinal cord injury model.Basso,Beattie and Bresnahan score,electrophysiological function,and immunofluorescence/histological analyses showed that transplantation facilitates motor and electrophysiological function,reduces lesion volume,and promotes axonal neurofilament expression at the lesion core.Examination of the graft and niche components revealed that although the graft only survived for a relatively short period(up to 15 days),it still had a crucial impact on the microenvironment.Altogether,induced neural stem cells and human fibrin reduced the number of infiltrated immune cells,biased microglia towards a regenerative M2 phenotype,and changed the cytokine expression profile at the lesion site.Graft-induced changes of the microenvironment during the acute and subacute stages might have disrupted the inflammatory cascade chain reactions,which may have exerted a long-term impact on the functional recovery of spinal cord injury rats.

关键词： biomaterial fibrinogen functional recovery induced neural stem cell transplantation microenvironment microglia spinal cord injury thrombin

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Maslinic acid supplementation prevents di(2-ethylhexyl)phthalate-induced apoptosis via PRDX6 in peritubular myoid cells of Chinese forest musk deer

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Journal of Environmental Sciences 2024年第9期143卷 47-59页

作者： Heran Cao Zhenpeng li tianqi Jin Shuyang He Shujuan liu Long li Yang Wang Ye Gong Gang Wang Fangxia Yang Wuzi Dong College of Animal Science and Technology Northwest A&F UniversityShaanxi 712100China College of Forestry Northwest A&F UniversityShaanxi 712100China Biology Research Centre of Qin-Mountains Wildlife Northwest A&F UniversityShaanxi 712100China Shaanxi Qiyuan-Times Agri-Tech Development Co.Ltd. Shaanxi 725000China

Chinese forest musk deer(FMD),an endangered species,have exhibited low reproductive rates even in captivity due to stress conditions.Investigation revealed the presence of di(2-ethylhexyl)phthalate(DEHP),an environmental endocrine disruptor,in the serum and skin of captive FMDs.Feeding FMDs with maslinic acid(MA)has been observed to alleviate the stress response and improve reproductive rates,although the precise molecular mechanisms remain unclear.Therefore,this study aims to investigate the molecular mechanisms underlying the alleviation of DEHP-induced oxidative stress and cell apoptosis in primary peritubular myoid cells(PMCs)through MA intake.Primary PMCs were isolated and exposed to DEHP in vitro.The results demonstrated that DEHP significantly suppressed antioxidant levels and promoted cell apoptosis in primary PMCs.Moreover,interfering with the expression of PRDX6 was found to induce excessive reactive oxygen species(ROS)production and cell apoptosis in primary PMCs.Supplementation with MA significantly upregulated the expression of PRDX6,thereby attenuating DEHP-induced oxidative stress and cell apoptosis in primary PMCs.These findings provide a theoretical foundation for mitigating stress levels and enhancing reproductive capacity of in captive FMDs.

关键词： Maslinic acid Forest musk deer Di(2-ethylhexyl)phthalate Peritubular myoid cells PRDX6

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Time-history performance optimization of flapping wing motion using a deep learning based prediction model

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Chinese Journal of Aeronautics 2024年第5期37卷 317-331页

作者： tianqi WANG liu liU Jun li lifang ZENG School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China Huanjiang Laboratory Zhuji 311800China

Flapping Wing Micro Aerial Vehicles(FWMAVs)have caused great concern in various fields because of their high efficiency and maneuverability.Flapping wing motion is a very important factor that affects the performance of the aircraft,and previous works have always focused on the time-averaged performance optimization.However,the time-history performance is equally important in the design of motion mechanism and flight control system.In this paper,a time-history performance optimization framework based on deep learning and multi-island genetic algorithm is presented,which is designed in order to obtain the optimal two-dimensional flapping wing motion.Firstly,the training dataset for deep learning neural network is constructed based on a validated computational fluid dynamics method.The aerodynamic surrogate model for flapping wing is obtained after the convergence of training.The surrogate model is tested and proved to be able to accurately and quickly predict the time-history curves of lift,thrust and moment.Secondly,the optimization framework is used to optimize the flapping wing motion in two specific cases,in which the optimized propulsive efficiencies have been improved by over 40%compared with the baselines.Thirdly,a dimensionless parameter C_(variation)is proposed to describe the variation of the time-history characteristics,and it is found that C_(variation)of lift varies significantly even under close time-averaged performances.Considering the importance of time-history performance in practical applications,the optimization that integrates the propulsion efficiency as well as C_(variation)is carried out.The final optimal flapping wing motion balances good time-averaged and time-history performance.

