• 생물환경조절학회지
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• 제12권2호
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• pp.101-105
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• 2003

양파 plug묘 육묘시 일장조절에 의한 우량묘 생산을 위해 자연일장을 대비로 하여 11.5시간, 12.5시간 및 13.5시간의 일장 하에서 월륜과 창녕대고 품종을 200공 plug tray에 육묘한 후에 직경 16cm pot에 이식하여 16시간의 일장 하에서 재배하였다. 엽수, 엽초경, 초장 및 엽초장은 시기가 경과할수록 증가하였으나 13.5시간 일장에서의 초장과 엽초경은 일장처리 20일 후에는 감소하였다. 일장에 따른 생육은 엽수 및 엽초경은 장일조건에서 생육이 좋았으나 초장 및 엽초장은 장일에서 억제되는 경향을 나타내었다. 장일조건에서 육묘한 것일수록 이식 후에 구가 크고 비대도 빨랐다. 이상의 결과로 볼 때 육묘기간 중의 장일처리로서 도장의 억제 및 우량묘 생산의 가능성을 보여주고 있다.

• 한국작물학회지
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• 제42권4호
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• pp.466-472
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• 1997

Vegetable perilla, "Ipdlkkae 1"(Perilla frutescens var japonica Hara), was tested about the flowering and maturing responce in summer and winter. In summer season, it was researched about those responses according to the change of seeding date from May 15th to Oct. 15th at one month interval in the field. "Ipdlkkae 1" flowered Oct. 2nd under the day length of eleven hours and fourty-one minutes, compared with Sep. 6th (day length of twelve hours and fourty-three minutes) of "Yepsildlggae". And those responses showed that vegetable perilla was have to seeded before July 15th for two reason. The first is a unique response of perilla to day length. If perilla stay under short-day condition for some days, perilla will flower after four weeks. The second is a weather, especially frost and cold. In the test of latest seeding at Oct. 15th, the plants flowered more late than normal flowering period and they were not able to mature for frost of early winter. And this result showed that any other species, which has the characteristic of later flowering than that of "Ipdlkkae 1", could not able to mature in the field. In winter time, this species was tested about the same responses according to the change of short-day treatments. In the case of the test from May 1st (above fourteen hours day length), even if the test plants were stayed under short-day condition for more than 10 days, they were not able to mature, but flowerd. From the test of Apr. 15th, day length of thirteen hours, the plants were showed variable reaction to the short-day treatment. In this test, 11days for short-day treatment was a basic day to decide whether flowering was delayed or not. In the test from Apr. 1st, perilla seeds were able to harvest at least 5 days short-day treatment. In the final test from Mar. 15th, it had no need to take short-day treatment for harvesting of normal seeds, because the day length of that are twelve hours, which is an enough time to induce flowering and maturing, previously reported.

• PNF and Movement
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• 제1권1호
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• pp.11-18
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• 2003

Objectives: Few studies have reported on the flexibility of the hamstrings resulting from variable stretching method, and little studies of length adaptation at 1 day after intervention. Methods: Fifty-four healthy a woman in her twenties with no history of musculoskeletal or neurogenic disorder volunteered for this study. Subjects were randomly assigned to either a contract-relax group or a passive stretching group. Methods: Hamstring flexibility was measured with a sit and reach test(SRT) (RF-D18; SPC) before, immediatly after interventions, and 1 day after interventions. Results: Flexibility scores for participants in each of the groups significantly increased from pre-interventions to immediate and 1 day after interventions. However, the length of 1 day after interventions was shorter than immediate length after interventions. Difference in length between immediate and 1 day after interventions was some shorter in the contract-relax group versus the static group but, not significantly. Conclusions: The results of this study suggest that a contract-relax is an effective length adaptation of hamstring muscles by 1 day after intervention.

• 한국작물학회지
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• 제35권1호
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• pp.10-15
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• 1990

전보에서 파종기 이동에 따라 5가지의 종실중변이 유형을 찾을 수 있었다. 그중에서도 파종이 늦을수록 점차 종실중이 감소하는 제I유형, 파종기와는 무관하게 종실중변이가 없는 제II유형 및 파종이 늦을수록 점차 종실중이 증가하는 제III유형의 품종들에 대해 일장조건이 주요형질과 종실중변이에 미치는 영향을 검토하였던 바 그 결과는 다음과 같다. 1. 처리일장이 길어질수록 개화일수, 개화시엽수, 경장 및 주경절수는 점차 증가하였고 24시간 일장에서 KLS 714-1, KLS 405-1, 밀태는 개화하지 않았다. 2. 일장조절시 종실중과 개화일수, 개화시 엽수, 경장, 주경절수간에는 대체적으로 부의 유의상관이었는데 그중 개화일수와의 사이에 가장 높은 상관을 보였다. 3. 일장조절시 종실중변이는 제I유형인 영광과 외알콩에서 일장조건에 따라 종실중이 14시간까지는 증가하다가 16, 24시간 일장에서는 점차 감소하였고, 제II유형인 청수는 대체적으로 일장이 길어짐에 따라 점차 감소하였으나 KLS 714-1은 14시간 일장까지는 증가하다가 16, 24시간에서는 감소하였으며 제III유형인 KLS 405-1, 밀태는 일장이 길어짐에 따라 점차 감소하여 일장처리에 따른 품종별 종실중변화는 파종기 이동시 종실중의 변이유형과 유사하였다.

