• 한국작물학회지
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• 제24권4호
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• pp.1-11
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• 1979

질소 및 인산시용이 수도의 지상, 지하부 생육에 미치는 영향을 검토하고 산소전극으로 측정한 근호흡과 지상, 지하부 생육과의 관련성을 알기 위하여 1978년 인공기상실에서 pot 실험을 수행하였으며 얻어진 결과를 요약하면 다음과 같다. 1. 질산시용량 증가에 따라 근호흡 및 지상부중은 증가되나 근중은 감소되었다. 2. 인산의 시용은 인산과 동량의 질소병용하에서만 근호흡을 증가시켰으며 근중 및 지상부중은 인산적량시비시에 증가되었다. 3. 저온하에서는 근호흡에 미치는 인산시비효과가 크지 않았으며 인산만의 단독증비는 근호흡을 크게 감소시켰다. 4. 근호흡은 근중과는 부의 상관을, 그리고 지상부중 및 양분흡수와의 정의 상관을 보였으며 단위면적당호흡 의미가 없고 단위근중당호흡만이 유효하였다. 5. 원연교잡종인 수원 258호는 일본형 품종인 진흥보다 저온에서의 인산반응이 낮은 경향이었다.

• 한국초지조사료학회지
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• 제14권1호
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• pp.1-6
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• 1994

This experiment was carried out to study the effect of cutting frequencies(2, 3: one time grazed after 2 cuts, 3, 4, 6 cuts per year) and nitrogen fertilization(0 and 120 kg per ha and year) on botanical composition of permanent grassland at the "Federal Research Institute for Agriculture in Alpine Regions(Gumpenstein)," Austria The results are summarized as follows: 1. With only fertilizing phosphorus(P) and potassium(K),mean annual dry matter yields were 6.9 - 8.4 ton per ha and highest when only one time grazed after 2 cuts, but fell progressively with increase in cutting frequency and additonal fertilization of nitrogen. The average nitrogen efficiences expensed as dry matter yieldsfig) per feltilized nitrogenfig per ha) were 10.3 kg. 2. When N fertilizer was applied, the proportion of tall and medium grasses in the mixed swards increased by 30 - 50% compared with only fertilizing PK. Whereas swards with fertilizing only PK generally stimulated composition of the legumes at the expense of the grasses(30 - 50%). 3. Although the proportion of tall and medium grasses(Trisetum flavescens and Dachlis glomerara) and tall herbs(hntodon hispidus, Taraxacum oflcinale and Aegopodium podagraria) increased by infrequent cutting, frequently cutting plots helped increase the proportion of short grasses(Poa pratensis and Poa trivialis), especially where plots both had been applied with nitrogen fertilizer. 4. Nitrogen fertilization resulted in higher existence of herbs and weeds such as Taramcum oficinale. Aegopodium podagraria, Galium mllugo, Anthriscus silvestris and Lamium album. 5. Due to unusually high or low cutting frequencies such as 4 cuts or 2 cuts per year increased botanical compostion of Heracleum sphondylium.hondylium.

• 원예과학기술지
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• 제33권1호
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• pp.24-30
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• 2015

