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Express and sensitive detection of multiple miRNAs via DNA cascade reactors functionalized photonic crystal array

Science China Chemistry 2020年第5期63卷 731-740页

作者： yingfei Wang Yuyi Li Yue Zhang Kewei Ren Huangxian ju ying Liu State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Chemistry and Biomedicine Innovation Center Nanjing UniversityNanjing 210023China Department of Chemistry University of MassachusettsAmherstMassachusetts 01003USA

Array based detection techniques with fluorescence signal reading is a powerful tool for multiple targets analysis. However,when applied fluorescence array for micro RNA detection, time-consuming multi-steps surface signal amplification is usually required due to the low abundance of micro RNA in total RNA expressions, which impairs detection efficiency and limits its application in point of care test(POCT) manner. Herein, DNA cascade reactors(DCRs) functionalized photonic crystal(PC)array was fabricated for express and sensitive detections of mi RNA-21 and mi RNA-155. DCRs were assembled by interval conjugation of self-quenched hairpin DNA probes to single strand DNA nanowire synthesized by rolling circle amplification,which generated cascade DNA hybridization reactions in response to target mi RNAwith instant fluorescence recovery signal. PC array patterns with multi-structure colors further amplified fluorescence with their respective photonic bandgaps(PBGs)matching with the emission peaks of fluorescence molecules labelled on DCRs. The as-prepared DCRs functionalized PC array demonstrated express and sensitive simultaneous detections of mi RNA-21 and mi RNA-155 with hundreds f M detection limits only in 15 min, and was successfully applied in fast quantifications of low abundance mi RNAs from cell lysates and spiked mi RNAs from human serum, which would hold great potential for disease diagnosis and therapeutic effect monitoring with a POCT manner.

关键词： micro RNA detection photonic crystal array DNA cascade reactors fluorescence amplification express detection

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Dynamic mass variation and multiphase interaction among steel, slag, lining refractory and nonmetallic inclusions: Laboratory experiments and mathematical prediction

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International Journal of minerals,Metallurgy and Materials 2021年第8期28卷 1298-1308页

作者： ju-jin Wang Li-feng Zhang Gong Cheng Qiang Ren ying Ren School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China

The mass transfer among the multiphase interactions among the steel, slag, lining refractory, and nonmetallic inclusions during the refining process of a bearing steel was studied using laboratory experiments and numerical kinetic prediction. Experiments on the system with and without the slag phase were carried out to evaluate the influence of the refractory and the slag on the mass transfer. A mathematical model coupled the ion and molecule coexistence theory, coupled-reaction model, and the surface renewal theory was established to predict the dynamic mass transfer and composition transformation of the steel, the slag, and nonmetallic inclusions in the steel. During the refining process,Al_(2)O_(3) inclusions transformed into Mg O inclusions owing to the mass transfer of [Mg] at the steel/refractory interface and(Mg O) at the slag/refractory interface. Most of the aluminum involved in the transport entered the slag and a small part of the aluminum transferred to lining refractory, forming the Al_(2)O_(3) or Mg O·Al_(2)O_(3). The slag had a significant acceleration effect on the mass transfer. The mass transfer rate(or the reaction rate) of the system with the slag was approximately 5 times larger than that of the system without the slag. In the first 20 min of the refining, rates of magnesium mass transfer at the steel/inclusion interface, steel/refractory interface, and steel/slag interface were x, 1.1 x, and 2.2 x,respectively. The composition transformation of inclusions and the mass transfer of magnesium and aluminum in the steel were predicted with an acceptable accuracy using the established kinetic model.

