For application in nuclear decommissioning, underwater laser cutting studies were conducted on thick stainless-steel plates for various cutting directions using a 6 kW fiber laser. For cutting along the horizontal direction with horizontal laser irradiation, the maximum cutting speed was 110 mm∙min−1 for a 48 mm thick stainless-steel plate. For cutting along the vertical direction with horizontal laser irradiation, a maximum speed of 120 mm∙min−1 was obtained for the same thickness, which confirmed that the cutting performance was similar but slightly better. Moreover, when cutting with vertically downward laser irradiation, the maximum cutting speed was 120 mm∙min−1 for a plate of the same thickness. Thus, the cutting performance for vertical irradiation was nearly identical to that for horizontal irradiation. In conclusion, it was possible to cut thick stainless-steel plates regardless of the laser irradiation and cutting directions, although the assist gas rose up due to buoyancy. These observations are expected to benefit laser cutting procedures during the actual dismantling of nuclear facilities.

The present study is designed to investigate the hypolipidemic effect of the hot-water extract from the leaves of Dendropanax morbifera L. (DMWE) in hyperlipidemic rats. Thirty male 5-week-old rats were grouped as follows: Normal control (NC) given distilled water; hyperlipidemic control (HC) administered with distilled water; drug treatment (DT) orally administered with atorvastatin (10 mg/kg body weight (BW)); DMWE-treated groups (DM-50, DM-100 and DM-200) treated with DMWE 50, 100 and 200 mg/kg BW, respectively. All groups (except for NC) were fed a high-fat diet during the experiment. After 4 weeks of administration, the BW of all groups treated with DMWEs significantly increased compared to that of HC (p<0.05) and showed no significant difference compared to that of NC. In addition, serum total cholesterol levels in all groups treated with DMWEs were meaningfully decreased, compared to that in HC (p<0.05). In serum triglyceride (TG) and low-density lipoprotein-cholesterol levels, both DM-100 and DM-200 considerably decreased compared to HC (p<0.05), and no significant differences in TG levels were between DM-100 and DM-200. In high-density lipoprotein-cholesterol levels, DM-200 was statistically different compared to HC, and there were no significant differences between DM-100, DM-200 and DT. Furthermore, aspartate transaminase and alanine aminotransferase concentrations of DM-100 and DM-200 were significantly decreased compared to those of HC (p<0.05). From results portrayed above, DMWE at the concentration of 100 mg/kg BW has been identified to be effective in the treatment of hyperlipidemic rats.

With the aim of developing region specialized crops, this study was conducted to clarify effects of variant and cultivation region on antioxidative activities in various black soybean (Glycine max L.) seed tissues. Three black soybean varieties (SCEL-1, Wonheug, and Cheongja 3) were each cultivated in 4 different regions (Jeonju, Pyeongchang, Paju, and Cheonan). Harvested seeds were used to assess DPPH and ABTS radical scavenging activity, and total polyphenol, flavonoid and anthocyanin content. SCEL-1 soybean hull contained higher DPPH and ABTS radical scavenging activity (61% and 85% respectively) compared to Wonheug (40% and 50% respectively). SCEL-1 cultivated in Pyeongchang displayed the highest total polyphenol and flavonoid content (1,189 mg GAE/ 100g sample and 951 mg CTE/ 100g sample, respectively). Total anthocyanin content was ranked in the following order: SCEL-1>Wonheug>Cheongja 3. All black soybeans showed much higher antioxidant activity in the soybean hull than in the dehulled soybean. The antioxidant activity of black soybeans cultivated at high latitudes was high. These results suggest that the best black soybean variant for high beneficial biological activities is the SCEL-1 variant. For a complete understanding of the potential of black soybean as functional foods, we plan to further analyze their antioxidant activities in future studies.

