By using the Cascade Impactor the authors collected 600l of air sample per day, at the roof of the School of Pharmaceutical Science, Toho University, Funabashi, Chiba Prefecture. Each air sampling, which had been taken for about two hrs, is repeated three times per week for two years, beginning January 1969.
The atmospheric pollens were recovered from the Cascade Impactor, and the number of pollens per each samples were counted under the microscope, identifying the species of pollens.
Six types of species were classified according to the classification of pollens in Japan reported by Dr. M. Ikuse. The accumulated number of pollens per each species per day i.e., per air samples, were plotted on the ordinate of Weibull Probability Paper, on the abscissa of which the day of measurement was shown, as an elapse of days from the first day of appearence of the pollens concerned.
The following results were obtained:
1) The author has already reported in the previous paper that the number of pollen per unit volume of air do not follow the Normal Curve. The Weibull Paper without assuming the Normal Curve, revealed to be suitable to show the seasonal variation of the number of pollens in air.
2) The Weibull Paper, on the logarithmic scale, is suited to show the details of the begining of emission of pollens.
3) By using the Weibull Paper, it is possible, to separate the compound distribution composed of more than two species of pollens into the original distributions.

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The mode of occurrence of the scalds and burns was statistically compiled as data to be used in the prevention of accidents, using findings from 1379 victims who were taken to the hospital by ambulance in the wards of Tokyo in 1976. Sixty-one percent of the victims were scalded by hot liquids, and 22 percent received burns by direct contact with flames. Other such accidents happened in a variety of ways; for example, by touching an iron or the stove, from gas explosions, flash burns from fireworks, electric burns and chemical burns. In the case of scalds caused by hot liquids involving dishes, cups, kettles, pots and thermos bottles, young children seemed particularly accident prone; it was found that 648 per 1, 000, 000 were injured in groups of children aged four or less. Injury of torso increased in young children, and it tended to be serious. The age groups of 5 to 9 and 20 to 29 also ran the risk of scalds caused by hot liquids. With fire and flame indoors, findings revealed that persons over age 60 were injured twice or more as often as those in other age groups. Young children and old persons showed peaks in the area of burns from hot metal objects. Winter season and evening were other time factors in the accidents, and especially many scalds due to hot liquids occurred in the evening. To reduce scalds and burns, improvements are called for in kitchen equipment and in the heating system. More case is essential to prevent these hazards.

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This study was undertaken to clarify the effect of aggregate life on the adrenocortical function. Adrenal weight, and 11-OHCS concentration in the adrenal gland and the serum were measured on Wistar rats. The experiment consists of the following two parts.
Experiment 1. The influences of group size and occupied space per rat on the adrenocortical function were observed. Immediately after weaning, the rats were divided into five groups by the group size and the occupied space, and then were reared for 50 days. The following results were obtained.
The aggregate life caused an increase in the adrenocortical function. The group size had more influence on this increase than on the occupied space, especially in a small occupied space. And females showed the adrenocortical function to be higher than males. And furthermore, as for the group size, the adrenocortical function in two rats per cage was lowest in females.
Experiment 2. The relationship between the adrenocortical function and the social rank in a group was investigated. This experiment was carried out on 3 rats per cage. The social rank in a group was evaluated by the profiles based on the number of fights and the rate of victory.
From the results, subordinate rats showed the adrenocortical function higher than dominant rats.

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Male rats were exposed to the wide octave-band noise for eight hours at the intensity of 60, 80, or 100dB (C), respectively. The 11-OHCS concentration in the adrenal glands increased in the initial stage of noise exposure, and returned to the control level soon after. The circadian rhythm of 11-OHCS remained in spite of the continuation of noise exposure except in the initial response. After the noise exposure, rats were exposed again at 100dB (C). The 11-OHCS did not increase in the rats exposed previously at 100dB (C). In all the intensities, the 11-OHCS increased to the control level by ACTH administration at the end of noise exposure. By histamine administration at the end of noise exposure, the increase of the 11-OHCS was less in the rats exposed to 100dB (C) than in the rats exposed to low intensities.

