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Structural Relationships along a Neoarchean Arc-Continent Collision Zone, North China Craton
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作者 WANG Junpeng Timothy KUSKY +4 位作者 WANG Lu Ali POLAT DENG Hao WANG Chen WANG Songjie 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期242-243,共2页
The Archean North China Craton is composed of the Western Block,Eastern Block and the intervening Central Orogenic Belt.A 4-10 km wide and 85 km long tectonic mélange belt informally called the Zanhuang tectonic
关键词 LINE structural relationships along a Neoarchean Arc-Continent Collision Zone North China Craton
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Molecular characteristics and structure–activity relationships of food-derived bioactive peptides 被引量:15
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作者 YANG Fu-jia CHEN Xu +6 位作者 HUANG Mu-chen YANG Qian CAI Xi-xi CHEN Xuan DU Ming HUANG Jian-lian WANG Shao-yun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第9期2313-2332,共20页
Peptides are functional active fragments of proteins which can provide nutrients needed for human growth and development,and they also have unique physiological activity characteristics relative to proteins.Bioactive ... Peptides are functional active fragments of proteins which can provide nutrients needed for human growth and development,and they also have unique physiological activity characteristics relative to proteins.Bioactive peptides contain a great deal of development potential.More specifically,food-derived bioactive peptides have the advantages of a wide variety of sources,unique structures,high efficiency and safety,so they have broad development prospects.This review provides an overview of the current advances regarding the preparation,functional characteristics,and structure–activity relationships of food-derived bioactive peptides.Moreover,the prospects for the future development and application of food-derived bioactive peptides are discussed.This review may provide a better understanding of foodderived bioactive peptides,and some constructive inspirations for further research and applications in the food industry. 展开更多
关键词 food-derived proteins bioactive peptides molecular characteristics structure–activity relationship
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A Quantitative Structure Property Relationship for Prediction of Flash Point of Alkanes Using Molecular Connectivity Indices 被引量:3
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作者 Morteza Atabati Reza Emamalizadeh 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期420-426,共7页
Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecul... Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecular structure without any experimental effort, they provide a simple and straightforward method for property prediction. In this work the flash point of alkanes was modeled by a set of molecular connectivity indices (Х), modified molecular connectivity indices ( ^mХ^v ) and valance molecular connectivity indices ( ^mХ^v ), with ^mХ^v calculated using the hydrogen perturbation. A stepwise Multiple Linear Regression (MLR) method was used to select the best indices. The predicted flash points are in good agreement with the experimental data, with the average absolute deviation 4.3 K. 展开更多
关键词 quantitative structure property relationship flash point molecular connectivity indices hydrogen perturbation ALKANE
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Study on the Quantitative Structure-toxicity Relationships for the Selected Esters by Using Molecular Electronegativity Interaction Vector (MEIV) 被引量:4
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作者 李建凤 廖立敏 王碧 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第9期1225-1232,共8页
The molecular electronegativity interaction vector (MEIV) was used to describe the molecular structure of 30 selected esters. Two excellent QSTR models were built up by using multiple linear regression (MLR) and p... The molecular electronegativity interaction vector (MEIV) was used to describe the molecular structure of 30 selected esters. Two excellent QSTR models were built up by using multiple linear regression (MLR) and partial least-squares regression (PLS). The correlation coefficients (R) of the two models were 0.945 and 0.941, respectively. The models were evaluated by performing the cross validation with the leave-one-out (LOO) procedure. The cross-verification correlation coefficients (RCV) of the two models were 0.921 and 0.919, respectively. The results showed that the models constructed in this work could provide estimation stability and favorable predictive ability. 展开更多
关键词 ESTERS tetrahymena pyriformis half-inhibitory growth concentration (IGC50) structural characterization quantitative structure toxicity relationship (QSTR)
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Tuning Active Metal Atomic Spacing by Filling of Light Atoms and Resulting Reversed Hydrogen Adsorption-Distance Relationship for Efficient Catalysis 被引量:3
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作者 Ding Chen Ruihu Lu +11 位作者 Ruohan Yu Hongyu Zhao Dulan Wu Youtao Yao Kesong Yu Jiawei Zhu Pengxia Ji Zonghua Pu Zongkui Kou Jun Yu Jinsong Wu Shichun Mu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期151-162,共12页
