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Wood use and forest management by Neolithic millet farmers at the Xinglong site,northern China

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Science China Earth Sciences 2024年第6期67卷 1910-1921页

作者： hui SHEN Zhenwei QIU Keliang zhao Xinying ZHOU Xiaoqiang li Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China National Museum of China Beijing 100006China University of Chinese Academy of Sciences Beijing 100049China

The origin and development of agriculture and its relationship with climate change are hotly debated topics among environmental *** this study,we analyzed wood charcoal materials from the Neolithic Xinglong site in northern China in order to understand the woody vegetation around the site and how early millet farmers shaped local *** results suggest that the area around the Xinglong sites during 8700-7000 yr BP was primarily woodlands,including Prunus sibirica shrubs,Ulmus and Acer forests,and Populus stands near *** 8000 to 7000 yr BP,the warm and humid climate probably contributed to the expansion of Acer,Rhamnus,and Juniperus,and may have facilitated the development of early millet *** these ancient wood fragments that we studied,the high percent of Prunus charcoal appears to indicate an abundance of fruit trees,which might have constituted the main component of local ***,the wood taxa illustrate the existence of a variety of ecological habitats,and it is logical to assume that people made full use of the locally available wood ***,Populus and Ulmus were the dominant sources of *** results of tree-ring curvature analyses indicate that people mainly collected trunks or large branches of Ulmus,Populus,Acer,and Juniperus *** interpret the increasing use of Prunus twigs and the declining percentage of Prunus charcoal in the period between 8000-7000 yr BP as indicating that people started to protect and manage wild fruit *** may have started pruning to acquire more food resources as part of the cultural responses and adaptation strategies employed by these early millet cultivators.

关键词： Xinglong site Wood charcoal Wood use Woodland management

Regio-and Stereoselective Polymerization of Bio-based Ocimene by Rare-Earth Metal Catalysts

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Chinese Journal of Polymer Science 2024年第2期42卷 223-229,I0008页

作者： Qi-Yuan Wang li-Peng Sang Zhen Zhang Yang Jiang hui Tian Xia zhao Xiang Guo Shi-hui li State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechonologyXiangyang441003China Shanxi Coal Chemical Industry Technology Research Institute Xi’an710000China Hubei Institute of Aerospace Chemotechonology Xiangyang441003China

Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.

关键词： Biobased monomer Terpenes Ocimene Rare-earths Polymerization Regio/stereoselectivity Elastomer

Outcomes of chronic angle-closure glaucoma treated by phacoemulsification and endocyclophotocoagulation with or without endoscopically goniosynechialysis

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International Journal of Ophthalmology(English edition) 2022年第8期15卷 1273-1278页

作者： Xing Wu Ying Wang Xi liu zhao-hui li li-Qin Deng Dai-Shi Chen Da-Jiang Wang Senior Department of Ophthalmology the Third Medical Center of Chinese PLA General HospitalBeijing 100039China Department of Ophthalmology the First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Ophthalmology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China Shenzhen People’s Hospital the Second Clinical Medical College of Jinan Universitythe First Affiliate Hospital of Southern University of Science and TechnologyShenzhen 518020Guangdong ProvinceChina

AIM:To investigate the surgical outcomes of patients with chronic angle-closure glaucoma(CACG)treated with phacoemulsification(phaco)/endocyclophotocoagulation(ECP)with and without endoscopic goniosynechialysis(E-GSL).METHODS:A retrospective,nonrandomized,comparative case series was *** with CACG who underwent phaco in combination with either ECP alone(ECP group)or GSL with ECP(E-GSL group)from 2018 to 2019 were followed for 12mo and *** features and outcomes were identified and *** ECP and E-GSL groups were matched in age and baseline intraocular pressure(IOP).Changes in IOP,mean of visual acuity(VA),peripheral anterior synechiae(PAS)formation,and the number of glaucoma medications was ***:The ECP group included 32 eyes of 27 patients,and the E-GSL group included 32 eyes of 26 *** preoperative baseline IOP was 22.18±6.48 mm Hg in the ECP group and 22.95±6.71 mm Hg in the E-GSL group(P=0.644).The mean IOP reduction was 26.2%in the ECP group and 41.6%in the E-GSL group at *** mean postoperative VA(log MAR units)at 12mo was 0.47 in the ECP group and 0.36 in the E-GSL *** reduction in PAS formation and the number of glaucoma medications was also higher in the ECP group than E-GSL group at ***:The phaco/ECP and phaco/E-GSL groups both achieve a significant reduction in IOP without complications associated with traditional glaucoma filtration surgeries.

