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Comparative study on the health and dietary habits of Korean male and female adults before and after the coronavirus disease 2019 pandemic: utilizing data from the 8th Korea National Health and Nutrition Examination Survey (2019-2021) (COVID-19 팬데믹 전후 한국 성인 남녀의 건강 및 식생활행태 비교연구: 국민건강영양조사 제8기(2019-2021년도) 자료 활용)

  • Chaemin Kim;Eunjung Kim
    • Korean Journal of Community Nutrition
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    • v.29 no.1
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    • pp.65-80
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    • 2024
  • Objectives: This study aims to compare changes in physical factors, health behaviors, eating habits, and nutritional intake among Korean male and female adults over a period of three years (2019-2021) before and after the outbreak of coronavirus disease 2019 (COVID-19). Methods: This study utilized raw data from the 8th Korea National Health and Nutrition Examination Survey (2019-2021). The participants in this study included 6,235 individuals in 2019, 5,865 individuals in 2020, and 5,635 individuals in 2021. Individuals whose daily energy intake was less than 500 kcal or exceeded 5,000 kcal were excluded from the study. Results: In comparison to 2019, overweight/obesity rates, weight, waist circumference, weekend sleep hours, and resistance exercise days/week increased in both male and female during the COVID-19 pandemic. Regarding eating habits, the proportions of people skipping breakfast, not eating out, consuming health supplements, and recognizing nutritional labels increased in 2020 and 2021, whereas the rate of skipping dinner decreased. Total energy intake has continued to decrease for the two years since 2019. A comparison of nutrient intake per 1,000 kcal before and after the outbreak of COVID-19 revealed that intake of nutrients, including protein, phosphorus, iron, vitamin A, riboflavin, and niacin increased, while folic acid intake decreased. In male, calcium, phosphorus, riboflavin, and niacin intakes increased, whereas iron, vitamin C, and folic acid intakes decreased. In female, phosphorus, iron, vitamin A, and riboflavin intake increased significantly, while protein and niacin intake decreased significantly. Conclusions: After COVID-19, the obesity rate, breakfast skipping rate, health supplement intake, and nutritional label use increased, while the frequency of eating out, dinner skipping rate, and total energy intake decreased. These environmental changes and social factors highlight the need for nutritional education and management to ensure proper nutritional intake and reduce obesity rates in the post-COVID-19 era.

Study Design and Baseline Results in a Cohort Study to Identify Predictors for the Clinical Progression to Mild Cognitive Impairment or Dementia From Subjective Cognitive Decline (CoSCo) Study

  • SeongHee Ho;Yun Jeong Hong;Jee Hyang Jeong;Kee Hyung Park;SangYun Kim;Min Jeong Wang;Seong Hye Choi;SeungHyun Han;Dong Won Yang
    • Dementia and Neurocognitive Disorders
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    • v.21 no.4
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    • pp.147-161
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    • 2022
  • Background and Purpose: Subjective cognitive decline (SCD) refers to the self-perception of cognitive decline with normal performance on objective neuropsychological tests. SCD, which is the first help-seeking stage and the last stage before the clinical disease stage, can be considered to be the most appropriate time for prevention and treatment. This study aimed to compare characteristics between the amyloid positive and amyloid negative groups of SCD patients. Methods: A cohort study to identify predictors for the clinical progression to mild cognitive impairment (MCI) or dementia from subjective cognitive decline (CoSCo) study is a multicenter, prospective observational study conducted in the Republic of Korea. In total, 120 people aged 60 years or above who presented with a complaint of persistent cognitive decline were selected, and various risk factors were measured among these participants. Continuous variables were analyzed using the Wilcoxon rank-sum test, and categorical variables were analyzed using the χ2 test or Fisher's exact test. Logistic regression models were used to assess the predictors of amyloid positivity. Results: The multivariate logistic regression model indicated that amyloid positivity on PET was related to a lack of hypertension, atrophy of the left temporal lateral and entorhinal cortex, low body mass index, low waist circumference, less body and visceral fat, fast gait speed, and the presence of the apolipoprotein E ε4 allele in amnestic SCD patients. Conclusions: The CoSCo study is still in progress, and the authors aim to identify the risk factors that are related to the progression of MCI or dementia in amnestic SCD patients through a two-year follow-up longitudinal study.

