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Plasma draining and replenishing near a solar active region inferred from cross-correlation between radiation intensity and Doppler shift

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Science China Earth Sciences 2015年第5期58卷 830-838页

作者： ZHANG JingBo HE JianSen yan LiMei tu ChuanYi WANG LingHua WANG Xin Institute of Space Physics and Applied Technology Peking University

Using observations from the EUV Imaging Spectrometer （EIS） onboard Hinode, we exam the plasma dynamics around the edge of the active region 10977, possibly associated with the source of nascent slow/intermediate solar wind. The correlation between the temporal profiles of the radiation intensity and Doppler shift for each emission line are analyzed. And three small regions with positive correlations for all the five emission lines are selected for a detailed analysis. In this work, Doppler blue （red） shift is defined as negative （positive）. We find that in Region 1, the radiation intensity （Doppler velocity） decreases by about 15% （about 3 km s-X）, and logarithmical differential emission measures （lg（DEMs）） reduces by about 0.06-0.10% at all temperatures, called ＂weak dimming＂, during a 30-min interval. In Region 2 and Region 3, however, the radiation intensity （Doppler velocity） increases by about 15% （about 3 km s-l）, and lg（DEMs） increases by about 0.06%~0.10% at all tempera- tures, called ＂weak brightening＂. Such weak dimming （weak brightening） could reflect a slow draining （replenishing） of plas- ma in the solar wind flux tubes, possibly due to a larger （smaller） outflow flux at high altitude than at low altitude. These sug- gest that the plasma supply could be intermittent with an alternation of draining and replenishing, for which the underlying physical process is yet unknown, at the source region of slow/intermediate solar wind.

关键词： solar corona solar wind active region

Ultrasensitive detection of cancer biomarker microRNA by amplification of fluorescence of lanthanide nanoprobes

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Nano Research 2018年第1期11卷 264-273页

作者： Lianyu Lu Datao tu yan Liu Shanyong Zhou Wei Zheng Xueyuan Chen College of Chemistry Fuzhou University Fuzhou 350116 China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou 350002 China

Sensitive detection of cancer biomarker microRNAs （miRNAs） is of vital importance for cancer diagnosis and treatment. Nonetheless, the detection sensitivity in the existing miRNA bioassays is severely limited by the structural characteristics of miRNA （including small length and high sequence homology） because most of these methods are based on target amplification. Herein, we report a novel approach to sensitive and specific detection of low-abundance miRNA via a unique strategy of nanoprobe dissolution-enhanced fluorescence amplification, in which a capture probe featuring molecular beacon structure is designed. By means of this strategy, miRNA-21 was detected in a linear range from 10 fM to 100 pM with a detection limit as low as 1.38 fM. High selectivity of the newly developed biosensor was demonstrated by the good discrimination against a target with a single-base mismatch. Furthermore, this assay was used for the detection of miRNA-21 added into fetal bovine serum samples with the recovery in the range of 90.2%--108% and coefficients of variation below 10.1%, indicating its promising applications to RNA immunoassays and early cancer diagnosis.

关键词： microRNA lanthanide nanoparticles fluorescence amplification cancer biomarker molecular beacon

Co-luminescence properties of terbium ions–benzoic acid–phen complexes doped with europium ions

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Rare Metals 2013年第6期32卷 599-604页

作者： Jing Zhang Li-Xi Wang Le Zhang yan Chen Qi-tu Zhang College of Materials Science and Engineering Nanjing University of Technology

Series of complexes Eux Tb1-x(BA)3phen(0.01 B x B 0.50)were synthesized by co-precipitation method,BA was used as the carboxylic acid ligand and 1,10-phenanthroline was used as the electrically neutral *** samples were characterized by means of X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),thermal gravimetric analyses and differential scanning calorimetry(TG–DSC),ultraviolet and visible spectrophotometer absorption spectra,and photoluminescence spectra to study the structure,the energy absorption,the thermal,and luminescent properties of the rare earth *** results show that the series rare earth organic complexes are well crystallized and show high thermal *** luminescent intensity of europium ion in the complexes increases as terbium ion transfers the absorbed energy to europium ion in the *** emission of terbium ion at 545 nm is not quenched by europium ion but increases with the content of europium ion *** the x value is 0.01,the fluorescence intensity reaches the maximum as well as the emission intensity of terbium ions at 545 nm and europium ions at614 nm are almost *** realizes the co-luminescence phenomenon of terbium ion and europium *** series rare earth organic complexes with different colors can be obtained by adjusting the ratio of terbium ion and europium ion.

