• Journal of the Korean Society of Food Culture
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• v.21 no.1
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• pp.71-75
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• 2006

This study was conducted to investigate the eliminatory effect of health drink containing Hovenia dulcis Thunb extract on ethanol-induced hangover in rats. Male Sprague-Dawley rats weighing $200{\pm}10\;g$ were given health drink (10 mL/kg) or other company product(10 mL/kg) 30 min before or after 40% ethanol (5 g/kg body weight) ingestion. To study the effect of health drink on blood ethanol concentration, blood was taken from caudal artery at 1, 3, 5 hr and the animal were sacrificed 24 hr after ethanol ingestion. From 1 to 5 hr, health drink pre- or postdosing significantly decreased the ethanol levels in the blood. The acetaldehyde concentration showed decrement in health drink group and other company product group. The activities of ethanol, alcohol dehydrogenase and aldehyde dehydrogenase measured at postdosing, were also not altered by the administration of health drink. Alanine aminotransferase and aspartate aminotransferase activities showed unaltered resulted in all experimental groups compared with the normal group. These results suggest that oral intake of health drink containing Hovenia dulcis Thunb is effective on elimination of ethanol-induced hangover.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3A
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• pp.201-209
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• 2010

Generally, PSC girder bridge uses total gross cross section to resist applied loads unlike reinforced concrete member. Also, it is used as short and middle span (less than 30 m) bridges due to advantages such as ease of design and construction, reduction of cost, and convenience of maintenance. But, due to recent increased public interests for environmental friendly and appearance appealing bridges all over the world, the demands for longer span bridges have been continuously increasing. This trend is shown not only in ordinary long span bridge types such as cable supported bridges but also in PSC girder bridges. In order to meet the increasing demands for new type of long span bridges, PSC hollow box girder with H-type steel as compression reinforcements is developed for bridge with a single span of more than 50 m. The developed PSC girder applies compressive prestressing at H-type compression reinforcements using unbonded PS tendon. The purpose of compressive prestressing is to recover plastic displacement of PSC girder after long term service by releasing the prestressing. The static test composed of 4 different stages in 3-point bending test is performed to verify safety of the bridge. First stage loading is applied until tensile cracks form. Then in second stage, the load is removed and the girder is unloaded. In third stage, after removal of loading, recovery of remaining plastic deformation is verified as the compressive prestressing is removed at H-type reinforcements. Then, in fourth stage, loading is continued until the girder fails. The experimental results showed that the first crack occurs at 1,615 kN with a corresponding displacement of 187.0 mm. The introduction of the additional compressive stress in the lower part of the girder from the removal of unbonded compressive prestressing of the H-type steel showed a capacity improvement of about 60% (7.7 mm) recovery of the residual deformation (18.7 mm) that occurred from load increase. By using prestressed H-type steel as compression reinforcements in the upper part of cross section, repair and rehabilitation of PSC girders are relatively easy, and the cost of maintenance is expected to decrease.

• Journal of the Korean Society of Food Culture
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• v.24 no.1
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• pp.77-83
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• 2009

This study was conducted to investigate the chemical composition and biological function of tea made from mountain-cultivated ginseng leaves. The antioxidant activities of tea made from mountain-cultivated ginseng leaves were determined by measuring their electron-donating ability based on their DPPH and nitrite-scavenging ability. The electron-donating abilities of tea made from mountain-cultivated ginseng leaves (500 and 1,000 ppm) as determined by DPPH assay were 45.6 and 85.1%, respectively. The nitrite scavenging ability of tea made from mountain-cultivated ginseng leaves (500 and 1,000 ppm) at pH 6.0 were 32.8 and 51.4%, respectively. Furthermore, the nitrite scavenging activity increased in a dose-dependent manner at all pH values. The effects of tea made from mountain-cultivated ginseng leaves on Male Sprague-Dawley rats were also evaluated. To accomplish this, the rats were divided into three groups (A: normal diet group, B: high fat diet group and C: high fat diet supplemented with tea made from mountain-cultivated ginseng leaves group). The anti-obesity effects of tea made from mountain-cultivated ginseng leaves were then evaluated. The serum total lipid, total cholesterol and triglyceride contents in C group were lower than those of B group; however, these differences were not statistically significant. The HDL-cholesterol content was significantly higher in the C group than in the other groups. Taken together the results of this study suggest that tea made from mountain-cultivated ginseng leaves possesses antioxidant activity and improves lipid metabolism.

