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Synergistic effects of three traditional herbs green tea,mulberry leaf and corn silk on glucose uptake level of L6 myoblasts and the hypoglycemic mechanism
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作者 Jing-Na Zhou Ming-Yue Li +4 位作者 Ting-Ting Zhang Jing-Yang Lu Min Zhang Peng-Wei Zhuang Hai-Xia Chen 《Traditional Medicine Research》 2024年第7期1-12,共12页
Background:Green tea,mulberry leaf and corn silk are traditional herbs used in the prevention and treatment of diabetes in China for a long time,but their synergistic hypoglycemic effects and mechanisms remain unclear... Background:Green tea,mulberry leaf and corn silk are traditional herbs used in the prevention and treatment of diabetes in China for a long time,but their synergistic hypoglycemic effects and mechanisms remain unclear.Methods:The effective components of green tea,mulberry leaf and corn silk were extracted and enriched.Mixture design of experiments was used to study the influences of different combinations on the cell viability and glucose uptake level of L6 myoblasts,so as to determine the optimal synergistic hypoglycemic combination.The possible hypoglycemic mechanism of the optimal synergistic combination was explored by cytotoxicity assay,glucose uptake assay,and western blot.Results:Three polyphenol enrichment fractions of the herbs,30%ethanol elution fraction of green tea(GT),50%ethanol elution fraction of mulberry leaf(ML)and 60%ethanol elution fraction of corn silk(CS)were obtained.The antioxidant activities of GT-30%,ML-50%and CS-60%were superior to those of crude extracts,and showed strong potential inα-amylase andα-glucosidase inhibition activities.The optimal synergistic combination of crude extracts G7(crude extract of green tea:crude extract of mulberry leaf:crude extract of corn silk=1:5:3),polyphenol enrichment fractions R3(GT-30%:ML-50%:CS-60%=1:7:1)and monomers X2(epigallocatechin gallate:morusin:formononetin=3:1:2)were selected,respectively.G7,R3,and X2 showed promoting effects on the cell viability and glucose uptake of L6 myoblasts within the detected concentration range.In addition,G7,R3,and X2 could increase the expression levels of p-PI3K/PI3K and p-Akt/Akt in L6 myoblasts,and promote the translocation of Glut4,but G7 and R3 showed more significant effects.Conclusion:The synergistic hypoglycemic effects of green tea,mulberry leaf and corn silk had the characteristics of multiple-components and multiple-targets with p-PI3K/PI3K,p-Akt/Akt and the translocation of Glut4 signal pathways involved.The three traditional herbs might have the potential to be combined used for the prevention and treatment of diabetes based on the synergistic hypoglycemic effects. 展开更多
关键词 green tea mulberry leaf corn silk synergistic effect type 2 diabetes mellitus mechanism
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Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect
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作者 CHENG Yun SONG Zhanping +2 位作者 XU Zhiwei YANG Tengtian TIAN Xiaoxu 《Journal of Mountain Science》 SCIE CSCD 2024年第3期1058-1074,共17页
The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and tempora... The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass. 展开更多
关键词 Hard siltstone Failure mechanism Stratification effect Infrared radiation characteristic Temporal-damage mechanism DISSIMILATION
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Rock mechanical characteristics and landscape evolutionary mechanism of the slit-type Danxia landform on the Chinese Loess Plateau
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作者 MEN Huan DING Hua +5 位作者 DENG Yahong MU Huandong HE Nainan SUN Pushuo LI Zhixu LIU Yan 《Journal of Arid Land》 SCIE CSCD 2024年第10期1327-1343,共17页
Since 2015,the newly discovered slit-type Danxia landform on the Chinese Loess Plateau has become a hot topic in the field of geomorphology worldwide.However,the relationships among its formation,evolutionary mechanis... Since 2015,the newly discovered slit-type Danxia landform on the Chinese Loess Plateau has become a hot topic in the field of geomorphology worldwide.However,the relationships among its formation,evolutionary mechanism,and mechanical characteristics of its strata and rocks are not clear.In this paper,the Ganquan canyon group is used as the research object.Basic physical and mechanical indices of sandstone in the Ganquan canyon group were measured through field investigation and indoor experiments,and the deterioration trends for the mechanical parameters of sandstone in this area under the action of infiltration,acid dry-wet cycles,and freeze-thaw cycles were revealed.Lastly,the formation and evolutionary mechanism of the slit-type Danxia landform were discussed.The results showed that:(1)The sandstone in the canyon group had a low cementation degree and weak cohesive force,which was easily weakened under the action of water,resulting in a decrease in compressive strength and elastic modulus.