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The Journal of China Universities of Posts and Telecommunications 2002年第1期9卷 30-34页

作者： LUOTao haojian-jun 等 TelecommunicationEngineeringSchool BeijingUniversityofPostsandTelecommunicationsBeijing100876P.R.China TelecommunicationEngineeringSchool BeijingUniversityofPostsandTelecommunicationsBeijing100876

Based on the studies of Reed-Solomon codes and orthogonalspace-time block codes over Rayleigh fading channel, a theoreticalmethod for estimating performance of Reed-Solomon codes concatenatedwith orthogonal space- time block codes is presented in this *** an upper bound of the bit error rate is also obtained. It isshown through computer simulations that the signal-to-noise ratioreduces about 15 dB or more after orthogonal space-time block codesare concatenate with Reed-Solomon(15,6)codes over Rayleigh fadingchannel, when the bit error rate is 10^-4.

关键词： channel codes space-time codes concatenated codes diversity technology

Performance Analysis of STFT Based Timing Approach to OFDM Systems

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The Journal of China Universities of Posts and Telecommunications 2003年第4期10卷 23-27页

作者： KUANGYu-jun TENGYong YINChang-chuan: haojian-jun YUEGuang-xin ChongqingUniversityofPostsandTelecommunications Chongqing430005P.R.China SchoolofTelecommunicationEngineering BeijingUniversityofPostsandTelecommunicationsBeijing100876P.R.China

This paper mainly focuses on performance analysis of the previously proposedSTFT based 2-D timing approach to OFDM systems and presents simulations results of its performancein AWGN and multipath fading environment and its robustness against the duration of Channel ImpulseResponse (CIR) and frequency offset. Simulation results suggest that a revised version of Short-TimeFourier Transform (STFT) can be used to greatly reduce computational complexity, especially athigher SNR.

关键词： OFDM symbol timing short-time fourier transform (STFT) time- frequencyspectrum synchronization

A New Symbol Synchronization Scheme for Cyclic Prefix Based Systems

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The Journal of China Universities of Posts and Telecommunications 2003年第3期10卷 6-10页

作者： KUANGYu-jun TENGYong YINChang-chuan haojian-jun YUEGuang-xin ChongqingUniversityofPostsandTelecommunications Chongqing400065P.R.China TelecommunicationEngineeringSchool BeijingUniversityofPostsandTelecommunicationsBeijing100876P.R.China

This contribution proposes a new symbol synchronization scheme for cyclicprefix based modulation systems, which is disclosed in Ref.. The proposed algorithm involves twosteps . By using short-time Fourier transform, ISI-free intervals are estimated from time-frequencyspectrum of the received signal, and then an optimum symbol start time is obtained. Computersimulation results show that the algorithm is very robust, and outperforms those based upontime-domain correlations.

关键词： OFDM symbol timing short-time fourier transform (STFT) time-frequencyspectrum synchronization

The composition of magmatic-hydrothermal fluids and their related metal mineralization

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Science China Earth Sciences 2025年第1期68卷 208-225页

作者： Qihai SHU jun DENG State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and Resources China University of Geosciences Frontiers Science Center for Deep-time Digital Earth China University of Geosciences

Magmatic hydrothermal deposits are important sources of many bulk, precious, and rare metals, and have attracted interest from both academic and industrial communities. However, it is still unclear if the major enrichment of the ore-forming metals occurs in the parental magma source region, during the magma evolution, or after the fluid exsolution. Fluid inclusions trapped in hydrothermal minerals crystallized in the early, high-temperature stage before metal precipitation record information close to that of the initially exsolved magmatic fluids, which are helpful in revealing whether the metals have been already significantly enriched prior to the hydrothermal stage. In this study, available compositional data of such early-stage fluid inclusions from magmatic hydrothermal systems globally have been compiled. The results indicate that the concentrations of Cu,Sn, and W respectively from the Cu-, Sn-, and W-mineralized fluids are significantly higher than the hydrothermal systems that do not produce ores with the corresponding metals. This suggests that Cu, Sn, and W could have already been enriched in the magma source and/or magma evolution stage. The Mo concentrations show no difference between Mo-mineralized and Mobarren fluid systems, indicating no significant pre-enrichment in the source region or during the magma evolution. This also implies that an efficient collection of Mo from a large volume of magmas is required to account for the formation of a large Mo deposit. Almost all the hydrothermal fluids contain high concentrations of Fe and Zn-Pb, but only a few of them eventually form Fe or Zn-Pb deposits, reflecting an important role of the hydrothermal evolution process on the selective metal *** above results indicate that different metals are enriched in different stages of a magmatic hydrothermal system, and that the major roles played in the formation of a deposit vary with the metal types. In addition to the metal concentrations in the o

