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Activity Screening Study on the Anti-tumor Effects of Extracts from Mahoniae caulis
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作者 Xin XIE Liyuan LI +2 位作者 Aipeng LI Zhidong LEI Suoyi HUANG 《Medicinal Plant》 2023年第6期19-21,26,共4页
[Objectives]To explore the anti-tumor activity of the extracts of petroleum ether,ethyl acetate,n-butanol and aqueous solution from Mahoniae caulis.[Methods]The extracts were extracted with petroleum ether,ethyl aceta... [Objectives]To explore the anti-tumor activity of the extracts of petroleum ether,ethyl acetate,n-butanol and aqueous solution from Mahoniae caulis.[Methods]The extracts were extracted with petroleum ether,ethyl acetate,n-butanol and aqueous solution respectively,and then concentrated.The inhibitory effects of these extracts on the growth of three tumor cell lines in vitro were detected by CCK-8 method,and the IC 50 value was calculated.[Results]The four extracts inhibited the growth of the three tumor cell lines in vitro,among which the n-butanol extract had the best anti-tumor activity.The IC 50 values of the n-butanol extract on human gastric cancer(SGC-7901),human breast cancer(MCF-7)and human liver cancer(BEL-7404)cell lines were 0.23,0.25 and 0.58 mg/mL,respectively.[Conclusions]The ethanol extract of Mahoniae caulis under petroleum ether,ethyl acetate,n-butanol and aqueous solution had certain anti-tumor effect,and n-butanol extract had the best anti-tumor activity. 展开更多
关键词 Mahoniae caulis Tumor cells anti-tumor effects Activity screening
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Research Progress in Anti-tumor Effects of Traditional Chinese Medicine and Its Extracts
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作者 Jingjing LIAO Hong LEI +3 位作者 Liting LAI Bing QING Wen ZHONG Yunli TANG 《Medicinal Plant》 CAS 2023年第5期97-100,共4页
Traditional Chinese medicine and its extracts have received widespread attention due to their significant anti-tumor effects and low adverse reactions.Many traditional Chinese medicine and its extracts have been appli... Traditional Chinese medicine and its extracts have received widespread attention due to their significant anti-tumor effects and low adverse reactions.Many traditional Chinese medicine and its extracts have been applied in clinical tumor treatment.In this paper,the research progress in anti-tumor effects of plant-based traditional Chinese medicine and its extracts,animal-based traditional Chinese medicine and its extracts,and traditional Chinese medicine compound is reviewed. 展开更多
关键词 Traditional Chinese medicine TUMOR anti-tumor mechanism
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Anti-tumor effects induced by gene vaccines co-expressing truncated human prostate specific membrane antigen gene and mouse 4-1BBL
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作者 匡幼林 《外科研究与新技术》 2011年第4期250-250,共1页
Objective To investigate the influence of m4-1BBL on anti-tumor effects induced by truncated human prostate specific membrane antigen ( tPSMA ) gene in mice. Methods A eukaryotic expression plasmid encoding tPSMA and ... Objective To investigate the influence of m4-1BBL on anti-tumor effects induced by truncated human prostate specific membrane antigen ( tPSMA ) gene in mice. Methods A eukaryotic expression plasmid encoding tPSMA and m4-1BBL ( pDC316-tPSMA-IRES m4-1BBL) ,pDC316-tPSMA and pDC316 were constructed. 展开更多
关键词 GENE anti-tumor effects induced by gene vaccines co-expressing truncated human prostate specific membrane antigen gene and mouse 4-1BBL IRES
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Anti-tumor effects of p53N15-based fusion peptide in the transfected H1299 lung cancer cells
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作者 王宏涛 《外科研究与新技术》 2011年第3期157-157,共1页
Objective Loss-of-function mutation of p53,a tumor suppressor gene,is an important mechanism for the development of human cancers. In this study we tried to transfect p53N15-based fusion peptide into H1299,a lung canc... Objective Loss-of-function mutation of p53,a tumor suppressor gene,is an important mechanism for the development of human cancers. In this study we tried to transfect p53N15-based fusion peptide into H1299,a lung cancer cell line,and evaluate the anti-tumor effects of the fusion peptide. Methods Adeno-associated virus (AAV) vectors were used for transfecting p53N15 fusion peptide into p53-null lung adenocarcinoma H1299 cells. 展开更多
关键词 LUNG anti-tumor effects of p53N15-based fusion peptide in the transfected H1299 lung cancer cells
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Anti-tumor Effects of a Recombinant Fowlpox Virus Expressing Apoptin on Human Cervical Carcinoma in Vivo and in Vitro 被引量:3
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作者 ZHU Ji-hong LI Xiao +7 位作者 SUN Li-li ZHANG Mu-chun KAN Shi-fu LIU Lei HUANG Hai-yan YANG Guo-hua PIAO Bing-guo JIN Ning-yi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第4期646-650,共5页
