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Late Oligocene fossil acorns and nuts of Quercus section Cyclobalanopsis from the Nanning Basin,Guangxi,South China

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Plant Diversity 2023年第4期45卷 434-445页

作者： Xiao-Yan Liu Han-Zhang Song Xin-Kai Wu jia-rong hu Wei-Ye huang Cheng Quan jian-hua Jin State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources School of Life SciencesSun Yat-sen UniversityGuangzhou 510275China School of Geography South China Normal UniversityGuangzhou 510631China State Key Laboratory of Biocontrol School of EcologySun Yat-sen UniversityGuangzhou 510275China School of Earth Science and Resources Chang'an UniversityXi'an 710054China

Quercus is the largest genus within the Fagaceae and has a rich fossil *** of the fossil material is attributed to the subgenus Quercus based on leaves,pollen or rarely acorns and *** records of *** Cyclobalanopsis characterized by ring-cupped acorns are relatively few and especially those described based on nuts are *** this study,we described four new species of Quercus section Cyclobalanopsis based on mummified acorns and nuts:*** *** et *** ***.,*** *** et *** ***.,*** *** et *** *** *** *** et *** *** species closely resemble the extant species ***,***,***,and *** occurrence of *** Cyclobalanopsis in the Oligocene stratum of Guangxi,South China,suggests that the section has diversified within its extant distribution center since the *** combining records from other areas,we propose that the section first appeared in the middle Eocene of East Asia(Sino-Japan),has diversified in situ with a few elements scattering into West Asia and southern Europe since the Oligocene and Pliocene,respectively,and finally became restricted in East Asia since the *** indicates that the section originated and diversified in East Asia,before spreading into West Asia no later than the Oligocene and into southern Europe by the *** it disappeared from South Europe and West Asia due to the appearance of the(summer dry)Mediterranean climate and widespread cooling during the Pleistocene.

关键词： Quercus section Cyclobalanopsis Fossil acorn and nut Oligocene Guangxi South China

A multifunctional shear apparatus for rocks subjected to true triaxial stress and high temperature in real-time

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3524-3543页

作者： Jun Zhao Xia-Ting Feng jia-rong Wang Liang hu Yue Guo Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China Key Laboratory of Liaoning Province on Deep Engineering and Intelligent Technology Northeastern UniversityShenyang110819China

Deep engineering disasters,such as rockbursts and collapses,are more related to the shear slip of rock joints.A novel multifunctional device was developed to study the shear failure mechanism in *** this device,the complete shearedeformation process and long-term shear creep tests could be performed on rocks under constant normal stiffness(CNS)or constant normal loading(CNL)conditions in real-time at high temperature and true-triaxial *** the research and development process,five key technologies were successfully broken through:(1)the ability to perform true-triaxial compressioneshear loading tests on rock samples with high stiffness;(2)a shear box with ultra-low friction throughout the entire stress space of the rock sample during loading;(3)a control system capable of maintaining high stress for a long time and responding rapidly to the brittle fracture of a rock sample as well;(4)a refined ability to measure the volumetric deformation of rock samples subjected to true triaxial shearing;and(5)a heating system capable of maintaining uniform heating of the rock sample over a long *** developing these technologies,loading under high true triaxial stress conditions was *** apparatus has a maximum normal stiffness of 1000 GPa/m and a maximum operating temperature of 300*** differences in the surface temperature of the sample are constant to within5*** types of true triaxial shear tests were conducted on homogeneous sandstone to verify that the apparatus has good performance and *** results show that temperature,lateral stress,normal stress and time influence the shear deformation,failure mode and strength of the *** novel apparatus can be reliably used to conduct true-triaxial shear tests on rocks subjected to high temperatures and stress.

