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Generation of brain vascular heterogeneity:recent advances from the perspective of angiogenesis

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Neural Regeneration Research 2025年第7期20卷 2013-2014页

作者： Nathanael j.Lee Ryota L.Matsuoka Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Molecular Medicine Cleveland Clinic Lerner College of MedicineCase Western Reserve UniversityClevelandOHUSA

Heterogeneous proper t i es of vascular endothelial cells in the brain:The brain displays large energy dynamics and consumption,and this high level of metabolic demands is fulfilled by a continuous supply of glucose and oxygen through its vascular *** vasculature consists of highly divergent blood vessel branches,giving rise to a dense network of capillaries that supply blood to all cells across the *** elaborated vascular network is thought to develop via angiogenesis,a process in which new blood vessels grow from pre-existing *** capillaries exhibit organotypic features distinct from other tissues and are formed primarily by two maj.r endothelial cell(EC)types:those that form the semi-permeable blood-brain barrier(BBB)and those that develop highly permeable pores known as fenestrae(Matsuoka et al.,2022).The structural and functional differences between BBB and fenestrated vascular ECs represent a fundamental feature of brain vasculature and form the foundation for both brain function and homeostasis.

关键词： angiogenesis homeostasis network

The role of organic electron donors in the initiation of BHAS base-induced coupling reactions between haloarenes and arenes

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Science China Chemistry 2019年第11期62卷 1425-1438页

作者： andrew j.Smith Darren L.Poole j.hn A.Murphy Department of Pure and Applied Chemistry University of StrathclydeStrathclydeGlasgow G11XLUnited Kingdom Flexible Discovery Unit GlaxoSmithKline Medicines Research CentreStevenageSG12NYUnited Kingdom

Coupling reactions between haloarenes and arenes(including heteroarenes)that are conducted without added transition metals but in the presence of KOtBu or NaOtBu,have been a topic of great interest since their discovery in *** organic structures act as additives that assist these *** additives are converted into organic electron donors by the butoxide base and this leads to initiation of the coupling reactions,which proceed by radical chain *** review provides an overview of the initiation stages of these reactions.

关键词： organic electron donor potassium tert-butoxide electron transfer base-promoted homolytic aromatic substitution(BHAS) coupling benzyne

Fabrication of Submicron-Diameter and Taper Fibers Using Chemical Etching

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j.urnal of Materials Science & Technology 2012年第4期28卷 308-312页

作者： Hani j. Kbashi Department of Physics College of Science University of Baghdad Baghdad Al-Jadriya-10070 Iraq

The thin, long length and high smoothness silica photonic nanowires and taper optical fiber were fabricated using a simple and low cost chemical etching method. A two-steps wet etch process were used consisting of etching with 30% HF acid to remove cladding and 24% HF acid to decrease fiber core diameter. An approach for on-line monitoring of etching using 1300 nm light power transmitted in the optical fiber was used to determine the diameter of the remaining core and showed a transition between two different operation regimes of nanofiber from the embedded regime, where the mode was isolated from the environment, to the evanescent regime. The data indicated that the diameter of the silica fiber decreased linearly for both 30% and 24% HF acid with 1.2 and 0.1/zm/min grad diameter, respectively at room temperature, and more than 70% of the mode intensity could propagate outside fiber when the core diameter was less than 1μm. The results of fiber taper showed that the fiber was tapered by a factor of 20 while retaining a thin core structure and leaving about more than 85% of core structure.

关键词： Chemical etching Submicron fiber Taper fibers

An Account of Chiral Metal Surfaces and Their Enantiospecific Chemistry

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Accounts of Materials Research 2021年第11期2卷 1024-1032页

作者： andrew j.Gellman Department of Chemical Engineering and W.E.Scott Institute for Energy Innovation Carnegie Mellon UniversityPittsburghPennsylvania 15213United States

CONSPECTUS:Molecular chirality has been of scientific interest since 1848 when Pasteur demonstrated its direct connection to the rotation of light by solutions of chiral *** the 1960s the connection was made between the chirality of pharmaceutical compounds and their physiological impact;one enantiomer can be therapeutic while the other is *** realization prompted enormous effort in the synthesis of enantiomerically pure compounds for bioactive use(a$300B/yr market).Until relatively recently,metals were ignored as potential substrates for asymmetric surface chemistry because metals have highly symmetric,achiral bulk structures and the premise was that they could not expose chiral *** 1996,we demonstrated that the high Miller index surfaces of metals can be chiral,existing in two enantiomeric forms M(hkl)R&S,and we hypothesized that they exhibit enantiospecific interactions with chiral *** such intrinsically chiral metal surfaces have ideal structural motifs based on low Miller index terraces separated by kinked monatomic *** Account begins with a short tutorial on the ideal and real structures of chiral metal surfaces to provide a firm basis for understanding the origin of their *** then chronicles the evolution of our understanding of their enantiospecific interactions with chiral adsorbates.

