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| 1 | PI3K/Akt signaling transduction pathway is involved in rat vascular smooth muscle cell proliferation induced by apelin-13显示文摘脉管的光滑的肌肉房间(VSMC ) 被将生物的活组织移植于培养基中培养方法从男 SpragueDawley 老鼠的胸的主动脉准备经由 3 kinase (PI3K )/Akt 发信号 transduction 小径由 apelin-13 导致了的 phosphoinositide 观察 VSMC 增长。PI3K, phospho-PI3K, phospho-Akt, ERK1/2, phospho-ERK1/2 和 cyclin D1 的表示被西方的污点分析检测。结果证明 apelin-13 在剂量依赖者和时间依赖者举止支持了 phospho-PI3K 和 phospho-Akt 的表示。PI3K 禁止者 LY294002 显著地减少了 phospho-PI3K, phospho-Akt, phospho-ERK1/2,和 cyclin D1 的表示由 apelin-13 导致了。Akt 禁止者 1701-1 显著地减少了 phospho-Akt, phospho-ERK1/2,和 cyclin D1 的表示由 apelin-13 刺激了。MTT 试金结果证明 PI3K 禁止者 LY294002 和 Akt 禁止者 1701-1 显著地禁止了 apelin-13 导致的 VSMC 增长。Apelin-13 通过表明 transduction 小径的 PI3K/Akt 支持了 VSMC 增长。 | Changhui Liu Tao Su Fang Li Lanfang Li Xuping Qin Weinan Pan Fen Feng Feng Chen Duanfang Liao Linxi Chen | 2010 | Acta Biochimica et Biophysica Sinica2010，42，6： | 41 |
| 2 | Selective laser melting of NiTi alloy with superior tensile property and shape memory effect显示文摘It is a challenge to develop complex-shaped Ni Ti shape memory alloy parts by traditional processing methods, due to the poor machinability of Ni Ti alloy. It is reported that selective laser melting(SLM) of additive manufacturing could overcome this problem. However, the reported SLM-produced Ni Ti exhibits poor tensile ductility due to the inner defects and adverse unidirectional columnar grains from SLM process. In this work, the defect-less SLM-Ni Ti with nondirective columnar grains was fabricated by optimizing the intraformational laser scanning length and interformational laser scanning direction. The obtained lath-shaped SLM-Ni Ti sample exhibits tensile strain of 15.6%, more than twice of the reported maximum result(7%). Besides, the SLM-Ni Ti part with complex geometry displays a shape memory recovery of 99% under compressive deformation of 50%. | Zhiwei Xiong Zhonghan Li Zhen Sun Shijie Hao Ying Yang Meng Li Changhui Song Ping Qiu Lishan Cui | 2019 | Journal of Materials Science & Technology2019，35，10： | 15 |
| 3 | Gold nanoflowers for 3D volumetric molecular imaging of tumors by photoacoustic tomography显示文摘By binding molecular probes that target tumor cells, gold nanoparticles (AuNPs) with superior characteristics have shown great potential in tumor molecular imaging studies. The non-invasive, high-resolution, and three-dimensional imaging of the targeted AuNPs within the tumor is desirable for both diagnosis and therapy. In this study, gold nanoflowers (AuNFs) are presented as a novel contrast agent for photoacoustic tomography (PAT). By binding to folic acid, the molecular probe, the tail-vein injected AuNFs concentrated within the tumor site in mice; this was clearly visualized by three-dimensional (3D) PAT imaging. In addition, toxicity assay proved that AuNFs were harmless to living cells and animals. Our results demonstrate that AuNFs have great potential in tumor molecular imaging. | Yuanyuan Jiang Zijian Deng Dan Yang Xin Deng Qi Li Yinlin Sha Changhui Li Dongsheng Xu | 2015 | Nano Research2015，8，7： | 8 |
| 4 | First light of the 1.8-m solar telescope–CLST显示文摘Large-aperture solar telescopes play an important role in solar observations and research,and require high temporal and spatial resolution[1].To solve some fundamental problems such as the solar dynamo,coronal heating,and the triggering of major solar eruptions,the spatial resolution for solar-atmosphere observation should reach at least 0.1 arcsec[2]. | ChangHui Rao NaiTing Gu XueJun Rao Cheng Li LanQiang Zhang JinLong Huang Lin Kong Ming Zhang YunTao Cheng Yi Pu Hua Bao YouMing Guo YangYi Liu JinSheng Yang LiBo Zhong ChangJun Wang Kai Fang XiaoJun Zhang DongHong Chen Cheng Wang XinLong Fan ZhiWu Yan KeLe Chen XiYa Wei Lei Zhu Hong Liu YongJian Wan Hao Xian WenLi Ma | 2020 | Science China(Physics,Mechanics & Astronomy)2020，63，10： | 6 |
