PURPOSE In patients with suspected giant cell arteritis (GCA), a search for the perivascular halo sign, a sophisticated color duplex ultrasound (CDU) finding, at experienced centers reliably identifies inflamed temporal arteries (TA). We tested whether TA compression in patients with GCA, a simple, largely operator-independent maneuver, elicits contrasting echogenicity between the diseased arte...

Consider a set of 6 points in R × {0, 1}: {(−1, 1), (−1, 1), (−2, 1), (−3, 0), (−3, 0), (−3, 0)}, and suppose we are interested in Prec@1. Note that the optimum model that maximizes prec@1 on these points has a positive sign. We will now show that the model w∗ ∈ R that maximizes the above structural SVM surrogate on these points has a negative sign. On the contrary, let us assume that w∗ has a ...

Surface plasmon waves in metal-dielectric-metal structures have been theoretically examined. Because of the existence of evanescent waves that can have comparable or smaller decay rates than the propagating waves, the sign of dispersion does not necessarily indicate the sign of effective refractive index for these structures. By using the direction of energy decay to distinguish the sign of ind...

Jackknife and bootstrap bias corrections are based on a diierencing argument which does not necessarily respect the sign of the true parameter value. Depending on sampling variability they can over-correct, producing a nal estimator that is negative when one knows on physical grounds that it should be positive. To overcome this problem we suggest a simple, alternative bootstrap approach, based ...

Sign patterns consisting of some positive and some negative columns, with at least one of each kind, are shown to allow any self-conjugate spectrum, and thus to allow any inertia. In the case of the n× n sign pattern with all columns positive, given any self-conjugate multiset consisting of n−1 complex numbers supplemented by a sufficiently large positive number, it is shown how to construct a ...

The birefringence of fresh and fixed mouse pancreatic acinar tissue was studied, utilizing whole mounts of pancreas from which the mesentery had been removed. Fresh pancreas in Tyrode's solution demonstrated positive birefringence with respect to the radial axis (the axis radiating from the nucleus as spokes from a wheel). Formol fixation reversed the sign of birefringence to negative with resp...

In this paper we study a nonlinear eigenvalue problem driven by the p-Laplacian. Assuming for the right-hand side nonlinearity only unilateral and sign conditions near zero, we prove the existence of three nontrivial solutions, two of which have constant sign (one is strictly positive and the other is strictly negative), while the third one belongs to the order interval formed by the two opposi...

A system to learn and recognize traffic signs is described. The system uses neural network image processing and syntactic methods. The learning process is based on the representation of traffic signs by means of a grammar, which is inferred from a set of positive and negative samples. The recognition of traffic signs in a scene is done in two steps. First, the sign is located in the scene by us...