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David R. Smith

Bio: David R. Smith is an academic researcher from Duke University. The author has contributed to research in topics: Metamaterial & Antenna (radio). The author has an hindex of 110, co-authored 881 publications receiving 91683 citations. Previous affiliations of David R. Smith include Brunel University London & Princeton University.


Papers
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Proceedings ArticleDOI
TL;DR: The Chandrayaan-1 X-ray Spectrometer (C1XS) as discussed by the authors is a two-year mission in lunar orbit conducting mineralogical surface mapping over the range of 1 -10 keV.
Abstract: The Chandrayaan-1 X-ray Spectrometer (C1XS) will be launched as part of the Indian Space Research Organisation (ISRO) Chandrayaan-1 payload in September 2008, arriving at the Moon within 7 days to begin a two year mission in lunar orbit conducting mineralogical surface mapping over the range of 1 – 10 keV. The detector plane of the instrument consists of twenty four e2v technologies CCD54 swept-charge devices (SCDs). Such devices were first flown in the Demonstration of a Compact Imaging X-ray Spectrometer (D-CIXS) instrument onboard SMART-1 [4, 5]. The detector plane in each case provides a total X-ray collection area of 26.4 cm 2 . The SCD is capable of providing near Fano-limited spectroscopy at -10 o C, and at -20 o C, near the Chandrayaan-1 mission average temperature, it achieves a total system noise of 6.2 electrons r.m.s. and a FWHM of 134 eV at Mn-Kα. This paper presents a brief overview of the C1XS mission and a detailed study of the effects of proton irradiation on SCD operational performance.

6 citations

Journal ArticleDOI
M. Ono1, M. G. Bell1, R. E. Bell1, S. Bernabei1, J.M. Bialek2, T.S. Bigelow3, Manfred Bitter1, T. M. Biewer4, W. R. Blanchard1, J. Boedo5, C.E. Bush3, J. Chrzanowski1, D.S. Darrow1, L. Dudek1, R. Feder1, J.R. Ferron6, J. Foley, E.D. Fredrickson1, D.A. Gates1, G. Gettelfinger1, T. Gibney1, R. W. Harvey7, R. Hatcher1, W. Heidbrink5, Thomas Jarboe8, David W. Johnson1, M. Kalish1, R. Kaita1, Stanley Kaye1, C. E. Kessel1, S. Kubota5, H.W. Kugel1, G. Labik1, B. LeBlanc1, K. C. Lee5, Fred Levinton, J. L. Lowrance1, Rajesh Maingi3, J. Manickam1, R.J. Maqueda, R. Marsala1, D. Mastravito1, E. Mazzucato1, S. S. Medley1, J.E. Menard1, D. Mueller1, Tobin Munsat9, Brian Nelson8, C. Neumeyer1, Nobuhiro Nishino10, Hyeon K. Park1, S. F. Paul1, T. Peebles5, E. Perry1, Yueng Kay Martin Peng3, C. K. Phillips1, R.I. Pinsker6, S. Ramakrishnan1, Roger Raman8, P. Roney1, A. L. Roquemore1, P.M. Ryan3, S.A. Sabbagh2, H. Schneider1, C.H. Skinner1, David R. Smith1, Aaron Sontag2, Vlad Soukhanovskii11, T. Stevenson1, D. P. Stotler1, Brentley Stratton1, Dan Stutman12, D.W. Swain3, E. J. Synakowski1, Yuichi Takase13, G. Taylor1, Kevin Tritz12, A. von Halle1, John B Wilgen3, M. Williams1, J. R. Wilson1, I. Zatz1, W. Zhu2, S. J. Zweben1, R.J. Akers14, Peter Beiersdorfer11, P.T. Bonoli4, Clarisse Bourdelle, Mark D. Carter3, Choong-Seock Chang15, Wonho Choe, W. Davis1, S. J. Diem1, C. Domier1, Richard Ellis1, P. C. Efthimion1, A. R. Field14, Michael Finkenthal12, E. Fredd1, Guoyong Fu1, Alan H. Glasser16, Robert James Goldston1, L. R. Grisham1, N.N. Gorelenkov1, Luca Guazzotto17, R. J. Hawryluk1, P. J. Heitzenroeder1, K. W. Hill1, Wayne A Houlberg3, J.C. Hosea1, D.A. Humphreys6, C. Jun1, Jayhyun Kim, S. Krasheninnikov5, L.L. Lao6, S. G. Lee, J. Lawson1, N. C. Luhmann1, T. K. Mau5, M.M. Menon3, Osamu Mitarai18, Masayoshi Nagata, G. Oliaro1, D. Pacella19, R. Parsells1, A. Pigarov5, G.D. Porter11, Abhay K. Ram4, David A Rasmussen3, M. H. Redi1, G. Rewoldt1, J. Robinson1, E. Ruskov5, J. Schmidt1, I. Semenov, Ker-Chung Shaing20, K. Shinohara, M.J. Schaffer6, P. Sichta1, Xian-Zhu Tang16, J. Timberlake1, M. R. Wade3, William R. Wampler21, Zhehui Wang16, R. Woolley1, G. A. Wurden16, Xueqiao Xu11 
TL;DR: An overview of the research capabilities and the future plans on the MA-class National Spherical Torus Experiment (NSTX) at Princeton is presented in this paper, where the authors describe the Next-Step-ST (NSST) device being designed to address these issues in fusion-relevant plasma conditions.
Abstract: An overview of the research capabilities and the future plans on the MA-class National Spherical Torus Experiment (NSTX) at Princeton is presented. NSTX research is exploring the scientific benefits of modifying the field line structure from that in more conventional aspect ratio devices, such as the tokamak. The relevant scientific issues pursued on NSTX include energy confinement, MHD stability at high beta, non-inductive sustainment, solenoid-free start-up, and power and particle handling. In support of the NSTX research goal, research tools are being developed by the NSTX team. In the context of the fusion energy development path being formulated in the US, an ST-based Component Test Facility (CTF) and, ultimately a high beta Demo device based on the ST, are being considered. For these, it is essential to develop high performance (high beta and high confinement), steady-state (non-inductively driven) ST operational scenarios and an efficient solenoid-free start-up concept. We will also briefly describe the Next-Step-ST (NSST) device being designed to address these issues in fusion-relevant plasma conditions.

