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82篇 您的检索式:作者名="Liu Zhifei"
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1Clay minerals in surface sediments of the Pearl River drainage basin and their contribution to the South China Sea显示文摘Clay minerals have played a significant role in the study of the East Asian monsoon evolution in the South China Sea by being able to track oceanic current variations and to reveal contemporaneous pa- leoclimatic changes prevailing in continental source areas.As one of the most important rivers input- ting terrigenous matters to the northern South China Sea,the Pearl River was not previously paid at- tention to from the viewpoint of clay mineralogy.This paper presents a detailed study on clay minerals in surface sediments collected from the Pearl River drainage basin(including all three main channels, various branches,and the Lingdingyang in the estuary)by using the X-ray diffraction(XRD)method. The results indicate that the clay mineral assemblage consists dominantly of kaolinite(35%-65%), lesser abundance of chlorite(20%-35%)and illite(12%-42%),and very scare smectite occurrences (generally<5%).Their respective distribution does not present any obvious difference throughout the Pearl River drainage basin.However,downstream the Pearl River to the northern South China Sea,the clay mineral assemblage varies significantly:kaolinite decreases gradually,smectite and illite increase gradually.Additionally,illite chemistry index steps down and illite crystallinity steps up.These varia- tions indicate the contribution of major kaolinite,lesser illite and chlorite,and very scarce smectite to the northern South China Sea from the Pearl River drainage basin.The maximum contribution of clay minerals from the Pearl River is 72%to the northern margin and only 15%to the northern slope of the South China Sea.In both glacials and interglacials,kaolinite indicates that the ability of mechanical erosion occurred in the Pearl River drainage basin.LIU ZhiFei Christophe COLIN HUANG Wei CHEN Zhong Alain TRENTESAUX CHEN JianFang 2007Chinese Science Bulletin2007,52,8:33
2Study on the functional changes of BK_(Ca) channels in human vascular smooth muscle cells from Han Chinese patients with hypertension显示文摘Chronic hypertension is associated with an impaired vascular relaxation due to an increased vascular tone.However,the underlying mechanisms are not fully understood in human patients.The present study was to inves-tigate whether large conductance Ca2+-and voltage-activated K+(BKCa)channels are involved inYang Yan Li Pengyun Cheng Jun Mao Liang Wen Jing Tan Xiaoqiu Liu Zhifei Zeng Xiaorong 2013泸州医学院学报2013,36,3:31
3Sedimentary Record of the Planation Surface in the Hoh Xil Region of the Northern Tibet Plateau显示文摘Miocene marl is the most widespread Tertiary stratigraphic record in the northern Tibet Plateau, termed the Wudaoliang Group in the Hoh Xil region and the correlative Suonahu Formation in the Qiangtang region. The uniform marl overlies red beds of the Eocene-Oligocene Fenghuoshan Group. The Wudaoliang Group is generally 100-400 m thick, but the thickest strata are 700-1300 m, located in the Haidinghu (Maiding Lake) and Tuotuohe (Tuotuo River) regions respectively. Based on observations from eight measured sections and outcrops, the thin-bedded marl, which varies in colour from grey-white to light brown-grey, is explained as a large-scale or serial lacustrine deposit stretching throughout northern Tibet.The Wudaoliang Group commonly crops out on geographic lowland at an average elevation of 4600 m above sea level within the mountain chains, showing concordant summit levels, e.g. the Fenghuoshan and Bairizhajia Mountains. These mountains with a flat ridge are considered to be remains of theYI Haisheng WANG Chengshan LIU Shun LIU Zhifei WANG Shifeng 2000Acta Geologica Sinica(English Edition)2000,74,4:22
