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Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains,China

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Journal of Forestry Research 2024年第2期35卷 197-208页

作者： Jinkuan Li Jianfeng peng xiaoxu Wei Meng peng Xuan Li Yameng Liu Jiaxin Li College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Key Laboratory of Earth System Observation and Simulation of Henan Province Kaifeng 475004People’s Republic of China

Global warming will affect growth strategies and how trees will adapt.To compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and treering chronologies developed on northern and western slopes from the Lubanling in the Funiu Mountains.Correlation analyses showed that two chronologies were mainly limited by temperatures in the previous June–August and the combination of temperatures and moisture in the current May–July.The difference of the climate response to slopes was small but not negligible.Radial growth of the LBL01 site on the northern slope was affected by the combined maximum and minimum temperatures,while that of the LBL02 site was affected by maximum temperatures.With regards to moisture,radial growth of the trees on the north slope was influenced by the relative humidity in the current May–July,while on the western slope,it was affected by the relative humidity in the previous June–August,the current May–July and the precipitation in the current May–July.With the change in climate,the effects of the main limiting factors on growth on different slopes were visible to a certain extent,but the differences in response of trees on different slopes gradually decreased,which might be caused by factors such as different slope directions and the change in diurnal temperature range.These results may provide information for forest protection and ecological construction in this region,and a scientific reference for future climate reconstruction.

关键词： Tree ring width Lubanling Pinus armandii Franch Slope direction Climate response

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Climate-growth relationships of Pinus tabuliformis along an altitudinal gradient on Baiyunshan Mountain,Central China

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Journal of Forestry Research 2024年第1期35卷 202-212页

作者： xiaoxu Wei Jianfeng peng Jinbao Li Jinkuan Li Meng peng Xuan Li Yameng Liu Jiaxin Li College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Key Laboratory of Earth System Observation and Simulation of He’nan Province Kaifeng 475004People’s Republic of China Department of Geography University of Hong KongPokfulamHong Kong SARPeople’s Republic of China HKU Shenzhen Institute of Research and Innovation Shenzhen 518057People’s Republic of China

A set of standard chronologies for tree-ring width(TRW),earlywood width(EWW)and latewood width(LWW)in Pinus tabuliformis Carr.along an altitudi-nal gradient(1450,1400,and 1350 m a.s.l.)on Baiyunshan Mountain,Central China to analyze the effect of varying temperature and precipitation on growth along the gradi-ent.Correlation analyses showed that at all three altitudes and the TRW and EWW chronologies generally had signifi-cant negative correlations with mean and maximum tem-peratures in the current April and May and with minimum temperatures in the prior July and August,but significant positive correlations with precipitation in the current May.Correlations were generally significantly negative between LWW chronologies and all temperatures in the prior July and August,indicating that the prior summer temperature had a strong lag effect on the growth of P.tabuliformis that increased with altitude.The correlation with the standard-ized precipitation evapotranspiration index(SPEI)confirmed that wet conditions in the current May promoted growth of TR and EW at all altitudes.Significant altitudinal differences were also found;at 1400 m,there were significant positive correlations between EWW chronologies and SPEI in the current April and significant negative correlations between LWW chronologies and SPEI in the current September,but these correlations were not significant at 1450 m.At 1350 m,there were also significant negative correlations between the TRW and the EWW chronologies and SPEI in the prior October and the current July and between LWW chronology and SPEI in the current August,but these cor-relations were not significant at 1400 m.Moving correlation results showed a stable response of EWW in relation to the SPEI in the current May at all three altitudes and of LWW to maximum temperature in the prior July-August at 1400 m from 2002 to 2018.The EWW chronology at 1400 m and the LWW chronology at 1450 m were identified as more suitable for climate reconstruction.These results provide a strong scientific basis f

关键词： Tree rings Climate response Altitudinal gradient Baiyunshan Mountain Pinus tabuliformis Carr

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RRT Autonomous Detection Algorithm Based on Multiple Pilot Point Bias Strategy and Karto SLAM Algorithm

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Computers, Materials & Continua 2024年第2期78卷 2111-2136页

作者： Lieping Zhang xiaoxu Shi Liu Tang Yilin Wang Jiansheng peng Jianchu Zou Key Laboratory of Advanced Manufacturing and Automation Technology(Guilin University of Technology) Education Department of Guangxi Zhuang Autonomous RegionGuilin541006China College of Mechanical and Control Engineering Guilin University of TechnologyGuilin541006China Guilin Mingfu Robot Technology Company Limited Guilin541199China Key Laboratory of AI and Information Processing(Hechi University) Education Department of Guangxi Zhuang Autonomous RegionYizhou546300China

