• Korean Journal of Animal Reproduction
• /
• v.20 no.2
• /
• pp.207-214
• /
• 1996

To examine the developmental capacity of manipulated embryos after ultrarapid refreezing and thawing, mouse embryos were biopsied at 4-cell stage, frozen twice at 4-cell and morula stages, respectively, and then transferred to rec-ipients. Single blastomeres were biopsied from 4-cell embryos by a modified aspiration method. Biopsied 4-cell embryos were equilibrated into freezing medium at room temperature for 2.5 min, loaded into 40 $\mu$I of freezing medium in 0.25 ml plastic straw and then directly immersed into liqiud nitrogen. Freezing medium for 4-cell embryos consisted of 4.0 M ethylene glycol and O.25 M sucrose in dPBS supplemented with 6 mg/lm BSA. Morulae were frozen into freezing medium containing 5.0 M glycerol instead of ethylene glycol. Thawing was conducted by agitating each straw in 3TC water for 20 sec. The c content of each straw was expelled into 0.5 ml of dilution medium, which consisted of 0.25 M sucrose and 3 mg/ml BSA in dPBS. The thawed embryos were rehydrated in dilution medium for 10 min, washed 3 times with dPBS and then cultured in M16 medium at 37$^{\circ}C$, 5% CO$_2$ in air. Blastocysts that developed from frozen or refrozne biopsied embryos were transferred to recipients on Day 3 of pseudopregnancy, respectively. In vitro and in vivo developmental rates of the biopsied and intact 4~cell embryos after freezing and thawing were 78 (10l/130) and 25% (10/40), and 91 (114/125) and 30% (12/40), respectively. Although the rates of in vitro development of biopsied and intact embryos to blastocyst stage were significantly different after freezing and thawing (P

• Journal of Embryo Transfer
• /
• v.19 no.3
• /
• pp.201-208
• /
• 2004

This study was performed to examine the effects of catalase and $\beta$-mercaptoethanol ($\beta$ME) on the establishment of clonal lines from porcine fetal fibroblast cells. Fibroblasts derived from a pig fetus (Day 50) were passaged two times before use. A single cell was seeded in 96-well plates and cultured in medium supplemented with or without catalase or $\beta$ ME. Cell colonies were passaged two times into 4-well dish. Cell lines with proliferating potential were classified as an established clonal cell line. In experience 1, the establishment efficiencies were examined by addition of catalase (100ng/$m\ell$) or $\beta$ME (100 uM) in culture medium. The establishment efficiency of $\beta$ME-added group (8.3％) was significantly higher than that of control group (3.2％, P<0.05). However, catalase did not have a positive efffct on the establishment efficiency. In experience 2, the establishment efficiencies were examined by addition of different concentrations of catalase (0-1,000 ng/$m\ell$) in culture medium. However, establishment efficiencies were not different among the different concentrations of catalase (0-2.6％). In experience 3. the establishment efficiencies were examined by addition of different concentrations of $\beta$ME(0-1,000 uM) in culture medium. The establishment efficiency was significantly higher in 100 uM $\beta$ME-added group (9.4％) compare to others (0-1.6％). The result of present study shows that the establishment efficiency of clonal cell lines can be enhanced by the culture in media supplemented with 100uM $\beta$ME. However, catalase did not have a positive effect on the establishment efficiency.

• Korean Journal of Animal Reproduction
• /
• v.26 no.1
• /
• pp.61-68
• /
• 2002

