• Economic and Environmental Geology
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• v.22 no.4
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• pp.303-314
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• 1989

The electrum-silver-sulfide mineralization of the Geojae island area was deposited in three stages (I, II, and carbonate) of quartz and calcite veins that crosscut Late Cretaceous volcanic rocks and granodiorite(83 m.y.). Stages I and II were terminated by the onset of fractunng and breCCIation events. Fluid inclusion data suggest that the gold-sulfide-bearing stages I and II each evolved from an initial high temperature( near $370^{\circ}C$) to a later low temperature(near $200^{\circ}C$). Each of those stages represented a separate mineralizing system which cooled prior to the onset of the next stage. The relationship between homogenization temperature and salinity in stages I and II suggests a complex history of boiling, cooling and dilution. Evidence of boiling indicates a pressure of < 100 bars, corresponding to a depth of 500 to 1,250m assummg hthostatlc and hydrostatic pressure regimes, respectively. Fluid inclusion and mineralogical evidence suggest that the electrum-silver mineralization was deposited at a temperature of $220-260^{\circ}C$ from ore fluids with salinities between 1.9 and 8.1 equivalent wt.% NaCl. Total sulfur concentration is estimated to be $10^{-3}$ to $10^{-4}$ molal. The estimated $fs_2$ and $fo_2$ range from $10^{-11.8}$ to $10^{-14}$ atm and $10^{-35}$ to $10^{-36}$ atm, respectively. The chemical conditions indicate that the dominant sulfur species in the ore forming fluids was a reduced form($H_2S$). Rapid cooling and dilution of ore-forming fluids by mixing with less-evolved meteoric waters led to gold-silver deposition through the breakdown of the bisulfide complex($Au(HS)_2$) as the activity of $H_2S$ decreased.

• Journal of Conservation Science
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• v.25 no.1
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• pp.101-114
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• 2009

Potsherds and kilns of the AD 3th century excavated from Gundong and Majeon sites, Korea were studied to investigate the production techniques and provenance of potsherds and kilns on the pastes. For potsherds, kilns blocks and in-situ paleo-soils, provenance of raw materials were estimated through mineralogy and geochemistry, while production technique and thermal feature of kilns were investigated through observation of textures and compositions as well as firing experiment on paleo-soils. As a result of study, potsherds and kilns were found to have similar mineralogical compositions as the neighboring paleo-soils and to have same evolution path with that of geochemistry. The potsherds were divided into 3 groups according to firing temperature and production technique. Group 1 consists of reddish stamped pattern pottery with loose textures, which has many pores and contains many iron oxides. Its temper is less than about 0.5mm, and was probably fired between 700 to $800^{\circ}C$. Group 2 contains ash to grayish blue stamped pattern pottery, which has vitrified texture and few pores. Its temper is less than about 0.5mm, and was probably fired from 900 to $1,000^{\circ}C$. However, some potsherd belongs to the group 2 in terms of features for temper and pastes, but it was probably fired over $1,100^{\circ}C$. Group 3 contains reddish and grayish stamped pattern pottery. It has vitrified matrix, few pores and temper consists of polycrystalline quartz and feldspar over 2mm, and it was probably fired around $1,000^{\circ}C$. The kiln had experienced temperature from 600 to $700^{\circ}C$ on the wall, from 900 to $1,000^{\circ}C$ on the bottom, suggesting the function of high temperature firing.

• Journal of the Korean Child Neurology Society
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• v.26 no.4
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• pp.227-232
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• 2018

Purpose: Febrile seizure (FS) is the most common type of seizure in children between 6 months to 5 years of age. A family history of febrile seizures can increase the risk a child will have a FS. Yet, prevalence of FS regarding external environment has not been clearly proved. This study attempts to determine the association between prevalence of FS and weather. Methods: This study included medical records from the Korea National Health Insurance Review and Assessment Service. Data were collected from 29,240 children, born after 2004, diagnosed with FS who were admitted to one of the hospitals in Seoul, Korea, between January 2009 and December 2013. During the corresponding time period, data from the Korea Meteorological Administration on daily monitoring of four meteorological factors (sea-level pressure, amount of precipitation, humidity and temperature) were collected. The relationships of FS prevalence and each meteorological factor will be designed using Poisson generalized additive model (GAM). Also, the contributory effect of viral infections on FS prevalence and weather will be discussed. Results: The amount of precipitation was divided into two groups for comparison: one with less than 5 mm and the other with equal to or more than 5 mm. As a result of Poisson GAM, higher prevalence of FS showed a correlation with smaller amount of precipitation. Smoothing function was used to classify the relationships between three variables (sea-level pressure, humidity, and temperature) and prevalence of FS. FS prevalence was correlated with lower sea-level pressure and lower humidity. FS prevalence was high in two temperature ranges (-7 to $-1^{\circ}C$ and $18-21^{\circ}C$). Conclusion: Low sea-level pressure, small amount of precipitation, and low relative air humidity may increase FS prevalence risk.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.449-470
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• 1984

