Search

Addiction to Massive Multiple Online Role-Playing Games (MMORPGs) among juveniles has become a serious problem in Korea and has led to legislation prohibiting juveniles from playing games after midnight. One key factor in gaming addiction is the so-called narrative, or story, gamers create for themselves while playing. This study investigated how a course in writing and speaking using narrative characteristics and content borrowed from the MMORPG "Dungeon & Fighter (DF)" influenced language expression and gaming addiction. A total of 59 male high school students who were addicted to online gaming voluntarily participated in an experiment involving an educational course aimed at improving their writing and speaking. Participants were randomly divided into two groups, an experimental group of 27 students and a control group of 32 students (the control group participated in a general course addressing topics and various social issues unrelated to gaming). The experiment consisted of a total of 21 sessions lasting 2 h per day over a period of 2 months. The results of a follow-up examination revealed that participants in the experimental group improved their writing and speaking ability far more than those in the control group. In addition, a pilot ERP study suggested that the educational course in the experiment may reflect how gaming activity is processed in the brain, especially in the fronto-central areas, and thereby influence the course of addiction. (Contains 6 figures and 7 tables.)

Abalone production in Korea has reached 5000 metric tonnes (MT) since 2000 and has been consistently increasing to reach 10,000 MT in 2015. Abalone fisheries are mainly seen in Wando on the south coast of Korea, where seaweed aquaculture has been majorly conducted. Mass mortality of abalone spats is considered a major problem in abalone fisheries and is caused by changes in environmental factors and food availability (including availability of benthic diatoms). However, it is difficult to supply sufficient quantities of benthic diatoms to post-larvae abalone. Therefore, we explored the development of growth-promoting substances for diatoms Navicula sp. and experimentally mixed several substances to enhance the growth of diatoms. In this study, we used alginic acid, fucoidan, Scytosiphon lomentaria, Ecklonia cava, Ecklonia cava processing byproduct (i.e., Ecklonia cava–boiled extracts, EBE), and Porphyra tenera. In addition, EBE, phosphate fertilizer (PF), nitrogenous manure (NM), and sodium silicate (SS) were mixed to determine the optimal composition of growth substances. The growth of diatoms significantly increased under EBE exposure, compared with other substances. During this study, attempts were made to identify the optimal composition of mixtures of PF, NM, and SS with that of EBE (1:1:1:1). The Navicula sp. growth-promoting substance (NGPS) mixture enhanced Navicula sp. growth by 150% compared with existing market products. We were therefore able to develop a substance that promotes the growth of diatoms, thereby facilitating the cultivation of healthy abalone with reduced mortality. [ABSTRACT FROM AUTHOR]

This study aims to determine the characteristics of hydrological behaviors in the basins of the representative multipurpose dams in the Korean Peninsula that depend on typhoon conditions for sustainable water management and restoration of the water ecosystem. Based on the annual maximum flow and seven-day low-flow results, trend analyses were conducted on hydrological changes, such as magnitude, timing, duration, and frequency of the extreme flows. Among the eight selected multipurpose dams in South Korea, the Chungju and Soyang dams have been subject to dramatic reduction of inflow during the spring and early summer. The Sumjin Dam was indicated the most sensitive to the severity and magnitude of typhoons and it showed a statistically significant increase in the frequency and duration of peak inflows resulting from such typhoons. As regards low flow, the Chungju and Andong dams showed a distinct reduction in this flow in the winter, but the changes resulting from typhoons were relatively subtle. This diagnostic study is expected to provide foundational data to examine the causalities related to the streamflow patterns of Korean basins. In addition, the study could aid in establishing basin-customized mid- and long-term measures for supplying of water resources in the environmental system and for managing the effects of natural disasters by analyzing various hydrological changes related to extreme events. [ABSTRACT FROM AUTHOR]

