• Journal of Nutrition and Health
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• v.25 no.2
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• pp.123-131
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• 1992

Concentrations of 5 major minerals(Na, K, Ca, P, Mg) and 3 trace elements(Mn, Mo, Ni) were measured in human milk samples collected from 21 highly selected healty lactating women at 2-5 days and at 1, 2, 4, 6 and 12 weeks postpartum. Significant decrease in contents of the major minerals and trace elements were found with time postpartum. Sodium contents decreased from 293.01ug/N at 2-5 days to 194.27ug/N at 12 weeks. Potassium contents also decreased from 436.18ug/N in colostrum to 358.51ug/N in matured milk at 12 weeks. The Ca/P ratios of colostrum transitional and matured milk were 3.39, 281 and 2.45 respecti-vely. Mean manganese levels of colostrum and transitional were 0.024ug/N and those of matured milk were 0.014ug/N. Molybdenum concentrations in the breast-milk collected at 1, 2, 4 weeks were higher than those in the milk samples at 2-5 days and 12 weeks Nickel content of colostrum was 0.062ug/N and those of trnsitional matured milk were 0.22ug/N and 0.017ug/N, These determinations will provide the basic information on the variability of minerals and trace elements as lactation proceed and the comparison of the components between term and preterm milk.

• Journal of Nutrition and Health
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• v.44 no.1
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• pp.29-40
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• 2011

The purpose of this study was to examine the association among bone mineral density (BMD), biochemical bone markers, nutrients, and salt intake in premenopausal and postmenopausal women. We evaluated 431 subjects who visited a health promotion center of a university hospital between January 2008 and July 2009. We excluded those who were taking medications or who had an endocrine disorder affecting osteoporosis. The subjects were divided into premenopausal (n = 283) and postmenopausal (n = 143) women. We evaluated the correlation among BMD of the lumbar spine, femoral neck, and total femoral, as well as biochemical bone markers, hormone, serum profiles, general characteristics, nutrient intakes, and food intake frequencies. From a stepwise multiple regression analysis, lumbar spine BMD was positively correlated with weight (p < 0.001) and negatively correlated with osteocalcin (OC)(p < 0.001), Femoral neck BMD was positively correlated with weight (p < 0.001) and negatively correlated with C-telopeptide (CTx) and alkaline phosphatase (ALP)(p < 0.001, p < 0.05). In premenopausal women, femoral total BMD was positively correlated with BMI (p < 0.001) and negatively correlated with CTx (p < 0.001). In postmenopausal women, lumbar spine BMD was positively correlated with calcium intake (p < 0.01) and negatively correlated with sodium intake (p < 0.01). Femoral neck and femoral total BMD were both positively correlated with weight (p < 0.001), and femoral neck BMD was negatively correlated with age and ALP (p < 0.001, p < 0.05). Femoral total BMD was negatively correlated with age and OC (p < 0.001, p < 0.01). These results suggest that reducing sodium intake may play an important role delaying bone resorption and preventing a decrease in BMD.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.119-126
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• 1987

This study was conducted to elucidate the most appropriate method to obtain auxotrophic mutants from Valsa ceratosperma, the causal fungus of apple canker, which may be used as a gene marker in detecting the transfer of the factors of avirulent strains to virulent strains. Among the 3 kinds of synthetic media tested, each have two formula for minimal and complete, the medium which has been used in study of Endothia parasitica (E. P medium) was turned out to be most appropriate for the growth of V. ceratosperma. A medium for single colony formation from pycnidiospore of this fungus was developed by adding 0.5% L - sorbose to the E. P minimal medium. The period of incubation in dark for preventing the photoreactivation after U. V irradiation was estimated as about 60hrs at which most of the spores become binucleate. Largest number of putative auxotrophs were obtained at about 50second of irradiation to the spores smeared on the medium for single colony formation, at which the survival rate of spores was 5 to 6 percent. With these method developed in this experiment, 161 isolates of putative auxotrophs were detected among which the nutrient requirement for 10 isolates were determined. Five out of 10 mutants were still virulent to apple tree and all but one could not sporulate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.612-617
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• 1999

