• Journal of Nutrition and Health
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• 제38권2호
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• pp.117-124
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• 2005

We investigated the effects of prolonged exposure in hot environmental condition and ingestion of fluid on various physiological variables including plasma glucose, lactate, the rating of perceived exertion (RPE), and heart rate as well as golf putting performance. Six male professional golfers were voluntarily participated in three different putting trials which were separated by seven days of time interval period. Three different putting trials were conducted at either 20℃ or 32℃, or 32℃ + Fluid ingestion. Performing 32℃ + Fluid ingestion trial, all subject ingested sport drink as much as their body mass was decreased. For each experiment, all subjects were undertaken total 48 putting, which separated by four x 12 putting in four different time points (i.e., Rest, 1 hr, 2 hr, and 3 hr). Plasma glucose concentration was significantly decreased with hot ambient condition but it was almost fully recovered by fluid ingestion. Plasma lactate concentration was significantly higher when subjects were exposed in hot environmental condition, and it did not change with fluid ingestion. There was a no different in putting performance and psychological fatigue level (performed by GRID test) at any environmental conditions. The RPE, commonly used for evaluating of physical fatigue level, was significantly dropped by fluid ingestion which indicates lower physical fatigue level. In addition to this, heart rate (HR) was also significantly decreased after fluid ingestion. Based on these results, it was concluded that the ingestion of fluid during prolonged exposure in hot ambient condition decrease the degree of physical fatigue levels and heart rate, which will possibly improve the golf performance when exposed in extreme weather condition in summer. (Korean J Nutrition 38(2): 117～124, 2005)

• 한국산학기술학회논문지
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• 제12권3호
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• pp.1145-1150
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• 2011

본 연구는 발달적 위기에 놓여있는 중년여성의 피로와 스트레스 저항력 그리고 정서와의 상관관계를 알아보기 위하여 뇌신경 생리학적 지표인 뇌파측정을 이용하여 분석해 보고자 하였다. 2005년 3월부터 2009년 6월까지 한국정신과학연구소에 뇌파측정을 의뢰한 우리나라 중년여성 4402명(35세~65세)의 뇌기능 지수(긴장도, 항스트레스지수, 정서지수)를 시계열 선형분석과 상관분석으로 한 결과 중년여성의 피로, 스트레스 저항력 그리고 정서 사이에는 유의한 관계가 있었다. 또한 정서적 성향을 보면 명랑과 우울 성향에서는 명랑 성향이, 긍정과 부정적 성향에서는 긍정적 성향이, 전체적으로는 명랑하면서 긍정적인 성향이 많은 것으로 나타났다. 그러므로 중년여성들의 피로와 스트레스를 감소시켜 삶의 질을 높이는 것이 개인건강은 물론 원만한 가족의 안녕을 유지, 증진하는데 꼭 필요하다고 본다.

• Elastomers and Composites
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• 제55권2호
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• pp.81-87
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• 2020

Service life prediction and evaluation of rubber components is the foundational technology necessary for securing the safety and reliability of the product and to ensure an optimum design. Even though the domestic industry has recognized the importance thereof, technology for a systematic design and analysis of the same has not yet been established. In order to develop this technology, identifying the fatigue damage parameters that affect service life is imperative. Most anti-vibration rubber components had been damaged by repeated load and aging. Hence, the evaluation of the fatigue characteristics is indispensable. Therefore, in this paper, we propose a method that can predict the service life of rubber components relatively accurately in a short period of time. This method works even in the initial designing stage. We followed the service life prediction procedure of the proposed rubber components. The weak part of the rubber and the maximum strain were analyzed using finite element analysis of the rubber bushing for the tracked vehicles. In order to predict the service life of the rubber components that were in storage for a certain period of time, the fatigue test was performed on the three-dimensional dumbbell specimen, based on the results obtained by the rubber material acceleration test. The service life formula of the rubber bushing for tracked vehicles was derived using both finite element analysis and the fatigue test. The service life of the rubber bushing for tracked vehicles was estimated to be about 1.7 million cycles at room temperature (initial stage) and about 400,000 cycles when kept in storage for 3 years. Through this paper, the service life for various rubber parts is expected be predicted and evaluated. This will contribute to improving the durability and reliability of rubber components.