(2)Acidic dry-wet cycles caused the mineral composition of the sandstone to be dissolved,and the micropores continued to grow and develop until new cracks were produced.Macroscopically,the compressive strength and elastic modulus of sandstone were greatly reduced,and this damage was cumulative and staged.The greater the acidity,the greater the damage.(3)As the number of freeze-thaw cycles increased,the uniaxial compressive strength and elastic modulus of the sandstone decreased continuously.During the freeze-thaw cycle process,the growth and development of cracks were primarily in fracture mode and usually developed along parallel bedding positions.(4)The interaction of tectonic activity and lithology with different weathering processes was a key factor in the formation and evolution of the slit-type Danxia landform.In conclusion,the intricate process of weathering influenced by historical climatic fluctuations has been pivotal in shaping the topography of Danxia landform. 展开更多
关键词 landscape-forming rocks mechanical characteristics landscape-forming effects slit-type Danxia landform Loess Plateau
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Theoretical study of kinetic isotope effects for vacancy diffusion of impurity in solids
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作者 Yuxi Jing Xuefang Li Yun Liu 《Acta Geochimica》 EI CAS CSCD 2024年第5期959-970,共12页
Theoretical studies of the diffusionalisotope effect in solids are still stuck in the 1960s and 1970s.With the development of high spatial resolution mass spectrometers,isotopic data of mineral grains are rapidly accu... Theoretical studies of the diffusionalisotope effect in solids are still stuck in the 1960s and 1970s.With the development of high spatial resolution mass spectrometers,isotopic data of mineral grains are rapidly accumulated.To dig up information from these data,molecularlevel theoretical models are urgently needed.Based on the microscopic definition of the diffusion coe fficient(D),a new theoretical framework for calculating the diffusional isotope effect(DIE(v))(intermsofD*/D)forvacancy-mediated impurity diffusion in solids is provided based on statistical mechanics formalism.The newly derived equation shows that theDIE(v)can be easily calculated as long as the vibration frequencies of isotope-substituted solids are obtained.The calculatedDIE(v)values of^(199)Au/^(195)Au and^(60)Co/^(57)Co during diffusion in Cu and Au metals are all within 1%of errors compared to the experimental data,which shows that this theoretical model is reasonable and precise. 展开更多
关键词 Vacancy diffusion Diffusional isotope effect Statistical mechanics
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Inhibitory effect of procyanidin B2 and tannin acid on cholesterol esterase and their synergistic effect with orlistat
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作者 Xiangxin Li Yijing Pu +5 位作者 Haitao Jiang Wenxiao Jiao Wenjun Peng Wenli Tian Weibo Jiang Xiaoming Fang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期360-369,共10页
This study was aimed to analyze the effect of procyanidin B2(PC)and tannin acid(TA)on the activities of cholesterol esterase(CEase)and the inhibitory mechanisms of enzymatic activity.The interaction mechanisms were in... This study was aimed to analyze the effect of procyanidin B2(PC)and tannin acid(TA)on the activities of cholesterol esterase(CEase)and the inhibitory mechanisms of enzymatic activity.The interaction mechanisms were investigated by enzymatic kinetics,multi-spectroscopy methods,thermodynamics analysis,molecular docking,and dynamic simulations.PC and TA could bind with CEase and inhibit the activity of enzyme in a mixed-competitive manner and non-competitive manner,which was verified by molecular docking simulations and dynamics simulations.Also,PC and TA showed the synergistic inhibition with orlistat.Fluorescence,UVvis and the thermodynamic analysis revealed that the complexes were formed from CEase and inhibitors by noncovalent interaction.As revealed by the circular dichroism results,both PC and TA decreased enzymatic activities by altering the conformations of CEase.The inhibition of PC and TA on CEase might be one mechanism for its cholesterol-lowering effect. 展开更多
关键词 Cholesterol esterase POLYPHENOLS Interaction mechanisms Molecular dynamic simulation Synergistic effect
