Purpose: This study was conducted to examine the status of dietary behavior and its association with study-related factors in middle school students. Methods: Study-related factors, dietary habit score and dietary behaviors were surveyed by questionnaire and then analyzed. A total of 580 students in some middle schools in Gyeonggi-do participated in this study. Collected data were analyzed using SPSS for windows Ver. 22.0. Results: 71.3% of the subjects slept for 6 ~ 8 hours, and the studying time outside of school was the highest (2 ~ 4 hours). The highest score for stress from studying by private lessons or academies was 'seldom stressed', with higher stress being observed in male students than female students. The average dietary habit score was 3.69 in male students and 3.62 in female students. The highest average time for meal eating was 10 ~ 20 minutes, with shorter times being observed for male students than female students. Eating meals was regular in most students and the highest number of snack eating was 1 ~ 2 times a day. For dietary behaviors by study-related factors, students with more than 2 hours of studying time outside of school showed higher dietary habit scores than those with less than 2 hours, who showed significantly higher rates of eating 2 meals a day. As the sleeping hours and daily average studying hours increased, the rate of regular meal eating increased significantly. Conclusion: The students showed good, above average dietary behaviors, but gender differences in study-related factors and dietary behaviors. Moreover, the sleeping hours and the studying time outside of school were correlated with dietary habit scores and dietary behaviors. Thus, continuous and systematic education for proper dietary behavior is needed along with greater interest in students with problems of study-related factors, particularly those due to study burden.
Journal of the Korean Society of Food Science and Nutrition
/
v.31
no.5
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pp.871-876
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2002
This study was conducted to verify the relation between relation between vegetarian diet and the serum lipid levels, blood sugar and blood pressure from October 1996 to February 1997. The vegetarians subjects were 245 Buddhist nuns (age:23~79 yrs) and control subjects consisted of 235 healthy female adults (age: 23~70 yrs) selected from the teachers, the nurses and the housekeepers living in Chinju Gyeongsang Nam-do. The contents included anthropometric measurement, questionnaires about eating behavior score and preference for taste and biochemical characteristics of the blood. The results were summarized as follows. The average duration of vegetarian diet of the vegetarians was 13.1 years. Vegetarians prefer to a pepper, a sweet and a acidic in the right order but that non-vegetarians prefer to a sweet, a acidic and pepper in the right order. Both groups of less than a decade and more than two decade of vegetarian diet prefer to a pepper, sweet, a acidic, a bitter, a salty and a lily, and a 10~20 yr group with vegetarian diet was fond of a pepper, a bitter, a acidic, a sweet, and a oily, in the right order. This seems to be ascribable to a difference in the health knowledge and interest. Vegetarians and non-vegetarians who said that they were fond of salty were 38.8% and 52.8%, medium was 33.9% and 33.6%, and not salty was 27.3% and 13.6%. Eating behavior score of vegetarians and non-vegetarians were 25.1 and 23.1 respectively. Eating behavior scores of vegetarians were significantly higher than those of non-vegetarians (p<0.05). Eating behavior scores of the group with more than a decade of vegetarian diet were significantly higher than those of the group with less than a decade of vegetarian diet. Levels of serum total-cholesterol, LDL-cholesterol, and AI of the salty group were significantly higher (p<0.05) than those of not salty group. Levels of serum triglyceride, HDL-cholesterol, blood sugar had no significant relation with preference of salty. Blood pressure was not related with preference of salty, but that of those who prefer a salty tended to be high. This study also reveals that the preference of a salty was significant influence on serum total-cholesterol, LDL-cholesterol, and AI, but the vegetarians did not prefer salty and have a good eating behavior. Consequently, vegetarian diet can be considerably effective in reducing the level of the risk factors of cardiovascular disease.
