Using an ocean-atmosphere climate model we demonstrate that stochastic resonance could be an important mechanism for millennial-scale climate variability during glacial times. We propose that the glacial ocean circulation, unlike today's, was an excitable system with a stable and a weakly unstable mode of operation, and that a combination of weak periodic forcing and plausible-amplitude stochas...

Retinal vessels are directly accessible to clinical observation. This has numerous potential interests for medical investigations. Using the Retinal Vessel Analyzer, a dedicated eye fundus camera enabling dynamic, video-rate recording of micrometric changes of the diameter of retinal vessels, we developed a semi-automated computer tool that extracts the heart beat rate and pulse amplitude value...

Empirical reconstructions of the Northern Hemisphere (NH) temperature in the past millennium based on multiproxy records depict small-amplitude variations followed by a clear warming trend in the past two centuries. We use a coupled atmosphere-ocean model simulation of the past 1000 years as a surrogate climate to test the skill of these methods, particularly at multidecadal and centennial time...

Abstract. Mice were injected in the temporal region of the brain with cycloheximide or puromycin; both agents markedly inhibit protein synthesis in the brain. Recordings of electrical activity were made in the hippocampal region 5 hours after injection of these drugs. The amplitude and frequency observed in records from mice injected with cycloheximide were indistinguishable from those injected...

A property of nonlinear oscillators—mutual dependence between their instantaneous amplitude and frequency—is tested in the yearly and monthly records of the sunspot numbers using the histogramadjusted isospectral surrogate data and the Barnes model as the autoregressive moving average surrogates. The instantaneous amplitudes and frequencies are obtained by means of the analytic signal approach ...

Episode creation, the task of classifying medical events and related clinical data to a high-level concept, such as a disease, illness or care, has been primarily an interest of healthcare payers for purposes of cost outcomes analysis. Traditional challenges in episode creation have included: inconsistencies in defining episodes; lack of sufficient information to infer episodes; and differences...

BACKGROUND The US Preventive Services Taskforce (USPSTF) recommends routine lipid screening beginning age 35 for men [1]. For women age 20 and older, as well as men age 20-34, screening is recommended if cardiovascular risk factors are present. Prior research has focused on underutilization but not overuse of lipid testing. The objective is to document over- and under-use of lipid testing in an...

OBJECTIVE To develop and evaluate a system for reliable and efficient individualized risk-based monitoring of cholesterol and 11 other tests after kidney transplantation in children. METHODS We identified system components that drive reliable individualized monitoring and used quality improvement methods to develop and implement interventions, including (1) monitoring schedules individualized...

Episode creation describes the task of classifying medical events and related clinical data to a high-level concept, such as a disease, illness or care. Traditional approaches to the problem have been limited to feature-poor claims records utilizing simplistic strategies such as rules, filters and code transformations. However, these approaches have suffered a number of shortcomings including: ...