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Influence of the boundary effect on the mechanical response test of pavement cushion under the wetting effect of silt
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作者 Luo Qiqi Yu Qian +3 位作者 Zhang Sheng Ma Xinyan Ye Xinyu Du Yinfei 《Journal of Southeast University(English Edition)》 EI CAS 2024年第3期266-274,共9页
Through a self-developed model test system,the mechanical properties of silt and the deformation characteristics of airport runways were investigated during the period of subgrade wetting.Based on the test results,the... Through a self-developed model test system,the mechanical properties of silt and the deformation characteristics of airport runways were investigated during the period of subgrade wetting.Based on the test results,the reliability of the numerical simulation results was verified.Numerical models with different sizes were established.Under the same cushion parameter and loading width ranges,the effects of the cushion parameters and loading conditions on the mechanical responses of the cushion before and after subgrade wetting were analyzed.The results show that the internal friction angles of silt with different wetting degrees are approximately 34°.The cohesion is from 8 to 44 kPa,and the elastic modulus is from 15 to 34 MPa.Before and after subgrade wetting,the variation rates of the cushion horizontal tensile stresses with the same cushion parameters and loading width ranges are different under the influence of boundary effects.After subgrade wetting,the difference in the variation rates of the cushion horizontal tensile stresses under the same cushion parameter range decreases compared with that before subgrade wetting;however,this difference increases under the same loading width range.Before and after subgrade wetting,the influence of the boundary effect on the mechanical response evaluation of the cushion is not beneficial for optimizing the pavement design parameters.When the cushion thickness is more than 0.25 m,the influence of the boundary effect can be disregarded. 展开更多
关键词 pavement cushion silt subgrade WETTING boundary effect mechanical response
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Unraveling the Stray Current-Induced Interfacial Transition Zone(ITZ)Effect on Sulfate Corrosion in Concrete
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作者 Yong-Qing Chen Lin-Ya Liu +3 位作者 Da-Wei Huang Qing-Song Feng Ren-Peng Chen Xin Kang 《Engineering》 SCIE EI CAS CSCD 2024年第10期130-152,共23页
The rail transit in sulfate-rich areas faces the combined effects of stray current and salt corrosion;however,the sulfate ion transport and concrete degradation mechanisms under such conditions are still unclear.To ad... The rail transit in sulfate-rich areas faces the combined effects of stray current and salt corrosion;however,the sulfate ion transport and concrete degradation mechanisms under such conditions are still unclear.To address this issue,novel sulfate transport and mesoscale splitting tests were designed,with a focus on considering the differences between the interfacial transition zone(ITZ)and cement matrix.Under the influence of stray current,the ITZ played a pivotal role in regulating the transport and mechanical failure processes of sulfate attack,while the tortuous and blocking effects of aggregates almost disappeared.This phenomenon was termed the“stray current-induced ITZ effect.”The experimental data revealed that the difference in sulfate ion transport attributed to the ITZ ranged from 1.90 to 2.31 times,while the difference in splitting strength ranged from 1.56 to 1.64 times.Through the real-time synchronization of splitting experiments and microsecond-responsive particle image velocimetry(PIV)technology,the mechanical properties were exposed to the consequences of the stray currentinduced ITZ effect.The number of splitting cracks in the concrete increased,rather than along the central axis,which was significantly different from the conditions without stray current and the ideal Brazilian disk test.Furthermore,a sulfate ion mass transfer model that incorporates reactivity and electrodiffusion was meticulously constructed.The embedded finite element calculation exhibited excellent agreement with the experimental results,indicating its reliability and accuracy.Additionally,the stress field was determined utilizing analytical methods,and the mechanism underlying crack propagation was successfully obtained.Compared to the cement matrix,a stray current led to more sulfates,more microstructure degradation,and greater increases in thickness and porosity in the ITZ,which was considered to be the essence of the stray current-induced ITZ effect. 展开更多
