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动态全场光学相干断层扫描结合深度学习在肿瘤患者术中诊断的应用:一项乳腺癌患者的前瞻性队列研究

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Science Bulletin 2024年第11期69卷 1748-1756页

作者：张舒玮杨滨杨后圃赵进张原媛高元绪 Olivia Monteiro 张康刘博王殊 Breast Center Peking University People’s HospitalBeijing 100044China China ESG Institute Capital University of Economics and BusinessBeijing 100070China Faculty of Information Technology Beijing University of TechnologyBeijing 100124China Department of Pathology Peking University People’s HospitalBeijing 100044China Center for Biomedicine and Innovations Faculty of MedicineMacao University of Science and TechnologyMacao 999078China College of Future Technology Peking UniversityBeijing 100091China School of Mathematical and Computational Sciences Massey UniversityAuckland 0745New Zealand

An intraoperative diagnosis is critical for precise cancer surgery. However, traditional intraoperative assessments based on hematoxylin and eosin(H&E) histology, such as frozen section, are time-,resource-, and labor-intensive, and involve specimen-consuming concerns. Here, we report a near-real-time automated cancer diagnosis workflow for breast cancer that combines dynamic full-field optical coherence tomography(D-FFOCT), a label-free optical imaging method, and deep learning for bedside tumor diagnosis during surgery. To classify the benign and malignant breast tissues, we conducted a prospective cohort trial. In the modeling group(n = 182), D-FFOCT images were captured from April 26 to June 20, 2018, encompassing 48 benign lesions, 114 invasive ductal carcinoma(IDC), 10 invasive lobular carcinoma, 4 ductal carcinoma in situ(DCIS), and 6 rare tumors. Deep learning model was built up and fine-tuned in 10,357 D-FFOCT patches. Subsequently, from June 22 to August 17, 2018, independent tests(n = 42) were conducted on 10 benign lesions, 29 IDC, 1 DCIS, and 2 rare tumors. The model yielded excellent performance, with an accuracy of 97.62%, sensitivity of 96.88% and specificity of 100%;only one IDC was misclassified. Meanwhile, the acquisition of the D-FFOCT images was non-destructive and did not require any tissue preparation or staining procedures. In the simulated intraoperative margin evaluation procedure, the time required for our novel workflow(approximately 3 min)was significantly shorter than that required for traditional procedures(approximately 30 min). These findings indicate that the combination of D-FFOCT and deep learning algorithms can streamline intraoperative cancer diagnosis independently of traditional pathology laboratory procedures.

关键词： Cancer diagnosis Breast neoplasms Dynamic full-field optical coherence tomography Deep learning Image classification

基于双目视觉和圆形标记点的发动机位移精确测试技术

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航空学报 2024年第11期45卷 158-167页

作者：高玉闪闫松张志伟西安航天动力研究所西安710100 航天液体动力全国重点实验室西安710100

为了精确测量发动机静力试验和摇摆试验中结构的三维变形,提出一种基于双目视觉和圆形标记点的高精度位移测量方法,通过在发动机结构表面粘贴反光圆形标记点,并拍摄结构变形过程中的图像序列来识别位移。首先,使用Sobel边缘检测算法提... 详细信息

为了精确测量发动机静力试验和摇摆试验中结构的三维变形,提出一种基于双目视觉和圆形标记点的高精度位移测量方法,通过在发动机结构表面粘贴反光圆形标记点,并拍摄结构变形过程中的图像序列来识别位移。首先,使用Sobel边缘检测算法提取每个圆形标记点的像素级边缘信息;然后,通过基于插值的亚像素边缘检测方法获取亚像素级边缘点,以更准确地确定标记点的位置;最后,利用椭圆最小二乘法对标记点的边缘轮廓进行拟合,从而实现对标记点的精确定位。为了评估该方法的性能,对隔振云台上的静止标记点进行了位移测量。当相机距离标记点0.6 m时,面内2个方向的位移测量标准差分别为0.36μm和0.32μm,离面位移的测量标准差为0.58μm。此外,通过使用位移台提供的标准位移,进一步验证了该算法在处理与相机平面夹角达60°斜面和?12 mm细管路等结构位移测量时的适用性。将该视觉测量系统应用于某发动机机架的静力试验,取得了令人满意的结果。试验表明,该算法能够实时跟踪29个圆形标记点的位移,并且与电感式位移传感器测试结果的最大误差仅为5.6%。与传统的接触式位移测试方法相比,视觉测试方法具有布置迅速、成本低、测量精度高以及增加测量数量不会显著增加工作量等诸多优点,这使其成为一种替代传统位移测试的可靠且有效的方法。