| 5 | Flexible control strategy for HVDC transmission system adapted to intermittent new energy delivery显示文摘Intermittent new energy delivery requires increasing the flexibility of ultra-high voltage direct current(DC)power adjustment.Based on a converter steady-state model and a DC power model,the control angle constraints of a converter valve are relaxed for power regulation.In this paper,a flexible DC power control method based on a fixed tap changer position is proposed.The initial ratio of the converter transformer is optimized.The effects of the fixed-tap changer position control on the control angle,reactive power compensation,and commutation failure are analyzed.The new control method allows a DC system to operate at a large angle and increase the additional reactive power loss while improving the commutation security margin.Steady-state and electromagnetic transient simulations in the CIGRE test system verify the validity of the method proposed in this paper and the correctness of the analysis conclusions. | Chenhao Li Kuan Li Changhui Ma Pengfei Zhang Qi Tao Yingtao Sun Xin Wang | 2021 | Global Energy Interconnection2021，4，4： | 6 |
| 6 | A novel artificial nerve graft for repairing longdistance sciatic nerve defects:a self-assembling peptide nanofiber scaffold-containing poly (lactic-co-glycolic acid) conduit显示文摘In this study, we developed a novel artificial nerve graft termed self-assembling peptide nanofiber scaffold(SAPNS)-containing poly(lactic-co-glycolic acid)(PLGA) conduit(SPC) and used it to bridge a 10-mm-long sciatic nerve defect in the rat. Retrograde tracing, behavioral testing and histomorphometric analyses showed that compared with the empty PLGA conduit implantation group, the SPC implantation group had a larger number of growing and extending axons, a markedly increased diameter of regenerated axons and a greater thickness of the myelin sheath in the conduit. Furthermore, there was an increase in the size of the neuromuscular junction and myofiber diameter in the target muscle. These findings suggest that the novel artificial SPC nerve graft can promote axonal regeneration and remyelination in the transected peripheral nerve and can be used for repairing peripheral nerve injury. | Xianghai Wang Mengjie Pan Jinkun Wen Yinjuan Tang Audra D.Hamilton Yuanyuan Li Changhui Qian Zhongying Liu Wutian Wu Jiasong Guo | 2014 | Neural Regeneration Research2014，9，24： | 5 |
| 7 | High-yield preparation of robust gold nanoshells on silica nanorattles with good biocompatiblity显示文摘Although gold nanoshells are widely considered as one of the promising photothermal nanomaterials used for biomedicine, the high cost, low yield and poor stability severely limit their potential application in clinical trials.Herein, robust gold nanoshells on silica nanorattles(GSNs)were easily prepared in a high yield by an improved seedmediated method employing polyvinylpyrrolidone(PVP) as a stabilizing and capping agent. The present method is very simple, effective and reproducible and can well control the growth process of gold nanoshells. The as-prepared GSNs have a narrow size distribution(<10 % in standard deviation). Furthermore, the utilization rate of Au in the solution used for the growth of gold nanoshells increases by 70 %than that in previous method. The resultant GSNs have a good structural stability after placing over 6 months due to the protection of PVP. More importantly, in vivo and in vitro toxic studies indicate that the GSNs have good biocompatibility. We believe that our preparation method will remarkably promote the use of gold nanoshells for biomedicine. | Changhui Fu Chaofeng He Longfei Tan Shunhao Wang Lu Shang Linlin Li Xianwei Meng Huiyu Liu | 2016 | Science Bulletin2016，61，4： | 5 |