The consumption of herbal medicines has been increasing with growing interest in health. However, due to recent climate change and the complex distribution process of herbal medicines with high import dependence the likelihood of contamination with mycotoxin has been increased. Mycotoxins are emerging as key indicators for ensuring safety of herbal medicines. A total of 498 herbal medicine samples were screened for mycotoxin contamination in this study. Aflatoxin in the herbal medicine samples was extracted by using immunoaffinity column, then the extracted aflatoxin was quantified via high performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method. The extraction method was verified by linearity, recovery, LOD and LOQ. Aflatoxins were detected in 39/498 samples in an average of $7.670{\mu}g/kg$ ($0.610-77.452{\mu}g/kg$ range). Although safety standards for Corydalis Tuber is not currently available in korea, five of the 39 samples had high concentration of aflatoxins (average of $14.9{\pm}4.1{\mu}g/kg$). In conclusion, it is urgent to establish safety criteria of aflatoxin in Corydalis Tuber. The results of the current study suggest that continuous monitoring is necessary for proactive management of herbal medicine safety.
Kim, Man Soo;Chang, Kyu Seob;Kim, Soung Rai;Jeon, Byeong Seon
Korean Journal of Agricultural Science
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v.9
no.1
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pp.357-370
/
1982
Recent concern regarding price and availability of fossil fuels has spurred the interest in alternative sources for farm crop drying. Among the available options such as biomass energy, wind power, nuclear energy and solar energy etc., the increasing attention is being directed to the utilization of heat from solar energy especially for farm crop drying. Even though solar energy is dispersed over a large land area and only a relatively small amount of energy can be simply collected, the advantages of solar energy is that the energy is free, non-polluting. The study reported here was designed to help supply the informations for the development of simple and relatively inexpensive solar warehouse for farm crop drying and storage. Specifically, the objectives of this study were to determine the performance of the solar collector fabricated, to compare solar supplemented heat drying with natural air drying and to develop a simulation model of temperature in stored grain, which can be used to study the effects due to changes in ambient air temperature. For those above objectives, solar collector was fabricated from available materials. Corrugated steel galvanized sheet, painted flat black, was used as absorbers and clear 0.2mm polyethylene sheet was the cover material. The warehouse for rough rice drying and storage was constructed with concrete block, and the solar collector was used as the roof of warehouse instead of original roofing system of it. The results obtained in this study were as follows: 1. The thermal efficiency of the solar collector was average 26 percent and the overall heat transfer coefficient of the collector was approximately $25kJ/hr.m^2\;^{\circ}K$. 2. Solar heated air was sufficient to dry one cubic meter of rough rice from 23.5 to 15.0 percent in 7 days and natural air was able to dry the same amount of rough rice from 20.0 to 5 percent in l2 days. 3. Drying with solar heat reduced the required drying time to dry the same amount of rough rice into a half compared to natural air drying, but overdrying problems of the bottom layer were so severe that these problems should be thoroughly analyzed. 4. Simulation model of temperature in stored grain was developed and the results of predicted temperature agreed well with test results. 5. Based on those simulated temperature, changes in the grain-temperature were a large at the points of the wallside and the damage of the grain would be severe at the contact area of wall.
