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Functional macrocyclic arenes with active binding sites inside cavity for biomimetic molecular recognition
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作者 Xixian Sun Shengke Li +1 位作者 Ruibing Wang Leyong Wang 《Chinese Chemical Letters》 2025年第4期1-2,共2页
Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active... Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active sites inside the cavity of macrocyclic arenes to better mimic molecular recognition of bioreceptors and enzymes.The editorial aims to enlighten scientists in this field when they develop novel macrocycles for molecular recognition, supramolecular assembly, and applications. 展开更多
关键词 supramolecular assembly orthogonal interactions introducing active sites active binding sites macrocyclic arenes molecular recognition orthogonal interactions small molecules biomimetic molecular recognition
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Security distance analysis of active distribution network considering energy hub demand response
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作者 Rui Ma Qi Zhou +2 位作者 Shengyang Liu Qin Yan Mo Shi 《Global Energy Interconnection》 2025年第1期160-173,共14页
This study proposes a method for analyzing the security distance of an Active Distribution Network(ADN)by incorporating the demand response of an Energy Hub(EH).Taking into account the impact of stochastic wind-solar ... This study proposes a method for analyzing the security distance of an Active Distribution Network(ADN)by incorporating the demand response of an Energy Hub(EH).Taking into account the impact of stochastic wind-solar power and flexible loads on the EH,an interactive power model was developed to represent the EH’s operation under these influences.Additionally,an ADN security distance model,integrating an EH with flexible loads,was constructed to evaluate the effect of flexible load variations on the ADN’s security distance.By considering scenarios such as air conditioning(AC)load reduction and base station(BS)load transfer,the security distances of phases A,B,and C increased by 17.1%,17.2%,and 17.7%,respectively.Furthermore,a multi-objective optimal power flow model was formulated and solved using the Forward-Backward Power Flow Algorithm,the NSGA-II multi-objective optimization algo-rithm,and the maximum satisfaction method.The simulation results of the IEEE33 node system example demonstrate that after opti-mization,the total energy cost for one day is reduced by 0.026%,and the total security distance limit of the ADN’s three phases is improved by 0.1 MVA.This method effectively enhances the security distance,facilitates BS load transfer and AC load reduction,and contributes to the energy-saving,economical,and safe operation of the power system. 展开更多
关键词 active distribution network Energy hub Security distance Base station load Air-conditioning load
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Analyzing the Resilience of Active Distribution Networks to Hazardous Weather Considering Cyber-Physical Interdependencies
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作者 Zhiyi Li Xutao Han +2 位作者 Mohammad Shahidehpour Ping Ju Qun Yu 《Engineering》 2025年第8期15-36,共22页
This paper provides a systematic review on the resilience analysis of active distribution networks(ADNs)against hazardous weather events,considering the underlying cyber-physical interdependencies.As cyber-physical sy... This paper provides a systematic review on the resilience analysis of active distribution networks(ADNs)against hazardous weather events,considering the underlying cyber-physical interdependencies.As cyber-physical systems,ADNs are characterized by widespread structural and functional interdependen-cies between cyber(communication,computing,and control)and physical(electric power)subsystems and thus present complex hazardous-weather-related resilience issues.To bridge current research gaps,this paper first classifies diverse hazardous weather events for ADNs according to different time spans and degrees of hazard,with model-based and data-driven methods being utilized to characterize weather evolutions.Then,the adverse impacts of hazardous weather on all aspects of ADNs’sources,physical/cyber networks,and loads are analyzed.This paper further emphasizes the importance of situational awareness and cyber-physical collaboration throughout hazardous weather events,as these enhance the implementation of preventive dispatches,corrective actions,and coordinated restorations.In addition,a generalized quantitative resilience evaluation process is proposed regarding additional considerations about cyber subsystems and cyber-physical connections.Finally,potential hazardous-weather-related resilience challenges for both physical and cyber subsystems are discussed. 展开更多
关键词 Cyber–physical interdependency Resilience analysis active distribution network Hazardous weather event
