고준위방사성폐기물처분을 위한 부지특성평가 기술을 구축하고, 이를 활용하여 심부지질환경을 이해하기 위해 1997년부터 지금까지 한국원자력연구원 주변 지역을 고준위폐기물처분을 위한 연구지역으로 선정하여 다양한 지질 관련 연구를 수행해왔다. 특히, 2002년에는 고준위폐기물의 처분 대상 심도의 시추공 (지하 500m)을 굴착하였으며, 2006년에는 지하처분연구시설 (KURT, KAERI Underground Research Tunnel)을 준공하여 연구지역에 대한 심부지질환경 규명을 위해 노력하고 있다. 현재, 지하처분연구터널의 좌측 연구용 모듈 내에 500 m 길이의 장심도 시추공 및 지하처분연구시설에서 남쪽으로 약 200 m 이격된 위치에서 1,000m의 장심도 시추공에서 다양한 부지특성평가 연구를 수행 중에 있다. 본 연구는 고준위폐기물의 심지층 처분을 위한 요소기술인 심부영역의 부지특성평가기술을 구축하기 위해 수행되었으며, 수리지질학적인 관점에서 부지특성평가의 기본 모델이 되는 3차원 지질모델을 구축한 내용이다. 연구지역에서 수행된 지표 지질조사와 시추공 자료를 이용하여 종합 분석한 결과, 수리지질학적 관점에서 중요한 풍화대, 상부 저경사단열대, 심부 영역에 존재하는 결정론적 단열대를 규명하여 3차원으로 모형화하였으며, 향후 본 연구를 통해 도출된 지질요소의 수리지질특성을 평가하여 고준위방사성폐기물처분 분야에 중요한 기술인 심부 영역의 수리지질환경을 이해하는데 활용될 예정이다.

A level of dietary iron may play a role in colon carcinogenesis. The effect of dietary iron on colon carcinogenesis was investigated in male ICR mice. Five-week old mice were acclimated for one week and fed on iron-normal diet (35 ppm Fe), iron-deficient diet (3 ppm), or iron-overloaded diet (350 ppm Fe) for 8 weeks. Animals received three (0-2^nd weeks after starting experiment) injections of azoxymethane (AOM; 10 mg/kg b.w.) to induce colonic aberrant crypt foci (ACF). There were five experimental groups including normal control without AOM, AOM+iron-normal diet (AOM+NFe), AOM+iron-deficient (AOM+LFe), AOM+ironoverloaded diet (AOM+HFe) groups. The total numbers of ACF and aberrant crypt (AC) were measured in the colonic mucosa after staining with methylene blue. The blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. The hepatic iron levels were significantly dependent on the presence of iron in the diets. Iron-deficient diet significantly decreased the several hematological values. The values of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvate transaminase (GPT) were also significantly decreased in iron-overloaded or iron-deficient diet groups, compared with normal iron diet group. Dietary iron-deficiency decreased the numbers of ACF (64.9) and AC (79.8) per colon by 20.6 and 21.8%, respectively, compared with AOM+NFe group (72.4 ACF/colon and 90.3 AC/colon). However, ironoverloaded diet increased ACF (82.9) and AC (96.0) induction by AOM, compared with normal iron diet. These results suggest that dietary iron can affect the colon carcinogenesis in the animal model of mice.

The Black Soldier Fly (BSF, Hermetia illucens) was widely distributed throughout Korea. This insect was mainly found in the vicinity of and in cattle sheds, manure sheds, living waste dump grounds, and food waste dump grounds. This fly is a kind of a beneficial fly because BSF adults do not go into houses, they do not regurgitate on human food, they do not bite, bother or pester humans in any way and they are not associated in any way with the transmission of disease. But their greatest attribute lies their ability to eat and digest raw waste. They can devour, for example, a large, raw, Irish potato and others in just a few hours. Unlike many other flies, since the BSF larvae have very powerful mouth parts and digestive enzymes, they can ingest raw waste far more efficiently than any other known species of fly. On this study, to investigate whether feeding strategy of the BSF larvae involves extra-oral digestion or not, and to better understand this process, the salivary glands and a few tissue from the BSF were dissected and subjected to morphological and preliminary enzyme characterization.

