• Journal of the Korean earth science society
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• v.37 no.4
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• pp.218-229
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• 2016

The bedform stability diagram indicates the shape and size of bedforms that will occur to a given grain size and flow velocity. The diagram has been constructed from experimental data which have been mostly acquired by flume experiments. Generally, the flume experiments have been performed on well sorted sediments with unimodal grain size distribution, in order to understand relationship between grain size and flow velocity. According to the diagram, a ripple structure initiates to be formed from lower flow regime flat bed, as the flow velocity increases on the surface of fine-sand or medium-sand sediments. This study aims to verify that the experimental result of bedform stability diagram will be reproduced in our flume experimental systems, and also to confirm that the result is consistent not only on well-sorted sand sediments but also on poorly-sorted sand sediments with bimodal grain size distribution. The experimental results in this study show that initiation of 2D or 3D ripple structure on poorly-sorted sand sediments requires higher flow velocity and shear stress than those for initiation of the structure on well-sorted sand sediments. In general, carbonate sediments are characterized by poor sorting due to inactive hydraulic sorting and bimodal grain size distribution with allochems and matrices. The results suggest that the carbonate depositional system possibly need a higher flow velocity for initial formation of 2D or 3D bedform structures. The reason might be the fact that pulling off and lifting of a grain in poorly sorted sediments require more energy due to sorting, friction, stabilization, armour effects, and their complex interaction. This preliminary study warrants additional experiments under various conditions and more accurate analysis on the relationship between formation of bedforms and grain size distribution.

• Journal of Life Science
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• v.20 no.12
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• pp.1812-1819
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• 2010

Skipping breakfast is a risk factor closely related to metabolic syndrome and obesity. We analyzed the relationship between breakfast size, metabolic syndrome and obesity. The study included 5,548 adults who visited a health promotion center at Pusan National University from January to November of 2006. Subjects were divided into four groups according to breakfast size - skipper group (no breakfast), small intake group, medium intake group and large intake group. 959 (17.3%) of the 5548 subjects were included in the Skipper group. Intake of daily calories, proteins, carbohydrates and fats was the lowest in the Skipper group. Breakfast size increased linearly with an increased intake of daily calories, proteins, carbohydrates and fats. Body mass index ($23.4\;kg/m^2$) and waist circumference (79.6 cm) were the lowest in the Small intake group. In the Small intake group, triglycerides, fasting plasma glucose, systolic blood pressure and diastolic blood pressure were the lowest, and high density lipoprotein cholesterol levels were the highest. The number of metabolic risk factors was the lowest in Small intake group. Odds ratio of metabolic syndrome (Odds ratio=0.612) was the lowest in Small intake group. Along with increasing breakfast size, the odds ratio also increased. In this study, breakfast size was found to influence metabolic risk factors. Skipping breakfast worsened metabolic risk factors, while a small breakfast size had a favorable effect on metabolic risk factors.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.2
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• pp.119-125
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• 2012

The tributary water quality and flowrate monitoring result, which is fundamental data for the establishment of the water environmental policy, is used as very important data for the implementation of TMDL. This study introduced how to use the tributary water quality and flowrate monitoring data for the analysis of the watersheds, the satisfactory assessment of water quality standards in the watersheds, the selection of watersheds for the establishment of the implementation plan, and the selection of the tributary catchments for improving the water quality using a stream grouping method. According to the analytical results of tributary catchment using water quality and flowrate monitoring data of thirty-seven tributaries in the Geum-River watershed at Chungcheongnam-do, the value of flowrate in the tributaries, which is located in the middle-lower Geum-River watershed, was greater than the other areas and the concentration of the water pollutants regardless of water quality parameters in the tributaries at Nonsancheon catchment was relatively higher than the other areas. The problems, which have the determination of satisfaction of water quality standards and selection of target watersheds for establishment of the implementation plan regardless of the water quality of tributary in the watershed due to the water quality and flowrate monitoring results of the main river, were improved use of the results of tributary water quality and flowrate monitoring. Also, the tributary catchments for improving the water quality, according to stream grouping method based on the results of tributary water quality and flowrate monitoring, were selected. In the Geum-River watershed at Chungcheongnam-do, the tributary in the Nonsancheon, Byeongcheoncheon, Seokseongcheon, Jocheon catchments, which has a large flow and a high concentration of water pollutants, should be preferentially selected for improving the water quality of the tributary in accordance with the reduction of the source of pollution.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.3
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• pp.183-189
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• 2013

