The characterization of measurement error is critical in assessing the significance of diffusion tensor imaging (DTI) findings in longitudinal and cohort studies of psychiatric disorders. We studied 20 healthy volunteers, each one scanned twice (average interval between scans of 51 +/- 46.8 days) with a single shot echo planar DTI technique. Intersession variability for fractional anisotropy (F...

A method for predicting the interindividual variability of human exposure for CYP3A4 substrates using Monte Carlo simulation was developed based on relevant factors. The coefficient of variation (CV) values for CYP3A4 content in human liver microsomes, hepatic blood flow, liver volume and body weight, and the unbound blood fraction were collected from the published literature. The parallel tube...

In this paper, we present a novel concept for optical beam-guidance to significantly enhance the sensitivity of colorimetric assays by extending the optical path length through the detection cell which linearly impacts the resulting attenuation of a probe beam according to the law of Beer-Lambert. In our setup, the incident probe beam is deflected by 90( composite function) into the chip plane ...

BACKGROUND The basis for this study is the fact that instrument error increases the variance of the distribution of body mass index (BMI). Combined with a defined cut-off value this may impact upon the estimated proportion of overweight and obesity. It is important to ensure high quality surveillance data in order to follow trends of estimated prevalence of overweight and obesity. The purpose o...

The Comet assay (CA) is a sensitive/simple measure of genotoxicity. However, many features of CA contribute variability. To minimize these, we have introduced internal standard materials consisting of 'reference' cells which have their DNA substituted with BrdU. Using a fluorescent anti-BrdU antibody, plus an additional barrier filter, comets derived from these cells could be readily distinguis...

PURPOSE To evaluate the variation in higher-order ocular wavefront aberrations and the Nyquist limit of resolution of the cone mosaic (N(c)) in a population of young healthy subjects and the relation to axial length (AL). SETTING Fondazione G.B. Bietti IRCCS, Rome, Italy. DESIGN Case series. METHODS An adaptive optics retinal camera prototype (rtx1) was used to image the cone mosaic. Cone...

Clinical trials of analgesics have been plagued with poor assay sensitivity due, in part, to variability in subjects' pain reporting. Herein, we develop and evaluate the focused analgesia selection test (FAST), a method to measure patients' pain reporting skills. Subjects with osteoarthritis of the hip, knee, and/or ankle with pain intensity of ≥3/10 on a 0-10 numerical rating scale were enroll...

Analyses of survival data of a mixture of Salmonella spp. at fixed temperatures between 55 degrees C (131 degrees F) and 71.1 degrees C (160 degrees F) in ground beef matrices containing concentrations of salt between 0 and 4.5%, concentrations of sodium pyrophosphate (SPP) between 0 and 0.5%, and concentrations of sodium lactate (NaL) between 0 and 4.5% indicated that heat resistance of Salmon...

Purpose. To determine the repeatability of recalculated corneal visualization Scheimpflug technology (CorVis ST) parameters and to study the variation of biomechanical properties and their association with demographic and ocular characteristics. Methods. A total of 783 healthy subjects were included in this study. Comprehensive ophthalmological examinations were conducted. The repeatability of ...

The aim of this study was to translate and test the psychometric properties of a Farsi and an English version of the spiritual needs questionnaire (SpNQ) a measure originally developed in German. The World Health Organization guideline for translating and validating questionnaires was used. Participants were recruited from hospitals in Iran and New Zealand during an outpatient follow-up appoint...