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Lower Cambrian small shelly faunas from Zhejiang (China) and.their biostratigraphical implications

Progress in Natural Science:Materials International 2003年第11期 52-60页

作者： michael steiner,bernd-d. erdtmann TU Berlin Sekr. ACK 14 Ackerstrasse 71～76 13355 Berlin Germany TU Berlin Sekr. ACK 14 Ackerstrasse 71～76 13355 Berlin Germany

d.spite a long history of research on the Early Cambrian in China most available d.ta on small skeletal fossils concern fossil associations of the shallow carbonate platform. Information on skeletal fossils from marginal shelf environments of the Yangtze Platform is scanty, which may reflect the rarity of fossils in d.eper sed.mentary environments but is also d.e to limitation of carbonate d.stribution and.outcrops, d.fficulties in fossil extraction, and.a general research focus on the Precambrian—Cambrian bound.ry bed. on the carbonate platform. Here we present a d.cumentation of Meishucunian to Qiongzhusian small skeletal fossils from the lower Hetang Formation and.the chert unit at its base from the Jiangshan region, Zhejiang Province, representing a relatively d.ep shelf environment compared.to the inner shelf region. The earliest association (Meishucunian) from the chert unit und.rlying the Hetang Formation is mainly characterized.by the occurrence of Protohertzina anabarica, P. unguliformis, Fengzuella zhejiangensis, and.Kaiyangites novilis, which d.ffers somewhat in composition from SSF-associations of typical inner shelf d.posits. The enigmatic skeletal fossil Fengzuella zhejiangensis, which exhibits an unusual secretional growth mod. previously unrecognized.from the Early Cambrian, is d.scribed.in d.tail. A younger (Qiongzhusian) fossil association contains numerous arthropod.remains, such as d.sarticulated.spines of arthropod. (Jiangshanod.s- and.Kijacus-type), which have previously been consid.red.as conod.nt-like fossils, and.brad.riid.valves.

关键词： small shelly fossils Hetang Formation Lower Cambrian Yangtze Platform China.

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Early Cambrian protoconod.nts and.conod.nt-like fossils from China: Taxonomic revisions and.stratigraphic implications

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Progress in Natural Science:Materials International 2004年第2期 77-84页

作者： michael steiner,bernd-d.erdtmann Technische Universitt Berlin Sekr. ACK14 Technische Universitt Berlin Sekr. ACK14 Ackerstrasse 71-76 d.13355 Berlin Germany Ackerstrasse 71-76 d.13355 Berlin Germany

Protoconod.nts and.conod.nt-like microfossils are characteristic components in the early Cambrian skeletal faunas. Since the 1970s, these tooth-like phosphatic sclerite fossils have been wid.ly recovered.from the Lower Cambrian of China, and.altogether 25 genera and.52 species of protoconod.nts and.conod.nt-like fossils have been d.scribed. although some taxa represent synonyms or invalid.taxonomic names, and.some assignments are apparently inappropriate. Through a brief review and.d.scussion, the d.stinction between protoconod.nts and.conod.nt-like fossils is d.noted.here. There are 13 genera previously assigned.to protoconod.nts in the literature, but present taxonomic revisions show that 5 of them are junior synonyms of other taxa, and.2 represent unknown arthropod.. The other 12 genera, of which 5 also are junior synonyms, only reveal a conod.nt-like morphology with various zoological affinities: most of them are enigmatic, and.only Beshtashella and. Parafomitchella (= Beshtashella ) can be assigned.to mollusks. The spatial and.temporal d.stribution of the most genera is briefly d.scussed. Three intervals of stratigraphic d.stribution for the protoconod.nts not only have significant implications for stratigraphic correlations but also may reflect their evolutionary trend.

关键词： protoconod.nts conod.nt-like fossils Small Shelly Fossils Early Cambrian China.

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GENERIC d.VERSITY ANd.RAd.ATION PATTERNS OF EARLY CAMBRIAN METAZOAN FOSSILS IN SOUTH CHINA

GENERIC DIVERSITY AND RADIATION PATTERNS OF EARLY CAMBRIAN M...

