• 한국발생생물학회지:발생과생식
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• 제25권4호
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• pp.293-298
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• 2021

Di(2-ethylhexyl)phthalate (DEHP) could induce metabolic disorders through interfering with thyroid homeostasis. Therefore, we evaluated the effects of short term to environmental relevant doses of DEHP on thyroid hormones. Four week old Sprague-Dawley (SD) rats were treated with vehicle (corn oil), and DEHP 0.75, 7.5, and 150 mg/kg/day. The rats were treated with once daily by oral gavage and were sacrificed with after 1 week. They were measured body weight and relative thyroid weight, serum thyroid hormones and histological changes of thyroid. There was no difference in body weight between the control and DEHP exposed rats. Relative thyroid weight in DEHP 150 mg/kg/day treated group was significantly lower than control. Serum thyroxine levels was decreased in rats exposed to 0.75 and 150 mg/kg/day DEHP. No histological changes were observed in the thyroid of rats administered DEHP compared to control. Exposure to DEHP at environmental relevant levels, even short-term exposure, can cause hypothyroidism in adolescent rats even the exposure period is relative short.

• Plant Biotechnology Reports
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• 제4권2호
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• pp.117-123
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• 2010

We used a flow cytometer to investigate the variations in endopolyploidy (the frequencies of nuclei with DNA contents equivalent to 4C through 16C) during the short period of the early growing stage in vigorously growing young tissues of maize seedlings. We examined different portions of the root and leaves that had been growing for 7 (day 7) and 13 (day 13) days after germination. Endoreplication showed two opposing phenomena without aging. In one case, the endopolyploidy of the first leaf was higher on day 13 than on day 7. In the latter case, endopolyploidy decreased, as clearly revealed by a comparison of the endopolyploidy of the second leaves and the 160-170 mm portion of the seminal root on days 7 and 13. Endopolyploidy was also lower in the top of the leaf. In roots, endopolyploidy was increased by the exogenous application of abscisic acid for only 1 day. The levels of endopolyploidy increased without an increase in cell size in the roots. These results showed that endoreplication occurs in actively growing and young tissue and that the variation can be induced in the short period examined.

• 대한후두음성언어의학회지
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• 제11권1호
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• pp.64-68
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• 2000

Background and Objectives : To assess the role of altered vocal function in transient voice change after short-term endotracheal intubation, we evaluated acoustic parameters, aerodynamic parameters, and laryngoscopic characteristics preoperatively and postoperatively. Materials and Methods : Vocal function of 10 patients undergoing tympanoplasty and mastoidectomy using general anesthesia and endotracheal intubation were studied preoperatively, at 1day and 7 days after extubation. Acoustic analysis, aerodynamic study, and telescopic examination were used to assess vocal function. Results : In acoustic parameters, there was no significant difference between preoperative and postoperative measures. However, in subglottic pressure, ere was a significant decrease at 1 day after extubation and this change was return to preoperative value at 7 days after extubation. MPT(Maximal Phonation Time), MER(Mean flow Ratio), and VC(Vital Capacity) were decreased 1 day after extubation but did not show statistically significant change. Three of 10 patients manifested a vocal fold edema and injection 1 day after extubation. Conclusions : Subglottic pressure revealed a significant decrease at 1 day after extubation. And this change was correlated with laryngeal morphologic change and decrement in pulmonary function.

• 한국연초학회지
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• 제16권2호
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• pp.108-112
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• 1994

Response of two ploidy levels to cool temperature and short day treatment were investigated under controlled conditione of Phytotron. The haploid and diploid of seven genotypes were started and grown to the 8- leaf stage in the greenhouse. They were treated during 15 and 20 days to 8- hour photoperiods at 18$^{\circ}C$ in controlled - environmental room to induce premature flowering, respectively. Diploid plants of seven genotypes flower later than their haploid plants at 20 days treatment. But under 15 days treatment, diploid plants of NC82, Hicks, BY4, NC2326 and Coker86 were not different from their haploid plants for days to flower. Diploid plants of seven genotypes developed the same number of leaves as their haploid plants at 20 days treatment. Under 15 days treatment, diploid plants of Coker347 and NC95 developed more leaves per plant than their haploid plants. Correlation coefficient between the ranks of leaves per plant of seven genotypes at two ploidy levels was 0.964 and 0.929 at 15 and 20 days treatment, respectively.