4A high-resolution clay mineralogical record in the northern South China Sea since the Last Glacial Maximum,and its time series provenance analysis显示文摘High-resolution clay mineralogical analysis of Core MD05-2904 in the northern South China Sea(SCS) covering the period since the Last Glacial Maximum shows that illite(29%-48%),smectite(14%-45%),chlorite(17%-28%),and minor kaolinite(6%-14%) comprise the clay mineral assemblage,and that time series variation does not present glacial-interglacial cyclicity.Provenance analysis indicates three end-member sources:almost all smectite derives from Luzon,all kaolinite is sourced from the Pearl River,and illite and chlorite originate from both the Pearl River and Taiwan.By comparing clay mineral compositions in surface sediments from the three major source areas and of the SCS,we reconstructed a time series of clay mineral contribution from the major provenances to the northern slope of the SCS using the linear separation method for illite crystallinity.There were three stages of provenance change.(1) During 24.1-17.5 ka BP,contributions from Taiwan and Luzon were similar(30%-40%),while that from the Pearl River was only 25%.(2) During 17.5-14.0 ka BP,the contribution from Luzon decreased rapidly to 20%-25%,while that from Taiwan increased to 35% from an average of 25% at 18 ka BP,and that from the Pearl River increased largely to 40%.(3) During the Holocene,differences in contributions from the three major provenances increased:the contribution from Luzon increased slightly and then remained at 27%-35%,that from Taiwan increased rapidly and then remained at 55%-60%,and that from the Pearl River decreased to 15%.The change in clay mineral contributions from different provenances is influenced mainly by clay mineral production,monsoon rainfall denudation,oceanic current transport,and sea-level change.LIU ZhiFei LI XiaJing COLIN Christophe GE HuangMin 2010Chinese Science Bulletin2010,55,35:20
5Advancing application of mesenchymal stem cell-based bone tissue regeneration显示文摘Reconstruction of bone defects,especially the critical-sized defects,with mechanical integrity to the skeleton is important for a patient's rehabilitation,however,it still remains challenge.Utilizing biomaterials of human origin bone tissue for therapeutic purposes has provided a facilitated approach that closely mimics the critical aspects of natural bone tissue with regard to its properties.However,not only efficacious and safe but also costeffective and convenient are important for regenerative biomaterials to achieve clinical translation and commercial success.Advances in our understanding of regenerative biomaterials and their roles in new bone formation potentially opened a new frontier in the fast-growing field of regenerative medicine.Taking inspiration from the role and multicomponent construction of native extracellular matrix(ECM)for cell accommodation,the ECM-mimicking biomaterials and the naturally decellularized ECM scaffolds were used to create new tissues for bone restoration.On the other hand,with the going deep in understanding of mesenchymal stem cells(MSCs),they have shown great promise to jumpstart and facilitate bone healing even in diseased microenvironments with pharmacology-based endogenous MSCs rescue/mobilization,systemic/local infusion of MSCs for cytotherapy,biomaterials-based approaches,cell-sheets/-aggregates technology and usage of subcellular vesicles of MSCs to achieve scaffolds-free or cell-free delivery system,all of them have been shown can improve MSCsmediated regeneration in preclinical studies and several clinical trials.Here,following an overview discussed autogenous/allogenic and ECM-based bone biomaterials for reconstructive surgery and applications of MSCsmediated bone healing and tissue engineering to further offer principles and effective strategies to optimize MSCs-based bone regeneration.Fengqing Shang Yang Yu Shiyu Liu Leiguo Ming Yongjie Zhang Zhifei Zhou Jiayu Zhao Yan Jin 2021Bioactive Materials2021,6,3:13
