Jane Worcester

STUDIES ON THE COMBINED USE OF MEASUREMENTS OF SWEAT ELECTROLYTE COMPOSITION AND RATE OF SWEATING AS AN INDEX OF ADRENAL CORTICAL ACTIVITY

that the concentration of chloride or sodium in thermal sweat can be used as an index of that function of the adrenal cortex concerned primarily with electrolyte metabolism, studies concerning the factors which are related to or influence the electrolytic composition of sweat have gained greatly in significance. In the past, several investigators have obtained data which suggested that the concentration of chloride in sweat is positively correlated with the rate of sweating (3, 4) and skin temperature (5). However, the relations of these variables to sweat electrolyte composition have never been defined with precision nor have they been studied in connection with the effect of adrenal cortical activity on the composition of sweat. The present paper is concerned initially with studies which show that certain non-endocrine factors play a major role in the determination of sweat electrolyte composition. A method for taking these factors into consideration in the utilization of sweat electrolyte measurements as an index of hormonal activity is described. Finally investigations of adrenal cortical function based on this newly developed index are presented.

The Normal Logarithmic Transform

There are two ways of treating data which are distributed in this manner: (i) One may actually go over to the logarithms y = log x and proceed as though y were normal or nearly so; in this case m is calculated as the mean of y and ois the standard deviation of y and the usual formulas ?m = o,\Vn, uJa = o/V2n would apply. (2) Or one may fit the transform by moments on the original data, in which case the values of m and a may be somewhat different and their standard deviations will be determined by other formulas. We propose to discuss briefly some matters, connected with the logarithmic transform, which we believe have had insufficient emphasis. To make the discussion less abstract we shall give numerical illustrations obtained from the distribution of the percentage net debt (state and municipal) of the forty-eight states relative to the wealth of the state as estimated a decade

Note on factor analysis

Certain assumptions and procedures basic to factor analysis are examined from the point of view of the mathematician. It is demonstrated that the Hotelling method does not yield meaningful traits, and an example from the theory of gas mixtures with convertible components is cited as evidence. The justification of current methods for determining the adequacy of the reproduction of a correlation matrix by a factorial matrix is questioned, and ax2 criterion, practical only for a small matrix, is proposed. By means of a hypothetical example from geometry, it is shown that results of a Hotelling analysis are necessarily relative to the population at hand. The factorial effects of the adjunction of a “total test” to a group of tests are considered. Some of the general considerations and questions raised are pertinent to types of analysis other than the Hotelling.

Standards of basal metabolism of girls (new data) and their use in clinical practice

Summary 1. The metabolism of a new series of eighty-seven normal girls between the ages of ten and twenty years with exceptional economic advantages was obtained. These data were combined with that which had previously been reported by Benedict and Talbot to enlarge and modify their standards. These standards are presented. 2. It was found that the percentage deviation in normal girls may be more than plus or minus 12 per cent above or below the standards given in one-third of the cases. Therefore, too much emphasis should not be laid on minor variations outside the commonly used plus or minus 10 per cent limit. 3. Variations of between minus 12 and minus 20 per cent are receiving special study; those at the lower limit may be significant while those of less than 17 per cent probably are not. 4. Variations of more than minus or plus 20 per cent are probably significant when there is no doubt of the basality of the figures. There are indications that the progress of this study may reveal exceptions which will make an even closer correlation possible. 5. Finally, if these standards are used in other regions, they should be adjusted to the characteristics of the group of that region.

Influence of environmental temperature on resistance to endotoxin.

Summary and conclusions We have measured the mortality of mice injected with en-dotoxin at 5 environmental temperatures ranging from 18° to 33°C. At environmental temperatures 20-25 °C mice are most resistant to endotoxin, while at temperatures both above and below this range they are increasingly susceptible to it. We thank Dr. Arthur T. Hertig for generously providing laboratory space and financial support (USPH 5T1 GM 1235) for these experiments; and Dr. Lorna D. Johnson, Dr. Arthur P. Hall, and Dr. Daniel P. Mann for help in revising the manuscript.

Chronic Nonspecific Respiratory Disease in a Movie Projectionists Union: Boston, 1963–1964

A survey of 166 members (96% of those available) of a movie projectionists union in the Boston area did not reveal significant differences in respiratory symptoms of pulmonary function between those who had entered the union prior to 1940 and those who had entered the union after 1940. Measurements included responses to a standard questionnaire, and simple tests of pulmonary function. Cigarette-smoking habits were taken into account. Aerometric measurements were made in the booths and were much lower than those reported in the literature prior to 1940. As a result of this morbidity survey we do not believe that these movie projectionists have had significant exposures at work.

THE APPLICATION OF A PERSONNEL MONITORING SYSTEM TO POPULATION DOSIMETRY OF BACKGROUND RADIATION

Abstract A field study was undertaken to evaluate the use of pocket ion chamber dosimeters for measuring population dose to background radiation. The chambers were charged to a low voltage to minimize leakage and read after exposure with a pulse-reading method. The method had a sensitivity reported to be 1 mr ± 0.2 mr. Special tests were devised for selection of stable and reproducible ion chambers. The dosimeters were worn by individuals for a week at a time over a five-week period and calibrated and standardized after each week of use. Results of an analysis of variance on the standardization data obtained with 41 dosimeters over the period of use are presented. The tests showed that after field use, the system, including reader plus dosimeters, showed increased variability over the variability at the beginning of the tests. The leakage of the dosimeters was also apparently increased in field use over that found in laboratory experiments. The study showed the need of frequent testing in the field of any system used for population dosimetry at the low levels characteristic of background radiation. The design of a study of population exposure to background radiation with personnel monitoring devices is discussed. Formulas are presented for determining the total number of dosimeters to use and the number of dosimeters to assign per individual, based on initial pilot studies. The test data obtained in this survey should be useful for comparison with test data on other dosimeter systems, such as the thermoluminescent type in evaluating the performance of detection systems for the measurement of low-level population exposure.