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Postcranial disparity of galeaspids and the evolution of swimming speeds in stem-gnathostomes

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National Science Review 2023年第7期10卷 81-90页

作者： Zhikun Gai Xianghong Lin Xianren Shan Humberto G.Ferrón philip c.J.Donoghue Key Laboratory of Vertebrate Evolution and Human Origins of chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences University of chinese Academy of Sciences Bristol Palaeobiology Group School of Earth Sciences University of Bristol Instituto cavanilles de Biodiversidad i Biología Evolutiva Universitat de València

Galeaspids are extinct jawless relatives of living jawed vertebrates whose contribution to understanding the evolutionary assembly of the gnathostome bodyplan has been limited by absence of postcranial ***,we describe Foxaspis novemura *** ***.,based on complete articulated remains from a newly discovered Konservat-Lagerstatte in the Early Devonian(Pragian,～410 Ma) of Guangxi,South china.F,novemura had a broad,circular dorso-ventrally compressed headshield,slender trunk and strongly asymmetrical hypochordal tail fin comprised of nine ray-like scale-covered *** tail morphology contrasts with the symmetrical hypochordal tail fin of Tujiaaspis vividus,evidencing disparity in galeaspid postcranial *** of swimming speed reveals galeaspids as moderately fast swimmers,capable of achieving greater cruising swimming speeds than their more derived jawless and jawed *** analyses reject the hypothesis of a driven trend towards increasingly active food acquisition which has been invoked to characterize early vertebrate evolution.

关键词： Galeaspida jawed vertebrates evolution functional morphology phylogenetics modelling

Tree Population Dynamics of Three Altitudinal Vegetation communities on Mount cameroon(1989-2004)

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Journal of Mountain Science 2011年第4期8卷 495-504页

作者： philip F.FORBOSEH Terry c.H.SUNDERLAND James A.cOMISKEY Michael BALINGA Plan cameroon P O Box 25236 MessaYaoundéCameroon centre for International Forestry Research(cIFOR) Inventory and Monitoring Program National Park Service120 Chatham Lane Smithsonian Institution S.Dillon Ripley Center1100 JeffersonDrive SW Washington DC 20560USA center for International Forestry Research(cIFOR)

changes in permanent sample plots in the lowland,submontane and montane forests on Mount cameroon(4,095 m above sea level),an active volcano,are described for 15 years from 1989 to *** the study period,the stocking level of trees with a diameter at breast height(DBH) ≥ 10 cm in the three forests were lower than in pan-tropical stands suggesting a significant impact of volcanic and human-related activities on the vegetation communities on the *** mortality rates in the submontane and montane forests were consistent with those reported for comparable altitudinal ranges in the Blue Mountains of *** annual mortality rate was higher in the lowland forest than other lowland sites *** between recruitment and mortality rates was large suggesting that the three vegetation communities have not reached their *** seven-year difference in half-life of large trees(with a DBH ≥ 50 cm) in the submontane and montane forests suggests an altitudinal effect on turnover of larger trees that in turn contributes to the frequent small stature of high altitude *** was little evidence of an altitudinal effect on species turnover and growth *** finding supports generalizations about the zero effect of growth on the stature of high altitude *** forest dynamics is crucially important in the management of tropical montane environmentsand in this instance particularly so given the recent creation of the Mount cameroon National Park.

关键词： Growth rates Recruitment Mortality Altitude Half-life Mount cameroon

Target tracking method of Siamese networks based on the broad learning system

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cAAI Transactions on Intelligence Technology 2023年第3期8卷 1043-1057页

作者： Dan Zhang c.L.philip chen Tieshan Li Yi Zuo Nguyen Quang Duy Navigation college Dalian Maritime UniversityDalianChina Innovation and Entrepreneurship Education college Dalian Minzu UniversityDalianChina computer Science and Engineering college South China University of TechnologyGuangzhouChina Department of computer and Information Science Faculty of Science and TechnologyUniversity of MacaoMacaoChina School of Automation Engineering University of Electronic Science and Technology of ChinaChengduChina Faculty of Navigation Vietnam Maritime UniversityHaiphongVietnam

Target tracking has a wide range of applications in intelligent transportation,real‐time monitoring,human‐computer interaction and other ***,in the tracking process,the target is prone to deformation,occlusion,loss,scale variation,background clutter,illumination variation,etc.,which bring great challenges to realize accurate and real‐time *** based on Siamese networks promotes the application of deep learning in the field of target tracking,ensuring both accuracy and real‐time ***,due to its offline training,it is difficult to deal with the fast motion,serious occlusion,loss and deformation of the target during ***,it is very helpful to improve the performance of the Siamese networks by learning new features of the target quickly and updating the target position in time *** broad learning system(BLS)has a simple network structure,high learning efficiency,and strong feature learning *** at the problems of Siamese networks and the characteristics of BLS,a target tracking method based on BLS is *** method combines offline training with fast online learning of new features,which not only adopts the powerful feature representation ability of deep learning,but also skillfully uses the BLS for re‐learning and re‐*** broad re‐learning information is used for re‐detection when the target tracking appears serious occlusion and so on,so as to change the selection of the Siamese networks search area,solve the problem that the search range cannot meet the fast motion of the target,and improve the *** results show that the proposed method achieves good results on three challenging datasets and improves the performance of the basic algorithm in difficult scenarios.

