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Information Conductivity:Universal Performance Measure for Semantic Communications

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China Communications 2024年第7期21卷 17-36页

作者： Liang Zijian niu Kai Zhang ping Key Laboratory of Universal Wireless Communications Ministry of Education(Beijing University of Posts and Telecommunications)Beijing 100876China Peng Cheng Laboratory Shenzhen 518055China State Key Laboratory of Networking and Switching Technology(Beijing University of Posts and Telecommunications) Beijing 100876China

As a novel paradigm,semantic communication provides an effective solution for breaking through the future development dilemma of classical communication ***,it remains an unsolved problem of how to measure the information transmission capability for a given semantic communication method and subsequently compare it with the classical communication *** this paper,we first present a review of the semantic communication system,including its system model and the two typical coding and transmission methods for its *** address the unsolved issue of the information transmission capability measure for semantic communication methods,we propose a new universal performance measure called Information *** provide the definition and the physical significance to state its effectiveness in representing the information transmission capabilities of the semantic communication systems and present elaborations including its measure methods,degrees of freedom,and progressive *** results in image transmission scenarios validate its practical applicability.

关键词： information conductivity information transmission capability semantic communications system model universal performance measure

Dilated left ventricle with multiple outpouchings—a severe congenital ventricular diverticulum or left-dominant arrhythmogenic cardiomyopathy:A case report

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World Journal of Clinical Cases 2022年第18期10卷 6289-6297页

作者： Xin Zhang run-Yu Ye Xiao-ping Chen Department of Cardiology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Left-dominant arrhythmogenic cardiomyopathy(LDAC)is a relatively rare disease characterized by poor prognosis that exacerbates the incidence of sudden cardiac death and ventricular ***,LDAC is constantly overlooked or misdiagnosed as myocardial infarction,myocarditis,and dilated cardiomyopathy,owing to atypical and nonspecific clinical manifestations at an early *** SUMMARY A 57-year-old woman was diagnosed with sinus bradycardia and chronic bifascicular block during a health *** occasionally experienced mild chest pain and paroxysmal palpitation during activity in the past 2 *** auxiliary examinations,including electrocardiogram,echocardiography,coronary computerized tomography angiography,and magnetic resonance imaging,revealed that she had LDAC instead of congenital ventricular *** physicians prescribed standard oral therapy for heart failure and implantable ***,her left ventricular systolic function and symptoms remained stable at the 2-year follow-up after *** Based on this case,clinicians need to be aware of LDAC in patients with localized left ventricular lesions and multiple electrocardiographic *** cardiovascular imaging is effective in identification of multiple types of cardiomyopathy and cardiac inner structures.

关键词： Congenital ventricular diverticulum Left-dominant arrhythmogenic cardiomyopathy Magnetic resonance imaging Case report

Sand source and formation mechanism of riverine sand dunes: a case study in Xiangshui River, China

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Journal of Arid Land 2019年第4期11卷 525-536页

作者： WANG Yong YAN ping HAN Guang WU Wei ZHANG run Faculty of Geographical Science Beijing Normal UniversityBeijing100875China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China College of Resources and Environment Hunan Normal UniversityChangsha410081China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChineseAcademy of SciencesBeijing100101China

Riverine sand dunes develop as a result of fluvial-aeolian interactions. The primarily barchan dune chains along the Xiangshui River(a branch of the Xar Moron River in the western part of the Horqin Sandy Land of China) form a typical riverine dune field. We collected a series of samples from the riverine sand dunes parallel to the direction of the prevailing wind and investigated the sand sources and formation mechanisms of these dunes by determining the grain size, heavy mineral content and optically stimulated luminescence(OSL) of the samples. The sand of the near-river dunes was coarser than the sand of the dunes distant from the river, indicating that coarse sand of the valley mainly deposited on near-river dunes. The heavy mineral analysis suggested that wind-sand activity levels were intense on the upwind dunes, but relatively weak on the downwind dunes. This indicated that the sand sources for the near-river dunes were more abundant than those of the distant dunes. Our OSL analysis of samples suggested that the deposition rates on dunes near the river were greater than the deposition rates on dunes distant from the river. The development of dunes along the river indicated that the river played an important role in dune formation and development. In addition, airflow fluctuation and the formation of the waveform dunes had a type of feedback relationship. Grain size, heavy mineral and OSL analyses are widely used methods in wind-sand research. Sand dune grain size characteristics reflect the effects of airflow on the transport and separation of sand materials, as well as the physical characteristics of the sand sources. Heavy mineral characteristics are often used to investigate the relationships between sediments and sand sources. OSL indicates dune age, revealing formation of dunes. Therefore, it is useful to explore dune sand sources, as well as the mechanisms underlying dune formation, by determining grain size, heavy mineral content and OSL. This study in

