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Dynamic Promotional Resource Allocation for Segment Specific and Spectrum Effect of Promotion for a Product Line Incorporating Repeat Purchase Behavior 被引量:1
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作者 Prakash Chandra Jha Prerna Manik Anshu Gupta 《American Journal of Operations Research》 2013年第3期350-362,共13页
Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant... Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant and lack substantial growth because the brands would have low visibility in the market. Moreover, today’s vast and assorted markets comprise of customers with different needs and varied behavior. So it is rarely possible for companies to satisfy all customers by treating them alike. Thus there arises a need to divide the market into segments having customers with similar traits/characteristics. After identifying appropriate market segments, firms can design differentiated promotional campaigns for each segment. At the same time there can be a mass market promotional campaign that reaches different segments with a fixed spectrum. Also since promotional effort resources are limited, one must use them judiciously. In this paper, we formulate mathematical programming problem under repeat purchase scenario, which optimally allocates mass promotional effort resources and differentiated promotional effort resources across the segments dynamically in order to maximize the overall sales obtained from multiple products of a product line under budgetary and minimum sales aspiration level constraint on each product under consideration in each segment. The planning horizon is divided into multi periods, the adoption pattern of each product in each segment is observed in every subinterval and accordingly promotional effort allocations are determined for the next period till we reach the end of planning period. The optimization model has been further extended to incorporate minimum aspiration level constraints on total sales for each product under consideration from all the segments taken together. The non linear programming problem so formulated is solved using differential evolution approach. A numerical example has been discussed to illustrate applicability of the model. 展开更多
关键词 MARKET Segmentation DIFFERENTIATED MARKET PROMOTION Mass MARKET PROMOTION spectrum effect Promotional Effort Allocation REPEAT Purchase Product Line Non Linear Programming Problem Differential Evolution
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Photoreceptive reaction spectrum effect and phototactic activity intensity of locusts’ visual display characteristics stimulated by spectral light 被引量:5
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作者 Qihang Liu Yueli Jiang +4 位作者 Jin Miao Zhongjun Gong Tong Li Yun Duan Yuqing Wu 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2021年第2期19-25,共7页
To reveal the nature of locusts’visual reaction when stimulated by light,and to clarify the regulation characteristics of locusts’phototactic visual physiology and obtain good spectral light features for locusts’ph... To reveal the nature of locusts’visual reaction when stimulated by light,and to clarify the regulation characteristics of locusts’phototactic visual physiology and obtain good spectral light features for locusts’phototactic action,this study investigated locusts’visual spectrum response by characterizing their photoreceptive reaction to LED light using an AvaSpec fiber-optic spectrometer system.Locusts’phototactic response to spectral light was compared using this system.The results showed that locusts’visual reaction characterization presents a photo-induced vision spectrum effect and that by offsetting the main wavelength of light and the spectral peak intensity,a time-varying bio-regulation effect emerges.In addition,locusts’visual regulation ability to UV light is higher than that to violet light,whereas their reaction intensity is lower than to violet light,and the visual bio-regulatory force of locusts’visual system absorbing orange light to react sensitively becomes gradually higher than when absorbing green light as time goes on.Moreover,corresponding to nominal illumination with the same radiant energy and a visual spectrum response stimulated by UV,violet,orange,and green light,it appears that the visual spectrum window is symmetrical around 382 nm,400 nm,602 nm,and 530 nm,respectively,with no significant difference between spectral amplitudes and having a time-varying incremental characteristic with amplitude peak width.This indicates that the stimulus intensity of UV,violet,orange,and green light exceeds locusts’visual tolerance,causing them to generate regulation inactivation as a visual physiological reaction,whereas the visual window response effect stimulated by UV light presents an illumination timeliness effect.Simultaneously,time-varying characteristics of locusts’bio-behavior intensity show that light intensity can make up for locusts’visual sensitivity differences at various spectral wavelengths.Presented with differential response time,photosensitive behavior intensity,and induction effect induced by orange light,time is superior for orange light,the stimulation effect caused by violet light is the strongest,and the phototactic synergy effect caused by UV light is the best. 展开更多
