• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.261-281
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• 2016

Our knowledge of the lithosphere beneath the Korean Peninsula has been improved through petrologic and geochemical studies of upper mantle xenoliths hosted by Quaternary intraplate alkali basalts from Jeju Island. The xenoliths are mostly spinel lherzolites, accompanied by subordinate harzburgite and pyroxenites. The mantle xenoliths represent residual mantle material showing textural and geochemical evidence for at least a three-stage evolution, fractional partial melting, recrystallization, and metasomatism. Their composition primarily controlled by early fractional melt extraction and porphyroclastic and mylonitic fabrics formed in a shear-dominated environment, which was subsequently modified by residual slab-derived fluids (or melts). Modal metasomatic products occur as both anhydrous phase(orthopyroxene) and hydrous phase (phlogopite). Late-stage orthopyroxene is more common than phlogopite. However, chemical equilibrium is evident between the primary and secondary orthopyroxene, implying that the duration of post-metasomatic high temperatures enabled complete resetting/reequilibration of the mineral compositions. The metasomatic enrichment pre-dates the host Jeju Quaternary magmatism, and a genetic relationship with the host magmas is considered unlikely. Following enrichment in the peridotite protolith in the mantle wedge, the upper mantle beneath proto-Jeju Island was transformed from a subarc environment to an intraplate environment. The Jeju peridotites, representing old subarc fragments, were subsequently transported to the surface, incorporated into ascending Quaternary intraplate alkali basalt. The result of this study implies that long term material transfer in the transformation of geotectonic setting from a subarc to intraplate may have played a significant role in the evolution of lithospheric mantle, resulting in the enriched mantle domains, such as EM I or EM II in the lithospheric mantle beneath East Asia.

• Economic and Environmental Geology
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• v.45 no.4
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• pp.385-396
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• 2012

The geochemical high-grade uranium anormal zone has been reported in the Shinbo mine and its eastern areas, Jinan-gun, Jeollabuk-do located in the southwestern part of Ogcheon metamorphic zone, Korea. In this paper is reported the time-relationship between deformation and growth of metamorphic minerals in the eastern area of Shinbo mine, which consists of the Precambrian metasedimentary rocks (quartzite, metapelite, metapsammite) and the age-unknown pegmatite and Cretaceous porphyry which intrude them, and is considered the relative mineralization time on the basis of the previous research's result. The D1 deformation formed the straight-type Si internal foliation which is defined mainly as the arrangement of elongate quartz, biotite, opaque mineral in andalusite porphyroblast. The D2 deformation, which is defined by the microfolding of Si foliation, formed S2 crenulation cleavage. It can be divided into two sub-phases, early crenulation and late crenulation. The former occurs as the curvetype Si foliation in the mantle part of andalusite. The latter occurs as S1-2 composite foliation which warps around the andalusite. The andalusite porphyroblast began to grow under non-deformation condition after the formation of S1 foliation which corresponds to the straight-type Si foliation. It continued to grow before the late crenulation phase. The age-unknown pegmatite intruded after the D2 deformation and grew the fibrous sillimanite which random masks the S1-2 composite foliation. The D3 deformation formed F3 fold which folded the S1-2 composite foliation, D2 crenulation, fibrous sillimanite. It means that the intrusion of pegmatite related to the growth of the fibrous sillimanite took place during the inter-tectonic phase of D2 and D3 deformations. The retrograde metamorphism is recognized by the chloritization of biotite and two-way cleavage lamellae which is parallel to the S1-2 composite foliation and the F3 fold axial surface in the andalusite porphyroblast. It occurred during the D2 late crenulation phase and D3 deformation. In considering of the previous research's result inferring the most likely candidate for the uranium source rock as pegamatite, it indicates that the age-unknown pegmatite intruded during the inter-tectonic phase of D2 and D3 deformations, i.e. during the retrograde metamorphism related to the uplifting of crust, and formed the uranium ore zone around the Shinbo mine.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.931-944
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• 2016

