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Ultrastructure of Ediacaran cloudinids suggests diverse taphonomic histories and affinities with non-biomineralized annelids

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SCIENTIFIC REPORTS 2020年第1期10卷 535-535页

作者： Yang, Ben Steiner, Michael Schiffbauer, James D. Selly, Tara Wu, xuwen zhang, Cong Liu, Pengju Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China Free Univ Berlin Dept Earth Sci D-12249 Berlin Germany Univ Missouri Dept Geol Sci Columbia MO 65211 USA Univ Missouri Xray Microanal Core Facil Columbia MO 65211 USA Chinese Acad Sci Inst Oceanol Lab Marine Organism Taxon & Phylogeny Qingdao 266071 Peoples R China Shandong Univ Sci & Technol Sch Earth Sci & Engn Qingdao 266590 Peoples R China

Cloudinids have long been considered the earliest biomineralizing metazoans, but their affinities have remained contentious and undetermined. Based on well-preserved ultrastructures of two taxa, we here propose new interpretations regarding both their extent of original biomineralization and their phylogenetic affinity. One of these taxa is a new cloudinid from Mongolia, Zuunia chimidtsereni gen. et sp. nov., which exhibits key characteristics of submicrometric kerogenous lamellae, plastic tubewall deformation, and tube-wall delamination. Multiple carbonaceous lamellae are also discovered in Cloudina from Namibia and Paraguay, which we interpret to have originated from chitinous or collagenous fabrics. We deduce that these cloudinids were predominantly originally organic (chitinous or collagenous), and postmortem decay and taphonomic mineralization resulted in the formation of aragonite and/or calcite. Further, based on our ultrastructural characterization and other morphological similarities, we suggest that the cloudinids should most parsimoniously be assigned to annelids with originally organic tubes.

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单细胞测序结合机器学习算法揭示心力衰竭病人细胞间通讯及关键调控基因

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中西医结合心脑血管病杂志 2025年第4期23卷 525-538页

作者：王学付饶晋张立刘旭雯张宇峰上海理工大学健康科学与工程学院上海200093 海军军医大学附属长征医院上海200003 广西大学医学院

目的:基于单细胞测序和机器学习算法构建心力衰竭(HF)的诊断模型,并探索HF病人中细胞间通讯。方法:使用Seurat包对单细胞转录组测序(scRNA-seq)数据质控、降维、聚类和注释。通过AUCell评估各细胞亚群的免疫活性,选择免疫活性最高的细... 详细信息

目的:基于单细胞测序和机器学习算法构建心力衰竭(HF)的诊断模型,并探索HF病人中细胞间通讯。方法:使用Seurat包对单细胞转录组测序(scRNA-seq)数据质控、降维、聚类和注释。通过AUCell评估各细胞亚群的免疫活性,选择免疫活性最高的细胞亚群进行后续分析。基于批量转录组测序(Bulk RNA-seq)数据,使用limma包筛选差异表达基因并进行基因集富集分析(GSEA)。进一步将疾病分类被作为反应变量,差异基因作为解释变量,通过4种机器学习模型来筛选具有诊断价值的巨噬细胞相关特征基因,并通过受试者工作特征(ROC)曲线评估关键基因的诊断能力。构建列线图预测HF发生的总风险分数。最后使用CellChat来探索细胞亚群之间的细胞间相互作用。结果:与正常样本相比,HF病人中巨噬细胞的比例高于正常样本,且巨噬细胞免疫活性评分最高。巨噬细胞亚群差异基因富集分析表明,白细胞介导的免疫过程和抗原的处理和呈递显著富集。多种机器学习算法相交结果发现SERPINA3、GPAT3、ANPEP和FCGBP可作为特征基因并与巨噬细胞密切相关。ROC曲线表明,诊断模型具有很好的预测能力。细胞通讯发现,由巨噬细胞移动抑制因子(MIF)介导的成纤维细胞-巨噬细胞以及ANNEXIN介导的巨噬细胞-中性粒细胞之间的信号通路表现出复杂的传出和传入动力学。结论:4个关键基因作为生物标志物具有良好的诊断价值。巨噬细胞介导的免疫过程以及细胞间通讯在HF的免疫微环境中起着关键作用。

