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Application of Multi-echo in steady-state acquisition sequence in MR imaging of Inferior alveolar nerve

中华口腔医学会口腔颌面放射专业委员会第21次全国学术会...

作者： Qi Sun MINJUN DONG Department of Radiology Shanghai Ninth People’s Hospital Shanghai Jiao Tong University School of Medicine

According to the literature, there is no reliable and quantitative method available for the diagnosis and prognosis of early or potential temporomandibular joint (TMJ) condylar resorption (CR) thus far. The purpose of this study was to raise a new noninvasive method to quantitatively evaluate condylar quality using the signal intensity ratio (SIR) on magnetic resonance imaging (MRI) in order to assist in the diagnosis of TMJ CR.

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Application of Multi-echo in steady-state acquisition sequen...

基于介孔二氧化硅纳米粒子的成像介导多功能诊疗纳米体系用于癌症的治疗

中华口腔医学会口腔颌面放射专业委员会第21次全国学术会...

作者： Qi Sun MINJUN DONG Department of Radiology Shanghai Ninth People’s Hospital Shanghai Jiao Tong University School of Medicine

Purpose This study evaluated the performance of a 4-min multi-echo in steady-state acquisition(MENSA) sequence in MRI for the assessment of Inferior alveolar nerve.Methods 15 subjects underwent MENSA sequence on a 3.0-T MRI scanner. Two Oral and Maxillofacial Surgery doctor and radiologist independently assessed the images for quality and diagnostic capability. A qualitative assessment scoring system for image quality and quantitative nerve signal-to-noise ratio(SNR) and inferior alveolar nerve and masseter muscle contrast-to-noise ratios(CNR) was applied. Using surgical reports as the reference, sensitivity, specifcity, accuracy, and area under the receiver operating characteristic curves(AUC) were evaluated. Intraclass correlation coefcients(ICC) and weighted kappa were used to calculate reliability.Results Weighted kappa and ICC values indicated good reliability. Sensitivity, specifcity, and accuracy of diagnosis based on MENSA images were 96.23%, 89.47%, and 94.44%, respectively, and AUC was 0.929. Weighted kappa values for intraobserver(0.758) and interobserver(0.768–0.818) reliability were substantial to perfect.Conclusion A time-efcient 4-min MENSA protocol exhibits superior image quality and high vascular contrast with the potential to produce high-resolution inferior alveolar nerve images.

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基于介孔二氧化硅纳米粒子的成像介导多功能诊疗纳米体系用于癌症...

作者： Qi Sun 天津大学

学位级别：硕士

一直以来,癌症是困扰人们的一项重大疾病,一些传统治疗方式给患者带来巨大痛苦的同时,治疗效果也并非理想。随着20世纪70年代纳米概念的首次提出,纳米生物技术也应运而生。近些年来,纳米技术对恶性肿瘤的治疗研究层出不穷,俨然,纳米技... 详细信息

