• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.658-675
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• 2016

The environmental characteristics of the habitats, the population structures, ecological niche, life traits and the population demography are used as an essential informations to the effective conservation plans about the target species. We first confirmed a total of 37 populations through 12 years of investigation on the extents, and investigated the environmental factors of habitats and the population structures of the 25 cohorts in 12 regions among them. And, we investigated the population dynamics targeting at 8 cohorts in the population of Daegwanryeong-myeon, Pyeongchang-gun, Gangwon-do. Along with this, we conducted 4 years of cultivation experiments and how pollinators affect the success of reproduction. The results shows that the Paeonia obovata Maxim. was found in a relatively wide range of habitats. For the population structures of the 25 cohorts, there were considerable differences among cohorts, including a case which showed relative stable structure and an extreme case in which only adults were found. The factor that affected the population dynamics during the investigation was thought as a forest gap created in the tree layer. In the cultivation experiment, seedlings grew well in a less soil organic matter. The seed setting rate and the number of seeds generated by visiting pollinators were higher trends. In conclusion, to understand the distribution of the Paeonia obovata Maxim., there needs to be investigated on the other factors that are involved in dispersal factors other than environmental factors, and thus we suggest the necessity of the research on the dispersal vectors. The current Paeonia obovata Maxim. population was thought as a process of expansion after the rapid reduction of the extents in the past. For the effective conservation of the Paeonia obovata Maxim., an endangered plant, we recommend to understand the species through the spatio-temporal expansion, and maintain the health of the ecosystem based on it.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.201-205
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• 2002

This study was carried out to investigate storability and develop suitable storage method for barley. Rough and milled barley such as Olbori(covered barley), Ssalbori(naked barley) and Chalssalbori (waxy naked barley) were packaged in 3P bag and OPP film bag, respectively, and stored at ambient and low temperature warehouse conditions. The weight loss was higher in milled barley than that of rough barley during barley storage. Acid value, one of the most important factor for grain quality evaluation, was increased from 4.9-9.0 mg KOH/100g to 6.5-19.9mg KOH/100g in milled barley at 16 months after storage. Reducing sugar content was increased while germination and water absorption rates were decreased during barley storage period. In terms of penal taste of boiled barley, rough barley could be stored safely more than one year regardless of storage methods where-ase milled barley stored in ambient temperature ware-house produced nasty flavor at 8 to 10 months after storage.

• Korean Journal of Ichthyology
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• v.19 no.2
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• pp.154-159
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• 2007

The oblong rockfish, Sebastes oblongus has recently drawn attention from aquaculturists because of its marketable value and tolerance against winter water temperature in the southern coastal waters of the Korean peninsula. In the study of temperature effect on growth, water temperature $16^{\circ}C$ showed best growth. The upper temperature of the fish showed feeding activity was $27^{\circ}C$ over which the fish showed no longer feeding activity. Stocking density was also a critical factor affecting the growth and survival of the juvenile fish. The best growth was in the density of 200 juveniles/L, while the highest survival was in the density of 100 juveniles/L. A feeding experiment was conducted to determine the effects of feeding frequency on growth and survival. A feeding scheme of twice a day was good enough in the sense of growth, survival, and economy. These results indicate that parameters such as water temperature, density, tank size and feeding frequency are consideration for best seed production of the fish.

• Journal of Aquaculture
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• v.3 no.1
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• pp.89-125
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• 1990

In order to improve top shell seed production techniques spawning and larvae rearing were done in rearing tanks. Growth of young top shell in the nursing ground were also investigated. For induced spawning, top shells were maintained in still water during night time. Then they were treated with ultra violet iradiated sea water after dried up in air for 60 minutes. Spawning rate were 10 to $39.77\%$. It was found that young top shells moved in the growing grounds from nursing grounds when they reached approximately 30-40mm in shell heignt. Among main food algae for top shell in the natural growing grounds, sea mustard were melted away during June. Therefore, presence of another food algae such as Ecklonia cava or Sargassum spp. seems to be the main limiting factor for survival of top shell during summer. The tolerance of top shells ranging from 30mm to 60mm to low density of seawater for were tested at the temperature between 29.5 and $31.4^{\circ}C$. Hundred percent mortality occoured in 20, 55 and 90 hours after first stocking at the specific gravity of 1.010, 1.015, and 1.020, respectively.

