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Single incision laparoscopic fundoplication: A systematic review of the literature 预览
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作者 Konstantinos Perivoliotis Chamaidi Sarakatsianou +1 位作者 Konstantinos Tepetes Ioannis Baloyiannis 《世界胃肠外科杂志:英文版(电子版)》 2019年第3期179-190,共12页
BACKGROUND Fundoplication, was first introduced as a surgical treatment method of gastroesophageal reflux disease. Consequently, several modifications of this method have been described, whereas laparoscopic fundoplic... BACKGROUND Fundoplication, was first introduced as a surgical treatment method of gastroesophageal reflux disease. Consequently, several modifications of this method have been described, whereas laparoscopic fundoplication was recently introduced. Although single incision (SI) fundoplication was considered as an alternative to the conventional laparoscopic approach, several studies reported an increased operation duration, and high rates of multiport conversion and incisional hernia. AIM To provide a current overview of the technical variations and the postoperative outcomes of patients submitted to SI fundoplication. METHODS The present systematic review of the literature was designed and conducted on the basis of the PRISMA guidelines. A systematic screening of the electronic scholar databases (Medline, Scopus and Web of Science) was performed. RESULTS Literature search resulted in the identification of 19 studies. Overall, 266, 137 and 110 SI Nissen, Dor and Toupet fundoplications were reported, respectively. In the majority of the trials, standard laparoscopic instruments were used. The left liver lobe was displayed through the use of forceps, graspers, retractors, drains or even glue. Both intra-corporeal and extracorporeal suturing was described. Mean operative time was 136.3 min. Overall complication rate was 5.2% and the rate of incisional hernia was 0.9%. No mortality was reported.Due to the methodological heterogeneity and the lack of high quality studies comparing multi to single access techniques and the several variations, we conclude that further well designed studies are necessary, in order to evaluate the role of SI fundoplication. 展开更多
关键词 SINGLE INCISION SINGLE PORT FUNDOPLICATION NISSEN Dor TOUPET
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Single Crystal Growth and Magnetoresistivity of Topological Semimetal CoSi
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作者 吴德胜 米振宇 +6 位作者 李延杰 吴伟 李沛岭 宋友庭 刘广同 李岗 雒建林 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第7期77-81,共5页
We report single crystal growth of CoSi, which has recently been recognized as a new type of topological semimetal hosting fourfold and sixfold degenerate nodes. The Shubnikov–de Haas quantum oscillation(QO) is obser... We report single crystal growth of CoSi, which has recently been recognized as a new type of topological semimetal hosting fourfold and sixfold degenerate nodes. The Shubnikov–de Haas quantum oscillation(QO) is observed on our crystals. There are two frequencies originating from almost isotropic bulk electron Fermi surfaces, in accordance with band structure calculations. The effective mass, scattering rate, and QO phase difference of the two frequencies are extracted and discussed. 展开更多
关键词 SINGLE CRYSTAL GROWTH been recognized as extracted and discussed
单次或多次血液灌流对重度有机磷农药中毒的疗效比较
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作者 王陡 岳亚杰 +1 位作者 宋克义 颜秀侠 《中华全科医学》 2019年第9期1495-1497,1599共4页
目的比较血液灌流(HP)次数对重度急性有机磷农药中毒患者的临床疗效。方法回顾性分析2014年1月-2018年7月安徽理工大学附属亳州市人民医院收治的86例急性重度有机磷农药中毒患者,根据HP治疗次数分为对照组(HP 0次,26例),HP单次组(HP 1次... 目的比较血液灌流(HP)次数对重度急性有机磷农药中毒患者的临床疗效。方法回顾性分析2014年1月-2018年7月安徽理工大学附属亳州市人民医院收治的86例急性重度有机磷农药中毒患者,根据HP治疗次数分为对照组(HP 0次,26例),HP单次组(HP 1次,31例),HP多次组(HP≥2次,29例)。比较3组患者长托宁和解磷定总用量,血清胆碱酯酶活性恢复80%时间(h1)、昏迷时间(h2)、住院时间(h3)、机械通气时间(h4)及中间综合征、中毒反跳、心律失常、多器官功能障碍综合征发生率、病死率。结果对照组、HP单次组、HP多次组长托宁总量[(38.28±11.33)mg、(25.62±9.57)mg、(16.54±9.45)mg]和解磷定总量[(22.35±5.45)mg、(16.53±3.64)mg、(10.22±2.45)mg]依次减少(均P<0.05),h1[(15.32±3.42)h,(10.26±2.04)h,(7.32±3.64)h],h2[(96.23±8.22)h,(46.28±7.69)h,(28.56±7.21)h],h3[(18.21±3.22)d,(13.52±3.64)d,(8.23±2.33)d]、h4[(136.42±18.68)h,(92.46±16.28)h,(47.28±15.42)h]依次缩短(均P<0.05),入院72 h APACHE-Ⅱ评分(18.23±4.12,15.25±3.06,12.52±2.08)依次降低(P<0.05)。HP多次组中间综合征、反跳、MODS发生例数少于对照组和HP单次组,差异具统计学意义(均P<0.05)。HP多次组和HP单次组心律失常例数均少于对照组(均P<0.05)。病死数构成3组间差异无统计学意义(P>0.05)。结论重度有机磷中毒患者多次行血液灌流临床治疗效果可,并发症少。 展开更多
关键词 单次 多次 血液灌流 重度中毒 疗效
Conformationally Dynamic Supramolecular Single Chain Nanogels for Mutilscale Biomechanical Regulation of Stem Cells
