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Atomic Spacetime Model Based on Atomic AString Functions 被引量:1
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作者 Sergei Yurievich Eremenko 《Journal of Applied Mathematics and Physics》 2022年第9期2604-2631,共28页
A novel model of spacetime and fields atomization based on Atomic Series over finite Atomic AString Functions is offered. Formulated Atomization Theorems allow representing polynomials, analytic functions, and solutio... A novel model of spacetime and fields atomization based on Atomic Series over finite Atomic AString Functions is offered. Formulated Atomization Theorems allow representing polynomials, analytic functions, and solutions of field equations including General Relativity via superposition of solitonic atoms which can be associated with flexible spacetime quantum, metriants, or elementary distortions. Spacetime is conceptualized as a lattice of flexible Atomic Solitons adjusting locations to reproduce different metrics and other physical fields. It may offer the variants of unified field theory based on Atomic Solitons where, like in string theory, fields become interconnected having a common mathematical ancestor. 展开更多
关键词 SPACETIME QUANTUM Atomic Function astring SOLITON Metriant Unified Theory
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Effects of Carbon Dioxide on Astringency Removal in Mopanshi Persimmon
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作者 LENG Ping, LI Bao, ZHANG Wen and JIA Ke-gong (College of Agricultural and Biotechnology, China Agricultural University, Beijing 100094, P. R. China) 《Agricultural Sciences in China》 CAS CSCD 2003年第12期1382-1386,共5页
Fruits of persimmon (Diospyros kaki cv. Mopanshi) were used to investigate the effects of different concentrations of carbon dioxide (CO 2) gas on removing astringency after harvest. Treatment of 95% concentration of... Fruits of persimmon (Diospyros kaki cv. Mopanshi) were used to investigate the effects of different concentrations of carbon dioxide (CO 2) gas on removing astringency after harvest. Treatment of 95% concentration of CO 2 gas gave the best results; fruits turned non-astringent after 20 h, and kept the fruit firm for 7 d at room temperature. Fruits, treated with 85 and 90% concentration of CO 2 gas, turned non-astringent after 2428 h, and the firmness-keeping stage was 56 d at room temperature. While the CO 2 gas was at 80, 70 and 60%, the de-astringency period was 48, 72 and 96 h, and the corresponding firmness-keeping stage was 3, 2 and 1 d, respectively. Fruits, treated with 50% concentration of CO 2 gas, remained astringent. 展开更多
关键词 PERSIMMON Carbon dioxide astringency removal Firmness-keeping
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Therapy of Suppressing Yang and Astringing Yin for the Treatment of Cancer-Related Insomnia 被引量:1
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作者 Ranpei Zhu Xu Sun Yuling Zheng 《Chinese Medicine and Natural Products》 2022年第1期11-18,共8页
