Development and usage of a NIST standard reference material for real time PCR quantitation of human DNA

National Institute of Standards and Technology SRM 2372 human DNA quantitation standard has been produced to support the need for a human-specific DNA quantitation standard in forensic casework and calibration of new quantitative polymerase chain reaction (qPCR) assays. The conventional DNA concentration has been assigned with one of the U.S. National Reference UV/Visible Spectrophotometers, assuming an absorbance of 1.0 at 260 nm equals 50 ng/μL of double stranded DNA. In addition, an interlaboratory study has been conducted, to verify that the SRM 2372 materials perform well in currently used DNA quantitation assays by the forensic DNA community. Each unit of SRM 2372 consists of three well-characterized DNA extracts. Component A is a single-source human male material derived from blood. Component B is a multiple-source human female material derived from blood. Component C was purchased as a purified unsheared genomic human DNA (Sigma-Aldrich Co., St. Louis, MO) obtained as a lyophilized human genomic extract and has both male and female donors. SRM 2372 is intended to enable the comparison of DNA concentration measurements across time and place. Manufacturers can use SRM 2372 to validate the values assigned to their own reference materials. Individual forensic laboratories can use SRM 2372 to validate DNA quantitation methods and to verify the assigned concentration of in-house or commercial DNA calibration standards.     

The poverty reports,negative income taxation,and the constitution: an analysis and a compromise proposal†

Abstract. After some background discussion of the causes of and solutions to the problem of poverty, and an evaluation of the two recently published reports on this subject, the paper focuses on some political and economic constraints that are likely to be critical to the success of any proposal for a guaranteed annual income. Among these are the constitutional issue of who should control any GAI scheme, the relationship between a GAI and the present tax system, and the appropriateness of uniform guarantee levels across the nation. A compromise GAI scheme is then proposed which attempts to satisfy the relevant constraints, both economic and constitutional. Sommaire. Après une discussion préliminaire des causes de la pauvreté et de ses solutions possibles, ainsi qu'une évaluation des deux récents rapports sur le sujet, l'auteur étudie certaines contraintes politiques et économiques susceptibles de devenir des éléments critiques pour le succès de toute proposition de revenu annuel garanti. Entre autres, sont discutés, le probème constitutionnel du siège de l'autorité sur un plan de revenu annuel garanti, de la relation entre un tel plan et le présent système de taxation et de la désirabilité de niveaux unifonnes garantis à 1'échelle nationale. Enfin, un compromis est offert sous la forme d'un plan qui s'efforce de satisfaire les contraintes pertinentes de nature économique et constitutionnelle.