46,713 research outputs found

    On Topologically Massive Spin-2 Gauge Theories beyond Three Dimensions

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    We investigate in which sense, at the linearized level, one can extend the 3D topologically massive gravity theory beyond three dimensions. We show that, for each k=1,2,3... a free topologically massive gauge theory in 4k-1 dimensions can be defined describing a massive "spin-2" particle provided one uses a non-standard representation of the massive "spin-2" state which makes use of a two-column Young tableau where each column is of height 2k-1. We work out the case of k=2, i.e. 7D, and show, by canonical analysis, that the model describes, unitarily, 35 massive "spin-2" degrees of freedom. The issue of interactions is discussed and compared with the three-dimensional situation.Comment: 14 pages. v2: minor changes - published versio

    Massive Three-Dimensional Supergravity From R+R^2 Action in Six Dimensions

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    We obtain a three-parameter family of massive N=1 supergravities in three dimensions from the 3-sphere reduction of an off-shell N=(1,0) six-dimensional Poincare supergravity that includes a curvature squared invariant. The three-dimensional theory contains an off-shell supergravity multiplet and an on-shell scalar matter multiplet. We then generalise this in three dimensions to an eight-parameter family of supergravities. We also find a duality relationship between the six-dimensional theory and the N=(1,0) six-dimensional theory obtained through a T^4 reduction of the heterotic string effective action that includes the higher-order terms associated with the supersymmetrisation of the anomaly-cancelling \tr(R\wedge R) term.Comment: Latex, 32 Pages, an equation is corrected, a few new equations and a number of clarifying remarks are adde

    Critical and Non-Critical Einstein-Weyl Supergravity

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    We construct N=1 supersymmetrisations of some recently-proposed theories of critical gravity, conformal gravity, and extensions of critical gravity in four dimensions. The total action consists of the sum of three separately off-shell supersymmetric actions containing Einstein gravity, a cosmological term and the square of the Weyl tensor. For generic choices of the coefficients for these terms, the excitations of the resulting theory around an AdS_4 background describe massive spin-2 and massless spin-2 modes coming from the metric; massive spin-1 modes coming from a vector field in the theory; and massless and massive spin-3/2 modes (with two unequal masses) coming from the gravitino. These assemble into a massless and a massive N=1 spin-2 multiplet. In critical supergravity, the coefficients are tuned so that the spin-2 mode in the massive multiplet becomes massless. In the supersymmetrised extensions of critical gravity, the coefficients are chosen so that the massive modes lie in a "window" of lowest energies E_0 such that these ghostlike fields can be truncated by imposing appropriate boundary conditions at infinity, thus leaving just positive-norm massless supergravity modes.Comment: 29 page

    On-shell versus off-shell equivalence in 3D gravity

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    A given field theory action determines a set of field equations but other actions may yield equivalent field equations; if so they are on-shell equivalent. They may also be off-shell equivalent, being related by the elimination of auxiliary fields or by local field redefinitions, but this is not guaranteed, as we demonstrate by consideration of the linearized limit of 3D massive gravity models. Failure to appreciate this subtlety has led to incorrect conclusions in recent studies of the ``Minimal Massive Gravity'' model

    Analysis of the essential oil from the leaves of Sesamum radiatum, a potential medication for male infertility factor, by gas chromatography - mass spectrometry

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    Essential oil was extracted from the dried leaves of Sesamum radiatum by hydro-distillation and analyzed by combined gas chromatography-mass spectrometry. n-Hexadecanoic acid was found to be the major constituent and with three other fatty acids namely, 9,12,15-octadecanoic acid-(Z,Z,Z),dodecanoic acid and tetradecanoic acid constitute 40.64% of the oil. Other constituents include heptatriacontanol, estra–1,3,5(10)–trien-17á-ol, 1-(+)–ascorbic acid, 2,6-dihexadecanoate, ethyl isoallocholate, 18,19–secoyohimban–19-oic acid, 16,17,20,21-tetrahydro-16-(hydroxymethyl)-methyl ester, (15á, 16E)-trans-(2,3-diphenylcyclopropyl) methylphenyl sulfoxide, 1,1-[2-methyl-2-(phenylthio)cyclopropylidene]bis-benzene and phenolics. The presence of some of these constituents in the essential oil provides the scientific evidences for the observed cardiovascular and estrogenic activity as well as curative properties of the plant for male infertility factor, constipation, fungal and bacterial infections and bruises

