• Journal of Radiation Protection and Research
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• v.23 no.1
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• pp.17-23
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• 1998

Dose response relationships for one of biological end-points (gene mutation) in somatic cells of Tradescantia 4430 clones were studied using neutrons coming out of a californium-252 isotopic source. And the relative biological effectiveness (RBE) of neutrons in relation to X-rays in the induction of TSH pink mutations was assessed. Inflorescences were irradiated with X-ray from X-ray generator and neutrons from $^{252}Cf$ source. Irradiated cuttings were incubated with aeration in neutrient solution under the controlled condition. For more than 4 weeks after irradiation cell mutations were scored. Pink mutation frequencies were calculated from the pooled data for the peak interval (days 6 to 13 post-irradiation). Somatic cell mutations in TSH showed linear dose response relationships in the range of neutron doses available for the experiment. The RBE values estimated for neutrons in relation to X-rays were in the range 3.1 to 6.8, which were much lower than normally recognized value.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.359-366
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• 2016

Tradescantia is a perennial plant in the family of Commelinaceae. It is known to be sensitive to radiation. In this study, Tradescantia BNL 4430 was irradiated with gamma radiation at doses of 50 to 1,000 mGy in a phytotron equipped with a $^{60}Co$ radiation source at Korea Atomic Energy Research Institute, Korea. At 13 days after irradiation, we extracted RNA from irradiated floral tissues for RNA-seq. Transcriptome assembly produced a total of 77, 326 unique transcripts. In plantlets exposed to 50, 250, 500, and 1000 mGy, the numbers of up-regulated genes with more than 2-fold of expression compared that in the control were 116, 222, 246, and 308, respectively. Most of the up-regulated genes induced by 50 mGy were heat shock proteins (HSPs) such as HSP 70, indicating that protein misfolding, aggregation, and translocation might have occurred during radiation stress. Similarly, highly up-regulated transcripts of the IQ-domain 6 were induced by 250 mGy, KAR-UP oxidoreductase 1 was induced by 500 mGy, and zinc transporter 1 precursor was induced by 1000 mGy. Reverse transcriptase (RT) PCR and quantitative real time PCR (qRT-PCR) further validated the increased mRNA expression levels of selected genes, consistent with DEG analysis results. However, 2.3 to 97- fold higher expression activities were induced by different doses of radiation based on qRT-PCR results. Results on the transcriptome of Tradescantia in response to radiation might provide unique identifiers to develop in situ monitoring kit for measuring radiation exposure around radiation facilities.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.371-372
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• 2003

서울의 지하철은 하루 450만 명 정도를 수송하는 중요한 대중교통 수단이다. 지하철 역사 내의 실내 환경에 대한 실내공기질 관리는 실내공기 오염의 대상물질에 대한 특정유해물질과 같은 단일 물질에 대한 지표에 의해 관리되고 있다. 그러나 공기중 입자상 물질의 특성은 복합적이기 때문에 공기질에 대한 관리는 여러 제한점을 가지고 있다. 또한 역구내의 먼지에 대한 단순 측정ㆍ분석만이 이뤄지고 있을 뿐 그 먼지의 생물학적 영향에 대한 연구는 미흡한 실정이다 본 연구에서는 지하철역 구내에서 포집한 미세먼지가 돌연변이원을 함유하고 있는 지를 여름과 겨울철에 대한 비교 평가하였다. (중략)

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.89-92
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• 2004

The effects of different light quality on the change of membrane potential difference (PD) of the guard cell in the intact leaf have been investigated. The mombrane PD was about -5.5 mV by white light of 600 $\mu$moles $m^{-2}\; s^{-1}$. The mean PD of change caused by red light was about -5.2 mV at the light intensity of 80 $\mu$moles $m^{-2}\; s^{-1}$. Membrane PD of guard cells in response to blue light was saturated at low light intensity. However, red and green light enhanced the change of membrane PD of guard cells with increasing intensity. In green light the biggest change of memrane PD was around -4 mV, whereas, with blue light the change of of memrane PD was around -2 mV. Accordingly, the membrane PD of guard cell showed the different degree of hyper-polarization by each wavelength.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.461-462
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• 2003