关键词 Interfacial transition zone(ITZ)effect Stray current Sulfate attack Transport mechanism Splitting test MICROSTRUCTURE
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Exploring the mechanism of active ingredients of Smilacis Glabrae Rhizoma in treating migraine headache through network pharmacology and animal experiments
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作者 Dao-Xian Shu Yan-Yan Chen +3 位作者 Jiao-Rong Wang Ying Wang Yong-Fang Gu Yan-Xin Wang 《Integrative Medicine Discovery》 2024年第18期1-10,共10页
Background:To explore the potential mechanism of action of the active ingredients of Smilacis Glabrae Rhizoma(SGR)in the treatment of migraine using network pharmacology and in vivo experiments.Methods:Through the sea... Background:To explore the potential mechanism of action of the active ingredients of Smilacis Glabrae Rhizoma(SGR)in the treatment of migraine using network pharmacology and in vivo experiments.Methods:Through the search of Traditional Chinese Medicines Systems Pharmacology Database and Analysis Platform,Genecards,Drugbank and other databases,we obtained active ingredients,targets of SGR and related disease targets of migraine,and took the intersection for protein-protein interactions analysis.After constructing the network diagram,network topology analysis was performed to derive the core targets and key active ingredients,and Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed.Finally,molecular docking was performed and validated by in vivo experiments.In vivo experiments,18 male BALB/c mice were selected,and the SGR group was fed with SGR drinking tablet concentrate,and nitroglycerin injection was used to construct a mouse model of migraine.Enzyme-linked immunosorbent assay test was used to detect the levels of TNF-α,IL-1β,IL-6,and AKT1 in plasma.Results:The results showed that the core targets of SGR for the treatment of migraine were TNF-α,IL-1β,IL-6,and AKT1.These core targets and key active ingredients had better binding ability.Compared with the blank group,the number of head scratching in the model group increased.Compared with the model group,there was a significant reduction of the number of head scratching in the SGR group.In comparison with the blank group,the protein level in the plasma in the model group was markedly higher.Compared with the model group,the protein level in the SGR group was significantly lower.Conclusion:SGR has the characteristics of improving migraine based on multi-targets,multi-components and multi-pathways,and the mechanism of action may be related to the inhibition of the release of inflammatory factors,neuron protection,and interference with apoptosis and other processes. 展开更多
关键词 MIGRAINE Smilacis Glabrae Rhizoma network pharmacology molecular docking mechanism of effect
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Screening hepatoprotective effective components of Lonicerae japonica Flos based on the spectrum-effect relationship and its mechanism exploring 被引量:1
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作者 Song Wang Lin Yang +4 位作者 Ajiao Hou Songtao Liu Liu Yang Haixue Kuang Hai Jiang 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期283-294,共12页
Lonicerae japonicae Flos(LF)is a kind of healthcare food with hepatoprotective function.This study was designed to explore the spectrum-effect relationships between UPLC fingerprints and the hepatoprotective effects o... Lonicerae japonicae Flos(LF)is a kind of healthcare food with hepatoprotective function.This study was designed to explore the spectrum-effect relationships between UPLC fingerprints and the hepatoprotective effects of LF.Fingerprints of ten batches of LF were established by UPLC-PDA.The inhibitory levels of AST and ALT were used as pharmacological indexes,and secoxyloganin,isochlorogenic acid A and isochlorogenic acid C were screened as hepatoprotective active compounds by grey relational analysis(GRA)and partial least squares regression analysis(PLSR).Caspase-3 was obtained by network pharmacology as a key target of hepatoprotective active compounds.Molecular docking is used to explore the interaction between small molecules and proteins.This work provided a general model of the combination of UPLC-PDA and hepatoprotective effect to study the spectrum-effect relationship of LF,which can be used to considerable methods and insight for the fundamental research of the material basis of similar healthcare food. 展开更多
关键词 Lonicerae japonicae Flos Hepatoprotective effect Spectrum-effect relationship Molecular docking mechanism
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Styrene epoxidation catalyzed by polyoxometalate/quaternary ammonium phase transfer catalysts: The effect of cation size and catalyst deactivation mechanism