6The earliest-known ancestors of Recent Priapulomorpha from the Early Cambrian Chengjiang Lagerstatte显示文摘The taxonomy of an early ancestor of Recent Priapulidae, Xiaoheiqingella peculiaris (= Yunnanpriapulus halteroformis Huang et al., 2004) from the Early Cambrian Chengjiang fossil Lagerst?tte, is revised. Morphological characters comprise a pair of caudal appendages rather than a single appendage flanking the trunk end and a possible urogenital duct found inside the preanal region. An addi- tional extremely rare fossil priapulid worm, Paratubiluchus bicaudatus gen. nov., sp. nov. is also described herein. Its diagnostic characters are: an introvert bearing 25 longitudi- nal rows of scalids, a distinct neck region, no annulus on the oval trunk, and a pair of caudal appendages. The proportion of body parts is similar in size to that of loricate larvae of Recent priapulids and larva-formed Palaeopriapulitidae. Taking account of the features of Xiaoheiqingella, bicaudal appendages are considered to be a synapomorphy of Pri- apulidae and Tubiluchidae. Paratubiluchus gen. nov. is most likely a candidate for the ancestor of the Tubiluchidae; it probably originated from a larva-formed priapulid with 25 rows of scalids, thus representing an intermediate link be- tween the priapulids in mature-form and the priapulids with lorica.HAN Jian SHU Degan ZHANG Zhifei LIU Jianni 2004Chinese Science Bulletin2004,49,17:12
7Late Quaternary glacial cycle and precessional period of clay mineral assemblages in the Western Pacific Warm Pool显示文摘Variability of clay mineral assemblages in the Western Pacific Warm Pool(WPWP) over the past 370 ka shows the prominent glacial-interglacial cyclicity.Smectite(62%-91%) is the dominant clay mineral,with decreased contents during interglacials while increased in glacials.In contrast,variations in chlorite(4%-21%),illite(4%-12%),and kaolinite(2%-10%) share a similar pattern with higher contents during interglacials than glacials,mirroring to that of smectite.The results indicate that the smectite-dominated clay minerals derive mainly from the river detrital inputs of New Guinea.The glacial-interglacial cycle of clay mineral assemblages well correspond to the fluctuation of sea level.When the sea level was low,the river materials can travel more easily across the narrow shelf off the island of New Guinea,inject directly into the subsurface currents flowing westwards,then merge into the Equatorial Undercurrent(EUC),and eventually deposit on the central part of WPWP.Precessional periods of the smectite content indicate the intensity of mechanical erosion in its provenance of New Guinea,responding to the river runoff and precipitation,and this could also be linked to the meridional migration of the Intertropical Convergence Zone(ITCZ).WU JiaWang LIU ZhiFei ZHOU Chao 2012Chinese Science Bulletin2012,57,28:11
8Pediculate Brachiopod Diandongia pista from the Lower Cambrian of South China显示文摘The Chengjiang Lagerstatte has been celebrated for prolific soft-bodied fossils. Based on specimens recentlyexcavated in the Chengjiang Lagerstatte by the Early Life Institute, Northwest University, Diandongiapista Rong, 1974, isdirectly revealed to be a pediculate brachiopod, assigned to the Family Botsfordiidae, as is further confirmed by theexceptionally preserved vascular system including dorsal and ventral mantle canals. These specimens described hereinexhibit some peculiarities, notably the extremely thin and long pedicles, which suggest that Diandongia is epifaunal ratherthan burrowing brachiopod. A study of this group of animals indicates that they may be vital to understand the relationshipbetween the lingulids and the remaining brachiopods, and the character evolution of the early Cambrian brachiopods.ZHANG Zhifei, HAN Jian, ZHANG Xingliang, LIU Jianni and SHU DeganEarly Life Institute and Key Laboratory for Continental Dynamics of the Ministry of Education,Northwest University, Xi’an, Shaanxi 710069 E-mail: zhangelle@sina.com.cn Wang Si’en and Xie Guanglian 2003Acta Geologica Sinica(English Edition)2003,77,3:9
9Fossil Association from the Lower Cambrian Yanjiahe Formation in the Yangtze Gorges Area,Hubei,South China显示文摘摘要:除了以前报导的小壳的石块(SSF ) ,一个宏观的石块集合,包括的丰富的水藻,锥形的管状的石块形式,和可能的印象一放大了后生动物,在西方的湖北省的 Yangtze 峡区域来自更低的寒武纪的 Yanjiahe 形成,华南。可见石块在 thinlaminated siltstone 被保存或泥泞 siltstone 在 815 公里厚的碳酸盐存款之间设置了,浅水里的抑制本地消沉的可能代表的沉积背景在早寒武纪的 Meishucunian 阶段期间焦化站台。宏观的石块协会关于生活的进化提供重要石块证据从对寒武纪的爆炸间隔晚前寒武纪。GUO Junfeng LI Yong HAN Jian ZHANG Xingliang ZHANG Zhifei OU Qiang LIU Jianni SHU Degan Shigenori MARUYAMA Tsuyoshi KOMIYA 2008Acta Geologica Sinica(English Edition)2008,82,6:8
