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The biologically and ecologically important natural products from the Chinese sea hare Bursatella leachii:structures,stereochemistry and beyond

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Chinese Journal of Natural Medicines 2024年第11期22卷 1030-1039页

作者： zhang Xinyuan SU Mingzhi ZHU Mingxin CHEN Sha GAO Zhen GUO Yuewei LI xuwen School of Chinese Materia Medica Nanjing University of Chinese MedicineNanjing 210023China State Key Laboratory of Chemical Biology Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

A novel amide alkaloid,bursatamide A(1),featuring an unprecedented propyl-hexahydronaphthalene carbon frame-work,was isolated from the infrequently studied sea hare Bursatella leachi,alongside a new 3-phenoxypropanenitrile alkaloid,bursatellin B(2),and twelve known *** structures of 1 and 2 were elucidated through comprehensive spectroscopic data analyses,while their relative and absolute configurations(ACs)were established through total synthesis and a series of quantum chem-ical calculations,including calculated electronic circular dichroism(ECD)spectra,optical rotatory dispersion(ORD)methods,and DP4^(+) probability *** A(1)demonstrated inhibitory effects against the human pathogenic bacteria Listeria monocyt-ogenes and Vibrio ***-bursatellin B(21),a diastereoisomer of 2,exhibited notable antibacterial activity against the fish pathogenic bacterium Streptococcus parauberis FP KSP28,with an MIC90 value of 0.0472 μg·mL^(-1).

关键词： Bursatella leachii Marine natural product Alkaloid Sea hare Antibacterial activity

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Manganese-based virus-mimicking nanomedicine with triple immunomodulatory functions inhibits breast cancer brain metastasis

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BIOMATERIALS 2025年 320卷 123262-123262页

作者： Zhao, Zhenhao Zhou, Jingyi Li, xuwen zhang, Tongyu Tian, Zonghua Sun, Tao Jiang, Chen Fudan Univ Sch Pharm Dept Pharmaceut Minist EducKey Lab Smart Drug DeliveryState Key Shanghai 201203 Peoples R China MOE Frontiers Ctr Brain Sci Shanghai 201203 Peoples R China Fujian Med Univ Affiliated Hosp 1 Natl Reg Med Ctr Dept Digest Dis Binhai Campus Fuzhou 350212 Peoples R China

Hindered by the challenges of blood-brain barrier (BBB) hindrance, tumor heterogeneity and immunosuppressive microenvironment, patients with breast cancer brain metastasis have yet to benefit from current clinical treatments, experiencing instead a decline in quality of life due to radiochemotherapy. While virus-mimicking nanosystems (VMN) mimicking viral infection processes show promise in treating peripheral tumors, the inability to modulate the immunosuppressive microenvironment limits the efficacy against brain metastasis. Accordingly, a VMN-based triple immunomodulatory strategy is initially proposed, aiming to activate innate and adaptive immune responses and reverse the immunosuppressive microenvironment. Here, manganese-based virus-mimicking nanomedicine (Vir-HD@HM) with intratumoral drug enrichment is engineered. Vir-HD@HM can induce the immune response through the activation of cGAS-STING by mimicking the in vivo infection process of herpesviruses. Meanwhile, DNAzyme mimicking the genome can rescue the epigenetic silencing of PTEN with the assistance of Mn2+, thus ameliorating the immunosuppressive metastatic microenvironment and achieving synergistic sensitizing therapeutic efficacy. In vivo experiments substantiate the efficacy of VirHD@HM in recruiting NK cells and CD8+ T cells to metastatic foci, inhibiting Treg cells infiltration, and prolonging murine survival without adjunctive radiochemotherapy. This study demonstrates that Vir-HD@HM with triple immunomodulation offers an encouraging therapeutic option for patients with brain metastasis.