The pathogenesis of can cer-related in som nia(CRI)mainly in eludes,first,the flow of cancerous toxin leading to the disorder of visceral qi;second,cancer-related radiotherapy and chemotherapy belonging to"exogen... The pathogenesis of can cer-related in som nia(CRI)mainly in eludes,first,the flow of cancerous toxin leading to the disorder of visceral qi;second,cancer-related radiotherapy and chemotherapy belonging to"exogenous pathogenic factors"to a certain extent,which can further aggravate visceral disorders.The therapeutic principle of Chinese medicine is to tranquilize the mind on the basis of regulating viscera,suppressing yang,and astringing yin.On this theoretical basis,Professor Zheng Yuling created a representative prescription of Zhenjing Anshen Granules(镇静安神颗粒)which can achieve the co-regulation of the heart,liver,and kidney,tranquilizing the mind and nourishing the blood.Clinically,the selection of prescriptions and medicines needs to be considered due to factors such as different treatment stages and differ-ences in patients'constitutions. 展开更多
关键词 cancer related insomnia(CRI) suppressing yang and astringing yin Zhenjing Anshen Granules syndrome differentiation and treatment Yuling Zheng
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Molecular mechanisms of bitterness and astringency in the oral cavity induced by soyasaponin
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作者 Lijie Zhu Yueying Pan +3 位作者 Yingyan Li Yingjie Zhou He Liu Xiuying Liu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3424-3433,共10页
The interaction mechanism between soyasaponin(Ssa)and bitter receptors/mucin,as well as the saliva interface behavior of Ssa,were investigated to explore the presentation mechanism of Ssa bitterness and astringency(BA... The interaction mechanism between soyasaponin(Ssa)and bitter receptors/mucin,as well as the saliva interface behavior of Ssa,were investigated to explore the presentation mechanism of Ssa bitterness and astringency(BA).Strong bitterness arising from high Ssa concentrations(0.5–1.5 mg/mL)had a masking effect on astringency.At Ssa concentrations of 1.0–1.5 mg/mL,Ssa micelles altered the structure of mucin,exposing its internal tryptophan to a more polar environment.At Ssa concentrations of 0.05–1.50 mg/mL,its reaction with mucin increased the aggregation of particles in artificial saliva,which reduced the frictional lubricating properties of oral saliva.Ssa-mucin interactions affected the salivary interfacial adsorption layer,and their complexes synergistically reduced the interfacial tension.Ssa monomers and soyasapogenols bind to bitter receptors/mucin via hydrogen bonding and hydrophobic interactions.Class A Ssa binds more strongly than class B Ssa,and thus likely presents a higher BA.In conclusion,Ssa interacts with bitter receptors/mucin causing conformational changes and aggregation of salivary mucin,resulting in diminished frictional lubricating properties of oral saliva.This,in turn,affects taste perception and gustatory transmission. 展开更多
