A method based on theory has been developed for the photographic quantitation of fluorescent substances. DNA stained with ethidium in agarose gels is used as an example of an application of this method. In the course of developing this method we have demonstrated that the empirical methods employed by others authors can give rise to large systematic errors. We have also developed an approximate...

OBJECTIVE To validate a novel photographic portion guide as a tool to estimate consumption of fish and shrimp. Application of such a validated tool can facilitate accurate individual and community seafood intake assessments and provide meaningful data relative to health benefits and hazard assessment, particularly in response to environmental contamination and disasters. DESIGN A photographic...

1. Photographic mark–recapture is a cost-effective, non-invasive way to study populations. However, to efficiently apply photographic mark–recapture to large populations, computer software is needed for imagemanipulation and patternmatching. 2. We created an open-source application for the storage, pattern extraction and pattern matching of digital images for the purposes of mark–recapture anal...