关键词： riverine dune grain size heavy mineral optically stimulated luminescence(OSL) Horqin Sandy Land

A new neuroprotective bakkenolide from the rhizome of Petasites tricholobus

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Chinese Chemical Letters 2008年第7期19卷 841-844页

作者： Na Zhang Mei Li Guo Ge Zhang run ping Li Department of Pharmacognosy School of Pharmacy Second Military Medical University Shanghai 200433 China Department of Diving Medicine Faculty of Naval Medicine Second Military Medical University Shanghai 200433 China

A new bakkenolide-type compound, bakkenolide-Va（1）, was isolated from the rhizome of Petasites tricholobus. The structure was characterized on the basis of various NMR （1H, 13C, 1H-1H COSY, HMQC, HMBC and NOESY） and mass spectrometry data. The neuroprotective activity of bakkenolide-Va was investigated in primarily cultured neurons treated by hypoxia-ghicose deprivation and various types of oxidative insults.

关键词： Petasites tricholobus Compositae Bakkenofide-Va Neuroprotection

Crystal Structure of the 1:2 Stoichiometric Nd: [α-SiW_(11)O_(39)]^(8-): K_5Na_5H_3[Nd(α-SiW_(11)O_(39))_2]·6H_2O

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Chinese Journal of Structural Chemistry 2007年第2期26卷 234-238页

作者： HAN Qiu-Xia WANG Jing-ping niu Jing-Yang Basic Experiment Teaching Center Henan University Kaifeng 475001 China Institute of Molecular and Crystal Engineering School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China

Single-crystal X-ray structural analysis of K5Na5H3[Nd（α-SiW11O39）2]·6H2O （triclinic, space group P1^-, a = 13.7738（10）, b = 19.722（2）, c = 20.6647（15） A, α = 111.0090（10）, β = 105.1740（10）, y = 98.6870（10）°, Z = 2, V = 4867.2（8）, Mr = 5914.40, Dc = 4.026,μ = 26.754 mm^-1, F（000） = 5076, R = 0.0750 and wR = 0.2077） reveals that two [α-SiW11O39]^8- moieties are connected through one Nd atom which is in a square antiprismatic coordination environment by eight oxygen atoms from two [α-SiW11O391]^8- moieties. The Nd（Ⅲ） ion is substituted for a [WO]^4＋ unit in the ＂cap＂ region of the tungsten-oxygen framework of the parent Keggin ion. Disordered Na^＋ cations and water molecules reside outside these channels, leaving empty pores with an intersecting slot （13 A × 10 A）.

关键词： crystal structure characterization polyoxometalates

On the Red Edge of the δ Scuti Instability Strip

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Chinese Journal of Astronomy and Astrophysics 2002年第5期2卷 441-448页

作者： Yan Xu Zhi-ping Li Li-Cai Deng Da-run Xiong National Astronomical Observatories Chinese Academy of SciencesBeijing 100012 Department of Physics Tianjin Normal UniversityTianjin 300073 Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008

The δ Scuti star catalogue is used to derive the observational locations of such stars on the HR diagram. The theoretical and observational instability strips are compared to check the theoretical red edge obtained by considering nonlocal time-dependent convection theory. The observational instability strip almost overlaps with the theoretical one, but the observed blue and red envelopes are hotter than the theoretical edges. The distribution of δ Scuti stars in the pulsation strip is not uniform.

关键词： stars: variables: δ Sct - stars: oscillations ?stars: HR diagram

Influence of Different Ratios of Cobalt and Copper Supplementation on Vitamin B_(12) Status and Nutrient Utilization in Sheep

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Agricultural Sciences in China 2010年第12期9卷 1829-1835页

作者： WANG run-lian ZHANG Wei ZHU Xiao-ping JIA Zhi-hai College of Animal Science and Technology China Agricultural University Beijing 100193 PR.China Department of Animal Science Guangdong Ocean University Zhanjiang 524088 P.R.China