关键词： FWMAV Flapping wing motion Deep learning Unsteady aerodynamic performance Optimization Time-history curve

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Sampling-efficient path planning and improved actor-critic-based obstacle avoidance for autonomous robots

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Science China(Information Sciences) 2024年第5期67卷 197-214页

作者： Yefeng YANG Tao HUANG tianqi WANG Wenyu YANG Han CHEN Boyang li Chih-yung WEN Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic University Center for Control Theory and Guidance Technology Harbin Institute of Technology School of Engineering The University of Newcastle Research Center for Unmanned Autonomous Systems The Hong Kong Polytechnic University

Autonomous robots have garnered extensive utilization in diverse fields. Among the critical concerns for autonomous systems, path planning holds paramount importance. Notwithstanding considerable efforts in its development over the years, path planning for autonomous systems continues to grapple with challenges related to low planning efficiency and inadequate obstacle avoidance response in a timely manner.This study proposes a novel and systematic solution to the path planning problem within intricate office buildings. The solution consists of a global planner and a local planner. To handle the global planning aspect, an adaptive clustering-based dynamic programming rapidly exploring random tree(ACDP-RRT) algorithm is proposed. ACDP-RRT effectively identifies obstacles on the map by leveraging geometric features.These obstacles are then represented as a collection of sequentially arranged convex polygons, optimizing the sampling region and significantly enhancing sampling efficiency. For local planning, a network decoupling actor-critic(ND-AC) algorithm is employed. The proposed ND-AC simplifies the local planner design process by integrating planning and control loops into a neural network(NN) trained via an end-to-end model-free deep reinforcement learning(DRL) framework. Moreover, the adoption of network decoupling(ND) techniques leads to an improved obstacle avoidance success rate when compared to conventional actor-critic(AC)-based methods. Extensive simulations and experiments are conducted to demonstrate the effectiveness and robustness of the proposed approach.

关键词： rapidly exploring random tree (RRT) adaptive clustering network decoupling actor critic (AC) path planning

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Pyridinic-N doping carbon layers coupled with tensile strain of FeNi alloy for activating water and urea oxidation

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Green Energy & Environment 2024年第4期9卷 684-694页

作者： Guangfu Qian Wei Chen Jinli Chen li Yong Gan tianqi Yu Miaojing Pan Xiaoyan Zhuo Shibin Yin Guangxi Key Laboratory of Electrochemical Energy Materials College of Chemistry and Chemical EngineeringState Key Laboratory of Processing for Non-Ferrous Metal and Featured MaterialsGuangxi University100 Daxue RoadNanning530004China Institute for Structure and Function and Department of Physics Chongqing UniversityChongqing400030China

Exploitation of oxygen evolution reaction(OER)and urea oxidation reaction(UOR)catalysts with high activity and stability at large current density is a major challenge for energy-saving H_(2) production in water electrolysis.Herein,we use the pyridinic-N doping carbon layers coupled with tensile strain of FeNi alloy activated by NiFe_(2)O_(4)(FeNi/NiFe_(2)O_(4)@NC)for efficiently increasing the performance of water and urea oxidation.Due to the tensile strain effect on FeNi/NiFe_(2)O_(4)@NC,it provides a favorable modulation on the electronic properties of the active center,thus enabling amazing OER(η_(100)=196 mV)and UOR(E_(10)=1.32 V)intrinsic activity.Besides,the carbon-coated layers can be used as armor to prevent FeNi alloy from being corroded by the electrolyte for enhancing the OER/UOR stability at large current density,showing high industrial practicability.This work thus provides a simple way to prepare high-efficiency catalyst for activating water and urea oxidation.