关键词 SOYASAPONIN Bitterness and astringency Bitter taste receptor MUCIN
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Screening Germplasm Resources of Tea Plant with Less Bitterness and Astringency Index
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作者 L. Y. Wu J. K. Lin 《Journal of Agricultural Science and Technology(B)》 2011年第6期874-880,共7页
The aim of this study was to identify tea varieties with less bitterness and astringency index that could be used as important sources for breeding and in the production of high quality tea. We studied 36 cultivars or... The aim of this study was to identify tea varieties with less bitterness and astringency index that could be used as important sources for breeding and in the production of high quality tea. We studied 36 cultivars or lines which had been preserved in Tea Germplasm Garden of Fujian. The contents of catechins in spring tea shoots, summer tea shoots and autumn tea shoots in 36 varieties and lines were analyzed by HPLC. Analysis of these tea varieties and lines revealed that the catechins contained in the tea shoots in different seasons are highly variable. The content of ester-catechins in spring and summer tea shoots was higher than that of autumn, while non-ester-catechins did not showed the same characteristic. The content of EGCG showed an extremely significant positive correlation with T1 (T1 = EGC + EGCG + GCG + EGC), an extremely significant negative correlation with DL-C, the content of EGC showed the same characteristic. Among them, 10 cultivars with less bitterness and astringency index (the annual average bitterness and astringency index 〈 8.0) were considered good candidates as important breeding materials tbr tea infusion quality improvement. 展开更多
关键词 Camellia sinensis ester-catechins BITTERNESS astringENCY germplasm resources screening.
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尤昭玲运用固涩药治疗女性生殖系统疾病经验介绍
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作者 庞卓超 尤昭玲 +2 位作者 张海童 杨雨晨 唐诗 《新中医》 2026年第2期129-135,共7页
尤昭玲教授临证时精准辨证施治,灵活运用莲类药、炭类药以及有固肾涩精、收敛固涩、重镇收敛等功效的固涩药治疗多囊卵巢综合征、子宫肌瘤、子宫假腔等多种女性生殖系统疾病,既能收敛病灶、止血,又可起到协助消积除癥的作用,在长期临床... 尤昭玲教授临证时精准辨证施治,灵活运用莲类药、炭类药以及有固肾涩精、收敛固涩、重镇收敛等功效的固涩药治疗多囊卵巢综合征、子宫肌瘤、子宫假腔等多种女性生殖系统疾病,既能收敛病灶、止血,又可起到协助消积除癥的作用,在长期临床实践中已取得良好疗效。 展开更多
关键词 女性生殖系统疾病 莲类药 炭类药 固涩药 尤昭玲
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南昆山毛叶茶关键呈涩多酚的鉴定及呈涩效应分析
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作者 严毅鹏 李斌 +4 位作者 龚兴鑫 陈渝 陈忠正 张媛媛 林晓蓉 《食品科学》 北大核心 2026年第2期152-161,共10页
本研究以南昆山毛叶茶(Camellia ptilophylla)绿茶为主要研究材料,以云南大叶种绿茶为传统茶树对照,采用感官审评结合基于人工唾液的浊度法、荧光猝灭法比较其呈涩强度,利用高效液相色谱分析经人工唾液处理后主要多酚的浓度变化,筛选主... 本研究以南昆山毛叶茶(Camellia ptilophylla)绿茶为主要研究材料,以云南大叶种绿茶为传统茶树对照,采用感官审评结合基于人工唾液的浊度法、荧光猝灭法比较其呈涩强度,利用高效液相色谱分析经人工唾液处理后主要多酚的浓度变化,筛选主要呈涩多酚单体,进而利用荧光光谱和分子对接技术探究呈涩多酚与唾液蛋白模型的相互作用,并结合基于高分辨质谱的非靶向代谢组学进一步挖掘其他呈涩多酚。结果表明,南昆山毛叶绿茶涩感比云南大叶种绿茶更强,以没食子儿茶素没食子酸酯、1,2,4,6-四没食子酰葡萄糖、没食子儿茶素-3,5-双没食子酸酯为主要呈涩多酚,通过以疏水相互作用为主、氢键结合为辅的方式与唾液蛋白模型结合,南昆山毛叶绿茶中的杨梅素、大黄素、花旗松素同样与唾液蛋白模型具有高结合率。本研究揭示了南昆山毛叶绿茶呈涩的化学基础,可为进一步阐释其呈涩机理、探索涩感改善方法奠定前期研究基础。 展开更多