A Study on Nutritional Status of Young Children in Rural Korea (농촌영유아의 영양상태(營養狀態)에 관(關)한 조사연구(調査硏究))

  • Kim, Kyoung-Sik;Kim, Pang-Ji;Nam, Sang-Ok;Choi, Jung-Shin
    • Journal of Preventive Medicine and Public Health
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    • v.7 no.1
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    • pp.1-28
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    • 1974
  • The writers have conducted the investigation to assess the nutritional status of young rural Korean children aged from 0 to 4 years old in August 1971. The survey areas were Kaejong-myon. Daeya-myon, Okku-gun, Jeonra-bukdo, Korea. These survey areas were typical agricultural plain areas. The total numbers of children examined were 2,706 comprising 1,394 male and 1,312 female. The weight, height, and chest circumference of children were measured and means and standard deviations. were calculated for each measurement. In addition, the nutritional status of each child was classified by the four levels of malnutrition and the Gomez classification, The examination of red blood cell count, haematocrit value, and intestinal parasite infection were carried out at the same time. In general, recent work tend to suggest that environmental influences, especially nutrition, are of great importance than genetic background or other biological factors for physical growth and development. Certainly the physical dimensions of the body are much influenced by nutrition, particularly in the rapidly growing period of early childhood. Selected body measurements can therefore give valuable information concerning protein-calory malnutrition. Growth can also be affected by bacterial, viral, and parasitic infection. For the field workers in a developing country, therefore, nutritional anthropometry appears to be of greatest value in the assessment of growth failure and undernutrition, principally from lack of protein and calories. In order to compare and evaluate the data obtained, the optimal data of growth from the off-spring of the true well-fed, medically and socially protected are needed. So-called 'Standards' that have been compiled for preschool children in Korea, however, are based on measurement of children from middle or lower socio-economic groups, who are, in fact, usually undernourished from six months of age onwards and continuously exposed to a succession of infective and parasitic diseases. So that, the Harvard Standards which is one of the international reference standards was used as the reference standards in this study. Findings of the survey were as follows: A. Anthropometric data: 1) Comparing the mean values for body weight obtained with the Korean standard weight of the same age, the rural Korean children were slightly haevier than the Korean standard values in both sexes. Comparing with the Japanese children values, the rural Korean children were slightly haevier in male and in the infant period of female but lighter in female of the period of 1 to 4 years old than Japanese children. 2) Comparing the mean values for height obtained with the Korean standard height of the same age, the rural Korean children were taller than the Korean standard values except the second half of infatn period in both sexes. Comparing with the Japanese children, the rural Korean children were slightly smaller than Japanese children except the first half of infant peroid in both sexes. 3) Mear values of chest circumference of rural Korean children obtained were less than the Korean standard values of the same ages in both sexes. B. Prevalence of Protein-Calory Malnutrition: Children examined were devided into two groups, i. e., infant(up to the first birthday) and toddler (1 to 4 fears old). 1) Percentages of four levels of malnutrition: a) When the nutrtional status of each child was classified (1) by body weight value, the percentages for male and female of children attained standard growth were 52.8%(infant 83.3%, toddler 44.4%) and 39.7% (infant 74.5%. toddler 30.5%), the first level of malnutrition were 31.9%(infant 13.7%, toddler 36.9%) and 31.7%(infant 15.3%, toddler 36,0%), the second level of malnutrition were 12.3%(infant 1.7%, toddler 15.3%) and 23.3% (infant 7.7%, fodder 27.5%), the third level of malnutrition were 2.7%(infant 0.7%, toddler 3.2%) and 4.6%(infant 1.8%, toddler 5.3%) the fourth level of malnutrition were 0.3% (infant 0.7%, toddler 0.2%) and 0.7% (0.7% for