关键词： Carbon-encapsulated Tensile strain Catalyst Oxygen evolution reaction Urea oxidation reaction

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Colony-stimulating factor-1 receptor inhibition combined with paclitaxel exerts effective antitumor effects in the treatment of ovarian cancer

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Genes & Diseases 2024年第3期11卷 400-416页

作者： Meijia Yu Yiming Wu Qingfang li Weiqi Hong Yang Yang Xiaoyi Hu Yanfei Yang tianqi Lu Xia Zhao Xiawei Wei Laboratory of Aging Research and Cancer Drug Target State Key Laboratory of Biotherapy and Cancer CenterNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengduSichuan 610041China Department of Gynecology and Obstetrics Development and Related Disease of Women and Children Key Laboratory of Sichuan ProvinceKey Laboratory of Birth Defects and Related Diseases of Women and ChildrenMinistry of EducationWest China Second HospitalSichuan UniversityChengduSichuan 610041China Department of Obstetrics and Gynecology The First Affiliated HospitalArmy Medical UniversityChongqing 400038China

Ovarian cancer is the tumor with the highest mortality among gynecological malig-nancies.Studies have confirmed that paclitaxel chemoresistance is associated with increased infiltration of tumor-associated macrophages(TAMs)in the microenvironment.Colony-stimu-lating factor 1(CSF-1)receptor(CSF-1R)plays a key role in regulating the number and differ-entiation of macrophages in certain solid tumors.There are few reports on the effects of targeted inhibition of CSF-1R in combination with chemotherapy on ovarian cancer and the tu-mor microenvironment.Here,we explored the antitumor efficacy and possible mechanisms of the CSF-1R inhibitor pexidartinib(PLX3397)when combined with the first-line chemothera-peutic agent paclitaxel in the treatment of ovarian cancer.We found that CSF-1R is highly ex-pressed in ovarian cancer cells and correlates with poor prognosis.Treatment by PLX3397 in combination with paclitaxel significantly inhibited the growth of ovarian cancer both in vitro and in vivo.Blockade of CSF-1R altered the macrophage phenotype and reprogrammed the immunosuppressive cell population in the tumor microenvironment.

关键词： CSF-1R Ovariancancer Paclitaxel PLX3397 Targeted therapy Tumor-associated macrophages

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Molecular behavior and interactions with microbes during anaerobic degradation of bio-derived DOM in waste leachate

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Journal of Environmental Sciences 2023年第4期126卷 174-183页

作者： Junjie Qiu tianqi li Fan Lü Yulong Huang Chao li Hua Zhang liming Shao Pinjing He Institute of Waste Treatment and Reclamation Tongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Shanghai Engineering Research Center of Multi-source Solid Wastes Co-Processing and Energy Utilization Shanghai 200092China

It is the key to control bio-derived dissolved organic matters (DOM) in order to reduce the effluent concentration of wastewater treatment, especially for waste leachate with high organic contaminants. In the present study, the anaerobic degradation of aerobically stabilized DOM was investigated with DOM substrate isolated through electrodialysis. The degradation of bio-derived DOM was confirmed by reduction of 15%of total organic carbon in 100 days.We characterized the molecular behavior of bio-derived DOM by coupling molecular and biological information analysis. Venn based Sankey diagram of mass features showed the transformation of bio-derived DOM mass features. Occurrence frequency analysis divided mass features into six categories so as to distinguish the fates of intermediate metabolites and persistent compounds. Reactivity continuum model and machine learning technologies realized the semi-quantitative determination on the kinetics of DOM mass features in the form of pseudo-first order, and confirmed the reduction of inert mass features. Furthermore, network analysis statistically establish relationship between DOM mass features and microbes to identify the active microbes that are able to utilize bio-derived DOM. This work confirmed the biological technology is still effective in controlling recalcitrant bio-derived DOM during wastewater treatment.

关键词： Soluble microbial products Data mining Machine learning Solid waste Orbitrap

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A novel cabazitaxel liposomes modified with ginsenoside Rk1 for cancer targeted therapy

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Acupuncture and Herbal Medicine 2024年第1期4卷 113-121页

作者： Dandan Huang Zhongjie Tang Xiao Pu tianqi Wang Feiyan Gao Chong li Medical Research Institute College of Pharmaceutical SciencesSouthwest UniversityChongqingChina Department of Pharmacy National University of SingaporeSingapore 117545Singapore

