• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.280.1-280.1
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• 2016

Generally InGaN/GaN green light emitting diode (LED) exhibits the low quantum efficiency (QE) due to the large lattice mismatch between InGaN and GaN. The QE of InGaN-based multiple quantum wells (MQWs) is drastically decreased when an emission wavelength shifts from blue to green wavelength, so called "green gap". The "green gap" has been explained by quantum confined Stark effect (QCSE) caused by a large lattice mismatch. In order to improve the QE of green LED, undoped graded short-period InGaN/GaN superlattice (GSL) and Si-doped GSL (SiGSL) structures below the 5-period InGaN/GaN MQWs were grown on the patterned sapphire substrates. The luminescence properties of InGaN/GaN green LEDs have been investigated by using photoluminescence (PL) and time-resolved PL (TRPL) measurements. The PL intensity of SiGSL sample measured at 10 K shows stronger about 1.3 times compared to that of undoped GSL sample, and the PL peak wavelength at 10 K appears at 532 and 525 nm for SiGSL and undoped GSL, respectively. Furthermore, the PL decay of SiGSL measured at 10 K becomes faster than that of undoped GSL. The faster decay for SiGSL is attributed to the increased wavefunction overlap between electron and hole due to the screening of piezoelectric field by doped carriers. These PL and TRPL results indicate that the QE of InGaN/GaN green LED with GSL structure can be improved by Si-doping.

• Journal of Life Science
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• v.28 no.9
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• pp.1081-1091
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• 2018

The purpose of this study was to investigate the structure and the glycoconjugate properties of the olfactory mucosa in the rat after inhalation of xylene. Sprague-Dawley male rats were inhalated 300 ppm xylene for 5 times with 5 hours exposure. The olfactory mucosa in the nasal cavity was taken from the animals on 5, 10, 15, 20, and 30 days after inhalation of xylene. The properties of the glycoconjugates in the olfactory mucosa were investigated using 10 biotinylated lectins: (PSA, UEA I, PHA-L, GSL I B4, GSL I, PNA, ECL, SBA, GSL II, and sWGA). In the experimental groups, degenerative changes of the olfactory epithelium were observed until 20 days after inhalation of xylene. In the control group, the olfactory cells in the olfactory epithelium reacted with PSA, UEA I, PNA, SBA, and sWGA, the supporting cells reacted with PSA, PHA-L, GSL I, PNA, ECL, SBA, GSL II, and sWGA, and the Bowman's glands reacted with all 10 lectins. In the experimental groups, the reactivity to PSA, PNA, and SBA in the olfactory cells were decreased, and the reactivity to PSA, PNA, SBA, and GSL II in the supporting cells were decreased. And in the Bowman's gland, the reactivity to PSA, UEA I, GSL I, and sWGA were decreased. Conclusively, the olfactory mucosa was shown a lot of changes in the structure through degenerative process and in the properties of the glycoconjugates after inhalation of xylene. These results suggest that the sugar residues of the glycoconjugates in the olfactory mucosa can be changed by xylene inhalation.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.177-185
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• 2015

The aim of this study was to investigate the amounts of glucosinolates (GSL) in kale at various development stages. Kale varieties 'Manchoo Collard' and 'TBC' were cultivated from 20 February 2012 to 3 July 2013 in the greenhouse at Chungnam National University. During the cultivation periods, samples were harvested at 35, 63, 91, 105, 119, and 133 days after sowing (DAS) and the amount of GSL quantified by HPLC. Ten types of GSL (progoitrin, sinigrin, glucoalyssin, gluconapin, glucoiberverin, 4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, gluconasturtiin, and neoglucobrassicin) were observed in 'TBC', whereas nine types of GSL (the same as above, except glucoiberverin) were identified in 'Manchoo Collard'. The amount of total GSL in 'Manchoo Collard' was comparatively higher at 133 DAS (mean $8.64{\mu}mol{\cdot}g^{-1}$) and lower at 35 DAS ($1.16{\mu}mol{\cdot}g^{-1}$ dry weight, DW) of cultivation. In the case of 'TBC', the amount of GSL was higher at 91 DAS (mean $13.41{\mu}mol{\cdot}g^{-1}$) and lower at 35 DAS ($0.31{\mu}mol{\cdot}g^{-1}$ dry weight, DW). Sinigrin was the most abundant GSL (57% of total GSL) in 'Manchoo Collard' at 133 DAS and was also highest (44%) in 'TBC' at 91 DAS. Together, progoitrin, sinigrin, glucobrassicin, and gluconasturtiin, the precursor of crambene, allylisothiocyanate, indol-3-cabinol, and phenethylisothiocyanate accounted for 94 and 78% of GSL in 'Manchoo Collard' and 'TBC', respectively. Our results demonstrate that the amounts of GSL, which have potential anti-carcinogenic activity, change during development in kale.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.285-294
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• 2011

