• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.4
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• pp.55-60
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• 2010

Rodents can recognize objects by using their whiskers. Not only rodents but also mammals use their whiskers to recognize objects. However, rodents can discriminate surface roughness in micrometer resolution throughout their whisker sensing. Rats can distinguish an target object's shape, roughness and surface pattern by moving their whisker back and forth freely. Mechanoreceptors surrounding the whisker in their follicle measure deflection and vibration of the whisker. In this paper, we designed biomimetic whiskers modeling rodent whiskers and showed the characteristic properties to extract the information of surface roughness.

• The Korean Journal of Zoology
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• v.19 no.1
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• pp.7-14
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• 1976

The release of ovulatory level of LH from the pituitary gland occurred between 51 and 56 hours after PMS treatment in 24-day old female rats. Estradiol given simultaneously with PMS advanced LH release 24 hours. Injections of estradiol $(2.5\\sim 40\\mu g)$ at 0, 24 and 48 hours failed to increase pituitary LH level by 51 hours after the first injection in ovariectomized rats. However, $5 \\mu g$ estradiol at 0, 24 and 48 hours followed by 1 mg progesterone at 48 hours elevated pituitary L level by 51 hours in ovariectomized rats. These results indicate that advancement of PMS-induced ovulation by estradiol in the previous study occurred by means of inducing premature release of LH and estrogen might synergize with progesterone in the regulation of LH in the pituitary gland.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.205-207
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• 2010

Stem and petiole rot symptoms of Valeriana fauriei occurred sporadically in the herb exhibition field in Gyeongsangnam-do Agricultural Research and Extension Services, Hamyang-gun, Gyeongnam Province in Korea. The typical symptom is water-soaking on the stem, rotting, wilting, blighting and the infected plants eventually died. White mycelial mats spreaded over lesions, and then sclerotia were formed on the infected plant parts and near soil surface line. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii. This is the first report of stem rot on Valeriana fauriei caused by Sclerotium rolfsii in Korea.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.333-339
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• 2023

The aim of this study was to collect information regarding the sex ratio, size at sexual maturity, and the primary spawning period of Hexagrammos otakii. The sex ratio (female : male) was observed to be 1 : 1.2 (n =739 : 906, with females comprising 81.6% of the population). The gonadosomatic index (GSI) exhibited its highest values in November for females and October for males, coinciding with the primary spawning period from November to January. The total length required for 50% sexual maturity was determined through a logistic regression model and found to be 23.1 cm for females.

• Korean journal of applied entomology
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• v.13 no.3 s.20
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• pp.135-139
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• 1974

A survey on rodent damage to ripening rice was conducted in Sep.-Oct. in 1973 in order to indentify the habitat type which has the greatest influence on rodent populations and damage problems. Total 109 paddies were examined in three geographical regions in central part of Korea including Kangwon and Kyoungki Provinces, which represents mountainous, coastal and rice plain lands. Sample paddies were selected according to the neighboring or surrounding habitats as farm villages, upland-crop fields, grassy river banks, forests and rice plains. Snap trapping was also conducted in each of habitats. In April, 1974, field trips were taken to representative parts of Korea visiting farmers and rural guidance officers involving more than 100 people for the information of existing local problems. The general damage of rice was considerably low in 1973 averaging $63\%$ in early ripening varieties and $0.26\%$ in standard varieties, white the average lost in 1971 was $14.2\%$ in early ripening varieties and $2.7\%$ in standard varieties. But the most of severe damages was occurred within 50 meters (practically none beyond 100m) of farm villages, caused mainly by Norway rat (Rattus rottfus Caraco) and striped field mouse (Apodemus agrarius). The examples of existing local problems confirmed that the rodent damage to field crops is closely associated with rodent populations that have survived the winter in and around farm houses and buildings.