一直以来,癌症是困扰人们的一项重大疾病,一些传统治疗方式给患者带来巨大痛苦的同时,治疗效果也并非理想。随着20世纪70年代纳米概念的首次提出,纳米生物技术也应运而生。近些年来,纳米技术对恶性肿瘤的治疗研究层出不穷,俨然,纳米技术已经成为癌症治疗领域的一个重要的方向。其中,介孔二氧化硅纳米棒(mesoporous silica nanorods,MSNRs)与磷脂双分子层包被的介孔二氧化硅纳米粒,由于其具有更加良好的细胞摄取率,较高的载药特性和优良的生物相容性,在纳米载体领域受到广泛地研究与探索。此外,纳米诊疗学在纳米技术的基础上更是急速地发展,应用于癌症的诊断与治疗当中。将荧光成像剂、光声成像造影剂和核磁成像造影剂等载入或掺杂到纳米载体当中,有针对性地递送到病变组织部位,可进一步对恶性肿瘤的定位与诊断,以此实现癌症治疗的诊断与治疗的一体化研究。这种复合纳米载体,由于其多功能性,在如今的癌症治疗研究领域受到人们广泛地关注与研究,为癌症的治疗带来新的机遇。除此之外,超越传统的手术治疗、化学疗法和放射疗法等对恶性肿瘤的治疗,光动力学治疗(photodynamic therapy,PDT)与光热治疗(photothermal therapy,PTT)具有较高的选择性,可减少对正常组织的损伤等优点,经常被赋予在纳米载体对癌症的治疗当中。值得一提的是,光动力治疗和光热治疗的联合应用,可以克服相互的缺点,以此克服癌症治疗中的多种局限性,在对抗肿瘤的实验研究中,发挥着积极的作用,也具有极大的临床应用前景。首先,本论文报道了金纳米棒包覆的光敏剂二氢卟吩e6掺杂的介孔二氧化硅纳米棒(AuNRs-Ce6-MSNRs),在660 nm单近红外光(single-NIR light)的触发下,应用于癌症的联合治疗方法。其中,二氢卟吩e6(Chlorin e6,Ce6)作为新型的光敏剂,大量的实验研究显示,Ce6具有较高的单线态氧产率,较长的吸收波长,可以作为荧光成像追踪剂,以及代谢迅速等诸多优点,被广泛地应用在光动力学治疗领域。在光热治疗方面,金纳米粒子(Au nanoparticles,AuNPs)具有表面等离子共振(surface plasmon resonance,SPR)现象,具有良好的光热治疗效果,同时还可以作为造影剂用于光声成像。金纳米棒(Au nanorods,AuNRs)除了继承了一般的球形金纳米粒子的优点,还具有更高的光热能量转化效率,更大的表面积以及更易于被细胞摄取等优点,在光热治疗领域受到极大的重视与青睐。AuNRs-Ce6-MSNRs由于光热剂AuNRs的产热性能,可以发挥光热治疗作用。在未给予单近红外光的激发时,AuNRs与Ce6相接触,使Ce6暂时淬灭;给予近红外光激发后,AuNRs脱离主载体,光敏剂Ce6解淬灭,从而产生更多的单线态氧(O),从而致力于光动力学的治疗。这种光动力学与光热的联合治疗方式,不仅可以提高了抗癌效果,同时由于AuNRs和Ce6的存在,此载体系统兼具有光声成像(photoacoustic,PA)和近红外荧光成像(NIR fluorescence,NIRF)的特性。本设计当中,Ce6的投入量可以控制介孔二氧化硅纳米粒的形态,通过探索,我们最终确定了最优投入量,使得一定长径比的介孔二氧化硅纳米棒的形成。除此之外,Ce6通过供价连接的作用,与介孔二氧化硅纳米棒牢固结合,可以不经过释放即发挥光动力学治疗的作用,以此来解决药物到达靶标提前泄漏的问题。介孔二氧化硅纳米粒(mesoporous silica nanoparticles,MSNs)作为一种多功能药物载体,具有较大的表面积,可调节的孔径,易于修饰和生物相容性强等优良的特性,早已被广泛地投入到载体领域的研究当中,并且广泛地应用于生物医学领域的研究当中。值得一提的是,作为纳米载体,本论文中所述的介孔二氧化硅纳米棒状的特殊结构,相比较普通的球状介孔二氧化硅纳米粒,具有高的载药量,并且能提高细胞摄取效率。综上,此多功能纳米复合材料,整合了光热治疗和光动力学治疗,和体内荧光与光声的二元成像功能于同一纳米载药系统,在体外与体内抗肿瘤的联合治疗效果显示皆良好。经过对成功制备的AuNRs-Ce6-MSNRs进行表征,透射电镜结果显示,Ce6-MSNRs纳米载体粒径在200 nm左右,呈现长径比较小的棒状结构,孔道结构较有规律,孔径大小适中。AuNRs吸附在Ce6-MSNRs表面,形成统一的纳米载体。经过紫外可见分光光度计的检测,AuNRs-Ce6-MSNRs同时具有Ce6和AuNRs的紫外吸收峰,说明两者均被成功载入到介孔二氧化硅纳米棒载体当中。通过红外光谱的检测,经过长时间冷凝回流,模版被成功去除,以此形成AuNRs-Ce6-MSNRs的有序孔道。体外升温实验证明,AuNRs-Ce6-MSNRs的水分散液在660 nm近红外光源的激发下,5分钟内,温度可以升高将

