BACKGROUND Recent reports using administrative claims data suggest the incidence of community- and hospital-onset sepsis is increasing. Whether this reflects changing epidemiology, more effective diagnostic methods, or changes in physician documentation and medical coding practices is unclear. METHODS We performed a temporal-trend study from 2008 to 2012 using administrative claims data and p...

This study attempts to measure neighborhood boundaries in a novel way by creating network neighborhoods based on the density of social ties among adolescents. We create valued matrices based on social ties and physical distance between adolescents in the county. We then perform factor analyses on these valued matrices to detect these network neighborhoods. The resulting network neighborhoods sh...

Following the changes in the paradigm of urban studies in recent years, sustainability has become an increasingly important issue in the neighborhood’s planning and designing. However, this concept has originally been developed for American and European neighborhoods’ planning, it could also be customized for other neighborhoods’. Additionally, in the neighborhood scale, the quality parameter f...

Locality is a standard notion of finite model theory. There are two well known flavors of it, based on Hanf’s and Gaifman’s theorems. Essentially they say that structures that locally look alike cannot be distinguished by first-order sentences. Very recently these standard notions have been generalized in two ways. The first extension makes the notion of “looking alike” depend on logical indist...

In this paper we develop a variable neighborhood search (VNS) heuristic for solving mixed-integer programs (MIPs). It uses CPLEX, the general-purpose MIP solver, as a black-box. Neighborhoods around the incumbent solution are defined by adding constraints to the original problem, as suggested in the recent local branching (LB) method of Fischetti and Lodi (Mathematical Programming Series B 2003...

A practical nurse rostering problem, which arises at a ward of an Italian private hospital, is considered. In this problem, it is required each month to generate the nursing staff shifts subject to various requirements. A matheuristic approach is introduced, based on a set of neighborhoods searched by a commercial integer programming solver within a defined global time limit. Generally speaking...

We study the nonparametric covariance estimation of a stationary Gaussian field X observed on a regular lattice. In the time series setting, some procedures like AIC are proved to achieve optimal model selection among autoregressive models. However, there exists no such equivalent results of adaptivity in a spatial setting. By considering collections of Gaussian Markov random fields (GMRF) as a...

The 2-thin part of a hyperbolic manifold, for an arbitrary positive number 2, is defined to consist of all points through which there pass homotopically non-trivial curves of length at most 2. For small enough 2, the 2-thin part is geometrically very simple: it is a disjoint union of standard neighborhoods of closed geodesics and cusps. (Explicit descriptions of these standard neighborhoods are...

Over the past few years, attention has been drawn to the importance of neighborhood influences on physical activity behavior and the need to consider a multilevel analysis involving not only individual-level variables but also social- and physical-environment variables at the neighborhood level in explaining individual differences in physical activity outcomes. This new paradigm raises a series...

BACKGROUND Administrative health databases are a valuable research tool to assess health care utilization at the population level. However, their use in obesity research limited due to the lack of data on body weight. A potential workaround is to use the ICD code of obesity to identify obese individuals. The objective of the current study was to investigate the sensitivity and specificity of an...