• Development and Reproduction
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• v.12 no.2
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• pp.169-181
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• 2008

Reproductive ecology of the silver pomfret, Pampus argenteus were investigated by histological observations and morphometric data. Samples were collected by the stow net at the coastal area of Jaun-Do, Muan-gun, Korea, from January to December, 2006. P. argenteus is dioecious, the ovary is composed of many ovarian lobules, showing a pair of saccular structure, and the testis is composed of many seminiferous lobules, showing a pair of lobular structure. From February (growing stage) to September (after spawning), monthly changes in the gonadosomatic index, hepatosomatic index, and condition factor in females and males showed similar patterns with the gonad developmental phases. Judging from the results of their indice, it is assumed that spawning in females and males occur from May to July. The reproductive cycle can be classified into five successive stages in females: early growing stage (February to March), late growing stage (March to April), mature stage (March to July), ripe and spent stage (May to July), and recovery and resting stage (July to February); in males, the cycle can be divided into four successive stages: growing stage (February to April), mature stage (March to June), ripe and spent stage (May to July), and recovery and resting stage (July to February). According to the frequency distributions of egg diameters in the breeding season, P. argenteus is presumed to be spring-summer spawning species and polycyclic species to spawn 2 times or more during one spawning season. Number of total eggs in absolute fecundity were proportional to body length and body weight, respectively. Number of total eggs in absolute fecundity per body weight were also proportional to the body length, but if the increase of body weight considerably increased, rather total eggs in relative fecundity decreased with the increase of body weight. Percentage of first sexual maturity of P. argenteus were over 50% in females and males of 12.1 to 15.0 cm in body length, and 100% for fishes over 18.1 cm in length. Therefore, both sexes were regarded to be sexually mature at one year of age.

• Korean Journal of Plant Resources
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• v.21 no.1
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• pp.1-4
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• 2008

The clonal variation in female flowering was studied in Larix leptolepis clone bank, consisting of 116 clones, for three years. The between-year variation was large; i.e. the percentage of flowering grafts and average number of flowering per graft were $28.4{\sim}67.2$ and $9{\sim}176$, respectively. Differences in flowering abundance among clones were large and statistically significant in all the years studied. The variance of flowering abundance among clones was increased when flowering was poor. The average of broad-sense heritability of flowering abundance was 0.52. The genetic gain(%G) was estimated at 57.4% when the upper 30% clones were selected. The clonal stability of flowering abundance was compared using average number of flowering and coefficient of variance value of each clone. The clones such as Gyeonggi 9(29), Kangwon 37(137), Chungnam 6(46), Chungnam 14(414), R11, R8 showed abundant flowering and high stability.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.4
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• pp.266-274
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• 1999

Vertical CTDT measurement at one point near tidewater glacier of fjord-head in Marian Cove, a tributary embayment of Maxwell Bay, South Shetland Islands was performed for 24 hours during the austral summer (January 21-22, 1998) to present water-column properties and SPM (suspended particulate matter) dispersal pattern in subpolar glaciomarine setting. Marian Cove shows three distinct water layers: 1) cold, freshened, and highly turbid surface plume in the upper 2 m, 2) warm, saline, and relatively clean Maxwell Bay water between 15-35 m in water depth, and 3) cold and turbid mid plume between 40-65 m in water depth. The surface plume is composed of silt-sized clastie particles mixed with flocculated biogenic detritus, and appears to originate from either supraglacial discharge by meltwater streams along the coast or water fall of ice cliff. Freshened and turbid mid plume consists exclusively of silt-sized clastic particles, resulting from subglacial discharge beneath the tidewater glacier. The disappearance of the two turbid plumes during the earlier period of measurement seems to be largely due to the breakup of the plumes by upwelling caused by strong easterly wind (> 8 m $sec^{-1}$). Thus, wind coupling over tidal effects regionally plays a major role in dispersal pattern of SPM as well as water exchange in Marian Cove.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.15-21
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• 2001

This study was conducted to investigate the immunomodulatory activities of proteoglycan extracted from cultured mycelia of Ganoderma lucidum IY009. The proteoglycan contained two polymer peaks, one was the higher MW peak of 2,000 kD and the other was low peaks of 12kD. To understand the part of strong pharmaceutical activity between two peak, the proteoglycan was separated by ultrafiltration and column chromatography and then examined the various pharmaceutical effects. High molecular weight fraction possesing high content of ${\beta}-linked$ glucan was exhibited high antitumor activity, against sarcoma 180 bearing ICR mouse. And also, anticomplementary activity was highly observed in high molecule fraction than low it fraction. When the raw 264.7 and murine peritoneal macrophage treated with low fraction, high fraction and other stimuli. The activities inducing tumor necrosis factor of the high factions were $2.2{\sim}2.5$ times stronger than that of low fraction.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.123-131
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• 2009

