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Surface pollen and modern vegetation in Southern Xinjiang,China

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Science China Earth Sciences 2024年第2期67卷 510-530页

作者： Yun ZHANG lixin CHEN Yaoyao XI Zhaochen KONG Xianguo QIAO State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102China Institute of Botany Chinese Academy of SciencesBeijing100093China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China School of Geosciences and Resources China University of Geosciences(Beijing)Beijing100083China

The study of modern pollen,and vegetation can improve the accuracy of paleoenvironmental reconstruction based on fossil pollen data.A total of 188 pollen surface samples were collected from Southern Xinjiang(34°00’–43°00’N,74°00’–94°00’E)in China,with an elevation range of 888–4530 *** pollen and vegetation were studied in the northern region of the Kunlun Mountains and the southern region of the Tianshan *** results showed that the surface pollen assemblages on the southern slope of the Tianshan Mountains(3530–1124 m)were divided into three pollen zones,namely,montane steppe,montane desert steppe,and montane *** zones were dominated by Artemisia,Chenopodiaceae,and Ephedra *** surface pollen assemblages in the eastern Pamir Plateau(4530–1287 m)could be divided into alpine meadow,montane desert steppe,and montane desert zones,which were predominantly characterized by Artemisia,Chenopodiaceae,and Asteraceae ***,the Southern Tarim Basin(3548–888 m)comprised montane desert steppe and montane desert zones,which was dominated by Artemisia and Chenopodiaceae *** geographic distribution of the surface pollen sites obtained using ArcGIS,the R-value,and Pearson correlation analyses indicated that the over-represented Picea and Pinus pollen were of external origin and were transported by wind,water(rivers),and ice(glacier movement).Over-representation of Ephedra and Nitraria pollen was mainly distributed in the montane desert and desert steppe zones,*** from Chenopodiaceae and Artemisia were over-represented and broadly distributed across Southern *** pollen was concentrated in areas with walnut trees,strongly indicating the presence of local parent *** to the Hybrid Singleparticle Lagrangian Integrated Trajectory model,more Pinus pollen was transported to the Pamir region by external airflows during spring and summer,resulting in its higher surface pollen *** elucidating t

关键词： Surface pollen Vegetation Distribution Picea Southern Xinjiang

Tube-based robust reinforcement learning for autonomous maneuver decision for UCAVs

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Chinese Journal of Aeronautics 2024年第7期37卷 391-405页

作者： lixin WANG Sizhuang ZHENG Haiyin PIAO Changqian LU Ting YUE Hailiang LIU School of Aeronautical Science and Engineering Beihang UniversityBeijing 100191China Shenyang Aircraft Design&Research Institute Shenyang 110035China

Reinforcement Learning(RL)algorithms enhance intelligence of air combat AutonomousManeuver Decision(AMD)policy,but they may underperform in target combat environmentswith *** enhance the robustness of the AMD strategy learned by RL,thisstudy proposes a Tube-based Robust RL(TRRL)***,this study introduces a tube todescribe reachable trajectories under disturbances,formulates a method for calculating tubes basedon sum-of-squares programming,and proposes the TRRL algorithm that enhances robustness byutilizing tube size as a quantitative ***,this study introduces offline techniques forregressing the tube size function and establishing a tube library before policy learning,aiming toeliminate complex online tube solving and reduce the computational burden during ***,an analysis of the tube library demonstrates that the mitigated AMD strategy achievesgreater robustness,as smaller tube sizes correspond to more cautious *** finding highlightsthat TRRL enhances robustness by promoting a conservative *** effectively balanceaggressiveness and robustness,the proposed TRRL algorithm introduces a“laziness factor”as aweight of ***,combat simulations in an environment with disturbances confirm thatthe AMD policy learned by the TRRL algorithm exhibits superior air combat performance comparedto selected robust RL baselines.

