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Allometric models for aboveground biomass of six common subtropical shrubs and small trees

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Journal of Forestry Research 2022年第4期33卷 1317-1328页

作者： Cheng Huang Chun Feng Yuhua Ma Hua Liu Zhaocheng Wang shaobo Yang Wenjing Wang Songling Fu han Y.H.Chen College of Forestry and Landscape Architecture Anhui Agricultural University130 Changjiang West RoadHefei 230036AnhuiPeople’s Republic of China Faculty of Natural Resources Management Lakehead University955 Oliver RoadThunder BayON P7B 5E1Canada

The aboveground biomass(AGB)of shrubs and small trees is the main component for the productivity and carbon storage of understory vegetation in subtropical secondary ***,few allometric models exist to accurately evaluate understory *** estimate the AGB of five common shrub(diameter at base<5 cm,<5 m high)and one small tree species(<8 m high,trees’s seedling),206 individuals were harvested and species-specific and multi-species allometric models developed based on four predictors,height(H),stem diameter(D),crown area(Ca),and wood density(ρ).As expected,the six species possessed greater biomass in their stems compared with branches,with the lowest biomass in the ***-specific allometric models that employed stem diameter and the combined variables of D~2H andρDH as predictors accurately estimated the components and total AGB,with R^(2) values from 0.602 and 0.971.A multi-species shrub allometric model revealed that wood density×diameter×height(ρDH)was the best predictor,with R^(2) values ranging from between 0.81 and 0.89 for the components and total AGB,*** results indicated that height(H)and diameter(D)were effective predictors for the models to estimate the AGB of the six species,and the introduction of wood density(ρ)improved their *** optimal models selected in this study could be applied to estimate the biomass of shrubs and small trees in subtropical regions.

关键词： Aboveground biomass Allometric models Shrubs Small trees Subtropical forests

Comparative Study on Wire-Arc Additive Manufacturing and Conventional Casting of Al–Si Alloys:Porosity,Microstructure and Mechanical Property

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Acta Metallurgica Sinica(English Letters) 2022年第3期35卷 475-485页

作者： Yueling Guo Qifei han Jinlong Hu Xinghai Yang Pengcheng Mao Junsheng Wang shaobo Sun Zhi He Jiping Lu Changmeng Liu School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Center for Micro and Nano Technologies Beijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing hangxing Machinery Manufacturing Co. Ltd.Beijing 100013China

Here,we compare the porosity,microstructure and mechanical property of 4047 Al–Si alloys prepared by wire-arc additive manufacturing(WAAM)and conventional casting.X-ray microscopy reveals that WAAM causes a higher volume fraction of gas pores in comparison with conventional *** refi nements ofα-Al dendrites,eutectic Si particles and Ferich intermetallic compounds are achieved by WAAM,resulting from its rapid solidifi cation *** ultimate tensile strength(UTS,up to 205.6 MPa)and yield stress(YS,up to 98.0 MPa)are improved by WAAM at the expense of elongation after *** mechanical property anisotropy between scanning direction and build direction is minimal for alloys via *** microstructure refi nement and strength enhancement are enabled by increasing the travel speed of welding torch from 300 to 420 mm/min.

关键词： Wire-arc additive manufacturing Al–Si alloy Porosity Microstructure Strength

A method for determination of deuterium impurity in the helium beam

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Science China(Physics,Mechanics & Astronomy) 2018年第5期61卷 53-56页

作者： han Chen ShiWei Xu NingTao Zhang Jun Hu KuoAng Li shaobo Ma XiChao Ruan XiaoDong Tang LiYong Zhang Institute of Modern Physics Chinese Academy of Sciences Department of Nuclear Physics China Institute of Atomic Energy Joint Department for Nuclear Physics Lanzhou University and Institute of Modern Physics Chinese Academy of Sciences National Astronomical Observatories of China Chinese Academy of Sciences

Both the LUNA（Laboratory for Underground Nuclear Astrophysics）collaboration in Europe and the JUNA（Jinping Underground Laboratory for Nuclear Astrophysics）collaboration in China are planning to study the key react... 详细信息

关键词：氢杂质天体物理学横梁氦实验室结束期原子合作

Effects of topography and vegetation on distribution of rare earth elements in calcareous soils

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Acta Geochimica 2017年第3期36卷 469-473页

作者： Zhaoliang Song Yuntao Wu Xiaomin Yang Zijuan Xu Linan Liu Xiaodong Zhang Qian Hao shaobo Sun Guilin han Congqiang Liu Institute of the Surface-Earth System Science Research Tianjin University State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences School of Water Resources and Environment China University of Geosciences (Beijing) State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences

