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        검색결과 40

        1.
        2024.04 구독 인증기관·개인회원 무료
        The baculovirus expression system (BES) utilize the p10 or polyhedrin promoter, a very late promoter that exhibits strong transcriptional activity primarily at the end of viral infection, to produce useful recombinant proteins. The burst sequence of the very late promoter is essential for strong transcription, and VLF-1 is a transcription factor that binds specifically to the burst sequence, and it has been reported that it can regulate the amount and timing of expression of protein by the very late promoter. Recently, a VLF-1 constitutively expressing cell line was constructed to increase the production of the target protein, but the effect was minimal. In this study, to find the optimal VLF-1 expression conditions to increase target protein production efficiency, we controlled the expression of VLF-1 through various promoters and evaluated the target protein expression efficiency by the p10 promoter accordingly.
        2.
        2023.10 구독 인증기관·개인회원 무료
        표면발현(surface-display system)은 세포 또는 바이러스 표면에 목적 단백질을 고정하여 발현시킴으로써 목적 단백질에 대하여 독립적인 공간 구조 및 생물학적 활성을 부여하는 단백질 공학 기술이다. 또한 이를 이용하여 높은 중화항체 유도 및 대량생산이 가능한 삼량체의 형태로 항원 단백질의 발현 또한 가능하다. BES(baculovirus expression system)에서의 표면발현 기술은 번역 후 수정과정 및 복잡한 구조의 다양한 단백질의 발현이 가능하기 에 다른 숙주 기반 시스템보다 효율적이라고 보고되고 있다. 그러나 목적 단백질 외의 다른 표면 단백질과 발현 공간에서의 경쟁으로 목적 단백질의 낮은 생산량이 큰 문제점으로 지적되고 있다. 따라서, 이러한 BES에서 표면 발현의 생산 효율을 증대시키기 위하여, 동일한 표면 공간에 대한 단백질 간의 발현 경쟁에 대해 실험적으로 확인 후, 그를 해결하기 위하여 표면발현에 최적인 목적 단백질 발현을 위한 프로모터 선발 실험을 수행하였다. 이를 통해 BES에서 표면발현에 의한 목적 단백질의 생산 효율을 증대시킬 수 있음을 확인하였다.
        3.
        2023.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구의 목적은 스마트시티 구축의 핵심인 수소연료전지의 활용형태를 분석하고 해결방안을 제시하는 것이다. 수소연료전지를 활용하는 발전소의 경우 간헐성 문제가 없다는 장점 때문에 향후 가장 유망한 사용 형태로 분석됐다. 다만 많은 장점에도 불구하고 폭발 우려와 특정 수소 생산방식의 경우 이산화탄소 발생 문제 등으로 지역주민들의 반발이 지속적 으로 나타나고 있어 이를 해결하는 것이 스마트시티 구축의 주요 관건이 될 것으로 분석된다. 마지막으로 현재의 수소 생산 방식을 분석하고 이에 따른 문제점을 파악하여 스마트시티의 완전한 구축을 위한 해결책을 제시하였다.
        4,000원
        7.
