• Molecules and Cells
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• v.37 no.1
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• pp.74-80
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• 2014

The peroxisome is an intracellular organelle that responds dynamically to environmental changes. Various model organisms have been used to study the roles of peroxisomal proteins in maintaining cellular homeostasis. By taking advantage of the zebrafish model whose early stage of embryogenesis is dependent on yolk components, we examined the developmental roles of the D-bifunctional protein (Dbp), an essential enzyme in the peroxisomal ${\beta}$-oxidation. The knockdown of dbp in zebrafish phenocopied clinical manifestations of its deficiency in human, including defective craniofacial morphogenesis, growth retardation, and abnormal neuronal development. Overexpression of murine Dbp rescued the morphological phenotypes induced by dbp knockdown, indicative of conserved roles of Dbp during zebrafish and mammalian development. Knockdown of dbp impaired normal development of blood, blood vessels, and most strikingly, endoderm-derived organs including the liver and pancreas - a phenotype not reported elsewhere in connection with peroxisome dysfunction. Taken together, our results demonstrate for the first time that zebrafish might be a useful model animal to study the role of peroxisomes during vertebrate development.

• Health Policy and Management
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• v.4 no.2
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• pp.111-125
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• 1994

In developing total hospital information system, large amount of time and expense are to be spent while its results are likely to lead itself to end-users' dissatisfaction. Some of the main complaints on the part of end-users come from insufficient consideration of end-users environment as well as inappropriate representation of their requirement in the system alalysis and design. This papre addresses some advantages of Essential Logical Modeling Process for better analysis and design, explaining by example the developmental process of the Patent Management and Accounting System for a tertiary care hospital. In the case, the Essential Model, suggested by McMenamin and Palmer, proved to be an effective tool for clear separation of analysis and design phase and for better communication among system developers and with end-users. The modeling process itself contributed to better program modularity as well, shown in a Structured Chart. Difficulties in learning how to identify' essential activities' for the modeling practice were experienced in the beginnins stage, which were, however, overcome by elaborating some heuristic guideling and by rdferring to necessary tools including State Transition Diagram, Control Flow Diagram, and so many. While full evaluation of the Essential Model usag remains to wait till the completion of the case project, its strengt in making clear distinction between analysis and design phase was enough to be attractive to system analysts. The model concepts are open to many further application fields, particularly such areas as business re engineering, process remodeling, office automation, and organizational restructuring.

• Journal of the Optical Society of Korea
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• v.12 no.1
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• pp.25-30
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• 2008

The optical performances of 15-inch edge-lit backlight were simulated by using a Monte Carlo ray-tracing technique. The backlight model was built by combining a wedge-type light guide plate, a diffuser sheet, a tubular fluorescent lamp with a lamp reflector, and two crossed prism sheets. Angular distributions of the luminance on each optical component obtained from simulation were consistent with those obtained from experiments on a real 15-inch backlight. The constructed backlight model was used to evaluate the optical performances of a micro-pyramid film. It was found that the on-axis luminance gain on the pyramid film is higher than that on one prism film but much lower than that on the two crossed prism films. These results suggest that a reliable simulation model can be used to develop new hybrid films and to optimize the optical structure of edge-lit backlight in order to reduce the developmental period.

• Journal of The Korean Association For Science Education
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• v.32 no.3
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• pp.477-485
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• 2012

This study introduces the development of elementary science textbooks in Korea. In Korea there has been eight revisions to the National curriculum and the development of nine textbooks. The State of Korea has organized textbook development teams, but this time the State chose the development team through public contest. Researchers suggested the 'FLOW' development model based upon results of studies in creative education and developed the new science textbooks. The 'FLOW' model includes four stages, aimed towards capturing students' interest in science (Fun Science), engaging students in various scientific inquiries and experiences (Lab. Experience), organizing their own knowledge of science (Organizing Knowledge), and to encourage students to become little scientists (Willing to be a Scientist). The textbook is a research-developmental textbook that utilizes various literature and exploration-strategic textbooks. The textbook's basis is formed upon scientists' experiences that assist in the realization of 'inquiry' that is emphasized within the science field.