The present study was examined effects of aesculetin and $O_2$concentrations on in vitro development of Hanwoo (Korean Native Cattle) embryos derived from in-vitro matured and fertilized (IVM-lVF) oocytes. The oocytes were cultured for the first 40~44 h after in vitro fertilization, then embryos of 2 to 8 cell stages were cultured under the different culture conditions for another 6 days. In experiment 1, the higher rates of morulae and blastocysts were produced in 5% $O_2$, than in 20% $O_2$(P＜0.05). There was significantly (P＜0.05) higher in embryos cultured with 1 $\mu\textrm{g}$/$m\ell$ than with 0, 5 and 10 $\mu\textrm{g}$/$m\ell$ of aesculetin. In experiment 2, the proportions of embryo developed with blastocysts and morulae plus blastocysts in 5% $O_2$, again was significantly (P＜0.05) higher in 20% $O_2$, during the culture with aesculetin and/or taurine. In the 5 and 20% $O_2$atmosphere, the inclusion of 1 $\mu\textrm{g}$/$m\ell$ aesculetin or 2.5mM taurine increased significantly (P＜0.05) the percentages of blastocysts and morulae plus blastocysts. In experiment 3, in medium with aesculetin plus PDGF and taurine plus EGF than other treatment groups, significantly (P＜0.05) higher developmental rates were obtained. Number of blastomere in balstocyst stage were also higher in medium with that than without aesculetin. However, there were no significant differences in all culture conditions. In experiment 4, the proportions of embryo developed to the morulae and blastocyst stages were significantly (P＜0.05) higher rates in medium with natural and commercial aesculetin than in control medium. No significant differences, however, were observed in between natural (71%) and commercial (70.0%) aesculetin. Number of blastomere in blastocyst stage were also higher in medium with natural and commercial aesculetin than in control medium. However, there was no effect on the number of blastomeres by these treatment. These data indicate that preimplatation embryos are very sensitive to condition that can cause oxygen concentration and show that efficiency role of aesculetin for improving bovine embryo development in vitro.

• Childhood Kidney Diseases
• /
• v.11 no.2
• /
• pp.203-211
• /
• 2007

Purpose : We attempted to compare the independent factors such as age, sex, C-reactive protein(CRP), and white blood cell count(WBC) in children with radiologic studies and assess the necessity of performing voiding cystourethrography(VCUG). Method : 98 children who have been diagnosed their first time febrile urinary tract infection from Janurary 2002 to Januray 2005 were enrolled. In all patient, the duration of fever which occurred before and after treatment was recorded, and CRP, WBC, $^{99m}Tc$-2,3-dimercaptosuccinic acid($^{99m}Tc$-DMSA) renal scans, renal ultrasound and VCUG were analyzed. Results : Of the 98 children diagnosed with urinary tract infection(UTI), 52 were male and 46 were female. 18 had abnormalities in VCUG, 17 had abnormalities in kidney ultrasound, and 20 had partial defects or diffuse uptake decrease in $^{99m}Tc$-DMSA renal scans. There were no significant relationship between incidence of radiologic abnormalities and age. The risk of renal scar was significantly higher in children who had a longer febrile period before treatment than in those with shorter period. Both CRP and WBC were significantly elevated in children with the radiological abnormalities. A positive of $^{99m}Tc$-DMSA renal scans and renal ultrasound were highly associated with vesicoureteral reflux(VUR). Conclusion : If there are abnormalities in the kidney ultrasound and $^{99m}Tc$-DMSA renal scan of a child with initial UTI, a VCUG is recommended. Even in cases without abnormal findings in $^{99m}Tc$-DMSA renal scan and renal ultrasound, clinical data such as CRP and WBC should be assessed, and VCUG should be Performed for the undetected VUR.

• Journal of Bio-Environment Control
• /
• v.9 no.3
• /
• pp.166-170
• /
• 2000

Three methods for heat collection, which were the flat solar collector, two fan with radiator, and square pipe method, were studied to sue efficiently solar energy in the three different glasshouses for two years. The flat plate solar collector method was made use of the commercial solar collector with collection area of 24$m^2$, the method of two fans with radiators collected solar energy at the top of the glasshouse. An thermal storage tank was constructed underneath in teach glasshouses. When an area of 1,000$m^2$ was heated to the minimum temperature of 9$^{\circ}C$, the decrease rate of heating fuel for the flat plate solar collector, the fan attached radiator and the square pipe methods were 7%, 19% and 28% respectively. The flat plate solar collector method, which could be heated approximately 40-50$m^2$, was currently used by most of the farmer. Under the condition, the decrease rate of annual heating fuel was 14% which was not better for an economic annual heating fuel. If the fan with radiator method was operated, the use of installation and maintenance were required. So, it could not be good economic efficiency of solar heating. The heating efficiency of the square pipe method was relatively better thant those of the flat plate solar collector or the fan attached radiator. Since the cost of materials and its installation of the use of square pipe method was lower than any other method. However, corrosion of the pipe, greater shade in the greenhouse and strength against the square pipe were problems that should be overcome in the square pipe method.

