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汕头市礐石花岗岩地貌特征及其成因

热带地理 2024年第3期44卷 403-414页

作者：邱明昆王为温小浩陈敏王晨冯静华南师范大学地理科学学院广州510623 西藏大学生态环境学院拉萨850000 深圳职业技术学院建筑工程学院广东深圳518055

以广东汕头礐石地区景区内各类花岗岩地貌为研究对象,利用地表调查和洞穴调查,在国内外已有研究的基础上,对礐石地区花岗岩的地貌特征、成因及形成年代进行探讨。结果表明:礐石山由燕山晚期花岗岩构成,于中更新世晚期之前就受风化作用;... 详细信息

以广东汕头礐石地区景区内各类花岗岩地貌为研究对象,利用地表调查和洞穴调查,在国内外已有研究的基础上,对礐石地区花岗岩的地貌特征、成因及形成年代进行探讨。结果表明:礐石山由燕山晚期花岗岩构成,于中更新世晚期之前就受风化作用;礐石花岗岩石节理的性质和礐石地区高温多雨的热带季风气候下产生的风化作用,是形成礐石花岗岩地貌的基本因素;礐石地区花岗岩山体主要分为石蛋山、峰林山、馒头山3种类型;洞穴可划分石核洞,崩塌洞穴,裂隙洞和龛4类。

关键词：花岗岩地貌控制因素形成年代石蛋山礐石汕头

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Pruning method for dendritic neuron model based on dendrite layer significance constraints

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CAAI Transactions on Intelligence Technology 2023年第2期8卷 308-318页

作者： Xudong Luo xiaohao wen Yan Li Quanfu Li Key Lab of Education Blockchain and Intelligent Technology Ministry of EducationGuangxi Normal UniversityGuilinChina Guangxi Key Lab of Multi‐Source Information Mining and Security Guangxi Normal UniversityGuilinChina Teachers College for Vocational and Technical Education Guangxi Normal UniversityGuilinChina Electrical and Computer Engineering New Jersey Institute of TechnologyNewarkNew JerseryUSA College of Electronic Engineering Guangxi Normal UniversityGuilinChina

The dendritic neural model(DNM)mimics the non-linearity of synapses in the human brain to simulate the information processing mechanisms and procedures of *** enhances the understanding of biological nervous systems and the applicability of the model in various ***,the existing DNM suffers from high complexity and limited generalisation *** address these issues,a DNM pruning method with dendrite layer significance constraints is *** method not only evaluates the significance of dendrite layers but also allocates the significance of a few dendrite layers in the trained model to a few dendrite layers,allowing the removal of low-significance dendrite *** simulation experiments on six UCI datasets demonstrate that our method surpasses existing pruning methods in terms of network size and generalisation performance.

关键词： compression computational intelligence deep learning neural network machine learning

海南岛文昌现代红色沙质土壤的主量元素分析结果与意义

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佛山科学技术学院学报（自然科学版） 2024年第1期42卷 52-57页

作者：陈敏李保生王丰年牛东风温小浩华南师范大学地理科学学院广东广州510631 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室陕西西安710061 惠州学院地理与旅游学院广东惠州516007 岭南师范学院地理科学学院广东湛江524048

对海南岛东北部文昌坑尾园风成砂物质基础上发育的现代“红色沙壤”中SiO_(2)、Al_(2)O_(3)、TOFE、CaO、Na_(2)O、K_(2)O、MgO这7种主量元素的研究发现:现代红色沙壤土中SiO_(2)含量最高,MgO含量最低;CIA分别与Saf和ba存在负相关关系... 详细信息

对海南岛东北部文昌坑尾园风成砂物质基础上发育的现代“红色沙壤”中SiO_(2)、Al_(2)O_(3)、TOFE、CaO、Na_(2)O、K_(2)O、MgO这7种主量元素的研究发现:现代红色沙壤土中SiO_(2)含量最高,MgO含量最低;CIA分别与Saf和ba存在负相关关系且剖面上下部数据变化符合土壤自剖面底到顶风化程度变弱的规律;坑尾园剖面高CIA值,与该地所处的热湿环境相关。在此环境下,水土流失带来元素迁移,使得除SiO_(2)外的6种元素值均因减少而处于低值状态。

