• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.3
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• pp.115-123
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• 2010

The occurrence and variation of oxygen deficient water mass (ODW) in Namdae stream estuary, Yangyang were studied. Field observations for water properties and sediment environments were conducted at 5 stations of the estuary from April 2008 to November 2008. The coastal sandbar is developed at the estuary mouth, and there is a pool between the estuary mouth and about 2.3 km upstream of the estuary. The pool is relatively deep and narrow compared to riverbed of the estuary. The ODW was observed continuously in the pool from May to October. The ODW extends vertically up to 2 m depth in August, and maximum length of the ODW were about 2.3 km. Mean concentration of ignition loss (IL) and acid volatile sulfide (AVS) of sediment was 7.5~9.0%, $0.282{\sim}1.106\;mg/g{\cdot}dry$ wt, respectively. Ammonium concentration in the bottom layer during formation period of the halocline and the ODW was 4~23 times higher than that of surface layer. ODW was initiated by the introduction of seawater into bottom of the estuary pool to make a strong halocline, and then decomposition of organic matter within sediment accelerated the formation of the ODW.

• Economic and Environmental Geology
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• v.47 no.4
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• pp.317-333
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• 2014

The Pocheon iron (-copper) deposit, located at the northwestern part of the Precambrian Gyeonggi massif in South Korea, genetically remains controversial. Previous researchers advocated a metamorphosed (-exhalative) sedimentary origin for iron enrichment. In this study, we present strong evidences for skarnification and Fe mineralization, spatially associated with the Myeongseongsan granite. The Pocheon deposit is composed of diverse carbonate rocks such as dolostone and limestone which are partially overprinted by various hydrothermal skarns such as sodic-calcic, calcic and magnesian skarn. Iron (-copper) mineralization occurs mainly in the sodic-calcic skarn zone, locally superimposed by copper mineralization during retrograde stage of skarn. Age data determined on phlogopites from retrograde skarn stage by Ar-Ar and K-Ar methods range from $110.3{\pm}1.0Ma$ to $108.3{\pm}2.8Ma$, showing that skarn iron mineralization in the Pocheon is closely related to the shallow-depth Myeongseongsan granite (ca. 112 Ma). Carbon-oxygen isotopic depletions of carbonates in marbles, diverse skarns, and veins can be explained by decarbonation and interaction with an infiltrating hydrothermal fluids in open system ($XCO_2=0.1$). The results of sulfur isotope analyses indicate that both of sulfide (chalcopyrite-pyrite composite) and anhydrites in skarn have very high sulfur isotope values, suggesting the $^{34}S$ enrichment of the Pocheon sulfide and sulfate sulfur was derived from sulfate in the carbonate protolith. Shear zones with fractures in the Pocheon area channeled the saline, high $fO_2$ hydrothermal fluids, resulting in locally developed intense skarn alteration at temperature range of about $500^{\circ}$ to $400^{\circ}C$.

• Restorative Dentistry and Endodontics
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• v.34 no.1
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• pp.42-50
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• 2009

Deterioration of long-term dentin adhesion durability is thought to occur by hydrolytic degradation within hydrophilic domains of the adhesive and hybrid layers. This study investigated the hypothesis that priming the collagen network with an organic solvent displace water without collapse and thereby obtain good bond strength with an adhesive made of hydrophobic monomers and organic solvents. Three experimental adhesives were prepared by dissolving two hydrophobic monomers, bisphenol-A-glycidylmethacrylate (Bis-GMA) and triethyleneglycol dimethacrylate (TEGDMA), into acetone, ethanol or methanol. After an etching and rinsing procedure, the adhesives were applied onto either wet dentin surfaces (wet bonding) or dentin surfaces primed with the same solvent (solvent-primed bonding). Microtensile bond strength (MTBS) was measured at 48 hrs, 1 month and after 10,000 times of thermocycles. The bonded interfaces were evaluated using a scanning electron microscope (SEM). Regardless of bonding protocols, well-developed hybrid layers were observed at the bonded interface in most specimens. The highest mean MTBS was observed in the adhesive containing ethanol at 48 hrs. With solvent-primed bonding, increased MTBS tendencies were seen with thermo cycling in the adhesives containing ethanol or methanol. However, in the case of wet bonding, no increase in MTBS was observed with aging.