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作者 Liming Bian 《医用生物力学》 CAS CSCD 北大核心 2019年第A01期150-151,共2页
Objective The binding of cell adhesive peptides(such as RGD)to integrins initiates the recruitment of cytoplasmic adaptor proteins(e.g.,vinculin)and the formation of focal adhesion(FA)complexes required for cell adhes... Objective The binding of cell adhesive peptides(such as RGD)to integrins initiates the recruitment of cytoplasmic adaptor proteins(e.g.,vinculin)and the formation of focal adhesion(FA)complexes required for cell adhesion.The ability to manipulate this ligand-mediated cell adhesion process is crucial for regulating cell migration,cell differentiation,injury healing,and immune response.Some recent studies reported the importance of the tether length/mobility of the cell adhesive ligands in regulating the traction force development of cells.In the native cellular microenvironment,such a dynamic change in the nanoscale tether length of bioactive ligands is often mediated by conformational changes of the structural proteins due to protein folding or degradation.However,no prior studies have demonstrated the modulation of the ligand tether mobility by controlling the intramolecular folding of polymeric linkers.Unfoldable synthetic macromolecules with easy synthetic routes and controllable structures,such as supramolecular host-guest single chain nanogels(SCNGs),are ideal candidates for mimicking the changes in the tether mobility of bioactive ligands via biorthogonal triggers.Methods S,S’-bis(a’a’-dimethyl-a’’-propargyl acetate)trithiocarbonate was first used to mediate the RAFT polymerization of N,N-dimethyl acrylamide,vinyl-adamantane and vinyl-β-cyclodextrin to yield the ADA@CD-SCNGs.The preparation of the unfoldable host-guest SCNGs was evidenced by the by gel permeation chromatography,proton nuclear magnetic resonance spectroscopy,atomic force microscopy and dynamic light scattering.Then the RGD peptide was conjugated to the alkynyl group on one end of the SCNGs before immobilizing the material on the substrate,which was confirmed by scanning electron microscopy(SEM).The regulation of cell behaviours by unfolding of the SCNG-RGD was confirmed by immunofluorescence staining of vinculin and Yes-associated protein(YAP).Results The preparation of ADA@CD-SCNGs was confirmed by GPC which showed a unimodal mol 展开更多
关键词 Single CHAIN NANOGELS Mutilscale BIOMECHANICAL REGULATION STEM Cells
Application of Fingerprint Combined with QAMS in Quality Evaluation of Zhenrongdan Mixture 预览
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作者 Jianping ZHANG Dong WANG Xuemei ZHOU 《药用植物研究(英文版)》 2019年第2期50-53,共4页
[Objectives] The research aimed to evaluate the quality of Zhenrongdan mixture by fingerprint combining QAMS.[Methods] The quality evaluation method was established and validated with echinacoside as internal referenc... [Objectives] The research aimed to evaluate the quality of Zhenrongdan mixture by fingerprint combining QAMS.[Methods] The quality evaluation method was established and validated with echinacoside as internal reference to determine the contents of other components(ferulic acid, salvianolic acid B, and icariin) according to the relative correction factor. The accuracy and feasibility of QAMS were evaluated by comparison on the results between the measured value and calculation value by external standard method and QAMS.[Results] A common pattern of characteristic fingerprint of Zhenrongdan mixture by HPLC was established. Thirteen common peaks were identified, and they account for 91% of the total peak area, and four components were verified in five batches of Zhenrongdan mixture. Good similarities with correlation coefficients higher than 0.99 were found in the fingerprints. There was no significant difference between the quantitative results of the four ingredients in the five batches by external standard method and QAMS.[Conclusions] The method of fingerprint combined with QAMS could be used for the quality control of multiple components determination and fingerprint chromatography for Zhenrongdan mixture. 展开更多
关键词 FINGERPRINT QUANTITATIVE analysis of multi-components by single MARKER (QAMS) Zhenrongdan MIXTURE Quality control CORRECTION FACTOR
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Evolution of interfacial dislocation networks during long term thermal aging in Ni-based single crystal superalloy DD5