The present study is aimed to investigate the effects of different ratios of cobalt （Co） and copper （Cu） supplementation on vitamin B12 status and nutrient utilization in sheep. Twenty wether lambs with an average weight （22.9 ± 0.8） kg were randomly divided into five groups and fed with the control diet which was supplied with 0.3 mg kg^-1 DM （dry matter） of Co to the basal diet, and four supplemental diets which were supplied either 0.3 or 0.6 mg kg^-1 DM of Co and 10 or 20 mg kg^-1 DM of Cu to the basal diet, respectively for 8 wk. The supplementation of Co and Cu with different levels improved plasma vitamin B12 concentration which was increased with feeding time, but stable after 6 wk. Vitamin B12 status was accounted for Co intake with no combined effects by supplementation of different levels of Co and Cu. The plasma concentrations of methylmalonic acid, homocysteine, folic acid, and glucose did not show the consistent results with plasma vitamin B12, which was considered to be resulted from Cu action. Addition of Co and Cu with different levels had no influence on digestibility of dry matter （DM）, organic matter （OM）, crude protein （CP） and nitrogen free （NFE）, and N metabolism （P〉 0.05）, but the digestibility of fat and fibre （P〈0.01） was enhanced by supplementation of 0.3 mg kg^-1 DM of Co and 20 mg kg^-1 DM of Cu. In conclusion, the supplementation of Co and Cu with different levels has no influence on vitamin B12 status. The optimum ratio of Co and Cu in diet could enhance the nutrient utilization.

关键词： cobalt vitamin B12 sheep nutrient utilization

An immortalized rat pancreatic stellate cell line RP-2 as a new cell model for evaluating pancreatic fibrosis,inflammation and immunity

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Hepatobiliary & Pancreatic Diseases International 2015年第6期14卷 651-659页

作者： Rong-Li Piao Ming Xiu David R Brigstock run-ping Gao Department of Hepatic-biliary-pancreatic Medicine the First Hospital of Jilin University The Research Institute at Nationwide Children's Hospital Division of Pediatric Surgery Department of Surgerythe Ohio State University

BACKGROUND： Pancreatic stellate cells （PSCs） play a critical role in the pathogenesis of pancreatic fibrosis and have emerging functions as progenitor cells, immune cells or intermediaries in pancreatic exocrine secretion. Increasing evidence has shown that desmin as an exclusive cytoskeleton marker of PSC is only expressed in part of these cells. This study was to establish a desmin-positive PSC cell line and evaluate its actions on pancreatic fibrosis, inflammation and immunity.

关键词： pancreatic stellate cell pancreatic fibrosis Toll-like receptor 4 inflammation immunity

Involvements of chloride ion in decolorization of Acid Orange 7 by activated peroxydisulfate or peroxymonosulfate oxidation

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Journal of Environmental Sciences 2011年第11期23卷 1799-1807页

作者： ping Wang Shiying Yang Liang Shan Rui niu Xueting Shao Key Laboratory of Marine Environment and Ecology Ministry of EducationQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Department of Civil and Structural Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina

The effects of chloride anion （Cl-）（up to 1.0 mol/L） on the decolorization of a model compound,azo dye Acid Orange 7 （AO7）,by sulfate radical （SO4-） based-peroxydisulfate （PS） or peroxymonosulfate （PMS） oxidation under various activated conditions （UV 254 nm /PS,Thermal （70°C/PS,UV 254 nm /PMS,Co 2＋ /PMS） were *** and NH4 ＋ were used as quenching reagents to determine the contributions of active chlorine species （dichloride radical （Cl2-.） and hypochlorous acid （HClO））.The results indicated that the effects of Cl- on the reaction mechanism were different under various activated *** UV/PS and Thermal/PS,the inhibition tendency became more clear as the Cl- concentration increased,probably due to the reaction between Cl- and SO4-.and the generation of Cl2-.or *** UV/PMS,Cl- did not exhibit inhibition when the concentration was below 0.1 mol/*** Cl- concentration reached to 1.0 mol/L,the decolorization rate of AO7 was,however,accelerated,possibly because PMS directly reacts with Cl- to form *** Co2＋ /PMS,Cl- exhibited a significant inhibiting effect even at low concentration （ 0.01 mol/L）.When Cl- concentration exceeded 0.1 mol/L,the activation of PMS by Co 2＋ was almost completely *** this condition,HClO maybe played a major role in decolorization of *** results implicated that chloride ion is an important factor in SO4-.-based degradation of organic contamination in chloride-containing water.

关键词： chloride anion activated peroxydisulfate oxidation activated peroxymonosulfate oxidation radicals decolorization