Equal sensation for sinusoidal vibrations with an ultra-low frequency from 0.05 to 1 Hz was examined to obtain a psychological interval scale. One common empiri-cal curve of equal sensation was determined on sinusoidal whole body vibration in vertical, horizontal and inclining directions at sitting, standing and lying. The sen-sational magnitude was studied to establish a ratio scale. Thus, frequency regions of equal sensation curve between 0.5 and 300 Hz in our previous report could be extended till 0.05 Hz by the result obtained. The relation between the interval and the ratio scales for the ultra-low frequency vibration agreed with that for the vibration above 1 Hz determined previously.
The 24-hr urine was collected for five days from five adult men working in the laboratories of School of Health Sciences, University of Tokyo. The urine volume and contents of creatinine (CN), lead (Pb), cadmium (Cd), delta-aminolevulinic acid (ALA) and coproporphyrin (CP) were measured daily. (1) The inter-individual variation was statistically significant in the daily amounts of CN, CP and ALA, the urinary concentration of Pb, and the corrected concentra-tions with CN for CP and ALA by the analysis of variance. (2) In the daily amount of excretion, the metals and the urine volume were statisti-cally significantly correlated each other, but ALA is significantly correlated to CN and CP, and CP is only to ALA. (3) The individual average of the number of cigarettes per day had the significant values in the rank correlation coefficients to the urine volume, the corrected concen-tration of ALA, the corrected concentration of Pb, the daily amount of Pb per unit of body weight, the daily amount of Cd, the corrected concentration of Cd, and the daily amount of Cd per unit of body weight. By the results, the role of cigarettes smoking was discussed in relation to the urinary excretion of the metals.
Enzymatic studies on heme biosynthesis in erythroid cells of bone marrows ob-tained from ten lead workers were carried out after the establishment of methods. A remarkable reduction of the activities of δ-aminolevulinic acid (ALA) dehydrase and heme synthetase, a slight elevation of ALA synthetase activity, and a parallel reduction of 14C-glycine incorporation into heme and globin were observed. Abnor-malities found in hematological examinations and in urinary or erthrocyte porphyrin metabolism were discussed in connection with both the above mentioned results and the human response to lead. Clinical and laboratory examinations on these workers revealed a commonly exist-ing hypertension, ECG abnormalities, reduced renal functions, especially those of renal blood circulation and of renal tubules, EMG abnormalities, a reduced conduction velo-city of long nerves, and elevated concentrations of urea-N and uric acid in serum. The pathogenesis of these findings were also discussed.
Accumulation of cadmium and changes in contents of some essential metals in the livers were studied for rats receiving a single intraperitoneal injection of cadmium at 4, 14, 24 and 96 hr after the injection. Changes in intracellular distributions of these metals in the liver were also studied. Cadmium content in the liver increased with time and was about 34.2% of the injected amount at 96 hr after the injection. Calcium content in the liver showed a temporal increase by cadmium injectionand got its maximum at 14 hr after the injection. Increase of zinc and copper con-tents in the liver occured after cadmium injection. Zinc content was about 2.3 times arger than that of control level at 96 hr after cadmium injection. The increase of these metals mainly occured in the supernatant fraction. Manganese content in the liver decreased by cadmium injection, which was most remarkabe in the mitochondrial fraction. Relation between the accumulation of cadmium and the increase of zinc and copper contents in the supernatant fraction was discussed in relation to metallothionein or cadmium-binding protein.
Polyfluoroethylenepropylene (PFEP) film was pyrolysed both in air and nitrogen stream at relatively low temperature range from 350°C to 430°C. It was found by in-frared analysis that major components of the gaseous pyrolysis products were carbonyl fluoride, trifluoroacetyl fluoride, tetrafluoroethylene and hexafluoropropylene in air stream and tetrafluoroethylene and hexafluoropropylene in nitrogen stream. Hydro-lysable fluorides such as carbonyl fluoride and trifluoroacetyl fluoride were quantita-tively determined as fluorine ion content by alizarin complexone colorimetry. A profile that amount of the hydrolysable fluoride increased with pyrolysing time at each tem-perature was in fairly good agreement with the profile that amount of weight loss of PFEP increased with pyrolysing time. Amount of the weight loss of PFEP by pyrolysis was greater in air stream than in nitrogen stream. About 65% of the fluorine of PFEP was converted to the hydrolysable fluoride on the pyrolysis in air stream at the above-mentioned temperature range. Among three kinds of boat material tested, the stainless steel boat was found usable without significant loss of the hydrolysable fluoride in comparison with the repeatedly used monel boat. Amount of hydrolysable fluoride remaining on the inner wall of tube was not significantly great as compared with that produced.