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Relationship between stand characteristics and soil properties of two typical forest plantations in the mountainous area of Western Sichuan, China

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Journal of Mountain Science 2019年第8期16卷 1816-1832页

作者： yanG Hao MIAO Ning LI Shao-cai MA Rui liao zi-yan WANG Wei-ping SUN Hai-long Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China

There is uncertainty and limited knowledge regarding stand characteristics and soil properties of middle-aged pure forest plantations in the mountainous area of Western Sichuan. Plantation forests are almost exclusively planted as monocultures in the Pengzhou forest farm in the western mountainous area of Sichuan Province. This study aimed to assess the spatial and ecological characteristics of middle-aged Cunninghamia lanceolata(Lamb.) Hook. and Cryptomeria fortunei Hooibr. in the Pengzhou forest farm. The relationships and differences between stand growth characteristics and forest soil composition were assessed on the two forests planted simultaneously within the same area and exposed to the same environmental conditions. Cr. fortunei grew sparse, and slower than Cun. lanceolata. Principal component analysis indicated that the soil properties in the Cr. fortunei plantation were better than those in the Cun. lanceolata plantation. Redundancy analysis revealed that the differences in stand structure were affected significantly by the total nitrogen content and pH value. Thus, we propose that Cr. fortunei is planted for priority consideration in the subtropical high mountain area. Further, tending operations and application of fertilizers need to be conducted in Cun. lanceolata forests. Based on theoretical and experimental data, the present study explains why local farmers are more willing to plant Cr. fortunei, and thus provides a useful theoretical reference for the development of sustainable plantations in the future.

关键词： Planted forest Stand structure Soil properties Cunninghamia lanceolata Cryptomeria fortunei Pioneer tree

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基于iOS平台的校园助手APP的设计与实现

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电脑知识与技术 2018年第1X期14卷 79-81页

作者：李艳平廖子炎北京信息科技大学计算机学院北京100101

该软件基于i OS平台开发,使用storyboard设计软件的视图,使用SQLite存储数据。主要为在校大学生提供个人日程、课程表、备忘录以及学校周边信息检索功能。通过实时全景地图,可使学生快速定位学校周边的餐饮、娱乐和交通等信息。

关键词： iOS平台 storyboard SQLite 信息检索地图

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西南地区壳斗科物种丰富度和特有性分布格局模拟及其环境解释

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应用生态学报 2021年第7期32卷 2290-2300页

作者：张凤英廖梓延潘开文张萌赵玉林张林四川省林业和草原调查规划院成都610081 中国科学院成都生物研究所成都610041 中国科学院大学北京100049

如何准确地模拟物种宏观丰富度格局和特有性中心是生物多样性保护工作的重点,也是生物地理学的热点话题。西南地区是我国壳斗科植物最丰富的地区之一,但物种多样性格局及环境驱动机制尚不清楚。本研究基于西南地区161种壳斗科植物7258... 详细信息

如何准确地模拟物种宏观丰富度格局和特有性中心是生物多样性保护工作的重点,也是生物地理学的热点话题。西南地区是我国壳斗科植物最丰富的地区之一,但物种多样性格局及环境驱动机制尚不清楚。本研究基于西南地区161种壳斗科植物7258个分布点位数据,利用点格局法和物种分布模型两种方式构建了物种丰富度、加权特有性指数和校正加权特有性指数的分布格局,并采用空间自回归模型(SAR)分析上述3个多样性指数与环境因子间的关系。总体上看,物种分布模型模拟的3个指数在空间上比点格局法更为连续,但数值高低分布情况具有相似性:两种方式模拟的物种丰富度高值区主要分布在滇南边缘、桂北部和桂西南部地区(62~89种);加权特有性指数最大值集中在滇南和桂西地区(1.77~5.02);藏东南、秦岭-大巴山、桂西南部和滇东南地区具有最高的校正加权特有性指数(0.07~0.17)。SAR模型结果显示:最干月降雨量、温度季节性变化标准差、海拔变幅和土壤有机碳含量对物种丰富度的影响均显著,最干月降雨量、温度季节性变化标准差、潜在蒸散量和海拔变幅对加权特有性有着显著影响,温度季节性变化标准差、最干月降雨量、历史温度变化、增强型植被指数变异系数和海拔变幅对校正加权特有性的影响显著;SAR模型对物种丰富度、特有性指数和加权特有性指数的拟合效果(R2=0.857、0.733、0.593)分别优于普通线性模型(R2=0.689、0.425、0.422)。综上,水分可获得性、气候季节性、生境异质性、历史气候变化和土壤状况是制约西南地区壳斗科丰富度和特有性分布的最重要因素。滇南、滇东南、桂西南、桂西、秦岭-大巴山以及藏东南地区是壳斗科物种丰富度中心或特有性中心,应受到重点关注和保护。

关键词：物种丰富度特有性水热状况生境异质性

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探讨英雄叙事的另一种可能性——评长篇小说《苍茫大地》

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徐州工程学院学报（社会科学版） 2017年第2期32卷 93-97页