        2019.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구의 목적은 농가의 사회·경제적 특성을 조사하여 대상 지역 쌀 생산의 기술적 효율성 수준을 분석하는 것이다. 또한 이 연구에서는 캄보디아의 쌀 생산성 수준에 영향을 미치는 요인들을 확인하고자 하였다. 이 연구에 사용된 정보는 2016년에 캄보디아 남부에 위치 하는 다케오주의 트람꺽군과 키리웡군에서 무작위로 선택된 80개의 농가를 면접 조사한 자료이다. 농가의 사회·경제적 특성을 조사하기 위하여 기술 관련 통계 자료가 활용되었다. 또한 inputorientation data envelopment analysis는 기술적 효율성 점수를 추정하는데 사용되었다. 더불어 Tobit regression은 쌀 생산의 효율성 수준에 영향을 미치는 요인을 확인하는데 사용되었다. 연구 결과에 따르면 연구 결과에 따르면 연구 분야 농가의 평균 기술 효율은 0.67인 반면, 쌀 생산업자들은 같은 생산 수준을 유지하면서도 투입 비용을 33% 절감할 수 있는 것으로 나타났다. 다케오주의 뜨람꺽군 및 키리웡군의 쌀 생산의 효율성 수준에 영향을 미치는 네 가지 요인이 발견되었다. 토빗 회귀분석 결과, 가장의 성별, 가장의 주요 직업, 쌀의 재배 횟수를 포함한 요인들이 기술적 효율성에 긍정적인 영향을 미치는 반면 심어진 종자와 품종은 기술적 효율성에 부정적인 영향을 미치는 것으로 추정되었다. 쌀 생산 규모의 효율성은 0.80로 분석되었으며, 이는 농민들이 적정 규모에 가깝게 운영 하고 있음을 나타낸다. 이는 생산관련 비효율의 원인이 투입 자원의 잘못된 배분이나 부적절한 사용으로 인한 것임을 의미 한다.
        4,000원
        8.
        2018.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Up-to-date artificial insemination (AI) using frozen sperm consider as the most widely using technology for improvement of Korean Native Cow (Hanwoo) embryo production. However, it is time consuming, required at least 15~20 years to make more than 6 generations, and their offspring number is limited. To overcome such limitations, superovulation and in vitro fertilization have been developed. For superovulation, the number of produced embryos are not enough for commercialization and donor cows need rest period. This led to use of slaughterhouse ovary for in vitro fertilization, but it is impossible to repeat the collection from the same individual and it only can improve the genetic merits of offspring for one generation. Production of embryos using Ovum Pick-Up (OPU) technique, where oocytes can be repeatedly collected from living elite donor, might overcome these limitations. In this study, we investigated the possibility of using OPU technique from donors at different age and different session periods for mass-embryo-production. Oocytes were collected from 26 donor cows twice per week, 3 - 4 months per year, between 2013 and 2016. Results showed that, the average number of embryo produced in first year used donor was significantly higher than that in second year used donor (3.89 ± 2.85 vs 3.29 ± 2.70), however, there was no significant difference between third year used donor (3.51 ± 3.32) and other groups. Taken together, our data showed that repeated using of donor up to three years is possible for in vitro embryo mass-production. Moreover, OPU can be used as suitable embryo producing technique for livestock breed improvement.
        4,000원
        9.
        2018.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        고추는 조미채소의 한 종류로 우리나라 채소시장에서 큰 비중을 차지하는 품목이다. 대부분 고추의 이용은 건고추의 분말형태인 고춧가루로 가공하여 이용되고 있으므로, 고추건조에 대한 품질과 생산성 향상이 중요한 부분이다. 따라서 본 연구에서는 고추의 건조방법에 따라 고춧가루의 품질을 좌우할 수 있는 성분의 변화에 대하여 비교하고, 생산비를 고려하여 적정 건조방법을 제시하고자 실험을 수행하였다. 건조방법으로는 관행으로 많이 이용되는 양건과 화건을 이용하였으며, 제습기를 이용한 제습건조방식을 추가 적용하여 건고추 생산성과 품질을 비교하였다. 고추의 건조방식에 따른 건조율은 화건이 85.1%로 제일 높았고, 이에 따라 고춧가루의 수분함량도 13.5%로 가장 낮게 나타났다. 고추의 색택을 좌우하는 ASTA(American Spice Trade Association) 색도는 양건처리에 비해 화건과 제습건조처리가 높은 결과를 보였다. 고춧가루의 신미성분인 capsaicinoid 함량은 양건처리에 비하여 화건과 제습건조처리에서 모두 낮게 나타나 이에 대한 추가적인 적정 건조조건에 대한 연구가 추가되어야 된다. 당함량은 건조시간이 비교적 짧았던 화건과 제습건조처리에서 양건에 비해 높게 나타났으나 두 처리간에는 유의한 차이를 보이지 않았다. 건고추 생산비용은 제습건조처리가 화건처리에 비해 9.9% 효율이 높은 것으로 나타났다. 본 연구를 통해 화건과 제습건조가 당함량의 증진과 건고추의 색 발현 측면에서는 효과적이었음을 알 수 있었다. 고추의 신미성분인 capsaicinoid함량 증진을 위해서는 화건과 제습건조처리에서 적정한 건조온도와 건조시간에 대한 연구가 추가되어야 될 것으로 판단되었다.