关键词：液体火箭发动机双目视觉圆形标记点亚像素位移

共线反射式二次谐波实验中二阶非线性极化率的定量测定

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Chinese Journal of Chemical Physics 2024年第2期37卷 171-176,I0101页

作者：赵璇严力耕张文凯北京师范大学物理系应用光学北京市重点实验室北京100875

偏振二次谐波是一种广泛使用的对称性表征技术.然而,在共线反射式实验构型中,光路中必不可少的分束器会导致基频光和倍频光的偏振状态经透射或反射后发生改变,从而导致二次谐波信号的偏振态发生畸变,进而影响二阶非线性极化率的定量测... 详细信息

偏振二次谐波是一种广泛使用的对称性表征技术.然而,在共线反射式实验构型中,光路中必不可少的分束器会导致基频光和倍频光的偏振状态经透射或反射后发生改变,从而导致二次谐波信号的偏振态发生畸变,进而影响二阶非线性极化率的定量测定本文提出了一种基于菲涅尔系数的数据校正方法来解决这个问题,从而实现归一化二阶非线性极化率的定量测定,进一步通过理论模拟和实验证明了该方法的有效性和通用性.

关键词：二次谐波偏振态畸变分束器二阶非线性极化率

Self organizing optimization and phase transition in reinforcement learning minority game system

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Frontiers of physics 2024年第4期19卷 297-309页

作者： Si-Ping zhang Jia-Qi Dong Hui-Yu zhang Yi-Xuan Lü Jue Wang Zi-Gang Huang Key Laboratory of Biomedical Information Engineering of Ministry of Education Key Laboratory of Neuro-informatics&Rehabilitation Engineering of Ministry of Civil Affairsand Institute of Health and Rehabilitation ScienceSchool of Life Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China Lanzhou Center for Theoretical Physics and Key Laboratory of Theoretical Physics of Gansu Province Lanzhou UniversityLanzhou 730000China

Whether the complex game system composed of a large number of artificial intelligence(AI)agents empowered with reinforcement learning can produce extremely favorable collective behaviors just through the way of agent self-exploration is a matter of practical *** this paper,we address this question by combining the typical theoretical model of resource allocation system,the minority game model,with reinforcement *** individual participating in the game is set to have a certain degree of intelligence based on reinforcement learning *** particular,we demonstrate that as AI agents gradually becomes familiar with the unknown environment and tries to provide optimal actions to maximize payoff,the whole system continues to approach the optimal state under certain parameter combinations,herding is effectively suppressed by an oscillating collective behavior which is a self-organizing pattern without any external *** interesting phenomenon is that a first-order phase transition is revealed based on some numerical results in our multi-agents system with reinforcement *** order to further understand the dynamic behavior of agent learning,we define and analyze the conversion path of belief mode,and find that the self-organizing condensation of belief modes appeared for the given trial and error rates in the AI ***,we provide a detection method for period-two oscillation collective pattern emergence based on the Kullback–Leibler divergence and give the parameter position where the period-two appears.

关键词： oscillatory evolution collective behaviors phase transition reinforcement learning minority game

Ultra-broadband microwave absorber and high-performance pressure sensor based on aramid nanofiber,polypyrrole and nickel porous aerogel

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1912-1921页

作者： Leyi zhang Hongyu Jin Hanxin Liao Rao zhang Bochong Wang Jianyong Xiang Congpu Mu Kun Zhai Tianyu Xue Fusheng Wen State Key Laboratory of Metastable Materials Science&Technology Yanshan UniversityQinhuangdao 066004China Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China

