• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.21 no.1
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• pp.41-61
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• 1985

The purse-seine fishery is very important in the coastal fishery of Korea and the main fish species of this fishery are mackerals and also the main fishing grounds are Tushima Current region, To investigate the relationship between the fishing grounds of mackerels and oceanographic condition, the distribution of mean catches of mackerals of each size (1974~1982) was firstly examined and the oceanographic observation carried out in eastern and western area of Cheju island, being main fishing grounds, in July and October, 1983. The results are as follows: The main fishing grounds of mackerals were also in the Tsushima Current region in southern sea of Korea and the season of the good catches are in May and September to October. The small and medium size of mackerals of which the body lengths are 27 cm to 31 cm, about 2-3 ages, occupied about 90% but the smaller size mackerals of which body lenth is 22 cm (1 age)were about 40 to 70% in February to March. The locations of seasonal fishing grounds could founded by 15$^{\circ}C$ isotherm which indicates the Tsushima Current Water. With trace of this isotherm it was founded that the fishing grounds near the Korean Strait than that of south of Cheju island moves faster northward and/or later southward. The main fishing grounds eastward and westward of Cheju island were the front areas formed between the Tsushima Current Water and the southern coastal water of Korea or Yellow Sea Bottom Cold Water. And also the distributions of transparences, water colors and the penetration of sun light of this fishing grounds were similar to that of the temperature, the salinity or volume of planktonic organism.

• Korean Journal of Poultry Science
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• v.14 no.1
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• pp.39-53
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• 1987

A total of 1,440 White Leghorn pullets hatched in summer and winter, aged 20 to 72 weeks were fed 9 rations differing in dietary protein (13, 15 and 17%) and energy (2,500, 2,700 and 2,900 kcal/kg) levels for a period of 52 weeks in order to evaluate the optimum dietary energy and protein levels for laying hens. As metabolizable energy level increased from 2,500 to 2,900 kcal/kg of feed egg production, daily feed and protein intake and egg shell quality decreased, but reverse was true for the daily energy intake, energy requirement and feed cost per kg egg, body weight gain, nutrients utilizability and abdominal fat accumulation, Egg weight, viability and egg yolk Pigmentation were not affected by the dietary energy level. On the other hand, as dietary protein level increased from 13 to 17%, egg production, egg weight, daily protein intake, protein requirement per kg egg and body weight gain icreased, but daily feed and energy intake, feed and energy requirement per kg egg, egg yolk pigmentation and dry matter utilizability decreased, and no significant difference in the feed cost per kg egg, viability and egg shell quality was observed among dietary protein levels. However: the hens fed 15% and 17% Protein diets did not show significant differences in egg production, egg weight and body weight gain. For the entire laying period of 52 weeks, metabolizable energy level of 2,500 kcal/kg of feed and 15% dietary protein level were considered to be adequate to support the optimum productivity.

• Korean journal of applied entomology
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• v.24 no.2 s.63
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• pp.61-64
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• 1985

This study was carried out to investigate the seasonal occurrence and developmental periods of Rice stem maggot (RSM), Chlorops oryzae Matsumura, at laboratory and in the fields in $1980{\sim}1982$. RSM occurred three generations a year. Peak of the first, second, and third generation was middle to late May, early July and middle September. Longevity of the first generation adult averaged 18.9 days and the oviposition was 50 eggs per fly. The eggs, larval and pupal period was 7, 25, 14 days respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.423-435
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• 1984