Precisely tuning the spacing of the active centers on the atomic scale is of great significance to improve the catalytic activity and deepen the understanding of the catalytic mechanism,but still remains a challenge.H... Precisely tuning the spacing of the active centers on the atomic scale is of great significance to improve the catalytic activity and deepen the understanding of the catalytic mechanism,but still remains a challenge.Here,we develop a strategy to dilute catalytically active metal interatomic spacing(d_(M-M))with light atoms and discover the unusual adsorption patterns.For example,by elevating the content of boron as interstitial atoms,the atomic spacing of osmium(d_(Os-Os))gradually increases from 2.73 to 2.96?.More importantly,we find that,with the increase in dOs-Os,the hydrogen adsorption-distance relationship is reversed via downshifting d-band states,which breaks the traditional cognition,thereby optimizing the H adsorption and H_2O dissociation on the electrode surface during the catalytic process;this finally leads to a nearly linear increase in hydrogen evolution reaction activity.Namely,the maximum dOs-Os of 2.96?presents the optimal HER activity(8 mV@10 mA cm^(-2))in alkaline media as well as suppressed O adsorption and thus promoted stability.It is believed that this novel atomic-level distance modulation strategy of catalytic sites and the reversed hydrogen adsorption-distance relationship can shew new insights for optimal design of highly efficient catalysts. 展开更多
关键词 ELECTROCATALYSIS DFT calculation Interstitial filling Hydrogen evolution Structure–activity relationships
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Relationship of quantitative structure and pharmacokinetics in fluoroquinolone antibacterials 被引量:2
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作者 Die Cheng Wei-Ren Xu Chang-Xiao Liu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第17期2496-2503,共8页
AIM: To study the relationship between quantitative structure and pharmacokinetics (QSPkR) of fluorocluinolone antibacterials.METHODS: The pharmacokinetic (PK) parameters of oral fluoroquinolones were collected ... AIM: To study the relationship between quantitative structure and pharmacokinetics (QSPkR) of fluorocluinolone antibacterials.METHODS: The pharmacokinetic (PK) parameters of oral fluoroquinolones were collected from the literature. These pharmacokinetic data were averaged, 19 compounds were used as the training set, and 3 served as the test set. Genetic function approximation (GFA) module of Cerius2 software was used in QSPkR analysis.RESULTS: A small volume and large polarizability and surface area of substituents at C-7 contribute to a large area under the curve (AUC) for fluoroquinolones. Large polarizability and small volume of substituents at N-1 contribute to a long half life elimination.CONCLUSION: QSPkR models can contribute to some fluoroquinolones antibacterials with excellent pharmacokinetic properties. 展开更多
关键词 Quantitative structure pharmacokinetic relationship Genetic function approximation Fluoro-quinolones Elimination half life
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Structural Characterization and Octanol/water Partition Coefficients(LogP) Prediction for Oxygen-containing Organic Compounds 被引量:8
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作者 廖立敏 黄茜 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1243-1250,共8页
New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed t... New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed to build two relationship models between the structures and octanol/water partition coefficients(LogP) of the compounds. The modeling correlation coefficients(R) were 0.976 and 0.922, and the "leave one out" cross validation correlation coefficients(R(CV)) were 0.973 and 0.909, respectively. The results showed that the structural descriptors could well characterize the molecular structures of the compounds; the stability and predictive power of the models were good. 展开更多
关键词 oxygen-containing organic compounds octanol/water partition coefficients(LogP) structural descriptors relationship between structures and properties
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Structure-activity relationships of oxime compounds as flotation collectors by DFT calculations 被引量:2
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作者 Yu-xi LU Shuai WANG +2 位作者 Zhan-fang CAO Xin MA Hong ZHONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第12期4076-4087,共12页
The relationships between the structure of oxime compounds(R^(1)R^(2)C=NOH,R^(1)/R^(2)=alkyl groups) with different substituents and their corresponding flotation performances were studied. The analyses of density fun... The relationships between the structure of oxime compounds(R^(1)R^(2)C=NOH,R^(1)/R^(2)=alkyl groups) with different substituents and their corresponding flotation performances were studied. The analyses of density functional theory(DFT) calculations illustrated that the introduced phenyl group at the R^(1) position could enhance the acidity,while the heptyl group could effectively increase the hydrophobicity and benefit van der Waals interactions. Meanwhile,the introduced amino group at the R^(2) position could provide cationic sites to interact with negatively charged surfaces of minerals, while the introduced hydroxyl group could provide additional action sites to form stable chelates with metal ions. Based on the structure-activity relationships, structural optimization was carried out to obtain three efficient collectors, which possessed superior flotation separation performances, proving the effectiveness of the structural modification to oxime compounds in this work. 展开更多
