• The Journal of Korean Academy of Prosthodontics
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• v.58 no.2
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• pp.77-85
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• 2020

Purpose: The aim of the present study was to investigate the effects of N-acetyl cysteine (NAC) loading on the bone formation surrounding sandblasted, large-grit and acid-etched (SLA) implants. Materials and methods: Implantation of NAC loaded SLA implants (NSI group) and SLA implants (SI group) was performed bilaterally in the mandible of 4 adult beagle dogs (each group, n = 8). The animals were sacrificed after a healing period of 3 and 6 weeks, respectively (n = 2 animal each). Dissected blocks were processed for histomorphometrical analysis. Bone to implant contact percentage (BIC%) and bone volume (BV%) were assessed histomorphometrically. Results: BIC% of NAC loaded SLA implants were about 50% higher than that of SLA implants at 3 weeks of bone healing, but not significantly (51.79 vs 35.43%; P=.185). BV% of NAC loaded SLA implants were significantly higher than that of SLA implants at 3 weeks of bone healing (45.09 vs 37.57 %; P=.044). At 6 weeks of bone healing, BIC% and BV% of two experimental groups were similar (P>.05). Conclusion: Within the limits of the present study, NAC loading have a positive effects on the early bone formation surrounding SLA implants. So, it might be concluded that NAC loading enhance the osseointegration and shorten the healing time after implantation of the SLA implants.

• Biomedical Science Letters
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• v.4 no.2
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• pp.143-151
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• 1998

To study the incidence and epidemiological factors of uterine cervical cancer in medical underserved area females, the questionnaire survey and Pap. smear for uterine cervical cancer was done on total 330 women who lived in Ullungdo from 5th to 12th August, 1998. The results were summarized as follows： The age distribution of subjects was 50s (24.5%), 60s (24.5%) and their educational level was “no schooling” (14.2%) and “elementary school” (42.7%). The first coital age of subjects was 19∼21yrs (30.0%), 16∼18yrs (13.9%) and the first pregnancy age was 22∼24yrs (36.7%) and 19∼21yrs (30.0%). The frequency of total pregnancy of subjects was over 5 times (52.1%). The frequency of total delivery was “3∼4 times” (35.5％) and “5∼6 times” (15.2％). 68.8% of subjects had experience of abortion and 80.0% of their husband were on the phimosis. 172 (52.1%) subjects had gynecological symptoms, their symptoms were leukorrhea (48.3%), pruritus (21.5%) and leukorrhea with pruritus (20.3%). 63.9% of total subjects have been received Pap. smear and the frequency of their Pap. smear was “only 1 time” (44.1 ％), “irregularly” (30.3%) and the reason of respondents who have not been received Pap. smea. was “no specific symptom” (51.3%). Among the 330 women screened there were negative (45.8%), inflammation (47.3%), trichomoniasis and candidiasis (1.8%), atypical cells (4.5%) and dysplasia (0.6%).

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.442-450
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• 2011

Numerous studies have suggested that dietary flavonoids contribute to prevent cardiovascular disease. Onion contains many functional phytochemicals such as quercetin. The aim of this study was to examine whether onion peel extracts supplementation affect blood lipid profiles and blood coagulation in animal model. Total 48 Sprague-Dawley male rats at 5 weeks old were divided into 6 groups with different diets(C: control, HF: high fat diet, HFOE 0.01%: high fat+onion peel extract 0.01% diet, HFOE 0.02%, HFOE 0.05%, HFOE 0.1%) for 8 weeks. Onion peel extract supplementation significantly decreased serum levels of LDL-cholesterol and increased HDL-cholesterol, while total cholesterol and triglyceride levels were not affected. Hematological parameters(hematocrit, white blood cell, red blood cell, and platelet count) and blood coagulation parameters(prothrombin time, activated partial thromboplastin time, thrombin time, and fibrinogen) were not significantly different among 6 groups. However, activated partial thromboplastin time of HFOE 0.05% group was significantly longer than that of HF group. These results indicate that onion peel extract supplementation displays hypocholestrolemic effects but does not seem to have anti-coagulation effects in high fat fed SD rats.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.3
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• pp.75-85
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• 2009

This work proposes a 13b 100MS/s 0.13um CMOS ADC for 3G communication systems such as two-carrier W-CDMA applications simultaneously requiring high resolution, low power, and small size at high speed. The proposed ADC employs a four-step pipeline architecture to optimize power consumption and chip area at the target resolution and sampling rate. Area-efficient high-speed high-resolution gate-bootstrapping circuits are implemented at the sampling switches of the input SHA to maintain signal linearity over the Nyquist rate even at a 1.0V supply operation. The cascode compensation technique on a low-impedance path implemented in the two-stage amplifiers of the SHA and MDAC simultaneously achieves the required operation speed and phase margin with more reduced power consumption than the Miller compensation technique. Low-glitch dynamic latches in sub-ranging flash ADCs reduce kickback-noise referred to the differential input stage of the comparator by isolating the input stage from output nodes to improve system accuracy. The proposed low-noise current and voltage references based on triple negative T.C. circuits are employed on chip with optional off-chip reference voltages. The prototype ADC in a 0.13um 1P8M CMOS technology demonstrates the measured DNL and INL within 0.70LSB and 1.79LSB, respectively. The ADC shows a maximum SNDR of 64.5dB and a maximum SFDR of 78.0dB at 100MS/s, respectively. The ABC with an active die area of $1.22mm^2$ consumes 42.0mW at 100MS/s and a 1.2V supply, corresponding to a FOM of 0.31pJ/conv-step.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.354-364
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• 1983

