Background: The successful production of superior or transgenic offspring from in vitro produced embryos in cattle relies heavily on the quality of blastocyst stage embryos. In order to enhance the developmental competency of these embryos, a novel culture method was devised. Methods: This study utilized stem cell culture medium (SCM) from hESCs as a supplement within the culture medium for bovine in vitro produced embryos. To gauge the efficacy of this approach, in vitro fertilized embryos were subjected to culture in CR1aa medium enriched with one of three supplements: 0.3% BSA, 10% FBS, or 10% SCM. Results: The blastocyst development and hatching rates of one-cell zygotes cultured in CR1aa medium supplemented with SCM (23.9% and 10.2%) surpassed those cultured in CR1aa medium supplemented with BSA (9.3% and 0.0%) or FBS (3.1% and 0.0%) (p < 0.05). Furthermore, post-zygotic gene activation, cleaved embryos cultured in CR1aa medium supplemented with SCM (57.8% and 34.5%) exhibited notably higher rates (p < 0.05) compared to those cultured with BSA (12.9% and 0.0%) or FBS (45.7% and 22.5%) supplementation. Furthermore, the microinjection of SCM into the cytoplasm or pronucleus of fertilized zygotes resulted in elevated blastocyst development and hatching rates, particularly when the microinjected embryos were subsequently cultured in CR1aa medium supplemented with SCM from the 8-cell embryo stage onwards (p < 0.05), in contrast to those cultured with FBS supplementation. Conclusions: In conclusion, this study conclusively demonstrated that the incorporation of SCM into the culture medium significantly enhances the developmental progress of preimplantation embryos.
It has been claimed that artificial insemination (AI) of cows with frozen-thawed semen treated with commercially produced kits, Wholemom (in favour of female gender) increases the birth chance of calves with desired sex ratio by approximately 85% without decrease of pregnancy rates. Hence, this study was conducted to investigate the efficacy of wholemom kits as combined with frozen-thawed bovine semen during in vitro fertilization on the in vitro fertilization and developmental efficiency and sex ratios such as some reproductive parameters in bovine. For this, 1,737 oocytes were in vitro fertilized and developed. Agglutination effects on bovine after treatment of Wholemom kit were observed by time passage and dose respectively. To determine sex of embryos, Bovine embryo Y-specific gene primers(ConEY) and Bovine specific universal primer(ConBV) were used as multiple PCR method. Fertilization rate of wholemom-treated group was significantly lower than its of control group[66.9% (1,156/1,737) in Wholemom-treated group; 75.0% (610/813) in control group]. However, developmental rate after fertilization of both wholemom-treated and control groups were not significantly different [26.1% (404/1,156) in Wholemom-treated group; 27.4% (224/610) in control group]. Sex ratio of in vitro fertilized embryo with frozen-thawed semen treated with wholemom kit was determined by multi PCR. Female ratio in wholemom-treated group [85.4% (173/201)] was significantly higher than its of control group [47.2% (66/141)]. In conclusion, wholemom treatments of semen used in the in vitro fertilization and development of bovine oocytes provided increase in female ratio with decrease of fertilization rate.
Green mold of Phellinus baumii caused by Penicillium was observed in Daegu on August, 2000. The causal fungus was identified as Penicillium citrinum based on their cultural and morphological characteristics. Conidiophores one-stage branched, terminating in a whorl of 3~5 metulae. Metulae mostly 5.2~7.8㎛. Phialides were flask-shaped, 5.7~7.5×2.2~2.7㎛. Conidia were subglobose, 1.8~2.3㎛ in size. Colonies on Czapek agar were mostly attaining a diameter of 23 ㎜ within 8 days at 25 . The optimum temperature for growth of the fungus was about 20~30℃. On the basis of mycological characteristics and pathogenecity test on host mushrooms, the fungus was identified as Penicillium citrinum. This is the first report on the green mold of Phellinus baumii caused by Penicillium citrinum in Korea. The present study was carried out to investigate the preventive effect of Penicillium citrinum by backfill (sand, granite soil, and smash rock). The result showed that the use of granite was 3~10% infection rate and sand was 2~10% infection of P. citrinum. However, the smash rocks showed no infection of this fungus. The chemical properties of smash rocks was pH 8.4, showing alkalinity. The sand and granite soil were pH 6.1 and pH 7.5, respectively. These did not have heavy metals such as Mn, Fe, Pb and As.
