4,977 research outputs found

    Not Just Cyberwarfare

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    © Springer Science+Business Media Dordrecht 2015Bringsjord and Licato provide a general meta-argument that cyberwarfare is so different from traditional kinetic warfare that no argument from analogy can allow the just war theory of Augustine and Aquinas (hereinafter called JWT) to be pulled over from traditional (modern) warfare to cyberwarfare. I believe that this meta- argument is sound and that it applies not just to cyberwarfare: in particular, on my reading of the meta-argument, argument from analogy has never been adequate to allow JWT to be applied to the kind of warfare that we are familiar with now.Peer reviewedSubmitted Versio

    Analysis of intrapulse chirp in CO2 oscillators

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    Pulsed single-frequency CO2 laser oscillators are often used as transmitters for coherent lidar applications. These oscillators suffer from intrapulse chirp, or dynamic frequency shifting. If excessive, such chirp can limit the signal-to-noise ratio of the lidar (by generating excess bandwidth), or limit the velocity resolution if the lidar is of the Doppler type. This paper describes a detailed numerical model that considers all known sources of intrapulse chirp. Some typical predictions of the model are shown, and simple design rules to minimize chirp are proposed

    The rings of n-dimensional polytopes

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    Points of an orbit of a finite Coxeter group G, generated by n reflections starting from a single seed point, are considered as vertices of a polytope (G-polytope) centered at the origin of a real n-dimensional Euclidean space. A general efficient method is recalled for the geometric description of G- polytopes, their faces of all dimensions and their adjacencies. Products and symmetrized powers of G-polytopes are introduced and their decomposition into the sums of G-polytopes is described. Several invariants of G-polytopes are found, namely the analogs of Dynkin indices of degrees 2 and 4, anomaly numbers and congruence classes of the polytopes. The definitions apply to crystallographic and non-crystallographic Coxeter groups. Examples and applications are shown.Comment: 24 page

    The application of amino acid racemization in the acid soluble fraction of enamel to the estimation of the age of human teeth

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    Estimation of age-at-death for skeletonised forensic remains is one of the most significant problems in forensic anthropology. The majority of existing morphological and histological techniques are highly inaccurate, and show a bias towards underestimating the age of older individuals. One technique which has been successful in forensic age estimation is amino acid racemization in dentine. However, this method cannot be used on remains where the post-mortem interval is greater than 20 years. An alternative approach is to measure amino acid racemization in dental enamel, which is believed to be more resistant to change post-mortem. The extent of amino acid racemization in the acid soluble fraction of the enamel proteins was determined for modem known age teeth. A strong correlation was observed between the age of the tooth and the extent of racemization. No systematic bias in the direction of age estimation errors was detected. For the majority of teeth analyzed, the presence of dental caries did not affect the results obtained. In a minority of cases, carious teeth showed a higher level of racemization than would be expected given the age of the individual. These results indicate that amino acid racemization in enamel has the potential to be used in age estimation of skeletal remains. (C) 2007 Elsevier Ireland Ltd. All rights reserved

    Simulating multiple merger pathways to the central kinematics of early-type galaxies

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    Two-dimensional integral field surveys such as ATLAS^3D are producing rich observational data sets yielding insights into galaxy formation. These new kinematic observations have highlighted the need to understand the evolutionary mechanisms leading to a spectrum of fast-rotators and slow-rotators in early-type galaxies. We address the formation of slow and fast rotators through a series of controlled, comprehensive hydrodynamical simulations sampling idealized galaxy merger scenarios constructed from model spiral galaxies. Idealized and controlled simulations of this sort complement the more 'realistic' cosmological simulations by isolating and analyzing the effects of specific parameters, as we do in this paper. We recreate minor and major binary mergers, binary merger trees with multiple progenitors, and multiple sequential mergers. Within each of these categories of formation history, we correlate progenitor gas fraction, mass ratio, orbital pericenter, orbital ellipticity, and spin with remnant kinematic properties. We create kinematic profiles of these 95 simulations comparable to ATLAS^3D data. By constructing remnant profiles of the projected specific angular momentum (lambda_R = / , triaxiality, and measuring the incidences of kinematic twists and kinematically decoupled cores, we distinguish between varying formation scenarios. We find that binary mergers nearly always form fast rotators. Slow rotators can be formed from zero initial angular momentum configurations and gas-poor mergers, but are not as round as the ATLAS^3D galaxies. Remnants of binary merger trees are triaxial slow rotators. Sequential mergers form round slow rotators that most resemble the ATLAS^3D rotators.Comment: MNRAS, in press, 12 pages, 15 figure

    Perfection of materials technology for producing improved Gunn-effect devices

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    Chemical vapor deposition system for improved Gunn effect devices using arsenic chloride 3 metho

    Assessing the Political Impacts of a Conditional Cash Transfer: Evidence From a Randomized Policy Experiment in Indonesia

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    Several developing nations, including Indonesia, have experimented with conditional cash transfers (ccts) to poor households during recent years. since 2007, Indonesia has been carrying out a randomized cct pilot program (pnpm generasi) in 1,625 villages where funds are disbursed to communities rather than households, and local councils allocate the funds to public projects following community input. in this paper, we explore political outcomes associated with the program, including electoral rewards for incumbents, and political participation. by comparing regions receiving the program with a control group, we estimate the cct\u27s effects on political behavior in the 2009 elections for president and the national legislative assembly, and we also explore its effects on local politics. we find that the cct program increases vote shares for legislative candidates from the incumbent president\u27s party, improves households\u27 satisfaction with kabupaten-level government administrative services, and decreases competition among presidential candidates as measured by the herfindahl-hirschman index (hhi). we do not find conclusive evidence to support the hypothesis that the program increases votes for the incumbent president, and we find no evidence that the program significantly increases voter turnout or affects village-level politics. keywords: conditional cash transfer, political behavior, Indonesi

    Total synthesis of the post-translationally modified polyazole peptide antibiotic plantazolicin A

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    The power of rhodium carbene methodology in chemistry is demonstrated by the synthesis of a structurally complex polyazole antibiotic. Plantazolicin A, a novel soil bacterium metabolite, comprises a linear array of 10 five-membered rings in two pentacyclic regions that derive from ribosomal peptide synthesis followed by extensive post-translational modification. The compound possesses potent antimicrobial activity, and is selectively active against the anthrax causing organism. A conceptually different synthesis of plantazolicin A is reported in which the key steps are the use of rhodium(II)-catalyzed reactions of diazocarbonyl compounds to generate up to six of the seven oxazole rings of the antibiotic. NMR Spectroscopic studies and molecular modeling, reveal a likely dynamic hairpin conformation with a hinge region around the two isoleucine residues.The compound has modest activity against methicillin-resistant Staphylococcus aureus (MRSA)
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