关键词： True-triaxial shear apparatus Rocks Complete shear stressedeformation process Creep Real-time high-temperature

Effects of Acupotomy on Immobilization-Induced Gastrocnemius Contracture and Fibrosis in Rats via Wnt/β-Catenin Signaling

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Chinese Journal of Integrative Medicine 2024年第7期30卷 633-642页

作者： hu Rui PAN Jun-kang LI jia-hui ZHANG Han LI Shao-rong ZHANG Yi School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese MedicineBeijing100029China Acupuncture Department Kunming Municipal Hospital of Traditional Chinese MedicineKunming650500China

Objective To determine whether acupotomy ameliorates immobilization-induced muscle contracture and fibrosis via Wnt/β-catenin signaling *** Thirty Wistar rats were randomly divided into 5 groups(n=6)by a random number table,including control,immobilization,passive stretching,acupotomy,and acupotomy 3 weeks(3-w)*** rat model of gastrocnemius contracture was established by immobilizing the right hind limb in plantar flexion for 4 *** in the passive stretching group received passive stretching at gastrocnemius,a daily series of 10 repetitions for 30 s each at 30-s intervals for 10 consecutive *** in the acupotomy and acupotomy 3-w groups received acupotomy once and combined with passive stretching at gastrocnemius a daily series of 10 repetitions for 30 s each at 30-s intervals for 10 consecutive ***,rats in the acupotomy 3-w group were allowed to walk freely for 3 weeks after 10-day *** treatment,range of motion(ROM),gait analysis[i.e.,paw area,stance/swing and maximum ratio of paw area to paw area duration(Max dA/dT)],gastrocnemius wet weight and the ratio of muscle wet weight to body weight(MWW/BW)were *** morphometric and muscle fiber cross-sectional area(CSA)were assessed by hematoxylin-eosin ***-related mRNA expressions(i.e.,Wnt 1,β-catenin,axin-2,α-smooth muscle actin,fibronectin,and types I and III collagen)were measured using real-time quantitative polymerase chain *** 1,β-catenin and fibronectin concentrations were measured by enzyme-linked immunosorbent *** I and III collagen in the perimysium and endomysium were analyzed using *** Compared with the control group,ROM,gait function,muscle weight,MWW/BW and CSA were significantly decreased in the immobilization group(all P<0.01),while protein levels of types I and III collagen,Wnt 1,β-catenin,fibronectin and mRNA levels of fibrosis-related genes were obviously increased(all P<0.01).Tr

关键词： acupotomy immobilization muscle contracture muscle fibrosis Wnt/β-catenin signaling

Coupled conditional nonlinear optimal perturbations and their application to ENSO ensemble forecasts

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Science China Earth Sciences 2024年第3期67卷 826-842页

作者： Wansuo DUAN Lei hu rong FENG LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Limitations are existed in current ensemble forecasting initial perturbation methods for describing the interactions among various spheres of the Earth system. In this study, a new method is proposed, namely, the coupled conditional nonlinear optimal perturbation(C-CNOP) method, which incorporates multisphere interactions much appropriately. The El Nino-Southern Oscillation(ENSO) is a typical ocean-atmosphere “coupling”(or “interaction”) phenomenon. The C-CNOP method is applied to ensemble forecasting of ENSO. It is demonstrated that the C-CNOP method can generate coupled initial perturbations(CPs) that appropriately consider initial ocean-atmosphere coupling uncertainty for ENSO ensemble forecasts. Results reveal that the CPs effectively improve the ability of ENSO ensemble-mean forecasts in both temporal variability of Nio3.4 sea surface temperature anomalies(SSTAs) and spatial variability of ENSO mature-phase SSTAs. Notably, despite the weakest ocean-atmosphere coupling strength in the tropical Pacific occurring during the boreal spring and summer, CPs still capture the uncertainties of this weak coupling when ENSO predictions are initialized at these seasons. This performance of CPs significantly suppresses the rapid increase of ENSO prediction errors due to the high ocean-atmosphere coupling instability during these seasons, and thus effectively extends the lead time of skillful ENSO forecasting. Hence, the C-CNOP method is a suitable initial perturbation approach for ENSO ensemble forecast that can describe initial ocean-atmosphere coupling uncertainty. It is expected that the CCNOP method plays a significant role in predictions of other high-impact climate phenomena, and even future Earth system predictions.

