• Korean Journal of Veterinary Research
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• v.33 no.2
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• pp.295-300
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• 1993

Central nervous system of two dogs with natural canine distemper was investigated histopathologically and immunocytochemically with antisera to MBP, MAG and GFAP. Histopathologically, there were neuronal degeneration and diffuse gliosis in the cerebrum, vacuolar degeneration, hypertrophy of astrocytes and demyelination in cerebellar white matter adjacent to the 4th ventricle and optic tracts showing non-inflammatory demyelinating encephalomyelitis (Summers and Appel, 1987). Immunohistochemically, there was a concurrent disappearance of MBP and MAG in the well developed demyelinating lesion in the cerebellar white matter. At the margin of demyelination, Loss of both MBP and MAG varied on the stage of demyelinating process. GFAP-positive astrocytes were hypertrophied and contained canine distemper virus intranuclear inclusions. GFAP-positive fibers were increased at the early stage of demyelination, and then were not immunoreaeted at the well developed demyelination. Hypertrophic astrocytes with intranuclear inclusions were commonly identified in the interfascular layer without myelin vacuolation and demyelination. This is the first study of primary demyelination and astroglial reactions in natural CDE investigated using immunocytochemistry of two myelin proteins and GFAP. Concurrent loss of MBP and MAG suggest that the myelin sheath is the target in the demyelinating process in CDE.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.4
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• pp.401-411
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• 2015

Drought stress has detrimental effects on the seedling development, vegetative/ reproductive growth, photosynthesis, root proliferation, anthesis, anthesis-silking interval (ASI), pollination and grain yield in maize. Typically, two weeks before silking through pollination are an important time in maize life. Here we reviewed the effects of drought stress on growth, physiological/ molecular researches for drought tolerance, and breeding to genomics in maize. Drought stress during kernel development increases leaf dying and lodging, decreases grain filling period and grain yield. Physiological factors of drought stress/ effects are water content, water deficits, and water potential. Nowdays molecular marker assisted breeding method is becoming increasingly useful in the improvement of new germplasm with drought stress tolerance.

• Applied Microscopy
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• v.36 no.4
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• pp.299-305
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• 2006

Onuf's nucleus, which is located in the ventral horn, has been known to innervate the striated muscles of the urethral and anal sphincter muscles via the pudendal nerve Onuf's nuclei are resistant to pathologic condition such as poliovirus. The reason why the motor neurons in Onuf's nucleus are less degenerated is not certain until now. The present study aims at updating the microscopical characteristics including its location the Onuf's nucleus innervating the external urethral sphincter, and ultrastructures of the zinc-enriched (ZEN) terminals synaptically-contacting with Onuf's motor neurons in the rat spinal gray matter by using HRP tracing method and zinc selenium autometallography, respectively. Based on HRP tracing method, Onuf's nuclei were located adjacent lateral dendritic projections of the ventral horn. Their shape was almost round at lumbar level, but oval at sacral segment of spinal cord. In size, their somata were smaller than that of other motor nuclei. In AMG stained sections, Onuf's nuclei were innervated by highly concentrated ZEN terminals, and contained small and middle-sized ZEN, but totally void of large ZEN terminals. AMG silver grains were confined to presynaptic ZEN terminals against dendritic elements and somata of the Onuf's motor neurons. A majority of the ZEN terminals contained flattened synaptic vesicles and made symmetrical synaptic specializations.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.1
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• pp.1-8
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• 2002

