Laser Measurements of the H Atom + Ozone Rate Constant at Mesospheric Temperatures.

The exothermic H + O3 reaction produces OH(v) Meinel band emissions, used to derive mesospheric H concentrations and chemical heating rates. We remeasured its rate constant to reduce its uncertainty and extended the measurements to lower mesospheric temperatures using modern laser-induced fluorescence (LIF) techniques. H atoms were produced by pulsed ultraviolet laser trace photolysis of O3, followed by reaction of O((1)D) with added H2.

A nontraditional cancer support group. The Internet.

The benefits of cancer support groups (CSGs) have been well documented. Recently, several nontraditional CSGs have been used, including Internet CSGs (ICSGs). The purpose of this study was to describe categories or themes of information shared on an Internet cancer support group (ICSG), determine how many people used the list, and how frequently they posted on it.