关键词： Air combat Autonomous maneuver decision Robust reinforcement learning Tube-based algorithm Combat simulation

Potential morphological responses of an artificial beach to a flood in extreme events: field observation and numerical modelling

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Acta Oceanologica Sinica 2024年第7期43卷 78-92页

作者： Jiadong Fan Cuiping Kuang Xuejian Han lixin Gong Huixin Liu Jiabo Zhang College of Civil Engineering Tongji UniversityShanghai 200082China The Eighth Geological Brigade Hebei Geological and Mineral Exploration Development BureauQinhuangdao 066001China Marine Ecological Restoration and Smart Ocean Engineering Research Center of Hebei Province Qinhuangdao 066001China

Conch Island is a typical artificial island at the Tanghe Estuary in Bohai Sea,*** improve natural environment and boost local tourism,beach nourishment will be applied to its north-western *** projected beach is landward and opposite to the Jinmeng Bay ***,with climate changes,frequent heavy rainfalls in Hebei Province rise flood hazards at the Tanghe *** this circumstance,potential influences on the projected beach of a flood are investigated for sustainable managements.A multi-coupled model is established and based on the data from field observations,where wave model,flow model and multifraction sediment transport model are *** addition,the impacts on the projected beach of different components in extreme events are discussed,including the spring tides,storm winds,storm waves,and sediment *** numerical results indicate the following result.(1)Artificial islands protect the coasts from erosion by obstructing landward waves,but rise the deposition risks along the target shore.(2)Flood brings massive sediment inputs and leads to scours at the estuary,but the currents with high sediment concentration contribute to the accretions along the target shore.(3)The projected beach mitigates flood actions and reduces the maximum mean sediment concentration along the target shore by 20%.(4)The storm winds restrict the flood and decrease the maximum mean sediment concentration by 21%.With the combined actions of storm winds and waves,the maximum value further declines by 38%.(5)A quadratic polynomial relationship between the deposition depths and the maximum sediment inputs with flood is established for estimations on the potential morphological changes after the flood process in extreme *** the uncertainty of estuarine floods,continuous monitoring on local hydrodynamic variations and sediment characteristics at Tanghe Estuary is necessary.

关键词： beach nourishment flood artificial island sediment transport extreme events storm

Yolk free egg substitute improves the serum phospholipid profile of mice with metabolic syndrome based on lipidomic analysis

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Food Science and Human Wellness 2024年第1期13卷 482-493页

作者： Zhihui Yu Lingyu Fan Fei Tai lixin Zhang Xiaoyu Zhang Yisheng Chen College of Food Science and Engineering Shanxi Agricultural UniversityTaigu 030801China Insitute of Food Nutrition and Safety Shanxi Agricultural UniversityTaiyuan 030031China Shanxi Key Laboratory of Edible Fungi for Loess Plateau Taigu 030801China

In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively *** were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with whole egg group(WE),HFD with free-yolk egg substitute group(YFES),and HFD with lovastatin group(Lov).Main biochemical indexes and a non-targeted lipidomic analysis were employed to insight the lipid profile changes in *** was revealed that WE could significantly improve serum biochemical indexes by reducing body weight,low-density lipoprotein cholesterol(LDL-C)and total cholesterol(TC),while increasing high-density lipoprotein *** exhibited remarkably better performance in increasing phosphatidylglycerol and phosphatidic acids,while decreasing phosphatidylinositol than WE.A total of 50 differential lipids biomarkers tightly related to glycerophospholipids metabolism were screened *** C18:2 and C12:1,SM(d18:0/12:0),and SM(d18:1/14:1)were significantly upregulated in YFES compared to *** reduced expression of SREBP-1c and Cpt1a,while did not affect the expression of PPAR-α.Sphingomyelin biomarkers were positively related to the TC(|r|>0.6),while PPAR-αwas negatively correlated with triglyceride and LDL-C *** sum up,YFES attenuated HFD-induced Met S by improving the serum phospholipids,which account for its modulation of glycerophospholipid metabolism.

