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等效频谱带宽分配的多媒体CDMA系统媒质接入控制

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通信学报 2006年第6期27卷 126-133页

作者：潘甦酆广增南京邮电大学通信与信息工程学院

提出了一种基于等效带宽分配的媒质接入控制(MAC)方法,它针对CDMA系统是“误码率受限”型系统这一特点,将多媒体业务不同的误码率要求映射为等效带宽。系统根据流量动态地将等效带宽分配给不同业务。仿真结果表明,相比与已有的CDMA系统... 详细信息

提出了一种基于等效带宽分配的媒质接入控制(MAC)方法,它针对CDMA系统是“误码率受限”型系统这一特点,将多媒体业务不同的误码率要求映射为等效带宽。系统根据流量动态地将等效带宽分配给不同业务。仿真结果表明,相比与已有的CDMA系统的MAC方法,本方法具有更好的吞吐量性能。

关键词： CDMA 多媒体媒质接入控制等效带宽

Facilitating effects of berberine on rat pancreatic islets through modulating hepatic nuclear factor 4 alpha expression and glucokinase activity

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World Journal of Gastroenterology 2008年第39期14卷 6004-6011页

作者： Zhi-Quan Wang Fu-Er Lu San-Hua Leng Xin-Sheng Fang guang Chen zeng-Si Wang Li-Ping Dong Zhong-Qing Yan Institute of Integrated Traditional Chinese and Weestern Medicine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei Province China

AIM： To observe the effect of berberine on insulin secretion in rat pancreatic islets and to explore its possible molecular mechanism. METHODS： Pdmary rat islets were isolated from male Sprague-Dawley rats by collagenase digestion and treated with different concentrations （1, 3, 10 and 30 μmol/L） of berberine or 1 μmol/L Glibenclamide （GB） for 24 h. Glucose-stimulated insulin secretion （GSIS） assay was conducted and insulin was determined by radioimmunoassay. 3-（4,5-Dimethylthiazol-2-yl）- 2,5-diphenyltetrazolium bromide （MTT） assay was performed to evaluate cytotoxicity. The mRNA level of hepatic nuclear factor 4 alpha （HAIF4α） was determined by reverse transcription polymerase chain reaction （RT-PCR）. Indirect immunofluorescence staining and Western blot analysis were employed to detect protein expression of HNF4α in the islets. Glucokinase （GK） activity was measured by spectrophotometric method. RESULTS： Berberine enhanced GSIS rather than basal insulin secretion dose-dependently in rat islets and showed no significant cytotoxicity on islet cells at the concentration of 10 μmol/L. Both mRNA and protein expressions of HNF4α were up-regulated by berberine in a dose-dependent manner, and GK activity was also increased accordingly. However, GB demonstrated no regulatory effects on HNF4α expression or GK activity. CONCLUSION： Berberine can enhance GSIS in rat islets, and probably exerts the insulinotropic effect via a pathway involving HNF4α and GK, which is distinct from sulphonylureas （SUs）.

关键词： Berberine Sulphonylureas Hepatocyte nuclear factor 4 alpha Glucokinase Pancreatic islet

Light-induced stepped thermal relaxation in a Hofmann-type metal-organic framework

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Science China Chemistry 2024年第6期67卷 1983-1989页

作者： Wen Cui Wei-Wei Wu Ze-Yu Ruan Yan-Cong Chen guang-Jun zeng Guan-Xi Chen Si-Guo Wu Zhao-Ping Ni Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistryInstitute of Green Chemistry and Molecular EngineeringGuangdong Basic Research Center of Excellence for Functional Molecular EngineeringSun Yat-sen UniversityGuangzhou510275China

Spin-crossover(SCO)materials with light-induced multistability have potential applications in multi-addressable opto-magnetic memory devices and multiple ***,we reported a three-dimensional Hofmann-type metal-organic framework(MOF)[Fe(bpy){Pt(CN)_(4)}]·coumarin(1·coumarin,bpy=4,4′-bipyridine),which exhibits an incomplete and hysteretic SCO *** importantly,the light-induced stepped thermal relaxation(LISTR)with obvious magnetic plateau for a hidden intermediate spin state is firstly *** hidden spin state is also observed for the first time in the thermal relaxation after light-assisted spin state annealing(LASSA).Meanwhile,an extremely rare bi-directional light-induced excited spin-state trapping(LIESST)with the highest reverse-LIESST temperature is ***,five spin states can be captured in 1·coumarin and the tristability can be modulated below 102 K through the excitation-relaxation ***,the light-and temperatureinduced multistability provides a new strategy for developing multistable materials.