关键词： chiral metals realization

Distributed Transmit Beamforming for UAV to Base Communications

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China Communications 2019年第1期16卷 15-25页

作者： Yin Lu j.n Fang Zhong Guo j.andrew Zhang j.angsu Provincial Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Wuxi Longi Intelligent Technology Co.Ltd. University of Technology Sydney

Distributed transmit beamforming(DTB) is very efficient for extending the communication distance between a swarm of UAVs and the base,particularly when considering the constraints in weight and battery life for payloads on *** this paper,we review maj.r function modules and potential solutions in realizing DTB in UAV systems,such as timing and carrier synchronization,phase drift tracking and compensation,and beamforming vector generation and *** then focus on beamforming vector generation and updating,and introduce a concatenated training scheme,together with a recursive channel estimation and updating *** also propose three approaches for tracking the variation of channels and updating the *** effectiveness of these approaches is validated by simulation results.

关键词： unmanned aerial vehicle distributed transmit beamforming beamforming vector generation and updating channel prediction

HYERS—ULAM—RASSIAS STABILITY OF QUADRATIC FUNCTIONAL EQUATIONS IN BANACH MODULES OVER A C^＊—ALGEBRA

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Chinese Annals of Mathematics,Series B 2003年第2期24卷 261-266页

作者： C. PARK j. PARK j. SHIN Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.

The authors prove the Hyers-Ulam-Rassias stability of the quadratic mapping in Banachmodules over a unital C*-algebra, and prove the Hyers-Ulam-Rassias stability of the quadraticmapping in Banach modules over a unital... 详细信息

关键词： Stability B-quadratic Functional equation Banach module over Banach algebra

A Novel Training Algorithm of Genetic Neural Networks and Its Application to Classification

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j.urnal of Systems Engineering and Electronics 2001年第3期12卷 76-84页

作者： Xiao, j. Wu, j. Yang, S. School of Mechanics Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

First of all, this paper discusses the drawbacks of multilayer perceptron (MLP), which is trained by the traditional back propagation (BP) algorithm and used in a special classification problem. A new training algorithm for neural networks based on genetic algorithm and BP algorithm is developed. The difference between the new training algorithm and BP algorithm in the ability of nonlinear approaching is expressed through an example, and the application foreground is illustrated by an example.

关键词： Backpropagation Computer simulation Genetic algorithms Mathematical models Nonlinear control systems Problem solving

Assessing the impact of natural enemies in agroecosystems： toward ＂real＂ IPM or in quest of the Holy Grail？

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Insect Science 2015年第1期22卷 1-5页

作者： Myron P. Zalucki Michael j. Furlong Nancy A. Schellhorn Sarina Macfadyen andrew P. Davies School of Biological Sciences The University of Queensland Brisbane QLD 4072 Australia CSIRO Ecosystem Sciences and Sustain-able Agriculture Flagship Brisbane QLD 4001 Australia CSIRO Ecosystem Sciences and Sustainable Agriculture Flagship CanberraACT 2601 Australia CSIRO Australian Cotton Research Institute (ACRI) Narrabri NSW 2390 Australia Saunders Havill Group Bowen HillsBrisbane QLD 4006 Australia.

Go to virtually any conference or symposium on insect pests and so called ＂Integrated Pest Management,＂ or IPM, is presented as the answer to all management problems. IPM is the textbook paradigm （e.g., Kogan, 1998; Pedigo, 2002; Pedigo ＆ Rice, 2009） that guides all aspects of insect pest management research and implementation （Zalucki et al., 2009）. In most cases the way IPM is put in to practice, as opposed to the textbook j.rgon could, somewhat cynically, be regarded as ＂incidental＂ to pesticide management. How did it come to this？

关键词： IPM 农业生态系统有害生物综合治理天敌评估管理问题综合防治农药管理

Ribozymes and the mechanisms that underlie RNA catalysis

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Frontiers of Chemical Science and Engineering 2016年第2期10卷 178-185页

作者： Timothy j. Wilson Yij.n Liu David M. j. Lilley Cancer Research UK Nucleic Acid Structure Research Group MSI/WTB Complex The University of Dundee Dundee DD1 5EH UK

Ribozymes are widespread, and catalyze some extremely important reactions in the cell. Mechanistically most fall into one of two classes, using either metal ions or general acid-base catalysis. The nucleolytic ribozymes fall into the latter class, mostly using nucleobases. A sub-set of these use a combination of guanine base plus adenine acid to catalyze the cleavage reaction. New ribozymes are still being discovered at regular intervals and we can speculate on the potential existence of ribozymes that catalyze chemistry beyond phosphoryl transfer reactions, perhaps using small-molecule coenzymes.

关键词： RNA catalysis RNA structure catalytic mechanism