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Compressive near-field millimeter wave imaging algorithm based on Gini index and total variation mixed regularization

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Journal of Electronic Science and Technology 2023年第1期21卷 65-74页

作者： Jue Lyu Dong-Jie Bi Bo Liu Guo Yi xue-peng zheng Xi-Feng Li Li-Biao peng Yong-Le Xie Yi-Ming Zhang Ying-Li Bai School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu611731China Shanghai Spaceflight Precision Machinery Institute Shanghai201600China Electrical Engineering Department Northwestern UniversityEvanston60208USA Institute of Telecommunication Satellite China Academy of Space TechnologyBeijing100094China

A compressive near-field millimeter wave(MMW)imaging algorithm is *** the compressed sensing(CS)theory,the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-sampled sparse *** Gini index(GI)has been founded that it is the only sparsity measure that has all sparsity attributes that are called Robin Hood,Scaling,Rising Tide,Cloning,Bill Gates,and *** combining the total variation(TV)operator,the GI-TV mixed regularization introduced compressive near-field MMW imaging model is *** addition,the corresponding algorithm based on a primal-dual framework is also *** results demonstrate that the proposed GI-TV mixed regularization algorithm has superior convergence and stability performance compared with the widely used l1-TV mixed regularization algorithm.

关键词： Millimeter wave(MMW) Compressed sensing(CS) Gini index(GI) Total variation(TV) Signal processing Image reconstruction

Effect of HCV NS_3 protein on P53 protein expression in hepatocarcinogenesis

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World Journal of Gastroenterology 1999年第1期5卷 50-51页

作者： FENG De Yun, CHEN Rui xue, peng Yong, zheng Hui and YAN Ya Hui

AIM To investigate hepatocarcinogenesis by detecting the effect of HCV NS 3 protein on P53 protein expression in hepatocellular carcinoma (HCC) and pericarcinomatous liver tissue (PCLT). METHODS The expression of HCV NS 3 and P53 protein was detected with immunohistochemical technique (SP method) in specimens of HCC and PCLT from 47 patients with negative HBV. RESULTS The positive rate of HCV NS 3 protein was lower in HCC (62%) than in PCLT (83%) ( P 0 5), whereas their expression was closely related to PCLT ( P <0 01), and the expression rate of P53 protein in the cases of positive HCV NS 3 protein was higher than that in the cases of negative HCV NS 3 protein. CONCLUSION HCV NS 3 protein may exert its hepatocarcinogenic effect in early stage on host cells by endogenous pathway which may bring about mutation of p53 gene and transformation of hepatocytes.

关键词： liver neoplasms oncogenes hepatitis virus P53 protein

Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

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Journal of Energy Chemistry 2025年第1期100卷 730-738页

作者： peng zheng Wang Zhou Ying Mo Biao zheng Miaomiao Han Qin Zhong Wenwen Yang peng Gao Lezhi Yang Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology Hunan University Greater Bay Area Institute for Innovation Hunan University Changsha Research Institute of Mining & Metallurgy Co. LTD.

Hard carbon （HC） has been considered as promising anode material for sodium-ion batteries （SIBs）.The optimization of hard carbon’s microstructure and solid electrolyte interface （SEI） property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy （FTIR/EIS） and X-ray photoelectron spectroscopy （XPS） analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： X ray photoelectron spectroscopy

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong Li peng Ai Wanrong Guo Tuo zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu Sun Weichen zheng Liangwei Zhang Yanling xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

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低相噪超多频段VCO宽带锁相环的研究

微波学报 2016年第5期32卷 76-79,88页

作者：薛鹏郑欢孙恒青向冰中船重工集团第722研究所武汉430205 中船重工第七二二研究所低频电磁通信技术实验室武汉430205

为了解决宽带锁相环设计中相位噪声和输出频率范围的矛盾,分析并设计了一种基于超多频段压控振荡器(VCO)锁相环的方案。该方案通过降低VCO的频率灵敏度和每个VCO配置LC矩阵等效多个VCO的方法,使VCO在保证输出的频率范围的同时,优化了相... 详细信息

为了解决宽带锁相环设计中相位噪声和输出频率范围的矛盾,分析并设计了一种基于超多频段压控振荡器(VCO)锁相环的方案。该方案通过降低VCO的频率灵敏度和每个VCO配置LC矩阵等效多个VCO的方法,使VCO在保证输出的频率范围的同时,优化了相位噪声。实验结果发现,该方案可以使锁相环在保证较大的输出频率范围前提下拥有更低的相位噪声。

关键词：锁相环多频段压控振荡器相位噪声输出频率范围

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克氏针固定治疗开放性股骨髁间C3型骨折

医学信息（中旬刊） 2010年第12期5卷 3510-3511页

作者：彭学政张家界市人民医院骨科湖南张家界427000

股骨远端骨折据AO方法分类可分为关节外骨折（A型）、部分关节内骨折（B型）、完全关节内骨折（C型），12型中的c3型中髁部骨折粉碎明显，关节面骨折片呈蛋壳状，系高能量外伤造成多发伤，骨折处理难度大，处理时机受并发症的限制，致... 详细信息

股骨远端骨折据AO方法分类可分为关节外骨折（A型）、部分关节内骨折（B型）、完全关节内骨折（C型），12型中的c3型中髁部骨折粉碎明显，关节面骨折片呈蛋壳状，系高能量外伤造成多发伤，骨折处理难度大，处理时机受并发症的限制，致残率高，关节面骨折要求解剖复位，手术是改类骨折首选方法。若骨折开放，则合并骨关节感染可能性大，治疗难度显著增加。2004年8月至2009年5月采用彻底清创复位多根克氏针内固定治疗c3型中开放性髁部粉碎性骨折16例，疗效理想。

关键词：股骨髁间骨折开放性克氏针内固定

The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： Yanxi Li Jing xue Yuejia Ma Ke Ye xue Zhao Fangliang Ge Feifei zheng Lulu Liu Xu Gao Dayong Wang Qing Xia Department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical Sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for Genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation

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基于改进果蝇优化算法的无功优化

武汉大学学报（工学版） 2017年第4期50卷 560-565页

作者：冯云斌崔雪王恒彭政周斌武汉大学电气工程学院湖北武汉430072

将改进果蝇优化算法运用于无功优化领域,为电力系统的无功优化计算提供了一种新的算法.通过对迭代步长进行自适应调整可以有效避免果蝇算法可能陷入局部最优的问题,同时还能提高收敛精度.在无功优化模型中,对控制变量进行归一化处理,使... 详细信息

将改进果蝇优化算法运用于无功优化领域,为电力系统的无功优化计算提供了一种新的算法.通过对迭代步长进行自适应调整可以有效避免果蝇算法可能陷入局部最优的问题,同时还能提高收敛精度.在无功优化模型中,对控制变量进行归一化处理,使得量纲一致;将约束条件以罚函数的形式并入目标函数中,实现对状态变量的限制.以IEEE30节点系统和IEEE57节点系统为例,分别基于果蝇优化算法(FOA)、改进果蝇优化算法(IFOA)和遗传算法(GA)进行了无功优化计算,结果表明改进果蝇优化算法(IFOA)具有更好的优化效果和计算速度,更加接近全局最优值,采用该算法解决无功优化问题效果很好.

关键词：电力系统无功优化果蝇优化算法迭代步长自适应调整