• Journal of Environmental Science International
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• v.16 no.5
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• pp.549-559
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• 2007

Vegetation surveys were performed at 45 plots along 10 highways cut slopes in South Korea. Total floral inventory, species richness and exotic plant percentage were obtained within each plot. Life history and life form of each species appeared were analyzed. Community types were classified using hierarchical cluster analysis and detrended correspondence analysis and non-metric multidimensional scaling were conducted from vegetation matrix. 292 species of vascular plants were discovered and the number of natives and exotics were 226 and 66, respectively. There were no significant differences of species richness and exotic plant percentage between cut slopes and rest areas. Hierarchical cluster analysis indicated five clear vegetation associations in cut slopes and rest areas. Detrended correspondence analysis indicated that species composition of total and native plants were similar along the highway cut slopes whereas exotic plants were distributed differentially along the highway cut slopes. in non-metric multidimensional scaling, the studied sites were more separated from each other on the basis of their species composition than the results of detrended correspondence analysis with respect to total, native and exotic plants. The both ordination represented that exotic plants have not been made uniform yet on cut slopes and rest areas by highway corridor in spite of diverse chronosequences after highway construction termination (1 to 22 years). This study showed that the distribution of species composition in exotic plants was different and localized on cut slopes and rest areas of highway in this representative peninsula area of North East Asia and the invasion of exotic plants can retard the process of plant species homogenization.

• Korean Journal of Veterinary Research
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• v.30 no.4
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• pp.473-478
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• 1990

This survey was conducted to observe the prevalence of blood parasites in slaughtered cattle included Korean native cattle, Charolias, Hereford, Aberdeenangus and Holstein breeds in the Western area of Kyeongnam. The results obtained are summarized as follows: 1. The prevalence of T sergenti was shown 71.8% as 395 heads of a total of 550 heads examined and from Jaunary to November the monthly prevalence of T sergenti was shown the range of 61.1% to 84% except 38.5% in December. The other blood parasites included Babesia and Anaplasma were not detected from the blood samples except Setaria spp microfilariae. 2. The distribution of parasitaemia levels of T sergenti in positive cattle was shown 93.9% in the range of 1~10/1000 rbc, 4.1% in 11~20, 1.3% in 21~30 and 0.8% above the range of 31. 3. The pervalence of T sergenti by breeds of slaughtered cattle was shown 71.2% in Korean native cattle, 72.7% in Charolias, 78.3% in Hereford and 81. 8% in others (Aberdeen-angus and Holstein) respectively. Also the parasitaemia levels in these cattle were shown higher levels in imported cattle included Charolias, Hereford, Aberdeen-angus and Holstein breeds comparing with Korean native cattle. 4. The prevalence of Setaria spp microfilariae in slaughtered cattle was shown 6.9% and by monthly prevalence of the parasite was shown higher in March, April and May compared with June, July, August and October. But in the winter season included January, February, November and December the parasite was not detected from the blood samples. 5. The distribution of parasitaemia levels of Setaria spp microfilariae per ml of blood was shown 65.8% in the range of 1~50, 13.2% in 51~100 and 10.5% in 101~200 and above the range of 201, respectively.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.237-245
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• 2000

The regional distribution and relative frequency of somatostatin-immunoreactive cells in the gastrointestinal tract were studied during the postnatal development(1 day old, 1 month old, 6-month-old and adult) of the Korean native goat by immunohistochemical methods. Somatostatin-immunoreactive cells were found in the entire gastrointestinal tract and were most predominant in the fundic gland region except for the pyloric gland region of the 1 day old. The number of these cells was observed to decrease along the gastrointestinal tract and to decrease according to the increase with age in all postnatal stages. In this study, immunoreactive cells revealed the differences of regional distribution and the relative frequency in the gastrointestinal tract during postnatal development. These results suggest that although the functional significance of fetal endocrine cells remains unknown, this was caused by changing of feeding habits and physiological conditions during different ages.

• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.66-71
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• 1992

The ecological distribution of endomycorrhizas in evergreen woody species native to the evergreen forest ecosystem of Tadohae-haesang National Park in southern Korea in February, 1989 was studied. The abundance and diversity of vesicular-arbuscular (VA) mycorrhizal fungi were also determined. The spore densities ranged from 14 to 326 per 100 g of soil. Most of the spores of mycorrhizal fungi collected from 25 soil samples belonged to the genera Glomus and Gigaspora. The frequency and number of spores in Camellia japonica varied with location. Spores belonging to the genus Gigaspora were not found in Camellia japonica in Yesongri evergreen forests adjacent to the sea. Glomus sp. was the major constituent of the spore assemblage at this site. The most abundant species in Camellia japonica in the Yesongri evergreen forests in Pogildo was Glomus borealis. In the soil of a mountain at Buwhangri, in the central location of the island at an elevation of 250 m, Gigaspora sp. was present and Glomus sp. was a major constituent of the spore assemblage. In the urban area of Haenam spore densities were much higher than in the Pogildo area. The most abundant species in Camellia japonica in the urban area of Haenam was Gigaspora sp..

• Korean Journal of Environmental Agriculture
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• v.21 no.4
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• pp.291-296
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• 2002

In this investigation we tried to investigate the effect of oxalic acid on the fate of native sulfate in Bt soil that contained a high kaolinitic clay by observing the distribution of two anions using soil column under the given competitive adsorption between displaced and displacing anions. To do this, the soil columns uniformly packed to a bulk density of 1.25 $g/cm^3$ with Cecil Bt soil were disected and analyzed the amounts of sulfate and oxalic acid both in solution and solid phases after flowing the designated pore volumes of oxalic acid The results showed that two sets of curves-nonlinear (> $10^3M$) and linear (> $10^3M$) curves where the solution of oxalic acid was not adiustet while the approaches to the plateau were slow when pH of oxalic acid was adjusted to 5. The cumulative amount of sulfate desorbed by successive addition of oxalic acid was nonlinearly approached to the plateau at the concentration of $10^3M$ or greater, indicating that the number of addition of oxalic acid increased with decreasing order of oxalic acid. However, the plateau did not obtain where the concentration of oxalic acid were less than $10^4M$, showing a linear increase. Therefore, we may conclude that the rate-limited desorption was involved as the concentration of oxalic acid decreased.

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.181-186
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• 2003

To obtain the basic data for monitoring and the conservation of native plant species at the sub-alpine zone Jongseogdae in Jirisan (Mt.).40 plots(5m${\times}$5m) set up by random sampling method and the distribution of native shrub and herb species at the subalpine zone was surveyed. Leading shrub species at the subalpine zone of Jongseogdae were Tripterygium regelii with IP value of 23.45% : followed by Lespedeza maximowiczii, Symplocos chinensis for. pilosa and Lespedeza tomentella. Dominant species at the subalpine zone were Lysimachia clethroides, Pteridium aquilinum var. latiusculum, Synurus deltoides, Veratrum maackii var. japonicum, Hemerocallis fulva and Astilbe chinensis var. davidii. Rhododendron tschonoskii recorded from the rare and endangered species list of the Korea Forest Service distributed among the rocks on the top of Jongseogdae. The long-term sustainable habitat monitoring might be required to conserve this subalpine zone.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.755-760
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• 2008

The aim of this study was to produce resistant starch preparations from acid-modified com starches prepared at various hydrolysis levels (0.5-4.0 hr). Effect of autoclaving cycles on resistant starch (RS) formation was investigated. Molecular weight distribution, pasting and functional properties of acid-modified com starches were determined. For RS formation native and acid-modified starch samples were gelatinized and autoclaved (1 or 2 cycles). While native and acid-modified starches did not contain any RS, the levels increased to 9.0-13.5% as a result of storage at $95^{\circ}C$ after first autoclaving cycle. Second autoclaving cycle together with storage at $95^{\circ}C$ brought final RS contents of the samples incubated at 4 and $95^{\circ}C$ after the first cycle to comparable level. As acid modification level increased, the amount of high molecular weight fractions decreased, resulting in significant decreases in viscosities (p<0.05). The samples produced in this study had low emulsion stability and capacity values.