분화 노루귀(Hepatica asiatica Nakai)의 적정광도 및 분용토, 그리고 시비수준을 알아보기 위해 플라스틱 하우스안에서 실험을 수행하였다. 차광망을 이용하여 자연광을 52, 82, 90, 97%로 차광을 하고 노루귀를 재배하였다. 차광율이 낮은 처리구(52%)에서는 생존율이 65%로 낮고, 차광율이 높아질수록 생존율도 높아져 90% 이상의 차광하에서는 생존율이 80% 이상이었다. 생체중이나 엽수와 같은 생육지표에서는 처리간 유의적인 차이가 보이지 않았다. 적정 분용토 선발 실험에서는 마사토:유비상토:녹소토(60:10:30, v/v/v)와 강모래:유비상토:바크(50:20:30, v/v/v) 혼합토에서 85% 이상으로 생존율이 높았으며, 강모래:유비상토:녹소토(50:30:20, v/v/v)와 밝흙:강모래(40:60, v/v) 배합토에서는 생존율이 60% 이하로 낮았다. 엽수와 초장에서도 마사토:유비상토:녹소토(60:10:30, v/v/v)에서 가장 좋았다. 적정 시비수준을 찾기 위해 Hyponex 액비를 1,000배 또는 2,000배로 희석하여 1회/1주, 또는 1회/2주로 처리했다. 생존율이 현저하게 떨어졌던 처리구는 1,000배 희석액을 주 1회 관주처리했을 때이었고, 다른 처리구에서는 처리간 유의적인 차이가 보이지 않았다. 결론적으로 노루귀는 매우 낮은 광도에서도 살아남을 수 있는 내음성이 매우 뛰어난 식물이며, 배양토로는 배수성과 통기성이 좋은 용토를 선호하고, 상당히 폭넓은 시비수준에 적응할 수 있는 식물이라고 생각되었다.

• Clinical and Experimental Reproductive Medicine
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• 제46권4호
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• pp.189-196
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• 2019

Objective: We aimed to evaluate the effects of different oxygen conditions (20% [high O₂], 5% [low O₂] and 5% decreased to 2% [dynamic O₂]) on mouse pre- and peri-implantation development using a novel double-channel gas supply (DCGS) incubator (CNC Biotech Inc.) to alter the oxygen concentration during in vitro culture. Methods: The high-O₂ and low-O₂ groups were cultured from the one-cell to the blastocyst stage under 20% and 5% oxygen concentrations, respectively. In the dynamic-O₂ group, mouse embryos were cultured from the one-cell to the morula stage under 5% O₂ for 3 days, followed by culture under 2% O₂ to the blastocyst stage. To evaluate peri-implantation development, the blastocysts from the three groups were individually transferred to a fibronectin-coated dish and cultured to the outgrowth stage in droplets. Results: The blastocyst formation rate was significantly higher in the low-O₂ and dynamic-O₂ groups than in the high-O₂ group. The total cell number was significantly higher in the dynamic-O₂ group than in the low-O₂ and high-O₂ groups. Additionally, the apoptotic index was significantly lower in the low-O₂ and dynamic-O₂ groups than in the high-O₂ group. The trophoblast outgrowth rate and spread area were significantly higher in the low-O₂ and dynamic-O₂ groups than in the high-O₂ group. Conclusion: Our results showed that a dynamic oxygen concentration (decreasing from 5% to 2%) had beneficial effects on mouse pre- and peri-implantation development. Optimized, dynamic changing of oxygen concentrations using the novel DCGS incubator could improve the developmental competence of in vitro cultured embryos in a human in vitro fertilization and embryo transfer program.

• 한국토양비료학회지
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• 제50권3호
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• pp.195-202
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• 2017

The volcanic ash soils from the Jeju province have low available phosphate because of the high phosphate fixing power of the soils. Phosphorus fertilizerwas dressed after cultivating green manure crops and before cultivating potatoes in order to investigate potato yields, the available phosphate contents, and phosphorus balance in the soils. Green manure crops cultivated in this study were hairy vetch alone and hairy vetch and rye. During potato cultivation, four treatments were conducted in the experiments; NF (non fertilizer), P fertilizer ($N-P-K=0-25-0kg\;10a^{-1}$), NK fertilizer ($N-P-K=18-0-19kg\;10a^{-1}$), and NPK fertilizer ($N-P-K=18-25-19kg\;10a^{-1}$). There were no differences in the yields of potato stem and tuber from the cultivation plots of different green manure crops. However, in the plots with single-sown hairy vetch and mixed-sown hairy vetch and rye, the yields of potato stem and tuber were higher in the P fertilizer plot than in NF plot. The yield of tuber among the treatments with mixed-sown hairy vetch and rye was the highest in the NPK fertilizer plot. The available phosphate content in soils initially increased with time in all plots, but began to decrease gradually after Oct. 18. The available phosphate contents were high in the plots for phosphate fertilization, and the difference in available phosphate content between non-phosphorus fertilizer plots and phosphorus fertilizer plots increased with time. In the single-sown hairy vetch and mixed-sown hairy vetch and rye plot, the phosphorus balances in NF plot and NK fertilizer plot were very low, while those in the P fertilizer plot and NPK fertilizer plot were high. In conclusion, available phosphate contents in soil and the potato yields were increased by phosphorus fertilization when potatoes planted after cultivating hairy vetch and rye together, compared to hairy vetch alone.