        4,000원
        10.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was designed to investigate the carryover effects of high-forage to concentrate (F: C) diet in bred heifers on feed intake, feed efficiency (FE) and milk production of primiparous lactating Holstein cows. The experiment was conducted for 589 days (d) from onset of pregnancy through to the end of first lactation. Twenty-four bred heifers (Body weight: BW= 345.8 ± 45.4 kg and 15 ± 1.2 mon of age) randomly assigned to two groups of 3 pens containing 4 heifers each and fed high forage (HF) diet with F: C ratio of 91.7: 8.3% and low forage (LF) diet with F: C ratio of 77.8: 22.2% throughout the pregnancy period. After calving, lactating cows were fed total mixed ration (TMR) based diet. No differences (p > 0.05) were observed in dry matter intake (DMI) of bred heifers and primiparous lactating cows in both HF and LF groups. The FE of mid-to-late lactation period was higher (p< 0.05) in HF than LF group. However, the HF group showed higher (p < 0.05) milk yield, 4 % fat corrected milk (FCM) and energy corrected milk (ECM) than LF group during the 305 d lactation. The LF group showed higher (p < 0.05) milk fat, crude protein (CP), milk urea nitrogen (MUN), solid not fat (SNF) and somatic cell count (SCC) than HF group. It is concluded that restriction of F: C ratio to 91.7: 8.3% to bred heifers has the potential carryover effects to maintain higher milk yield and FE with no adverse effect on feed intake and milk composition of primiparous lactating Holstein cows.
        4,000원
        11.
        2017.05 구독 인증기관 무료, 개인회원 유료
        The OPU technology has been largely used in order to enhance genetic improvement in domestic animals. This study demonstrated that OPU in Hanwoo can be used for the effective technique to improve the reproductive efficiency. This experiment showed the longest times of OPU ever carried out in Hanwoo. In this study four donors were selected from Hanwoo by using DNA extraction and SNP maker. Individual donors have genes which are CAPN1, CAST and FASN and that contain dominant position. CAPN1, CAST genes are often thought to be related with tenderness and FASN gene is thought to be associated with oleic acid which is identified a monounsaturated fatty acid found naturally in many plant and animal products. In experiment 1, OPU technique was used to evaluate the influence of the number of oocytes recovery rate per session. Totally 50 times OPU sessions were performed and oocytes recovery at every 10 times session was evaluated. In case of H4, the OPU session could be done around 30 times after her calving. Compared to the average number of oocytes recovery, H1 was more efficient than H3. Considering this results, the current study showed that animals have considerable individual variation in numbers of oocytes. In this study, the average recovery rate in Hanwoo is similar to the recovery rate of the Bos Taurus. Individual donors have no significant difference among group for recovery rate during 30 sessions. However, Thoese showed significant decrease in the number of oocytes recovery rate after 40 session of OPU treatment. Therefore we conclude that the Hanwoo donor is considered to be suitable for 30 times of OPU treatment. In experiment 2, OPU technique was used to evaluate the influence of the number of recovery rate monthly. The average number of oocytes recovery rate showed no significantly difference for five months. However, the number of oocytes recovery rate decreased significantly during three months after first five months experiments. In experiment 3, whether donors are parity or non-parity, the average number of oocytes recovery rate was checked. However, we could not find any significant result from this experiment. In experiment 4, the developmental rate of in vitro produced embryos from OPU was compared with that from slaughterhouse. From this, cleavage rate of oocytes from OPU is significantly less than that from slaughterhouse. In conclusion, this study included a thorough analysis of oocytes and embryo production by OPU from Hanwoo. OPU can be successfully performed under a continuous regime for 8 month in Hanwoo. The current study shows the clear proof that OPU could be adopted to produce oocytes and embryos of better quality as an advanced technique replacing the usage of MOET in Korea. Finally, elucidation the basis for numerous oocytes obtained from Hanwoo may contribute to a better understanding of reproductive physiology in cattle.