• Korean Journal of Environment and Ecology
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• v.36 no.3
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• pp.327-337
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• 2022

Ecological restoration is considered a good means to prevent biodiversity loss in terms of the ecosystem's health and sustainability. However, there are difficulties in putting it into practice as there is no comprehensive and objective standard for the selection of plant species, such as environmental, ecological factors, and restoration goal setting. Therefore, this study developed an evaluation index necessary for selecting plant species for restoration using the Delphi method that synthesizes the opinions of the expert group. A survey with 38 questionnaires was conducted twice for experts in ecological restoration, etc., and the importance and priority of evaluation indicators were analyzed by dividing the restoration targets into inland and island regions. The result of the importance analysis showed that "native plants" had the highest average of 4.9 among the evaluation indices in both inland and island regions, followed by "seed security", "propagation", and "root growth rate". In the inland region, the index priority was analyzed in the order of "native plants", "appearance frequency", "root growth rate", "distribution range", and "seed security" in the island region, it was analyzed in the order of "native plants", "root growth rate", "appearance frequency", "distribution range", and "tolerance", showing slight differences between the two indicators. As a result of the importance and priority indicator analysis, we set the mean importance and priority of 4.1 and 2.9, respectively, in the inland region and 4.2 and 2.9, respectively, in the island region. As for the criteria of selecting plant species for ecological restoration, the "native plants" had the highest importance and priority. "Seed securing", 'viability", "topography", "proliferation", "tolerance", "soil conditions", "growth characteristics", "early succession", "distribution range", "appearance frequency", and "germination rate" were classified into subgroups of low importance and priority. The lowest indicators were "final stage of succession", "transition period", 'transition stage", "root", "reproduction", "soil", "appearance", "technology", "landscape", "climate", and "germination rate". We expected that the findings through objective verification in this study would be used as evaluation indicators for selecting native plant species for ecological restoration.

• Animal cells and systems
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• v.3 no.3
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• pp.269-273
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• 1999

The distribution and relative frequency of somatostatin-immunoreactive cells in the pancreas were studied during developmental stages (fetus, neonate, 1-month-old, 6-month-old and adult) of the Korean native goat by immunohistochemical methods. Somatostatin-immunoreactive cells were detected in the exocrine of all ages, in the endocrine portions (pancreatic islets) from the neonate, and in the pancreatic duct of the 1-month-old. The relative frequencies of these cells in the pancreatic islets increased with age. However, there were no age-related changes in the relative frequencies of somatostatin-immunoreactive cells in the exocrine and pancreatic duct. Generally, they were distributed in the interacinar spaces, the epithelium of the pancreatic duct, or dispersed in the peripheral zone of the pancreatic islets in all ages. However, clusters consisting of 3-4 cells were also found in the subepithelial connective tissues from the 1-month-old. In addition, the distributions in the endocrine portions of the adult were divided into two patterns: 1) they are dispersed in the marginal regions with moderate or low frequencies, or 2) in the inner zone with high frequencies.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.434-437
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• 2003

This study was carried out to obtain basic information for environment of native area and growth characteristics under various mulching materials in Dendropanox morbifera $\textrm{L}_{EV}$, Dendropax c morbifera was grown wild at Wando area, particularly, distribution frequency was high at 20 to 280 meters above the sea level, and configuration of the ground of native area descended slowly toward the southeast. The soil characteristics of native area was pH 5.3-5.5, 8.8-9.5% in organic matter content and 19.8-22.0% in soil moisture. Growth of Dendropanox morbifera $\textrm{L}_{EV}$, was accelerated by transparent polyethylene film and black polyethylene film mulched.