Seahorses, Hippocampus abdominalis, have a long history in traditional Chinese medicine as an important healthy ingredient in foods. This study evaluated the antioxidant activity of an enzymatic hydrolysate prepared from a seahorse bred in Jeju, South Korea. Experiments were performed in vitro using electron spin resonance spectrometry (ESR) to determine the free radical scavenging activity and in vivo using a zebrafish model to determine the protective effects against 2,2‐azobis hydrochloride (AAPH)‐induced oxidative damage. H. abdominalis protein hydrolysate (HPH) exhibited peroxyl radical scavenging activity (IC50 = 0.58 mg/ml) generated by the water‐soluble AAPH (azo initiator of peroxyl radicals). HPH reduced dose‐dependently both intracellular reactive oxygen species (ROS) levels in AAPH‐induced cells and cell death in AAPH‐induced zebrafish embryos. The antioxidant peptide purified from HPH was identified as a tripeptide (alanine–glycine–aspartic acid) using Q‐TOF ESI mass spectroscopy. Thus, this study demonstrated that HPH contains antioxidant peptides that exhibit a strong antioxidant activity. Practical applications: Hippocampus abdominalis is one of the largest seahorse species and cultivated in many countries. Because of its large body size compared to other seahorse species, H. abdominalis has acquired considerable consumer attraction in the global market. Owing to its biologically useful properties, it recently gained attention as the natural products obtained from H. abdominalis have varied applications in the field of medicine, health care products, and functional foods. Thus, commercial products of this particular seahorse species are popular among customers, especially in China. The purpose of this study was to evaluate the antioxidant property of H. abdominalism, cultured in a commercial seahorse farm in Jeju Island. Owing to its prominent antioxidant activity, it could be used as an ingredient in medicinal preparations, nutraceuticals, and functional foods. [ABSTRACT FROM AUTHOR]

Sargassum horneri is a nutrient rich edible brown seaweed with numerous biological properties found in shallow coastal areas of Korean peninsula. S. horneri traditionally used as a medicinal ingredient to treat several disease conditions such as hyperlipidemia, hypertension, heart disease, and inflammatory diseases (furuncle). However, to utilize S. horneri as an active ingredient for functional foods and human health applications requires to conform the bioactive properties and underlying mechanisms of those activities. Aim of the study: Here, we investigated anti-inflammatory mechanisms of commercial grade 70% ethanol extract separated from S. horneri (SHE) on inflammatory response in particulate matter (PM)-induced MH-S lung macrophages; where PM in breathable air one of the major health concern in Korea. We compared the anti-inflammatory effects of SHE on the activity of toll-like receptors (TLR) activation, NF-κB, MAPKs, and pro-inflammatory cytokine secretion in MH-S lung macrophages exposed to PM as a lung inflammation model. According to the results, PM-stimulation, induced the levels of NO, PGE2, TNF-α, IL-1β, IL-6, iNOS, and COX2 (P < 0.05) in MH-S macrophages. In addition, phosphorylation levels of NF-κB and MAPKs were also increased with the PM stimulation through the upregulated expression of TLR. However, SHE treatment significantly repressed the secretions of inflammatory cytokines and reduced protein expression such as PGE2, TNF-α, IL-6, IL-1β, NF-κB, and MAPKs from PM-activated macrophages. Specifically, SHE inhibited the upregulated mRNA expression levels of TLR2, TLR3, TLR4, and TLR7 in PM-induced MH-S cells; known biomarkers of downstream activation of NF-κB and MAPKs. These results suggested that SHE is a potential inhibitor of PM-induced inflammatory responses in lung macrophages. Thus, SHE could inhibit PM-induced chronic inflammation in lungs via blocking TLR/NF-κB/MAPKs signal transduction. Therefore, it was concluded that SHE may be a useful substance to develop as functional product to reduce inflammation against PM-induced inflammation. Image 1 [ABSTRACT FROM AUTHOR]

Obesity is known as metabolic syndrome and it affects many tissues including adipose tissue, liver, and central nervous system (CVS). Gambi-jung (GBJ) is a modified prescription of Taeumjowi-tang (TJT), which has been used to treat obesity in Korea. GBJ is composed of 90% Ephedra sinica Stapf (ES). Therefore, the present study was designed to assess the antiobesity effects of GBJ and to compare the effects of GBJ and ES on obesity. GBJ administration remarkably reduced the body weight, Body mass index (BMI), and body fat percentage compared to the ES administration in human subjects. GBJ-treated mice had lower white adipose tissue (WAT) amounts than ES-treated mice. GBJ and ES administration enhanced adenosine monophosphate-activated protein kinase (AMPK) expression in 3T3-L1 adipocytes, epididymal WAT and liver of HFD-induced obese mice. Moreover, GBJ and ES reduced food intake by suppressing the mRNA levels of orexigenic peptides, agouti-related protein (AgRP) and neuropeptide-Y (NPY), as well as AMPK in the brain of HFD-induced obese mice. Furthermore, GBJ-treated mice had dramatically lower expression of macrophage marker F4/80 in epididymal WAT than those of ES-treated mice. Based on these results, we suggest the use of GBJ as a natural drug to control weight gain. [Display omitted] • GBJ revealed anti-obesity effects via regulation of AMPK expression in vitro and in vivo model. • GBJ induced weight loss in overweight/obese human subjects. • Both GBJ and ES strongly reduced body weight gain. • Meanwhile, GBJ administration had higher suppressive effects on WAT expansion than ES administration. [ABSTRACT FROM AUTHOR]