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构造两个曲面的拼接曲面

工程图学学报 2005年第1期26卷 39-44页

作者：程进三高小山中国科学院数学与系统科学研究院数学机械化重点实验室北京100080

给出了当两个待拼接曲面的拼接线具有参数化形式或者可以参数化时,它们之间 G1光滑拼接曲面的构造方法。所得的拼接曲面是由一个空间曲线集定义的,每一条空间曲线由拼接线上的点对确定。并且拼接曲面都是参数曲面,它们的形状可以通过预... 详细信息

给出了当两个待拼接曲面的拼接线具有参数化形式或者可以参数化时,它们之间 G1光滑拼接曲面的构造方法。所得的拼接曲面是由一个空间曲线集定义的,每一条空间曲线由拼接线上的点对确定。并且拼接曲面都是参数曲面,它们的形状可以通过预设的参数很好地调整和控制。作为实例,讨论了两个截口是平面的或非平面的(由两个二次曲面定义)的二次曲面之间的拼接曲面的构造和一般的参数曲面的拼接曲面的构造。

关键词：计算机应用曲面拼接参数曲面 Bezier曲线

Ultra-broadband and wide-angle reflective terahertz polarization conversion metasurface based on topological optimization

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Chinese Physics B 2024年第10期33卷 287-294页

作者： Ya-Jie Zhang Chao-Long Li Jia-Qi Luan Ming Zhao Ding-shan gao Pei-Li Li Faculty of Electrical and Optical Engineering Nanjing University of Posts and CommunicationsNanjing 210023China Wuhan National Laboratory for Optoelectronics and School of Physics Huazhong University of Science and TechnologyWuhan 430074China

Terahertz polarization conversion devices have significant potential applications in various fields such as terahertzimaging and *** this paper,we utilize genetic algorithms to topologically optimize the metasurface unit cellsand design a reflective linear polarization conversion metasurface with ultra-broadband and wide-angle *** partitioning the metallic pattern layer into quadrants,the encoding length is effectively reduced,resulting in a shorteroptimization *** research results indicate that the converter possesses a polarization conversion efficiency ratio higherthan 90%and a relative bandwidth ratio of 125%in a range of 0.231-0.995 ***,it can maintain excellentpolarization conversion properties when the incident angle of terahertz waves is less than 45°and the polarization angle isless than 15°,demonstrating excellent *** insights are provided for the design of terahertz wide-angle ultrawidebandpolarization conversion devices,and the proposed metasurfce has potential applications in terahertz polarizationimaging,spectroscopy and communication fields.

关键词： metasurface polarization conversion topology optimization ultra-broadband

The dysfunctional Wnt pathway down-regulates MLH1/SET expression and promotes microsatellite instability and immunotherapy response in colorectal cancer

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Genes & Diseases 2024年第2期11卷 542-545页

作者： Jiyan Wang Tao He Qingle gao Hongkai Chang Xintong Dai Juze Yang Shuangping Liu Shuai Zhang Changliang shan Chunze Zhang State Key Laboratory of Medicinal Chemical Biology College of Pharmacy and Tianjin Key Laboratory of Molecular Drug ResearchNankai UniversityTianjin 300350China Departments of Pathology Characteristic Medical Center of The Chinese People's Armed Police ForceTianjin 300162China Department of Respiratory Medicine Sir Run Run Shaw Hospital and Institute of Translational MedicineZhejiang University School of MedicineHangzhouZhejiang 310016China Department of Pathology Medical SchoolDalian UniversityDalianLiaoning 116622China School of Integrative Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Colorectal Surgery Tianjin Union Medical CenterNankai UniversityTianjin 300121China

The tumor heterogeneity results in different clinical characteristics of tumor patients,so precise therapy is a popular treatment strategy *** instability(MSI)is found in 10%-15%of colorectal cancer(CRC)patients and exhibits different clinical outcomes than microsatellite stable(MSS)***,MSI patients have a better prognosis than patients with stable *** patients exhibit clinical features that are not responsive to chemotherapy,however,Msl patients showed excellent responses to immunotherapy.'Although the subtype classification of MSI is beneficial to the clinical treatment of CRC patients,the mechanism of MSl remains unclear.

关键词： immunotherapy colorectal clinical

浅谈食品中碳水化合物在加热处理中的几种变化

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食品科技 2000年第1期25卷 61-62,63页

作者：高晓杉魏力军辽宁抚顺市产品质量监督检验所 113006

论述了食品中碳水化合物在加热处理中的四种变化包括糊化、老化、美拉德反应和焦糖化以及这些变化发生的机理，同时介绍了影响老化和美拉德反应的一些因素。

关键词：食品加热碳水化合物糊化老化焦糖化

Differentiation and immunosuppressive function of CD19^(+)CD24^(hi)CD27^(+) regulatory B cells are regulated through the miR-29a-3p/NFAT5 pathway

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 472-480页

作者： Jin-Yang Li Tian-Shuo Feng Ji gao Xin-Xiang Yang Xiang-Cheng Li Zhen-Hua Deng Yong-Xiang Xia Zheng-shan Wu Hepatobiliary Center the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Key Laboratory of Liver Transplantation Chinese Academy of Medical SciencesNanjing 210029China NHC Key Laboratory of Living Donor Liver Transplantation Nanjing Medical UniversityNanjing 210029China

