• Journal of the Korean Chemical Society
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• v.18 no.2
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• pp.85-96
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• 1974

Extended H ckel Theory and CNDO/2 MO calculation methods have been applied to $C_6H_5YCH_2Cl$(Y = None, -$CH_2$-, -O-, -S-, -CO-, -$SO_2$-). It has been shown that charge distributions in molecules are mainly controlled by the migration of valence inactive electron, giving the order of ${\sigma}$-acceptor and ${\pi}$-donor effects -O- > -S- > -$CH_2$- > -$SO_2$-. The -CO- group exceptionally acts as ${\sigma}$-donor and ${\pi}$-acceptor. It was also predicted that, $S_N2$ reactivities of C$C_6H_5YCH_2Cl$ would be in the order of -O-${\thickapprox}$-CO- >>-S-${\thickapprox}$None > -$CH_2$-, neglecting solvent effect. From the results of our studies, we conclude that the structural factors influencing 의 $S_N$ reactivities will be: (1) positive charge developments on reaction center carbon atom (2) energy level of ${\sigma}$-antibonding unoccupied MO with respect to C-Cl bond. (3) ${\sigma}$-antibonding strength of C-Cl bond at that level.

• Journal of the Korean Magnetics Society
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• v.9 no.2
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• pp.111-120
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• 1999

The effects of annealing in rotating magnetic field after deposition on electromagnetic properties of $Co_{82}Zr_6Mo_{12}$ thin (200~1200 $\AA$) films prepared by RF-magnetron sputtering were investigated in terms of microstructure and surface morphology. The coercivity decreases, but $4{\pi}M_5$ does not change with increasing the film thickness. The coercivity of the films was decreased below 300 $^{\circ}C$ due to stress relief and decreasing the surface roughness, while increased at 400 $^{\circ}C$ due to partial grain growth. And then, $4{\rho}M_5$ was almost independent of annealing temperatures below 200 $^{\circ}C$, but increased from 7.4 kG to 8.0 kG at 300 $^{\circ}C$ and at 400 $^{\circ}C$, which was caused by precipitation and growth of fine Co particles in the films. The electrical resistivity of films was decreased with increasing annealing temperatures and the magnetoresistance was a negative value of nearly 0 $\mu$$\Omega$cm. After annealing at 300 $^{\circ}C$, maximum effective permeability was 1200 to the hard axis of the thin films according to high frequency change. Considering the practical application of biasing layers of the films for magnetoresistive heads, optimal annealing conditions was obtained after one hour annealing at 300 $^{\circ}C$ in 400 Oe rotating magnetic field.

• Journal of the Korean Chemical Society
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• v.36 no.4
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• pp.477-484
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• 1992

Using semiempirical molecular orbital method, ASED-MO of extended Huckel Theory, we were investigated chemical bonds and electronic properties of Cu atom in a chain and a layer for Y123 and Y124 superconductors from VEP (valence electron population), DOS (density of state), and COOP (crystal orbital overlap population). In order to investigate environmental effects of Cu atom for Y123 and Y124 superconductors, we introduced charged cluster models with point charge and without point charge into our calculations. As a result of ASED-MO calculations, the Cu atom in the layer acts as electron acceptor and the Cu atom in the chain acts as electron donor for Y123 and Y124 superconductors. The oxidation state of Cu atom for Y123 and Y124 superconductors without point charge is higher in the chain than in the layer. The oxidation state of Cu atom in the layer for Y123 superconductor is higher than that in the layer for Y124 superconductor. The Cu atom in the layer and the chain for Y123 superconductor does not largely affect on the environmental effect. However, the Cu atom in the layer and the chain for Y124 superconductor does largely affect on it. Also, electron population and chemical bonding of Cu1-O4, Cu2-O4, and Cu1-Cu2 for Y123 superconductor are far different from Y124 superconductor.

• Journal of the Korea Convergence Society
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• v.10 no.9
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• pp.85-90
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• 2019

The purpose of this study was to investigate the effects of individual board game program (IBGP) on cognitive function and depression level in 7 elderly people with mild cognitive impairment(MCI). We used the mini-mental state examination korean version (MMSE-K), montreal cognitive assessment korean version (MoCA-K), and korean form of geriatric depression scale(KGDS). The results showed significant differences in MMSE-K before, after, and follow-up(p<0.05), and there were differences of orientation for time, place, and object and attention in before, after, and follow-up(p<0.05). MoCA-K showed differences in before, after, and follow-up assessments(p<0.01), and showed differences in visual construction skill, orientation, and short-term memory(p<0.05). Finally, there was a difference in depression level before, after, and follow-up of KGDS(p<0.01). Therefore, IBGP for the elderly can help improve the cognitive function, and based on this, it is expected that an advanced IBGP will be applied to improve orientation for time and place in the elderly.