Apoptin is a chicken anemia virus-derived,p53-independent,bcl-2-insensitive apoptotic protein with the ability to specifically induce apoptosis of various human tumor cells,but not of normal diploid cells.To explore t... Apoptin is a chicken anemia virus-derived,p53-independent,bcl-2-insensitive apoptotic protein with the ability to specifically induce apoptosis of various human tumor cells,but not of normal diploid cells.To explore the application of apoptin in tumor gene therapy,we used a recombinant fowlpox virus expressing apoptin protein (vFV-Apoptin) to investigate the anti-tumor effectes of vFV-Apoptin on human cervical carcinoma(HeLa) cells in vivo and in vitro through 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide(MTT) assay,acridine orage/ethidium bromide(AO/EB) and annexin V staining test,respectively.The results show that vFV-Apoptin inhibites the proliferation of HeLa cells in vitro through inducing the apoptosis of HeLa cells,and the inhibition effect of vFV-Apoptin has a dose-effect and time-effect relationship.The results of animal models show that vFV-Apoptin significantly inhibits tumor growth,extends the lifespan of animals and improves the mean survival.Experimental results indicate that vFV-Apoptin has a potential application in the tumor gene therapy. 展开更多
关键词 Apoptin gene Chicken anemia virus Human cervical carcinoma anti-tumor effect
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Anti-tumor Effects of Aspirin: Progress in Clinical and Basic Studies 被引量:1
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作者 Hui Liu Yan Chen Qiang +2 位作者 Yong Qiang Xiong Hao Chen He Huang 《Journal of Nutritional Oncology》 2020年第2期71-77,共7页
Beyond the antipyretic analgesic and anti-inflammatory effects for which aspirin has historically been used,studies have shown that aspirin also plays an important role in the prevention or treatment a variety of dise... Beyond the antipyretic analgesic and anti-inflammatory effects for which aspirin has historically been used,studies have shown that aspirin also plays an important role in the prevention or treatment a variety of diseases.The anti-tumor effects of aspirin have received increasing attention during the past decade.Many studies have explored the molecular mechanisms underlying these anti-tumor effects in vitro and in vivo,and abundant discoveries have been made through observational or interventional clinical studies.In terms of its molecular function,aspirin has been shown to prevent tumor cell growth through inhibiting the signal transduction of the COX,tumor necrosis factor-related apoptosis-inducing ligand(TRAIL),NFκB/IκB,and Bcl-2/Bax pathways.Under certain conditions,aspirin can also induce autophagy,which is an inhibitory mechanism for some tumors.This article provides a comprehensive overview of the anti-tumor effects of aspirin and discusses the concrete mechanisms underlying aspirin’s anti-tumor effects that have been discovered in the past 30 years. 展开更多
关键词 ASPIRIN anti-tumor Clinical research Molecular mechanism Non-steroidal anti-inflammatory drugs
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Research Progress of Anti-tumor Effects of Curcuma zedoaria and its Active Ingredients Through Immune Regulation Mechanism
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作者 Zhuli Hou Gang Fang 《Journal of Clinical and Nursing Research》 2021年第4期1-7,共7页
The continuous increase in the incidence rate of various fatal malignant tumors in the recent years warrants an imperative search for medications or drugs with obvious anti-tumor eflects and reliable curative effects.... The continuous increase in the incidence rate of various fatal malignant tumors in the recent years warrants an imperative search for medications or drugs with obvious anti-tumor eflects and reliable curative effects.Previous studies have found that Curcuma zedoaria and its active ingredients,such as turmeric oil,curcumol,and P-elemene,have obvious antitumor effects,and they do not have the adverse reactions and side effects seen in the anti-tumor drugs of Western medicine.Based on the review and inductive analysis of related literature,we summarize in the present article the results of some researchers who investigated the anti-tumor effects of Curcuma zedoaria and its active ingredients through the immune regulation mechanism. 展开更多
关键词 Malignant tumor Curcuma zedoaria and its active ingredients Immune regulation MECHANISM anti-tumor effect
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Anti-Tumor and Anti-Diabetic Effects of Sarsasapogenin
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作者 Mingxinzhi WANG Jingchao WANG +3 位作者 Quan QUAN Xichun HUANG Xinyu LIU Chenghao JIN 《Medicinal Plant》 2024年第1期59-61,共3页
