30,537 research outputs found

    NLO predictions for a lepton, missing transverse momentum and dijets at the Tevatron

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    n this letter we investigate the various processes that can contribute to a final state consisting of a lepton, missing transverse momentum and two jets at Next to Leading Order (NLO) at the Tevatron. In particular we consider the production of W/Z + 2 jets, diboson pairs, single top and the tt process with both fully leptonic and semi-leptonic decays. We present distributions for the invariant mass of the dijet system and normalisations of the various processes, accurate to NLO.Comment: 4 pages, 5 figure

    A note on area variables in Regge calculus

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    We consider the possibility of setting up a new version of Regge calculus in four dimensions with areas of triangles as the basic variables rather than the edge-lengths. The difficulties and restrictions of this approach are discussed.Comment: 4 pages, amstex. Revision has minor changes and more precise conclusion

    Brief for Former and Current Law Library Directors, Professors, and Academics as Amici Curiae in Support of Defendant-Appellant

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    The Copyright Act and libraries have a shared purpose: to spread knowledge to the public. See Campbell v. Acuff-Rose Music, Inc., 510 U.S. 569, 574 (1994) (noting the purpose of copyright is “[t]o promote the Progress of Science and useful Arts”). Libraries rely on balanced, careful application of the fair use balancing test to achieve that purpose. Amici respectfully submit that the District Court\u27s decision collapsed copyright law\u27s multi-part fair-use balancing test into a theory focused primarily on economics. Amici further respectfully submit that the District Court\u27s fair-use analysis was broadly applied to Internet Archive\u27s (IA) activities without distinguishing between the many different types of uses of digitized materials at issue in this case. The result in this case and the implication for future ones is that not only libraries\u27 various CDL programs but also their other longstanding, customarily permitted activities to distribute knowledge to the public could be considered commercial activities that violate copyright. A library offering standard services to connect the public to authors\u27 works, such as public read-aloud hours, while also conducting usual non-profit activities such as inviting donations through its website could suddenly be targeted for copyright infringement. In support of the IA, amici respectfully submit that this Court should vacate and remand so: (1) the District Court can separately analyze each of the actual uses of the works at issue in this case under the fair use balancing test and carefully restrict their analysis and holding to those actual uses; and (2) the District Court can appropriately weigh access to knowledge and public interest in the fair use balancing test. Amici address three points to help the Court\u27s consideration of this case. First, the District Court did not conduct the required work-by-work analysis to determine fair use and failed to account for and appropriately distinguish multiple distinct uses of digitized materials which have differing methods, purposes, and impact. Second, the District Court\u27s analysis drastically expands the definition of commerciality in the fair use balancing test. This expansion will chill many previously legitimate fair uses including by libraries as part of their mission to spread knowledge to the public. Third, this expansion of commerciality overrides the purpose of the initial Copyright Act to promote the spread of knowledge. It also counters the Copyright Act\u27s text and Congress\u27 intention to broadly define fair use to require it to be determined based on each use\u27s particular circumstances

    Influence of Planting Date and Weed Interference on Sweet Corn Growth and Development

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    Crop planting date and canopy density influence interactions between weeds and sweet corn (Zea mays L.); however, little is known about sweet corn growth response to weed interference. Field studies were conducted in 2004 and 2005 near Urbana, IL, to quantify the influence of planting date and weed interference on growth of sweet corn height, leaf area, aboveground biomass, and phenological development. Crop growth response to weed interference (presence or absence) was determined for sweet corn planted early May (EARLY) and late June (LATE). Dominant weed species included barnyardgrass [Echinochloa crus-galli (L.) Beauv.], common lambsquarters (Chenopodium album L.), common purslane (Portulaca oleracea L.), green foxtail [Setaria viridus (L.) Beauv.], redroot pigweed (Amaranthus retroflexus L.), and velvetleaf (Abutilon theophrasti Medicus) at densities ranging from 95 to 256 plants m-2. Weed interference reduced sweet corn’s absolute height growth rate, maximum leaf area index (LAI), absolute LAI growth rate, with some of the largest effects on crop growth observed in the EARLY planting date. Silk emergence was delayed by weeds for EARLY planted sweet corn, but not LATE. Moreover, the LATE planting date resulted in 9% taller crop plants with 36% lower maximum LAI. Relative to an EARLY planting date, lower yield losses due to weeds for LATE sweet corn correspond to greater resiliency of crop growth and silk emergence to weed interference