| 8 | Selective hydrogenolysis of 5-hydroxymethylfurfural to 2,5-dimethylfuran over Co_3O_4 catalyst by controlled reduction显示文摘2,5-dimethyfuran(DMF), which is produced from 5-hydroxymethyfurfural(HMF) by hydrodeoxygenation(HDO), is a high quality fuel due to the high heating value, the high octane number and the suitable boiling point. Selective hydrogenation of HMF into liquid fuel DMF has been widely researched. In this paper, Co_3O_4 catalyst was prepared by co-precipitation and was reduced at different temperatures to form Co–CoO_x catalysts. The characterization of catalysts was tested by XRD, TEM, XPS, TPR, BET and NH3-TPD.Co–CoO_x possessed a high amount of Co metal and CoO_x acidic sites, wherein Co worked as the active hydrogenation sites and CoO_x acted as the acid promoter to facilitate the selective HDO of HMF to DMF.The synergistic effect of Co–CoO_x is the key for HDO of HMF, obtaining 83.3% of DMF yield at 170 °C, 12 h and the reduction temperature of 400 °C. This method not only saves the catalyst cost, but also promotes the utilization of biomass energy. | Dan Li Qiying Liu Changhui Zhu Haiyong Wang Chunhua Cui Chenguang Wang Longlong Ma | 2019 | Journal of Energy Chemistry2019，28，3： | 4 |
| 9 | Human amnion tissue injected with human umbilical cord mesenchymal stem cells repairs damaged sciatic nerves in rats显示文摘Human umbilical cord mesenchymal stem cells,incorporated into an amnion carrier tubes,were assessed for nerve regeneration potential in a rat nerve defect model.Damaged nerves were exposed to human amnion carriers containing either human umbilical cord mesenchymal stem cell (cell transplantation group)or saline(control group).At 8,12,16 and 20 weeks after cell implantation,the sciatic functional index was higher in the cell transplantation group compared with the control group.Furthermore,electrophysiological examination showed that threshold stimulus and maximum stimulus intensity gradually decreased while compound action potential amplitude gradually increased.Hematoxylin-eosin staining showed that regenerating nerve fibers were arranged in nerve tracts in the cell transplantation group and connective tissue between nerve tracts and amnion tissue reduced over time.Gastrocnemius muscle cell diameter,wet weight and restoration ratio were increased.These data indicate that transplanted human umbilical cord mesenchymal stem cells,using the amnion tube connection method,promote restoration of damaged sciatic nerves in rats. | Dehua Li Changhui Wang Wei Shan Ruixia Zeng Yan Fang Pan Wang | 2012 | Neural Regeneration Research2012，7，23： | 4 |
| 10 | Flexible Si/PEDOT:PSS hybrid solar cells显示文摘因为他们的低生产费用和高效, Si 混合太阳能电池在最近的年里吸引了巨大的研究注意。然而,灵活 Si 混合太阳能电池很少由于与好灵活性制作单人赛水晶的 Si 的困难被报导了。在这研究,我们制作了灵活 Si/PEDOT : 有用一条灵巧的途径的 micro-pyramid-structured Si 轻吸收器的 PSS 混合太阳能电池。与有 4% 的力量变换效率的平面灵活混合太阳能电池相比,有 micro-pyramid-structured Si 轻吸收器的太阳能电池有 6.3% 的更高的效率。外部量效率和电气化学的阻抗光谱学大小表明有 micro-pyramid-structured Si 轻吸收器的太阳能电池在 4001,000 nm 的系列区域展出了显著轻收获的改进并且与平面房间相比有一个更小的系列电阻和更大的再结合抵抗,产出更高的效率。在机械弯曲的测试,另外,有 micro-pyramid-structured Si 轻吸收器的灵活太阳能电池在为 600 个周期弯曲以后展出了优秀表演稳定性。我们的调查结果为灵活 Si/PEDOT 的真实世界的应用程序打了基础: 在下一代的便携式的电子学的 PSS 混合太阳能电池。 | Shuxin Li Zhibin Pei Fei Zhou Ying Liu Haibo Hu Shulin Ji Changhui Ye | 2015 | Nano Research2015，8，10： | 3 |
| 11 | An encapsulated optical microsphere sensor for ultrasound detection and photoacoustic imaging显示文摘Optical whispering-gallery microresonators have attracted considerable interest for ultrasensitive ultrasound detection and photoacoustic imaging because of the combination of high quality factors and small cavity sizes.In the last decade,ultrasonic sensors with on-chip microcavities have been extensively developed;however,they are unsuitable for the near-field photoacoustic microscopy of micro/nanoscale objects in complex biological environments and endoscopic imaging.In this work,we developed ultrasonic sensors using two types of encapsulated microsphere resonators with different cavity materials.A noise equivalent pressure of as low as 160 Pa at 20 MHz was achieved with the acoustic response up to 70 MHz at-6 d B.Furthermore,the microsensor was used for photoacoustic microscopy in which we successfully performed 3 D imaging of hairs and leaf veins.The microsphere ultrasonic sensor has considerable potential as a probe-type ultrasonic detector for near-field photoacoustic microscopy of micro/nanoscale objects such as subcellular structures and high-resolution endoscopic photoacoustic imaging with its high sensitivity and wide bandwidth. | Jialve Sun Jia-Wei Meng Shui-Jing Tang Changhui Li | 2022 | Science China(Physics,Mechanics & Astronomy)2022，65，2： | 3 |