In this paper,the pharmacological effects and molecular mechanisms of sarsasapogenin,such as anti-oxidant,anti-inflammatory and anti-diabetic effects,are reviewed in order to provide a theoretical basis for the subseq... In this paper,the pharmacological effects and molecular mechanisms of sarsasapogenin,such as anti-oxidant,anti-inflammatory and anti-diabetic effects,are reviewed in order to provide a theoretical basis for the subsequent development and clinical application of sarsasapogenin. 展开更多
关键词 SARSASAPOGENIN anti-tumor ANTI-DIABETIC ANTI-INFLAMMATORY
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Mechanism of Anti-tumor Effects of Viola Medicinal Materials Based on Network Pharmacology and Molecular Docking
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作者 Xiaoyong HE Liniu SHAMA +4 位作者 Dongmei SHA Shuaicong NI Jing WEN Xinjia YAN Yuan LIU 《Medicinal Plant》 2024年第3期9-15,共7页
[Objectives]To explore the relationship between anti-tumor components,targets,and pathways involved in Viola medicinal materials,study its main active components,and evaluate its inhibitory activity.[Methods]Through n... [Objectives]To explore the relationship between anti-tumor components,targets,and pathways involved in Viola medicinal materials,study its main active components,and evaluate its inhibitory activity.[Methods]Through network pharmacological analysis,molecular docking simulation experiments and in vitro experiments,the main components and corresponding targets of Viola were screened out,and their anti-tumor signaling pathways were confirmed.MTT colorimetric assay was used to investigate the inhibitory effect of different extraction layers of Viola on the growth of tumor cells.[Results]18 anti-tumor active components such as 2α,19α-Dihydroxyursolic acid,Corlumine,Madolin U,Trifolirhizin and etc.,and 52 action targets such as PTGS2,PTGS1,P2RX7,MMP1,and GABRB3,and anti-tumor signaling pathways were confirmed.The results of molecular docking showed that all the selected Viola compounds had good binding activity.The results of MTT colorimetric assay showed that the petroleum ether layer and n-butanol layer had a good inhibitory effect on the growth of tumor cell lines.[Conclusions]Viola medicinal materials have the potential of anti-tumor,triterpenoids and flavonoids may be the main active components,and the petroleum ether layer and n-butanol layer have better inhibitory effect on the growth of tumor cells. 展开更多
关键词 Viola medicinal materials anti-tumor Network pharmacology Molecular docking MTT
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Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020 被引量:1
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作者 ZHU Yuanyuan ZHANG Yan ZHU Xiaohua 《Chinese Geographical Science》 SCIE CSCD 2024年第1期181-194,共14页
Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research ob... Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern. 展开更多
关键词 dietary structure structural evolution carbon emission effects carbon neutrality China
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Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement
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作者 Yuanyuan Wang Xinzhu Dai +5 位作者 Xingling Chen Dan Zhang Guiqing Lin Yuanhang Zhou Tianyi Wang Yulong Cui 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期146-162,共17页
Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban... Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future. 展开更多
关键词 Species diversity Forest characteristics Biomass carbon sink Forest-type effect Urbanization effect Urban forests
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Advances in Research of Anti-tumor Effect of Aconiti Radix
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作者 Jing GAO Fanbo JING +2 位作者 Lifang FENG Wen XU Changkai ZHOU 《Medicinal Plant》 2024年第2期80-83,共4页
In this paper,the anti-tumor effects of Aconiti Radix were reviewed and summarized,and the clinical feasibility of Aconiti Radix as a potential anti-tumor drug was analyzed,in order to provide a useful reference for t... In this paper,the anti-tumor effects of Aconiti Radix were reviewed and summarized,and the clinical feasibility of Aconiti Radix as a potential anti-tumor drug was analyzed,in order to provide a useful reference for the future research and development of new anti-cancer drugs of Aconiti Radix. 展开更多
关键词 Aconiti Radix anti-tumor Research advances Feasibility analysis
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Effects of Maternal Death on Children Living in the Sagnarigu Municipality
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作者 David Z. Kolbila Abdul-Razak Doat +2 位作者 David S. Nigarim Wilfred Kwose Sylvanus Kampo 《Open Journal of Obstetrics and Gynecology》 2024年第3期334-347,共14页
