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Ethnopharmacology,chemodiversity,and bioactivity of Cephalotaxus medicinal plants

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Chinese Journal of Natural Medicines 2021年第5期19卷 321-338页

作者： HAO Da-Cheng hou xu-dong GU Xiao-Jie XIAO Pei-Gen GE Guang-Bo Biotechnology Institute School of Environment and Chemical EngineeringDalian Jiaotong UniversityDalian 116028China Institute of Interdisciplinary Integrative Medicine Research Shanghai University of Traditional Chinese MedicineShanghai 201203China Institute of Medicinal Plant Development Chinese Academy of Medical SciencesBeijing 100193China

Cephalotaxus is the only genus of Cephalotaxaceae family,and its natural resources are declining due to habitat fragmentation,excessive exploitation and *** many areas of China,folk herbal doctors traditionally use Cephalotaxus plants to treat innominate swollen poison,many of which are *** only among Han people,but also among minority ethnic groups,Cephalotaxus is used to treat various diseases,e.g.,cough,internal bleeding and cancer in Miao medicine,bruises,rheumatism and pain in Yao medicine,and ascariasis,hookworm disease,scrofula in She medicine,*** values of some Cephalotaxus species and compounds are acknowledged ***,there is a lack of comprehensive review summarizing the ethnomedicinal knowledge o f Cephalotaxus,relevant medicinal phytometabolites and their *** research progresses in ethnopharmacology,chemodiversity,and bioactivities of Cephalotaxus medicinal plants are reviewed and commented *** gaps are pinpointed and future research directions are *** medicinal books,folk medicine books,herbal manuals and ethnomedicinal publications were reviewed for the genus Cephalotaxus(Sanjianshan in Chinese).The relevant data about ethnobotany,phytochemistry,and pharmacology were collected as comprehensively as possible from online databases including Scopus,NCBI PubMed,Bing Scholar,and China National Knowledge Infrastructure(CNKI).44 Cephalotaxus"',and the respective species name were used as keywords in database *** obtained articles of the past six decades were collated and *** Cephalotaxus species are listed in the official medicinal book in *** are used as ethnomedicines by many ethnic groups such as Miao,Yao,dong,She and *** are obtained from traditional applications,and Cephalotaxus phytometabolites are developed into anticancer ***-type alkaloids,homoerythrina-type alkaloids and homoharringtonine(HHT)are abundant in Cephalo

关键词： Cephalotaxus Ethnomedicine Chemodiversity Alkaloids Bioactivity Pharmacology

Effectively improving the extreme-pressure capacity of a class of intercalated zirconium phosphate materials

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Science China(Technological Sciences) 2024年第3期67卷 753-764页

作者： NIU WenXing ZHAO XinRui YUAN Min hou ZhiGuo LIU Lei xu Hong dong JinXiang Shanxi Key Laboratory of Chemical Product Engineering Cllege of Chemical Engineering and TechnologyTaiyuan University of TechnologyTaiyuan 030024China School of Chemical and Environmental Engineering Pingdingshan UniversityPingdingshan 467000China

We studied different long-chain ammonium ions intercalated zirconium phosphate α-ZrP, methylamine intercalated ZrP(MAZrP), tetramethylammonium hydroxide intercalated ZrP(TMAH-ZrP), dodecyltrimethylammonium bromide intercalated ZrP(DTAB-ZrP), and stearyl trimethyl ammonium bromide intercalated ZrP(STAB-ZrP) as grease co-additives in combination with isobutylene sulfide(SIB). The grease with co-additives displayed excellent extreme-pressure and anti-wear ***, the combination of the longest chain ammonium ion intercalated zirconium phosphate, STAB-ZrP/SIB, had the best tribological properties. In comparison to α-ZrP, the advantage of STAB-ZrP was that it did not form a large area of the dense physical film like α-ZrP on the worn surface, but rather gave the SIB a chance to contact with the fresh metal surface to generate a chemical film. Therefore, the sub-micron physical film and nanoscale chemical film always exist side by side on the contact surface during the friction process. This intercalated α-ZrP/SIB additive has great potential for use in harsh operating conditions.

