• Proceedings of the Korean Nuclear Society Conference
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• 1998.10a
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• pp.344-344
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• 1998

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2002.02a
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• pp.48-48
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• 2002

• Journal of Power System Engineering
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• v.8 no.4
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• pp.17-23
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• 2004

A delivery ship is used to handle the cargo with the crane to/from the ships. The ship is inclined in the direction of a cargo which is hung on a crane. In this case, a arc shaped rail should be in the equilibrium state to get good anti rolling performance. In this study, a device and control algorithm are developed to take accurate and quick equilibrium of the rail. The device is composed of a hinged immovable support and two screw jacks. And the control algorithm demands two controllers. One controller is designed such that the screw jack 1 and 2 follow the position reference signal generated by a tilt sensor. The other controller of two degree of freedom is designed to remove the synchronous error occurred between jack 1 and jack 2. The simulation results show that the desirable control performance is achieved.

• Journal of Power System Engineering
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• v.11 no.1
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• pp.134-139
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• 2007

A delivery ship is used to handle the cargo with the crane to/from the ships. The ship is inclined in the direction of a cargo which is hung on a crane. In this case, a arc shaped rail should be in the equilibrium state to get good anti-rolling performance. In this study, a device and control algorithm are developed to take accurate and quick equilibrium of the rail. The device is composed of a hinged immovable support, screw jack and damper. And the control system is based on I-PD control law to consider of control input saturation and overshoot. The controller is composed of integral controller of feedforward path and proportional-derivative controller of feedback path. The parameters of controller is designed to follow the reference signal and to remove overshoot. The simulation results show that the desirable control performance is achieved.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.697-702
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• 1998

방사선에 의해 유발되는 난소내 난포의 폐쇄가 apoptosis를 매개로 하여 일어나는지 조사하고자 면역조직화학적 방법을 이용하여 실험을 수행하였다. 미성숙 생쥐 (3주, ICR)에 감마선을 조사하였으며, 조직절편을 제작한 후 TUNEL 방법에 의한 in situ 3'end labelling 면역조직화학 염색을 실시하였다. 전반적인 난소의 상태를 파악하고자, 일반적인 hematoxylin-eosin(HE) 염색을 실시하여 대조하였다. 면역조직화학 염색은 apoptosis가 일어난 난포를 시각적으로 구분해낼 수 있는 효과적인 방법임이 실험적으로 확인되었다. ApopTeg/HE 비율을 볼 때, R군은 6h에서 12h 에 높은 값을 보였고, 8d군에서 다시 증가하는 양상을 보였으며 이같은 결과는 실험동물의 난소내 과립세포의 apoptosis가 방사선 조사후 6시간부터 일어나기 시작하여 점차 증가된다는 사실을 나타낸 것이다. 결론적으로 방사선에 의한 난포의 폐쇄는 과립세포의 apoptosis를 매개로 하여 일어남을 알았다.

• Clinical and Experimental Reproductive Medicine
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• v.33 no.1
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• pp.35-35
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• 2006

Objective: The purposes of the present study were to investigate the effect of ${\gamma}$-radiation on the expression of inhibin-${\alpha}$ proteins and genes for inhibin ${\alpha}$, ${\beta}A$, and ${\beta}B$ in the ovary. Methods: Immature mice were whole-body ${\gamma}$-irradiated with 25% of a lethal dose. At time 0, 3, 6, 12, and 24 hours after the irradiation, the ovaries were collected and used for immunohistochemistry for inhibin-${\alpha}$, and RT_PCR for inhibin-${\alpha}$, ${\beta}A$, and ${\beta}B$. Results: The expression of the immunoreactive inhibins-${\alpha}$ was maintained at 12 hours post-irradiation and reduced thereafter. The expression of inhibin-${\alpha}$ mRNA was significantly increased with the time after the irradiation. However there were no significant changes in the expression of ${\beta}A$ and ${\beta}B$ mRNAs. Conclusion: It might be thought that inhibin acts as one of the regulatory factors in the ${\gamma}$-radiation-induced follicular atresia in mice

• The Korean Journal of Zoology
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• v.33 no.2
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• pp.152-157
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• 1990

The present study, using immunohistochemical procedure, was carried out to determine the localization of immunostainable $\beta$-endorphin cells in the mouse ovarian tissues. Mature female mice were perfused with 4% neutral buffered paraformaldehyde under anesthesia and then frozen-sections were immunostained with anti $\beta$-endorphin antiserum according to ABC technique. Immunoreactive $\beta$-endorphin was found in the luteal cells of corpus lutea, but not in the thecal cells. More strong immunostaining signak were observed in large corpus luteum, in particular, the regressing luteal cells. Primary and secondary follicles did not show any immunoreactivity of $\beta$-endorphin, but granulosa cells lining the antral cavity of large antral follicles contained immunoreactive $\beta$-endorphin.

