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Functional origins of the vertebrate cerebellum from a sensory processing antecedent

2007中国钢铁年会

作者： david john milbourn Vanitec Winterton HouseHigh StreetWesterhamKentTN16 1AQEngland

本文研究的目的是确定不同种参数对 X65及标准工艺制备的同类管线钢的强度和韧性的影响,采用的工艺为 TM+ACC 工艺和 TM 工艺。微合金元素的影响主要研究了铌、钒、钛及三种元素混合替代的影响,同时研究了钢板厚度及不同工艺条件的影响... 详细信息

本文研究的目的是确定不同种参数对 X65及标准工艺制备的同类管线钢的强度和韧性的影响,采用的工艺为 TM+ACC 工艺和 TM 工艺。微合金元素的影响主要研究了铌、钒、钛及三种元素混合替代的影响,同时研究了钢板厚度及不同工艺条件的影响。此项研究的主要目的是确定一个经济的热轧钢板制备工艺,制备所需强度和韧性的板材,同时检测合格钢种的可焊性也非常重要。试验发现,铌、钒、钛三种元素共同微合金化的钢种具有最佳的强度和韧性的综合性能。同时发现,采用 TM+ACC 工艺制备的板材韧性优于采用 TMI 艺制备的板材。成分和工艺的最佳组合允许相对低的加热温度,以获得所需的性能。由于提高了轧钢生产速度和轧钢间歇的容许量,同样具有潜在的经济优势。可焊性测试表明,强度和韧性最佳的钢材完全满足实际要求。

关键词：管线钢微合金化钒

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Current Zoology 2010年第3期56卷 277-284页

作者： john MONTGOMERY david BODZNICK Leigh Marine Laboratory and School of Biological Sciences University of Auckland Department of Biology Wesleyan University

The structure of the cerebellar cortex is remarkably similar across vertebrate phylogeny. It is well developed in basaljawed fishes, such as sharks and rays with many of the same cell types and organizational features found in other vertebrategroups, including mammals. In particular, the lattice-like organization of cerebellar cortex (with a molecular layer of parallel fibres,interneurons, spiny Purkinje cell dendrites, and climbing fires) is a common defining characteristic. In addition to the cerebellarcortex, fishes and aquatic amphibians have a variety of cerebellum-like structures in the dorso-lateral wall of the *** structures are adjacent to, and in part, contiguous with, the cerebellum. They derive their cerebellum-like name from thepresence of a molecular layer of parallel fibers and inhibitory interneurons, which has striking organizational similarities to themolecular layer of the cerebellar cortex. However, these structures also have characteristics which differ from the cerebellum. Forexample, cerebellum-like structures do not have climbing fibres, and they are clearly sensory. They receive direct afferent inputfrom peripheral sensory receptors and relay their outputs to midbrain sensory areas. As a consequence of this close sensory association,and the ability to characterise their signal processing in a behaviourally relevant context, good progress has been made indetermining the fundamental processing algorithm in cerebellar-like structures. In particular, we have come to understand thecontribution to signal processing made by the molecular layer, which provides an adaptive filter to cancel self-generated noise inelectrosensory and lateral line systems. Given the fundamental similarities of the molecular layer across these structures, coupledwith evidence that cerebellum-like structures may have been the evolutionary antecedent of the cerebellum, we address the question:do both share the same functional algorithm? [Current Zoology 56 (3):

关键词： Origin Vertebrate Cerebellum

Characterization of the proteases in the midgut of the xylophagous larvae of Oemona hirta （Coleoptera： Cerambycidae）

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Insect Science 2009年第5期16卷 381-386页

作者： Brian david Shaw john Tane Christeller The New Zealand Institute of Plant and Food Research Palmerston North New Zealand

The protein digestive capability of the larvae of the longhorn beetle （Oemona hirta, Coleoptera： Cerambycidae, Fabricius, 1775） was investigated. This species feeds only on wood where there is a high proportion of vascular tissue. The pH of the midgut, the major digestive organ, was alkaline and protein hydrolysis was maximal at alkaline pH. Use of specific synthetic peptide substrates showed that the major protease activities were the endopeptidases, trypsin and chymotrypsin-like activity, and the exopeptidase, leucine aminopeptidase and the pH curves corresponded to that with protein substrate. Studies using a range ofserine protease inhibitors as well as specific inhibitors ofmetalloproteases, cysteine proteases and aspartate proteases confirmed a serine protease-based digestive system similar to earlier reports of sapwood-feeding Cerambycids. Control of these insect pests using protease inhibitors is discussed.