The cercaria of Bacciger herengulae which is parasitized on the gonad of Solen strictus was investigated in order to reveal its entire life history. The area covered for the study was in the vicinity sea of Naechodo, the estuary of the Kum river in the western coast of Korea during the period of 1980-1983. Morphology and development as well as infection rates of sporocyst and cercaria within Solen strictus were examined. For accomplishing the objectives of this study, an artificial infection experiment and some investigations on the second intermediate host, the final host and the growing stages were also studied in both laboratory and natural habitat of Solen strictus. According to the study, it was revealed that the first intermediate hosts were Meretrix lusoria, Solen strictus, Tapes japonica and Laternula limicola, the second intermediate host was Palaemon (Exopalaemon) carinicauda and the final hosts were Konosirus punctatus and Harengula zunasi. A mature sporocyst which was found in the gonad of Solen strictus was $4.0-4.3{\times}0.2-0.21\;mm$ insize, and the cercaia with 27 pairs of setae, each seta consisting of 6 tufts, was $270{\times}147{\mu}m$ in body size and $550{\times}52{\mu}m$ in tail size. Oral sucker($52{\times}42{\mu}m$), pharynx, vental sucker and two testese were obviously seen within the cercaria. The excretory vesicles of cercaria were in V-shape and the flame cell were formula was expressed as 2[(3+3)+(3+3)]=24. The infection of cercaria in the first intermediate host, Solen strictus, was found throughout the year regardlless of the water temperature, and its mean infection rate was $9.67\%$ during the study period. The infection rate fluctuated with temperature, the highest being $28.0\%\;at\;28.0^{\circ}C$ water temperature in July and the lowest $2.4\%\;at\;19.5^{\circ}C$ in October, and it increased in proportion to the shell length on the host. But cercaria was not detected at below 4.0 cm in size of the host. Mature cercariae were found 6 months from May to October when water temperature was above $19.5^{\circ}C$. On the other hand, when water temperature was below $19.5^{\circ}C$, only immature cercariae and sporocysts were found. The cercariae were active for 35 hours and survived for 71 hours at $20^{\circ}C$, and 29 and 34 hours at $25^{\circ}C$ respectively, whereas the cercariae were inactive at less than $20^{\circ}C$ in water temperature. Cercaria, from Solen strictus, approached shrimp of 1-3 cm in body length as its second host. Then, it began to intrude in to the muscle of shrimp after 2-3 hours. The infected cercaria formed cyst after 7-8 hours, and became mature metacercaria. $420{\times}310{\mu}m$ in size, 15 days afer infection. The infection rate of metaceria to shrimp in the laboratory was highest, at $25^{\circ}C$ being $61\%$ and at $20^{\circ}C\;17%$. The infection rate of metacearia in shrimp was highest in the first abdominal segment, followed by cephalothorax, the second, and fifth abdominal segments, and in that order. Also, the infection rate of metacercaria in wild shrimp was high $9.6-11.1\%$ at $26.5^{\circ}C$ in June, and low $1.56-2.5\%$ at $28-29.5^{\circ}C$ from July to August. The infected shrimp with metacercaria was experimentally fed to Konosirus punctatus in the laboratory in order to know its final host. The metacercaria developed into the adult worm, $440-520{\times}310-360{\mu}m$ in size, within the intestine of Konosirus punctatus 20 days after infection. The adult worm was oval shape and $20-24{\times}11-20{\mu}m$ in size. The infection rate of adult worm to Konosirus punctatus and Harengula zunasi ranged 87.3 to $100\%$, the mean being $95.2\%$, regardless of the body length of their hosts. The infection rate was $100\%$ in June and July, but it decreased in September and October. The size and body structure of the trematode observed during the present study were well agreed with those ievestigated by Yamaguti(1938), thus, it may be concluded that the adult worm it identified as Bacciger harengulae.

