• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.325-330
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• 2000

Alginate obtained from brown algae had various physicochemical and rheological properties and could used as a dietary fiber, However, alginate has not been widely applied to the food industry, since it had high viscosity, high gelling effect conjugated with some mineral, and low solubility. To improve functionality of alginate, partially develymerized alginates, which was water-soluble dietary fiber were obtained by hydrolysis of alginate from the sea tangle, Laminaria japonicus, heated at $121^{\circ}C$. Effects of depolymerization of alginate on the changes of viscosity and average molecular weight, block composition ratio of mannuronate to guluronate (M/G ratio), chemical properties using $PT-IR, ^1H-NMR, and ^(13)C-NMR$ spectrum were investigated. The average molecular weight and viscosity of the alginate were rapidly decreased with the thermal decomposition, and estimated to be 1,307,415 dalton and 284,000 cps, before heating, 728,106 and 3,940.29 cps after 30 min heating, 102,635 and 22.22 cps after 2.5 hrs heating, 51,205 and 12.05 cps after 3 hrs, and 10,049 and 4.28 cps after 6.5 hrs, respectively. The M/G ratio was increased with the heating time, while MM-block did not show any changes and GG-block diminished. The results of $FT-IR, ^1H-NMR and ^(13)C-NMR$ spectrum suggested that changes of molecular structure did not occur by the thermal decomposition.

• Restorative Dentistry and Endodontics
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• v.17 no.2
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• pp.307-330
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• 1992

The aim of this study was to investigate the physical properties of visible light curing Glass Ionomer cement for restorative esthetic filling. The control group was the autopolymerizing GC Fuji II Glass Ionomer cement (2.2: 1 P/L ratio) and the experimental groups were made by following procedure. To induce the polymerization by visible light, the powder of GC Fuji II GI cement and the liquid of Vitrabond for base & liner were mixed in an amalgam capsule with 2.5:1, 3.0:1, 3.5:1 P/L ratio (% wt/wt). After fabrication of specimens, compressive strength, fracture toughness ($K_{IC}$) Scanning Electron Microscope and X-ray Diffraction, water-leachable content, marginal leakage and surface roughness were studied. The results were as follows: 1. Only experimental No. 1 group (visible light curing) showed less compressive strength than control group 1 hour after curing. Strength was increased with aging in all groups, so the compressive strength of light curing groups was no less than that of autopolymerizing group after 3 weeks. 2. Experimental No.3 group (visible light curing) was inferior to No.2 group (visible light curing) in fracture resistance but light curing groups were more resistant to fracture than autopolymerizing group and showed ductile fracture pattern as compared with the brittle fracture pattern of autopolymerizing group. 3. From scanning electron microscopic image, various sized unreacted powder particles, surrounded by silica gel, were embedded in polysalt matrix. Light curing groups showed little crack and more dense unreacted particles than autopolymerizing group. 4. From X-ray diffraction analysis, GC Fuji II Glass Ionomer cement powder and all groups showed glassy appearance but light curing groups seemed to be more intensive in crystaline than autopolymerizing group. S. The most significant dissolution was shown in early setting period in all group. Light curing groups were dissolved less than autopolymerizing group. 6. Marginal leakage was not different significantly in case of cavity margin composed of same tooth structure (ex. only enamel margin, only dentin margin) but much more leakage was shown in dentin/cementum margin than enamel margin. In only case of only enamel margin, light curing groups were superior to autopolymerizing group. 7. All groups showed relatively smooth surface, which irregularity was less than $1{\mu}m$. Light curing groups were smoother than autopolymerizing group.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.330-339
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• 2009

The material properties of Cedar (Cryptomeria japonica) were evaluated according to heat treatment conditions. The special focus was made on the color control of cedar wood by heat treatment. The difference of color between sapwood and heartwood could be reduced by heat treatment at a temperature above $170^{\circ}C$. Long heating time was more effective in reducing the difference. The Equilibrium Moisture Content (EMC) of heat-treated wood was as low as 50 percent. The result obviously indicates that heat-treated wood is more dimensionally stable in the change of moisture condition than the control. The heat-treated wood was also effective in increasing the durability against wood rotting fungi. However, more study is required to develop heat treatment as an environmentally-friendly technology for wood preservation without chemical. The mechanical properties of heat-treated wood showed relatively higher performance than the control in general. Meanwhile the dramatic decrease in impact bending stress due to the loss of ductility may limit uses of heat-treated wood in certain cases. There were no significant changes in microscopic structure which may cause changes in mechanical properties. Further study on the chemical analysis of heat-treated wood is needed to scrutinize the causes of changes of material properties.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.324-330
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• 1986

