• International Journal of Oral Biology
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• v.45 no.2
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• pp.64-69
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• 2020

Short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate are secondary metabolites produced by anaerobic fermentation of dietary fibers in the intestine. Intestinal SCFAs exert various beneficial effects on intestinal homeostasis, including energy metabolism, autophagy, cell proliferation, immune reaction, and inflammation, whereas contradictory roles of SCFAs in the oral cavity have been reported. Herein, we found that low and high concentrations of SCFAs induce differential regulation of intracellular Ca²⁺ mobilization and expression of pro-inflammatory cytokines, such as interleukin (IL)-6 and IL-8, respectively, in gingival fibroblast cells. Additionally, cell viability was found to be differentially regulated in response to low and high concentrations of SCFAs. These findings demonstrate that the physiological functions of SCFAs in various cellular responses are more likely dependent on their local concentration.

• The Korean Journal of Physiology
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• v.29 no.2
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• pp.259-267
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• 1995

The renin-angiotensin system plays an important role in the regulation of blood pressure and in body fluid homeostasis. There is increasing evidence for generation of endogenous angiotensin II in many organs and for its role in paracrine functions. Studies were designed to investigate whether hemorrhage produces rapid changes in the gene expression of angiotensinogen in peripheral and brain tissues. Wistar rats received saline drinking water for 7 days, were bled at a rate of $3\;ml\;kg^{-1}\;min^{-1}$ for 7 min, and then decapitated 0, 2, 4, 8, or 24 hr after hemorrhage. Hemorrhage produced a produced hypotension with tachycardia at $2{\pm}8\;hr$, but blood pressure and heart rate had not fully recovered to the basal level at 24 hr. Plasma renin concentration was significantly increased at 2, 4, and 8 hr (maximum sixfold increase at 4 hr) and had returned to the basal level at 24 hr. Renal renin content was significantly increased only at 4 hr after hemorrhage. Angiotensinogen mRNA in both the kidney and liver were stimulated at 2 to 8 hrs, but recovered to the basal level at 24 hr. On the other hand, angiotensinogen mRNA levels il the hypothalamus and brainstem were continuously increased from 2 to 24 hrs. The present study demonstrates the presence of angiotensinogen mRNA in both hepatic and extrahepatic tissues, and more importantly, their up-regulation after hemorrhage. These results suggest that the angiotensinogen-generating systems in the liver, kideny and brain are, at least in part, under independent control and play a local physiological role.

• Human Ecology Research
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• v.54 no.4
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• pp.385-395
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• 2016

This study examines the effects of consumer socialization on Korean adolescent impulsive buying behavior. The current study used the third and sixth waves from the Korean Education and Employment Panel (KEEP) survey that has been administered by the Korea Research Institute for Vocational Education and Training since 2004. The subjects were high school juniors and university sophomores in 2006 and 2009, respectively. The final sample for panel regression analysis included 1,718 individuals. Two major agents of socialization (school and parents) were utilized in our model. Parent financial behavior (if the parents had savings) and the effectiveness/helpfulness of economics education in middle or high school were included in our estimation model. Two categories were included as individual factors: (1) psychological aspects and personal traits covering variables such as stress from self-image, academic stress, self-regulation, and a tendency of risky behavior and (2) financial behavior and attitudes, which include work experience, amount of money in hand, shopping habits, and if parental financial support is expected after high school graduation. The results from a random effects model revealed that the effects of consumer socialization through school was marginally significant, while through parents was not. Stress from self-image and the level of self-regulation were found to be significant. Neither risky behavior nor academic stress were a significant factor for impulsive buying behavior. The amount of money available in hand and shopping habits showed a significant influence. Implications for educators, parents and policy makers are identified.

• KIEE International Transaction on Systems and Control
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• v.12D no.1
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• pp.33-38
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• 2002

In this paper, the infinite time optimal regulation problem for weakly coupled bilinear systems with quadratic performance criteria is obtained by a sequence of algebraic Lyapunov equations. This is the new approach is based on the successive approximation. In particular, the order reduction is achieved by using suitable state transformation so that the original Lyapunov equations are decomposed into the reduced-order local Lyapunov equations. The proposed algorithms not only solve optimal control problems in the weakly coupled bilinear system but also reduce the computation time. This paper also includes an example to demonstrate the procedures.

• Journal of Forest and Environmental Science
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• v.29 no.2
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• pp.138-146
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• 2013

The typical natural landscapes and temporal- spatial regulation of Land use change and their ecological effects at Hailun County were conducted and analyzed, based on the translated data from remote sensing images in 1986, 1996 and 2000 using GIS and landscape ecological theory. The results indicated the area of arable land, paddy field and city land increased 7,786.39 $hm^2$, 3391.18 $hm^2$ and 120.84 $hm^2$ while the area of forestry, grassland and marsh decreased 3,184.88 $hm^2$, 1,625.8 $hm^2$ and 3,994.85 $hm^2$ respectively during 14 years. Dry land is a main landscape in this area. These changes made the environmental quality worse gradually, such as land degradation, soil erosion and water and soil losses, and temperature getting warmer. This study is very important for the local ecological environment protect and agricultural sustainability and land resources sustainable using.

