The influence of sulfhydryl on the formation of aberrant disorganized overgrowths in the regenerating right chela of the hermit crab (Pagurus Longicarpus)

Conclusions Sulfhydryl accelerates and sulfoxide retards the growth, differentiation, and expression of trend to organization of aberrant disorganized overgrowths emerging from tear lesions arising from injury to the regenerating chelae of the Hermit crab.Sulfhydryl is specifically responsible for the formation of certain typical emergent disorganized growths from the distal end of the Hermit crab chela.The material for this study was collected at the Marine Experimental Station of The Research Institute of the Lankenau Hospital at North Truro, Massachusetts, under grants from Mr.August Bein of Philadelphia, and the Capt. L. D.Baker Estate of Boston and Wellfleet.     

Auditory Perception

Auditory perceptual tasks involving the discrimination of fine differences in frequency, duration, or rhythmic pattern were given to a group of sixth form schoolboys. The results indicate that there is a wide range of auditory skills for different individuals, even within a relatively homogeneous group. There are also differences in a person''s ability to carry out distinct tasks; there does not necessarily appear to be any correlation between his ability for each task.The findings support observations arising out of consideration of hearing problems in children and adults that pure tone threshold audiometry and its derivatives give an inadequate definition of hearing disorder and a limited understanding of the nature of hearing.     

Effects of Selenium Compounds on Formate Metabolism and Coincidence of Selenium-75 Incorporation and Formic Dehydrogenase Activity in Cell-Free Preparations of Escherchia coli

Wild-type sex factors of Escherichia coli K-12 can be cured from host cells by growth at temperatures above 42 C. This phenomenon is obscured by reinfection of cured cells if the culture is allowed to reach cell densities above 10(5)/ml. The rate of episome loss is dependent on the genetic (chromosomal) background of the host.