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基于叠加训练序列的低复杂度时变信道估计方案

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电子与信息学报 2013年第9期35卷 2194-2199页

作者：何纯全窦高奇高俊黄高明海军工程大学电子工程学院武汉430033

与传统的时分/频分复用训练序列相比,采用叠加训练序列的传输方案可以有效地提高系统的频谱利用率。然而,叠加方案中训练序列与信息序列的相互干扰会造成系统性能的严重下降,如何有效消除信息干扰是提高信道估计性能的关键。该文针对时... 详细信息

与传统的时分/频分复用训练序列相比,采用叠加训练序列的传输方案可以有效地提高系统的频谱利用率。然而,叠加方案中训练序列与信息序列的相互干扰会造成系统性能的严重下降,如何有效消除信息干扰是提高信道估计性能的关键。该文针对时变衰落信道,首先提出一种新的基于一阶统计量信道估计算法。该算法利用基扩展模型(BEM)构建时变信道,通过时域分块平均的方法来抑制信息序列干扰。在此基础上,利用信息序列和训练序列经历相同信道衰落的特性,提出一种基于加权最小二乘(WLS)的迭代信道估计与检测方案。新方案利用Kalman滤波检测器代替确定性最大似然(DML)检测器,将检测符号序列看作附加的"训练序列"用于信道估计,从而可以显著提高信道估计性能。仿真结果表明,新方案可以有效消除信息序列干扰,且性能和计算复杂度均优于现有的同类方案。

关键词：无线通信叠加训练序列时变信道干扰消除迭代信道估计与检测

HY5-HDA9 Module Transcriptionally Regulates Plant Autophagy in Response to Light-to-Dark Conversion and Nitrogen Starvation

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Molecular Plant 2020年第3期13卷 515-531页

作者： Chao Yang Wenjin Shen Lianming Yang Yun Sun Xibao Li Minyi Lai Juan Wei Chaojun Wang Yingchao Xu Faqiang Li Shan Liang Chengwei Yang Shangwei Zhong ming Luo Caiji gao Guangdong Provincial Key Laboratory of Biotechnology for Plant Development School of Life SciencesSouth China Normal UniversityGuangzhou 510631China Guangdong Provincial Key Laboratory of Applied Botany Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic ImprovementSouth China Botanical GardenCore Botanical GardensChinese Academy of SciencesGuangzhou 510650China College of Life Sciences Leshan Normal UniversityLeshan 614004China College of Life Sciences South China Agricultural UniversityGuangzhou 510642China School of Advanced Agricultural Sciences and School of Life Sciences Peking University100871 BeijingChina Center of Economic Botany Core Botanical GardensChinese Academy of SciencesGuangzhou 510650China These authors contributed equally to this article

Light is arguably one of the most important environmental factors that determines virtually all aspects of plant growth and development,but the molecular link between light signaling and the autophagy pathway has not been elucidated in *** this study,we demonstrate that autophagy is activated during light-to-dark conversion though transcriptional upregulation of autophagy-related genes(ATGs).We showed that depletion of the ELONGATED HYPOCOTYL 5(HY5),a key component of light signaling,leads to enhanced autophagy activity and resistance to extended darkness and nitrogen starvation treatments,contributing to higher expression ***5 interacts with and recruits HISTONE DEACETYLASE 9(HDA9)to ATG5 and ATG8e loci to repress their expression by deacetylation of the Lys9 and Lys27 of histone ***,we found that both darkness and nitrogen depletion induce the degradation of HY5 via 26S proteasome and the concomitant disassociation of HDA9 from ATG5 and ATG8e loci,leading to their depression and thereby activated *** analysis further confirmed that HY5 and HDA9 act synergistically and function upstream of the autophagy ***,our study unveils a previously unknown transcriptional and epigenetic network that regulates autophagy in response to light-to-dark conversion and nitrogen starvation in plants.

