• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.371-377
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• 2009

The objectives of the present study were to investigate the effects of different dietary ratios of whole-crop corn silage and alfalfa hay on nitrogen (N) digestion, duodenal flow and metabolism across the portal-drained viscera (PDV) of growing beef steers, and to elucidate their relationships. Four steers (236${\pm}$7 kg BW) fitted with duodenal cannulae and chronic indwelling catheters into the portal and mesenteric veins and abdominal aorta were used in a 4${\times}$4 Latin square design. Animals were fed (at 12-h intervals) the 4 diets consisting of whole-crop corn silage (C) and alfalfa hay (A) in 80:20 (C8A2), 60:40 (C6A4), 40:60 (C4A6) and 20:80 (C2A8) ratios of which dietary crude protein (CP) was 10.5, 12.0, 13.5 and 15.0% of dry matter (DM), respectively. Feeding level was restricted to 95% of ad libitum intake to measure N digestion, blood flow and net flux of N across the PDV. Digestibility of DM and neutral detergent fiber and digestible energy intake linearly increased as the ratio of alfalfa hay increased. The N intake, duodenal flow and intestinal disappearance increased linearly with increasing alfalfa hay. Arterial and portal concentrations of ${\alpha}$-amino N showed a quadratic response to increasing levels of alfalfa hay and were the highest in steers fed the C6A4 diet. The net PDV release of ${\alpha}$-amino N and ammonia N increased linearly with increasing alfalfa hay, but urea N uptake by PDV did not differ among diets. As a percentage of apparently digested N in the total gut, net PDV release of ${\alpha}$-amino N linearly decreased from 66 to 48% with increasing alfalfa hay. Conversely, net PDV recovery of ${\alpha}$-amino N to intestinal N disappearance varied with increasing alfalfa hay accounting for 49, 50, 58 and 61% on C8A2, C6A4, C4A6 and C2A8 diets, respectively. Net PDV uptake of urea N, relative to apparently digested N, linearly decreased from 81 to 25% as alfalfa hay increased from 20 to 80% of DM intake. Considering PDV uptake of urea N, microbial efficiency and conversion of total tract digested N to PDV ${\alpha}$-amino N net supply, a diet consisting of 80% whole-crop corn silage and 20% alfalfa hay (10.5% CP) was the best, while considering the quantities of intestinal N disappearance and ${\alpha}$-amino N absorption, a diet of 20% whole-crop corn silage and 80% alfalfa hay (15% CP) would be preferred. The proportion of ${\alpha}$-amino N recovered by PDV relative to the intestinal N disappearance may vary with energy intake level of mixed forage diets.

• The Korean Journal of Pharmacology
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• v.18 no.2
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• pp.89-102
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• 1982

The $Na^+-and\;K^+-induced\;Ca^{++}$ release was measured isotopically by millipore filter technique in pig heart mitochondria. With EGTA-quenching technique, the characteristics of mitochondrial $Ca^{++}-pool$ and the sources of $Ca^{++}$ released from mitochondria by $Na^+\;or\;K^+$ were analyzed. The mitochondrial $Ca^{++}-pool$ could be distinctly divided into two components: internal and external ones which were represented either by uptake through inner membrane, or by energy independent passive binding to external surface of mitochondria, respectively. In energized mitochondria, a large portion of $Ca^{++}$was transported into internal pool with little external binding, while in de-enerigzed state, a large portion of transported $Ca^{++}$ existed in the external pool with limited amount of $Ca^{++}$ in the internal pool which was possibly transported through the $Ca^{++}-carrier$ present in the inner membrane. $Na^+$ induced the $Ca^{++}$ release from both internal pool and external pool and external binding pool of mitochondria. In contrast, $K^+$ did not affect $Ca^{++}$ of the internal pool, but, displaced $Ca^{++}$ bound to external surface of the mitochondria. When the $Ca^{++}-reuptake$ was blocked by EGTA, the $Ca^{++}$ release from the internal pool by $Na^+$ was rapid; the rate of $Ca^{++}-efflux$ appeared to be a function of $[Na^+]^2$ and about 8mM $Na^+$ was required to elicit half-maximal velocity of $Ca^{++}-efflux$. So it was revealed that $Ca^{++}-efflux$ velocity was particulary sensitive to small changes of the $Na^+$ concentration in physiological range. Energy independent $Ca^{++}-binding$ sites of mitochondrial external surface showed unique characteristics. The total number of external $Ca^{++}-binding$ sites of pig heart mitochondria was 29 nmoles per mg protein and the dissociation constant(Kd) was $34{\mu}M$. The $Ca^{++}-binding$ to the external sites seemed to be competitively inhibited by $Na^+\;and\;K^+$; the inhibition constant(Ki) were 9.7 mM and 7.1 mM respectively. Considering the intracellular ion concentrations and large proportion of $Ca^{++}$ uptake in energized mitochondria, the external $Ca^{++}-binding$ pool of the mitochondria did not seem to play a significant role on the regulation of intracellular free $Ca^{++}$ concentration. From this experiment, it was suggested that a small change of intracellular free $Na^+$ concentration might play a role on regulation of free $Ca^{++}$ concentration in cardiac cell by influencing $Ca^{++}-efflux$ from the internal pool of mitochondria.