• Safety and Health at Work
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• 제10권3호
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• pp.321-326
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• 2019

Background: Performing cognitive tasks and muscular fatigue have been shown to increase muscle activity of the lower extremity during quiet standing. A common intervention to reduce muscular fatigue is to provide a softer shoe-surface interface. However, little is known regarding how muscle activity is affected by softer shoe-surface interfaces during static standing. The purpose of this study was to assess lower extremity muscular activity during erect standing on three different standing surfaces, before and after an acute workload and during cognitive tasks. Methods: Surface electromyography was collected on ankle dorsiflexors and plantarflexors, and knee flexors and extensors of fifteen male participants. Dependent electromyography variables of mean, peak, root mean square, and cocontraction index were calculated and analyzed with a $2{\times}2{\times}3$ within-subject repeated measures analysis of variance. Results: Pre-workload muscle activity did not differ between surfaces and cognitive task conditions. However, greater muscle activity during post-workload balance assessment was found, specifically during the cognitive task. Cognitive task errors did not differ between surface and workload. Conclusions: The cognitive task after workload increased lower extremity muscular activity compared to quite standing, irrespective of the surface condition, suggesting an increased demand was placed on the postural control system as the result of both fatigue and cognitive task.

• Journal of Acupuncture Research
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• 제34권2호
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• pp.83-91
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• 2017

Objectives : Alpiniae oxyphyllae Fructus (AOF) is an herbal medicine, which has been used for the treatment of fatigue, chills, and poor physical conditions. The objective of this study was to investigate the anti-inflammatory and anti-oxidative effects of AOF hot aqueous extract. Methods : The cytotoxicity of AOF extract was evaluated using the MTT assay. Nitric oxide (NO) production was measured by the Griess reaction. Prostaglandin $E_2$ ($PGE_2$) production was measured by a commercial competitive enzyme immunoassay. Cytokine production (IL-1tion co6, and TNF- F- was measured by ELISA. The anti-oxidative effect of AOF extracts was measured by the DPPH method. Polyphenol and flavonoid contents were measured by Folin-Ciocalteu's phenol reagent and aluminum chloride, respectively. Results : AOF hot aqueous extract did not show toxicity at doses of 25, 50, 100, and $200{\mu}g/mL$. AOF extract significantly inhibited NO production at doses of 100 and $200{\mu}g/mL.PGE_2$ production was inhibited by AOF extract treatment at doses of 100 and $200{\mu}g/mL$. AOF extracts reduced IL-6 production in a dose-dependent manner. IL-1ent maTNF- F- 1ent mannerd IL-6 production in uction at doses of 100 and ${\mu}g/mL$. The DPPH free radical scavenging capability was above 50% at $200{\mu}g/mL$. Conclusion : This study suggests that AOF hot aqueous extract may exert anti-inflammatory and anti-oxidative effects in a dose-dependent manner. Further studies are required for validating the safety and efficacy of AOF.

• Preventive Nutrition and Food Science
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• 제22권3호
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• pp.241-245
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• 2017

Aged garlic has been reported to possess beneficial pharmacological activities, including anti-stress and anti-fatigue properties, and to exert protective effects on the cardiovascular system and liver. Pine needles are widely used in folk medicine and as food additives owing to their pharmacological properties such as anti-aging and anti-inflammatory effects. It has long been known that combining certain phytochemicals with other phenols or organic acids can produce synergistic effects. Therefore, the purpose of this study was to develop an optimal formula of aged garlic with added pine needle powder for improved antioxidant activity using the statistical technique of response surface methodology. The antioxidant activities of aged garlic mixed with pine needle powder were confirmed by measuring oxygen radical absorbance capacity and total polyphenol content. An optimized antioxidant formula was identified that contained 5.08 g aged garlic and 1.97 g pine needle powder. The antioxidant activities of the mixture prepared using this optimal formula were significantly higher than the predicted values according to an additive model. Hence, this study confirms that the addition of pine needle powder to aged garlic can improve its antioxidant activity. This study demonstrated an optimal mixing ratio to produce an aged garlic product with improved functionality through the addition of pine needle powder that could be successfully employed by the food industry to prepare functional foods.