Glucosinolate (GSL) contents were investigated (i) at 1~7 days after sowing (DAS) in seed sprouts and (ii) at 3-7 weeks after sowing for the time-course. Moreover, (iii) They were compared with five different cultivars of rocket salad (Eruca sativa). Seventeen GSLs were separated by HPLC analysis, and 10 GSLs among them were identified as glucoraphanin, sinigrin, glucoalyssin, diglucothiobeinin, glucobrassicanapin, glucoerucin, glucobrassicin, dimeric, 4-mercaptobutyl GSL, 4-methoxy glucobrassicin, gluconasturttin by using LC-APCI-MS analysis, but 7 compounds were not identified. (i) The total GSL content in seed sprouts initially increased up to 3 DAS and then decreased according to their seedling growth. In particular, glucoraphanin known as a strong anti-cancer reagent was found the highest level (5.05 ${\mu}mol/g$ dry wt.) at 3 DAS. The most abundant GSL was glucoerucin ranged from 26.0~49.6 ${\mu}mol/g$ dry wt. (ii) In the time-course, the total GSL contents increased dramatically from 3-week (5.91 ${\mu}mol/g$ dry wt.) to 7-week after sowing (32.2 ${\mu}mol/g$ dry wt.). The major GSLs were glucoraphanin, glucoerucin and 4-methoxy glucobrassicin. (iii) By comparing GSL contents with five different cultivars, the total GSL contents increased from 4-week to 6-week after sowing, regardless of cultivar. In 4-week-old, the order with the total GSL content was "Rucola" > "Rocket Herbs" ${\geqq}$ "Odyssey" > "Takii" > "Herb", but in 6-week-old it is changed as "Takii" > "Herb" > "Odyssey" > "Rucola" > "Rocket Herbs" even there was almost no significantly difference between them.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7309-7313
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• 2015

Background: The organ preservation approach of choice for the treatment of locally advanced head and neck cancers is concurrent chemoradiation with three weekly high doses of cisplatin. Although this is an efficacious treatment policy, it has high acute systemic and mucosal toxicities, which lead to frequent treatment breaks and increased overall treatment time. Hence, the current study was undertaken to evaluate the efficacy of concurrent chemoradiation using 40 mg/m2 weekly cisplatin. Materials and Methods: This is a single institutional retrospective study including the data of 266 locally advanced head and neck cancer patients who were treated with concurrent chemoradiation using 40 mg/m2 weekly cisplatin from January 2012 to January 2014. A p-value of < 0.05 was taken to be significant statistically for all purposes in the study. Results: The mean age of the study patients was 48.8 years. Some 36.1% of the patients had oral cavity primary tumors. The mean overall treatment time was 57.2 days. With a mean follow up of 15.2 months for all study patients and 17.5 months for survivors, 3 year local control, locoregional control and disease free survival were seen in 62.8%, 42.8% and 42.1% of the study patients. Primary tumor site, nodal stage of disease, AJCC stage of the disease and number of cycles of weekly cisplatin demonstrated statistically significant correlations with 3 year local control, locoregional control and disease free survival. Conclusions: Concurrent chemoradiotherapy with moderate dose weekly cisplatin is an efficacious treatment regime for locally advanced head and neck cancers with tolerable toxicity which can be used in developing countries with limited resources.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7331-7335
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• 2015