• Progress in Medical Physics
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• v.33 no.4
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• pp.129-135
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• 2022

Purpose: A full-energy-peak (FEP) efficiency correction is required through a Monte Carlo simulation for accurate radioactivity measurement, considering the geometrical characteristics of the detector and the sample. However, a relative deviation (RD) occurs between the measurement and calculation efficiencies when modeling using the data provided by the manufacturers due to the randomly generated dead layer. This study aims to optimize the structure of the detector by determining the dead layer thickness based on Monte Carlo simulation. Methods: The high-purity germanium (HPGe) detector used in this study was a coaxial p-type GC2518 model, and a certified reference material (CRM) was used to measure the FEP efficiency. Using the MC N-Particle Transport Code (MCNP) code, the FEP efficiency was calculated by increasing the thickness of the outer and inner dead layer in proportion to the thickness of the electrode. Results: As the thickness of the outer and inner dead layer increased by 0.1 mm and 0.1 ㎛, the efficiency difference decreased by 2.43% on average up to 1.0 mm and 1.0 ㎛ and increased by 1.86% thereafter. Therefore, the structure of the detector was optimized by determining 1.0 mm and 1.0 ㎛ as thickness of the dead layer. Conclusions: The effect of the dead layer on the FEP efficiency was evaluated, and an excellent agreement between the measured and calculated efficiencies was confirmed with RDs of less than 4%. It suggests that the optimized HPGe detector can be used to measure the accurate radioactivity using in dismantling and disposing medical linear accelerators.

• Korean Journal of Community Nutrition
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• v.12 no.3
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• pp.223-234
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• 2007

This study was done to determine the trans fatty acid (tFA) composition of human milk from postpartum to sixth months after delivery, to investigate the tFA intake of lactating women, and to estimate the intakes of tFA by infants exclusively fed breast milk. A total of 27 lactating Korean women participated to this study voluntarily, gave their breast milk, and responded to an investigation of their diets. The lactating women consumed 2.3-2.8 g/d of tFAs over the period of the first, second, third, and sixth months postpartum, which was 3.4-4.9% of the total fat intake and 0.8%-1.2% of the total energy intake. The proportions of tFAs in the breast milk were 1.89% in colostrum, 1.78% in transitional milk, and 1.78-2.25 in mature milk of the first, second, third, and sixth months postpartum. The tFAs of the breast milk identified in this study were C16:1n9t, C18:1n9t, C18:2n6t12t, C18:2n6t12c, C18:2n6t12t and C18:2n6t11t. Among them, C18:1n9t was predominant, which made up 59.26% of all tFAs in cob strum, 62.36% in transitional milk, and 64.42% in mature milk. The proportion of total tFA was unchanged with time, although some significant differences were noted for individual tFAs. The percentages of C18:2n6t12c and C18:2n6c12t decreased over the study period. Estimated tFA intake of the exclusively breast-fed infants was 0.18 g/d when fed colostrum, 0.29 g/d when fed transitional milk, and 0.53 g/d when fed mature milk until the sixth month of postpartum. Those were 0.5%, 0.8%, and 1.1% of the total energy intake. The results in this study indicate that lactating Korean women consume not a large quantity of tFAs, secrete breast milk not containing much tFA, and the estimated intake of tFAs by infants fed exclusively breast milk is not great.

• Journal of Community Nutrition
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• v.5 no.2
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• pp.105-111
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• 2003