Introduction: The greatest effect of maternal mortality is renowned in children aged 2 - 5 months whose mothers had died. Children whose mothers died due to maternal complications were likely to record a higher mortal... Introduction: The greatest effect of maternal mortality is renowned in children aged 2 - 5 months whose mothers had died. Children whose mothers died due to maternal complications were likely to record a higher mortality in infancy compared to children of surviving mothers. Motherless children mostly suffer a lot due to lack of day-to-day care, isolation, lack of motivation as well as economic cost associated with mother’s death. Thus, the purpose of this study was to ascertain the lives of children whose mothers passed away during childbirth at the Sagnarigu Municipality. Methods: This quantitative cross-sectional study was carried out at the Sagnarigu Municipal. The study recruited 297 respondents. To assess the effects of maternal death on the lives of children, families that experienced maternal death were assessed. The number of pregnancies experienced by the deceased woman, pregnancy-related complaints experienced, determinants of maternal death, number of children alive, and their standard of living were assessed with the aid of a structured questionnaire. Results: The data showed that negligence, illiteracy, poor road access, poverty, ignorance, delays in recognizing the problem, delays in making appropriate decisions, delays in the health facility, delays in giving the appropriate treatments, and traditional beliefs were some of the factors that led to maternal death in the Sagnarigu Municipality. Conclusion: The study concluded that determinants of maternal death in the Sagnarigu Municipal included the following;negligence, illiteracy, poverty, and delays in recognizing the problem. The study findings also demonstrated that the effects of maternal death on children are diverse and cut across different areas of a child’s life including livelihood sustenance, healthcare, education, and emotional and psychological development. 展开更多
关键词 Maternal Death effects Orphans CHILDREN PREGNANCY CHILDBIRTH
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Review of Sc microalloying effects in Al-Cu alloys
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作者 Shenghua Wu Chong Yang +7 位作者 Peng Zhang Hang Xue Yihan Gao Yuqing Wang Ruihong Wang Jinyu Zhang Gang Liu Jun Sun 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1098-1114,共17页
Artificially controlling the solid-state precipitation in aluminum (Al) alloys is an efficient way to achieve well-performed properties,and the microalloying strategy is the most frequently adopted method for such a p... Artificially controlling the solid-state precipitation in aluminum (Al) alloys is an efficient way to achieve well-performed properties,and the microalloying strategy is the most frequently adopted method for such a purpose.In this paper,recent advances in lengthscale-dependent scandium (Sc) microalloying effects in Al-Cu model alloys are reviewed.In coarse-grained Al-Cu alloys,the Sc-aided Cu/Sc/vacancies complexes that act as heterogeneous nuclei and Sc segregation at the θ′-Al_(2)Cu/matrix interface that reduces interfacial energy contribute significantly to θ′precipitation.By grain size refinement to the fine/ultrafine-grained scale,the strongly bonded Cu/Sc/vacancies complexes inhibit Cu and vacancy diffusing toward grain boundaries,promoting the desired intragranular θ′precipitation.At nanocrystalline scale,the applied high strain producing high-density vacancies results in the formation of a large quantity of (Cu Sc,vacancy)-rich atomic complexes with high thermal stability,outstandingly improving the strength/ductility synergy and preventing the intractable low-temperature precipitation.This review recommends the use of microalloying technology to modify the precipitation behaviors toward better combined mechanical properties and thermal stability in Al alloys. 展开更多
关键词 aluminum alloy microalloying effect length-scale dependence PRECIPITATION mechanical properties
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Temporal changes in mixing effects on litter decay and nitrogen release in a boreal riparian forest in northeastern China
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作者 Simin Wang Bo Liu +2 位作者 Rui Li Xiaoxin Sun Rong Mao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期33-41,共9页
In riparian forests,litter decay provides essential energy and nutrients for both terrestrial and fluvial ecosystems.Litter mixing effects(LMEs)are crucial in regulating litter decay and nutrient dynamics,yet how LMEs... In riparian forests,litter decay provides essential energy and nutrients for both terrestrial and fluvial ecosystems.Litter mixing effects(LMEs)are crucial in regulating litter decay and nutrient dynamics,yet how LMEs change over time is unclear in riparian forests.In this study,leaf litter of three common species(Alnus sibirica Fisch.ex Turcz,Betula platyphylla Sukaczev,and Betula fruticosa Pall.)were mixed in an equal mass ratio and LMEs were measured for mass and nitrogen(N)remaining in whole litter mixtures over a 3-year period in a boreal riparian forest,northeastern China.LMEs were also