10Turbidite deposition in the southern South China Sea during the last glacial: Evidence from grain-size and major elements records显示文摘High-resolution grain size and major element geochemical measurements were performed on the marine sediments of Core MD05-2895 to help understand the formation of turbidite sequences. Grain-size results show that these turbidite sediments contain more coarse sediment grains than normal marls. The coarse sediment grains are mostly derived from relict sediments on the Sunda Shelf. Relict sediments are composed mainly of quartz, feldspar, tephra and a few titaniferous or ferruginous heavy minerals. Corresponding to the concentration of these minerals, increases in Si/Al, K/Al, Ti/Al and Fe/Al ratios are observed in the turbidite layers. As all the observed turbidite sequences were deposited during the last glacial, the occurrence of these turbidity events is implied to be closely related to instabilities in sea-level-induced sediment supply. We suggest that deposition of sediment particles from a single turbidity current is usually controlled by a counterbalance between gravity and buoyancy, with the interaction of individual grains being of minor importance.ZHAO YuLong LIU ZhiFei COLIN Christophe XIE Xin WU Qiong 2011Chinese Science Bulletin2011,56,33:7
11Simultaneous incorporation of PTH(1-34) and nano-hydroxyapatite into Chitosan/Alginate Hydrogels for efficient bone regeneration显示文摘Tissue regeneration based on the utilization of artificial soft materials is considered a promising treatment for bone-related diseases.Here,we report cranial bone regeneration promoted by hydrogels that contain parathyroid hormone(PTH)peptide PTH(1-34)and nano-hydroxyapatite(nHAP).A combination of the positively charged natural polymer chitosan(CS)and negatively charged sodium alginate led to the formation of hydrogels with porous structures,as shown by scanning electron microscopy.Rheological characterizations revealed that the mechanical properties of the hydrogels were almost maintained upon the addition of nHAP and PTH(1-34).In vitro experiments showed that the hydrogel containing nHAP and PTH(1-34)exhibited strong biocompatibility and facilitated osteogenic differentiation of rat bone marrow mesenchymal stem cells(rBMSCs)via the Notch signaling pathway,as shown by the upregulated expression of osteogenic-related proteins.We found that increasing the content of PTH(1-34)in the hydrogels resulted in enhanced osteogenic differentiation of BMSCs.Implantation of the complex hydrogel into a rat cranial defect model led to efficient bone regeneration compared to the rats treated with the hydrogel alone or with nHAP,indicating the simultaneous therapeutic effect of nHAP and PTH during the treatment process.Both the in vitro and in vivo results demonstrated that simultaneously incorporating nHAP and PTH into hydrogels shows promise for bone regeneration,suggesting a new strategy for tissue engineering and regeneration in the future.Zhiyuan Zou Le Wang Zhifei Zhou Qing Sun Delong Liu Yan Chen Hao Hu Yu Cai Sixiong Lin Zhengran Yu Bizhi Tan Wei Guo Zemin Ling Xuenong Zou 2021Bioactive Materials2021,6,6:7
12Preliminary notes on soft-bodied fossil concentrations from the Early Cambrian Chengjiang deposits显示文摘The efforts of labor-intensive collecting in the Early Cambrian Chengjiang deposits in eastern Yunnan Province, China led to the discovery of many horizons containing exceptionally well preserved soft-bodied fossil concentrations, many of which can be assigned to either monospecific concentrations or paucispecific concentrations. The features of these fossil concentrations support the hypothesis that frequent storm events producing tempestites mainly contributed to the preservation of abundant soft- bodied fossils in the Chengjiang deposits, and indi- cate that the balance of the ecological web in this region was probably frequently destroyed or upset by such storm events during that geological time. Ani- mals in a fossil assemblage in such fossil concentra- tions probably occupied similar ecological biotopes.HAN Jian SHU Degan ZHANG Zhifei LIU Jianni ZHANG Xingliang YAO Yang 2006Chinese Science Bulletin2006,51,20:6