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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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Comparative Risk of Stroke Associated with Active Smoking in Chinese and Asian Populations
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作者 Zemin Cai Xiaojing Guo +3 位作者 Xiao Zhang Danying Li Xiaoyue Li Xia Wan 《Biomedical and Environmental Sciences》 2026年第1期60-72,共13页
Objective Stroke is the third leading cause of death worldwide,with the highest incidence in Asia,particularly in China,where smoking remains a major risk factor.The smoking prevalence in China is similar to that in A... Objective Stroke is the third leading cause of death worldwide,with the highest incidence in Asia,particularly in China,where smoking remains a major risk factor.The smoking prevalence in China is similar to that in Asia.Whether the risk estimates for smoking-related stroke in China and all Asian countries are still unknown which is worth evaluating.Thus,this study aims to compare the Relative Risk(RR)of smoking-attributed stroke among the Chinese and Asian populations.Methods A literature search was conducted from the inception to September 10,2022.Studies meeting the criteria were included.The articles were screened,and related information was extracted.Pooled RRs stratified by smoking status and sex were analyzed,including subgroup analyses for China,other Asian countries,and Asia overall.Finally,publication bias and sensitivity analyses were conducted.Results Thirty-seven articles on the Chinese population and 15 on other Asian populations were included,with a mean Newcastle-Ottawa scale(NOS)score of 7.25.About ever smokers,there had no statistical difference existed in both sexes and females between China and other Asian countries,while the RR of males in other Asian countries[2.31(1.38,3.86)]was higher than that in China[1.21(1.15,1.26)];further subgroup analysis indicated that other Asian countries had higher RR[3.76(3.02,4.67)]in the morbidity subgroup.The RRs of both sexes,males and females,between China and the whole of Asia were not statistically different.As for current and former smokers,no meaningful statistical difference was observed in the pooled RRs of both sexes,males and females,in China,other Asian countries,and all of Asia.Conclusion The RR of males ever smokers in China was smaller than that in other Asian countries due to the few articles of morbidity subgroup,but had no statistical difference with the whole of Asia;other groups of ever smokers,current smokers,and former smokers were not statistically significant with other Asian countries or the whole of Asia. 展开更多
关键词 active smoking STROKE China Asian countries META-ANALYSIS
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A review of the pharmacology of active ingredients in Ginseng Radix et Rhizoma(Renshen)anti-aging
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作者 Tian-Yuan Liu Jin-Ning Chang +6 位作者 Xiao-Wei Dai Hao-Xin Ma Wei-Jia Chen Rui Du Akmal Muhammad Jian-Ming Li Zhong-Mei He 《Traditional Medicine Research》 2026年第3期65-76,共12页
Population aging is one of the common challenges in the current world.As people age,the body’s tissues including cells,and molecules inevitably degrade,and their functions gradually decline,causing various age-relate... Population aging is one of the common challenges in the current world.As people age,the body’s tissues including cells,and molecules inevitably degrade,and their functions gradually decline,causing various age-related diseases like Alzheimer’s disease,osteoporosis,low immunity,glucose and lipid metabolism disorders,and cardiovascular diseases.With the continuous increase of the elderly population,the pressure on the medical industry is increasing.To lower the burden on the medical industry and increase the average age of the elderly,it is vital to explore effective anti-aging materials.Ginseng Radix et Rhizoma(Renshen),as a traditional and precious Chinese medicinal herb,is known as the“king of all herbs”.It is famous for its effects of“tonifying Qi,restoring pulse”(helping with the generation of Qi(the fundamental,vital energy that continuously flows within the body)and the circulation of blood)and strengthening the body,nourishing the spleen and lungs,generating fluids and nourishing blood,calming the mind and improving intelligence.Recently,its anti-aging effect has received increasing attention from modern scientific research.This study summarizes the pharmacological effects of the main active ingredients of Renshen(ginsenosides,polysaccharides,etc.)on resisting aging,including preventing neuroaging,suppressing skin aging,mitigating ovarian aging,inhibiting osteoporosis and arthritis,enhancing the immune system of the elderly,protecting the cardiovascular system,resisting aging-induced fatigue and exerting the anti-tumor effects.Through network pharmacology and molecular docking,the anti-aging active ingredients of Renshen were screened,and the key targets and pathways of anti-aging active ingredients in Renshen were determined.Using network pharmacology,totally 106 drug targets and 3,479 disease targets were screened,and 79 common targets between aging and Renshen were identified.Three core targets were identified in the PPI network,including TNF,AKT1,and IL-1β.Molecular docking was used to obtain further verification.This study emphasizes the potential of Renshen as a source of anti-aging activity,which can be developed into a novel drug for the treatment of age-related diseases. 展开更多