• Archives of Plastic Surgery
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• v.46 no.3
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• pp.189-197
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• 2019

There has been an exponential increase in plastic surgery cases over the last 20 years, surging from 2.8 million to 17.5 million cases per year. Seventy-two percent of these cases are being performed in the office-based or ambulatory setting. There are certain advantages to performing aesthetic procedures in the office, but several widely publicized fatalities and malpractice claims has put the spotlight on patient safety and the lack of uniform regulation of office-based practices. While 33 states currently have legislation for office-based surgery and anesthesia, 17 states have no mandate to report patient deaths or adverse outcomes. The literature on office-base surgery and anesthesia has demonstrated significant improvements in patient safety over the last 20 years. In the following review of the proceedings from the PRS Korea 2018 meeting, we discuss several key concepts regarding safe anesthesia for office-based cosmetic surgery. These include the safe delivery of oxygen, appropriate local anesthetic usage and the avoidance of local anesthetic toxicity, the implementation of Enhanced Recovery after Surgery protocols, multimodal analgesic techniques with less reliance on narcotic pain medications, the use of surgical safety checklists, and incorporating "the patient" into the surgical decision-making process through decision aids.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.6
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• pp.714-720
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• 2003

Due to the electric power shortage in summer season and regulation of freon refrigerant, the application of gas absorption refrigeration and hot water systems are considerably increasing trend. But, this system consists of condenser, heat exchanger, supply pipe and radiator etc. which are easily corroded by acidity and dissolved oxygen and gases. In result, this system occurs scale attachment and corrosion damage like pitting and crevice corrosion. In this study, electrochemical polarization test of heat exchanger tubing material (copper, aluminium brass, 30% cupronickel(30% Cu-Ni)) was carried out in 60% lithium bromide solution at $95^{\circ}C$. As a result of polarization test, corrosion behavior by impressed potential and local corrosion. such as galvanic corrosion, pitting corrosion behavior, of tubing materials was investigated. The main results obtained are as follows: (1) The effect of pitting and crevice corrosion control of 30% cupronickel in 60% LiBr solution at $95^{\circ}C$ is very excellent. (2) Dissimilar metal corrosion of 30% cupronickel coupling to aluminium bronze is the most sensitive. (3) Current density behavior of tube materials by impressed potential is high in order of copper > aluminium brass > 30% cupronickel.

• Journal of Power Electronics
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• v.17 no.2
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• pp.464-475
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• 2017

This study examines a P+multi resonant-based voltage control for voltage harmonics compensation under the islanded mode of a microgrid. In islanded mode, the inverter is defined as a voltage source to supply the full local load demand without the connection to the grid. On the other hand, the output voltage waveform is distorted by the negative and zero sequence components and current harmonics due to the unbalanced and nonlinear loads. In this paper, the P+multi resonant controller is used to compensate for the voltage harmonics. The gain tuning method is assessed by the tendency analysis of the controller as the variation of gain. In addition, this study analyzes the slight voltage magnitude drop due to the practical form of the P+multi resonant and proposes a counter method to solve this problem by adding the PI-based voltage restoration method. The proposed P+multi resonant controller to compensate for the voltage harmonics is verified through the PSIM simulation and experimental results.

• Journal of Climate Change Research
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• v.9 no.3
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• pp.263-271
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• 2018

Considering the high needs of recipient countries and the regional biases of Korean Official Development Assistance (ODA) policy, increases in the total amount of ODA and allocation to the forest sector are needed for Central Asia. In Tajikistan, illegal harvesting and grazing cause a gradual decrease in forest area. The Tajikistan government conserves forests by requesting international cooperation and establishing a policy for sustainable management of forest resources and prevention of further damages. To suggest suitable strategies and plans, the current statuses of forests and forestry were investigated, and ODA projects that can illustrate successful Korean experiences of forestation were conceived based on various geographical features and local conditions of Tajikistan in this study. Forest resource creation type projects (fuelwood and Tugai forest restoration) could result in energy independence and enhancement of ecosystem service such as a climate regulation and an increase in biodiversity. Community development type projects (introduction of ecotourism, agroforestry, and planting of fruit trees) can contribute to job creation and encourage participation of local residents, thus improving their incomes. In addition, establishment of a project foundation, including education, training, and a national forest inventory, would help those projects be sustainable in the long-term.

• The Journal of Sustainable Design and Educational Environment Research
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• v.6 no.1
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• pp.1-24
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• 2007

Public library is established on impartial accessibility of any distinction as their sex, age, financial status, etc. The function of public library is not only to accumulate materials and offer information but also minimize gulf between the rich and the poor by knowledge possession, which is realized by important means to intercept exclusive possession and power in knowledge pose-industrial society. As it is judged that most public library is established to individual building with thousands of cost, it is judged of obstacles to Increase library buildings. The purpose of this study is try to find the way to Increase In number of public library In Seoul by interaction local education-cultural facilities. The result from this study, the user rate of public library is influenced by number of buildings and accessibility of traffic and public library can improve efficiency by substantial operation by basic function for all age group. The target population of Seoul public library sizes by decuple of advanced countries because of difficulty of accessibility, so it needs to make it small scale and also can offer self-regulation learning, materials and life-long learning programs because generally public library's utilization purpose is different by age. As school in Seoul amounts to 25 times of public library by about 1,200 buildings and can function of lifelong education center with a school library, cultural center and other composition buildings, so school facilities may use as a public library for local residents.