• Journal of Korean Elementary Science Education
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• v.32 no.2
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• pp.139-158
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• 2013

This study investigated elementary students' (grade 4~6) learning progressions for water cycling drawn from iterative assessments using ordered multiple-choice (OMC) items. An assessment system, which consisted of construct map, item design, outcome space, and measurement model, was employed in this study to examine children's learning progressions. At the first stage of the assessment system, a construct map was designed on which children's conceptual understandings from naive to most sophisticated were represented. At the item design stage, 8 OMC items were drawn from the construct map. Each item option of the OMC items was scored from 0 to 3 according to its level of understanding at the stage of outcome space. As a measurement model, Rasch model, a branch of item response theory, was applied to interpreting the outcomes of the OMC items. This cycle of assessment system was furtherly implemented iteratively in order to elaborate on the first version of water cycling learning progression. In conclusion, children's understanding of water cycling could be described in two aspects: water distribution and water movement. We identified children's conjectural developmental pathways about water cycling existed from superficial and naive accounts to more complex and abstract accounts.

• Reproductive and Developmental Biology
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• v.33 no.3
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• pp.119-123
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• 2009

The two dimensional quantitative structure-activity relationships (2D-QSARs) models concerning the binding affinity constants ($p[Od.]_{50}$) between 2-cyclohexyltetrahydropyrane and 2-cyclohexyltetrahydrofurane analogues as substrates, and bovine odorant binding protein (bOBP) as receptor were derived by multiple regression analyses method and discussed. The statistical quality of the optimized 2D-QSAR model (5) was good (r=0.907). From the model, the binding affinity constants ($p[Od.]_{50}$) were dependent upon the optimal value ($(TL)_{opt.}$=2.737) of total lipole (TL) of substrate molecules. Based on these findings, the high active compounds predicted by optimized 2D-QSAR model (5) were 2-(dimethylcyclohexyl)tetrahydropyrane molecule and their isomer molecules. The binding affinity constants regarding bOBP of the tetrahydrofuryl-2-yl family compounds were dependent upon the hydrophobicity (logP) of whole substrate molecules. In any case of porcine odorant-binding proteins (pOBP), the constants were dependent upon the hydrophobicity (${\pi}x={\log}P_X-{\log}P_H$) of substituents (R) in substrate molecules. Also, from the optimal values of hydrophobic constant, the hydrophobicity for bOBP influenced ca. twice time bigger (bOBP>pOBP) than that for pOBP.

• Plant Biotechnology Reports
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• v.2 no.1
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• pp.59-73
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• 2008

Several aspects of photoperception and light signal transduction have been elucidated by studies with model plants. However, the information available for economically important crops, such as Fabaceae species, is scarce. In order to incorporate the existing genomic tools into a strategy to advance soybean research, we have investigated publicly available expressed sequence tag (EST) sequence databases in order to identify Glycine max sequences related to genes involved in light-regulated developmental control in model plants. Approximately 38,000 sequences from open-access databases were investigated, and all bona fide and putative photoreceptor gene families were found in soybean sequence databases. We have identified G. max orthologs for several families of transcriptional regulators and cytoplasmic proteins mediating photoreceptor-induced responses, although some important Arabidopsis phytochrome-signaling components are absent. Moreover, soybean and Arabidopsis genefamily homologs appear to have undergone a distinct expansion process in some cases. We propose a working model of light perception, signal transduction and response-eliciting in G. max, based on the identified key components from Arabidopsis. These results demonstrate the power of comparative genomics between model systems and crop species to elucidate several aspects of plant physiology and metabolism.