关键词 Renshen active ingredients ANTI-AGING pharmacological effects network pharmacology molecular docking
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Stratospheric transport and residence time of Hunga volcanic aerosol
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作者 Qing Zhao Xin Zhou 《Earth and Planetary Physics》 2026年第1期167-175,共9页
The January 2022 eruption of Hunga injected unprecedented volumes of water vapor(150 Tg)and modest sulfur dioxide(SO_(2))into the stratosphere,producing accelerated sulfate aerosol formation in the early plume.As the ... The January 2022 eruption of Hunga injected unprecedented volumes of water vapor(150 Tg)and modest sulfur dioxide(SO_(2))into the stratosphere,producing accelerated sulfate aerosol formation in the early plume.As the aerosols gradually spread into the global stratosphere,the role of water vapor,among other factors in the spread and residence time of the sulfate aerosols,remained unclear.We used multisatellite observations to better understand the role of water vapor in the spread and lifetime of Hunga volcanic aerosols.Stratospheric circulation transported the plumes to~26 km within the polar vortices-the Antarctic by August 2022 and the Arctic by January 2023-with the arrival of aerosols lagging behind that of water vapor by months.Even though high injection altitudes(58 km)and strong Brewer-Dobson circulation contributed to prolonging the residence time of aerosols,the water vapor enhanced particle growth and thus accelerated gravitational settling,with the half lifetime of aerosols being 14 months.Our analysis revealed a critical trade-off:after the eruption of the Hunga volcano,an extremely high injection height and strong upward motion slowed the removal of aerosols,but extreme water vapor loading still had a certain impact on the half lifetime of the aerosols.These findings highlight the role of water vapor in the persistence of aerosols from submarine eruptions. 展开更多
关键词 STRATOSPHERE water vapor aerosol lifetime volcanic activity
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A new flavonol C-glycoside and a rare bioactive lignanamide from Piper wallichii Miq. Hand.-Mazz 被引量:5
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作者 WANG Pei-Pei ZHAO Guo-Wei +2 位作者 XIA Wen HAN En-Ji XIANG Lan 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2014年第5期377-381,共5页
This study was conducted to investigate the chemical constituents of Piper wallichii (Miq.) Hand.-Mazz. and evaluate their biological activity. Compounds were isolated by various column chromatographic methods, and ... This study was conducted to investigate the chemical constituents of Piper wallichii (Miq.) Hand.-Mazz. and evaluate their biological activity. Compounds were isolated by various column chromatographic methods, and their structures were elucidated on the basis of physical characteristics and spectral data. The 1, 1-diphenyl-2-picrylhydrazyl (DPPH)-scavenging activity and acetylcholinesterase (AChE)-inhibitory activity of the compounds were evaluated. Five compounds were obtained and identified as 8-C-β-D-glucopyranosylkaempferol-3-O-β-D-glucopyranoside (1), 1, 2-dihydro-6,8-dimethoxy-7-hydroxy-l-(3, 5-dimethoxy-4-hydroxyphenyl)-N^1, N^2-bis-[2-(4-hydroxyphenyl)ethyl]-2, 3-naphthalene dicarboxamide (2), goniothalactam (3), aristololactam A IIla (4) and piperlonguminine (5). Compound 1 was a new flavonol C-glycoside, 2 was a rare lignanamide, which was isolated from the family Piperaceae for the first time, and compound 3 was isolated from this plant for the first time. Among them, 2 showed potent DPPH-scavenging activity, with IC50 of 31.38 ± 0.97 μmol·L^-1; Compounds 2, 3, and 4 showed AChE inhibitory activity at 100 μmol·L^-1, with inhibition rates of 28.57% ± 1.47%, 18.48% ± 2.41% and 17.4% ±3.03%, respectively. 展开更多
关键词 Piper wallichii Flavonol C-glycoside Lignanamide DPPH scavenging activity AChE inhibitory activity
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Three new bioactive flavonoid glycosides from Viscum album 被引量:3
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作者 DAI Jia-Kun CAO Duo +6 位作者 LI Cui-Hua GAO Jing LI Meng-Qing FAN Na WEI Ya-Hui SUN Zheng-Liang HOU Meng-Yang 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2019年第7期545-550,共6页