Confonmation of (Z)-cinnamonitrile have been studied by molecular orbital theoretically using extended Huckel theory(EHT) and CNDO/2 molecular orbital calculation methods. The results indicate that the stability of conformation is(Z)-gauch>(Z)-planar. The rate constants for alkalie hydrolysis of cinnamonitrile at pH 7.0-14.0 range have been determined by ultra-violet spectrophotometry in 50% methanol at $25^{\circ}C$ and the following rate equation which can be applied over wide pH range was obtained; $${\therefore}k=({\frac{1.41{\times}10^{-14}+1.21{\times}10^7/[H_3O^+]}{2.65{\times}10^{-7}+1.64/[H_3O^+]})+9.14{\times}10^9/[H_3O^+]$$ The rate equation reveals that, at pH 7.0-10.0, the reaction is initiated by the addition of water molecule to unsaturated cabon-carhon double bond of cinnamonitrile and ${\alpha}C-{\beta}C$ bond scission follow subsequently in neutral and alkalie media. At pH 12.0-14.0, in strong alkalie solution, that so-called Michael type nucleophilic addition that the over-all rate constants is only dependent upon the concentration of hydroxide ion occurs competitively and are very complicated. Hence, the reaction mechanism of alkalie hydrolysis of cinnamonitrile which did not carefully before can be fully explained.

• Journal of dental hygiene science
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• v.10 no.3
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• pp.131-139
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• 2010

The purpose of this study was to evaluate smoking patterns, oral health behavior and perception of dental healthcare of military personnel in the South Korea Army. All 367 subjects were surveyed by the structured questionnaires with convenience sampling method. The questionnaires were consisting of 22 items. Depending on the conditions of military training, the distribution and differences of smoking patterns and oral behaviors were evaluated by frequency test, Weighted Kappa, Paired t-test and ANOVA. The differences of oral health perception on smoking were demonstrated by Mantel-Haenszel Chi-square test. In addition, Generalized Estimating Equation (GEE) was used to estimate the effects of oral behavior for the conditions of military training and smoking. The number of cigarette during military training period was similar to that during non-military training (p=0.109). The perception of smokers such as smoking effect on oral health, oral health and systemic health, and need of education for smoking cessation was significantly lower than non-smokers (p=0.0095, p=0.0007, and p<0.0001). The probability that toothbrush frequency per day was only one was associated with higher during military training period than non-military training (OR=9.29, 95% CI 5.05-17.07). Moreover, the probability that hours of toothbrush were less than one minute was associated with higher during military training than non-military training (OR=2.19, 95% CI 1.78-2.71). To improve knowledge, attitude, and behavior of oral health for the members, the army needs to develop oral health education and tobacco cessation programs. In particular, motivation and practice for oral health care are required to improve poor oral health behavior during the military training.

• Korean Journal of Environment and Ecology
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• v.27 no.6
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• pp.765-776
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• 2013

This study was conducted to find out availability of a urban forest (Eudeungsan) as a substitute place of Mudeungsan Provincial Park (MPP) in overuse problem and to identify related factors to place substitutability. During June-August of 2012, 232 samples who have ever visited both of the two places (i.e., MPP and Euduengsan) in Gwang-ju city were selected by using convenient sampling and snowball sampling methods. Self-administered questionnaire survey was conducted, and the valid responses from 225 samples (97.0%) were used for data analysis. 24.2% of respondents had "considerably" or "very much" intention to use the substitute place, and 65.5% of respondents showed "a little" or "somewhat" 10.3% of respondents didn't have any intention to visit Eudeungsan as a substitute place of MPP. Generally, socio-demographic and visiting characteristics were not related with intention to visit Eudeungsan as a substitute place of MPP. It was only found that respondents who largely visit 'alone' to Eudeungsan tended to have higher intention to visit the substitute place than those who visit 'in group.' Three factors of reasons to visit Eudeungsan (i.e.,Challenge/self-development: ${\beta}=0.35$; Accessibility/familiarity: ${\beta}=0.27$; Adventure: ${\beta}=-0.19$) influenced intention to visit the substitute place. Relationship between reasons to visit and intention to visit the substitute place was found. No direct relationship was found between perceived similarity of the places and intention to visit substitute place, and similarity of recreation experiences showed perfect mediating effects between the two variables.