关键词： autophagy histone acetylation HY5 HDA9 light-to-dark shift nitrogen starvation

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固结比对黏性土动剪切模量影响的研究

岩土力学 2010年第5期31卷 1457-1462,1468页

作者：孙静袁晓铭黑龙江大学建筑工程学院哈尔滨150086 中国地震局工程力学研究所哈尔滨150080

采用共振柱试验方法,对固结比对黏性土最大动剪切模量和对动剪切模量比与剪应变非线性关系的影响进行了研究,并通过土层地震反应计算,初步给出了这种影响对地表反应谱作用的估计。通过对粉质黏土和粉土的系统试验,提出了计算不同固结比... 详细信息

采用共振柱试验方法,对固结比对黏性土最大动剪切模量和对动剪切模量比与剪应变非线性关系的影响进行了研究,并通过土层地震反应计算,初步给出了这种影响对地表反应谱作用的估计。通过对粉质黏土和粉土的系统试验,提出了计算不同固结比粉质黏土和粉土最大动剪切模量的建议公式,并与Hardin公式进行了对比。结果显示,固结比kc>1.0时的最大动剪切模量较kc=1.0时的增长程度明显比Hardin公式要大。与砂土试验结果相比,固结比对黏性土最大动剪切模量影响程度更大。同时,分析了固结比对动剪切模量比与剪应变非线性关系及对地表反应谱的影响。结果表明,固结比对黏性土动剪切模量比与剪应变非线性关系有一定影响,随固结比增加,动剪切模量比非线性关系曲线有一定提高,动剪切模量比值增大,在强地震动作用下的土层反应分析中应考虑实际固结比的影响。

关键词：固结比动剪切模量黏性土共振柱试验反应谱

Comparative analysis of the genome of the field isolate V86010 of the rice blast fungus Magnaporthe oryzae from Philippines

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Journal of Integrative Agriculture 2017年第10期16卷 2222-2230页

作者： ZHU Kun-peng BAO Jian-dong ZHANG Lian-hu YANG Xue LI yuan ZHU ming-hui LIN Qing-yun ZHAO Ao ZHAO Zhen ZHOU Bo LU Guo-dong State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China Key Laboratory of Biopesticide and Chemistry Biology Ministry of Education Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China International Rice Research Institute Metro Manila DAPO Box 7777 Philippines

Genome dynamics of pathogenic organisms are driven by plant host and pathogenic organism co-evolution, in which patho- gen genomes areused to overcome stresses imposed by hosts with various genetic backgrounds through generation of a range of field isolates. This model also applies to the rice host and its fungal pathogen Magnaporthe oryzae. To better understand genetic variation of M. oryzae in nature, the field isolate V86010 from the Philippines was sequenced and ana- lyzed. Genome annotation found that the assembled V86010 genome was composed of 1 931 scaffolds with a combined length of 38.9 Mb. The average GC ratio is 51.3% and repetitive elements constitute 5.1% of the genome. A total of 11 857 genes including 616 effector protein genes were predicted using a combined analysis pipeline. All predicted genes and effector protein genes of isolate V86010 distribute on the eight chromosomes when aligned with the assembled genome of isolate 70-15. Effector protein genes are located disproportionately at several chromosomal ends. The Pot2 elements are abundant in V86010. Seven V86010-specific effector proteins were found to suppress programmed cell death induced by BAX in tobacco leaves using an Agrobacterium-mediated transient assay. Our results may provide useful information for further study of the molecular and genomic dynamics in the evolution of M. oryzae and rice host interactions, and for characterizing novel effectors and AVR genes in the rice blast pathogen.

关键词： Magnaporthe oryzae genetic variation comparative genomics effectors avirulence genes

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复合材料飞轮结构及强度设计研究进展

兵工学报 2006年第4期27卷 750-756页

作者：秦勇夏源明中国兵器工业系统总体部北京100089 中国科学技术大学力学和机械工程系安徽合肥230027

复合材料飞轮储能系统结合了新材料技术、磁悬浮技术、高速可逆电机技术等,使得飞轮系统的储能密度大大提高,并引起了各国科技部门的高度关注。飞轮本体的结构和强度设计作为飞轮系统中的理论性的问题一直没有形成系统完整的分析方法,... 详细信息

复合材料飞轮储能系统结合了新材料技术、磁悬浮技术、高速可逆电机技术等,使得飞轮系统的储能密度大大提高,并引起了各国科技部门的高度关注。飞轮本体的结构和强度设计作为飞轮系统中的理论性的问题一直没有形成系统完整的分析方法,针对这一问题进行了概述,指出了现有模型的不足,为建立系统完整的复合材料飞轮强度设计方法提出了建议。

关键词：复合材料复合材料飞轮储能密度结构和强度设计多环过盈装配张紧力缠绕

Scorpiones,Scolopendra and Gekko Inhibit Lung Cancer Growth and Metastasis by Ameliorating Hypoxic Tumor Microenvironment via PI3K/AKT/mTOR/HIF-1αSignaling Pathway