This study was conducted to compare among bull, steer and heifer on growth performance, blood composition and carcass traits according to fattening phase in Hanwoo. 12 month of aged 4 bulls ($339.8{\pm}18.5kg$), 4 steers ($309.8{\pm}13.2kg$), and 3 heifers ($290.0{\pm}16.7kg$) were allocated in the stalls with individual feeding system during 20 months. Average daily gain was not different among the treatment groups during early fattening phase, but higher in the bulls and lower in the heifers after mid-fattening phase (p<0.05). The difference of body size by animal groups appeared from 24 month of age, and wither height and body length of Hanwoo heifer were the smallest (p<0.05) among treatment group. But wither height was not difference among treatment groups at 32 month of age. At 12 month of age, concentrations of serum cholesterol, triglyceride, glucose and total protein were higher in the heifers compared to other groups, and serum GPT (Glutamic pyruvic transaminase) was the highest (p<0.05) in the bulls, and serum GOT (Glutamic oxaloacetic transaminase) was the highest (p<0.05) at late fattening phase in the bulls. Meat yield index was similar between the bulls and the heifers, and the lowest (p<0.05) in the steers. Marbling score was significantly higher (p<0.05) in the steers and the heifers than in the bulls, and meat quality was the best in the steers among treatment groups. The results of this experiment might be used as a basal data on difference between gender in revision of Korean feeding standard for Hanwoo.

• The Journal of the Petrological Society of Korea
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• v.25 no.4
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• pp.389-400
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• 2016

The study area, which is located in the southeastern part of the Jirisan province of the Yeongnam massif, Korea, consists mainly of the Precambrian Sancheong anorthosite complex and the Jirisan metamorphic rock complex, the Mesozoic granitoids which intruded them. Several fracture sets with various geometric indicators, which determine their relative timing and shear sense, are well observed in the Sancheong anorthosite complex. The aim of this study is to determine the development sequence of extension fractures, the movement sense and development sequence of shear fractures in the Sancheong anorthosite complex on the basis of detailed analysis of their geometric indicators. This study suggests fracture system of the Sancheong anorthosite complex was formed at least through five different fracturing events, named as Dn to Post-Dn+3 phases. (1) Dn phase: extension fracturing event of NNW trend. The fracture set experienced the reactivations of dextral ${\rightarrow}$ sinistral shearing with the change of stress field afterward. (2) Dn+1 phase: extension fracturing event of (N)NE trend. The fracture set experienced the reactivations of sinistral ${\rightarrow}$ sinistral ${\rightarrow}$ dextral. (3) Dn+2 phase: extension fracturing event of NW trend. The fracture set experienced the activated of dextral shearing. (4) Dn+3 phase: extension fracturing event of N-S trend. (5) Post-Dn+3 phase: extension fracturing event of (E)NE trend. Dn deformation formed during the early Songnim orogeny. Dn+1 deformation formed during the late Songnim orogeny. Dn+2 deformation formed during the Daebo orogeny. Dn+3 deformation formed during the Bulguksa orogeny.

• International Journal of Oral Biology
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• v.33 no.1
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• pp.33-43
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• 2008