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.107-114
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• 2007

Establishments of the seedlings inside the natural forest from adjacent artificial forests would be an important factor in forest stand dynamics. This study was conducted to see the invasion of Korean pine (Pinus koraiensis) seedlings which is not native in this region, into the natural deciduous broad-leaved forest in Gwangneung, Korea. There is no mother tree at the I ha study site while the number of naturally regenerated P. koraiensis seedlings was 345 trees and 56% of them were clumped with more than two seedlings at each point. Applying the image segmentation method to IKONOS satellite image of January, 2003, the distance from the center of 1 ha study site to the nearest mother tree and plantation of Korean pine were 200 m and 270 m, respectively. The average height and root-collar diameter of the seedlings were 34 em and 7 mm, respectively and the age of 207 seedlings (60%) were below 5 years old. Most abundant range of soil moisture gradient and LAl (leaf area index) were from 16 to 20% and those of LAI were from 3.1 to 3.5. To understand the dynamics and seed dispersal pattern of Korean pine in the Gwangneung natural deciduous broad-leaved forests, additional studies not only long-term monitoring of growth and mortality of naturally regenerated Korean pine seedlings but also application of stable isotope analysis and molecular genetic techniques was recommended.

• Reproductive and Developmental Biology
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• v.35 no.4
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• pp.441-447
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• 2011

The study aim is to investigate the free radicals scavenging and spermatogenic potentials, as well as to analyze any reproductive toxicity of ethanolic extract of Mucuna prureins (M. pruriens) Linn. in spermatozoa, under different dosages in normal male rat. Normal rats were randomly selected and suspension of the extract was administered orally at the dosages of 150, 200 and 250 mg/kg body weight of the different groups of male rats (n=6) once in a day for 60 days and grouped as group II, III and IV respectively. Saline treated rats served as control -group I. On the $60^{th}$ day the animals were sacrificed and the epididymal sperm were subjected to various analyses like level of ROS production, LPO, enzymatic and non enzymatic antioxidant, morphology, morphometry, chromosomal integrity and DNA damage. Results showed significant reduction in ROS production and peroxidation and significant increase in both enzymic and non-enzymic antioxidants in all concentration treated groups when compared with control. Results from all the drug treated groups showed good sperm morphology, increased sperm count and motility. There was no DNA damage and showed normal chromosomal integrity even in 250 mg/kg dose. When compared with control all the three extract treated groups showed increased ROS scavenging activity. However, group II (200 mg/kg) showed significant changes in all the parameters. From the present study it was confirmed that the M. pruriens has potential to improve the sperm qualitatively and quantitatively through scavenging the excess ROS with any adverse side effects. These observations suggest that ethanolic seed extract of M. pruriens may serve as anti-oxidant that can exploit to treat the oxidative stress mediated male factor infertility.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.8-15
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• 1994

The mode of safening action and potency of the 1, 8-naphthalic anhydride(NA) were investigated in corn(Zea mays) and soybean(Glycine max) treated with herbicide bensulfuron[2-{{{{{(4,6-dimethoxy-2-pyrimidinyl)amino}carbonyl}amino}sulfonyl}methyl}benzoic acid] and imazaquin[2-{4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl} 3-quinolinonecarboxylic acid]. Seed dressing with 0.2%(w/w) NA showed successful protection in corn against injury from herbicide bensulfuron and imazaquin but not in soybean. Safening factors of NA against bensulfuron and imazaquin were 10.2 and 5.0, respectively, in corn, while they were both 1.3 in soybean. In vivo, Glutathione-S-transferase(GST) activity of NA-treated corn and soybean increased 1.8-and 1.3-fold, respectively, but the activity was not affected by the herbicides in vitro. Acetolactate synthase(ALS) levels of NA-treated corn was increased 1.3-fold, but not changed in soybean. Tolerance of ALS activity to the herbicides was slightly greater in ALS obtained from NA-treated corn than that from the untreated, whereas the difference was not found in soybean. A significant increase of ACCase due to NA occurred in corn, but not in soybean. The herbicides did not affect in vitro ACCase activity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.3
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• pp.303-309
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• 1989