关键词：心力衰竭单细胞测序机器学习诊断模型细胞通讯

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南海天然气水合物试采储层热流耦合与温度场调控研究进展

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地质学报 2024年第11期98卷 3213-3224页

作者：秦绪文陆程张召彬王平康李守定董艳辉马超何玉发庞守吉中国自然资源航空物探遥感中心北京100083 中国地质调查局油气资源调查中心北京100083 自然资源部青海木里天然气水合物与冻土环境野外科学观测研究站北京100083 天然气水合物勘查开发国家工程技术研究中心广东广州510075 中国科学院地质与地球物理研究所北京100029 中国地质调查局北京100037 中国地质调查局广州海洋地质调查局广东广州510075 中海油研究总院有限责任公司北京100028

中国南海天然气水合物储层类型以泥质粉砂为主,与其他国家和地区的砂质储层相比开采难度大。本文针对南海北部泥质粉砂天然气水合物降压开采涉及的相变习性演化、有效渗透率变化、热流耦合模式、试采系统温度场调控与矿场尺度增温防冰... 详细信息

中国南海天然气水合物储层类型以泥质粉砂为主,与其他国家和地区的砂质储层相比开采难度大。本文针对南海北部泥质粉砂天然气水合物降压开采涉及的相变习性演化、有效渗透率变化、热流耦合模式、试采系统温度场调控与矿场尺度增温防冰等关键问题,综述了笔者团队近年来取得的最新研究成果。研究表明,泥质粉砂型水合物相变始终处于动态平衡状态,储层因富含黏土水合物相变滞后效应明显;试采井壁处节流膨胀效应强烈,“温度漏斗”斜率最大,一旦形成“水锁”与生成二次水合物,气相渗流能力将明显降低;在无外部热源补给情况下,较高的产气速率,易造成水合物分解速率减缓直至停止分解,中国南海泥质粉砂水合物分解主要受传热控制模式影响,亟需建立有效的“储层-井筒”试采系统多元温压调控与安全流动机制,提高产气效率;依托自然资源部青海木里天然气水合物与冻土环境野外科学观测研究站,利用原位补热降压充填的水合物开采方法,成功完成矿场尺度水合物试采系统温度场改造试验,进一步优化提高了储层渗流能力,实现了增渗扩产目的。

关键词：泥质粉砂试采系统相变习性热流耦合温度场改造

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竖向分布钢筋不连续的装配式剪力墙结构振动台试验研究

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建筑结构学报 2022年第7期43卷 91-99页

作者：蔡琪宋晓滨肖绪文顾祥林张士前廖显东苏群山同济大学土木工程学院上海200092 中国建筑股份有限公司北京100029 中国建筑第八工程局有限公司上海200122 河南省第二建设集团有限公司河南郑州451464

为研究竖向分布钢筋不连续的装配式剪力墙结构抗震性能,设计了1个缩尺比为1/2的四层模型结构,并对其开展振动台试验。试验中考虑了7度多遇至9度罕遇等地震烈度(0.035g~0.62g),并进行了峰值加速度0.80g的El Centro波破坏加载。研究结果表... 详细信息

为研究竖向分布钢筋不连续的装配式剪力墙结构抗震性能,设计了1个缩尺比为1/2的四层模型结构,并对其开展振动台试验。试验中考虑了7度多遇至9度罕遇等地震烈度(0.035g~0.62g),并进行了峰值加速度0.80g的El Centro波破坏加载。研究结果表明:在7度罕遇地震作用下,模型结构处于弹性状态,最大层间位移角仅1/991;模型结构进入塑性阶段后(8度罕遇和9度罕遇地震作用),现浇边缘构件产生水平裂缝并跨越竖向拼缝向预制墙体发展,模型结构频率和阻尼比大幅变化,最大层间位移角为1/125;在峰值加速度0.80g的El Centro波作用下,模型结构发生典型的压弯破坏,一层现浇边缘构件混凝土局部压坏,钢筋压曲,但未发生整体破坏或倒塌;模型结构的1阶频率和阻尼比分别降低58.3%和增大163.2%,层间位移角达1/87;该剪力墙结构整体变形呈弯曲型,其现浇边缘构件和预制墙体具有良好的协同工作能力,抗震性能良好。

关键词：装配式剪力墙竖向分布钢筋不连续振动台试验抗震性能

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Prediction of hypertensive disorders in pregnancy based on placental growth factor

