Mitchell and Seiden\u27s Reviewing the academic library: A guide to selfstudy and external review (Book Review)

A review of Mitchell, E., & Seiden, P. (Eds.) (2015). Reviewing the academic library: A guide to selfstudy and external review. Chicago: ACRL. 334 pp. $65.00. ISBN 978083898783

Roofing Materials

Describes some of the many materials and systems available for residential roofing, typical application details and some of the problems encountered. Included are properties of roofing types, including shingles and rolled roofing, and selection of materials

Some of the oxidation-reduction properties of the chorionic gonadotropic hormone

Gurin, Bachman, and Wilson (1-3) have recently made important contributions to our knowledge of the chemical nature of the gonadotropic hormone of pregnancy urine. They have given a method for the preparation of the hormone in a highly purified form and have described many of its outstanding chemical and physical properties. We have been especially interested in the reference of these authors to the unexplained, continuous, and apparently spontaneous inactivation of their highly purified material which takes place, particularly in aqueous solution, without, detectable loss or rupture of certain portions of the molecule (3). Earlier communications (4-6) have called attention to our observations relative to the oxidation and inactivation of a reducing factor of pregnancy urine which appears to be the chorionic gonadotropic hormone. Some of our more recent findings appear to shed light upon the observations of the above authors. The spontaneous oxidation of this reducing factor proceeds at a very slow rate but is more rapid in aqueous solution than in urine, where other stronger reducing agents tend to protect it. If activating agents are added and moderate heat is applied, the activity becomes of sufficient magnitude to bring about the reduction of dilute solutions of iodine or other oxidants. The object of this paper is to describe some of the rather unusual characteristics of this oxidation-reduction system

The Knowlton-Graham partition problem

A set partition technique that is useful for identifying wires in cables can be recast in the language of 0--1 matrices, thereby resolving an open problem stated by R.~L. Graham in Volume 1 of this journal. The proof involves a construction of 0--1 matrices having row and column sums without gaps