• Clinical and Experimental Pediatrics
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• v.49 no.8
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• pp.839-844
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• 2006

Purpose : We studied clinical patterns of the febrile infants and children presenting to the Pediatric Emergency Department(ED) in the general pediatric population. Method : We analyzed 1,764 infants and children who had a history of measured body temperature of $38.3^{\circ}C$ or higher, before or after arrival at Pediatric ED of Ilsan Paik Hospital from September 2004 to August 2005. We analyzed their clinical patterns, such as the frequency of febrile illness, age distribution, monthly distribution, diagnosis. Result : The frequency of the febrile illness at Pediatirc ED was 19.9 percent (1,764/8,881 cases). The percentage of admission into hospital was 26.4 percent. The most common age group presenting to Pediatric ED with febrile illness was the 12-23 months group(22.8 percent) followed by the 4-11 months group and the 2 years group. In May, the most numerous patients presented to the Pediatric ED with febrile illness. The frequency of febrile illness was significant higher in the 'Spring & Summer group' compared to the 'Autumn & Winter group'. The ratio of male to femal was 1.4:1. The most common diagnosis was acute pharyngitis(42.5 percent), followed by acute gastroenteritis (15.3 percent), pneumonia(7.0 percent). Conclusion : The frequency of the febrile illness at Pediatirc ED was 19.9 percent. The most numerous patients visited Pediatric ED in May. And, the most common age group was 12-23 months. The proportion of non-urgent disease, such as acute pharyngitis, acute gastroenteritis, acute nasopharyngitis and acute bronchitis, was high. There is a need to educate parents and improve the medical system in Korea.

• Korean Journal of Ichthyology
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• v.2 no.2
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• pp.159-168
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• 1990

Parental fish of R. uyekii(Mori) were colleted from the Nakdong River, Korea. Artificial insemination was carried out 4 times during June using the same pair (a female 52.70 mm TL and a male 56.80 mm TL). Unfertilized eggs are nearly spindly, opaque yellow in colour, measuring about 3.20-3.50 mm in length, about 1.50-1.80 mm in breadth. Hatching began about 50 hours after insemination at water temperature of $16.5{\sim}18.5^{\circ}C$. The newly hatched larvae are 4.10-4.50 mm in total length(TL), with 29-30 myomeres. Nine days after hatching, the larvae averaged 8.40 mm in total length and caudal notochord flexed at $45^{\circ}$. Eighteen days after hatching, total length reached 8.90 mm. The part of the fin-fold of the future dorsal and anal fins became high. Twenty-eight days after hatching, total length was 9.35 mm. The caudal fin-rays began to fork into two branches. The increased number of melanophores appeared newly on the head dorsal and anal fin-rays. The larvae reached the juvenile stage at 50-60 days after hatching and attained 14.50-16.20 mm in total length, and all fin-rays was formed.

• Journal of Mushroom
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• v.18 no.3
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• pp.179-188
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• 2020

The oak mushroom (Lentinula edodes) is a popular edible mushroom that has long been cultivated and eaten throughout Northeast Asia (including Korea). Its taste and flavor are unique. Oak mushrooms are cultivated on logs and in sawdust. The cultivation period on logs is 4-5 years, while the cultivation period in sawdust is 6 months, which is rapidly driving a shift from log to sawdust based cultivation. In particular, the Sanjo 701ho cultivar of L. edodes is a mid-range to high-temperature variety that is widely known for its suitability for summer cultivation on sawdust in Korea. This study summarizes new developments and achievements in the oak mushroom industry in Korea, and details the cultivation history of Sanjo 701ho, its culturing characteristics, various demonstration tests, and the expansion of domestic varieties.

• Korean Journal of Veterinary Service
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• v.34 no.2
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• pp.167-178
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• 2011

