• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.2
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• pp.74-87
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• 2016

Potato phenology, growth, and yield are projected to be highly affected by global warming in the future. The objective of this study was to examine the responses of potato growth and yield to environmental elements like temperature, solar radiation, and daylength. Planting date experiments under open field condition were conducted using three cultivars differing in maturity group (Irish Cobbler and Superior as early; Atlantic as mid-late maturing) at eight different planting dates. In addition, elevated temperature experiment was conducted in four plastic houses controlled to target temperatures of ambient temperature (AT), $AT+1.5^{\circ}C$, $AT+3^{\circ}C$, and $AT+5^{\circ}C$ using cv. Superior. Tuber initiation onset was found to be hastened curve-linearly with increasing temperature, showing optimum temperature around $22-24^{\circ}C$, while delayed by longer photoperiod and lower solar radiation in Superior and Atlantic. In the planting date experiments where the average temperature is near optimal and solar radiation, rainfall, pest, and disease are not limiting factor for tuber yield, the most important determinant was growth duration, which is limited by the beginning of rainy season in summer and frost in the late fall. Yield tended to increase along with delayed tuber initiation. Within the optimum temperature range ($17^{\circ}-22^{\circ}C$), larger diurnal range of temperature increased the tuber yield. In an elevated temperature treatment of $AT+5.0^{\circ}C$, plants failed to form tubers as affected by high temperature, low irradiance, and long daylength. Tuber number at early growth stage was reduced by higher temperature, resulting in the decrease of assimilates allocated to tuber and the reduction of average tuber weight. Stem growth was enhanced by elevated temperature at the expense of tuber growth. Consequently, tuber yield decreased with elevated temperature above ambient and drop to almost nil at $AT+5.0^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.214-223
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• 2017

A total of 15 different corn hybrids, Kwangpyeongok, Gangdaok, Yanganok, Singwangok, Jangdaok, Cheonganok, Cheongdaok, Andaok, Dapyeongok, Pyeongkangok, Pyeonganok, Daanok, Sunwon 184, Gangilok, and P3394 was used to investigate the growth and yield depending on the sowing date. The sowing dates were April 5, June 25, and July 5 and each experiments was performed in triplicste. The growth of Gangdaok was the highest. However, although the growth of Kwangpyeongok, was lower thanthar of Gangdaok, its stem height to ear height ratio was lower than that of Gangdaok, thus, Kwangpyeongok may be more suitable for stable cultivation. Both growth and yield of Daanok were low, regardless of planting date, but yield and ear shape of Pyeongkangok and Dapyeongok were for fresh corn. Growth and yield of the 15 different corn hybrids varied depending on the planting date, However, the growth degree days (GDD) was the most important factor governing the maturity of corn. More than $1500^{\circ}C$ of GDD was sufficient to harvest mature corn hybrids in the central region of Korea. Besides yield and growth, other characteristics, such as sweetness and taste of the hybrids, should be investigated further the selection of the best corn hybrid.

• Korean Journal of Plant Resources
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• v.26 no.4
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• pp.441-449
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• 2013

This study was conducted to select some useful plants as functional material candidates. A total of 38 plants were preliminarily screened for the anti-inflammatory and antioxidant activities. The preliminarily selected 8 plants were further investigated to verify the in vitro inhibitory effect on inflammation and oxidative stress. Boehmeria platanifolia (root), Carpinus coreana (branch), and Eupatorium japonicum (leaf) inhibited the expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-treated RAW 264.7 cells. Eupatorium japonicum (leaf) suppressed the expression of cyclooxygenase-2 (COX-2), whereas Boehmeria platanifolia (root) and Prunus yedoensis (branch) inhibited the transcription of nuclear factor-kappa B (NF-${\kappa}B$). Treatment with the extracts ($2.5{\sim}20{\mu}g/ml$) of Abutilon theophrasti (leaf, flower/seed) and Hemistepta lyrata (stem) did not show toxicity on RAW 264.7 cell proliferation, but treatment with $2.5{\mu}g/ml$ of Boehmeria platanifolia (root) exhibited cell toxicity. Carpinus coreana (branch) and Prunus yedoensis (branch) showed potent scavenging activities on peroxynitrite. Akebia quinata (flower), Carpinus coreana (branch), and Prunus yedoensis (branch) effectively inhibited reactive oxygen species (ROS). Abutilon theophrasti (leaf), Boehmeria platanifolia (root), Carpinus coreana (branch), and Eupatorium japonicum (leaf) exhibited strong inhibitory capacity with regard to nitric oxide (NO) production. The results suggested that Abutilon theophrasti (leaf) has in vitro anti-inflammatory and antioxidant activities, and that is a useful functional material candidate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.605-612
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• 2005