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作者 Qiang Gao Li-rong Liu +3 位作者 Xiao-hua Tang Zhi-jiang Peng Ming-jun Zhang Su-gui Tian 《中国铸造:英文版》 SCIE 2019年第1期14-22,共9页
Interfacial dislocations found in single crystal superalloys after long term thermal aging have an important effect on mechanical properties. Long term thermal aging tests for DD5 single crystal superalloy were carrie... Interfacial dislocations found in single crystal superalloys after long term thermal aging have an important effect on mechanical properties. Long term thermal aging tests for DD5 single crystal superalloy were carried out at 1,100 ℃ for 20, 100, 200, 500 and 1000 h, and then cooled by air. The effect of long term thermal aging on the dislocation networks at the γ/γ’ interfaces was investigated by FE-SEM. Results showed that during the long term thermal aging at 1,100 ℃, misfit dislocations formed firstly and then reorientation in the(001) interfacial planes occurred. Different types of square or rectangular dislocation network form by dislocation reaction. Square dislocation networks consisting of four groups of dislocations can transform into octagonal dislocation networks, and then form another square dislocation network by dislocation reaction. Rectangular dislocation networks can also transform into hexagonal dislocation networks. The interfacial dislocation networks promote the γ’ phase rafting process. The dislocation networks spacings become smaller and smaller, leading to the effective lattice misfit increasing from-0.10% to-0.32%. 展开更多
关键词 DD5 single crystal SUPERALLOY INTERFACIAL dislocations long TERM thermal AGING effective LATTICE MISFIT
Phosphorene: Current status, challenges and opportunities
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作者 Anandarup Goswami Manoj B.Gawande 《化学科学与工程前沿:英文版》 EI CAS CSCD 2019年第2期296-309,共14页
The field of 2-dimensional (2D) materials has witnessed a sharp growth since its inception and can majorly be attributed to the substantial technical and scientific developments, leading to significant improvements in... The field of 2-dimensional (2D) materials has witnessed a sharp growth since its inception and can majorly be attributed to the substantial technical and scientific developments, leading to significant improvements in their syntheses, characterization and applications. In the list of 2D materials, the relatively newer addition is phosphorene, which ideally consists of a single layer of black phosphorous. Keeping in mind the past, and ongoing research activities, this short account offers a brief overview of the present status and the associated challenges in the field of phosphorene-related research, with special emphasis on their syntheses, properties, applications and future opportunities. 展开更多
关键词 phosphorene black phosphorous ANISOTROPY single layer THERMOELECTRIC chemical vapor DEPOSITION CATALYSIS BATTERY SUPERCAPACITOR
Telecom wavelength single photon sources 预览
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作者 Xin Cao Michael Zopf Fei Ding 《半导体学报:英文版》 EI CAS CSCD 2019年第7期16-26,共11页
Single photon sources are key components for quantum technologies such as quantum communication, computing and metrology. A key challenge towards the realization of global quantum networks are transmission losses in o... Single photon sources are key components for quantum technologies such as quantum communication, computing and metrology. A key challenge towards the realization of global quantum networks are transmission losses in optical fibers. Therefore, single photon sources are required to emit at the low-loss telecom wavelength bands. However, an ideal telecom wavelength single photon source has yet to be discovered. Here, we review the recent progress in realizing such sources. We start with single photon emission based on atomic ensembles and spontaneous parametric down conversion, and then focus on solid-state emitters including semiconductor quantum dots, defects in silicon carbide and carbon nanotubes. In conclusion, some state-of-the-art applications are highlighted. 展开更多
关键词 TELECOM WAVELENGTH single PHOTON SOURCES QUANTUM COMMUNICATION
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Single and double aging treatments on Mg97Zn1Y2 alloy
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作者 Di-qing Wan Ying-lin Hu +1 位作者 Hou-bin Wang Shu-ting Ye 《中国铸造:英文版》 SCIE 2019年第1期46-52,共7页