关键词： intercalatedα-ZrP/SIB physical film chemical film tribological properties

Activity Pattern and Habitat Use of Shorebirds in an Artificial Wetland Complex:A Case Study of Breeding Pied Avocet in the Yellow River Delta,China

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Chinese Geographical Science 2024年第4期34卷 618-630页

作者： LI dong LI Bin xu He FAN Chao WU Yang ZHANG Yuxin hou Xiyong Yantai Institute of Coastal Zone Research Chinese Academy of SciencesYantai 264003China Beijing VMinFull Limited Beijing 100086China CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China University of Chinese Academy of Sciences Beijing 100049China School of Information Engineering Zhejiang Ocean UniversityZhoushan 316022China Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China

With the loss of substantial natural wetlands in coastal zones,artificial wetlands provide alternative habitats for many *** management of artificial wetlands used by shorebirds plays an important role in maintaining the stability of shorebird *** tracking technique can obtain high-precision location information of individuals day and night,providing a good technical support for the study of quantitative relationship between waterfowls and their *** this study,satellite tracking method,Remote Sensing(RS)and Geographic Information System(GIS)technology were used to analyze the activity pattern and habitat utilization characteristics of Pied Avocet during breeding period in an artificial wetland complex in the Yellow River Delta(YRD),*** results showed that the breeding Pied Avocets had a small range of activity,with a total core and main home range of 33.10 km^(2) and 216.30 km^(2),*** species tended to forage in the pond and salt pan during the day and night,respectively,with an unfixed staying time in the breeding *** distance between breeding ground and feeding ground was less than 6 *** is emphasized that in addition to improving the conditions of the remaining natural habitats,effective managing artificial habitats is a priority for shorebird *** research could provide reference for the management of artificial wetlands in coastal zones and supply technique support for the protection of shorebirds and their habitats,and alleviate human-bird conflicts and sustainable development of coastal zones.

关键词： satellite tracking home range habitat use artificial wetland coastal zone Pied Avocet Yellow River Delta China

Pancreatic lipase inhibitory constituents from Fructus Psoraleae

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Chinese Journal of Natural Medicines 2020年第5期18卷 369-378页

作者： hou xu-dong SONG Li-Lin CAO Yun-Feng WANG Yi-Nan Zhou Qi FANG Sheng-Quan WU Da-Chang ZANG Shi-Zhu CHEN Lu BAI Yue GE Guang-Bo hou Jie College of Basic Medical Sciences Dalian Medical UniversityDalian 116000China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116000China Translational Medicine Center Yueyang Hospital of Integrated Traditional Chinese and Western Medicine&Institute of Interdisciplinary Integrative Medicine ResearchShanghai University of Traditional Chinese MedicineShanghai 200000China Dalian Runsheng Kangtai Medical Laboratory Co.Ltd. Dalian 116000China

Pancreatic lipase(PL), a crucial enzyme in the digestive system of mammals, has been proven as a therapeutic target to prevent and treat obesity. The purpose of this study is to evaluate and characterize the PL inhibition activities of the major constituents from Fructus Psoraleae(FP), one of the most frequently used Chinese herbs with lipid-lowering activity. To this end, a total of eleven major constituents isolated from Fructus Psoraleae have been obtained and their inhibition potentials against PL have been assayed by a fluorescence-based assay. Among all tested compounds, isobavachalcone, bavachalcone and corylifol A displayed strong inhibition on PL(IC50 < 10 μmol·L-1). Inhibition kinetic analyses demonstrated that isobavachalcone, bavachalcone and corylifol A acted as mixed inhibitors against PL-mediated 4-methylumbelliferyl oleate(4-MUO) hydrolysis, with the Ki values of 1.61, 3.77 and 10.16μmol·L-1, respectively. Furthermore, docking simulations indicated that two chalcones(isobavachalcone and bavachalcone) could interact with the key residues located in the catalytic cavity of PL via hydrogen binding and hydrophobic interactions. Collectively, these finding provided solid evidence to support that Fructus Psoraleae contained bioactive compounds with lipid-lowering effects via targeting PL, and also suggested that the chalcones in Fructus Psoraleae could be used as ideal leading compounds to develop novel PL inhibitors.