In the process of bone remodeling, mineral phase of bone is dissolved by osteoclasts, resulting in elevation of calcium concentration in micro-environment. This study was performed to explore the effect of high extracellular calcium ($Ca{^{2+}}_e$) on mineralized nodule formation and on the expression of progressive ankylosis (Ank), plasma cell membrane glycoprotein-1 (PC-1) and osteopontin by primary cultured mouse calvarial cells. Osteoblastic differentiation and mineralized nodule formation was induced by culture of mouse calvarial cells in osteoblast differentiation medium containing ascorbic acid and ${\beta}$-glycerophosphate. Although Ank, PC-1 and osteopontin are well known inhibitors of mineralization, expression of these genes were induced at the later stage of osteoblast differentiation during when expression of osteocalcin, a late marker gene of osteoblast differentiation, was induced and mineralization was actively progressing. High $Ca{^{2+}}_e$(10 mM) treatment highly enhanced mRNA expression of Ank, PC-1 and osteopontin in the late stage of osteoblast differentiation but not in the early stage. Inhibition of p44/42 MAPK activation but not that of protein kinase C suppressed high $Ca{^{2+}}_{e^-}$induced expression of Ank, PC-1 and osteopontin. When high $Ca{^{2+}}_e$(5 mM or 10 mM) was present in culture medium during when mineral deposition was actively progressing, matrix calcifiation was significantly increased by high $Ca{^{2+}}_e$. This stimulatory effect was abolished by pyrophosphate (5 mM) or levamisole (0.1-0.5 mM), an alkaline phosphatase inhibitor. In addition, probenecid (2mM), an inhibitor of Ank, suppressed matrix calcification in both control and high $Ca{^{2+}}_{e^-}$treated group, suggesting the possible role of Ank in matrix calcification by osteoblasts. Taken together, these results showed that high $Ca{^{2+}}_e$ stimulates expression of Ank, PC-1 and osteopontin as well as matrix calcification in late differentiation stage of osteoblasts and that p44/42 MAPK activation is involved in high $Ca{^{2+}}_{e^-}$induced expression of Ank, PC-1 and osteopontin.

• Radiation Oncology Journal
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• v.20 no.1
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• pp.53-61
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• 2002

Purpose : To determine the optimal scheme of postoperative chemoradiotherapy in rectal cancer by comparing survival, Patterns of failure, toxicities in early and late radiotherapy groups using a Phase III randomized prospective clinical trial. Materials and Methods : From January 1996 to March 1999, 307 patients with curatively resected AJCC stage II and III rectal cancer were assigned randomly to an 'early (151 patients, arm 1)' or a 'late (156 patients, arm II)' and were administered combined chemotherapy (5-FU $375\;mg/m^2/day$, leucovorin $20\;mg/m^2$, IV bolus daily, for 3 days with RT, 5 days without RT, 8 cycles with 4 weeks interval) and radiation therapy (whole pelvis with 45 Gy/25 fractions/5 weeks). Patients of arm I received radiation therapy from day 1 of the first cycle of chemotherapy and those of arm II from day 57 with a third cycle of chemotherapy. The median follow-up period of living patients was 40 months. Results : Of the 307 patients enrolled, fifty patients did not receive scheduled radiation therapy or chemotherapy. The overall survival rate and disease free survival rate at 5 years were $78.3\%\;and\;68.7\%$ in arm I, and $78.4\%\;and\;67.5\%$ in arm II. The local recurrence rate was $6.6\%\;and\;6.4\%$ (p=0.46) in arms I and II, respectively, no significant difference was observed between the distant metastasis rates of the two arms ($23.8\%\;and\;29.5\%$, p=0.16). During radiation therapy, grade 3 diarrhea or more, by the NCI common toxicity criteria, was observed in $63.0\%\;and\;58.2\%$ of the respective arms (p=N.S.), but most were controlled with supportive care. Hematologic toxicity (leukopenia) greater than RTOG grade 2 was found in only $1.3\%\;and\;2.6\%$ of patients in each respective arm. Conclusion : There was no significant difference in survival, patterns of failure or toxicities between the early and late radiation therapy arms. Postoperative adjuvant chemoradiation was found to be a relatively safe treatment but higher compliance is needed.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.1
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• pp.25-33
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• 1998

