• Journal of the Mineralogical Society of Korea
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• v.15 no.4
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• pp.273-282
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• 2002

Al-pillared montmorillonite was synthesized from Na-saturated montmorillonite which was prepared by ionic substitution from Ca-montmorillonite of the Jabut mine, Gyeongiu City d(001), surface areas, and dehydration and ionic substitution properties have been compared for both Ca-montmorillonite and Al-pillared montmorillonite. d(001) spacings of Ca-montmorillonite and Al-pillared montmorillonite were 15.1 $\AA$ and $18.3\AA$, respectively. Dehydration took place before $350 ^{\circ}C$ in Ca-montmorillonite, whereas linealy up to $550^{\circ}C$ in Al-pillared montmorillonite. BET surface areas are 5～6 times larger in Al-pillared montmorillonite ($192 \m^2$/g) than Camontmorillonite. Ca-montmorilonite shows high selectivity for $Na^{＋}$ /, whereas Al-pillared montmorillonite for $Ca^{2＋}$ . The former shows decreasing d(001) spacing with increasing substitution of $Na^{＋}$ and irregular interstratified structure at high substitution of $Ca^{2＋}$ /, whereas the latter shows linear decreasing pattern in d(001) spacing with increasing $Ca^{ 2+}$.

• Journal of the Mineralogical Society of Korea
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• v.5 no.2
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• pp.93-101
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• 1992

Several "Napseok" mines are distribute in the Miryang area where the volcanic rocks are hydrothermally altered. The "Napseok" are pyrophyllite and dickite, with a small amount of silicates such as quartz, illite, tosudite and dumortierite. Other associated minerals are oxides, hydroxides, sulfides, sulfates and phosphates. Pyrophyllite which occurs as 2M polytype exhibits that the basal spacing increases due to dehydroxylation at 750${\circ}C$. Halloysite shows tubular forms. Wavellite is precipitated in fissures during the latest stage of the hydrothermal alteration process. Five mineral zones, that is pyrophyllite-deckite, illite, halloysite, silica, and albite-chlorite zones, are recognized with decreasing alteration degree. Clay minerals were formed by leaching of Si and alkali ions fron the country rocks, considering mineral assemblages, pyrophyllite polytype and thermodynamical data reported in the literature, temperatures of formation of main clay deposits are assumed to be 270 to 350${\circ}C$.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.4
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• pp.233-237
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• 2003

This study was conducted to provide a rational forest management method for a natural oak (Quercus variavilis) forest stand in the central part of South Korea based on characteristics of growth and water relation parameters. Average volume per hectare was 175.1 ㎥ in the study site of oak stands. Basal area and volume of each direction appeared to increase as the slope direction moves from north to south, but annual mean increment and periodic annual increment of DBH for 10 years showed the lowest value at the southern aspect. Maximum water potentials measured between 12 and 14 o'clock were analyzed by direction and elevation in the oak stands. Water potential of oak decreased as the slope changed from the north to the south aspect and water potential increased at lower elevations. Soil water content for the oak stands tended to decrease as the aspect shifted from north to south. Water potential and soil moisture content were highly correlated. It appears that oaks have a higher moisture requirement at the southern aspect, because of stand density related to intraspecific competition.

• Nutrition Research and Practice
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• v.7 no.3
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• pp.166-171
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• 2013

The purpose of this study was to investigate the effects of lotus leaf on hyperglycemia and dyslipidemia in animal model of diabetes. Inhibitory activity of ethanol extract of lotus leaf against yeast ${\alpha}$-glucosidase was measured in vitro. The effect of lotus leaf on the postprandial increase in blood glucose levels was assessed in streptozotocin-induced diabetic rats. A starch solution (1 g/kg) with and without lotus leaf extract (500 mg/kg) was administered to the rats after an overnight fast, and postprandial plasma glucose levels were monitored. Four-week-old db/db mice were fed a basal diet or a diet containing 1% lotus leaf extract for 7 weeks after 1 week of acclimation to study the chronic effect of lotus leaf. After sacrifice, plasma glucose, insulin, triglycerides (TG), total cholesterol (CHOL), high-density lipoprotein (HDL)-CHOL, and blood glycated hemoglobin levels were measured. Lotus leaf extract inhibited ${\alpha}$-glucosidase activity by 37.9%, which was 1.3 times stronger than inhibition by acarbose at a concentration of 0.5 mg/mL in vitro. Oral administration of lotus leaf extract significantly decreased the area under the glucose response curve by 35.1% compared with that in the control group (P < 0.01). Chronic feeding of lotus leaf extract significantly lowered plasma glucose and blood glycated hemoglobin compared with those in the control group. Lotus leaf extract significantly reduced plasma TG and total CHOL and elevated HDL-CHOL levels compared with those in the control group. Therefore, we conclude that lotus leaf is effective for controlling hyperglycemia and dyslipidemia in an animal model of diabetes mellitus.