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The purpose of these papers (Part 1, Part 2) is to clarify the temporary threshold shift (=TTS) of human vibratory sensation after localized vibration exposure and to take data for hygienic allowable limit of vibration of portable mechanized tool.
Part 1 was a preparatory experiment on the methods of vibration exposure and vibratory sensation measurement. In this Part 1, five healthy subjects were exposed to six kinds of vibration, the frequencies of which were 31.5, 125 and 500Hz, respectively, and each acceleration which was 1g or 5g (Fig. 2).
Each subject put his right hand on the vibrator plate in a relaxed sitting posture and was exposed with sinusoidal vibration (Fig. 1). Vibratory sensation thresholds (63Hz, 125Hz, 250Hz) at the fingertip were measured before and after the vibration exposure. The skin temperature on the back side of the same finger, which was considered to effect the vibratory sensation threshold, was also measured.
The room temperature was kept at 20∼23°C during the experiment.
In this paper, vibratory sensation threshold and exposed vibration were expressed with peak values of acceleration.
The result was as follows:
1. The accumulation effect of vibratory sensation threshold owing to repeated vibration exposure was eliminated by the 15min. rest and some exercises of four extrimities between the serious vibration exposure (Fig. 3).
2. Variations of the skin temperature owing to vibration exposure were not so great. Therefore, it was considered that the effect of the skin temperature on the vibratory sensation threshold was negligible in the method used in this experiment (Table 1).
3. After vibration exposure, increases of vibratory sensation thresholds were statisticaly significant on the exposed side. And, the values of TTS of vibratory sensation were affected by the frequency and acceleration level of exposed vibration. But, the increase of vibratory sensation threshold was not clearly observed on the unexposed side (Table 1).
4. After vibration exposure, TTS of vibratory sensation decreased almost linealy with the logarithm of the time (Fig. 4). Therefore, it was considered that prompt measurement after vibration exposure is necessary to obtain an exact value of TTS. On this point, the measurement method of vibratory sensation threshold in this experiment was available.

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The following experiment of vibration exposure was performed with a similar method on the basis of the result of the preliminary study in Part 1. The purpose of this study is to clarify in detail the relationship between the temporary threshold shift (=TTS) of vibratory sensation and the frequency and severity of exposed vibration.
In this case, six subjects, all healthy students, were exposed to localized vibration, which frequencies and levels of acceleration referred to exposure boundary of ISO (1973) (Table 1).
In this paper, vibratory sensation threshold was expressed with peak value of acceleration and exposed vibration with peak value of acceleration, velocity or amplitude.
The result was as follows:
1. TTS of vibratory sensation, immediately after vibration exposure of equal velocity level, showed maximum values at 250Hz exposure and smooth curves from 8Hz to 1, 000Hz exposure. On the vibration exposure of the same frequency, the greater the intensity of vibration was, the greater TTS of vibratory sensation was (Fig. 1).
2. On the unexposed side, some TTS of 125Hz and 250Hz vibratory sensation were statisticaly significant (Fig. 2).
3. The changes of skin temperature owing to vibration exposure showed similar pattern on the exposed side and the unexposed side. So fine were the changes that they were not significant immediately after vibration exposure but significant 6min. after, by the analysis of variance on the both sides (Fig. 1-4, 2-4, 3-4, 4-4). And it was considered that the effect of the skin temperature on the vibratory sensation threshold was negligible, because the average values of skin temperature ranged from 30°C to 35°C.
4. The prediction equations for TTS of vibratory sensation are shown in (Table 2, Fig. 5). The values of TTS of vibratory sensation measured in Part 1 were in reasonably good agreement with the predicted values by these equations (Fig. 6). Therefore, it was considered that these prediction equations have similarity under the condition of this experiment.
5. Equal TTS curves were compared with exposure boundary of ISO (1973) (Fig. 5-2, Fig. 7).
As the result, both characteristic curves were similar to each other at the frequencies from 63Hz to 500Hz, while different at the higher and lower frequencies. About this difference, it was discussed that Pacinian corpuscle, which is conceibable to be the receptor of vibratory sensation threshold measured in this experiment, has less sensitivity in these lower frequencies and that there would be room for further study in exposure boundary of ISO in that higher frequencies.
And it was considered that 30min. level of exposure boundary of ISO was equivalent to TTS of 12.5-15dB on the 63Hz vibratory sensation, 17.5-22.5dB on the 125Hz and 22.5-27.5dB on the 250Hz. Eight-hour level of exposure boundary of ISO was equivalent to TTS of 5dB, 7.5dB and 10-12.5dB, respectively.

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The effect of carbon monoxide (CO) on the tissue respiration was studied in the renal cortex of the rabbit using the fluorometric method which has been developed for the determination of reduction of intracellular pyridine nucleotide component.
Blood Po₂ of the renal artery and vein was measured with a gas analyzer, and the renal blood flow was examined with a electromagnetic flowmeter.
The redox state of the renal cortical surface was altered by the CO inhalation of 0.5%, 1%, 2% and 3%, or the exposure to hypoxic hypoxia.
Even when considering the Haldane effect, CO hypoxia caused a increase in fluorescence response at milder hypoxidosis that caused by the exposure to hypoxia, and developed the characteristic slope of the fluorescence increment which was not observed during the exposure to hypoxia.
Varying the CO and oxygen concentrations in the inhaled gas, it was demonstrated that there were dose-response relationships between the redox state of the renal tissue and the CO concentration or the oxygen concentration in the inspired gas.
The prolonged exposure to CO resulted in a slow decrease in the renal blood flow, while the exposure to hypoxia showed a more rapid and marked decrease in blood flow.
Some implications of hystotoxic properties of CO were discussed from toxicological points of view on the results obtained, and it was suggested that CO had the direct effect on the respiratory chain when the blood contained COHb over approximately 18.3%, and the histotoxic property appeared to play an important role in the CO toxicity at COHb levels over 31.2%.

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