• Computers and Concrete
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• 제9권6호
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• pp.427-437
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• 2012

This article presents the effect of replacement fly ash (FA) with diatomite (DE) on the properties of geopolymer mortars. DE was used to partially replace FA at the levels of 0, 60, 80 and 100% by weight of binder. Sodium silicate ($Na_2SiO_3$) and sodium hydroxide (NaOH) solutions were used as the liquid portion in the mixture in order to activate the geopolymerization. The NaOH concentrations of 15M, $Na_2SiO_3$/NaOH ratios of 1.5 by weight, and the alkaline liquid/binder (LB) ratios by weight of 0.40, 0.50, 0.60 and 0.70 were used. The curing at temperature of $75^{\circ}C$ for 24 h was used to accelerate the geopolymerization. The flows of all fresh geopolymer mortars were tested. The compressive strengths and the stress-strain characteristics of the mortar at the age of 7 days, and the unit weights were also tested. The results revealed that the use of DE to replace part of FA as source material in making geopolymer mortars resulted in the increased in the workability, and strain capacity of mortar specimens and in the reductions in the unit weights and compressive strengths. The strain capacity of the mortar increased from 0.0028 to 0.0150 with the increase in the DE replacement levels from 0 to 100%. The mixes with 15M NaOH, $Na_2SiO_3$/NaOH of 1.5, LB ratio of 0.50, and using $75^{\circ}C$ curing temperature showed 7 days compressive strengths 22.0-81.0 MPa which are in the range of normal to high strength mortars.

• 대한약침학회지
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• 제17권1호
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• pp.13-19
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• 2014

Objectives: The present study investigated the protective effect of Wattakaka (W.) volubilis leaf extract against streptozotocin (STZ)-induced diabetes in rats. Methods: Male Wistar rats were divided into five groups (with six rats in each group) and were fed ad libitum. The rats were fasted for sixteen hours before diabetes was induced by injecting a single dose of 90 mg/kg body weight of STZ in 0.9-percent normal saline through an intraperitoneal route. The five groups were as follows: Group 1: normal control (saline-treated), Group 2: untreated diabetic rats, Groups 3 and 4: diabetic rats treated orally with petroleum ether cold maceration extract (PEME) of W. volubilis (50 and 100 mg/kg body weight), and Group 5: diabetic rats treated orally with metformin (250 mg/kg body weight). All rats received treatment for 21 days. For the STZ-induced diabetic rats, the blood-glucose, ${\alpha}$-amylase, total protein and alanine transaminase (ALT) levels were measured on days 7, 14 and 21 of the treatment with PEME of W. volubilis and the treatment with metformin. Histopathological changes in the liver were examined with hematoxylin-eosin staining. Morphological changes in the liver were also examined with glutaraldehyde fixation. Results: The treatments with PEME of W. volubilis and with metformin in experimental rats by oral injections for 21 days produced reductions in the levels of serum biochemical markers. Histopathology and scanning electron microscopy results showed that the administrations of PEME of W. volubilis and of metformin suppressed the generation of abnormal liver cells in the STZ-treated rats. Conclusion: These results suggest that both PEME of W. volubilis and metformin have a protective effect against STZ-induced diabetes.

• Journal of Ginseng Research
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• 제36권2호
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• pp.169-175
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• 2012

Ginseng has been used as a traditional medicine for treatment of many diseases and for general health maintenance in people of all ages. Ginseng is also used to ameliorate menopausal systems. We investigated the estrogenic activity of Korean red ginseng (KRG) in a transient transfection system, using estrogen receptor (ER) and estrogen-responsive luciferase plasmids in MCF-7 cells. The extract activated both ER${\alpha}$ and ER${\beta}$. KRG modulated the mRNA levels of estrogen-responsive genes such as pS2 and ESR1 and decreased the protein level of ER${\alpha}$. In order to examine in vivo estrogenic activity of KRG, sixteen female Sprague-Dawley rats separated into four groups were studied for nine weeks: non-ovariectomized (OVX) rats treated with olive oil, OVX rats treated with olive oil, OVX rats treated with 17-${\beta}$-estradiol (E2) in olive oil, and OVX rats treated with KRG extract in olive oil. The experiments were repeated for three times and the data of twelve rats were combined. Body weight of OVX rats was greater than that of sham-operated control rats and was decreased by E2 treatment. Uterine weight increased after E2 treatment compared to OVX rats. However, no difference in body or uterine weight was observed with KRG intake. KRG induced reductions in total cholesterol, low density lipoprotein cholesterol/total cholesterol, high density lipoprotein cholesterol/total cholesterol, and low density lipoprotein cholesterol/high density lipoprotein cholesterol, but not to the same degree as did E2 intake. These results show that KRG does contain estrogenic activity as manifested by in vitro study but the activity is not strong enough to elicit physiological responses.

