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Phylogenetic positions of two marine ciliates, Metanophrys similis and Pseudocohnilembus hargisi (Protozoa, Ciliophora,Scuticociliatia), inferred from complete small subunit rRNA gene sequences

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Progress in Natural Science:Materials International 2006年第4期16卷 373-378页

作者： alan WARREN Department of Zoology The Natural History Museum Cromwell Road London SW7 5BD UK

The small subunit rRNA (SSrRNA) gene was sequenced for two marine scuticociliates Metanophrys similis and Pseudocohnilembus hargisi. The results show that this gene comprises 1763 and 1753 nucleotides in the two marine ciliates respectively. Metanophrys similis is phylogenetically closely related to the clade containing Mesanophrys carcini and Anophyroides haemophila, which branches basally to other species within the order Philasterida. Pseudocohnilembus hargisi groups with its congener, P. marinus, with strong bootstrap support. Paranophrys magna groups with the clade including Cohnilembus and Uronema, representing a sister clade to that containing the two Pseudocohnilembus species.

关键词： phytogeny protozoa scuticociliate Metanophrys similis Pseudocohnilembus hargisi.

Estimation of projected surface area of irregularly shaped fragments

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Defence Technology（防务技术） 2019年第2期15卷 198-209页

作者： Elvedin Kljuno alan Catovic Mechanical Engineering Faculty University of Sarajevo

The essence and the main contribution of this paper are consisted of the suggested novel method for estimation of a projected surface area of an irregularly shaped fragment, which represents a significant step toward a new method of an aerodynamic force estimation of a fragment motion through a resistive medium. The suggested method is to use a tri-axial ellipsoid that has a continuous surface(given as a mathematical function) to approximate an irregularly shaped fragment so that the fragment trajectory can be estimated faster taking into consideration that the aerodynamic force is proportional to a projected surface area of the *** their motion, fragments can take any orientation relative to the velocity vector and aerodynamic force is proportional to a projected surface area of fragment perpendicular to the velocity vector,so it is necessary to have a method for correct estimation of the projected area in an arbitrary direction relatively to the *** model was validated with analytical and CAD techniques, and verified using 3D model of a real fragment. The comparison of the projected surface area values for the fragment, obtained using the CAD tools and using our model, are generally in good agreement, This method represents a step toward modeling that does not require a CFD result for estimation of the aerodynamic force of irregularly shaped bodies.

关键词： Projected area Fragments Trajectory

A generalized model for estimation of aerodynamic forces and moments for irregularly shaped bodies

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Defence Technology（防务技术） 2019年第3期15卷 369-389页

作者： Elvedin Kljuno alan Catovic Mechanical Engineering Faculty University of Sarajevo

A novel method for estimation of an aerodynamic force and moment acting on an irregularly shaped body (such as HE projectile fragments) during its flight through the atmosphere is presented. The model assumes that fragments can be approximated with a tri-axial ellipsoid that has continuous surface given as a mathematical function. The model was validated with CFD data for a tri-axial ellipsoid and verified using CFD data on aerodynamic forces and moments acting on an irregularly shaped fragment. The contribution of this method is that it represents a significant step toward a modeling that does not require a cumbersome CFD simulation results for estimation of fragment dynamic and kinematic parameters. Due to this advantage, the model can predict the fragment motion consuming a negligible time when compared to the corresponding time consumed by CFD simulations. Parametric representation (generalization) of the fragment geometrical data and the conditions provides the way to analyze various correlations and how parameters influence the dynamics of the fragment flight.

关键词： Aerodynamic force Aerodynamic moment Fragments

生态文明视野下杭州市水文化遗产资源的保护与利用

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浙江水利水电学院学报 2024年第4期36卷 8-11页

作者：房利苏阿兰浙江机电职业技术学院浙江杭州310053

杭州市水文化遗产具有历史文化底蕴深厚、文化类型丰富、水乡地域特色鲜明的特点,凝聚成杭州山水之城的灵魂。杭州市水文化遗产在保护和利用方面存在新发展理念贯彻不到位、资源整合困难、遗产活化不足、开发利用同质化严重等问题。因此... 详细信息

杭州市水文化遗产具有历史文化底蕴深厚、文化类型丰富、水乡地域特色鲜明的特点,凝聚成杭州山水之城的灵魂。杭州市水文化遗产在保护和利用方面存在新发展理念贯彻不到位、资源整合困难、遗产活化不足、开发利用同质化严重等问题。因此,在建设生态文明和美丽城市的背景下,杭州市水文化遗产要在坚持生态文明观的前提下,从贯彻生态文明理念,强化遗产活化传承,推进文旅融合发展等方面进行保护与利用,不仅要充分发挥水文化遗产的历史文化价值,还要实现生态、文化、经济效益三者的统一。

关键词：生态文明水文化遗产保护与利用

Generalized Hopfian Property, a Minimal Haken Manifold, and Epimorphisms Between 3-Manifold Groups

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Acta Mathematica Sinica,English Series 2002年第1期18卷 157-172页

作者： REID alan W Department of Mathematics. University of Texas Austin. TX 78712. USA

We address the question that if π_1-surjective maps between closed aspherical 3-manifolds have the same rank on π_1 they must be of non-zero degree. The positive answer is proved for Seifert manifolds, which is used in constructing the first known example of minimal Haken manifold. Another motivation is to study epimorphisms of 3-manifold groups via maps of non-zero degree between 3- manifolds. Many examples are given.