Purpose: We tested a sample of nuclear medicine workers at Korean healthcare institutions for internal contamination with radioactive isotopes, measuring concentrations and evaluating doses of individual exposure. Materials and Methods: The detection and measurement was performed on urine samples collected from 25 nuclear medicine workers at three large hospitals located in Seoul. Urine samples were collected once a week, 100~200 mL samples were gathered up to 6~10 times weekly. A high-purity germanium detector was used to measure gamma radiations in urine samples for the presence of radioactive isotopes. Based on the detection results, we estimated the amounts of intake and committed effective doses using IMBA software. In cases where committed effective doses could not be adequately evaluated with IMBA software, we estimated individual committed effective doses for radionuclides with a very short half life such as $^{99m}Tc$ and $^{123}I$, using the methods recommended by International Atomic Energy Agency. Results: Radionuclides detected through the analysis of urine samples included $^{99m}Tc$, $^{123}I$, $^{131}I$ and $^{201}Tl$, as well as $^{18}F$, a nuclide used in Positron Emission Tomography examinations. The committed effective doses, calculated based on the radionuclide concentrations in urine samples, ranged from 0 to 5 mSv, but were, in the majority of cases, less than 1 mSv. The committed effective dose exceeded 1 mSv in three of the samples, and all three were workers directly handling radioactive sources. No nurses were found to have a committed effective dose in excess of 1 mSv. Conclusions: To improve the accuracy of results, it may be necessary to conduct a long-term study, performed over a time span wide enough to allow the clear determination of the influence of seasonal factors. A larger sample should also help increase the reliability of results. However, as most Korean nuclear medicine workers are currently not necessary to monitored routinely for internal contamination with radionuclides. Notwithstanding, a continuous effort is recommended to reduce any unnecessary exposure to radioactive substances, even if in inconsequential amounts, by regularly surveying workplace environments and frequently monitoring atmospheric concentrations of radionuclides.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.435-444
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• 2001

Daily time series of longshore wind at 8 stations, sea surface temperature (SST) at 11 stations in the eastern coast of the Korean peninsula during $1983\~1997$ and the NOAA/AVHRR satellite data during $1990\~1998$ were used in order to study the temporal and spatial variations of the upwelling cold water which occurred in the summer season. The cold water occurred frequently in the eastern coastal waters of Korea such as Soimal, Kijang, Ulgi, Kampo, Pohang, Youngduk, Chukbyun, Chumunjin and Sokcho, During the upwelling cold water phenomenon, SST came down more than $-5^{\circ}C$ in a day. The maximum of the averaged RMS amplitude of daily SST was $5.8^{\circ}C$ along the eastern coast of Korea on Julian day 212 from $1983\~1997$. The cross correlation coefficients were higher than 0.5 between Sokcho and Chumunjin in the northern part of the East Sea, and along Soimal, Kijang, Ulgi, Kampo and Pohang in the southern part of the East Sea. In late July, 1995 the cold water occurred at Ulgi coastal area and extended to Ullung island which is located 250 km off the Ulgi coast. Even though the distance between Soimal and the Ulgi coast area is more than 120 km, the cross correlation coefficient related to the anomalies of SST due to upwelling cold water was the highest (0.7) in the southeastern coastal area of the Korean peninsula. This connection may be due to the cyclonic circulation of the Tsushima Current in this area and the topography of the ocean rather than the local south wind which induced the coastal upwelling.

• Tunnel and Underground Space
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• v.13 no.1
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• pp.52-63
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• 2003

Discontinuities such as faults, fractures and joints in rock mass play the dominant role in the mechanical and hydraulic properties of the rock mass. The key factors that influence on the flow of groundwater are hydraulic and geometric characteristics of discontinuities and their connectivity. In this study, a program that analyzes groundwater flow in the 3D discontinuity network was developed on the assumption that the discontinuity characteristics such as density, trace length, orientation and aperture have particular distribution functions. This program generates discontinuities in a three-dimensional space and analyzes their connectivity and groundwater flow. Due to the limited computing capacity In this study, REV was not exactly determined, but it was inferred to be greater than 25$\times$25$\times$25 ㎥. By calculating the extent of aperture that influences on the groundwater flow, it was found that the discontinuities with the aperture smaller than 30% of the mean aperture had little influence on the groundwater flow. In addition, there was little difference in the equivalent hydraulic conductivity for the the two cases when considering and not considering the boundary effect. It was because the groundwater flow was mostly influenced by the discontinuities with large aperture. Among the parameters considered in this study, the length, aperture, and orientation of discontinuities had the greatest influence on the equivalent hydraulic conductivity of rock mass in their order. In case of existence of a fault in rock mass, elements of the equivalent hydraulic conductivity tensor parallel to the fault fairly increased in their magnitude but those perpendicular to the fault were increased in a very small amount at the first stage and then converged.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.432-441
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• 2016