infant and toddler) respectively. (2) by height value, the percentages for male and female of children attained standard growth were 80.3% (infant 97.3%, toddler 75.6%) and 75.1% (infant 96.4%, toddler 69.5), the first level of malnutrition were 17.9% (infant 2.0%, toddler 22.3%) and 23.6% (infants 3.6%, toddler 28.8%), the second level of malnutrition were 1.2% (infant 0.3%, toddler 1.5%) and 1.1% (infant 0%, toddler 1.4%), the third level of malnutrition were 0.4%(infant 0.3%, toddler 0.5%) and 0.2%(infant 0%, toddler 0.3%), the fourth level of malnutrition were 0.1%(infant 0%, toddler 0.1%) and 0% respectively. (3) by body weight in relation to height, the percentages for male and female of children attained standard growth were 87.9% (infant 77.6%, toddler 87.9%) and 78.2% (infant 77.4%, toddler 78.2%), the first level of malnutrition were 12.2% (infant 18.4%, toddler 10.6%) and 18.2% (infant 17.9%, toddler 18.3%), the second level of malnutrition were 1.9%(infant 3.3%, toddler 1.5%) and 3.0%(infant 3.3%, toddler 2.9%), the third level of malnutrition were 0.1%(infant 0%. toddler 0.1%) and 0.5% (infant 0%, toddler 0.6%), the fourth level of malnutrition were 0.1%(infant 0.7%, toddler 0%) and 0.3% (infant 1.5%, toddler 0%) respectively. b) When the nutritional status of each child according to the mother's age at perturition, i. e., young aged mother (up to 30 years old), middle aged mother (31 to 40 years old) and old aged mother (41 years or above) was classified (1) by body weight, among infants and toddlers, at each year of age, with increasing the mother's age, there was an increase in percentage of subjects underweight. This tendency of increasing percentage of underweight was more significant in the infant period than the toddler period. (2) by height value, no significant differences between each mother's age group were found. c) When the nutritional status of each child according to the birth rank, i. e., lower birth rank (first to third) and higher birth rank (fourth or above) was classified (1) by weight value, children of higher birth rank were slightly more often underweight than those of lower birth rank, but not significant. (2) by height value, no differences were found between children of lower and higher birth rank. 2) Gomez Classification: When the nutritional status of each child was classified a) by body weight value, the percentages for male and female of children. attained standard growth were 53.1% (infant 82.6%, toddler 44.9%) and 39.2% (infant 73.4%, toddler 30.1%), the first degree of malnutrition were 39.4% (infant 14.7%, toddler 46.2%) and 47.1% (infant 21.9%, toddler 53.8%), the second degree of malnutrition were 7.3%(infant 2.3%, toddler 8.6%) and 12.9% (infant 4.0%, toddler 15.2%). and the third degree of malnutrition were 0.2%. (infant 0.3%, toddler 0.2%) and 0.8% (infant 0.7%, toddler 0.9%) respectively. b) by height value, the percentages for male and female of children attained standard growth were 80.8% (infant 97.0%, toddler 76.3%) and 73.8%(infant 95.6%, toddler 68.0%), the first degree of malnutrition were 18.5% (infant 2.7%, toddler 22.9%) and 24.6% (infant 4.4%, toddler 30.0%), the second degree of malnutrition were 0.6%(infant 0.3%, toddler 0.7%) and 0.5% (infant 0.1%, toddler 0.7%), and the third degree of malnutrition were 0.1%(infant 0%, toddler 0.1%) and 1.1% (infant 0%, toddler 1.3%) respectively. C. Results of clinical laboratory examination: 1) Red blood cells: The ranges of mean red blood cell counts for male and female were $3,538,000/mm^3\;to\;4,403,000/mm^3\;and\;3,576,000/mm^3\;to\;4,483,000/mm^3$ respectively. The lowest red cell counts were seen at the age of 0-3 months for male and 1-2 months for female. 2) Haematocrit value : The ranges of haematocrit value of male and female were 35.1% to 38.8% and 34.7% to 38.8% respectively. The lowest haematocrit values were seen at the age of 2-3 months for male and 1-2, months for female. 3) The prevalence rates of intestinal parasites for male and female children with Ascaris lumbricoides were 34.1% (infant 18.8%, toddler 38.1%) and 36.0%(infant 18.4%, toddler 40.7%), with Trichocephalus trichiuris were 6.8% (infant 2.9%, toddler 7.9%) and 9.0% (infant 3.0%, toddler 10.6%), with Hookworm were 0.3% (infant 0.5%, toddler 0.2%) and 0.3% (infant 0.5%, toddler 0.3%), with Clonorchis sinensis were 0.4%(infant 0%, toddler 0.5%) and 0.1%(infant 0%, toddler 0.1%) respectively.

