The Jeju Black Cattle (JBC) are a type of traditional Korean native cattle with a characteristic black fur that covers the entire body. Semen analysis is the most commonly used procedure to evaluate male fertility potential. This study was to evaluate the quality of 10 JBC bulls belonging to Jeju Special Self-Governing Province Promotion Institute. [JBC A∼J grade]. The freezing medium (20% egg yolk plus 20% triladyl) was added in semen sample to a final concentration of 100×106 sperm/ml. For sperm cooling, diluted semen was filled in 0.5 ml plastic straws and then kept in refrigerator at 4°C for 2 h. They were placed in 7 cm over liquid nitrogen (LN2) vapor for 10 min and then directly plunged into LN2 for storage. Thawing was done by transferring the frozen straws into water bath at 37°C for 30 sec for analysis. The sperm motility, vitality and morphology in each group was assessed using the Sperm Analysis Imaging System (SAIS Plus; Medical Supply Co, Ltd., Korea), eosin-nigrosin stain and diff-quik kit. There was no difference in the motility of the fresh groups (87.4 ~ 100%), while it was difference in the frozen-thawed groups (42.8 ~ 98.6%) (p<0.05). The best motility was shown in JBC-B (100/fresh and 98.6%/frozen-thawed). There was significant difference in the vitality of the fresh group (19.8 ~ 59.2%) and frozen-thawed group (21.2 ~ 49.8%)(p<0.05). The highest vitality was also shown in JBC-B (59.2/fresh and 49.8%/frozen-thawed). Morphologically, in fresh semen the highest normal ratio was indicated in JBC-E (90.9%) and in frozen-thawed group the highest was in JBC-C (90.2%). These results demonstrated that the analysis including motility, vitality and morphology of fresh or frozen-thawed semen is valuable to select the high quality sperm using for reproduction.

Preimplantation embryonic production in vitro is important in human assisted reproductive technology and animal embryo engineering. Icariin (ICA) is one type of flavonoids and a main component isolated from the stem leaf of Epimedium brevicornum. Flavonoids, which are among the best well-studied natural antioxidants, have been demonstrated to be active in clearing reactive oxygen species (ROS). The purpose of this study was to investigate the effects of ICA treatment during porcine oocyte in vitro aging and their in vitro developmental competency after parthenogenetic activation (PA). Porcine oocytes were matured in vitro for 44 h (control) and for an additional 24 h in the presence of 0, 5 μM ICA (aging, ICA-5), respectively. This study investigated the effects of ICA on nuclear maturation, ROS level, apoptosis index, and the developmental capacity of aged porcine oocytes. Oocyte survival was not different in aging group compared to control or ICA-5 group. The increased ROS level during in vitro aging was prevented in ICA-5 group, while GSH level was not decreased. The decrease of normal spindle formation during in vitro aging was prevented in ICA-5 group. After PA, although the cleavage rate was not different among treatment groups, the blastocyst formation was significantly higher in control and ICA-5 group than in aging group. However, there was significantly difference in the apoptotic index of the ICA-5 group, while it was no difference in the total cell number of the ICA-5 group. (p<0.05). Therefore, this result demonstrated that the ICA is an effective agent to prevent the deterioration during in vitro aging of porcine oocytes.

One of the major hallmarks of uterine diseases is disruption of ovarian steroid hormone control of uterine cell proliferation and differentiation. Estrogen (E2) stimulates proliferation of uterine epithelial cells while progesterone (P4) is inhibitory to E2-mediated proliferation of the epithelium. Mitogen inducible gene 6 (Mig-6) is an important mediator of P4 signaling to inhibit E2 signaling in the uterus. Uterine-specific knockout of Mig-6 caused endometrial P4 resistance and infertility. Levels of ErbB2 (also known as HER2) and phospho-ERK1/2 are significantly higher in Mig-6 knockout mice as well as infertile women with endometriosis. To determine the interplay between Mig-6 and the Erbb2 signaling pathway in the uterus, we generated mice with Mig-6 and Erbb2 conditionally ablated in progesterone receptor-positive cells (Pgrcre/+ Mig-6f/f Erbb2f/f; Mig-6d/d Erbb2d/d). Mig-6d/d mice were infertile whereas control and Mig-6d/d Erbb2d/d mice exhibited normal fecundity. The uterine horns of Mig-6d/d mice had no implantation sites, whereas control and Mig-6d/d Erbb2d/d mice had averaged implantation sites. Additionally, aberrant increment of epithelial proliferation in uterus of Mig-6d/d mice did not show in Mig-6d/d Erbb2d/d mice uterus at pre-implantation stage. Microarray analysis revealed that almost altered genes in Mig-6d/d mice were recovered their expression levels in Mig-6d/d Erbb2d/d mice. The altered pathways such as cell-cycle control, DNA replication, and modification processes by Mig-6 ablation were rescued in Mig-6d/d Erbb2d/d mice. The infertility seen in Mig-6d/d mice is recovered in Mig-6d/d Erbb2d/d mice. These results suggest that Mig-6 mediates a critical P4 function to inhibit E2 signaling by inhibiting ErbB2 signaling. As MIG-6 is a mediator of P4 signaling, the activity of which can suppress unopposed-E2 signaling, our studies provide a potential new drug target for the intervention of female infertility.