作者：王晓华廖紫俨深圳大学文学院广东深圳518060

长篇小说《苍茫大地》讲述了一个基于19世纪上半叶中国时代背景下的红色故事:留学、归国、斗争、牺牲。小说在叙事过程中运用了多种艺术尝试,以此期冀建构一个反纪念碑化的英雄人物形象,进而探索了当代红色叙事学的另一种可能性。在英... 详细信息

长篇小说《苍茫大地》讲述了一个基于19世纪上半叶中国时代背景下的红色故事:留学、归国、斗争、牺牲。小说在叙事过程中运用了多种艺术尝试,以此期冀建构一个反纪念碑化的英雄人物形象,进而探索了当代红色叙事学的另一种可能性。在英雄叙事渐趋类型化的语境中,这种创新具有弥足珍贵的意义。

关键词：《苍茫大地》红色叙事学纪念碑性

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松栎林天然更新模拟与不确定性分析

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应用生态学报 2020年第12期31卷 4004-4016页

作者：王彬田相林廖梓延王志涛耿生莲曹田健西北农林科技大学林学院陕西杨凌712100 生态仿真优化实验室陕西杨凌712100 青海大学农林科学院西宁810016 中国科学院成都生物研究所成都610041

森林天然更新的复杂性和不确定性是森林生态系统动态预测中的关键问题。本研究引入贝叶斯技术和全局敏感性分析,构建基于竞争、气候和地形3类因子的秦岭松栎林天然更新模型。备选模型形式以泊松(Poisson)模型、负二项(negative binomial... 详细信息

森林天然更新的复杂性和不确定性是森林生态系统动态预测中的关键问题。本研究引入贝叶斯技术和全局敏感性分析,构建基于竞争、气候和地形3类因子的秦岭松栎林天然更新模型。备选模型形式以泊松(Poisson)模型、负二项(negative binomial,NB)模型、零膨胀泊松(zero-inflated Poisson,ziP)模型和零膨胀负二项(zero-inflated negative binomial,ziNB)模型为基础。同时,根据模型参数传递的不确定性量化分析结果,阐释影响森林更新小概率事件的主导因子。结果表明:ziNB模型在油松和锐齿栎更新模拟中均优于其他模型。林分总断面积、光截留、坡位和生长季最低温是影响松栎林中油松天然更新的最关键因子;而林分总断面积、坡向与海拔的组合、年均温和最热季节降水量则是影响松栎林中锐齿栎天然更新的关键因子。油松更新模拟中,各类因子对模型输出的不确定性贡献率从小到大依次为:竞争因子(25%)ziNB模型可以量化森林更新的影响因子,并解释参数传递的不确定性,是预测森林天然更新的有力工具。

关键词：气候敏感性贝叶斯技术不确定性天然更新油松锐齿栎

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Human-induced pluripotent stem cell-derived neural stem cell exosomes improve blood-brain barrier function after intracerebral hemorrhage by activating astrocytes via PI3K/AKT/MCP-1 axis

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Neural Regeneration Research 2025年第2期20卷 518-532页

作者： Conglin Wang Fangyuan Cheng Zhaoli Han Bo yan Pan liao Zhenyu Yin Xintong Ge Dai Li Rongrong Zhong Qiang Liu Fanglian Chen Ping Lei Department of Geriatrics Tianjin Medical University General HospitalTianjinChina School of Medicine Nankai UniversityTianjinChina Tianjin Neurological Institute TianjinChina

Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor ***-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)have shown potential for brain injury repair in central nervous system *** this study,we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying *** results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits,enhanced blood-brain barrier integrity,and reduced leukocyte infiltration in a mouse model of intracerebral ***,hiPSC-NSC-Exos decreased immune cell infiltration,activated astrocytes,and decreased the secretion of inflammatory cytokines like monocyte chemoattractant protein-1,macrophage inflammatory protein-1α,and tumor necrosis factor-αpost-intracerebral hemorrhage,thereby improving the inflammatory *** sequencing indicated that hiPSC-NSC-Exo activated the PI3K/AKT signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion,thereby improving blood-brain barrier *** with the PI3K/AKT inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these *** summary,our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity,in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3K/AKT signaling pathway in astrocytes.

关键词： AKT astrocyte blood-brain barrier cerebral edema exosomes human-induced pluripotent stem cells intracerebral hemorrhage neural stem cells neuroinflammation PI3K

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High-temperature-tolerant flexible supercapacitors: Gel polymer electrolytes and electrode materials

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Journal of Energy Chemistry 2025年第1期100卷 426-457页

作者： Chong Peng Xinyi Huang Mingwei Zhao Shuling liao Quanhong yang Nianjun yang Siyu Yu School of Chemistry & Chemical Engineering Southwest University Nanoyang Group Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage School of Chemical Engineering and Technology and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University Department of Chemistry & IMO-IMOMEC Hasselt University

