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Systematic screening and structural characterization of dipeptides using offline 2D Lc-LTQ-Orbitrap MS:A case study of cordyceps sinensis

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Journal of Pharmaceutical Analysis 2022年第2期12卷 263-269页

作者： Xiaodie Li changliang Yao Yun Li zhengming qian c Wenlong Wei Jianqing Zhang Jiayuan Li Qirui Bi Wenjia Li Yajun cui De-an Guo Shanghai Research center for Modernization of Traditional chinese Medicine National Engineering Laboratory for Traditional Chinese Medicine Standardization TechnologyShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China Shanghai University of Traditional chinese Medicine Shanghai201203China Key Laboratory of State Administration of Traditional chinese Medicine Sunshine Lake Pharma Co.LtdDongguanGuangdong523850China

cordyceps sinensis(***)is a widely used and highly valuable traditional chinese *** dipeptides have been detected in ***,but current scientific knowledge of its chemical makeup remains *** this study,an improved approach that integrates offline two-dimensional liquid chromatography(2D Lc)separation,precursor ion list,library screening,and diagnostic ion filtering was established to systematically screen and characterize dipeptides in *** 2D Lc integrating hydrophilic interaction Lc and reverse phase separations was established to eliminate interference and identify the target dipeptides.A library containing the potential 400 dipeptides was created,and a precursor ion list with all theoretical precursor ions was adopted to trigger the MS/MS scan with high *** identify dipeptides,the type and connection sequence of amino acids were determined according to the product *** and Leu residues were differentiated for the first time according to the characteristic ion at m/z ***,170 dipeptides were identified or tentatively characterized from ***,and most are reported for the first time in this species *** addition,the identified dipeptides were also applied for discrimination among the three cordyceps species,and 11 markers were *** obtained results provide a deeper understanding of the chemical basis of ***.

关键词： Dipeptides cordyceps sinensis Two-dimensional liquid chromatography Identification Isoleucine

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Analysis of cordyceps by multi-column liquid chromatography

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Acta Pharmaceutica Sinica B 2017年第2期7卷 202-207页

作者： zhengming qian Shaoping Li Institute of chinese Medical Sciences University of MacaoMacaoChina Key Laboratory of State Administration of Traditional chinese Medicine Sunshine Lake Pharma Co.Ltd.Dongguan 523850China

cordyceps is a famous traditional chinese medicine (TcM) that has been used in china for hundreds of years. In the present study a multi-column liquid chromatography (Mc-Lc) system was developed for the qualitative analysis of macromolecules and micromolecules in cordyceps. The Mc-Lc system includes a size exclusion pre-column, a size exclusion column (SEc) and a reversed phase column (RP) which were controlled by column-switching valves. The sample was separated by the size exclusion pre-column into two fractions (macromolecules and micromolecules). These fractions were further separated on SEc and RP columns, respectively. A diode array detector (DAD) and a mass spectrometer (MS) were used to detect the components. This Mc-Lc method was utilized for analysis of cordyceps samples. Two macromolecular peaks and 15 micromolecular peaks were found in cordyceps, and 11 of the micromolecular peaks were identified as adenosine-5'-monophosphate (AMP), phenylalanine, uridine, hypoxanthine, inosine, guanine, guanosine, deoxyadenosine-5'-monophosphate (dAMP), adenosine, adenine and cordycepin (or its isomer). This method is useful for quality control of cordyceps. (c) 2017 chinese Pharmaceutical Association and Institute of Materia Medica, chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.

关键词： cordycepie Macromocules Micromolecules Multi-column Size exclusion column

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Development of a nomogram for overall survival in patients with esophageal carcinoma:A prospective cohort study in china

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 158-168页

作者： Shi-Shi Yu Xi Zheng Xiao-Sheng Li qian-Jie Xu Wei Zhang Zhong-Li Liao Hai-Ke Lei Department of Gastroenterology Chongqing University Cancer HospitalChongqing 400030China chongqing cancer Multi-omics Big Data Application Engineering Research center Chongqing University Cancer HospitalChongqing 400030China Department of Health Statistics School of Public HealthChongqing Medical UniversityChongqing 400016China

