Chemical States of Bacterial Spores: Dry-Heat Resistance

Mature bacterial spores can be manipulated by chemical pretreatments between states sensitive and resistant to dry heat. The two chemical forms of the spore differ in dry-heat resistance by about an order of magnitude. Log survivor curves for each chemical state were approximately straight lines. The temperature dependence of dry-heat resistance for each chemical state was similar to that usually found for dry-heat resistance. A method of testing spore resistance to dry heat has been designed to minimize artifacts resulting from (i) change of chemical state during the test, (ii) effects of water vapor activity, (iii) incomplete recovery of spores from the test container and clumping of spores. Implications of the existence of different chemical resistance states for experimental strategy and testing of dry-heat resistance are discussed.     

Circular deoxyribonucleic acid from Shigella dysenteriae Y6R

Circular deoxyribonucleic acid was isolated from Shigella dysenteriae Y6R and was found to consist of six species having molecular weights of 10(6), 1.3 x 10(6), 2.6 x 10(6), 3.8 x 10(6), 20 x 10(6), and 24 x 10(6) daltons. These size classes were partially resolved by sucrose density gradient centrifugation. The minicircles (10(6) and 1.3 x 10(6)) were found to have a buoyant density in CsCl of 1.710 g/ml. The 3.8 x 10(6) dalton class had a density of 1.707 g/ml. The two largest species had a density of 1.702 g/ml. Two other strains, S. sonnei II and S. dysenteriae 60, also contained circular deoxyribonucleic acid.     

Economic Aspects of “Whiplash” Injury

The term “whiplash,” used to describe a neck injury received in an automobile accident, has no foundation in medical science to support the complaints of persons suing for damages. The term is gaining unwarranted popularity as a term describing an injury, even though there are no clinical or pathological findings to support it.“Whiplash” cases today account for an estimated 30 per cent of all injuries in automobile accidents. Direct compensation for damages paid to persons injured in automobile accidents in the United States in 1961 amounted to approximately one billion, seven hundred million dollars. It has been estimated that five hundred and eighty million dollars of that amount was paid in compensation on allegation of neck injuries.     

Professional Registered Nurses in the United States and California, 1962—Report of the Bureau of Research and Planning

• Figures on professional registered nurses recently made available indicate that the ratio of active nurses to population in California in 1962 was 327 per 100,000 persons. The comparable figure nationally was 298/100,000. California ranked twentieth out of the 50 states and the District of Columbia.The percentage of all nurses actively engaged in nursing is considerably lower in California than in the total United States: 60.4 per cent compared with 65.3 per cent. This indicates that the shortage of nurses in California is more attributable to underutilization of potential manpower than to its absence.There are some identifiable categories of nurses in California in which the utilization of personnel is particularly low, as compared with other states. In terms of rates of utilization, the group of nurses over 60 years of age are most noticeably under-utilized, while in terms of numbers, married nurses could provide the greatest supply of extra nurses were their employment rate in the state equal to the national rate.The recruiting potential is a very great one, however, as this report indicates.