• Korean Journal of Human Ecology
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• v.23 no.1
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• pp.137-148
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• 2014

The aim of this study was to determine whether the addition of soy isoflavones to dairy ice cream modifies diabetic biomarkers in the type 2 diabetic model mice. Forty male C57BL/6J-ob/ob mice were randomly divided into 4 groups and fed control diet (basal, 7% fat), MS diet (milk ice cream with sugar, 20% fat), MS-SI diet (MS ice cream with 0.01% soy isoflavones, 20% fat), or MF-SI diet (milk ice cream with 0.01% soy isoflavones, 5% fructooligosaccharide, 20% fat) for 12 weeks. Blood response area by glucose tolerance test, plasma levels of glucose, insulin, C-peptide, leptin, and blood $HbA_{1c}$ were not significantly different among all the groups. Concentrations of interleukin-6 and tumor necrosis factor-${\alpha}$ secreted from splenocytes induced by Concanavalin A were not significantly different among all the groups. In conclusion, soy isoflavones supplemented to ice cream did not alter diabetic biomarkers in diabetic type 2 model mice.

• Archives of Plastic Surgery
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• v.33 no.5
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• pp.541-545
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• 2006

Purpose: There are many methods for the reconstruction of the facial defect after an excision of a skin cancer; such as skin graft, local flap, free flap, etc... Skin graft has its' limitations; it could remain in different color with in regards of the recipient to donor, with an unfavorable scar. Free flap can lead to big donor site morbidity with long operation time and uncontrolled scar as a disadvantage factor. Compared to the prior, local flap offers several merits; sufficient blood supply, good tissue quality and short operation time. We revised 'V-Y-S flap' for the facial defect, which proved to have favorable outcomes. Methods: Total 7 V-Y-S flaps were performed to patients with skin cancers(six squamous cell carcinoma and one basal cell carcinoma). Two of these flaps were combined with composite grafts, one with full thickness skin graft. Six patients were female and one male. The average diameter of defects after excision was 2.3 cm. The follow-up period was 18 months maximally. Results: We treated seven facial skin cancers with 'V-Y-S flap'. There were no flap necrosis, cancer recurrence and scar contracture as a result. Furthermore, this method also offers a favorable central scar line that is parallel to the nasolabial fold and the nasojugal groove, especially in the nasolabial area and superomedial side of the cheek. With this method, we could cover a maximum diameter of 4cm facial defect. Conclusion: In conclusion, it is suggested that V-Y-S flap is a useful method to cover facial defects after the excision of a skin cancer.

• Ocean and Polar Research
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• v.24 no.4
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• pp.483-490
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• 2002

Detailed investigations on both submarine and subaerial volcaniclastic deposits around Dokdo were carried out to identify geomorphologic characteristics, stratigraphy, and associated depositional processes of Dokdo caldera. Dokdo volcano has a gently sloping summit (about 11km in diameter) and relatively steep slope (basal diameter is about 20-25 km) rising above sea level at about 2,270m. We found ragged, elliptical-form of Dokdo caldera with a diameter of about 2km estimated by Chirp (3-11 kHz) sub-bottom profile data and side scan sonar data for the central summit area of Dokdo volcano. We interpreted that the volcaniclastic deposits of Dokdo unconformably consist of the Seodo (west islet) and the Dongdo(east islet) formations based on internal structure, constituent mineral composition, and bedding morphology. The Seodo Formation mainly consisted of massive or inversely graded trachytic breccias (Unit S-I), overlain by fine-grained tuff (Unit S-II), which is probably supplied by mass-wasting processes resulting from Dokdo caldera collapse. The Dongdo Formation consists of alternated units of stratified lapilli tuff and inversely graded basaltic breccia (Unit D-I, Unit D-III, and Unit D-V), and massive to undulatory-bedded basaltic tuff breccias (Unit D-II and Unit D-IV) formed by a repetitive pyroclastic surge and reworking processes. Although, two islets of Dokdo are geographically near each other, they have different formations reflecting their different depositional processes and eruptive stages.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.5
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• pp.305-312
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• 2012

