• Journal of Korean Elementary Science Education
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• v.38 no.3
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• pp.375-386
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• 2019

This study explores how elementary school students construct food pyramid prediction models using scientific reasoning. Thirty small groups of sixth-grade students in the Kyoungki province (n=138) participated in this study; each small group constructed a food pyramid prediction model based on scientific reasoning, utilizing prior knowledge on topics such as biotic and abiotic factors, food chains, food webs, and food pyramid concepts. To understand the scientific reasoning applied by the students during the modeling process, three forms of qualitative data were collected and analyzed: each small group's discourse, their representation, and the researcher's field notes. Based on this data, the researcher categorized the students' model patterns into three categories and identified how the students used scientific reasoning in their model patterns. The study found that the model patterns consisted of the population number variation model, the biological and abiotic factors change model, and the equilibrium model. In the population number variation model, students used phenomenon-based reasoning and relation-based reasoning to predict variations in the number of producers and consumers. In the biotic and abiotic factors change model, students used relation-based reasoning to predict the effects on producers and consumers as well as on decomposers and abiotic factors. In the equilibrium model, students predicted that "the food pyramid would reach equilibrium," using relation-based reasoning and model-based reasoning. This study demonstrates that elementary school students can systematically elaborate on complicated ecology concepts using scientific reasoning and modeling processes.

• Journal of Korean Elementary Science Education
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• v.31 no.1
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• pp.71-83
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• 2012

The purpose of this study was to explore ecological concepts, epistemological reasoning and reasoning processes through constructing 'food web and food pyramid' in ecology. We conducted classes which involved a 'food web and food pyramid' for $6^{th}$ grade students. Each class is constructed of small groups to do modeling and epistemological reasoning through communication. The researcher had videotaped and recorded each class and have made transcription about classes. We analysed patterns of 'food web and food pyramid models' and reasoning processes according to scientific epistemology using transcription data and student outputs. As a result, students represented phenomenon-based reasoning, relation-based reasoning and model-based reasoning in scientific epistemology from their modeling. Students usually did relation-based reasoning and model-based reasoning in food web which explains ecological phenonenon, while they usually did model-based reasoning in food pyramid which expects ecological phenomenon. Student's reasoning can be limited when they have misconception of scientific knowledge and are limited by fragmentary knowledge. This represents that students has to do relation-based reasoning and model-based reasoning is beneficial in their ecological model. It also suggests that students need to define correct-conception related to ecological modeling(food web, food pyramid).

• Journal of the Korean Society of Food Culture
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• v.22 no.1
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• pp.70-76
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• 2007

The purpose of this study was to measure the effects of food neophobia, nausea, and learned food aversion on food rejection and appetite. A total of 250 questionnaires were completed. Path analytic model was used to measure the relationships between variables. Results of the study demonstrated that the path analysis result for the data also indicated excellent model fit. The effects of food neophobia on nausea and food rejection were statistically significant. The effect of food neophobia on learned food aversion and appetite was not statistically significant. As expected, nausea had a significant effects on learned food aversion and appetite. Moreover, nausea played a perfect mediating role in the relationship between food neophobia and appetite. Nausea played a perfect mediating role in the relationship between food neophobia and learned food aversion. Learned food aversion played a partial mediating role in the relationship between nausea and appetite. Learned food aversion did not play a mediating role in the relationship between food neophobia and appetite. In conclusion, based on path analyses, a model was proposed of interrelations between variables. It should be noted that the original model was modified and should, preferably, be validated in future research.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.120-124
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• 2011

Predictive mathematical models were developed for predicting the kinetics of growth of Listeria monocytogenes in smoked salmon, which is the popular ready-to-eat foods in the world, as a function of temperature (4, 10, 20 and $30^{\circ}C$). At these storage temperature, the primary growth curve fit well ($r^2$=0.989~0.996) to a Gompertz equation to obtain specific growth rate (SGR) and lag time (LT). The Polynomial model for natural logarithm transformation of the SGR and LT as a function of temperature was obtained by nonlinear regression (Prism, version 4.0, GraphPad Software). Results indicate L. monocytogenes growth was affected by temperature mainly, and SGR model equation is $365.3-31.94^*Temperature+0.6661^*Temperature^{\wedge^2}$ and LT model equation is $0.1162-0.01674^*Temperature+0.0009303^*Temperature{\wedge^2}$. As storage temperature decreased $30^{\circ}C$ to $4^{\circ}C$, SGR decreased and LT increased respectively. Polynomial model was identified as appropriate secondary model for SGR and LT on the basis of most statistical indices such as bias factor (1.01 by SGR, 1.55 by LT) and accuracy factor (1.03 by SGR, 1.58 by LT).

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.364-369
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• 2011

Levels of carbon dioxide gas, a metabolite of microbial growth, have been reported to parallel the onset of microbial spoilage and may be used as a convenient index for a packaged food's shelf life. This study aimed to establish a kinetic model of $CO_2$ production from perishable food for the potential use for shelf life control in the food supply chain. Aerobic bacterial count and package $CO_2$ concentration were measured during the storage of seasoned pork meat at four temperatures (0, 5, 10 and $15^{\circ}C$), and their interrelationship was investigated to establish a mathematical model. The microbial growth at constant temperature was described by using model of Baranyi and Roberts. $CO_2$ production from the stored food could be explained by taking care of its yield and maintenance factors linked to the microbial growth. By establishing the temperature dependence of the microbial growth and $CO_2$ yield factor, $CO_2$ partial pressure or concentration in package headspace could be estimated to a limited extent, which is helpful for controlling the shelf life under constant and dynamic temperature conditions. Application and efficacy of the model needs to be improved with further refinement in the model.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.715-720
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• 2006

