• Parasites, Hosts and Diseases
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• v.29 no.3
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• pp.245-258
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• 1991

In order to determine the antigenic localization in the tissues of the adult Metagonimus yokegawai, immunogoldlabeling method was applied using serum immunoglobulins (IgG) of cats which were infected with isolated metacercariae from Plecoglossus altivelis. The sectioned worm tissue was embedded in Lowicryl HM 20 medium and stained with infected serum IgG and protein A gold complex (particle size: 12 nm) , It was observed by electron microscopy at each tissue of the worm. The gold particles were observed on the tegumental syncytium as well as cytoplasm of tegumental cells and epithelial lamella of the caecum. The gold particles were not observed on the basal lamina of the tegument, interstitial matrix of the parenchyma, the muscle tissue and mitochondria of the tegument. The gold particles were specifically labeled in the secretory granules in the vitelline cells. They were also labeled on the lumen of bladder and egg shell. The above findings showed that antigenic materials in the tissue of adult worms were specifically concentrated on the tegumental syncytium as well as cytoplasm of tegumental cells and epithelial lamella of the caecum.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.533-540
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• 2000

Gonadal development, gametogenesis, reproductive cycle, gonad index, flesh weight rate, and first sexual maturity of the turban shell, Lunella coronata coreensis were investigated by histological observation. The materials used were collected monthly from the rocky intertidal zone of Daehang-ri, Buan-gun, Jeollabuk-do, on the west coast of Korea, from July 1998 to June 1999. Sex of L coronata coreensis was separate. The gonad was widely located in the spirals of the visceral mass buried in the digestive gland. The ovary and testis were composed of a number of oogenic follicles and speymatogenic follicles, respectively. Monthly variations in the gonad index increased from March ($23.86{\pm}3.73$) when the water temperature increased and reached the maximun in July ($49.76{\pm}6.47$). And then, the gonad index sharply decreased in September ($15.58{\pm}2.33$). The flesh weight rate ranged from $25.2{\%}$ to $32.3{\%}$, and its variation showed a similar pattern to the gonad index. Individuals $<5.9 mm$ in shell height could not take part in reproduction in both sexes. Percentages of first sexual maturity of female and male specimens ranging from $7.0{\~}7.9 mm$ in shell heights were $84.6{\%}\;and\;91.7{\%}$, respectively, and $100{\%}$ in those over 8.0 mm in shell height in both sexes took part in reproduction. By studying the monthly changes of the morphological features and sizes of germ cells during gametogenesis in the gonad, the reproductive cycle of this species could be devided into five successive stages: early active (December to April), late active (January to July), ripe (May to August), spawning (July to September), and recovery (September to March). The spawning period of this species was once a year between July and September, and the main spawning occurred in July when the seawater temperature reached above $24.8^{\circ}C$. The fully ripe eggs were $150{\~}160\;{\mu}m$ in diameter.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.3
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• pp.263-274
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• 2020

In the Southeast Sea of Korea, a cold water mass is formed intensively in summer every year, causing frequent abnormal sea conditions. In order to analyze the spatial changes of sea surface temperature distribution in this area, ocean fields buoy data observed at Gori and Jeongja and reanalyzed sea surface temperature(SST) data from GHRSST Level 4 were used from June to September 2018. The buoy data were used to analyze the time-series water temperature changes at two stations, and the GHRSST data were used to calculate the daily SST variance and weighted mean center(WMC) across the study area. When the buoy's water temperature was lowered, the variance of SST in the study area trend to increase, but it did not appear consistently for the entire period. This is because GHRSST is a reanalysis data that does not reflect sensitive changes in water temperature along the coast. As such, there is a limit to grasping the local small-scale water temperature change in the coast or detecting the location and extent of the cold water zone only by the statistical variance representing the SST change in the entire sea area. Therefore, as a result of using WMC to quantitatively determine the spatial location of the cold water mass, when the cold water zone occurred, WMC was located in the northwest sea area from the mean center(MC) of the study area. This means that it is possible to quantitatively identify where and to what extent the distribution of cold surface water temperature appears through SST's WMC location information, and we could see the possibility of WMC's use in detecting the scale of cold water zones and the extent of regional spread in the future.

• Development and Reproduction
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• v.4 no.2
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• pp.195-201
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• 2000

Sex differentiation process of the spotted sea bass, Lateolabrax maculatus, was investigated by histological method. The fish samples were collected from just after hatching to 365 days later. The primordial germ cells and genital ridge were appeared separately hanging under air bladder in 30-day larva (total length: 11.7~13.2 mm), and were unified into the undifferentiated gonads in 40-day larva (12.5~14.0 mm). The ovarian differentiation was started in 60-day juvenile (23.6~27.0 mm). The somatic tissues were elongated in tip of both ends of undifferentiated gonad and were fused each other. The complete ovarian cavity was appeared in 80-days juvenile(33.1~42.5 mm). The testicular differentiation was initiated in 70-day juvenile (24.8~31.6 mm). The rudiment of sperm duct was appeared in the center of the undifferentiated gonad. The meiosis of germ cells in the ovary was started in 168-day juvenile (88.0~115.4 mm). In 287-day juvenile (175.1~233.6 mm), the ovary was filled with both of chromatin stage and perinucleolus stage oocytes. The meiosis of male germ cells was started in 245-day juvenile (124.4~168.3 mm). However, the seminiferous tubules of testis were filled with numerous sperm in 365-day juvenile (162.5~253.8 mm). The sex ratio of male and female was 1:1.38. Considering these results, the spotted sea bass was showed differentiated type in sex differentiation and gonochorism in sexuality.