关键词 oxime compounds flotation collector DFT calculations structure–reactivity relationship structural modification
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Design strategies and structure‐performance relationships of heterogeneous catalysts for selective hydrogenation of 1,3‐butadiene 被引量:1
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作者 Mengru Wang Yi Wang +2 位作者 Xiaoling Mou Ronghe Lin Yunjie Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第4期1017-1041,共25页
Selective hydrogenation of 1,3‐butadiene is an essential process in the upgrading of the crude C4 cut from the petroleum chemical sector.Catalyst design is crucial to achieve a virtually alkadiene‐free product while... Selective hydrogenation of 1,3‐butadiene is an essential process in the upgrading of the crude C4 cut from the petroleum chemical sector.Catalyst design is crucial to achieve a virtually alkadiene‐free product while avoiding over‐hydrogenating valuable olefins.In addition to the great industrial relevance,this demanding selectivity pattern renders 1,3‐butadiene hydrogenation a widely used model reaction to discriminate selective hydrogenation catalysts in academia.Nonetheless,critical reviews on the catalyst development are extremely lacking in literature.In this review,we aim to provide the reader an in‐depth overview of different catalyst families,particularly the precious metal‐based monometallic catalysts(Pd,Pt,and Au),developed in the last half century.The emphasis is placed on the development of new strategies to design high‐performance architectures,the establishment of structure‐performance relationships,and the reaction and deactivation mechanisms.Thrilling directions for future optimization of catalyst formulations and engineering aspect are also provided. 展开更多
关键词 1 3‐Butadiene Catalyst design Selective hydrogenation Structure‐performance relationship Reaction and deactivation mechanism
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Structural Characterization and Toxicity Prediction of Some Organic Compounds
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作者 廖立敏 李建凤 王碧 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第10期1397-1402,共6页
A new molecular structural characterization(MSC)method called molecular vertexes correlative index(MVCI)was constructed in this paper.The index was used to describe the structures of 45 compounds and a quantitativ... A new molecular structural characterization(MSC)method called molecular vertexes correlative index(MVCI)was constructed in this paper.The index was used to describe the structures of 45 compounds and a quantitative structure-activity relationship(QSAR)model of toxicity(–lgEC50)was obtained through multiple linear regression(MLR)and stepwise multiple regression(SMR).The correlation coefficient(R)of the model was 0.912,and the standard deviation(SD)of the model was 0.525.The estimation stability and prediction ability of the model were strictly analyzed by both internal and external validations.The Leave-One-Out(LOO)Cross-Validation(CV)correlation coefficient(RCV)was 0.816 and the standard deviation(SDCV)was 0.739,respectively.For the external validation,the correlation coefficient(Rtest)was 0.905 and the standard deviation(SDtest)was 0.520,respectively.The results showed that the index was superior in molecular structural representation.The stability and predictability of the model were good. 展开更多
关键词 organic pollutants TOXICITY molecular vertexes correlative index(MVCI) structure descriptors quantitative structure activity relationship(QSAR)
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Structural features of substituted triazole-linked chalcone derivatives as antimalarial activities against D_(10) strains of Plasmodium falciparum: A QSAR approach
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作者 Mukesh C.Sharma 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3738-3744,共7页
A quantitative structure–activity relationship(QSAR) was performed to analyze antimalarial activities against the D10 strains of Plasmodium falciparum of triazole-linked chalcone and dienone hybrid derivatives using ... A quantitative structure–activity relationship(QSAR) was performed to analyze antimalarial activities against the D10 strains of Plasmodium falciparum of triazole-linked chalcone and dienone hybrid derivatives using partial least squares regression coupled with stepwise forward–backward variable selection method. QSAR analyses were performed on the available IC50 D10 strains of Plasmodium falciparum data based on theoretical molecular descriptors. The QSAR model developed gave good predictive correlation coefficient(r2) of 0.8994, significant cross validated correlation coefficient(q2) of 0.7689, r2 for external test set)(2predr of 0.8256, coefficient of correlation of predicted data set)(2sepred,r of 0.3276. The model shows that antimalarial activity is greatly affected by donor and electron-withdrawing substituents. The study implicates that chalcone and dienone rings should have strong donor and electron-withdrawing substituents as they increase the activity of chalcone. Results show that the predictive ability of the model is satisfactory, and it can be used for designing similar group of antimalarial compounds. The findings derived from this analysis along with other molecular modeling studies will be helpful in designing of the new potent antimalarial activity of clinical utility. 展开更多
