Porphyrins produce uniquely ephemeral animal colouration: a possible signal of virginity

Porphyrins produce uniquely ephemeral animal colouration: a possible signal of virginity

Colours that underlie animal pigmentation can either be permanent or renewable in the short term. Here we describe the discovery of a conspicuous salmon-pink colouration in the base of bustard feathers and down that has never been reported because of its extraordinarily brief expression. HPLC analyses indicated that its constituent pigments are coproporphyrin III and protoporphyrin IX, which ar...

A possible use of brown-seeded grain sorghum in animal feed

Virginity testing: a systematic review

BACKGROUND So-called virginity testing, also referred to as hymen, two-finger, or per vaginal examination, is the inspection of the female genitalia to assess if the examinee has had or has been habituated to sexual intercourse. This paper is the first systematic review of available evidence on the medical utility of virginity testing by hymen examination and its potential impacts on the examin...

A note on uniquely (nil) clean ring

A ring R is uniquely (nil) clean in case for any $a in R$ there exists a uniquely idempotent $ein R$ such that $a-e$ is invertible (nilpotent). Let $C =(A V W B)$ be the Morita Context ring. We determine conditions under which the rings $A,B$ are uniquely (nil) clean. Moreover we show that the center of a uniquely (nil) clean ring is uniquely (nil) clean.

Virginity: A contribution to the specification of

In object-oriented programs built in layers, an object at a higher level of abstraction is implemented by objects at lower levels of abstraction. It is usually crucial to correctness that a lower-level object not be shared among several higher-level objects. This paper unveils some difficulties in writing procedure specifications strong enough to guarantee that a lower-level object can be used ...