关键词 Locusta migratoria manilensis photoreceptive spectrum effect visual reaction intensity photosensitive activity effect spectral illumination
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Spectrum-effect relationship between HPLC fingerprints and bioactive components of Radix Hedysari on increasing the peak bone mass of rat 被引量:6
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作者 Xin-Yue Chen San-Hu Gou +2 位作者 Zhi-Qiang Shi Zhi-Yuan Xue Shi-Lan Feng 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第4期266-273,共8页
The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in c... The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in collaterals, which is consistent with the principle of treatment for osteoporosis. This study is designed to investigate the bioactive components on increasing peak bone mass (PBM) by exploring the spectrum-effect relationship between chromatography fingerprints and effect. Multiple indicators are selected to evaluate the pharmacological activity. In fingerprints, 21 common peaks are obtained, five of which are identified. Furthermore, gray relational analysis (GRA) is a quantitative method of gray system theory and is used to describe the correlation degree of common peaks and pharmacological activities with relational value. 21 components are then divided into three different regions, of which ononin and calycosin play an extremely significant role in increasing PBM. In addition, factor analysis and hierarchical cluster analysis (HCA) are used to screen the optimal producing area for Radix Hedysari. This provides a comprehensive and efficient method to improve the quality evaluation of Radix Hedysari, confirming the bioactive components for PBM-enhancement and further develop its medicinal value. 展开更多
关键词 Factor ANALYSIS GRAY RELATIONAL ANALYSIS Hierarchical cluster ANALYSIS PEAK BONE mass RADIX Hedysari spectrum-effect relationship
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Effects of Hydrogen-bonding Interaction and Polarity on Emission Spectrum of Naphthalene-Triethylamine in Mixed Solvent
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作者 Yoshimi Sueishi Shunzo Yamamoto 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第5期606-611,共6页
The effects of the protic and aprotic polar solvents on the emission spectrum of the naphthalene-triethyl-amine system in THF were studied under conditions of steady-state illumination. The fluorescence spectrum of th... The effects of the protic and aprotic polar solvents on the emission spectrum of the naphthalene-triethyl-amine system in THF were studied under conditions of steady-state illumination. The fluorescence spectrum of the naphthalene-triethylamine system consists of two emission bands, the fluorescence band of naphthalene(band A, 329 nm) and the emission band of the exciplex(band B, 468 nm). The intensities of both the emission bands decrease with increasing the solvent polarity. The intensity of band B also decreases due to the hydrogen-bonding interaction between triethylamine and protic solvent, while that of band A increases. It is thus suggested that the quenching of naphthalene fluorescence by triethylamine in THF occurs through the charge transfer and electron transfer reactions. The spectral changes upon the increase of solvent polarity can be explained by the dependences of the equilibrium constant between exciplex and ion-pair and the rate constant for the electron transfer reaction from triethylamine to the excited naphthalene on the relative permittivity of solvent. It is shown that the formation of intermolecular hydrogen-bonding between triethylamine and protic solvent suppresses the quenching reaction by the decrease in free amine. Acetonitrile has only a polar effect and trichloroacetic acid only a hydrogen-bonding(or protonation) effect, while alcohols have both the effects. The effects of alcohols could be separated into the effects of solvent polarity and intermolecular hydrogen-bonding interaction quantitatively. 展开更多
关键词 Naphthalene-triethylamine Fluorescence spectrum Solvent effect Solvent polarity Hydrogen-bonding interaction.