Purpose: The aim of this study was to evaluate clinical outcomes of implant supported fixed-hybrid prostheses (FHP) in the fully edentulous arches. Materials and methods: Patients in this retrospective study were restored with fixed-hybrid prostheses supported by 4 to 6 implants and functioned more than 1 year of loading. Outcome measures were marginal bone change of implant related with sex, anatomical location (maxilla vs. mandible), opposing teeth, loading time of patients, tilting of posterior implant by Mann- Whitney U test and cantilever length of superstructure by regression analysis, and complication rates. Significance level was set P<.05. Results: A total number of 84 implants (16 restorations) placed in 16 patients were observed for 28 months and mean marginal bone loss was $0.53{\pm}0.39mm$. There were no differences of marginal bone loss according to sex, anatomical location (maxilla vs. mandible), opposing teeth, loading time of patients (P>.05), and cantilever length was not significantly related with a marginal bone loss of implant next to cantilever (P>.05). Complication was shown in 11 patients and veneer fracture and dislodging of artificial teeth were most prevalent. Conclusion: Within the limitations of this study, although marginal bone loss of FHP was very little, complication rates were high. Irrespective of tilting of most posterior implants, marginal bone loss of most posterior implants next to cantilever was less than those of the other implants positioned anteriorly. Cantilever length (<17 mm) did not affect a marginal bone loss of most posterior implants.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.182-185
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• 2011

This study was conducted to develop an appropriated management for safety of children snacks sold around school. Total 598 items as targeted food were collected; 66 biscuits, 320 candies, 57 chocolates, 40 ice creams and 115 beverages. Microbiological hazards such as total aerobic bacteria, Coliforms, Escherichia coli, Bacillus ceruse, Yeasts & molds were measured by analytical method in Korean food code. Total aerobic bacteria and Yeasts & molds were detected in cookies at the level of less than 2.69 and 2.65 $log_{10}$ CFU/g and the detection rates were 54.55 and 62.12%, respectively. Bacillus cereus was detected in 1 snack only at the level of 1.39 $log_{10}$ CFU/g but it was less than Korean microbial standards and specifications (3 $log_{10}$ CFU/g). Total aerobic bacteria and Yeasts & molds were detected in candies less than 2.86, 3.36 $log_{10}$ CFU/g and the detection rates were 46,8% respectively. Total aerobic bacteria, Yeast & mold were detected in chocolates at the levels less than 2.52 and 1.87 $log_{10}$ CFU/g and the detection rates were 33 and 22% respectively. Total aerobic bacteria in both ice creams and beverages were detected at the levels less than 3.39 and 1.35 $log_{10}$ CFU/g and the detection rates were 82 and 5% respectively. Coliforms were found in one ice cream (1.39 $log_{10}$ CFU/g) only. The result of this study indicated that all children snacks around school were suitable for microbial standard and specifications in Korean Food Code. However, since most children snacks around school are circulated without proper storage temperature and handing condition, consistent microbial management for children snacks are needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1366-1374
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• 2016

Most elderly have difficulties in managing food safety and nutrition by themselves. Various nutrition educations for the elderly have been developed, but food safety and nutrition education program and educational tools for the elderly are very limited. The aim of the study was to evaluate a food safety and nutrition education program based on the Health Belief Model (HBM) for the elderly. Education program was implemented for 220 seniors (137 educated group and 83 control group) aged over 65 years at senior welfare community centers. The intervention study was carried out on a weekly basis during each of 5 weeks, and each session lasted about 35 or 40 minutes. The effectiveness of the program was assessed with a questionnaire before and after education. Education program consisted of a 5 week program, and topics were 'Dietary changes for the elderly's healthy life', 'Prevention of food poisoning in everyday life', 'Safe food handling for my health', 'Healthy dietary life to prevent chronic disease', and 'Safety! nutrition! healthy dietary life'. Education program materials such as slides, handouts, videos, leaflet, and booklets were developed. As a result, there were score improvements in knowledge, dietary behaviors, and health belief after intervention in the intervention group, which were higher than those of the control group. In particular, there was a meaningful interrelation between dietary behavior and health belief (r=0.520, P<0.001). This finding suggests that changing beliefs is very important to make desirable dietary behavioral changes. For this reason, we can conclude HBM theory is an effective model to educate nutrition and food safety for the elderly. Furthermore, food safety and nutrition education programs are implemented and delivered continuously at various settings such as a health center or community welfare center, and those will contribute significantly to enhance perception and change their desirable dietary behaviors for the elderly.

• Korean Journal of Microbiology
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• v.44 no.3
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• pp.178-185
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• 2008

Avian influenza virus (AIV) is recognized as key to the emergence of pandemic influenza for humans; there are growing concerns that AIV H9N2 may become more efficient to transmit to humans in the near future, since the infection of poultry with AIV H9N2 has been common in recent years. In this study, we aimed to produce antisera recognizing the HA and NA proteins of AIV H9N2. Initially, coding sequences corresponding to the N-terminal regions of the HA and NA proteins of the Korean AIV H9N2 (A/Ck/Kr/MS96/96) isolated from a domestic chicken were amplified from the genomic RNA. Following cloning of the amplified cDNA fragments into pGEX4T-1 vector, two GST-fusion proteins (GST-HAln and GST-NAn) were expressed in E. coli BL21 and purified with glutathione sepharose columns; the recombinant GST-HAln and GST-NAn proteins were both used as immunogens in rabbits. The antigenicity of the rabbit antisera was analyzed by immunoblotting of the cell lysates prepared from AIV H9N2-infected MDCK cells. Overall, the recombinant HAln and NAn proteins fused to the C-terminus of GST and the rabbit antisera raised against the corresponding recombinant proteins would provide a valuable reagent for AIV diagnosis and basic research.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.301-305
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• 2012

