The purpose of this investigation as the basic research for the studies on soil aeration is to calculate the gaseous diffusion coefficient of soils from the air permeability which is easily measured. The results obtained are as follows:
1) Scattered relations are observed between diffusion coefficient and air permeability of soils which are variously remoulded. But there is a tendency mentioned in 3) in above relation.
2) The permeabilities depend on the size of soil particles, but the diffusion coefficients are not affected by them.
3) The following formula holds for the relation between diffusion coefficient D and air permeability K when measured under the conditions of various water content in a given remoulded soil consisting of closely graded particles.
D=aKⁿ where n≅1
4) If the relation between diffusion coefficient D and air permeability K under a given water content in a soil is known, by using the above formula, diffusion coefficients D of any water content in same soil are calculated from air permeability easily measured.

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The present investigation was performed in a coldenvironment to determine the main substances used for heat production and for gluconeogenesis in sheep which have peculiar nutritional requirement as compared with a monogastric animal.
Four clipped sheep were exposed to ambient temperature of 0°Cfor 7 days in the climatic chamber, and their physiological responses, blood and urine constituents were measured during the exposure period.
Immediately after the start of the exposure, severe shivering arose from the limbs, extending over the body, and heart rate and heat production were both increased remarkably. These high levels were maintained for 7 days. Water intake and urine volume decreased distinctly but respiration rate only tended to decreased. Body temperature did not exhibit clear change but the diurnal fluctuations were smaller than those at 20°C.
The plasma free fatty acid concentration increased rapidly. Blood glucose and blood P_co2 increased a little but not significantly on and after the 4th day of exposure. Blood free amino acids, lactic acid and volatile fatty acids concentrations did not show any clear changes. The daily urinary excretion of ketone bodies decreased slightly but that of nitrogen hardly changed.
The present experiment confirmed that the changes observed in the sheep under the cold environment were almost the same as those of reported in human, dog and other monogastric animals.

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The glucose metabolism of sheep under the constant environmental temperatures of 20°C and 0°C was measured by isotope dilution method with the single injection and the constant infusion of ¹⁴C- and ³Hlabelled glucose.
In the environmental temperature of 20°C, the pool size, turnover rate, re-cycling rate of glucose and the percentage of CO₂ derived from glucose to the total expired CO₂ were 159.5 mg/kg, 2.63 mg/min/kg, 0.40 mg/min/kg and 5.37%, respectively.
On the 4th day after the exposure to 0°C, the values of pool size, turnover rate, re-cycling rate and CO₂ percentage derived from glucose were increased to 1.67 (226.0 mg/kg), 1.86 (4.88 mg/min/kg), 2.93 (1.17 mg/ min/kg) and 2.23 (12.0%) times high compared with those of 20°C.
These results indicated that the sheep which scarecely absorbs glucose from the alimentary tracts synthesize glucose by gluconeogenesis and utilize it with the same rate as the monogastric animal. Under the cold environment, the turnover rate of glucose increased remarkably to be used to quite a large extent as the sources for the heat production.

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1) The experiment was made in early autumn (September) on the effects of fruiting and different soil moisture condition on the dry matter yield in Satsuma mandarin trees.
2) The dry weight and total carbohydrate content of 3-year-old stems and feeder roots was higher when the trees were def ruited in early autumn than those of the untreated fruiting trees. Furthermore, in some fruiting trees treated with the plot of ringing on their trunk, higher dry weight and total carbohydrate content in their peel and pulp was observed.
3) The dry weight of various organs did not show significant differences between the trees grown in low moisture condition (pF 3.0-3.5) and those grown in medium moisture condition (pF 2.0-2.5) during the 30 days period of investigation.
4) When the trees grown in the low moisture conn dition during 30 days period in early autumn were transferred to the medium moisture condition, two months later, the rate of dry matter of new-leaves, old-leaves and fruits of the plants became higher than those of the trees placed in the medium moisture condition throughout the period.
5) The dry weight of fruits and total sugar and total carbohydrate content of fruits did not show significant differences although the plants were treated in two main different soil moisture conditions, but the rate of dry matter of fruits became higher in reduced soil moisture content. Therefore, the fruits of high quality on the trees grown in the low moisture condition appeared to result from reduced absorption of water by the fruits. In the pulp of the trees placed in the low moisture condition, higher fructose and glucose contents and lower sucrose contents were observed.
6) The translocation of photosynthates into the fruits appeared to be unaffected by the low moisture condition during the 30 days period of investigation in early autumn.

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The growth cabinet is widely in use today as a research tool for studying the growth and physiological processes of plants under controlled environment. The new design incorporates an adaptive control system in regard to environmental control using a low cost computer. An experimentation with a prototype production model has yielded the following positive result after performance test with or without plant materials, namely, enhanced control accuracy through the use of adaptive control method with computer; temperature to within±0.2°C and relative humidity to within ±1%.

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