• Reproductive and Developmental Biology
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• v.29 no.3
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• pp.175-180
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• 2005

This study was conducted to examine the effects of demecolcine-assisted enucleation and recipient cell cycle stage on the development of bovine somatic cell nuclear transfer (NT) embryos. In vitro cultured oocytes for $16\~20$ h were classified by first polar body (1st PB) extrusion and cell cycle stage (MI and MII) and treated $0.4\;{\mu}L/mL$ demecolcine for 40 min before enucleation. Enucleated oocytes were fused electrically with bovine ear skin cells, activated by Ca-ionophore+DMAP, and cultured in vitro. Most of eggs ($86.2\%$) treated with demecolcine protruded a chromosome mass and enucleated efficiently ($98.8\%$, (P<0.05). Demecolcine did not have a deteriorative effect on the development of NT embryos. Developmental rate of NT embryos reconstituted with oocytes extruded 1st PB significantly higher than that of NT embryos produced by oocytes without 1st PB ($18.2\%\;vs.\;4.6\%\cdot$, P<0.05). Cleavage and blastocyst formation rate of embryos reconstituted with MI oocytes ($69.4\%\;and\;5.9\%$, respectively) were significantly lower than those of embryos reconstituted with MII oocytes ($96.7\%\;and\;23.9\%$, respectively, P<0.05). From the present result, it is suggested that domecolcine is useful for the enucleation of recipient oocytes in bovine NT procedures, and MII oocytes rather than MI oocytes are more appropriate for recipient cytoplasm. Although, the potential to develop into blastocysts of NT embryos produced by 1st PB-nonextruded and MI oocytes was very low, these oorytes could be used for NT.

• Food Science and Preservation
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• v.23 no.2
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• pp.145-154
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• 2016

This study investigated the possibility of usage of freeze-dried ingredients for the preparation of Nabak kimchi. The quality characteristics of Nabak kimchi using freeze-dried ingredients (radish, kimchi cabbage, green onion, garlic and ginger) were monitored during storage at $4^{\circ}C$. The initial pH of Nabak kimchi was 5.76~5.93, however, it decreased significantly over increasing storage periods (p<0.05). The titratable acidity of Nabak kimchi increased during storage, reaching 0.43~1.08%. Among the freeze-dried samples, those treated with freeze-dried radish and minor ingredients showed lower titratable acidity than that of the control. The initial number of total aerobic and lactic acid bacteria were 5.57~6.25, and 5.52~6.24 log CFU/g, respectively. After 28 days, the population of total aerobic and lactic acid bacteria in the raw ingredients and freeze-dried minor ingredients was less than 8.0 log CFU/g, but more than 9.0 log CFU/g in other samples. Yeasts and molds in Nabak kimchi were detected up to 2~3 log CFU/g, but coliforms were not detected in all samples during storage. The score of firmness and overall acceptability in the control, raw ingredients and freeze-dried minor ingredients were significantly higher than others (p<0.05). These results indicated that freeze-dried ingredients, such as green onion, garlic, and ginger, can be used in kimchi and would delay microbial growth and extend the shelf-life of kimchi without any deduction of sensory quality.

• Korean Journal of Plant Resources
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• v.12 no.3
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• pp.240-252
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• 1999

Floristic composition and phytosociological studies of Mt. Chongok and Mt. Tuta were investigated, and that was compared with the previously published report in 1993. Vascular plants were composed of 100 families, 358 genera, 573 species, 95 varieties, and 18 formae, totaling 686 taxa. The vegetation was relatively well conserved based on Pteridophyta calculation (Pte-Q), 1.13. Compared with the vascular plants of the southern and northern slope area, the vascular plants of the southern slope area were composed of 87 families, 287 genera, 419 species, 73 varieties, and 11 formae, totaling 503 taxa, and those of the northern slope area consisted of 94 families, 293 genera, 427 species, 73 varieties, and 12 formae, totaling 512 taxa, respectively. Also, compared with the taxa in each side, both sides were composed of 332 species in common, southern sides, 172 species and northern sides, 182 species, respectively. The number of species of 11 families belonged to the higher level among total families taxa was composed of 328 species(47.8%). Among them, Compositae and Rosaceae were included much more species than remnant families. Korean endemic species were composed 16 families, 24 genera, 20 species, 8 varieties and 2 formae, totaling 30 species(4.4%). Compared with the Korean endemic taxa in each side, both sides were composed of 14 species in common, southern sides, 11 species and northern sides, 5 species, respectively. A naturalized plants were 20 species, correspond to 9.2% of totaling 218 species appeared in South Korea. Among them,12 species were appeared commonly in both sides, southern sides, 16 species and northern sides, 16 species, respectively. Life form spectra was H-D1-R5-e type and, useful resources plants are as follows; edible source(42.4%), medicinal source(31.5%), ornamental source(15.6%) and pasture source (13.3%) in the total region. The forest vegetation of the southern slope was classified into 1 order, 1 alliances and 5 communities; Rhododendro-Quercetalia mongolicae, Lindero-Quercion mongolicae, Quercus mongolica Typical community, Populus davidiana-Quercus mongolica community, Pinus koraiensis-Taxus cuspidata community, Pinus densiflora-Carex humilis var. nana community, Betula costata-Betula ermanii community. It is considered that the slight difference of the flora and vegetation in the northern and southern slope is mostly due to the topographical and climatic difference. Even closer investigation is required for the more accurate comparison in this area.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.321-325
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• 2002