Two new flavonoid glycosides, named viscumneoside XⅡ(1), and viscumneoside XⅢ(2);a new dihydrogen flavonoid glycoside product named viscumneoside XⅣ(3), were isolated from the aerial part of Viscum album, along wit... Two new flavonoid glycosides, named viscumneoside XⅡ(1), and viscumneoside XⅢ(2);a new dihydrogen flavonoid glycoside product named viscumneoside XⅣ(3), were isolated from the aerial part of Viscum album, along with seven known compounds(4-10). Their structures were identified by analysis of spectroscopic data. In addition, cytotoxicity assay showed that 1, 2 and 3 possessed significant inhibitory activities against C6, A549 and MDA-MB-231(the inhibition rate arrived about 50%, 70% and74% respectively with IC50 ≤ 60.00 μmol·L^-1), while the inhibition of TF-1 and Hela was not significant. 展开更多
关键词 Viscum ALBUM Flavonoid GLYCOsideS CYTOTOXIC ACTIVITIES
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Improved method for determining active earth pressure considering arching effect and actual slip surface 被引量:3
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作者 HE Zhong-ming LIU Zheng-fu +1 位作者 LIU Xiao-hong BIAN Han-bing 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第7期2032-2042,共11页
To determine the distribution of active earth pressure on retaining walls, a series of model tests with the horizontally translating rigid walls are designed. Particle image velocimetry is used to study the movement a... To determine the distribution of active earth pressure on retaining walls, a series of model tests with the horizontally translating rigid walls are designed. Particle image velocimetry is used to study the movement and shear strain during the active failure of soil with height H and friction angle φ. The test results show that there are 3 stages of soil deformation under retaining wall translation: the initial stage, the expansion stage and the stability stage. The stable sliding surface in the model tests can be considered to be composed of two parts. Within the height range of 0.82 H-1.0 H, it is a plane at an angle of π/4+φ/2 to the horizontal plane. In the height range of 0-0.82 H, it is a curve between a logarithmic spiral and a plane at an angle of π/4+φ/2 to the horizontal. A new method applicable to any sliding surface is proposed for active earth pressure with the consideration of arching effect. The active earth pressure is computed with the actual shape of the slip surface and compared with model test data and with predictions obtained by existing methods. The comparison shows that predictions from the newly proposed method are more consistent with the measured data than the predictions from the other methods. 展开更多
关键词 particle image velocimetry retaining wall soil arching effect active earth pressure
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General variational solution for seismic and static active earth pressure on rigid walls considering soil tensile strength cut-off 被引量:1
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作者 Shiguo XIAO Yuan QI Pan XIA 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2023年第5期432-449,共18页
According to the limit equilibrium state of soils behind rigid walls and the pseudo-static approach,a general closed-form solution to seismic and static active earth pressure on the walls,which considers shear and ten... According to the limit equilibrium state of soils behind rigid walls and the pseudo-static approach,a general closed-form solution to seismic and static active earth pressure on the walls,which considers shear and tension failure of the retained soil,is put forward using a variational calculus method.The application point of the active resultant force specified in the proposed method is explained with a clear physical meaning related to possible movement modes of the walls.In respect of the derived nine dependent equations reflecting the functional characteristics of the earth pressure,the proposed method can be performed easily via an implicit strategy.There are 13 basic factors related to the retained soils,walls,and external loads to be involved in the proposed method.The tension crack segment of the slip surface is obviously influenced by these parameters,apart from vertical seismic coefficient and geometric bounds of the surcharge,but the shear slip segment maintains an approximately planar shape almost uninfluenced by these parameters.Noticeably,the proposed method quantitatively reflects that the resultant of the active earth pressure is always within a limited range under different possible movements of the same wall. 展开更多
关键词 active earth pressure Tensile strength cut-off Variational calculus method Pseudo-static method Strip surcharge
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Chemical Vapor Deposition of β-SiC Nanowires on Granular Active Carbon Cylinders Loaded with Iron Nanoparticles Inside the Pores 被引量:1
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作者 MENG Guo-wen ZHANG Li-de +4 位作者 QIN Yong FPhillipp QIAO Sheng-ru GUO Hai-ming ZHANG Shu-yuan 《Chinese Physics Letters》 SCIE CAS CSCD 1998年第9期689-691,共3页