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Chinese Journal of Integrative Medicine 2024年第9期30卷 799-808页

作者： MAO Qi-yuan WANG Xue-qian LIN Fei YU ming-wei FAN Hui-ting ZHENG Qi LIU Lan-chun ZHANG Chu-chu LI Dao-rui LIN Hong-sheng Department of Oncology Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China Department of Oncology Beijing Hospital of Traditional Chinese MedicineCapital Medical UniversityBeijing100010China Department of Cardiology Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China Institute of Traditional Chinese Medicine Information China Academy of Chinese Medical SciencesBeijing100700China

Objective:To investigate whether Buthus martensii karsch(Scorpiones),Scolopendra subspinipes mutilans ***(Scolopendra)and Gekko gecko Linnaeus(Gekko)could ameliorate the hypoxic tumor microenvironment and inhibit lung cancer growth and metastasis by regulating phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin/hypoxia-inducible factor-1α(PI3K/AKT/mTOR/HIF-1α)signaling ***:Male C57BL/6J mice were inoculated with luciferase labeled LL/2-luc-M38 cell suspension to develop lung cancer models,with rapamycin and cyclophosphamide as positive *** methyl cellulose solutions of Scorpiones,Scolopendra and Gekko were administered intragastrically as 0.33,0.33,and 0.83 g/kg,respectively once daily for 21 *** expression were detected every 7 days after inoculation,and tumor growth curves were *** was performed to determine CD31 and HIF-1αexpressions in tumor tissue and microvessel density(MVD)was *** blot was performed to detect the expression of PI3K/AKT/mTOR/HIF-1αsignaling pathway-related ***-linked immunosorbent assay was performed to detect serum basic fibroblast growth factor(bFGF),transforming growth factor-β1(TGF-β1)and vascular endothelial growth factor(VEGF)in ***:Scorpiones,Scolopendra and Gekko prolonged the survival time and inhibited lung cancer metastasis and expression of HIF-1α(all P<0.01).Moreover,Scorpiones,Scolopendra and Gekko inhibited the phosphorylation of AKT and ribosomal protein S6 kinase(p70S6K)(P<0.05 or P<0.01).In addition,they also decreased the expression of CD31,MVD,bFGF,TGF-β1 and VEGF compared with the model group(P<0.05 or P<0.01).Conclusion:Scorpiones,Scolopendra and Gekko all showed beneficial effects on lung cancer by ameliorating the hypoxic tumor microenvironment via PI3K/AKT/mTOR/HIF-1αsignaling pathway.

关键词： Scorpiones Scolopendra Gekko dredging collaterals and activating blood Chinese medicine of worms lung cancer hypoxic tumor microenvironment phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin/hypoxia-inducible factor-1α signaling pathway

Unraveling the catalytic redox mechanism of lithium–sulfur batteries through advanced in-situ/operando characterizations

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Science China Chemistry 2024年

作者： Pan Zeng Cheng yuan Bin Su Genlin Liu Jiechang gao Kun Yang Qingyuan Wang Liang Zhang Institute for Advanced Study School of Mechanical Engineering Chengdu University Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Dyson School of Design Engineering Imperial College London

Accelerating the redox conversion of lithium polysulfides(LiPSs) with electrocatalysts has been regarded as an effective avenue to surmount the shuttle effect and realize high-performance lithium–sulfur(Li–S) batteries. However, the complicated reaction process, especially the real-time evolution of sulfur-containing species and electrocatalysts under working conditions, has brought great difficulties in the explicit understanding of reaction mechanism of Li–S batteries, thereby severely hampering the design of highly efficient electrocatalysts. Therefore, a crucial prerequisite for correctly identifying the reaction mechanism is an in-depth analysis of the dynamic evolution of reaction intermediates and their structure-performance relationships. In this review,we comprehensively summarized the most recent progress in the dynamic behaviors of LiPSs and electrocatalysts of Li–S batteries under working conditions in conjunction with closely related in-situ/operando characterizations to recognize the realtime evolution of phase, composition, and atomic/electronic structure, thereby unraveling the corresponding catalytic mechanism. In addition, the major challenges and unexplored issues of catalytic conversion of LiPSs were summarized and discussed, aiming to provide perspectives into the development of highly efficient electrocatalysts in Li–S chemistry. Based on this review, we believe that reasonable regulation of reconstruction behaviors can achieve satisfactory electrocatalysts with high catalytic activity, accelerating the development of green energy.

