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美国艾奥瓦州文尼希克Lagerstatte及其沉积环境

2008 IEEE International Conference on Communications(ICC 2008)

This paper investigates an important tradeoff in wireless ad hoc networks concerning the allocation of resources to the PHY and MAC *** compare two approaches:One which employs a non-coordinated slotted ALOHA MAC with multi-antenna PHY,and one which employs a tightly coordinated MAC and single-antenna *** both cases,we derive new closed-form throughput *** on these,we show that using simple slotted ALOHA in conjunction with multiple antennas can provide a higher throughput than fully coordinated access protocols in various practical *** results are confirmed through comparison with Monte Carlo simulations.

关键词： Ad hoc networks Physical layer Throughput Media Access Protocol Peer to peer computing Interference Slot antennas Time division multiple access Array signal processing Paper technology

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高校地质学报 2009年第3期15卷 285-295页

作者：刘怀宝 r. M. mckay B. J. Witzke D. E. G. Briggs Iowa Department of Natural resources Geological and Water Survey 109 Trowbridge Hall Iowa City IA 52242 USA Department of Geology and Geophysics and Yale Peabody Museum of Natural History Yale University P.O. Box 208109 New Haven CT 06520 USA

Lagersttte是指保存丰富或精美化石、因而具有特殊研究价值的化石层。这类地层所含的化石常具有经矿化的生物软体甚至未变实体,从而为古生物的分类学、组织学、形态学、解剖学、生态学、埋藏学等研究提供了极其难得的材料。近年来发... 详细信息

Lagersttte是指保存丰富或精美化石、因而具有特殊研究价值的化石层。这类地层所含的化石常具有经矿化的生物软体甚至未变实体,从而为古生物的分类学、组织学、形态学、解剖学、生态学、埋藏学等研究提供了极其难得的材料。近年来发现于美国艾奥瓦州的文尼希克化石层,以其特异保存的多门类不常见化石分子为特征,成为目前仅知的中奥陶世Lagersttte。这一生物群的发现不仅填补了化石记录中的一些空白,也为中奥陶世的生物辐射事件研究领域打开了一个在赤道附近非正常海洋环境中生存的生物群面貌窗口。而且,其中所含的不同类别矿化生物残留,在有机物的分解、置换以及生物成岩作用等研究中具有重要意义。初步研究表明,文尼希克生物群的生活环境与化石保存,可能与陨石撞击事件有关,从而为奥陶纪生物辐射事件的起因可能与太空星体爆裂有关的理论研究,提供了新的验证材料。

关键词：特异埋藏文尼希克生物群圣.彼得砂岩奥陶纪生物辐射星体爆裂事件陨石坑美国艾奥瓦州

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绵羊白肝病

兽医导刊 1984年第2期 33-34页

作者： r.W:Mason r:mckay 张瑞祥

自1967年以来绵羊白肝病在新西兰就已为人们所认识。该病在这个国家多发生于春季和初夏季节,主要侵害羔羊。患病羔临床表现为食欲突然丧失,体重下降,有时出现黄疸,对光敏感（Martinoivch,1974;Sutherland氏等,1979）。根据日益积累的证... 详细信息

自1967年以来绵羊白肝病在新西兰就已为人们所认识。该病在这个国家多发生于春季和初夏季节,主要侵害羔羊。患病羔临床表现为食欲突然丧失,体重下降,有时出现黄疸,对光敏感（Martinoivch,1974;Sutherland氏等,1979）。根据日益积累的证明资料得知,绵羊白肝病的发生由于缺乏钴和维生素B;所致,还可能归

关键词：白肝病新西兰放牧场大洋洲绵羊羔羊

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皮特兰不同级进杂交猪的生产性能特性

贵州畜牧兽医科技 1983年第2期 68-74页

作者： r、M、mckay W、E、remPel 廖世碧

由两个近交系明尼苏达一号(F=0.52)和皮特兰(F=0.08)杂交后产生的118头猪,体现出皮特兰级进杂交百分率从0,25,50,62.5,75,87.5到100％。猪的应激综合症(PSS)的发生率是根据对日龄为100天左右的猪进行氟烷测验来确定的。肉质和胴体瘦肉... 详细信息

由两个近交系明尼苏达一号(F=0.52)和皮特兰(F=0.08)杂交后产生的118头猪,体现出皮特兰级进杂交百分率从0,25,50,62.5,75,87.5到100％。猪的应激综合症(PSS)的发生率是根据对日龄为100天左右的猪进行氟烷测验来确定的。肉质和胴体瘦肉量在活重为90公斤时进行测定。研究结果表明,用氟烷测验检验猪的应激综合症(PSS)可用于杂交方案的制定,采用这一方法的优点是:只要母本对应激综合症(PSS)不敏感,则杂交后所产的猪既能增加瘦肉的总产量,又不降低其生产性能。随着皮特兰血百分率的增加,在胴体长,背膘厚平均值,肉色评分和平均日增重等性能方面比明尼苏达一号猪有所降低。而背腰肉重,后腿重,眼肌面积和后腿与背腰肉百分率都是随着皮特兰血百分率的增加而直线上升。杂交猪中的皮特兰血百分率只要低于或等于50％时其应激综合症(PSS)就不存在了。测得的杂种优势为;胴体长(P<0.01),平均背膘厚(P<0.05),屠宰率(P<0.05),每公斤饲料产瘦肉量(P<0.05)。而相互间的差异是:背腰肉重(P<0.05),后腿和背腰肉百分率(P<0.05),每公斤饲料产瘦肉量(P<0.05)。这些优势只有在皮特兰作母本时才能获得。

关键词：皮特兰猪生产性能平均日增重肉色杂交猪级进杂交背膘厚性能特性

Machine Learning Techniques in Predicting Hot Deformation Behavior of Metallic Materials

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 713-732页

作者： Petr Opela Josef Walek Jaromír Kopecek Department of Metallurgical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—Institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

In engineering practice,it is often necessary to determine functional relationships between dependent and independent *** relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable ***,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely *** study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic *** ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree regression(DTr),and Gaussian Process regression(GPr)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon *** the GPr method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis.

关键词： Machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior

Emerging potential of progranulin-dependent SorCS2 signaling in healthy and diseased nervous systems

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Neural regeneration research 2025年第9期20卷 2591-2593页

作者： Alena Salasova Anders Nykjær Danish research Institute of Translational Neuroscience DANDrITE-Nordic EMBL Partnership for Molecular Medicine and Centre of Excellence PROMEMODepartment of BiomedicineAarhus UniversityAarhusDenmark

The formation of the mammalian nervous system and its maturation into sensory,motor,cognitive,and behavioral circuits is a complex process that begins during early embryogenesis and lasts until young *** neurodevelopm... 详细信息

关键词： progr jointly CS2

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A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAUrABH r.KIrAN D.SINGH r.VAISH V.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(Hr), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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Antisense oligonucleotides provide optimism to the therapeutic landscape for tauopathies

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Neural regeneration research 2025年第3期20卷 803-804页

作者： Glenn A.Harris Lauren r.Hirschfeld rainwater Charitable Foundation Fort WorthTXUSA

Tauopathies are a group of neurodegenerative diseases characterized by abnormal metabolism of the misfolded tau protein. Tau is encoded by the microtubule-associated protein tau gene(MAPT) and can be classified as either 3-repeat(3r) or 4-repeat(4r) based on the number of repeat domains from alternative splicing of exon 10 of the MAPT gene.

关键词： tau metabolism diseases

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