The reproductive cycle of the small filefish, Rudarius ercodes was investigated based on the annual variations of gonadosomatic index(GSI) and hepatosomatic index(HSI) by electronic and photic microscophy. The specimens used were collected at the coastal area of Benden island, Sizuokagen, Japan, from September 1982 to August 1983. GSI began to increase from March, starting season of longer daylength and higher water temperature, and reached the maximum value between June and August. It began to decrease from September with the lowest value appearing between November and February without any evident variation. The annual variations of HSI were not distinct in male filefish and were negatively related to GSI in female : HSI decreased in the summer season when the ovary was getting mature and reached the maximum in the winter season when the ovary was getting retrogressive. The ovary consisted of a pair of saccular structure with numerous ovarian sacs branched toward the median cavity. Oogonia divided and proliferated along the germinal epithelium of the ovarian sac. Young oocytes with basophile cytoplasm showed several scattering nucleoli along the nuclear membrane. when the oocytes growing to about 300 ${\mu}m$, nuclear membrane to disappear with nucleus migrating toward the animal pole. The regions of protoplasm were extremely confined within the animal hemisphere in which most of cytoplasms were filled with yolk materials and oil drops. After ovulation, residual follicles and growing oocytes remaining in the ovarian sacs degenerated. But perinucleatic young oocytes without follicles formed were not degenerated, and growing continuously still in the next year. Mitochondria and endoplasmic reticula in the cytoplasm remarkably increased with oocytes maturing and yolk accumulating. Those were considered to be functionally related to the yolk accumulation. Five or six layers of possible vitellogenin, oval-shaped disc structures with high electron density, appeared in the apex of follicular processes stretching to the microvilli pits of mature oocytes. Testis consisting of a pair of lobular structures in the right and left were united in the posterior seminal vesicle, Cortex of testis was composed of several seminiferous tubules, and medulla consisting of many sperm ducts connected with tubules. Steroid hormone-secreting cells with numerous endoplasmic reticula and large mitochondria of well developed cristae were recognized in the interstitial cells of the growing testis. Axial filament of spermatozoon invaginated deeply in the central cavity of the nucleus and the head formed U-shape with acrosome severely lacking, mitochondria formed large globular paranuclei at the posterior head, and microtubular axoneme of the tail represented 9+9+2 type. The annual reproductive cycles could be divided into five successive stages : growth(March to July), maturation(May to September), Spawning(mid May to early October) and resting stages(October to February). The spawning peak occurred from June to August.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.409-416
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• 1987

The object of this study was to investigate the differences in dry matter production, physiological characteristic and grain yield of soybean (Glycine max (L.) Merr.) as affected by planting dates in southern region of Korea. This experiment was conducted using four planting dates and four varieties over 3 years (1982-1984). The different responses of soybean varieties to different temperature and daylength, days from planting to flowering were ranged from 43 to 55 days when planted on May 10 long daylength and low temperature condition. Flowering duration was ranged from 12 to 27 days and 9 to 13 days for the plantings made on May 10 and July 9, respectively. Therefore, it was the shortest under the short daylength and high tempera-ture condition. It also appeared that the later planting caused the lower dry matter weight and leaf area index which resulted in lower grain yield. But grain yield was not directly correlated with the unbalance of Xink/Source Ratio and the lodging from excessive vegatative growth. The grain yield was the highest in May 30 and the lowest in July 9 planting: it was ranged from 2.26 to 2.55 t/ha in the former and 0.85 to 1.20 t/ha in the latter, respectively. The increase in yield was depended on the increase in the number of pods per plant, the number of seeds per pod and the seed weight. The distribution ratio of dry matter to leaves was the hightest at the sixth trifoliolate leaf stage and gradually declined thereafter in all planting dates, and it also appeared that the later planting, the lower the ratio of dry matter to leaves.

• Journal of Chest Surgery
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• v.29 no.9
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• pp.945-950
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• 1996

Twelve patients with left ventricular-right atrial shunt (LV-RA shunt) underwent surgical correction be- tween April 1982 and March 1995. Seven patients were male and five patients were female. Age ranged from 3 to 26 years with mean age of 8.5 years. On the preoperative chest PA views, increased pulmonary vascularity was noted in 3 cases and enlargement of right atrium in 4 cases. The mean preoperative cardiothoracic ratio was 0.59. Echocardiographic studies were obtained in 9 patients and the preoperative echocardiographic diagnoses were LV-RA shunt in 2 cases, ventricular septal defect (VSD) in 6 casei, and atrial septal defect (ASD) in 1 case. The preoperative ngiographic diagnoses which were obtained in all patients were LV-RA shunt in 5 cases, VSD in 5 cases, ASD in 1 case, and VSD with ASD in 1 case. The descriptions of defect of LV-RA shunt according to intraoperative findings were supravalvular defect in 5 cases(42%), infravalvular defect in 4 cases (33%), and combined defect in 3 cases (25%). Associated anomalies of tricuspid valve in 4 cases of infravalvular defect were perforation (3 cases) and cleft (1 case). Primary closure of the septal defect was performed through the right atriotomy in all but one patient. There was no operative death. One patient underwent reoperation because of the residual interventricular shunt. All patients have been in good condition.