关键词： broad learning system siamese network target tracking

“One-day,one-stay,and one-step”lessons from the Danish guidelines for the treatment of gallstone disease

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Hepatobiliary Surgery and Nutrition 2023年第4期12卷 607-610页

作者： Robert c.Verdonk philip R.de Reuver Department of Gastroenterology&Hepatology St.Antonius HospitalNieuwegeinThe Netherlands Department of Surgery Radboud University Medical CenterNijmegenThe Netherlands

*** disease is prevalent worldwide,and the incidence in Europe increased over the last *** median prevalence ranges from 5.9%to 21.9%,with the highest rates seen in Norway(21.9%)and the eastern part of Germany(19.7%)and the lowest rates in Italy(c gallstones annually,costing around 250 million euros,ranking gallstones disease in the top 10 of the most prevalent and costly gastrointestinal disorders(2).

关键词： Uncomplicated gallstone disease cholecystitis common bile duct stones

Five trends of education and technology in a sustainable future

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Geography and Sustainability 2020年第2期1卷 93-97页

作者： Nicholas c.Burbules Guorui Fan philip Repp Department of Educational Policy Organization and LeadershipUniversity of IllinoisUrbana-ChampaignUrbanaIL 61801United States Institute of Education Governance Faculty of EducationEast China Normal UniversityShanghai 200062China Office of Information Technology Western Michigan UniversityKalamazoo MI 49008-5200United States

Quality education is one of the pillars in the United Nations 2030 Agenda for Sustainable Development,which aims to ensure inclusive and equitable quality education and promote lifelong learning opportunities for *** overall goal can be connected to some general trends affecting education in the information *** argue that education is key to the future quality of human life and the sustainability of the ***,education is being transformed in both formal and informal learning contexts by new digital ***,some of these major innovations and how they are changing education can be summarized into the following aspects:1)our educational aims and objectives;2)educational ecologies and contexts of learning;3)the processes of learning;4)the processes of teaching;and 5)educational governance and ***,we note some of the potential risks and downsides of these technology *** the sustainable perspective,our review points to a great potential for educational reform,but it can only be achieved if we are willing to rethink and even abandon some of our traditional ways of doing things in education.

关键词： Education for sustainable development Educational technology Educational transformation Learning and teaching Governmental policy

A proposed U.S./china theoretical/experimental collaborative effort on baryon resonance extraction

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chinese Physics c 2009年第12期33卷 1222-1229页

作者： philip L. cole Idaho State University Department of Physics Pocatello Idaho 83209-8106 USA

In this paper we discuss the reasons for our work towards establishing a new collaboration between Jefferson Lab （JLab） and the Institute of High Energy Physics （IHEP） in Beijing. We seek to combine experimentalists and theorists into a dedicated group focused on better understanding the current and future data from JLab and from the Beijing Electron Positron collider （BEPc）. Recent JLab results on the extraction of single- and double-polarization observables in both the lπ- and 2π-channel show their high sensitivity to small production amplitudes and therefore their importance for the extraction of resonance parameters. The Beijing Electron Spectrometer （BES） at the BEPc has collected high statistics data on J/ψ production. Its decay into baryon-antibaryon channels offers a unique and complementary way of probing nucleon resonances. The cEBAF Large Acceptance Spectrometer, cLAS, has access to N＊ form factors at high Q2 which is advantageous for the study of dynamical properties of nucleon resonances, while the low-background BES results will be able to provide guidance for the search for less-dominant excited states at JLab. Moreover, with the recently approved experimental proposal Nucleon Resonance Studies with cLAS12 and the high-quality data streaming from BES-Ⅲand cLAS, the time has come for forging a new Trans-Pacific collaboration of theorists and experimentalists on NSTAR physics.