关键词： Metabolic syndrome Whole egg Yolk free egg substitute Serum Lipidomics

Identification of aircraft longitudinal aerodynamic parameters using an online corrective test for wind tunnel virtual flight

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Chinese Journal of Aeronautics 2024年第9期37卷 261-275页

作者： Shang TAI Chen BU Yanling WANG Ting YUE Hailiang LIU lixin WANG School of Aeronautical Science and Engineering Beihang UniversityBeijing 100191China AVIC Aerodynamics Research Institute Harbin 150001China

The identification of aerodynamic parameters is accomplished through the test data of the dynamic movement of scaled aircraft models flying dynamically in wind tunnel,which can real-ize the accurate acquisition of the aerodynamic model of the aircraft in the preliminary stage for aircraft design,and it is of great significance for improving the efficiency of aircraft ***-ever,the translational motion of the test model in the wind tunnel virtual flight is subject to con-straints that result in distinct flight dynamics compared to free *** constraints have implications for the accuracy of aerodynamic derivatives obtained through the identification of wind tunnel test *** this issue in mind,the research studies the differences in longitudinal dynamic characteristics between unconstrained free flight and wind tunnel virtual flight,and inno-vatively proposes an online correction test based wind tunnel virtual flight test *** lon-gitudinal trajectory and velocity changes of the model are solved online by the aerodynamic forces measured during the test,and then the coupled relationship between aircraft translation and rota-tion is used to correct the model's pitch attitude motion *** the first time,the problem of solving the data approximation for free flight has been solved,eliminating the difference between the dynamics of wind tunnel virtual flight and free flight,and improving the accuracy of the aero-dynamic derivative identification *** experiment's findings show that accurate aerodynamic derivatives can be identified based on the online correction test data,and the observed behaviour of the identified motion model has similarities to that of the free flight motion model.

关键词： Wind tunnels Displacement constraints Online solution Flightcontrol law Aerodynamic parameter identification

Do nocturnal birds use acoustic and visual cues to avoid predation by bats?

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Integrative Zoology 2024年第3期19卷 524-537页

作者： lixin GONG Huan WU Zhiqiang WANG Hui WU Jiang FENG Tinglei JIANG Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal UniversityChangchunChina Key Laboratory of Vegetation Ecology of Education Ministry Institute of Grassland ScienceNortheast Normal UniversityChangchunChina College of Life Science Jilin Agricultural UniversityChangchunChina

Anti-predation strategies are critical to animal survival and are fundamental to deciphering predator–prey *** an important defense strategy,sensory predator detection(such as through acoustic and visual cues)enables animals to assess predation risk and execute predator-avoidance behavior;however,there are limited studies on the anti-predation behavior of nocturnal *** prey of bats provides an excellent representative system for examining the anti-predation behavior of nocturnal ***,we broadcasted different types of echolocation calls of the bird-eating bat Ia io to two wild passerine birds,namely,Zosterops japonicus and Sinosuthora webbiana,that are preyed upon by ***,and presented the birds with individual bats under different light *** results showed that both bird species were able to perceive the low-frequency audible portion of the bats’echolocation calls;however,they did not exhibit escape responses to the acoustic *** the dark and under moonlit conditions,both bird species were unable to respond to active bats at close range and the birds only exhibited evasive flight behavior when bats approached or touched *** results suggest that nocturnal passerine birds may not be able to use acoustic or visual cues to detect bats and adopt evasive maneuvers to avoid *** work suggests that bat predation pressure may not elicit primary predator-avoidance responses in nocturnal passerine *** results provide new insights into the anti-predation behavior of nocturnal animals.

关键词： anti-predation behavior nocturnal animals sensory cues sensory defenses

Human extracellular matrix(ECM)-like collagen and its bioactivity

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Regenerative Biomaterials 2024年第4期3卷 14-26页

作者： Hui Zhou Wenwei Li lixin Pan Tianci Zhu Teng Zhou E.Xiao Qiang Wei State Key Laboratory of Polymer Materials and Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China Hunan Maybio Bio-Pharmaceutical Co. LtdChangsha 410000China

Collagen,the most abundant structural protein in the human extracellular matrix(ECM),provides essential support for tissues and guides tissue *** its widespread use in tissue engineering,there remains uncertainty regarding the optimal selection of collagen ***-derived sources pose challenges such as immunogenicity,while the recombinant system is hindered by diminished *** this study,we hypothesized that human ECM-like collagen(hCol)could offer an alternative for tissue *** this study,a facile platform was provided for generating hCol derived from mesenchymal stem cells with a hierarchical structure and biochemical properties resembling native *** results further demonstrated that hCol could facilitate basal biological behaviors of human adipose-derived stem cells,including viability,proliferation,migration and adipocyte-like ***,it could promote cutaneous wound *** to its high similarity to native collagen and good bioactivity,hCol holds promise as a prospective candidate for in vitro and in vivo applications in tissue engineering.