关键词： chronic angle-closure glaucoma endocyclophotocoagulation goniosynechialysis phacoemulsification

Single-cell transcriptomic atlas of goat ovarian aging

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Journal of Animal Science and Biotechnology 2024年第1期15卷 146-161页

作者： Dejun Xu Shuaifei Song Fuguo Wang Yawen li Ziyuan li hui Yao Yongju zhao Zhongquan zhao Chongqing Key Laboratory of Herbivore Science College of Animal Science and TechnologySouthwest UniversityChongqing 400715China

Background The ovaries are one of the first organs that undergo degenerative changes earlier in the aging process,and ovarian aging is shown by a decrease in the number and quality of ***,little is known about the molecular mechanisms of female age-related fertility decline in different types of ovarian cells during aging,especially in ***,the aim of this study was to reveal the mechanisms driving ovarian aging in goats at single-cell *** For the first time,we surveyed the single-cell transcriptomic landscape of over 27,000 ovarian cells from newborn,young and aging goats,and identified nine ovarian cell types with distinct gene-expression *** enrichment analysis showed that ovarian cell types were involved in their own unique biological processes,such as Wnt beta-catenin signalling was enriched in germ cells,whereas ovarian steroidogenesis was enriched in granulosa cells(GCs).Further analysis showed that ovarian aging was linked to GCs-specific changes in the antioxidant system,oxidative phosphorylation,and ***,we identified a series of dynamic genes,such as AMH,CRABP2,THBS1 and TIMP1,which determined the fate of ***,FOXO1,SOX4,and HIF1A were identified as significant regulons that instructed the differentiation of GCs in a distinct manner during ovarian *** This study revealed a comprehensive aging-associated transcriptomic atlas characterizing the cell typespecific mechanisms during ovarian aging at the single-cell level and offers new diagnostic biomarkers and potential therapeutic targets for age-related goat ovarian diseases.

关键词： Goat Granulosa cells Ovarian aging Single-cell transcriptomic

Investigation of stress distribution and damage behavior caused by forced installation of a composite bolted joint with a hole-location error

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Chinese Journal of Aeronautics 2024年第1期37卷 201-217页

作者： Chinan liU Yuan li Yi CHENG An’an zhao Kunpeng DU Yue SHI Ximing li hui CHENG School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China AVIC Xi’an Aircraft Industry Group Company LTD Xi’an 710089China

In this paper,the influence of forced installation caused by a hole-location error on the 3D stress distribution and damage of a composite bolted joint is *** analytical model of stress distributed on composite holes is promoted,in view of non-uniform extrusion caused by forced *** first,non-uniform extrusion of the hole edge caused by forced installation is *** to the contact state,expression of hole deformation is ***,based on Hertz theory,the maximum extrusion load is obtained with help of deformation *** constructing an elastic foundation beam model,3D stress distributed on a hole could be analyzed according to the extrusion ***,stress distribution predicted by the above analytical method is compared with that provided by FE considering composite ***,a forced installation experiment is carried out to analyze the damage distribution of the *** show that a central-symmetrically distributed stress is introduced by the hole-location *** an increment of the error,strength of composite decreases due to extrusion ***,stress presents a concave distribution on the *** the hole-location error exceeding 3%,stress decreases gradually due to failure of *** of holes does not exhibit a centrosymmetric *** damage is mainly distributed on the entrance of the hole at the lower sheet.

关键词： Hole-location error Composite joint Forced installation Stress distribution Damage

An improved deep dilated convolutional neural network for seismic facies interpretation

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Petroleum Science 2024年第3期21卷 1569-1583页

作者： Na-Xia Yang Guo-Fa li Ting-hui li Dong-Feng zhao Wei-Wei Gu State Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationChina University of Petroleum(Beijing)Beijing 102249China Dagang Branch Research InstituteBGPTianjin300280China

With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural *** intelligent and automated methods significantly reduce manual labor,particularly in the laborious task of manually labeling seismic ***,the extensive demand for training data imposes limitations on their wider *** overcome this challenge,we adopt the UNet architecture as the foundational network structure for seismic facies classification,which has demonstrated effective segmentation results even with small-sample training ***,we integrate spatial pyramid pooling and dilated convolution modules into the network architecture to enhance the perception of spatial information across a broader *** seismic facies classification test on the public data from the F3 block verifies the superior performance of our proposed improved network structure in delineating seismic facies *** analysis against the traditional UNet model reveals that our method achieves more accurate predictive classification results,as evidenced by various evaluation metrics for image ***,the classification accuracy reaches an impressive 96%.Furthermore,the results of seismic facies classification in the seismic slice dimension provide further confirmation of the superior performance of our proposed method,which accurately defines the range of different seismic *** approach holds significant potential for analyzing geological patterns and extracting valuable depositional information.