The responses of brain acetylcholinesterase(Ach-E) and plasma cholinesterase (Ch-E) activities were studied in chicknes given oral doses of Terbufos(S-tert-butyl thiomethyl 0,0-diethyl phosphorodithioate), an organophosphorus insecticide. The acute oral $LD_{50}$ of terbufos was 1.82mg/kg. The activity of plasma Ch-E was inhibited more rapidly than that of brain Ach-E, whereas recovery of plasma Ch-E activity was more rapid than that of brain Ach-E. Recovery of brain Ach-E and plasma Ch-E was followed the model $Y=a+b(log_{10}X)$. Brain Ach-E activity and plasma Ch-E were inhibited 83% and 94%, respectively, at 60min after administered oral $LD_{50}$. Brain Ach-E and plasma Ch-E was inhibited in vitro by Terbufos

• Journal of Applied Biological Chemistry
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• v.59 no.4
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• pp.323-330
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• 2016

Pinellia ternata Breitenbach, the natural medicinal plant of the Araceae family, is a perennial plant originated from the East Asia, but also widely distributed in Europe and North America. Its tuber is used as traditional medicine for treatment of various diseases such as vomiting, inflammation, and traumatic injury. Pharmacological studies revealed that P. ternata possesses anticonvulsant, anti-tumor, insecticidal, and cytotoxic activities. Despite being well-known as the useful medicinal plant, there is no reliable, standardized method for origin discrimination. Ultra performance liquid chromatography-photodiode array detector and quadrupole time of flight-mass spectrometry based metabolite-profiling was applied to explore significant metabolite for origin discrimination between Korean and Chinese P. ternata. One compound was isolated from Korean P. ternata using repeated ODS column chromatography by bioactivity guided fractionation, and determined as [6]-gingerol according to the results of spectroscopic data including nuclear magnetic resonance and MS. This compound was selected as cosmeceutical biomarker by fingerprints, and it was associated to melanin inhibitory effect determining its origin authenticity. Furthermore, the calibration curve of biomarker was prepared using validated method for the comparison of content between Korean and Chinese P. ternata. This is the report to address the selection and successful validation of the discriminant metabolite for confirmation of Korean P. ternata.

• Korean journal of applied entomology
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• v.40 no.4
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• pp.337-344
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• 2001

The house fly (Musca domestica L.) strains were derived from the Yumenoshima III strain by selecting with cypermethrin and methomyl for 19 and 16 generations, respectively. The resulting strains, cypermethrin resistance strain (Cyp-R19) and methomyl resistance strain (Met-R16), showed high level of resistance by 12906 and 51 times, respectively, comparing with the susceptible SRS strain. The Cyp-R19 strain was resistant to synthetic pyrethroids such as deltamethrin, esfenvalerate, fenpropathrin, $\beta$-cyfluthrin, showing > 11000, 1231, 103, 292 times higher $LD_{50}$ values than the SRS strain, respectively. It was also resistant to 3 organophosphates and 2 carbamates such as fenitrothion, profenofos, pyridaphenthion, benfuracarb, methomyl, showing resistance ratios fo 51, 17, 49, 39 and 62 comparing to SRS strain. The Met-R16 strain was resistant to synthetic carbamate benfuracarb, showing 6 times higher $LD_{50}$ value than SRS strain. It was also resistant to 4 organophosphates such as acephate, fenitrothion, profenofos and pyridaphenthion, showing > 40, 103, 19, 60 times higher $LD_{50}$ value. It was also resistant to 5 pyrethroids and a pyrrole such as cypermethrin, deltamethrin, esfenvalerate, fenpropathrin, $\beta$-cyfluthrin and chlorfenapyr, showing 3030, 249, 4063, 34, 330 and 86 times higher $LD_{50}$ values than the SRS strain. Cyp-R14 strain which was selected for 14 generations by cypermethrin and developed 11014 times higher resistance to the SRS strain was used in the dominance and linkage group analysis. Cypermethrin resistance inheritance was incompletely dominant in house fly as judged by the reciprocal cross between the resistant and susceptible strains. The linkage group analysis for the major factors responsible for this resistance was carried out by the$ F_1$male-backcross method, using susceptible multi-chromosomal marker aabys strain. The major factors for cypermethrin resistance were located on the 1st, the 3rd and the 4th chromosomes, and the effect of the 3rd chromosome was most prominent.