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作者 Qiongna Xiao Yuyan Jiang +3 位作者 Weiqiang Yuan Jingjing Chen Haohong Li Huidong Zheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第3期192-201,共10页
Catalytic epoxidation of alkenes is an important type of organic reaction in chemical industry,and the deep insight into catalyst deactivation will help to develop new epoxidation process.In this work,series of quater... Catalytic epoxidation of alkenes is an important type of organic reaction in chemical industry,and the deep insight into catalyst deactivation will help to develop new epoxidation process.In this work,series of quaternary ammoniums bearing different cationic sizes,i.e.MTOA+(methyltrioctylammonium,[(C_(8)H_(17))_(3)CH_(3)N]+),HTMA+(hexadecyltrimethylammonium,[(C_(16)H_(33))(CH_(3))_(3)N]+) and DMDOA+(dimethyldioctadecylammonium,[(C_(18)H_(37))_(2)(CH_(3))_(2)N]+) were incorporated with polyoxometalate (POM) anions to prepare phase transfer catalysts (PTCs),which were used in the styrene epoxidations.Among them,(MTOA)_(3)PW_(4)O_(24)exhibits the best catalytic performance judged from the highest styrene conversion rate(52%) and styrene oxide selectivity (93%),during which the styrene epoxidation conditions were optimized.Meanwhile,the deactivation mechanism of this kind of PTCs was proposed firstly,i.e.in the case of low H_(2)O_(2) content,the oxidant can only be used in the styrene epoxidation,in which the catalyst can transform into stable Keggin-type POM.But when the content of H_(2)O_(2) is higher,the excess H_(2)O_(2) can reactivate the Keggin-type POM into active (PW_(4)O_(24))_(3)-anions,which can trigger the ring-opening polymerization of styrene oxide.Consequently,the catalyst is deactivated by adhered poly(styrene oxide)irreversibly,which was determined by NMR spectra.In this situation,the active moiety{PO_(4)[WO(O_(2))_(2)]_(4)}_(3)-in phase-transfer catalytic system can break into some unidentified species with low W/P ratio with the presence of epoxides.This work will be beneficial for the design of new PTCs in alkene epoxidation in fine chemical industry. 展开更多
关键词 Phosphotungstic acid phase-transfer CATALYST Styrene epoxidation Catalyst deactivation mechanism Cation size effect
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Mechanism of Action and Therapeutic Effect of Modified Qiwei Baishu Powder in Diabetes
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作者 Jinyan Sun Kaiwen Li +1 位作者 Chunyan Sun Shichao Dong 《Journal of Clinical and Nursing Research》 2023年第3期118-123,共6页
Objective:To study the mechanism of action and therapeutic effect of modified Qiwei Baishu powder in diabetic patients.Methods:From January 2021 to January 2022,80 diabetic patients were recruited in our study and div... Objective:To study the mechanism of action and therapeutic effect of modified Qiwei Baishu powder in diabetic patients.Methods:From January 2021 to January 2022,80 diabetic patients were recruited in our study and divided into two groups by the random number table method.Group A was treated with modified Qiwei Baishu powder,whereas group B was treated with western medicine.The therapeutic effect,traditional Chinese medicine(TCM)syndrome score,blood sugar level,and incidence of adverse reaction were compared between the two groups.Result:The therapeutic effect in group A was significantly higher than that in group B(P<0.05);the TCM syndrome scores of group A were significantly lower than those of group B(P<0.05);the fasting blood glucose(FBG),2 hour-postprandial blood glucose(PBG),and glycosylated hemoglobin(HbA1c)levels of group A were significantly lower than those of group B(P<0.05);the incidence of adverse reaction in group A was significantly lower than that in group B(P<0.05).Conclusion:On the basis of western medicine,the addition of modified Qiwei Baishu powder can maintain stable blood sugar levels in patients and alleviate diabetic symptoms;thus,it is not only effective,but also safe for clinical use in diabetes. 展开更多
关键词 DIABETES Modified Qiwei Baishu powder therapeutic effect mechanism of action
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Review on mechanisms and structure-activity relationship of hypoglycemic effects of polysaccharides from natural resources 被引量:5
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作者 Xiaolong Ji Jianhang Guo +3 位作者 Tengzheng Cao Tingting Zhang Yanqi Liu Yizhe Yan 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期1969-1980,共12页