13New observations of the lobopod-like worm Facivermis from the Early Cambrian Chengjiang Lagerstatte显示文摘Facivermis yunnanicus (Hou & Chen, 1989), from the Early Cambrian Chengjiang Lager- st?tte, a worm-like fossil with 5 pairs of tentacles and a perceived shrunken end, has been regarded as related to polychaetes, later it has been variously interpreted as lobopods, Pentastoma and lopho- phorates. Newly discovered complete specimens by the ELI field team show that the taxon has, in addition to the 5 pairs of appendages, a pear-shaped trunk end bearing two or three circles of hooks. Accordingly, based on these important morphological characters, reconsideration of its affinities is provided and the taxonomy is remedied herein. Because the five pairs of appendages of Facivermis yunnanicus resemble the appendages of the fore-trunk of lobopod Mi- raluolishania (Liu & Shu, 2004), it seems that they are homologous structures. Therefore, the affinities of Facivermis are regarded here as being close to the lobopods, in addition, the lobe-like appendages of Facivermis are very crucial to exploring the origin of the appendages of lobopods and arthropods.LIU Jianni HAN Jian SIMONETTAA. M. HU Shixue ZHANG Zhifei YAO Yang SHU Degan 2006Chinese Science Bulletin2006,51,3:5
14Spatiotemporal variations of deep-sea sediment components and their fluxes since the last glaciation in the northern South China Sea显示文摘Sediment components and their fluxes of Cores MD12-3428(water depth: 903 m), MD12-3433(water depth: 2125 m),and MD12-3434(water depth: 2995 m), obtained along a transect on the continental slope of the northern South China Sea, have been conducted to reveal the spatiotemporal variations and the controlling factors of the sediment components and of their fluxes.Results show that deep-sea sediments in the northern South China Sea are composed mainly of terrigenous(59–89%) and carbonate(6–38%) particles, with minor components of opal(1.6–9.4%) and organic matter(0.7–1.9%). Fluxes of terrigenous and carbonate particles reach up to 2.4–21.8 and 0.4–6.5 g cm–2 kyr–1, respectively, values that are one to two orders of magnitude higher than the fluxes of opal and organic matter. Temporal variations of the percentages and fluxes of deep-sea sediment components have displayed clear glacial-interglacial cyclicity since the last glaciation. Terrigenous, opal, and organic matter percentages and their fluxes increas clearly during marine isotope stage 2, while carbonate percentages and fluxes show an opposite variation pattern or are characterized by an unremarkable increase. This implies that deep-sea carbonate in the South China Sea is affected by the dilution of terrigenous inputs during the sea-level lowstand. With increasing water depth along the transect, the terrigenous percentage increases but with largely decreased fluxes. Both the percentage and flux of carbonate decrease, while the percentages and fluxes of opal and organic matter display much more complicated variational features. The spatiotemporal variations of deep-sea sediment components and of their fluxes since the last glaciation in the northern South China Sea are strongly controlled by sea-level fluctuations. Simultaneously, terrigenous supply associated with monsoonal rainfall, marine primary productivity,and the dilution effect between terrigenous and biogenic particles, also play interconnected roles in the sediment accumulation processes.ZHAO ShaoHua LIU ZhiFei CHEN Quan WANG XingXing SHI JiangNan JIN HaiYan LIU JingJing JIAN ZhiMin 2017Science China Earth Sciences2017,60,7:5
15ICG@ZIF-8:One-step encapsulation of indocyanine green in ZIF-8 and use as a therapeutic nanoplatform显示文摘How to fabricate zeolitic imidazole framework-8(ZIF-8) based therapeutic nanoplatform will be of significance in biomedicine considering its good biocompatibility. Herein, we report a one-step encapsulation of indocyanine green(ICG) in ZIF-8 nanoparticles(NPs). The as-prepared ICG@ZIF-8 NPs possess an absorption band in the near infrared region and have the good photothermal conversion efficiency. The in vivo and in vitro studies show that, after loading chemotherapy agent hydrophobic doxorubicin(DOX), ICG@ZIF-8-DOX NPs exhibit the chem-and photothermal synergistic therapy for tumor. In addition, it is found that the embedded ICG molecules in ICG@ZIF-8 NPs can be disassociated and released into the solution upon the 808 nm laser irradiation, demonstrating that as-prepared ICG@ZIF-8 NPs can also be used as the optical imaging probe to trace the degradability behavior of resulting NPs inChao Yang Jing Xu Dandan Yang Xiaoxiao Wang Bin Liu Nongyue He Zhifei Wang 2018Chinese Chemical Letters2018,29,9:5