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三七及其炮制品HPLC指纹图谱与体外抗氧化活性的谱效关系研究
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作者 唐林 鹿爱娟 +4 位作者 胡超 李海英 高元航 李昊 杨磊 《天然产物研究与开发》 北大核心 2026年第1期1-12,共12页
分析不同炮制三七的HPLC指纹图谱与体外抗氧化活性差异,并进行谱效关系研究。采用HPLC法建立36批次不同炮制三七(三七、蒸三七、油炸三七)的指纹图谱并对主要特征峰进行HPLC-Q-TOF-MS分析,结合主成分分析(principal component analysis,... 分析不同炮制三七的HPLC指纹图谱与体外抗氧化活性差异,并进行谱效关系研究。采用HPLC法建立36批次不同炮制三七(三七、蒸三七、油炸三七)的指纹图谱并对主要特征峰进行HPLC-Q-TOF-MS分析,结合主成分分析(principal component analysis,PCA)、层次聚类分析(hierarchical clustering analysis,HCA)、偏最小二乘回归分析(partial least squares regression,PLSR)对其进行质量评价并筛选差异标志物;通过DPPH自由基清除能力、FRAP总抗氧化能力和ABTS自由基清除能力测定评价其抗氧化活性;运用PLSR和皮尔逊(Pearson)分析三七及其炮制品化学成分与抗氧化活性的谱效关系。36批次不同炮制三七HPLC指纹图谱共37个特征峰,其中对33个特征峰进行了指认。PCA、HCA、PLSR将三七及其炮制品分为3类,并筛选出13个差异标志物。三七炮制后抗氧化活性显著增强,且抗氧化活性油炸三七>蒸三七>三七。6个特征性成分与三七抗氧化活性关联较大,包括麦芽三糖、人参皂苷Rh_(4)、人参皂苷F_(2)、人参皂苷Rg_(2)、人参皂苷Rk_(1)、人参皂苷Rg_(5)。本研究建立了基于化学成分和抗氧化活性的不同炮制三七质量评价模式,为阐明三七及其炮制品抗氧化活性成分及质量控制提供参考。 展开更多
关键词 三七 炮制 抗氧化 谱效关系 指纹图谱
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基于谱效-毒关系探讨川楝子醋炙减毒增效物质基础
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作者 牛乐 张雨 +2 位作者 范蒙蒙 李红伟 李凯 《中华中医药学刊》 北大核心 2026年第1期72-76,I0008,共6页
目的基于谱效关系和谱毒关系探讨川楝子醋炙减毒增效机理,为其进一步开发利用提供参考。方法采用UPLC双波长测定法,建立川楝子生品及醋炙品指纹图谱,结合主成分分析和偏最小二乘法分析评价川楝子醋炙前后成分变化;以二甲苯致耳肿胀为炎... 目的基于谱效关系和谱毒关系探讨川楝子醋炙减毒增效机理,为其进一步开发利用提供参考。方法采用UPLC双波长测定法,建立川楝子生品及醋炙品指纹图谱,结合主成分分析和偏最小二乘法分析评价川楝子醋炙前后成分变化;以二甲苯致耳肿胀为炎症模型,以炎症抑制率为指标考察川楝子醋炙前后抗炎活性;以血清中总胆汁酸(TBA)、谷草转氨酶(AST)、谷丙转氨酶(ALT)、碱性磷酸酶(ALP)的含量为指标考察川楝子醋炙前后肝毒性作用;采用灰色关联度法考察分析川楝子醋炙前后指纹图谱与抗炎作用和肝毒性的相关性。结果指纹图谱研究显示,生品与醋炙品在210、254 nm波长下分别共匹配16个和13个共有峰;采用主成分分析可将生川楝子与醋川楝子明显区分,采用正交偏最小二乘-判别分析筛选出醋炙前后共13个差异性成分。谱效关系结果显示川楝素、阿魏酸、芦丁、异槲皮苷是抗炎作用关联度较大的化学成分,谱毒关系结果显示川楝素是与肝毒性关联度最大的化学成分。结论川楝子醋炙后可有效降低肝毒性,并增强抗炎活性,川楝子醋炙减毒增效与川楝素、阿魏酸、芦丁、异槲皮苷的成分变化有关,这为川楝子醋炙品的临床应用提供依据。 展开更多
关键词 川楝子 醋炙 指纹图谱 化学模式识别 谱效-毒关系 抗炎作用 肝毒性
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Spectrum Diagnosis for Fuchsia Plume of Hall Effect Thruster with Xenon as Propellant
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作者 于达仁 丁佳鹏 戴景民 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第6期685-689,共5页
The colour of the Hall effect thruster's plume is often light-green, and sometimes a fuchsia plume appears during experiments. Based on a spectrum and colour analysis, and a comparison with normal plumes, a conclusio... The colour of the Hall effect thruster's plume is often light-green, and sometimes a fuchsia plume appears during experiments. Based on a spectrum and colour analysis, and a comparison with normal plumes, a conclusion is made that the density of the Xe ions and the temperature of electrons are low when the plume appears fuchsia. In this condition, most of the components of the plume are Xe atoms, and the ionization rate of the propellant is low. 展开更多