关键词： Ensemble forecast Multisphere interaction Initial perturbations ENSO

Capillary Property of Entangled Porous Metallic Wire materials and Its Application in Fluid Buffers:Theoretical Analysis and Experimental Study

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Defence Technology（防务技术） 2024年第1期31卷 400-416页

作者： Yu Tang Yiwan Wu hu Cheng rong Liu Engineering Research Center for Metal Rubber School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350156China AECC Guizhou Liyang Aviation Power Co. LTDGuiyang 550014China College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou 350156China

Strong impact does serious harm to the military industries so it is necessary to choose reasonable cushioning material and design effective buffers to prevent the impact of *** on the capillary property entangled porous metallic wire materials(EPMWM),this paper designed a composite buffer which uses EPMWM and viscous fluid as cushioning materials under the low-speed impact of the recoil force device of weapon equipment(such as artillery,mortar,etc.).Combined with the capillary model,porosity,hydraulic diameter,maximum pore diameter and pore distribution were used to characterize the pore structure characteristics of *** calculation model of the damping force of the composite buffer was *** low-speed impact test of the composite buffer was *** parameters of the buffer under low-speed impact were identified according to the model,and the nonlinear model of damping force was *** test results show that the composite buffer with EPMWM and viscous fluid can absorb the impact energy from the recoil movement effectively,and provide a new method for the buffer design of weapon equipment(such as artillery,mortar,etc.).

关键词： Entangled porous metallic wire materials Capillary property Viscousfluid Low-speed impact Damping force

Simplified liver imaging reporting and data system for the diagnosis of hepatocellular carcinoma on gadoxetic acid-enhanced magnetic resonance imaging

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2439-2448页

作者： rong Lyu Wei-Juan hu Di Wang jiao Wang Yu-Bing Ye Ke-Feng jia Department of Radiology Tianjin Third Central HospitalTianjin Key Laboratory of Extracorporeal Life Support for Critical DiseasesArtificial Cell Engineering Technology Research CenterTianjin 300170China

BACKGROUND The liver imaging reporting and data system(LI-RADS)diagnostic table has 15 cells and is too *** diagnostic performance of LI-RADS for hepatocellular carcinoma(HCC)is not satisfactory on gadoxetic acid-enhanced magnetic resonance imaging(EOB-MRI).AIM To evaluate the ability of the simplified LI-RADS(sLI-RADS)to diagnose HCC on *** A total of 331 patients with 356 hepatic observations were retrospectively *** diagnostic performance of sLI-RADS A-D using a single threshold was evaluated and compared with LI-RADS v2018 to determine the optimal *** algorithms of sLI-RADS A-D are as follows:The single threshold for sLI-RADS A and B was 10 mm,that is,classified observations≥10mm using an algorithm of 10-19 mm observations(sLI-RADS A)and≥20 mm observations(sLI-RADS B)in the diagnosis table of LI-RADS v2018,respectively,while the classification algorithm remained unchanged for observations0.999).With HBP hypointensity as an MF,the sensitivity of F-sLI-RADS was greater than that of LI-RADS v2018(93.0%vs 87.0%,P<0.001)and sLI-RADS D(93.0%vs 89.8%,P=0.016),without a lower specificity(86.5%vs 90.1%,P=0.062;86.5%vs 89.4%,P=0.125).Compared with that of LI-RADS v2018,the time to classif

关键词： Hepatocellular carcinoma Magnetic resonance imaging Liver Diagnosis Contrast agent

Shock-induced chemical reaction characteristics of PTFE-Al-Bi_(2)O_(3)reactive materials

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Defence Technology（防务技术） 2024年第6期36卷 1-12页