The quality characteristics of 15 kinds of the commercial northern sand lance, Ammodytes Personatus sauce (CNS) of korean traditional salt-fermented fish sauces were evaluated comparing to the traditional northern sand lance, Ammodytes Personatus sauce (TNS). The ranges of chemical compositions of the CNSs were $66.5\~71.0\%$ moisture, $19.3\~24.6\%$ ash, $4.7\~12.0\%$ crude protein, and the pH and salinity were $5.56\~6.47\%,\;24.0\~32.9\%$, respectively. Total nitrogen, amino nitrogen, total free amino acid and total ATP related compounds (sum of ATP$\~$IMP, HxR, Hx and uric acid) were in the ranges of 0.781$\~$ 1,918 g, 445.9$\~$1037.9 mg, 3,258.9$\~$6:562.6mg in 100 ml CNSs, and 4.766$\~$8.989 $\mu$mol in 1 ml CNSs. The CNSs were higher in content of moisture, TMAO, TMA and pH, but lower in content of crude protein, salinity, total nitrogen, amino nitrogen, total ATP related compounds, absorbance at 453 nm and total free amino acid than the TNSs, Both CNS and TNS samples were rich in free amino acids, such as glutamic acid, lysine, alanine, leucine, valine, aspartic acid and isoleucine in the order.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.416-419
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• 1999

To evaluate lipid oxidation in dried shellfish during storage, brown pigment formation and composition of fatty acid were determined. Levels of brown pigment formation occurred at $25^{\circ}C$ were higher than those occurred at $4^{\circ}C$ throughout the storage period. Especially, the formation content of lipophilic brown pigment was 9$\~$10 times higher than that of hydrophilic brown pigment in all samples. Fatty acid composition of total lipid (TL) in fresh sea mussel and baby clam were $34.21\%$ and $32.83\%$ in saturated fatty acid, $19.50\%$ and $20,83\%$ in monoenoic acid, and $46.29\%$ and $46.79\%$ in polyenoic acid, respectively. The prominent fatty acids were 16:0, 16:1 and 20:5 in TL of the both samples. During storage, the contents of saturated fatty acid and monoenoic acid were slightly increased but that of polyenoic acid was decreased. In sea mussel, the content of polyenoic acid was higher in phospholipid (PL) than in neutral lipid (NL), while saturated fatty acid and monoenoic acid content were higher in the latter. The ratios of polyenoic acid/saturated fatty acid (P/S) in NL was similar in all samples. But the ratio of P/S in PL was higher in baby clam ($1.81\%$) than that in sea mussel($1.42\%$).

• Journal of Intelligence and Information Systems
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• v.22 no.2
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• pp.81-96
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• 2016

