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The optimal retrieval of ocean color constituent concentrations based on the variational method

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Journal of Hydrodynamics 2013年第1期25卷 62-71页

作者： YU Hong FAN Zhe du hua-dong College of Meteorology and Oceanography PLA University of Science and Technology Meteorological Center of Air Force Command in Nanjing Military Region

In this paper, a new approach to the optimal retrieval of the ocean color based on the variational method is developed by setting up a rational target functional combining with the Broydor Fletcher, Goldfarb, Shanno （BFGS） optimal algorithm. The numerical tests and the exemplary retrievals are carried out and compared with the statistical retrievals and the optimal retrievals based on the genetic algorithm. The results show that this approach enjoys a higher accuracy as compared to the statistical method and a higher efficiency as compared to the genetic algorithm. The optimal retrieval method presented in this paper provides a new idea for the ocean color inversion and could also be used as a reference for the direct assimilation of the satellite data into the ecological models.

关键词： ocean color optimal retrieval variational method Broydor Fletcher Goldfarb Shanno (BFGS) algorithm

Gut microbiota-astrocyte axis: new insights into age-related cognitive decline

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Neural Regeneration Research 2025年第4期20卷 990-1008页

作者： Lan Zhang Jingge Wei Xilei Liu Dai Li Xiaoqi Pang Fanglian Chen Hailong Cao ping Lei Haihe Laboratory of Cell Ecosystem Department of GeriatricsTianjin Medical University General HospitalTianjinChina Tianjin Geriatrics Institute Tianjin Medical University General HospitalTianjinChina Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalNational Key Clinical SpecialtyTianjin Institute of Digestive DiseasesTianjin Key Laboratory of Digestive DiseasesTianjinChina Department of Urology Tianjin Medical University General HospitalTianjinChina Tianjin Neurological Institution Tianjin Medical University General HospitalTianjinChina

With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent *** is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of *** microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive *** article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative *** article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial ***,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s *** findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition.

关键词： age aging Alzheimer’s disease astrocytes cognitive decline dementia gut microbiota gut–brain axis microbial metabolites neuroinflammation Parkinson’s disease

MeshCNN-based BREP to CSG conversion algorithm for 3D CAD models and its application

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Nuclear Science and Techniques 2022年第6期33卷 75-88页

作者： Yue-Tong Luo hua du Yi-Man Yan Hefei University of Technology Hefei 230009China University of Science and Technology of China Hefei 230027China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China State Power Investment Corporation Research Institute National Energy Key Laboratory of Nuclear Power SoftwareBeijing 102209China

In the field of neutronics analysis, it is imperative to develop computer-aided modeling technology for Monte Carlo codes to address the increasing complexity of reactor core components by converting 3D CAD model(boundary representation, BREP) to MC model(constructive solid geometry, CSG). Separation-based conversion from BREP to CSG is widely used in computer-aided modeling MC codes because of its high efficiency, reliability, and easy implementation. However, the current separation-based BREP-CSG conversion is poor for processing complex CAD models, and it is necessary to divide a complex model into several simple models before applying the separation-based conversion algorithm, which is time-consuming and tedious. To avoid manual segmentation, this study proposed a MeshCNN-based 3D-shape segmentation algorithm to automatically separate a complex model. The proposed 3D-shape segmentation algorithm was combined with separation-based BREP-CSG conversion algorithms to directly convert complex *** proposed algorithm was integrated into the computeraided modeling software cosVMPT and validated using the Chinese fusion engineering testing reactor model. The results demonstrate that the MeshCNN-based BREP-CSG conversion algorithm has a better performance and higher efficiency, particularly in terms of CPU time, and the conversion result is more intuitive and consistent with the intention of the modeler.

