• Journal of agriculture & life science
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• v.53 no.2
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• pp.121-129
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• 2019

This study carried out to determine control factors for the improvement of productivity of laying hens suffering heat stress during hot weather. A total of 48,451 ISA Brown layers were housed in a farm located in Gyeongsangnam-do, Republic of Korea. Five thermo-hydrometer loggers were installed inside the house to collect data of dry-bulb temperature and relative humidity. The experiment continued for 81 days when the summer season begins from 19th June to 7th September, 2018. This study analyzed the correlations among layers' production index and daily average, highest, and lowest temperature; daily average, highest, and lowest relative humidity; and daily average, minimum, and maximum THI. The result indicated that feed consumption, hen-day egg production, egg weight, and FCR decreased as the daily average, highest and lowest dry-bulb temperature and THI rise (p<0.01). On the other hand, water intake increased as the daily average, highest and lowest dry-bulb temperature and THI rise (p<0.001). The relative humidity was not considered to have direct correlations to the layers' production index (p>0.05). However, it was noticeable that the mortality did not have significant relations with daily average and highest temperature; THI; or daily average, highest and lowest relative humidity while it was relevant to the daily lowest temperature and THI (p<0.05). In conclusion, to enhance the productivity of laying hens in a hot climate, it is recommended that daily average, highest, and lowest dry-bulb temperature and THI are maintained as low as possible. Especially, the daily lowest temperature is needed to lower to 20℃, which is the lowest critical temperature for layers.

• The Journal of Internal Korean Medicine
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• v.29 no.4
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• pp.988-999
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• 2008

Objectives : The study was conducted to evaluate antioxidative, anti-atherosclerotic and anti-hypertensive effects of natural remedies. Alisma Rhizome (AR) has been used for a long time in Asia in folk remedies for treatment of hypertension and stroke and has been used in Korean traditional medicine for the treatment of glycosuria, gonorrhea, hypercholesterolemia, hypertension, and jaundice and its diuretic effect. These pharmacological effects of AR might come from antioxidant properties of phytochemicals in these materials. Methods : In this study, the antioxidant activity of extract from AR was studied with in vitro methods by measuring the antioxidant activity by TEAC, measuring the scavenging effects on reactive oxygen species (ROS) [superoxide anion, hydroxyl radical] and on reactive nitrogen species (RNS) [nitric oxide and peroxynitrite] as well as measuring the inhibitory effect on $Cu^{2+}$ induced human LDL oxidation and on ACE. Results : The AR extracts were found to have a potent scavenging activity, as well as an inhibitory effect on LDL oxidation and on ACE against all of the reactive species tested, with the water extract showing particularly strong antioxidant activities. Conculsions : The AR extracts have antioxidative, anti-atherosclerotic and anti-hypertensive effects in an in vitro system, which can be used for developing pharmaceutical drugs against oxidative stress and atherosclerosis.

• Journal of Yeungnam Medical Science
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• v.26 no.2
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• pp.102-107
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• 2009

Background : Constipation is one of the most common disorders in Korea and Western countries. It may be related with life style, diet, physical activity, age, stress and gender, and particularly premenopausal women experience constipation more often than men due to the significant prolongation of the mean colonic transit in women. The aim of this study was to evaluate the effect of a probiotic on constipation in loperamide-induced constipated rats. Materials and Methods : The rats were divided into 3 groups. Constipation was induced by administration of loperamide for 5 days, and the excreted amount as well as the number of feces was observed. Lactic acid bacteria as a probiotic were administered orally every day for 5 days. Results : The results showed that loperamide administration induced severe experimental constipation in rats. The amount of feces was decreased and the number of pellets was increased by loperamide. The water content in the feces as a parameter of constipation was also decreased by loperamide. On the other hand, the dry weights of feces were not significantly different among the groups. It represents that the amount of food consumption might have been similar among the groups, and constipation was caused by delayed intestinal movement. Conclusion : Probiotic administration for 5 days in rats partly alleviated or prevented the constipation induced by loperamide.