For examination, amaranth was first dried its surface after sufficient soaking in water. Dried amaranth was roasted when the moisture contents reached 30∼50%, its nasty smell disappeared and its color turned to yellow and it was puffed. Pretreated amaranth was added to biscuit for the improvement of apparence and merchandise value. The maximum expansion was reported at the moisture percentage of 130∼160% according to the examination of expansion and moisture percentage. In order to compare gelatinization of different processing, three different amaranth were prepared as follows ; Raw amaranth, steamed/dried amaranth, and roasted amaranth. The degree of gelatinization was increased as the percentage of moisture was increased and the degree of gelatinization of roasted amaranth was higher than the one of steamed/dried amaranth, their moisture contents were 62.10% and 57.59%, respectively In addition, the hardness($\times$10$\^$5/dyn/㎠) of roasted amaranth was showed lower values than that of steamed amaranth and raw amaranth were showed the large values. After examining biscuits containing each amaranth, raw amaranth had problem with nasty smell and bad texture, and streamed/dried amaranth were able to remove viscosity but turned brown. Biscuits containing roasted amaranth had good smell and texture, and besides the color of biscuits became bright because roasted amaranth turned white. Biscuits tasted best when it contained 5% of roasted amaranth. The rancidity of biscuits with 5% roasted amaranth were proceeded slowly while roasted amaranth itself had high acid value and peroxide value. For the safety from oxidation, it was fairly safe for about 6 months.

• Reproductive and Developmental Biology
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• v.28 no.3
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• pp.161-166
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• 2004

This study was designed to evaluate the effects of nitric oxide scavenger (hemoglobin) and inhibitor (L-nitro-L-arginine methyl ester; L-NAME) with or without cumulus cell on the development of bovine IVM/IVF embryos. When CR/sub 1aa/ medium were supplemented with different dosage (lug/m, 5ug/m and 10ug/ml) of hemoglobin at 48hrs for in vitro culture, the proportion of embryos developing beyond morulae stage in 0, 1ug/ml and 5ug/ml with or without cumulus cell were 23.8%, 33.3 % and 26.8%, and 39.5%, 54.8% and 48.8%, respectively. There was a significantly difference the developmental rate of 1ug/ml hemoglobin intact cumulus cells to any other groups (P<0.05). On the other hand, when added to hemoglobin at 96 hrs, 1 ug/ml hemoglobin with cumulus cell group was significantly increased the percentage of developing into morulae and blastocysts to any other groups (P<0.05), and similar trend that of added at 48hrs. The overall means of the percentage of developing into morulae and blstocysts in 1ug/ml hemoglobin group was significantly increased than those of any other groups (P<0.05) and cumulus co-culture with hemoglobin was increased the in vitro developing rate of IVM/IVF embryos. In CR/sub 1aa/ medium treated with L-NAME 0, 10, 50 and 100mM, the developmental rate of morula plus blastocysts were 55.6%, 64.9%, 58.8% and 66.7%, respectively. The L-NAME did not affect the developmental rate and the cell numbers of blastocysts in all treated groups. These results indicate that hemoglobin and cumulus co-culture can increase the proportion of embryos that developed into morulae and blastocysts, but cell numbers of blastocysts were not affect in all groups.

• Journal of Food Hygiene and Safety
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• v.37 no.2
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• pp.87-96
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• 2022