• Journal of Animal Science and Technology
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• v.49 no.1
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• pp.59-66
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• 2007

Sixty-seven Hanwoo calves were allocated into two groups, 27 spring calves (SC) and 40 fall calves (FC) to investigate the effects of calving season on water and nutrient intakes, growth performance and disease occurrence for the nursing and the post-weaning period. Mean DMI of 3 to 4 mo old FC was lower than that of SC due to low temperature in winter for FC. Water intake was higher for FC (birth to 1 mo old) but lower for SC (2 to 4 mo old) than the others. Mean BW did not differ between SC and FC, but average daily gain for over 2 mo old SC were significantly higher than FC. Diarrhea was mainly observed when the calves were before 60 d old; in particular, it occurred more frequently for less than 30 d old FC compared with SC. The present results indicate that calving season may affect water intake, feed intake and growth performance of Hanwoo calves.

• Economic and Environmental Geology
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• v.45 no.3
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• pp.217-235
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• 2012

We evaluated the geochemical characteristics and their potential pollution of Asian Dusts in Daejeon, Korea during spring 2007. Compared with the chemical compositions of soils in source area of Asian Dust, those of aerosols in Daejeon were enriched with trace elements (ten to hundred fold), inferring that pollutants from China have affected on local environment in adjoining country such as Korea. Chemical analysis of aerosols during Asian dust showed that fine particles ($PM_{2.5}$) contained high contents of trace elements such as Cr, Cu, Pb, Zn, V, S, As, Cd, Co, Ni, Mo, Sb, Cs, Rb, Th, Sc and Y. In the case of TSP (Total Suspended Particle), Zr, Sr, Ba, Li, Th and U were contained much more than other trace elements. The contents of some elements (i.e. Li, Cs, Co, U, Cr, Ni, Rb, V, Th, Y, Sr and Sc) in aerosols collected in Asian Dust period, which are not likely enriched by air pollutants, were higher (2 - 4.2 fold) than those in Non Asian Dust period, indicating that these elements could be used as indicator elements for determining the occurrence of Asian Dust phenomena (especially, Sr, V, Cr & Li). In the case of Asian Dust coming through the big cities and/or industrial areas of China, the domestic aerosols had higher contents of trace elements (such as S, Cd, Zn, Pb, Cu, Mo and As) than those from Northeastern China via North Korea, indicating that the transportation courses of air mass are very important to determine the pollution degrees. Using the enrichment factors of trace elements in aerosols during Asian Dust and Non Asian Dust, we identified that some elements (i.e. S, Zn, Cu, Pb, As, Mo and Cd) were most problematic in terms of environmental hazard aspects, and these elements could affect adverse effects on human health as well as ecosystem and surface environment (soil and water) through long-lived precipitation.

• The Journal of Korean Medicine
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• v.36 no.1
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• pp.9-21
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• 2015

Objectives: Realgar has been frequently used for skin disorders in history of herbal medicine. However, the efficacy of realgar has not been examined in atopic dermatitis(AD). In this study, the effects of realgar on AD were investigated, especially on pruritus and inflammation. Methods: AD lesions were induced in the shaved backs of BALB/c mice through repeated application of DNCB. The mice were treated for 11 days with 1% realgar ($100{\mu}L/day$). Histological changes in skin thickness were observed. The anti-pruritic effects of realgar were evaluated by the change in numbers of scratching behavior of mice and expression of substance P. The expressions of cytokines IL-4 and IL-6 were measured. Also, anti-inflammatory effects of realgar were examined on expressions of NF-${\kappa}B$, phospho-$I{\kappa}B{\alpha}$ and mitogen-activated protein kinases (MAPKs). Results: Realgar decreased skin thickness (both dermal and epidermal) 38% and 17% respectively, compared to positive control, DNCB group. The scratching behavior of mice was reduced by 42% and expression of substance P was significantly less. Cytokines IL-4 and IL-6 were significantly reduced by 52.6% and 77.6%, respectively. The expressions of NF-${\kappa}B$, phospho-$I{\kappa}B{\alpha}$ and MAPKs (phospho-ERK1/2, -p38 and -JNK) were significantly suppressed with marked effects on phospho-ERK1/2. Conclusions: The collective results suggest that realgar shows anti-pruritic and anti-inflammatory effects on AD. And realgar might be a potential therapeutic candidate for treatment of atopic dermatitis.