关键词 南昆山毛叶茶 涩感 呈涩多酚 人工唾液 相互作用
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不同黄瓜品种涩味性状差异分析
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作者 许心田 任思铃 +1 位作者 朱雪云 孔维良 《中国瓜菜》 北大核心 2026年第1期94-101,共8页
涩味是影响黄瓜口感品质的重要性状。为了在黄瓜涩味品质研究与育种中筛选出理想的研究材料,采用口感评价的方法,系统分析比较了6个黄瓜品种商品瓜的涩味强度、稳定性及果实不同部位涩味强度分布等。结果表明,不同品种涩味强度存在差异,... 涩味是影响黄瓜口感品质的重要性状。为了在黄瓜涩味品质研究与育种中筛选出理想的研究材料,采用口感评价的方法,系统分析比较了6个黄瓜品种商品瓜的涩味强度、稳定性及果实不同部位涩味强度分布等。结果表明,不同品种涩味强度存在差异,H-1和H-4涩味强度较高,O-1涩味强度相对较低。此外,春茬栽培的黄瓜涩味指数(表示黄瓜涩味强度)普遍高于秋茬。对涩味指数极差、标准差和变异系数的分析显示,6个品种涩味极差最低为37.5(春茬)和47.5(秋茬),标准差最低为11.49(春茬)和11.46(秋茬),绝大多数品种的变异系数大于20%。其中H-3的3个变异指标总体表现较高,说明其涩味性状稳定性较低。春茬除O-1和N-1外,5月的平均涩味指数与6月没有显著差异,秋茬各品种10月和11月的平均涩味指数均无显著差异,但是每间隔3~5 d采收的单瓜间涩味指数存在不同程度的波动,尤以H-3波动更为剧烈。除H-4外,黄瓜花冠段涩味指数显著低于果梗段,且两段涩味指数呈显著正相关。综上,不同黄瓜品种的涩味强度、稳定性及变异程度存在显著差异,在本试验条件下,O-1与N-1表现为较稳定的低涩味特性,H-1与H-4具有较稳定的高涩味强度,而H-3的变异性最为突出。本研究结果为黄瓜涩味品质评价及育种中涩味材料的选择奠定了基础。 展开更多
关键词 黄瓜 涩味 口感评价 变异系数
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非单宁酚与缩合单宁的相互作用及其对葡萄酒涩感的影响
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作者 谢樱萍 潘秋红 《中外葡萄与葡萄酒》 北大核心 2026年第1期110-120,共11页
葡萄酒涩感是决定消费者接受度与风格定位的核心感官属性之一,传统上归因于缩合单宁与口腔唾液蛋白的特异性结合。近年研究表明,非单宁酚(酚酸、黄酮、花色苷、香豆素及木质素等)作为另一类关键酚类群体,对涩感表达具有显著调节作用。... 葡萄酒涩感是决定消费者接受度与风格定位的核心感官属性之一,传统上归因于缩合单宁与口腔唾液蛋白的特异性结合。近年研究表明,非单宁酚(酚酸、黄酮、花色苷、香豆素及木质素等)作为另一类关键酚类群体,对涩感表达具有显著调节作用。本文梳理了葡萄酒非单宁酚的种类,评述其检测技术的进展,重点阐述了非单宁酚与缩合单宁在分子水平的相互作用机制及其对涩感动态特征的调控效应。最后,归纳了当前葡萄酒涩感研究的瓶颈,并展望了未来该领域的研究方向,以期为葡萄酒风味的精准设计提供理论依据和技术支撑。 展开更多
关键词 葡萄酒 非单宁酚 缩合单宁 涩感 相互作用
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A novel technology to reduce astringency of tea polyphenols extract and its mechanism 被引量:4
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作者 Jin-yan Wan Yu Long +4 位作者 Yu-lu Zhang Yan Xiang Song-yu Liu Nan Li Ding-kun Zhang 《Chinese Herbal Medicines》 CAS 2021年第3期421-429,共9页
Objective:Tea polyphenols are natural extracts used widely throughout the world.However,the severe astringency of tea polyphenols has reduced patient compliance.Based on the analysis of the formation mechanism of astr... Objective:Tea polyphenols are natural extracts used widely throughout the world.However,the severe astringency of tea polyphenols has reduced patient compliance.Based on the analysis of the formation mechanism of astringency,this paper hopes to propose a new method to control the astringency of tea polyphenols and improve patient compliance without changing its effect.Methods:Artificial saliva was used to prepare the tea polyphenols solution with different p H,using bcasein to imitate salivary protein,and preparing 1.2 mg/m L b-casein solution.A fluorescence quenching test was used to study the interaction between tea polyphenols and b-casein,combined with the stability test results of the compound,we can choose the p H with weak binding but good stability