Recently, the purchase of fresh-cut produce and meal kits has increased. Ready-to-eat (RTE) fresh-cut products have potentially hazard of cross-contamination of various microorganisms in the processes of peeling, slicing, dicing, and shredding. There are frequent cases of protozoa food poisoning, such as Cyclospora and Cryptosporidium, caused by fresh-cut products. The objective of the study is to investigate the microbiological qualities of various types of RTE fresh-cut products in the domestic on/offline markets. RTE fresh-cut fruits cup (n=100), fresh-cut vegetables (n=50), and vegetables in meal kits (Vietnamese spring rolls and white radish rolls kits, n=50) were seasonally analyzed. The contamination levels of hygienic indicator organisms, yeast and mold (YM), and foodborne pathogens (Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Salmonella spp., and Escherichia coli O157:H7) were monitored. Overall, the lowest microbiological qualities of meal kits vegetables were observed, followed by RTE fresh-cut fruits cup and fresh-cut vegetables. Contamination levels of total aerobic bacteria, coliforms, and YM in meal kits vegetables were 5.91, 3.90, and 4.71 logs CFU/g, respectively. From the qualitative analysis, 6 out of 200 RTE fresh-cut products (3%) returned positive result for S. aureus. From the quantitative analysis, the contamination levels of S. aureus in purple cabbage from a meal-kit and fresh-cut pineapple were below the acceptable limit (100 CFU/g). Staphylococcus enterotoxin seg and sei genes were detected in RTE fresh-cut celery and red cabbage from meal-kits, respectively. S. aureus contamination must be carefully controlled during the manufacturing processes of RTE fresh-cut products. Neither Cyclospora cayetanensis nor Cryptosporidium parvum was detected in the samples of RTE fresh-cut products and vegetables from meal-kits from the Korean retail markets.

• Journal of the Korean Geographical Society
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• v.30 no.3
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• pp.242-254
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• 1995

The Hadano Basin is located at a distance of about 70kms and 60kms from Tokyo and Yokohama and lies in the south-west part of the Kanto region in Japan. The basin area, which correspoends to the catchment of the Kaname River, is about areal size of 60.7$\textrm{km}^2$ and extends about length of 8kms in E-W direction and about width of 5kms in N-S direction (Fig.1). The Hadano basin is filled with thick pile of the alluvum from deposits composed of volcanic materials, mostly came from the Hakone Volcano and overlain by Fuji Volcanic ashes. Fluvial deposits form the good aquifer, therefore water resources of Handano City has been largely depending upon the eroundwater. Urbanization and industrialization of the basin has been rapid in the last thirty years, after activation of "Factory Attraction Policy of Hadano City" in 1956. Growth in population and number of factory due to urbanization changed the land-use pattern of the basin rapidly and increased the water demands. Therefore, Hadano City exploited a new source of water supply, and have introduced the prefectureal waterworks since 1976. On the other hand, the rapid urbanization has brought about the pollution of streams in the basin by domestic sewage and industrial waste water. Diffusion rate of sewerage systems in Hadano City is 38% in 1993. In ordcr to examine the impact of anthropogenic factors on river environments, the author took up the change of land-use and diffusion area of sewerage as parameters, and performed field surveys on water discharge and quality. The survey has been made at upstream and downstream of the main stream regularly per month, to get informati ons about the variation of discharge and water quality aiong the stream and its diurnal fluctuation. Annual variation has been analyzed based the data from Hadano City Office. The results are summarized as follows. 1. Stream discharge has been increasing by urbanization (Fig.3). Water quality (C $l^{-10}$ , N $H^{+}$$_{ 4}$-N, BOD) has been improving gradually after the application of sewerage service, yet water pollution load at the lower station has increased than that at the upper one because of the larger anthropogenic discharge volumes (Fig.4). 2. Corrclation coefficient of discharges between upper and lower was 0.81-0.92. Pollutant loads of the R. Kamame after the confluence with R. Kuzuha grew up by 2.4-3.7 times as compared with its upper reaches, and it increased to 3.7-6.9 times after the confluence with the R. Muro (Fig.5). 3. The changes of water quality along the stream can be divided into two groups (Fig.6a). First: water quality of the R. Kaname and R. Shijuhachisse is becoming worse towards the lower reaches because the water from branches are polluted. Second: water quality are improved in the lower where spring and small branch streams supply clear water, for example R. Mizunashi, R. Muro and R. Kuzuha. 4. Measured discharge at the upper station in the R. Shijuhachisse is 0.153㎥/sec, and about 55% of this is recharged until it reaches to the lower point. The R. Mizunashi has a discharge of 1.155㎥/sec at the upper point, is recharged 0.24㎥/sec until the midstream and groundwater spring 0.2㎥/sec at the lower reaches. R. Kuzuha recharged all the mountain runoff (0.2㎥/sec) at the upper reaches. The R. Muro is supplied by many springs and the estimated discharge of spring was 0.47㎥/sec (Fig.6b). 5. Diurmal variations in discharge and water quality are influenced clearly by domestic and industrial waste waters (Fig.7, 8).ed clearly by domestic and industrial waste waters (Fig.7, 8).