关键词：主量元素红色沙质土壤 CIA Saf ba

Cold events of Holocene indicated by primary elements distribution of the high-resolution sand dunes in the Salawusu River Valley

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Journal of Geographical Sciences 2008年第1期18卷 26-36页

作者： NIU Dongfeng LI Baosheng DU Shuhuan wen xiaohao QIU Shifan OU Xianjiao YANG Yi School of Geography South China Normal University Guangzhou 510631 China State Key Laboratory of Loess and Quatemary Geology Institute of Earth Environment CAS Xi＇an 710061China Baotou Vocational ＆ Technical College Baotou 010022 China

The components of the primary elements in the dune sands for the MGS1 subsection of the Milanggouwan section in the Salawusu River valley, compared with those of modern dune sands, show that they were caused by East Asian winter monsoon in the Mu Us desert during Holocene. The examined ages for the 11 layers of dune sands, based on the average sedimentary rate, are： 0 to 960, 1350-2240, 2470 to 3530, 4000 to 4180, 4290 to 4350, 4380 to 4760, 5040 to 5920, 6570 to 8270, 9020 to 9700, 9880 to 10160 and 10580 to 11080 a BP, respectively. The climatic events indicated by these dune sands are consistent with those records in the Huguangyan volcanic lake, Zoige peat bog, Hulu cave and Dunde ice core, particularly with the climatic fluctuations of the North Atlantic since 11 000 a BP. Among them, patterns from B0 to B8 correspond to the peak values of 0MD, 2D, 4D, 6D＋8D＋10D, 12D, 14D, 16D, 18D and 20D respectively. It might be caused by the North Atlantic ice age induced by the heat circulation, which strengthened the polar high pressure and Siberian-Mongolian high pressure and further led to the dominance of the winter monsoon over China＇s desert area.

关键词： Salawusu River Valley Holocene dune sands primary elements cold events

Grain-size Characteristics and Climate Variability in TMS5e Sequence of Tumen Section in Southern Tengger Desert,Northwestern China

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Chinese Geographical Science 2012年第1期22卷 48-62页

作者： wen xiaohao LI Baosheng WANG Fengnian ZHENG Yanming NIU Dongfeng SI Yuejin OU Xianjiao School of Geographical Science South China Normal University Guangzhou 510631 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇an 710075 China School of Geography and Planning Sun Yat-Sen University Guangzhou 510275 China School of Geography and Tourism Jiaying University Meizhou 514015 China

The TMS5e sequence from the Tumen section,at the southern edge of Tengger Desert in the northwestern China,is synchronous with Marine Isotope Stage 5e(MIS5e).It consists of 16 layers of aeolian dune sands,11 layers of lacustrine loess-like facies,and 5 layers of lacustrine *** results of grain-size analysis shows that the palaeo-mobile dune sands,palaeo-fixed to semi-fixed dune sands and loess-like sandy loams are mainly composed of sands,ranging from 70% to 96%;their silt contents ranged from 4% to 20%,and their clay contents ranged from 1% to 5%;the climate under which the aeolian dune sands were deposited is similar to that under which modern mobile dune sands form,which is caused by the dominance of the cold,dry East Asian winter *** contrast,the lacustrine loess-like facies and lacustrine facies had a lower sand contents than those of the three aeolian dune sands,but have higher silt and clay contents,most of their sand content ranged from 30% to 60%,their silt contents ranged from 35% to 55%,and their clay contents ranged from 6% to 20%.The lacustrine loess-like facies and lacustrine facies formed under the influence of the warm,humid East Asian summer monsoon based on their similarity with modern *** grain-size indicator Mz(mean grain diameter) and the SC/D value in the TMS5e sequence indicate climatic insta-bility at the southern edge of the Tengger Desert during MIS5e,with at least 14 fluctuations between a warm,humid climate and a cold,dry climate,divided into five stages:TMS5e5(139 kyr to 129.3 kyr B.P.),TMS5e4(129.3 kyr to 124 kyr B.P.),TMS5e3(124 kyr to 119.5 kyr B.P.),TMS5e2(119.5 kyr to 116.5 kyr B.P.),and TMS5e1(116.5 kyr to 113.7 kyr B.P.).These correspond roughly to MIS5e5,MIS5e4,MIS5e3,MIS5e2,and MIS5e1,respectively,in the GRIP ice core data.