Machaerium cuspidatum, a canopy liana, is a species of genus legume in the Fabaceae family and contributes to the total species richness in the tropical rain forests. In the present study, we investigated the antioxidative and anti-cancer effects of M. cuspidatum and its mode of action. The methanol extract of M. cuspidatum (MEMC) exhibited anti-oxidative activity with an $IC_{50}$ value of $1.66{\mu}g/ml$, and this was attributable to its 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity. MEMC also exhibited a cytotoxic effect and induced morphological changes in a dose-dependent manner in several cancer cell lines including human lung adenocarcinoma A549 cells, human hepatocellular carcinoma HepG2 cells, and human colon carcinoma HT29 cells. Moreover, MEMC treatment induced the accumulation of subG1 population, which is indicative of apoptosis in A549 and HepG2 cells. MEMC-induced apoptosis was confirmed by the increase in Annexin V-positive apoptotic cells and apoptotic bodies using Annexin-V staining and DAPI staining, respectively. Further investigation showed that MEMC-induced apoptosis was associated with the increase in p53 and Bax expression, and the decrease in Bcl-2 expression. In addition, MEMC treatment led to proteolytic activation of caspase-3, 8, and 9 and degradation of poly-ADP ribose polymerase (PARP). Taken together, these results suggest that MEMC may exert a beneficial anti-cancer effect by inducing apoptosis via both the extrinsic and intrinsic pathways in A549 and HepG2 cells.

• Korean Journal of Psychosomatic Medicine
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• v.7 no.1
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• pp.103-115
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• 1999

Objectives : A large of studies have found an association between premenstrual syndrome and affective disorder, in particular, depression. Some studies have reported that women with depressive disorders may experience menstrual cycle-associated changes in the severity of their symptoms. This study was designed to compare the characteristics of premenstrual changes between control group and affective patient group, and to assess possible risk factors for premenstrual changes in patients. Methods : Eighty normal controls and eighty outpatients given maintenance therapy with fixed dose for at least more than four weeks were asked to complete questionnaires on menstrual history, obstetric-gynecological history, and functional impairment. In addition, to compare the characteristics of premenstrual changes, 16 items based on DSM-IV criteria A for premenstrual dysphoric disorder were rated on the following scale : 0(no change), 1(mild), 2(moderate), 3(severe). Moderate or severe change in each item was considered as premenstrual change and the subjects who reported more than one premenstrual change were defined as premenstrual change group. Results : The results were as follows : 1) The percentage of premenstrual change group was 32.6% in patient group and 50% in control group. 2) Frequently reported premenstrual changes were as follows in control group : breast tenderness; anger ; affective liability ; lethargy, easy fatigability, or marked lack of energy ; abdominal pain or discomfort. In patients, the mood or behavioral changes were frequently reported. The changes were as follows : lethargy, easy fatigability, or marked lack of energy ; change in appetite; affective liability ; sense of difficulty in concentrating : hypersomnia or insomnia. 3) In the premenstrual change group, the patients with only mood or behavioral changes were significantly more than those with only physical changes or both changes. 4) The severity of functional impairment was significantly correlated with the frequency of mood or behavioral changes in patients. 5) There were no significant differences in menstrual characteristics between patients with premenstrual changes and patients without them except the severity of dysmenorrhea. And the severity of dysmenorrhea was correlated with the frequency of premenstrual change. Conclusion : The proportion of patients with affective disorder, who reported moderate-to-severe premenstrual changes, experiencing mood or behavioral changes larger than those experiencing physical changes during premenstrual period. It is possible that some patients with affective disorder, who reported premenstrual mood or behavioral changes, suffer from coexisting premenstrual syndrome with affective disorder or premenstrual exacerbation of affective disorder. Since the more premenstrual changes, the severer functional impairment, the patients reporting mood or behavioral disturbance in premenstrual period should be carefully evaluated, and appropriate therapeutic stategies might be considered.

• The Korean Journal of Pesticide Science
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• v.11 no.4
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• pp.246-253
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• 2007

The reproduction toxicity of several pesticides on two Korean water flea was investigated to develop a new standard species used for ecological risk assessment of pesticide. Moina macrocopa and Daphnia sp. were exposed to 4 different types of pesticides over 10 and 21 days, respectively. No-ohserved effect concentration (NOEC) for synthetic pyrethroid, fenpropathrin on Moina macrocopa and Daphnia sp. were 0.17 and $0.06\;{\mu}g\;L^{-1}$, respectively. Diazinon, carbofuran and myclobutanil were in the order of their reproduction toxicity to cladocerans tested. There were large differences between Moina macrocopa and Daphnia sp. in their susceptibility to fenpropathrin, diazinon and carbofuran except myclobutanil. Daphnia sp. is more sensitive than M. macrocopa to pesticides tested. Therefore Daphnia sp. may be a good surrogate species to assess the reproduction effect of pesticides on aquatic invertebrates. M. macrocopa also be a good surrogate species because it is one of the most abundant cladocera in agricultural environment, especially rice paddy in Korea. In addition to it's ecological importance of wide spread distribution, it has also economical importance to make possible to shorten period for reproduction test using M. macrocopa due to it's short life cycle.