• Journal of Radiation Protection and Research
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• v.19 no.3
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• pp.179-188
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• 1994

Mice were whole body irradiated with dose of 2.88Gy and 7.2Gy(Co-60) in order to observe the morphological and functional changes in radio sensitive mouse ovary. Microtechnical sectionates of $7{\mu}m$ thickness from ovary were made for light microscopy and concentrations of progesterone, testosterone and estradiol in ovarian homogenates were analyzed by radioimmunoassay. Gamma radiation resulted in the increase of atretic ratio of preantral and antral follicles, the increase of progesterone concentration in ovarian homogenates, and the low level of testosterone and estradiol. It is suggested that radiation protect the activity of $3{\beta}-HSD$(hydroxysteroid dehydrogenase) and isomerase in the follicular theca cell followed by low level of testosterone and estradiol and thereafter follicular atresia proceed.

• Development and Reproduction
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• v.12 no.3
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• pp.251-259
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• 2008

The plasticizer di(2-ethylhexyl)phthalate(DEHP) is one of the most well known endocrine disrupting chemicals (EDCs) because of its strong anti-androgenic effects on the reproductive and developmental process in male rodents and human. The present study was performed to examine whether prepubertal exposure to DEHP can make any alteration during the maturation of accessory sex organs in male rats. As a result, there was no significant change in body weights, serum T levels and tissue weights except of seminal vesicle and ventral prostate in DEHP-treated animals compared to vehicle-treated ones. The seminal vesicle weights in high-dose group (200 mg/kg) were significantly lower than those from the control group (p<0.05), and ventral prostate weights were significantly lower than those from the control group (p<0.05) in both low-dose (20 mg/kg) and high-dose group. Histological studies revealed that the seminal vesicles from DEHP-treated groups showed reduced areas of mucosal folds. Pseudostratified columnar epithelia were observed in the ventral prostates of DEHP-treated samples while cuboidal epithelia were found in the control group. The transcriptional activities of ER-$\alpha$ in seminal vesicle from high-dose group (p<0.05) were significantly higher than those from the control group, and ER-$\beta$ expression was significantly decreased in low-dose group (p<0.05) compared to the control. In ventral prostate, ER-$\beta$ mRNA levels from low-dose group (p<0.05) were significantly lower than those from the control group, and significantly increased in high-dose group (p<0.01). AR expressions, however, were not significantly different in all experimental groups of both seminal vesicle and ventral prostate. In conclusion, the present study demonstrated that (i) adverse effect (s) of DEHP on sexual maturation during prepubertal period could be limited, (ii) seminal vesicle and prostate gland were sensitive targets to DEHP in prepubertal rats and (iii) the deleterious effects of DEHP might be mediated through ER-associated mechanism.

• Journal of Radiation Protection and Research
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• v.23 no.2
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• pp.89-96
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• 1998

To assess the radioprotective effects of follicle stimulating hormone (FSH) on ovarian follicles, 3 week-old female mice were irradiated with 8.33 Gy of ${\gamma}$-ray (group R) and followed by 5 IU ip-injection of FSH (group RF). For control groups, 5 IU of saline (group C) or 5 IU of FSH (group F) was ip-injected. Ovaries were collected 0h, 6h, 12h, 14, 2d, 4d, and 8d after irradiation or saline/FSH injection, and followed by fixation in neutral buffered formalin for routine histochemistry. Immunohistochemistry was used to assess the status of follicles and DNA fragmentation was analyzed by agarose gel electrophoresis for total DNA. Staining specific for apoptotic follicles showed high intensity at 6h and 12h in group R and RF On the other hand, staining specific for proliferating follicles showed noticeably high intensity at 8d in group R and Rf. DNA fragmentation of 185bp increased with time in all experimental groups. Especially 370bp appeared at 6h in group R, then disappeared after 1d. In case of group RF, it appeared at 12h and disappeared after 1d. From the above results, the irradiated antral follicles become completely disappeared from 4d to 8d, and then new follicles started to grow again at 8d. FSH had delaying or suppressing effects on follicular atresia after irradiation. In addition, it became clear that radiation-induced follicular atresia was mediated by granulosa cell apoptosis.