关键词 quantitative structure–activity relationship(QSAR) CHALCONE ANTIMALARIAL Plasmodium falciparum stepwise forward–backward partial least squares
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Mechanical Properties of Living Adherent Cells :Relationship with Structure and Function
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作者 R. FODIL S. Féréol +3 位作者 E. PLANUS V.M. LAURENT B. LOUIS D. ISABEY 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期9-10,共2页
关键词 relationship with Structure and Function Mechanical Properties of Living Adherent Cells PBM CELL
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Structure - Antimicrobial Activity Relationship Investigation of Some Butadiene and Chalcone Derivatives
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作者 Hanoy AL-Amood Hadeel T.AL-Hadithi Ghazwan F. Fadhil 《Journal of Life Sciences》 2013年第7期705-711,共7页
The biological activity against Staphylococcus aureus, and Eschericia coil were investigated implementing three series, the first series was l-phenyl-2-(4'-X-phenyl)-4-(2,4-dichlorophenyl)-1,3-butadiene, where X ... The biological activity against Staphylococcus aureus, and Eschericia coil were investigated implementing three series, the first series was l-phenyl-2-(4'-X-phenyl)-4-(2,4-dichlorophenyl)-1,3-butadiene, where X = H, CH3, OCH3, NH2, C1, F, NO2 and COOEt; the second was 3,4-dichlorochalcone series namely 3-(3,4-dichlorophenyl)-l-(4'-X-phenyl)-2-propen-l-one, where X = H, CH3, OCH3, NH2, CI, F, NO2 and CN; and the third one was 2,4-dichlorochalcone series namely 3-(2,4-dichlorophenyl)-l- (4'-X-phenyl)-2-propen-l-one, where X = H, CH3, OCH3, NH2, C1, F, NO2 and COOEt. MIC, MBC and the percentage of inhibition (activity) at 20 ~tg/mL, 15 μg/mL and 10μg/mL against Eschericia coli, and at 7.5 lag/mL, 5 μg/mL and 2.5 μg/mL against Staphylococcus aureus, were determined for each compound in the three series. Highest MIC activity against E. coli and S. aureus were given by 2,4-dichlorochalcone series. Butadiene series was similar in behavior to 2,4-dichlorochalcone series in MIC activity against S. aureus. Results of MBC revealed that compounds in the three series exerted high activity against both types of bacteria. Compounds substituted with nitro or nitril exhibited higher activity than other compounds in the three series. Percentage of inhibition of halogenated compounds (4'-C1 and 4'-F) was almost equal in every series. Compounds with substituents (4'-H and 4'-CH3) showed fluctuation in activity according to the nature of each series. 展开更多
关键词 Structure activity relationship CHALCONE butadiene Eschericia coli Staphylococcus aureus.
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PHYLETIC RELATIONSHIP OF PROTEIN STRUCTURES BASED ON SPATIAL PREFERENCE OF RESIDUES
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作者 Chun Xu QU Lu Hun LAI +2 位作者 Xiao Jie XU Xue Mei YUAN You Qi TANG 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第11期867-870,共4页
A distance measure that infers to indicate the evolutionary relationship of protein structures has been developed based on spatial preference factors of residues. The spatial preference factor is a reflection of the e... A distance measure that infers to indicate the evolutionary relationship of protein structures has been developed based on spatial preference factors of residues. The spatial preference factor is a reflection of the environment of residues in tertiary structure. Compared with the phyletic relationships derived from sequence homologies and three-dimensional structures, we find that the two lines of evolution are similar in general. This approach is applied to a group of glins here. 展开更多
关键词 PHYLETIC relationship OF PROTEIN STRUCTURES BASED ON SPATIAL PREFERENCE OF RESIDUES der
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Studies on the Relationship between the Helical Structure and Optical Activity of Some Chiral Cyclic Esters Ⅱ
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作者 Ai Hua NIE Xiu Lin YE Qi Yi XING(Department of Chemistry,Pcking University,Beijing 100871) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第2期141-144,共4页
A method for the analysis of the relationship between the helical structure and optical activity was proposed by the study of the conformations and X-ray diffraction structures of some cyclic esters prepared by esteri... A method for the analysis of the relationship between the helical structure and optical activity was proposed by the study of the conformations and X-ray diffraction structures of some cyclic esters prepared by esterification of L-(-)-2.3-O-methylidene threitol and L-(+)-2,3-O-isopropplidene threitol with alkanedioyl dichlorides and o-,m-,and p-phthaloyl dichlorides. 展开更多
关键词 Activity CL Studies on the relationship between the Helical Structure and Optical Activity of Some Chiral Cyclic Esters
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IndRT-GCNets: Knowledge Reasoning with Independent Recurrent Temporal Graph Convolutional Representations