• Journal of Nutrition and Health
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• v.56 no.3
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• pp.315-329
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• 2023

Purpose: This study examined the meal-kit consumption practices of adults in their 20s and 30s and analyzed the properties that should be given priority for improvement among the selection attributes to improve the quality of meal-kits. Methods: Statistical analyses were conducted using the SPSS program (ver. 28.0) for χ²-test, t-test, one-way analysis of variance, Duncan's multiple range test, factor analysis, and Importance-Satisfaction Analysis (ISA). Results: Of the 249 subjects surveyed, 85.5% had some experience of purchasing meal-kits, with significantly more females than males (p < 0.01), significantly more married people than single people (p < 0.05), significantly more employed people than unemployed people (p < 0.05). Meal-kits were purchased most frequently for meals (60.6%), from discount stores or supermarkets (44.6%), and priced between 10,000 won and 20,000 won per person (46.9%). The overall satisfaction with meal-kits was 4.1 out of 5.0 points. The frequency of purchases was Korean soup dishes (69.5%), Korean main dishes (47.4%), and Korean street snacks (46.9%). Factor analysis of the meal-kit selection attributes revealed, 4 factors: 'quality of food,' 'packaging and diversity,' 'quality of meal-kit,' and 'convenience and price.' Compared to single-person households, multi-person households placed significantly higher importance on the 'quality of food,' 'packaging and diversity,' and 'quality of meal-kit.' The factor, 'packaging and diversity' were significantly higher in the importance evaluation scores for females (p < 0.01), married people (p < 0.05), and people in their 30s (p < 0.05) among meal-kit consumers. According to the ISA results, a critical aspect that meal-kit manufacturers or sellers should strengthen is 'price.' Conclusion: Meal-kit products will need to be developed for various purposes that offer high value for money that can satisfy the consumers' needs to improve the satisfaction of meal-kit consumers.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.131-139
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• 2023

In this study, we investigated pesticide residue levels in 535 domestically distributed agricultural products in South Korea using multi-residue analysis. Agricultural products from 13 regions, including Seoul, were pretreated using QuEChERS and d-SPE, and subsequently analyzed using LC-MS/MS and GC-MS/MS. Residual pesticides were detected in 288 (53.8%) out of the 535 samples, including 40 of apples, 40 of peppers, 33 of mandarins, 31 of peaches, and 144 other commodities. Furthermore, one sample of Korean cabbage exceeded the permitted maximum residue limit (MRL), diniconazole (0.18 mg/kg), detected at about twice the MRL. In total, 91 types of residual pesticides were detected, including fungicides (42), insecticides (48), and a nematicide. The most frequently detected pesticides were dinotefuran (91), carbendazim (75), tebuconazole (61), and pyraclostrobin (59). Our results showed that continuous monitoring of agricultural products is necessary.

• Journal of the Korean Society of Food Culture
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• v.23 no.2
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• pp.222-227
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• 2008

This study examined the chemical composition of lotus root and functionally evaluated a fermented lotus root drink. Electron-donating ability using DPPH along with nitrite-scavenging ability were used to compare the antioxidative activities of unfermented and fermented lotus root drinks. The electron-donating abilities of the unfermented lotus root drink (1%) and fermented lotusroot drink (1%) were 22.55% and 23.88%, respectively. At pH 6.0, the nitrite-scavenging abilities of the unfermented lotus root drink and the fermented lotus root drink (100%) were 27.64% and 40.3%, respectively, and their scavenging ability increased in a dose-dependent manner at all pH values. In order to study the anti-obesity effects of the two drinks, male Sprague-Dawley rats were divided into four groups (A: basal diet, B: high fat diet, C: high fat diet+unfermented lotus root drink, D: high fat diet+fermented lotus root drink). Net weight gains were not significantly different among the four groups. Plasma total cholesterol concentrations significantly decreased in the groups receiving the unfermented and fermented lotus root drinks. Also, plasma total lipid and triglyceride contents were lower in the groups receiving the unfermented and fermented lotus root drinks as compared to the high fat diet group; however, the differences among the three groups were not significant.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5A
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• pp.407-415
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• 2010

In Korea, more than 90% of the total number of steel bridges built for 40~70 m span length is a steel box-girder bridge type. A steel box-girder bridge is suitable for long span or curved bridges with outstanding flexural and torsional rigidity as well as good constructability and safety. However, a steel box-girder bridge is uneconomical, requiring many secondary members and workmanship such as stiffeners and ribs requiring welding attachments to flanges or webs. Therefore, in US and Japan, a plate girder bridge, which is relatively cheap and easy to construct is generally used. One type of the plate girder bridge is the two- or three-main girder plate bridge, which is a composite plate girder bridge that minimizes the number of required main girders by increasing the distance between the adjacent girders. Also, for the simplification of girder section, the stiffener which requires attachment to the web is not required. The two-main steel girder plate bridge is a representative type of plate girder bridges, which is suitable for bridges with 10 m effective width and has been developed in the early 1960s in France. To ensure greater safety of two- or three-main girder plate bridges, a larger steel section is used in the bridge domestically than in Europe or Japan. Also, the total number of two- or three-main girder plate bridge constructed in Korea is significantly less than the steel box girder bridge due to a lack of designers' familiarity with more complex design detailing of the bridge compare to that of a steel box girder bridge design. In this study, a new construction method called Turn Over method is proposed to minimize the steel section size used in a two- or three-main girder plate bridge by applying prestressing force to the member using confining concrete section's weight to reduce construction cost. Also, a full scale 20 m Turn Over girder specimen and a Turn Over girder bridge specimen were tested to evaluate constructability and structural safety of the members constructed using Turn Over process.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.565-575
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• 2009