        6,000원
        12.
        2015.05 구독 인증기관 무료, 개인회원 유료
        Pigs are considered an ideal source of human disease model due to their physiological similarities to humans. However, the low efficiency of in vitro embryo production (IVP) is still a major barrier in the production of pig offspring with gene manipulation. Despite ongoing advances in the associated technologies, the developmental capacity of IVP pig embryos is still lower than that of their in vivo counterparts, as well as IVP embryos of other species (e.g., cattle and mice). The efficiency of IVP can be influenced by many factors that affect various critical steps in the process. The previous relevant reviews have focused on the in vitro maturation system, in vitro culture conditions, in vitro fertilization medium, issues with polyspermy, the utilized technologies, etc. In this review, we concentrate on factors that have not been fully detailed in prior reviews, such as the oocyte morphology, oocyte recovery methods, denuding procedures, first polar body morphology and embryo quality.
        4,000원
        13.
        2014.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Sexed semen is commonly used for the production of calves of the desired gender. Gender selection is important in animal production industries. For example, female cattle are required for the dairy industry while males are preferred in the beef cattle industry. The present study was to assess the in vivo embryo production efficiency using the semen separated according to sex during superovulation in Hanwoo. Seventy Hanwoo donor cows were flushed on day 7 of estrus cycle with same FSH and artificial insemination by the same technicians. Embryos were recovered on 7 days after the third insemination by flushing the uterus with embryo collection medium. KPN semen straws used artificial insemination contained 20 million sperm (total number 60 million per donor). Sex-sorted semen straws contained 4 million sperm (total number 12 million per donor). The results obtained were as follows: No differences were observed in the efficiency of superovulation rates on KPN semen 87%, and sexed semen 100%, respectively. The mean numbers of total embryos are each 12.58±8.31 and 13.25±7.86. The mean numbers of transferable embryos, sexed semen were significantly lower than KPN semen (3.75±1.98 vs. 8.23±6.07, P<0.05). The rates of unfertilized embryos from superovulation using sexed semen were significantly higher than KPN semen (50% vs. 15%, P<0.05). The rate of degenerated 2-cell embryos from sexed and KPN semen was 60.87% and 11.11%, respectively (p<0.05). In conclusion, these results indicate that superovulation using sexed semen was useful, but efficient embryo production was important to reducing the damage caused by the Flowcytometer-based sperm sorting procedure.
        4,000원
        14.
        2014.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The jet production efficiency of radio galaxies can be quantified by comparison of their kinetic jet powers Pjet and Bondi accretion powers PB. These two parameters are known to be related linearly, with the jet power resulting from the Bondi power by multiplication with an efficiency factor of order 1%. Using a recently published (Nemmen & Tchekhovskoy 2014) high-quality sample of 27 radio galaxies, I construct a PB − Pjet diagram that includes information on optical AGN types as far as available. This diagram indicates that the jet production efficiency is a function of AGN type: Seyfert 2 galaxies seem to be systematically (with a false alarm probability of 4.3 × 10−4) less efficient, by about one order of magnitude, in powering jets than Seyfert 1 galaxies, LINERs, or the remaining radio galaxies. This suggests an evolutionary sequence from Sy 2s to Sy 1s and LINERs, controlled by an interplay of jets on the one hand and dust and gas in galactic nuclei on the other hand. When taking this effect into account, the PB − Pjet relation is probably much tighter intrinsically than currently assumed.