| 12 | Molecular analysis of rice plants harboring a multi-functional T-DNA tagging system显示文摘About 25,000 rice T-DNA insertional mutant lines were generated using the vector pCAS04 which has both promoter-trapping and activation-tagging function. Southern blot analysis revealed that about 40% of these mutants were single copy integration and the average T-DNA insertion number was 2.28. By extensive phenotyping in the field, quite a number of agronomically important mutants were obtained. Histochemical GUS assay with 4,310 primary mutants revealed that the GUS-staining frequency was higher than that of the previous reports in various tissues and especially high in flowers. The T-DNA flanking sequences of some mutants were isolated and the T-DNA insertion sites were mapped to the rice genome. The flanking sequence analysis demonstrated the different integration pattern of the right border and left border into rice genome. Compared with Arabidopsis and poplar, it is much varied in the T-DNA border junctions in rice. | Yimian Ma Luo Liu Chengguang Zhu Changhui Sun Bo Xu Jun Fang Jiuyou Tang Anding Luo Shouyun Cao Gupo Li Qian Qian Yongbiao Xue Chengcai Chu | 2009 | Journal of Genetics and Genomics2009，36，5： | 3 |
| 13 | Solvent-and metal-directed lanthanide-organic frameworks based on pamoic acid:observation of slow magnetization relaxation,magnetocaloric effect and luminescent sensing显示文摘Two types of lanthanide coordination polymers, namely, [Ln(PA)(NO_3)(DMA)_3]_n(Ln=Gd(1), Dy(2), Eu(3), Tb(4))(type I), and {[Ln_2(PA)_3(DMF)_4]·2DMF}(Ln=Eu(5), Tb(6))(type II)(PA=Pamoic acid, DMA=dimethylacetamide,DMF=N,N-dimethylformamide), have been synthesized by the reaction of Ln(NO_3)_3·6H_2O with pamoic acid through layer diffusion method. These complexes were characterized by single crystal X-ray diffraction, infrared spectroscopy(IR),thermogravimetric analysis(TGA), fluorescence and magnetic measurements. Solvents and lanthanide atoms in the reaction play an important role in controlling different structures. Type I demonstrated 1-D linear chain structure connected by Ln atoms and PA ligands. Type II exhibited non-interpenetrating 3-D 6-connected 4_36^(12) nets based on binuclear [Ln_2(CO_2)_6(DMF)_4] cores.Magnetic properties of complexes 1–4 were investigated in details. Complex 1 shows significant magnetocaloric effect with–ΔS_m=20.37 J kg^(–1) K^(–1) at 3.0 K and 7 T. Complex 2 exhibits slow relaxation of the magnetization. Complexes 3–6 exhibit both ligand- and metal-centered fluorescent properties. Complex 6 demonstrates fluorescent sensing of DMF and Cu^(2+) ion. | Suna Wang Ranran Ma Zhiwei Chen Yunwu Li Tingting Cao Changhui Zhou Junfeng Bai | 2016 | Science China Chemistry2016，59，8： | 3 |
| 14 | EAST-Educational Adaptive-optics Solar Telescope显示文摘For the public having a better understanding of solar activities,the Educational Adaptive-optics Solar Telescope(EAST)was built in July 2021 and is located at the Shanghai Astronomy Museum.The EAST consists of a 65 cm aperture solar telescope with a 177-element adaptive optics system and two-channel high resolution imaging system at the Hαand TiO bands,in addition to three full disk solar telescopes at CaK,Hαand TiO bands equipped on the tube of the main telescope.In this paper,the configuration of the EAST is described.Its performance and on-sky observational results are presented.The EAST,to our knowledge,is the most advanced solar telescope for the popularization of science in the world.Due to its excellent performance,the data acquired by the EAST can also be used for research on solar physics and space weather prediction. | Changhui Rao Xuejun Rao Zhimao Du Hua Bao Cheng Li Jinlong Huang Youming Guo Libo Zhong Qing Lin Xin Ge Jinsheng Yang Xinlong Fan Yangyi Liu Dan Jia Xin Li Mei Li Ming Zhang Yuntao Cheng Jiahui Zhou Jiawen Yao Lanqiang Zhang Naiting Gu | 2022 | Research in Astronomy and Astrophysics2022，22，6： | 3 |