The development of magnesium alloys was limited due to the low absolute strength and poor corrosion resistance. It was found that the optimal performance could not be achieved in some alloys by a single quenching and ... The development of magnesium alloys was limited due to the low absolute strength and poor corrosion resistance. It was found that the optimal performance could not be achieved in some alloys by a single quenching and aging treatment, but could be achieved after a graded aging or multiple-stage aging heat treatment. The Mg97Zn1Y2 alloy was prepared and subjected to single and double aging treatments. Single aging was carried out at 250 ℃ for 6 to 15 h. For double aging, the first step was performed the same as the single aging. The second step was performed at 350 ℃ for 12 h. The microstructure and properties of the alloy with single and double aging were analyzed by means of hardness measurement, optical microscopy, scanning electron microscopy, X-ray diffraction, and polarization curve measurements. Results show that the precipitated nanoscale phases are formed during aging, and evenly distributed in the matrix. Compared with the single aging treatment, the hardness and corrosion resistance of the alloy are further improved due to the double aging treatment. 展开更多
关键词 SINGLE AGING DOUBLE AGING Mg97Zn1Y2 ALLOY LPSO PHASE
Review on the quantum emitters in two-dimensional materials 预览
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作者 Shuliang Ren Qinghai Tan Jun Zhang 《半导体学报:英文版》 EI CAS CSCD 2019年第7期38-45,共8页
The solid state single photon source is fundamental key device for application of quantum communication, quantum computing, quantum information and quantum precious metrology. After years of searching, researchers hav... The solid state single photon source is fundamental key device for application of quantum communication, quantum computing, quantum information and quantum precious metrology. After years of searching, researchers have found the single photon emitters in zero-dimensional quantum dots (QDs), one-dimensional nanowires, three-dimensional wide bandgap materials, as well as two-dimensional (2D) materials developed recently. Here we will give a brief review on the single photon emitters in 2D van der Waals materials. We will firstly introduce the quantum emitters from various 2D materials and their characteristics. Then we will introduce the electrically driven quantum light in the transition metal dichalcogenides (TMDs)-based light emitting diode (LED). In addition, we will introduce how to tailor the quantum emitters by nanopillars and strain engineering, the entanglement between chiral phonons (CPs) and single photon in monolayer TMDs. Finally, we will give a perspective on the opportunities and challenges of 2D materials-based quantum light sources. 展开更多
关键词 TWO-DIMENSIONAL MATERIALS single PHOTON source QUANTUM ENTANGLEMENT
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An investigation. antibacterial effects Nd:YAG Laser. Porphyromonas gingivalis 预览
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作者 Pengyu Ji 《探索-牙科学》 2019年第1期6-8,共3页
AIM:. Investigate. antibacterial effects Nd:YAG laser. Porphyromonas gingivalisFilm, deconstruction. becterium became distincted. iradiation time increased.. Major destructional form. evaporation.Conclusion:Nd:YAG las... AIM:. Investigate. antibacterial effects Nd:YAG laser. Porphyromonas gingivalisFilm, deconstruction. becterium became distincted. iradiation time increased.. Major destructional form. evaporation.Conclusion:Nd:YAG laser may inhibit. biofilm formation. planktonic P.Gingivalis, destroy. construction. mature biofilm, Bacteria. 展开更多
关键词 PERIODONTAL PATHOGENS SINGLE BACTERIA BIOFILM ND:YAG
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Electrically driven single-photon sources 预览
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作者 Yating Lin Yongzheng Ye Wei Fang 《半导体学报:英文版》 EI CAS CSCD 2019年第7期46-54,共9页
Single-photon sources are building blocks for photonic quantum information processes. Of the many single-photon generation schemes, electrically driven single-photon sources have the advantages of realizing monolithic... Single-photon sources are building blocks for photonic quantum information processes. Of the many single-photon generation schemes, electrically driven single-photon sources have the advantages of realizing monolithic integration of quantum light sources and detectors without optical filtering, thus greatly simplify the integrated quantum photonic circuits. Here, we review recent advances on electrically driven single-photon sources based on solid-state quantum emitters, such as semiconductor epitaxial quantum dots, colloidal quantum dots, carbon nanotubes, molecules, and defect states in diamond, SiC and layered semiconductors. In particular, the merits and drawbacks of each system are discussed. Finally, the article is concluded by discussing the challenges that remain for electrically driven single-photon sources. 展开更多