关键词： chymotrypsin digestion Oemona hirta trypsin xylophagy

Micro/nano Indentation and Single Grit Diamond Grinding Mechanism on Ultra Pure Fused Silica

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Chinese Journal of Mechanical Engineering 2011年第6期24卷 963-970页

作者： ZHAO Qingliang GUO Bing STEPHENSIN david CORBETT john School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China Materials Department Cranfield University Cranfield Bedford MK43 OAL UK School of Applied Sciences Cranfield University Cranfield Bedford MK43 OAL UK

The existing research about ductile grinding of fused silica glass was mainly focused on how to carry out ductile regime material removal for generating very ＂smoothed＂ surface and investigate the machining-induced damage in the grinding in order to reduce or eliminate the subsurface *** brittle/ductile transition behavior of optical glass materials and the wear of diamond wheel are the most important factors for ductile grinding of optical *** this paper,the critical brittle/ductile depth,the influence factors on brittle/ductile transition behavior,the wear of diamond grits in diamond grinding of ultra pure fused silica（UPFS） are investigated by means of micro/nano indentation technique,as well as single grit diamond grinding on an ultra-stiff machine tool,Tetraform ＂C＂.The single grit grinding processes are in-process monitored using acoustic emission（AE） and force dynamometer *** wear of diamond grits,morphology and subsurface integrity of the machined groves are examined with atomic force microscope（AFM） and scanning electron microscope（SEM）.The critical brittle/ductile depth of more than 0.5 μm is *** compared to the using roof-like grits,by using pyramidal diamonds leads to higher critical depths of scratch with identical grinding ***,the influence of grit shapes on the critical depth is not significant as *** grinding force increased linearly with depth of cut in the ductile removal regime,but in brittle removal regime,there are large fluctuations instead of forces *** SEM photographs of the cross-section profile show that the median cracks dominate the crack patterns beneath the single ***,The SEM photographs show multi worn patterns of diamond grits,indicating an inhomogeneous wear mechanism of diamond grits in grinding of fused silica with diamond grinding *** proposed research provides the basal technical theory for improving the ultra-precision grinding of UPFS.

关键词： ultra pure fused silica (UPFS) micro/nano indentation single grit diamond grinding ductile material removal subsurface integrity diamond grits wear

Marine invasions enter the genomic era： three lessons from the past, and the way forward

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Current Zoology 2016年第6期62卷 629-642页

作者： Frederique VIARD Patrice david john A. DARLING Sorbonne Universites UPMC Univ Paris 06 CNRS UMR 7144 Lab. Adaptation Et Diversite En Milieu Marin Team Div&Co Station Biologique De Roscoff Roscoff 29682 France CEFE UMR 5175 CNRS-Universite De Montpellier- UM III-EPFIE 1919 Route De Mende Montpellier Cedex 34293 France National Exposure Research Laboratory United States Environmental Protection Agency Research Triangle Park NC 27711 USA

The expanding scale and increasing rate of marine biological invasions have been documented since the early 20th century. Besides their global ecological and economic impacts, non-indigenous species （NIS） also have attracted much attention as opportunities to explore important eco-evolutionary processes such as rapid adaptation, long-distance dispersal and range expansion, and secondary contacts between divergent evolutionary lineages. In this context, genetic tools have been extensively used in the past 20 years. Three important issues appear to have emerged from such studies. First, the study of NIS has revealed unexpected cryptic diversity in what had previously been assumed homogeneous entities. Second, there has been surprisingly little evidence of strong founder events accompanying marine introductions, a pattern possibly driven by large propagule loads. Third, the evolutionary processes leading to successful invasion have been difficult to ascertain due to faint genetic signals. Here we explore the potential of novel tools associated with high-throughput sequencing （HTS） to address these still pressing issues. Dramatic increase in the number of loci accessible via HTS has the potential to radically increase the power of analyses aimed at species delineation, exploring the population genomic consequences of range expansions, and examining evolutionary processes such as admixture, introgression, and adaptation. Nevertheless, the value of this new wealth of genomic data will ultimately depend on the ability to couple it with expanded ＂traditional＂ efforts, including exhaustive sampling of marine populations over large geographic scales, integrated taxonomic analyses, and population level exploration of quantitative trait differentiation through common-garden and other laboratory experiments.

关键词： biological invasions cryptic species cryptogenic species eco-evolutionary processes genornics metabarcoding

Stabilization of Discrete-Time Dynamical Systems Under Event-Triggered Impulsive Control with and Without Time-Delays

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Journal of Systems Science & Complexity 2018年第1期31卷 130-146页

作者： LIU Bin HILL david john ZHANG Changfan SUN Zhijie Department of Information and Computing Science Hunan University of Technology Zhuzhou 412008 China Department of Electrical and Electronic Engineering The University of Hong Kong Hong Kong China School of Electrical and Information Engineering Hunan University of Technology Zhuzhou 412008 China Mork Family Department of Chemical Engineering and Materials Science Viterbi School of Engineering University of Southern California Los Angeles CA 90089 USA

This paper investigates the issue of stabilization for discrete-time dynamical systems（DDS）by event-triggered impulsive control（ETIC）. Based on some relatively simple threshold constants, three levels of event conditions are set and thus the ETIC scheme is designed. Three cases for ETIC with and without time-delays and data dropouts are studied respectively, and the criteria on exponential stability are derived for the controlled DDS. The stabilization in the form of exponential stability is achieved for DDS under the designed ETIC with or without time-delays. And in the case of the ETIC data dropouts, the conditions of exponential stabilization are derived for DDS and the maximal allowable dropout rates for ETIC are estimated. Finally, one example with numerical simulations is worked out for illustration.