Cha, Seung-Bin;Rayamajhi, Nabin;Lee, Won-Jung;Shin, Min-Kyoung;Roh, Yu-Mi;Jung, Myung-Hwan;Myoung, Kil-Sun;Ahn, Young-Tae;Huh, Chul-Sung;Yoo, Han Sang
Korean Journal of Veterinary Research
/
v.50
no.3
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pp.213-220
/
2010
Salmonella (S.) Enterica infection ranks among the most common food borne bacterial infections worldwide. Although there are six subspecies of S. Enterica, the vast majority of human and animal infections are caused by strains belonging to subspecies 1 serovar Typhimurium and Enteritidis. Recent reports on antibiotic resistance of Salmonella spp. are rising steadily. The increasing problem of antibiotic resistance has rekindled interest in bacteriophage to therapy. Therefore, we investigated the efficacy of bacteriophage in S. enterica serovar Enteritidis infected mice and pigs by measuring of body condition, body weight, bacterial colonization and weight of organs based on the in vitro analysis. In vitro experiment, phage cultured with S. Enteritidis showed clear lysis pattern, the plaque forming unit (PFU) of our phage culture was $1.5{\times}10^{11}PFU/mL$, and phage showed its maximum activity at 4 h post inoculation. In mouse experiment, there was no significant difference among experimental groups in the general body conditions and body weight of mice. However, there was difference in weight of liver and spleen depending on the experimental group (p < 0.05). The weight of liver and spleen were reduced by the phage treatment. Also bacterial colonization in spleen and liver were significantly reduced by the phage treatment. In pig experiment, the general body conditions and body temperature exhibited not much difference among the pigs except few pigs in group 3 which showed poor body conditions. From the feces in each group, we could isolate the S. Enteritidis only from group 3. Bacterial enrichment culture was necessary for isolating the bacteria from 5 dpi and 10 dpi, however direct isolation was possible from 15 dpi feces. In phage treated group, postmortem lesion was better than non-phage treated group. Recently, antibiotic resistance concerns on the food-borne bacterial pathogens have been increasing because of the wide spread of the antibiotics resistance genes. This concern is widely transmitted to the human related public health. As one of the alternative treatments on the bacterial pathogens, attempt using phages have been made to control the bacterial diseases. The positive possibility of the trail using phage was observed to control the S. enterica serovar Enteritidis in this study even though the further analysis has been remained.
One hundred representative species of fungi in Korea were selected and their Korean names were proposed to increase interest in fungi among Korean people. This task was performed under the supervision of the Committee of Mycological Terms, under the Korean Society of Mycology. First, the committee established the criteria for selecting 100 representative species of fungi in Korea and then selected the candidate fungal species accordingly. To ensure the uniformity and stability of Korean fungal names, the principle of naming fungi in Korean was established, and the candidate Korean fungal names were presented accordingly. Finally, the candidate Korean fungal names were posted online to collect opinions of the members of the Korean Society of Mycology. The candidate Korean names of the plant pathogenic fungi and mushrooms were reviewed by the Korean Society of Plant Pathology and the Korean Society of Mushroom Science, respectively. After their opinions were considered, the Korean names for 100 representative fungi in Korea were finally determined. The 100 fungi comprised 41 common molds and yeasts, 28 plant pathogenic fungi, and 31 mushrooms.
With the incidence of antibiotic resistant bacteria there is increasing interest in natural products such as herb extract and probiotics to control antibiotic resistant bacteria. This study was focused on the determination of antimicrobial activity of Opuntia ficus-indica var. saboten against Salmonella enetrica serovar Enteritidis (S. enterifidis), S. enterica serovar Typhimurium (S. Typhimurium) DT 104 and Escherichia coli 0157:H7. Though bactericidal effect of 0. ficus-indica var. saboten was not observed, it had significant inhibitory activity against Salmonella spp. and E. coli O157:H7 on the Moulter Hinton agar containing its solution dissolved in deionized water. To investigate the antimicrobial activity in vivo, mice were challenged with 5. Typhimurium DT104 (3.7$\times$108 cfu/mouse) after pre-feeding 0. ficus-indica var. saboten solution. The fecal shedding of S. Typhimurium DT104 was more dramatically decreased and not detectable in feces and intestines 3 days after challenge in mice fed with 0. ficus-indica var. saboten. Antibody responses of the intestinal IgA were also significantly increased in mice fed with 0. ficus-indica var. saboten. These findings suggest that Opuntia ficus-indica var. saboten decreased the shedding of S. Typhimurium DT104 in vitro and also in the gastrointestinal tract in mice. In addition, administration of the product might enhance the mucosal immune response against S. Typhimurium DT 104. In conclusion, Opuntia ficus-indica var. saboten might be useful to control antibiotic resistant bacteria in vivo and in vitro.