• Korean Journal of Environment and Ecology
• /
• v.23 no.5
• /
• pp.447-459
• /
• 2009

This study is intended to provide basic date for the efficient management of Pinus densiflora community by analyzing ecological characteristics of Pinus densiflora inhabiting Byeonsanbando National Park. According to investigations, P. densiflora community and P. densiflora-Quercus community are widely distributed, occupying 40.3% of the total area. 21 sites ($400m^2$per site) are selected for TWINSPAN analysis, and the result indicates that the whole community of P. densiflora and P. densiflora-Quercus can be classified into 8 types, and the age of P. densiflora is 40-50 years, which is similar to that of deciduous broad-leaved trees. The 8 community types are: P. densiflora community which competes with Quercus variabilis; P. densiflora community in which Fraxinus sieboldiana and Quercus serrata grow in the understory layer; P. densifloa community in which Q. serrata grow in the understory layer and Smilax china var. microphylla in the shrub layer respectively; P. densifloa community in which P. densiflora and F. sieboldiana grow in the understory layer; P. densiflora community which competes with Q. serrata and Carpinus tschonoskii; P. densiflora community which competes with Q. variabilis and Q. serrata; P. densiflora community in which Prunus sargentii grow; P. densiflora community in which Abies holophylla grow. P. densiflora community which competes with Q. variablis and C. tschonoskii seems to be in a stage of succession to deciduous broad-leaved community. The analysis indicates that Shannon diversity index is 0.2756-1.3879. It also indicates that there is a negative correlation between P. densiflora and Q. variabilis and C. tschonoskii; there is a positive correlation between P. densiflora and F. sieboldiana and Rhododendron schlippenbachii. These investigations show that the transformation of vegetation is already under way. There is a possibility that ecological succession can take place in 30.4% of the total area from P. densiflora to Quercus and deciduous broad - leaved trees. Therefore, it is recommended that the preservation and maintenance of P. densiflora be implemented by taking control of competing species which undermine the stability of P. densiflora forest community.

• FLOWER RESEARCH JOURNAL
• /
• v.17 no.4
• /
• pp.279-284
• /
• 2009

In order to recover fertility from sterile interspecific OA-1 $F_1$ hybrid (Oriental hybrid 'Mero Star' ${\times}$ Asiatic hybrid 'Connecticut King'), various concentrations (0.1, 0.3 and 0.5%) of caffeine were injected directly into flower buds and then confirmed the viability of OA-1 $F_1$ hybrid at the flowering time. After the caffeine treatment, fertilized $F_1$ hybrids were crossed as female with Asiatic hybrid 'Lanzarote' as male. Five plantlets were obtained from seven embryos of 16 pollinated flowers at 0.3% treatment of caffeine while 0.5% treatment of caffeine obtained one plant let and 0.1 % treatment of caffeine plantlet did not produce at all. Thus 0.3% of caffeine treatment was considered as optimum concentration to produce subsequent progenies and the OA-l $F_1$ hybrid treated with caffeine produced 51% of putative 2n gametes. Pollen germination of OA-2 ('Romero Star' ${\times}$ 'Lady Rosa') and OA-3 ('Expression' ${\times}$ 'Lady Rosa') was not differ between temperature treatment alone and in combination with caffeine and temperature treatment. In the reciprocal crosses of OA-1 and Asiatic hybrid 'Lanzarote' or Oriental hybrid 'Sorbonne', A ('Lanzarote') ${\times}$ OA-1 or OA-1 ${\times}$ A crosses showed better results than O ('Sorbonne') ${\times}$ OA-1 or OA-1 ${\times}$ a crosses in plant obtaining. All progenies obtained from A ${\times}$ OA-1 or OA-1 ${\times}$ A crosses were confirmed as triploids by GISH analysis.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.27 no.3
• /
• pp.268-275
• /
• 1982