This study was to determine the effect of exercise on the recovery of dopaminergic neuron loss and muscle atrophy in 6-OHDA-induced hemi Parkinson's disease model. Exercise was loaded twice per day for 30 minutes each time, at 5 days after 6-OHDA lesioning and continued for 16 days using a treadmill. Exercise significantly increased the number of tyrosine hydroxylase positive neuron in the lesioned substantia nigra and the expression level of tyrosine hydroxylase in the striatum compared with the control group. To examine which signaling pathways may be involved in the exercise, the phosphorylation of $GSK3{\beta}$ and ERK were observed in the striatum. In the control group, basal level of $GSK3{\beta}$ phosphorylation was less than in both striatum, but exercise increased it. ERK phosphorylation decreased in the lesioned striatum, but exercise recovered it. These findings suggest that exercise inactivates $GSK3{\beta}$ by phosphorylation which may be involved in the neuroprotective effect of exercise on the 6-OHDA-induced cell death. In the exercise group, weight, and Type I and II fiber cross-sectional area of the contralateral soleus significantly recovered and expression of myosin heavy chain and Akt and ERK phosphorylation significantly increased by exercise. These results suggest that exercise recovers Parkinson's disease induced dopaminergic neuron loss and contralateral soleus muscle atrophy.

• Journal of Forest and Environmental Science
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• v.33 no.3
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• pp.172-186
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• 2017

The effects of application of fuel-reduction treatment in wildfire management has not been tested in dry forests of Ghana. Therefore, the short-term ecological effects of prescribed burning and hand thinning treatments followed by experimental wildfire were investigated in degraded forests and Tectona grandis forest plantations in two forest reserves of different levels of dryness in Ghana. The results showed that more trees were killed in prescribed burning (average of 41% in degraded forest and 18% in plantations) than hand thinning (7.2% in degraded forests and 8% in plantation). More tree seedlings were also killed in prescribed burning (72%) than hand thinning (47%). The mortality of trees and seedlings were greater in Worobong South forest, a less dry forest reserve than the Afram Headwaters forest, a drier forest reserve. Fuel treatment especially prescribed burning compared to the control reduced wildfire effects on forest canopy particularly in the less dry forest and tree mortality especially in the drier forest. Prescribed burning temporarily increased pH, exchangeable potassium (52%) and available phosphorus (82%) in the surface soils of the entire plots. The two fuel treatment methods did not have much influence on basal area, organic matter and total nitrogen. Nevertheless, they were able to reduce the adverse wildfire effects on soil pH, exchangeable potassium, available phosphorus, organic matter and total nitrogen concentrations. Fuel treatments therefore have potential application in dry forest management in Ghana due to their ability to retain important forest ecological traits after a wildfire incidence.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.189-194
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• 1989

This study was carried out on 10 persons of female farmers to determine the energy expenditure of agricultural work. Their mean age was 44 year-old, mean daily urinary nitrogen excretion was 11.3g, and creatinine excretion was 0.183g. The energy metabolism was determined by indirect calorimetry using Douglas bag and Scholander's gas analyzer. The measured basal metabolism was 1,273 kcal per day and rest metabolism was 1,614 kcal per day. To remove seedling from the seedplot, they spent 2.479kcal per minute, to weed 2.805kcal/min, and to reap with sickle 4.58kcal/min. Energy expenditure of the same work, only sitting on the stool, was significantly reduced. Prolonged work did not change energy expenditure per minute significantly.