• Current Research on Agriculture and Life Sciences
• /
• v.8
• /
• pp.45-50
• /
• 1990

This study was carried out ot investigate the effects of fetal calf serum (FCS) and gonadotropins supplemented to the medium on maturation and fertilization in vitro of porcine follcular oocytes. Ovaries were obtained from gilts at local slaughter-house. Oocyte-cumulus complexes were recovered by puncturing the ovarian follicles(3~5 mm in diameter). The complexes from individual ovaries were pooled in a $0.4m{\ell}$ droplet of medium covered with paraffin oil, then washed twice in fresh droplet and cultured for 36hrs in culture media according to experimental conditions. Boar epididymal spermatozoa were capacitated by preincubation for 4hrs in m-KRB medium and the preincubated spermatozoa were insemenated in the fertilization medium containing the cultured oocytes. The results obtained in this study are summarized as follows: 1. The maturation rates of oocytes cultured in m-KRB and m-KRB supplemented to 10% FCS were 82 and 37%, respectively. When PMSG, hCG. and PMSGt hcG($10Iu/m{\ell}$) were added to the media supplemented to 10% FCS, the maturation rates were 66, 58 and 68%, respectively. 2. Expansion of cumulus cells was not occured in m-KRB and m-KRB supplemented to 10% FCS. However, when PMSG, hCG and PMSG+hCG($10Iu/m{\ell}$) were added to m-KRB supplemented to 10% FCS, the expansion rates of cumulus cell layers were 92, 13 and 91%, respectively. 3. When oocytes were mltured in m-KRB, the rates of penetration and formation of male pronucle: were 93 and 7%, respectively. By adding FCS and gonadotropin to m-KRB, the penetration and formation of male pronuclei were 100 80%, respectively.

• Journal of Embryo Transfer
• /
• v.21 no.2
• /
• pp.137-146
• /
• 2006

The objective of this study was to examine the effect of donor cell types, the source of recipient oocytes and estrous synchronization on pregnancy and delivery rates of somatic cell nuclear transfer (SCNT) embryos in Korean native goats. Recipient oocytes were surgically collected after superovulation. Ear cells and fetal fibroblasts were collected and cultured in serum-starvation condition (TCM-199 + 0.5% FBS) for cell confluence. The zonae pellucidae of in vivo- and in vitro-matured oocytes were partially drilled using a laser system. Single somatic cell was transferred into the enucleated oocyte. The reconstructed oocytes were electrically fused with 0.3 M mannitol. After the fusion, embryos were activated by Ionomycin+6-DMAP. NT embryos were cultured in mSOF medium supplemented with 0.8% BSA at $39^{\circ}C$ in an atmosphere of 5% $CO_2$, 5% $O_2$, 90% $N_2$ for 12 to 20 hr. One hundred and two SCNT embryos were transferred into 20 recipients and pregnancy rate at days 30 was 20.0%. Of them, one developed to term and delivered 1 kid. Ear cells showed significantly higher fusion (63.8 vs. 26.5%) and pregnancy rates (20.0 vs. 0.0%) than those of fetal fibroblast (p<0.05). The recipients synchronized by CIDR showed significantly lower pregnancy rates compared to that of recipient in natural estrus ($0.0{\sim}25.0%$ vs. 100%) (p<0.05). Cloned kid was born from the recipient in natural estrus. For the synchronization of estrus between recipient and donor, there was no difference between treatments (${\pm}0$ vs. +12 hr) in pregnancy rate. The first healthy cloned kid (Jinsoonny) was produced by transfer of SCNT embryos derived from in vivo oocytes and ear cells into a recipient goat whose estrus was synchronized with the donor. These results imply that donor cells for nuclear transfer may affect the success rate, and the estrus synchronization between donor and recipient animals can also be important.

• Korean Journal of Ichthyology
• /
• v.29 no.4
• /
• pp.261-266
• /
• 2017

Microphysogobio koreensis is an endemic Korean freshwater fish that is protected as an endangered fish by the Ministry of Environment in Korea. In this study, we attempted to investigate the spawning period and spawning characteristics of M. koreensis to obtain basic information for its conservation. Though natural and histological observation, the spawning season occurred between April and May, with peak spawning occurred in early May when the water temperature was $20{\sim}23^{\circ}C$. During the spawning season, males had a bright-orange body and a thick red horizontal line from the rear of the operculum to the caudal peduncle, along with a lateral line, while females had a dark brown body. Nuptial organ had not appeared. The number of eggs in the ovaries was 10,705~22,165 ($15,573{\pm}4,274$). The number and appearance ratio of mature eggs were 1,100~5,920 ($3,383{\pm}2,126$) and 10.3~44.8% ($22.4{\pm}15.6$), respectively. And the size of mature eggs was 0.60~1.00 mm ($0.74{\pm}0.06$).