关键词： Data dropout discrete-time dynamical systems event-triggered control exponential stability impulsive control stabilization time-delay

Low-loss microwave photonics links using hollow core fibres

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Light(Science & Applications) 2022年第8期11卷 1891-1902页

作者： Xi Zhang Zitong Feng david Marpaung Eric Numkam Fokoua Hesham Sakr john Richard Hayes Francesco Poletti david john Richardson Radan Slavík Optoelectronics Research Centre University of SouthamptonSouthamptonSO171BJUK Laser Physics and Nonlinear Optics Group Faculty of Science and TechnologyMESA+Institute for NanotechnologyUniversity of TwenteEnschede7500 AEThe Netherlands

There are a host of applications in communications, sensing, and science, in which analogue signal transmission is preferred over today’s dominant digital transmission. In some of these applications, the advantage is in lower cost, while in others, it lies in superior performance. However, especially for longer analogue photonics links (up to 10 s of km), the performance is strongly limited by the impairments arising from using standard single-mode fibres (SSMF). Firstly, the three key metrics of analogue links (loss, noise figure, and dynamic range) tend to improve with received power, but this is limited by stimulated Brillouin scattering in SSMF. Further degradation is due to the chromatic dispersion of SSMF, which induces radio-frequency (RF) signal fading, increases even-order distortions, and causes phase-to-intensity-noise conversion. Further distortions still, are caused by the Kerr nonlinearity of SSMF. We propose to address all of these shortcomings by replacing SSMFs with hollow-core optical fibres, which have simultaneously six times lower chromatic dispersion and several orders of magnitude lower nonlinearity (Brillouin, Kerr). We demonstrate the advantages in this application using a 7.7 km long hollow-core fibre sample, significantly surpassing the performance of an SSMF link in virtually every metric, including 15 dB higher link gain and 6 dB lower noise figure.

关键词： nonlinearity microwave shortcomings

Why endophenotype development requires families

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Chinese Science Bulletin 2011年第32期56卷 3382-3384页

作者： GLAHN david C BLANGERO john Department of Psychiatry Yale University School of Medicine New Haven CT 06511 USA Olin Neuropsychiatry Research Center Institute of Living Hartford Hospital CT 06106 USA Department of Genetics Texas Biomedical Research Institute San Antonio TX 78227 USA

Endophenotypes are heritable quantitative traits that are associated with disease liability, can be measured in both affected and unaffected individuals, and provide much greater power to localize and identify risk genes for mental illness than does affection status alone. Traditionally, endophenotypic markers for psychiatric illnesses include in vivo neuroanatomic and functional magnetic resonance imaging measurements and indices of neurocognitive abilities. However, neurocognitive and neuroimaging measures are by no means the only classes of endophenotypes that could be useful for identifying genes for mental illness. Given the advantages of endophenotype-based strategies for elucidating the genetic underpinnings of psychiatric disorders, it would seem prudent to develop a wide range of putative endophenotypes. In order for a measure to be considered a valid endophenotype, it must meet a number of criteria. Specifically, the trait must (1) have moderate to high heritability, (2) be associated with the illness, (3) be independent of clinical state, and (4) impairment must co-segregate with the illness within a family, with non-affected family members showing impairment relative to the general population. While each of these criteria is critical, the heritability and co-segregation requirements are really what differentiate an endophenotype from a simple biomarker. At this time, one requires an experimental design that includes families to demonstrate both heritability and co-segregation. The assertion that novel endophenotypes can not be fully established without family data does not preclude work in unrelated individuals, rather that unrelated samples will only be able to nominate potential candidate endophenotypes that subsequently need to be confirmed in family-based experiments.

关键词：家庭成员稳定精神疾病遗传基础数量性状成像测量生物标志物神经管

Antimicrobial resistance(AMR):significance to food quality and safety

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Food Quality and Safety 2019年第1期3卷 15-22页

作者： david WNelson john EMoore Juluri RRao Plant Pathology AgriFood&Biosciences Institute(AFBI)Belfast School of Biomedical Sciences Ulster UniversityColeraine Northern Ireland Public Health Laboratory Department of BacteriologyBelfast City Hospital Centre for Experimental Medicine Queen’s UniversityBelfastUK

Antibiotic resistance presents a significant challenge to clinical,veterinary,and plant health and is now recognized by the World Health Organization(WHO)as a major emerging problem of global *** yet,there have been no successful discoveries of classes of novel antibiotics since *** is an antibiotic discovery void,and it is now widely acknowledged that there is an urgent need for the development of novel antimicrobial *** economic reasons,many of the largest pharmaceutical companies have abandoned the antibiotic field,and research conducted by academia was scaled back due to funding cuts following the economic crisis.A post-antibiotic era-in which common infections and minor injuries can kill-far from being an apocalyptic fantasy,is indeed a very real possibility for the 21st century.

关键词： antibiotic antimicrobial resistance(AMR) antibiotic paradox antibiotic discovery void