• Nutrition Research and Practice
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• 제15권4호
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• pp.431-443
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• 2021

BACKGROUND/OBJECTIVES: Nobiletin (NOB), a citrus flavonoid, is reported to have beneficial effects on cardiovascular and metabolic health. However, there is limited research investigating the effect of long-term supplementation with low-dose NOB on high-cholesterol diet (HCD)-induced hypercholesterolemia and non-obese nonalcoholic fatty liver disease (NAFLD). Therefore, we investigated the influence of NOB on hypercholesterolemia and NAFLD in HCD-fed mice. SUBJECTS/METHODS: C57BL/6J mice were fed a normal diet (ND) or HCD (35 kcal% fat, 1.25% cholesterol, 0.5% cholic acid) with or without NOB (0.02%) for 20 weeks. RESULTS: HCD feeding markedly reduced the final body weight compared to ND feeding, with no apparent energy intake differences. NOB supplementation suppressed HCD-induced weight loss without altering energy intake. Moreover, NOB significantly decreased the total cholesterol (TC) levels and the low-density lipoprotein (LDL)/very-LDL-cholesterol to TC ratio, and increased the high-density lipoprotein-cholesterol/TC ratio in plasma, compared to those for HCD feeding alone. The plasma levels of inflammatory and atherosclerosis markers (C-reactive protein, oxidized LDL, interleukin [IL]-1β, IL-6, and plasminogen activator inhibitor-1) were significantly lower, whereas those of anti-atherogenic adiponectin and paraoxonase were higher in the NOB-supplemented group than in the HCD control group. Furthermore, NOB significantly decreased liver weight, hepatic cholesterol and triglyceride contents, and lipid droplet accumulation by inhibiting messenger RNA expression of hepatic genes and activity levels of cholesterol synthesis-, esterification-, and fatty acid synthesis-associated enzymes, concomitantly enhancing fatty acid oxidation-related gene expression and enzyme activities. Dietary NOB supplementation may protect against hypercholesterolemia and NAFLD via regulation of hepatic lipid metabolism in HCD-fed mice; these effects are associated with the amelioration of inflammation and reductions in the levels of atherosclerosis-associated cardiovascular markers. CONCLUSIONS: The present study suggests that NOB may serve as a potential therapeutic agent for the treatment of HCD-induced hypercholesterolemia and NAFLD.

• Nutrition Research and Practice
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• 제11권4호
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• pp.319-326
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• 2017

BACKGROUND/OBJECTIVE: Effective weight reduction remains a challenge throughout the world as the prevalence of obesity and its consequences are increasing. This study aimed to determine the effects of an individualized nutrition counseling program (IC) matched with a transtheoretical model (TTM) for overweight and obese subjects. SUBJECTS/METHODS: Fifty overweight and obese subjects aged 19-60 years with a body mass index ${\geq}23kg/m^2$ were enrolled in the weight reduction study. They were randomized into two groups: Intervention group received an IC matched with a TTM; control group received an educational handbook. Body weight (BW), body fat (BF), waist circumference (WC), waist to height ratio (WHtR), stages of change (SOC), processes of change (POC), food intake, and physical activity (PA) were assessed at baseline and at 4, 8, and 12 weeks after program initiation in both groups. All data were analyzed by intention-to-treat, using SPSS software for hypothesis testing. RESULTS: Forty-five female subjects were included in the 12-week trial at Ramkhamhaeng Hospital, Bangkok, Thailand. The results showed significant weight loss ($1.98{\pm}1.75kg$; 3% loss of initial weight) in the intervention group at 12 weeks, compared to a $0.17{\pm}1.67kg$ loss in the control group. There were significant differences between intervention and control groups in BF mass ($-1.68{\pm}1.78$, $-0.04{\pm}1.62kg$); percentage BF ($-1.54{\pm}2.11$, $0.08{\pm}2.05$); WC ($-5.35{\pm}3.84$, $0.13{\pm}3.23cm$); WHtR ($-0.0336{\pm}0.02$, $-0.0004{\pm}0.02$), and energy consumption ($-405.09{\pm}431.31$, $-74.92{\pm}499.54kcal/day$) in the intervention and control groups, respectively. Intragroup SOC was improved in both groups. The POC for the weight management action (WMA) process was significantly different with POC scores increasing by $16.00{\pm}11.73$ and $7.74{\pm}14.97$ in the intervention and the control groups, respectively. PA level did not change in either group. CONCLUSIONS: The IC matched with a TTM resulted in reductions in BW, BF, and WC, thus reducing likely health risks by decreasing energy intake and inducing positive behavior changes while enhancing the WMA process.

