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Pterosaur Research:Recent Advances and a Future Revolution

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Acta Geologica Sinica(english edition) 2012年第6期86卷 1366-1376页

作者： david w.e.hone Department of earth Sciences University of Bristol School of Biological and Chemical Sciences Queen Mary University of London

In the years since the first description of a pterosaur specimen in 1784, pterosaur research has inevitably advanced considerably. However the last decade has arguably seen a much greater increase in our knowledge than the preceding two centuries. Since the turn of the new millennium, more than 40 new pterosaur genera and species have been described and whole new clades have been discovered, in addition to much new data being developed on pterosaur anatomy, functional morphology, palaeobiology, systematics, ecology and more. we are perhaps at the start of a golden age of pterosaur research and much as the dinosaurs underwent a revolution in the 1970s through to the early 1990s, now the Pterosauria are taking their turn. There is also a new and wider interest in pterosaur work as it attracts both more researchers and greater public interest. Pterosaurs appear to be an increasingly popular aspect of paleontology in popular culture and of interest to the media, both mainstream and digital.

关键词： paleontology Pterosauria science history of research academia

A New Chinese Anurognathid Pterosaur and the evolution of Pterosaurian Tail Lengths

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Acta Geologica Sinica(english edition) 2012年第6期86卷 1317-1325页

作者： LÜ Junchang david w.e.hone Institute of Geology Chinese Academy of Geological Sciences School of Biology and environmental Sciences University College Dublin

A new anurognathid pterosaur specimen from the Middle Jurassic Tiaojishan Formation of Qinglong, northern Hebie Province is described. The new specimen is referred to Dendrorhynchoides, based on the general morphology of the skeleton, but it represents a new species, named here as Dendrorhynchoides mutoudengensis sp. nov.. It is characterized by the presence of short, robust and straight teeth, and bearing wing metacarpal approximately 40% of the length of humerus. The new specimen provides further osteological information for anurognathid pterosaurs, especially the presence of a relatively elongate tail.

关键词： Pterosauria rhamphothynchoids anurognathid Dendrorhynchoides mutoudengensis,pterodactyloids tail evolution.

具长尾的树翼龙(翼龙目:蛙嘴龙科)新标本及翼龙类尾部的演化(英文)

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地球学报 2010年第S1期31卷 29-30页

作者： david w.e.hone Institute of Vertebrate Palaeontology and Palaeoanthropology

The anurognathids are a rare group of ‘rhampho-rhynchoid’ pterosaurs although increasing numbers of specimens are being described (e.g. Bennett,

关键词：蛙嘴龙科翼龙目翼龙类长尾标本演化尾部

长掌义县龙(兽脚类:恐龙)及其在手盗龙类进化和热河动物群生态学研究中的意义(英文)

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古脊椎动物学报 2012年第2期50卷 111-139页

作者： T．A1exander DeCeCCHI Hans C．e．LARSSON david w.e.hone 加拿大麦吉尔大学雷德帕思博物馆蒙特利尔H3A2K6 爱尔兰都柏林大学生物与环境科学学院都柏林4

重新研究了产于辽西义县组下部的带羽毛小型兽脚类恐龙长掌义县龙(Yixianosaurus longimanus) 的不完整骨架。系统发育分析得出义县龙属于手盗龙类基干类群,与阿尔瓦雷斯龙( Alvarezsaurus) 、镰刀龙类、除阿尔瓦雷斯龙之外的其他阿尔... 详细信息