Purpose: Depression is a prevalent mental health concern globally including South Korea. Given the growing interest in the relationship between diet and mental health, this study aimed to investigate the association between seafood consumption and depression among Korean adults. Methods: A cross-sectional analysis was conducted using data from the Korea National Health and Nutrition Examination Survey (KNHANES, 2014-2020). The study included 18,149 participants (7,541 men and 10,608 women) aged 19 years and older who completed the Patient Health Questionnaire (PHQ-9). Seafood intake levels were assessed using a oneday 24-hour dietary recall, and participants were categorized into three tertiles by gender. Depression status was determined using the PHQ-9 scores and the self-report of the doctor's diagnosis and treatment. Multivariable logistic regression analysis was performed to assess the association between seafood consumption and depression in both genders. Results: Participants with a higher seafood intake had a significantly lower nutritional density of total fat, while the nutritional density of omega-3 polyunsaturated fatty acids was significantly higher. The prevalence of depression was significantly lower in the highest tertile of seafood consumption compared to the lowest tertile in both men (p < 0.001) and women (p < 0.001). After adjusting for confounding factors, the highest tertile of seafood consumption demonstrated a decreased risk of depression compared to the lowest tertile in men (odds ratio [OR], 0.71; 95% confidence interval [CI], 0.51-0.99; p-trend = 0.020) and women (OR, 0.73; 95% CI, 0.59-0.91; p-trend = 0.004). Conclusion: The findings of this study suggest that consuming seafood rich in omega-3 fatty acids may potentially reduce the risk of depression in the adult population.
Myung-Ho Lim;Sang Dae Yun;Eun Young Kim;Sung Aeong Oh;Soon-Ki Park
Journal of Plant Biotechnology
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v.50
/
pp.275-289
/
2023
Since the implementation of the Living Modified Organisms (LMOs) Act in 2008, approximately 10 million tons of genetically modified corn, soybean, potato, canola, and other crops have been imported into South Korea. The import approval procedures have been completed for approximately 191 cases that include seven crops. Of these, approximately 90 cases, excluding crossbreeds of approved LMOs, were reviewed via consultation risk evaluation in four areas: human health, crop culture, natural ecology, and marine fishery environment. LMO developers in South Korea, who are major stakeholders in the import of LMO crops produced overseas, have raised concerns regarding procedural inefficiency in consultation reviews and the need of excessive reviews that are unsuitable for food-feed processing purposes. These procedures reflect the perspective of consultation agencies that deviate from the nature of risk assessment and demand specific supplementary data that do not reflect familiarity and substantial equilibrium. Based on frequent instances of unintentional environmental release of LMO crops imported into Korea, the ministries responsible for consultation insist on a review that considers the climate and natural environment of Korea. In addition, the ministries mandate that their reviews reflect the expertise of competent ministries and are based on risk assessment principles and methods in accordance with international guidelines. In this regard, considering that traits introduced into LMO crops involving familiar agricultural crops have been considered safe for more than two decades, we have suggested reasonable alternatives to several risk assessment items for agricultural LMOs. These alternatives can mitigate conflicts of interest among key stakeholders within the scope of the current LMO regulations.
Great Britain and the United States and Finland are having an interest in long policy subject about child design education through early design education. And they approaches and practices it systematically. The research about the design learning program instance of advanced nation of primary school's design education for various objective is necessary for use with the fundamental reference data for an elementary design education. And so, This research presented the program instance investigation and analysis result of British primary school's design education. U.K is teaching an primary design education from two subjects of Art & Design and Design and Technology which is a legal subject with national curriculum. The analysis result of design relation unit learning program of two subjects is: Design relation unit learning programs of 'Design and Technology' subject's 20 unit which except 4 food relation unit is largely scientific engineering contents that include utility function contents in part. The reason is as behavior styles based on Design process solve problems scientifically & rationally. Design relation 6 units in subject of Art & Design which except the units which relates with the pure fine arts and architecture in 19 units is aesthetic-symbolic and utility-functional contents largely. And so, the result was analyzed about relation of scientific-engineering content of 'Arts & Design' subject is insufficient comparing with 'Design and Technology' subject Specially, I think that the design relation's unit learning program instances of 'Design and Technology' subject of the British primary school which have been presented by this research paper is a possibility becoming one reference model for a program development. And so I expects that this research could be applied in the program development for the primary design education of primary teacher & education agency.
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