Background: Concurrent chemoradiation with three weekly high dose cisplatin is the non-surgical standard of care for the treatment of locally advanced head and neck cancers. Although this treatment regime is efficacious, it has high acute toxicity, which leads not only to increased treatment cost, but also to increased overall treatment time. Hence, the current study was undertaken to evaluate the acute toxicity and tumor response in head and neck cancer patients treated with concurrent chemoradiation using $40mg/m^2$ weekly cisplatin, which has been our institutional practice. Materials and Methods: This single institution retrospective study included data for 287 head and neck cancer patients treated with concurrent chemoradiation from 2012 to 2014. Results: The mean age of the patients was 48.8 years. The most common site of involvement was oral cavity. Most of the study patients presented with advanced stage disease. The mean overall treatment time was 56.9 days. Some 67.2% had overall complete response to treatment as documented till 90 days from the start of treatment. According to the Radiation Therapy Oncology Group (RTOG) acute radiation morbidity scoring criteria, mucositis was seen in 95.1% of the patients. Dermatitis and emesis were observed in 81.9% and 98.6%, respectively. Regarding haematological toxicity, 48.8% and 29.6% suffered from anaemia and leukopenia, respectively, during treatment. Acute kidney injury was assessed using the Common Terminology Criteria for Adverse Events (CTCAE), and was found in 18.8% of the patients. Conclusions: Concurrent chemoradiotherapy with weekly cisplatin is an effective treatment regime for head and neck cancers with reasonable toxicity which can be used in developing countries, where cost of treatment is so important.

• Korean Journal of Agricultural Science
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• v.42 no.3
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• pp.167-175
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• 2015

The present study aimed to investigate the effects of drought stress on the accumulation of glucosinolates (GSLs) in the leaves of Kale cultivated in autumn and spring. HPLC analysis guided to identify seven GSLs including progoitrin, glucoraphanin, sinigrin, gluconapin, glucobrassicin, 4-methoxyglucobrassicin and neoglucobrasscin. Quantification of GSLs revealed that the contents of sigirin was the highest (45%) followed by the level of progoitrin (24%) in terms of total GSLs. The ranges of total GSL contents was 1.16 (84)-15.88 (89 DAS, ${\mu}mol/g$ dry wt. (DW)) in treatment plot and 1.23 (84)-7.05 (74 DAS, ${\mu}mol/g$ dry wt.) in control plot showed the enhancement in the contents of GSLs in treatment than in the control plot. The present results evidenced that the variation of total GSL contents were depending on the harvest period. In 105 DAS, comparatively no differences in the GSL contents on each sample in autumn season, whereas in spring season, although there was decrease in the GSLs tendency from 74 DAS to 84 DAS in both control and treatment plot, the GSL contents of treatment plot was dramatically increased in 89 DAS. In treatment plot, the GSL contents on 89 DAS (1.16) was 15 fold higher to 84 DAS ($15.88{\mu}mol/g$ DW). The variation in the contents of GSL in spring and autumn did not documented significant differences because of their differences in the growth time and cultivation conditions. In conclusion, the GSL contents in kale was likely to be affected by drought stress treatment. Scrutiny and further research for exact relation between drought stress and GSL contents in kale should be needed.

• Food Science and Preservation
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• v.24 no.3
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• pp.367-373
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• 2017

This study examined the total glucosinolate (GSL) and isothiocyanate (ITC) contents according to different processing conditions; fresh Kimchi cabbage (Brassica rapa L. ssp. pekinensis), salted Kimchi cabbage and kimchi (storage temperature $4^{\circ}C$ and $20^{\circ}C$) using two different cultivars (Bomatnorang and Chunkwang). Four GSL peaks representing gluconapin, glucobrassicanapin, glucobrassicin and 4-methoxyglucobrassicin were detected in Kimchi cabbage by HPLC and HPLC/MS analysis. The total GSL contents of fresh Kimchi cabbage of Bomatnorang and Chunkwang were $21.37{\pm}1.06{\mu}g/g$ dry weight (DW) and $20.96{\pm}3.33{\mu}g/g$ DW, respectively. After salting, the total GSL contents of salted Kimchi cabbage decreased by 39% and 52% in Bomatnorang and Chunkwang, respectively. Finally, the total GSL contents of kimchi after storage at $20^{\circ}C$ decreased by 83% and 56% in Bomatnorang and Chunkwang, respectively. The extracted ITC contents were analyzed by GC/MS. Three ITC peaks were detected in Kimchi cabbage representing 2-phenylethyl ITC, 3-butenyl ITC and 4-pentenyl ITC. The 2-phenylethyl ITC levels increased during the salting process but this generally fell during storage at $20^{\circ}C$ as kimchi. The 3-butenyl ITC levels of Kimchi cabbage according to processing decreased rapidly due to salting and then decreased slowly during storage as kimchi. The 4-pentenyl ITC of Kimchi cabbage was lost during the salting process. The results for the change in GSL and ITC contents during the kimchi making process will be used in the food industry.