关键词： Magmatic hydrothermal deposits Fluid inclusions LA-ICP-MS Metal enrichment Mineralization mechanism

BR与S_(3307)复合剂对黄瓜壮苗及内源激素含量的影响

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北方园艺 2006年第4期 4-6页

作者：康宗利杨玉红郝建军周会娜于洋沈阳农业大学生物科学技术学院沈阳110160

利用BR与S3307混合对津研四号黄瓜进行浸种处理,结果表明,BR与S3307只有在较低浓度下混合,才起到显著的壮秧效应。BR与S3307复合处理降低了茎的IAA、GA含量,提高了ZR含量;提高了根的IAA和ZR水平,降低了GA含量;提高叶片IAA、GA和ZR含量,... 详细信息

利用BR与S3307混合对津研四号黄瓜进行浸种处理,结果表明,BR与S3307只有在较低浓度下混合,才起到显著的壮秧效应。BR与S3307复合处理降低了茎的IAA、GA含量,提高了ZR含量;提高了根的IAA和ZR水平,降低了GA含量;提高叶片IAA、GA和ZR含量,降低ABA含量,从而起到降低茎长,促进根、叶生长的作用。

关键词： BR S3307 复合剂黄瓜壮秧内源激素

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu Chen Xue-jun Li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

Approach from the laboratory to the field: New strategies in the control of mosquito-borne infectious diseases

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Science China Life Sciences 2025年第1期68卷 303-305页

作者： Ziqian Xu Lianpan Dai jun Liu National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases (NITFID) National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and Prevention CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences

Vector-borne viruses, transmitted among humans and animal hosts through bites of vectors such as mosquitoes and ticks,pose a great and ongoing threat to public health and biosafety(Yang et al., 2022).Among them, dengue virus-induced epidemics, have dramatically increased worldwide in recent decades. The report released by the World Health Organization(WHO) at the end of 2023 showed that dengue epidemic globally surged in2023, with the number of reported cases nearing a historical peak.

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Emerging progress: photochemical transformation of nitroso compounds

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Science China Chemistry 2025年第1期68卷 118-133页

作者： Ze-Le Chen Qiang-Qiang Li Armido Studer jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry & Chemical Engineering Anhui University Organisch-Chemisches Institut Universitat Münster

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles, nucleophiles, diradicals, and radical acceptors in diverse transformations. In recent years, notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions. Various nitroso compounds like nitrosoarenes, acyloxy nitroso compounds, N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access. In this review, we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds, with particular emphasis on their role as bifunctional reagents and acceptors of radicals, carbenes and nitrenes.

关键词： nitroso compounds photochemistry radical reaction carbene transformation nitrosoarenes

Turbulent Agglomeration of Microparticles in a Cylinder Wake Flow Using LES-DEM:Focusing on the Effect of the Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 34-49页

作者： WANG Shuang MU Lin LI Xue XIE jun DONG Ming School of Energy and Power Engineering Dalian University of Technology School of Optical Information and Energy Engineering Wuhan Institute of Technology School of Energy and Environment Shenyang Aerospace University

Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method（LES-DEM） *** validity of the LES approach was verified by comparison with available direct numerical simulation（DNS） *** adopted the Johnson-Kendall-Roberts（JKR） contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters（dp=2-20 μm） in the laminar and transition of shear layer（TrSL） flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise（y-direction）.With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.

关键词： discrete element method large eddy simulation microparticle particle agglomeration

High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation

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Neural Regeneration Research 2025年第1期20卷 107-115页

作者： Hanki Kim Bum jun Kim Seungyon Koh Hyo Jin Cho Xuelian Jin Byung Gon Kim jun Young Choi Department of Brain Science Ajou University School of MedicineSuwonSouth Korea Department of Biomedical Sciences Ajou University Graduate School of MedicineSuwonSouth Korea Department of Neurology Ajou University School of MedicineSuwonSouth Korea Department of Geriatrics The Affiliated Suqian First People’s Hospital of Nanjing Medical UniversitySuqianJiangsu ProvinceChina

High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and ***-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain *** drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system *** it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system *** this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory *** targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1.

关键词： central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 inflammation neural stem cells neurodevelopment oligodendrocyte progenitor cells redox status regeneration