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Acta Geologica Sinica(English Edition) 1992年第4期66卷 411-425,448页

作者： xu Ruisong guangzhou New Technology institute of Geology, Academia Sinica Jiang Minxi guangzhou New Technology institute of Geology Academta Sinica

The vegetation has been poisoned by gold in the western Guangdong-Hainan region. The gold content ofthe leaves there is as high as 10-1961 times the abundance, the chlorophyll content is 10%-30% lower thanthat of the vegetation in metamorphic terrains and 10%-20% higher than that in granite terrains, and thecarotenoid content is 10%-44% lower than the background value. The water content of leaves is 10% to 20%lower than the background value. The cells of leaves are deformed and broken. The leaf surface shows colourspots and becomes yellow or dark green. The spectral reflectance of the leaf surface is 5%-30% higher than thebackground value: the spectral shape has shifted 5-15 nm to the short wavelength. The gray scales of eanopyon images of Landsat TM and airborne imaging scanner (AIS) are 10%-100% higher than the backgroundvalues. On Landsat TM and AIS false colour images, plants poisoned by gold display a yellow color, whichdisinguishes them from background plants. According to the spectral and image features of goldbiogeochemical effects, the author has constructed a gold information system and expert prediction system,and thus two gold target areas and two gold prospect areas have been identified rapidly, economically andaccurately in the western Guangdong-Hainan region which is extensively covered by vegetation.

关键词： biogeochemical effects of gold deposit physiological and ecological characteristics of vegetation characteristics of spectral reflectance characteristics of remote sensing image information and experts system for gold deposit exploration

Unraveling the mysteries of volatile cycling and habitability on Earth and beyond

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National Science Review 2024年第06期11卷 8-9页

作者： Yi-Gang xu Ri-Xiang Zhu Min-Han Dai State Key Laboratory of Isotope geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences State Key Laboratory of Lithosphere Evolution Institute of Geology and Geophysics Chinese Academy of Sciences State Key Laboratory of Marine Environmental Science Xiamen University

The origin and cycling of volatiles, including water, carbon dioxide, and nitrogen, are fundamental to the very existence of habitable planets. These volatile compounds, often taken for granted,are the lifeblood of planetary systems, influencing almost everything from atmospheric composition and climate regulation to deep Earth processes and the emergence of life.

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Changes of tropical cyclone size in three oceanic basins of the northern hemisphere from 2001 to 2021

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Frontiers of Earth Science 2024年第2期18卷 312-323页

作者： Banglin ZHANG Jeremy Cheuk-Hin LEUNG Shengyuan LIU Jianjun xu guangzhou institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction CMAGuangzhou 510640China College of Atmospheric Science Lanzhou UniversityLanzhou 730020China College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiang 524088China CMA-GDOU Joint Laboratory for Marine Meteorology&South china Sea institute of Marine Meteorology Guangdong Ocean UniversityZhanjiang 524088China

In this study the changes of tropical cyclone(TC)size from 2001 to 2021 are analyzed based on linear and quadratic curve fittings of the National Hurricane Center(NHC)/Joint Typhoon Warning Center(JTWC)best track data,based on the radius of maximum wind(RMW)and the average radius of 34-kt wind(AR34),in three oceanic basins of the North Atlantic(NATL),the Western North Pacific(WPAC)and the Eastern North Pacific(EPAC).The computations are done separately for two categories of tropical cyclones:tropical storms(TS)and hurricanes(HT).Size changes of landfalling and non-landfalling TCs are also *** show that there is a great inter-basin variability among the changes in TC *** conclusions include:1)overall,the inner cores of TSs have become larger in all three basins,with the increasing tendencies being significant in the NATL and WAPC,while those of HTs mostly get smaller or remain similar;2)meanwhile,comparatively large inter-basin differences are observed for the TC outer core sizes,and the sizes of landfalling TCs;3)particularly,a significant decrease in landfalling HT outer core size is observed over the EPAC;4)in contrast,significant increases in landfalling TS inner core size are found over the NATL and *** presented analysis results could benefit future research about TC forecasts,storm surge studies,and the cyclone climate and its changes.