Diabetes mellitus(DM)is a common multifactorial disease,causing various complications,such as chronic metabolism.The current therapies for diabetes mellitus are commercial diabetic drugs that have different definite s... Diabetes mellitus(DM)is a common multifactorial disease,causing various complications,such as chronic metabolism.The current therapies for diabetes mellitus are commercial diabetic drugs that have different definite side effect.However,polysaccharides mainly extracted from natural resources,have advantages of safety,accessibility,and anti-diabetic potential.We have summarized recent research of natural polysaccharides with hypoglycemic activities,focusing on different pharmacological mechanisms in various cell and animal models.The relationships of structure-hypoglycemic effect are also discussed in detail.This review could provide a comprehensive perspective for better understanding on development and mechanism of natural polysaccharides against diabetes mellitus,which have been required by clinical studies yet. 展开更多
关键词 POLYSACCHARIDES Hypoglycemic effect mechanismS Structure-activity relationship
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Size effects on the tensile strength and fracture toughness of granitic rock in different tests 被引量:1
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作者 Ignacio Pérez-Rey Andrea Muñoz-Ibáñez +5 位作者 Manuel A.González-Fernández Mauro Muñiz-Menéndez Miguel Herbón Penabad Xian Estévez-Ventosa Jordi Delgado Leandro RAlejano 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第9期2179-2192,共14页
This study investigates the tensile failure mechanisms in granitic rock samples at different scales by means of different types of tests.To do that,we have selected a granitic rock type and obtained samples of differe... This study investigates the tensile failure mechanisms in granitic rock samples at different scales by means of different types of tests.To do that,we have selected a granitic rock type and obtained samples of different sizes with the diameter ranging from 30 mm to 84 mm.The samples have been subjected to direct tensile strength(DTS)tests,indirect Brazilian tensile strength(BTS)tests and to two fracture toughness testing approaches.Whereas DTS and fracture toughness were found to consistently grow with sample size,this trend was not clearly identified for BTS,where after an initial grow,a plateau of results was observed.This is a rather complete database of tensile related properties of a single rock type.Even if similar databases are rare,the obtained trends are generally consistent with previous scatter and partial experimental programs.However,different observations apply to different types of rocks and experimental approaches.The differences in variability and mean values of the measured parameters at different scales are critically analysed based on the heterogeneity,granular structure and fracture mechanics approaches.Some potential relations between parameters are revised and an indication is given on potential sample sizes for obtaining reliable results.Extending this database with different types of rocks is thought to be convenient to advance towards a better understanding of the tensile strength of rock materials. 展开更多
关键词 Size effect Tensile strength Fracture toughness GRANITE Finite fracture mechanics
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Analysis of displacement damage effects on the charge-coupled device induced by neutrons at Back-n in the China Spallation Neutron Source 被引量:1
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作者 薛院院 王祖军 +9 位作者 陈伟 郭晓强 姚志斌 何宝平 聂栩 赖善坤 黄港 盛江坤 马武英 缑石龙 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期435-442,共8页
Displacement damage effects on the charge-coupled device(CCD)induced by neutrons at the back-streaming white neutron source(Back-n)in the China Spallation Neutron Source(CSNS)are analyzed according to an online irradi... Displacement damage effects on the charge-coupled device(CCD)induced by neutrons at the back-streaming white neutron source(Back-n)in the China Spallation Neutron Source(CSNS)are analyzed according to an online irradiation experiment.The hot pixels,random telegraph signal(RTS),mean dark signal,dark current and dark signal non-uniformity(DSNU)induced by Back-n are presented.The dark current is calculated according to the mean dark signal at various integration times.The single-particle displacement damage and transient response are also observed based on the online measurement data.The trends of hot pixels,mean dark signal,DSNU and RTS degradation are related to the integration time and irradiation fluence.The mean dark signal,dark current and DSNU2 are nearly linear with neutron irradiation fluence when nearly all the pixels do not reach saturation.In addition,the mechanisms of the displacement damage effects on the CCD are demonstrated by combining the experimental results and technology computer-aided design(TCAD)simulation.Radiation-induced traps in the space charge region of the CCD will act as generation/recombination centers of electron-hole pairs,leading to an increase in the dark signal. 展开更多