Chufa (Cyperus esculentus L.) belongs to one of the sedge family and pows well in summer. The aboveground part of chufa is mostly consisted of leaves and the underground part is mostly composed of a clump of fibrous root with tuber. At the seeding year, it does not reproductive development but produces a lot of tuber. It produced many tillers from the tuber and grows in clumps as a bunch type. The plant height of mature chufa was 73 to 75cm and it grown fully in the middle of July. The number of tillers were increased rapidly until the end of July and still increased slowly after August but it showed very poor growth. The final fresh weight and dry matter yield of aboveground part of chufa were 40.3 tou/ha and 12.1 tou/ha. respectively. The regrowth of aboveground part was vigorous in the early stage of growth after 1st cutting but it was decreased rapidly after the second cutting. In control plot, the number of tubers per a clump were 722 at final stage and their fresh and drymatter yields per m: were 4.2kg and 1.9kg, respectively. In experimental plots, the amount of tubers was decreased steadily according to delay of cutting date, but late cutting date was not affect the tuber formation severely because the tuber produced already early in August. The nutritive value of chufa in vegetative growth stage was good but it was decreased according to growing up. The contents of crude protein(CP), neutral detergent fiber(NDF), dry matter digestibility (DMD) and total digestible nutrients(TDN) of aboveground part of chufa harvested finally were 6.1%, 51.5%, 39.8%, 33.2% and 39.4％, respectively. The contents of crude protein(CP), neutral detergent fiber(NDF), dry matter digestibility(DMD) and total digestible nutrients(TDN) of tubers of chufa were 6.1%, 81.5%, 39.8%, 33.2% and 39.4%, respectively and the content of oil was as high as 16.2%, especially.

• Journal of The Korean Association For Science Education
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• v.22 no.3
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• pp.490-498
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• 2002

This study investigated the effects of the 'Meeting With Scientists' program on children's stereotypical images of scientist. To do those, 36 children of a fifth grade class participated in the program for one month. The program consisted of two main activities:(l) participating in scientists' lectures and exchanging e-mail with them; and (2) visiting web sites about scientist and science, and exchanging e-mail with scientists at the sites. The results of the study can be summarized as follows: First, after participating in the program, children showed the significant decrease of several stereotypical items, such as facial growth of hair(bald hair beard), symbols of research, and age of the scientist. Second, the most popular source of the images was the visual media at the pretest but the source was changed to the visiting and participating scientist's lecture, and internet at the posttest. The latter items appeared a significant difference between the pretest and the posttest, The results indicate that the program is effective to decrease of children's stereotypical physical image of scientist.

• The Korean Journal of Mycology
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• v.24 no.3 s.78
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• pp.228-236
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• 1996

Flesh fungi were collected during field trips to mountain areas throughout the country from May to October of 1994. Through the observation and identification of specimens belonging to the Aphyllophorales, one genus, Tylospora, and six species, Athelia fibulata, Hypochnicium punctulatum, Tylospora fibrillosa, Stereum ochraceo-flavum, Steccherinum litschaueri, and Oligoporus undosus were confirmed new to Korea and are registered here with descriptions.

• Korean journal of applied entomology
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• v.13 no.1 s.18
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• pp.25-31
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• 1974

This survey was aimed to accumulate basic data of aphid population at the Horticultural Experiment Station at Suweon. The yellow pan traps were setted at five locations (Fig.1.), and ran from May 1 to October 31. 1970. About one hundred and twenty species of aphids were trapped, including 24 species of plant vims vectors. Of these, dominant species were as follows: (Asterisk shows virus vector) Aphid species No. of catches * Aphis spiraecola PATCH 2,635, * Aphis craccivora KOCH 2,377, * Myzus persicae SULXER 2,111, Capitophorus hippophaes javanicus H.R. LAMBERS 2,051, Anoecia fulviabdominalis SASAKI 1,480, * Aphis gossypii GLOVER 867, * Macrosiphum avenae FABRICIUS 859, Cervaphis quercus TAKAHASHI 692, * Lipaphis erysimi KALTENBACH 645, Pleotrichophorus chrysanthemi THEOBALD 489, The above 10 species consisted $76.5\%$ of total catches and the 24 vector species consisted $55.5\%$. The curve of the seasonal occurrence of flying aphids at Horticultural Experiment Station shows bimodal, typical for the temperate region. The total number of trapped aphids at the Station from May to September, 1970, were less than that of average yearly catches at the College of Agriculture from 1967 to 1970. Thi, low numbers at Horticultural Experiment Station may attribute to the frequent spraying of insecticides from Spring to Summer on growing crops there. But the aphids population increase suddenly in the middle of October. This might be resulted from cease of insecticide applications and migration of aphids from summer host to winter host plants.

