• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.717-731
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• 2011

To clarify relationships between the abundance and biological characteristics of Pacific salmon Oncorhynchus spp., we analyzed spatiotemporal changes in fork length, body weight, and an index of relative abundance (catch per unit effort, CPUE) for pink salmon (O. gorbuscha), chum salmon (O. keta), and sockeye salmon (O. nerka) collected by research gill-nets from the T/V Oshoro-maru and the T/V Hokusei-maru of Hokkaido University in the North Pacific during 1953-2007. Populations of each species were distributed throughout the western Bering Sea, eastern Bering Sea (EB), western North Pacific (WNP), central North Pacific (CNP), eastern North Pacific (ENP), and Okhotsk Sea. Since 1970, the average body size of chum salmon at ocean ages 0.3-0.4 has generally declined in the WNP and CNP. However, the average body sizes of sockeye and pink salmon have not shown temporal changes. Chum salmon showed significant negative (positive) correlations between CPUE and body size for populations in CNP (ENP) at ocean ages 0.2-0.3 (age 0.1) for both sexes. In general, sockeye salmon also showed significant negative (positive) correlations between CPUE and body size for populations in the EB at ocean ages X.2-X.3 (age X.1) for both sexes, except in CNP at age 2. Our results suggest that better growth by chum and sockeye salmon in the early periods of their ocean life histories might produce higher abundance. This higher abundance, which might also be affected by overlapping distributions among Pacific salmon species and populations in certain seas, in turn appears to cause density-dependent declines in growth in the following ocean life history period due to the limited carrying capacity of the seas. To understand complex dynamics in Pacific salmon species in the North Pacific Ocean, research on interactions among species and populations is needed.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.341-344
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• 2005

Courtship behavior of the sweet potato leaf worm, Aedia leucomelas L. (Lepidoptera: Noctuidae) was observed under laboratory condition. Behavior of antennal Probing and wing fanning in presence of opposite sex was observed in dark room. Both male and female exhibited similar behavior, fanning wing and raising antenna before male flew toward female. Some of moths began raising antenna 20 minutes into scotophase, and 20 minutes later both sexes started to exhibit spectacular behavior, fanning the wings intermittently in high frequency as if producing sound for attracting opposite sexes. They began mating about one day after emergence and mating activity was peaked from 4 to 6 days after emergence. Multiple mating was observed and the copulation lasted 207 minutes in average. There was an evidence that female emit sexual communication signal and male respond to it, and it seemed that the sound production is possibly a part of the courtship behavior of sweet potato leaf worm.

• Journal of Oriental Medical Thermology
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• v.8 no.1
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• pp.64-69
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• 2010

Purpose : This study was designed to investigate about symptoms named 'San(疝)', because almost no paper associated with San in Korea since the 1990s. Methods : Watch an overview of San with the Tonguibogam based. Results : In the Tonguibogam. according to the Zhang Ja-wha's classification. symptoms named 'San(疝)' are classified into seven kinds. As discussed in the Nephrology of Oriental Medicine, part of the Andrology, symptoms named 'San(疝)' are classified into three kinds. (1) San associated with reproductive organs. (2) San associated with pain (3) San associated with protrusion. The symptoms of San usually appears in the external genitalia and lower abdomen in both sexes can. The symptoms are called 'San(疝)' to the male and 'Ga' to the female. In the modern Obstetrics and Gynecology of Oriental Medicine. women's 'San' involves both 'San(疝)' and 'Ga'. San includes genital protrusion, but not includes vaginal hemia. It also includes genital edema, genital pruritus, genital herpes and bleeding after vaginal sex. San can be raised by many causes. The causes are damages by Coldness(傷寒), Damp-heat(濕熱), Serious distress(思慮過度) and Excessive sexual activity(房勞過多). The treatment for this symptoms is elimination of Dameum(痰飮). Jeokchwi(積聚) and Blood stasis(瘀血). Conclusion : The symptoms of San usually appears in the external genitalia and lower abdomen in both sexes can. The symptoms are called 'San(疝)' to the male and 'Ga' to the female.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.162-173
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• 2015

The current study analyzed the home range size of the Common Kestrel (Falco tinnunculus) by observation using the natural markings in the suburban area of Busan from December 2009 to May 2010. In all, 26 individual kestrels were observed in the study area, of which 14 individual kestrels were frequently observed (more than five times) and 12 were observed less frequently (less than five times). Mean home range sizes of the 14 frequently observed kestrels were estimated using two different methods (minimum convex polygon (MCP) method and fixed kernel (FK) method): 34.49 ha(2.74-163.96 ha) by 100% MCP, 41.35 ha(3.54-99.02 ha) by the 95% FK, 14.33 ha(0.20-31.57 ha) by the 75% FK and 5.75 ha(0.52-14.74 ha) by the 50% FK. The mean home range size was larger for males than for females estimated at 51.50 ha(15.04-163.96 ha) and 11.80ha(2.74-24.48 ha), respectively, by the 100 % MCP method and 8.02 ha(2.38-14.74 ha) and 2.72 ha (0.52-4.28 ha), respectively, by the 50 % Fixed Kernel method. The home range sizes by sexes in breeding pairs differed during the wintering and breeding seasons; the sizes decreased among females but increased among males during the breeding season. Such differences of home range sizes between sexes could be attributed to parental role division during the breeding season. Females stay in the nest or next to it during laying, incubating, and feeding activities, and males go far away from their nest sites to forage areas for their fledglings for most of the breeding period.