关键词 HET (Hall effect thruster) light-green plume fuchsia plume spectrum diagilosis
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基于谱效关系的黄连不同方法提取物抑菌作用物质基础初步研究
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作者 倪晓霞 陈巧秀 +1 位作者 杨育儒 曹毅祥 《药学实践与服务》 2026年第2期80-84,共5页
目的 建立黄连提取物的高效液相色谱法(HPLC)指纹图谱及其体外抑制金黄色葡萄球菌作用的谱-效关系,为探索黄连抑菌作用的药效物质基础提供依据。方法 分别以60%乙醇、1%盐酸甲醇以及水为提取溶剂,采用超声、加热回流以及浸泡等提取方法... 目的 建立黄连提取物的高效液相色谱法(HPLC)指纹图谱及其体外抑制金黄色葡萄球菌作用的谱-效关系,为探索黄连抑菌作用的药效物质基础提供依据。方法 分别以60%乙醇、1%盐酸甲醇以及水为提取溶剂,采用超声、加热回流以及浸泡等提取方法制备9种黄连提取物;建立提取物HPLC指纹图谱;以金黄色葡萄球菌为对象,根据培养基微量稀释法,采用酶标仪测定吸光度,计算抑菌率;运用灰色关联分析法(GRA)对谱-效数据进行关联分析。结果 建立9种黄连提取物的HPLC指纹图谱,确定9个共有特征指纹峰,通过对照品对比指认其中5个峰;GRA分析显示:9个共有峰成分与抑菌作用的关联度均在0.559 1~0.803 3之间;其中3号峰、8号峰(盐酸巴马汀)、9号峰(盐酸小檗碱)为正相关,其中9号峰(盐酸小檗碱)的相关度最高,其关联度值为0.803 3。结论 通过对黄连提取物谱-效关系进行研究,以盐酸小檗碱为主的生物碱类物质可能是黄连抑制金黄色葡萄球菌的主要药效物质基础。 展开更多
关键词 黄连 谱-效关系研究 药效物质基础 抑菌作用 金黄色葡萄球菌
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基于谱效关系的黔产铁角蕨科药用植物Q-marker的研究
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作者 梁永江 胡惠淇 +2 位作者 杨再贵 左雅敏 伍庆 《贵州科学》 2026年第1期32-40,共9页
目的:研究黔产铁角蕨科药用植物的指纹图谱与其体外抗结肠炎作用的谱效关系。方法:建立铁角蕨挥发油指纹图谱、溃疡性结肠炎小鼠模型,考察药材抗炎活性;以灰色关联度和偏最小二乘法结合分析药材共有峰与其抗炎的谱效关系。结果:10批铁... 目的:研究黔产铁角蕨科药用植物的指纹图谱与其体外抗结肠炎作用的谱效关系。方法:建立铁角蕨挥发油指纹图谱、溃疡性结肠炎小鼠模型,考察药材抗炎活性;以灰色关联度和偏最小二乘法结合分析药材共有峰与其抗炎的谱效关系。结果:10批铁角蕨药材挥发油的指纹图谱共有峰25个,并指认出其中7个成分:芳樟醇(峰17)、叶绿醇(峰5)、β-紫罗兰酮(峰16)、樟脑(峰12)、壬醛(峰6)、棕榈酸(峰18)及十五烷酸(峰13),指标成分总含量占药材生药量的59.01%~71.32%。与模型组比,给药组能改善小鼠便血症状和体质量(P<0.01),增加结肠长度(P<0.01),降低血清炎症因子(TNF-α、IL-6)含量及升高IL-10的含量。各共有峰峰面积与综合药效指标的GRA均大于0.5,PLSR表明峰1、20、11、24、17(芳樟醇)、6(壬醛)、15、13(十五烷酸)为黔产铁角蕨科植物抗炎活性特征成分。结论:研究表明,铁角蕨挥发油具备抗溃疡性结肠炎活性,且该活性是多种成分协同作用的结果,为铁角蕨Q-marker研究提供了参考。 展开更多
关键词 铁角蕨科药用植物 溃疡性结肠炎 谱-效模型 HS-SPME-GC Q-marker
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Conformations of Carnosine in Aqueous Solutions by All-Atom Molecular Dynamics Simulations and 2D-NOSEY Spectrum
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作者 张荣 王丹 吴文娟 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第1期67-72,I0004,共7页
All-atom molecular simulations and two-dimensional nuclear overhauser effect spectrum have been used to study the conformations of carnosine in aqueous solution. Intramolecular distances, root-mean-square deviation, r... All-atom molecular simulations and two-dimensional nuclear overhauser effect spectrum have been used to study the conformations of carnosine in aqueous solution. Intramolecular distances, root-mean-square