• Journal of Embryo Transfer
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• v.16 no.3
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• pp.163-172
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• 2001

The present study was carried out to examine the effects of $O_2$concentrations and culture media on in vitro maturation and embryo development of porcine follicular oocytes. The results were summarized as fellows : 1. The rates of GVBD and nuclear maturation in NCSU-23 and TCM-199 media with 10% PFF under the conditions of 5% and/or 20% $O_2$concentrations were not different among the each treatment groups(P>0.05). 2. The rates of polyspermy and mean numbers of penetrated sperm were significantly lower in NCSU-23 medium than in TCM-199 medium (P>0.05). However, the rates of polyspermy and mean numbers of penetrated sperm were not different between 5% and 20% $O_2$concentrations. 3. The rates of blastocyst formation at day 7 after in vitro fertilization were significantly higher in NCSU-23 medium under the condition of 20% $O_2$concentration than in TCM-l99 medium under the condition of 5% or 20% $O_2$concentrations. However, the rates of blastocyst formation and total cell numbers in blastocysts were not different between 5% and 20% $O_2$concentrations. In conclusion, the use of NCSU-23 medium under the condition of 20% $O_2$concentration was beneficial for porcine oocyte maturation and in vitro development.

• Reproductive and Developmental Biology
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• v.28 no.3
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• pp.173-179
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• 2004

This study was conducted to investigate the toxi-cological effects of different vitrification solution on development of immature porcine oocytes in vitro. Oocytes were exposed to EFS solution [40% ethylene glycol (EG) + 18% Ficoll + 0.3M sucrose], ES solution (5.5M EG + 1.0M sucrose) or GE solution [10% glycol (G) + 20% EG], and these oocytes were transferred to sucrose solution directly. Maturation rates were significantly (P<0.05) higher in the ES solution (44.5%) and control (57.6%) than in the EFS solution (38.8%) and GE solution (22.4%). No differences among three solution were found in fertilization rates. Cleavage rates was significantly (P<0.05) higher in the ES solution (47.1%) and control (65.9%) than in the EFS solution (21.9%) and GE solution (19.0%), but no difference among three solutions was found in the blastocyst formation rates. These results indicate that combination of EG and sucrose solutions had effects on development of immature porcine oocytes.

• Korean Journal of Animal Reproduction
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• v.20 no.2
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• pp.127-134
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• 1996

The objective of this experiment was to test the ability of the fertilization of EGF treated pig oocytes for in vitro maturation. The addition of EGF (10 ng/ml), FSH (10 ${\mu}\textrm{g}$/ml), or FBS (10%) on maturation medium of pig immature oocytes divided into four groups as follows; group 1: untreatment, group 2: EGF alone, group 3: combination of FSH and FBS, or group 4: combination of EGF, FSH, and FBS. The interactive effects of nuclear maturation rates (M II%) of EGF alone, FSH plus FBS, and EGF plus FSH added FBS treatments were significantly higher than those of non-treatments (P<0.001). The fertilization rate of EGF alone (group 2) was lower than that of 3, 4 groups, but was significantly higher than group 1 (p< 0.005). Furthermore, combination of EGF, FSH,and FBS (group 4) was higher than others (group 1. 2, 3) on male pronuclei formation as well as penetration of sperm (P<0.05). These results suggested that EGF alone decreased the ability of cytoplasmic maturation compared to nuclear maturation in pig oocytes, but a high level of cytoplasmic maturation of in vitro-matured pig oocytes can be achieved when supplemented with FSH and FBS.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.86-86
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• 2002