• 한국연초학회지
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• 제18권2호
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• pp.132-137
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• 1996

This experiment was conducted to investigate varietal responses to cool temperature (18℃) and short photoperiod (8 hours a day) in a controlled room of phytotron. Five burley tobacco varieties (Nicotiana tabacum L.), Awelius (very early flowering type), Burley 21 and KB 103 (medium), Banket Al and MB 1 (slightly late) and TC 681 (late) were compared in number of leaves per plant and day to flower in different treatment periods (10, 15, 20, 25 and 30 days). The days to flower decreased significantly than the control (in the phytoron with 14hr photoperiods and a minimum temperature 20'c) when the treatment periods were over 15 days for the varieties Aurelius, Burley 21 and KB 103, and 20 days for TC 681, and 30 days for Banket Al, respectively. And also the number of leaves decreased significantly than that of the control when the periods of treatment were over 10 days for Burley 21 and Aurelius, 15 days form 103, and 20 days for TC 681 and Banket Al, and 30 days for MB 1, respectively. The decreasing ratio in the number of leaves per plant under cool temperature and short photoperiod treatments was the lowest in Banket Al and MB 1. Key words : Nicotiana tabacum, cool temperature, short photoperiod.

• 조명전기설비학회논문지
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• 제27권6호
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• pp.17-22
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• 2013

Fuzzy linear regression method has been used for short-term load forecasting of the special day in the previous researches. However, considerable load forecasting errors would be occurring if a special day is located on Saturday or Monday. In this paper, a new load forecasting method for the consecutive holidays is proposed with the consideration of the power demand variation rate. In the proposed method, a exponential smoothing model reflecting temperature is used to short-term load forecasting for Sunday during the consecutive holidays and then the loads of the special day during the consecutive holidays is calculated using the hourly power demand variation rate between the previous similar consecutive holidays. The proposed method is tested with 10 cases of the consecutive holidays from 2009 to 2012. Test results show that the average accuracy of the proposed method is improved about 2.96% by comparison with the fuzzy linear regression method.

• 농업과학연구
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• 제42권4호
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• pp.447-453
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• 2015

Increase of national family income improved demand of high-quality and year-round horticultural products including chrysanthemum. To meet these demand, farmers have introduced protected facilities, such as greenhouses, of which environmental conditions could be monitored and controlled. Environment management up to three weeks after transplanting is critical for chrysanthemum quality. Artificial lighting and light-blocking screen are especially important for long-day (day period > 13 hours) and short-day (night period > 13 hours) treatments. In this study, a web-camera was installed, and the image was obtained and transmitted to mobile phones to monitor the status of 3-wavelength(RGB) lighting environments. RGB pixel values were used to determine malfunctioning of the lighting lamps, and leaking out and incoming illumination status during short-day and long-day treatment periods. Normal lighting lamps provided RGB pixel values of 240~255. During long-day treatment period, G pixel values were useful to detect abnormal lighting conditions (e.g., leaking). During short-day treatment period, R pixel values were useful to determine incoming light (e.g., sun-light). Results of this study would provide useful information for remote monitoring of light conditions for protected chrysanthemum production under artificial lights.

• 대한의생명과학회지
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• 제15권3호
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• pp.217-227
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• 2009