as the best p H for masking astringency.The taste-masking tablets were prepared under the best p H conditions,and the Xinnaojian Original Tablets were prepared according to the conventional preparation method.The disintegration time limit and solubility were tested respectively.The astringency of Xinnaojian original tablets and taste-masking tablets was evaluated by visual analogue scale(VAS).Results:The result of the fluorescence quenching test prompted that the combination force was the weakest when the p H was 4.9.Further synchronous fluorescence analysis showed that an increase in p H resulted in a decrease of the binding sites between tea polyphenols and b-casein,and this decrease was closely related to changes in tryptophan residues in b-casein.Both original and taste-masking Xinnaojian Tablets were prepared.Volunteers’VAS scores illustrated that the astringency improved significantly with the masking tablets(P<0.05).Conclusion:This p H-adjusting masking treatment had little effect on the recovery of polyphenols from the tablets or the dissolution of the tablets.This study provides a novel and feasible astringency masking technology for tea polyphenols and its preparation. 展开更多
关键词 astringENCY b-casein fluorescence quenching tea polyphenols
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A tribo-chemical view on astringency of plant-based food substances 被引量:2
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作者 Samuel S.GAMANIEL Paloma S.DUEÑAS ROBLES +3 位作者 Hans TROMP Els H.A.de HOOG Sissi de BEER Emile van der HEIDE 《Friction》 SCIE EI CAS CSCD 2024年第7期1392-1407,共16页
Consumption of plant-based food products having high composition of polyphenols leads to the sensation of astringency.For sliding oral surfaces,friction is an essential property during the oral perception of roughness... Consumption of plant-based food products having high composition of polyphenols leads to the sensation of astringency.For sliding oral surfaces,friction is an essential property during the oral perception of roughness and dryness which are attributes associated with astringency.Different factors including the chemical composition of interacting layers,structure and operation of interfaces have an effect on the astringency development process.The manner of interactions occurring at oral interfaces suggest there is a system dependence of astringency and highlights the importance of adopting a tribosystems approach.Available measurement techniques have shown an existing relationship between salivary protein-polyphenol interaction and an astringent mouthfeel.Nevertheless,the tribo-chemistry involved in this multifaceted sensation remains largely unexplored in a comprehensive manner.In this review the underlying tribo-chemical processes useful in understanding the mechanism of astringency are highlighted and discussed considering current techniques employed to investigate astringency perception.Loss of lubrication on