Green mold of Phellinus baumii caused by Penicillium was observed in Daegu on August, 2000. The causal fungus was identified as Penicillium citrinum based on their cultural and morphological characteristics. Conidiophores one-stage branched, terminating in a whorl of 3~5 metulae. Metulae mostly 5.2~7.8㎛. Phialides were flask-shaped, 5.7~7.5×2.2~2.7㎛. Conidia were subglobose, 1.8~2.3㎛ in size. Colonies on Czapek agar were mostly attaining a diameter of 23㎜ within 8 days at 25℃. The optimum temperature for growth of the fungus was about 20~30℃. On the basis of mycological characteristics and pathogenecity test on host mushrooms, the fungus was identified as Penicillium citrinum. This is the first report on the green mold of Phellinus baumii caused by Penicillium citrinum in Korea. The present study was carried out to investigate the preventive effect of Penicillium citrinum by backfill (sand, granite soil, and smash rock). The result showed that the use of granite was 3~10% infection rate and sand was 2~10% infection of P. citrinum. However, the smash rocks showed no infection of this fungus. The chemical properties of smash rocks was pH 8.4, showing alkalinity. The sand and granite soil were pH 6.1 and pH 7.5, respectively. These did not have heavy metals such as Mn, Fe, Pb and As.
Fe-doped TiO2 nanopowders were prepared by mechanical alloying (MA) varying Fe contents up to 8.0 wt.%. The UV-vis absorption showed that the UV absorption for the Fe-doped powder shifted to a longer wavelength (red shift). The absorption threshold depends on the concentration of nano-size Fe dopant. As the Fe concentration increased up to 4 wt.%, the UV-vis absorption and the magnetization were increased. The benefical effect of Fe doping for photocatalysis and ferromagnetism had the critical dopant concentration of 4 wt.%. Based on the UV absorption and magnetization, the dopant level is localized to the valence band of TiO2.
[ ] 펠릿 20 kg HM/batch용 분말화 장치는 차세대관리 공정의 금속전환로 안으로 균질화된 분말을 공급하기 위하여 펠릿을 산화하여 으로 분말화하는 장치이다. 본 연구에는 펠릿 20 kg HM/batch용 분말화 장치 설계모델을 제시하고, 실증용 분말화 장치를 제작하여 검증실험을 수행한다. 분말화 장치 설계모델은 내부구조, 성능, 가열로 위치와 크기 등이 고려된다. 실험 방법은 펠릿 20 kg HM/batch용 분말화 장치 설계 모델에 따라 기존의 3단 메시 분말화 장치를 이용하여 분말의 메시 투과시험과 온도변화 특성 실험을 하여 장치 내부구조를 결정한다. 펠릿 20 kg HM/batch의 산화 반응도 실험과 가열로 위치별 온도 분포를 측정하고 장치의 성능과 가열로의 영 역 위치를 결정한다. 장치 크기를 결정하기 위하여 산화전의 20kg의 펠릿과 산화후의 부피를 측정한다. 이상의 결과를 토대로 실증용 분말화 장치를 설계. 제작하고, 검증을 위하여 산화도, 분말특성 및 분석 등을 수행하였다. 산화반응 실험결과 에서 기존장치에 비하여 분말의 메시 투과율이 향상되었으며, 기존의 3단 메시 장치의 펠릿산화시간이 13시간 소요된 것에 비하여 8시간으로 단축되었다. 분말 특성 분석결과, 평균 입도가 이었다. 제작된 펠릿 20 kg HM/batch용 분말화 장치 성능과 설계모델 예측 값은 대체로 잘 일치되었다.