    Genome analysis of a highly virulent serotype 1 strain of streptococcus pneumoniae from West Africa

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    Streptococcus pneumoniae is a leading cause of pneumonia, meningitis, and bacteremia, estimated to cause 2 million deaths annually. The majority of pneumococcal mortality occurs in developing countries, with serotype 1 a leading cause in these areas. To begin to better understand the larger impact that serotype 1 strains have in developing countries, we characterized virulence and genetic content of PNI0373, a serotype 1 strain from a diseased patient in The Gambia. PNI0373 and another African serotype 1 strain showed high virulence in a mouse intraperitoneal challenge model, with 20% survival at a dose of 1 cfu. The PNI0373 genome sequence was similar in structure to other pneumococci, with the exception of a 100 kb inversion. PNI0373 showed only15 lineage specific CDS when compared to the pan-genome of pneumococcus. However analysis of non-core orthologs of pneumococcal genomes, showed serotype 1 strains to be closely related. Three regions were found to be serotype 1 associated and likely products of horizontal gene transfer. A detailed inventory of known virulence factors showed that some functions associated with colonization were absent, consistent with the observation that carriage of this highly virulent serotype is unusual. The African serotype 1 strains thus appear to be closely related to each other and different from other pneumococci despite similar genetic content

    A history of southern African research relevant to forensic entomology

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    Entomological forensic evidence has been used in southern Africa for decades but explicitly forensic research began in southern Africa only 26 years ago. Although applicable local research has accumulated since 1921, it is scattered in a diverse literature or unpublished. Some overseas research has also touched on local species. This review uses a historical approach to synthesize the southern African literature and to illustrate the cross-disciplinary, opportunistic nature of forensic entomology. Distinct phases of research focused on agriculture (1921-1950), medicine (1952- 1965), ecology (1968-1990) and forensics (1980-2005), but systematics spanned the entire period and tended to be ad hoc. Few scientists were involved, situated at geographically distant locations and with widely disparate research interests. The review concludes with an overview of southern African entomologists who have been involved in medico-legal investigations, and a critical evaluation of the past and future of the discipline locally

    The quantum metrology triangle and the re-definition of the SI ampere and kilogram; Analysis of a reduced set of observational equations

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    We have developed a set of seven observational equations that include all of the physics necessary to relate the most important of the fundamental constants to the definitions of the SI kilogram and ampere. We have used these to determine the influence of alternative definitions being considered for the SI kilogram and ampere on the uncertainty of three of the fundamental constants (h, e and mu). We have also reviewed the experimental evidence for the exactness of the quantum metrology triangle resulting from experiments combining the quantum Hall effect, the Josephson effects and single-electron tunnelling.Comment: 16 pages, 3 figures & 5 table

    The Nature of Nearby Counterparts to Intermediate Redshift Luminous Compact Blue Galaxies I. Optical/H I Properties and Dynamical Masses

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    We present single-dish H I spectra obtained with the Green Bank Telescope, along with optical photometric properties from the Sloan Digital Sky Survey, of 20 nearby (D < 70 Mpc) Luminous Compact Blue Galaxies (LCBGs). These ~L*, blue, high surface brightness, starbursting galaxies were selected with the same criteria used to define LCBGs at higher redshifts. We find these galaxies are gas-rich, with M(HI) ranging from 5*10^8 to 8*10^9 M_sun, and M(HI)/L_B ranging from 0.2 to 2 M_sun/L_sun, consistent with a variety of morphological types of galaxies. We find the dynamical masses (measured within R_25) span a wide range, from 3*10^9 to 1*10^11 M_sun. However, at least half have dynamical mass-to-light ratios smaller than nearby galaxies of all Hubble types, as found for LCBGs at intermediate redshifts. By comparing line widths and effective radii with local galaxy populations, we find that LCBGs are consistent with the dynamical mass properties of Magellanic (low luminosity) spirals, and the more massive irregulars and dwarf ellipticals, such as NGC 205.Comment: 33 pages, 8 figures, accepted by Ap
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