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.232-241
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• 2003

Mountain Chungyeong, 879m in altitude, is located in the northeast of the middle area in Korea. Around Mt. Chungyeong, many Korean endemic and rare plants are populated, so it is considered a very important biogeographical area where the temperature zones of northern and southern plants are crossed. Because it is close to Seoul, a capital of Korea, it is a common mountain where many tourists visit frequently. Continuous tourist's visit may cause a bad influence on vegetation around the climbing paths. Therefor, weed community around the climbing paths on Mt. Chungyeong, where visitors exert a bad influence directly on its community by coming in and out, was surveyed phytosocialogically. Our surveys have been accomplished from August, 2001 to September, 2002. weed communities formed around the climbing paths on Mt. Chungyeong were divided into several patterns and analysed. They have been divided into 5 communities and 5 subcommunities. Community A: Plantago asiatica community, A-a: Erigeron annuus subcommunity, A-b: Carex. lanceolata subcommunity, B: Pseudostellaria palibiniana community, B-a: Carex siderosticta subcommunity, B-b: Galium trachyspermum subcommunity, C: Pueraria thunbergiana community, D: Lespedeza maximowiczii community, E: Rubus crataegifolius community, F: Oplismenus undulatifolius community, The flora surveyed in these communities was constituted of 47 families, 101 genera, 17 varieties, and 149 species. Wild plants such as Plantago asiatica, Erigeron annuus, Erigeron strigosus, Pueraria thunbergiana, Lespedeza maximowiezii, Rubus crataegifolius, Artemisia princeps var. orientalis, Artemisia japonica and Lysimachia clethroides were mostly light loving plants and higher resistant plants against the stamping pressure. Our result from the ranking all surveyed areas by the Bray-Curtis ordination method was very similar to the results from phytosocialogical table analysis.

• Korean journal of applied entomology
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• v.36 no.2
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• pp.145-149
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• 1997

Occurrence pattern of major insect pests on 7 recommended potato cultivars in Korea was investigated from sowing to harvesting time at Kangneung and Daegwallyung experiment fields in 1996. Green peach aphid (Mym persicae Sulzer), potato aphid (Macrosiphum euphorbiae Thomas) and beet armyworm (Spodoptera enigua Hubner) were the major insect pests on potato leaves, and wireworm (Selatosomus puncticollis Mot.) was the major pest on tubers. There was a slight difference of average number of aphids per 50 leaves among cultivars; ranged from 22.7 on cv. Dejima to 46.3 on cv. Superior. Numbers of leaves damaged by beet armyworm larvae on cv. Shepody and cv. Jopung were 11.0 and 14.3, and these cultivars are thought to be resistant against the larvae infestation. However, degree of damage on cv. Dejima and cv. Namsuh was higher 10 times than cv. Shepody and cv. Jopung. In wireworm, the percentage of damaged tubers on cv. Irish Cobbler was lowest of 8.1%, and followed by cv. Superior, cv. Dejima, cv. Jopung, and cv. Atlantic. Whereas, those on cv. Namsuh and cv. Shepody were significantly high of 50.0% and 46.8%.

• Korean journal of applied entomology
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• v.31 no.2
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• pp.89-100
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• 1992

The study was conducted to investigate the community structure of superfamily Pentatomoidea(Geocorisae: Hemiptera) in Mt. Kyeryongsan from August, 1989 to August, 1990. The collected pentatomoid insects were composed of 34 species, 22 genera, and 5 families. Percentages of pentatomoid insects found in each observed zone were 45.4 % (22 species) in the paddy bank, 37.5% (26 species) in the weedy field and 17.0% (20 species) in the shrubs. Dominant species and Simpson's dominance indices were Eurydema rugosa and Carbula putoni ($\lambda$=0.125) in the paddy bank, Carbula putoni and Eurydema rugosa ($\lambda$=0.183) in the weedy field, Gonopsis affinis and Coptosoma biguttulum ($\lambda$=0.099) in the shrubs. Seasonal dom¬inant species were Eurydema rugosa and Dolycoris baccarum ($\lambda$0.207) in Spring, Carbula putoni and Eurydema rugosa ($\lambda$=0.1l5) in Summer, and Carbula putoni and Nezara antennata ($\lambda$=0.141) in Autumn. Species diversity indices(H') in paddy bank, weedy field, and shrubs were 1.034, 1.039, and 1.105, respectively. Evenness indices(J') were 0.770, 0.734, and 0.849, respectively. Community structures were almost similar between the weedy field and the shrubs.