Background: Regulatory B cells(Bregs) is an indispensable element in inducing immune tolerance after liver transplantation. As one of the microRNAs(miRNAs), mi R-29a-3p also inhibits translation by degrading the target mRNA, and yet the relationship between Bregs and mi R-29a-3p has not yet been fully explored. This study aimed to investigate the impact of miR-29a-3p on the regulation of differentiation and immunosuppressive functions of memory Bregs(m Bregs) and ultimately provide potentially effective therapies in inducing immune tolerance after liver transplantation. Methods: Flow cytometry was employed to determine the levels of Bregs in peripheral blood mononuclear cells. TaqMan low-density array miRNA assays were used to identify the expression of different miRNAs, electroporation transfection was used to induce mi R-29a-3p overexpression and knockdown, and dual luciferase reporter assay was used to verify the target gene of miR-29a-3p. Results: In patients experiencing acute rejection after liver transplantation, the proportions and immunosuppressive function of m Bregs in the circulating blood were significantly impaired. mi R-29a-3p was found to be a regulator of m Bregs differentiation. Inhibition of miR-29a-3p, which targeted nuclear factor of activated T cells 5(NFAT5), resulted in a conspicuous boost in the differentiation and immunosuppressive function of m Bregs. The inhibition of mi R-29a-3p in CD19~+ B cells was capable of raising the expression levels of NFAT5, thereby promoting B cells to differentiate into m Bregs. In addition, the observed enhancement of differentiation and immunosuppressive function of m Bregs upon mi R-29a-3p inhibition was abolished by the knockdown of NFAT5 in B cells. Conclusions: mi R-29a-3p was found to be a crucial regulator for m Bregs differentiation and immunosuppressive function. Silencing mi R-29a-3p could be a potentially effective therapeutic strategy for inducing immune tolerance after liver transplantation.

关键词： Regulatory B cells miR-29a-3p NFAT5 Liver transplantation

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函数分解问题的判定性研究

系统科学与数学 2012年第8期32卷 928-934页

作者：赵尚威童朝旭高小山中央民族大学理学院北京100070 康奈尔大学运筹系纽约州14853 中国科学院数学与系统科学研究院北京100190

函数分解问题是一个重要的数学问题,它被应用于多变量公钥密码系统的设计中.作者主要关注函数分解问题的判定性问题,将整系数多变元多项式方程求解问题与函数分解问题建立起了一定的联系,从而利用著名的希尔伯特第十问题的不可判定性来... 详细信息

函数分解问题是一个重要的数学问题,它被应用于多变量公钥密码系统的设计中.作者主要关注函数分解问题的判定性问题,将整系数多变元多项式方程求解问题与函数分解问题建立起了一定的联系,从而利用著名的希尔伯特第十问题的不可判定性来对函数分解问题的判定性问题进行研究.

关键词：函数分解问题希尔伯特第十问题不可判定性

A synthesis of the Cretaceous wildfire record related to atmospheric oxygen levels?

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Journal of Palaeogeography 2024年第1期13卷 149-164页

作者： Da-Wei Lü Wen-Xu Du Zhi-Hui Zhang Yuan gao Tian-Tian Wang Jin-Cheng Xu Ao-Cong Zhang Cheng-shan Wang shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina School of Earth Sciences and Resources China University of GeosciencesBejing 100083China Institute of Earth Sciences China University of Geosciences(Bejing)Beijing 100083China

The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the Late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.

关键词： Wildfire Cretaceous Atmospheric oxygen Taphonomy Charcoal

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CNC固有误差估计新方法

系统科学与数学 2012年第8期32卷 1033-1044页

作者：郭建新张可高小山中国科学院系统科学研究所数学机械化实验室北京100190

提出了一个估计数控机床固有误差的新方法.与已有利用动态最小二乘(MLS)的方法相比,采用径向基函数(RBF)直接对已有数据进行拟合估计,大大提高了计算效率.还观察到,RBF方法在某个采样半径下误差估计精度总是优于MLS方法,而大于这个采样... 详细信息

提出了一个估计数控机床固有误差的新方法.与已有利用动态最小二乘(MLS)的方法相比,采用径向基函数(RBF)直接对已有数据进行拟合估计,大大提高了计算效率.还观察到,RBF方法在某个采样半径下误差估计精度总是优于MLS方法,而大于这个采样半径后则MLS方法较好.由此提出了穿越半径的概念与一种基于RBF方法与MLS方法的混合方法,以得到更好的误差估计.实验结果证实了新方法的有效性.

关键词：数控机床误差估计移动最小二乘核方法 MLS可信度

W-band CMOS beamforming ICs and integrated phased-array antennas with 20+ Gb/s data rates

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Science China(Information Sciences) 2024年第11期67卷 300-316页

作者： Dixian ZHAO Peigen YU shan JIANG Weihan gao Pingyang HE Huiqi LIU School of Information Science and Engineering Southeast University Purple Mountain Laboratories Chengdu Xphased Technology Co. Ltd.

This article presents the design and implementation of W-band transmitter(TX) and receiver(RX) phased-array antennas, which leverage CMOS and printed circuit board(PCB) technologies to integrate the phased-array antennas with eight-channel beamforming ICs. The beamforming IC applies the variable gain amplifier(VGA) with fractional bits and the vector-modulated variable gain phase shifter(VGPS) for wide range and high precision of gain and phase shifting, providing moderate power gain. The phased-array board consists of 384 TX and 384 RX antenna elements, along with 48 TX and 48 RX beamforming *** also incorporates Wilkinson power dividers/combiners, a power management system, and a beamforming control module, all integrated into a cost-effective multi-layer PCB. Fabricated in 65-nm bulk CMOS, the IC achieves 3° RMS phase error for phase shifting and 0.5 d B RMS gain error for gain shifting, ensuring high precision of antenna pointing. The over-the-air(OTA) measurement of the proposed W-band phased-array antennas achieves a 64-QAM constellation with a symbol rate of 3.5 GS/s, resulting in raw data rates of21 Gb/s.

关键词： W-band phased array CMOS Gigabit wireless link antenna on PCB

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