Varroa destructor is an ecto-parasite mite and worldwide pest of the honey bee Apis mellifera L. The pyrethroid tau-fluvalinate (Apistan), an acaricide that is tolerated by honey bees, has been used for varroa mite control since the mid 1980s. Even though various resistances to tau-fluvalinate in varroa mites have been reported from Europe, Israel, and USA, the nature of tau-fluvalinate resistance in varroa mites in Korea has never been investigated. To investigate and understand tau-fluvalinate resistance in varroa mites in Korea, we conducted bioassay in several apiaries located different regions in Korea. To understand the molecular mechanisms underlying the difference of tau-fluvalinate resistances in varroa mites, partial genomic DNA fragments of a voltage-sensitive sodium channel gene from varroa mites were cloned and sequenced, since tau-fluvalinate is known to act on the sodium channels directly. Two novel mutations in sodium channels of varroa mites were present in eight apiaries. Two mutations might be a geographical polymorphism of sodium channel of varroa mites in Korea.

This study was carried out to investigate effect of herbal extracts mixtures on hair growth in an alopecia model of C57BL/6 mice. There were 4 experimental groups including distilled water (DW, negative control), 25% ethanol(EtOH, vehicle control) and two herbal extract mixtures (HE-1 and HE-2). HE-1 included Polygonum and Brassica campestris extracts and HE-2 included Mulberry root and Gardenia extracts. The 6 weeks-old C57BL/6 male mice were shaved with an electric clipper and the test compounds were topically treated with 0.2 ml per mouse daily for 3 weeks. The hair re-growth was photographically determined at days 0, 4, 7, 10, 14, 17, and 21. The number of mast cells which is an important modulator of hair growth was counted in 1 cm of dorsal skin section of mice. There were no clinical signs in all experimental groups. As the results of photometric analysis, the topical application of the herbal extracts (HE-1 & 2) for 2 weeks to dorsal skin accelerated hair re-growth remarkably faster than that of DW group (p＜0.05). Activity of alkaline phosphatase (ALP) was significantly increased in EtOH group compared to DW group (p＜0.05). Both herbal extract mixtures also increased the ALP activity, but it was not significantly different from DW. Treatment of mice with HE-2 significantly increased mast cell population compared to EtOH. Taken together, these results suggest that herbal extract mixtures used in this study may have hair-growth promoting activities and can be useful for treatment for male pattern baldness or alopecia in humans.

The objective of this study was to determine the potential hazardous effects of sorting process by flowcytometry on the quality of boar spermatozoa by flowcytometer. Freshly collected boar semen was diluted and divided into two groups; control none sorted and sorted. Sperms in sorted group were processed with flowcytometer for cell sorting with 100 uM nozzle under the 20 psi pressure. Measurements on each parameter were made at two time points, 0hr (right after sorting) and 24 hr post sorting. Although there was a tendency of lower viability in sorted group than none sorted control group, the percentage of live cells in control(75.83+-6.92 & 59.53+-10.34) was not significantly different from sorted (59.7+-7.34 & 43.97+-3.76) at both 0 and 24 hr post sorting. However, sorted sperm showed significantly lower mitochondrial function compared to the control at both 0 h (79.37+-3.22 vs. 63.50+-10.05) and 24hr(67.27+-3.22 vs. 46.97+-5.37) time points (p<0.007). Sperm DNA fragmentation rate was significantly lower in control (22.0+-7.04) than that of sorted (32.27+-7.49) at 24 hr time point (p<0.0002). Taken together, these data suggested thatsorting process by flowcytometer may have influenced sperm motility rather than viability. Also high speed sperm sorting by flowcytometer has significant effects on DNA fragmentation on elapsed time after sorting.

Phytic acid (PA) is a naturallu occurring polyphosphorylated carbohydrate that is present in substantial amounts in almost all plants and mammalian cells. Recently PA has received much attention for its role in anticancer activity. We investigated the preventive effect of PA on the formation of colonic aberrant crypt foci (ACF), a preneoplastic lesion, induced by azoxymethane (AOM). After acclimation for one week, six-week old male ICR mice were fed on the AIN-93G purified diet and PA (0.5% or 2% PA in water) for 8 weeks. The animals were treated with azoxymethane (AOM, 10 mg/kg b.w.) three times (0, 1, and 2 weeks) to induce colonic aberrant crypt foci (ACF). After sacrifice, the total numbers of aberrant crypts (AC) and ACF in colonic mucosa were counted after staining with methylene blue. Blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. AOM treatment without PA induced the total numbers of 85.7 ± 12.9 and 115.2 ± 19.9, respectively. PA at the dose of 2% AC/colon by PA at the dose of 0.5% were 73.4 ± 12.9 and 115.2 ± 19.9, respectively. PA at the dose of 2% significantly decreased the ACF and AC numbers to 56.5 ± 14.6 and 95.4 ± 17.2, respectively (p＜0.01). PA at the doses of 0.5 and 2% decreased the numbers of ACF and AC/colon in a dose-dependent manner. Although some parameters in blood counts and serum chemistry were changed compared with the control, no specific toxicity was found. Theses findings suggest that phytic acid can be a chemopreventive agent for colon carcinogenesis resulting from inhibition of the development of ACF in ICR mice.