16Are hyoliths Palaeozoic lophophorates?显示文摘The phylogenetic position of hyoliths has long been unsettled,with recent discoveries of a tentaculate feeding apparatus('lophophore')and fleshy apical extensions from the shell('pedicle')suggesting a lophophorate affinity.Here,we describe the first soft parts associated with the feeding apparatus of an orthothecid hyolith,Triplicatella opimus from the Chengjiang biota of South China.The tuft-like arrangement of the tentacles of T.opimus differs from that of hyolithids:suggesting they collected food directly from the substrate.A reassessment of the feeding organ in hyolithids indicates that it does not represent a lophophore and our analysis of the apical structures associated with some orthothecids show that these represent crushed portions of the shell and are not comparable to the brachiopod pedicle.The new information suggests that hyoliths are more likely to be basal members of the lophotrochozoans rather than lophophorates closely linked with the Phylum Brachiopoda.Fan Liu Christian B Skovsted Timothy P Topper Zhifei Zhang Degan Shu 2020National Science Review2020,7,2:5
17GOLM1 exacerbates CD8^(+)T cell suppression in hepatocellular carcinoma by promoting exosomal PD-L1 transport into tumor-associated macrophages显示文摘The immunosuppressive microenvironment plays an important role in tumor progression and immunotherapy responses.Golgi membrane protein 1(GOLM1)is correlated to hepatocellular carcinoma(HCC)progression and metastasis.However,little is known about the role of GOLM1 in regulating the immunosuppressive environment and its impact on immunotherapeutic efficacy in HCC.In this study,GOLM1 was positively correlated with infiltrating tumor-associated macrophages(TAMs)expressed high levels of programmed death-ligand 1(PD-L1)and CD8^(+)T cell suppression in HCC tissues.Both gain-and loss-of-function studies determined a close correlation between GOLM1 and immunosuppression.In the mechanism,GOLM1 promoted COP9 signalosome 5-mediated PD-L1 deubiquitination in HCC cells and increased the transport of PD-L1 into exosomes via suppression of Rab27b expression.Furthermore,co-culture with exosomes derived from HCC cells upregulated the expression of PD-L1 on macrophages.Zoledronic acid in combination with anti-PD-L1 therapy reduced PD-L1^(+)TAMs infiltration and alleviated CD8^(+)T cell suppression,resulting in tumor growth inhibition in the mouse HCC model.Together,our study unveils a mechanism by which GOLM1 induces CD8^(+)T cells suppression through promoting PD-L1 stabilization and transporting PD-L1 into TAMs with exosome dependent.Targeting PD-L1^(+)TAM could be a novel strategy to enhance the efficacy of anti-PD-L1 therapy in HCC.Jinhong Chen Zhifei Lin Lu Liu Rui Zhang Yan Geng Minghao Fan Wenwei Zhu Ming Lu Lu Lu Huliang Jia Jubo Zhang Lun-Xiu Qin 2021Signal Transduction and Targeted Therapy2021,6,12:5
18Calcium carbonate pump during Quaternary glacial cycles in the South China Sea显示文摘The preservation and dissolution of calcium carbonate (namely calcium carbonate pump) controls the pH of seawater in global oceans by its buffer effect, and in turn plays a significant role in global changes in atmospheric CO2 concentration. The results from measured carbonate con-tents over the past 2 Ma at ODP Site 1143 in the South China Sea provide high-resolution records to explore the process of the calcium carbonate pump during Quaternary glacial cy-cles. The results indicate statistically that the highest car-bonate accumulation rate leads the lightest d 18O by about 3.6 ka at transitions from glacials to interglacials, and that the strongest carbonate dissolution lags the lightest