• Korean Journal of Weed Science
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• v.10 no.4
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• pp.269-276
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• 1990

Weed species belonging to the broadleaf family prevailed in the experimental sites followed by Cyperucea and grass family. In terms of life cycle, the dominant weed species were the perennial weeds rather than annual weeds. Most of weeds were emerged between 30-60days after transplanting in Chuncheon and between 40-60 days after transplanting in Hongcheon and Hoengseong areas. Among agronomic characteristics of rice affected by weed emergence were decrease of plant height by 2-4㎝, panicle number by 1.3-2.9, spkelet by 3. 7-7.5, ripening rates by 3.3-6.5%, and milled yield by 12-17%.

• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.11-15
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• 1982

The growth rate and heat resistance of two types of Bacillus cereus isolated from cooked rice were observed. The FB-1 strain showed positive to haemolysis and negative to starch hydrolysis, but FB-2 strain positive to both reaction. The cell number of B. cereus FB-1 reached to more than $10^7\;cells/ml$ within 6 to 12 hours at $25{\sim}35^{\circ}C$ when cultured on the medium of cooked rice homogenate (cooked rice 30g-phosphate buffer solution 80 ml), but the numbers at its maximum growth were only $10^4{\sim}10^6\;cells/ml$ at $45{\sim}55^{\circ}C$. The specific growth rate of FB-1 strain were $0.82hr^{-1}\;at\;20^{\circ}C$, $1.76hr^{-1}\;at\;30^{\circ}C$, $2.21hr^{-1}\;at\;35^{\circ}C$ and $1.84hr^{-1}\;at\;40^{\circ}C$, respectively. D-values of FB-1 and FB-2 spores at $70{\sim}100^{\circ}C$ were in the range from 18 to 3.1 min and 23.5 to 3.7 min, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.371-384
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• 1982

Highly cold tolerant varieties are requested not only at high latitute cool area but also tropical high elevated areas, and the required tolerance is different from location to location. IRRI identified 6 different types of cold tolerance required in the world for breeding purpose; a) Hokkaido type, b) Suweon type, c) Taipei 1st season type, d) Taipei 2nd season type, e) Tropical alpine type and, f) Bangladesh type. The cold tolerance requested in Korea is more eargent in Tongil group cultivars and their required tolerance is the one such as the physiological activities at low temperature are as active as in Japonica group cultivars at least during young seedling stage and reproduction stage. With conventional Japonica cultivars, such cold tolerant characters are requested as short growth duration but stable basic vegetative growth, less sensitive to high temperature and less prolonged growth duration at low temperature. The methods screening for cold tolerance were developed rapidly after the Tongil cultivar was reliesed. The facilities of screening for cold tolerance, such as, low temperature incubator, cold water tank, growth cabinet, phytotron, cold water nursery in Chuncheon, breeding nursery located in Jinbu, Unbong and Youngduk, are well established. Foreign facilities such as, cold water tank with the rapid generation advancement facilities, cold nurseries located in Banaue, Kathmandu and Kashimir may be available for the screening of some limitted breeding materials. For the reference, screening methods applied at different growth stages in Japan are introduced. The component characters of cold tolerance are not well identified, but the varietal differences in a) germinability, b) young seedling growth, c) rooting, d) tillering, e) discolation, f) nutrition uptake, g) photosynthesis rate, h) delay in heading, i) pollen sterility, and j) grain fertility at low temperature are reported to be distinguishable. Relationships among those traits are not consistent. Reported studies on the inheritance of cold tolerance are summarized. Four or more genes are controlling low temperature germinability, one or several genes are controlling seedling tolerance, and four or more genes are responsible for the pollen fertility of the rice treated with cold air or grown in the cold water nursery. But most of those data indicate that the results may come out in different way if those were tested at different temperature. Many cold tolerant parents among Japonicas, Indicas and Javanicas were identified as the results of the improvement of cold tolerance screening techniques and IRTP efforts and they are ready to be utilized. Considering a) diversification of germ plasm, b) integration of resistances to diseases and insects, c) identification of adaptability of recommending cultivars and, d) systematic control of recommending cultivars, breeding strategies for short term and long term are suggested. For short term, efforts will be concentrated mainly to the conventional cultivar group. Domestic cultivars will be used as foundation stock and ecologically different foreign introductions such as from Hokkaido, China or from Taiwan, will be used as cross parents for the adjustment of growth durations and synthsize the prototype of tolerances. While at the other side, extreme early waxy Japonicas will be crossed with the Indica parents which are identified for their resistances to the diseases and insects. Through the back corsses to waxy Japonicas, those Indica resistances will be transfered to the Japonicas and these will be utilized to the crosses for the improvement of resistances of prototype. For the long term, efforts will be payed to synthsize all the available tolerances identified any from Japonicas, Indicas and Javanicas to diversify the germ plasm. The tolerant cultivars newly synthsized, should be stable and affected minimum. to the low temperature at all the growing stages. The resistances to the diseases and insects should be integrated also. The rapid generation advancement, pollen culture and international cooperations were emphasized to maximize the breeding efficiency.