Electronic devices have become ubiquitous in our daily lives,leading to a surge in the use of microwave absorbers and wearable sensor devices across various sectors.A prime example of this trend is the aramid nanofibers/polypyrrole/nickel(APN)aerogels,which serve dual roles as both microwave absorbers and pressure *** this work,we focused on the preparation of aramid nanofibers/polypyrrole(AP15)aerogels,where the mass ratio of aramid nanofibers to pyrrole was 1:*** employed the oxidative polymerization method for the preparation *** this,nickel was thermally evaporated onto the surface of the AP15 aerogels,resulting in the creation of an ultralight(9.35 mg·cm^(-3)).This aerogel exhibited a porous *** introduction of nickel into the aerogel aimed to enhance magnetic loss and adjust impedance matching,thereby improving electromagnetic wave absorption *** minimum reflection loss value achieved was-48.7 dB,and the maximum effective absorption bandwidth spanned 8.42 GHz with a thickness of 2.9 *** impressive metrics can be attributed to the three-dimensional network porous structure of the aerogel and perfect impedance ***,the use of aramid nanofibers and a three-dimensional hole structure endowed the APN aerogels with good insulation,flame-retardant properties,and compression *** under a compression strain of 50%,the aerogel maintained its resilience over 500 *** incorporation of polypyrrole and nickel particles further enhanced the conductivity of the ***,the final APN aerogel sensor demonstrated high sensitivity(10.78 kPa-1)and thermal *** conclusion,the APN aerogels hold significant promise as ultra-broadband microwave absorbers and pressure sensors.

关键词： porous aerogel aramid nanofibers microwave absorbers pressure sensor porous structure

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Carbon dots-incorporated CuSeO_(3)rationally regulates activity and selectivity of the hydrogen species via light-converted electrons

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Chinese Chemical Letters 2024年第1期35卷 332-337页

作者： Yuqi Ren Hongxu zhang Caihong Hao Qing Chang Ning Li Jinlong yang Shengliang Hu Research Group of New Energy Materials and Devices North University of ChinaTaiyuan 030051China State Key Laboratory of New Ceramics and Fine Processing Tsinghua UniversityBeijing 100084China

The chemoselective hydrogenation of structurally diverse nitroaromatics is a challenging ***,catalyst activity tends to decrease when excellent selectivity is *** here present a novel photocatalyst combining amino-functionalized carbon dots(N-CDs)with copper selenite nanoparticles(N-CDs@CuSeO_(3))for simultaneously improving selectivity and *** visible light irradiation,the prepared N-CDs@CuSeO_(3)exhibits 100%catalytic selectivity for the formation of 4-aminostyrene at full conversion of 4-nitrostyrene in aqueous solvent within a few *** excellent photocatalytic performance is mainly attributed to the precise control of the hydrogen species released from the ammonia borane by means of light-converted electrons upon N-CDs@CuSeO_(3).Besides,the defect states at the interface of N-CDs and CuSeO_(3)enable holes to be trapped for promoting separation and transfer of photogenerated charges,allowing more hydrogen species to participate in catalytic reaction.

关键词： Heterostructure Carbon dots Photocatalysis Chemoselective hydrogenation Copper selenite

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铜富集菖蒲生物炭对烟气汞去除性能及机制

中国环境科学 2024年第7期44卷 3646-3654页

作者：李鸿鹄安淼彭喜燕张敬东孙洋宋永伟中南财经政法大学信息工程学院环境与健康研究中心湖北武汉430073

以铜(Cu)污染修复植物石菖蒲生物质为原料,采用一步热解法制备了含铜位点的石菖蒲衍生生物碳(Cu-BC),用于去除烟气中的元素汞(Hg0).结果表明,500℃下热解的Cu-BC(Cu-BC500)在100℃反应温度下表现出良好的Hg0去除性能(约99%).通过比表面... 详细信息