关键词： Breast cancer brain metastasis Virus-mimicking nanosystem Immune activation Immunosuppressive microenvironment regulation PTEN cGAS-STING

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Surface-Defect-Involved and Eye-Visible Electrochemiluminescence of Unary Copper Nanoclusters for Immunoassay

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ANALYTICAL CHEMISTRY 2023年第8期95卷 4155-4161页

作者： Wang, Dongyang Gao, xuwen Ren, Xiaoxuan zhang, Bin Zou, Guizheng Shandong Univ Sch Chem & Chem Engn Jinan 250100 Peoples R China

A single-stabilizer-capped strategy is proposed for achieving highly efficient and surface-defect-involved electro-chemiluminescence (ECL) from unary copper nanoclusters (NCs) via employing L-cysteine (Cys) as a capping agent of luminophore. The Cys-capped CuNCs (Cys-CuNCs) can be electrochemically injected with valence band (VB) holes and exhibit eye-touchable ECL processes around +0.95 and +1.15 V upon employing TPrA as a coreactant. Both accumulated ECL spectra and spooling ECL spectra demonstrated that the two ECL processes are of the same single waveband and spectrally identical to each other with the same maximum emission wavelength of 640 nm. Promisingly, ECL of the Cys-CuNCs/TPrA system is obviously red-shifted for similar to 150 nm to PL of Cys-CuNCs, indicating that the bandgap-engineered routes for ECLs of Cys-CuNCs are completely blocked. The oxidative-reduction ECL process of the Cys-CuNCs/TPrA system is a kind of highly efficient, eye-visible, and single-color emission in surface-defect-involved route. The capping agent of Cys can enable the CuNCs/TPrA system with a stronger ECL than other thiol capping agents, so that Cys-CuNCs are utilized as ECL tags for sensitive and selective immunoassays, which exhibit a wide linear response range from 0.05 pg/mL to 0.5 ng/ mL and a limit of detection of 0.01 pg/mL (S/N = 3) with carcinoembryonic antigen as the analyte. Moreover, both the luminophore Cys-CuNCs and conjugates Ab2-CuNCs can be safely stored in aqueous media without any protector, which is promising for the evolution and clinic application of metal NC ECL in the surface-defect-involved route.

关键词： Cysteine Electrochemiluminescence Immunoassay

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Potential-selective electrochemiluminescence of AgInS2/ZnS nanocrystals and its immunoassay application

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CHEMICAL COMMUNICATIONS 2024年第37期60卷 4958-4961页

作者： Li, Mengwei Gao, xuwen Ren, Xiaoxuan Ai, Yaojia zhang, Bin Zou, Guizheng Shandong Univ Sch Chem & Chem Engn Jinan 250100 Peoples R China

Potential-selective electrochemiluminescence (ECL) with tunable maximum-emission-potential ranging from 0.95 to 0.30 V is achieved using AgInS2/ZnS nanocrystals, which is promising in the design of multiplexed bioassay on commercialized ECL setups. The model system AgInS2/ZnS/N2H4 exhibits efficient ECL around 0.30 V and can be exploited for sensitive immunoassays with less electrochemical interference and crosstalk.

关键词： Nanocrystals

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腹水的影像学表现及鉴别诊断

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中国中西医结合影像学杂志 2023年第5期21卷 595-600页

作者：范金蕾左立平王博文安悦铭张戌雯赵倩温馨于德新山东大学齐鲁医院放射科山东济南250012 山东省济南市济南医院影像科山东济南250013 山东省滨州市第二人民医院放射科山东滨州256800

腹水是多种疾病的合并症,病因复杂,可分为恶性腹水、感染性腹水、乳糜性腹水及其他原因腹水。影像学检查是诊断腹水的有效方法,可清晰显示腹水含量、衰减值、分布范围及腹膜和周围脏器改变。介绍不同病因腹水的CT、MRI表现,以期提高对... 详细信息

腹水是多种疾病的合并症,病因复杂,可分为恶性腹水、感染性腹水、乳糜性腹水及其他原因腹水。影像学检查是诊断腹水的有效方法,可清晰显示腹水含量、衰减值、分布范围及腹膜和周围脏器改变。介绍不同病因腹水的CT、MRI表现,以期提高对腹水的诊断和鉴别水平,从而指导临床评估病情、改善患者预后。

关键词：腹水诊断显像诊断鉴别

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Design of Wide-Range High-Precision Cesium Oven Temperature Control System for Time-Keeping Cesium Beam Frequency Standards

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APPLIED SCIENCES-BASEL 2025年第3期15卷 1128-1128页