deviation, radius of gyration, and solvent-accessible surface are used to characterize the properties of the carnosine. Carnosine can shift between extended and folded states, but exists mostly in extended state in water. Its preference for extension in pure water has been proven by the 2D nuclear magnetic resonance (NMR) experiment. The NMR experimental results are consistent with the molecular dynamics simulations. 展开更多
关键词 All-atom molecular simulation Carnosine aqueous solution Two-dimensionalnuclear overhauser effect spectrum
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基于谱-效关系的青刺尖抗氧化活性成分分析
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作者 桂鹏燕 杨秀霞 +1 位作者 杨兆祥 曲丽萍 《食品工业科技》 北大核心 2026年第4期348-359,共12页
为探究青刺尖(Prinsepia utilis Royle)主要抗氧化活性成分,阐明其药效物质基础,本研究以1,1-二苯基-2-三硝基苯肼自由基(1,1-diphenyl-2-picryl-hydrazyl radical,DPPH·)清除率为指标,采用高效液相色谱(high performance liquid c... 为探究青刺尖(Prinsepia utilis Royle)主要抗氧化活性成分,阐明其药效物质基础,本研究以1,1-二苯基-2-三硝基苯肼自由基(1,1-diphenyl-2-picryl-hydrazyl radical,DPPH·)清除率为指标,采用高效液相色谱(high performance liquid chromatography,HPLC)建立11批青刺尖提取物指纹图谱,并结合皮尔逊、斯皮尔曼和偏最小二乘回归分析探讨了指纹图谱共有峰与抗氧化作用间的谱-效关系,筛选出对抗氧化活性贡献较大的组分进行质谱定性和高效液相色谱定量分析,进一步通过体外DPPH·、ABTS^(+)·、·OH清除能力和人皮肤成纤维细胞(human foreskin fibroblasts,HFF)抗衰活性检测,评价其抗氧化及抗衰活性。结果从11批青刺尖提取物指纹图谱中标定13个色谱峰,并识别出其中6个化学成分,其中芦丁、水仙苷、碟豆素、夏佛塔苷和香蒲新苷等化合物为青刺尖发挥抗氧化功效的潜在物质成分,定量分析结果表明各化学成分的含量存在一定差异,碟豆素含量最高(738.123μg/mL),其次是芦丁(538.612μg/mL)、水仙苷(385.881μg/mL)和香蒲新苷(337.168μg/mL),且各单体化合物均表现出较好的自由基清除活性和良好的抗衰效果,其中芦丁和水仙苷能有效清除DPPH·、ABTS^(+)·及·OH,其中芦丁对DPPH·和ABTS^(+)·的清除率分别为92.84%和92.44%,对·OH清除作用的IC_(50)值为0.45 mg/mL;水仙苷对DPPH·和ABTS^(+)·的清除率为37.71%和82.01%,·OH清除作用的IC_(50)值为1.01 mg/mL。夏佛塔苷、香蒲新苷(P<0.01)及芦丁(P<0.05)可显著抑制SA-β-gal活性,降低衰老相关β-半乳糖苷酶阳性细胞比例,显示出良好的抗衰效果;细胞氧化应激模型中,香蒲新苷、蝶豆素、水仙苷及夏佛塔苷、芦丁能显著下调MMP-1、MMP-3和MMP-9的表达(P<0.001),促进皮肤胶原蛋白合成并抑制其降解,具有潜在的抗衰老能力。综上表明青刺尖的抗氧化功效可能是由夏佛塔苷、香蒲新苷、芦丁、水仙苷及碟豆素等多种化学成分共同作用产生的结果。 展开更多
关键词 青刺尖 抗氧化 谱-效关系 Pearson 相关性 偏最小二乘回归
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基于网络药理学和HPLC谱效关系的黄连改善2型糖尿病潜在质量标志物研究
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作者 万萧 保瑞 +2 位作者 毛海龙 王泽峰 闫鸿丽 《分析测试学报》 北大核心 2026年第2期390-397,共8页
该文系统开展了黄连改善2型糖尿病的潜在质量标志物筛选研究。通过整合网络药理学与高效液相色谱(HPLC)指纹图谱谱效关系分析方法,首先构建了“成分-靶点-疾病”网络,筛选出黄连碱、药根碱等6种核心活性成分,并建立10批次药材的HPLC指... 该文系统开展了黄连改善2型糖尿病的潜在质量标志物筛选研究。通过整合网络药理学与高效液相色谱(HPLC)指纹图谱谱效关系分析方法,首先构建了“成分-靶点-疾病”网络,筛选出黄连碱、药根碱等6种核心活性成分,并建立10批次药材的HPLC指纹图谱。结合α-葡萄糖苷酶抑制活性与抗氧化实验,采用灰色关联度及二元回归分析发现,小檗碱、黄柏酮、表小檗碱和黄连碱4种成分与降糖活性呈显著正相关。主成分分析及聚类分析显示不同批次药材存在明显的质量差异。该研究建立了“活性导向”的质量评价模式,突破传统“成分导向”的局限,明确了黄连治疗2型糖尿病的4种核心质量标志物。研究结果为黄连药材标准化生产、质量控制及临床精准用药提供了科学依据,对推动中药现代化和循证医学发展具有重要意义。 展开更多