산업의 발달과 함께 자연의 자정능력 한계를 넘어선 오염은 인간의 생존을 위협하는 심각한 사회문제로 대두되기에 이르렀다. 지금까지 대기오염에 대한 관심은 주로 실외대기, 즉 건물의 바깥쪽에 있는 대기오염에 편중되어 있었다. 대도시 및 중ㆍ소 공업 도시 등 대기오염이 문제되는 지역에서의 하루 생활은 하루 24시간 중 80％이상을 실내 공간에서 생활하고 있어 다양한 직업을 가진 현대인은 개인에 따라 다소 차이가 있지만 대기오염의 영향보다는 하루 중 많은 시간을 보내는 실내오염의 영향을 더 많이 받는다. (중략)

• Natural Product Sciences
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• v.15 no.1
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• pp.8-11
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• 2009

Blood glucose lowering effects of water extracts from four species of Commelinaceae(Commelina communis, Streptolirion volubile, Tradescantia reflexa, Aneliema keisak) were determined on alloxan-induced hyperglycemic rats. In all the experimental groups, the blood glucose level decreased after loading carbohydrates. The blood glucose level in a group treated with C. communis extract decreased significantly as compared with the normal group. After loading maltose and sucrose separately in different groups, the blood glucose level decreased in the groups treated with the extracts of C. communis and S. volubile, and remained approximately unchanged with the extracts of T. reflexa and A. keisak as compared with the control groups.

• Journal of Plant Biology
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• v.36 no.4
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• pp.383-389
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• 1993

The effects of light and $CO_2$ on the electrophysiological characteristics of guard cells in the intact leaf and in the detached epidermis have been investigated. Guard cells in intact leaves showed the membrane hyperpolarization in response to light. The biggest induced change of the membrane potential difference (PD) in the guard cells of the intact leaf was 13 m V by light and 42 mV by $CO_2$ in Commelina communis. Similar results were obtained with Tradescantia virginiana. However, there were no changes of membrane PD in detached epidermis. In order to determine the influence of the mesophyll on the changes of membrane PD, infiltration of the mesophyll cells with photosynthetic inhibitors was performed. In CCCP infiltrated leaf discs the guard cell membrane was depolarized slightly by red-light and hyperpolarized by $CO_2$, but in leaf discs infiltrated with DCCD and DCMU the guard cell membrane was hyperpolrized by both red-light and $CO_2$ as the control leaf discs. In azide infiltrated leaf discs the guard cell membrane showed no response to light and there was a much reduced membrane hyperpolarization by $CO_2$ compared to other responses. It was likely that azide caused leaf damage and the activity of cell metabolism was decreased greatly, resulting in small membrane PD changes by $CO_2$ and no changes by redlight. Therefore, it can be suggested that red light was sensed by the mesophyll and the light induced guard cell membrane hyperpolarization was related to energy produced by cyclic-photophosphorylation, but ${CO_2}-induced$ guard cell membrane hyperpolarization was not related to photosynthesis. Alkalisation of the vacuole was observed when the intact leaf was exposed to $CO_2$, indicating that membrane hyperpolarization was mainly the result of proton efflux.efflux.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.373-378
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• 2011