关键词：介孔硅纳米棒钆介孔硅纳米粒热敏脂质体光动力学治疗光热治疗多模态成像

A process study of high-quality Zn(O,S)thin-film fabrication for thin-film solar cells

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Clean Energy 2023年第2期7卷 283-292页

作者： Qi Sun Boyan Li Xingye Huang Zhihua Han Dalong Zhong Ying Zhao National Institute of Clean-and-Low-Carbon Energy PO Box 001 Shenhua NICEFuture Science&Technology CityChangping DistrictBeijing 102211P.R.China Beijing Engineering Research Center of Nano-structured Thin Film Solar Cells Beijing 102209P.R.China

The Zn(O,S)thin film is considered a most promising candidate for a cadmium-free buffer layer of the Cu(In,Ga)Se_(2)(CIGS)thin-film solar cell due to its advantages of optical responses in the short-wavelength region and adjustable bandgap.In this paper,the thin-film growth mechanism and process optimization of Zn(O,S)films fabricated using the chemical bath deposition method are sys-tematically investigated.The thickness and quality of Zn(O,S)films were found to be strongly affected by the concentration variation of the precursor chemicals.It was also revealed that different surface morphologies of Zn(O,S)films would appear if the reaction time were changed and,subsequently,the optimum reaction time was defined.The film-growth curve suggested that the growth rate varied linearly with the deposition temperature and some defects appeared when the temperature was too high.In addition,to further improve the film quality,an effective post-treatment approach was proposed and the experimental results showed that the microstructure of the Zn(O,S)thin film was improved by an ammonia etching process followed by an annealing process.For com-parison purposes,both Zn(O,S)-based and CdS-based devices were fabricated and characterized.The device with a Zn(O,S)-CIGS solar cell after post-treatment showed near conversion efficiency comparable to that of the device with the CdS-CIGS cell.

关键词： Zn(O,S) cadmium-free buffer layer chemical bath deposition reaction time deposition temperature post-treatment thin-film solar cell

MIL-53-based homochiral metal-organic framework as a stationary phase for open-tubular capillary electrochromatography

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Journal of Pharmaceutical Analysis 2022年第3期12卷 509-516页

作者： Xiaodong sun Bing Niu qi Zhang qin Chen School of Medicine Shanghai UniversityShanghai200444China School of Life Sciences Shanghai UniversityShanghai200444China School of Pharmacy Jiangsu UniversityZhenjiangJiangsu212013China

Homochiral metal-organic frameworks(MOFs)have attracted considerable attention in many fields of research,such as chiral catalysis and chiral chromatography.However,only few homochiral MOFs can be effectively used in capillary electrochromatography(CEC)and their performances are far from adequate.In this study,we successfully synthesized achiral nanocrystalline MIL-53.A facile post-synthetic modification strategy was then implemented to functionalize the product,yielding a homochiral MOF:L-His-NH-MIL-53.This MOF was then employed as a chiral coating in open-tubular CEC mode(OT-CEC),and,as such,it exhibited high enantioselectivities for several racemic drugs.The homochiral MOF and the fabricated capillary coating were systematically characterized using transmission electron microscopy,scanning electron microscopy(with energy-dispersive X-ray spectrometry),Fourier-transform infrared spectroscopy,X-ray diffractometry,thermogravimetric analysis,circular dichroism spectroscopy,Brunauer-Emmett-Teller surface area measurements,and X-ray photoelectron spectroscopy.This study is expected to provide a new strategy for the design and establishment of MOF-based chiral OT-CEC systems.