关键词： Pancreatic lipase Fructus Psoraleae Inhibition potential Isobavachalcone Bavachalcone

Compositionally graded high-voltage P2-type cathode with superior structural stability and redox kinetics for advanced Na-ion batteries

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Nano Research 2024年第4期17卷 2755-2762页

作者： Peiyu hou Mohan dong Zhenbo Sun Feng Li School of Physics and Technology University of JinanJinan 250022China

Layered P2-type cathodes with high voltage,large capacity,and easy synthesis show great potential for developing sodium(Na)-ion batteries(NIBs).However,the P2–O2 phase transition makes their structural degradation and the Na^(+)/vacancy ordering lowers their redox ***,we rationally propose a compositionally graded P2-type cathode,where nickel(Ni)and manganese(Mn)fractions decrease gradually,and cobalt(Co)content increases contiguously from the inside to the outside of a secondary *** these particles,the Ni/Mn-based compound delivers high capacity and high *** the surface of particles,the Co/Mn-based solid solution offers a stable buffer *** from these synergistic effects,this graded P2-type cathode shows the elimination of P2–O2 transformation even when charged to 4.4 V,which enables good structural stability,maintaining capacity retention reaching~80%within 300 ***,the Na^(+)/vacancy ordering superstructure is further suppressed,and the Na^(+)diffusion kinetics is significantly *** proposed graded structure with optimized chemical composition offers a new perspective for eliminating the unwanted phase transition and thus enhancing the electrochemistry of high-voltage layered cathodes for advanced NIBs.

关键词： Na-ion battery P2-type cathode composition regulation phase transition redox stability

Investigation of high rate mechanical flow followed by ignition for high-energy propellant under dynamic extrusion loading

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Defence Technology（防务技术） 2024年第2期32卷 336-347页

作者： Liying dong Yanqing Wu Kun Yang Xiao hou State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Investigating the ignition response of nitrate ester plasticized polyether(NEPE) propellant under dynamic extrusion loading is of great significant at least for two cases. Firstly, it helps to understand the mechanism and conditions of unwanted ignition inside charged propellant under accident ***, evaluates the risk of a shell crevice in a solid rocket motor(SRM) under a falling or overturning scene. In the present study, an innovative visual crevice extrusion experiment is designed using a dropweight apparatus. The dynamic responses of NEPE propellant during extrusion loading, including compaction and compression, rapid shear flow into the crevice, stress concentration, and ignition reaction, have been firstly observed using a high-performance high-speed camera. The ignition reaction is observed in the triangular region of the NEPE propellant sample above the crevice when the drop weight velocity was 1.90 m/s. Based on the user material subroutine interface UMAT provided by finite element software LS-DYNA, a viscoelastic-plastic model and dual ignition criterion related to plastic shear dissipation are developed and applied to the local ignition response analysis under crevice extrusion conditions. The stress concentration occurs in the crevice location of the propellant sample, the shear stress is relatively large, the effective plastic work is relatively large, and the ignition reaction is easy to occur. When the sample thickness decreases from 5 mm to 2.5 mm, the shear stress increases from 22.3 MPa to 28.6 MPa, the critical value of effective plastic work required for ignition is shortened from 1280 μs to 730 μs, and the triangular area is easily triggering an ignition reaction. The propellant sample with a small thickness is more likely to stress concentration, resulting in large shear stress and effective work, triggering an ignition reaction.

关键词： NEPE propellant Crevice extrusion Shear flow Sample thickness Ignition reaction

Mechanical Behavior and Failure Mechanism of an As-Extruded Mg-11wt%Y Alloy at Elevated Temperature

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 969-981页

作者： Lan Zhang Dao-Kui xu Bao-Jie Wang Cui-Lan Lu Shuo Wang Xiang-Bo xu dong-Liang Wang Xin Lv En-hou Han School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819China Institute of Corrosion Science and Technology Guangdong510070China

Through carrying out the high-temperature tensile experiments on an as-extruded Mg-11wt%Y alloy at 350℃,400℃,450℃,500℃and 550℃,the mechanical behavior and fracture mechanisms at elevated temperatures are investigated and *** results show that with the increase of temperature,the yield strength and ultimate tensile strength of the alloy increase at first and then decrease,while that the elongation ratio decreases firstly and then *** the sample being tested at 350℃,the values of yield strength,ultimate tensile strength and the elongation ratio are 188 MPa,266 MPa and 11%,*** 400℃,the yield strength and ultimate tensile strength reach the maximum values of,respectively,198 MPa and 277 MPa,but the elongation ratio is the lowest and its value is only 8%.When the applied temperature is increased to 550℃,the values of yield strength and ultimate tensile strength,respectively,decrease to 140 MPa and 192 MPa and the elongation ratio increases to 38%.Failure analysis demonstrates that the fracture surfaces of different samples are mainly composed of plastic dimples and exhibit the typical characteristic of ductile *** observation to the fracture side surfaces indicates that at the temperatures of 350℃and 400℃,microcracks mainly initiate in the interior of Mg_(24)Y_(5)*** the temperatures are 450℃,500℃and 550℃,the cracks preferentially initiate at the Mg_(24)Y_(5)/α-Mg interfaces.