6 citations

Journal ArticleDOI
TL;DR: In this paper, the authors proposed a method to generate semicrystalline distributions of particles where the lattice constant of the distribution is an arbitrary function of position, and applied it to the design and implementation of a microwave gradient index lens.
Abstract: For many applications in gradient index devices and photonic crystals, it is necessary to be able to design semicrystalline distributions of particles where the lattice constant of the distribution is an arbitrary function of position We propose a method to generate such distributions which is physically motivated by a system of interacting particles, and apply it to the design and implementation of a microwave gradient index lens While the demonstration was preformed at microwave wavelengths, this technique would also be particularly useful for designing devices for operation at IR and visible wavelengths where the fabrication of distributions of uniformly sized holes or columns is very easy

6 citations

Proceedings ArticleDOI
04 Mar 2008
TL;DR: In this article, effective gradient index (EGI) devices are fabricated to collimate and steer microwave beams by designing the spatial profile of positive effective permittivity across the slab, and large steering angles of up to 22 degrees with only 0.7 dB transmission loss are demonstrated.
Abstract: We have demonstrated that effective gradient index devices can be fabricated to collimate and steer microwave beams by designing the spatial profile of positive effective permittivity across the slab. Resonant losses in the devices is reduced dramatically by operating at frequency ranges far from the unit cell resonance, and substrate losses is reduced by utilizing low loss material. Using these approaches, we demonstrate large steering angles of up to 22 degrees with only 0.7 dB transmission loss. These pave the way for practical implementation of low-cost microwave beam steering devices using metamaterials.

6 citations

Journal ArticleDOI
TL;DR: It is found that changes in spatial localization produced by surgery on the operated eye paralleled those found in the other eye, both in magnitude and duration.
Abstract: We measured spatial localization (using an open-loop pointing task) monocularly in each eye of eight patients undergoing unilateral strabismus surgery. Most of these patients had some degree of binocular vision. We found that, in most cases, changes in spatial localization produced by surgery on the operated eye paralleled those found in the other eye, both in magnitude and duration. Unilateral surgery can have central effects on egocentric localization.

6 citations


Cited by
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Journal ArticleDOI

[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal ArticleDOI
TL;DR: A review of gold nanoparticles can be found in this article, where the most stable metal nanoparticles, called gold colloids (AuNPs), have been used for catalysis and biology applications.
Abstract: Although gold is the subject of one of the most ancient themes of investigation in science, its renaissance now leads to an exponentially increasing number of publications, especially in the context of emerging nanoscience and nanotechnology with nanoparticles and self-assembled monolayers (SAMs). We will limit the present review to gold nanoparticles (AuNPs), also called gold colloids. AuNPs are the most stable metal nanoparticles, and they present fascinating aspects such as their assembly of multiple types involving materials science, the behavior of the individual particles, size-related electronic, magnetic and optical properties (quantum size effect), and their applications to catalysis and biology. Their promises are in these fields as well as in the bottom-up approach of nanotechnology, and they will be key materials and building block in the 21st century. Whereas the extraction of gold started in the 5th millennium B.C. near Varna (Bulgaria) and reached 10 tons per year in Egypt around 1200-1300 B.C. when the marvelous statue of Touthankamon was constructed, it is probable that “soluble” gold appeared around the 5th or 4th century B.C. in Egypt and China. In antiquity, materials were used in an ecological sense for both aesthetic and curative purposes. Colloidal gold was used to make ruby glass 293 Chem. Rev. 2004, 104, 293−346

11,752 citations

Journal ArticleDOI
14 Aug 2003-Nature
TL;DR: By altering the structure of a metal's surface, the properties of surface plasmons—in particular their interaction with light—can be tailored, which could lead to miniaturized photonic circuits with length scales that are much smaller than those currently achieved.
Abstract: Surface plasmons are waves that propagate along the surface of a conductor. By altering the structure of a metal's surface, the properties of surface plasmons--in particular their interaction with light--can be tailored, which offers the potential for developing new types of photonic device. This could lead to miniaturized photonic circuits with length scales that are much smaller than those currently achieved. Surface plasmons are being explored for their potential in subwavelength optics, data storage, light generation, microscopy and bio-photonics.

10,689 citations

Journal ArticleDOI
01 Apr 1988-Nature
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

9,929 citations