A Rapid-exploration Random Tree(RRT)autonomous detection algorithm based on the multi-guide-node deflection strategy and Karto Simultaneous Localization and Mapping(SLAM)algorithm was proposed to solve the problems of low efficiency of detecting frontier boundary points and drift distortion in the process of map building in the traditional RRT algorithm in the autonomous detection strategy of mobile robot.Firstly,an RRT global frontier boundary point detection algorithm based on the multi-guide-node deflection strategy was put forward,which introduces the reference value of guide nodes’deflection probability into the random sampling function so that the global search tree can detect frontier boundary points towards the guide nodes according to random probability.After that,a new autonomous detection algorithm for mobile robots was proposed by combining the graph optimization-based Karto SLAM algorithm with the previously improved RRT algorithm.The algorithm simulation platform based on the Gazebo platform was built.The simulation results show that compared with the traditional RRT algorithm,the proposed RRT autonomous detection algorithm can effectively reduce the time of autonomous detection,plan the length of detection trajectory under the condition of high average detection coverage,and complete the task of autonomous detection mapping more efficiently.Finally,with the help of the ROS-based mobile robot experimental platform,the performance of the proposed algorithm was verified in the real environment of different obstacles.The experimental results show that in the actual environment of simple and complex obstacles,the proposed RRT autonomous detection algorithm was superior to the traditional RRT autonomous detection algorithm in the time of detection,length of detection trajectory,and average coverage,thus improving the efficiency and accuracy of autonomous detection.

关键词： Autonomous detection RRT algorithm mobile robot ROS Karto SLAM algorithm

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Systematic evaluation of advance in application and discharge mechanism of solution electrode glow discharge

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Chinese Chemical Letters 2022年第1期33卷 61-70页

作者： xiaoxu peng Zheng Wang Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

As a kind of microplasma sustained in air,solution electrode glow discharge(SEGD)ignited between the liquid electrode and metal electrode is attractive to the fields of optical emission spectrometry and mass spectrometry due to its unique advantages,such as low power consumption and low carrier gas consumption.Moreover,the complex and efficient reactions in the liquid phase and plasma phase of SEGD make it considerable research potential in the fields of biology and medicine,material synthesis,electrochemistry.Considering the close relationship between the various fields on SEGD,here we are devoted to provide an overview of the development of SEGD in various fields.More importantly,a systematic discussion on the discharge mechanism is conducted based on the research process in various fields for getting deeper insight into the SEGD.

关键词： Solution cathode glow discharge Solution anode glow discharge Mass spectrometry Optimal emission spectroscopy Discharge mechanism

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Microenvironmental effects on growth response of Pinus massoniana to climate at its northern boundary in the Tongbai Mountains,Central China

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Journal of Forestry Research 2024年第1期35卷 44-57页

作者： Jianfeng peng Jiayue Cui Jinbao Li Meng peng Yongtao Ma xiaoxu Wei Jinkuan Li Xuan Li Yamen Liu Jiaxin Li College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Key Laboratory of Earth System Observation and Simulation of Henan Province Kaifeng 475004People’s Republic of China Department of Geography University of Hong KongHong KongSARPeople’s Republic of China HKU Shenzhen Institute of Research and Innovation Shenzhen 518057People’s Republic of China Henan Academy of Forestry Zhengzhou 450000People’s Republic of China

The Tongbai Mountains is an ecologically sensi-tive region and the northern boundary of Pinus massoniana Lamb.To analyze the effect of different microenvironments on tree growth response to climate factors,we developed standard chronologies for earlywood width(EWW),late-wood width(LWW),and total ring width(TRW)of P.massoniana at two sampling sites on slopes with different orientations,then analyzed characteristics of the chronolo-gies and their correlations with climate variables from five stations in the region and with a regional normalized differ-ence vegetation index(NDVI).Statistical results showed that the TRW/EWW/LWW chronology consistency and charac-teristics(mean sensitivity,signal to noise ratio,expressed population signal)for trees growing on the southeastern slope were much higher than for trees on the northeastern slope.Correlations indicated that temperature in current March and August has a significant positive effect on TRW/EWW/LWW formation,and the effect on the northeastern slope was weaker than on the southeastern slope.Compared to temperature,precipitation has more complicated effects on tree growth,but the effect on the northeastern slope was also generally weaker than on the southeastern slope.Step-wise linear regression analyses showed that temperature in August was the main limiting factor at the two sampling sites.Similarly,the response of tree growth on the southeast-ern slope as determined by the NDVI is better than on the northeastern slope,and the TRW/EWW/LWW chronologies for the southeastern slope explained over 50%of the total NDVI variances in June.Overall,the results indicate that the difference in the climate response of P.massoniana at two sampling sites is clearly caused by differences in the microenvironment,and such differences should be properly considered in future studies of forest dynamics and climate reconstructions.