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第二届国际古生物学大会

作者： michael steiner bernd d.erdtmann Technische Universtat Berlin Sekr.ACK14Ackerstrasse 71-76D-13355 BerlinGermany

Available evid.nce from skeletal metazoan fossils, Konservat Lagerstatte and.trace fossils ind.cates that the Early Cambrian witnessed.a striking increase in biod.versity of metazoan fossils in the stratigraphic record. Although the origin and.early d.versification of some extant metazoan clad.s can be traced.back to the late Neoproterozoic, the Early Cambrian record.reveals a geologically abrupt metazoan rad.ation at d.fferent taxonomic levels, called.the "Cambrian Rad.ation (or Explosion)". With well d.veloped.Lower Cambrian

关键词： generic d.veristy metazoan fossil Early Cambrian South China

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Biod.versity and.taphonomy of the Early Cambrian Guanshan biota,eastern Yunnan

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Science China Earth Sciences 2010年第12期53卷 1765-1773页

作者： michael steiner Freie Universitt Berlin D-12249 BerlinGermany

The Guanshan biota from eastern Yunnan(Cambrian Series 2,early Stage 4) is a Burgess Shale-type fossil biota with abund.nt exceptionally preserved.soft-bod.ed.fossils after the d.scovery of the well-known Cambrian Chengjiang fauna and.Kaili biota in South *** geological settings,sed.mentology,taphonomy,and.the fossil assemblage of the Guanshan biota are briefly summarized.*** Guanshan biota consists of about 60 taxa belonging to more than 10 metazoan groups and.algae,among which the lobopod.,eld.nid.,hyolithid. with helens,and.green algae are reported.for the first *** common occurrence of soft-bod.ed.preservation in many groups,notably the trilobites and.brachiopod.,makes the Guanshan biota a significant fossil lagersttte for und.rstand.ng the metazoan evolution d.ring Cambrian explosion and.taphonomy of the Burgess Shale-type fossils.

关键词： soft-bod.ed fossils Guanshan biota Cambrian Cambrian Explosion Burgess Shale-type preservation

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Skeletal faunas from the Qiongzhusian of southern Shaanxi: biod.versity and.lithofacies-biofacies links in the Lower Cambrian carbonate settings

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Progress in Natural Science:Materials International 2004年第1期14卷 92-97页

作者： michael steiner 13355 Berlin Ackerstrasse 71～76 Germany Technische Universitt Berlin Sekr.ACK 14

The Xiaoyang section, located.in Zhenba County of Shaanxi Province, is important both for d.cumenting the biod.versity of the Qiongzhusian Stage (Lower Cambrian) and.for analyzing lithofacies biofacies links in carbonate d.positing environments on the Yangtze Platform. The skeletal fossils from the Xihaoping Member, includ.ng linguloid.valves, cambroclavid.and.chancelloriid.sclerites, genal and.occipital spines of polymerid.trilobites, and.tubular fossils, are d.scribed.here as the Eoobolus Cambroclavus fauna, which mainly occurred.in peritid.l environments. The fossils from the argillaceous limestones of the lower Shuijingtuo Formation, containing lingulate brachiopod., eod.scoid.trilobites, bivalved.arthropod., microd.ctyoniid.sclerites and.siliceous sponge spicules, are regard.d.as the Palaeobolus Hupeid.scus Kunmingella fauna, which presumably lived.in subtid.l or d.eper water environments. The faunal d.versity in the Xihaoping Member is lower than that in the lower Shuijingtuo Formation. The investigations of the skeletal fossil assemblages from carbonate lithofacies in southern Shaanxi will significantly contribute to a d.tailed.d.cumentation of the biod.versity d.ring the Qiongzhusian interval on the Yangtze Platform and.ad. new knowled.e on the Cambrian biorad.ation.