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TECHNOLOGY AND HEALTH CARE 2021年第1_suppl期29卷 S165-S170页

作者： Xu, Qi Sun, Ge zhang, Song Liu, Guoli Yang, Lin Meng, Yu Chen, Aiqing Yang, Yimin Li, xuwen Hao, Dongmei Liu, Xiaohong Shao, Jing Peking Univ Peoples Hosp Beijing 100044 Peoples R China Beijing Univ Technol Fac Environm & Life Sci Beijing 100124 Peoples R China Beijing Int Sci & Technol Cooperat Base Intellige Beijing 100124 Peoples R China Beijing Yes Med Devices Co Ltd Beijing 100152 Peoples R China

BACKGROUND: The prediction of hypertensive disorders in pregnancy (HDP) mainly involves various aspects such as maternal characteristics and biomarkers. OBJECTIVE: We aimed to study the effect of the HDP prediction model with or without placental growth factor (PlGF). METHODS: This study used maternal factors and PlGF, and standardized the data uniformly. At 12-20 weeks, the comprehensive comparison of model quality with or without PlGF was conducted by logistic regression. RESULTS: The area under curve and the model accuracy of the model with PlGF were higher than those of the model without PlGF. The accuracy of the model with PlGF was above 90%. CONCLUSIONS: Adding PlGF to the model for predicting HDP improved the accuracy and effectiveness of the model. This study confirmed the predictive performance of PlGF.

关键词： Model accuracy placental growth factor logistic regression

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用于低相干干涉测量系统的多通道数字与模拟信号同步采集方法研究

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机床与液压 2024年第15期52卷 137-142页

作者：丁斌何飞飞毛敏祖洪飞陈骏张翔陈旭雯南通市计量检定测试所江苏南通226007 浙江理工大学机械学院浙江杭州310018 浙江谱麦科技有限公司浙江宁波315048 浙江龙宇智能科技有限公司浙江海宁314419

在现代工程领域中,模拟信号和数字信号同步采集的重要性变得越来越显著。同步采集这两种类型的信号可以提高数据采集和处理的准确性、可靠性,并避免数据延迟、抖动等问题,尤其对于一些特定应用场景具有极高的必要性。为了适应低相干干... 详细信息

在现代工程领域中,模拟信号和数字信号同步采集的重要性变得越来越显著。同步采集这两种类型的信号可以提高数据采集和处理的准确性、可靠性,并避免数据延迟、抖动等问题,尤其对于一些特定应用场景具有极高的必要性。为了适应低相干干涉测量系统中多类型多路信号的同步采集与处理需求,基于已有的数据采集仪,设计并制作了数字信号调理板,并通过实验验证了数字信号与模拟信号的同步采集情况。实验结果表明:所设计的系统不仅可以实现两种信号的高速同步采集,而且系统整体位移采集的精度很高:电动位移台在0~70 mm行程内,系统测量值与干涉仪测量值最大误差为2.52μm;压电位移台在0~320μm内,系统测量值与干涉仪测量值最大误差仅为0.54μm。

关键词：同步采集模拟信号数字信号低相干干涉光栅调理

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Advances in Multimodal Imaging Techniques for Evaluating and Predicting the Efficacy of Immunotherapy for NSCLC

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Cancer Management and Research 2025年 17卷 1073-1086页

作者： Jingyi Liu Mei Xie Jing Shen Jie Yao xuwen Lin Xinyu Bao Xin zhang Yiran Liang Yun Yang Gege Jiang Ximeng Diao Wenya Han Hai Du Xinying Xue Jianlin Wu Department of Radiology Affiliated Zhongshan Hospital of Dalian University Dalian 116001 People’s Republic of China Department of Respiratory and Critical Care Emergency and Critical Care Medical Center Beijing Shijitan Hospital Capital Medical University Beijing 100038 People’s Republic of China Department of Respiratory and Critical Care Affiliated Hospital of Shandong Second Medical University Weifang People’s Republic of China Department of Respiratory and Critical Care Medicine Taihe Hospital Hubei University of Medicine Shiyan 442000 People’s Republic of China Ordos Central Hospital Ordos City 017000 People’s Republic of China Department of Respiratory and Critical Care Xuanwu Hospital Capital Medical University Beijing 100038 People’s Republic of China