关键词： Non-zero degree maps Epimorphisms 3-Manifolds

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经济学家如何影响世界大战

中国改革 2024年第2期 80-81页

作者：艾伦·博拉尔德新西兰惠灵顿维多利亚大学

这是一本关于经济学的书,但也是一个关于人性的故事将军不能仅凭自己赢得战争。本书讲述了六个国家的七位经济学家在1935—1955年世界频繁爆发各类战争期间扮演的角色,其中涵盖了中国的抗日战争、第二次世界大战和冷战。这些经济学家来... 详细信息

这是一本关于经济学的书,但也是一个关于人性的故事将军不能仅凭自己赢得战争。本书讲述了六个国家的七位经济学家在1935—1955年世界频繁爆发各类战争期间扮演的角色,其中涵盖了中国的抗日战争、第二次世界大战和冷战。这些经济学家来自不同的背景,有着不同的立场,面对不同的挑战。这是一个关于好与坏的经济思维、好与坏的政策、好与坏的道德立场的故事。尽管存在差异,但这七位经济学家也有相似之处或者互有联系。

关键词：道德立场世界大战经济学家抗日战争扮演的角色故事

Differentiation and functional connectivity of fetal tectal transplants

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Neural Regeneration Research 2023年第11期18卷 2325-2331页

作者： alan R.Harvey School of Human Sciences The University of Western AustraliaLions Eye Instituteand Perron Institute for Neurological and Translational ScienceNedlandsWAAustralia

Data from studies analyzing the differentiation and functional connectivity of embryo nic neural tissue grafted into the mammalian nervous system has led to the clinical testing of the fetal graft approach in patients with neurodegenerative *** some success has been achieved,ethical concerns have led to a search for alternative therapeutic strategies,mostly exploring the use of neural precursors or neurons derived from pluripotent stem cells to replace damaged host neurons and restore lost *** more recent studies address questions of graft viability,differentiation,and connectivity similar to those posed by researchers in earlier fetal transplant work,thus reviews of the fetal graft literature may inform and help guide ongoing research in the stem cell/organoid *** brief review describes some key observations from research into the transplantation of neural tissue into the rat visual syste m,focusing on grafts of the fetal supe rior colliculus(tectal grafts) into neonatal or adult *** neonate hosts,grafts quickly develop connections with the underlying host mid b rain and attain a morphology typical of mature grafts by about 2 weeks.G rafts consistently contain numerous localized regions which,based on neurofibrillar staining,neuronal morphology(Golgi),neurochemistry,receptor expression,and glial architecture,are homologous to the stratum griseum supe rficiale of normal superior *** localized "patches" are also seen after explant culture and when donor tectal tissue is dissociated and reaggregated prior to *** almost all circumstances,host retinal innervation is restricted to these localized patches,but only those that are located adjacent to the graft surfa *** are formed and there is evidence of functional *** only exception occurs when Schwann cells are added to dissociated tecta prior to *** these co-grafts,the peripheral glia appear to compete with local target fa ctors a

关键词： axon regeneration differentiation embyronic grafts fetal tissue neural precursors retinotectal stem cells superior colliculus synaptogenesis transplantation

Review of mass-flow hopper design with respect to stress fields and surcharge loads

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Particuology 2010年第6期8卷 591-594页

作者： alan W.Roberts Centre for Bulk Solids and Partculate Technologies The University of NewcastleNSWAustralia

Current procedures for mass-flow hopper design are based on the radial stress theory developed byJenike and involve the determination of the critical outlet dimensions for flow to be initiated. These procedures ignore the surcharge loads on the hopper and involve a study of the passive or arched stress field that exists under flow conditions. An alternative approach as applied to hopper wall load analysis is to employ the horizontal slice method. The arched stress field and horizontal slice methods of analysis are compared. The influence of surcharge loads in the determination of hopper geometry is investigated.

关键词： Mass-flow Surcharge pressure Cohesive arching

A Neuro-Muscular Elasto-Dynamic Model of the Human Arm Part 1:Model Development

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Journal of Bionic Engineering 2009年第2期6卷 93-107页

作者： alan A.Barhorst Lawrence Schovanec Texas Tech University Department of Mechanical Engineering Texas Tech University Department of Mathematics and Statistics

In this paper we develop an elasto-dynamic model of the human arm for use in neuro-muscular control and dynamic interaction *** motivation for this work is to present a case for developing and using non-quasistatic models of human musculo-skeletal *** model is based on hybrid parameter multiple body system(HPMBS)variational projection *** this paper,we present an overview of the HPMBS variational principle applied to the full elasto-dynamic model of the *** generality of the model allows one to incorporate muscle effects as either loads transmitted through the tendon at points of origin and insertion or as an effective torque at a *** the technique is suitable for detailed bone and joint modeling,we present in this initial effort only simple geometry with the bones discretized as Rayleigh beams with elongation, while allowing for large *** demonstrate the viability of the mcthod for use in the companion paper and in future studies.

关键词： elasto-dynamics hybrid parameter system musculo-skeletal model neuro-muscular model