关键词： Seismic facies interpretation Dilated convolution Spatial pyramid pooling Internal feature maps Compound loss function

Accuracy of axial length measurements from immersion B-scan ultrasonography in highly myopic eyes

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International Journal of Ophthalmology(English edition) 2014年第3期7卷 441-445页

作者： Qing-Hua Yang Bing Chen Guang-Hua Peng zhao-hui li Yi-Fei Huang Department of Ophthalmology Chinese PLA General Hospital

AIM:To evaluate the accuracy of axial length(AL)measurements obtained from immersion B-scan ultrasonography(immersion B-scan)for intraocular lens(IOL)power calculation in patients with high myopia and ***:Immersion B-scan,contact A-scan ultrasonography(contact A-scan),and the IOLMaster were used to preoperatively measure the AL in 102 eyes from 102 patients who underwent phacoemulsification and IOL *** were divided into two groups according to the AL:one containing patients with22 mm≤AL<26 mm(group A)and the other containing patients with AL≥26 mm(group B).The mean error(ME)was calculated from the difference between the AL measurement methods predicted refractive error and the actual postoperative refractive ***:Ingroup A,ALs measured byimmersion Bscan(23.48±1.15)didn’t differ significantly from those measured by the IOLMaster(23.52±1.17)or from those by contact A-scan(23.38±1.20).In the same group,the standard deviation(SD)of the mean error(ME)of immersion B-scan(-0.090±0.397 D)didn’t differ significantly from those of IOLMaster(-0.095±0.411 D)and contact A-scan(-0.099±0.425 D).In group B,ALs measured by immersion B-scan(27.97±2.21 mm)didn’t differ significantly from those of the IOLMaster(27.86±2.18 mm),but longer than those measured by Contact A-scan(27.75±2.23 mm,P=0.009).In the same group,the standard deviation(SD)of the mean error(ME)of immersion B-scan(-0.635±0.157 D)didn’t differ significantly from those of the IOLMaster(-0.679±0.359 D),but differed significantly from those of contact A-scan(-0.953±1.713 D,P=0.028).CONCLUSION:ImmersionB-scanexhibitsmeasurement accuracy comparable to that of the IOLMaster,and is thus a good alternative in measuring AL in eyes with high myopia when the IOLMaster can’t be used,and it is more accurate than the contact A-scan.

关键词： axial length measurement immersion ultrasonography high myopia

Review Article li-current collector interface in lithium metal batteries

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Nano Research 2024年第10期17卷 8706-8728页

作者： Tian-Yu Wang Dingyi zhao Keyue liang Yuzhang li Department of Chemical and Biomolecular Engineering University of CaliforniaLos AngelesLos AngelesCalifornia 90095USA

Interfaces within batteries,such as the widely studied solid electrolyte interface(SEI),profoundly influence battery *** these interfaces,the solid-solid interface between electrode materials and current collectors is crucial to battery performance but has received less discussion and *** review highlights the latest research advancements on the solid-solid interface between lithium metal(the next-generation anode)and current collectors(typically copper),focusing on factors affecting the li-current collector interface and improvement strategies from perspectives of current collector substrate(lithiophilicity,crystal facets,mechanical properties,and topological structure),electrolyte chemistry,current density,stacking pressure,SEI,electric field and temperature,and provides a future directions and opportunities on this topic.

关键词： lithium metal anode current collectors li-current collector interface solid-solid interface improvement strategies

Optical and electrical anisotropy regulation engineering of low-dimensional materials toward polarized detection and imaging applications

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Rare Metals 2024年第7期43卷 2968-2993页

作者： Jian-Bin Zhang Nan Zhou li-hui Zhang Cong-hui Shang Jia-Xuan li Yi zhao Guo-hui Jia Ru-Sen Yang Hua Xu Xiao-Bo li Shaanxi Joint Key Laboratory of Graphene Shaanxi Key Laboratory of High-Orbits-Electron Materials and Protection Technology for AerospaceShaanxi Joint Key Laboratory of GrapheneSchool of Advanced Materials and NanotechnologyXidian UniversityXi'an710126China Guangzhou Institute of Technology Xidian UniversityGuangzhou 710068China Xi'an Thermal Power Research Institute Co. LtdXi'an 710054China Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an Xi'an 710119China

Polarized-sensitive image sensors are a kind of photodetector with great development potential due to their enhanced ability to detect and identify the target objects from the aspect of spatial,spectral and polarized ***,low-dimensional anisotropic materials with inherent anisotropic properties,ultrathin thickness,tunable bandgap and feasible integration with complementary metal oxide semiconductor(CMOS)fabrication processes have attracted great interest for their facilitation of polarized photodetector devices *** the polarized detection performance of low-dimensional materials to satisfy realistic needs stimulates the exploration of modulation of anisotropic *** this review,we comprehensively introduce the latest research progress in modulating the optical and optoelectronic anisotropy characteristics of low-dimensional *** strategy of anisotropy regulation through crystal structure engineering and coupling system is discussed ***,the latest progress in image recognition applications using anisotropic low-dimensional materials is reviewed in ***,we summarize the challenge and propose future opportunities in the practical application of polarized-sensitive imaging photodetectors based on low-dimensional anisotropic materials.

关键词： Anisotropy Polarized detection Image recognition Low-dimensional materials