d 18O by about 5.6 ka at transitions from interglacials to glacials. The calcium carbonate pump releases CO2 to the atmosphere at the glacial-interglacial transitions, but transports atmos-pheric CO2 to deep sea at the interglacial-glacial transitions. The adjustable function of the calcium carbonate pump for the deep-sea 23CO- concentration directly controls parts of global changes in atmospheric CO2, and contributes the global carbon cycle system during the Quaternary.LIU Zhifei, XU Jian, TIAN Jun & WANG Pinxian Laboratory of Marine Geology, Tongji University, Shanghai 200092, China 2003Chinese Science Bulletin2003,48,17:5
19First report on Guanshan Biota(Cambrian Stage 4) at the stratotype area of Wulongqing Formation in Malong County, Eastern Yunnan, China显示文摘Exceptionally preserved fossils,such as those from Cambrian Burgess Shale-type fossil-Lagerstatten are critical because of their unique contributions to knowledge of the phylogenetic radiation and palaeoecological expansion of metazoans during the Cambrian explosion.Critically,these deposits provide information that is usually unobtainable from shelly and skeletonized fossils alone.The Guanshan Biota(Cambrian Series 2,Stage 4)in the Yunnan Province of South China,has produced abundant and diverse,exquisitely preserved fossils that often retain soft tissues and organs.To date,most fossils from the Guanshan Biota have been collected from localities such as Gaoloufang and Gangtoucun,which have become inaccessible due to new urban expansions and constructions of residential buildings.Here we present the first report of soft bodied fossils from a new section at Kanfuqing,close to the Wulongqing village in Malong County,approximately 3 km east of the Wulongqing Formation stratotype section.Fossils retain soft morphology,and include brachiopods with delicate marginal setae,priapulids with well-preserved sclerites and vetulicolians with entire sections of body.In addition,this fauna includes rare occurrences of trilobites preserved with soft tissues replicated as pyrite pseudomorphs after weathering.This discovery represents an important palaeogeographical extension of soft-bodied fossils of the Guanshan fauna to the east of the Xiaojiang Fault(related to Tsinning tectonic movements ca.700 Ma).The fauna from the new Kanfuqing section is similar to that reported from the Wulongqing Formation west of the Xiaojiang Fault,and thus has significant implications for early Cambrian palaeogeography,faunal successions and palaeoenvironments of eastern Yunnan.Feiyang Chen Zhifei Zhang Marissa J. Betts Zhiliang Zhang Fan Liu 2019Geoscience Frontiers2019,10,4:4
20An improved Landsat Image Mosaic of Antarctica显示文摘A revised Landsat Image Mosaic of Antarctica (LIMA) is presented, using the 1073 multi-band scenes of the original Landsat-7 ETM+ LIMA image collection available at the United States Geological Survey (USGS: http://lima.usgs.gov/). Three improvements have been applied during the data processing: (1) DN saturation is adjusted by adopting a linear regression, which has a lower root mean square error than the ratio regression used by LIMA; (2) solar elevation angle is calculated using pixel-level latitude/longitude and the acquisition time and date of the central pixel of the scene, improving slightly upon the bilinear interpolation of the solar elevation angles of scene corners applied in LIMA; and (3) two additional image bands, Band 5 and Band 7, are sharpened using the panchromatic band (Band 8) and a Gram-Schmidt Spectral Sharpening algorithm to more easily distinguish snow, cloud and exposed rocks. The final planetary reflectance product is stored in 16-bit bands to preserve the full radiometric content of the scenes. A comparative statistical analysis among 12 sample regions indicates that the new mosaic has enhanced visual qualities, information entropy, and information content for land cover classification relative to LIMA.HUI FengMing CHENG Xiao LIU Yan ZHANG YanMei YE YuFang WANG XianWei LI Zhan WANG Kun ZHAN ZhiFei GUO JianHong HUANG HuaBing LI XiuHong GUO ZiQi GONG Peng 2013Science China Earth Sciences2013,56,1:4
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