| 15 | Advances and challenges on springback control for creep age forming of aluminum alloy显示文摘Creep age forming(CAF)is an advanced forming technology that combines creep deformation and age hardening processes.When compared with the conventional forming technologies including roll bending and shot-peen forming,CAF has many advantages of low residual stress,excellent dimensional stability,good service performance and short production cycle.It is an optimal technique for precise manufacturing for shape and properties of large-scale complicated thinwalled components of light-weight and high strength aluminum alloys in the aviation and aerospace industries.Nevertheless,CAF has an inevitable disadvantage that a large amount of springback occurs after unloading,which brings a challenge on the accurate shape forming and property tailoring of components.Therefore,how to achieve accurate prediction and control of springback has always been a bottleneck hindering the development of CAF to more industrial applications.After the factors of affecting springback and measures of reducing springback are summarized from the internal and external aspects,constitutive models for predicting springback and springback compensation methods for CAF of aluminum alloy panel components are reviewed.Then,a review of research progresses on tool design for CAF is presented.Finally,in view of the key issue that it is difficult to predict and control the shape and properties of components during CAF,the technical challenges are discussed and future development trends of CAF are prospected. | Liwen ZHANG Heng LI Tianjun BIAN Changhui WU Yang GAO Chao LEI | 2022 | Chinese Journal of Aeronautics2022，35，10： | 3 |
| 16 | Integrating global socio-economic influences into a regional land use change model for China显示文摘与快速的经济开发和都市化,在中国的陆地使用在最近的年里经历了巨大的变化;并且这以后将可能继续。在中国的陆地使用问题是迫切的并且需要推进学习。快速的陆地使用变化和经济开发为综合陆地使用变化研究使中国成为一个理想的区域,特别地多重因素的考试和在全球经济集成的上下文的全球地区性的相互作用。这份报纸论述一条综合建模途径在使用在地区性的规模改变的土地上检验全球社会经济的过程的影响。我们由联合一个简单全球社会经济的模型(GLOBFOOD ) 和地区性的空间分配模型(线索) 开发一个综合模型系统。模型系统用一个应用程序被说明在中国打使用。为一个给定的气候变化,人口生长,和各种各样的社会经济的状况,一个全球社会经济的模型在陆地使用上模仿全球市场和经济的影响,并且确定不同土地的变化使用类型。空间分发模型决定的陆地使用在由采用一个加权的适用性索引的每个空间格子很适当的陆地使用的类型,源于生态系统国家和地点条件的专家知识。一系列模型模拟将被进行并且分析了表明综合模型的能力与使用在中国改变的地区性的土地连接全球社会经济的因素。结果在中国允许陆地使用和风景的未来动力学的探索[出版摘要] | Xia XU Qiong GAO Changhui PENG Xuefeng CUI Yinghui LIU Li JIANG | 2014 | Frontiers of Earth Science2014，8，1： | 2 |
| 17 | Management scheme influence and nitrogen addition effects on soil CO_(2),CH_(4),and N_(2)O fluxes in a Moso bamboo plantation显示文摘Background:It is still not clear whether the effects of N deposition on soil greenhouse gas(GHG)emissions are influenced by plantation management schemes.A field experiment was conducted to investigate the effects of conventional management(CM)versus intensive management(IM),in combination with simulated N deposition levels of control(ambient N deposition),30 kg N·ha^(−1)·year^(−1)(N30,ambient+30 kg N·ha^(−1)·year^(−1)),60 kg N·ha^(−1)·year^(−1)(N60,ambient+60 kg N·ha^(−1)·year^(−1)),or 90 kg N·ha^(−1)·year^(−1)(N90,ambient+90 kg N·ha^(−1)·year^(−1))on soil CO_(2),CH_(4),and N_(2)O fluxes.For this,24 plots were set up in a Moso bamboo(Phyllostachys edulis)plantation from January 2013 to December 2015.Gas samples were collected monthly from January 2015 to December 2015.Results:Compared with CM,IM significantly increased soil CO_(2) emissions and their temperature sensitivity(Q_(10))but had no significant effects on soil CH_(4) uptake or N_(2)O emissions.In the CM plots,N30 and N60 significantly increased soil CO_(2) emissions,while N60 and N90 significantly increased soil N_(2)O emissions.In the IM plots,N30 and N60 significantly increased soil CO_(2) and N_(2)O emissions,while N60 and N90 significantly decreased soil CH_(4) uptake.Overall,in both CM and IM plots,N30 and N60 significantly increased global warming potentials,whereas N90 did not significantly affect global warming potential.However,N addition significantly decreased the Q_(10) value of soil CO_(2) emissions under IM but not under CM.Soil microbial biomass carbon was significantly and positively correlated with soil CO_(2) and N_(2)O emissions but significantly and negatively correlated with soil CH_(4) uptake.Conclusion:Our results indicate that management scheme effects should be considered when assessing the effect of atmospheric N deposition on GHG emissions in bamboo plantations. | Junbo Zhang Quan Li Jianhua Lv Changhui Peng Zhikang Gu Lianghua Qi Xuzhong Song Xinzhang Song | 2021 | Forest Ecosystems2021，8，1： | 2 |