关键词： Tree-rings Pinus massoniana lamb Microenvironment Radial growth Climate-growth response

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Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains, China

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Journal of Forestry Research 2024年第3期 88-99页

作者： Jinkuan Li Jianfeng peng xiaoxu Wei Meng peng Xuan Li Yameng Liu Jiaxin Li College of Geography and Environmental Science Henan University Key Laboratory of Earth System Observation and Simulation of Henan Province

Global warming will affect growth strategies and how trees will adapt. To compare the response of tree radial growth to climate warming in different slope directions, samples of Pinus armandii Franch were collected and treering chronologies developed on northern and western slopes from the Lubanling in the Funiu Mountains. Correlation analyses showed that two chronologies were mainly limited by temperatures in the previous June–August and the combination of temperatures and moisture in the current May–July. The difference of the climate response to slopes was small but not negligible. Radial growth of the LBL01 site on the northern slope was affected by the combined maximum and minimum temperatures, while that of the LBL02 site was affected by maximum temperatures. With regards to moisture, radial growth of the trees on the north slope was influenced by the relative humidity in the current May–July, while on the western slope, it was affected by the relative humidity in the previous June–August, the current May–July and the precipitation in the current May–July. With the change in climate, the effects of the main limiting factors on growth on different slopes were visible to a certain extent, but the differences in response of trees on different slopes gradually decreased, which might be caused by factors such as different slope directions and the change in diurnal temperature range. These results may provide information for forest protection and ecological construction in this region, and a scientific reference for future climate reconstruction.

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Stability assessment of tree ring growth of Pinus armandi Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains,China

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Journal of Forestry Research 2024年第3期35卷 87-98页

作者： Jinkuan Li Jianfeng peng xiaoxu Wei Meng peng Xuan Li Yameng Liu Jiaxin Li College of Geography and Environmental Science Henan UniversityKaifeng 475004People's Republic of China Key Laboratory of Earth System Observation and Simulation of Henan Province Kaifeng 475004People's Republic of China

Global warming will affect growth strategies and how trees will adapt.To compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and tree-ring chronologies developed on northern and western slopes from the Lubanling in the Funiu Mountains.Correlation analyses showed that two chronologies were mainly limited by temperatures in the previous June-August and the com-bination of temperatures and moisture in the current May-July.The difference of the climate response to slopes was small but not negligible.Radial growth of the LBLO1 site on the northern slope was affected by the combined maximum and minimum temperatures,while that of the LBLO2 site was affected by maximum temperatures.With regards to moisture,radial growth of the trees on the north slope was influenced by the relative humidity in the current May-July,while on the western slope,it was affected by the relative humidity in the previous June-August,the current May-July and the precipitation in the current May-July.With the change in climate,the effects of the main limiting factors on growth on different slopes were visible to a certain extent,but the differences in response of trees on different slopes gradually decreased,which might be caused by factors such as different slope directions and the change in diurnal temperature range.These results may provide information for forest protection and ecological construction in this region,and a scientific reference for future climate reconstruction.

关键词： Tree ring width Lubanling Pinus armandi Franch Slope direction Climate response

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Ultrasensitive determination of mercury by solution anode glow discharge atomic emission spectrometry coupled with hydride generation

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Chinese Chemical Letters 2020年第10期31卷 2814-2818页

作者： Mingli Yuan xiaoxu peng Fen Ge Mingyue Zhao Qing Li Zheng Wang Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Material Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China

An innovative method for the ultrasensitive detection of mercury by solution anode glow discharge atomic emission spectroscopy(SAGD-AES) coupled with hydride generation(HG) was first investigated.In this method,the mercury vapor generated by the HG was transmitted to the SAGD through the miniature hollow tungsten tube for excitation and detected by a miniaturized spectrograph.A thorough parametric evaluation of the HG and SAGD system was performed,including the type and concentration of ca rrier acid,He flow rate,concentrations of NaBH4,discha rge current and discharge gap.Under optimal operating conditions,the detection limit for Hg^(2+) achieved 0.03 μg/L,with a relative standard deviation of 1.1% at the Hg^(2+) concentration of 5 μg/L.Moreover,the correlation coefficient of the calibration curve was 0.9996 in the range between 0.1 and 10 μg/L.The accuracy and practicability of HG-SAGD-AES were verified by measuring GBW09101 b(human hair),GBW10029(fish),soil and rice samples.The results showed good agreement with the certified values and values from direct mercury analyzer(DMA).