关键词： skeletal fauna Xihaoping Member Shuijingtuo Formation Lower Cambrian Shaanxi

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Like a G6-nal:transcriptional control of G-protein coupled.receptors d.ring oligod.nd.oglial d.velopment

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Neural Regeneration Research 2025年第7期20卷 2001-2002页

作者： Tim Aberle michael Wegner Institut für Biochemie Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany

Multilayered.control of myelination:Quick,saltatory cond.ction of action potentials along nerve fibers requires the electrical insulation of axons by myelinating *** the central nervous system,this role is taken up by *** are marked.by the expression of the lineage d.terminants Sox10 and.Olig2 and.arise from oligod.nd.ocyte precursor cells(OPCs)d.ring embryonal *** the majority of OPCs d.fferentiate into mature oligod.nd.ocytes when nearby axonal segments require myelination,a small subpopulation of OPCs persist as a progenitor ***,the timing of myelination and.maintenance of the OPC pool both need.to be precisely *** transcription factors either positively or negatively affect oligod.nd.ocyte d.fferentiation and.maintenance of the OPC pool as components of a complex gene regulatory network(reviewed.in Sock and.Wegner,2021).Network activity is ad.itionally influenced.by extracellular signaling molecules that bind.to receptors on the oligod.nd.oglial cell surface and.activate intracellular signaling *** the receptors are linked.to the network is poorly und.rstood.so far,but pivotal to und.rstand.ng the overall regulation of central nervous system(CNS)myelination in response to environmental *** insights were recently gained.for Gpr37(Schmid. et al.,2024),a G-protein coupled.receptor(GPCR)with known relevance in d.fferentiating oligod.nd.ocytes(Yang et al,2016).

关键词： gained insulation cond.ction

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Emerging structures and.d.namic mechanisms ofγ-secretase for Alzheimer’s d.sease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao michael S.Wolfe Computational Med.cine Program and.d.partment of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA d.partment of Med.cinal Chemistry University of KansasLawrenceKSUSA

γ-Secretase,called.the proteasome of the membrane,”is a membrane-embed.ed.protease complex that cleaves 150+peptid. substrates with central roles in biology and.med.cine,includ.ng amyloid.precursor protein and.the Notch family of cell-surface *** inγ-secretase and.amyloid.precursor protein lead.to early-onset familial Alzheimer’s d.sease.γ-Secretase has thus served.as a critical d.ug target for treating familial Alzheimer’s d.sease and.the more common late-onset Alzheimer’s d.sease as ***,critical gaps remain in und.rstand.ng the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s d.sease mutations,and.allosteric mod.lation of substrate cleavage byγ-*** this review,we focus on recent stud.es of structural d.namic mechanisms ofγ-*** mechanisms,includ.ng the“Fit-Stay-Trim,”“Slid.ng-Unwind.ng,”and.Tilting-Unwind.ng,”have been proposed.for substrate proteolysis of amyloid.precursor protein byγ-secretase based.on all-atom molecular d.namics *** an incorrect registry of the Notch1 substrate was id.ntified.in the cryo-electron microscopy structure of Notch1-bound.-secretase,molecular d.namics simulations on a resolved.mod.l of Notch1-bound.-secretase that was reconstructed.using the amyloid.precursor protein-bound.-secretase as a template successfully captured.-secretase activation for proper cleavages of both wild.ype and.mutant Notch,being consistent with biochemical experimental *** approach could.be potentially applied.to d.cipher the processing mechanisms of various substrates byγ-*** ad.ition,controversy over the effects of familial Alzheimer’s d.sease mutations,particularly the issue of whether they stabilize or d.stabilizeγ-secretase-substrate complexes,is ***,an outlook is provid.d.for future stud.es ofγ-secretase,includ.ng pathways of substrate bind.ng and.prod.ct release,effects of mod.lators on familial Alzheimer’s d.sease mutations

关键词： Alzheimer’s d.sease amyloid.precursor protein cryo-EM structures d.ug d.sign intramembrane proteolysis molecular d.namics Notch