• Clinical and Experimental Reproductive Medicine
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• 제44권4호
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• pp.224-231
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• 2017

Objective: We studied the association between sperm DNA fragmentation (SDF) and several clinical in vitro fertilization outcomes. Methods: We retrospectively analyzed 169 consecutive fresh IVF cycles. Semen was collected on the day of oocyte retrieval, and we assessed standard semen parameters and the SDF level (by terminal deoxynucleotidyl transferase dUTP nick-end labeling). Poor ovarian response (POR) was defined as the collection of three or fewer mature oocytes. Oocytes were inseminated by the conventional method or intracytoplasmic sperm injection. Results: SDF did not affect the fertilization or pregnancy rate, but did have a significant effect on the miscarriage rate. In the miscarriage group (n = 10), the SDF level was significantly higher (23.9% vs. 14.1%) and number of mature oocytes was significantly lower (4.3 vs. 7.6) than in the live birth group (n = 45). Multiple regression analysis showed that SDF was an independent predictor of miscarriage (odds ratio, 1.051; 95% confidence interval, 1.001-1.104). The cutoffs for the SDF level and number of mature oocytes that could predict miscarriage were > 13% and ${\leq}3$, respectively. In the low-SDF group (${\leq}13%$), the miscarriage rate was similar in POR patients and those with a normal ovarian response (NOR; 14.2% vs. 4.3%). In the high-SDF group ( > 13%), the miscarriage rate was significantly higher in the POR group than in the NOR group (60.0% vs. 13.3%, p= 0.045). Conclusion: Our study demonstrated that a high SDF level ( > 13%) was associated with a high miscarriage rate, and that it mainly contributed to miscarriage in the POR group. The results suggest that SDF measurements should be considered in couples with POR in order to predict the prognosis of the pregnancy.

• 한국가축번식학회지
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• 제20권4호
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• pp.413-421
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• 1997

체외에서 포유동물의 난자와 정자의 배양에 관한 연구는 난자의 성숙과정과 수정현상에 대한 많은 새로운 정보를 제공하였다. 동시에 체외수정의 연구로부터 얻은 결과는 또다른 의문을 제기하였다. 특히 동결융해정액을 이용한 돼지체외수정의 경우 낮은 정자의 침입율과 전핵형성율 및 높은 다정자침입(polyspermy)율은 아직도 해결해야할 문제점으로 남아있다. 돼지난자의 성숙에 관한 연구의 성과는 수정후 낮은 전핵형성율을 개선시켰으나 타동물종에 비하면 아직도 매우 낮게 나타나고 있다. 한편 동결정액의 처리를 위하여 caffeine이나 Ca2+와 같은 물질을 수정용 배지내에 첨가하는 등 수정능력획득의 유기를 위하여 여러 가지 방법이 연구되고 있지만 정자의 침입율은 아직도 낮고, polyspermy의 발생율은 높게 나타내고 있다. 따라서 정자의 침입율을 향상시키고 polyspermy를 억제하기 위하여 난관세포와의 공동배양, 난포액을 첨가한 배양액 내에서 정자의 전배양 및 정자농도의 조절은 매우 효과적인 방법으로 이용되어왔다. 그러나 수정란의 체외생산성 향상과 이와 관련된 연구를 보다 효과적으로 수행하기 위해서는 위에서 지적한 문제에 영향을 미치는 요인에 대한 보다 근본적인 이해가 요구된다.

