Publications by authors named "Ronald J Thomas"

A long-standing but fundamental question in lightning studies concerns how lightning is initiated inside storms, given the absence of physical conductors. The issue has revolved around the question of whether the discharges are initiated solely by conventional dielectric breakdown or involve relativistic runaway electron processes. Here we report observations of a relatively unknown type of discharge, called fast positive breakdown, that is the cause of high-power discharges known as narrow bipolar events.

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Objective: To evaluate the feasibility of longitudinal assessment and the psychometric properties of both established and new outcome measures used in clinical trials of patients with dementia in a cohort of Spanish-speaking elders in the United States.

Methods: This is a prospectively collected multicenter study comparing patients with Alzheimer disease (AD) (N=77) and elderly controls (N=17) who are primary Spanish speakers. Spanish-speaking individuals with AD (SSI AD) were selected to represent predefined categories of impairment as determined by a Mini-Mental State Examination score.

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