In recent years, there have been numerous explosion-related accidents due to military and terrorist activities. Such incidents caused not only damages to structures but also human casualties, especially in urban areas. To protect structures and save human lives against explosion accidents, better understanding of the explosion effect on structures is needed. In an explosion, the blast load is applied to concrete structures as an impulsive load of extremely short duration with very high pressure and heat. Generally, concrete is known to have a relatively high blast resistance compared to other construction materials. However, normal strength concrete structures require higher strength to improve their resistance against impact and blast loads. Therefore, a new material with high-energy absorption capacity and high resistance to damage is needed for blast resistance design. Recently, Ultra High Strength Concrete(UHSC) and Reactive Powder Concrete(RPC) have been actively developed to significantly improve concrete strength. UHSC and RPC, can improve concrete strength, reduce member size and weight, and improve workability. High strength concrete are used to improve earthquake resistance and increase height and bridge span. Also, UHSC and RPC, can be implemented for blast resistance design of infrastructure susceptible to terror or impact such as 9.11 terror attack. Therefore, in this study, the blast tests are performed to investigate the behavior of UHSC and RPC slabs under blast loading. Blast wave characteristics including incident and reflected pressures as well as maximum and residual displacements and strains in steel and concrete surface are measured. Also, blast damages and failure modes were recorded for each specimen. From these tests, UHSC and RPC have shown to better blast explosions resistance compare to normal strength concrete.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.557-564
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• 2009

In recent years, there have been numerous explosion-related accidents due to military and terrorist activities. Such incidents caused not only damages to structures but also human casualties, especially in urban areas. To protect structures and save human lives against explosion accidents, better understanding of the explosion effect on structures is needed. In an explosion, the blast overpressure is applied to concrete structures as an impulsive load of extremely short duration with very high pressure and heat. Generally, concrete is known to have a relatively high blast resistance compared to other construction materials. However, information and test results related to the blast experiment of internal and external have been limited due to military and national security reasons. Therefore, in this paper, to evaluate blast effect on reinforced have concrete structure and its protective performance, blast tests are carried out with $1.0m{\times}1.0m{\times}150mm$ reinforce concrete slab structure at the Agency for Defence Development. The standoff blast distance is 1.5 m and the preliminary tests consists with TNT 9 lbs and TNT 35 lbs and the main tests used ANFO 35 lbs. It is the first ever blast experiment for nonmilitary purposes domestically. In this paper, based on the basic experiment procedure and measurement details for acquiring structural behavior data, the blast experimental measurement system and procedure are established details. The procedure of blast experiments are based on the established measurement system which consists of sensor, signal conditioner, DAQ system, software. It can be used as basic research references for related research areas, which include protective design and effective behavior measurements of structure under blast loading.

• Korean Journal of Psychosomatic Medicine
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• v.31 no.1
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• pp.25-32
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• 2023

Objectives : This study investigated the level of sexuality knowledge and gender sensitivity and factors influencing on them among Korean high school and college students. Methods : 129 questionnaires from high school and college students with consent forms, collected from July to December of 2022, were analyzed. After identification of participants' gender, age, major, their report of the practicality of sex education, and their experience of violence or sexual assaults, participants' level of sexuality knowledge and gender sensitivity were compared. Results : Females showed higher gender sensitivity, regardless of age and group (p=0.004). The early adulthood group (≥19 years old) showed higher sexuality knowledge and gender sensitivity, compared to those adolescents (<19 years old). Among college students, those who majored in health science were identified with higher sexuality knowledge and gender sensitivity, compared to non-health science major students(p<0.001; p=0.005). Conclusions : This study revealed the significant differences in sexuality knowledge and gender sensitivity according to sex, age, and majors in adolescents and early adults. Therefore, it seems to be necessary to consider the differences in sexuality knowledge and gender sensitivity among age, sex, and majors when establishing public policy or legislation for sex crimes, including digital sex crimes.