关键词： Mg-Y alloy High-temperature tensile properties Fracture mechanism Failure analysis

Dual Frequency Transformer for Efficient SDR-to-HDR Translation

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Machine Intelligence Research 2024年第3期21卷 538-548页

作者： Gang xu Qibin hou Ming-Ming Cheng Tianjin Media Computing Center College of Computer ScienceNankai UniversityTianjin300000China

The SDR-to-HDR translation technique can convert the abundant standard-dynamic-range (SDR) media resources to high-dynamic-range (HDR) ones, which can represent high-contrast scenes, providing more realistic visual experiences. While recent vision Transformers have achieved promising performance in many low-level vision tasks, there are few works attempting to leverage Transformers for SDR-to-HDR translation. In this paper, we are among the first to investigate the performance of Transformers for SDR-to-HDR translation. We find that directly using the self-attention mechanism may involve artifacts in the results due to the inappropriate way to model long-range dependencies between the low-frequency and high-frequency components. Taking this into account, we advance the self-attention mechanism and present a dual frequency attention (DFA), which leverages the self-attention mechanism to separately encode the low-frequency structural information and high-frequency detail information. Based on the proposed DFA, we further design a multi-scale feature fusion network, named dual frequency Transformer (DFT), for efficient SDR-to-HDR translation. Extensive experiments on the HDRTV1K dataset demonstrate that our DFT can achieve better quantitative and qualitative performance than the recent state-of-the-art methods. The code of our DFT is made publicly available at https://***/CS-Gangxu/DFT.

关键词： Standard-dynamic-range to high-dynamic-range(SDR-to-HDR)translation Transformer dual frequency attention(DFA) frequency-aware feature decomposition efficient model

Spatiotemporal variation and freeze-thaw asymmetry of Arctic sea ice in multiple dimensions during 1979 to 2020

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Acta Oceanologica Sinica 2024年第3期43卷 102-114页

作者： Yu Guo Xiaoli Wang He xu Xiyong hou CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Shandong Key Laboratory of Coastal Environmental Processes Yantai 264003China University of Chinese Academy of Sciences Beijing 100049China

Arctic sea ice is broadly regarded as an indicator and amplifier of global climate *** rapid changes in Arctic sea ice have been widely ***,the spatiotemporal changes in the horizontal and vertical dimensions of Arctic sea ice and its asymmetry during the melt and freeze seasons are rarely quantified simultaneously based on multiple sources of the same long time *** this study,the spatiotemporal variation and freeze-thaw asymmetry of Arctic sea ice were investigated from both the horizontal and vertical dimensions during 1979–2020 based on remote sensing and assimilation *** results indicated that Arctic sea ice was declining at a remarkably high rate of–5.4×10^(4) km^(2)/a in sea ice area(SIA)and–2.2 cm/a in sea ice thickness(SIT)during 1979 to 2020,and the reduction of SIA and SIT was the largest in summer and the smallest in ***,compared with other sub-regions,SIA showed a sharper declining trend in the Barents Sea,Kara Sea,and East Siberian Sea,while SIT presented a larger downward trend in the northern Canadian Archipelago,northern Greenland,and the East Siberian *** to the seasonal trend of sea ice on sub-region scale,the reduction rate of SIA exhibited an apparent spatial heterogeneity among seasons,especially in summer and winter,i.e.,the sub-regions linked to the open ocean exhibited a higher decline rate in winter;however,the other sub-regions blocked by the coastlines presented a greater decline rate in *** SIT,the sub-regions such as the Beaufort Sea,East Siberian Sea,Chukchi Sea,Central Arctic,and Canadian Archipelago always showed a higher downward rate in all ***,a striking freeze-thaw asymmetry of Arctic sea ice was also *** sea ice changes in different dimensions,sea ice over most regions in the Arctic showed an early retreat and rapid advance in the horizontal dimension but late melting and gradual freezing in the vertical *** amount of sea ice me

关键词： Arctic sea ice sea ice area sea ice thickness spatiotemporal variation freeze-thaw asymmetry