In previous studies, we evaluated the effect of the 6 energy-tonic or blood-building prescriptions of traditional oriental medicine, and observed that Si-Wu-Tang and Bu-Zhong-Yi-Qi-Tang showed high activity in the protection of the gastrointestinal and hematopoietic organs in irradiated mice. But any of these prescriptions did not show a high activity in the activation of the immune cells. We performed this study to design an herb mixture which protects the self-renewal tissues and also promotes recovery of the immune system against radiation damage. In order to meet all the requirements, we designed a new mixture of 3 edible herbs listed in Korean Food Code. The mixture of Angelim gigas radix, Cnidium officinale rhizoma and Paeonia japonica radix was decocted with hot water, and the activities of the water extract (HIM-I) were evaluated. HIM-1 stimulated the immune cells in a much higher extent than the traditional prescriptions, and promoted dramatically the growth of bone marrow stem cells in vitro. Also, HIM-1 protected digestive and hematopoietic organs against radiation as effectively as the 2 prescriptions, Si-Wu-Tang and Bu-Zhong-Yi-Qi-Tang. On the other hand, it showed high in vitro antioxidative activity that might be considered as a mechanism of the protective effects against radiation. Although the detailed mechanisms of those effects remain to be elucidated, these results indicated that HIM-I might be a useful agent for protection and recovery of body from various risk factor as well as radiation, especially since it is a relatively nontoxic natural product.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.1
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• pp.65-72
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• 2009

Skin aging appears to be principally attributed to a decrease in both levels of Type I collagen and regeneration ability of dermal fibroblasts. It is important to introduce an efficient and safe agent for effective management of skin aging. To this end, we performed screening for anti-ageing agents and then found that vegetable peptones (pea and wheat) promoted cell proliferation of adult stem cells. Vegetable peptones may be considered as useful medium additives because it can supply nutrients, peptides, amino acids or growth factor analogues. This study was designed to investigate effects of vegetable peptones on cell proliferation/collagen production and their possible mechanisms in human dermal fibroblasts. In cell proliferation assay, vegetable peptones significantly promoted cell proliferation in a concentration-dependent manner. In addition, human COL1A2 promoter luciferase and type I procollagen synthesis assays showed that vegetable peptones induce type I procollagen production through the activation of COLlA2 promoter. In both TGF-${\beta}1$ luciferase reporter and ELISA assays, vegetable peptones was found to induce TGF-${\beta}1$ production, suggesting that vegetable peptones induce type I procollagen production through the activation of TGF-${\beta}1$. When applied topically in a human skin twice a day for an 4-week period of time, vegetable peptones did not induce any adverse reactions. Theretore, based on these results, we suggest the possibility that vegetable peptones may be considered as an attractive, wrinkle-reducing candidate for topical application.