• Journal of the Korea Concrete Institute
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• v.23 no.3
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• pp.321-330
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• 2011

Recently, the effects of high temperature and fiber content on the residual mechnical properties of high-strength concrete were experimentally investigated. In this paper, residual mechanical properties of concrete with water to cement (w/c) ratios of 0.55, 0.42 and 0.35 exposed to high temperature are compared with those obtained in fiber reinforced concrete with similar characteristics ranging from 0.05% to 0.20% polypropylene (PP) fiber volume percentage. Also, factors including pre-load levels of 20% and 40% of the maximum load at room temperature are considered. Outbreak time, thermal strain, length change, and mass loss were tested to determine compressive strength, modulus of elasticity, and energy absorption capacity. From the results, in order to prevent the explosive spalling of 50 MPa grade concretes exposed to high temperature, more than 0.05 vol. % of PP fibers is needed. Also, the cross-sectional area of PP fiber can influence the residual mechanical properties and spalling tendency of fiber reinforced concrete exposed to high temperature. Especially, the external loading increases not only the residual mechanical properties of concrete but also the risk of spalling and brittle failure tendency.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.2
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• pp.330-342
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• 2016

The aim of this article is to explore some issues on the uneven regional development in the Republic of Korea. Along with this, case studies on the United Kingdom and Italy are conducted in terms of their wealth, inequality and regional development. In the period of 1995~2003, the UK experienced the intensified uneven regional development and continuous increase of its index due in the main to the delayed revitalization of industrial decline regions, neo-liberalistic local labour market and industrial policies, and institutional instability of regional policies. In the case of Italy, it seemed to experience relatively stable regional convergence. However, this was caused by the continuous decline of major metropolitan areas such as large cities, Milan, Turin, Genoa, to name but a few. The Republic of Korea experienced 'economic growth with spatial and social disparities.' Since 2003 the uneven regional development has intensified. Towards regional convergence, new engines of regional development, the investment in the specialization of small and medium cities, and supportive policies for industrial restructuring regions are required.

• Journal of Korean Academy of Nursing
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• v.17 no.3
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• pp.184-194
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• 1987

The purposes of this study were; 1) to gather data relevant to demographic features. major main management practices, and the level of impairment of the activities of daily living (ADL) of patients with back pain, 2) to test the sensitivity of the Korean Pain Rating Scale and the Graphic Rating Scales, and 3) to identify indirect indicators of back pain by analysing pain related-behaviors. The level of pain was measured by Korean Pain Rating Scale(KPRS) and Graphic Rating Scales(GRS) developed by the reserchers. The GRS consists of two dimensions; the pain intensity (sensory) and unpleasantness (affective) measures. Of the 1,650 diagnosed back pain patients, from January 4 through June 30, 1987 by visiting outpatients' clinics of orthopedic and neurosurgical departments at 11 university hospitals in different districts of Korea, 330 men and women patients were self-selected by responding to the mailed questionnaires. The results were summarised as follows: Male exceeded female patients in number and onset of back pain were more prevalent in the age groups of 20s and the 30s. The average duration of suffering from the pain were 11 months, sixty three (19.1%) of the subjects retired from their jobs, one third(36.7%) have teen hospitalized for the treatment of back pain. In two thirds(64.8%) of the cases pain was characterized as lower back pain. The average sleep hour was 6.8 hours per 24 hours and the average rest hour during the day was 3.3 hours. The mean percentage of pain measured by GRS was higher than that of KPRS. The level of sensory intensity as well as the affective level of pain measured by KPRS and GRS were not highly correlated (sensory intensity r=0.4986, affective r=0.5029) which indicated low discriminative power. On the other hand, intercorrelation between sensory and affective dimension measured by KPRS and GRS showed moderate interrelation(r=0.7247; r=0.7899). One-third(32.5%) of the subjects complied with the hospital prescribed treatment while the other one-third(31.5%) depended on self-remedy and traditional practices, and the last one-third did not imply any pain management practices. The following 6 pain-related behaviors such as length of hospitalization, rest hour during day hours, varieties of pain management practice implied, number of pain sites, need for ADL and discomfort accompanied by ADL revealed to be important indicators of back pain. An investigation of sociodemographic features of patients with back pain in a larger context, i.e. with bigger number of respondents is recommended. Tests for construct validity of KPRS, i.e. factor analysis is further recommended.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.3
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• pp.325-330
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• 2010

This study was conducted to investigate the effects of 70% ethanol extracts of various germinated-rough rice cultivars: ('Ilpum', 'Goami2', 'Keunnun', 'Sulgaeng', 'Baegjinju', and 'Heugkwang') on proliferation of human cancer cell lines (MKN-45, HCT116 and NCI-H460). Antiproliferation effects of rough rice on different cancer cell lines were higher in after germination than before germination. The viability of HCT-116 colon cancer cells was lowest at 18.89% in after germination of 'Heugkwang' at 1.0 mg/mL. The cell viability of MKN-45 lung cancer cells and MKN-45 stomach cancer cells were in the range of 5~10% in after germination of 'Ilpum', 'Goami2', 'Baegjinju', and 'Sulgaeng', and 'Heugkwang' at 1.0 mg/mL. These results suggest that germinated rough rice might have a potential preventive effect on human cancer cells.