重新研究了产于辽西义县组下部的带羽毛小型兽脚类恐龙长掌义县龙(Yixianosaurus longimanus) 的不完整骨架。系统发育分析得出义县龙属于手盗龙类基干类群,与阿尔瓦雷斯龙( Alvarezsaurus) 、镰刀龙类、除阿尔瓦雷斯龙之外的其他阿尔瓦雷斯龙类以及由窃蛋龙类和副鸟龙类等进步手盗龙类组成的一个类群形成多分支状态。义县龙既有原始特征,如臂指数低,第三指强壮; 也有进步特征,如乌喙骨近长方形,表明在手盗龙类当中,前肢演化呈现出比以前认为的更加复杂的镶嵌现象。强壮的前肢骨骼以及厚重、弯曲而尖利的手爪表明义县龙是捕食者,尽管这一认识尚待该属种更完整化石的发现来证实。义县龙在手盗龙类系统发育中的基部位置暗示,在虚骨龙类演化的这一节点上,前肢形态的变异范围更大。在许多方面,义县龙强壮的前肢和过度增大的弯曲爪子与长臂猎龙(Tanycolagreus) 和虚骨龙(Coelurus) 的相似,可能代表了这些属种与基干镰刀龙类和窃蛋龙类之间的过渡形态。义县龙保存了大的片状体羽,表明这些皮肤衍生物在虚骨龙类中的起源可能比以前报道的要早。最后,强壮而伸长的前肢暗示了其生态功能与根据同一区域的其他小型兽脚类推测的不同,支持了热河生物群的小型非鸟兽脚类中存在小生境划分的观点。

关键词：热河生物群恐龙手盗龙类指骨指数古生态学异速生长

Cultivating potential:Harnessing plant stem cells for agricultural crop improvement

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Molecular Plant 2024年第1期17卷 50-74页

作者： Penelope Lindsay Kyle w.Swentowsky david Jackson Cold Spring Harbor Laboratory Cold Spring HarborNY 11724USA National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhanHubei430070China

Meristems are stem cell-containing structures that produce all plant organs and are therefore important targets for crop *** regulators control the balance and rate of cell divisions within the *** these regulators impacts meristem architecture and,as a consequence,plant *** this review,we discuss genes involved in regulating the shoot apical meristem,inflorescence meristem,axillary meristem,root apical meristem,and vascular cambium in *** highlight several examples showing how crop breeders have manipulated developmental regulators to modify meristem growth and alter crop traits such as inflorescence size and branching *** transformation techniques are another innovation related to plant meristem research because they make crop genome engineering *** discuss recent advances on plant transformation made possible by studying genes controlling meristem ***,we conclude with discussions about how meristem research can contribute to crop improvement in the coming decades.

关键词： meristem crop improvement plant transformation plant breeding crop yield gene editing

Origins of perturbations in dayside equatorial ground magnetograms

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earth and Planetary Physics 2024年第1期8卷 215-221页

作者： Syau-Yun w.Hsieh david G.Sibeck The Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA NASA Goddard Space Flight Center GreenbeltMarylandUSA

To determine the cause(s)of perturbations seen in dayside equatorial ground magnetograms,we conducted a systematic survey of simultaneous ground-based and geosynchronous satellite-based observations during the 90-day period from December 1,2020 to February 28,*** examined Huancayo ground magnetometer observations from 14:00:00 to 20:00:00 UT each day,during which Huancayo passed through local *** those data we chose perturbation events selected on the basis of large(>20 nT)event amplitude and classified the selected events as responding primarily to solar wind pressure,or to variations in the north/south component of the interplanetary magnetic field(IMF Bz),or perhaps in part to *** results show that an equivalent number of events were identified for each model during this 90-day *** in the lagged solar wind dynamic pressure routinely correspond to nearly simultaneous sudden impulses recorded at both geosynchronous orbit and on the *** in IMF Bz produce erosion signatures at geosynchronous orbit and can correspond to ground events if lag times for reconnection to enhance convection in the magnetosphere are taken into account.