assessed for component litter mass and N remaining by separating litter mixtures by species.During the decay of litter mixtures,antagonistic effects on mass and N remaining were dominant after one and two years of decay,whereas only additive effects were observed after three years.LMEs correlated negatively with functional diversity after the first and two years of decay but disappeared after three years.When sorting litter mixtures by species,non-additive LMEs on mass and N remaining decreased over incubation time.Moreover,non-additive LMEs were more frequent for litter of both B.platyphylla and B.fruticosa with lower N concentration than for A.sibirica litter with higher N concentration.These results indicate that incubation time is a key determinant of litter mixing effects during decay and highlight that late-stage litter mixture decay may be predicted from single litter decay dynamics in boreal riparian forests. 展开更多
关键词 BIODIVERSITY Litter quality Litter mixtures Synergistic effects Functional diversity
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Electronic effects on radiation damage inα-iron:A molecular dynamics study
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作者 江林 李敏 +2 位作者 付宝勤 崔节超 侯氢 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期521-529,共9页
Iron(Fe)-based alloys,which have been widely used as structural materials in nuclear reactors,can significantly change their microstructure properties and macroscopic properties under high flux neutron irradiation dur... Iron(Fe)-based alloys,which have been widely used as structural materials in nuclear reactors,can significantly change their microstructure properties and macroscopic properties under high flux neutron irradiation during operation,thus,the problems associated with the safe operation of nuclear reactors have been put forward naturally.In this work,a molecular dynamics simulation approach combined with electronic effects is developed for investigating the primary radiation damage process inα-Fe.Specifically,the influence of electronic effects on the collision cascade in Fe is systematically evaluated based on two commonly used interatomic potentials for Fe.The simulation results reveal that both electronic stopping(ES)and electron-phonon coupling(EPC)can contribute to the decrease of the number of defects in the thermal spike phase.The application of ES reduces the number of residual defects after the cascade evolution,whereas EPC has a reverse effect.The introduction of electronic effects promotes the formation of the dispersive subcascade:ES significantly changes the geometry of the damaged region in the thermal spike phase,whereas EPC mainly reduces the extent of the damaged region.Furthermore,the incorporation of electronic effects effectively mitigates discrepancies in simulation outcomes when using different interatomic potentials. 展开更多
关键词 radiation damage electronic effects molecular dynamics simulation α-iron
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Solvent effects on Diels-Alder reaction in ionic liquids:A reaction density functional study
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作者 Zijiang Dou Weiqiang Tang +1 位作者 Peng Xie Shuangliang Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期180-188,共9页
Extensive experimental studies have been performed on the Diels-Alder(DA)reactions in ionic liquids(ILs),which demonstrate that the IL environment can significantly influence the reaction rates and selectivity.However... Extensive experimental studies have been performed on the Diels-Alder(DA)reactions in ionic liquids(ILs),which demonstrate that the IL environment can significantly influence the reaction rates and selectivity.However,the underlying microscopic mechanism remains ambiguous.In this work,the multiscale reaction density functional theory is applied to explore the effect of 1-butyl-3-methylimidazolium hexafluorophosphate([BMIM][PF_(6)])solvent on the reaction of cyclopentadiene(CP)with acrolein,methyl acrylate,or acrylonitrile.By analyzing the free energy landscape during the reaction,it is found that the polarization effect has a relatively small influence,while the solvation effect makes both the activation free energy and reaction free energy decrease.In addition,the rearrangement of local solvent structure shows that the cation spatial distribution responds more evidently to the reaction than the anion,and this indicates that the cation plays a dominant role in the solvation effect and so as to affect the reaction rates and selectivity of the DA reactions. 展开更多
关键词 Solvent effect Ionic liquids Diels-Alder reaction Reaction density functional theory
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Nuclear volume effects in kinetic isotope fractionation:A case study of mercury oxidation by chlorine species
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作者 Chenlu Yang Yining Zhang Yun Liu 《Acta Geochimica》 EI CAS CSCD 2024年第3期411-423,共13页