关键词 displacement damage effects charge-coupled device(CCD) China Spallation Neutron Source(CSNS) mechanismS technology computer-aided design(TCAD)
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The mechanism underlying overwintering death in poplar:the cumulative effect of effective freeze-thaw damage 被引量:4
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作者 Chengchao Yang Jiandong Peng +3 位作者 Xiaoyu Li Dejun Liang Zhiyan Yang Yan Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期219-229,共11页
We analyzed the relationships linking overwintering death and frost cracking to temperature and sunlight as well as the effects of low temperatures and freeze–thaw cycles on bud-burst rates,relative electrical conduc... We analyzed the relationships linking overwintering death and frost cracking to temperature and sunlight as well as the effects of low temperatures and freeze–thaw cycles on bud-burst rates,relative electrical conductivity,and phloem and cambial ultrastructures of poplar.Overwintering death rates of poplar were not correlated with negative accumulated temperature or winter minimum temperature.Freeze–thaw cycles caused more bud damage than constant exposure to low temperatures.Resistance to freeze–thaw cycles differed among clones,and the budburst rate decreased with increasing exposure to freeze–thaw cycles.Cold-resistant clones had the lowest relative electrical conductivity.Chloroplasts exhibited the fastest and the most obvious reaction to freeze–thaw damage,whereas a single freeze–thaw cycle caused little damage to cambium ultrastructure.Several such cycles resulted in damage to plasma membranes,severe damage to organelles,dehydration of cells and cell death.We conclude that overwintering death of poplar is mainly attributed to the accumulation of effective freeze–thaw damage beyond the limits of freeze–thaw resistance. 展开更多
关键词 effective freeze–thaw Freeze–thaw resistance mechanism Overwintering death POPULUS Ultrastructure
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Research progress on chemopreventive effects of phytochemicals on colorectal cancer and their mechanisms 被引量:2
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作者 Teng-Fei Yin Min Wang +2 位作者 Ying Qing Ying-Min Lin Dong Wu 《World Journal of Gastroenterology》 SCIE CAS 2016年第31期7058-7068,共11页
Colorectal cancer(CRC) is a type of cancer with high morbidity and mortality rates worldwide and has become a global health problem. The conventional radiotherapy and chemotherapy regimen for CRC not only has a low cu... Colorectal cancer(CRC) is a type of cancer with high morbidity and mortality rates worldwide and has become a global health problem. The conventional radiotherapy and chemotherapy regimen for CRC not only has a low cure rate but also causes side effects. Many studies have shown that adequate intake of fruits and vegetables in the diet may have a protective effect on CRC occurrence, possibly due to the special biological protective effect of the phytochemicals in these foods. Numerous in vitro and in vivo studies have demonstrated that phytochemicals play strong antioxidant, anti-inflammatory and anti-cancer roles by regulating specific signaling pathways and molecular markers to inhibit the occurrence and development of CRC. This review summarizes the progress on CRC prevention using the phytochemicals sulforaphane, curcumin and resveratrol, and elaborates on the specific underlying mechanisms. Thus, we believe that phytochemicals might provide a novel therapeutic approach for CRC prevention, but future clinical studies are needed to confirm the specific preventive effect of phytochemicals on cancer. 展开更多
关键词 PHYTOCHEMICALS SULFORAPHANE CURCUMIN RESVERATROL Colorectal cancer CHEMOPREVENTIVE effects Molecular mechanism
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Classic mechanisms and experimental models for the anti-inflammatory effect of traditional Chinese medicine 被引量:10
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作者 Du Hongzhi Hou Xiaoying +4 位作者 Guo Yujie Chen Le Miao Yuhuan Liu Dahui Huang Luqi 《Animal Models and Experimental Medicine》 CSCD 2022年第2期108-119,共12页