• Korean Journal of Environment and Ecology
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• v.23 no.5
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• pp.431-438
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• 2009

The main purpose of this research is to prepare and provide basic materials for the propagational strategy of eelgrass by investigating on the morphological adaptation of Korean Zostera marina to ocean currents. An eelgrass plant mainly consists of rhizome, leaf sheath, leaves and roots. The rhizome is the horizontal stem of the plant that serves as the backbone from which the leaves and roots emerge. The leaf sheath is the bundle at the base of the leaves that holds the leaves together, protecting the meristem, the primary growth point of the shoot. Leaves originate from a meristem which is protected by a sheath at the actively growing end of the rhizome. As the shoot grows, the rhizome elongates, moving across or within the sediment, forming roots as it progresses. The aggregated leaves from the leaf sheath are found to have two cell layers on one side and multiple layers of airy tissues called aerenchyma on the other. The aerenchyma tissues are developed in multi-layered cell structures surrounding the veins which are formed in the leaf sheath. Generative shoots are made of rhizomes, which are circular or ovoidal, stem, and spathe and spadix. The transverse section of rhizome and the stem and central floral axis is found to be circular, ovoid and in the shape of convex respectively, and the vascular bundle, which is a part of transport system, has one large tube in the center and two small tubes on both sides. The layers of collenchyma cells numbered from 12 to 15 in the stem, and from 7 to 12 in the rhizome. The seed coat is composed of sclereids, small bundles of sclerenchyma tissues, which prevent the influx of sea water from the outside and help endure the environmental stress. In conclusion, alternative multi-layer structure in circular, convex type aggregated leaf base are interpreted to morphological adaption as doing tolerable elastic structure through movement of seawater. The generative shoots develop long slim stem and branches in circular or ovoidal shapes to minimize the adverse impacts of sea current, which can be interpreted as the plant's morphological adaptation to its environment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.235-244
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• 2011

The physicochemical properties and quality changes in salted and dried brown croaker products using deep seawater salt were investigated for preparation with different pretreatment, salting and drying conditions. Optimum salt concentration, salting time and drying time for product were 20% of body weight, 12 hrs at room temperature ($25{\pm}2^{\circ}C$), and 24 hrs at $30{\pm}2^{\circ}C$, respectively. The volatile basic nitrogen (VBN), peroxide value (POV), viable cell count and acid value (AV) of viscera and blade removed products were 18.9~22.4 mg%, 21.0~32.5 meq/L, and 2.3~4.4 mg/mL, $2.0\sim3.5{\times}10^3$ CFU/g, respectively and only viscera removed products were 31.2~38.1 mg%, 40~55.2 meq/L, 7.0~11.5 mg/mL, $4.1\sim5.5{\times}10^3$ CFU/g, respectively. Changes in quality of salted and dried brown croaker products were investigated during storage at room temperature and $5{\pm}2^{\circ}C$. The POV, AV and viable cell counts of salted and dried brown croaker products increased in commercial salt used and only viscera removed products compared with deep seawater salt used and viscera and blade removed products during storage time. Results in this study showed that the deep seawater salt was very effective for quality control of salted and dried brown croaker products and pretreatment method was a very important factor for preparation products. The optimum conditions for preparation of salted and dried brown croaker product were 20% of body weight for salt concentration, 12 hrs at $25{\pm}2^{\circ}C$ for salting time, and 24 hrs at $30{\pm}2^{\circ}C$ for drying time. Optimum storage time for quality maintenance was 14 days at $5{\pm}2^{\circ}C$.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.559-571
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• 2017