关键词： mass transfer steel slag lining refractory nonmetallic inclusions kinetic model

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Efficacy and safety of active silicone oil removal through a 23-gauge transconjunctival cannula using an external vacuum pump

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International Journal of Ophthalmology(English edition) 2015年第2期8卷 347-352页

作者： Hyun ju Oh Woohyok Chang min Sagong Department of Ophthalmology Yeungnam University College of Medicine

AIM: To evaluate the efficacy and safety of active removal of silicone oil with low and high viscosity through a 23-gauge transconjunctival cannula using an external vacuum ***: This study was conducted as a prospective, interventional case series. A total of 22 eyes of 21 patients [1000 centistokes(c St): 17 eyes, 5700 c St:5 eyes] were included in this study. All patients underwent active silicone oil removal via the entire lumen of a 23-gauge microcannula with suction pressure of a650-700 mm Hg vacuum using an external vacuum pump. A tubing adaptor from the Total Plus Pak誖(Alcon,Fort Worth, USA) was used to join the microcannula and silicone vacuum tube connected to an external vacuum pump. Main outcome measures were mean removal time,changes of intraocular pressure(IOP) and visual acuity,and intraoperative and postoperative ***: Mean removal time(min) was 1.49±0.43 for1000 c St and 7. 12 ± 1. 27 for 5700 c St. The IOP was18.57±7.48 mm Hg at baseline, 11.68 ±4.55 mm Hg at day1 postoperatively(P <0.001), and 15.95±4.92, 16.82±3.81,17.41 ±3.50, and 17.09 ±3.01 mm Hg after one week, one month, three months, and six months, respectively. All patients showed improved or stabilized visual *** was no occurrence of intraoperative or postoperative complications during the follow up ***: This technique for active removal of silicone oil through a 23-gauge cannula using an external vacuum pump is fast, effective, and safe as well as economical for silicone oil with both low and high viscosity in all eyes with pseudophakia, aphakia, or phakia.

关键词： active removal external vacuum pump silicone oil

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Application of Random Forest Regressions on Stellar Parameters of A-type Stars and Feature Extraction

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Research in Astronomy and Astrophysics 2022年第2期22卷 189-194页

作者： Shu-Xin Chen Wei-min Sun ying He Qiqihar University Qiqihar 161006China Key Lab of In-fiber Integrated Optics Ministry Education of ChinaHarbin Engineering UniversityHarbin 150009China Department of Computer Science and Technology Tianjin Ren'ai CollegeTianjin 301636China

Measuring the stellar parameters of A-type stars is more difficult than FGK stars because of the sparse features in their spectra and the degeneracy between effective temperature(T_(eff))and gravity(log g).Modeling the relationship between fundamental stellar parameters and features through machine learning is possible because we can employ the advantage of big data rather than sparse known *** soon as the model is successfully trained,it can be an efficient approach for predicting Teffand log g for A-type stars especially when there is large uncertainty in the continuum caused by flux calibration or *** this paper,A-type stars are selected from LAMOST DR7 with a signal-to-noise ratio greater than 50 and the Teffranging within 7000 to 10,000 *** perform the Random Forest(RF)algorithm,one of the most widely used machine learning algorithms to establish the regression relationship between the flux of all wavelengths and their corresponding stellar parameters(T_(eff))and(log g)*** trained RF model not only can regress the stellar parameters but also can obtain the rank of the wavelength based on their sensibility to *** to the rankings,we define line indices by merging adjacent *** objectively defined line indices in this work are amendments to Lick indices including some weak *** use the Support Vector Regression algorithm based on our new defined line indices to measure the temperature and gravity and use some common stars from Simbad to evaluate our *** addition,the Gaia Hertzsprung-Russell diagram is used for checking the accuracy of Teffand log g.