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The influence of some intrauterine growth variables on neonatal blood pressure (태아기 자궁내 성장지표와 신생아 혈압과의 관련성)

  • Min, Jungwon;Park, Eun Ae;Kong, Kyoungae;Park, Bohyun;Hong, Juhee;Kim, Young Ju;Lee, Hwayoung;Ha, EunHee;Park, Hyesook
    • Clinical and Experimental Pediatrics
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    • v.49 no.9
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    • pp.966-971
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    • 2006
  • Purpose : 'Programming' describes the process that stimulus at a critical period of development has lifelong effects. The fact that low birth weight links to the risk of elevated blood pressures in adult life is well known. This study aims to examine whether this link is evident in the newborn by investigating the relationship of the intrauterine growth indices and neonatal blood pressure(BP). Methods : We studied 127 neonates who were born at Ewha Womans' Hospital and their mothers enrolled our cohort study during pregnancy. Data on the mothers and details of the birth records were tracked and collected from medical charts. Neonatal BP was measured within 24 hours after birth. Results : Neonatal SBP was positively correlated to intrauterine growth indices; birth weight(BW)(r=0.4), head circumference(HC)(r=0.4), and birth height(r=0.3). However, an inverse relationship existed, between HC/BW ratio and neonatal SBP(r=-0.4). After adjusting for the baby's sex, maternal BP, and gestational age, neonatal SBP still associated with intrauterine growth indices. SBP was 7 mmHg higher in the highest BW group(${\geq}90percentiles$) compared to the lowest group(<10 percentiles). On the other hand, SBP was 17 mmHg lower in the highest HC/BW group(${\geq}90percentiles$) compared in the lowest group(<10 percentiles). Conclusion : This study could not find the evidence that intrauterine growth retardation affect on elevated neonatal BP. It suggests that the initiating events of BP programming may occur during postnatal growth period. To identify the critical starting period that intrauterine growth retardation leads to elevated BP, a study tracking BP changes from birth to childhood is required.

Association between antioxidant vitamin intake and obesity among Korean women: using the Korea National Health and Nutrition Examination Survey 2007 ~ 2016 (우리나라 성인 여성의 항산화비타민 섭취량과 비만의 연관성 : 2007 ~ 2016년 국민 건강영양조사 자료를 이용하여)

  • Ham, Dongwoo;Kim, Seong-Ah;Jun, Shinyoung;Kang, Min-Sook;Joung, Hyojee
    • Journal of Nutrition and Health
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    • v.51 no.5
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    • pp.400-413
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    • 2018
  • Purpose: This study examined the association between the antioxidant vitamin intake and obesity in Korean women. Methods: Adult women aged ${\geq}19years$ who completed a health examination and nutrition survey from the Korea National Health and Nutrition Examination Survey between 2007 ~ 2016 were selected for the study (n = 30,425). A BMI ${\geq}25kg/m^2$ and waist circumference ${\geq}85cm$ were defined as obesity and abdominal obesity, respectively. The individual antioxidant vitamin intake was estimated by linking the antioxidant vitamin composition database of commonly consumed foods and the subjects' 24-hour recall food consumption data. Carotenoids, retinol, vitamin A (retinol activity equivalent), vitamin C, tocopherols, and vitamin E (${\alpha}$-tocopherol equivalent) were included in the analysis. Each vitamin intake was converted to the nutrient density per 1,000 kcal. Odds ratio (ORs) and 95% confidence interval (CI) for obesity according to each tertile of the nutrient density was obtained from multiple logistic regression adjusted for age, household income, education level, smoking, alcohol consumption, and physical activity. Results: The mean intake of ${\alpha}$-carotene, retinol, vitamin E, ${\alpha}$-tocopherol, and ${\gamma}$-tocopherol per 1,000 kcal was significantly lower in the obese group than in the normal group. A higher intake of lycopene was inversely associated with obesity (highest vs. lowest; OR = 0.89, 95% CI: 0.83-0.96) and abdominal obesity (highest vs. lowest; OR = 0.88, 95% CI: 0.81-0.95). Higher intakes of ${\alpha}$-carotene, total carotenoids, vitamin A, and ${\gamma}$-tocopherol also had a negative relationship with abdominal obesity. The antioxidant vitamin intakes from eggs, milk and dairy products, seasoning, and grains were significantly lower in the obese group than in the normal group. Conclusion: This study showed that the dietary intake of antioxidant vitamins was inversely associated with obesity and abdominal obesity among Korean women. Further study will be needed to examine the causal relationship between the antioxidant vitamin and obesity.