• Journal of Astronomy and Space Sciences
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• 제30권1호
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• pp.33-41
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• 2013

Various features of the existing perturbations in the Earth's spin rotation are investigated for the recent and most reliable data by spectral analysis, filtering, and comparison with idealized model. First, theory of Earth's spin rotational perturbation is briefly re-derived in the Earth-fixed coordinate frame. By spectral windowings, different periodic components of the length of day perturbation are separated, and their characters and excitations are discussed. Different periodic components of polar motion are acquired similarly and described with further discussion of their excitations. Causes of the long time trends of both the length of day and polar motion are discussed. Three possible causes are considered for the newly discovered 490-day period component in the polar motion.

• 한국작물학회지
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• 제65권3호
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• pp.241-247
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• 2020

온도와 일장처리를 달리하여 참깨 개화, 생육특성 및 수량성에 미치는 영향을 구명하고자 2019~2020년 2년에 걸쳐 수행하였으며, 그 결과를 요약하면 다음과 같다. 1. 단일조건(12시간)에서 온도 증가에 따른 참깨 품종의 개화일수 단축정도는 90일깨가 11일, 풍성깨가 10.5일, 아름깨가 10일이었으며 고온조건(28℃)에서 일장이 길어 질수록 참깨품종의 개화지연일수는 90일깨가 7.5일, 안산깨와 양백깨가 각각 9일, 풍성깨가 14.5일, 성분깨가 15일, 아름깨가 18일로 나타났다. 2. 개화일수와 경장, 주당삭수, 천립중, 10a당 수량간에는 부의 상관관계를 나타내었는데 개화소요 일수가 길어 개화가 늦어지면 생식생장기간이 줄어들고 수량관련 형질들의 기본특성을 확보할 수 있는 기간이 부족해진다. 3. 일장과 온도에 따른 품종 간 수량성 변화를 보면 안산깨, 아름깨는 온도가 높아질수록 수량이 감소하였으나 양백깨, DT45는 증가하는 경향을 나타내었다. 일장이 길어질수록 수량은 감소하는 경향을 나타났으며 참깨 품종간 반응을 다양하게 나타났다. 4. 풍성깨, 성분깨는 파종기를 앞당겨서 조기파종에 적합하였으며 DT45, 풍성깨, 90일깨, 안산깨, 성분깨는 파종기를 늦추어 만파를 할 경우 적합하였다. 양백깨와 아름깨는 5월 상순부터 중순까지 파종을 하였을 경우 수량성 확보에 유리하였다.

• Journal of Ecology and Environment
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• 제45권2호
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• pp.78-87
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• 2021

Background: To understand shade and wind effects on seedling traits of common reed (Phragmites australis), we conducted a mesocosm experiment manipulating day length (10 h daytime a day as open canopy conditions or 6 h daytime a day as partially closed canopy conditions) and wind speed (0 m/s as windless conditions or 4 m/s as windy conditions). Results: Most values of functional traits of leaf blades, culms, and biomass production of P. australis were higher under long day length. In particular, we found sole positive effects of long day length in several functional traits such as internode and leaf blade lengths and the values of above-ground dry weight (DW), rhizome DW, and total DW. Wind-induced effects on functional traits were different depending on functional traits. Wind contributed to relatively low values of chlorophyll contents, angles between leaf blades, mean culm height, and maximum culm height. In contrast, wind contributed to relatively high values of culm density and below-ground DW. Conclusions: Although wind appeared to inhibit the vertical growth of P. australis through physiological and morphological changes in leaf blades, it seemed that P. australis might compensate the inhibited vertical growth with increased horizontal growth such as more numerous culms, indicating a highly adaptive characteristic of P. australis in terms of phenotypic plasticity under windy environments.