关键词： tropical cyclone storm size frequency intensity duration

Identification and effective regulation of scarb1 gene involved in pigmentation change in autotetraploid Carassius auratus

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Zoological Research 2024年第2期45卷 381-397页

作者： Xi-Dan xu Yue Zhou Chong-Qing Wang xu Huang Kun Zhang Xiao-Wei xu Li-Wen He Xin-Yue Zhang Xin-Zhu Fu Ming Ma Qin-Bo Qin Shao-Jun Liu State Key Laboratory of Developmental Biology of Freshwater Fish Engineering Research Center of Polyploid Fish Reproduction and Breeding of the State Education MinistryCollege of Life SciencesHunan Normal UniversityChangshaHunan 410081China Nansha-South china Agricultural University Fishery Research institute GuangzhouGuangdong 511458China Hunan Yuelu Mountain Science and Technology Co.Ltd.for Aquatic Breeding ChangshaHunan 410081China College of Chemistry and Chemical Engineering Hunan Normal UniversityChangshaHunan 410081China

The autotetraploid Carassius auratus(4nRR,4n=200,RRRR)is derived from whole-genome duplication of Carassius auratus red var.(RCC,2n=100,RR).In the current study,we demonstrated that chromatophores and pigment changes directly caused the coloration and variation of 4nRR skin(red in RCC,brownish-yellow in4nRR).To further explore the molecular mechanisms underlying coloration formation and variation in 4nRR,we performed transcriptome profiling and molecular functional verification in RCC and *** revealed that scarb1,associated with carotenoid metabolism,underwent significant down-regulation in *** editing of this candidate pigment gene provided clear evidence of its significant role in RCC ***,we identified four divergent scarb1 homeologs in 4nRR:two original scarb1 homeologs from RCC and two duplicated ***,three of these homeologs possessed two highly conserved alleles,exhibiting biased and allelespecific expression in the ***,after precise editing of both the original and duplicated scarb1homeologs and/or alleles,4nRR individuals,whether singly or multiply mutated,displayed a transition from brownishyellow skin to a cyan-gray ***,the proportional areas of the cyan-gray regions displayed a gene-dose *** findings illustrate the subfunctionalization of duplicated scarb1,with all scarb1genes synergistically and equally contributing to the pigmentation of *** is the first report concerning the functional differentiation of duplicated homeologs in an autopolyploidfish,substantiallyenrichingour understanding of coloration formation and change within this group of organisms.

关键词： Autopolyploidization Coloration change scarb1 Functional differentiation Genetic changes

Decoding the Molecular Mechanisms of BRAFV600E-Induced Nevi Formation

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Biomedical and Environmental sciences 2024年第7期37卷 774-784页

作者： Weizheng Liang Yuxuan Liu Dandan xu Wenjie Jiang Rensen Ran Central Laboratory The First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000HebeiChina institute of Molecular Immunology School of Laboratory Medicine and BiotechnologySouthern Medical UniversityGuangzhou 510515GuangdongChina Department of Artificial Intelligence and Data Science Hebei University of TechnologyTianjin 300401China Department of Chemical Biology School of Life SciencesSouthern University of Science and TechnologyShenzhen 518055GuangdongChina

Melanocytes derived from neural crest cells harbor the BRAFV600E mutation,which is the predominant driver of nevus formation in *** mutation leads to malignant cell proliferation and subsequent cell cycle arrest,culminating in oncogene-induced senescence and nevus ***,emerging evidence has highlighted the heterogeneity of cellular senescence markers in BRAFV600E-induced senescent ***,the capacity of melanocytes within nevi to regain their proliferative ability raises questions about the molecular mechanisms by which BRAFV600E,via the mitogen-activated protein kinase signaling pathway,triggers nevus *** study provides an overview and discussion of the molecular mechanisms underpinning BRAFV600E-induced melanocyte nevus formation and the relevant animal models employed for their *** also highlights the significance of elucidating dynamic changes in cytoplasmic and nuclear substrates that interact with phosphorylated extracellular signal-regulated protein kinases 1 and 2 and underscores the value of using targeted BRAFV600E animal models created through gene editing technologies.

关键词： BRAFV600E Melanocytes Nevi Oncogene-induced senescence Animal models

Policy Network-Based Dual-Agent Deep Reinforcement Learning for Multi-Resource Task Offloading in Multi-Access Edge Cloud Networks

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china Communications 2024年第4期21卷 53-73页

作者： Feng Chuan Zhang xu Han Pengchao Ma Tianchun Gong Xiaoxue School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China institute of Intelligent Communication and Network Security Chongqing University of Posts and TelecommunicationsChongqing 400065China Key Laboratory of Big Data Intelligent Computing Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Information Engineering Guangdong University of TechnologyGuangzhou 510006China

