Existing guidelines for the number of ultrasounds required before clinical competency are based not on scientific study but on consensus opinion. The objective of this study was to describe the learning curve of limited right upper quadrant ultrasound. This was a prospective descriptive study. Ultrasounds collected over 1 year were reviewed for interpretive and technical errors. Possible errors...

BACKGROUND Selecting controls that match cases on risk factors for the outcome is a pervasive practice in biomarker research studies. Such matching, however, biases estimates of biomarker prediction performance. The magnitudes of these biases are unknown. METHODS We examined the prediction performance of biomarkers and improvements in prediction gained by adding biomarkers to risk factor info...

Accurate diagnosis of disease is a critical part of health care. New diagnostic and screening tests must be evaluated based on their abilities to discriminate diseased from nondiseased states. The partial area under the receiver operating characteristic (ROC) curve is a measure of diagnostic test accuracy. We present an interpretation of the partial area under the curve (AUC), which gives rise ...

Two fundamental questions dealing with simultaneous hermaphrodites are how resources are optimally allocated to the male and female function and what conditions determine shifts in optimal sex allocation with age or size. In this study, I explored multiple factors that theoretically affect fitness gain curves (that depict the relationship between sex-specific investment and fitness gains) to pr...

punitive damage is a kind of supra-compensatory damage which is awarded in favor of plaintiff in civil actions for punishing the defendant and deterring him from taking action like that in future. the main feature of punitive verdict is deterrence and punishment and in this regard two economic theories exist (optimal deterrence and gain elimination theories). however punitive aspect of this dam...

co-channel interference is a major factor in limiting the capacity and link quality in cellular communications. as the co-channel interference is modeled by lognormal distribution, sum of the co-channel interferences of neighboring cells is represented by the sum of lognormal random variables (rvs) which has no closed-form expression. assuming independent, identically distributed (iid) rvs, the...

We investigated analytical structure of the Takagi–Sugeno (TS) type of fuzzy controllers, which was unavailable in the literature. The TS fuzzy controllers we studied employ a new and simplified TS control rule scheme in which all the rule consequent use a common function and are proportional to one another, greatly reducing the number of parameters needed in the rules. Other components of the ...

In this paper, we present a novel scheme for parsing images into medium level vision representation: contour curve and region texture. This scheme is integrated with piecewise iterative curve fitting and texture synthesis, in which an original image is analyzed at the representation side so as to obtain contours and local texture exemplars. The contour of each region will be processed piecewise...

Using a femtosecond three-pulse pump-probe technique, we investigated spectral hole-burning and gain recovery dynamics in self-organized In~Ga!As quantum dots. The spectral hole dynamics are qualitatively different from those observed in quantum wells, and allow us to distinguish unambiguously the gain recovery due to intradot relaxation and that due to carrier capture. The gain recovery due to...

Subdivision provides an efficient method to generate smooth curves and surfaces. Recently matrixvalued subdivision schemes were introduced to provide more flexibility and smaller subdivision templates for curve and surface design. For matrix-valued subdivision, the input is a set of vectors with the first components being the vertices of the control polygon (or the control net for surface subdi...