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Science China Chemistry 2025年

作者： Guangli Xu hongda chen Xiaoming Wang State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences School of Chemistry and Materials Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

Dirhodium(II) complexes have achieved great success in organic synthesis,and fine-tuning their catalytic properties with various bridging ligands is well-investigated in carbene ***,combining dirhodium(II) with a sophisticated ligand as a catalyst in other reactions is still extremely challenging,especially for the asymmetric synthesis of valuable chiral ***,we report a dirhodium(II)/(S)-MeO-BIPHEP catalytic system for the challenging asymmetric β-alkenylation of α,β-unsaturated aldehydes,affording the corresponding chiral conjugate addition products in good yields with high enantioselectivities.A couple of drug-derived substrates were also compatible with the protocol,which has been successfully used to prepare biologically relevant pyranochromene *** mechanistic studies suggested that the dirhodium core might remain intact over the catalytic cycle,and the chiral diphosphine ligand plays a key role in this novel reactivity and determining the high enantioselectivities of the asymmetric conjugate addition.

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密码学与DoS碰撞攻击

微型计算机 2025年第4期 16-18页

作者：陈泓达成都理工大学计算机与网络安全学院四川成都610000

密码学技术在当今世界中扮演着至关重要的角色,它用于保护我们的通信和数据的安全性。然而,网络安全威胁的范围和复杂性也在不断增加。其中一种威胁是拒绝服务(DoS)攻击,文章将讨论DoS碰撞攻击的概念和原理,以及攻击者的动机和目标。对... 详细信息

密码学技术在当今世界中扮演着至关重要的角色,它用于保护我们的通信和数据的安全性。然而,网络安全威胁的范围和复杂性也在不断增加。其中一种威胁是拒绝服务(DoS)攻击,文章将讨论DoS碰撞攻击的概念和原理,以及攻击者的动机和目标。对现有的一些范例与应用进行综述。最后,我们会总结当前的研究进展,文章旨在为网络安全领域的研究者提供一个新视角,以应对不断进化的DoS碰撞攻击威胁,并探索其未来的防御方向。

关键词：密码学 DoS攻击

Colorectal Cancer Screening in China:Status,Challenges,and Prospects——China,2022

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China CDC weekly 2022年第15期4卷 322-328页

作者： hongda chen Bin Lu Min Dai Medical Research Center Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Colorectal cancer(CRC)ranks third among the most commonly diagnosed cancers in *** proof that screening can decrease CRC incidence and mortality,there are still gaps remaining between CRC screening objectives and reality in *** this review,we provided an overview of the status of CRC screening in ***,we summarized the current CRC screening programs and strategies in ***,we reviewed the authoritative CRC screening and early detection guidelines in China to orient future evidence-based guideline ***,we identified current challenges and further provided some suggestions to improve the implementation of CRC screening *** maximize the effectiveness of CRC screening,further research on risk prediction models including polygenic risk scores and prior screening outcomes,novel biomarkers and artificial intelligence,and personalized screening strategies are *** cohort study and microsimulation techniques are recommended for long-term evaluations of the effectiveness of CRC screening strategies.

关键词： summarized spite screening

A low-complexity ECG processing algorithm based on the Haar wavelet transform for portable health-care devices

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Science China(Information Sciences) 2014年第12期57卷 132-145页

作者： LI Peng LIU Ming ZHANG Xu chen hongda State Key Laboratory on Integrated Optoelectronic Institute of Semiconductors Chinese Academy of Science

This paper presents a simple Electrocardiogram(ECG)processing algorithm for portable healthcare *** algorithm consists of the Haar wavelet transform(HWT),the modulus maxima pair detection(MMPD)and the peak position modification(PPM).To lessen the computational complexity,a novel no multiplier structure is introduced to implement *** the MMPD,the HWT coefficient at scale 24is processed to find candidate peak positions of *** PPM is designed to correct the time shift in digital process and accurately determine the location of *** new methods are proposed to improve anti-jamming performance in MMPD and *** by the MIT-BIH arrhythmia database,the sensitivity(Se)of QRS detection is 99.53%and the positive prediction(Pr)of QRS detection is 99.70%.The QT database is chosen to fully validate this algorithm in complete delineation of ECG *** meanμand standard deviationσbetween test results and annotations are *** ofσsatisfies the CSE limits which indicates that the results are stable and reliable.A detailed and rigorous computational complexity analysis is presented in this *** number of arithmetic operations in N input samples is chosen as the criterion of *** any multiplication operations,the number of addition operations is only about *** algorithm achieves high detection accuracy and the lower computational complexity.