• The Korea Journal of Herbology
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• v.29 no.6
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• pp.63-71
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• 2014

Objectives : Lonicerae japonicae Flos(LJF) has been reported to exhibit anti-oxidant, anti-inflammatory, anti-viral, anti-rheumatoid properties. However, it is still largely unknown whether LJF inhibits the ultraviolet(UV)B-induced oxidative damage in human HaCaT keratinocytes. Therefore in this paper, we investigated the anti-oxidative capacity and protective effect of LJF against UVB-induced oxidative demage in human HaCaT keratinocytes. Methods : To evaluate the anti-oxidative activity of LJF extracts, we measured total phenolic contents, total flavonoid contents, antioxidant capacity, and superoxide scavenging activity. To give an oxidative stress to HaCaT cells, UVB was irradiated with $200mJ/cm^2$ to HaCaT cells. To detect the protective effect of LJF against UVB, we measured cell viability, DNA fragmentation and reactive oxygen species (ROS) production. In addition, we performed high-performance liquid chromatography (HPLC) analysis to find a major component of LJF. Results : LJF contained phenolic and flavonoid contents, and showed the anti-oxidant and superoxide scavenging activity. The UVB-induced oxidative conditions led to the cell death, DNA fragmentation and reactive oxygen species (ROS) production. However, pretreatment with LJF reduced oxidative conditions, including inhibition of cell death, DNA fragmentation and ROS production. In addition, we found out chlorogenic acid as major component of LJF. Conclusions : These results could suggest that LJF contained anti-oxidative contents and exhibited protective effects against UVB on human HaCaT keratinocytes. And the effective compound of LJF which could show protective activities against UVB is chlorogenic acid. Thus, LJF and chlorogenic acid would be useful for the development of drug or cosmetics treating skin troubles.

• Journal of the Korea Concrete Institute
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• v.25 no.4
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• pp.401-409
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• 2013

In the present study, numerical analysis was performed for hydrodynamic motion and structural performance on four different concrete floating structures, which have same cross-section but different length. The hydrodynamic analysis of floating structures is carried out using ANSYS AQWA with the different 34 wave load on regular wave period from three seconds to ten seconds in 35 m water depth. In order to evaluate structural performance of floating structures under the critical wave load which obtained from hydrodynamic analysis. The integrated analysis is also carried out through the mapping method, which can directly connect the wave-induced hydraulic pressure obtained form ANSYS AQWA to Finite Element Model in ANSYS Mechanical. As a results of this study, the hydrodynamic motion of floating structures is decreased as the length of structure increased. It means that the effect of wave-structure interaction is strongly dependent on the relationship between a wave period and a length of structure. Moreover, it is found that tension stress on bottom slab of floating structure is occurred by the critical wave load, the sectional force is not influenced by length of a structure.

• Journal of the Korean Wood Science and Technology
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• v.39 no.4
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• pp.344-350
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• 2011

In this study, LVLs of radiata pine were fabricated with non-preservative treated veneers, CuAz treated veneers, and ACQ treated veneers, using aqueous vinyl urethane adhesive and phenol modified resorcinol resin adhesive. Then density gradient, bonding strength, bending properties and decay resistance of LVLs were evaluated. As results, the cone-shaped and higher density gradient pattern was found in layer close to glueline. After cyclic water boiled test, the LVL bonded with aqueous vinyl urethane resin adhesive was delaminated in all layers or partly delaminated including check, chasm in glueline layer. In the case of LVL bonded with phenol modified resorcinol resin adhesive, despite slight cupping due to great glueline stress and vertical check between glueline layers, it was observed that the bonding strength to delamination was higher, owing to most absence of delamination through overall glueline. On the other hand, in the decay test, mass loss by brown rot fungi was greater than white rot fungi in LVL bonded with aqueous vinyl urethane resin adhesive. However, in LVL bonded with phenol modified resorcinol resin adhesive, the mass loss by brown rot fungi was slight and non-preservative treated LVL was low. The mass loss of preservative-treated LVL was 0 (zero), showing the high decay resistance effect.

• Journal of the Korean Geotechnical Society
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• v.36 no.11
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• pp.71-81
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• 2020

The large circular steel pipe for a marine bridge foundation has been developed as a construction method capable of performing the role of the working platform and cofferdam. The objective of this study is to demonstrate the wireless remote sensing system for monitoring the stability of the large circular steel pipe during construction and operation through field tests. The artificial seabed ground with an water level of 4 m is constructed for field tests. The large circular steel pipe with a diameter of 5 m and height of 9.5 m is installed into the ground by suction, and the embedded depth is 5 m. The inclinometer and strain gauges are installed on different surfaces of the upper module, and the tilt angle and stress are monitored throughout the entire construction process. As results, tilt angles are measured to be constant during the suction penetration. However, the tilt angle is larger in the x-axis direction. In addition, even when installed on different surfaces, the tilt angle in the same axial direction is measured to be almost the same. The stresses measured by strain gauges increase during suction penetration and decrease during pull-out. Based on measured stresses, it is found that the eccentricity is acting on the large circular steel pipe. This study shows that a wireless remote sensing system built with an inclinometer and strain gauge can be a useful tool for the stability monitoring of the large circular steel pipe.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.1
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• pp.64-69
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• 2004