关键词：腾格里沙漠气候变异中国西北序列图粒度特征江段东亚冬季风湖相沉积

Fucosyltransferase 8 regulates adult neurogenesis and cognition of mice by modulating the Itga6-PI3K/Akt signaling pathway

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Science China(Life Sciences) 2024年第7期67卷 1427-1440页

作者： Hongfeng Guo Qihang Sun Xiaoli Huang xiaohao Wang Feng Zhang wenzheng Qu Jinling Liu Xuejun Cheng Qiang Zhu wen Yi Qiang Shu Xuekun Li The Children’s Hospital National Clinical Research Center for Child HealthSchool of MedicineZhejiang UniversityHangzhou 310052China The Institute of Translational Medicine School of MedicineZhejiang UniversityHangzhou 310029China College of Life Sciences Zhejiang UniversityHangzhou 310058China Binjiang Institute of Zhejiang University Hangzhou 310053China Zhejiang University Cancer Center Zhejiang UniversityHangzhou 310029China

Fucosyltransferase 8(Fut8)and core fucosylation play critical roles in regulating various biological processes,including immune response,signal transduction,proteasomal degradation,and energy ***,the function and underlying mechanism of Fut8 and core fucosylation in regulating adult neurogenesis remains *** have shown that Fut8 and core fucosylation display dynamic features during the differentiation of adult neural stem/progenitor cells(aNSPCs)and postnatal brain ***8 depletion reduces the proliferation of a NSPCs and inhibits neuronal differentiation of aNSPCs in vitro and in vivo,***,Fut8 deficiency impairs learning and memory in ***,Fut8 directly interacts with integrinα6(Itga6),an upstream regulator of the PI3kAkt signaling pathway,and catalyzes core fucosylation of *** of Fut8 enhances the ubiquitination of Itga6 by promoting the binding of ubiquitin ligase Trim21 to *** levels of Itga6 inhibit the activity of the PI3K/Akt signaling ***,the Akt agonist SC79 can rescue neurogenic and behavioral deficits caused by Fut8 *** summary,our study uncovers an essential function of Fut8 and core fucosylation in regulating adult neurogenesis and sheds light on the underlying mechanisms.

关键词： Fut8 adult neural stem/progenitor cells neurogenesis Itga6 PI3K/Akt

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Millennial-centennial Scales Climate Changes of Holocene Indicated by Magnetic Susceptibility of High-resolution Section in Salawusu River Valley, China

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Chinese Geographical Science 2010年第3期20卷 243-251页

作者： LU Yingxia LI Baosheng wen xiaohao QIU Shifan WANG Fengnian NIU Dongfeng LI Zhiwen Geography Department South China Normal University Guangzhou 510631 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi'an 710061 China Guangzhou lnstitute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

The upmost segment (Holocene series) of the Milanggouwan stratigraphic section (MGS1) in the Salawusu River valley shows 11 sedimentary cycles of dune sands and fluvio-lacustrine facies, or dune sands and paleosols. The analysis of the magnetic susceptibility of this segment suggests that there are 11 magnetic susceptibility cycles with the value alternating from low to high, in which the layers of the dune sands correspond to the lower value of the magnetic susceptibility and the layers of fluvio-lacustrine facies and paleosols correspond to the higher peaks. The study reveals that the low and high magnetic susceptibility values indicate the climate dominated by cold-arid winter monsoon and warm-humid summer monsoon of East Asia, respectively, and the study area has experienced at least 22 times of millennial-centennial scales climate alternation from the cold-arid to the warm-humid during the Holocene. In terms of the time and the climate nature, the variations basically correspond to those of the North Atlantic and some records of cold-warm changes in China as well. They might be caused by the alternation of winter and summer monsoons in the Mu Us Desert induced by global climate fluctuations in the Holocene.