As the internet has become widespread and easy to access everywhere, it is common for people to search information via online search engines such as Google and Naver in everyday life. Recent studies have used online search volume of specific keyword as a measure of the internet users' attention in order to predict disease outbreaks such as flu and cancer, an unemployment rate, and an index of a nation's economic condition, and etc. For stock traders, web search is also one of major information resources to obtain data about individual stock items. Therefore, search volume of a stock item can reflect the amount of investors' attention on it. The investor attention has been regarded as a crucial factor influencing on stock price but it has been measured by indirect proxies such as market capitalization, trading volume, advertising expense, and etc. It has been theoretically and empirically proved that an increase of investors' attention on a stock item brings temporary increase of the stock price and the price recovers in the long run. Recent development of internet environment enables to measure the investor attention directly by the internet search volume of individual stock item, which has been used to show the attention-induced price pressure. Previous studies focus mainly on Dow Jones and NASDAQ market in the United States. In this paper, we investigate the relationship between the individual investors' attention measured by the internet search volumes and stock price changes of individual stock items in the KOSDAQ market in Korea, where the proportion of the trades by individual investors are about 90% of the total. In addition, we examine the difference between industries in the influence of investors' attention on stock return. The internet search volume of stocks were gathered from "Naver Trend" service weekly between January 2007 and June 2015. The regression model with the error term with AR(1) covariance structure is used to analyze the data since the weekly prices in a stock item are systematically correlated. The market capitalization, trading volume, the increment of trading volume, and the month in which each trade occurs are included in the model as control variables. The fitted model shows that an abnormal increase of search volume of a stock item has a positive influence on the stock return and the amount of the influence varies among the industry. The stock items in IT software, construction, and distribution industries have shown to be more influenced by the abnormally large internet search volume than the average across the industries. On the other hand, the stock items in IT hardware, manufacturing, entertainment, finance, and communication industries are less influenced by the abnormal search volume than the average. In order to verify price pressure caused by investors' attention in KOSDAQ, the stock return of the current week is modelled using the abnormal search volume observed one to four weeks ahead. On average, the abnormally large increment of the search volume increased the stock return of the current week and one week later, and it decreased the stock return in two and three weeks later. There is no significant relationship with the stock return after 4 weeks. This relationship differs among the industries. An abnormal search volume brings particularly severe price reversal on the stocks in the IT software industry, which are often to be targets of irrational investments by individual investors. An abnormal search volume caused less severe price reversal on the stocks in the manufacturing and IT hardware industries than on average across the industries. The price reversal was not observed in the communication, finance, entertainment, and transportation industries, which are known to be influenced largely by macro-economic factors such as oil price and currency exchange rate. The result of this study can be utilized to construct an intelligent trading system based on the big data gathered from web search engines, social network services, and internet communities. Particularly, the difference of price reversal effect between industries may provide useful information to make a portfolio and build an investment strategy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.704-713
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• 1997

This study was conducted to describe qualitatively the protein metabolism of pigs during growth depending on the feed protein quality and to describe quantitatively amino acids requirements, using a simulation model. The used model has a non-linear structure. In the used model, the protein utilization system of a pig, which is in the non-steady-state, is described with 15 flux equations and 11 differential equations and is composed with two compartments. Protein deposition(g/day) of pigs on the 30th, 60th, 90th, and 120th day of feeding duration with three-quality protein, beginning with body weight 20kg, were calculated according to the empirical model, PAF(the product of amino acid functions) of Menke, and was used as object function for the simulation. The mean of relative difference between the simulated protein deposition and PAF calculated values, lied in a range of 8.8%. The simulated protein deposition showed different behavior according to feed protein quality. In the high-quality protein, it showed paraboloidal form with extending growth simulation up to 150eh day. So the maximum of protein deposition was acquired on the 105th day of simulate growth time and then it decreased fast. In the low-quality protein, this form of protein deposition in the course of simulated growth did not appear until 150th day. The simulated protein mass also showed a difference in accordance with feed protein quality. The difference was small on the 30th day of simulated growth, but with duration of the simulated growth it was larger. On the 150th day the simulated protein deposition of high quality protein was 1.5 times higher as compared to the low-quality protein. The simulated protein synthesis and break-down rates(g/day) in the whole body showed a parallel behavior in the course of growth, according to feed protein quality. It was found that the improvement of feed protein quality increased protein deposition in the whole body through a increase of both protein synthesis and breakdown during growth. Also protein deposition efficiency, which was calculated from simulated protein deposition and protein synthesis, showed a difference in dependence on the protein qualify of feed protein. The protein deposition efficiency was higher in pigs fed with high quality protein, especially at the simulation time 30th day. But this phenomena disappeared with growth, so on the 150th day of growth, the protein deposition of the high feed protein quality was lowest among the three different quality of feed protein. The simulated total requirement of the 10 essential amino acids for the growth of pigs was 28.1(g/100g protein), similar to NRC. The requirement of lysine was 4.2(g/100g protein).