    UK Specialists’ and GDPs’ Use of Systemic and Local Antimicrobial Administration in Periodontal Therapy: A Questionnaire Study

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    Aim: The aim of the present study was to evaluate the use of antimicrobials, the prescription patterns and the reason(s) for prescribing antimicrobials when treating periodontal disease in selected UK General Dental Practitioner (GDP) and Periodontal Specialists. Materials & Methods: The questionnaire consisted of 21 questions and was sent to 488 Periodontal Specialists and 488 GDPs. Data management and analysis was performed using Microsoft Excel, SPSS® version 22.0 software and frequency distributions, cross tabulation tables and graphs were constructed from the data. Any association between variables was tested at the 5 % level of significance (P≤ 0.05). Results: The questionnaires were completed by the Specialists (38.72%) (n=189) and 23.36% (n=114) of the GDPs. The results indicated that the use of systemic and local antimicrobials followed the current guidelines. Specialists prescribed more systemic antimicrobials than the GDPs, although Specialists limited the use of local antimicrobials. The GDPs reported that decision making was difficult when to use local antimicrobials although recognised that using local antimicrobials were more effective than root surface debridement alone. Other reasons for using antimicrobials were based either on the patient request or patient satisfaction with the treatment. Lower frequency of antimicrobial use was reported in regeneration and implant procedures by both Specialists and GDPs although the Specialists were more inclined to use antibiotics/antimicrobials in these procedures. Conclusions: The results of the study suggested that there was a need for dentists to follow current guidelines when prescribing antibiotics/antimicrobials in order to avoid unnecessary prescriptions, antibiotic resistance and adverse drug reactions

    Domain walls and instantons in N=1, d=4 supergravity

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    We study the supersymmetric sources of (multi-) domain-wall and (multi-) instanton solutions of generic N=1, d=4 supergravities, that is: the worldvolume effective actions for said supersymmetric topological defects. The domain-wall solutions naturally couple to the two 3-forms recently found as part of the N=1, d=4 tensor hierarchy (i.e. they have two charges in general) and their tension is the absolute value of the superpotential section L. The introduction of sources (we study sources with finite and vanishing thickness) is equivalent to the introduction of local coupling constants and results in dramatic changes of the solutions. Our results call for a democratic reformulation of N=1,d=4 supergravity in which coupling constants are, off-shell, scalar fields. The effective actions for the instantons are always proportional to the coordinate orthogonal to the twist-free embedding of the null-geodesic (in the Wick-rotated scalar manifold) describing the instanton. We show their supersymmetry and find the associated supersymmetric (multi-) instanton solutions.Comment: 34 pages, 4 figures, references adde

    Word-level Symbolic Trajectory Evaluation

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    Symbolic trajectory evaluation (STE) is a model checking technique that has been successfully used to verify industrial designs. Existing implementations of STE, however, reason at the level of bits, allowing signals to take values in {0, 1, X}. This limits the amount of abstraction that can be achieved, and presents inherent limitations to scaling. The main contribution of this paper is to show how much more abstract lattices can be derived automatically from RTL descriptions, and how a model checker for the general theory of STE instantiated with such abstract lattices can be implemented in practice. This gives us the first practical word-level STE engine, called STEWord. Experiments on a set of designs similar to those used in industry show that STEWord scales better than word-level BMC and also bit-level STE.Comment: 19 pages, 3 figures, 2 tables, full version of paper in International Conference on Computer-Aided Verification (CAV) 201

    How useful is thrombocytosis in predicting an underlying cancer in primary care? Systematic review protocol

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    Early diagnosis of cancer is imperative to reduce the cancer burden in the UK and improve cancer survival. Identifying early markers of cancer can help general practitioners to direct patients at the greatest risk of cancer to appropriate investigative services. A raised platelet count, or thrombocytosis, has been linked to malignancy and identified as a marker of poor prognosis in secondary care, but there is little evidence around the importance of this marker in a primary care setting, within a diagnostic context. This review aims to identify and explore the body of evidence concerning the association between thrombocytosis and cancer in primary care. This protocol was produced using guidance from the PRISMA-P statement
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