It is well-known that the equilibrium isotope fractionation of mercury(Hg)includes classical massdependent fractionations(MDFs)and nuclear volume effect(NVE)induced mass-independent fractionations(MIFs).However,the ef... It is well-known that the equilibrium isotope fractionation of mercury(Hg)includes classical massdependent fractionations(MDFs)and nuclear volume effect(NVE)induced mass-independent fractionations(MIFs).However,the effect of the NVE on these kinetic processes is not known.The total fractionations(MDFs+NVEinduced MIFs)of several representative Hg-incorporated substances were selected and calculated with ab initio calculations in this work for both equilibrium and kinetic processes.NVE-induced MIFs were calculated with scaled contact electron densities at the nucleus through systematic evaluations of their accuracy and errors using the Gaussian09 and DIRAC19 packages(named the electron density scaling method).Additionally,the NVE-induced kinetic isotope effect(KIE)of Hg isotopes are also calculated with this method for several representative Hg oxidation reactions by chlorine species.Total KIEs for 202 Hg/^(198)Hg ranging from−2.27‰to 0.96‰are obtained.Three anomalous^(202)Hg-enriched KIEs(δ^(202)Hg/^(198)Hg=0.83‰,0.94‰,and 0.96‰,)caused by the NVE are observed,which are quite different from the classical view(i.e.,light isotopes react faster than the heavy ones).The electron density scaling method we developed in this study can provide an easier way to calculate the NVE-induced KIEs for heavy isotopes and serve to better understand the fractionation mechanisms of mercury isotope systems. 展开更多
关键词 Nuclear volume effect Kinetic fractionation Hg isotopes Ab initio calculations
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GPCR-Gs mediates the protective effects of ginsenoside Rb1 against oxygen-glucose deprivation/re-oxygenation-induced astrocyte injury
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作者 Xi Wang Ying Liu +3 位作者 Juan Li Jiayu Xie Yi Dai Minke Tang 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期33-43,共11页
Objectives:To investigate whether the protective actions of ginsenoside Rb1(Rb1)on astrocytes are mediated through the G_(s)-type G-protein-coupled receptor(GPCR-G_(s)).Methods:Primary astrocyte cultures derived from ... Objectives:To investigate whether the protective actions of ginsenoside Rb1(Rb1)on astrocytes are mediated through the G_(s)-type G-protein-coupled receptor(GPCR-G_(s)).Methods:Primary astrocyte cultures derived from neonatal mouse brain were used.Astrocyte injury was induced via oxygen-glucose deprivation/re-oxygenation(OGD/R).Cell morphology,viability,lactate dehydrogenase(LDH)leakage,apoptosis,glutamate uptake,and brain-derived neurotrophic factor(BDNF)secretion were assessed to gauge cell survival and functionality.Western blot was used to investigate the cyclic adenosine monophosphate(cAMP)and protein kinase B(Akt)signaling pathways.GPCR-G_(s)-specific inhibitors and molecular docking were used to identify target receptors.Results:Rb1 at concentrations ranging from 0.8 to 5μM did not significantly affect the viability,glutamate uptake,or BDNF secretion in normal astrocytes.OGD/R reduced astrocyte viability,increasing their LDH leakage and apoptosis rate.It also decreased glutamate uptake and BDNF secretion by these cells.Rb1 had protective effects of astrocytes challenged by OGD/R,by improving viability,reducing apoptosis,and enhancing glutamate uptake and BDNF secretion.Additionally,Rb1 activated the cAMP and Akt pathways in these cells.When the GPCR-G_(s) inhibitor NF449 was introduced,the protective effects of Rb1 completely disappeared,and its activation of cAMP and Akt signaling pathways was significantly inhibited.Conclusion:Rb1 protects against astrocytes from OGD/R-induced injury through GPCR-G_(s) mediation. 展开更多
关键词 GINSENG Ginsenoside Rb1 Receptor GPCR ASTROCYTES Neuroprotective effects
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Decoupling of temporal/spatial broadening effects in Doppler wind LiDAR by 2D spectral analysis
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作者 刘珍 张云鹏 +3 位作者 竹孝鹏 刘继桥 毕德仓 陈卫标 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期447-452,共6页
Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and freque... Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and frequency dimension to cope with the temporal wind shear and achieve the optimal accumulation time.A hardware-efficient algorithm combining the interpolation and cross-correlation is used to enhance the wind retrieval accuracy by reducing the frequency sampling interval and then reduce the spectral width calculation error.Moreover,the temporal broadening effect and spatial broadening effect are decoupled according to the strategy we developed. 展开更多
关键词 Doppler wind LiDAR spectral analysis hardware efficiency spectrum broadening effects
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