• Korean Journal of Social Welfare
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• v.50
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• pp.33-59
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• 2002

This study aims to provide policy suggestions by examining the perception and attitude of Koreans toward the welfare rights. The study was done through a telephone survey conducted by an opinion research institute on 2,050 respondents in 16 cities and provinces. The results are as follows. First, a majority of Koreans responded that the primary responsibility for welfare rests with the government and perceived their welfare receipt rights in a positive way. Respondents also showed an assertive attitude toward exercising their rights by stating that they intend to file a demurrer or participate in civic activities. Second, in terms of duty performance, most respondents showed different positions concerning tax hike and insurance rate increase, although they showed a stronger opposition to an increase in insurance fee. In addition, 90% of the respondents were in favor of building welfare institutions in the residential area and an overwhelming proportion of the respondents indicated that they would take an active part in welfare development by regularly paying taxes and volunteering. Third, the respondents gave a very negative rating to Koreas welfare system and its overall level. That is, people thought that the level of Koreas welfare system is on a par with that in developing or underdeveloped countries, and that the welfare system benefits no one or only the rich. People generally felt that there was not one proper welfare institution. In conclusion, the study found that Koreans have keen awareness of their welfare rights and proactive attitude toward welfare development, whereas negative viewpoint toward tax and insurance fee increases. This may stem from peoples distrust of government welfare policies and the existing welfare system. This study suggests that welfare policy is an important factor in determining peoples political attitude. Therefore, government authorities must recognize people not as passive receivers of welfare benefit but as active policy partners, and establish policies that reflect peoples high welfare rights perception and willingness to take part in welfare development.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.359-365
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• 1985

The four rice varieties, Kwanak, Nongbaek, Pungsan and Nampung-byo were cultivated to examine the growth conditions and grain yield in a Gyuam SiL paddy field irrigated with cold water around $17^{\circ}C$. Water temperatures for various distances from the inlet were measured. The results were summerized as follows. 1. Culm length, panicle exertion, diameter of the 3rd internode stem, heading date, fertilization rate, ripeness rate, no. of grains per panicle and grain yield were sensitive to water temperature. Panicle length, flag-leaf length, diameter of spike-neck and no. of panicles, however, were negligibly sensitive and there were no differences among varieties. 2. Elongations of the 2nd and 3rd internode steam were unsensitive to water temperature. 1st internode elongation and 4th internode development, however, were sensitive which was major factor in the culm length. 3. Ratios of partial dry weight to total dry weight were closely correlated with water temperature, Therefore, dry weight of grain was increased with water temperature while that of plant and root decreased. 4. Chlorophyll contents were decreased with the increment of water temperature and the highest at $20^{\circ}C$. 5. There was no grain yield at $17^{\circ}C$, Increases of grain yield to water temperature per unit were order at Pungsan > Kwanak > Nongbaek > Nampung. 6. The critical temperature in grain yield was $21^{\circ}C$. Optimum temperatures of Japonica ${\times}$ Indica types were higher than those of Japonica types.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.210-220
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• 2019

Population growth and the increase of energy consumption due to civilization caused global warming. Temperature on the Earth rose about $0.7^{\circ}C$ for the last 100 years, the rate is accelerated since 2000. Temperature is a factor, which determines physiological action, growth and development, survival, etc. of the plant together with light intensity and precipitation. Therefore, it is expected that global warming would affect broadly geographic distribution of the plant as well as structure and function ecosystem. In order to understand the effect of global warming on the ecosystem, a study about the effect of temperature rise on germination and growth in the plant is required necessarily. This study was carried out to investigate the effects of experimental warming on the germination and growth of two oak species(Quercus mongolica and Q. serrata) in temperature gradient chamber(TGC). This study was conducted in control, medium warming treatment($+1.7^{\circ}C$; Tm), and high warming treatment ($+3.2^{\circ}C$; Th) conditions. The final germination percentage, mean germination time and germination rate of two oak species increased by the warming treatment, and the increase in Q. serrata was higher than that in Q. mongolica. Root collar diameter, seedling height, leaf dry weight, stem dry weight, root dry weight, and total biomass were the highest in Tm treatment. Butthey were not significantly different in the Th treatment. In the Th treatment, Q. serrata had significantly higher H/D ratio, S/R ratio, and low root mass ratio (RMR) compared with control plot. Q. mongolica had lower RMR and higher S/R ratio in the Tm and Th treatments compared with control plot. Therefore, growth of Q. mongolica are expected to be more vulnerable to warming than that of Q. serrata. The main findings of this study, species-specific responses to experimental warming, could be applied to predict ecosystem changes from global warming. From the result of this study, we could deduce that temperature rise would increase germination of Q. serrata and Q. mongolica and consequently contribute to increase establishment rate in the early growth stage of the plants. But we have to consider diverse variables to understand properly the effects that global warming influences germination in natural condition. Treatment of global warming in the medium level increased the growth and the biomass of both Q. serrata and Q. mongolica. But the result of treatment in the high level showed different aspects. In particular, Q. mongolica, which grows in cooler zones of higher elevation on mountains or northward in latitude, responded more sensitively. Synthesized the results mentioned above, continuous global warming would function in stable establishment of both plants unfavorably. Compared the responses of both sample plants on temperature rise, Q. serrata increased germination rate more than Q. mongolica and Q. mongolica responded more sensitively than Q. serrata in biomass allocation with the increase of temperature. It was estimated that these results would due to a difference of microclimate originated from the spatial distribution of both plants.