This study was conducted to obtain basic informations for breeding and improving cultural practices of sesame (Sesamum indicum L.) through investigation of several agronomic characters of 82 major varieties plants in April 20, May 15 and June 20. Stem diameter and plant height were largest in early planting(April 20). On the contrary, they were smallest in late planting(June 15). Therefore, the later planting, the poorer the vegetative growth on the basis of stem diameter and plant height. Number of capsules per plant and number of grains per capsule were 88 and 54, respectively, in the early planting, while they were decreased to 25 capsules and 40 grains in late planting. The percentage of ripeness and 1000 grain weight 78 and 2.3g in the April 20planting while they were 58% and 2.1g in June 20 planting indicating the later planting, the lower the ripeness. Grain yield per m1 in April 20 and June 20 planting was 112 and 18g respectively. Consequently, grain yield significantly decreased as planting delayed. On the basis of the vegetative and reproductive growth, varieties could be classified into early, conventional, late and indetermediate planting adapted groups. The major yield components were highly and postively correlated with accmulated sunshine hours and temperatures confirming that grain yield was closely related with sunshine and temperature. Among the varieties tested, Gurye and Local 135 had more than 150 capsules. Haenam and Woogang had more than 75 grains per capsule. Since grain yield oflate planted sesame were significantly different among the varieties, breeding of sesame for after barly cropping would be more effective under late cultural condition of after barly.

• Korean Journal of Animal Reproduction
• /
• v.25 no.1
• /
• pp.1-7
• /
• 2001

This study was to test whether in vitro matured Hanwoo oocytes can be successfully cryopreserved by a new vitrification procedure using MVC method. For the vitrification, oocytes were pretreated in 10% ethylene glycol (EG10) for 5~10 min, exposed in EG30 for 30 sec, each oocyte was individually put on the inner wall of 0.25 $m\ell$ straw, and then straws were directly plunged into L$N_2$. Thawing was taken by 4-step procedures 〔1.0 M sucrose (MS), 0.5 MS, 0.25 MS, and 0.125 MS〕 at 37$^{\circ}C$. In vitro developmental capacity (survival, cleavage ($\geq$2-cell) and blastocyst rates) in vitrified group was no significant difference compared to that in other treatment groups (exposed; 100.0, 74.4, 32.3% and control; 100.0, 78.3, 36.3%): high mean percentage of oocytes (91.2%) was survived, 69.4% of them were cleaved and 27.9% of cleaved embryos were developed to blastocyst. Especially, after transfer of in vitro developed embryos in vitrified group, four of six recipient animals were pregnant and three of them were ongoing-pregnant by manual palpation at 250 days after transfer. This result demonstrates that MVC method is very appropriate freezing method for the Hanwoo in vitro matured oocytes and that ovum bank can be maintained efficiently by MVC cryopreservation method.

• Journal of The Korean Association For Science Education
• /
• v.29 no.8
• /
• pp.990-1010
• /
• 2009

To derive brain-based evolutionary educational principles, this study examined the studies on the structural and functional characteristics of human brain, the biological evolution occurring between- and within-organism, and the evolutionary attributes embedded in science itself and individual scientist's scientific activities. On the basis of the core characteristics of human brain and the framework of universal Darwinism or universal selectionism consisted of generation-test-retention (g-t-r) processes, a Model of Brain-based Evolutionary Scientific Teaching for Learning (BEST-L) was developed. The model consists of three components, three steps, and assessment part. The three components are the affective (A), behavioral (B), and cognitive (C) components. Each component consists of three steps of Diversifying $\rightarrow$ Emulating (Executing, Estimating, Evaluating) $\rightarrow$ Furthering (ABC-DEF). The model is 'brain-based' in the aspect of consecutive incorporation of the affective component which is based on limbic system of human brain associated with emotions, the behavioral component which is associated with the occipital lobes performing visual processing, temporal lobes performing functions of language generation and understanding, and parietal lobes, which receive and process sensory information and execute motor activities of the body, and the cognitive component which is based on the prefrontal lobes involved in thinking, planning, judging, and problem solving. On the other hand, the model is 'evolutionary' in the aspect of proceeding according to the processes of the diversifying step to generate variants in each component, the emulating step to test and select useful or valuable things among the variants, and the furthering step to extend or apply the selected things. For three components of ABC, to reflect the importance of emotional factors as a starting point in scientific activity as well as the dominant role of limbic system relative to cortex of brain, the model emphasizes the DARWIN (Driving Affective Realm for Whole Intellectual Network) approach.