• Advances in Traditional Medicine
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• 제4권1호
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• pp.1-8
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• 2004

Ginseng root has been used as a tonic remedy in Traditional Chinese Medicine for centuries. Modern studies have demonstrated that ginseng root has complex components and multiple pharmacological properties. The effects of ginseng leaf, however, are not well known. Recent studies show that compared to ginseng root, ginseng leaf and stem exhibit a higher content of active compositions such as ginsenosides, polysaccharides, triterpene flavonoids, volatile oil, polyacetylenic alcohols, peptides, amino acids and fatty acids. Ginseng leaf possesses multiple pharmacological effects in the central nervous, cardiovascular, growth and metabolism systems. Additionally, the leaf has anti-fatigue, anti-hyperglycemic, anti-oxidant, and anti-aged effects. In general, ginseng leaf is quite safe, but adverse effects may occur if it is abused or is of poor quality. Thus, attention must be paid to dosages, quality, and standardization of ginseng leaf products.

• 한국한의학연구원논문집
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• 제17권2호
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• pp.135-167
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• 2011

Objective : To establish the fundament for EBM of Traditional Korean Medicine, the papers on Bojungikgitang(Buzhongyiqi-tang) frequently used in medical institutions of Traditional Korean Medicine were analyzed through researching domestic and international papers. Methods : The papers were classified by the registration of domestic or international journals, the year of publishment, experimental fields and the kinds of studies on biological activities. Results : Among 2005 volumes of papers on Bojungikgi-tang(Buzhongyiqi-tang), 219 volumes were selected according to selective criteria. 71 volumes were published in domestic journals, 52 volumes were in Chinese journal, 96 volumes were in Japanese journal. The papers on instrumental analyses reported the quantification of standard compounds of herbal medicines in Bojungikgi-tang(Buzhongyiqi-tang) using HPLC method. The papers on biological activities of Bojungikgi-tang(Buzhongyiqi-tang) showed mainly immune regulation, anti-infection, anti-cancer, gastrointestinal activity, neuropsychiatric regulation, anti-inflammation, hepatoprotection, musculoskeletal regulation. Among biological activities, papers on immume regulation were reported mostly. Conclusions : The efficacy of Bojungikgi-tang(Buzhongyiqi-tang) could be related to immune regulation, gastrointestinal activity, anti-fatigue and further study need to be preceeded to establish the fundament for EBM of Bojungikgitang(Buzhongyiqi-tang).

• Preventive Nutrition and Food Science
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• 제20권2호
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• pp.133-136
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• 2015

Freshwater softshell turtle (Trionyx sinensis) extract has been used traditionally as a tonic soup, and to recover from physical fatigue. To support these claims, the forelimb grip strength of mice was measured after feeding a soft-shell turtle extract for 7 days. The T. sinensis extract significantly increased the grip strength to $1.25{\pm}0.07N$ (P<0.01), which is 16.8% higher than the force on day 0. After exercising, the blood glucose levels in extract-fed mice were 202% higher and urea levels were 73% lower, which were both significantly different than the levels observed after control treatment. Lactate dehydrogenase was significantly higher by 314%, and glutathione peroxidase increased by 165%. In addition, the obesity markers, serum triglyceride and cholesterol, decreased to 62% and 49%, respectively, after mice were fed the extract. These data show that the T. sinensis extract provided more energy for forelimb exercise, prevented protein catabolism and muscle fatigue, and decreased the oxidative stress caused by an exhaustive workout.

• Advances in nano research
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• 제14권1호
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• pp.17-25
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• 2023

Gold nanoparticles have recognized a promising drug carriers in many diseases. These nanoparticles could carry anti-inflammatory drugs in the case of muscle injury and for fatigue relief. On the other hand, specific surface of this kind of nanoparticles could be critical in amount of drug they could carry. Therefore, in this study, we explore different methodology and influencing parameters on the specific surface of gold nanoparticles. After specifying the main parameters, different machine learning and artificial neural network are adopted to model the effects of different parameters. Furthermore, response surface methodology is utilized to obtain a quadrilateral relationship between different parameters and specific surface. The results indicate that concentration of the gold salt solution is the most important parameter in increasing the size of gold nanoparticle and, as a consequence, increasing specific surface. Moreover, the ability of gold nanoparticles in prolonging retention of the drugs is discussed in detail.