Effects of Diet Food Containing Jerusalem Artichoke's Inulin, Lotus Leaf, and Herb on Weight and Body Fat of Obesity University Students (돼지감자의 이놀린, 연잎, 허브의 다이어트제제가 비만인의 체중 및 체성분에 미치는 영향)

  • Lee, Eun-Hye;Kang, Sang-Mo
    • Journal of Applied Biological Chemistry
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    • v.52 no.1
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    • pp.8-14
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    • 2009
  • This study was conducted to assess the effects of diet food containing Jerusalem artichoke's inulin, lotus leaf, and herb on weight and body fat. Participants in this study were selected based on the following criteria: BMI over $25kg/m^2$, body fat percentage higher than 25%, abdominal obesity level of 0.85 measured by body composition measurement unit (ZEUS 9.9 PLUS, Korea) total 24 female and male university students over 20 of age were assigned to two different groups: control group and diet group and the study was carried out for 30 days. When we measured what the tester's body weight and height, we used an automatic measure machin which is called IMI-1000 from Immanuel company and when we measured what the hip and wist circumference, we used a tape measure. When we measured body mss index (BMI), body Int, body mass, lean mass, waist/hip ratio (WHB), obesity index, we used a ZEUS9.9 PLUS-Korea which is based on bioelectrical impedance analysis, The food intake was checked by means of diet record method to be input into CAN program in order to analyze nutrient intake. Our findings indicated that the diet group, as compared to the control group, lost weight of approximately 2.5 kg and showed statistically significant difference. In addition the level of body Int, muscle, abdominal obesity, obesity, waist and bottom measurement all showed significant decrease after study period. However, there was no big difference in body fat percentage because both body fat level and muscle level dropped together, Putting all these together, diet food in this study containing Jerusalem artichoke's inulin, lotus leaf powder, and herbs powder including nettle, eucalyptus was found to be effective in significant reduction of weight and body fat and obesity-related body indicators. Also, it is considered that this diet food has potential to prevent and improve effectively obesity from abnormal fat accumulation.

Osteoid Osteoma Around the Hip Joint (고관절 주위에 발생한 유골 골종)

  • Kim, Tai-Seung;Kim, Jong-Heon;Lee, Bong-Gun;Kim, Soon-Myung
    • The Journal of the Korean bone and joint tumor society
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    • v.11 no.2
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    • pp.168-174
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    • 2005
  • Purpose: We experienced 8 cases of osteoid osteoma arising around hip joint which had some characteristics that differ from those arising on long bone. we reports the characteristics of osteoid osteoma arising around the hip joint. Materials and Methods: 8 cases of osteoid osteoma were diagnosed during 1985 to 2004 at hanyang university hospital. all cases were comfirmed patholgically. 6 cases were male, 2 cases were female patients. The mean age was 17 years old (ranged from 8 to 29). They occurred in intertrochanteric area (4 cases), subtrochanteric area (2 cases), acetabulum (1 case) and femoral neck (1 case). We used radiologic tools including magnetic resonance image, computed tomography, bone scintigraphy. clinicopathologic test including erythrocyte sedimentation rate and Creactive protein. Results: The patients expressed various symptoms including thigh pain, knee pain, low back pain and radiating pain respectively. 2 patients had experienced operation on knee joint. 3 patients showed limping gait. Aspirin relieved the pain in 3 patients. The difference in circumference was 1cm between both thighs in 2 cases. Conclusion: Patients with osteoid osteoma arising around hip joint which have various symptoms such as severe knee pain and claudication, differ from infectious disease by clinicopathologic test including erythrocyte sedimentation rate and C- reactive protein and had better diagnostic result in computed tomography.

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Effects of Laminaria Japonica Extract Supplement on Blood Glucose, Serum Lipids and Antioxidant Systems in Type ll Diabetic Patients (다시마추출물이 제2형 당뇨병 환자의 혈당, 지질 및 항산화 체계에 미치는 영향)