作者： Chunlan jiang rong hu Jingbo Zhang Zaicheng Wang Liang Mao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A ternary system of PTFE/Al/Bi_(2)O_(3)is constructed by incorporating PTFE-based reactive material and thermite for enhancing the energy release of the PTFE-based reactive *** effects of Bi_(2)O_(3)in the PTFE/Al/Bi_(2)O_(3)on both mechanical properties and the energy release were investigated through various tests such as thermogravimetry-differential scanning calorimetry,adiabatic oxygen bomb test and split Hopkinson pressure bar *** microstructure observed through scanning electron microscope and Xray diffraction results are used to analyze the ignition and reaction mechanism of PTFE/Al/Bi_(2)O_(3).The results indicate that the PTFE/Al/Bi_(2)O_(3)are capable of triggering the exothermic reaction of molten PTFE/Bi_(2)O_(3)and Al/Bi_(2)O_(3)over the PTFE/Al reactive materials,thereby promoting *** excessive aluminum in the ternary system is beneficial for increasing energy *** ignition of shock-induced chemical reactions in PTFE/Al/Bi_(2)O_(3)is closely related to the material *** dominant mechanism for hot-spot generation under Split Hopkinson Pressure Bar test is the frictional temperature rise at the microcrack after failure.

关键词： PTFE/Al/Bi_(2)O_(3) Shock-induced chemical reaction Energy release

Synergistic Interdecadal Evolution of Precipitation over Eastern China and the Pacific Decadal Oscillation during 1951-2015

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Advances in Atmospheric Sciences 2024年第1期41卷 53-72页

作者： Minmin WU rong-hua ZHANG Junya hu Hai ZHI Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Laosan Laboratory Qingdao 266237China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100029China

By using the multi-taper method(MTM)of singular value decomposition(SVD),this study investigates the interdecadal evolution(10-to 30-year cycle)of precipitation over eastern China from 1951 to 2015 and its relationship with the North Pacific sea surface temperature(SST).Two significant interdecadal signals,one with an 11-year cycle and the other with a 23-year cycle,are identified in both the precipitation and SST *** show that the North Pacific SST forcing modulates the precipitation distribution over China through the effects of the Pacific Decadal Oscillation(PDO)-related anomalous Aleutian low on the western Pacific subtropical high(WPSH)and Mongolia high(MH).During the development stage of the PDO cold phase associated with the 11-year cycle,a weakened WPSH and MH increased the precipitation over the Yangtze River Basin,whereas an intensified WPSH and MH caused the enhanced rain band to move northward to North China during the decay *** the development stage of the PDO cold phase associated with the 23-year cycle,a weakened WPSH and MH increased the precipitation over North China,whereas an intensified WPSH and the weakened MH increased the precipitation over South China during the decay *** 11-year and 23-year variabilities contribute differently to the precipitation variations in the different regions of China,as seen in the 1998flooding *** 11-year cycle mainly accounts for precipitation increases over the Yangtze River Basin,while the 23-year cycle is responsible for the precipitation increase over Northeast *** results have important implications for understanding how the PDO modulates the precipitation distribution over China,helping to improve interdecadal climate prediction.

关键词： MTM-SVD PDO SST anomalies interdecadal variability precipitation over China

Energy release characteristics of PTFE/Al/TiH2 reactive jet with different TiH2 content

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DEFENCE TECHNOLOGY 2024年第9期39卷 168-176页

作者： jiang, Chunlan Zhang, Jingbo hu, rong Mao, Liang Li, Ming Beijing Inst Technol State Key Lab Explos Sci & Technol Beijing 100081 Peoples R China

Titanium hydride (TiH2), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types of PTFE/Al/TiH2 reactive liners with different TiH2 content are prepared by the molding and sintering method. The energy release characteristics of PTFE/Al/TiH2 reactive jet are tested by the transient explosion energy test, and are characterized from pressure and temperature. The reaction delay time, pressure history, and temperature history of the energy release process are obtained, then the actual value of released energy and reaction efficiency of the reactive jet are calculated. The results show that the peak pressure and temperature of the PTFE/Al/TiH2 jet initially increase and then decrease with increasing TiH2 content. When the TiH2 content is 10%, the actual value of released energy and reaction efficiency increased by 24% and 6.4%, respectively, compared to the PTFE/Al jet. The reaction duration of the reactive material is significantly prolonged as the TiH2 content increased from 0% to 30%. Finally, combined with the energy release behaviors of PAT material and the dynamic deformation process of liner, the enhancement mechanism of TiH2 on energy release of the reactive jet is expounded. (c) 2024 China Ordnance Society. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： PTFE/Al/TiH2 Reactive materials Shaped charge Impact energy release characteristics TITANIUM