关键词：萨拉乌苏河流域气候变化磁化率全新世高分辨率百年尺度中国夏季季风

Phases of Environmental Evolution Indicated by Primary Chemical Elements and Paleontological Records in the Upper Pleistocene-Holocene Series for the Salawusu River Valley,China

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Acta Geologica Sinica(English Edition) 2007年第4期81卷 555-565页

作者： LI Baosheng wen xiaohao QIU Shifan David Dian ZHANG DU Shuhuan CHEN Deniu OU Xianjiao NIU Dongfeng School of Geography South China Normal University Guangzhou Guangdong 510631 State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇an Shaanxi 710061 Department of Geography and Geology the University ofHong Kong Hong Kong Institute of Zoology Chinese Academy of Sciences Beijing 100080

Studies of lithology, sedimentary facies and the distribution regularity of SiO2 and Al2O3 contents and Al2O3/SiO2 ratio allow us to divide the Upper Pleistocene-Holocene Series represented by the MUanggouwan section in China＇s Salawnsu River valley into six segments： MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6. The boundary ages for MGS1 （the Dishaogouwan and Dagouwan Formations）, MGS2 （the upper Chengchuan Formation）, MGS3 （the middle Chengchuan Formation）, MGS4 （the lower Chengchuan Formation）, MGS5 （most strata of the Salawusu Formation） and MGS6 （the bottom of the Salawusu Formation and the top of the Lishi Formation） correspond to those of MIS1, MIS2, MIS3, MIS4, MISS and MIS6, respectively, from deep sea sediments or continental glaciers. MGS5 can be subdivided into five subsegments （MGS5a, MGS5b, MGS5c, MGS5d and MGS5e） and the boundary ages of these subsegments correspond to those of MISSa, MISSb, MIS5c, MIS5d and MIS5e, respectively. Based on the paleoenvironment and paleoecology indicated by the primary chemical elements, fossil vertebrates, mollusks and pollen grains, we hypothesize that MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6 and the subsegments of MGS5 match the corresponding stages for oxygen isotopes in the deep sea sediments and continental glaciers, and the substages of MIS5 in terms of climatic characters, further explaining the phenomena that determined the formation of the late Quaternary strata and the paleontology of the Salawusu River valley. These phenomena relate to fluctuations in the global climate （and particularly in the East Asian monsoon） during the glacial and interglacial periods.

关键词： Salawusu River valley Upper Pleistocene-Holocene Series primary chemical elements,phases of evolution paleontological records

Pleniglacial millennium-scale climate variations in northern China based on records from the Salawusu River Valley

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Journal of Arid Land 2012年第3期4卷 231-240页

作者： FengNian WANG BaoSheng LI JiangLong WANG xiaohao wen DongFeng NIU Zhiwen LI YueJun SI YiHua GUO ShuHuan DU School of Geography South China Normal UniversityGuangzhou 510631China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Chenghai Middle School Shantou 510601China College of Earth Science East China Institute of TechnologyNanchang 330013China Key Laboratory of Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Situated in the Salawusu River Valley, southeast of China＇s Mu Us Desert, the MGS2 （Milanggouwan section） portion of the Milanggouwan stratigraphic section records 5.5 sedimentary cycles consisting of alternations between dune sand deposits and fluvial or lacustrine facies. We analyzed the grain-size and CaCO3 distributions in MGS2, and found that Mz （mean particle diameter） and o （standard deviation） displayed clear variations in peaks and valleys within different sedimentary facies. The CaCO3 content averaged 0.4% in the dune sand deposits, 1.43% in the fluvial facies, and 8.82% in the lacustrine facies. Both the grain-size distribution and CaCO3 contents, which equal the indicators for the alternation among the sedimentary facies, suggest the occurrence of 5.5 cycles. These results suggest that the observed cycles mainly resulted from fluctuations between a cold and dry winter monsoon climate and a warm and humid summer monsoon climate, and that the MGS2 portion experienced at least 5.5 fluctuations between these two extremes. This high-frequency climatic fluctuation indicates a strong influence of millennium-scale variations in the strength of the East Asian winter and summer monsoons in our study area during the Pleniglacial.

关键词： Salawusu River Valley Pleniglacial paleoclimatic indices CaCO3 grain-size