关键词： baryon resonances electromagnetic form factors J/ψ production cEBAF Large AcceptanceSpectrometer (cLAS) Jefferson Laboratory (JLab) Beijing Electron Spectrometer (BES) Beijing ElectronPositron collider (BEPc) Institute of High Energy Physics (IHEP)

Adaptive control of MIMO Mechanical Systems with Unknown Actuator Nonlinearities Based on the Nussbaum Gain Approach

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IEEE/cAA Journal of Automatica Sinica 2016年第1期3卷 26-34页

作者： ci chen Zhi Liu Yun Zhang c.L.philip chen Shengli Xie School of Automation Guangdong University of Technology IEEE Faculty of Science and Technology University of Macao Guangdong Key Laboratory of IoT Information Processing

This paper investigates MIMO mechanical systems with unknown actuator nonlinearities. A novel Nussbaum analysis tool for MIMO systems is established such that unknown time-varying control coefficients are tackled. In contrast to existing literatures on continuous-time systems, the newly-developed Nussbaum tool focuses on extending the traditional Nussbaum result from one dimensional case to the multiple one. Specifically, not only the multiple unknown input coefficients are extended to the time-varying, but also the limitation of the prior knowledge of coefficients' upper and lower bounds is removed. Furthermore, an adaptive robust controller associated with the proposed tool is presented. The asymptotic tracking of MIMO mechanical systems is guaranteed with the help of the Lyapunov Theorem. Finally, a simulation example is provided to examine the validity of the proposed scheme. © 2014 chinese Association of Automation.

关键词： Actuators Adaptive control systems control nonlinearities Mechanical actuators Mechanics MIMO systems Time varying control systems

Sailing Through the Storm: A Strategic Review of cNOOc’s Unocal Acquisition

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Petroleum Science 2006年第4期3卷 10-14页

作者： chang philip c. Wang Zhen University of calgary Canada china University of Petroleum Beijing 102249 China

cNOOc＇s 2005 attempt to take over Unocal was dubbed by some chinese media as ＂Acquisition of the century＂, as the $18.5 billion bid was the largest-ever overseas acquisition by a chinese company. cNOOc eventually withdrew its offer after chevron joined the bidding war and political sentiment in the U.S. congress became hostile. This paper analyzes the competitive bidding process and provides a strategic review. cNOOc＇s advantages in the acquisition included its international expertise, financing capability, access to the growing chinese market, and its willingness to retain Unocal staff after the merger. The main challenges were corporate governance, especially the understanding of the role of the board and the management of political risk in the U.S. In hindsight a pledge to divest Unocal＇s U.S. assets and not to give any impression of using subsidized loans could have helped deflect some political criticisms. Eventually, the U.S. government published the required energy security study in 2006 and it provided no support to the political concerns of the congress.

关键词： Strategy political risk cNOOc Unocal chevron

MicroRNAs in laser-induced choroidal neovascularization in mice and rats:their expression and potential therapeutic targets

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Neural Regeneration Research 2021年第4期16卷 621-627页

作者： Bridget Martinez philip V.Peplow Physical chemistry and Applied Spectroscopy Chemistry DivisionLos Alamos National LaboratoryLos AlamosNMUSA Department of Medicine St.Georges University School of MedicineGrenada Department of Anatomy University of OtagoDunedinNew Zealand

choroidal neovascularization characterizes wet age-related macular *** neovascularization formation involves a primarily angiogenic process that is combined with both inflammation and proteolysis.A primary cause of choroidal neovascularization pathogenesis is alterations in pro-and anti-angiogenic factors derived from the retinal pigment epithelium,with vascular endothelium growth factor being mainly responsible for both clinical and experimental choroidal ***(miRNAs)which are short,non-coding,endogenous RNA molecules have a major role in regulating various pathological processes,including inflammation and angiogenesis.A review of recent studies with the mouse laser-induced choroidal neovascularization model has shown alterations in miRNA expression in choroidal neovascularization tissues and could be potential therapeutic targets for wet age-related macular *** of miR-505(days 1 and 3 post-laser),miR-155(day 14)occurred in retina;miR-342-5p(days 3 and 7),miR-126-3p(day 14)in choroid;miR-23a,miR-24,miR-27a(day 7)in retina/choroid;miR-505(days 1 and 3)in retinal pigment epithelium/choroid;downregulation of miR-155(days 1 and 3),miR-29a,miR-29b,miR-29c(day 5),miR-93(day 14),miR-126(day 14)occurred in retinal pigment epithelium/*** using miRNA mimics or inhibitors were found to decrease choroidal neovascularization *** neovascularization development was reduced by overexpression of miR-155,miR-188-5p,miR-(5,B,7),miR-126-3p,miR-342-5p,miR-93,miR-126,miR-195a-3p,miR-24,miR-21,miR-31,miR-150,and miR-184,or suppression of miR-505,miR-126-3p,miR-155,and miR-23/*** studies are warranted to determine miRNA expression in mouse laser-induced choroidal neovascularization models in order to validate and extend the reported *** experimental variables need to be standardized;these include the strain and age of animals,gender,number and position of laser burns to the e

关键词： age-related macular degeneration angiogenesis animal model blood plasma choroid laser microRNAs neovascularization retina retinal pigment epithelium therapeutic targets vascular endothelial growth factor