Cyclooxygenase (COX) is an enzyme involved in the conversion of arachidonic acid to prostaglandins (PGs), and exists in two forms, COX-1 and COX-2. COX has been reported to be involved in early implantation by secretion of PGs which causes permeability of vessels and reaction of decidual cells around the implantation site. Recently, in mice and sheep studies, COX-1 and COX-2 expression in the endometrium has been reported to be different according to implantation and stages of the estrous cycle, but expression of COX-1 and COX-2 in human endometrium during the menstrual cycle has not yet been established. The purpose of this study was to observe the variances of COX-1 and COX-2 expression by immunohistochemical staining in endometrial samples obtained from human hysterectomy specimens and biopsies of women of reproductive age according to different stages of the menstrual cycle. Also, we attempted to observe COX-1 and COX-2 expression in the epithelial and stromal cells of the endometrium obtained during the mid-secretory phase, which were cultured separately. COX-2 showed a cyclic pattern of expression according to the different stages of the menstrual cycle and was strongly expressed particularly at the mid-secretory phase which corresponds to the time of implantation. However, COX-1 tended to be increased in the early proliferative, and mid- and late secretory phases, but was also expressed in the whole menstrual cycle showing no particular pattern. In the separately cultured cells COX-1 was expressed in epithilial cells and COX-2 in the stromal cells. The above results suggest that since COX-2 is expressed at the same time as implantation and cultured cells display a specific secretory pattern, COX-2 has inductive endocrine enzyme properties and has an important effect on endometrial cells during implantation. Also, COX-2 expression in endometrial cells may be utilized as a useful marker of endometrial maturation.

• Journal of Biomedical Engineering Research
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• v.43 no.5
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• pp.331-340
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• 2022

Early afterdepolarization (EAD), a significant cause of fatal ventricular arrhythmias including Torsade de Pointes (TdP) in long QT syndromes, is a depolarizing afterpotential at the plateau or repolarization phase in action potential (AP) profile early before completing one pace. AP duration prolongation is related to EAD but is not necessarily accounted for EAD. Several computational studies suggested EAD can form from an abnormality in the late plateau and/or repolarization phase of AP shape. In this sense, we hypothesized the slope during repolarization has the characteristics to predict TdP risk, mainly focusing on the maximum slope during repolarization (dVm/dt_{max_repol}). This study aimed to predict the sensitivity of dVm/dt_{max_repol} to ion channel conductances as a TdP risk metric through a population simulation considering multiple effects of simultaneous reduction in six ion channel conductances of g_NaL, g_Kr, g_Ks, g_to, g_K1, and g_CaL. Additionally, we verified the availability of dVm/dt_{max_repol} for TdP risk prediction through the correlation analysis with qNet, the representative TdP metric. We performed the population simulations based on the methodology of Gemmel et al. using the human ventricular myocyte model of Dutta et al. Among the sixion channel conductances, dVm/dt_{max_repol} and qNet responded most sensitively to the change in g_Kr, followed by g_NaL. Furthermore, dVm/dt_{max_repol} showed a statistically significant high negative correlation with qNet. The dVm/dt_{max_repol} values were significantly different according to three TdP risk levels of high, intermediate, and low by qNet (p<0.001). In conclusion, we suggested dVm/dt_{max_repol} as a new biomarker metric for TdP risk assessment.

• Journal of Chest Surgery
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• v.40 no.7 s.276
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• pp.485-491
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• 2007