关键词： BREP to CSG conversion Computer-aided modeling cosVMPT Intelligent pre-segmentation MeshCNN

Peptidase Activities of Tripeptidyl Peptidase Ⅰ (TPP Ⅰ): Exopeptidase and Endopeptidase

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Chemical Research in Chinese Universities 2006年第1期22卷 65-67页

作者： du Pei-ge AN Li-ping QIU Fang-ping LU Gang Clinical Diagnosis Laboratory of Beihua University Jilin 132013 P. R. China College of Biological Engineering Changchun University of Technology Changchun 130012 P. R. China

The defect of TPP Ⅰ causes a disease, late infantile neuronal ceroid lipofuscinosis（LINCL, CLN2）. To investigate the bio-activity of tripeptidyl peptidase Ⅰ （TPP Ⅰ ） from rat kidneys, the effects of digestion of angiotensin Ⅱ （Ang Ⅱ ） and a synthetic endo-type substrate（ Gly^1-Lys-Pro^5-lie-Pro^5-Phe-Phe-Arg-Leu-Lys^10） via TPP I were ana- lyzed by HPLC and TOF-MS. The data suggest that the degradation rate of Ang I1 can reach 18. 2% by the rat TPP I and DRV（Asp-Arg-Val） can be released from N-termini of Ang Ⅱ within 16 h. In addition, the synthetic endotype substrate is cleaved at the same position between Phe6 and Phe^7. Accordingly, TPP Ⅰ shows two kinds of peptidase activities. One is a tripeptidyl peptidase activity and the other is a pepstatin insensitive carboxyl endopeptidase activity. Tripeptidyl peptidase activity and pepstatin insensitive carboxyl endopeptidase activity seem to be dual phases of one enzyme, TPP Ⅰ.

关键词： Rat TPP Ⅰ Angiotensin Ⅱ Endo-type substrate Endopeptidase activity

Preparation and Characterization of Cyano-Silicon-Containing Arylacetylene Resins and Their Composites:dual Enhancement Strategy Involving Physical Interfacial Interactions and Chemical Crosslinking

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Chinese Journal of Polymer Science 2024年第11期42卷 1719-1729,I0009页

作者： Chao-En Jin hua-Mei Zhu Lei Wang Fan Wang Ya-ping Zhu Shi-Feng Deng Hui-Min Qi Lei du Key Laboratory of Specially Functional Polymeric Materials and Related Technology of Ministry of Education School of Materials Science and EngineeringEast China University of Science&TechnologyShanghai200237China

Silicon-containing arylacetylene (PSA) resins have broad application prospects because of their excellent heat ***,improving their mechanical properties and interfacial bonding with reinforcement fibers while maintaining heat resistance is a challenge in engineering ***,poly(diethynylbenzene-methylsilyl-3-benzonitrile)(DEB-CN) and poly(diethynylbenzene-methylsilyl-3,6-diethynylcarbazole-3-benzonitrile)(DEC-CN) were synthesized via an isopropylmagnesium chloride lithium-chloride complex (i-PrMgCl·LiCl),overcoming the compatibility problem between cyano groups and Grignard *** cyano and alkyne groups in the resin underwent cyclization to form pyridine,catalyzed by the-NH-moiety in DEC-CN,resulting in extremely high thermal stability (5%weight loss temperature:669.3°C,glass transition temperature>650°C).The combination of cyano dipole-dipole pairing and hydrogen bonding greatly enhanced the resin-fiber interface properties,while the generated pyridine promoted stress relief in the crosslinked network,substantially improving the mechanical properties of the cyano-silicon-containing arylacetylene resin *** flexural strength of quartz fiber cloth/DEC-CN composites was 298.2 MPa at room temperature and 145.9 MPa at 500°C,corresponding to 84.0%and 127.6%enhancements,respectively,over the cyano-free *** cyano-silicon-containing arylacetylene resins exhibited a dual reinforcement mechanism involving physical interfacial interactions and chemical crosslinking,achieving a good balance between thermal stability and mechanical properties.