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作者 Yajing Ma Gulila Altenbek Yingxia Yu 《Computers, Materials & Continua》 SCIE EI 2024年第1期695-712,共18页
Due to the structural dependencies among concurrent events in the knowledge graph and the substantial amount of sequential correlation information carried by temporally adjacent events,we propose an Independent Recurr... Due to the structural dependencies among concurrent events in the knowledge graph and the substantial amount of sequential correlation information carried by temporally adjacent events,we propose an Independent Recurrent Temporal Graph Convolution Networks(IndRT-GCNets)framework to efficiently and accurately capture event attribute information.The framework models the knowledge graph sequences to learn the evolutionary represen-tations of entities and relations within each period.Firstly,by utilizing the temporal graph convolution module in the evolutionary representation unit,the framework captures the structural dependency relationships within the knowledge graph in each period.Meanwhile,to achieve better event representation and establish effective correlations,an independent recurrent neural network is employed to implement auto-regressive modeling.Furthermore,static attributes of entities in the entity-relation events are constrained andmerged using a static graph constraint to obtain optimal entity representations.Finally,the evolution of entity and relation representations is utilized to predict events in the next subsequent step.On multiple real-world datasets such as Freebase13(FB13),Freebase 15k(FB15K),WordNet11(WN11),WordNet18(WN18),FB15K-237,WN18RR,YAGO3-10,and Nell-995,the results of multiple evaluation indicators show that our proposed IndRT-GCNets framework outperforms most existing models on knowledge reasoning tasks,which validates the effectiveness and robustness. 展开更多
关键词 Knowledge reasoning entity and relation representation structural dependency relationship evolutionary representation temporal graph convolution
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The Study of the Effect of Educational Level of Students and English Language Teachers' Awareness on True and False Cognates in Iran
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作者 Javad Gholami Parviz Alavinia Siros Izadpanah 《Sino-US English Teaching》 2015年第7期471-478,共8页
The ability to speak two languages in the non-English-speaking countries is a remarkable achievement. There is a good reason to believe that bilingualism is the norm for the majority of people in the world, because 70... The ability to speak two languages in the non-English-speaking countries is a remarkable achievement. There is a good reason to believe that bilingualism is the norm for the majority of people in the world, because 70% of the earth's population are supposed to be bilingual or multilingual. Our purpose of the study was to determine the participants' awareness of using true and false cognate words of L 1 (the first language) & L2 (the second language) in learning English. Three hundred and eighty-five selected people from 3,789 statistical population participated in 2014--2015 at three levels of A.D., B.A., and M.A. of Islamic Azad University as well as teachers of English in English educational institutions in Zanjan (Iran). Each educational level was considered as one category with the total sample calculated by using Kokran Formula, and the amount of each category was determined by using appropriate proportion and randomized categorical sampling method. The participants' age was between from 18 to 52, with a mean age of 29 years. The materials were 45 words of true and false cognate's words from 500 words by doing CVR (content validity ratio) and CVI (content validity index) (Lawshe's table with the index of 88% and 82% respectively) for being reliable and valid. ANOVA (Analysis of variance) was used for studying the effect of educational level on the rate of awareness. In other words, the awareness level has been compared in different educational levels. The results of Dankan test show that: There is no significant difference between the awareness of A.D., B.A., and M.A. levels, but there is a significant difference between the level of awareness of teachers group and the other groups (in true cognate words) and for false cognate words, there is no significant difference between the level of awareness of the four groups in this regard. 展开更多
关键词 AWARENESS educational level false and true cognate words L2 structural relationship
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The Use of Cognate Words and Interlingual Homographs to Investigate the Cross-Linguistics in Second Language Processing in Iran
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作者 Javad Gholami Parviz Alavinia SirosIzadpanah 《Sino-US English Teaching》 2015年第6期448-456,共9页