The Multi-access Edge Cloud(MEC) networks extend cloud computing services and capabilities to the edge of the networks. By bringing computation and storage capabilities closer to end-users and connected devices, MEC networks can support a wide range of applications. MEC networks can also leverage various types of resources, including computation resources, network resources, radio resources,and location-based resources, to provide multidimensional resources for intelligent applications in 5/***, tasks generated by users often consist of multiple subtasks that require different types of resources. It is a challenging problem to offload multiresource task requests to the edge cloud aiming at maximizing benefits due to the heterogeneity of resources provided by devices. To address this issue,we mathematically model the task requests with multiple subtasks. Then, the problem of task offloading of multi-resource task requests is proved to be NP-hard. Furthermore, we propose a novel Dual-Agent Deep Reinforcement Learning algorithm with Node First and Link features(NF_L_DA_DRL) based on the policy network, to optimize the benefits generated by offloading multi-resource task requests in MEC networks. Finally, simulation results show that the proposed algorithm can effectively improve the benefit of task offloading with higher resource utilization compared with baseline algorithms.

关键词： benefit maximization deep reinforcement learning multi-access edge cloud task offloading

Generic load regulation strategy for enhancing energy efficiency of chiller plants

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Building Simulation 2024年第8期17卷 1273-1287页

作者： Hang Wan Yuyang Gong Shengwei Wang Yongjun Sun Tao xu Gongsheng Huang Department of Architecture and Civil Engineering City University of Hong KongHong KongChina Department of Building Environment and Energy Engineering Hong Kong Polytechnic UniversityHong KongChina School of Civil Engineering Guangzhou UniversityGuangzhouChina Shenzhen Research institute of City University of Hong Kong ShenzhenChina

In many chiller plants,high coefficient of performance(COP)is only achieved at a few favorable part load ratios(PLRs),while the COP is low at many other non-favorable *** address this issue,this study proposes a generic load regulation strategy that aims to maintain chiller plants operating at high COP,particularly under non-favorable *** is achieved by incorporating thermal energy storage(TES)units and timely optimizing the charging and discharging power of the integrated TES *** optimal charging and discharging power is determined by solving a dynamic optimization problem,taking into account the performance constraints of the TES units and the chiller *** provide an overview of the energy-saving potential of the proposed strategy,a comprehensive analysis was conducted,considering factors such as building load profiles,COP/PLR curves of chillers,and attributes of the TES *** analysis revealed that the proposed load regulation strategy has the potential to achieve energy savings ranging from 5.7%to 10.8%for chiller plants with poor COPs under unfavorable PLRs,particularly in buildings with significant load variations.

关键词： load regulation thermal energy storage chiller plants building energy efficiency

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微囊蛋白基因及其与疾病关系研究进展

生物化学与生物物理进展 2003年第3期30卷 375-378页

作者：梁旭方黄芬暨南大学生物工程学系广州510632 中国科学院生物物理研究所生物大分子国家重点实验室北京100101

微囊蛋白 (caveolin)基因家族已鉴定出 3个成员 :微囊蛋白 1、微囊蛋白 2、微囊蛋白 3 ,并被定位于抑癌基因位点区域 .微囊蛋白 1是细胞质膜微囊的标记蛋白 ,其中间疏水区域在细胞膜内形成发夹结构 ,并使其N端区域与C端区域在细胞膜内... 详细信息

微囊蛋白 (caveolin)基因家族已鉴定出 3个成员 :微囊蛋白 1、微囊蛋白 2、微囊蛋白 3 ,并被定位于抑癌基因位点区域 .微囊蛋白 1是细胞质膜微囊的标记蛋白 ,其中间疏水区域在细胞膜内形成发夹结构 ,并使其N端区域与C端区域在细胞膜内表面聚合形成支架结构 .微囊蛋白 1与微囊蛋白 2以组成异源寡聚体的形式存在 ,在脂肪细胞、内皮细胞和成纤维细胞中表达最丰富 ,微囊蛋白 3则特异表达于肌肉 .离体与活体研究结果均表明微囊蛋白 1可能具有抑癌功能 ,并可能在细胞信号传导中起刹车作用 .微囊蛋白 1基因敲除小鼠心血管NO与Ca2 +信号途径受损、功能异常 ,肺泡上皮细胞出现异常扩增 ,脂质代谢失衡 ,身体消瘦 .微囊蛋白 2基因敲除小鼠肺功能与耐力均严重受损 ,与微囊蛋白 1基因敲除小鼠的表型非常相似 .微囊蛋白 3为维持心脏正常功能所必需。

关键词：微囊蛋白基因疾病信号转导生物膜细胞质膜微囊

Spectral absorption coefficient of phytoplankton and its relation to chlorophyll a and remote sensing reflectance in coastal waters of southern china