关键词： Silicon-containing arylacetylene resins Cyano group Heat resistance Composite interfaces Mechanical properties

The low-latitude sodium layer:comparative data from lidar observations at Hainan,China and São Paulo,Brazil

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Earth and Planetary Physics 2025年第1期9卷 39-53页

作者： Fang Wu Jing Jiao GuoTao Yang LiFang du ZhengKuan Liu HaoRan Zheng JiXin Guo Shaohua Gong YaJun Zhu State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Hainan National Field Science Observation and Research Observatory for Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China China-Brazil Joint Laboratory for Space Weather NSSC/INPESão Josédos Campos 12227-010Brazil School of Physics and Electronics Engineering Hainan Normal UniversityHaikou 571158China

Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude *** sodium detected by lidar can yield clues to dynamic and chemical processes in these spatial layers above the Earth’s *** paper is based on sodium layer data collected at two low-latitude stations,one in the northern hemisphere and one in the *** low-latitude sodium layer exhibits conspicuous seasonal variations in shape,density,and altitude;these variations are similar between Earth’s hemispheres:sodium layer density at both stations reaches its seasonal maximum in autumn and minimum in ***,maximal Na density over Brazil is greater than that over *** variations of Na density above the two low-latitude stations are also similar;at both,maxima are observed before *** variations of the Na layer over Brazil that differ from those observed in the northern hemisphere may be related to the South Atlantic Magnetic Anomaly(SAMA)or fountain *** suggest that low-latitude Na layer data may provide useful additional evidence that could significantly improve the low-latitude part of the WACCM-Na model.

关键词： metallic sodium layer seasonal variation nocturnal variation lidar

Periodic Solution to BAM-type Cohen-Grossberg Neural Network with Time-varying Delays

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 427-442页

作者： An-ping Chen Qun-hua Gu Department of Mathematics Xiangnan University Chenzhou Hunan 423000 China School of Mathematics and Computational Science Xiangtan University Xiangtan Hunan 411005 China

By using the continuation theorem of Mawhin＇s coincidence degree theory and the Liapunov func tional method, some sufficient conditions are obtained to ensure the existence, uniqueness and the global exponential stab... 详细信息

关键词： periodic solution time-varying delays global exponential stability BAM-type Cohen-Grossberg neural network coincidence degree theory

The FENE dumbbell Model near Equilibrium

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Acta Mathematica Sinica,English Series 2008年第4期24卷 529-538页

作者： Fang hua LIN ping ZHANG Courant Institute New York University New York NY 10012 USA Academy of Mathematics & Systems Science CAS Beijing 100080 P. R. China

We study the global existence of smooth solutions near the equilibrium to a coupled microscopic-macroscopic FENE dumbbell model which arises from the kinetic theory of diluted solutions of polymeric liquids with nonin... 详细信息

关键词： FENE dumbbell model polymeric liquids Navier-Stokes equations Fokker-Planck equations

Simple intra-signal-interference removing detector for HE-DCSK

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The Journal of China Universities of Posts and Telecommunications 2013年第6期20卷 102-108页

作者： YANG hua JIANG Guo-ping College of Electronic Science and Engineering Nanjing University of Posts and Telecommunications College of Automation Nanjing University of Posts and Telecommunications

In this paper, a novel simple detector is designed to remove the intra-signal interference in high efficiency differential chaos shift keying （HE-DCSK） modulation scheme. With the help of data bit estimated before correlation detection, this new detector could remove the modulated chaotic segment that would form intra-signal interference component in the correlator output from every received information-bearing signal in HE-DCSK, leading to greatly and effectively improved system bit error rate （BER） performance. The effectiveness of this proposed detector is studied analytically based on the numerical integration method and evaluated by computer simulation in additive-white-Gaussian- noise （AWGN） channel. Simulation results reveal that the proposed detector can dramatically improve the overall BER performance of HE-DCSK even at relatively low signal noise ratio （SNR） levels.

关键词： chaos communications intra-signal interference removing high-efficiency differential chaos shift keying bit error rate