oral surfaces owing to the tribo-chemical interactions involving saliva and astringent plant proteins requires subsequent deformations of oral tissues which are significant enough to induce strains at mechanoreceptor locations,leading to the sensation of astringency.It is proposed that micro-scale contact modelling on the interaction of food particles/aggregates,boundary layers and oral surfaces shows potential in addressing the knowledge gap between tribo-chemical measurement techniques and panel tests,making it possible to attain a predictor for astringency. 展开更多
关键词 oral lubrication astringENCY tribo-chemistry TRIBOLOGY
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植物蛋白处理对黑果腺肋花楸汁涩味及其品质的影响
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作者 古丽坚乃提·阿卜杜艾尼 刘婷婷 程志强 《食品研究与开发》 2026年第3期107-113,共7页
该研究考察植物蛋白(小麦水解蛋白、大豆分离蛋白、豌豆蛋白)减少黑果腺肋花楸汁总单宁从而降低涩味的能力,以及对果汁品质的影响,以确定替代明胶的植物蛋白。测定蛋白处理后的果汁总单宁、总缩合单宁去除率,总酚、总花青素保留率,透光... 该研究考察植物蛋白(小麦水解蛋白、大豆分离蛋白、豌豆蛋白)减少黑果腺肋花楸汁总单宁从而降低涩味的能力,以及对果汁品质的影响,以确定替代明胶的植物蛋白。测定蛋白处理后的果汁总单宁、总缩合单宁去除率,总酚、总花青素保留率,透光率和pH值,同时建立电子舌味觉检测结果的雷达图,并进行主成分分析。结果表明:小麦水解蛋白、大豆分离蛋白、豌豆蛋白、明胶均能降低总单宁;其中,小麦水解蛋白降低总单宁、总缩合单宁,保留总酚,提高果汁透光率的效果接近明胶的效果;豌豆蛋白和大豆分离蛋白降低总单宁效果相比于前两种稍差。电子舌结果显示,与明胶相比小麦水解蛋白可以更好地减少涩味和苦味,但小麦水解蛋白会影响果汁的总花青素保留率,这可能会影响果汁色泽,因此确定蛋白类型时需谨慎,基于需求选择使用。 展开更多
关键词 黑果腺肋花楸 单宁 植物蛋白 涩味 品质
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基于UPLC-Q-TOF非靶向代谢组学及分子对接技术的红葡萄酒酿造过程中单宁及涩感感知变化研究
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作者 石宝晖 宋琳娜 +4 位作者 孙晓涵 徐涛 魏子钰 郑浩博 马雯 《食品与发酵工业》 北大核心 2026年第5期363-372,共10页
为阐明红葡萄酒酿造过程中单宁结构演化对涩感感知的影响机制,该研究采用超高效液相色谱四极杆飞行时间质谱联用及感官定量描述分析法系统开展赤霞珠红葡萄酒酿造过程中12个关键时间点的单宁组分非靶向代谢组及涩感强度演变规律研究,并... 为阐明红葡萄酒酿造过程中单宁结构演化对涩感感知的影响机制,该研究采用超高效液相色谱四极杆飞行时间质谱联用及感官定量描述分析法系统开展赤霞珠红葡萄酒酿造过程中12个关键时间点的单宁组分非靶向代谢组及涩感强度演变规律研究,并运用分子对接技术解析单宁-唾液蛋白相互作用分子机制。研究结果显示:总酚含量与涩感强度均在发酵阶段显著升高,随后在陈酿阶段趋于稳定;单宁组分分析揭示了酿造过程中儿茶素类单宁占比呈下降趋势,棓儿茶素类和儿茶素没食子酸酯类单宁占比在发酵阶段先升高(峰值分别为19%和14%)后降低,陈酿阶段趋于稳定;单宁平均聚合度在酒精发酵期间从1.62大幅升高至2.38,在陈酿阶段保持稳定;非靶向代谢组学揭示了酿造过程中大部分儿茶素类单宁(DP1-1、DP2-1等)含量在发酵结束达峰值后陈酿阶段趋于稳定,大部分棓儿茶素类单宁(DP2+1P-2、DP3+1P-1等)含量在酿造过程中持续积累陈酿12个月时达到峰值,而大部分儿茶素没食子酸酯类单宁(DP1+1G-1、DP2+1G-1等)含量在发酵阶段达到峰值后陈酿阶段呈下降趋势;分子对接结果表明,单宁与胰腺α-淀粉酶间相互作用主要以氢键和疏水相互作用为主,儿茶素类单宁随聚合度增加结合强度逐渐增强,棓儿茶素类单宁随原花翠素比例增加结合强度略微降低,儿茶素没食子酸酯类单宁随酯化程度增加结合强度大幅增加,与涩感强度变化表现出高度一致性。该研究结果为红葡萄酒酿造过程中单宁复杂结构演变对涩感感知变化的影响提供了一定的理论基础。 展开更多
关键词 超高效液相色谱四极杆飞行时间质谱联用 分子对接 单宁 涩感 葡萄酒
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浓香型白酒基酒味觉特征与挥发性风味成分相关性研究
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作者 路瑞 王婷 +5 位作者 白玉 李永霞 郇丹 郭涛红 唐云 赵亚雄 《中国酿造》 北大核心 2026年第2期272-279,共8页
该研究以68个不同味觉特征(均衡、苦味、微涩、较涩、涩味)浓香型白酒基酒样品为研究对象,采用顶空固相微萃取-气相色谱-质谱联用技术(HS-SPME-GC-MS)结合多元统计分析方法,系统解析样品中挥发性风味成分的组成特征及其与味觉特征的相... 该研究以68个不同味觉特征(均衡、苦味、微涩、较涩、涩味)浓香型白酒基酒样品为研究对象,采用顶空固相微萃取-气相色谱-质谱联用技术(HS-SPME-GC-MS)结合多元统计分析方法,系统解析样品中挥发性风味成分的组成特征及其与味觉特征的相关性。结果表明,共鉴定出330种挥发性风味化合物,其中共有组分31种,特有组分25种,不同口感基酒的挥发性风味物质在种类和含量上均有明显差异。通过正交偏最小二乘法-判别分析(OPLS-DA)构建的模型可对不同味觉特征基酒进行区分,基于变量重要性投影(VIP)值≥1、P<0.05筛选出9-十六碳烯酸乙酯、十五酸乙酯等33种重要差异挥发性风味化合物,其分布模式与感官评价结果高度一致。层次聚类分析进一步揭示,苦味特征基酒中苯乙醛二乙缩醛、壬醛二乙缩醛等12种化合物呈现特异性富集,同时检测到28种主要涩味关联化合物,其种类及富集程度随涩味强度梯度变化呈现明显差异。 展开更多