关键词： Haar wavelet transform(HWT) modulus maxima pair detection(MMPD) peak position modification(PPM) ECG processing low complexity portable health-care devices

A novel approach framework based on statistics for reconstruction and heartrate estimation from PPG with heavy motion artifacts

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Science China(Information Sciences) 2018年第2期61卷 182-193页

作者： Bo PANG Ming LIU Xu ZHANG Peng LI hongda chen State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences University of Chinese Academy of Sciences

One of the most important applications of photoplethysmography(PPG) signal is heartrate(HR)estimation. For its applications in wearable devices, motion artifact(MA) may be the most serious challenge for randomness both in format and temporal distribution. This paper proposes an advanced time-frequency analysis framework based on empirical mode decomposition(EMD) to select specific time slices for signal reconstruction. This framework operates with a type of pre-processing called variance characterization series(VCS), EMD, singular value decomposition(SVD), and a precise and adaptive 2-D filtration reported *** filtration is based on Harr wavelet transform(HWT) and 3 rd order cumulant analysis, to make it have resolution in both the time domain and different components. The simulation results show that the proposed method gains 1.07 in absolute average error(AAE) and 1.87 in standard deviation(SD); AAEs’ 1 st and 3 rd quartiles are 0.12 and 1.41, respectively. This framework is tested by the Physio Bank MIMIC II waveform database.

关键词： photoplethysmography(PPG) motion artifact empirical mode decomposition(EMD) singular value decomposition discrete wavelet transform higher-order statistics

Transductive Transfer Dictionary Learning Algorithm for Remote Sensing Image Classification

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2267-2283页

作者： Jiaqun Zhu hongda chen Yiqing Fan Tongguang Ni Aliyun School of Big Data Changzhou UniversityChangzhou213164China Hua Lookeng Honors College Changzhou UniversityChangzhou213164China

To create a green and healthy living environment,people have put forward higher requirements for the refined management of ecological resources.A variety of technologies,including satellite remote sensing,Internet of Things,artificial intelligence,and big data,can build a smart environmental monitoring *** sensing image classification is an important research content in ecological environmental *** sensing images contain rich spatial information andmulti-temporal information,but also bring challenges such as difficulty in obtaining classification labels and low classification *** solve this problem,this study develops a transductive transfer dictionary learning(TTDL)*** the TTDL,the source and target domains are transformed fromthe original sample space to a common *** trains a shared discriminative dictionary in this subspace,establishes associations between domains,and also obtains sparse representations of source and target domain *** obtain an effective shared discriminative dictionary,triple-induced ordinal locality preserving term,Fisher discriminant term,and graph Laplacian regularization termare introduced into the *** triplet-induced ordinal locality preserving term on sub-space projection preserves the local structure of data in low-dimensional *** Fisher discriminant term on dictionary improves differences among different sub-dictionaries through intra-class and inter-class *** graph Laplacian regularization term on sparse representation maintains the manifold structure using a semi-supervised weight graphmatrix,which can indirectly improve the discriminative performance of the *** TTDL is tested on several remote sensing image datasets and has strong discrimination classification performance.

关键词： Classification dictionary learning remote sensing image transductive transfer learning

CXCR4 Peptide Conjugated Au-Fe2O3 Nanoparticles for Tumor-targeting Magnetic Resonance Imaging

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Chemical Research in Chinese Universities 2018年第4期34卷 584-589页

作者： LIU Guifeng chen hongda YU Shaonan LI Xiaodong WANG Zhenxin Department of Radiology China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China State Key Laboratory of Eleetroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Aeademy of Sciences Changehun 130022 P R. China Department of Radiology the First Hospital of Jilin University Changchun 130021 P. R. China

Peptide-functionalized Au-Fe2O3 nanoparticles（termed as anti-CXCR4-Au-Fe2O3 NPs） have been constructed through conjugation of dumbbell-like Au-Fe203 NPs with C-X-C motif chemokine receptor 4（CXCR4） binding cyclic peptide. One dumbbelMike Au-Fe2O3NP composes an Au NP[（3.3±0.3） nm in diameter] for conjugating CXCR4 binding cyclic peptide through Au-S covalent bond and a Fe2O3 NP[（8.7±0.8） nm in diameter] for using as T2-weighted magnetic resonance imaging（MRI） contrast agent. The anti-CXCR4-Au-Fe2O3 NPs have reasonable biocompatibility and integration of T2-weighted MRI contrast and tumor-targeting functionalities. The anti- CXCR4-Au-Fe2O3 NPs exhibit strong interactions with two kinds of breast tumor cells, MCF-7 cells and MDA-MB-231 cells, and high negative contrast in MRI of MDA-MB-231 tumor bearing mouse with 62% decreasing of MRI signal, indicating that the anti-CXCR4-Au-Fe2O3 NPs can recognize tumor with high efficacy and specificity.