This study was performed to develop a predictive model for the growth kinetics of Listeria monocytogenes in tryptic soy broth (TSB) using a response surface model with a combination of potassium lactate (PL), temperature, and pH. The growth parameters, specific growth rate (SGR), and lag time (LT) were obtained by fitting the data into the Gompertz equation and showed high fitness with a correlation coefficient of $R^2{\geq}0.9192$. The polynomial model was identified as an appropriate secondary model for SGR and LT based on the coefficient of determination for the developed model ($R^2\;=\;0.97$ for SGR and $R^2\;=\;0.86$ for LT). The induced values that were calculated using the developed secondary model indicated that the growth kinetics of L. monocytogenes were dependent on storage temperature, pH, and PL. Finally, the predicted model was validated using statistical indicators, such as coefficient of determination, mean square error, bias factor, and accuracy factor. Validation of the model demonstrates that the overall prediction agreed well with the observed data. However, the model developed for SGR showed better predictive ability than the model developed for LT, which can be seen from its statistical validation indices, with the exception of the bias factor ($B_f$ was 0.6 for SGR and 0.97 for LT).

• Journal of Food Hygiene and Safety
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• v.26 no.1
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• pp.25-30
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• 2011

In this study, predictive mathematical models were developed to predict the kinetics of Listeria monocytogenes growth in the mixed fresh-cut vegetables, which is the most popular ready-to-eat food in the world, as a function of temperature (4, 10, 20 and $30^{\circ}C$). At the specified storage temperatures, the primary growth curve fit well ($r^2$=0.916~0.981) with a Gompertz and Baranyi equation to determine the specific growth rate (SGR). The Polynomial model for natural logarithm transformation of the SGR as a function of temperature was obtained by nonlinear regression (Prism, version 4.0, GraphPad Software). As the storage temperature decreased from $30^{\circ}C$ to $4^{\circ}C$, the SGR decreased, respectively. Polynomial model was identified as appropriate secondary model for SGR on the basis of most statistical indices such as mean square error (MSE=0.002718 by Gompertz, 0.055186 by Baranyi), bias factor (Bf=1.050084 by Gompertz, 1.931472 by Baranyi) and accuracy factor (Af=1.160767 by Gompertz, 2.137181 by Baranyi). Results indicate L. monocytogenes growth was affected by temperature mainly, and equation was developed by Gompertz model (-0.1606+$0.0574^*Temp$+$0.0009^*Temp^*Temp$) was more effective than equation was developed by Baranyi model (0.3502-$0.0496^*Temp$+$0.0022^*Temp^*Temp$) for specific growth rate prediction of L.monocytogenes in the mixed fresh-cut vegetables.

• Nutrition Research and Practice
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• v.6 no.4
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• pp.357-365
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• 2012

This study was conducted to develop a construct model regarding the daily activities, emotional security provided by food, enjoyment of food, level of satisfaction with delivered food, and the quality of life of homebound seniors who benefitted from meal delivery programs. The data were analyzed by SAS 9.2 and the Structural Equation Model (SEM), which was created by Analysis of Moment Structure (AMOS) 5.0 packages. The reliability of the data was confirmed by an exploratory factor analysis and through a Cronbach's alpha coefficient, and the measurement model proved to be appropriate by a confirmatory factor analysis of the measurement model in conjunction with AMOS. The results of the correlations between all the variables showed significant positive correlations (P < 0.05). The path analysis demonstrated that the daily activities (P < 0.01) and the emotional security created by food (P < 0.05) had positive correlations with the foodservice satisfaction (P < 0.05), while the daily activities (P < 0.05), the sense of emotional security made by food (P < 0.05), and food enjoyment (P < 0.05) also presented significant positive correlations with the quality of life. However, the food service satisfaction was shown to directly, but not significantly, affect the quality of life. This revealed that the current meal delivery programs needed to be improved in several directions.

• Culinary science and hospitality research
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• v.13 no.2
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• pp.153-162
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• 2007

The purpose of this study was to examine the mediating role of nausea, learned food aversion, and appetite on the relationship between food neophobia and food rejection. A total of 250(122 healthy males and 128 healthy females) questionnaires were completed. Path analytic model was used to measure the mediating effect. Results of the study demonstrated that the path analytic result for the data also indicated excellent model fit. Furthermore, the mediating analysis indicated that the influence of food neophobia was mediated by mediator. The effect of food neophobia on appetite was perfectly mediated by nausea and learned food aversion. In the contests of general food rejection, the effect of food neophobia on food rejection was perfectly mediated by appetite. It should be noted that the original model was modified and should, preferably, be validated in future research.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.3
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• pp.294-301
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• 2008

The purpose of this study was to analyze the effects of food neophobia on food choice motives, such as health concern, weight control, ethical concern, and vegetable consumption. A total of 290 questionnaires were completed. Moderated regression analysis was used to measure the moderating effects of food neophobia. Results demonstrated Model 3 to be the best fit, compared to Model 1 and Model 2. In Model 3, the effects of health concern and food neophobia on vegetable consumption were statistically significant (p<0.01). However, the effects of weight control and ethical concern on vegetable consumption were not statistically significant (p>0.05). As expected, the combination of health concern and food neophobia had a significant effect on vegetable consumption (p<0.05). However, weight control and food neophobia, and ethical concern and food neophobia had no significant effects on vegetable consumption (p>0.05). Moreover, health concern related to vegetable consumption was statistically significant at all levels of food neophobia, except, when level of food neophobia was high (p<0.001). In developing and testing moderated regression models, which integrate relationship among food neophobia, health concern, weight control, ethical concern and vegetable consumption in the future, this study may provide a deeper understanding of the complex relationship among vegetable consumption behavior-related variables.