• International Journal of Industrial Entomology and Biomaterials
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• v.27 no.2
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• pp.243-264
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• 2013

Antheraea mylitta Drury is a commercial silk producing forest insect in India and Xanthopimpla pedator Fabricius is its larval-pupal endoparasitoid, which causes pupal mortality that affects seed production. Effects of host plants, rearing season and their interactions on parasitic behaviour of X. pedator were studied here, as influence of these factors on biological success of X. pedator is not known. Seven forest tree species were tested as food plants for A. mylitta, and rate of pupal parasitization in both the rearing seasons were recorded and analysed. Results showed that rearing season and host plants significantly affected the rate of pupal parasitization in both the sexes. Pupal mortality was found significantly higher (14.52%) in second rearing season than the first (2.89%). Likewise, host plants and rearing seasons significantly affected length, diameter, and shell thickness of cocoons in both sexes. Out of all infested pupae, 85.59% were found male, which indicated that X. pedator chooses male spinning larva of A. mylitta for oviposition, but we could not answer satisfactorily the why and how aspect of this sex specific parasitic behaviour of X. pedator. Multiple regression analysis indicated that length and shell thickness of male cocoons are potential predictors for pupal parasitization rate of X. pedator. Based on highest cocoon productivity and lowest pupal mortality, Terminalia alata, T. tomentosa, and T. arjuna were found to be the most suitable host plants for forest based commercial rearing of A. mylitta in tropical forest areas of Uttarakhand state, where it has never been reared earlier. Sex and season specific interaction of X. pedator with its larval-pupal host, A. mylitta is a novel entomological study to find out explanations for some of the unresolved research questions on parasitic behaviour of X. predator that opens a new area for specialised study on male specific parasitization in Ichneumonidae.

• Korean Journal of Cleft Lip And Palate
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• v.4 no.2
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• pp.19-27
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• 2001

This study was performed to determine the prevalence of hypodontia and hyperdontia of permanent teeth among Korean schoolchildren, and to compare differences in the prevalence between Korea, other country, and other ethnic groups. The sample consisted of 346 girls aged 6.9～0.3 yr and 375 boys aged 6.8～0.4 yr on whom a panoramic radiograph was taken at Yeonchun-Gun community in Korea. The prevalence of congenitally missing teeth (third molars excluded) was 6.7% in boys and somewhat higher, 9.5% in girls, and 8.0% for both sexes combined. On the average, number of missing teeth per affected child was 1.9 teeth. The most commonly congenitally missing teeth were the mandibular second premolar (32.7%), followed by the mandibular incisor (28.7%), the maxillary second premolar (16.7%), and the maxillary lateral incisors (10.2%). The prevalence of supernumerary teeth was 2.1 % in boys, 1.4% in girls, and 1.8% for both sexes combined. The most common supernumerary teeth were the mesiodens (76.9%), followed by the supernumerary premolar (23.1 %). The affected male-female ratio was 1.6: 1.0. The prevalence of congenital missing teeth in this study was similar to in studies of Japanese, Danish, American and German. The frequency of hyperdontia was lower in this study than in studies of Chinese children, Japanese and American.

• Journal of the korean academy of Pediatric Dentistry
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• v.1 no.1
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• pp.41-47
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• 1974

The dental caries survey of "K" primary school children was performed twice for one year interval and evaluated the transitional trend of dental caries prevalences. The number of children surveyed at the first year, 1973, was 819 boys and 653 girls; and the second year, 1974, was 815 boys and 661 girls aged 6 to 12. Under this survey, the following results were detected: 1. The average df person rate in deciduous teeth was increased by 7.52% in boy, 5.59% in girl and 6.65% of both. 2. The average df Index in deciduous teeth was increased by 0.13 in boy, 0.04 in girl and 0.1 of both. The average dt Index was decreased by 0.59 in boy, 0.64 in girl and 0.61 of both. The average ft Index was increased by 0.73 in boy, 0.68 in girl and 0.71 of both. 3. There showed no significant differences in DMF person rate between 1973 and 1974. 4. The DMFT Index of the permanent teeth was decreased by 0.19 in boy, and increased by 0.22 in girl. There showed no significant differences in both sexes between 1973 and 1974. The average DT Index was decreased by 0.43 in boy, 0.03 in girl and 0.31 of both. The average FT Index was increased by 0.23 in boy; 0.35 in girl and 0.29 of both. The average MT Index showed no significant differences in both sexes between 1973 and 1974.