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.945-954
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• 2006

The purpose of this study is to present basic data for an improvement of school foodservice by indentifying students' preference level for school meal menu and assessing students' nutrition intake. The subjects participated in this study were 544 high school students on 1st grade served by self-operated school foodservice in Daegu. The frequency analysis, t-test analysis, and correlation analysis were carried out for the data analysis using SPSS 12.0 program. Based on the results toward students' preference and serving frequency, the most frequently offered food was soup sorts and then followed by the categories of boiled rice, kimchi, broiled food and hard-boiled food. Boiled rice, rice with assorted vegetables, mandu soup, salad and braised beef rib were highly preferred to the students. Male students scored higher preference to the menu related with meats than female students. However, the students' preference and serving frequency on the menu were not correlated significantly in this study. A substantial correlation was found between the degree of preference and the rate of intake (p<0.01). It would be generalized that preferences to menu items strongly sffected the level of intake by students. The nutrient analysis of food intake revealed that both male and female students were not consuming sufficient level of calorie, calcium and vitamin $B_2$. In conclusion, the results indicate that the students' preference is a very important variable influencing the consumption level of meal as well as balanced nutrient intake by students served in school foodservice. Menu planning should be integrated into school foodservice management for quality control. As limited control of the menu may also negatively influence on the food leftovers and ecological issues, professionals related to the school foodservice including administers, educators and dieticians need to check up the students' preference regularly and reflect their perception on the menu planning to improve the quality of school foodservice. The nutrient intake currently provided through school foodservice should be also assessed more thoroughly. These data could be incorporated into continuous quality improvement and strategic planning in school foodservice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.333-341
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• 2016

This study examined the beauty food activities of water and ethanol extracts from Tetragonia tetragonioides. Content of phenolic compounds extracted with water and 50% ethanol extracts were 3.29 mg/g and 4.14 mg/g, respectively. 1,1-Diphenyl-2-picrylhydrazyl free radical scavenging activities of water and ethanol extracts were 98.45% and 91.20%, respectively, at $200{\mu}g/mL$ of phenolics. 2,2'-Azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical decolorization activity was 97.28% for water extracts and 97.83% for ethanol extracts at $100{\mu}g/mL$ of phenolics. Antioxidant protection factor (PF) was 1.77 PF for water and ethanol extracts at $200{\mu}g/mL$ of phenolics. Thiobarbituric acid reactive substances of water and ethanol extracts were 94.77% and 95.64%, respectively, at $100{\mu}g/mL$ of phenolics. Tyrosinase inhibitory activity, which is related to skin-whitening, was confirmed to be 34.96% for ethanol extracts at $200{\mu}g/mL$ of phenolics. Elastase inhibitory activity and anti-wrinkle effect of 50% ethanol extracts were 78.9% at $200{\mu}g/mL$ of phenolics. Collagenase inhibitory activity of ethanol extracts was 61.29% at $200{\mu}g/mL$ of phenolics. Astringent effect was not detected in water extracts but was 7.82% for 50% ethanol extracts at $200{\mu}g/mL$ of phenolics. Hyaluronidase inhibitory activity as a measure of anti-inflammation was confirmed to be 81.04% for water extracts at $200{\mu}g/mL$ of phenolics. Based on these results, Tetragonia tetragonioides extracts can be used as a functional material and functional beauty food with antioxidant effects.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.420-436
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• 2016

The purpose of this study was to identify the status of task performance and working conditions for nutrition teachers in order to determine new ways to improve the current nutrition system and increase job satisfaction among teachers. From the 14th of July to the 26th of September 2014, email questionnaires were distributed to and collected from 311 nutrition teachers nationwide, including teachers at elementary, middle, and high schools. The results are as follows. First, over 90% of nutrition teachers indicated that their work was demanding. In particular, 63.5% of nutrition teachers at high schools worked more than 40 hours of overtime per month. Second, 73% of nutrition teachers provided nutrition education, but the percentage significantly decreased at upper levels of school. Nutrition teachers had difficulties teaching due to the absence of standard teaching materials and a lack of time due to excessive work. Teachers also wanted 30 hours of job training once per year during their vacation organized by the regional Department of Education. Third, around half of the nutrition teachers considered that promotion and transfer professions are necessary for systematic foodservice and education. An additional allowance was demanded by nutrition teachers at schools that serve two or three meals per day. Considering the results, alleviating the workload of nutrition teachers and more time preparing nutrition classes for student are required. Fair evaluation of job performance that considers work conditions of nutrition teachers should be considered.