Upper Bound

Systematic analysis of the high recoil decay channels of the B-meson, two body mesonic decay channels in particular. For decays involving D-mesons, all experimentally observed rates are in reasonable accord with our calculations. Noticeable corrections to heavy quark symmetry are found, appearing most prominently when comparing D and D* decay modes. Calculated branching ratios involving the CKM matrix element V_{ub} are all below experimental upper bounds, but not markedly so. Calculated decay rates into charmonium lie a bit on the low side. Where color-suppressed diagrams contribute, they are found to be also suppressed dynamically and explicit calculation shows that the color-suppressed diagrams are ignorable in B to D pi decays.

The study of simple stochastic games (SSGs) was initiated by Condon for analyzing the computational power of randomized space-bounded alternating Turing machines. The game is played by two players, MAX and MIN, on a directed multigraph, and when the play terminates at a sink vertex s, MAX wins from MIN a payoff p(s)∈[0,1]. Condon proved that the problem SSG-VALUE—given a

Abstract. We give an upper bound for the Stanley depth of the edge ideal of a complete k-partite hypergraph and as an application we give an upper bound for the Stanley depth of a monomial ideal in a polynomial ring S. We also give a lower and an upper bound for the cyclic ...

To evaluate a new and simpler strategy of antibiotic prophylaxis in percutaneous endoscopic gastrostomy (PEG). Single centre, two arm, randomised, controlled, double blind clinical trial. Endoscopy unit in Karolinska University Hospital, Stockholm, Sweden, between 3 June 2005 and 31 October 2009. 234 patients with an indication for PEG who gave informed consent to participate. A single 20 ml dose of the oral solution of sulfamethoxazole and trimethoprim (also known as co-trimoxazole or Bactrim; F Hoffmann-La Roche Ltd, Basel, Switzerland) deposited in the PEG catheter immediately after insertion. The control group received standard prophylaxis consisting of a single intravenous dose of 1.5 g cefuroxime (Zinacef; GlaxoSmithKline, London) administered before insertion of the PEG tube. Primary outcome was the occurrence of clinically evident wound infection within 14 days after insertion of the PEG catheter. Secondary outcomes were positive bacterial culture and blood tests (highly sensitive C reactive protein and white blood cell count). All randomised patients were included in an intention to treat analysis. Of the 234 patients included in this study, 116 were randomly assigned to co-trimoxazole and 118 to cefuroxime. At follow-up 7-14 days after insertion of the PEG catheter, wound infection was found in 10 (8.6%) patients in the co-trimoxazole group and 14 (11.9%) in the cefuroxime group, which corresponds to a percentage point difference of -3.3% (95% confidence interval -10.9% to 4.5%). The per protocol analysis, which comprised 100 patients in each group, gave similar results-10% and 13% infection in the co-trimoxazole and cefuroxime groups, respectively (percentage point difference -3.0%, 95% CI -11.8% to 5.8%). Both these analyses indicate non-inferiority of co-trimoxazole compared with cefuroxime because the upper bounds of the confidence intervals are lower than the pre-determined non-inferiority margin of 15%. Analyses of the secondary outcomes supported this finding. 20 ml of co-trimoxazole solution deposited in a newly inserted PEG catheter is at least as effective as cefuroxime prophylaxis given intravenously before PEG at preventing wound infections in patients undergoing PEG. Trial registration Current Controlled Trials ISRCTN18677736.

We study approximation hardness of the Minimum Dominating Set problem and its variants in undirected and directed graphs. Using a similar result obtained by Trevisan for Minimum Set Cover we prove the first explicit approximation lower bounds for various kinds of domination problems (connected, total, independent) in bounded degree graphs. Asymptotically, for degree bound approaching infinity, these bounds almost match the known upper bounds. The results are applied to improve the lower bounds for other related problems such as Maximum Induced Matching and Maximum Leaf Spanning Tree.

Interest in information extraction from the biomedical literature is motivated by the need to speed up the creation of structured databases representing the latest scientific knowledge about specific objects, such as proteins and genes. This paper addresses the issue of a lack of standard definition of the problem of protein name tagging. We describe the lessons learned in developing a set of guidelines and present the first set of inter-coder results, viewed as an upper bound on system performance. Problems coders face include: ...

In this paper we describe a training method for one hidden layer multilayer perceptron classifier which is based on the idea of support vector machines (SVM's). An upper bound on the Vapnik-Chervonenkis (VC) dimension is iteratively minimized over the interconnection matrix of the hidden layer and its bias vector. The output weights are determined according to the support vector method, but without making use of the classifier form which is related to Mercer's condition. The method is illustrated on a two-spiral classification problem.