• Korean Journal of Health Education and Promotion
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• v.20 no.4
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• pp.51-65
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• 2003

Objectives： To examine the regional mortality differences in The Republic of Korea according to geographic location. Methods： All 232 administrative districts of the Republic of Korea in 1998 were studied according to their geographic locations by dividing each district into three categories； "metropolis," "urban," and "rural". Crude mortality rates for doth sexes from total deaths as well as the three major causes of death in Korea (cardiovascular disease, cancer, and external causes) were calculated with raw data from the "1998 report on the causes of death statistics" and resident registration data. Standardized mortality ratios (SMR) were calculated using the indirect standardization method. Poisson regression analyses were performed to examine the effects of geographic locations on the risk of death. To correct for the socioeconomic differences of each region, the percentage of old ($\geq$ 65 years old) population, the number of privately owned cars per 100 population, and per capita manufacturing production industries were included in the model. Results： Most SMRs were the lowest in the metropolis and the highest in the rural areas. These differences were more prominent in men and in deaths from external causes. In deaths from cancer in women, the rural region showed the lowest SMR. In Poisson regression analysis after correcting for regional socioeconomic differences, the risk of death from all causes significantly increased in both urban (OR＝1.111) and rural (OR＝1.100) regions, except for rural women, compared to the metropolis region. In men, the rural region showed higher risk (OR＝1.180) than the urban region (OR＝1.l51). For cardiovascular disease and cancer, significant differences were not found between geographic locations, except in urban women for cardiovascular disease (OR＝1.151) and in rural women for cancer (OR＝0.887), compared to metropolis women. In deaths from external causes, the risk ratios significantly increased in both urban and rural regions and an increasing tendency from the metropolis to the rural region was clearly observed in both sexes. Conclusions： Regional mortality differences according to geographic location exist in The Republic of Korea and further research and policy approaches to reduce these differences are needed. to reduce these differences are needed.

• Archives of design research
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• no.16
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• pp.77-86
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• 1996

fhe purpose of lhlS study was to inves,igate ,he color preference of pees among Korean and Japanese Lnrversity students groups. Looking at a color chart contammg (is colored chips arranged sequentlally by hue and tone. the subjects from two countries were asked to choose their five most hlghly preferred colors and five least preferred colors. The data was classifed by hues and tones and then both sexes. The results were analyzed by comparison of the general orders of preference, and comparison of the selected colors by hues and tones and both sexes. The correlation of color preference in two countries was also studled uSlng Pearson's product moment correlatlOn cod ficren t. The results of this study were summaried as follows: 1. The most preferred color in two countries was vivid blue, and the least preferred color in two countries was grayish brown. 2. The most prefered hues in each countries were purple blue in Korea and blue in Japan. The least preferred hue in two countries was yellow red. 3. The most preferred tone in two countries was vivid and least preferred tone in two countries was grayish. 4. The correlation of the color preference between two countries was studied usmg Pearson's product moment correlation coefflCient for both hues and tones. I, indicated strong correlation in tones than in hues.

• Toxicological Research
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• v.33 no.4
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• pp.333-342
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• 2017

Ethyl formate, a volatile solvent, has insecticidal and fungicidal properties and is suggested as a potential fumigant for stored crop and fruit. Its primary contact route is through the respiratory tract; however, reliable repeated toxicological studies focusing on the inhalation route have not been published to date. Therefore, the present study was conducted to investigate the safety of a 90-day repeated inhalation exposure in rats. Forty male and 40 female rats were exposed to ethyl formate vapor via inhalation at concentrations of 0, 66, 330, and 1,320 ppm for 6 hr/day, 5 days a week for 13 weeks. Clinical signs, body weights, food consumption, urinalysis, hematologic parameters, serum chemistry measurements, organ weights, necropsy, and histopathological findings were compared between the control and ethyl formate-exposed groups. Locomotor activity decreased during exposure and recovered afterward in male and female rats exposed to 1,320 ppm ethyl formate. Body weight and food consumption continuously decreased in both sexes exposed to 1,320 ppm ethyl formate from week 1 or 3 compared with the control values. The increases in adrenal weight and decreases in thymus weight were noted in both sexes exposed to ethyl formate at 1,320 ppm. Degeneration, squamous metaplasia of olfactory epithelium in the nasopharyngeal tissue, or both were noted in the male and female rats at 1,320 ppm and female rats at 330 ppm ethyl formate. Taken together, our results indicate that ethyl formate-induced changes were not observed in male and female rats at 330 and 66 ppm, respectively. This indicates that exposure to ethyl formate at concentrations below 66 ppm for 90 days is relatively safe in rats. This is the first report of a full-scale repeated inhalation toxicity assessment in rats and could contribute to controlling occupational environmental hazards related to ethyl formate.