Comparison of conventional and simulated reduced-tube current MDCT for evaluation of suspected appendicitis in the pediatric population.

Objective: The purpose of this study was to compare CT with conventional and simulated reduced-tube current in the evaluation for acute appendicitis in children.

Materials And Methods: Validated noise-addition (tube current-reduction) software was used to create 50% and 75% tube current reductions in 60 CT examinations performed for suspected appendicitis, resulting in 180 image sets. Three blinded pediatric radiologists scored the randomized studies for the following factors: presence of the normal appendix or appendicitis (5-point scale; 1=definitely absent and 5=definitely present), presence of alternate diagnoses, and overall image quality (1=nondiagnostic and 5=excellent).

Regionally autonomous segmentation within zebrafish presomitic mesoderm.

Similar to chick, mouse, and Xenopus, a number of intercellular signaling pathways are required for zebrafish segmentation. However, the spatial scales over which these signaling pathways operate in zebrafish remain largely unknown. During zebrafish segmentation, waves of her1 transcription (a) initiate within the tailbud region, (b) propagate anteriorly through presomitic mesoderm (PSM), and (c) terminate in the anlage of newly-forming somites.

The Zebrafish DVD Exchange Project: a bioinformatics initiative.

Scientists who study zebrafish currently have an acute need to increase the rate of visual data exchange within their international community. Although the Internet has provided a revolutionary transformation of information exchange, the Internet is at present unable to serve as a vehicle for the efficient exchange of massive amounts of visual information. Much like an overburdened public water system, the Internet has inherent limits to the services it can provide.