以铜(Cu)污染修复植物石菖蒲生物质为原料,采用一步热解法制备了含铜位点的石菖蒲衍生生物碳(Cu-BC),用于去除烟气中的元素汞(Hg0).结果表明,500℃下热解的Cu-BC(Cu-BC500)在100℃反应温度下表现出良好的Hg0去除性能(约99%).通过比表面积测试法(BET)、X射线衍射(XRD)、扫描电镜(SEM)、X射线光谱(XPS)和傅里叶变换红外光谱(FT-IR)等表征分析表明,Cu-BC500具有相对较高的比表面积,丰富的含氧官能团和高度分散的Cu物种.XPS和汞程序升温脱附(Hg-TPD)分析表明,Cu-BC500所吸附的汞在生物炭样品的表面活性位点形成弱结合态汞Cu-O-Hg或铜汞合金.最后通过生命周期成本分析推算Cu-BC500的成本为3.50元/kg.与其他材料相比,Cu-BC500制备简单、成本较低,研究结果将为促进水体修复植物的资源化再利用以及燃煤电厂的汞减排提供新思路.

关键词：铜富集菖蒲废物利用生物炭烟气元素汞(Hg0)

Predicting Acute Mountain Sickness Using Regional Sea-Level Cerebral Blood Flow

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Biomedical and Environmental Sciences 2024年第8期37卷 887-896页

作者： Hao zhang Jie Feng Shiyu zhang Wenjia Liu Lin Ma Chinese PLA Medical School Beijing 100853China Department of Radiology First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

Objective To investigate the role of sea-level cerebral blood flow(CBF)in predicting acute mountain sickness(AMS)using three-dimensional pseudo-continuous arterial spin labeling(3D-pCASL).Methods Forty-eight healthy volunteers reached an altitude of 3,650 m by air after undergoing a head magnetic resonance imaging(MRI)including 3D-pCASL at sea *** CBF values of the bilateral anterior cerebral artery(ACA),middle cerebral artery(MCA),posterior cerebral artery(PCA),and posterior inferior cerebellar artery(PICA)territories and the laterality index(LI)of CBF were compared between the AMS and non-AMS *** analyses were performed to determine the relationship between CBF and AMS,and the predictive performance was assessed using receiver operating characteristic(ROC)*** The mean cortical CBF in women(81.65±2.69 mL/100 g/min)was higher than that in men(74.35±2.12 mL/100 g/min)(P<0.05).In men,the cortical CBF values in the bilateral ACA,PCA,PICA,and right MCA were higher in patients with AMS than in those *** CBF in the right PCA best predicted AMS(AUC=0.818).In women,the LI of CBF in the ACA was different between the AMS and non-AMS groups and predicted AMS with an AUC of *** Although the mechanism and prediction of AMS are quite complicated,higher cortical CBF at sea level,especially the CBF of the posterior circulatory system,may be used for prediction in male volunteers using non-invasive 3D-pCASL.

关键词： Acute mountain sickness High-altitude headache Cerebral blood flow Arterial spin labeling Magnetic resonance imaging

Structural phase transition in a new organic-inorganic hybrid post-perovskite:(N,N-dimethylpyrrolidinium)[Mn(N(CN)2)3]

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结构化学 2024年第6期43卷 40-44页

作者： Le Ye Wei-Xiong zhang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistryIGCMESun Yat-Sen UniversityGuangzhou510275China

In the realm of molecular phase transition research,particularly for applications in sensors,data storage and switching technologies,the role of organic-inorganic hybrid perovskite materials has been increasingly recog-nized for their significant ***,hybrid post-perovskites,as a critical subclass of perovskites,have not been thoroughly studied and mainly limit in the instances based on polyatomic bridging agents like dicyanamide(dca-)and non-cyclic organic ***,a polar cyclic quaternary ammonium cation,N,N-dimethylpyrrolidinium(DMP+),was used to assemble a new hybrid post-perovskite,(DMP)[Mn(dca)3](1),which undergoes a phase transition from orthorhombic Bmmb to monoclinic P21/n space group at 249 *** employing multiple techniques such as differential scanning calorimetry,variable-temperature single-crystal X-ray analysis,dielectric measurements,and Hirshfeld surface analysis,we disclosed the role of polar cyclic quaternary ammonium DMP+in elevating the phase-transition temperature by 48 K,generating significant dielectric switching effect and facilitating interlayer sliding of inorganic framework.

关键词： Structural phase transitions Dielectric switching Organic-inorganic hybrid crystals Post-perovskites