• Korea journal of population studies
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• v.11 no.1
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• pp.97-116
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• 1988

This study examines the socioeconomic determinants of fertility behavior in Korea by developing a model which simultaneously takes into account both individual and community-level differences. It especially focuses on the micro-macro nexus of fertility behavior depending on social contexts. This study utilizes micro data obtained from the 1974 Korean National Fertility Survey(KNFS), and macro data obtained from Korean government statistics. The framework of the model is formalized as a set of structural equations modelling the fertility process. The model is formed on a cohort-specific processual basis and is restricted to five-year birth cohorts. Three cohorts of women are studied : those aged 30-34, 35-39, and 40-44. The model includes three fertility-process components : age at first birth, early fertility, and later fertility, which are defined by reference to the age of the mother. The results of this study indicate that socioeconomic development in Korea results in increased age at first birth and reduced numbers of children per couple. In addition to the developmental change, Korea's fertility decline is found to be facilitated by family planning programs. As expected, the effect of family planning on fertility is greater among better-educated women than among poorly educated women. The inconsistent but suggestive result, however, is that the effect of socioeconomic development on fertility is greater among less-privileged women than among more-previleged women.

• Educational Technology International
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• v.20 no.1
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• pp.25-55
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• 2019

The core purpose of the study is to develop and validate an ADDIE model based instructional model for English Language Teaching (ELT) in early childhood classroom in Bangladesh as an aid to teachers to reconstruct their knowledge and experience more strategically, and for them to design and implement their instruction more structurally. This study is developmental in nature which has been divided in five phases as follows. Phase I: Existing methods and instructional strategy review, Phase II: Instructional model development, Phase III: Delphi 1st round, Phase IV: Delphi 2nd round and Phase V: Model validation. After reviewing relevant literature and existing strategy in phase I, the 1st version of instructional model is made phase II. Next in phase III and phase IV, two rounds of Delphi have been conducted where experts related to different concerning areas of this study reviewed the 1st version and gradually the final version of the instructional model is made. Finally, the instructional model for English teachers of early childhood classroom in Bangladesh got validated by the same Delphi panelists in Phase V. In respect with each phases of ADDIE, the instructional model elaborates the 1) representative key points, 2) instructors' activities prescribed for the instructors, 3) supporting strategies. Both the conceptual and procedural models are included in this study for clearer identification of the whole process. Lastly the study provides some recommendations for instructors and practitioners on choosing the instructional model like doing prior need analysis, incorporating teacher training programs, training students, keeping on researching for finding effective teaching technique and tools and being open to changes etc. In addition, the study also acknowledges its limitations like not being able to consider the psychological factors due to time limitation. Finally, at the end the study points out the areas that welcome further research.

• Journal of The Korean Association For Science Education
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• v.16 no.4
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• pp.429-440
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• 1996

This study examined the effects of the ARCS model for science education and found a way of improving ARCS while finding any weaknesses. More specific research questions were as follows: 1) Does the ARCS model enhance the learners' achivement in highschool Earth Science significantly?; 2) Does the ARCS model enhance the learners' motivation in highschool Earth Science significantly?; 3) What are the weaknesses of the prescriptions of the ARCS model for designing a lesson, if any?; 4) How can the weaknesses of the prescriptions of the ARCS modeI be overcome? In order to fulfill the purpose of this study, the two major research methodologies were implemented: pretest-posttest control group design and formarive research. This study was conducted in two distinct phases: 1) designing a set of instructions for 4 weeks with the principles of the ARCS model (to find the weaknesses of the ARCS model) and 2) teaching the instructions and checking the effectiveness of the ARCS model by pretest and posttest with control and experimental groups(to find weaknesses of the underlying theory of the ARCS). After the experiment, each group took an achievement test and an attitude test on the given instruction and gathered data were analyzed with t-tests. Also, from each four classes 7$\sim$8 students were randomly sampled and individually interviewed about the instructional effectiveness and their preference on the instructions. The results of this study are summarized as follows: Significant differences between the control group and experimental group are seen in three components; Attention, relevance, and satisfaction. No significant differences are seen in the attitude of confidence. The weakness of the prescriptions of the ARCS model, are insufficient of strategy for 'confidence'. For overcoming the weaknesses of the prescriptions of the ARCS model, developmental type research is needed.