• 한국환경보건학회지
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• 제40권6호
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• pp.484-491
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• 2014

Objectives: A radon emission reducing agent was prepared using charcoal and zeolite, and the amount was measured after coating construction materials with the agent. The availability of the radon emission reducing agent was evaluated. Methods: Construction materials (red brick, cement brick, and gypsum board) coated with reducing agent were placed in a chamber to measure radon emissions. The construction materials were coated one through three times. The spread volume for brick and gypsum board was 50 mL and 75 mL per application, respectively. The amount of radon emitted was measured by RAD-7 after 48 hours. Results: The reduction ratio increased with the number of coatings, and the reduction ratios for red brick, cement brick, and gypsum board were 63.3, 73.6, and 58%, respectively, in the case of three coatings of RA-1. The reduction ratios for red brick, cement brick, and gypsum board were 42.8, 58.1, and 26.2%, respectively in the case of three coatings with RA-2. RA-1 was slightly better than RA-2 in radon emission reduction. Conclusions: Radon emissions from construction materials decreased according to the concentration of reducing agent coating, and it was more effective than existing methods.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.210-211
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• 2017

According to KS F 2560, water-reducing agents used when mixing concrete are to undergo quality evaluation testing slump, air contents, setting time, etc., when delivered from the admixture factory to the ready mixed concrete site. Yet in actual acceptance testing this could be substituted by the score report of the admixture company, in which a possibility of low reliability lies. Therefore this study sought to analyze whether by artificially changing the solid content rate of lignin- and naphthalene-based water-reducing agents and using a liquid densimeter evaluate the quality of the admixture. The results showed that the Type B liquid densimeter was most appropriate and 50cc the most appropriate capacity for the mass cylinder. Also, judging from the changes in density and pH according to the changes in solid content rate, it concludes that a rapid appraisal of the quality of lignin- and naphthalene-based water-reducing agents would be possible using a Type B liquid densimeter.

• 한국식품영양과학회지
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• 제23권1호
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• pp.73-77
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• 1994

This study was conducted to investigate and make comparison between treatment which was reduced the reducing sugar content from Chinese cabbage using salting and desalting processes prior to Kimchi fermentation , and control for the effect of reducing sugar content on Kimchi fermentation at $25^{\circ}C$. In the early stage of Kimchi fermentation , the amount of reducing sugar (5.7mg/ml) in treatment was much smaller than that (15.1mg/ml) in control. Reducing sugar content of treatment decreased drastically during the first two days and then levelled off . Whereas, that of control dropped significantly up to the first four days of fermentation. pHs of treatment and control decreased significantly during the first two days and then showed gentle slopes. Acidities of treatment and control were increased continuously during the entire range of fermentation . The acidity of control reached to 0.75% in 3 days of fermentation, while that of treatment was shown after 6 days. Hardnesses of treatment and control using a puncture test were almost constant and the hardness value of treatment was higher than that of control during whole fermentation period. The total bacteria and lactic acid bacteria counts increased drastically during the first day of fermentation and the increase of total bacteria counts was mainly caused by that of lactic acid bacteria counts.

• Journal of Ginseng Research
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• 제42권4호
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• pp.463-469
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• 2018

Background: Roots of Withania somnifera (WS) are a celebrated medicinal ingredient in Ayurvedic and many other indigenous systems of medicine. The present study investigates the effect of the phytochemical composition of the extracts on their antioxidant and reducing activities. Methods: WS roots were extracted with water, acetone, aqueous methanol (1:1), and methanol:-chloroform:water (1:1:1) to obtain aqueous, acetone, hydro-methanolic, and methanol-chloroform-water extracts. Thereafter, phytochemical constitution and antioxidant and reducing activities of the extracts were compared using different qualitative and quantitative tests. Results: Maximum extraction recovery was obtained with 50% aqueous methanol whereas extraction with acetone yielded the poorest recovery. Methanol-chloroform-water extract had the highest content of phytochemical constituents, except tannins, and also exhibited the highest antioxidant and reducing activities. Conclusion: Phytochemical composition and antioxidant and reducing activities of the extracts were positively associated with the use of organic solvents during the extraction process. Alkaloids and flavonoids were the most important contributors in the antioxidant and reducing activities of the extracts.