• Journal of Preventive Medicine and Public Health
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• v.16 no.1
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• pp.13-18
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• 1983

This study was attempted to define epidemiologically the possibility and the magnitude of sexual transmission of HBV in Korea. Two groups of prostitutes; one group (309) deals with Koreans, the other group (126) deals with American soldiers stationing in Korea, were tested for the presence of HBsAg and anti-HBs. The prevalence rate of HBsAg or anti-HBs was significantly higher in prostitutes who deal with Koreans (41.7%) than in prostitutes who deal with American soldiers (30.2%) (p<0.025). Among the prostitutes who deal with American soldiers, there was no appreciable difference in the prevalence rate of HBsAg or anti-HBs by the duration of prostitution. However, among the prostitutes who deal with Koreans, the prevalence rate was increased with the duration of prostitution, although it did not reach the statistically significant level (p=0.12). There was no remarkable association between the prevalence rate of HBsAg or anti-HBs and educational level, history of operation or history of transfusion. The data support the possibility of sexual transmission of viral hepatitis B but it seems seems sexual transmission does not contribute significantly to the prevalence rate of HBsAg or andi-HBs in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.305-315
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• 1983

A survey was carried out from July to December in 1979 and 1982 for the investigation of oceanographic conditions and phytoplankton in Seogwipo coastal area. Although a peculiar coastal sea water is formed by in flowing of fresh water, this is developed mainly in summer and disappeared or weakened in its strength after November. However, this coastal sea water covers only the surface while in mid and bottom layer open sea water is approached to the coast. Therefore, coastal and open sea water appears simultaneously in narrow sea area. Mean values of nutrient concentrates on surface layer during investigating period were $3.72{\sim}16.34{\mu}g-at/l$ in silicate, $1.98{\sim}5.53{\mu}g-at/l$ in nitrate and $0.34{\sim}0.90{\mu}g-at/l$ in phosphate. These showed slight differences among places but in general coastal side were lower than open sea side. Phosphates which is the lowest in concentrates among nutrients in Seogwipo coastal area shows almost similar value with Jinhae Bay but higher than open sea water around 10 mile south of Seogwipo. In general, seasonal changes of nutrients in investigating period shows a tendency of the lowest in October, increasing in November, and again slight decrease in December. As a phytoplankton fauna, 48 species, 1 variety and 2 breeds of Diatoms, 29 species, 3 varieties and 1 breed fo Dinoflagellates, and 1 species each of Chroococcus and Trichoceratium were found. Monthly predominant species are all neritic: Rhizosolenia sp. and Ceratium sp. in August, Chaetoceros sp., Ceratium sp. and Peridinium sp. in September, Astrionella sp. and Peridinium sp. in October, Astrionella sp., Navicula sp. and Chaetoceros sp. in November Among these, Rhizosolenia alata f. gracillima in August and Astrionella gracillima in November are remarkable predominant.

• Korean Journal of Environmental Agriculture
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• v.3 no.1
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• pp.36-44
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• 1984

Waters, sediments and crucian carps samples collected bimonthly from Nakdong river during- the period of August 1982 to June 1983 were analyzed for organophosphorus pesticide residues by GLC equipped with a flame photometric detector. Among the environmental samples, IBP, diazinon, phenthoate, parathion, malathion and fenitrothion residues were found only in waters and crucian carps and sediments samples were devoid of the residues. In addition, seasonal variations of the residues in waters and crucian carps were observed. Waters and crucian carps samples collected in August, when pesticides are generally in great demand, contained all the organophosphorus pesticide residues while no organophosphorus were detected in waters and crucian carps samples collected in February, April or December. The most abundant residues in the two environmental samples were diazinon and IBP and residue levels of parathion, malathion and fenitrothion were found extremely low.

• The Korean Journal of Mycology
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• v.10 no.3
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• pp.101-110
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• 1982

This study has been carried out for the publication of colored illustrations of Korean fungi. The fresh fungi of Ascomycetes were collected and photographed, for the most part, at Gwangneung, Kyonggi Province, Mt. Yongmun in Kyonggi Province, Mt. Sokri in Chungcheong Province, Mt. Jiyee in Kyeongsang Province, Mt. Mudeug in Jeonra Province, and Mt. Hanra in Jeuju Island from July 1, 1981 to June 31, 1982. These higher fungi were made into colored slides and dried specimens, then classified. According to the investigated result, colored slides and classification for the common and new to Korea 101 species were completed among 620 spp. which were known all of the fungi in Korea. They were included 10 oders, 19 families, 51 genera and 101 species. Their world distributions were investigated. Twenty six species of them, that is, Peziza vesiculosa, Rhizina inflata, Gelasinospora longispora, Sordaria fimicola, Cantharcmyces exiguus, Dichomyces biformis, D. furcifer, D. homalotae, D. hybridus, D. vulgatus, Dioicomyces anthici, Enathromyces indicus, Laboulbenia borealis, L. brachconychi, L. cristata, L. exigua, L. fusciculata, L. filifera, L. flagellata, L. rougetii, L. tachys, L. vulgaris, L. yoshidai, Rickia ancylopi, R. papuana and R. peyerimhoffii were found to be new in Korea. In addition their common names and descriptions prepared. According to study plan, this paper pressed only one page in colored plate among 101 species.