关键词 SINGLE PHOTON SOURCES electrically DRIVEN INTEGRATED QUANTUM photoncs
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Ⅲ–Ⅴ compounds as single photon emitters 预览
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作者 Xu Wang Lei Xu +4 位作者 Yun Jiang Zhouyang Yin Christopher C. S. Chan Chaoyong Deng Robert A. Taylor 《半导体学报:英文版》 EI CAS CSCD 2019年第7期63-74,共12页
Single-photon emitters (SPEs) are one of the key components in quantum information applications. The ideal SPEs emit a single photon or a photon-pair on demand, with high purity and distinguishability. SPEs can also b... Single-photon emitters (SPEs) are one of the key components in quantum information applications. The ideal SPEs emit a single photon or a photon-pair on demand, with high purity and distinguishability. SPEs can also be integrated in photonic circuits for scalable quantum communication and quantum computer systems. Quantum dots made from Ⅲ-Ⅴ compounds such as InGaAs or GaN have been found to be particularly attractive SPE sources due to their well studied optical performance and state of the art industrial flexibility in fabrication and integration. Here, we review the optical and optoelectronic properties and growth methods of general SPEs. Subsequently, a brief summary of the latest advantages in Ⅲ-Ⅴ compound SPEs and the research progress achieved in the past few years will be discussed. We finally describe frontier challenges and conclude with the latest SPE fabrication science and technology that can open new possibilities for quantum information applications. 展开更多
关键词 single PHOTON EMITTERS solid-states QUANTUM DOTS 2D materials
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Research on SEE mitigation techniques using back junction and p~+ buffer layer in domestic non-DTI SiGe HBTs by TCAD
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作者 魏佳男 贺朝会 +1 位作者 李培 李永宏 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期465-471,共7页
In this paper we investigate two techniques for single event effect(SEE) mitigation by using back junction and p~+buffer layer in non-deep trench isolation(DTI) domestic silicon–germanium heterojunction bipolar trans... In this paper we investigate two techniques for single event effect(SEE) mitigation by using back junction and p~+buffer layer in non-deep trench isolation(DTI) domestic silicon–germanium heterojunction bipolar transistors(SiGe HBTs)based on technology computer aided design(TCAD) simulation. The effectiveness of the two mitigation techniques and the influence of various structure parameters are investigated. Simulation results indicate that the two techniques are more effective in reducing collector charge collection induced by heavy ions striking at positions outside the collector–substrate(C–S) junction where charge collection is dominated by diffusion. By properly adjusting the parameters, charge collection of events outside the C–S junction can be reduced by more than an order of magnitude, while charge collection of events in the device center is halved without affecting the direct current(DC) and alternating current(AC) characteristics of the SiGe HBTs. 展开更多
关键词 silicon–germanium HBT single event effect MITIGATION technique TCAD simulation
Insight of the stability and activity of platinum single atoms on ceria
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作者 Xuxu Ye Hengwei Wang +4 位作者 Yue Lin Xinyu Liu Lina Cao Jian Gu Junling Lu 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第6期1401-1409,共9页
Single-atom catalysts (SACs) have recently attracted broad attention in the catalysis field due to their maximized atom efficiency and unique catalytic properties.An atomic-level understanding of the interaction betwe... Single-atom catalysts (SACs) have recently attracted broad attention in the catalysis field due to their maximized atom efficiency and unique catalytic properties.An atomic-level understanding of the interaction between the metal atoms and support is vital for developing stable and high-performance SACs.In this work,Pt1 single atoms with Ioadings up to 4 wt.