Background: Thoracoplasty has become a rarity in current clinical practice, although it has been widely employed for well over a century as a procedure for reducing the capacity of the thoracic cavity. Yet we have perform tailoring thoracoplasty following or concomitant with pulmonary resection in 20 patients. The aim of this study is to evaluate the early and late clinical results and also the significance of tailoring thoracoplasty. Material and Method: From March 1995 to June 2005, modified thoracoplasty following or concomitant with pulmonary resection was performed in 20 patients out of a total of 298 pulmonary resections for closing air leaks and for treating persistent pleural space following pulmonary resections, and to tailor the thoracic cavity to accept a diminished lung volume. Of the 20 patients, 14 patients had tailoring thoracoplasty performed concomitant with pulmonary resection, and the remaining 6 patients also had tailoring thoracoplasty performed following pulmonary resection. The subjects ages ranged from 24 to 77 (mean $59.1{\pm}6.4$) and a male preponderance was noted (17 : 3); the number of left and right surgeries was equal. The preoperative primary underlying diseases were lung cancer in 7 patients, pneumothorax with giant bullous change in 6 patients, bronchiectasis in 2 patients, previous pulmonary tuberculosis associated with aspergilloma in 2 patients, empyema with fibrothorax in 2 patients and multiple lung abscesses & destruction due to previous trauma in 1 patient. The operative methods were apicolysis and subperiosteal removal of the 2nd, 3rd and 4th ribs (the costochondral junction to the posterior portions of the ribs) with preservation of the first rib and compression of the anterior chest via cotton bags and elastic bandages. Result: The mean duration of the air leaks after thoracoplasty was $1.6{\pm}0.2$ days (range: $0{\sim}7$ days) and the mean duration of an indwelling chest tube was 7 days (range: $5{\sim}11$ days); the mean duration of hospitalization was $19.2{\pm}2.8$ days (range: $8{\sim}47$ days). The postoperative complications were wound infection (2) and pneumonia (2); reoperation was done due to bleeding (1) in one patient who underwent concomitant thoracoplasty and there was 1 case of wound infection (1) after postresection thoracoplasty. The mortality was 1 patient in the early phase and 4 patients in the late phase. Conclusion: We conclude that tailoring thoracoplasty may be performed to close anticipated persistent pleural spaces and to accommodate the diminished lung volume with acceptable cosmetic results when this procedure is combined with pulmonary resection in selected patients.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.6-10
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• 2003

The present study investigated peripheral plasma immunoreactive inhibin (ir-inhibin) concentrations in relation to the stage of oestrous cycle and progesterone concentrations in cycling Sahiwal cattle (Bos indicus) and Murrah buffaloes (Bubalus bubalis). Blood samples were collected once daily for thirty-two consecutive days from cattle and buffaloes (5 each) during winter months of January and February. Mean (${\pm}$S.E.M.) plasma ir-inhibin concentrations ranged from $0.40{\pm}0.01$ to $0.59{\pm}0.03ng/ml$ in cattle and from $0.29{\pm}0.03$ to $0.52{\pm}0.05ng/ml$ in buffaloes. In cattle, ir-inhibin concentrations increased from $0.47{\pm}0.07ng/ml$ on day -4 (day 0=day of oestrus) to reach a maximum value of $0.59{\pm}0.03ng/ml$ on day -2. Thereafter, ir-inhibin concentrations showed a decline to reach a low of $0.40{\pm}0.01ng/ml$ on day 11 of the oestrous cycle. In buffaloes, ir-inhibin concentrations increased from $0.38{\pm}0.04 ng/ml$ on day -4 to reach a maximum concentration of $0.52{\pm}0.05ng/ml$ on day -2. Ir-inhibin concentrations then declined to reach a low of $0.29{\pm}0.03ng/ml on day 9 of the cycle. In both cattle and buffaloes, ir-inhibin concentrations which were lowest ($0.43{\pm}0.02$ and $0.34{\pm}0.02ng/ml$, respectively) during the mid-luteal phase of the oestrous cycle increased (p<0.05) to $0.52{\pm}0.03$ and $0.44{\pm}0.04ng/ml$, respectively, during the late luteal phase, and then further to the highest value of $0.53{\pm}0.02$ and $0.49{\pm}0.04ng/ml$, respectively, during the perioestrus phase, following which these declined to $0.50{\pm}0.02$ and $0.39{\pm}0.03ng/ml$, respectively, during the early luteal phase. The variations in peripheral plasma ir-inhibin profile in both the species appear to be related to the changes in characteristics of follicular populations during the oestrous cycle. Peripheral plasma ir-inhibin concentrations were negatively correlated with progesterone concentrations in cattle (r=-0.51, p<0.01) and buffaloes (r=-0.30, p<0.01) indicating that the corpus luteum is not a source of peripheral ir-inhibin in these species.