关键词 黄连 2型糖尿病 网络药理学 指纹图谱 谱效关系 质量标志物
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基于谱效关系分析牡丹皮炭止血活性成分
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作者 梁清光 林希光 孟江 《中国实验方剂学杂志》 北大核心 2026年第4期183-190,共8页
目的:基于牡丹皮炭指纹图谱与止血药效之间的谱效关系,寻找牡丹皮炭的主要止血活性成分,为明确牡丹皮炭止血活性成分提供依据。方法:采用超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(UPLC-Q-Orbitrap MS/MS)建立16批牡丹皮炭水提... 目的:基于牡丹皮炭指纹图谱与止血药效之间的谱效关系,寻找牡丹皮炭的主要止血活性成分,为明确牡丹皮炭止血活性成分提供依据。方法:采用超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(UPLC-Q-Orbitrap MS/MS)建立16批牡丹皮炭水提液的指纹图谱,确定共有峰。采用半自动凝血分析仪测定16批样品的体外凝血活性指标活化部分凝血活酶时间(APTT)。综合运用灰色关联度分析(GRA)、Pearson相关性分析及偏最小二乘回归分析(PLSR)筛选潜在的止血活性成分。对筛选出的活性成分,进一步通过体外凝血三项实验检测APTT、凝血酶原时间(PT)、凝血酶时间(TT),斑马鱼脑出血模型评价止血率及实时荧光定量聚合酶链式反应(Real-time PCR)检测凝血因子Ⅹ(FⅩ)mRNA表达水平,进行多维度药效验证。结果:成功建立了牡丹皮炭水提液的UPLC指纹图谱,标定12个共有峰,并通过UPLC-Q-Orbitrap MS/MS鉴定出其中9个化学成分。经GRA、Pearson相关性分析和PLSR筛选出5-羟甲基糠醛(5-HMF)、没食子酸、1-O-没食子酰葡萄糖和对羟基苯甲酸为牡丹皮炭的关键止血活性成分。体外凝血三项实验证实,该4种活性成分均能明显缩短APTT和PT(P<0.05,P<0.01)。斑马鱼脑出血模型进一步验证了其体内止血效果,各活性成分均能降低脑出血面积(P<0.05,P<0.01),5-HMF、没食子酸、1-O-没食子酰葡萄糖和对羟基苯甲酸止血率分别为31.20%、68.85%、45.45%和45.60%,且止血效果总体呈现浓度依赖性。Real-time PCR测表明,活性成分均可上调FⅩmRNA的表达水平(P<0.05,P<0.01),协同促进止血。结论:该研究通过整合谱效关系分析与多维度药效验证,从牡丹皮炭中筛选出4个止血活性成分,为阐明牡丹皮炭止血活物质基础提供科学依据。 展开更多
关键词 牡丹皮 炭药 谱效关系 止血活性成分 超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(UPLC-QOrbitrap MS/MS)
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谱效关系在中药药效物质基础研究中的应用
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作者 沈细文 乌日拉嘎 杨立国 《中国民族民间医药》 2026年第3期75-80,共6页
中药指纹图谱可在整体上控制中药质量,近年来已成为一种被国内外广泛认可的质量控制方法。然而,指纹图谱中所体现的化学成分与药效相关程度尚不明确。谱效关系通过研究指纹图谱中化学成分与药效作用的相关性,可初步揭示中药药效物质基... 中药指纹图谱可在整体上控制中药质量,近年来已成为一种被国内外广泛认可的质量控制方法。然而,指纹图谱中所体现的化学成分与药效相关程度尚不明确。谱效关系通过研究指纹图谱中化学成分与药效作用的相关性,可初步揭示中药药效物质基础。文章对谱效关系在中药药效物质基础研究中的应用进行总结,以期为深入研究中药药效物质基础提供参考。 展开更多
关键词 谱效关系 指纹图谱 药效物质基础
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群智通信对抗环境下的认知干扰频谱资源决策方法
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作者 戴进 童晓兵 +5 位作者 冯智斌 徐逸凡 孙玉洁 贺兴 战志远 许江 《兵工学报》 北大核心 2026年第1期385-395,共11页
现代化战争中,群智通信对抗已成为认知电子战的重要发展趋势。现有认知干扰手段主要聚焦于单目标对抗场景,随着敌方目标设备抗干扰能力的提升和规模的扩大,难以达到理想的干扰效果。然而多干扰机在协同过程中内部关系耦合复杂且往往存... 现代化战争中,群智通信对抗已成为认知电子战的重要发展趋势。现有认知干扰手段主要聚焦于单目标对抗场景,随着敌方目标设备抗干扰能力的提升和规模的扩大,难以达到理想的干扰效果。然而多干扰机在协同过程中内部关系耦合复杂且往往存在决策冲突,导致干扰频谱资源浪费、协作效率低下,无法满足干扰的时效性需求。针对此问题,提出群智通信对抗环境下的认知干扰频谱资源博弈决策架构及方法,在博弈论和机器学习理论方法的指导下,围绕协同干扰博弈决策模型与效果评估机理、面向瞬时均衡收益的干扰高效决策压制以及面向长期累积收益的干扰稳健决策占优等多个方面,对关键技术展开论述,通过构建“内部协同、外部对抗”博弈模型与间接效果评估机制,缓解反馈缺失问题,并结合合作式多智能体学习提升联合决策能力。新方法在压制能力、协同效率和策略稳定性上均优于现有方法。 展开更多
关键词 通信干扰 认知干扰 干扰效果评估 频谱决策 博弈学习
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Decoupling of temporal/spatial broadening effects in Doppler wind LiDAR by 2D spectral analysis 被引量:1