This study was conducted to investigate the microbiological contamination levels in rice cakes and rice flour due to climate change in three areas classified to their temperature and precipitation. We investigated the contamination levels of total aerobic bacteria, coliforms, Escherichia coli, Bacillus cereus, Staphylococcus aureus, Clostridium perfringens of rice flour and 3 rice cakes such as Garaetteok, Sirutteok and Gyeongdan. Contamination levels of total aerobic bacteria in rice flour were 4.9 log CFU/g. In a total of 70 rice flour, yeasts & molds and coliforms were detected in 42 and 52 samples at the levels of 43 CFU/g and 1.29 log CFU/g, respectively. S. aureus were detected in only 1 rice flour (1.66 log CFU/g) out of 70. In an investigation of contamination levels in rice cakes, the population of total aerobic bacteria were highest in Gyeongdan (5.18 log CFU/g) and coliforms were highest in Gareattock (2.93 log CFU/g). There was no detection of E. coli and B. cereus except for only 1 Gareattock (1.20 log CFU/g). There were no differences of contamination levels among the three areas. If constant monitoring of rice cakes and rice flour is conducted on the basis of this study, it is expected to be able to analyze the change of contamination levels in rice cakes and rice flour due to climate change.

• Food Science and Preservation
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• v.24 no.7
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• pp.957-964
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• 2017

The purpose of this study was to determine the optimum spray drying conditions of soft persimmon latte using response surface methodology that is a statistical procedure used for optimization studies. A central composite design was applied to investigate the effects of independent variables, inlet temperature ($X_1$), air flow rate ($X_2$), and feed flow rate ($X_3$), on responses such as yield, water absorption index, and total phenolic compounds. Statistical analysis revealed that independent variables significantly affected all the responses. A maximum yield of 8.11 g was obtained at $90^{\circ}C$ of $X_1$, 51.82 mL/min of $X_2$ and 7.00 mL/min of $X_3$. A minimum water absorption index of 0.58 was obtained at $101^{\circ}C$ of $X_1$, 60.00 mL/min of $X_2$ and 17.00 mL/min of $X_3$. A maximum total phenolic compounds of $298.02{\mu}g/mL$ was obtained at $90^{\circ}C$ of $X_1$, 43.33 mL/min of $X_2$ and 17.00 mL/min of $X_3$. In conclusion, the best spray drying conditions were as follows: $X_1$, $90^{\circ}C$; $X_2$, 53 mL/min; $X_3$, 17 mL/min. Under those optimal conditions, the powder's yield (7.46 g), water absorption index (0.54), and the content of total phenolic compounds ($294.75{\mu}g/mL$) were estimated.

• The Journal of the Petrological Society of Korea
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• v.19 no.1
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• pp.1-18
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• 2010

On the ArcGIS 9.2 program in Gyeongsangbug-Do and Daegu areas, distribution ratios of rock types and geologic ages were obtained from the 1 : 250,000 scaled digital geologic and geomorphic maps. The obtained distribution ratios here will be used the geologic information data for industrialization and development planning of rock resources. The Gyeongsangbug-Do area consists of 86 rock types that can be divided into 10 large groups in geologic age. Their geologic distribution ratios show the decreasing in the order of Cretaceous, Precambrian, Jurassic, Quaternary, Age-unknown and Tertiary, all of which occupy the prevailing ratio of 96.30% in the area. Of which, sixteen rock types are somewhat dominant ones (64.04%). They are of Precambrian Yulri group and granite gneiss of the Yeongnam metamorphic complex and biotite gneiss of the Sobaegsan metamorphic complex, Age-unknown granite, Jurassic granite, Cretaceous Gasongdong and Dogyedong formations of the Yeongyang sub-basin, Nagdong and Chunsan formations and intermediate-basic volcanics of Euiseong sub-basin, Jinju and Jindong formations and andesite-andesitic tuff of Milyang sub-basin, and hornblende granite, and Quaternary alluvium. They show relatively narrow ranges of 2.07-6.53% in geologic distribution in exception of Jurassic granite showing 13.14%. And the rest 70 rock types appear to very narrow range between 0.01 and 1.94 %. On the other hand, twelve rock types are developed in the Daegu area. Their geologic ages appear to be classified into Cretaceous and Quaternary occupying 86.05% and 11.39%, respectively. Seven rock types take possession of 94.04% among the all rocks. The major rock types are Jinju formation of the Sindong group, Chilgog, Haman and Jindong formations of the Hayang group, andesite and andesitic tuff, hornblende granite and Quaternary alluvium. With exception of andesite and andesitic tuff of 37.40%, the types show slightly wide range of 3.25-17.39%, which apparently differ trends from that of Gyeongsangbug-Do area. And the rest of rock types have narrow ranges of 0.22-1.81% in the Daegu area.