• 한국양식학회지
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• 제8권3호
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• pp.159-170
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• 1995

참전복의 3배체 유도를 위하여 수정 12분후 및 32분 후에 저온$(0^{\circ}C\;,\;3^{\circ}C)$해수 혹은 고온$(35^{\circ}C\;,\;40^{\circ}C)$ 해수 속에서 여러 처리 지속 시간으로 3배체 유도 실험을 한 결과, 수정율은 실험군 사이에 유의한 차가 없었다. (P>0.05). 그러나 부화율과 정상발생율은 3배체구간 2배체 대조구보다 유의하게 낮았다. (P<0.05). $40^{\circ}C$의 고온처리구에서 수정율은 매우 낮았고$(0\~2.7\%)$ 부화되는 유생은 없었다. 3배체 유도율은 염색체수를 직접 계수해서 구했는데 가장 높은 3배체 유도율은 수정 12분 후에 $3^{\circ}C$ 해수에 15분 동안 처리했을 때 $(84.0\%)$였다. 참전복 2배체의 염색체 수는 2n=36이었고 3배체의 염색체 수는 3n=54이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.358-363
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• 2011

To investigate the effect of nitrogen fertilization on the quality of tropical grass silage, guinea grass grown with 3 types of nitrogen fertilizers, namely, urea, ammonium sulfate, and compound fertilizer 804, at 2 fertilization levels, 0.5 and 2.5 kg $Na^{-1}$ (0.5 N and 2.5 N, respectively), was subjected to silage fermentation. Silage fertilized with 0.5 N showed butyrate-dominant fermentation, irrespective of the type of fertilizer used. On the other hand, fermentation of silage fertilized with 2.5 N was significantly affected by the type of fertilizer used; fertilization with ammonium sulfate and compound fertilizer 804 resulted in silage that contained a large amount of butyrate and no lactate; this silage was considered to be of a significantly low quality as compared with silage fertilized with 0.5 N. Among silage fertilized with 2.5 N, the desirable butyrate-free fermentation was found only in urea-fertilized silage, which had the best quality. Grass material fertilized with a high level of urea accumulated a relatively high concentration of nitrate nitrogen (0.22% dry matter). Our results presented here suggest that nitrogen fertilizer management could affect the quality of tropical grass silage and that a relatively high concentration of nitrate in silage may promote butyrate-free fermentation even in tropical grass silage.

• 한국기후변화학회지
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• 제5권3호
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• pp.189-197
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• 2014

Carbon footprint of apple was a sum of $CO_2$ emission in the step of manufacturing waste of agri-materials, and greenhouse gas emission during apple cultivation. Input amount of agri-materials was calculated on 2007 Income reference of Apple by Rural Development Administration. Emission factor of each agri- materials was based on domestic data and Ecoinvent data. $N_2O$ emission factor was based on 1996 IPCC guideline. Carbon dioxide was emitted 0.64 kg $CO_2$ to produce 1 kg apple fruit, and carbon dioxide was emitted 43.6% in the step of the manufacturing byproduct fertilizer, 1.3% in the step of the manufacturing single fertilizer, 4.7% in the step of the manufacturing composite fertilizer, 6.3% in the step of the manufacturing agri-chemicals, 14.6% in the step of the manufacturing fuel, 11.5% in the step of the fuel combustion, 17.7% of $N_2O$ emission by nitrogen application and 0.18% of disposal of agri-materials. It is needed for farmers to use fertilization recommendation based on soil testing (soil. rda.go.kr) because scientific fertilization is a major tools to reduce carbon dioxide of apple production. The fertilization recommendation could be also basic data in Measurable-ReporTablele-Verifiable (MRV) system for carbon footprint.