关键词： light magnetic multistability iron metal-organic framework spin-crossover

A new prenylated arylbenzofuran derivative from Morus alba L.

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Chinese Chemical Letters 2010年第3期21卷 329-331页

作者： Tian, Hai Ying He, Xi zeng, guang Yao Tan, Jian Bin Shuang, Fu Liu, Guo Ru Tan, Gui Shan Zhou, Ying Jun Cent S Univ Sch Pharmaceut Sci Changsha 410013 Hunan Peoples R China Changzhi Med Coll Changzhi 047000 Shanxi Peoples R China

2-[3,5-Di-O-β-D-glucosyl-4-(3-methylbut-2-enyl)phenyl]benzofuran-6-ol,a new prenylated arylbenzofuran derivative was isolated from Morus alba *** structure was elucidated by various spectroscopic methods including MS... 详细信息

关键词： Morus alba L. Prenylated arylbenzofuran 2-[3 5-Di-O-β-D-glu-4-(3-methylbut-2-enyl)phenyl]benzofuran-6-ol

Chinese sunspot drawings and their digitization–(Ⅱ)accuracy analysis for digitized sunspot hand-drawing records of Yunnan Observatories

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Research in Astronomy and Astrophysics 2020年第4期20卷 156-162页

作者： Yang Peng Xiao-Yu Luo Shu-guang zeng Lin-Hua Deng Sheng Zheng Gang-Hua Lin Yu-Lin Cheng Jin-Ping Tao Yong-Li Feng College of Science China Three Gorges UniversityYichang 443002China Yunnan Observatories Chinese Academy of SciencesKunming 650216China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Chongqing University of Arts and Sciences Chongqing 402160China

Sunspots are the most striking and easily observed magnetic structures of the Sun,and statistical analysis of solar historical data could reveal a wealth of information on the long-term variation of solar activity *** hand-drawn sunspot records of Yunnan Observatories,Chinese Academy of Sciences have been accumulating for more than 60 years,and nearly 16000 images have been *** the future,the observation mode of recording sunspots by hand-drawing will be replaced inevitably by digital images observed either at ground or in *** connect the hand-drawn sunspot data and the purely digital sunspot data in future,it is necessary to analyze the systematic errors of the data which are observed by the two observation modes in the period of *** this paper,we choose 268 round sunspots(Htype in modified Zurich sunspot classification)from the drawing of Yunnan Observatories to compare their positions and areas with the CCD observations made by Helioseismic and Magnetic Imager(HMI)on board Solar Dynamic Observatory(SDO)and Global Oscillation Network Group(GONG).We find that the latitude and longitude accuracy of hand-drawn sunspot are within-0.127 and 2.29 degree respectively,and the area accuracy is about 16.36 sunspot unit(μHem).Systematic errors apparently decrease with large sunspot.

关键词： sunspots methods:data analysis techniques:image processing

Application of numerical simulation on optimum design of two-dimensional sedimentation tanks in the wastewater treatment plant

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Journal of Environmental Sciences 2003年第3期15卷 346-350页

作者： zeng guang-ming,ZHANG Shuo-fu, QIN Xiao-sheng, HUANG Guo-he, LI Jian-bing (Department of Environmental Science and Engineering of Hunan University, Changsha 410082, China.) Department of Environmental Science and Engineering of Hunan University Changsha 410082

The paper establishes the relationship between the settling efficiency and the sizes of the sedimentation tank through the process of numerical simulation, which is taken as one of the constraints to set up a simple optimum designing model of sedimentation tank. The feasibility and advantages of this model based on numerical calculation are verified through the application of practical case.