Thrombin-induced platelet microbicidal protein (tPMP) is a small cationic peptide that exerts potent in vitro microbicidal activity against a broad spectrum of human pathogens, including Staphylococcus aureus and Streptococcus rattus BHT. Earlier evidence has suggested that tPMP targets and disrupts the bacterial membrane. However, it is not yet clear whether membrane disruption itself is sufficient to kill the bacteria or whether subsequent, presumably intracellular, events are also involved in this process. In this study, we investigated the microbicidal activity of rabbit tPMP toward S. rattus BHT cells in the presence or absence of a pretreatment with antibiotics that differ in their mechanisms of action. The streptocidal effects of tPMP on control cells (no antibiotic pretreatment) were rapid and concentration-dependent. Pretreatment of S. rattus BHT cells with either penicillin or amoxicillin (inhibitors of bacterial cell wall synthesis) significantly enhanced the anti-S. rattus BHT effects of tPMP compared with the effects against the respective control cells over most tPMP concentration ranges tested. On the other hand, pretreatment of S. rattus BHT cells with tetracycline or doxycycline (30S ribosomal subunit inhibitors) significantly decreased the streptocidal effects of tPMP over a wide peptide concentration range. Furthermore, pretreatment with rifampin (an inhibitor of DNA-dependent RNA polymerase) essentially blocked the killing of S. rattus BHT by tPMP at most concentrations compared with the respective control cells. These results suggest that tPMP exerts anti-S. rattus BHT activity through mechanisms involving both the cell membrane and intracellular targets.

The synthesis of silver coated iron base alloy (Sendust : Fe-Si-Al) powder having the both effects of shielding and suppressing of electromagnetic wave was studied. Depending on thickness of silver coating layer, the electromagnetic properties of the dispersed particles complexed with organic binder were examined. It is proposed that the silver coated sendust flake powders with controlled electrical properties and thickness can be used as thin microwave absorbers in quasi-microwave frequency band.

The effects of compaction pressure and sintering temperature on the densification of Fe-40wt%Ni alloy nanoparticles were analyzed. The Fe-Ni nanoparticles were fabricated by an arc-discharge method and then, compacted at three different pressures and sintered at 550 to . Densification was completed at temperature as low as and high-pressure compaction was found to enhance densification. Densification behaviors and microstructure developments have been investigated through density measurements, electron microscopies, and hardness measurements.

Small powder size is very useful in achieving detailed structures. STS 316 nanopowders with an average diameter of 100 nm and were utilized to produce feedstock. The mixing behavior of the feedstock indicated that the nanoparticle feedstock produced the highest mixing torque at various powder loading compared to the micropowder feedstock. The nanoparticles feedstocks showed that elastic properties are dominant in flow behavior and high viscosity. Conversely the micropowders feedstocks, viscous properties are dominant in flow behavior and less viscosity, nanopowders feedstock perform lower flow activation energy than feedstock with bigger particles.

이 연구는 일반적인 인지이론을 조종사 기술의 범위로 확대시켜, 조종사가 얼마나 빠르고 정확하게 상황인식을 하는지를 제시문과 비행 장면 일치성 측정을 통해 알아보았다. 이 연구의 목적은 두 가지 측면의 변인에 따라 상황인식이 전문성의 영향을 받는지를 알아보는 것이다. 비행 요소간의 관계를 나타내는 비행 상황 변인들과 비행 요소의 내용을 나타내는 비행 상황 변인들 모두 비행 상황인식에 영향을 주었다 그리고 작업기억은 다양한 정보들을 통합시키는 데 결정적인 역할을 하는 것으로 나타났다. 이러한 결과는 비행 상황인식의 바탕인 인지적 과정을 나타내는 구조화통합 모델의 이론적 틀 안에서 설명되어진다.

This paper has applied a simple model to the mass transfer mechanism of Cr(VI) with crownether in a batch-type, supported liquid membrane module. Concentration at pH 3 are as follows : 0.012 kmol/m3≤18-crown-6≤0.036 kmol/m3 and 20 g/m3≤ Cr(VI)≤500 g/m3. The measured values of forward- and backward-reaction rate constants between Cr(VI) and 18-crown-6 were used to simulate the model with the mass conservation equation and associated boundary conditions. Comparison between the experimental and simulated facilitated factor of Cr(VI) transport led to classification of reaction regions.