The deficiency of the neurotransmitter acetylcholine(ACh) is responsible for the initiation of Alzheimer's disease. In addition, there is a simple evidence that oxidative stress significantly increases in persons with Parkinson's disease compared to age-matched healthy persons. Therefore, the objective of the study was to investigate the neurodegeneration inhibitory effect of soybean(Glycine Max) and Yak-Kong(Rhynchosia Nolubilis) by measuring the degree of inhibiting Acetylcholinesterase (AChE) catabolizing the ACh and the free radical scavenger effect in vitro. AChE was measured by the minor modified Ellman assay. Free radical scavenging activity was measured using l-diphenyl-2-picrylhydrazyl (DPPH). First, the MeOH extracts of Soybean and Yak-Kong showed the AChE inhibiting activity of 62.0$\pm$2.43％ and 65.0$\pm$3.29％ at the 5 mg/$m\ell$ concentration. The 50％ inhibitory concentration ($IC_{50}$/) of AChE was 1.96 and 1.31 mg/$m\ell$ in the MeOH extracts of soybean and Yak-Kong. Second, the MeOH extracts of soybean and Yak-Kong showed the free radical scavenger activity of 23.1$\pm$4.26％ and 80.7$\pm$4.61％ at the 5 mg/$m\ell$. IC50 of free radical scavenger activity in Soybean and Yak-Kong was 13.00 and 1.41 mg/$m\ell$ in MeOH extracts and was 5.95 and 2.74 mg/$m\ell$ in hot-water extracts, respectively. In this study, the extracts of Soybean and Yak-Kong showed powerful effects in the AChE inhibition and free radical scavenging. The extracts of Soybean and Yak-Kong were expected to prevent the many neurodegenerative diseases.

• Journal of Nutrition and Health
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• v.53 no.3
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• pp.255-270
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• 2020

Purpose: The purpose of this study was to identify the factors that influence the consumption of convenience foods among Korean adolescents. Methods: This study had a descriptive cross-sectional study. Data were obtained from the 15th (2019) Korea Youth Risk Behavior Web-based Survey, which involved a nationwide representative sample of 57,303 middle- and high-school students. Convenience-food consumption was defined by frequency of adolescents consuming convenience foods obtained from convenience stores, supermarkets, and cafeterias over the previous 7 days. The analyzed variables were related to sociodemographic, mental health, and health behavior. The Rao-Scott χ² test was applied to examine the difference in the rate of consuming convenience foods obtained from convenience stores according to each factor. Hierarchical logistic regression was conducted to examine the factors that influence convenience-food consumption among Korean adolescents. Results: It was found that 29.1% of Korean adolescents consumed convenience foods obtained from convenience store more than three times per week. The significant influencing factors were female sex; low subjective academic achievement, and subjective household economic status; high perceived stress; low subjective sleep sufficiency; experience of depression; suicidal ideation; lower physical activity; skipping breakfast; lower consumptions of fruit, milk, and vegetables; higher consumptions of soda drinks, sweet drinks, caffeine, and fast food; lower water intake; current smoking and drinking; drug use; and experience of violence. Conclusion: These findings provide a better understanding of the sociodemographic, mental-health, and health-behavior factors that influence the consumption of convenience foods among Korean adolescents. We suggest that differentiated policies, strategies, and nutrition education need to be developed and implemented, in order to address the above-mentioned factors and thereby reduce such behaviors among Korean adolescents.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.3
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• pp.139-146
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• 2017

In order to understand the efficacy of submerged breakwater constructed for the beach protection, laboratory experiments were carried out by observing the characteristics of flow around a single shore-parallel submerged breakwater. The velocity field near the shoreline was measured by utilizing the LSPIV (Large-Scale Particle Image Velocimetry) technique, and mean surface and wave height distributions were observed around the submerged breakwater, according to various combinations of incident waves and submerged breakwaters. In this experiment, it was found that the mean flow pattern behind the submerged breakwater was determined by the balance among the gradients of mean water surface and excess wave-momentum flux (i.e., radiation stress tensors) which interact with the wave-induced current developed by the gradients on the rear and the side of the submerged breakwater. The divergent and convergent flow patterns behind the submerged breakwater (i.e., accretion and erosion response) of the numerical study of Ranasinghe et al.(2010) were observed in the measured velocity distributions, and their empirical formula mostly agreed with the experimental results. However, for some cases in this experiment, it was difficult to say that the flow pattern was one of them and was agreed with the empirical formula.