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作者 刘珍 张云鹏 +3 位作者 竹孝鹏 刘继桥 毕德仓 陈卫标 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期447-452,共6页
Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and freque... Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and frequency dimension to cope with the temporal wind shear and achieve the optimal accumulation time.A hardware-efficient algorithm combining the interpolation and cross-correlation is used to enhance the wind retrieval accuracy by reducing the frequency sampling interval and then reduce the spectral width calculation error.Moreover,the temporal broadening effect and spatial broadening effect are decoupled according to the strategy we developed. 展开更多
关键词 Doppler wind LiDAR spectral analysis hardware efficiency spectrum broadening effects
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Energy spectrum measurement and dose rate estimation of natural neutrons in Tibet region 被引量:1
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作者 吴建华 徐勇军 +1 位作者 刘森林 汪传高 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第6期25-28,共4页
In this work, natural neutron spectra at nine sites in Tibet region were measured using a multi-sphere neutron spectrometer. The altitude-dependence of the spectra total fluence rate and ambient dose equivalent rate w... In this work, natural neutron spectra at nine sites in Tibet region were measured using a multi-sphere neutron spectrometer. The altitude-dependence of the spectra total fluence rate and ambient dose equivalent rate were analyzed. From the normalized natural neutron spectra at different altitudes, the spectrum fractions for neutrons of greater than 0.1 MeV do not differ obviously, while those of the thermal neutrons differ greatly from each other. The total fluence rate, effective dose rate and the ambient dose equivalent rate varied with the altitude according to an exponential law. 展开更多
关键词 中子能谱测量 西藏地区 剂量率 剂量当量率 估算 天然 能量密度 高度变化
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Analysis of the Zeeman effect on Dαspectra on the EAST tokamak 被引量:1
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作者 高伟 黄娟 +8 位作者 吴承瑞 许棕 侯玉梅 金钊 陈颖杰 张鹏飞 张凌 吴振伟 EAST Team 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第4期276-282,共7页