关键词： Complexes Photoluminescence Rare earth Luminescent intensity Co-luminescence

Neuroprotection of Cyperus esculentus L. orientin against cerebral ischemia/reperfusion induced brain injury

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Neural Regeneration Research 2020年第3期15卷 548-556页

作者： Si-Qun Jing Sai-Sai Wang Rui-Min Zhong Jun-yan Zhang Jin-Zi Wu Yi-Xian tu yan Pu Liang-Jun yan Yingdong College of Food Science and Engineering Shaoguan UniversityShaoguanGuangdong ProvinceChina School of Bioengineering Jiangnan UniversityWuxiJiangsu ProvinceChina Department of Pharmaceutical Sciences UNT System College of PharmacyUniversity of North Texas Health Science CenterFort WorthTXUSA College of Life Sciences and Technology Xinjiang UniversityUrumqiXinjiang Uygur Autonomous RegionChina

Orientin is a flavonoid *** recent years,its importance as a source of pharmacological active substance is growing rapidly due to its properties such as anti-myocardial ischemia,anti-apoptosis,anti-radiation,anti-tumor,and ***,the neuroprotective effects of Orientin on stroke injury have not been comprehensively *** aim of the present study was thus to investigate the neuroprotective capacity and the potential mechanisms of Cyperus esculentus ***(CLO)from Cyperus esculentus *** against ischemia/reperfusion(I/R)injury using standard orientin as *** in vitro studies,we treated HT22 cells with CoCl2 as an in vitro ischemic injury ***22 cells in the control group were treated with *** in vivo studies,we used rat models of middle cerebral artery occlusion,and animals that received sham surgery were used as *** found that CLO protected CoCl2-induced HT22 cells against ischemia/reperfusion injury by lowering lipid peroxidation and reactive oxygen species formation as well as decreasing protein ***,CLO did not reduce the release of lactate dehydrogenase nor increase the activity of superoxide *** showed that CLO could decrease neurological deficit score,attenuate brain water content,and reduce cerebral infarct volume,leading to neuroprotection during cerebral ischemia-reperfusion *** studies indicate that CLO flavonoids can be taken as a natural antioxidant and bacteriostastic substance in food and pharmaceutical *** molecular mechanisms of CLO could be at least partially attributed to the antioxidant properties and subsequently inhibiting activation of *** experimental procedures and protocols were approved on May 16,2016 by the Experimental Animal Ethics Committee of Xinjiang Medical University of China(approval ***20160516-57).

关键词： antioxidants caspase-3 cerebral ischemia/reperfusion injury cobalt chloride Cyperus esculentus L.orientin(CLO) lipid peroxidation nerve regeneration neurological deficits oxidative stress reactive oxygen species

Successful transcatheter arterial embolization treatment for chest wall haematoma following permanent pacemaker implantation: A case report

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World Journal of Clinical Cases 2022年第32期10卷 11877-11881页

作者： Jing Zheng Xiao-Ming tu Zhen-yan Gao Department of Cardiology The Quzhou Affiliated Hospital of Wenzhou Medical UniversityQuzhou People’s HospitalQuzhou 324000Zhejiang ProvinceChina

BACKGROUND Haematoma is one of the main complications associated with pacemaker *** is a rare condition that is not easy to identify and is often *** SUMMARY A female patient diagnosed with high-grade atrioventricular block underwent permanent pacemaker *** the operation,puncturing a small branch of the right subclavian artery developed into a pseudoaneurysm and resulted in further haematoma *** treatment of compression haemostasis and haemostatic drugs was not effective.A series of timely transcatheter arterial embolizations avoided serious *** More possible conditions should be taken into consideration as haematoma is discovered,and timely treatment might prevent severe adverse events.

关键词： Permanent pacemaker implantation Haematoma Pseudoaneurysm Transcatheter arterial embolization Case report

Permeability and Sedimentation Characteristics of Pleistocene Fluvio-glacial Deposits in the Dadu River Valley,Southwest China

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Journal of Mountain Science 2013年第3期10卷 482-493页

作者： tu Guo-xiang HUANG Run-qiu DENG Hui LI yan-rong State Key Laboratory of Geo-hazard Prevention and Geo-environment Protection Chengdu University of Technology Department of Earth Sciences The University of Hong Kong