关键词： Homochiral MOF L-His-NH-MIL-53 Chiral stationary phase Capillary electrochromatography Enantioseparation

Power Curve Modeling for Wind Turbine Using Hybrid-driven Outlier Detection Method

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现代电力系统与清洁能源学报(英文) 2023年第4期11卷 1115-1125页

作者： qi Yao Yang Hu Jizhen Liu Tianyang Zhao Xiao qi Shanxun sun Energy and Electricity Research Center Jinan UniversityZhuhaiChina School of Control and Computer Engineering North China Electric Power UniversityBeijingChina

Wind power curve modeling is essential in the analysis and control of wind turbines(WTs),and data preprocessing is a critical step in accurate curve modeling.As traditional methods do not sufficiently consider WT models,this paper proposes a new data cleaning method for wind power curve modeling.In this method,a model-data hybrid-driven(MDHD)outlier detection method is constructed,and an adaptive update rule for major parameters in the detection algorithm is designed based on the WT model.Simultaneously,because the MDHD outlier detection method considers multiple types of operating data of WTs,anomaly detection results require further analysis.Accordingly,an expert system is developed in which a knowledgebase and an inference engine are designed based on the coupling relationships of different operating data.Finally,abnormal data are eliminated and the power curve modeling is completed.The proposed and traditional methods are compared in numerical cases,and the superiority of the proposed method is demonstrated.

关键词： Wind turbine power curve modeling outlier detection data-driven expert system

A novel compilation method of comprehensive mission spectrum of aero-engine maneuvering load based on use-related mission segment

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Chinese Journal of Aeronautics 2023年第3期36卷 161-170页

作者： Xuming NIU qi LU Zhigang sun Yingdong SONG Jiangsu Province Key Laboratory of Aerospace Power System and College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Laboratory of Aero-Engine Thermal Environment and Structure Ministry of Industry and Information Technology College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China College of Energy and Power Engineering and State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Comprehensive Mission Spectrum(CMS)of an aero-engine can reflect the usage characteristics of the engine.It can provide load input for engine life prediction and accelerated mission test.In this paper,a novel compilation method of CMS of aero-engine maneuvering load based on mission segment is proposed.Firstly,the use-related Typical Mission Segment(TMS)of maneuvering load is divided and identified according to spectral characteristics.Secondly,the mathematical model of different kinds of TMS are established based on stochastic process theory.Finally,the CMS of maneuvering load is compiled based on TMS.The proposed method can accurately quantify the compilation of CMS.The compiled CMS shows good agreement with the original load spectrum.According to damage consistency inspection,the compiled CMS is consistent with the damage caused by the original load spectrum in terms of low cycle fatigue.

关键词： Aero-engine Comprehensive mission spectrum Maneuvering load Spectrum compilation Typical mission segment

Kinetic roles of vibrational excitation in RF plasma assisted methane pyrolysis

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Journal of Energy Chemistry 2019年第12期28卷 188-197页

作者： Jintao sun qi Chen School of Mechanical Electronic and Control Engineering Beijing Jiaotong University