作者： Liu, Jie Li, Xiaofeng Li, Chao Hu, xuwen Li, Qingyue Sun, Fuyu zhang, Shougang Chinese Acad Sci Natl Time Serv Ctr 3 East Shuyuan Rd Xian 710600 Peoples R China Nanchang Univ Sch Phys & Mat Sci Nanchang 330031 Peoples R China Chinese Acad Sci Key Lab Time Reference & Applicat 3 East Shuyuan Rd Xian 710600 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

The temperature fluctuation of a cesium oven has a significant impact on the performance of time-keeping cesium beam frequency standards. We have designed a circuit system for the precise temperature control of the cesium oven used in it. The use of a 24-bit analog-to-digital converter ensures a temperature measurement resolution more than 0.5 mK within the working range. The digital PID algorithm guarantees the accuracy of error signal computation, and a 16-bit digital-to-analog converter improves the resolution of the control current adjustment. Ultimately, we achieved the goal of keeping the temperature fluctuation of the cesium oven to less than 4 mK within a working range of 120 degrees C. The results indicate that the circuit system effectively ensures the performance of the cesium beam frequency standard.

关键词： time-keeping cesium beam frequency standards cesium oven temperature control digital PID

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Accuracy analysis of traditional acupoint location and the coincidence of cutaneous arterial perforators and acupoints

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CLINICAL ANATOMY 2024年第7期37卷 701-709页

作者： Guo, Chunxia zhang, Yongguang Ding, Zhiwei Han, Rong Jiao, xuwen Hu, Jinlian City Univ Hong Kong Dept Biomed Engn Hong Kong Peoples R China Weifang Chinese Med Hosp Dept Acupuncture & Tuina Weifang Peoples R China Weifang Peoples Hosp Dept Hand & Foot Orthoped Weifang Peoples R China Gaomi Peoples Hosp Med Cosmet Ctr Gaomi Peoples R China Gaomi Peoples Hosp Dept Hand & Foot Orthoped Gaomi Peoples R China City Univ Hong Kong Dept Biomed Engn Kowloon Tong 83 Tat Chee Ave Hong Kong Peoples R China Gaomi Peoples Hosp Med Cosmet Ctr 77 Zhenfu St Gaomi 261500 Shandong Peoples R China Gaomi Peoples Hosp Dept Hand & Foot Orthoped 77 Zhenfu St Gaomi 261500 Shandong Peoples R China

Several reports have shown a coincidence relationship between perforators and acupoints. However, there have been few previous reports of objective experimental methods to verify the reliability of the accuracy of acupoint location (APL) with nearby perforators. This research aimed to determine the internal agreement of the APL of five acupuncturists and to analyze the coincidence rate of acupoints with nearby perforators. Three two healthy volunteers were recruited with the inclusion and exclusion criteria. Three TCM clinical physicians determined acupoints in areas of the lower limb of participants. Two microsurgeons sketched corresponding regions based on the most common skin flap operation sites, located bone markers, and drew the skin flap axis. Doppler ultrasound was used to mark the perforator point and the distances measured for both points. There is no significant difference in the distance between the acupoints and perforators localization in different groups, and there are significant differences between the angle formed by acupoints and penetrators in all groups. All the points located by the traditional Chinese medicine (TCM) therapists are distributed around the dot. The distance between the coordinate point (A-B) of 溫溜 Wenliu (LI7) localization is the largest, reaching 16.6 mm. The accuracy of the acupoint location of each physician is limited by the clinical experience of physicians, and the difference among them is significant. There is a certain correspondence between the location of acupoints and perforators, which needs further studies to confirm.

关键词： acupoint location acupoints cutaneous arterial perforators traditional Chinese medicine

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Model Predictive Path Planning of AGVs: Mixed Logical Dynamical Formulation and Distributed Coordination

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IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS 2023年第7期24卷 6943-6954页

作者： Xin, Jianbin Wu, xuwen D'Ariano, Andrea Negenborn, Rudy zhang, Fangfang Zhengzhou Univ Sch Elect & Informat Engn Zhengzhou 450001 Peoples R China Roma Tre Univ Dept Civil Comp Sci & Aeronaut Technol Engn I-00146 Rome Italy Delft Univ Technol Dept Marine & Transport Technol NL-2628 CD Delft Netherlands