关键词： numerical simulation sedimentation tank optimum design

Food allergy and related risk factors in 2540 preschool children: an epidemiological survey in guangdong Province, southern China

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World Journal of Pediatrics 2015年第3期11卷 219-225页

作者： guang-Qiao zeng Jia-Ying Luo Hui-Min Huang Pei-Yan Zheng Wen-Ting Luo Ni-Li Wei Bao-Qing Sun State Key Laboratory of Respiratory Disease National Clinical Research Center for Respiratory DiseasesGuangzhou Institute of Respiratory DiseasesFirst Affiliated HospitalGuangzhou Medical UniversityGuangzhouChina

Background:Although the number of studies on allergic diseases in the general population of southern China is increasing,only a few have addressed food allergy(FA)in children in this *** present study aimed to investigate the prevalence,clinical manifestations,spectrum of allergens,and related risk factors of FA in preschool children in guangdong Province,southern ***:A random cluster-sampling method was used to select 24 kindergartens from 12 cities in guangdong *** parents or guardians of the children were requested to complete a questionnaire on general information and data regarding FA diagnosis and symptoms in the children and their first-degree ***,the Chi-square test,multivariate regression analysis,and Spearman's rank-order correlation coefficient analysis were performed to identify statistically significant ***:Analysis of 2540 valid questionnaires revealed an FA prevalence rate of 4%.Adverse food reactions were due to the consumption of shrimp(4.4%),crab(3.2%),mango(2.3%),cow's milk and dairy products(1.9%),and eggs(1.4%).Logistic regression analysis indicated that a history of FA and a history of allergic rhinitis in the first-degree relatives were the major factors leading to FA in ***:The incidence of FA in children in guangdong Province is higher than that commonly *** individual's genetic background is an important risk factor for ***,mitigation of the impact of lifestyle and environmental factors should be carefully considered to reduce the incidence of childhood FA.

关键词： allergic rhinitis eczema epidemiology food allergy questionnaire

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多径非相关瑞利信道生成的改进

通信学报 2007年第5期28卷 122-125页

作者：王欣酆广增南京邮电大学通信与信息工程学院江苏南京210003

提出一种多径非相关瑞利信道生成改进方法。和目前其他瑞利信道生成方法相比,该方法不仅能满足瑞利信道所具备的统计特性,而且保证信号多径传播中各径信号不相关特性。通过仿真可以看出该方法的单径信道二阶特性和现有模型统计特性相仿... 详细信息

提出一种多径非相关瑞利信道生成改进方法。和目前其他瑞利信道生成方法相比,该方法不仅能满足瑞利信道所具备的统计特性,而且保证信号多径传播中各径信号不相关特性。通过仿真可以看出该方法的单径信道二阶特性和现有模型统计特性相仿,而多径非相关性明显较好。

关键词：瑞利信道多径信道生成非相关 SOS模型 Jakes模型

Polarization-induced photocurrent switching effect in heterojunction photodiodes

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Nano Research 2023年第4期16卷 5503-5510页

作者： Dingbo Chen Yu-Chang Chen guang zeng Yu-Chun Li Xiao-Xi Li Dong Li Chao Shen Nan Chi Boon S.Ooi David Wei Zhang Hong-Liang Lu State Key Laboratory of ASIC and System Shanghai Institute of Intelligent Electronics&SystemsSchool of MicroelectronicsFudan UniversityShanghai 200433China Key Laboratory for Information Science of Electromagnetic Waves Department of Communication Science and EngineeringFudan UniversityShanghai 200433China Photonics Laboratory Division of ComputerElectricaland Mathematical Sciences and EngineeringKing Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdom of Saudi Arabia

The unipolar photocurrent in conventional photodiodes(PDs)based on photovoltaic effect limits the output modes and potential versatility of these devices in *** photodiodes with photocurrent switching are emerging as a promising solution for obtaining photoelectric devices with unique and attractive functions,such as optical logic ***,we design an all-solid-state chip-scale ultraviolet(UV)PD based on a hybrid GaN heterojunction with engineered bipolar polarized electric *** introducing the polarization-induced photocurrent switching effect,the photocurrent direction can be switched in response to the wavelength of incident light at 0 V *** particular,the photocurrent direction exhibits negative when the irradiation wavelength is less than 315 nm,but positive when the wavelength is longer than 315 *** device shows a responsivity of up to−6.7 mA/W at 300 nm and 5.3 mA/W at 340 nm,*** particular,three special logic gates in response to different dual UV light inputs are demonstrated via a single bipolar PD,which may be beneficial for future multifunctional UV photonic integrated devices and systems.

关键词： GaN heterostructure ultraviolet(UV)photodiodes bipolar photocurrent optical logic device