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双吡唑亚胺镍/甲基铝氧烷催化降冰片烯的聚合

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高等学校化学学报 2008年第8期29卷 1684-1688页

作者：王媛媛祝方明林尚安中山大学化学与化学工程学院高分子科学研究所广州510275

合成了两种双吡唑亚胺镍配合物:双-N-(苯基-1-3,5-二甲基吡唑基亚甲基)苯基亚胺二溴化镍(Cat.1)和双-4-甲氧基-N-(苯基-1-3,5-二甲基吡唑基亚甲基)苯基亚胺二溴化镍(Cat.2).研究了Cat.1/MAO和Cat.2/MAO催化体系对降冰片烯(NBE)单体聚合... 详细信息

合成了两种双吡唑亚胺镍配合物:双-N-(苯基-1-3,5-二甲基吡唑基亚甲基)苯基亚胺二溴化镍(Cat.1)和双-4-甲氧基-N-(苯基-1-3,5-二甲基吡唑基亚甲基)苯基亚胺二溴化镍(Cat.2).研究了Cat.1/MAO和Cat.2/MAO催化体系对降冰片烯(NBE)单体聚合的催化性能,考察了各种聚合条件,如温度、Al/Ni摩尔比及催化剂浓度对降冰片烯的催化效率、单体转化率、聚合物分子量及分子量分布的影响.研究结果表明,Cat.1/MAO和Cat.2/MAO催化体系对降冰片烯聚合具有较高的催化效率,可达到105g PNBE/(molNi)数量级,所得聚降冰片烯(PNBE)的重均分子量在105以上,分子量分布指数在2左右.聚合产物的1H NMR和FTIR谱分析结果表明,该聚合反应是以单体的乙烯基加成聚合机理进行的.

关键词：双吡唑亚胺镍配合物聚降冰片烯聚合乙烯基加成聚合

Individual consistency in spatiotemporal characteristics of migratory Whimbrels in the East Asian-Australasian Flyway

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Avian Research 2024年第3期15卷 308-315页

作者： Siwei An Fenliang Kuang Wei Wu Chris J.Hassell Jonathan T.Coleman Zijing gao Xuena Sun Yue yuan Grace Maglio Kar-Sin K.Leung Xuesong Feng Zhijun Ma Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Coastal Ecosystems Research Station of the Yangtze River EstuaryInstitute of Biodiversity ScienceSchool of Life SciencesFudan UniversityShanghai200433China School of Chemistry and Environment Yunnan Minzu UniversityKunming650504China Shanghai Chongming Dongtan Nature Reserve Administration Center ChongmingShanghai202183China Global Flyway Network PO Box 3089BroomeWA 6725Australia Australasian Wader Studies Group BroomeWA6725Australia Queensland Wader Study Group Shailer ParkQLD4128Australia Hong Kong Waterbirds Ringing Group Hong Kong999077China

Many migratory birds exhibit interannual consistency in migration schedules,routes and stopover *** the interannual consistency in spatiotemporal characteristics helps understand the maintenance of migration and enables the implementation of targeted conservation *** tracked the migration of Whimbrel(Numenius phaeopus)in the East Asian-Australasian Flyway and collected spatiotemporal data from individuals that were tracked for at least two *** non-parametric tests were used to compare the interannual variations in the dates of departure from and arrival at breeding/nonbreeding sites,and the inter-annual variation in the longitudes when the same individual across the same *** exhibited a high degree of consistency in the use of breeding,nonbreeding,and stopover sites between *** variation of arrival dates at nonbreeding sites was significantly larger than that of the departure dates from nonbreeding and breeding *** used stopover sites by the same individuals in multiple years were concentrated in the Yellow Sea coast during northward migration,but were more widespread during southward *** stopover duration at repeatedly used sites was significantly longer than that at sites used only *** flying across the Yellow Sea,Whimbrels breeding in Sakha(Yakutia)exhibited the highest consistency in migration routes in both autumn and ***,the consistency in migration routes of Yakutia breeding birds was generally higher than that of birds breeding in *** results suggest that the northward migration schedule of the Whimbrels is mainly controlled by endogenous factors,while the southward migration schedule is less affected by endogenous *** repeated use of stopover sites in the Yellow Sea coast suggests this region is important for the migration of Whimbrel,and thus has high conservation value.

关键词： Consistency Migration route Migration timing Shorebird