A new method for chemical vapor deposition ofβ-SiC nanowires on granular active carbon loaded with iron nanoparticles inside the pores is developed.In this process,mesoporous active carbon was used as both a carbon s... A new method for chemical vapor deposition ofβ-SiC nanowires on granular active carbon loaded with iron nanoparticles inside the pores is developed.In this process,mesoporous active carbon was used as both a carbon source material and a template to generate nanometer-diameter catalyst particles that define the size of wires produced by vapor-liquid-solid(VLS)growth.Transmission electron microscopy reveals that the products are nanowires with several microns in length and about 10nm in diameter.Selected area electron-diffraction and energy-dispersed x-ray spectra confirm that the productor isβ-SiC.The observation of spherical nanoparticles containing iron at the end of the nanowires clearly indicates that the nanowires grow by the VLS mechanism. 展开更多
关键词 NANOWIRES active TEMPLATE
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A Quantitative Method for Active Fault Migration Distance Assessment on both Sides of Mid-Ocean Ridges——Based on Multi-Beam Data 被引量:1
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作者 FAN Qingkai LI Jianghai +1 位作者 LIU Zhonglan LIU Chiheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第4期810-819,共10页
Fracture-fissure systems found at mid-ocean ridges are dominating conduits for the circulation of metallogenic fluid.Ascertaining the distribution area of active faults on both sides of mid-ocean ridges will provide a... Fracture-fissure systems found at mid-ocean ridges are dominating conduits for the circulation of metallogenic fluid.Ascertaining the distribution area of active faults on both sides of mid-ocean ridges will provide a useful tool in the search for potential hydrothermal vents,thus guiding the exploration of modern seafloor sulfides.Considering the MidAtlantic Ridge 20°N–24°N(NMAR)and North Chile Rise(NCR)as examples,fault elements such as Fault Spacing(?S)and Fault Heave(?X)can be identified and quantitatively measured.The methods used include Fourier filtering of the multi-beam bathymetry data,in combination with measurements of the topographic slope,curvature,and slope aspect patterns.According to the Sequential Faulting Model of mid-ocean ridges,the maximal migration distance of an active fault on either side of mid-ocean ridges—that is,the distribution range of active faults—can be measured.Results show that the maximal migration distance of active faults at the NMAR is 0.76–1.01 km(the distance is larger at the center than at the ends of this segment),and at the NCR,the distribution range of active faults is 0.38–1.6 km.The migration distance of active faults on the two study areas is positively related to the axial variation of magma supply.In the NCR study area,where there is an abundant magma input,the number of faults within a certain distance is mainly affected by the variation of lithospheric thickness.Here a large range of faulting clearly corresponds to a high proportion of magmatism to seafloor spreading near mid-ocean ridges(M)value,and in the study area of the NMAR,there is insufficient magmatism,and the number of faults may be controlled by both lithospheric thickness and magma supply,leading to a less obvious positive correlation between the distribution range of active faults and M. 展开更多
关键词 migration distance of active faults quantitative assessment Mid-Atlantic Ridge North Chile Rise multi-beam bathymetry
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Active earth pressure acting on retaining wall considering anisotropic seepage effect 被引量:4
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作者 HU Zheng YANG Zhong-xuan Stephen Philip WILKINSON 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1202-1211,共10页
This paper presents a general solution for active earth pressure acting on a vertical retaining wall with a drainage system along the soil-structure interface. The backfill has a horizontal surface and is composed of ... This paper presents a general solution for active earth pressure acting on a vertical retaining wall with a drainage system along the soil-structure interface. The backfill has a horizontal surface and is composed of cohesionless and fully saturated sand with anisotropic permeability along the vertical and horizontal directions. The extremely unfavourable seepage flow on the back of the retaining wall due to heavy rainfall or other causes will dramatically increase the active earth pressure acting on the retaining walls, increasing the probability of instability. In this paper, an analytical solution to the Laplace differential governing equation is presented for seepage problems considering anisotropic permeability based on Fourier series expansion method. A good correlation is observed between this and the seepage forces along a planar surface generated via finite element analysis. The active earth pressure is calculated using Coulomb's earth pressure theory based on the calculated pore water pressures. The obtained solutions can be degenerated into Coulomb's formula when no seepage exists in the backfill. A parametric study on the influence of the degree of anisotropy in seepage flow on the distribution of active earth pressure behind the wall is conducted by varying ratios of permeability coefficients in the vertical and horizontal directions,showing that anisotropic seepage flow has a prominent impact on active earth pressure distribution. Other factors such as effective internal friction angle of soils and soil/wall friction conditions are also considered. 展开更多