Various investigations have shown that the native language impacts foreign word recognition and this influence is adapted by the dexterity in the normative language. Cognates, words which area like beyond two or addit... Various investigations have shown that the native language impacts foreign word recognition and this influence is adapted by the dexterity in the normative language. Cognates, words which area like beyond two or additional languages in some fields signify an attention-grabbing, illuminating, and crucial facet of foreign or second language learning and research. Forty-five (males and females) participants have been randomly chosen and participated in the experiment in Islamic Azad University, Zanjan, Iran, in 2014-2015 school year. The participants' age was between from 18 to 28, with a mean age of 21.5 years. The materials were divided into two groups which include 30 true cognates and 30 false cognates words from 300 words by doing CVR (content validity ratio) and CVI (content validity index) (Lawshe's table with index of 88% and 82% respectively) for being reliable and valid. These words have been taught to them, after a week, a test has been prepared about those words. According to the results of T-test for comparing the average marks of learning in every two groups can be said that there is a meaningful difference between the scores. The results show that the students learned true cognate words better than the false cognate words. The results of this investigation conjointly make sure the expectations that cognate-based instruction can absolutely impact in second language acquisition. 展开更多
关键词 false and true cognates L2 structural relationship second language vocabulary acquisition teaching through cognates
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Application of TLSER method in predicting the aqueous solubility and n-octanol/water partition coefficient of PCBs,PCDDs and PCDFs 被引量:12
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作者 HUANGJun YUGang +3 位作者 ZHANGZu-lin WANGYi-lei ZHUWei-hua WUGuo-shi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期21-29,共9页
The theoretical linear solvation energy relationship(TLSER) approach was adopted to predict the aqueous solubility and n -octanol/water partition coefficient of three groups of environmentally important chemicals-poly... The theoretical linear solvation energy relationship(TLSER) approach was adopted to predict the aqueous solubility and n -octanol/water partition coefficient of three groups of environmentally important chemicals-polychlorinated biphenyls(PCBs), polychlorinated dibenzodioxins and dibenzofurans(PCDDs and PCDFs). For each compound, five quantum parameters were calculated using AM1 semiempirical molecular orbital methods and used as structure descriptors: average molecular polarizability(α), energy of the lowest unoccupied molecular orbit( E _ LUMO ), energy of the highest occupied molecular orbit( E _ HOMO ), the most positive charge on a hydrogen atom( q _+), and the most negative atomic partial charge( q _-) in the solute molecule. Then standard independent variables in TLSER equation was extracted and two series of quantitative equations between these quantum parameters and aqueous solubility and n -octanol/water partition coefficient were obtained by stepwise multiple linear regression(MLR) method. The developed equations have both quite high accuracy and explicit meanings. And the cross-validation test illustrated the good predictive power and stability of the established models. The results showed that TLSER could be used as a promising approach in the estimation of partition and solubility properties of macromolecular chemicals, such as persistent organic pollutants. 展开更多
关键词 persistent organic pollutants(POPs) quantitative structure property relationship(QSPR) theoretical linear solvation energy relationship(TLSER) polychlorinated biphenyls (PCBs) polychlorinated dibenzo- p -dioxins(PCDDs) polychlorinated di
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Effect of the structure of ginsenosides on the in vivo fate of their liposomes 被引量:6
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作者 Chen Chen Jiaxuan Xia +5 位作者 Hongwei Ren Anni Wang Ying Zhu Ru Zhang Zicheng Gan Jianxin Wang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2022年第2期219-229,共11页
To utilize themultiple functions and give full play of ginsenosides,a variety of ginsenosides with different structures were prepared into liposomes and evaluated for their effect on the stability,pharmacokinetics and... To utilize themultiple functions and give full play of ginsenosides,a variety of ginsenosides with different structures were prepared into liposomes and evaluated for their effect on the stability,pharmacokinetics and tumor targeting capability of liposomes.The results showed that the position and number of glycosyl groups of ginsenosides have significant effect on the in vitro and in vivo properties of their liposomes.The pharmacokinetics of ginsenosides liposomes indicated that the C-3 sugar group of ginsenosides is beneficial to their liposomes for longer circulation in vivo.The C-3 and C-6 glycosyls can enhance the uptake of their liposomes by 4T1 cells,and the glycosyls at C-3 position can enhance the tumor active targeting ability significantly,based on the specific binding capacity to Glut 1 expressed on the surface of 4T1 cells.According to the results in the study,ginsenoside Rg3 and ginsenoside Rh2 are potential for exploiting novel liposomes because of their cholesterol substitution,long blood circulation and tumor targeting capabilities.The results provide a theoretical basis for further development of ginsenoside based liposome delivery systems. 展开更多
关键词 GINSENOSIDES Liposomes Structure activity relationship Rg3 liposomes Long circulation Tumor targeting Glut 1
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