Most of the existing path planning methods of automated guided vehicles (AGVs) are static. This paper proposes a new methodology for the path planning of a fleet of AGVs to improve the flexibility, robustness, and scalability of the AGV system. We mathematically describe the transport process as a dynamical system using an ad hoc mixed logical dynamical (MLD) model. Based on our MLD model, model predictive control is proposed to determine the collision paths dynamically, and the corresponding optimization problem is formulated as 0-1 integer linear programming. An alternating direction method of multipliers (ADMM)-based decomposition technique is then developed to coordinate the AGVs and reduce the computational burden, aiming for real-time decisions. The proposed methodology is tested on industrial scenarios, and results from numerical experiments show that the proposed method can obtain high transport productivity of the multi-AGV system at a low computational burden and deal with uncertainties resulting from the industrial environment.

关键词： Path planning Planning Task analysis Robots Predictive models Mathematical models Robot kinematics Automated guided vehicles path planning model predictive control mixed logical dynamical model

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Optimizing Carbon Dioxide Injection for Methane Hydrate Development and Carbon Sequestration: A Long-Term Numerical Simulation Study

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ENERGY & FUELS 2024年第21期38卷 20629-20643页

作者： zhang, Zhaobin Li, Yuxuan Xu, Tao Li, Shouding Li, Xiao Lu, Cheng Qin, xuwen Chinese Acad Sci Key Lab Shale Gas & Geoengn Inst Geol & Geophys Beijing 100029 Peoples R China Chinese Acad Sci Inst Earth Sci Beijing 100049 Peoples R China Univ Chinese Acad Sci Coll Earth & Planetary Sci Beijing 100049 Peoples R China Minist Nat Resources China Geol Survey Oil & Gas Resources Survey Beijing 100083 Peoples R China Natl Engn Res Ctr Gas Hydrate Explorat & Dev Guangdong 510075 Peoples R China China Geol Survey China Aero Geophys Survey & Remote Sensing Ctr Nat Beijing 100083 Peoples R China

Although in theory, carbon dioxide replacement for methane hydrate development can simultaneously enhance methane production rates and achieve carbon sequestration, its feasibility under field conditions has not been thoroughly investigated. This study proposes a carbon dioxide injection and methane development replacement strategy using a multiwell injection and production system. A custom-developed hydrate simulator was used to model the replacement process and its long-term evolution over 100,000 years. The results indicate that for shallowly buried hydrate reservoirs in seafloor sediments, carbon dioxide injection can significantly enhance methane production rates. The resulting carbon dioxide hydrates remain stable after the reservoir temperature and pressure recover, which facilitating carbon sequestration. Analysis of reservoir conditions reveals that carbon dioxide replacement is less effective for deeply buried methane hydrate reservoirs. Additionally, shallower water depths and intact seal integrity are favorable for carbon dioxide replacement. To achieve optimal replacement, the carbon dioxide injection rate must be carefully controlled;both excessive injection rates and premature injection can lead to carbon dioxide breakthrough from the injection well to the production well. Overall, this study provides insights into the feasibility analysis, site selection, and operational optimization for carbon dioxide replacement in methane hydrate development and carbon sequestration.

关键词： Carbon sequestration

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Combined Separated Oscillatory Fields Technique 37

Combined Separated Oscillatory Fields Technique

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37th European Frequency and Time Forum, EFTF 2024

作者： Sun, Fuyu Li, Chao Hu, xuwen zhang, Shougang National Time Service Center Chinese Academy of Sciences Xi'an China Chinese Academy of Sciences Key Laboratory of Time Reference and Applications Xi'an China

ISBN: (纸本)9798350354270

Ramsey's method of separated oscillatory fields (SOFs) has been originally used in beam magnetic resonance apparatuses, which leads to the establishment of atomic definition of time interval and frequency. Since then, various versions of the SOFs technique have been widely used for precise measurement of different physical quantities. Here, we present an alternative method to generate atomic beam magnetic resonance signals by combining two Ramsey cavities with phase differences of 0 and 1t. It is found that the strength of the resonance signals generated using this combined SOFs technique is approximately twice that of the resonance signals produced by the conventional SOFs techniques. In addition to generating stronger resonance, the combined Ramsey method eliminates the Rabi background superimposed on the Ramsey interference pattern without increasing the Ramsey signal linewidth. Thus, this technique serves a promising tool for high-precision measurements. © 2024 IEEE.

关键词： Velocity measurement

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