• 한국식생활문화학회지
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• 제36권3호
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• pp.256-264
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• 2021

The purpose of this study is to observe the influence education experience (home, school, and mass media) on reducing practice behavior(purchasing, using, disposing and leading) of food-related wastes. The study also sought to promote strategy and suggest effective activation plans for the vitalization of behavior of reducing food-related wastes. The study subjects were 412 adult consumers who answered a structured questionnaire. The main findings are as follows: First, the scores of home education experience were 3.61±0.71, which was the highest, and 3.45±0.74 for school education experience, which was the lowest. Second, according to factor analysis, the reducing practice behavior of food-related wastes was converged purchasing, using, disposing and leading behavior. The scores of disposing behavior were 3.79±0.67, which was the highest, and 2.87±0.82 for leading behavior, which was the lowest. Third, the common variables influencing the reducing practice behavior(purchasing, using, disposing and leading) of food-related wastes were home education and mass media and the powerful variable influencing was home education. The results of this study can be used as basic data for the development of educational programs for effective food-related waste reduction.

• Journal of Yeungnam Medical Science
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• 제39권3호
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• pp.200-205
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• 2022

Pain from nervous or musculoskeletal disorders is one of the most common complaints in clinical practice. Corticosteroids have a high pain-reducing effect, and their injection is generally used to control various types of pain. However, they have various adverse effects including flushing, hyperglycemia, allergic reactions, menstrual changes, immunosuppression, and adrenal suppression. Pulsed radiofrequency (PRF) is known to have a pain-reducing effect similar to that of corticosteroid injection, with nearly no major side effects. Therefore, it has been widely used to treat various types of pain, such as neuropathic, joint, discogenic, and muscle pain. In the current review, we outlined the pain-reducing mechanisms of PRF by reviewing previous studies. When PRF was first introduced, it was supposed to reduce pain by long-term depression of pain signaling from the peripheral nerve to the central nervous system. In addition, deactivation of microglia at the level of the spinal dorsal horn, reduction of proinflammatory cytokines, increased endogenous opioid precursor messenger ribonucleic acid, enhancement of noradrenergic and serotonergic descending pain inhibitory pathways, suppression of excitation of C-afferent fibers, and microscopic damage of nociceptive C- and A-delta fibers have been found to contribute to pain reduction after PRF application. However, the pain-reducing mechanism of PRF has not been clearly and definitely elucidated. Further studies are warranted to clarify the pain-reducing mechanism of PRF.

• 한국의류산업학회지
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• 제24권6호
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• pp.775-781
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• 2022

As part of research to develop a permanent wave-reducing agent for hair, in the current study, 0.1%-1.0% of Polyquaternium-10 was added to a permanent reagent containing Nicotinoyl Dipeptide-23 to prepare the agent, which was tested on damaged hair. The pH change was relatively stable even after a date, but due to the hair's natural composition, 0.1%-0.6% of the Polyquaternium-10 concentration according to pH was suitable. The temperature safety experiment demonstrated it to be stable at a high temperature and at room temperature, but when a Polyquaternium-10 concentration of 0.9% or higher was added at 0℃, coagulation occurred. In terms of the force efficiency of permanent wave formation, wave efficiency lowered as the concentration increased: the longer the wave lasts, the lower the Polyquaternium-10 concentration. The permanent moisture content was found to be higher as the concentration of Polyquaternium-10 increased. Therefore, when Polyquaternium-10 is applied to the permanent wave-reducing agent, considering stability, permanent formation, durability, and moisture rate, the most suitable concentration was found to be that of Polyquaternium-10 in the cysteine-reducing agent. A novel finding from this study is that as the concentration of Polyquaternium-10 increases, the consistency of the permanent wave-reducing agent changes, shifting from a liquid to a viscous liquid formulation.

