27,912 research outputs found
Interaction of martensitic microstructures in adjacent grains
It is often observed that martensitic microstructures in adjacent polycrystal
grains are related. For example, micrographs of Arlt exhibit propagation of
layered structures across grain boundaries in the cubic-to-tetragonal phase
transformation in . Such observations are related to requirements
of compatibility of the deformation at the grain boundary. Using a
generalization of the Hadamard jump condition, this is explored in the
nonlinear elasticity model of martensitic transformations for the case of a
bicrystal with suitably oriented columnar geometry, in which the microstructure
in both grains is assumed to involve just two martensitic variants, with a
planar or non-planar interface between the grains.Comment: 6 pages, 1 figure, submitted to ICOMAT 2017 Proceeding
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Recent advances in understanding and managing chronic pelvic pain in women with special consideration to endometriosis
Chronic pelvic pain (CPP) in women is defined variably, but for clinical use it is cyclical or non-cyclical pain of at least 3-6 months' duration. It has major impacts on individuals and society. There are both structural and idiopathic causes. Whereas CPP is not curable in many cases, it is treatable. The most promising approach is multidisciplinary patient-centered care including cause-directed therapy, lifestyle changes, talking therapies, meditation, acupuncture, and physiotherapy (this is not a complete list). One of the most common structural causes for CPP is endometriosis. This review investigates current scientific concepts and recent innovations in this field as well as for CPP in general
Incompatible sets of gradients and metastability
We give a mathematical analysis of a concept of metastability induced by
incompatibility. The physical setting is a single parent phase, just about to
undergo transformation to a product phase of lower energy density. Under
certain conditions of incompatibility of the energy wells of this energy
density, we show that the parent phase is metastable in a strong sense, namely
it is a local minimizer of the free energy in an neighbourhood of its
deformation. The reason behind this result is that, due to the incompatibility
of the energy wells, a small nucleus of the product phase is necessarily
accompanied by a stressed transition layer whose energetic cost exceeds the
energy lowering capacity of the nucleus. We define and characterize
incompatible sets of matrices, in terms of which the transition layer estimate
at the heart of the proof of metastability is expressed. Finally we discuss
connections with experiment and place this concept of metastability in the
wider context of recent theoretical and experimental research on metastability
and hysteresis.Comment: Archive for Rational Mechanics and Analysis, to appea
Heavy Quark Production at High Energy
We report on QCD radiative corrections to heavy quark production valid at
high energy. The formulae presented will allow a matched calculation of the
total cross section which is correct at O(\as^3) and includes resummation of
all terms of order \as^3 [\as \ln (s/m^2)]^n. We also include asymptotic
estimates of the effect of the high energy resummation. A complete description
of the calculation of the heavy quark impact factor is included in an appendix.Comment: 32 pages (LaTeX) with three figures. Resubmission to agree with
published version, which contains a new note added in proof and modifications
of text of appendix
Scale Setting for Beyond Leading Order
We present a general procedure for applying the scale-setting prescription of
Brodsky, Lepage and Mackenzie to higher orders in the strong coupling constant
\alphas. In particular, we show how to apply this prescription when the
leading coefficient or coefficients in a series in \alphas are anomalously
small. We give a general method for computing an optimum scale numerically,
within dimensional regularization, and in cases when the coefficients of a
series are known. We find significant corrections to the scales for , , , and the ratios of
the quark pole to \MSbar and lattice bare masses.Comment: Lattice 2000 (Perturbation Theory), 5 pages, 7 figures, LaTe
Heavy baryon--light vector meson couplings in QCD
The strong coupling constants of heavy baryons with light vector mesons are
calculated in the framework of the light cone QCD sum rules using the most
general form of the interpolating currents for the heavy baryons. It is shown
that the sextet--sextet, sextet--antitriplet and antitriplet--antitriplet
transitions are described by one invariant function for each class of
transitions. The values of the electric and magnetic coupling constants for
these transitions are obtained.Comment: 16 Pages, 4 Figures and 7 Table
Curvature estimates for Weingarten hypersurfaces in Riemannian manifolds
We prove curvature estimates for general curvature functions. As an
application we show the existence of closed, strictly convex hypersurfaces with
prescribed curvature , where the defining cone of is \C_+. is only
assumed to be monotone, symmetric, homogeneous of degree 1, concave and of
class C^{m,\al}, .Comment: 9 pages, v2:final version, to be publishe
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