Inflammation is a common disease involved in the pathogenesis,complications,and sequelae of a large number of related diseases,and therefore considerable research has been directed toward developing anti-inflammatory ... Inflammation is a common disease involved in the pathogenesis,complications,and sequelae of a large number of related diseases,and therefore considerable research has been directed toward developing anti-inflammatory drugs for the prevention and treatment of these diseases.Traditional Chinese medicine(TCM)has been used to treat inflammatory and related diseases since ancient times.According to the re-view of abundant modern scientific researches,it is suggested that TCM exhibit anti-inflammatory effects at different levels,and via multiple pathways with various targets,and recently a series of in vitro and in vivo anti-inflammatory models have been developed for anti-inflammation research in TCM.Currently,the reported classic mechanisms of TCM and experimental models of its anti-inflammatory effects pro-vide reference points and guidance for further research and development of TCM.Importantly,the research clearly confirms that TCM is now and will continue to be an effective form of treatment for many types of inflammation and inflammation-related diseases. 展开更多
关键词 anti-inflammatory effect inflammation and related diseases the classical mechanisms the experimental models traditional Chinese medicine
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Role of methoxy and C_(α)-based substituents in electrochemical oxidation mechanisms and bond cleavage selectivity of β-O-4 lignin model compounds 被引量:1
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作者 Yang Zhou Qiang Zeng +3 位作者 Hongyan He Kejia Wu Fuqiao Liu Xuehui Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期114-125,共12页
In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl gro... In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations. 展开更多
关键词 Lignin model compounds β-O-4 dimers Electrochemical oxidation Oxidation mechanisms Substituent effect
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Analytical solutions for the restraint effect of isolation piles against tunneling-induced vertical ground displacements
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作者 Liqiang Cao Xiangsheng Chen +3 位作者 Xing-Tao Lin Dong Su Huangcheng Fang Dechun Lu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第10期2582-2596,共15页
This paper presents a simplified elastic continuum method for calculating the restraint effect of isolation piles on tunneling-induced vertical ground displacement,which can consider not only the relative sliding of t... This paper presents a simplified elastic continuum method for calculating the restraint effect of isolation piles on tunneling-induced vertical ground displacement,which can consider not only the relative sliding of the pile‒soil interface but also the pile rowesoil interaction.The proposed method is verified by comparisons with existing theoretical methods,including the boundary element method and the elastic foundation method.The results reveal the restraining mechanism of the isolation piles on vertical ground displacements due to tunneling,i.e.the positive and negative restraint effects exerted by the isolation piles jointly drive the ground vertical displacement along the depth direction from the original tunneling-induced nonlinear variation situation to a relatively uniform situation.The results also indicate that the stiffness of the pile‒soil interface,including the pile shaft‒surrounding soil interface and pile tip-supporting soil interface,describes the strength of the pile‒soil interaction.The pile rows can confine the vertical ground displacement caused by the tunnel excavation to the inner side of the isolation piles and effectively prevent the vertical ground displacement from expanding further toward the outer side of the isolation piles. 展开更多
关键词 Restraining mechanism Restraint effect Isolation piles Ground displacement TUNNELING
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Mechanisms on Correlation between the Pericardium Meridian and Heart Effects of Electroacupuncture at Neiguan and Other Acupo 被引量:1
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作者 Cao Qingshu Liu Junling +2 位作者 Wen Shen Liu Rutting Zhuang Ding(Institute of Acupuncture and Moxibustion, China Academyof Traditional Chinese Medicine, Beijing 100700) 《中国针灸》 CAS CSCD 北大核心 1995年第S2期242-243,共2页
MechanismsonCorrelationbetweenthePericardiumMeridianandHeartEffectsofElectroacupunctureatNeiguanandOtherAcup... MechanismsonCorrelationbetweenthePericardiumMeridianandHeartEffectsofElectroacupunctureatNeiguanandOtherAcupointsonAcuteMyoca... 展开更多
关键词 Acupo effects HEART mechanismS MERIDIAN NEIGUAN OtheR PERICARDIUM and at
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