关键词： extracellular matrix native-like collagen cell-derived matrix hierarchical structure

Mechanism of high Li-ion conductivity in poly(vinylene carbonate)-poly(ethylene oxide)cross-linked network based electrolyte revealed by solid-state NMR

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Journal of Energy Chemistry 2024年第6期93卷 377-383,I0010页

作者： Fan Li Tiantian Dong Yi Ji lixin Liang Kuizhi Chen Huanrui Zhang Guanglei Cui Guangjin Hou State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyCollaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101ShandongChina

Solid polymer electrolytes(SPEs)have become increasingly important in advanced lithium-ion batteries(LIBs)due to their improved safety and mechanical properties compared to organic liquid ***-linked polymers have the potential to further improve the mechanical property without trading off Li-ion *** this study,focusing on a recently developed cross-linked SPE,i.e.,the one based on poly(vinylene carbonate)-poly(ethylene oxide)cross-linked network(PVCN),we used solid-state nuclear magnetic resonance(NMR)techniques to investigate the fundamental interaction between the chain segments and Li ions,as well as the lithium-ion *** utilizing homonuclear/heteronuclear correlation,CP(cross-polarization)kinetics,and spin-lattice relaxation experiments,etc.,we revealed the structural characteristics and their relations to lithium-ion *** is found that the network formation prevents poly(ethylene oxide)chains from crystallization,which could create sufficient space for segmental tumbling and Li-ion co nductio *** such,the mechanical property is greatly improved with even higher Li-ion mobilities compared to the poly(vinylene carbonate)or poly(ethylene oxide)based SPE analogues.

关键词： ssNMR Lithium-ion mobility Cross-link Solid polymer electrolyte

Multiresponsive,easy-reversible,and dual-visual Pt(Ⅱ)salt nanostructures for advanced anti-counterfeiting application

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Nano Research 2024年第1期17卷 372-381页

作者： Zhen Su§ Depeng Li§ lixin Zhang Si Tian Yuhong Su Xiaoyun Hu Duan Xiong Qingqing Guan Key Laboratory of Oil and Gas Fine Chemicals Ministry of Education College of Chemical EngineeringXinjiang UniversityUrumqi 830017China

Smart materials that integrate multi-stimuli response,full reversibility,and dual-visual read-out channel are highly desired for anticounterfeiting and information encryption ***,we developed a multiresponsive perchlorate terpyridyl Pt(Ⅱ)nano complex which could undergo fully reversible conversion between three forms stimulated by water or formaldehyde molecule due to the extent of Pt–Pt ***,a dual-visual channel,i.e.,the colorimetric channel changed from yellow to orange or red and the corresponding luminescent channel from orange to orange-red or red,has also been *** weak and equivalent strength of ion-dipole interaction and hydrogen bond that generated between formaldehyde/water and Pt(II)salt result in the easy-control reversibility between the three ***,by introducing different polymer matrices,1Cl·ClO_(4)@PMMA(1Cl·ClO_(4):[Pt(tpy)Cl]·ClO4,tpy:2,2':6',2''-terpyridine),PMMA:poly(methyl methacrylate))and 1Cl·ClO4@PVA(PVA:polyvinyl alcohol)are successfully constructed,which exhibit different reversible behaviors since the PMMA and PVA matrix exert different influences on the strength of *** smart Pt(II)salt nanostructures present great potential for high-security-level anticounterfeiting application.

关键词： Pt(II)complex multiresponse reversibility anticounterfeiting information encryption