• Asia Pacific Journal of Corpus Research
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• v.1 no.1
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• pp.61-94
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• 2020

The present study examined vocabulary usage in elementary English classrooms in Japan using elementary school corpus. The authors used three wordlists to benchmark the lexical items for four classes in the corpus: the CEFR-J, the General Service List (GSL), and Academic Word List (AWL). The percentage of vocabulary usage belonging to the Level A1 in the CEFR-J was below 15% (Class A: 12.1%, Class B: 12.6%, Class C: 8.9%, and Class D: 13.6%) with no statistical difference between levels. The mean ratio of Level A2 vocabulary items was below 10%, and all classes showed less than 1% of vocabulary usage for the Levels B1 and B2. Over 70% of all vocabulary items in the corpus belonged to the most frequent 1,000-word band (level 1) of the GSL, while the next most frequent word band (level 2 of the GSL and AWL) accounted for less than 10%. The results suggest that elementary school English teachers should use more vocabulary items in the CEFR-J Level A1. The findings demonstrate that elementary school teachers are less likely to expose their pupils to grammatically well-structured sentences with an abundance of lexical items since the teachers repeatedly use the same lexemes in each class.

• Korean Journal of Agricultural Science
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• v.32 no.2
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• pp.205-214
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• 2005

The purpose of this study was to investigate the effect of ground corn as an additive to ginseng residue silages. The silages were made with corn (CS), red ginseng (GS), red ginseng residue +0.5% ground corn (GS0.5), w/w bases, red ginseng residue+1.0% ground corn (GS1.0) and red ginseng residue+silage inoculant, lactic acid bacteria (GSL). The raw materials were cut only for corn forage in 2cm length. The ginseng residue without cutting were mixed without or with additives, ground corn and inoculant, and ensiled each into two 2,000ml glass bottles. The bottles with silages were stored at a dark place at room temperature and formented for 60 days. The crude protein contents were higher for all red ginseng silages as 17.7, 18.8, 18.3 and 17.8% for GS, GS0.5, GS1.0 and GSL than that of corn silage as 8.8% (p<0.05). The calcium content were higher in GS, GS0.5, GS1.0 and GSL as 0.99, 1.13, 0.99 and 1.03% than that in CS as 0.31% (p<0.05). The pH of silages fermented for 60 days was similar each other; CS, GS, GS0.5, GS1.0 and GSL as 3.8, 3.7, 3.3, 3.5 and 3.7, respectively. However the pH of GS0.5 was the lower than that of corn silage. The total concentration of volatile fatty acids were higher for CS as 87.3 mM/dl than those of GS, GS0.5, GS1.0 and GSL as 44.7, 37.8, 46.3 and 47.2 nM/dl. However, the percentage of lactic acid concentration of ginseng silages such as GS, GS0.5, GS1.0 and GSL, 60.2, 77.2, 83.4 and 77.3% was higher than that in CS, 53.7% (p<0.05). The in vivo dry matter digestibilities for 72hr fermentation was higher in ginseng silages (GS, GS0.5, GS1.0 and GSL as 76.5, 75.8, 72.9 and 77.3%, respetively) than that in for CS as 52.1% (p<0.05). It can be concluded that silage added with ground corn (GS0.5 and GS1.0) and lactic acid inoculant were high in its quality, and the GS0.5 can be suggested as a practical method for red ginseng residues silage making.