본 연구는 2009년 시범사업으로 시작된 대체교사 지원사업 제도를 진단하고 향후 방향을 모색하기 위한 기초연구로 3개시 어린이집 원장 221명, 교사 590명, 총 811명을 대상으로 원장과 교사의 배경별 대체교사 지원사업 이용여부, 대체교사 지원사업에 대한 원장과 교사의 인식, 대체교사 지원사업 이용 경험이 있는 원장과 교사의 인식, 대체교사 지원사업을 이용해보지 않은 원장과 교사의 대체교사 지원사업 이용 실태와 인식을 조사하였다. 연구결과, 원장과 특히 교사를 대상으로 대체교사 지원사업에 대한 적극적 안내가 필요하며, 대체교사 지원 수요에 비하여 대체교사 지원이 부족한 것으로 나타나 대체교사 인력확충이 필요한 것으로 판단된다. 또한 보육교사의 자유로운 연차사용 환경조성과 이에 대한 사회적 인식의 변화와 제도적 뒷받침이 필요함을 알 수 있다.

In this study, a series of studies is intended to elicit the improvement of the quality of Admixture Substitute Concrete using oil refined for petrochemical work (ERCO). In other words, ERCO is used to analyze the basic properties of Admixture Substitute Concrete by pre-adding the AE liquid solution on its products. As an experimental variable, the method of adding ERCO was added after mixing it with concrete. In addition, the mixing ratio was planned to be 2 levels of 0, 0.5 %, and the total volume of the AEs injection quantity is 5 % that combines 0, 1, 2, and 3 % of the mixed ERCO mass of concrete. As a result, as the pre-injection of AE was increased, the characteristics of the concrete showed that the slump, and air contents were not improved, and the pre-adopting effects of AE agent were also significantly increased in the concrete.

In the present study, we employed Hershberger assay to determine possible androgenic or antiandrogenic activities of three di-2-ethylhexyl phthalate (DEHP) substitute candidates. The assay was carried out using immature castrated Sprague–Dawley male rats. After 7 days of the surgery, testosterone propionate (TP, 0.4 mg/kg/day) and test materials (low dose, 40 mg/kg/day; high dose, 400 mg/kg/day) were administered for 10 consecutive days by subcutaneous (s.c.) injection and oral gavage, respectively. Test materials were DEHP, 2-ethylhexyl oleate (IOO), 2-ethylhexyl stearate (IOS) and triethyl 2-acetylcitrate (ATEC). The rats were necropsied, and then the weights of five androgen-dependent tissues [ventral prostate, seminal vesicle, coagulating glands, levator ani-bulbocavernosus (LABC) muscle, paired Cowper’s glands, and glans penis] and four androgen-insensitive tissues (kidney, adrenal glands, spleen and liver) were measured. All test materials including DEHP did not exhibit any androgenic activity in the assay. On the contrary, antiandrogen-like activities were found in all test groups, and the order of the intensity was ATEC < DEHP < ISO < IOO in the five androgen-sensitive tissues. There was no statistical difference between low dose treatment and high dose treatment of all replacement candidate groups. In DEHP groups, high dose treatment exhibited significant weight gains in LABC and Glan Penis. There was no statistical difference in androgen-insensitive tissue measurements. Since the effects of ATEC treatment on the accessory sex organs were much less or not present at all when compared to those of DEHP, ATEC could be a strong candidate to replace DEHP. IOO treatment brought most severe weight reduction in all of androgen-sensitive tissues, so this material should be excluded for further screening of DEHP substitute selection.

Bisphenol-A(BPA) is a member of alkylphenol family, and shows adverse effects including reduced fertility, reproductive tract abnormalities, metabolic disorder, cancer induction, neurotoxicity and immunotoxicity. In the present study, we conducted Hershberger assay to evaluate whether the two candidates to replace BPA have androgenic or antiandrogenic activity. The assay was carried out using immature castrated Sprague–Dawley male rats. After 7 days of the surgery, testosterone propionate (TP, 0.4 mg/kg/day) and test materials (low dose, 40 mg/kg/day; high dose, 400 mg/kg/day) were administered for 10 consecutive days by subcutaneous (s.c.) injection and oral gavage, respectively. Test materials were BPA, isosorbide (ISO) and cyclohexanedimethanol (CHDM). The rats were necropsied, and then the weights of five androgen-dependent tissues [ventral prostate, seminal vesicle, levator ani-bulbocavernosus (LABC) muscle, paired Cowper’s glands, and glans penis] and three androgen-insensitive tissues (kidney, spleen and liver) were measured. All test materials including BPA did not exhibit any androgenic activity in the assay. On the contrary, antiandrogen-like activities were found in all test groups, and the order of the intensity was CHDM > BPA > ISO in the five androgen-sensitive tissues. There was no statistical difference between low dose treatment and high dose treatment of BPA group as well as ISO group. In CHDM group, high dose treatment exhibited most severe weight reduction in all measured tissues. There was no statistical difference in androgen-insensitive tissue measurements, except BPA groups. Since the effects of ISO treatment on the accessory sex organs were much less or not present at all when compared to those of BPA, ISO could be a strong candidate to replace BPA. CHDM treatment brought most severe weight reduction in all of androgen-sensitive tissues, so this material should be excluded for further screening of BPA substitute selection.