| 18 | Biochar amendments increase soil organic carbon storage and decrease global warming potentials of soil CH4 and N2O under N addition in a subtropical Moso bamboo plantation显示文摘Background: Nitrogen(N) deposition affects soil greenhouse gas(GHG) emissions, while biochar application reduces GHG emissions in agricultural soils. However, it remains unclear whether biochar amendment can alleviate the promoting effects of N input on GHG emissions in forest soils. Here, we quantify the separate and combined effects of biochar amendment(0, 20, and 40 t·ha) and N addition(0, 30, 60, and 90 kg N·ha·yr) on soil GHG fluxes in a long-term field experiment at a Moso bamboo(Phyllostachys edulis) plantation.Results: Low and moderate N inputs(≤60 kg N·ha·yr) significantly increase mean annual soil carbon dioxide(CO) and nitrous oxide(NO) emissions by 17.0%–25.4% and 29.8%–31.2%, respectively, while decreasing methane(CH) uptake by 12.4%–15.9%, leading to increases in the global warming potential(GWP) of soil CHand NO fluxes by 32.4%–44.0%. Moreover, N addition reduces soil organic carbon(C;SOC) storage by 0.2%–6.5%. Compared to the control treatment, biochar amendment increases mean annual soil CO2emissions, CHuptake, and SOC storage by 18.4%–25.4%, 7.6%–15.8%, and 7.1%–13.4%, respectively, while decreasing NO emissions by 17.6%–19.2%, leading to a GWP decrease of 18.4%–21.4%. Biochar amendments significantly enhance the promoting effects of N addition on soil COemissions, while substantially offsetting the promotion of N2O emissions, inhibition of CHuptake, and decreased SOC storage, resulting in a GWP decrease of 9.1%–30.3%.Additionally, soil COand CHfluxes are significantly and positively correlated with soil microbial biomass C(MBC) and pH. Meanwhile, NO emissions have a significant and positive correlation with soil MBC and a negative correlation with pH.Conclusions: Biochar amendment can increase SOC storage and offset the enhanced GWP mediated by elevated N deposition and is, thus, a potential strategy for increasing soil C sinks and decreasing GWPs of soil CHand NO under increasing atmospheric N deposition in Moso bamboo plantations. | Quan Li Kunkai Cui Jianhua Lv Junbo Zhang Changhui Peng Yongfu Li Zhikang Gu Xinzhang Song | 2022 | Forest Ecosystems2022，9，4： | 2 |
| 19 | Strong controls of daily minimum temperature on the autumn photosynthetic phenology of subtropical vegetation in China显示文摘Background:Vegetation phenology research has largely focused on temperate deciduous forests,thus limiting our understanding of the response of evergreen vegetation to climate change in tropical and subtropical regions.Results:Using satellite solar-induced chlorophyll fluorescence(SIF)and MODIS enhanced vegetation index(EVI)data,we applied two methods to evaluate temporal and spatial patterns of the end of the growing season(EGS)in subtropical vegetation in China,and analyze the dependence of EGS on preseason maximum and minimum temperatures as well as cumulative precipitation.Our results indicated that the averaged EGS derived from the SIF and EVI based on the two methods(dynamic threshold method and derivative method)was later than that derived from gross primary productivity(GPP)based on the eddy covariance technique,and the time-lag for EGSsif and EGSevi was approximately 2 weeks and 4 weeks,respectively.We found that EGS was positively correlated with preseason minimum temperature and cumulative precipitation(accounting for more than 73%and 62%of the study areas,respectively),but negatively correlated with preseason