Balanced intake of appropriate nutrients is the key to sustaining and promoting health as well as preventing and treating diseases. It is not always easy, however, to take balanced nutrition and various related factors must be taken into consideration. This report provides a summary of studies that have examined the nutrient intakes of Japanese middle-aged men and the relationship of this intake to drinking, job-related separation from families, and health practices. The alcohol consumption of Japanese middle-aged men has more than tripled in the last forty years. When nutrient intake was examined in relation to alcohol consumption, it was discovered that the maximum acceptable alcohol consumption was approximately 23 grams (about two drinks) of pure alcohol, provided the level of nutrient intake for drinkers was equal to that of non-drinkers. The alcohol energy ratio was approximately 5％. It was also discovered that middle-aged men's eating habits deteriorate when they relocate to new posts without their families and live by themselves. Compared to those living with their families, a higher proportion of those living alone have unfavorable eating habits including skipping breakfast or lunch, having a late lunch, and eating and drinking after dinner until bedtime. When Breslow's seven health practices, nutrient intake, and consumption weight by food group were examined, it was discovered that the group that had many beneficial eating and living habits consumed plenty of legume, pulses, fruit, green yellow vegetables and milk products. Their intake of vitamins and minerals was high and the results of a physical examination proved to be excellent. According to nutrition surveys conducted in Japan, China, the United Kingdom and the United States using a 24-hour recall method with common protocols and strict controls to ensure high levels of accuracy and cross-study validity, the Japanese had the highest cholesterol intake and the lowest dietary fiber intake among the four countries. Also, the alcohol energy ratio of the Japanese exceeded 8％, the highest among the four countries, while their intake of magnesium and iron was the lowest These results indicate that it is necessary to enhance nutritional education for middle-aged men and to reinforce the social environments in which they live and work in order to promote proper diet and nutrition in Japan. (J Community Nutrition 5(2) : 105-111, 2003)

• Korean Journal of Community Nutrition
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• v.23 no.2
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• pp.116-127
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• 2018

Objectives: The purpose of this study was to examine the coverage of the current mandatory nutrition labeling system on the nutrient intake of Koreans. Methods: KNHANES dietary intake data (2013) of 7,242 subjects were used in the analysis. KNHANES dietary intake data were collected by a 24-hour recall method by trained dietitians. For analysis, all food items consumed by the subjects were classified into two groups (foods with mandatory labeling and other foods). In the next step, all food items were reclassified into four groups according to the food type and nutrition labeling regulations: raw material food, processed food of raw material characteristics, processed foods without mandatory labeling, and processed foods with mandatory labeling. The intake of energy and five nutrients (carbohydrate, protein, fat, saturated fat, and sodium) of subjects from each food group were analyzed to determine the coverage of the mandatory nutrition labeling system among the total nutrient intake of Koreans. Results: The average intake of foods with mandatory labeling were 384g/day, which was approximately one quarter of the total daily food intake (1,544 g/day). The proportion of energy and five nutrients intake from foods with mandatory labeling was 18.1%~47.4%. The average food intake from the 4 food groups were 745 g/day (48.3%) for the raw food materials, 54 g/day (3.5%) for the processed food of raw material characteristics, 391 g/day (25.3%) for the processed foods without mandatory labeling, and 354 g/day (22.9%) for the processed foods with mandatory labeling. Conclusions: Although nutrition labeling is a useful tool for providing nutritional information to consumers, the coverage of current mandatory nutrition labeling system on daily nutrient intake of the Korean population is not high. To encourage informed choices and improve healthy eating habits of the Korean population, the nutrition labeling system should be expanded to include more food items and foodservice menus.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.3
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• pp.68-84
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• 2020

This study analyzed the relationship between spatial characteristics and heat waves in the distribution area of the elderly population in Changwon, Gyeongsangnam-do. For analysis, the Statistics Census data, the Ministry of Environment land cover, Landsat 8 surface temperature, and the Meteorological Agency's heat wave days data were used. The spatial characteristics of the distribution of the elderly population was classified into 5 types through K-mean cluster analysis considering the land use types. The characteristics of the elderly population by spatial type were higher in the urbanized type(cluster-3), but the proportion of the elderly population was higher in the agricultural and forest area types(cluster-1, cluster-2). In the characteristics of the surface temperature and the heat wave days, the surface temperature was the highest in the urban area, but heat wave days were the highest in the rural area. As a result of analyzing the heat wave characteristics according to the spatial type of the distribution area of elderly population, cluster-2 with the largest area in agricultural areas was highest at 15.95 days, and cluster-3 with a large area in urbanized types was the lowest at 9.41 days and 9.18 days. In other words, the elderly population living in rural areas is more exposed to heat waves than the elderly population living in urban areas, and the damage is expected to increase. The results of this study could be used as basic data to prepare various policy measures for effective management and prevention of vulnerable areas in summer.