关键词： methods:data analysis surveys stars:early-type stars:abundances

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AN EXPERIMENTAL STUDY OF FLOW AROUND A BIO-INSPIRED AIRFOIL AT REYNOLDS NUMBER 2.0×10~3

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Journal of Hydrodynamics 2012年第3期24卷 410-419页

作者： SHI Sheng-xian LIU ying-zheng CHEN Jian-min Key Laboratory of Education ministry for Power Machinery and Engineering School of Mechanical EngineeringShanghai Jiao Tong University Shanghai 200240 China

The fluid flow around a bio-inspired airfoil with corrugated surfaces and its smooth counterpart at chord Reynolds number Re = 2.0×10^3. and different Angle-Of-Attack （AOA = 0°, 4°, 8° and 12°） were measured by using Particle Image Velocimetry （PIV）. The global characteristics of the fluid flow around two airfoils were analyzed by ensemble-averaged velocity field, distribution of reverse flow intermittency, and time-series flow visualizations. At AOA = 0°, no significant variation of the global flow patterns was recognized for both configurations. The statistical results of reverse flow intermittency results demonstrated that the protruding peaks of the corrugated airfoil delay flow separation occur at AOA = 4°. At large AOAs （8° and 12°）, however, the flow is massively separated in both configurations, the combination of large separation bubble above the corrugated airfoil and small recirculation zones in the upstream upper valley results in earlier separation of the flow. At AOA=8°, the wake region behind the corrugated airfoil is considerably shortened in comparison to the smooth one, indicating a remarkable reduction of the time-mean lift and drag forces, however, at AOA - 12°, the wake region behind the corrugated one is slightly larger than that behind the smooth one. For the case of AOA = 8° and 12°, the time-series flow visualizations demonstrate the intensified vortex shedding process of the corrugated airfoil, which would give rise to enhanced dynamic loading. Due to the fact that dragonfly wing is practically flexible, it is speculated that the wing structure of a gliding dragonfly might be sophisticatedly deformed in response to the periodic loading to reduce the drag.

关键词： corrugated airfoil separated flow Particle Image Velocimetry (PIV) dragonfly gliding flight

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Annotation of miRNAs in the COVID-19 Novel Coronavirus

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Journal of Electronic Science and Technology 2021年第1期19卷 6-13页

作者： Tie-ying Yu min Chen Chun-De Wang the Department of Yantai Institute of Coastal Zone Research and Center for Ocean Mega-Science Chinese Academy of SciencesYantai 264003 the College of Life Sciences Shandong Agricultural UniversityTai’an 271018 the School of Marine Science and Engineering Qingdao Agricultural UniversityQingdao 266109

The coronavirus disease 2019(COVID-19)coronavirus is a new strain of coronavirus that had not been previously detected in *** its severe pathogenicity is concerned,it is important to study it thoroughly to aid in the discovery of a *** this study,the microRNAs(miRNAs)of COVID-19 were annotated to provide a powerful tool for the study of this novel *** obtained 16 novel coronavirus genome sequences and the mature sequences of all viruses in the microRNA database(miRbase),and then used the miRNA matures sequences of the virus to perform the Basic Local Alignment Search Tool(BLAST)analysis in the coronavirus genome,extending the matched regions of approximately 20 bp to two segments by 200 *** sequences were obtained after deleting redundant ***,the hairpin structures of the mature miRNAs were determined using *** mature sequence on one hairpin arm was selected into a total of 4 sequences,and finally the relevant miRNA precursor prediction tools were used to verify whether the selected sequences are miRNA precursor sequences of the novel *** miRNAs of the novel coronavirus were annotated by our newly developed method,which will lay the foundation for further study of this virus.

关键词： microRNA(miRNAs)annotation novel coronavirus nucleotide Basic Local Alignment Search Tool(BLASTN) RNAfold

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Assignment of cis-Epoxides and Crystal Structure of cis-4-Nitro-N-(7-oxabicyclo[4.1.0]hept-2-yl)benzamide

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Chinese Journal of Structural Chemistry 2005年第8期24卷 945-951页

作者： HUANG Li ZHOU Ya-ju YE De-Yong CHEN min-Qin School of Pharrnacy Fudan University ChinaShanghai 200032 Department of Chemistry Fudan University ChinaShanghai 200433

The conformations and relative configurations of four epoxides of α-amido cyclohexenes have been determined by the combination of molecular modeling and NMR decoupling technique, cis-Epoxides were deduced from the vicinal coupling constants calculated from the torsional angles H（1）-C（1）-C（2）-H（2） in modeling models by means of Karplus equation and observed by decoupling technique. The crystal structure of cis-4-nitro-N-（7-oxabicyclo[4.1.0]hept-2-yl）benzamide further confirms this assignment.