• Journal of Information Technology and Architecture
• /
• v.9 no.2
• /
• pp.155-166
• /
• 2012

Recently EA(Enterprise Architecture) has been receiving growing attentions again from the public sectors. It is because EA maturity result is reflected to the organization's informatization level and EA maturity ratio has been enlarged. There has been more participation from the Chief Information Officers of the public sectors. EA research in the public sectors has influenced IT environment since the research started in late '90, the legislation work done in '05, and the maturity model developed in '06. However, there are some remaining tasks to solve. EA policy is introduction oriented, its contribution to the consecutive the best UN e-Government rank is limited, and its user-friendly responding system is still lacking. Related research outcomes are rather microscopic focusing only on the models and maturity than implicating on the public policy in a macroscopic manner. In this respect, this study will provide the implication on how EA policy should be. Requirements derived from EA stakeholders and the tasks will be arranged in accordance with its domain, then the performance and tasks will be demonstrated. As guiding EA stake holders and information related officers to setup the EA policy with these results, this study is expected to support information the policy drivers.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.29 no.1
• /
• pp.115-123
• /
• 1996

For ecological study of Synechogobius hasta the environmental factors, length composition, stages of ovarian maturation, growth, and stomach contents of this species were examined. The samples were collected from the Kum River estuary from May, 1994 to June, 1995. The ovarian egg development of this species underwent 4 stages : the oogonium stage in October to November, growth stage in December to February of next year, maturity stage in February to April, and spawning stage in late April to middle May. The peak spawning period appeared in early to middle May. The fecundity varied from 8,600 to 49,000 showing a exponential increase by body size. The minimum size having matured eggs was 225 mm in total length (standard length 180 mm). The larvae smaller than 10 mm appeared in late May, and young fish of total length $13\~15mm$ entered into bottom life in the shallow waters. The young fish grew rapidly and reached about 141.7 mm in late October. The fish inhabited in the subtidal zone from December to May of next year when began to spawn. The largest specimen examined in this study was 531 mm of male, 472 mm of female. The major food items of young fishes were copepods and invertebrate larvae, and those of adult fishes were crabs, fish, shrimps, cephalopods, and polychaetes.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.7
• /
• pp.1016-1027
• /
• 2015

This study collected 120 figs, classified them into six degrees of maturity according to hardness values, and analyzed contents of organic acids and free sugars. Volatile compounds in figs were investigated using the solid-phase microextraction method of gas chromatography/mass spectrometry. For measurement of texture, elasticity increased up to stage 4 and decreased again. Cohesiveness and brittleness increased with maturation. Organic acids in figs were mainly composed of citric acid, malic acid, and tartaric acid in the final stage. Fructose and glucose were the major sugar components of figs. Fructose content decreased from stage 1 to stage 4 and then increased significantly. One hundred and nineteen volatile compounds were identified in figs, and classes were 14 acids, 15 alcohols, 23 aldehydes, 10 esters, 33 hydrocarbons, 11 ketones, four aromatics, six miscellaneous, and five terpenes. The dominant volatile components in figs were hexadecanoic acid, hexane, dodecanal, DL-limonene, 2-hexanal, nonanal, and 6-methyl-5-hepten-2-one.

• Journal of Korean Society of Forest Science
• /
• v.85 no.4
• /
• pp.656-666
• /
• 1996

Aspen demand has increased recently in the Great Lakes region in the United States. Since aspen has moved into the region in late 1800's, its growing stock has increased so as to change forestry industry of the Lake States. Intensive timber harvesting and biomass removal may cause nutrient depletion, especially on nutrient-poor sites. Forest nutrients and nutrient cycling were investigated in aspen stands of 7-10, 27-33, and 41-42 year-old growing on sandy soils in Minnesota. Nutrients added to the aspen stands by atmospheric deposition and soil weathering were efficiently absorbed and stored in the tree biomass. Aboveground biomass increased from $24.4t{\cdot}ha^{-1}$ at young stands to $139.2t{\cdot}ha^{-1}$ at mature stands. Nutrients accumulated in the tree biomass showed same magnitude of difference. Nutrients added to the site through atmospheric deposition were in the order of Ca, N, K, Mg, and P. Annual litterfall was greater in older stands. However, the amount of nutrients returned by litterfall was not significantly different among stand ages due to the greater nutrient contents in the litterfall of young stands. Litter decomposition and nutrient release rates were greater at young stands than at older stands. Likewise, nutrient availability was higher in young aspen stands and became lower as the stands grew older. Nutrient leaching loss was minimal at all stand ages. Soil N mineralization was greater at young stands than at older stands. Nutrient cycling process was facilitated in young aspen stands with an increased level of available nutrients, Based on the estimations of nutrient balance and nutrient removal by harvesting, Ca was the most critical element which was likely to be depleted if aspen stands are intensively harvested with short rotations.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2018.04a
• /
• pp.42-42
• /
• 2018