        3,000원
        15.
        2013.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 강원도 고랭지 배추의 생산 효율성을 파악하기 위해 공식 통계에 대한 분석과 미시자료에 대한 계량경제학적 분석을 행하였다. 그리고 본 연구는 상대적인 평가를 통해 비효율적인 농가의 원인을 찾아보고자 한다. 또한 Tobit모형을 이용해 생산 효율성에 대한 결정요인을 분석하고자 한다. 이러한 분석결과를 종합하여 고랭지 배추 재배 농가를 효율적인 농가와 비효율적인 농가를 구분하고, 그러한 특징을 분석하여 비효율적인 농가에 대한 효율성 제고 방안을 제시하고자 한다.
        4,600원
        16.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The study was conducted to investigate the comparison of pregnancy rate and transferable embryos produced by genetically superior Korean cows (Hanwoo) of livestock farms. Eighteen Hanwoo donors were superovulated with gonadotropin for 4 days combined with Progesterone Releasing Intravaginal. Embryos were recovered 7 days after the second insemination by flushing the uterus with embryo collection medium. No differences were observed in the efficiency of rate of superovulation in groups A (low nutrition) and B (highnutrition) it was observed to be 100.0% and 87.5%, respectively. The mean numbers of total embryos were 10.8±3.4 and 8.9±2.5, and transferable embryos were 7.5±3.3 and 4.0±1.5 in groups A and B, respectively. The pregnancy rates after embryo transfer were 23.5%, 20.0%, C 80.0% and 55.6% in farm A, B, C, and D, respectively. In conclusion, results suggest that superovulation could be used quite effectively to raise superior Hanwooembryos. However, physical and biological condition of recipients greatly affects the rate of pregnancy.
        4,000원
        17.
        2012.06 구독 인증기관·개인회원 무료
        The objective of the current study was to describe in vitro embryo production in Hanwoo, analyzing oocytes yield and embryo production. The effects of oocytes production and the number of OPU procedures per animal on embryo production were also evaluated. OPU was done every 3~4 days during experimental period and collected oocytes were fertilized in vitro in both OPU and needle puncture groups. First, we compared the recovery rate of oocytes based on OPU session (Experiment 1). The average of collected oocytes was calculated from every 10 session. The average number of total oocytes recovered per animalonsessionwas 5.16 (mean). Second, we compared the recovery rate base on collection period of OPU (Experiment 2). The following results show the difference of the number of recovered oocytes in every month during the procedure between the months of session. Every animal shows the constant number of recovered oocytes for the first 5 months. However, the recovery rate of oocytes was decreased from month 6 to 8. Third, we compared the developmental rate to blastocyst in two groups (Experiment 3). Oocytes by needle puncture were fertilized with frozen-thawing semen; the cleavage rate 24~48 h after in vitro fertilization (IVF) was 75.8% and blastocyst development rate was 18.8% in needle puncture group. Even though there is lower cleavage rate after IVF in OPU group (61.1%), blastocyst development rate was higher compared with needle puncture group (28.4%). In conclusion, Blastocyst developmental rate could be increased by OPU than classical method of needle puncture. Improvement of bio- technique in collecting oocytes could be applied to understand the reproductive physiology in cattle, expecially Hanwoo. Therefore, further investigation should be done to clarify the efficiency and advantage of OPU involved in reproduction in animals and human being.