• Korean Journal of Community Nutrition
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• v.14 no.5
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• pp.495-508
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• 2009

The purpose of this study was to evaluate the eating behaviors and dietary quality of various aged adults. This study conducted through questionnaire and dietary survey by 24-hr recall to 850 adults residing in Samcheok. Subjects were divided into four groups according to the age in male and female, which included 20~29 yrs group (male n = 94, female n = 66), 30~49 yrs group (male n = 201, female n = 216), 50~64 yrs group (male n = 88, female n = 96), and $\geq65$ yrs group (n = 46, female n = 43). In male, 20~29 yrs group had a larger proportion of subjects who skipped breakfast, lunch and dinner compared to other groups (p < 0.001, p < 0.05, p < 0.01). The daily food and energy intakes in $\geq50$ yrs group were significantly lower than those of < 50 yrs. Protein and fat intakes of 20~29 yrs group were significantly higher than those of the other groups. But ND (Nutrient Density) of minerals as like calcium, iron and plant iron in 20~29 yrs group were significantly lower than those of other groups. The KDDS (Korean's Dietary Diversity Score) of 20~29 yrs group, 30~49 yrs group, 50~64 yrs group and $\geq65$ yrs group in male were 4.1, 3.8, 3.7 and 3.5 respectively and there was significant difference (p < 0.001). In female, skipping breakfast and dinner were significantly higher in 20~29 yrs group than in other groups (p < 0.001, p < 0.001). And the use of nutrient supplementation was higher in 30~49 yrs group than that of other groups (p < 0.05). The daily energy intakes was higher in 20~49 yrs group than that of $\geq65$ yrs group. The ND (Nutrient Density) of animal protein, vitamins A and $B_1$ in 20~29 yrs group were significantly lower than those of other groups. The KDDS of 20~29 yrs group, 30~49 yrs group, 50~64 yrs group and $\geq65$ yrs group in female were 4.0, 3.9, 3.9 and 3.6 respectively and $\geq65$ yrs group was significant lower than other groups. According to these results, $\geq65$ yrs and 20~29 yrs group had more dietary habit problems and poor nutrition status than 30~64 yrs group. The results of this study revealed that nutritional management and education for adequate meals should be emphasized in adults and elderly.

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.484-494
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• 2014

The purpose of this study was to evaluate dietary intake according to the risk of coronary heart disease (less than 10% = low-risk group; 10~20% = middle-risk group) based on Framingham risk score (FRS), on 122 male adult subjects. The body weight and body mass index were not significantly different between the groups, while height of the low-risk group was shown to be significantly high compared to that of the middle-risk group. The daily energy intake was shown to be significantly high in the low-risk group with 1,910.88 kcal, compared to 1,606.63 kcal of the middle-risk group. As a result of analyzing nutrient intake per 1,000 kcal of energy, while the low-risk group had significantly high intake of animal protein, fat, and animal fat compared to the middle-risk group, the intake of plant protein, carbohydrate, and plant iron was found to be significantly low. The daily food intake was shown to be significantly high in the low-risk group (1,445.16 g), compared to the middle-risk group (1,075.12 g). The low-risk group was found to have significantly high intake of sugars, eggs, and beverages compared to the middle-risk group, while mushrooms intake was significantly high in the middle-risk group. Dietary variety score (DVS) was significantly high in the low-risk group with 26.42, compared to 22.66 of the middle-risk group. Dietary diversity score (DDS) was indicated to be significantly high in the low-risk group with 3.70, compared to 3.27 of the middle-risk group. The low-risk group was indicated to have significantly high score in DDS of dairy products and fruit group, compared to the middle-risk group. In the correlation between diversity index of food intake (DVS and DDS) and FRS, DDS was shown to have significantly negatively correlation with FRS after adjusting for confounding factors. To sum up these results, the adult males with low-risk of coronary heart disease had more various consumptions of fruits and milk, compared to the subjects with the middle-risk. The proportion of consuming major food groups such as cereals, meat group, milk, fruits, and vegetables more than a fixed quantity was indicated to be high. Accordingly, dietary habit for intake of various food seems to be necessary, to prevent coronary heart disease.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.346-353
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• 2011

Base hydrolysis of 7-hydroxy-2H-chromen-2-one (HC) and 7-hydroxy-2H-chromen-2-one-4-acetic acid (HCA) in aqueous-methanol and aqueous-acetone mixtures were studied kinetically at temperature range from 283 to 313 K. The activation parameters of the reactions were evaluated and discussed. Moreover, the change in the activation energy barrier of the investigated compounds from water to water-methanol and water-acetone mixtures was estimated from the kinetic data. It is observed that the change in activation barriers is more or less the same for the hydrolysis of HC and HCA. Base hydrolysis of HC and HCA follows a rate law with $k_{obs}=k_2[OH^-]$. The decrease in the rate constants of HC and HCA as the proportion of methanol or acetone increases is due to the destabilization of $OH^-$ ion. The high negative values of entropy of activation support the proposal mechanism, i.e. the investigated reaction takes place via the formation of an intermediate complex. Moreover, these values refer to the rigidity and stability of the intermediate complex. Thus, the ring opening of the intermediate complex would be the rate controlling step.