The present study was set to evaluate the effect of pomegranate extracts on improvement of the menopausal syndromes such as face flushing in ovariectomized rats by carrying out short- and long-term experiments. Pomegranate extracts used to feed rats were prepared from the pulp part which does not contain the rid of the pomegranate, and were dissolved in propylene glycol. From the short-term (16 days) experiment, it was clear that when the 25, 250, 1,250 mg/kg/day concentrations of pomegranate extracts were orally fed to ovariectomized rats, the body temperature of the rats in all the 3 groups were decreased with statistical significance compared to other control groups which were fed with propylene glycol only. Especially, the body temperature decreased by $2.7^{\circ}C$ compared to control groups even when the pomegranate extracts were fed at the low concentration of 25 mg/kg/day implying the usefulness of pomegranate extracts in improving face flushing troubles. In addition, the body weight of the groups fed with pomegranate extracts also decreased when compared to groups fed with only propylene glycol, and the results were also statistically significant. In case of the estradiol level in the blood of rats, the levels were somewhat higher in the groups fed with pomegranate extracts than the control groups, even though the difference was not statistically significant. As found from the results of the short-term experiment, in long-term experiment, the groups fed with pomegranate extracts showed statistically significant decrease in the body temperature and the body weight, whereas the increase of the estradiol levels in blood in each groups were statistically insignificant. During the short- and long-term experiments, no sign of toxicity was found in rats fed with pomegranate extracts indicating no toxic side effects of the pomegranate extracts when orally fed. The concentrations of pomegranate extracts 25, 250, 1250 mg/kg/day treated to ovariectomized rats in this study can be estimated to be 1.5, 15, and 75 g/day when treated to women whose body weight is 60 kg which is average for women with menopausal syndromes. Since even the 75 g/day of high concentration of pomegranate extracts did not show any toxicity in short- and long-term experiments, taking 1.5 g/day concentration of pomegranate extracts would be safe dose for not causing any side effects. Therefore, it can be concluded from the results of this study that taking 1.5 g/day of pomegranate extracts for certain period time will improve the menopausal syndromes including face flushing.

• 한국잡초학회지
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• 제16권4호
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• pp.301-308
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• 1996

파대가리 근경(根莖)의 번식특성과 종자형성에 관련한 일장반응(日長反應) 특성을 조사하기 위하여 수행한 일련의 실험결과를 요약하면 다음과 같다. 1. 근경(根莖)의 발생양상을 보면 신초엽(新稍葉)이 4매정도 출현할 때 기부엽액(基部葉腋)에서 2-3개의 1차 근경(根莖)이 나오며 이들이 지표면을 따라 뻗어가면서 신장되었고, 1차 근경(根莖) 각 마디에서 신초(新稍)가 발생되어 이로부터 다시 2-3개의 2차 근경(根莖)이 발생되었다. 이와 같은 번식특성으로 눈이 하나가 달린 근경절편(根莖切片)을 1년동안 생육시키면 5차 근경(根莖)까지 발생되고, 신초수(新稍數)도 대략 688개나 되었다. 2. 한 개의 눈을 가진 근경절편(根莖切片)으로부터 형성된 영양번식체는 종자 한 개로부터 형성된 것에 비하여 약 3배정도, 종자형성량의 경우는 2.5 배정도 많은 경향이었다. 천립중(千粒重)을 기준한 종자의 충실도는 8월 전후에 발생된 개체에서 가장 좋았다. 3. 파대가리는 대략 14시간 이하의 단일조건(4월 중하순 이전과 7월 중하순 이후)에서 생식생장으로 전환되며, 각 신초(新稍)는 단일에 대해 독립적으로 반응하되 잎이 2-3매 출현되었을 무렵 7회 이상의 단일주기를 접했을때 화성(花性)이 유도되는 경향이었고, 화성(花性)이 유도될 수 있는 단일조건하에 식물체가 자랄지라도 최소한 4매의 옆이 발생된 이후에 화기(花器)가 출현되었다. 4. 지베렐린($GA_3$) 처리는 단일조건에 생육된 개체들의 출수(出穗)를 3일 정도 촉진시켰지만 장일 조건에서 생육된 경우에는 출수유기(出穗誘起)에 전혀 영향을 주지 못했다.

• 대한원격탐사학회지
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• 제27권3호
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• pp.259-276
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• 2011

Short-term land cover changes, such as forest fire scar and crop harvesting, can be detected by high temporal resolution satellite imagery like MODIS and AVHRR. Because these optical satellite images are often obscured by clouds, the static cloud-free composite methods (maximum NDVI, minblue, minVZA, etc.) has been used based on non-overlapping composite period (8-day, 16-day, or a month). Due to relatively long time lag between successive images, these methods are not suitable for observing short-term land cover changes in near-real time. In this study, we suggested a new dynamic cloud-free composite algorithm that uses cut-and-patch method of cloud-masked daily MODIS data using MOD35 products. Because this dynamic composite algorithm generates daily cloud-free MODIS images with the most recent information, it can be used to monitor short-term land cover changes in near-real time. The dynamic composite algorithm also provides information on the date of each pixel used in compositing, thereby makes accurately identify the date of short-term event.