• 대한임상전기생리학회지
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• 제6권1호
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• pp.43-55
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• 2008

The purpose of this study was to investigate the effect of microcurrent stimulation intensity($50{\mu}A,\;100{\mu}A,\;300{\mu}A$ - 5 pps pulse frequency was same) on wound healing in rat. Sixty male Korean rats were randomly divided into 4 groups of 15 for 4 different treatment protocols(none-control group, $50{\mu}A,\;100{\mu}A,\;300{\mu}A$ experimental groups). Experimental 20 mm linear wound were made and all animals in the experimental groups were received microcurrent stimulation once a day for 20 minutes until sacrifice days(1st day, 3rd day, 6th day). A vernier caliper was used to measure a wound healing length and an optical microscope was used to determine any histological changes. The repeated measures two-way ANOVA was used for statistical differences in wound healing length. Experimental results were as follows: 1. In the examination with the naked eye, all groups showed similar changes until 1st day. But from 3rd day, a little intercellular fluid soaked through wound region in control group. In experimental groups, little intercellular fluid soaked through wound region, and swelling and redness did not appear. 2. Wound length of experimental $50{\mu}A$ group was significantly decreased than control group(p<0.001). And in the aspect of application period, wound length was significantly decreased in 3th, 6th day than 1st day and 6th day than 3th day (p<0.001). In conclusion, it has been found that the microcurrent stimulation had a positive effect on wound healing. And $50{\mu}A$ stimulation intensity was more effective than other intensities($100{\mu}A,\;300{\mu}A$) in wound healing. Also, low-intensity microcurrent stimulation was more effective on the purpose of wound healing.

• 한국발생생물학회지:발생과생식
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• 제14권1호
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• pp.21-25
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• 2010

Nile tilapia (Oreochromis niloticus) are mouth-brooders so that the females holding eggs in their mouth sacrifice their somatic growth for reproduction. For this reason, artificial control of reproduction for the culture of this species has been of interest. Manipulation of photoperiod is an emerging technique for such purpose, but little information is available to establish appropriate photoperiod regime. To obtain necessary basic information, sexually mature females were individually accommodated to glass aquarium, and the spawning activity of these females were monitored for two years under natural photoperiod regime. Female tilapia spawned most frequently on March, April and May when the day length gradually increased from 11 hours to 14 hours and least frequently on September, October, November and December when the day length gradually decreased from 13 hours to less than 10 hours in the first year. The decrease of spawning frequency as day length decreased was also observed in the second year, although the increase of spawning frequency as day length increased was less clear. Spawning of female tilapia was less active when the night was dark due to the disappearance of moonlight (Dark Phase), compared to the Phase of Getting Lighter, Light Phase and Phase of Getting Darker. Results from this study suggest that long day length, particularly increasing phase, is favoured for active spawning of Nile tilapia, and that this species, as a tropical fish species, may utilize changing lunar phases as a secondary environmental cue for reproduction.

• 한국작물학회지
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• 제51권1호
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• pp.41-47
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• 2006

To understand the heading habit of recently developed 20 Korean rice cultivars, rice plants in a phytotron were exposed to different temperature: $22.5^{\circ}C(day\;27^{\circ}C/night\;18^{\circ}C),\;27.5^{\circ}C(day\;32^{\circ}C/night\;23^{\circ}C)$, and day-length conditions: 10, 12, 13, 14, 15 hours. Four rice cultivars (Sobibyeo, Juanbyeo, Ilpumbyeo and Shindongjinbyeo) showed relatively short Basic Vegetative Phase (BVP) of 17 to 18 days, while Dasanbyeo showed the longest (35 days) BVP, compared to other remaining 15 tested cultivars which exhibited 24 to 31 days of BVP. In this experiment, it was tried out to separate the eliminable vegetative phase into photosensitivity and thermo-sensitivity with two different pathways. Many tested cultivars, however, exhibited quite different responses under low temperature and / or long day-length conditions. Especially, Surabyeo and Juanbyeo were the most difficult cultivars to separate into photo- or thermo-sensitivity in that the eliminable vegetative phase of these two cultivars increased greatly only under low temperature $(22.5^{\circ}C)$ and long day-length (15 hr.) conditions. Regarding the heading response to temperatures, tested cultivars could be categorized into 2 groups. In 1st group of rice cultivars, the eliminable vegetative phase decreased almost equally as the temperature changed from $20.0^{\circ}C\rightarrow22.5^{\circ}C\rightarrow25.0^{\circ}C\rightarrow27.5^{\circ}C$. In contrast, the 2nd group of rice cultivars exhibited eliminable vegetative phase slowly decreasing when the temperature changed from $22.5^{\circ}C\rightarrow25.0^{\circ}C\rightarrow27.5^{\circ}C$, but rapidly decreasing when the mean temperature changed from $20.0^{\circ}C\;to\;22.5^{\circ}C$. All the cultivars belonged to 2nd group, the heading date would be very delayed if cool summer comes.