% were fabricated on ceria nanorods using the atomic layer deposition technique.To understand the Pt-O-Ce bond interfacial interactions,the stability of Pt1 single atoms in the hydrogen reducing environment was extensively investigated by using in situ diffuse reflectance infrared Fourier transform spectroscopy CO chemisorption measurements.It was found that ceria defect sites,metal Ioadings and high-temperature calcination are effective ways to tune the stability of Pt1 single atoms in the hydrogen environment.X-ray photoemission spectroscopy further showed that Pt1 single atoms on ceria are dominantly at a +2 valence state at the defect and step edge sites,while those on terrace sites are at a +4 state.The above tailored stability and electronic properties of Pt1 single atoms are found to be strongly correlated with the catalytic activity in the dry and water-mediated CO oxidation reactions. 展开更多
关键词 single ATOM catalyst Pt1/CeO2 metal-support interaction stabilitywater-mediated CO OXIDATION
SSCC:A Novel Computational Framework for Rapid and Accurate Clustering Large-scale Single Cell RNA-seq Data
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作者 Xianwen Ren Liangtao Zheng Zemin Zhang 《基因组蛋白质组与生物信息学报:英文版》 CAS CSCD 2019年第2期201-210,共10页
Clustering is a prevalent analytical means to analyze single cell RNA sequencing (scRNA-seq) data but the rapidly expanding data volume can make this process computationally challenging. New methods for both accurate ... Clustering is a prevalent analytical means to analyze single cell RNA sequencing (scRNA-seq) data but the rapidly expanding data volume can make this process computationally challenging. New methods for both accurate and efficient clustering are of pressing need. Here we proposed Spearman subsampling-clustering-classification (SSCC),a new clustering framework based on random projection and feature construction,for large-scale scRNA-seq data. SSCC greatly improves clustering accuracy,robustness,and computational efficacy for various state-of-the-art algorithms benchmarked on multiple real datasets. On a dataset with 68,578 human blood cells,SSCC achieved 20%improvement for clustering accuracy and 50-fold acceleration,but only consumed 66%memory usage,compared to the widelyused software package SC3. Compared to k-means,the accuracy improvement of SSCC can reach 3-fold. An R implementation of SSCC is available at https://github.com/Japrin/sscClust. 展开更多
关键词 Single cell RNA-SEQ CLUSTERING SUBSAMPLING Classification
How long a C–C bond can be? An example of extraordinary long C–C single bond in 1,2-diarylamino-o-carborane
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作者 Yile Wu Jie Zhang Zuowei Xie 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第8期1530-1532,共3页
How long a C-C bond can be?A question has long fascinated chemists.This work reports an example of extraordinary long C-C bond distance of 1.990(4)?observed in single-crystal X-ray structure of 1,2-(NHMes)2-o-carboran... How long a C-C bond can be?A question has long fascinated chemists.This work reports an example of extraordinary long C-C bond distance of 1.990(4)?observed in single-crystal X-ray structure of 1,2-(NHMes)2-o-carborane(2;Mes=2,4,6-trimethylphenyl).DFT calculations show that hyperconjugation of lone pairs of the nitrogen atoms into the emptyσ^*orbital of the cage C-C bond is the origin of the bond elongation.Such hyperconjugation can be suppressed if the two nitrogen atoms in 2 are linked to a Lewis acidic germanium(Ⅱ)center. 展开更多
关键词 O-CARBORANE C–C single bond Hyperconjugation AMINE X-ray structure
Study on Characteristics of Underground Horizontal Electric Field Caused by Lightning Return Stroke Based on FDTD Method 预览
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作者 Zhao Liang Gu Lili +1 位作者 Hao Ling Liu Ruixiang 《气象与环境研究:英文版》 CAS 2019年第1期39-42,共4页
Based on the MTLL lightning return stroke model, a two-dimensional cylindrical finite-difference time-domain (FDTD) model for underground horizontal electric field was established, and the effects of distance from lig... Based on the MTLL lightning return stroke model, a two-dimensional cylindrical finite-difference time-domain (FDTD) model for underground horizontal electric field was established, and the effects of distance from lightning channel, depth, soil electrical conductivity and its distribution, and return stroke current on the characteristics of underground horizontal electric field were analyzed. The results showed that as long as the electrical conductivity of soil existed, the peak of underground horizontal electric field decreased with the increase in the horizontal distance from lightning channel. When the electrical conductivity of the upper soil was much smaller than that of the lower soil, the peak of corresponding horizontal electric field was larger than the electric field peak as the electrical conductivity of the upper soil was larger than that of the lower soil. When the electrical conductivity of the upper soil was less than that of the lower soil, the growth and decay of the horizontal electric field were faster than the growth and decay as the electrical conductivity of the upper soil was larger than that of the lower soil. 展开更多