Garlic (Allium sativum L.) has long history of reputed value and actual use for its medicinal, antimicrobial and pesticidal properties. This study was conducted to find possible developments to natural food preservatives and natural antimicrobials from garlic extracts. The antimicrobial activities of raw garlic extract, heat, pH, temperature against pathogenic bacteria were investigated. E. coli, S. Enteritidis, L. monocytogenes, and S. aureus exhibited antimicrobial activities at 20% garlic extract, but no antimicrobial activity was seen in E. faecium. Raw garlic extract and garlic extract heated for 2 min at $95^{\circ}C$ showed strong antimicrobial activities, but the antimicrobial activity of garlic extract heated for 10 min at $95^{\circ}C$ was much less. The antimicrobial activities of 50% garlic extract adjusted pH 4.0~7.0 showed much the same, but the antimicrobial activities decreased at pH 8.0 or higher. The antimicrobial activities by storage $-18^{\circ}C$ of garlic extract showed much the same. When five strains were cultured for 72 hr at $35^{\circ}C$ in the TSB containing 1~10% garlic extract, viable cell number of five strains were decreased to $10^0{\sim}10^4$ CFU/ml even at 1% or 2.5% (E. faecium) after 24 hr, but later increased to $10^4{\sim}10^9$ CFU/ml after 72 hr. When five strains were cultured for 21 day at $4^{\circ}C$ in the TSB containing 1%, 2.5%, 5%, and 10% garlic extract, viable cell number of E. coli, S. Enteritidis, and S. aureus were decreased to $10^3$, $10^0{\sim}10^2$, $10^1{\sim}10^4$ CFU/ml after 21 day, respectively, but L. monocytogenes and E. faecium increased to $10^8$ and $10^6$ CFU/ml after 21 day.

• Sleep Medicine and Psychophysiology
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• v.8 no.1
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• pp.59-66
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• 2001

Objectives: This study examined the effect of mood and personality characteristics on psychophysiological responses measured by a biofeedback system in a normal population. Methods: Fifty healthy volunteers without any history of medical or psychiatric illnesses participated in this study. We measured the Spielberger trait anxiety inventory, Beck depression inventory, and Eysenck personality questionnaires in these subjects. Using the J & J biofeedback system, we also measured skin temperature, electrodermal response, forearm and frontal electromyography (EMG)s in 3 experimental conditions of baseline, stress, and recovery phases. Results: Trait anxiety did not show any significant correlation with psychophysiological responses except stress response in forearm EMG levels(r=0.282, p<0.05). Depressed mood was negatively correlated with forearm EMG levels in baseline (r=-0.299, p<0.05) and recovery phases(r=-0.314, p<0.05). Subjects with relatively high levels of depressed mood showed different stress and recovery responses in frontal EMG levels compared with those with relatively low levels of depressed mood (F=4.26, p<0.05). Extroverted subjects showed higher levels of forearm EMG than introverted ones in stress phase. Conclusion: Mood and personality characteristics in healthy subjects are closely related with psychophysiological responses measured by a biofeedback system. We suggest that mood and personality characteristics should be considered as important variables in analyzing abnormal psychophysiological responses in some psychiatric patients.

• Economic and Environmental Geology
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• v.32 no.6
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• pp.561-573
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• 1999

Mesothermal gold deposits of the Heungdeok, Daewon and Ilsaeng mines in the Youngdong area occur in fault shear zones in Precambrian metamorphic rocks of central Sobaegsan Massif, Korea, and formed in single stage of massive quartz veins (0.3 to 3 m thick). Ore mineralogy is simple, consisting dominantly of pyrrhotite, sphalerite and galena with subordinate pyrite, chalcopyrite, electrum, tetrahedrite and native bismuth. Fluid inclusion data indicate that hydrothermal mineralization occurred at high temperatures (>240$^{\circ}$ to 400$^{\circ}$C) from $H_{2}O-CO_{2}(-CH_{4})$-NaCI fluids with salinities less than 12 wt. % equiv. NaC!. Fluid inclusions in vein quartz comprise two main types. These are, in decreasing order of abundance, type I (aqueous liquid-rich) and type II (carbonic). Volumetric proportion of the carbonic phase in type II inclusions varies widely in a single quartz grain. Estimated $CH_4$ contents in the carbonic phase of type II inclusions are 2 to 20 mole %. Relationship between homogenization temperature and salinity of fluid inclusions suggests a complex history of fluid evolution, comprising the early fluid's unmixing accompanying $CO_2$ effervescence and later cooling. Estimated pressures of vein filling are at least 2 kbars. The ore mineralization formed from a magmatic fluid with the ${\delta}^{34}S_{{\Sigma}S}$, ${\delta}^{18}O_{water}$ and ${\delta}D_{water}$ values of -2.1 to 2.2$\textperthousand$, 4.7 to 9.3$\textperthousand$ and -63 to -79$\textperthousand$, respectively. This study validates the application of a magmatic model for the genesis of mesothermal gold deposits in Youngdong area.