• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.317-343
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• 1977

This study was carried out to obtain the informations about evaporation from pot, soil temperature and soil atmosphere composition in pot, and the effect on the growth of nine ornamental species using seven different containers. The investigated containers were clay pot(CP), clay pot painted in green(CP-P), varnished clay pot(CP-V), polyethylene film inserting in clay pot(CP-PI), clay pot mulched with black polyethylene film(CP-PM), porcelain pot(POP), and plastic pot(PLP). Nine ornamental species were balsam(Impatiens balsamina), chrysanthemum(Chrysanthemum morifolium), cosmos(Cosmos bipinatus), English ivy(Hedera helix), geranium(Pelargonium zonale), kochia(Kochia scoparia var. trichophila), marigold(Tagetes patula), ornamental kale(Brassica oleraceae var. acephala), and salvia (Salvia splendens). The results obtained are summarized as follows: 1. Dry weight of all tested species grown in PLP, POP, CP-P, CP-V and CP-PI was heavier than that of CP. 2. Plant height in nine tested species grown in PLP, POP, CP-P, CP-V, and CP-PI was taller than that of CP. 3. Geranium grown in PLP, POP, CP-P, and CP-V gave more number of leaf than that of CP. 4. The number of flower in balsam grown in PLP, POP, CP-P, CP-V and CP-PI was more than that of CP. The result from marigold was very similar to this tendency. Spike length and floret number in salvia gave the same tendency, but its spike number was not different among containers used. 5. The average diurnal evaporation from PLP and POP was about 43% of that of CP. About two third of total evaporation from CP was through pot wall. 6. The evaporation rate from the slowest to the highest was PLP, POP, CP-P, CP-V, CP-PI, CP-PM and CP. Containers inhibiting evaporation through pot wall hold more soil moisture than CP from one day after water supply. 7. The more evaporative water-loss from containers gave the lower soil temperature. The variation of soil temperature among containers was higher during the day than the night. 8. The $O_2$ concentration of soil atmosphere in CP was higher than that of nonporous containers, and the difference between them was 0.40-1.12%. The range of the $O_2$ concentration 17.95~19.62%. The $CO_2$ concentration of soil atmosphere in CP was lower than that of nonporous containers, and its range was 0.59-1.76%. This deviation in soil atmosphere composition did not influenced on the growth of plants. 9. There was a possitive correlation between the amount of soil water and the plant growth. 10. Plant grown on CP gave more total nitrogen content in top growth than that on PLP. C/N ratio was somewhat low in plant on CP. From the above results, $O_2$ and $CO_2$ concentration in soil atmosphere did not gave enough deviation to the extent which affect the plant growth. The effect of soil moisture on the plant growth using different containers was the far-most significant factor from this investigation. Therefore, it was obious that the utilization of the nonporous container might save the cost for water supply and reduce the production cost of the pot-grown ornamental plant in Korea eventually.

• Sleep Medicine and Psychophysiology
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• v.24 no.2
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• pp.106-117
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• 2017

Objectives: Obstructive sleep apnea (OSA) is a sleep-related breathing disorder that is characterized by repetitive collapse or partial collapse of the upper airway during sleep in spite of ongoing effort to breathe. It is believed that OSA is usually worsened in REM sleep, because muscle tone is suppressed during REM sleep. However, many cases showed a higher apnea-hypopnea index (AHI) during NREM sleep than during REM sleep. We aimed here to determine the characteristics of REM sleep-dependent OSA (REM-OSA) and NREM sleep-dependent OSA (NREM-OSA). Methods: Five hundred sixty polysomnographically confirmed adult OSA subjects were studied retrospectively. All patients were classified into 3 groups based on the ratio between REM-AHI and NREM-AHI. REM-OSA was defined as REM-AHI/NREM-AHI > 2, NREM-OSA as NREM-AHI/REM-AHI > 2, and the rest as sleep stage-independent OSA (IND-OSA). In addition to polysomnography, questionnaires related to subjective sleep quality, daytime sleepiness, and emotion were completed. Chi-square test, ANOVA, and ANCOVA were performed. Results: There was no age difference among subgroups. The REM-OSA group was comprised of large proportions of mild OSA and female OSA patients. These patients experienced poor sleep and more negative emotions than other two groups. The AHI and oxygen desaturation index (ODI) were lowest in REM-OSA. Sleep efficiency and N3 percentage of REM-OSA were higher than in NREM-OSA. The percentage of patients who slept in a supine position was higher in REM-OSA than other subgroups. IND-OSA showed higher BMI and larger neck circumference and abdominal circumference than REM-OSA. The patients with IND-OSA experienced more sleepiness than the other groups. AHI and ODI were highest in IND-OSA. NREM-OSA presented the shortest total sleep time and the lowest sleep efficiency. NREM-OSA showed shorter sleep latency and REM latency and higher percentage of N1 than those of REM-OSA and the highest proportion of those who slept in a lateral position than other subgroups. NREM-OSA revealed the highest composite score on the Horne and ${\ddot{O}}stberg$ questionnaire. With increased AHI severity, the numbers of apnea and hypopnea events during REM sleep decreased, and the numbers of apnea and hypopnea events during NREM sleep increased. The results of ANCOVA after controlling age, sex, BMI, NC, AC, and AHI showed the lowest sleep efficiency, the highest AHI in the supine position, and the highest percentage of waking after sleep onset in NREM-OSA. Conclusion: REM-OSA was associated with the mild form of OSA, female sex, and negative emotions. IND-OSA was associated with the severe form of OSA. NREM-OSA was most closely related to position and showed the lowest sleep efficiency. Sleep stage-dependent characteristics could provide better understanding of OSA.