关键词 active earth pressure Seepage Anisotropic permeability Retaining wall Fourier series expansion Cohesionless soils
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Combined nanosuspensions from two natural active ingredients for cancer therapy with reduced side effects 被引量:1
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作者 Yonghui Qiao Zhihao Wei +8 位作者 Tingting Qin Rufeng Song Zhiqiang Yu Qi Yuan Juan Du Qingbing Zeng Lanlan Zong Shaofeng Duan Xiaohui Pu 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第9期2877-2881,共5页
Tumor drug resistance and systemic side effects of chemotherapeutic drugs are the main reasons for the failure of cancer treatment.In recent years,it was found that some natural active ingredients can reverse MDR and ... Tumor drug resistance and systemic side effects of chemotherapeutic drugs are the main reasons for the failure of cancer treatment.In recent years,it was found that some natural active ingredients can reverse MDR and regulate body immunity to enhance the efficacy and reduce toxicity of chemotherapeutic drugs.In this paper,a new nanosuspensions,HCPT and QUR hybrid nanosuspensions(HQ-NPs),was prepared by the microprecipitation-high pressure homogenization method to reverse tumor drug resistance,reduce toxicity,and increase therapeutic efficacy.The in vitro investigation results showed that HQ-NPs had a unique shape(particle size was about 216.3±5.9 nm),changed crystalline,and different dissolution rates compared with HCPT-NPs and QUR-NPs,which is attributed to the strong intermolecular forces between HCPT and QUR as indicated by the results of the molecule dock.It was verified that the HQ-NPs could double the retention of HCPT in cells and enhance the cytotoxicity to A549/PTX cells in vitro tests compared with HCPT-NPs.We also found that HQ-NPs can significantly enhance the accumulation of HCPT in tumor sites,improve the antitumor activity of HCPT,and protect the immune organs and other normal tissues(P<0.01),compared with HCPT-NPs.Therefore,hybrid nanosuspensions can offer promising potential as the drug delivery system for HCPT and QUR to increase the therapeutic efficacy and reduce the toxicity of HCPT. 展开更多
关键词 Combination therapy Multidrug resistance NANOSUSPENSIONS Antitumor activity IMMUNOMODULATORY
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OPTICALLY ACTIVE AMINO ACIDS WITH HIGHLY BRANCHED SIDE CHAIN(Ⅱ):SYNTHESIS AND RESOLUTION OF RACEMIC 2-ACETAMIDO-7,7-DIMETHYLOCTANOIC ACID AND 2-ACETAMIDO-8,8-DIMETHYLNONANOIC ACID ETHYL ESTERS
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作者 Ya Wen ZHANG De Ben GU +1 位作者 Zong Xuan SHEN Qian ZHANG and Wei ZHANG(Department of Chemistry, Suzhou University. Suzhou. 215006) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第5期373-374,共2页
The title compounds were prepared starting from ethyl acetamidomalonate and resolved by enzmatic hydrolysis giving the corresponding D-and L-amino acids.
关键词 ACIDS AMINO WITH HIGHLY active ACETAMIDO
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Active trachoma prevalence and its associated factors among children aged 1-9 years in rural residents of Lare District, Southwest Ethiopia
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作者 Yitayeh Belsti Sofonias Addis Fekadu Abel Sinshaw Assem 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第11期1756-1764,共9页
AIM:To determine the prevalence of active trachoma and its associated factors among children in Lare District,Southwest Ethiopia,2019.METHODS:A community-based cross-sectional study was conducted.A total of 620 partic... AIM:To determine the prevalence of active trachoma and its associated factors among children in Lare District,Southwest Ethiopia,2019.METHODS:A community-based cross-sectional study was conducted.A total of 620 participants were recruited using a multi-stage sampling technique.A structured questionnaire,torch,and magnifying loupes were used for data collection.The data was entered into epidemiological information and exported to statistical package for social science version 20 for analysis.The bi-variable and multivariable Logistic regression analysis model was fitted to identify factors associated with active trachoma.Odds ratio with a 95%CI was used to show the direction and strength of association between independent and outcome variables.RESULTS:A total of 610 children participated in this study with a response rate of 98.39%.The prevalence of active trachoma was 132(21.60%;95%CI:18.40-24.70).Family size being 6-9(AOR=2.34;95%CI:1.14-5.02),presence of more than two preschool children in a house(AOR=2.04;95%CI:1.12-3.70),open field waste disposal system(AOR=2.62;95%CI:1.00-6.80)and type of latrine being uncovered(AOR=4.12;95%CI:2.00-8.51)were positively associated with active trachoma.On the other side,water consumption being 40-60 liters per day was a protective factor for active trachoma.CONCLUSION:The prevalence of active trachoma is high among children aged 1-9 y in Lare District.Uncovered latrine,open field waste disposal system,family sizes of 6-9,and the presence of more than two preschool children in a house are associated with the occurrence of active trachoma.On the other side,water consumption of 40-60 liters is a protective factor. 展开更多
