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Biomedical subjects

L H Roberts

Publications and source records attributed to L H Roberts.

4 recordsLinked to original sources
PubMed1979

Cadmium and lead pollution from secondary metal refinery operations.

A study was made of cadmium and lead levels around a small secondary metal recovery factory as part of an environmental monitoring programme in a London borough. Lead levels were essentially typical for an urban environment whereas the levels of cadmium-in-air and in household dust gave rise to very considerable concern. Some of the problems associated with assessing the potential hazard and the steps taken to control the emission are considered. It is suggested that clearly-defined standards and procedures are necessary in order to deal efficiently with similar cases as they are discovered.

Adult↗
PubMed1975

The rodent ultrasound production mechanism.

Rodents produce two types of sounds, audible and ultrasonic, that differ markedly in physical structure. Studies of sound production in light gases show that whereas the audible cries appear to be produced, as in the case of most other mammals, by vibrating structures in the larynx, the ultrasonic cries are produced by a different mechanism, probably a whistle. 'Bird-call' whistles are shown to have all the properties of rodent ultrasonic cries and to mimic them in almost every detail. Thus it is concluded that rodents have two distinct sound production mechanisms, one for audible cries and one for ultrasonic cries.

Animals↗