본 연구는 국내 자생하는 진달래속(Rhododendron) 종들의 종자 휴면유형 분류 및 발아특성 구명을 목표로 하였다. 진달래속 종들의 배는 형태적휴면(MD)이 없는 완전히 발달된 직선(linear) 형태였으며, 만병초 및 꼬리진달래 종자는 탈리 시점에 이미 휴면이 없는 것으로 밝혀졌다. 반면에 털진달래 종자는 population 수준에서 부분적으로 생리적휴면(PD)을 가지고 있는 것으로 나타났다. 털진달래의 이러한 생리적휴면 (PD)은 외생 지베렐린(GA3) 1,000mg･L-1 처리를 통해 타파될 수 있었다. 그러나 4℃에서의 저온층적처리는 털진달래 종자 휴면 타파에 효과가 없는 것으로 나타났다. 종합적으로 판단 했을 때, 진달래속(Rhododendron) 종들의 적정 발아 환경조 건은 광조건･25/15℃(만병초), 암조건･20/10℃(꼬리진달래), 광 조건･25/15℃(털진달래)로 확인된다. 진달래속(Rhododendron) 에서의 종간 차이(interspecific variation)로 인해 모든 종이 종자 휴면유형 또는 발아특성에서 구별이 되었다. 본 연구는 국내 자생하는 진달래속(Rhododendron) 종들의 생리･생태 특성을 이해하는 데 이용될 수 있을 것이다.

Under the stressed condition, a complex feedback mechanism for stress is activated to maintain homeostasis of the body and secretes several stress hormones. But these stress hormones impair synthesis and secretion of the reproductive hormones, followed by suppression of ovarian function. Cytochrome P450 1A2 (CYP1A2) plays a major role in metabolizing exogenous substances and endogenous hormones, and its expression is recently identified at not only the liver but also several organs with respect to the pancreas, lung and ovary. Although the expression of CYP1A2 can be also affected by several factors, understanding for the changed pattern of the ovarian CYP1A2 expression upon stress induction is still limited. Therefore, CYP1A2 expression in the ovaries from immobilization stress-induced rats were assessed in the present study. The stress-induced rats in the present study exhibited the physiological changes in terms of increased stress hormone level and decreased body weight gains. Under immunohistological observation, the ovarian CYP1A2 expression in both control and the stressed ovary was localized in the antral to pre-ovulatory follicles. However, its expression level was significantly (p < 0.01) higher in the stress-induced group than control group. In addition, stress-induced group presented more abundant CYP1A2-positive follicles (%) than control group. Since expression of the ovarian CYP1A2 was highly related with follicle atresia, increased expression of CYP1A2 in the stressed ovary might be associated with changes of the ovarian follicular dynamics due to stress induction. We hope that these findings have important implications in the fields of the reproductive biology.

Cytochrome P450 1A2 (CYP1A2) is a member of the cytochrome P450 superfamily enzymes in mammals and plays a major role in metabolizing endogenous hormones in the liver. In recent days, CYP1A2 expression has been found in not only the liver but also other tissues including the pancreas and lung. However, little information is available regarding the expression of CYP1A2 in the ovary, in spite of the facts that the ovarian follicle growth and atresia are tightly associated with controls of endocrine hormonal networks. Therefore, the expression of CYP1A2 in the ovaries of prepubertal and pubertal rats was investigated to assess its expression pattern and puberty-related alteration. It was demonstrated that the expression level of CYP1A2 was significantly (p < 0.01) higher in the pubertal ovaries than prepubertal counterparts. At the ovarian follicle level in both groups, whereas CYP1A2 expression was less detectable in the primordial, primary and secondary follicles, the strongly positive expression of CYP1A2 was localized in the granulosa cell layers in the antral and pre-ovulatory follicles. However, the ratio of CYP1A2-positive ovarian follicle was significantly (p < 0.01) higher in the ovary of pubertal group (73.1 ± 3.1%) than prepubertal one (41.0 ± 10.5%). During the Immunofluorescence, expression of CYP1A2 was mainly localized in Fas-positive follicles, indicating the atretic follicles. In conclusion, these results suggested that CYP1A2 expression was mainly localized at the atretic follicular cells and affected by the onset of puberty. Further study is still necessary but we hypothesize that CYP1A2 expresses in the atretic follicles to metabolize residue of the reproductive hormones. These findings may have important implications for the fields of reproductive biology of animals.