Immunotherapy has emerged as a transformative treatment for non-small cell lung cancer (NSCLC), yet its clinical benefits remain variable among patients. Early and accurate evaluation of treatment response is critical to guide therapeutic adjustments and improve outcomes. This review synthesizes recent advancements in multimodal imaging techniques—computed tomography (CT), positron emission tomography (PET)/CT, magnetic resonance imaging (MRI), and radiomics—for evaluating and predicting immunotherapy efficacy in NSCLC. We analyze the strengths and limitations of conventional morphological criteria (eg, RECIST, iRECIST) and highlight emerging quantitative biomarkers, including CT texture analysis, metabolic parameters (MTV, TLG), and diffusion-weighted MRI metrics. Notably, radiomics demonstrates promise in decoding tumor heterogeneity, PD-L1 expression, and immune microenvironment features, while immuno-PET probes targeting immune checkpoints offer novel insights into immune activity in vivo. Challenges such as pseudo-progression, nodal immune flare, and discrepancies between imaging responses and pathological responses are critically discussed. By integrating morphological, metabolic, and microenvironmental data, multimodal imaging enhances precision in patient stratification and therapeutic monitoring. Future research should prioritize multicenter, AI-driven radiomics validation and targeted tracer development to optimize NSCLC immunotherapy management. This review provides clinicians and researchers with new directions for utilizing multimodal imaging techniques in developing personalized treatment strategies.

关键词： non-small cell lung cancer immunotherapy efficacy prediction CT PET MRI

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A novel calcium phosphate-based nanocomposite for the augmentation of cement-injectable cannulated pedicle screws fixation: A cadaver and biomechanical study

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JOURNAL OF ORTHOPAEDIC TRANSLATION 2020年 20卷 56-66页

作者： Sun, Haolin Liu, Chun Li, xuwen Liu, Huiling zhang, Weiguang Yang, Huilin Li, Chunde Yang, Lei Peking Univ Dept Orthoped Hosp 1 8 Xishiku St Beijing 100034 Peoples R China Soochow Univ Inst Orthoped Dept Orthoped Suzhou Peoples R China Peking Univ Sch Basic Med Sci Dept Human Anat 38 Xueyuan Rd Beijing 100191 Peoples R China Hebei Univ Technol Ctr Hlth Sci & Engn Sch Mat Sci & Engn Tianjin Key Lab Mat Laminating Fabricat & Interfa Tianjin Peoples R China

Background/objective: Both polymethylmethacrylate (PMMA) and traditional calcium phosphate-based cements have some deficiencies as augmentation materials for pedicle screw fixation. Here, a novel calcium phosphate-based nanocomposite (CPN) for the augmentation of pedicle screw fixation was developed based on previous study, and the handling properties, biomechanical performance, and biodegradation behaviour of CPN were evaluated and compared with clinical PMMA by means of a cadaver study and animal tests. Methods: Bone mineral density of the lumbar vertebrae was tested. Pedicle screws were placed into the lumbar vertebrae under the guidance of three dimensionally printed templates;each of which was designed based on computed tomography (CT) reconstruction of each vertebrae and augmented with either PMMA or CPN. X-ray and CT scan were used to evaluate the accuracy of screw placement and dispersion as well as interdigitation of bone cement. The axial pull-out strength and maximum torque were tested using a mechanical testing machine. Degradation behaviour of CPN was evaluated by in vitro immersion tests for 8 weeks and in vivo rabbit femur defect model for up to 6 months, respectively. Results: Standard mechanical tests revealed that PMMA was much stronger than CPN after setting (compressive strength 95 vs. 49 MPa, respectively, p < 0.001). Results of the projection area and volume distribution of cement along the distal end of the screws revealed that CPN exhibited unique dispersing and interdigitation abilities compared with PMMA. Specifically, CPN dispersed uniformly and symmetrically along the screw, while PMMA was limited to the proximal part of the screw. Axial pull-out test results showed that the axial pull-out strengths of CPN- and PMMA-augmented pedicle screws were similar (1199 +/- 225 N vs 1337 +/- 483 N, respectively) and not significantly different (p = 0.47), although CPN was an intrinsically weaker material than PMMA. Similarly, CPN showed average torq