• Korean journal of applied entomology
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• v.51 no.3
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• pp.271-280
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• 2012

Twenty-two families and 39 species of insect pests were surveyed on five families and 20 species of greenhouse vegetables in Jeonbuk province. The species of insect pests and the families of plants infested were seven families and 10 species on Chenophodiaceae, 16 families and 25 species on Brassicaceae, nine families and 10 species on Apiaceae, six families seven species on Liliaceae, and 13 families and 29 species on Compositae. Spodoptera exigua H$\ddot{u}$bner and Spodoptera litura Fabricius occurred on all vegetables. Additionally, Frankliniella intonsa Trybom, Trialeurodes vaporariorum Westwood, Myzus persicae Sulzer, and Phytomyza horticola Goureau occurred on all vegetables except Liliaceae(Allium tuberosum Rottl. and Allium fistulosum L.). Thirteen species of insect pests including Hymenia recurvalis Fabricius occurred only one vegetables, indicating that they were monophagous. The main insect pests of Chenophodiaceae were M. persicae, H. recurvalis, S. exigua and S. litura whereas Dolycoris baccarum Linn$\acute{e}$, Trialeurodes vaporariorum Westwood, Trichoplusia ni H$\ddot{u}$bner, and P. horticola were not recorded. On Brassicaceae were Brevicoyne brassicae Linn$\acute{e}$, M. persicae, Phaedon brassicae Baly, Phyllotreta striolata Fabricius, Plutella xylostella Linn$\acute{e}$, Hellula undalis Fabricius, S. litura, Pieris rapae Linn$\acute{e}$, Artogeia rapae Linn$\acute{e}$, and Athalia rosae ruficornis Jakovlev, but six species including Frankliniella intonsa Trybom were not recorded. The degree of damage by insect pests on Apiaceae was low, five species including Tetranychus kanzawai kishida, F. intonsa, T. vaporariorum, S. litura, and P. horticola were not recorded. The main insect pests on Liliaceae were Thyatira tabaci Lindeman, Acrolepiopsis sapporensis Matsumura, S. exigua, and Liriomyza chinensis Kato. The damage to Compositae by insect pests was relatively low except that of S. litura.

• The Journal of the Petrological Society of Korea
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• v.2 no.2
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• pp.74-94
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• 1993

Metabasites and metapelites in the Mungyong area were intruded by Cretaceous granites with radius of 4-8 km. As the distance from granite body increases, the mineral assemblage of metabasite changes from amphibole + plagioclase through amphibole + plagioclase + epidote to amphibole + plagioclase + epidote + chlorite. The compositional variations of amphibole and plagioclase according to the change of metamorphic grade and bulk rock compositions are very complex. Towards the Mungyong Cretaceous granite body, the mineral assemblage of metapelite changes from chlorite+ muscovite(ch1orite zone) through biotite + chlorite + muscovite(biotite zone) to andalusite+biotite + muscovite${\pm}$chlorite or cordierite+ biotite+ muscovite${\pm}$chlorite(cordierite zone). The estimated metamorphic conditions of cordierite zone are 480~$580^{\circ}C$ 1.5-3.3 kb. The theoretical study on the thermal metamorphism caused by the Cretaceous granite with radius longer than 4 km in the Mungyong area suggests the followings: The degree of metamorphism is mainly determined not by the size of granite body but by the temperature of granite intrusion; The country rocks within 2 km from Cretaceous granite have undergone metamorphism with temperature higher than $500^{\circ}C$, which is consistent with the petrological study in the Mungyong area. Mungyong Cretaceous granite caused a low P/T thermal metamorphism to the country rocks; the amphibolite facies metamorphism to the country rocks within 1-2 km from the granite body and the epidote-amphibolite and greenschist facies metamorphism to the country rocks within 2-5 km.

• International Journal of Highway Engineering
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• v.6 no.3 s.21
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• pp.1-7
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• 2004

Roads, like bikeways, parkways and walks, are to be just capable of supporting light traffic and traveling public, but they are required to be human friendly and environmental-oriented. Lately soil-solidifier mixture, a kind of soil-cement, has developed and has been applied to the recycling and environment-oriented pavement as the surfacing material. Soil-solidifier pavement structure has been designed by only experience. To design this pavement mechanically, it is necessary to find out basic engineering properties of soil-solidifier mixture. This study focuses on finding out mechanical characteristics of the mixture according to mixture proportions and aging. Test molds with various mixture proportions are made, and then unconfined strength tests are performed for test molds with aging of the mixture. As the result of this study, it is found that the strength of the mixture increases with amount of cement and that maximum strength is achieved at 6%$\sim$8% of the ratio of solidifier and water. The strength increase rapidly until 14 days, after then slowly. After 28 days the strength of the mixture approaches to the constant value. The heat of hydration during curing of the mixture is measured no significantly. It also shows that temperature characteristics of the mixture is similar to that of soil. Since this mixture is mixed with soil and is able to improve engineering problems in pavement due to temperature, this mixture is expected to use effectively in the environment-oriented pavement for light traffic.