关键词 active trachoma CHILDREN Lare District Gambella Regional State Ethiopia
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Analytical game strategies for active UAV defense considering response delays
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作者 Xiaopeng Gong Wanchun Chen +3 位作者 Wengui Lei Jinyang Wang Zhongyuan Chen Yunyun Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第12期191-210,共20页
In the realm of aerial warfare,the protection of Unmanned Aerial Vehicles(UAVs) against adversarial threats is crucial.In order to balance the impact of response delays and the demand for onboard applications,this pap... In the realm of aerial warfare,the protection of Unmanned Aerial Vehicles(UAVs) against adversarial threats is crucial.In order to balance the impact of response delays and the demand for onboard applications,this paper derives three analytical game strategies for the active defense of UAVs from differential game theory,accommodating the first-order dynamic delays.The targeted UAV executes evasive maneuvers and launches a defending missile to intercept the attacking missile,which constitutes a UAVMissile-Defender(UMD) three-body game problem.We explore two distinct operational paradigms:the first involves the UAV and the defender working collaboratively to intercept the incoming threat,while the second prioritizes UAV self-preservation,with independent maneuvering away from potentially sacrificial engagements.Starting with model linearization and order reduction,the Collaborative Interception Strategy(CIS) is first derived via a linear quadratic differential game formulation.Building upon CIS,we further explore two distinct strategies:the Informed Defender Interception Strategy(IDIS),which utilizes UAV maneuvering information,and the Unassisted Defender Interception Strategy(UDIS),which does not rely on UAV maneuvering information.Additionally,we investigate the conditions for the existence of saddle point solutions and their relationship with vehicle maneuverability and response agility.The simulations demonstrate the effectiveness and advantages of the proposed strategies. 展开更多
关键词 active defense Unmanned aerial vehicles(UAVs) Three-body game Differential game Analytical game strategy Response delays
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Vehicle Active Damping Control with Considering Time Delay
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作者 Danna Jiang Ying Huang Donghao Hao 《Journal of Beijing Institute of Technology》 EI CAS 2017年第4期449-457,共9页
A model predictive control( MPC) based active damping controller for automotive driveline oscillations with time-delay consideration is proposed. A simplified driveline model considering time delay is modeled and co... A model predictive control( MPC) based active damping controller for automotive driveline oscillations with time-delay consideration is proposed. A simplified driveline model considering time delay is modeled and converted to a linear parameter varying state space equation. Based on the model and model predictive control theory,an active damping controller is designed for drivability and comfortability improvement. In order to verify the designed controller,a driveline with engine is modeled to simulate the tip-in/out driving operation. An MPC active damping controller without considering time delay is simulated together with the proposed controller. The simulation results show that,by adopting the new MPC active damping controller,the vibration of the vehicle is reduced and the drivability and comfortability are improved. 展开更多
关键词 model predictive control (MPC) drive train oscillations active damping control time delay tip-in/out
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OPTICALLY ACTIVE AMINO ACIDS WITH HIGHLY BRANCHED SIDE CHAIN (I) SYNTHESIS OF D- AND L- 2-AMINO-5,5-DIMETHYLHEXANOIC ACID AND 2-AMINO-6,6-DIMETHYLHEPTANOIC ACID
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《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第4期237-238,共2页
The title compounds were prepared by the enzymatic resolution of the corresponding N-acetylated DL-amino acids methyl esters, which were obtained from t-butyl chloride via an 8-step synthesis.
关键词 AMINO-5 5-DIMETHYLHEXANOIC ACID AND 2-AMINO-6 6-DIMETHYLHEPTANOIC ACID AND L OPTICALLY active AMINO ACIDS WITH HIGHLY BRANCHED side CHAIN SYNTHESIS OF D
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