메밀은 마디풀과(polygonaceae)의 메밀속에 속하는 일년생 초본으로 야생종을 포함하여 20여 종이 확인되고 있다. 현재 재배되고 있는 메밀 재배종은 보통메밀(Fagopyrum esculentum Moench)과 쓴메밀(Fagopyrum tataricum Gaertn., 타타리메밀) 등 두 종이 주류를 이루고 있으며 우리나라에서는 보통메밀이 주로 재배되어 왔다. 본 연구는 농업유전자원센터에서 보유중인 보통메밀 341점과 쓴메밀 38점을 봄, 여름에 파종하여 특성조사를 수행하고 재배시기별 생육특성을 비교하기 위해 수행되었다. 봄, 여름 파종은 각각 2017년 4월 14일과 8월 17일에 전주 소재 농업유전자원센터 포장에 하였으며 줄기색, 엽색, 엽형, 개화기, 성숙기, 꽃색, 종피색, 종자모양, 주경절수, 총분지수, 백립중 등 11개 농업형질을 조사하였다. 봄 파종시 개화기는 대부분 5월 25일 전후였으며 성숙기는 6월 말부터 7월 중순까지 분포하였고 여름 파종시는 9월 15일 전후 개화하여 10월 말에 성숙하였다. 줄기색은 홍색의 비율이 높았고 엽색은 연녹색과 녹색이 대부분이었으며 엽형은 화살촉형이 90% 이상이었다. 꽃색은 흰색이 대부분이었지만 연녹색 자원도 40점 조사되었으며 종피색은 연갈색이 70%를 차지하였다. 종자 생산과 관련된 주경절수와 총분지수는 봄 파종과 여름 파종에서 많은 차이를 나타냈으며 봄 재배시 영양생장이 왕성하여 가을 재배보다 많은 주경절수와 총분지수가 조사되었다. 그러나 백립중에서는 여름 파종이 봄 파종보다 무거운 경향을 나타내어 주경절수, 총분지수와 백립중 간 부의 상관관계를 추론할 수 있었다. 일반메밀 유전자원을 국내 수집지별로 나누어 조사한 결과 주경절수와 총분지수는 봄, 여름 파종 모두에서 전남 수집자원이 가장 많았으며, 강원, 경남, 경북, 전북, 충북 수집자원과 유의성있는 차이를 나타내었다. 강원, 충북 수집자원은 제일 낮은 주경절수와 총분지수를 보였으나 백립중은 가장 높게 조사되었다.

• Korean Journal of Food Science and Technology
• /
• v.31 no.6
• /
• pp.1503-1510
• /
• 1999

This study was performed to investigate the physicochemical properties of Korean Citrus sudachi fruit which were harvested at different harvesting time(every 20 days from Sep. 3 to Nov. 8) and region(Seogwipo and Cheju city area). The average weight of Citrus sudachi fruit harvested from Seogwipo area was as twice as that of Cheju area at the same period. The moisture content in fruit peel increased by ripening of fruit, but that of fruit juice showed no difference. The content of reducing sugar in fruit peel and fruit juice increased 2 times from Sep. 3 to Nov. 8. The content of crude fiber decreased both in fruit peel and fruit juice as progression of ripening. Crude protein and ash contents decreased in fruit peel but revealed no differences in the fruit juice during the same period. pH decreased in fruit peel and juice with its ripening. The content of vitamin C decreased by ripening of fruit. The transmittance which is important quality factor in fruit juice increased from Sep. 20 to Oct. 13. The content of free sugar increased about 2 times in fruit peel from Sep. 3 to Nov. 8 and showed 4 times increase in fruit juice at the same period. In the composition ratio of mineral, Ca and K were abundant in the fruit peel, but only K was the most abundant mineral in fruit juice than any others.

• Korean Journal of Environment and Ecology
• /
• v.35 no.3
• /
• pp.277-284
• /
• 2021

This study surveyed the ecological characteristics of Squalidus gracilis majimae at Nakdong River tributary Sinan Stream from January to December 2020. The species inhabited the riverbed that was mostly covered with gravel and sand. The water depth was 27-158 cm, and the average was rather deep at 54 cm. The stream velocity was slow at 0.41±0.19 (0.24-0.86) m/sec. The gender ratio of females to males was 1:0.73. According to the total length-frequency distribution, the age indicated that the group with less than 50 mm in total length was one year old, the group with 70-69 mm was two years old, and the group over 70 mm was three years old. The total length of sexually mature fishes was 50 mm for females and 60 mm for males. The spawning season was from June to July, and the water temperature was 20.9-23.4℃ during the period. The prosperous spawning season was July. The average number of eggs in the ovaries was 1,009 (595-1,630) per matured female, and the matured eggs were yellowish and spherical with a mean diameter of 0.78±0.08 (0.57-0.83) mm. The live foods were S. gracilis majimae Protozoa, attached algae, zooplankton, and aquatic insects. The feeding habits of S. gracilis majimae are omnivorous, but more than 80% of the stomach content was aquatic insects, Chironomidae spp. The larger the size of this species, the greater the amount and frequency of eating aquatic insects, which are animal feeds. The population that ate aquatic insects did not eat vegetable food.