• The Journal of Korean Medicine
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• v.37 no.1
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• pp.10-20
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• 2016

Objectives: Poncirus trifoliata Rafinesque has been known to have anti-allergic effects in skin diseases. However, anti-atopic dermatitis effects of P. trifoliata Rafinesque have not been studied yet in skin diseases. The present study evaluated the anti-atopic dermatitis effects of P. trifoliata Rafinesque (PTR) using external treatments on AD. Methods: AD lesions were induced by the repeated application of 2, 4-Dinitrochlorobenzene (DNCB) on the shaved back of BALB/c mice. $100{\mu}{\ell}$ of PTR extracts was applied to the AD lesions for 11 days. Histological assessments, mast cells count and serum levels of IgE were analyzed. The anti-pruritic effects of PTR were examined by the change of scratching frequency and nerve growth factor (NGF) expression. In addition, the anti-inflammatory effects of PTR were examined by the expressions of Th2/Th1 cytokines and pro-inflammatory in dorsal skin. Results: Histopathological findings showed that topical application of PTR decreased the thickness of dermal and epidermal skin compared with the DNCB group. PTR also notably decreased the mast cells count and serum IgE. The scratching behavior of mice and expression of NGF were significantly reduced. In addition, PTR group significantly suppressed the IL-4, IL-6, IFN-${\gamma}$ and TNF-${\alpha}$ cytokines compared to the DNCB group. Conclusions: These results indicated that P. trifoliata Rafinesque possess anti-pruritus and anti-atopic dermatitis properties. Therefore, P. trifoliata Rafinesque might be used for treatment of pruritus and atopic dermatitis.

• The Journal of Korean Medicine
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• v.20 no.3 s.39
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• pp.105-114
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• 1999

To investigate the anti-complementary and cytotoxic effects of oriental prescription, Kuseonwangdogo, on the proliferation of preadipocyte 3T3- L1 cells, we examined biological effects of Kuseonwangdogo. The results obtained were as follows. 1. After 14 days, the body weight of rats treated with Kuseonwangdogo decreased more than that in the control group (p<0.05). However, the weights of liver, spleen and kidney were unchanged. In serum biochemical test, we examined the level of glucose (GLU) and glutamic pyruvic transaminase (GPT). The levels of GOT and CHOL in serum were decreased remarkably by the administration of Kuseonwangdogo (p<0.05). The haematological examination of the tested group showed significant increment of white blood cells (WBC), hemoglobin concentration (HGB), mean corpuscular hemoglobin (MCH) and monocyte (MO). 2. The effect of Kuseonwangdogo on the proliferation of 3T3-L1 cells was tested by the sulforhodamin B(SRB) assay. The high concentration ($100{\mu}l\;and\;200{\mu}l$) of extracts inhibited the proliferation of 3T3- L1 cells. The p-value was <0.01, respectively. 3. The extract of Kuseonwangdogo showed a potent anti -complementary activity. It was suggested that the active principle may be a kind of polysaccharide molecule. 4. The cytotoxic effects of Kuseonwang dogo and its composing herbs in human liver cells (WRL68) and monkey kidney cells (Vero) were examined by the SRB and 3- (4,5- Dimethylthiazol-2-yl) -2,5 diphenyl-2H- tetrazolium bromide (MTT) assay. Cytotoxic effects were not observed.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.4
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• pp.503-513
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• 2014

This study investigated the effects of dietary consciousness of gender and generation on food intake frequency in Daegu, Sangju, Kimchen and Gumi. There was a total of 359 subjects, which consisted of elementary students, college students, and adults. The survey period was from March to May 2011, and it was a self-questionnaire by convenience sampling. The results were as follows: 1. A 9 point scale on intake frequency of 59 kinds foods was classified into 17 groups. Gender had significant differences on intake frequency of meats, beans, root vegetables, tuber vegetables, fruit vegetables, mushrooms, nuts, liquors, and cola. Sixteen food groups, except for fats, showed significant differences in intake frequency by generation. 2. Dietary consciousness consisted of 15 items, and it was divided into nutritional consciousness and meal consciousness. Meal consciousness was significantly higher in females than in males, as well as college students and adults than in elementary students. 3. Nutritional consciousness had significant effects on intake frequencies of grains, leaf vegetables, root vegetables, fruit vegetables, milk and milk products, fat and fatty oils. Meal consciousness had effects on intake of grain, leaf vegetables, root vegetables, seaweeds, teas and coffee. 4. Meal consciousness of males had significant effects on intake frequencies of grains, leaf vegetables, root vegetables, seaweeds, teas, and coffee. Elementary students showed significant effects on grains, leaf vegetables, root vegetables and seaweeds.