A combined experimental and simulational work was carried out in this paper to investigate the kinetic effects of non-equilibrium excitation by direct electron impact on low temperature pyrolysis of CH4 in a RF dielectric barrier discharge.Special attention was placed on the vibrational chemistry of CH4 and some other important products including H2,C2H2,C2H4,C2H6 and C3H8 largely produced in CH4/He discharge under an intermediate reduced electric field ranging 51-80 Td.A detailed kinetic mechanism incorporating a set of electron impact reactions,electron-ion recombination reactions,negative ions attachment reactions,charge exchange reactions,reactions involving vibrationally excited molecules and the relaxation process of vibrationally excited species was assembled and experimentally validated.The modeling results showed a reasonable agreement with the experimentally measured results in terms of CH4 conversion and products production including C2 hydrocarbons and hydrogen.A linear increasing trend of methane conversion with increasing plasma power input was discovered,which suggested a strong dependence of molecular excitation on energy input.Both the CH4/He mole ratio and the reactor temperature play significant roles in CH4 conversion and major products production.The experimental results showed that the selectivity of value-added products C2H4 and H2 keeps essentially unchanged with increasing energy input,mostly because the contribution CH4 ionization and He excitation effectively compete with vibrational excitation and dissociation of CH4 molecule with the E/N value increasing.The calculated results showed that the typical relaxation time of vibrational states is comparable to the gas-kinetics time in a CH4/He discharge mixture,thus the vibrationally excited molecules can significantly accelerate chemical reactions through an effective decrease of activation energy.The path flux analysis revealed that the vibrationally excited molecules CH4(v)and H2(v)enhanced chain propagation reactions,such as CH4(v)+H→CH

关键词： Non-equilibrium plasma Methane pyrolysis Vibrational excitation Path flux analysis Sensitivity analysis

Speech Encryption with Fractional Watermark

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Computers, Materials & Continua 2022年第10期73卷 1817-1825页

作者： Yan sun Cun Zhu qi Cui Key Laboratory of Artificial Intelligence Application Technology State Ethnic Affairs Commission Qinghai Minzu UniversityXining810007QinghaiChina School of Computer of qinghai Normal University Xining810003QinghaiChina The Department of Electrical and Computer Engineering University of WindsorWindsorN9B 3P4Canada

Research on the feature of speech and image signals are carried out from two perspectives,the time domain and the frequency domain.The speech and image signals are a non-stationary signal,so FT is not used for the non-stationary characteristics of the signal.When short-term stable speech is obtained by windowing and framing the subsequent processing of the signal is completed by the Discrete Fourier Transform(DFT).The Fast Discrete Fourier Transform is a commonly used analysis method for speech and image signal processing in frequency domain.It has the problem of adjusting window size to a for desired resolution.But the Fractional Fourier Transform can have both time domain and frequency domain processing capabilities.This paper performs global processing speech encryption by combining speech with image of Fractional Fourier Transform.The speech signal is embedded watermark image that is processed by fractional transformation,and the embedded watermark has the effect of rotation and superposition,which improves the security of the speech.The paper results show that the proposed speech encryption method has a higher security level by Fractional Fourier Transform.The technology is easy to extend to practical applications.

关键词： Fractional Fourier Transform watermark speech signal processing image processing

LADA strategy for the synthesis of unnatural amino acids and direct modifications of peptides

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Science China Chemistry 2023年第6期66卷 1788-1794页

作者： Jun-Liang Zhou Yun-qi Liu Zhan-Kui sun Shanghai Frontiers Science Center for Drug Target Identification and Drug Delivery School of Pharmaceutical SciencesShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Pharm-X CenterSchool of Pharmaceutical SciencesShanghai Jiao Tong UniversityShanghai 200240China AI Pharma Center Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai 200240China Shanghai Artificial Intelligence Laboratory Shanghai 200232China

Unnatural amino acids(UAAs)are important building blocks in organic synthesis and drug discovery.They are also frequently integrated into peptides or proteins for biological studies.However,the direct and simplified synthesis of UAAs remains a great challenge.At the same time,vast known peptide modifications are based on carbon-heteroatom bonds.There are no general methods for peptide modifications via the construction of C–C bonds.To address this challenge,herein we propose the LADA strategy,which is composed of two steps:the selective labeling and activation of cysteine residues,the desulfurization to generate carbon-centered radical and the radical addition to alkenes to build C–C bond.This one-pot protocol has obvious advantages such as good functional group tolerance,biocompatible reaction conditions,and retained stereochemistry.This strategy was successfully utilized for the synthesis of unnatural amino acids and direct modifications of peptides.

关键词： unnatural amino acids peptide modifications desulfurization cysteine radical addition