• Journal of Acupuncture Research
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• 제29권5호
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• pp.151-158
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• 2012

Objectives : We hypothesized that reinforcing-reducing manipulations produce different effects by quantity of stimulation, and examined whether the difference is statistically significant or not. Methods : The study was conducted to the students of College of Oriental Medicine, Dongguk University. We needled into $ST_{36}$ and applied 6 kinds of basic reinforcing-reducing manipulations in Huang di nei jing by randomized sequence. And we had the students to fill up the questionnaire in form of visual analog scale(VAS). We examined whether significant differences in VAS existed between reinforcing-reducing manipulations(by t-test). And we examined whether significant differences in VDRRT(VAS difference between reinforcing-reducing technique) values existed along the gender, body mass index(BMI), age(by t-test), and psychological sensitivity(by ANOVA). Results : 1. The total stimulation quantity from reducing technique was significantly higher than that from reinforcing technique. Individually VAS values of reducing techniques were significantly higher in rotation, slow-rapid, lift-thrust, respiration and open-close manipulation. 2. The highest stimulation quantity was from rotation manipulation. And the highest VDRRT value was from slow-rapid manipulation. 3. When VDRRT values were analyzed by gender, age, BMI, and psychological sensitivity, VDRRT was significantly different by BMI in rotation manipulation, and by psychological sensitivity in rotation, lift-thrust, and slow-rapid manipulation. Conclusions : We could verify that reinforcing-reducing techniques induce different therapeutic effects by different quantities of stimulations. It suggests that reinforcing-reducing techniques could be applied universally, regardless of gender or age. Further studies are needed to consider control group, or patient groups in characteristic conditions.

• 미생물학회지
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• 제50권3호
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• pp.254-260
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• 2014

황화합물은 혐기성환경에서 혐기성호흡을 위한 매우 중요한 전자수용체이다. 본 연구를 통하여 한국의 다양한 습지에서 배양을 통한 황산염/황-환원세균의 특성연구를 실시하였다. 이를 분리하기 위하여 혐기성 roll tube법을 통해 총 11개의 순수 배양체를 확보하였다. 16S rDNA를 이용한 계통분석 및 상동성 분석을 실시하여 Desulfovibrio 속의 세균 8종, Sulfurospirillum 속의 세균 2종, Desulfitobacterium 속의 세균 1종을 얻을 수 있었다. 이들 황산염/황-환원세균은 모두 lactate와 pyruvate를 전자공여체로 이용하였으며, sulfite and thiosulfate를 전자수용체로 이용할 수 있었다. 앞으로, 다양한 전자공여체와 배양조건을 통하여 유용한 절대혐기성 황산염/황-환원세균의 생물자원 확보에 기여할 것으로 기대된다.

• 한국건축시공학회지
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• 제17권3호
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• pp.245-252
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• 2017

최근 소비패턴의 변화에 따라 대형마트, 아울렛 및 물류창고 등과 같은 구조물들이 증가하고 있다. 이와 같은 구조물들은 초평탄 바닥부재를 포함하고 있기 때문에 소성 및 건조수축에 의한 슬래브 부재의 균열 억제 관리를 철저하게 실시한다. 슬래브 부재의 균열을 억제하기 위한 방안으로 화학적 균열저감 방법을 사용하고 있으며, 특히 수축저감제에 대한 사용검토가 증가하고 있다. 그러나 이에 대한 국내 연구결과는 부족한 상황이다. 본 연구에서는 수축저감제를 사용한 콘크리트의 수축특성과 배합요인 변동에 따른 건조수축 특성을 검토하였다. 국내 수축저감제는 해외 고급형 수축저감제와 성능이 유사한 것으로 나타났으며, 수축저감제 사용량이 증가할수록 건조수축 억제 효과는 높아지는 것으로 나타났다. 수축저감제 1.5%를 사용한 시험체는 재령 100일에서 수축저감제를 사용하지 않은 시험체에 비해 건조수축량이 약 절반으로 나타났다. 또한, 혼화재료 사용에 대해 특별한 성능변화는 없는 것으로 확인되었다.