Buckwheat (Fagopyrum species) has long been an excellent functional food. Besides, buckwheat sprouts contain various functional substances. In this study, we investigated the antioxidant activity of buckwheat sprouts in the context of cultivars harvested after different cultivation periods (0, 3, 5, 7, 9, 13, and 15 days after planting). Buckwheat sprouts were cultivated at 25oC for up to 15 days and then extracted with ethanol. Antioxidant components were then extracted from sprouts and leaves using a freeze dryer. The total polyphenolic content, flavonoid content, and antioxidant activity were then analyzed. The total polyphenol content increased from 32.26 mg GA eq/100 g for raw buckwheat to 114.75 mg GA eq/100 g after 7 days of cultivation. Also, the flavonoid content increased from 20.61 mg catechin eq/100 g (0 days) to 56.54 mg/g after 9 days of cultivation. The DPPH radical scavenging activity (concentration of extract at 0.25 mg/mL) increased from 7.89% at day 0 to 53.48% after 9 days of cultivation. Additionally, the ABTS radical scavenging activity increased from 10.26% at day 0 to 32.89% after 7 days of cultivation; of note, the activity decreased afterward. These results suggest that the best buckwheat sprouts with higher biological activities are those cultivated for 7-9 days. For a complete understanding of the potential of buckwheat sprouts as functional foods, we plan to further analyze their antioxidant activity in the future.

목적 : 노안을 대상으로 멀티포컬 콘택트렌즈의 디자인에 따라 처방법을 다르게 하고 각각의 처방에 따른 시기 능을 비교하였다. 방법 : CNMF(center near multifocal) 콘택트렌즈를 성공적으로 착용하고 있는 초기노안 19명(남 3명, 여 16명, 평균연령 45.47±5.88세)을 대상으로 CDMF(center distance multifocal) 콘택트렌즈와 MMV(modified monovision) 콘택트렌즈를 각각 착용하도록 하고 처방법에 따라 시기능을 비교하였다. 시력검사는 ETDRS 시표 를 사용하여 측정하였고, 근거리 입체시력은 Stereo Fly Test를 이용하였으며, 시력 만족도는 NEI-VFQ-25 설 문지를 변형하여 측정하였다. 결과 : 처방법들에 따른 원거리 교정시력, 근거리 교정시력 및 입체시력은 차이가 없었다. 그러나 원거리 시력 만족도에 대한 설문조사에서는 야외광고를 볼 때와 낮에 운전을 할 때에는 CNMF, CDMF 착용 시 MMV보다 높 았고, 밤 운전 시에는 CDMF 착용 시에 가장 높았다(p<0.050). 중간거리 시력 만족도는 컴퓨터를 사용할 때와 밤에 계단을 오르내릴 때에는 CDMF와 MMV이 CNMF보다 높았다(p<0.050). 근거리 시력만족도는 신문 및 영수증을 볼 때에는 MMV이 CNMF, CDMF보다 높았으며, 전반적인 근거리 시력 만족도는 MMV 착용 시 높았다(p<0.050). 결론 : 세 가지 노안 교정법에 따라 시력은 차이가 없었지만 일상생활에서 시력 만족도는 주시거리와 환경에 따라 차이가 발생한다. 그러므로 착용자의 요구조건에 맞는 처방법을 선택한다면 멀티포컬 콘택트렌즈 착용 만족 도를 높일 수 있을 것으로 생각된다.

Globally, colon cancer is increased gradually and known as one of the major causes of cancer death. Stevia, a substitute of sugar, is known to have many components including alpha-tocopherol and anthocyanin etc, as antioxidants. This study's purpose is to investigate whether stevia plant extract can have a protective effect against colon carcinogenesis induced by azoxymethane (AOM) and dextran sodium sulfate (DSS) in mice. Total 30 male ICR mice were divided into 2 groups; AOM/DSS treatment (control group), AOM/DSS + stevia extract (0.5%, in drinking water). After acclimation for 1 week, five weeks old mice received three intraperitoneal AOM (10 mg/kg b.w.) injections weekly for 3 weeks (0–2nd weeks of the experiment) and 2% DSS as drinking water for the next one week. AIN-76A purified rodent diet and 0.5% stevia extract water were supplied to the animals for 6 weeks. The colons of mice were collected and the number of aberrant crypt foci (ACF) and aberrant crypts (ACs) in colonic mucosa were counted after staining with methylene blue. Malondialdehyde (MDA) concentration in feces were determined. The numbers of ACF and ACs were significantly (p<0.01) decreased in stevia-treated group compared with the control group. The MDA concentration in feces was also significantly (p<0.01) decreased in stevia-treated group compared with the control group. In histopathology of colonic epithelium, hyperplasia of colonic epithelium was less observed in steviatreated group. These results indicate that stevia has a protective effect against colon carcinogenesis induced by AOM/DSS in mice and further study needs to illustrate the protective mechanisms.