This study investigated the impact of topography and vegetation on distribution of rare earth elements(REEs)in calcareous soils using methods of single extraction and mass balance calculation. The purposes of the study were to set a basis for further research on the biogeochemical REE cycle and to provide references for soil–water conservation and REE-containing fertilizer amendments. The results show a generally flat Post-Archean Average Australian Shale—normalized REE pattern for the studied calcareous soils. REE enrichment varied widely. The proportion of acidsoluble phases of heavy REEs was higher than that of light REEs. From top to bottom of the studied hills, dominant REE sources transitioned from limestone in-situ weathering to input from REE-containing phases(e.g., clay minerals,amorphous iron, REE-containing fluids). Our results indicate that the REE content of calcareous soils is mainly controlled by slope aspect, while the enrichment degree of REEs is related to geomorphological position and vegetation ***, the proportion of acid-soluble phases of REEs is mainly controlled by geomorphological position.

关键词： REE distribution Weathering and pedogenesis Topography and vegetation Calcareous soils

Development of a 6D Kalman filter for charged particle tracking in time projection chamber without magnetic field

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Radiation Detection Technology and Methods 2020年第1期4卷 70-77页

作者： Qibin Zheng Jianjian Lu Yikai Huo Ke han Heng Lin Tao Li Kaixiang Ni shaobo Wang School of Medical Instrument and Food Engineering University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Laboratory for Particle Physics and Cosmology INPAC and Zhiyuan CollegeShanghai Jiao Tong UniversityShanghai 200240China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China SJTU-Paris Tech Elite Institute of Technology Shanghai Jiao Tong University800 Dongchuan Rd.Shanghai 200240China School of Physics Sun Yat-Sen UniversityGuangzhou 510275China

Background Track reconstruction is necessary for time projection chamber(TPC),because TPCs usually face the measure-ment error that impedes gaining precise spacial and angular *** Kalman filter is a well-performed and applicable algorithm to denoise and reconstruct the event *** In this paper,we develop a six-dimensional Kalman filter to reconstruct the particle track in high-energy physics experiments,while the most common form of Kalman filter used in many research fields is *** modelisation is based on a gaseous TPC,and the whole reconstruction process is first tested by a toy Monte Carlo *** The results show the Kalman filter can effectively reduce the noise and improve the detector ***,the performance of the Kalman filter is also verified with the data produced by the Geant4 toolkit.

关键词： Kalman filter TPC Track reconstruction Spatial resolution Angular resolution

知识创造过程效果的实证研究——个人和团队层面

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清华大学学报（自然科学版） 2006年第Z1期46卷 942-948页

作者：韩维贺季绍波大连理工大学管理学院大连116023 Sprott School of Business Carleton UniversityOttawaOntario K1S 5B6Canada

分析了中国情境下知识创造的4个维度与个人和团队中知识创造效果的关系,感知的知识管理有效性被作为衡量知识创造效果的标准。运用问卷调查的方法,通过对126个样本数据进行分析,发现:知识创造过程中的内化维度与个人层面上知识创造的效... 详细信息

分析了中国情境下知识创造的4个维度与个人和团队中知识创造效果的关系,感知的知识管理有效性被作为衡量知识创造效果的标准。运用问卷调查的方法,通过对126个样本数据进行分析,发现:知识创造过程中的内化维度与个人层面上知识创造的效果显著相关,会提高个人层面上感知的有效性;外化维度在个人层面上对知识创造的效果影响不显著;而外化、社会化和综合三个维度与团队中知识创造的效果显著相关,会提高团队层面上感知的有效性;个人层面上感知有效性会明显促进团队层面上感知有效性的提高。

关键词：知识管理知识创造 SECI模型

PTPRO represses colorectal cancer tumorigenesis and progression by reprogramming fatty acid metabolism

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Cancer Communications 2022年第9期42卷 848-867页

作者： Weixing Dai Wenqiang Xiang Lingyu han Zixu Yuan Renjie Wang Yanlei Ma Yongzhi Yang Sanjun Cai Ye Xu shaobo Mo Qingguo Li Guoxiang Cai Department of Colorectal Surgery Fudan University Shanghai Cancer CenterShanghai 200032P.R.China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032P.R.China Department of Surgery Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 528406P.R.China