Our aim was to investigate the genotoxicity of ambient air in the Krak$\acute{o}$w area after Fukushima Nuclear Power Plant (NPP) accident and compare with results from Chernobyl fallout. For the detection of ambient air genotoxicity the technique for screening gene mutation frequency in somatic cells of the $Tradescantia$ stamen hairs ($Trad$-SH assay) was used. Since 11th of March 2011 (Fukushima NPP accident), several pots containing at least 15 shoots of bioindicating plants were exposed to ambient air at 2 sites in the Krak$\acute{o}$w surrounding area, one in the city center, and about 100 pots in a control site (in the glasshouse of the Institute of Nuclear Physics) Continuous screening of mutations was performed. Progenies of 371,090 cells exposed were analyzed. Mutation frequency obtained in the first 10 days has shown a mean control level (GMF*100=$0.06{\pm}0.01$). At scoring period related to influence of a potential Fukushima fallout, a significant increase of gene mutation frequencies above the control level was observed at each site in the range, 0.10~0.33 depending on the location, (mean value for all sites GMF*100=$0.19{\pm}0.05$) that was associated with a strong expression of toxic effects. In the reported studies following the Chernobyl NPP accident monitoring $in$ $situ$ of the ambient air genotoxicity was performed in the period since April $29^{th}$ till June $3^{rd}$ 1986 also with Trad-SH bioindicator. In general, mutation frequency increases due to Chernobyl fallout(GMF*100=$0.43{\pm}0.02$) were corresponding to fluctuation of radioactivity in the air reported from physical measures, and to published reports about increase in chromosome aberration levels. Although, recent data obtained from monitoring of the ambient air quality in the Krak$\acute{o}$w and surroundings are lower when compared to results reported after Chernobyl NPP accident, though results express a significant increase above the control level and also are corresponding with increased air radioactivity reported from physical measurements. Statistically significant in comparison to control increase in gene mutation rates and more prolonged than that after Chernobyl fallout increase of GMF was observed during the period following the Fukushima NPP failure.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.447-456
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• 2013

This study was carried out for the establishment of theory and foundational data for breeding, on variegated foliage plants using for potted plants, based on examination and analysis for shape, color, and area ratio of variegated leaves and chlorophyll contents. Six families, 18 genus, and 54 species of variegated plants domestically distributed in Korea were used as the plant materials. Patterns based on chlorophyll-deficient part in variegated leaves were divided into 20 types, such as steps, border, collapsed border, sandy border, half, silk, stars, vein, firewood, border and firewood, center, entirety, leaf, irregular, net, watermelon, melon, and so on. There were 10 kinds of colors including dark green, red, dark red, reddish white, reddish yellow, white, silver, silvery white, yellowish white, and yellow. The ratio of variegated area was ranged from 5.8% to 100% and it was diverse depending on species or cultivar. The ratios by patterns were highest in entirety (98.6%) and relatively high in step (60.8%), whereas, low in boarder, star and firewood (33.6-36.4%), and relatively low in half and vein (43%). Chlorophyll content of variegated leaf was rather lower compared to normal plants and chlorophyll b tended to be higher in ratio of chlorophyll a to b. Particularly content of chlorophyll b in Stromanthe sanguinea 'Triostar', Dracaena fragrans 'Massangeana Compacta', D. reflexa 'Song of India', and Tradescantia spathacea was higher than chlorophyll a in comparison with that of normal plants.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.3
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• pp.719-731
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• 2017

The aim of this study was to analyze a group of pre-service elementary teachers experience on the cognitive terms of biology inquiry subjects, and experience on living materials related with the domain of life in the Korea elementary school science textbook. Firstly, elementary school pre-service teachers had the confidence of inquiry subjects related with the domain of life such as 'when we take breath what will happen in human body?' and 'Can we make the model of human body?' But they did have the most diffidence of 'The search for pieris rapae, a cabbage butterfly's life', 'Can we grow the little creature?' The reason why pre-service elementary teachers had diffidence of comprehending experiment procedure and planning ability was that 'they focused on understanding the scientific concepts instead of planning experiments by themselves', and 'they carried out the least amount of experiments' Secondly, elementary school pre-service teachers had never experienced biology materials related with the domain of life in the Korea elementary school biology science textbook such as 'tradescantia reflexa', 'Caddis larva', 'hydrilla verticillata', and 'Plantain lily.' According to the findings obtained from the study, the reason why they had never seen the biology materials was that they had the least opportunity of immediately observing life creatures due to memorization-intensive classes.