关键词 UNDERGROUND HORIZONTAL electric field LIGHTNING RETURN stroke FDTD Single layer soil LAYERED
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Optimization of Candida tropicalis Fermentation Conditions to Produce Long-chain Dibasic Acids 预览
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作者 Xiang XIU Junqing WANG 《农业生物技术:英文版》 CAS 2019年第2期160-164,共5页
[Objectives] The fermentation conditions of Candida tropicalis 1798- pxa 1 were optimized to further improve its yield of long-chain dibasic acids.[Methods] The strains used in the study were C. tropicalis 1798, C. tr... [Objectives] The fermentation conditions of Candida tropicalis 1798- pxa 1 were optimized to further improve its yield of long-chain dibasic acids.[Methods] The strains used in the study were C. tropicalis 1798, C. tropicalis 1798- pxa 1 and C. tropicalis 1798- pxa1p2 . First, through single factor experiments, the activated three fungi were cultured in different carbon sources, and the absorbance was measured every 2h. The growth curve was drawn by software, and finally the most suitable substance for the substrate was selected, i.e., dodecane. Then, the composition of the fermentation medium and the fermentation process parameters were determined through the PB experiment of the single-deletion C. tropicalis 1798- pxa1 .[Results] The experiment determined the important components affecting the synthesis of long-chain dibasic acids, namely (NH4)2SO4, NaCl and dodecane. After optimization of the culture conditions, the yield of long-chain dibasic acids of C. tropicalis 1798- pxa1 increased from 5.6 to 10.1 g/L.[Conclusions] The scheme has been verified to be capable of greatly increasing the yield of the corresponding long-chain dibasic acids of the C. tropicalis engineering strain. 展开更多
关键词 Synthesis of LONG-CHAIN dibasic acid CANDIDA TROPICALIS engineering FUNGUS Single factor EXPERIMENT PB EXPERIMENT Condition OPTIMIZATION
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CFD and experimental investigations on the micromixing performance of single countercurrent-flow microchannel reactor
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作者 Kunpeng Cheng Chunyu Liu +1 位作者 Tianyu Guo Lixiong Wen 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第5期1079-1088,共10页
Microchannel reactors are widely used in different fields due to their intensive micromixing and, thus, high masstransfer efficiency. In this work, a single countercurrent-flow microchannel reactor(S-CFMCR) at the siz... Microchannel reactors are widely used in different fields due to their intensive micromixing and, thus, high masstransfer efficiency. In this work, a single countercurrent-flow microchannel reactor(S-CFMCR) at the size of ~1 mm was developed by steel micro-capillary and laser drilling technology. Utilizing the Villermaux/Dushman parallel competing reaction, numerical and experimental studies were carried out to investigate the micromixing performance(expressed as the segregation index XS) of liquids inside S-CFMCR at the low flow velocity regime.The effects of various operating conditions and design parameters of S-CFMCR, e.g., inlet Reynolds number(Re),volumetric flow ratio(R), inlet diameter(d) and outlet length(L), on the quality of micromixing were studied qualitatively. It was found that the micromixing efficiency was enhanced with increasing Re, but weakened with the increase of R. Moreover, d and L also have a significant influence on micromixing. CFD results were in good agreement with experimental data. In addition, the visualization of velocity magnitude, turbulent kinetic energy and concentration distributions of various ions inside S-CFMCR was illustrated as well. Based on the incorporation model, the estimated minimum micromixing time tmof S-CFMCR is ~2 × 10-4s. 展开更多
关键词 SINGLE countercurrent-flow MICROCHANNEL REACTOR MICROMIXING performance CFD Villermaux/Dushman reaction
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