Objective:In this study,we aim to enhance the anti-prostate cancer efficacy of cabazitaxel(CTX)and reduce its immunosuppression and systemic toxicity by developing CTX-loaded liposomes modified with ginsenoside Rk1(Rk1/CTX-lip).Methods:Physical and chemical properties of Rk1/CTX-lip were investigated.We evaluated the biological functions of Rk1/CTXlip,both in vitro and in vivo.A subcutaneous prostate cancer(RM-1)-bearing mouse model was established to study the efficacy of Rk1/CTX-lip inhibition in tumors.Simultaneously,a Candida albicans infection model was established in tumor-bearing mice to study the infection-relieving efficacy of Rk1/CTX-lip.Finally,biocompatibility and in vivo safety of Rk1/CTX-lip were evaluated.Results:We successfully prepared Rk1/CTX-lip,achieving high CTX encapsulation efficiency(97.24±0.75)%and physical stability.Rk1/CTX-lip demonstrated evasion of macrophage phagocytosis,effective tumor tissue targeting,and a significant reduction(>50%)in average tumor volume compared with Chol/CTX-lip.Moreover,it relieved the concurrent infection burden and effectively regulated immune organs and cells,demonstrating superior biocompatibility.Conclusion:Rk1/CTX-lip presents a promising new therapy for prostate cancer and holds potential for relieving concurrent fungal infections in cancer patients with low immunity.

关键词： Cabazitaxel Fungal infection Ginsenoside Rk1 liposome-drug delivery system Prostate cancer

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Single-base editing in IGF2 improves meat production and intramuscular fat deposition in liang Guang Small Spotted pigs

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Journal of Animal Science and Biotechnology 2024年第1期15卷 108-126页

作者： tianqi Duo Xiaohong liu Delin Mo Yu Bian Shufang Cai Min Wang Ruiqiang li Qi Zhu Xian Tong Ziyun liang Weilun Jiang Shiyi Chen Yaosheng Chen Zuyong He State Key Laboratory of Biocontrol School of Life SciencesSun Yat-Sen UniversityGuangzhou 510275GuangdongChina Department of Pharmacology(the State‑Province Key Laboratories of Biomedicine‑Pharmaceutics of China Key Laboratory of Cardiovascular ResearchMinistry of Education)College of PharmacyHarbin Medical UniversityHarbin 150081China Hunan Provincial Key Laboratory for Genetic Improvement of Domestic Animal College of Animal Science and TechnologyHunan Agricultural UniversityChangsha 410128China

Background Chinese indigenous pigs are popular with consumers for their juiciness,flavour and meat quality,but they have lower meat production.Insulin-like growth factor 2(IGF2) is a maternally imprinted growth factor that promotes skeletal muscle growth by regulating cell proliferation and differentiation.A single nucleotide polymorphism(SNP) within intron 3 of porcine IGF2 disrupts a binding site for the repressor,zinc finger BED-type containing 6(ZBED6),leading to up-regulation of IGF2 and causing major effects on muscle growth,heart size,and backfat thickness.This favorable mutation is common in Western commercial pig populations,but absent in most Chinese indigenous pig breeds.To improve meat production of Chinese indigenous pigs,we used cytosine base editor 3(CBE3)to introduce IGF2 intron3-C3071T mutation into porcine embryonic fibroblasts(PEFs) isolated from a male liang Guang Small Spotted pig(LGSS),and single-cell clones harboring the desired mutation were selected for somatic cell nuclear transfer(SCNT) to generate the founder line of IGF2^(T/T) pigs.Results We found the heterozygous progeny IGF2^(C/T) pigs exhibited enhanced expression of IGF2,increased lean meat by 18%-36%,enlarged loin muscle area by 3%-17%,improved intramuscular fat(IMF) content by 18%-39%,marbling score by 0.75-1,meat color score by 0.53-1.25,and reduced backfat thickness by 5%-16%.The enhanced accumulation of intramuscular fat in IGF2^(C/T) pigs was identified to be regulated by the PI3K-AKT/AMPK pathway,which activated SREBP1 to promote adipogenesis.Conclusions We demonstrated the introduction of IGF2-intron3-C3071T in Chinese LGSS can improve both meat production and quality,and first identified the regulation of IMF deposition by IGF2 through SREBP1 via the PI3KAKT/AMPK signaling pathways.Our study provides a further understanding of the biological functions of IGF2and an example for improving porcine economic traits through precise base editing.

关键词： CBE3 IGF2 Intramuscular fat Meat production PI3K-AKT/AMPK ZBED6

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