본 연구에서는 확산에 의해 발생하는 시멘트 방벽의 변질 과정을 반응성용질이동 모델링을 통해 장기간 동안 예측하고자 하였다. 모델링 결과 50,000년 후 시멘트의 변질은 30cm까지 진행되었다. pH는 13.0에서 11.86까지 감소하였으며 이는 알칼리 이온의 감소, 포틀랜다이트(portlandite)와 CSH (Calcium Silicale Hydrate)광물의 용해/침전반응에 의해 결정되고 있었다. 공극률 또한 portlandite와 의 용해에 의해 가장 큰 영향을 받고 있었으며 최고 약 0.3 점도 증가하였다. 우라늄의 용해도 역시 증가하고 있었으며 이는 pe의 증가에 기인하고 있었다. 본 연구 결과는 장기간의 시멘트 변질이 pH, pe, 공극률을 변화시킴으로서 핵종의 이동을 증가시킬 수 있음을 보여주고 있다.

본 연구에서는 핵폐기물 매립장의 인공 방벽으로 사용되는 시멘트 물질들과 주변 지하수 반응 결과로 형성되는 강알칼리성 지하수와 주변 암과의 반응을 통해 변화되는 지하수 특성을 지구화학 모델링을 통해 예측하고자 하였다. 연구 결과 시멘트 수화반응을 통해서 pH는 13.3를 나타내었으며 이때 생성되는 광물들은 Brucite, Katoite, Calcium Silicate Hydrate(CSH 1.1), Ettringite, Hematitie, Portlandite였다. 이들 광물들과 경주 지역에서 채취된 지하수의 반응 모델링에서는 지하수의 pH가 12.4로 예측되었다. 이러한 강알칼리성 지하수와 주변 화강암과의 반응은 년 동안 반응속도 모델링을 통해 모사하였다. 그 결과 지하수의 최종 pH는 11.2였으며 pH는 규산염 광물과 CSH 광물들의 용해 침전에 의해 조절되고 있었다. 또한 지하수 수질도 이들 광물들과 점토광물 및 산화광물들의 용해 침전에 의해 결정되고 있었다. 본 연구 결과는 장기간 동안의 강알칼리성 지하수와 주변 암과의 반응 모델링을 통해 지구화학 및 수질 변화를 예측함으로서 인공 방벽의 안정성 평가에 기여할 수 있을 것으로 판단된다.

본 연구에서는 고준위 방사성폐기물 심지층 처분시설의 규모 및 layout설정에 필요한 요소인 처분터널 및 처분공 간격에 대한 분석을 수행하였다. 이를 위하여, 기준 처분개념과 공학적 방벽 개념을 바탕으로 다양한 조건의 처분터널 및 처분공 단면을 설정하고, 단층 배치 및 복층 배치 개념 에 따른 처분동굴의 구조적, 열적 안정성을 분석하였다. 분석 결과를 바탕으로 설계에 있어서 주요한 고려인자 중의 하나인 굴착량을 감소시킬 수 있는 처분동굴 및 처분공 간격을 제안하였다. 본 연구의 결과는 심지층 처분시설 설계시 활용될 것이며, 향후, 부지에 대한 불확실성을 줄이기 위하여 정확한 부지특성 자료를 통한 상세한 분석이 필요하다.

μ방lt emitting diodes (LED) devices are commercially introduced as an alternative for low-Ievellaser therapy (11ι，T) ， and it has several advantages over lasers such as a safe, efficient, and less-expensive altemative to treat wounds. And LED irradiation at the same biostimulatory wavelength has similar bíochemical effεαs. In the present study, to asses whether the I핑ht-emitting diode (LED) irradíation can stimulate bone regeneration, irradiated bony defects with or without grafting materials on rat calvaria were compared to corresponding nonirradiated control. Fifty male Sprague-Dawly rats weighing about 150g, were used. Factors for present study were designed as follows, 1) presence or absence of grafting materials, 2) with or without irradiation, and 3) number of irradiation. Two weeks after operation, rats were sacrifìced. Radiologic and 비stomorphologic fmdings were evaluated. Macrospically, there were no incidents of infection, dehiscence, hematoma and necrosis during study. Radiological findings showed greater radiopacity in the graft group and radiopacity increased as the number of irradiation increase. And microscopically, new bαle formation was great in the graft group and increased as the number of irradiation increase, Present study has shown that LED irradiation improved bone regeneration through radiologic and histomorphologic fmdings in rat.