Present study was conducted to reveal the effects of the herbicides, Lasso and Devrinol, on the soybean growth and the nodulation in field condition. Emergence rate was reduced positively in proportion to increase in the concentration of herbicides regardless of the herbicidal difference and it was significantly reduced even in the recommended concentration as compared to untreated plot, showing marked abnormal symptom on seedlings. Plant height, fresh weight of the plant, number of internodes, branches, pods, seeds per plant and 100-seed weight were reduced with increase in the concentration of herbicides and were highly significant in difference between the untreated plot and double concentration plot, eventhough most were nonsignificant in difference from the recommended concentration. Nodulation was significantly decreased with increase in the concentration of herbicides. The reduction was remarkably different with soybean varieties and consistently appeared from three weeks to six weeks after sawing. Significant correlation was realized between the reduction of nodulation and the agronomic characters of soybean and it was considered that the reduction of nodulation by misapplication of the herbicides might be a causal factor for decrease in soybean yield.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2009.02a
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• pp.49-57
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• 2009

The cloning of canids was succeeded in 2005, several years after the birth of Dolly the sheep and also after the cloning of numerous other laboratory and farm animal species. The delay of successful somatic cell nuclear transfer (SCNT)was due to the unique reproductive characteristics of the female dogin comparison to other domestic mammals, such as ovulation of immature canine oocyte and a requirement of 25 days for the completion of meiosis within the oviduct (Holst & Phemister, 1971). When the technology for the recovery of in vivo matured oocyte was established, the application of cloning also became possible and cloned dog offspring were obtained. This report summarizes the progress of technical procedures that are required for cloning canids and the application of this technique. The first cloned dog, Snuppy, was achieved using an in vivo-matured oocyte which was enucleated and transferred with an adult skin cell of male Afghan hound. After establishment of a criterion of well-matured oocyte for the improvement of SCNT efficiency, we obtained three cloned female Afghan hound and a toy poodle cloned from 14 year-old aged Poodle using SCNT through this factor. To date, cloned dogs appeared to be normal and those that have reached puberty have been confirmed to be fertile. Through application of canine SCNT technique, first, we demonstrated that SNCT is useful for conserving the breed of endangered animal from extinction through cloning of endangered gray wolves using inter-species SCNT and keeping the pure pedigree through the cloning of Sapsaree, a Korean natural monument. Secondly, we showed possibility of human disease model cloned dog and transgenic cloned dog production through cloning of red fluorescent protein expressing dog. Finally, SCNT can be used for the propagation of valuable genotypes for making elite seed stock and pet dog. In summary, dog cloning is a reproducible technique that offers the opportunity to preserve valuable genetics and a potential step towards the production of gene targeted transgenic cloned dogs for the study of human diseases.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.2
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• pp.57-64
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• 1980

Seed tunicates of Halocynthia roretzi (v. DRASCHE) which were artificially settled in Chungmu area were transplanted to Seonyudo and Eochungdo to know the feasibility of the tunicate culturing in the western coast of Korea. From April 1978 to March 1979, the growth of the transplanted tunicate in the two area was compared and analyzed in reference to the ecological factors. At the time when the seeds were transplanted, the mean body height of Halocynthia roretzi(V. DRASCHE) was 1.84 mm, body breadth 1.42 mm, and the body weight 15.0 mg. After 333 days the mean body height was 10.77 mm, body breadth 6.75 mm, and body weight 201 mg in Seonyudo area. In Eochungdo area the mean body height was 13.5 mm, body breadth 11.51 mu and body weight 880 mg. According to above results, it is possible to culture the seeds in Eochungdo area. Salinity $(29.2-32.0\%_{\circ})$ was favorable, water temperature $(6.8-26.8^{\circ}C)$ was not a critical factor, but the growth of the tunicate was affected by the high temperature$(over\;25.0^{\circ}C)$ in July. Transparency lower than 1.0 m seriously affects the growth of the tunicate, and it was one of the important factors inhibiting the growth of the tunicate. Seonyudo area was found out to be inadequate for the culture of the sea spuirt Halocynthie roretzi because of the retarded growth in body breadth and weight while showing extended growth in body length then leading to higher mortality owing to large amount of silting and fouling of the colonial tunicate, Didemnum (didemnum) moseleyi.