关键词： Calcium phosphate-based cement Injectable Osteoporosis Pedicle screw PMMA

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Development of a high-temporal resolution neutron flux measurement system for the HL-2M tokamak

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JOURNAL OF INSTRUMENTATION 2022年第7期17卷 P07027页

作者： zhang, Jie zhang, Yipo zhang, Jinglong Zhou, Jianhang Zhan, xuwen Wen, Zuowei Cheng, Shikui Zhu, Yuxuan Yuan, Guoliang Liu, Yuhang Yang, Qiulei Chen, Wei Shi, Zhongbing Liu, Yi Xu, Min Southwestern Inst Phys POB 432 Chengdu 610041 Peoples R China Chengdu Univ Technol Coll Nucl Technol & Automat Engn Chengdu 610059 Peoples R China

To enhance the understanding of the physics of energetic ions in fusion plasma, a high-temporal resolution neutron flux measurement (HTRNFM) system, which is equipped with a fast-neutron scintillation detector embedded with ZnS:Ag phosphor, has been developed for the HL-2M tokamak. It has a temporal resolution of 10 mu s during conventional operations. Its dynamic range is sufficiently wide for neutron flux measurements by adopting the combination use of the scalar mode and the Campbell mode. Based on the Monte Carlo calculations, the applicable count rate ranges of both the scalar mode and the Campbell mode are respectively 0.1-10 Mcps and 10-200 Mcps. The performance validation of the HTRNFM system has been performed by neutron flux measurements in magnetohydrodynamic (MHD) quiet plasmas in the HL-2A tokamak. In another plasma with abundant MHD instabilities, both the continuous neutron flux decreases and the rapid neutron flux decreases caused by different MHD instabilities are observed in a more detailed manner for the first time with the HTRNFM system than with other neutron flux measurement (NFM) systems that have a lower temporal resolution of 1 ms. The HTRNFM system will serve as a powerful diagnostic tool for research on energetic ion confinement quality in the HL-2M tokamak.

关键词： Nuclear instruments and methods for hot plasma diagnostics Neutron detectors (cold, thermal, fast neutrons) Simulation methods and programs

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Click-Nucleic-Acid-Containing Codelivery System Inducing Collapse of Cellular Homeostasis for Tumor Therapy through Bidirectional Regulation of Autophagy and Glycolysis

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ACS APPLIED MATERIALS & INTERFACES 2020年第52期12卷 57757-57767页

作者： Guo, Qin Chen, Qinjun zhang, Yujie Zhou, Wenxi Li, xuwen Li, Chao zhang, Yiwen Chen, Hongyi Liu, Peixin Chu, Yongchao Sun, Tao Jiang, Chen Fudan Univ State Key Lab Med Neurobiol Key Lab Smart Drug Delivery Minist Educ Shanghai 201203 Peoples R China Fudan Univ MOE Frontiers Ctr Brain Sci Sch Pharm Dept Pharmaceut Shanghai 201203 Peoples R China

As a rapid proliferating tissue, tumor cells have to optimize nutrient utilization to withstand harsh conditions. Several approaches have been explored to inhibit the growth and metastasis of tumor by disrupting the reprogrammed tumor metabolism. However, nutrient limitations within solid tumors may induce the metabolic flexibility of malignant cells to sustain growth and survival using one nutrient to fill metabolite pools normally supplied by the other. To overcome this predicament, a promising click-nucleic-acid-containing platform for codelivery of rapamycin, anti-PFKFB4 siRNA, and targeting ligand aptamer AS1411 was applied. PFKFB4 could act as a promising target for tumor therapy for being a molecular fulcrum that could couple glycolysis to autophagy by promoting aggressive metastatic tumors. The downregulation of PFKFB4 can help inhibit the SRC3/Akt/mTOR pathway, leading autophagy to the direction of promoting apoptosis of tumor cells, which is induced by the collapse of tumor cellular homeostasis, while low dosages of rapamycin could decrease surgery-induced immune dysfunction. Enhanced tumor autophagy, favorable in vivo antitumor efficacy, and effective systematic immune activation are observed after treatment, suggesting that autophagy and glycolysis can serve as an integrated target for tumor treatment.

关键词： tumor metabolism codelivery click nucleic acid immune activation tumor therapy

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