        18.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The present research was carried out to evaluate the possibility of increasing female offspring production ratios using artificial insemination buffer (AIB) before artificial insemination (AI). In this experiment, we optimized AIB composition, made an AIB gun and analyze factors affecting AI non-return rate after AIB treatment. The AIB was made with the base of Tris-buffer supplemented with L-arginine and several other chemicals that might reduce the motility of male sperm compared to the female counterpart, therefore, increasing the possibility of fertilization by female sperm. AIB must be deposited into to cervix by AIB gun. After 15 min of AIB deposition, frozen semen was deposited into the same place. A total of 348 cattle were inseminated with AIB insemination, and there were no significant differences between AIB and traditional AI non-return rates (56.8% vs. 55.7%). The AI non-return rate in AIB group, however, differed significantly among 7 Hanwoo farms. The parturition numbers ( to ) of cows did not affect AIB AI rate. The proportion of AIB AI success rates was significantly higher in Hanwoo cows than in dairy cows (61.0% vs. 48.7%), but the average AI success rate did not differ significantly between AIB and conventional AI (56.8% vs. 55.7%). The female offspring production rate in to cervix deposition place was significantly higher than that in the uterus body (77.7% vs. 59.6%, p<0.05). The injection volume of AIB in 5 and 10 ml was significantly higher than that in 2 ml (77.7%, 78.7% vs. 51.8%, p<0.05), but there were no differences in AIB injection volume between 5 and 10 ml. The best exposure time of AIB in the cervix was 10 to 15 min rather than 5 min (79.2%, 77.2% vs. 52.6%, p<0.05). AIB therefore needs to have an exposure time of at least over 10 min for a higher production rate of female offspring. In conclusion, AIB could be used in AI industry to increase the female offspring ratio and AIB AI can increase the AI success rate.
        4,000원
        19.
        2011.10 구독 인증기관·개인회원 무료
        The present research was carried out to evaluate the possibility of female offspring production using artificial insemination buffer (AIB) before artificial insemination (AI). To do it, we carried out the optimization of AIB, making of AIB gun and analysis of affecting AI rate after AIB treatment. AIB made with the base of Tris‐buffer supplemented with L‐arginine and several materials that could be reduced the motility of male sperm compared with female one. This mean that female sperm could be increased the possibility of fertilization with ovum compared with male one. AIB must be deposited into 2nd to 4th cervix by the guide of AIB gun. After 15 min of AIB insertion, frozen semen was deposited into same place after. Total 352 cattle were inseminated with AIB insemination and was not significant difference between AIB and traditional AI rate (56.8 vs. 55.7%). However, AIB AI rate was significantly differs among 12 different farms. The parturition number of cows did not effect on AIB AI rate among 1st to 7th parturition number of cows. The proportion of AIB AI success rates in hanwoo cows was significantly higher than in dairy cows (61.0% vs. 48.7%), but the average AI success rate was not different between AIB and conventional AI (56.8% vs. 55.7%). The female offspring production rate in 2nd to 4th cervix deposition place was significantly higher than in uterus body (77.7% vs. 59.6%, p<0.05). The injection volume of AIB in 5 and 10 ml was significantly higher than in 2 ml (77.7, 78.7 vs. 51.8%, p<0.05), but not different between 5 and 10 ml ABI volume. The best exposure time of AIB in the cervix was 10 and 15 min rather than that of 5 min (79.2%, 77.2% vs. 63.2%, p< 0.05), and so AIB have to expose at least 10 min to get higher female offspring. In conclusion, AIB could be used in AI industry to produce female offspring and also AIB AI can be increased the AI success rate compared with traditional AI rate.
        20.
        2009.08 구독 인증기관·개인회원 무료
        Forage production and water use efficiency (WUE) of Lucerne were investigated in three varieties at different water availabilities. Forage production decreased with the severity of soil water availability. At 50% field water capacity (FWC), forage production dropped but in two varieties, Algonquin and Longdong, was still high and from 75%FWC to 50%FWC, forage production in Longdong decreased at the least rate. The greatest leaf WUE was observed in Longdong at all soil water availabilities. From 75%FWC to 50%FWC, it increased in Longdong and Xinjiangdaye, but decreased in Algonquin. With the severity of water deficit, δ¹³C value increased in all three varieties. At the same water availability, the greatest value was observed in Longdong. It suggested that moderate water stress can improve WUE in Lucerne. Longdong is to some extent more efficient in water use and may be more drought-tolerant with more steady production at moderate water deficit.
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