关键词： epoxide molecular modeling, ^1H NMR stereochemistry

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Corrosion properties of high silicon iron-based alloys in nitric acid

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China Foundry 2007年第4期4卷 276-279页

作者： LI ju-cang WANG Shu-ying ZHAO Ai-min WANG Li-na LIU Feng-he University of Science and Technology Beijing Beijing 100083 China Jiuquan Iron and Steel （Group） Corporation Limited Jiayuguan 735100Gansu.China

The effect of copper and rare-earth elements on corrosion behavior of high silicon iron-based alloys in nitric acid was studied by means of static and loading current corrosion *** anodic polarization curve was also made to discuss the corrosion *** examination on alloy microstructure and SEM corrosion pattern showed that when silicon content reached 14.5%,the Fe3Si phase appeared and the primary structure of the iron-base alloy was *** adding 4.57% copper in the iron alloy,its corrosion resistance in static diluted sulfuric acid was improved while its corrosion resistance and electrochemical corrosion properties in the nitric acid were *** contrast,the addition of rare earth elements could improve the corrosion properties in all above conditions including in static diluted sulfuric acid and in nitric acid.

关键词： polarization curve corrosion resistance microstructure corrosion pattern iron-based alloys

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Distributions of dimethylsulfide in the Bohai Sea and Yellow Sea of China

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Journal of Environmental Sciences 2003年第6期15卷 762-767页

作者： HU min TANG Xiao-yan LI Jin-long MA Qi-ju State Joint Key Laboratory of Environmental Simulation and Pollution Control Center for Environmental Sciences Peking UniversityBeijing 100871China.

Dimethylsulfide(DMS) measurements in the surface seawater of China eastern coastline were conducted during March 9—10, 1993 in Bohai Sea along the cruise from Dalian to Tianjin and during September 24—25, 1994 in Yellow Sea along the cruise from Shanghai to Qingdao. On the cruise in Bohai Sea DMS concentrations varied from 0.11 to 2.63 nmol/L with an average of 1.31 nmol/L, while DMS flux was estimated to be 0.85 μmol/(m 2·d) with the range of 0.04—3.12 μmol/(m 2·d). On the cruise in Yellow Sea DMS concentrations varied from 0.95 to 7.48 nmol/L with an average of 2.89 nmol/L, and DMS flux was estimated to be 7.94 μmol/(m 2·d) with the range of 0.11—18.88 μmol/(m 2·d). Variations in DMS concentrations along the latitude in Yellow Sea were observed larger than those along the longitude in Bohai Sea. DMS concentrations and fluxes had a similar spatial trend both in Bohai Sea and Yellow Sea with the correlation coefficients of 0.75 and 0.64, respectively.

关键词： dimethylsulfide sea-to-air flux China Bohai Sea China Yellow Sea

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Uranyl photocatalysis:precisely controlled oxidation of sulfides with ground-state oxygen

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Science China Chemistry 2020年第3期63卷 291-293页

作者： Wei-min He ying-Wu Lin Dong-Hong Yu Department of Chemistry Hunan University of Science and EngineeringYongzhou 425100China Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation Changsha University of Science and TechnologyChangsha 410114China School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China Department of Chemistry and Bioscience Aalborg UniversityDK-9220 AalborgEastDenmark

Sulfur-containing organic compounds such as sulfides,sulfoxides and sulfones,have played significant roles in the fields of organic synthesis,pharmaceuticals,and *** selective oxidation of the parent sulfides has been... 详细信息

关键词： Uranyl oxidation ground-state oxygen

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