Third year high school students of Numatate (Akita Prefecture) and Tanegasima (Kagosima Prefecture) were examined by direct inspection and by study of casts and two-dimensional roentgenographic cephalograms as a part of an epidemilogical survey. Samples consisted of 401 subjects ranging from 17 years 3 months to 18 years 11 months old. There were no significant differences in incidence of third molar agenesis between left and right side. Also, no significant differences were found in incidence of each type of third molar agenesis between local samples and between sexes. No significant difference in the incidence of individuals with fully erupted, partly erupted and impacted third molar was seen between local samples and between sexes. The third molars in 71.9% of the subjects without agenesis were impacted. One or more third molars were missing in 43.1% of subjects. This is higher than any of the rate for other populations so far reported.

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For comparing the pattern of interrelationship of seven anthropometric measurements and eight body build indices in the different phase of growth, principal component analysis was applied to each of ten cohorts of three-year age range consisting of 7-18 years old school children of Nase City. The loading patterns of component I indicating body size started to change at the time corresponding to adolescent growth spurt. Rohrer index, Livi index, ponderal index and relative weight were highly significantly correlated in most cohorts with component II representing body build, and are considered to be appropriate as body build indices. Those indices, however, are much less suitable in a quantitative sense for body build indices in girls at puberty who correspond to junior high school girls. W/H and Quetelet index were involved bilaterally with body size and body build and are not specified either of them. The skinfold thickness was closely associated with component III which is orthogonal to componentII must be taken into consideration in evaluating body fatness of children.

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Eight male and six female students, wearing only shorts in male or Bikini swimming suits in female, were exposed to 20, 22, 24, 26 and 28°C in a climatic chamber for 60min in sitting posture on separate days. Air velocity was less than 20cm/sec and relative humidity was 50%. Metabolic rate, rectal temperature, mean skin temperature, heart rate and sweat rate were measured. Measurements between the 55th and 60th min of exposure were used for statistical analyses.
The analysis of variance comfirmed a significant effect of air temperature on metabolic rate. Metabolic rates at 24 and 26°C were significantly lower than that at 20, 22 and 28°C. The regression analysis disclosed that the relationships between metabolic rate and air temperature or mean skin temperature were curved. According to these parabolic regression equations of metabolic rate on air temperature or mean skin temperature, the minimal value of metabolic rate will be obtained when air temperature would become about 25°C or mean skin temperature would become about 32°C.

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The purposes of this study were to show changes with aging in steadiness and stability of standing posture, and to show the relationships between the steadiness and stability on one hand and the isometric strength of ankle dorsal flexion (ADF), ankle planter flexion (APF), or hallucial flexion (HF) on the other.
The steadiness was evaluated by the length (L) of trace of the center of foot pressure (CEP) while maintaining the following postures for 20 seconds: (1) quiet standing posture (QSP), (2) backward leaning posture (BLP) with CFP at 25% from the heel regarding the foot length as 100%, and (3) forward leaning posture (FLP) with CFP at 65%. The stability was evaluated in terms of the CFP in extreme backward and forward leaning postures maintained for 10 seconds. These measurements were obtained while the subjects were standing on a Gravicorder (Anima K. K. ) with the eyes opened and the stance closed. The isometric strength was measured by a strain gage dynamometer in sitting position with the knee extended. The angle of the ankle was fixed at 90 degrees in APF and HF, and at 105 degrees in ADF. The age of subjects, 99 males and 140 females, ranged from 20 to 79 years. The results obtained were as follows:
(1) The steadiness reduced in both sexes with increase of age after fifties in QSP and FLP, and after twenties in BLP.
(2) The forward limits (FL) of the stability area shifted backward with age after fifties in both sexes, while the backward limits (BL) of the stability area shifted forward after twenties in both sexes.
(3) The isometric strength of APF and HF decreased with age after forties in both sexes, while that of ADF decreased with age after twenties in female and after thirties in male. These changes in the muscle strength corresponded with the changes in the steadiness and stability described above.
(4) No significant correlations (partial correlation holding the age constant) were shown between the L value in QSP and the isometric strength of APF, ADF and HF. Significant correlations (partial correlation holding the age constant) were shown between the L value in FLP and the APF strength, the BL and the ADF strength, and the FL and the APF as well as the HF strength, respectively.

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Experiments were conducted on four healthy male and four healthy female subjects in an artificial climate room at an air temperature of 241°C and a relative humidity of 60%. Skin temperature of the right index finger, the arm, the forehead and the foot, as well as pain sensation, blood pressure, pulse wave etc. were measured before, during and after simultaneous immersion of both feet for 10min in water at 10°C.
Following immersion of the feet, finger temperature declined in all subjects reaching a minimum value at 3min after which there was a rise of temperature. The amplitude of the pulse wave showed the same two phase change in all subjects reaching a minimum value at 1min. These results are similar to those from the Inuit (the Eskimo) reported by PAGE et al. (1953) and LIVINGSTONE et al. (1978).
In all subjects, systolic and diastolic blood pressure increased on feet immersion. Both diastolic and systolic responses tended to be greater in male than in female subjects. Men experienced less pain than women following feet immersion.