关键词： dayside magnetosphere dayside equatorial ionosphere geosynchronous magnetic field

A Dynamic Network Game of the Fintech Industry

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Journal of the Operations Research Society of China 2024年第1期12卷 5-33页

作者： david w.K.Yeung Leon A.Petrosyan Ying-Xuan Zhang SRS Consortium for Advanced Study in Cooperative Dynamic Games Shue Yan UniversityHong KongChina Center of Game Theory St Petersburg State UniversitySaint PetersburgRussia Department of Finance Asia UniversityTaichung CityTaiwanChina Faculty of Applied Mathematics-Control Processes and Center of Game Theory St Petersburg StateUniversitySaint PetersburgRussia

economies of scale,economies of scope,and technology spillover are decisive eco-nomic elements that are crucial to the development in the Fintech *** externalities are often realized through network *** this paper,we presenta dynamic network ofﬁnancialﬁrms which exhibits these decisive *** game equilibria are characterized.A Pareto efﬁcient solution involving col-laboration of allﬁrms is *** obtain a fair-share distribution of cooperativegains,the Shapley value is adopted as the sharing *** distributionmechanisms which guarantee the fulﬁlment of the Shapley value distribution in eachstage of the cooperation duration are derived.

关键词： Network game Network equilibria Shapley value Pareto efﬁcientcooperation

Mitochondrial recruitment in myelin:an anchor for myelin dynamics and plasticity?

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Neural Regeneration Research 2024年第7期19卷 1401-1402页

作者： Jean-david M.Gothié Timothy e.Kennedy Department of Neurology and Neurosurgery Montreal Neurological InstituteMcGill UniversityMontrealQCCanada

Optimal propagation of neuronal electrical impulses depends on the insulation of axons by myelin,produced in the central nervous system by *** is an extension of the oligodendrocyte plasma membrane,which wraps around an axon to form a compact multi-layered *** is composed of a substantially higher proportion of lipids compared to other biological membranes and enriched in a small number of specialized proteins.

关键词： plasticity insulation dynamics

Coating powder beds with liquids and foams based on viscous formulations using a twin screw mixer:A continuous process study

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Particuology 2024年第10期93卷 364-376页

作者： Mohamed S.Manga Dimitrios Kontziampasis Mustafa Al-Maqdad Sean Clifford Serafim Bakalis david w.York School of Chemical and Process engineering Faculty of Engineering and Physical SciencesUniversity of LeedsLeedsLS29JTUK School of Mechanical engineering Faculty of Engineering and Physical SciencesUniversity of LeedsLeedsLS29JTUK School of Science and engineering University of DundeeDD14HNDundeeScotlandUK Dundee International Institute of Central South University Tongzipo RoadCentral South UniversityChangshaHunan410013China Department of Chemical engineering School of EngineeringUniversity of NewcastleNewcastleNE17RUUK School of Chemical engineering University of BirminghamBirminghamB152TTUK Department of Chemical engineering Faculty of EngineeringUniversity of NottinghamNG72RDUK

Coating with viscous formulations has been essential in numerous industries as it can be a means for providing functionalization, additional properties, as well as other benefits. However, there have been scarce studies that have investigated and proposed methodologies in literature. Continuous coating of powders with viscous liquids poses as a promising technology, which has been mentioned in some studies, but has not yet been thoroughly investigated. This paper employs the use of image processing and analysis, in combination with statistical analysis of particles to evaluate the effectiveness of foams and liquids as a means of coating powder beds. Two different sizes of twin screw mixers that are working in continuous operation are employed, and a new continuous foaming device is fabricated and used for the experiments of coating. The effect of materials and process parameters (as for example rotational speed, and flowrate) on the quality of coating are investigated. Image analysis is used to assess the coating quality. The results clearly showcase the potential of using twin screw mixers for coating purposes and not only for mixing. The hypothesis that using large bubble foams to improve the coating of viscous liquids on particles is proven correct, as they provide higher quality coatings compared to their equivalent liquids, when used in the twin screw mixer. Surprisingly, using a larger scale twin screw mixer, does not show a substantial effect on the mixing, regarding quality, however there is still a requirement for mix optimization for achieving scale-up of this process. These results provide a new pathway for coating powders with viscous formulations in industrial applications, requiring less energy and effort in this process, and can pave the way towards introducing more sustainable industrial methodologies for coating.

关键词： Powder coating Continuous processing Viscous liquid Foam Image analysis Positron emission particle traking(PePT)