ABSTRACT The first-order South American intraplate stress field was modeled through a finite element analysis to evaluate the relative contribution of plate boundary forces and intraplate stress sources. The finite element mesh consisted of 3100 nodes in a network of 5993 equal-area triangular elements which provided a spatial resolution of about 1° at the equator. An important aspect of our modeling is the inclusion of topographic forces due to the cooling oceanic lithosphere along the Mid-Atlantic Ridge (e.g., ridge push), the continental margins along the east coast of Brazil and Argentina, and the elevated continental crust (e.g., the Andean Cordillera). Predicted intraplate stresses for two representations of the western collisional boundary forces are evaluated: pinned collisional boundaries and applied collisional boundary forces. Constraint for the modeling was provided by information about the orientation of the maximum horizontal compressive stress, SHmax, provided by 217 stress indicators from the World Stress Map Project as well as by SHmaxmagnitude estimates and torque information from previous investigations. Our modeling results demonstrate that the first-order features of the observed stress field can be explained with simple tectonic models which balance the torque acting on the plate either with a fixed western margin or drag forces applied along the base of the plate. The predicted intraplate stress field is characterized by a nearly uniform E-W SHmax orientation throughout most regions of the plate, with stress magnitudes generally less than 20 MPa averaged over a 100-km-thick lithosphere. Significant perturbation of this regional stress field occurs in the western part of the plate in response to forces associated with the high topography of the Andes. Although the magnitude of the collisional boundary forces acting along the western margin remains poorly constrained, we estimate a plausible upper bound on the force per unit length acting along the Peru-Chile Trench to be about 2.5×1012 Nm-1. While some of our models are consistent with a driving basal drag to balance the torques acting on the plate, the magnitude of the drag torque is small compared to the contribution from other sources of stress such as the ridge push force.

With respect to on-line scheduling algorithms that must direct the service of sporadic task requests we quantify the benefit of clairvoyancy, i.e., the power of possessing knowledge of various task parameters of future events. Specifically, we consider the problem of preemptively sheduling sporadic task requests in both uni- and multi-processor environments. If a task request is successfuly scheduled to completion, a value equal to the task's execution time is obtained; otherwise no value is obtained. We prove that no on-line scheduling algorithm can guarantee a cumulative value greater than 1/4th the value obtainable by a clairvoyant scheduler; i.e., we prove a 1/4th upper bound on the competitive factor of on-line real-time schedulers. We present an online uniprocessor scheduling algorithm TD 1 that actually has a competitive factor of 1/4; this bound is thus shown to be tight. We further consider the effect of restricting the amount of overloading permitted (the loading facto...

Happiness measures, reflecting individuals’ well-being, have received increasing attention by policy makers. Policies could target absolute happiness levels when aiming at increasing a society’s well-being. But given upper bounds of happiness measures, as well as the possibilities of decreasing returns to happiness resources, we argue that an important measure of interest is the efficiency with which individuals convert their resources into happiness. In order to examine the effects of policies on this efficiency and to better understand the trajectories of human well-being over time, we suggest an efficiency measure that is calculated via a nonparametric order-m approach borrowed from the production efficiency literature. Our approach is exemplified using micro level data from the British Household Panel Survey (BHPS). Between 20 and 27% of the British populace are efficient in attaining happiness during our sample period. A negative influence on “happiness efficiency” is being unemployed while a positive influence is cohabitation with a partner. Our results are robust with respect to using a more comprehensive subjective well-being measure, but there are gender differences, for example in the (positive) influence that retirement has on males’ efficiency, or the (positive) influence of maternity leave on females.

The duality between measures of economic and technical efficiency has been extensively studied in the productive efficiency analysis. This duality ensures a meaningful interpretation of technical efficiency as economic efficiency evaluated at the most favorable shadow prices. This paper concentrates on economic efficiency as short run profit efficiency. We first argue that a modified version of Varian?s goodness-of-fit measure provides

This paper deals with a novel time-interval measurement method that makes use of a surface acoustic wave (SAW) filter as a time interpolator. The method is based on the fact that a transversal SAW filter excited by a short pulse can generate a well-defined finite signal with highly suppressed spectra outside a narrow frequency band. If the responses to two

Abstract. The restricted rotation distance dR(S, T) between two binary trees S, T of n vertices is the minimum number of rotations by which S can be transformed into T, where rotations can only take place at the root of the tree, or at the right child of the root. A sharp upper bound ...

Many hard algorithmic problems dealing with graphs, circuits, formulas and constraints admit polynomial-time upper bounds if the underlying graph has small treewidth. The same problems often encourage reducing the maximal degree of vertices to simplify theoretical arguments or address practical concerns. Such degree reduction can be performed through a sequence of splittings of vertices, resulting in an expansion of the