• Korean Journal of Environmental Biology
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• v.39 no.3
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• pp.354-361
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• 2021

Understanding the phytotoxic mechanism of methyl bromide (MB), an essential fumigant during the quarantine and pre-shipment process, is urgently needed to ensure its proper use and reduce international economic losses. In a previous study, two main MB-induced toxic mechanisms such as reactive oxygen species (ROS) and auxin distribution were selected by analyzing transcriptomic analysis. In the study, a 3-week-old A. thaliana was supplied with 1 mM ROS scavengers [N-acetyl-L-cysteine (NAC) or L-glutathione (GSH)] and 1µM indole-3-acetic acid(IAA) three times every 12 h, and visual and gene expression assessments were performed to evaluate the reduction in phytotoxicity by supplements. Phytotoxic effects on the MB-4h exposed group were decreased with GSH application compared to the other single supplements and a combination of supplements at 7 days post fumigation. Among these supplements, GSH at a concentration of 1, 2, and 5mM was suppled to A. thaliana with MB-fumigation. During a long-term observation of 2 weeks after the fumigation, 5 mM GSH application was the most effective in minimizing MB-induced phytotoxic effects with up-regulation of HSP70 expression and increase in main stem length. These results indicated that ROS was a main key factor of MB-induced phytotoxicity and that GSH can be used as a supplement to reduce the phytotoxicity of MB.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.14-21
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• 2022

Uniform scions and rootstocks should be produced to ensure grafting success. Light quality is an important environmental factor that regulates seedling growth. The effects of warm- and cool-white light emitting diode (LED) ratios on seedling growth were investigated. Scions and rootstocks of cucumber, tomato, and watermelon were grown in a closed transplant production system using LED as the sole lighting source. The LED treatments were W1C0 (only warm-white), W1C1 (warm-white: cool-white = 1:1), W3C1 (warm-white: cool-white = 3:1), and W5C2 (warm-white: cool-white = 5:2). The seedlings grown in W1C1 had the shortest hypocotyls, and the seedlings grown in W1C0 had the longest hypocotyls among the three tested vegetables. The hypocotyls of watermelon scions, watermelon rootstocks, and tomato rootstocks were shortest in W1C1, followed by those in W3C1, W5C2, and W1C0, but there was no significant difference between W3C1 and W5C2, which remained the same as the ratio of cool-white LEDs increased. In addition, tomato scions had the first and second longest hypocotyls in W1C0 and W3C1, respectively, and the shortest hypocotyls in W5C2 and W1C1, along with W5C2 and W1C1, although the difference was not significant. The stem diameter was highest in W1C0 except for tomato seedlings and rootstocks of watermelon. The shoot fresh weight of scions and rootstocks of cucumber and watermelon and the root fresh weight of cucumber scions were lowest in W1C1. These results indicated that different ratios of LED lighting sources had a strong effect on the hypocotyl elongation of seedlings.