This study was conducted to determine the adhesive performances of plywoods affected by layering direction and the amounts of thermoplastic films. The face and back layers of veneer were hardwood species (Mixed light hardwood) and core layer veneer was radiata pine (Pinus radiata D. Don). Thermoplastic film used as adhesive were polypropylene (PP) film and polyethylene (PE) film. Thermal analysis and tensile strength were investigated on each films. As a result, the melting temperature of PP and PE films were $163.4^{\circ}C$ and $109.7^{\circ}C$, respectively, and the crystallization temperature were $98.9^{\circ}C$ and $93.6^{\circ}C$, respectively. Tensile strength and elongation of each films appeared higher on the width direction than length direction. Considering the characteristics of the thermoplastic films, the test for the amount of film used was carried out by layering film to the target thickness on veneer. The effecting of layering direction of film on plywood manufacturing was conducted by laminating in the length and width directions of the film according to the grain direction of veneer. Tensile-shear strength of plywood in wet condition was satisfied with the quality standard (0.7 MPa) of KS F 3101 when the film was used over 0.05 mm of PP film and over 0.10 mm of PE film. Tensile-shear strength of plywood after cyclic boiling exceeded the KS standard when PP film was used 0.20 mm thickness. Furthermore, higher bonding strength was observed on a plywood made with width direction of film according to grain direction of veneer than that of length direction of film. Based on microscopic analysis of the surface and bonding line of plywood, interlocking between veneers by penetration of a thermoplastic film into inner and cracks were observed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.789-796
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• 2016

The anti-lipogenic effect of cereal samples on high sucrose diet (HSD)-induced non-alcoholic fatty liver disease (NAFLD) in mice was studied. We divided C57BL/6 mice into various groups based on 8 weeks of treatment with three types of cereal samples (HSD+WR, HSD diet containing 40% white rice; HSD+MCG, HSD diet containing 40% mixed cereal grain; HSD+AO-MCG, HSD diet containing 40% mixed antiobesity-cereal grain). After the experimental period, body weight changes, liver weights, serum lipid profiles, and hepatic fatty acid metabolism-related gene expression levels were determined. We found that HSD+WR, HSD+MCG, and HSD+AO-MCG treatments reduced body weight and liver weight, especially HSD+MCG and HSD+AO-MCG effectively reduced levels of serum triglycerides, total cholesterol, and low-density lipoprotein cholesterol. However, high density lipoprotein cholesterol levels increased compared to the control group. Furthermore, expression of hepatic lipogenic genes such as sterol regulatory element-binding protein-1c, acetyl-coenzyme A carboxylase, fatty acid synthase, stearoyl-coenzyme A desaturase-1, cluster of differentiation, and $PPAR-{\gamma}$ (peroxisome proliferator activated receptor ${\gamma}$) decreased, whereas expression of ${\beta}-oxidation$ genes such as $PPAR-{\alpha}$ and carnitine palmitoyl transferase-1 increased following HSD+MCG and HSD+AO-MCG treatment compared with levels in HSD+WR and control groups. These results suggest that the functional cereal samples, especially HSD+AO-MCG treatment, improved hepatic steatosis triggered by an HSD-induced imbalance in hepatic lipid metabolism.

• Applied Microscopy
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• v.41 no.1
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• pp.47-53
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• 2011