maximum temperature(accounting for more than 59%of the study areas).In addition,EGS was more sensitive to the changes in the preseason minimum temperature than to other climatic factors,and an increase in the preseason minimum temperature significantly delayed the EGS in evergreen forests,shrub and grassland.Conclusions:Our results indicated that the SIF outperformed traditional vegetation indices in capturing the autumn photosynthetic phenology of evergreen forest in the subtropical region of China.We found that minimum temperature plays a significant role in determining autumn photosynthetic phenology in the study region.These findings contribute to improving our understanding of the response of the EGS to climate change in subtropical vegetation of China,and provide a new perspective for accurately evaluating the role played by evergreen vegetation in the regional carbon budget. | Peixin Ren Zelin Liu Xiaolu Zhou Changhui Peng Jingfeng Xiao Songhan Wang Xing Li Peng Li | 2021 | Forest Ecosystems2021，8，3： | 2 |
| 20 | A practical method utilizing multi-spectral LiDAR to aid points cloud matching in SLAM显示文摘Light Detection and Ranging(LiDAR)sensors are popular in Simultaneous Localization and Mapping(SLAM)owing to their capability of obtaining ranging information actively.Researchers have attempted to use the intensity information that accompanies each range measurement to enhance LiDAR SLAM positioning accuracy.However,before employing LiDAR intensities in SLAM,a calibration operation is usually carried out so that the intensity is independent of the incident angle and range.The range is determined from the laser beam transmitting time.Therefore,the key to using LiDAR intensities in SLAM is to obtain the incident angle between the laser beam and target surface.In a complex environment,it is difficult to obtain the incident angle robustly.This procedure also complicates the data processing in SLAM and as a result,further application of the LiDAR intensity in SLAM is hampered.Motivated by this problem,in the present study,we propose a Hyperspectral LiDAR(HSL)-based-intensity calibration-free method to aid point cloud matching in SLAM.HSL employed in this study can obtain an eight-channel range accompanied by corresponding intensity measurements.Owing to the design of the laser,the eight-channel range and intensity were collected with the same incident angle and range.According to the laser beam radiation model,the ratio values between two randomly selected channels’intensities at an identical target are independent of the range information and incident angle.To test the proposed method,the HSL was employed to scan a wall with different coloured papers pasted on it(white,red,yellow,pink,and green)at four distinct positions along a corridor(with an interval of 60 cm in between two consecutive positions).Then,a ratio value vector was constructed for each scan.The ratio value vectors between consecutive laser scans were employed to match the point cloud.A classic Iterative Closest Point(ICP)algorithm was employed to estimate the HSL motion using the range information from the matched point clouds.According to the test results,we found that pink and green papers were distinctive at 650,690,and 720 nm.A ratio value vector was constructed using 650-nm spectral information against the reference channel.Furthermore,compared with the classic ICP using range information only,the proposed method that matched ratio value vectors presented an improved performance in heading angle estimation.For the best case in the field test,the proposed method enhanced the heading angle estimation by 72%,and showed an average 25.5%improvement in a featureless spatial testing environment.The results of the primary test indicated that the proposed method has the potential to aid point cloud matching in typical SLAM of real scenarios. | Changhui Jiang Yuwei Chen Wenxin Tian Ziyi Feng Wei Li Chunchen Zhou Hui Shao Eetu Puttonen Juha Hyyppä | 2020 | Satellite Navigation2020，1，1： | 2 |
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