There exist many fluvio-glacial deposits in the valley of Dadu River, Southwest China, which dates back to the Pleistocene. As some of the deposits are located within the seasonal water fluctuation zone of reservoirs, the seepage of groundwater acts as one of the key factors influencing their stability. Investigation into the sediment properties and permeability is, therefore, crucial for evaluating the sediment stability. In this study, in-situ permeability and sieving tests have been carried out to determine grain size distribution, correlations of permeability and hydraulic gradients, and relations between permeability and sedimentation properties. Test results indicate that the deposits are composed mostly of sands, gravels, cobbles and boulders, and the percentage of fines is less than 5%. The sediments have high densities, low porosities and natural moisture contents. At low hydraulic gradients, the seepage velocity obeys the Darcy＇s law, while a non- Darcy permeability is observed with hydraulic gradient exceeding a certain value （about 0.5 - 0.7）. The linear permeability coefficient ranges from 0.003 to 0.009 cm/s. Seepage failure occurs above a threshold between 1.1 and 1.5. The test data fit well with the non-linear permeability equations suggested by Forchheimer and Izbash. The non-Darcy permeability proves to be in accordance with the seepage equation suggested by Izbash with the power ＇m＇ of about 0.6 - 0.7. The characteristic grain sizes of the studied deposits are found in a narrow range between 0.024 and o.o31 mm, which is much lowerthan the effective grain size （dlo）.

关键词： Fluvio-glacial deposits Grain sizedistribution Linear and non-linear permeability Seepage failure

Synthesis of Multi-substituted Benzamide Derivatives under Microwave Irradiation Conditions

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Chinese Journal of Chemistry 2011年第9期29卷 1869-1872页

作者： Jia, Runhong Peng, Juhua Ma, Ning yan, Shu tu, Shujiang Lianyungang Teacher＇s College Lianyungang Jiangsu 222006 China College of Chemistry and Chemical Engineering Xuzhou Normal University Xuzhou Jiangsu 221116 China

A facile microwave-assisted synthesis of N-[（Z）-1-（substituted carbamoyl）-2-arylvinyl] benzamide derivatives is accomplished via reactions of 4-arylmethylene-2-phenyloxazol-5（4H）-ones with different amines （for example me- thylamine, cyclopropylamine, para-toluidine, phenylarnine） in ethylene glycol. This protocol broadens the scope of the reaction for the synthesis of N-benzamide derivatives.

关键词： amides microwave irradiation open loop amines

Shell Model for Elastic and Thermodynamic Properties of Gallium Nitride with Hexagonal Wurtzite Structure

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Communications in Theoretical Physics 2008年第12期50卷 1443-1448页

作者： CHENG yan tu Ya-Jing ZENG Zhao-Yi GOU Qing-Quan College of Physical Science and Technology Sichuan University Chengdu 610064 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China School of Computer Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

Shell model molecular dynamic simulation with interatomic pair potential is utilized to investigate the elastic and thermodynamic properties of gallium nitride with hexagonal wurtzite structure （w-GaN） at high pressure. The calculated elastic constants Cij at zero pressure and 300 K agree well with the experimental data and other calculated values. Meanwhile, the dependences of the relative volume V/Vo, elastic constants Cij, entropy S, enthalpy H, and heat capacities Cv and Up on pressure are successfully obtained. From the elastic constants obtained, we also calculate the shear modulus G, bulk modulus B, Young＇s modulus E, Poisson＇s ratio v, Debye temperature ΘD, and shear anisotropic factor Ashear on pressures.

关键词： shell model molecular dynamics elastic properties thermodynamic properties GaN

Science Letters:Determination of benzalkonium chloride in viscous ophthalmic drops of azithromycin by high-performance liquid chromatography

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第12期10卷 877-882页

作者： yan SHEN Sheng-jie XU Shi-chun WANG Jia-sheng tu Department of Pharmaceutics China Pharmaceutical University Nanjing 210009 China Productivity Center of Jiangsu Province Nanjing 210042 China

A high-performance liquid chromatography （HPLC） system was used in the reversed phase mode for the determination ofbenzalkonium chloride （BKC） in azithromycin viscous ophthalmic drops. A Venusil-XBP（L）-C18 （150 mm×4.6 mm, 5 gm） column was used at 50℃. The mobile phase consisted of a mixture of methanol-potassium phosphate （16：5, v/v）. Two sample preparation methods were compared. The results suggested that, compared with an extraction procedure, a deproteinization procedure was much quicker and more convenient. Using the deproteinization procedure for sample preparation, calibration curves were linear in the range 5.0-50μg/ml. The within-day and inter-day coefficients of variation were less than 10%. The average recoveries were determined as 96.70%, 98.52%, and 97.96% at concentrations of 10.0, 30.0, and 50.0 μg/ml, respectively. Variability in precision did not exceed 5%. In conclusion, this HPLC method using a simple sample treatment procedure appears suitable for monitoring BKC content in azithromycin viscous ophthalmic drops.

关键词： Benzalkonium chloride High-performance liquid chromatography Azithromycin Viscous ophthalmic drops