• International Journal of Naval Architecture and Ocean Engineering
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• 제2권1호
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• pp.45-56
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• 2010

Polymer composite materials offer high strength and stiffness to weight ratio, corrosion resistance, and total life cost reductions that appeal to the marine industry. The advantages of composite construction have led to their incorporation in U.S. yacht hull structures over 46 meters (150 feet) in length. In order to construct even larger hull structures, higher quality composites with lower cost production techniques need to be developed. In this study, the effect of composite hull fabrication processes on mechanical properties of glass fiber reinforced plastic (GFRP) composites is presented. Fabrication techniques investigated during this study are hand lay-up (HL), vacuum infusion (VI), and hybrid (HL+VI) processes. Mechanical property testing includes: tensile, compressive, and ignition loss sample analysis. Results demonstrate that the vacuum pressure implemented dining composite fabrication has an effect on mechanical properties. The VI processed GFRP yields improved mechanical properties in tension/compression strengths and tensile modulus. The hybrid GFRP composites, however, failed in a sequential manor, due to dissimilar failure modes in the HL and VI processed sides. Fractography analysis was conducted to validate the mechanical property testing results.

• 대한영양사협회학술지
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• 제11권1호
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• pp.125-132
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• 2005

Hypercholesterolemia has been regarded as a major risk factor of coronary heart disease(CHD). CHD is increasing in recent years among Koreans due to westernization of lifestyle and dietary behaviors. In the United States, implementation of the National Cholesterol Education Program(NCEP) had resulted 40% decline in mortality from CHD. This study was designed to evaluate the effect of medical nutrition therapy on serum lipid levels and discuss the effective nutrition education contents. Thirty outpatients(Male 40%, female 60%) with hypercholesterolemia were educated by medical nutrition therapy(MNT) protocol. At first visit and after three months of MNT, we assessed serum lipid profile, body weight and surveyed general characteristics, lifestyle and food habits through questionnaire. After 12 weeks of MNT, there were significant reductions in serum cholesterol and low-density lipoprotein cholesterol(LDL-C). Foods habits and lifestyle were changed to the desirable patterns. These results indicate that lipid profile is improved by changes of dietary behaviors and lifestyle. Especially in case of obesity, cholesterol lowering effect of MNT was more powerful. Consequently, MNT is effective on reduction of serum lipids by behavior change in hypercholesterolemic patients.

• 한국환경보건학회지
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• 제38권5호
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• pp.431-437
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• 2012

Objectives: This study aims to investigate the effects of voice disorders on changes in stress among people with damaged larynxes. To accomplish this, physiological changes and reductions in the stress of Sprague-Dawley rats whose larynx had been damaged were investigated after the laboratory animals were administered kudzu leaf extracts with sedative effects. Methods: In the experiment, a total of 24 rats were divided into four groups of six rats, including the normal group, control group, experimental group 1, and experimental group 2. After orally administering to the subjects a predetermined amount of the extract at a specific time (once per day over five weeks), changes in physiological functions, internal organ weight, cortisol, estrogen, and progesterone in the subjects were examined, and an immunological test was conducted on their brain tissues. Results: Statistical significance was seen in the experimental group as opposed to the control group and the results were similar to those of the normal group. Conclusions: In consideration of these results, it is deemed that there are severe effects on stress due to voice disorders and that the administration of kudzu leaf extracts results in improvement in stress.

• 콘크리트학회논문집
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• 제17권1호
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• pp.149-155
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• 2005

The purpose of this study is to investigate the flexural strengthening effects of CF(Carbon Fiber) sheet for the full-scale RC beams with multi-layer CF sheets. The partial strength reduction factors of CF sheets are suggested from the full-scale RC beams tests strengthened with multi-layer CF sheets up to six layers as well as material tests. From the material tensile tests, it was observed that the average tensile strengths of CF sheets per layer are decreased as the number of CF sheets is increased. Also the steep strength reductions of CF sheets in material test results at rupture are observed compared with the structural tests results for the full-scale RC beams strengthened with multi-layer CF sheets. Finally, the partial strength reduction factors far CF sheets up to six layers are suggested considering the effects of multi-layer and unit weight of CF sheets.

• KIEAE Journal
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• 제13권6호
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• pp.113-120
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• 2013

Many countries over the world have taken many discussions and endeavors on environmental improvements of energy savings and greenhouse gas emission reductions for solving global climate change problems. In Korea, pre-considerations of environment-conscious factors in buildings have been taken to be critical with new constructions and renovation markets. In this situation, the Korean Green Building Certification(KGBC) system to induce the diffusion of sustainable buildings was introduced in 2002 and developed as an improved version of the G-SEED(Green Standard for Energy and Environmental Design) system in 2013 after major revisions. This research examines the importance of assessment criteria on apartment buildings to certify green buildings using the AHP(Analytic Hierarchy Process) method and suggests a new direction on certification assessment standards from the AHP result. In order to apply the AHP method, the survey via e-mail was conducted to design staffs in domestic architectural firms. As a result, assessment criteria such as ecological environment, indoor environment, and energy & environment pollution among 7 main ones proved to be important on assessing the G-SEED system for apartment buildings, while criteria such as land use & transportation, material & resource, water circulation management, maintenance management did relatively unimportant.