• Journal of Nutrition and Health
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• v.17 no.4
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• pp.313-319
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• 1984

The effect of morphine on food intake on freely fed Sprague - Dawley rats was examined Opiate receptor binding assay was used to investigate the possibility of the opioid system involved in food intake regulation of normal rats. When rats were treated with 5mg morphine per kg body weight, subcutaneously, the food intake of the rats for the first 2 hours was increased 125% of the control rats. The effect of morphine on food intake of male and female rats were greater when the morphine was injected at 10 : 00 a.m than that in the rats administered the morphine at 4 : 00 p.m. The morphine effect was not significant in older rats and female was more responsive than male rats. In morphine treated rats, opioid receptor density has exhibited 33% reduction as measured by the $^{3}H-naloxone$ binding assay with whole brain homogenate. These results indicate that the increase of food intake by morphine for 2 hours after the injection may be mediated through the opioid system in rat brain.

• Korean Journal of Environmental Biology
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• v.24 no.2 s.62
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• pp.112-118
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• 2006

We report mitochondrial cytochrome b (cyt b) genes from greenling Hexagrammos otakii (Jordan et Starks) and spotty belly greenling, H. agrammus (Temminck et Schlegel) within Hexagrammidae, two species of aquaculture importance. Of 489 bp of the cytochrome b gene, a little variation occurred between species (96% similarity). The pairwise distance (0.0342) between greenling and spotty belly greenling in term of the Neighbor-joining method indicated that two species was close in molecular phylogenetic consideration. These findings are applicable to aquaculture, fisheries genetics and molecular phylogenetics in the genus Hexagrammos.

• Korean Journal of Medicinal Crop Science
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• v.3 no.2
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• pp.77-80
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• 1995

This study was carried out to know the effect of air temperature on photosynthesis and growth of Korean Valerian (valeriana fauriei var. dasycarpa HARA). The results are as follows; 1. Photosynthesis of V fauriei had highly significant relation to temperature in a quadratic regression mo­del, from which the optimum temperature for the plant growth were estimated to be $17.7^{\circ}C$. During the day­time in the field condition, the photosynthesis rate was highest at 9 a.m, then reduced to minimum at 2 p.m., and increased again thereafter. 2. Number of stomata was about $25/mm^2$ on the upper side and $85/mm^2$ on the lower side of the leaf, and the size was $21{\sim}30/{\mu}m$ in diameter. 3. A highly significant quadratic regression was noted between temperature and leaf width or root weight of V. fauriei. It was estimated from the regression equation that the optimum temperature for root growth was $20.3^{\circ}C$.

• Korean Journal of Medicinal Crop Science
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• v.2 no.2
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• pp.162-167
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• 1994

This study was carried out to investigate the compositions of fatty acids, inorganic components and volatile organic acids from Korean valerian roots, Valeriana fauriei var. dasycarpa Hara and Valeriana officinalis var. latifolia Miq. The contents of total lipids ranged from 3.7 % to 4.5% and the major fatty acids were linoleic, linolenic and palmitic acid. Ash contents ranged from 4.3% to 6.3%. and the contents of Na, Fe, Zn and Cu showed some quantitative differences depending upon grown region or species. Fourty components were identified from acidic fraction of dichloromethane extract of V. fauriei var. dasycarpa Hara, of which the major components were 3-methyl butanoic, dimethoxy-2-propenoic. 3, 4-dimethoxy benzoic and 3-methyl pentanoic acid.

• Korean journal of applied entomology
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• v.13 no.4 s.21
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• pp.251-253
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• 1974

Grain losses due to rodents are annually estimated to be about twenty percent of the whole grain production in Korea. The brown rat (Rattus norvegicus), the roof rat (Rattus rattus), the house mouse (Mus musculas) and the striped fold mouse (Apodemus agrarius) are primary species among eleven species found in the country. Rodent control has been conducted by the government since 1962. As for the poison. anticoagulant was used at first, but no satisfactory results were obtained due to limited funds, Since 1970, zinc phosphide has been introduced for the national campaign, but the degree of efficiency have been decreased year by year becaue of increased poison shyness. In order to overcome this problem, the author has improved 2inc phosphide effectiveness by the microcapsuling method with paraffin wax which increase intake of poison by masking the taste and delaying the onset of symptom. This method can be used efficiently for national campaign in future. However, more attention to this problem, more resarch, training and funding are required for the development of rodent control in Korea.