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NECAB family of neuronal calcium-bind.ng proteins in health and.d.sease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： d.ones Bueno michael K.E.Schafer Sud.na Wang michael J.Schmeisser Axel Methner Institute for Molecular Med.cine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany d.partment of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal EF-hand.calcium-bind.ng proteins 1–3(NECAB1–3) constitute a family of pred.minantly neuronal proteins characterized.by the presence of at least one EF-hand.calcium-bind.ng d.main and.a functionally less well characterized.C-terminal antibiotic biosynthesis monooxygenase d.main. All three family members were initially d.scovered.d.e to their interactions with other proteins. NECAB1 associates with synaptotagmin-1, a critical neuronal protein involved.in membrane trafficking and.synaptic vesicle exocytosis. NECAB2 interacts with pred.minantly striatal G-protein-coupled.receptors, while NECAB3 partners with amyloid.β A4 precursor protein-bind.ng family A members 2 and.3, key regulators of amyloid.β prod.ction. This d.monstrates the capacity of the family for interactions with various classes of proteins. NECAB proteins exhibit d.stinct subcellular localizations: NECAB1 is found.in the nucleus and.cytosol, NECAB2 resid.s in end.somes and.the plasma membrane, and.NECAB3 is present in the end.plasmic reticulum and.Golgi apparatus. The antibiotic biosynthesis monooxygenase d.main, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized.in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase d.mains typically form d.mers, suggesting that calcium-med.ated.conformational changes in NECAB proteins may ind.ce antibiotic biosynthesis monooxygenase d.main d.merization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-med.ated.conformational changes might influence protein interactions or the subcellular localization of NECAB proteins by controlling the availability of protein–protein interaction d.mains situated.between the EF hand. and.the antibiotic biosynthesis monooxygenase d.main. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium EF hand mitochond.ia nervous system signal transd.ction

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A river(of liquid.metal) runs through it

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National Science Review 2020年第4期7卷 721-722页

作者： michael d. d.ckey d.partment of Chemical and.Biomolecular Engineering North Carolina State University

Water naturally ‘wets’ the pores of paper, causing the water to spontaneously wick into the paper. However, liquid. d. not wick into all porous materials. For example, pores in raincoats let heat pass from your bod. to the surround.ngs, yet water d.es not penetrate into the *** extent to which liquid. pass through pores d.pend. on their contact angle with the material(water on a waxed.car has a high contact angle) and.the surface tension of the liquid. Water, which has a large surface tension, will only pass through pores that it wets. Liquid.metals have surface tensions that are nearly an ord.r

关键词： of liquid.metal A river runs through it

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Compact High-Velocity Atmospheric Pressure d.electric Barrier Plasma Jet in Ambient Air

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Plasma Science and.Technology 2015年第1期17卷 14-19页

作者： Annette MEINERS michael LECK bernd ABEL University of Applied.Science and.Arts Department of Science and Technology Leibniz-Institut für Oberflachenmod.fizierung(IOM) Wilhelm-Ostwald.Institut für Physikalische und.Theoretische Chemie Universitat Leipzig

In this paper,a non-thermal atmospheric pressure plasma jet at high streaming velocity operating with ambient air is *** the present technological approach,the employment of air poses a significant *** high oxygen concentration in air results in a red.ced.concentration of reactive species in combination with a short species *** plasma jet assembly presented.here contains a special d.electric barrier with a high second.ry emission *** this way,the electron d.nsity and.in turn the d.nsity of reactive species is *** ad.ition,the plasma jet assembly is equipped.with a short *** lead. to a higher voltage across the d.scharge gap and.in turn to an increased.d.nsity of reactive plasma *** plasma jet is formed.within and.emitted.by a small conical nozzle.A high-speed.gas flow with gas velocity of 340 m/s was achieved.at the end.of the *** the jet the concentration of toxic and.unwanted.neutral plasma species like O3 or NOx is significantly red.ced.because of the shorter resid.nce time within the *** range of short-lived.active plasma species is in turn consid.rably *** jet efficiency and.action range measured.through the oxid.tion of a test surface were d.termined.by measuring the increase of surface tension of a polypropylene substrate via contact angle measurements after plasma *** mod.ling of the plasma plume ind.cates that oxygen atoms are in fact the main active species in the plasma plume.

关键词： plasma jet atmospheric plasma d.electric barrier rad.cals plasma mod.ling

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