BACKGROUND So far, a few studies have tried to investigate the relationship between the placement of fixed orthodontic appliances and the change of nonmicrobial salivary properties, mostly with conflicting outcomes and short-term assessment (up to 6 months from bracket placement). The purpose of this study was to evaluate the salivary flow rate, pH and buffer capacity prior to the beginning of ...

We examine the interaction in the market for physician services when the total budget for reimbursement is fixed. Physicians obtain points for the services they render. At the end of the period the budget is divided by the sum of all points submitted, which determines the price per point. We show that this retrospective payment system involves -- compared to a fee-for-service remuneration syste...

A simple and rapid method has been developed for the determination of ascorbic acid in fruit and pharmaceutical products. The method is based on the measurement of the reaction rate between ammonium molybdate and ascorbic acid in acidic media. The reaction was monitored spectrophotometrically at 800 nm by fixed-time and variable-time methods. The calibration graph was linear in the range of...

Most functional magnetic resonance imaging (fMRI) experiments record the brain's responses to samples of stimulus materials (e.g., faces or words). Yet the statistical modeling approaches used in fMRI research universally fail to model stimulus variability in a manner that affords population generalization, meaning that researchers' conclusions technically apply only to the precise stimuli used...

Langenberg and Srinivasan (1981) proposed two procedures for the choice between two medical treatments. They assumed that there is a time lag between the administration of the treatments and the availability of the responses. The two procedures are suggested for dealing with patients who arrive during the waiting period, caused by the lag, between the trial and treatment stages of the model . T...

In this paper, we show that the early-termination fixed-complexity sphere detector (ET-FSD) has a scale effect when being employed in multi-antenna systems that have to detect signals of multiple users under the constraint of sum complexity. The so-called scale effect stands for a kind of effect in which the complexity per user can be reduced as the number of users increases without loss of div...

We present an algorithm to estimate the two-way fixed effect linear model. The algorithm relies on the Frisch-Waugh-Lovell Theorem and applies to ordinary least squares (OLS), two-stage least squares (TSLS) and generalized method of moments estimators (GMM). The coefficients of interest are computed using the residuals from the projection of all variables on the two sets of fixed-effects. Our a...

Electron capture dissociation (ECD) studies of two modified amyloid beta peptides (20-29 and 25-35) were performed to investigate the role of H* radicals in the ECD of peptide ions and the free-radical cascade (FRC) mechanism. 2,4,6-Trimethylpyridinium (TMP) was used as the fixed charge tag, which is postulated to both trap the originally formed radical upon electron capture and inhibit the H* ...

The proper analysis of experiments using language materials has been a source of controversy and debate among researchers. We summarize the main issues and discuss the solutions that have been presented. Even though the major issues have been dealt with extensively in the literature, there still exists quite a bit of confusion about how to analyze the data from such experiments. We discuss a nu...