The purpose of this study was to determine the feasibility of using waste stone and waste stone sludge, generated by stone grinding operations, as substitutes for natural resources. In addition, the possibility of expanding the scope of safe recycling was confirmed via an environmental assessment. This assessment was carried out by measuring particle size distributions and physical and chemical characteristics, as well as via dissolution and content tests. Waste stones and powdered waste stone sludge generated from the I-, K-, and R-quarries located in the Geochang area were selected and sampled. The pH was weakly alkaline (7.74 - 9.7), and the water content ranged from 21.29% to 32.57%. Only the Iquarry sample exceeded the 30% water content limit. The Waste Control Act regulates the use of filler materials such as bottom restoration and lowland materials in the quarry to less than 30%. Leaching tests conducted using I-, K-, and R-quarry samples were analyzed. The samples did not exceed the controlled waste criteria for hazardous substances defined by the Waste Management Act. The limits for Pb, Cr, As, Hg, Cd, and Cr6+ are 3 mg/L, 3 mg/L, 1.5 mg/L, 0.005 mg/L, 0.3 mg/L, and 1.5 mg/L, respectively. Based on the results of content tests, only Cu (252 mg/Kg) exceeded the 1 area standard (150 mg/kg) for troublesome soil contamination defined in the Enforcement Regulations of the Soil Environment Conservation Act. Based on this environmental assessment, current policies allow expansion of recycling.

This study was carried out to know the substitute effect of Yacto (leaf mold compost) on popped rice hulls compost (PRHC) in Yang-jik nursery bed of Panax ginseng. PRHC was mixed with Yacto as 50:50 ratio, and 1 ~ 2% of the mixed oil cake, rice bran and urea were also added to promote decaying the mixed compost. The mixed compost made by PRHC and Yacto was showed that positive effect on the growth of ginseng seedling when it was mixed with 1% of oil cake and rice bran, and 2% of mixed oil cake. But addition to the 2% of urea in the mixture of PRHC and Yacto was not positive effect on the growth of ginseng seedling. Root yield of the mixed compost was similar to that of conventional compost by made 100% of Yacto. Therefore, the mixed compost can substitute for Yacto when PRHC and Yacto were mixed by 50:50 ratio and added 1% of oil cake and rice bran.

This study was carried out to select economical byproduct composts as the substitute for the traditionalorganic fertilizer, Yacto, in the cultivation of ginseng seedlings, and to investigate the application method of a selected com-post. Among tested byproduct composts, popped rice hull compost was the best substitute for Yacto, while the application ofdomestic animal manure composts resulted in red skinned roots of ginseng seedlings. Optimal mixing ratio of the poppedrice hull compost with virgin soil (fine sand) were 3~4:1 in bulk, showing the same root yield compared to that of conven-tional seedbed soil. When the popped rice hull compost was lower than 1±0.1% in nitrogen content, the expeller cake of oilseed was added to seedbed soil to rise nitrogen content until 1±0.1%.

중간엽 줄기세포(MSC)를 체외배양할 때 사용하는 소태아혈청 (FBS)의 생물학적 불안전성은 이를 임상적으로 사용하는데 있어 제한점으로 작용한다. 본 연구에서는 소태아혈청 및 인간의 제대혈청을 사용하여 인간의 양막유래 중간엽 줄기세포 (HAM)를 각각 배양한 후, 세포의 성장속도와 유전자 및 단백질의 발현 양상을 비교하였다. 제왕절개 후 얻은 양막으로부터 HAM을 분리하여 10% FBS, 5% HCS 혹은 10% HCS가 각각 첨가된 DMEM 배양액에서