关键词 浓香型白酒 基酒 味觉特征 苦涩味 挥发性风味物质 正交偏最小二乘-判别分析
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Preferential transport activity of Dk DTX5/MATE5 affects the formation of different astringency in persimmon
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作者 Ying Liu Xin Wu +6 位作者 Chenfeng Sun Wenxing Chen Meng Zhang Niannian Liu Qinglin Zhang Liqing Xu Zhengrong Luo 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2023年第10期2304-2319,共16页
Proanthocyanidins(PAs) are specialized metabolites that infuence persimmon fruit quality.Normal astringent(A)-type and non-astringent(NA)-type mutants show significant variation in PA accumulation, but the infuencing ... Proanthocyanidins(PAs) are specialized metabolites that infuence persimmon fruit quality.Normal astringent(A)-type and non-astringent(NA)-type mutants show significant variation in PA accumulation, but the infuencing mechanism remains unclear. In this study, among the six identified DTXs/MATEs proteins associated with PA accumulation, we observed that allelic variation and preferential transport by Dk DTX5/MATE5 induced variation in PA accumulation for A-type and NA-type fruit. The expression pattern of Dk DTX5/MATE5 was correlated with PA accumulation in NA-type fruit. Upregulation and downregulation of Dk DTX5/MATE5 promoted and inhibited PA accumulation, respectively, in the NA-type fruit. Interestingly, transporter assays of Xenopus laevis oocytes indicated that Dk DTX5/MATE5 preferentially transported the PA precursors catechin, epicatechin, and epicatechin gallate, resulting in their increased ratios relative to the total PAs, which was the main source of variation in PA accumulation between the A-type and NA-type. The allele lacking Ser-84 in Dk DTX5/MATE5 was identified as a dominantly expressed gene in the A-type and lost its transport function. Site-directed mutagenesis revealed that Dk DTX5/MATE5 binds to PA precursors via Ser-84. These findings clarify the association between the transporter function of Dk DTX5/MATE5 and PA variation, and can contribute to the breeding of new cultivars with improved fruit quality. 展开更多
关键词 astringENCY DTX/MATE persimmon(Diospyros kaki Thunb.) proanthocyanidins(PAs) TONOPLAST TRANSMEMBRANE
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饮片粉碎度对诃子多酚类成分和涩味的影响及机制研究
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作者 陈思情 陈娅玲 +4 位作者 樊习锩 杨璐 杨鑫 吴星熠 韩雪 《中草药》 北大核心 2026年第2期438-447,共10页
目的 通过分析不同粉碎度诃子Chebulae Fructus的多酚类成分、涩味程度、呈涩机制及其内在相关性,为诃子的进一步开发研究奠定基础。方法 将诃子粉碎为6种粒度(原饮片、超大颗粒、大颗粒、中颗粒、小颗粒、细粉)样品,采用HPLC法测定其... 目的 通过分析不同粉碎度诃子Chebulae Fructus的多酚类成分、涩味程度、呈涩机制及其内在相关性,为诃子的进一步开发研究奠定基础。方法 将诃子粉碎为6种粒度(原饮片、超大颗粒、大颗粒、中颗粒、小颗粒、细粉)样品,采用HPLC法测定其中诃黎勒酸、没食子酸、诃子酸、鞣花酸、柯里拉京和1,3,6-三没食子酰葡萄糖含量;通过指纹图谱分析6种粒度诃子样品主要化学成分群的差异。通过视觉模拟评分法(visual analogue scale,VAS)评价样品的涩味强度,并分析粉碎度、多酚成分和涩味强度三者间的相关性,并运用SDS-PAGE技术从蛋白作用层面揭示其呈涩机制。结果 各样品中6种多酚总含量存在明显差异,从高到低顺序为中颗粒>超大颗粒>细粉>大颗粒>小颗粒>原饮片;指纹图谱分析结果显示,6种粒度诃子样品所含的主要化学成分群基本相同。涩味评价结果显示,不同粉碎度可影响涩味程度,涩味程度从高到低排序为细粉>小颗粒>中颗粒>大颗粒>超大颗粒>原饮片。相关性分析表明,没食子酸与柯里拉京的含量变化是关联粉碎度与涩味感知的关键变量。SDS-PAGE分析证实,诃子涩味形成机制在于多酚成分与唾液蛋白的结合,其中细粉表现出最强的蛋白结合能力。结论 粉碎度是调控诃子多酚成分溶出与涩味强度的关键工艺参数。粒径4.75~6.70 mm的中颗粒诃子的多酚成分含量最高,而粒径0.15~0.18 mm细粉样品的涩味最为强烈。将诃子粉碎至中颗粒(4.75~6.70 mm)是平衡多酚类成分溶出与口服依从性的最优策略。该研究可为诃子炮制工艺标准化及产品开发提供关键的科学依据。 展开更多