The development of flexible supercapacitors(FSCs) capable of operating at high temperatures is crucial for expanding the application areas and operating conditions of supercapacitors. Gel polymer electrolytes and electrode materials stand as two key components that significantly impact the efficacy of hightemperature-tolerant FSCs(HT-FSCs). They should not only exhibit high electrochemical performance and excellent flexibility, but also withstand intense thermal stress. Considerable efforts have been devoted to enhancing their thermal stability while maintaining high electrochemical and mechanical performance. In this review, the fundamentals of HT-FSCs are outlined. A comprehensive overview of state-of-the-art progress and achievements in HT-FSCs, with a focus on thermally stable gel polymer electrolytes and electrode materials is provided. Finally, challenges and future perspectives regarding HT-FSCs are discussed, alongside strategies for elevating operational temperatures and *** review offers both theoretical foundations and practical guidelines for designing and manufacturing HT-FSCs, further promoting their widespread adoption across diverse fields.

关键词： Flexible supercapacitors High-temperature tolerance Gel polymer electrolytes Electrode materials

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难美项群水平控腿立转360°难度动作的运动学分析

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福建体育科技 2021年第6期40卷 53-58页

作者：邓俊臣张舒昊杜熙茹廖子彦广州体育学院广东广州510500 华南师范大学体育科学学院广东广州510006

以体操、艺术体操和竞技健美操三个难美项群中共有的水平控腿立转360°难度动作为研究对象,运用高精度光学三维动作捕捉系统,捕获三名不同项目高水平运动员在完成难度的摆臂蹬伸时相和水平控腿转体时相的相关运动学参数,并探讨难美项群... 详细信息

以体操、艺术体操和竞技健美操三个难美项群中共有的水平控腿立转360°难度动作为研究对象,运用高精度光学三维动作捕捉系统,捕获三名不同项目高水平运动员在完成难度的摆臂蹬伸时相和水平控腿转体时相的相关运动学参数,并探讨难美项群不同项目之间的运动学特征。研究表明:1.摆臂蹬伸时相末段形成较大的肩髖扭转角能够提升重心角速度;2.合理的蹬摆技术能够降低转动半径和角加速度,进而减小转动惯量,保证转体时相各身体环节角度的合理性,才能提升重心稳定性和动能转化率;3.相比较而言体操运动员MO的水平控腿立转360°动作技术,对其他难美项群的旋转类难度练习具有较强的指导意义。

关键词：难美项群水平控腿立转难度动作运动学分析

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Robust spatio-temporal error concealment for packet- lossy H.264 video transmission

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 87-92页

作者： liao Ning yan Dan QUAN zi-yi MEN Ai-dong Multimedia Center Beijing University of Posts and TelecommunicationsBeijing 100876 China

In this article, a spatio-temporal post-processing error concealment algorithm designed initially for a H.264 video-streaming scheme over packet-lossy networks has been presented. It aims at optimizing subjective quality of restored video and the conventional objective metric, peak signal-to-noise ratio （PSNR）, as well, under the constraints of low delay and computational complexity, which are critical to real-time applications and portable devices having limited resources. Specifically, it takes into consideration physical property of motion to achieve more meaningful perceptual video quality. Further, a content-adaptive bilinear spatial interpolation approach and a temporal error concealment approach are combined under a unified boundary match criterion based on texture and motion activity analysis. Extensive experiments have demonstrated that the proposal not only result in better reconstruction, objectively and subjectively, than the reference software model benchmark, but also results in better robustness to different video sequences.

关键词： error concealment error control H.264/JVT video transmission lossy transmission

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Content-adaptive robust error concealment for packet-lossy H.264 video streaming

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 41-47页

作者： liao Ning yan Dan QUAN zi-yi MEN Ai-dong Multimedia Center School of Telecommunication Engineering Beijing University of Posts & Telecom Beijing 100876 China Multimedia Center School of Telecommunication Engineering Beijing University of Posts & Telecom Beijing 100876 China Multimedia Center School of Telecommunication Engineering Beijing University of Posts & Telecom Beijing 100876 China Multimedia Center School of Telecommunication Engineering Beijing University of Posts & Telecom Beijing 100876 China

In this paper, we present a spatio-temporal post-processing error concealment (EC) algorithm designed initially for a H.264 video-streaming scheme over packet-lossy networks. It aims at optimizing the subjective quality of the restored video under the constraints of low delay and computational complexity, which are critical to real-time applications and portable devices having limited resources. Specifically, it takes into consideration the physical property of motion field in order to achieve more meaningful perceptual video quality, in addition to the improved objective PSNR. Further, a simple bilinear spatial interpolation approach is combined with the improved boundary-match (B-M) based temporal EC approach according to texture and motion activity analysis. Finally, we propose a low complexity temporal EC method based on motion vector interpolation as a replacement of the B-M based approach in the scheme under low-computation requirement, or as a complement to further improve the scheme's performance in applications having enough computation resources. Extensive experiments demonstrated that the proposal features not only better reconstruction, objectively and subjectively, than JM benchmark, but also robustness to different video sequences.

关键词： Error concealment, Error control, H.264/AVC, Video streaming, Lossy transmission

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