关键词： Solution anode glow discharge Hydride generation Atomic emission spectroscopy Mercury

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注射用己酮可可碱联合奥扎格雷钠治疗急性脑梗死的临床研究

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现代药物与临床 2024年第6期39卷 1473-1478页

作者：邓艳梅彭伟王晓旭北京市丰台中西医结合医院神经内科

目的分析注射用己酮可可碱联合奥扎格雷钠治疗急性脑梗死的临床疗效。方法选取2015年3月—2020年10月北京市丰台中西医结合医院收治的112例急性脑梗死患者，按随机数字表法将患者分为对照组和治疗组，每组各56例。对照组静脉滴注注射... 详细信息

目的分析注射用己酮可可碱联合奥扎格雷钠治疗急性脑梗死的临床疗效。方法选取2015年3月—2020年10月北京市丰台中西医结合医院收治的112例急性脑梗死患者，按随机数字表法将患者分为对照组和治疗组，每组各56例。对照组静脉滴注注射用奥扎格雷钠，80 mg/次，溶于500 mL生理盐水中，2次/d。治疗组在对照组治疗基础上静脉滴注注射用己酮可可碱，0.2 g/次，溶于250 mL生理盐水中，1次/d，输注过程中患者平卧，2～3 h内滴注完成。两组疗程均为14 d。观察两组的临床疗效，比较两组治疗前后美国国立卫生研究院卒中量表（NIHSS）评分、简式Fugl-Meyer评定量表（FMA）评分、脑卒中专门化生存质量量表（SS-QOL）评分及血小板压积（PCT）、血小板聚集率（PAg T）、纤维蛋白原（FIB）和炎症相关指标[中性粒细胞与淋巴细胞比值（NLR）、血小板与淋巴细胞比值（PLR）]的变化。结果治疗后，治疗组总有效率是94.64%，显著高于对照组的82.14%(P<0.05)。治疗3、7、14 d后，两组NIHSS评分均较同组治疗前显著降低（P<0.05）；治疗后，治疗组患者NIHSS评分显著低于对照组（P<0.05）。治疗后，两组FMA、SS-QOL评分均较治疗前显著增加（P<0.05）；治疗后，治疗组FMA、SS-QOL评分高于对照组（P<0.05）。治疗后，两组PCT、PAgT、FIB、NLR、PLR均显著下降（P<0.05）；治疗后，治疗组凝血及炎症相关指标显著低于对照组（P<0.05）。结论注射用己酮可可碱联合奥扎格雷钠治疗急性脑梗死的效果确切，能在较佳的安全性基础上，有效促进患者神经功能、运动功能恢复，改善凝血功能紊乱和机体炎症损害，利于患者生存状态提升。

关键词：注射用己酮可可碱注射用奥扎格雷钠急性脑梗死美国国立卫生研究院卒中量表评分简式Fugl-Meyer评定量表评分脑卒中专门化生存质量量表评分血小板压积血小板聚集率纤维蛋白原中性粒细胞与淋巴细胞比值

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应用改进RRT_Connect算法的移动机器人路径规划

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科技导报 2024年第8期42卷 111-119页

作者：史小旭张烈平唐柳董路熙彭建盛广西高校先进制造与自动化技术重点实验室桂林541006 贺州学院人工智能学院贺州542899 广西高校人工智能与信息处理重点实验室河池546300

针对复杂未知环境下的移动机器人路径规划问题,提出一种优化已搜索节点和已规划部分路径的改进RRT_Connect算法。算法引入了终点和已搜索节点目标偏向策略,该策略在随机采样函数中引入终点和已搜索节点偏向概率基准值,使随机采样点按随... 详细信息

针对复杂未知环境下的移动机器人路径规划问题,提出一种优化已搜索节点和已规划部分路径的改进RRT_Connect算法。算法引入了终点和已搜索节点目标偏向策略,该策略在随机采样函数中引入终点和已搜索节点偏向概率基准值,使随机采样点按随机概率设定为终点或已搜索节点;通过筛选有效新节点和一定范围内邻节点的父节点,优化路径规划成本,使规划路径趋于平滑。仿真结果表明,提出的改进RRT_Connect算法所规划的路径在平均转弯次数、平均规划路径长度和平均规划成功率等指标较改进前更优。

关键词： RRT_Connect算法移动机器人路径规划目标偏向策略

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