Based on the passive spectroscopy,the D_α atomic emission spectra in the boundary region of the plasma have been measured by a high resolution optical spectroscopic multichannel analysis(OSMA) system in EAST tokama... Based on the passive spectroscopy,the D_α atomic emission spectra in the boundary region of the plasma have been measured by a high resolution optical spectroscopic multichannel analysis(OSMA) system in EAST tokamak.The Zeeman splitting of the D_α spectral lines has been observed.A fitting procedure by using a nonlinear least squares method was applied to fit and analyze all polarization π and ±σ components of the D_α atomic spectra to acquire the information of the local plasma.The spectral line shape was investigated according to emission spectra from different regions(e.g.,low-field side and high-field side) along the viewing chords.Each polarization component was fitted and classified into three energy categories(the cold,warm,and hot components) based on different atomic production processes,in consistent with the transition energy distribution by calculating the gradient of the D_α spectral profile.The emission position,magnetic field intensity,and flow velocity of a deuterium atom were also discussed in the context. 展开更多
关键词 Zeeman effect PLASMA spectrum DEUTERIUM
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Study on fluorescence properties of rare earth complexes influenced by steric effect 被引量:5
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作者 袁伟 崔玉民 +7 位作者 师瑞娟 陶栋梁 王永忠 张文保 陈继堂 孙林 刘少轩 徐怡庄 《Journal of Rare Earths》 SCIE EI CAS CSCD 2011年第11期1013-1017,共5页
The rare earth complexes Tb(o-BrBA)3,Tb(m-BrBA)3 and Tb(p-BrBA)3 were synthesized using o-,m-,p-bromo benzoic acids(2-bromo benzoic acid,3-bromo benzoic acid and 4-bromo benzoic acid) as ligand,respectively.Th... The rare earth complexes Tb(o-BrBA)3,Tb(m-BrBA)3 and Tb(p-BrBA)3 were synthesized using o-,m-,p-bromo benzoic acids(2-bromo benzoic acid,3-bromo benzoic acid and 4-bromo benzoic acid) as ligand,respectively.The UV spectra showed that the absorption ability of Tb(m-BrBA)3 was the strongest.However,the fluorescent intensity of Tb(o-BrBA)3 was the weakest.The effect of the molecular structure,the energy level of Tb3+ and energy transfer efficiency from ligands to Tb3+ were discussed to explain the experimental results.The results indicated that,due to the large atomic radius of bromine,the steric effect caused by the different substitution bromine on the benzene ring might strongly affect the bond length formed by the coordination atoms and Tb3+.The longer the bond length was,the lower the efficiency of energy transfer was,and the weaker the fluorescent intensity was. 展开更多
关键词 terbium complexes bromo benzoic acid steric effect fluorescent spectrum rare earths
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