  • Park, Min-Jung;Ryu, Ho-Kyung;Han, Ji-Sook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.11
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    • pp.1391-1398
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    • 2007
  • We performed a randomized double-blind placebo-controlled trial to determine whether Laminaria japonica extract (LJE) supplement modulates blood glucose, serum lipids and antioxidant systems in type II diabetic patients. We also measured critical parameters assessing safety in liver and kidney functions after LJE supplement. A total of 37 patients (18 males and 19 females) were randomized to either LJE group or placebo group. The treatment group received four 350 mg of LJE capsules (1.4 g, total) per day for 12 weeks. The placebo group received the same dose of cellulose capsules. Baseline characteristics regarding general life style and dietary intake pattern were similar between the two groups. There were no significant influences of LJE supplement except for waist circumference on anthropometric parameters. As the whole, 12 weeks of LJE supplement resulted in a little decrease in fasting blood glucose (FBG) and glycated hemoglobin (HbA1c), but a significant decrease was not observed. Total cholesterol, LDL-cholesterol and triglyceride concentrations were significantly (p<0.05) lowered in LJE group. The antioxidant enzymes, glutathion peroxidase (GSH-px) and superoxide dismutase (SOD) levels were elevated in the LJE group (p<0.05) compared to the placebo. The increase of these enzymes was associated significantly with the decrease of MDA concentration (p<0.05). Furthermore, LJE supplement showed no adverse effects on the functions of liver and kidney. Findings from this study suggest that LJE supplement can help improve serum lipid status in type II diabetic subjects without adverse effects.

The Influence of Breakfast Size to Metabolic Risk Factors (아침식사량이 대사위험요인에 미치는 영향)

  • Kim, Yun-Jin;Lee, Jeong-Gyu;Yi, Yu-Hyeon;Lee, Sang-Yeoup;Jung, Dong-Wook;Park, Seon-Ki;Cho, Young-Hye
    • 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.

Study on the Improvement of Stow Net Fishing Technique and the Enlargement of Fishing Ground to the Distant Waters - 1 . Model Experiment of the Net - (안강망어법의 개량과 어장의 원해로의 확대를 위한 연구 - 1 . 어구의 모형실험 -)

  • Lee, Byoung-Gee;Kim, Jin-Kun;Lee, Ju-Hee
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.24 no.2
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    • pp.55-64
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    • 1988
  • Stow nets have widely been used in the western sea of Korea from the olden age. The original structure of a stow net is a large square-sectional bag net made of 4 netting panels, and the front fringes of top and bottom panels are connected to the top and bottom beams respectively. Wire ropes, which is originated from the holding anchor are gradually forked and biforked, and finally 4 pieces of wire rope (biforked pendants) are jointed to each beam. Much convenience caused by long and heavy beams were problemed, then some studies have been carried out to improve the net since 1930's. The most effective improvement were achieved in 1980 by Mr. Han and his colleagues. The key point of improvement was that the beams were removed and the belt shaped shearing device made by canvas was attached to the side panels, the head rope and ground rope to the front fringe of top and bottom panel, and biforked pendants are joined to the shearing device. Even though this is the epoch-making improvement of a stow net, the further study should be required to find out more effective method. The authors carried out a model experiment on the stow net to determine the vertical and horizontal opening of a net mouth, and also examine the front, top and side-view configuration of the net. The model net was constructed depending on the Similarity Law of Fishing Gear in 1/10 and 1/20 scale and set against to the current at shallow and speedy flowing channel. The vertical and horizontal openings were determined by using scaled bamboo poles, and the configuration was observed by using specially prepared observation platform and underwater observation glass, and also photographed by using specially prepared underwater photographic equipment. The results obtained can be summarized as follows: 1. The opening height and width of the shearing device varied in accordance with the relative length of the biforked pendants. Considering the height and width of shearing device in 6 cases of the arrangement system of biforked pendants, the best result was obtained in the case that the 2nd, 3rd and 4th pendents from the bottom-most was 5%, 9% and 4% longer than that. 2. On the top-view configuration the excessive deformation of head rope and ground rope were observed. In the actual net, 54m long head rope and ground rope were attached to the front fringe of top and bottom panels so that the head rope may be lifted to make the net mouth open highly. But actually the head rope and the ground rope are streamed backward without any lift, and also the netting followed the ropes were deformed until the 2/5 in the whole length of the net. This deformation may be guessed to disturb the entrance of fish school into the net and also caused the net to get caught by obstacles in the sea bed and to be broken largely. 3. Hydrodynamic resistance R of the actual net may be deduced as R(kg)=29.2$\times$103 v1.65. It is also expressed as R(kg)=5.9$\times$d/l$\times$ab v1.65. depending on the formula deduced by Koyama to estimate the resistance of trawl nets, where d/l denote the ratio between diameter of netting twine and length of mesh leg in every part of side panel, a and b, the stretched circumference of the mouth and the stretched length of the net, respectively.

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