关键词： Dumbbell-like Au-Fe2O3 nanoparticle C-X-C motif chemokine receptor 4 Cyclic peptide T2-Weighted magnetic resonance imaging Tumor targeting ability

Fabrication of strongly adherent platinum black coatings on microelectrodes array

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Science China(Information Sciences) 2014年第4期57卷 208-217页

作者： TANG RongYu PEI WeiHua chen SanYuan ZHAO Hui chen YuanFang HAN Yao WANG ChunLan chen hongda State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of Sciences State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of Sciences Beijing 100083 China Department of Tissue Engineering Institute of Basic Medical Sciences and Tissue Engineering Research CenterAcademy of Military Medical Sciences

Platinum black coating can effectively improve the performance of MEAs(microelectrodes array)in neural signal transduction,though its lack of adhesion strength and durability tampers its usage in long term *** a new method of composite electrodeposition provides highly adhesive platinum black coating that enables MEAs for a month’s long task and repeatable *** new method was compared with present techniques on multiple aspects,*** surface area,surface morphology,interfacial impedance,durability and real application *** show that the new composite coating provides greatly improved durability without compromising its *** cells were cultured on these MEAs for 40 days in vitro and spontaneous action potentials with high signal/noise ratio were *** model and simulation provided preliminary understanding on the mechanism of this strengthened platinum black coating.

关键词： microelectrode array platinum black electroplating electrophysiology neural culture

A composite insulation structure for silicon-based planar neuroprobes

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Science China(Technological Sciences) 2012年第9期55卷 2436-2440页

作者： ZHAO Hui PEI WeiHua chen SanYuan GUI Qiang TANG RongYu GUO Kai chen hongda State Key Laboratory Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

Silicon-based planar neuroprobes are composed of silicon substrate,conducting layer,and insulation layers of SiO 2 or SiN *** insulation layer is very important because it affects many key parameters of neuprobes,like impedance,SNR(signal noise ratio),reliability,*** membrane of SiO 2 or SiN are not good choices for insulation layer,since defects and residual stress in these layers can induce bad *** this paper a composite insulation structure is studied,with thermal SiO 2 as the lower insulation layer and with multilayer membrane composed of PECVD SiO 2 and SiN as the upper insulation *** structure not only solves the problem of residual stress but also ensures a good probe *** it's a good choice for insulation layer of neuroprobes.

关键词： silicon-based neuroprobes insulation structure multilayer membrane stress durability passivation

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A compact neural recording interface based on silicon microelectrode

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Science China(Technological Sciences) 2013年第11期56卷 2808-2813页

作者： HAN JianQiang ZHANG Xu PEI WeiHua GUI Qiang LIU Ming chen hongda State Key Laboratory on Integrated Optoelectronic Institute of SemiconductorsChinese Academy of Sciences

A prototype of hybrid neural recording interface has been developed for extracellular neural recording. It consists of a silicon-based plane microelectrode array and a CMOS low noise neural amplifier chip. The neural amplifier chip is designed and implemented in 0.18 μm N-well CMOS 1P6M technology. The area of the neural preamplifier is only 0.042 mm2 with a gain of 48.3 dB. The input equivalent noise is 4.73 btVrms within pass bands of 4 kHz. To avoid cable tethering for high dense mul- tichannel neural recording interface and make it compact, flip-chip bonding is used to integrate the preamplifier chip and the microelectrode together. The hybrid device measures 3 mm×5.5 mm×330μm, which is convenient for implant or in-vivo neu- ral recording. The hybrid device was testified in in-vivo experiment. Neural signals were recorded from hippocampus region of anesthetized Sprague Dawley rats successfully.

关键词： neural recording interface silicon microelectrode CMOS preamplifier flip-chip bonding hybrid device

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