• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.199-205
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• 2020

Cryopreservation of semen is useful for animal breeding via artificial insemination (AI). However, the use of frozen-thawed boar semen is limited due to cryodamage. The aim of this study was to investigate the effects of different concentrations of MitoTEMPO (a mitochondria-targeted antioxidant) in lactose-egg yolk (LEY) extenders on kinetic characteristics of frozen-thawed boar sperms. Semen samples were collected from mature Duroc boars (2~3 years old) and cryopreserved in LEY extenders containing 0, 0.5, 5, 50, and 500 μM MitoTEMPO. The kinetic characteristics of frozen-thawed sperms were determined 0 and 30 min after thawing using computer-assisted sperm analysis (CASA). Results indicated that sperm motility immediately after thawing was significantly higher with 5 and 50 μM (50.46±2.71% and 46.96±2.66%, respectively) than with 500 μM MitoTEMPO (35.40±2.95%) (P<0.05). However, there were no significant differences in other kinetic characteristics except motility. In conclusion, the addition of MitoTEMPO to the sperm freezing extender may have a beneficial effect on motility of post-thawed boar semen.

• Journal of Embryo Transfer
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• v.18 no.3
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• pp.195-201
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• 2003

This study was carried out to establish most suitable freezing condition, to evaluate the different condition of freezing and thawing rates on the viability and motility of frozen canine spermatozoa. The ejaculated semen was added to obtained 200∼400 ${\times}$ 10$^{6}$ /$m\ell$ with extender I and was cooled to 4$^{\circ}C$ over 30, 60 and 120 minutes. And then, semen was diluted with extender II containing 4, 6 and 8％(v/v) glycerol for 60 min, respectively and packaged in 0.5$m\ell$ straw, equilibrated far 30, 60 and 120 min at 4$^{\circ}C$ and cryopreserved in liquid nitrogen vapor at different distance(3, 5, 7 and 9 cm, respectively), plunged into nitrogen tank. Samples were thawed by placing straws into 27, 37, 47, 57$^{\circ}C$ water bath for 120, 20 and 12 sec, respectively. The results were as follows; 1. The survival and motility rate immediately post-thawing was significantly higher in samples frozen in 4％ glycerol than 6 or 8％ glycerol(P< 0.05). 2. According to equilibration time at 4$^{\circ}C$, the survival and motility rate immediately post-thawing was significantly higher in samples frozen after 60 min equilibration than 30 or 120 min equilibration(P<0.05). 3. Freezing in distance of 5 cm from liquid nitrogen yield better survival and motility rate than the others(3, 7 or 9 cm)(P<0.05). 4. The effect of thawing rate on sperm survival were higher when the thawing was done at 37$^{\circ}C$ for 120 sec(P<0.05).

• Journal of Embryo Transfer
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• v.30 no.1
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• pp.45-50
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• 2015

The purpose of this study is to produce wanted sex progeny of genetically confined White Hanwoo (albinism) with preselected sex sperm. One bull of White Hanwoo was chosen for semen donor and X sperm was sorted by MoFlo XDP cell sorter. To compare the pregnancy and birth rates, KPN straw was used as control, total number of unsorted sperm was $20{\times}10^6/straw$. Sexed X frozen semen with $20{\times}10^6$ cells or $4{\times}10^6$ cells per straw were in seminated twice on Hanwoo heifers. The abnormality of the sexed X semen was $24.9{\pm}7.31%$ and distal reflex abnormality of mid piece was significantly (p<0.05) higher (11.7%) compared with that of KPN 768 (5.6%). There were no differences on the pregnancy and birth rates between $2{\times}10^6$ cells or $4{\times}10^6$ cells of X-sperm but KPN semen showed significant differences (p<0.05). The pregnancy rates of KPN 768, $2{\times}10^6$ cells and $4{\times}10^6$ cells X-sperm of White Hanwoo cattle were 85.0%, 26.3% and 50%. The birth rates were 80.0%, 15.8% and 21.4%, respectively. The female offspring rates of KPN 768, $2{\times}10^6$ cells and $4{\times}10^6$ cells X-sperm of White Hanwoo cattle were 43.8%, 100% and 100% (p<0.05). These results indicated that sex sorted White Hanwoo could be used for the production of wanted progeny with $2{\times}10^6$ cells/straw for AI. To increase the efficiency of calf production, the sperm number of sex sorted semen will be optimized for sex selection of White Hanwoo progeny.

• Korean Journal of Construction Engineering and Management
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• v.25 no.2
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• pp.23-35
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• 2024

This study analyzed the correlation between each of the 12 influencing factors in FAR 16.04 and the decision-making process for construction contract types, using data from a total of 2,406 DoD Construction Acquisitions spanning from 2008 to 2022. The study considered 12 independent variables, grouped into 4 Characteristics with 3 factors each. Meanwhile, all other contract types were categorized into two types: Firm-Fixed-Price (FFP) and Cost-Reimbursement Contract (CRC), which served as the dependent variables. The findings revealed that FFP contracts significantly dominated in terms of acquisition volume. In line with prevailing beliefs, logistic data analysis and Analytical Hierarchy Process (AHP) analysis of Relative Weights from Experts' Survey demonstrated that independent variables like Uncertainty of the Scope of Work and Complexity found out to be increasing the likelihood of selecting CRC. The number of contractors in the market does indeed influence the possibilities of contract decision-making between CRC and FFP. Meanwhile, the p-values of the top 3 influencing factors on CRC from the AHP analysis-namely, Appropriateness of CAS, Project Urgency, and Cost Analysis-exceeded 0.05 in the binominal regression results, rendering it inconclusive whether they significantly influenced the construction contract type decision, particularly with respect to payment methods. This outcome partly results from the fact that a majority of respondents possessed specific experiences related to the USFK relocation project. Furthermore, influencing factors in construction projects behave differently than common beliefs suggest. As a result, it is imperative to consider the 12 influencing factors categorized into 4 Characteristics areas before establishing acquisition strategies for targeted construction projects.