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Progress in Natural Science:Materials International 2005年第4期 55-63页

作者： CAO Wenxi*, YANG Yuezhong, LIU Sheng, xu Xiaoqiang, YANG Dingtian and ZHANG Jianlin(LED Laboratory, South china Sea institute of Oceanology, chinese academy of sciences, guangzhou 510301, china) LED Laboratory South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

The spectral absorption coefficient of phytoplankton in coastal waters of southern china is investigated. Large variations in the absorption coefficient of phytoplankton are found. The absorption coefficient of phytoplankton at 443 nm ranged from 0.006 m -1 to 0.484 m -1 , with an average value of 0.067 m -1 . The chlorophyll specific absorption coefficient of phytoplankton is also a bio optical variable, with a spectrally averaged value of 0.025 m 2·mg -1 . The variations of chlorophyll specific absorption coefficient are mainly attributed to pigment composition of phytoplankton and package effect. The chlorophyll specific absorption coefficient of phytoplankton decreases with the increasing of chlorophyll a concentration. This relationship can be described by a power law function, with the parameters and the coefficient of determination r 2 as functions of wavelength,but the parameters describing the relationships in present study differed from that in Case 1 waters, thus the regional adjustment of model parameters was of particular significance for improving the accuracy of bio optical algorithms for estimation of Chl a concentration and primary production from remotely sensed data. Regression analysis of reflectance ( R rs ) ratio and absorption coefficient of phytoplankton ( a ph ) indicates a close correlation between them, which means that it is possible to retrieve absorption coefficient of phytoplankton using ocean color remote sensing data in optically complex coastal waters.

关键词： absorption coefficient phytoplankton chlorophyll remote sensing bio-optical model coastal waters.

Embryonic stem cells generated by nuclear transfer of human somatic nuclei into rabbit oocytes

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Cell Research 2003年第4期13卷 251-263页

作者： YING CHEN, ZHI xu HE, AILIAN LIU, KAI WANG, WEN WEI MAO, JIAN XIN CHU, YONG LU, ZHENG Fu FANG, YING TANG SHI, QING ZHANG YANG, DA YUAN CHEN, MIN RANG WANG, JIN SONG LI, SHAO LIANG HUANG, XIANG YIN KONG, YAO ZHOU SHI, Zm QIANG WANG, JIA HuI XIA, ZHI GAO LONG, ZHI GANG xuE, WEN XIANG DING, HuI ZHEN SHENG Center for Developmental Biology, Shanghai Second Medical University, Shanghai 200092, china Laboratory of Stem Cell Biology, institute of Biochemistry and Cell Biology, Shanghai institutes for Biological sciences, chinese academy of sciences, 1665 Kong Jiang Road, Shanghai 200092, china Center for Stem Cell Research, the Second Affiliated Hospital, Sun Yat-Sen University, guangzhou 510120,china State Key Laboratory of Reproductive Biology, institute of Zoology, chinese academy of sciences, 19 Zhong-guan Cun Road, Haidian District, Beijing 100080, china Health Science Center, Shanghai institutes of Biological sciences, chinese academy of sciences and Shanghai Second Medical University, Shanghai 200025, china National Laboratory of Medical Genetics, Central South University, 88 Xiangya Road, Changsha 410078, china Xinhua Hospital, Shanghai Second Medical University, 1665 Kong Jiang Road, Shanghai 200092, china 2Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 3Center for Stem Cell Research the Second Affiliated Hospital Sun Yat-Sen University Guangzhou 510120 China. 2Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 4State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences 19 Zhong-guan Cun Road Haidian District Beijing 10008

To solve the problem of immune incompatibility, nuclear transplantation has been envisaged as a means to produce cells or tissues for human autologous transplantation. Here we have derived embryonic stem cells by the transfer of human somatic nuclei into rabbit oocytes. The number of blastocysts that developed from the fused nuclear transfer was comparable among nuclear donors at ages of 5, 42, 52 and 60 years, and nuclear transfer (NT) embryonic stem cells (ntES cells) were subsequently derived from each of the four age groups. These results suggest that human somatic nuclei can form ntES cells independent of the age of the donor. The derived ntES cells are human based on karyotype, isogenicity, in situ hybridization, PCR and immunocytochemistry with probes that distinguish between the various species. The ntES cells maintain the capability of sustained growth in an undifferentiated state, and form embryoid bodies, which, on further induction, give rise to cell types such as neuron and muscle, as well

关键词： nuclear transfer (NT) somatic cell nuclear transfer (SCNT) embryonic stem cells (ES cell) therapeutic cloning rabbit oocyte.