STUDY OBJECTIVE The objective of this study is to systematically review the accuracy of the Alvarado score and Pediatric Appendicitis Score and to identify optimal cutoffs for low- and high-risk populations. METHODS We performed a systematic review of the literature and identified 26 studies of the accuracy of the Alvarado score and Pediatric Appendicitis Score. Data were abstracted in parall...

The dynamics near a Hopf-saddle-node bifurcation of fixed points of diffeomorphisms is analysed by means of a case study: a two-parameter model map G is constructed, such that at the central bifurcation the derivative has two complex conjugate eigenvalues of modulus one and one real eigenvalue equal to 1. To investigate the effect of resonances, the complex eigenvalues are selected to have a 1:...

We investigate the cohomology of level 4 subgroup braid group, namely, kernel mod reduction Burau representation at $$t=-1$$ . This group is also equal to 2 abelianization pure group. give an exact formula for first Betti number; it a quartic polynomial in number strands. show that, like homology satisfies uniform stability sense Church and Farb. Unlike symmetries—the quotient by subgroup—is on...

An analytical equation of state (EOS) developed by Ihm-Song-Mason (ISM) has been applied tocalculate some thermophysical properties of molten polymers including Poly (1-octene) (PO), Poly (vinylmethyl ether) (PVME), Poly (vinyl chloride) (PVC), and Poly (styrene) (PS). Three temperature-dependentparameters of the ISM EOS have been determined based on the alternative scaling constants, dispersiv...

It is useful to have mathematical criteria for evaluating errors in map projections. The Chebyshev criterion for minimizing rms (root mean square) local scale factor errors for conformal maps has been useful in developing conformal map projections of continents. However, any local error criterion will be minimized ultimately by map projections with multiple interruptions. A disadvantage of inte...

Different voice qualities tend to vary in terms of their intrinsic loudness. Perceptual experiments have shown that voice quality variation can be strongly associated with the affective colouring of an utterance. The question addressed in this paper concerns the role that the intrinsic loudness variation might play in this voice quality-to-affect mapping. To test the hypothesis that the intrins...