• Clinical and Experimental Reproductive Medicine
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• v.23 no.1
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• pp.7-9
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• 1996

Here, A forty year old patient is presented, showing azoospermia following vasovasostomy. The bilateral testicular biopsies were performed to confirm whether ductal obstruction due to vasovasostomy or testicular failure existed. The finding of biopsy was spermatogenic arrest. After completion of medical testicular stimulation with clomiphene citrate and pentoxifilline for 3 months, repeat vasovasostomy was performed. Semenanaylsis revealed normal sperm parameters after operation. Necessity of testicular biopsy before deciding repeat vasovasostomy, accuracy of testicular biopsy, efficacy of testicular stimulation in the patient with spermatogenic arrest and effect of testicular biopsy on testicular fuction are discussed.

• Korean Journal of Animal Reproduction
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• v.10 no.2
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• pp.188-191
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• 1986

This experiment was carried out to examine the correlation among the semen characteristics of Holstein bulls. Seventy-two samples of semen were collected from 6 Holstein bulls, 2 to 10 years old. The characteristics of the semen were estimated by ordinary methods. The results obtained in this experiment were summarized as follows: 1. Semen characteristics on an average were 6.0 ml of volume, 16${\times}$108/ml of concentration, 92.4${\times}$108 of total sperm number(TSN), 72.1% of motility and 4.6% of abnormality. 2. Semen volume was positively high correlated (P<0.01) with total sperm number, but negative correlation was observed with the sperm motility (P<0.05) and semen concentration. 3. In relation to their age, older bulls semen volume and total sperm number were increased (P<0.01), but semen concentration and motility were decreased (P<0.01).

• Korean Journal of Animal Reproduction
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• v.11 no.1
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• pp.22-25
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• 1987

This study was carried out to investigate the effects of imported pellet frozen semen on sperm motility and NAR acrosomes after thawing, and the farrowing rates, litter sizes and preweaning body weights after artificial insemination. A total of 28 sows of Landrace, Large White and Duroc were inseminated at the Chungnam Provincial Animal Breeding Station. The results obtained are summarized as follows: 1. Landrace andLarge White had higher sperm motility than Duroc by about 20% and had higher NAR acrosomes by about 10%. 2. The farrowing rates of Landrace, Large White and Duroc were 63.6, 55.6 adn 50.0%, respectively. The number of pigs born alive per litter were larger in Landrace and Large White as compared with Duroc (p<.01). 3. Duroc had the highest mean pig weight at birth, followed by Landrace and Large White (p<.01). The mean pig weights at 21 days and 56 days had no significant differences between the breeds.

• Journal of Veterinary Clinics
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• v.18 no.1
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• pp.44-47
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• 2001

Semen were collected from 9 male dogs and frozen by liquid nitrogengas. Frozen semen were thawed at 7$0^{\circ}C$ for 8 seconds. About $2{\timss}10^8$ sperm per insemination were inseminated to 10 bitches (3 Retrievers, 4 Chihuahuas, 1 Yorkshire Terriers, 1 Maltese, and 1 Poodle) at three and six days after the estimated peak of luteinizing hormone. For small breed dogs, uretero-renoscope (Kahl Storz, Germany, 12.5 Fr) was used for trans-cervical insemination, whereas cystoscope(Kahl Storz, Germany, 22Fr) was used for large breeds (Retrievers). Pregnancy was diagnosed by ultrasonography at 30 days after insemination. All of 3 Retrievers (100.0%) and 3 bitches of 7 small breed dogs (42.9%) were conceived (60.0% in total). This result indicated that trans-cervical insemination using endoscope is an effective method for AI with frozen semen not only for large breed dogs such as Retriever but also for small breeds.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.204-204
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• 2004

조류에서는 포유류와 달리 암컷이 후대의 성을 결정하는 것으로 알려져 있다. 암컷은 일생동안 산란할 난자를 가지고 태어나며, 이들 난자가 배란되어 정자와 만나면서 수정됨과 동시에 닭의 성이 결정되어진다. 본 연구는 산란계가 어떤 특이적 경향으로 암 혹은 수(W, Z) 난자를 배란하는지의 여부를 인공수정 및 배양의 방법들을 이용하여 수행하였다. 본 연구는33개체의 37주령 Single Comb white Leghorn 암컷들을 사용하여 13주 (37∼50주령) 동안 연속적으로 수행하였다. 인공수정은 동종 동계의 수탉 정액을 이용하였으며, 발생이 완료된 후대의 성비 판별은 다음과 같은 방법으로 수행하였다. (중략)

• Journal of Embryo Transfer
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• v.6 no.1
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• pp.41-45
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• 1991

소와 견에 있어서 Unopette가 정자의 형태학적 검사 및 정자농도의 검사를 위하여 사용될 수 있는가를 알아 보기 위하여본 연구를 수행하였다. 소정액 및 견정액을 Unopette에 희석한 후 3-5$^{\circ}C$에 보존하면서 시간경과에 따라서 위상차현미경하에서 관찰하여 다음과 같은 결과를 얻었다. 1. Unopette를 사용하여 관찰한 정자는 48시간까지는 hematoxylin-eosin을 사용하여 정자보다는 높은 정상정자율을 나타내넜다. 2. Unopette를 사용한 정자는 정자농도에 있어서 대조군 정자에 비하여 24시간까지는 큰 차이를 나타내지 않았다. 3. 따라서 Unopette는 정자의 형태학적 검사 및 정자농도의 검사를 위하여 유용하게 사용될 수 있다는 사실을 알 수 있었다.