목적: 본 연구의 목적은 경쟁불안에 대한 개념적 구조를 파악한 후 관련 내용을 토대로 타당성과 신뢰성이 있는 축구선수용 경쟁불안 측정 도구를 개발하는 것이다. 방법: 본 연구에서는 질적 분석 단계 106명, 본 조사 단계 291명, 외적 타당도 확보 단계 176명, 총 축구선수 573명이 참여하였다. 질적 자료는 개방형 질문과 면담을 통해 자료를 수집했으며, 양적 자료는 자기평가 기입법으로 자료를 수집하고 SPSS 18.0 Version과 AMOS 20.0 Version을 통해 분석되었다. 결과: 첫째, 경쟁불안은 인지 불안, 수행 불안, 환경 불안, 신체 불안으로 4개의 일반 영역으로 범주화되었다. 둘째, 문항 분석, 신뢰도 분석, 탐색적 요인분석을 통해 17문항을 제거한 후 축구선수들 의 경쟁불안 4요인 24문항을 추출하였고, 확인적 요인분석을 통해 측정 도구의 적합도를 확인하였다. 셋째, 개발 된 축구선수 경쟁불안 측정 도구는 수렴 타당도, 구인 동등성 검증, 잠재평균 분석을 통해 외적 타당성을 확보하 였다. 결론: 축구선수들의 경쟁불안 측정 도구는 선수의 불안을 측정하는 것에 국한하지 않고 선수들의 경기력 향상을 도모할 수 있는 실질적인 정보를 제공할 수 있을 것으로 기대한다.

Karyotypes were established in the eight Korean native species of the genus Iris. Chromosome numbers were 2n=50 in I. koreana and 2n=42 in I. uniflora var. carinata and their karyotype formulas were K = 2n = 50 = 14m + 28sm + 8st and K = 2n = 42 = 16m + 26sm, respectively. I. dichotoma and I. pseudoacorus were diploids of 2n=34. However, they showed different karyotype formulas: K = 2n = 34 = 26m + 6sm + 2st in I. dichotoma and K = 2n = 34 = 8m + 24sm + 2st in I. pseudoacorus. I. setosa, and I. pallasii var. chinensis carried the same chromosome numbers of 2n=40, but they showed different patterns of karyotype formula: K = 2n = 40 = 22m + 14sm + 4st in I. setosa and K = 2n = 40 = 26m + 12sm + 2st in I. pallasii var. chinensis. I. sanguinea was a diploid of 2n=28 and the karyotype formula was K = 2n = 28 = 14m + 14sm. I. ensata var. spontanea was a diploid of 2n=24 and the karyotype formula was K = 2n = 24 = 10m + 14sm. Each species showed characteristic chromosome composition with a pair of satellite chromosome except I. koreana with three pairs of satellite chromosomes. The chromosomes of I. dichotoma and I. uniflora were comparatively short, while the chromosomes of I. ensata were remarkably bigger than those of other species. These cytological data will give a useful information for the identification and breeding program of the Iris plants.

The chromosome numbers and karyotypes were investigated in four Korean native species of the genus Hosta. The chromosome complements were diploid of 2n=60 in H. japonica var. lancifolia Nakai and H. capitata Nakai, aneuploid of 2n=59 in H. minor (Bak.) Nakai, and modified triploid of 2n=92 in H. longipes (Fr. et Sav.) Matsumura. All the species carried four sets of distinctly large chromosomes of which the chromosome types were telocentrics or subtelocentrics with 4.4~7.2 μm in length. The other chromosomes were meta-, submeta, subtelo-, or telocentric types and showed gradual length degradation in the range of 1.0~3.0 μm. The satellites appeared vestigially in a pair or a triplet set of chromosomes which depends on the species. New chromosome number and karyotype in H. longipes were the first report in this species. The structural rearrangement was suggested to explain the modified triploid composition of 2n=92.

This study was carried out to compare chromosomal characteristics between Atractylodes japonica and A macrocephala. Cytogenetic analysis was conducted based on karyotype analysis and physical mapping using fluorescence in situ hybridization. As a result of karyotype analysis by feulgen staining, somatic chromosome numbers of A. japonica and A. macrocephala were 2n=24. The length. of the mitotic metaphase chromosomes of A. japonica ranged from 0.70 to 1.60μm with a total length. of 12.11μm and the homologous chromosome complement comprised six metacentrics, five submetacentrics and one subtelocentrics. On the other hand, the length of the mitotic metaphase chromosomes of A. macrocephala ranged from 0.90 to 2.35μm with a total length of 16.58μm and the homologous chromosome complement comprised seven metacentrics and five submetacentrics. The total length of A. japonica chromosomes was shorter than that of A. macrocephala, but A. japonica had one subtelocentrics (chromosomes 4) different from A. macrocepha1a. chromosomes. The F1SH technique using 17S and 5S rDNA was applied to metaphase chromosomes. The signals for 17S rDNA were detected on the telomeric regions of chromosomes 4 and 5 in both A japonica and A. macrocephala. The 5S rDNA signal was found in the short arm of chromosome 1.