Hair is an appendage of skin which protects the body from outer physical and chemical stimuli. Hair is generated from the hair follicle lying on a sunken basal layer of epidermis. Hair cycling, which regenerates hair follicles throughout the life time of the organism. Numerous kinds of factors which exist at the hair follicle have been reported to regulate hair cycling, Human growth hormone secreted from pituitary gland, initially demonstrated to accelerate organ's growth, has been reported to play a role in the biology of organ size determination. We investigated the effect of 6-histidines residues tagged at amino-terminus of human growth hormone using light and electronmicroscopic methods. Human growth hormone encapsulated in nano-liposome (LhGH) was used to find how LhGH affects hair follicle cycling of mouse (C57BL6/CrN). Distilled water as a negative control, 3% Minoxidil as a positive control, and LhGH were applied to mouse for weeks. LhGH increased the number of exposed hairs per given areas ($1mm^2$). This result was also confirmed using a different breed of mice which show natural hair loss in an old age (about 17 months after birth). When LhGH was applied for 3 weeks after natural hair loss, natural hair loss on these mice was prevented, However, the control group mice on which LhGH was not applied showed further hair loss. This result indicates that LhGH may stimulate hair cycling of mouse. In clusion, it is cleat that the LhGH increased the number of hair on mice and help the depilated skin to grow new hair follicles again.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.309-316
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• 2008

This study was carried out to examine the effects of vitamin E on chronic gastric ulcer induced by alcohol treatment in rats. Chronic gastric ulcer model was established by oral administration of 70% ethanol at one time and supply of 15% ethanol for additional 7 days. Male Sprague-Dawley rats, approximately 200 g, were fasted for 24 hours and orally gavaged with 1 mL of 70% ethanol for the induction of acute ulcer. A supply of 15% ethanol dissolved in distilled water for 7 days were followed to maintain chronic gastric ulcer. Acute ulcer group was sacrificed at 3 hours after oral administration of 1 mL of 70% ethanol. Chronic groups were divided into three groups according to vitamin E levels; low-vitamin E (LVE, 0 mg/mL oil/day), normalvitamin E (NVE, 1 mg/mL oil/day) and high-vitamin E (HVE, 10 mg/mL oil/day). These groups were fed vitamin E free diets which were made of vitamin E free vitamin mix followed AIN-93M pattern for 7 days. Histological findings of congestion, hemorrhage and necrosis in gastric tissue were shown severely in acute ulcer group and LVE group of chronic ulcer groups. The concentration of gastrin in serum was significantly higher in LVE group. The content of histamine in stomach was lower in acute ulcer group but there was no significant difference among the chronic groups regardless of vitamin E levels. Content of malondialdehyde (MDA) in gastric tissue was higher in HVE group and activities of antioxidant enzyme, glutathione peroxidase (GPx) and catalase, were lower in HVE group. Myeloperoxidase (MPO) activities as a marker of neutrophils infiltration was significantly higher in LVE group. These results suggested that vitamin E supplementation has positive effects on healing of alcohol-induced chronic gastric ulcer through alleviation of gastric tissue injuries and reduction of the MPO activity in gastric tissue and gastrin in serum.

• Culinary science and hospitality research
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• v.21 no.1
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• pp.281-296
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• 2015

This study performed to find proper temperature and improve texture and taste of pickle by considering physic-chemical characteristic and sensory evaluation. The basis temperature of the pickle was manufactured by 5 temperatures($95^{\circ}C$, $85^{\circ}C$, $75^{\circ}C$, $65^{\circ}C$, $5^{\circ}C$) at intervals of $10^{\circ}C$, and the dangerous Temp range was exempted during 12 days. Results showed that 3rd day at $95^{\circ}C$ was the best temperature for the quality specification of the pickle. In addition, between 6th to 12nd days at $85^{\circ}C$ and $95^{\circ}C$ appeared the most excellent preferences of the pickles. Thus, quality specifications showed different results by the date, and it appeared $95^{\circ}C>85^{\circ}C>75^{\circ}C>65^{\circ}C>5^{\circ}C$ in order. Furthermore, the liquid pickles at the temp of $95^{\circ}C{\sim}85^{\circ}C$ showed better texture and flavor of pickles as well as good preference. Based on these results, managers or administrators of foodservice business will be recognized the importance of temperature and storage period for salted pickles to improve its texture and taste along with improving quality and preference.