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In summer, 15 male students wearing only shorts were exposed to 15°C for 90 minutes in supine posture (exposure period), and then they were covered with blankets for 60 minutes (recovery period). Heart rate, blood pressure, heat production, rectal temperature and skin temperatures at 9 sites were recorded on subjects before, during and after exposure to a cold environment.
Heart rate decreased significantly under the cold exposure, and in the recovery period, it decreased further significantly. In the recovery period, subjects with the lowest mean skin temperature tended to decrease their heart rate most. Skin temperature at finger was maintained at a higher level due to active vasomotor tone than that at toe during cold exposure, and increase rate of temperature at finger (7.9°C/hr) was larger than that at toe (1. 6°C/hr) in the recovery period. Rectal temperature fell by 0. 38°C by the end of the exposure. For 60 minutes in the recovery period, while the skin temperatures rose quickly, rectal temperature fell steeply to 0.34°C below the end of exposure value. In the recovery period, subjects with the lowest forehead skin temperature tended to fall their rectal temperature most, there was no significant relationships between fall in rectal temperature and change in skin temperatures of other sites.

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By application of principal component analysis using four somatometric parameters-head length, head breadth, bizygomatic breadth and morphological facial height-14 ethnic groups in Taiwan (544 males and: 546 females) consisting of 10 aborigine tribes-the Atayal, Saisiyat, Bunun, Tsou, Rukai, Paiwan, Puyuma, Ami, Yami, and Thao-two Pepo tribes or sinicized peoples-the Taivoan and Pazeh-and two stocks of Chinese-the Hoklo and Hakka-which are distinguishable from one another by cultural, social and historical differences (Table 1), were clearly classified into the five following groups:
Group 1: Yami, Atayal
Group 2: Saisiyat
Group 3: Paiwan, Rukai, (Hoklo)
Group 4: Bunun, Tsou
Group 5: Ami, Thao, Puyuma, Taivoan, Pazeh, Hakka
This classification for the peoples of Taiwan was made by comparing the patterns of scatter diagrams drawn by the scores of the first and second principal component for the individuals with regard to their respective ethnic group and sex, as shown in Figs. 1-5.
The first (Z_l) and second (Z₂) principal components are given as the solutions to the following quadranomial equations (Table 4):
Z₁=0.366x₁'+0.566x₂'+0.630x₃'+0.400x₄'
Z₂=0.617x₁'-0.494x₂'-0.271x₃'+0.549x₄' for males,
Z₁=0.318x₁'+0.554x₂'+0.615x₃'+0.462x₄'
Z₂=0.770x₁'-0.479x₂'-0.231x₃'+0.352x₄' for females.
The symbols x₁, x₂, x₃, x₄, and x₁'-x₄' indicate the head length, head breadth, bizygomatic breadth, morphological facial height and the normalized values for the variables, respectively. The four coefficients of these equations have similar sizes and the same signs between Z_l and Z₂ in both sexes, Thus, both males and females have similar patterns in their scatter diagrams in each of the 14 ethnic groups, as shown in the figures.
The new summarized variables-Z₁ (horizontal axis) and Z₂ (vertical axis) are recognized as the factors showing the size and the shape of the sample, respectively, and the cumulative contribution rate is 74.6% in males and 75.2% in females up to the second principal component.
The pattern of the Hoklo is similar to those of the Paiwan and Rukai in Group 3. It seems, however, that this is a result of the small number of parameters used in the principal component analysis and that, therefore, some additional parameters, such as the stature, nose height and breadth, Mongolian fold, etc., should be used.
The classification presented above contains too many groups for the aborigine minority in Taiwan with a population of only two lakh or so, and it is believed that such "polymorphism" seen in these groups is due to the racial mixture between the aborigines (protoMalays), the former occupants of Taiwan, and the Chinese, i, e., the Hoklo and Hakka, who migrated later from the south of the Chinese mainland to Formosa.
The Ami, Thao and Puyuma in Group 5 of the above classification show morphological similarities in their physical traits to the Peipo tribes and the Hakka. Furthermore, the Saisiyat (Group 2) also have morphological affinities to Group 5 in their half population. The non-sinicized morphological traits of the Taiwan aborigines, the proto-Malays distributing over the most northerly area of south Asia, are seen clearly in those of the Yami and Atayal (Group 1) and the Paiwan and Rukai (Group 3).

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