BAcKGROUND Esophageal carcinoma(Ec)presents a significant public health issue in china,with its prognosis impacted by myriad *** creation of a reliable prog-nostic model for the overall survival(OS)of Ec patients promises to greatly advance the customization of treatment *** To create a more systematic and practical model that incorporates clinically significant indicators to support decision-making in clinical *** This study utilized data from a prospective longitudinal cohort of 3127 Ec patients treated at chongqing University cancer Hospital between January 1,2018,and December 12,*** the least absolute shrinkage and selection operator regression alongside multivariate cox regression analyses helped pinpoint pertinent variables for constructing the *** efficacy was assessed by concordance index(c-index),area under the receiver operating characteristic curve(AUc),calibration curves,and decision curve analysis(DcA).RESULTS Nine variables were determined to be significant predictors of OS in Ec patients:Body mass index(BMI),Karnofsky performance status,TNM stage,surgery,radiotherapy,chemotherapy,immunotherapy,platelet-to-lymphocyte ratio,and albumin-to-globulin ratio(ALB/GLB).The model demonstrated a c-index of 0.715(95%cI:0.701-0.729)in the training cohort and 0.711(95%cI:0.689-0.732)in the validation *** the training cohort,AUcs for 1-year,3-year,and 5-year OS predictions were 0.773,0.787,and 0.750,respectively;in the validation cohort,they were 0.772,0.768,and 0.723,respectively,illustrating the model's *** curves and DcA verified the model's predictive accuracy and net *** A novel prognostic model for determining the OS of Ec patients was successfully developed and validated to help clinicians in devising individualized treatment schemes for Ec patients.

关键词： Esophageal carcinoma High-risk factors Prognosis Overall survival Prediction model

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银发经济中备老人群消费特征与发展趋势研究

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新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 48-58,F0002页

作者：彭希哲陈倩复旦大学老龄研究院上海200433

银发经济已成为我国未来经济持续增长的重要领域,发展银发经济需要从供给和需求两方面同时发力。银发经济有特定的年龄针对性,文本关注银发经济中未老阶段的备老经济。备老人群呈现身体健康状况良好、预期寿命持续延长,文化教育水平较... 详细信息

银发经济已成为我国未来经济持续增长的重要领域,发展银发经济需要从供给和需求两方面同时发力。银发经济有特定的年龄针对性,文本关注银发经济中未老阶段的备老经济。备老人群呈现身体健康状况良好、预期寿命持续延长,文化教育水平较高、消费观念开放包容,互联网普及程度较高、消费个性化、注重悦己等群体特征,具有较强的消费能力和消费意愿,备老人群的消费将为银发经济带来巨大的增量空间。深入理解并满足备老人群的消费需求,对推动供需在更高水平实现良性循环、促进银发经济高质量发展具有重要意义。

关键词：银发经济备老经济高质量发展良性循环消费特征

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石墨烯褶皱结构对双电层储能性能的理论研究

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原子与分子物理学报 2025年第6期42卷 89-100页

作者：张倩蒋更平武汉科技大学理学院应用物理系武汉430081

石墨烯因其出色的比表面积和单层结构而被广泛认为是一种理想的电极材料.然而,实验制备的石墨烯常因官能团、缺陷和位错的引入而出现褶皱和变形.针对这一问题,本文构建了一系列具有不同幅度褶皱(a=0~6.6?)的石墨烯片,并运用分子动力学... 详细信息

石墨烯因其出色的比表面积和单层结构而被广泛认为是一种理想的电极材料.然而,实验制备的石墨烯常因官能团、缺陷和位错的引入而出现褶皱和变形.针对这一问题,本文构建了一系列具有不同幅度褶皱(a=0~6.6?)的石墨烯片,并运用分子动力学模拟来研究这些褶皱石墨烯表面的双电层结构.本研究旨在探讨不同褶皱高度和充电状态下双电层的变化规律,及其与超级电容器储能性能之间的关系.研究发现,褶皱石墨烯模型内部的离子浓度随电压的增加呈现多峰层状分布,而表面离子浓度与施加的电压正相关.此外,石墨烯的褶皱结构能够减少离子和水对电极电压响应的敏感性.在不同电压条件下,褶皱型石墨烯结构的面积比电容(c_A)始终高于其平面对应区域,突出了其在提升双电层储能性能上的优势.本研究揭示了石墨烯褶皱结构在调节离子分布、降低电压敏感性,以及增强电化学储能性能方面的特有作用机制.

关键词：双电层石墨烯褶皱恒电势模拟方法

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Manufacturing cost constrained topology optimization for additive manufacturing

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Frontiers of Mechanical Engineering 2019年第2期14卷 213-221页

作者： Jikai LIU qian cHEN Xuan LIANG Albert c.TO Department of Mechanical Engineering and Materials Science University of PittsburghPittsburghPA 15261USA

This paper presents a manufacturing cost constrained topology optimization algorithm considering the laser powder bed additive manufacturing *** optimization for additive manufacturing was recently extensively studied,and many related topics have been ***,metal additive manufacturing is an expensive process,and the high manufacturing cost severely hinders the widespread use of this ***,the proposed algorithm in this research would provide an opportunity to balance the manufheturing cost while pursuing the superior structural perfonnance through topology ***,the additive manufacturing cost model for laser powder bed-bascd process is established in this paper and real data is collected to support this ***,this cost model is transformed into a level set function-based expression,which is integrated into the level set topology optimization problem as a ***,by properly developing the sensitivity result,the metallic additive manufocturing part can be optimized with strictly constrained manufacturing *** of the proposed algorithm is proved by numerical design examples.