关键词 诃子 粉碎度 多酚类成分 涩味 相关性 HPLC 诃黎勒酸 没食子酸 诃子酸 鞣花酸 柯里拉京 1 3 6-三没食子酰葡萄糖 SDS-PAGE技术
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求解拟单调变分不等式问题的加速算法研究
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作者 陈欢欢 李耿华 《东莞理工学院学报》 2026年第1期7-13,共7页
在求解拟单调变分不等式问题的算法中,构造了交替加速项,并利用了Armijo线搜索方法。该算法在每次迭代过程中只进行了一次投影,在所需的假设条件下得到了该算法的弱收敛性证明。最后结合数值实验验证了该算法的有效性。
关键词 变分不等式 拟单调 加速算法 收敛性
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名中医米烈汉“宗气为后天之本”学术思想探析
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作者 成路平 王高雷 +4 位作者 杭程 黄倩 严廷巍 李怡 路波 《陕西中医》 2026年第1期86-91,共6页
宗气学说肇始于《黄帝内经》,经历代医家发展渐成体系。米烈汉教授提出“宗气为后天之本”的创新理论,认为宗气是生命动力系统的核心本源,统摄呼吸、循环、运动等多维功能,将“后天之本”从脾胃运化的“物质输入”维度,跃迁至宗气生化... 宗气学说肇始于《黄帝内经》,经历代医家发展渐成体系。米烈汉教授提出“宗气为后天之本”的创新理论,认为宗气是生命动力系统的核心本源,统摄呼吸、循环、运动等多维功能,将“后天之本”从脾胃运化的“物质输入”维度,跃迁至宗气生化的“能量转化”维度,强调宗气汇聚生成于胸中气海,灌注于气街,贯心脉行生气,为全身诸气之宗帅,为生命后天之宗主。设定“培补宗源、益气充宗”“固摄守宗、敛精归海”“疏肝调枢、涤痰畅宗”“破瘀通脉、畅达气街”相关治法,创制米氏抗纤汤等系列方剂,使宗气学说从《内经》的生理概念发展为涵盖病因病机、诊断治疗的系统学说,本文从理论渊源、学术创新、临床应用三方面较为系统地探索分析阐述了米烈汉教授这一学术思想,认为该理论的贡献不仅在于理论创新,更在于构建起传统医学与现代科技对话的桥梁。 展开更多
关键词 宗气 后天之本 培补宗源 益气充宗 固摄守宗 敛精归海
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基于平均矢量角和动态缩减机制的约束多目标进化算法
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作者 鲁宇明 曹龙昊 +1 位作者 董显娟 熊丽娟 《控制与决策》 北大核心 2025年第8期2473-2480,共8页
针对约束多目标进化算法存在难以平衡种群收敛性与多样性的问题,提出一种基于平均矢量角和动态缩减机制的约束多目标进化算法(CMOEA-BAD).该算法设计主种群和辅助种群,它们分别独立进化,以求解原始问题和辅助问题.对于主种群,CMOEA-BAD... 针对约束多目标进化算法存在难以平衡种群收敛性与多样性的问题,提出一种基于平均矢量角和动态缩减机制的约束多目标进化算法(CMOEA-BAD).该算法设计主种群和辅助种群,它们分别独立进化,以求解原始问题和辅助问题.对于主种群,CMOEA-BAD将理想点与最低点的角度信息相结合构成平均矢量角,并将该角度融入约束支配原则进行个体选择,以平衡种群的多样性与收敛性.对于辅助种群,设计一种种群规模动态缩减机制,通过动态地调整辅助种群的规模来降低其在进化过程中所占用的计算资源,以加快算法的收敛速度.为验证所提出算法的性能,将所提出算法在MW和DTLZ测试问题上与PPS、BiCo、NSBiDiCo、MFOSPEA2以及CMOES算法进行比较分析,并应用于实际工程问题中.实验结果表明,所提出算法不仅能够有效平衡种群的收敛性与多样性,还可以显著提高算法的收敛速度.算法整体运行时间缩短了28%,综合性能更优. 展开更多
关键词 多目标优化 约束 矢量角度 动态缩减机制 收敛性 多样性
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中国新质生产力发展水平区域差异、动态演进与收敛性研究
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作者 张建伟 杨琴 久毛措 《河南师范大学学报(自然科学版)》 北大核心 2025年第6期24-36,I0004,I0005,共15页
新质生产力是推动高质量发展的内在要求和重要着力点.构建了“新质劳动者、新质劳动对象和新质劳动资料”的新质生产力评价指标体系,使用熵值法测算了2013-2022年31个省区新质生产力发展指数,并通过Dagum基尼系数及其分解、核密度估计... 新质生产力是推动高质量发展的内在要求和重要着力点.构建了“新质劳动者、新质劳动对象和新质劳动资料”的新质生产力评价指标体系,使用熵值法测算了2013-2022年31个省区新质生产力发展指数,并通过Dagum基尼系数及其分解、核密度估计、σ收敛和β收敛分析了新质生产力的时空演化特征和收敛特征.研究结果表明:(1)新质生产力发展水平呈现出上升的趋势但增长速度慢,区域差异呈现出“东高中平西低”的态势,且区域差异有进一步加大的趋势;区域间差异是新质生产力发展水平区域差异的主要来源.(2)全国层面上新质生产力发展水平有极化现象,但极端值同平均水平的差距呈现出缩小的趋势.仅东部地区无极化现象,中部地区、西部地区均存在极化现象.(3)全国层面、东部地区、中部地区、发达地区、欠发达地区均不存在σ收敛特征,仅西部地区存在σ收敛特征;全国层面存在绝对β收敛和条件β收敛特征,控制变量表现出明显异质性. 展开更多
关键词 新质生产力 区域差异 动态演进 收敛性
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