Background:Abnormal expression of protein tyrosine phosphatases(PTPs)has been reported to be a crucial cause of *** a member of PTPs,protein tyrosine phosphatase receptor type O(PTPRO)has been revealed to play tumor suppressive roles in several cancers,while its roles in colorectal cancer(CRC)remains to be ***,we aimed to explore the roles and mechanisms of PTPRO in CRC initiation and ***:The influences of PTPRO on the growth and liver metastasis of CRC cells and the expression patterns of different lipid metabolism enzymes were evaluated in vitro and in *** and biological experiments were conducted to uncover the underpinning mechanisms of dysregulated de novo lipogenesis and fatty acidβ-***:PTPRO expression was notably downregulated in CRC liver metastasis compared to the primary cancer,and such a downregulation was associated with poor prognosis of patients with *** silencing significantly promoted cell growth and liver *** with PTPRO wild-type mice,PTPROknockout mice developed more tumors and harbored larger tumor loads under treatment with azoxymethane and dextran sulfate *** set enrichment analysis revealed that PTPRO downregulation was significantly associated with the fatty acid metabolism *** of fatty acid synthesis abrogated the effects of PTPRO silencing on cell growth and liver *** experiments indicated that PTPRO silencing induced the activation of the AKT serine/threonine kinase(AKT)/mammalian target of rapamycin(mTOR)signaling axis,thus promoting de novo lipogenesis by enhancing the expression of sterol regulatory element-binding protein 1(SREBP1)and its target lipogenic enzyme acetyl-CoA carboxylase alpha(ACC1)by activating the AKT/mTOR signaling ***,PTPRO attenuation decreased the fatty acid oxidation rate by repressing the expression of peroxisome proliferator-activated receptor alpha(PPARα)and its downstream enzyme

关键词： AKT colorectal cancer fatty acid oxidation fatty acid synthesis lipid metabolism liver metastasis mTOR PTPRO tumorigenesis

Preliminary study on the evaluation of Langerhans cell histiocytosis using F-18-fluoro-deoxy-glucose PET/CT

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Chinese Medical Journal 2014年第13期127卷 2458-2462页

作者： Zhou Wenlan Wu Hubing han Yanjiang Wang shaobo Dong Ye Wang Quanshi Nanfang PET Center Nanfang Hospital Southern MedicalUniversity Guangzhou Guangdong 510515 China Department of Radiology the First People's Hospital of YunnanProvince Kunming Yunnan 650032 China

Background Limited number of studies have been reported regarding the utilization of F-18-fluoro-deoxy-glucose （F-18-FDG） positron emission tomography/computed tomography （F-18-FDG PET/CT） in Langerhans cell histiocytosis （LCH）.The aim of this study was to assess the role of F-18-FDG PET/CT in the diagnosis and treatment of *** Eight newly diagnosed and seven recurrent patients with LCH received F-18-FDG PET/CT *** diagnosis of LCH was established by pathology,multi-modality imaging,and clinical *** F-18-FDG PET/CT was positive in 14 patients with 13 true positives and one false *** 45 LCH lesions were F-18-FDG avid including six small bone lesions ＜1.0 cm in *** mean maximal standardized uptake value （SUVmax） was 7.13±4.91.F-18-FDG uptake showed no significant difference between newly diagnosed lesions vs recurrent lesions （SUVmax：6.50±2.97 vs.7.93±6.60,t=-0.901,P=0.376）.Among 45 LCH lesions,68.9％（31/45） were found in bones and 31.1％（14/45） in soft *** most commonly involved bones were the pelvis and *** was no significant difference in F-18-FDG uptake between bone lesions ***-bone lesions （SUVmax：6.30±2.87 vs.8.97±7.58,t=1.277,P=0.221）.In two patients,changes in F-18-FDG uptake on serial PET/CT scans reflected response of lesions to *** The present study suggests that F-18-FDG PET/CT may be useful for diagnosis and assessing the treatment response of *** of the small sample size,further research is warranted to confirm our findings.

关键词： Langerhans cell histiocytosis diagnosis follow-up positron emission tomography computed tomography F-18-FDG

A gaseous time projection chamber with Micromegas readout for low-radioactive material screening

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Radiation Detection Technology and Methods 2023年第1期7卷 90-99页

作者： Haiyan Du Chengbo Du Ke han Shengming He Liqiang Liu Yue Meng shaobo Wang Tao Zhang Wenming Zhang Li Zhao Jifang Zhou Shanghai Laboratory for Particle Physics and Cosmology Key Laboratory for Particle Astrophysics and Cosmology(MOE)School of Physics and AstronomyINPACShanghai Jiao Tong UniversityShanghai200240China Yalong River Hydropower Development Company Chengdu610051China SPEIT(SJTU-ParisTech Elite Institute of Technology) Shanghai Jiao Tong UniversityShanghai200240China

Purpose Low-radioactive material screening is becoming essential for rare event search experiments,such as neutrinoless double beta decay and dark matter searches in underground laboratories.A gaseous time projection chamber(TPC)can be used for such purposes with large active areas and high *** A gaseous TPC with a Micromegas readout plane of approximately 20×20 cm^(2)is successfully constructed for surface alpha contamination *** We have characterized the energy resolution,gain stability,and tracking capability with calibration *** With the unique track-related background suppression cuts of the gaseous TPC,we have established that the alpha background rate of the TPC is(0.13±0.03)×10^(−6)Bq/cm^(2),comparable to the leading commercial solutions.

关键词： Low background Gaseous time projection chamber Background suppression