关键词： topology optimization manufacturing cost additive manufacturing powder bed

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Smart super rice

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Science china(Life Sciences) 2017年第12期60卷 1460-1462页

作者： qian qian state key laboratory for rice biology china national rice research instituteHangzhou 310006China

To commemorate the 50th anniversary of the published paper“Male Sterility in Rice”written by Professor Longping Yuan in the journal chinese Science Bulletin,Professor Qifa Zhang published a topical collection Fifty Glorious Years of Hybrid Rice by soliciting contributions in 2016,which he provided to the editorial department of chinese Science Bulletin.

关键词： Smart super rice

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A Multiple Exponential Smoothing Scheme For Quality control

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数理统计与管理 1993年第6期 46-54页

作者： c D LAI,DONG qian WANG Department of Statistics Massey University Department of Statistics Massey University Palmerston North New Zealand Palmerston North New Zealand

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Positive-instantaneous frequency and approximation

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Frontiers of Mathematics in china 2022年第3期17卷 337-371页

作者： Tao qian Macao center for Mathematical Science Macao University of Science and TechnologyMacaoChina

Positive-instantaneous frequency representation for transient signals has always been a great concern due to its theoretical and practical importance,although the involved concept itself is *** desire and practice of uniqueness of such frequency representation(decomposition)raise the related topics in *** approximately the last two decades there has formulated a signal decomposition and reconstruction method rooted in harmonic and complex analysis giving rise to the desired signal *** method decomposes any signal into a few basic signals that possess positive instantaneous *** theory has profound relations to classical mathematics and can be generalized to signals defined in higher dimensional manifolds with vector and matrix values,and in particular,promotes kernel approximation for multi-variate *** article mainly serves as a *** also gives two important technical proofs of which one for a general convergence result(Theorem 3.4),and the other for necessity of multiple kernel(Lemma 3.7).Expositorily,for a given real-valued signal f one can associate it with a Hardy space function F whose real part coincides with *** function F has the form F=f+iHf,where H stands for the Hilbert transformation of the *** develop fast converging expansions of F in orthogonal terms of the form F=∑k=1^(∞)c_(k)B_(k),where B_(k)'s are also Hardy space functions but with the additional properties B_(k)(t)=ρ_(k)(t)e^(iθ_(k)(t)),ρk≥0,θ′_(k)(t)≥0,*** original real-valued function f is accordingly expanded f=∑k=1^(∞)ρ_(k)(t)cosθ_(k)(t)which,besides the properties ofρ_(k)andθ_(k)given above,also satisfies H(ρ_(k)cosθ_(k))(t)ρ_(k)(t)sinρ_(k)(t).Real-valued functions f(t)=ρ(t)cosθ(t)that satisfy the conditionρ≥0,θ′(t)≥0,H(ρcosθ)(t)=ρ(t)sinθ(t)are called *** f is a mono-component,then the phase derivativeθ′(t)is defined to be instantaneous frequency of *** above described positive-instantaneou

关键词： Möbius transform blaschke product mono-component hilbert transform hardy space inner and outer functions adaptive fourier decomposition rational orthogonal system nevanlinna factorization beurling-lax theorem reproducing kernel hilbert space several complex variables clifford alge-bra pre-orthogonal AFD

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Representing conics by low degree rational DP curves

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Journal of Zhejiang University-Science c(computers and Electronics) 2010年第4期11卷 278-289页

作者： qian-qian HU Guo-jin WANG Department of Mathematics Zhejiang University Hangzhou 310027 China college of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 China

A DP curve is a new kind of parametric curve defined by Delgado and Pena （2003）; Jt has very good properties when used in both geometry and algebra, i.e., it is shape preserving and has a linear time complexity for evaluation. It overcomes the disadvantage of some generalized Ball curves that are fast for evaluation but cannot preserve shape, and the disadvantage of the B6zier curve that is shape preserving but slow for evaluation. It also has potential applications in computer-aided design and manufacturing （cAD/cAM） systems. As conic section is often used in shape design, this paper deduces the necessary and suffi- cient conditions for rational cubic or quartic DP representation of conics to expand the application area of DP curves. The main idea is based on the transformation relationship between low degree DP basis and Bemstein basis, and the representation tbeory of conics in rational low degree B6zier form. The results can identify whether a rational low degree DP curve is a conic section and also express a given conic section in rational low degree DP form, i.e., give positions of the control points and values of the weights of rational cubic or quartic DP conics. Finally, several numerical examples are presented to validate the effectiveness of the method.

关键词： conic sections Bernstein basis DP basis Rational low degree Bezier curves Rational low degree DP curves

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