면양과 염소가 최근 수십년동안 세계여러 나라에서 번식생리의 연구를 위한 모델로 사용되어 왔는데, 체내수정란의 생산에 관한 영역도 유럽을 중심으로 활발하게 연구되어왔다. 수정란생산을 위한 발정동기화방법, 과배란처리 및 수정란회수방법 기술은 현재 상당히 많은 기술진척이 이루어진 상태이나, 우리나라 고유의 재래유전자원인 흑염소에는 이를 위한 기술이 미진한 실정이므로 본 실험에서는 흑염소의 체내수정란생산기술을 확립하여 재래가축 유전자원보존을 위한 기초기술을 마련하고자 한다. 축산기술연구소 남원지소에서 사육하고 있는 체중 20kg 이상의 건강한 흑염소를 이용하여 발정동기화를 위해 controlled intravaginal drug release(CIDR)를 질내에 14일 동안 삽입하고, 과배란처리는 FSH를 CIDR 삽입 12, 13, 14일째에 12시간 간격으로 점감법으로 총20mg을 투여하였으며, PGF$_2$a를 13일째 FSH와 함께 투여하였다. CIDR는 14일째의 아침에 제거하였다. 수컷과의 교미는 CIDR제거 24시간후에 GnRH를 투여와 동시에 실시하였으며, 채란은 교미후 3일째에 외과적인 방법으로 실시하였다. CIDR처리경과에 따른 progesterone농도는 CIDR 주입시 바로 수치가 상승하여 제거전까지 6~12ng/m1의 농도를 유지하였으며, 제거즉시 2ng/ml 이하로 떨어졌다. 채란시 평균 배란점은 16.5개, 미배란난포 9.8개였으며, 회수수정란은 6.0개를 나타내어 채란율은 36.4%를 나타내었다. 회수된 수정란의 발달단계는 4-cell 78.9%, 2-cell 5.3%, fragmentation 15.8%를 나타내었다. 이와 같은 체내수정란생산방법을 기반으로 하여 이후 수정란의 동결 및 수정란이식기법에 관한 연구를 수행한다면 우리나라의 재래가축인 흑염소의 유전자원 장기보존과 생산성향상에 기여할 것으로 사료된다.배양액에 30 embryos/50ul 소적으로하여 38.8$^{\circ}C$, 5% $CO_2$의 탄산가스 배양기에서 각각 7일간 배양을 실시하였다. 조사된 결과는 SAS/STAT를 이용하여 통계분석을 실시하였다. 체외수정 12시간 후에 난자 급속 염색법으로 염색을 실시한 결과, 모든 처리구에서 핵성숙률(76.4~95.2%), 정자침투율(51.1~66.9%), 웅성전핵형성률(95.2~100%), 다정자침입률(18.2~25.6%) 및 평균침입정자수(1.2~l.4개)에서 유의적인 차이가 인정되지 않았다. 체외배양 48시간 난할률을 조사한 결과, 처리구별 차이(53.9~67.9%)는 인정되지 않았으나, 배양 7일째 배반포형성률은 각각 14.5, 25.4, 17.3 및 12.4%로서 25uM의 $\beta$-ME처리구가 유의적(P<0.05)으로 높은 배발달률을 나타내었고, 총세포수에 있어서는 대조구와 처리구간 유의적인 차이가 인정되지 않았다. 따라서 돼지 난포란을 성숙배양할 때, 25uM $\beta$-ME를 첨가배양하는 것이 양질의 돼지체외수정란을 생산하는 하나의 방법으로 조사되었다.다.natural objects and was popular at the time of Yukjo Dynasty, and there are some documents of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to have been "Japanese Letter Jobcheso." Therefore, the purpose of this study is to look into the origin

• Journal of the Microelectronics and Packaging Society
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• v.13 no.3 s.40
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• pp.1-8
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• 2006

Higher density integration and adoption of new materials in advanced electronic package systems result in severe electrochemical reliability issues in microelectronic packaging due to higher electric field under high temperature and humidity conditions. Under these harsh conditions, metal interconnects respond to applied voltages by electrochemical ionization and conductive filament formation, which leads to short-circuit failure of the electronic package. In this work, in-situ water drop test and evaluation of corrosion characteristics for SnPb solder alloys in D.I. water and NaCl solutions were carried out to understand the fundamental electrochemical migration characteristics and to correlate each other. It was revealed that electrochemical migration behavior of SnPb solder alloys was closely related to the corrosion characteristics, and Pb was primarily ionized in both D.I. water and $Cl^{-}$ solutions. The quality of passive film formed at film surface seems to be critical not only for corrosion resistance but also for ECM resistance of solder alloys.

• Journal of the Korean Magnetics Society
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• v.10 no.1
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• pp.37-41
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• 2000

We investigated the magnetoresistance effect and the exchange coupling of antiferromagnetic Fe$_2$O$_3$ spin-valve film. The X-ray diffractions of the spin-valve films having a different thickness of a $\alpha$-Fe$_2$O$_3$ were measured. The exchange coupling field (H$_{ex}$) between Fe$_2$O$_3$ and pinned NiFe layer was increased from 13.5 Oe to 84.5 Oe, as the thickness of Fe$_2$O$_3$ increased from 400 $\AA$ to 800 $\AA$. The surface roughness of $\alpha$-Fe$_2$O$_3$spin-valves increased with the increase of $\alpha$-Fe$_2$O$_3$thickness. Therefore, the increase of H$_{ex}$ will be due to the increase of the interface roughness. The MR ratios as a function of Fe$_2$O$_3$ thickness was not changed. And H$_{ex}$ increased by the increment of magnetostatic coupling between Fe$_2$O$_3$ and NiFe (pinned-layer) due to the increment of interface roughness. H$_{ex}$ depends on the surface roughness, but the magnetoresistance ratio doesn't doesn't.