• Journal of The Korean Association For Science Education
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• v.27 no.8
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• pp.677-692
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• 2007

In this study, university students were provided with repeated opportunities to represent their ideas graphically, and to examined via their drawings the extent to which they could visualize macroscopic phenomena microscopically. These drawings provided insight into the students' basic understanding of solution chemistry, revealing three conceptual models: the Undifferentiated Symbolic Model, the Particulate Model, and the Symbolic Ionic Model. Generally speaking, students who had poor conceptual understanding tended to exhibit the Undifferentiated Symbolic Model, whereas students with deeper understanding tended to employ the Symbolic Ionic Model. Students' conceptual comprehension was predictable from their graphical representations, which better elucidated what they actually comprehended about the phenomena, as opposed to their ambiguous verbal descriptions alone. The results of this study demonstrated a lack of development in university students' conceptions of solutions. Their weakness in understanding at the molecular-level became more obvious when they were asked to represent their ideas in drawings. Few students exhibited expert knowledge, and several common misconceptions were found, which indicated typical difficulties students have perceiving common phenomena at the molecular level. The findings of this study illustrate how eliciting graphical representations can be used to assess students' conceptual understandings.

• Journal of Gastric Cancer
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• v.22 no.4
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• pp.273-305
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• 2022

Gastric cancer (GC) is one of the most common lethal malignant neoplasms worldwide, with limited treatment options for both locally advanced and/or metastatic conditions, resulting in a dismal prognosis. Although the widely used morphological classifications may be helpful for endoscopic or surgical treatment choices, they are still insufficient to guide precise and/or personalized therapy for individual patients. Recent advances in genomic technology and high-throughput analysis may improve the understanding of molecular pathways associated with GC pathogenesis and aid in the classification of GC at the molecular level. Advances in next-generation sequencing have enabled the identification of several genetic alterations through single experiments. Thus, understanding the driver alterations involved in gastric carcinogenesis has become increasingly important because it can aid in the discovery of potential biomarkers and therapeutic targets. In this article, we review the molecular classifications of GC, focusing on The Cancer Genome Atlas (TCGA) classification. We further describe the currently available biomarker-targeted therapies and potential biomarker-guided therapies. This review will help clinicians by providing an inclusive understanding of the molecular pathology of GC and may assist in selecting the best treatment approaches for patients with GC.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.117-132
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• 1987

Plants are inherited spatial and temporal coordination systems in their growth and differentiation processes which are precisely governed by the two interlocked control systems; autogenous and environmental. Looking into the overall course of plant development from molecular to organismal level, it can be comparable to a concerto for plant hormones, environmental stimuli and plant genomic orchestra conducted by an unidentified virtuoso. Some of the recent significant attempts to puzzle out the mystery of the life processes of plant development are briefly reviewed. The revolutionary advances in understanding the mystic processes are contemporarily achieved by the application of various molecular techniques. The characterization of plant genomes is now attained through recombinant DNA approaches, and the sensitive detection of specific gene products during the plant development is perimitted by the immunochemical procedures. However, along with the recognition of underlying molecular events such as developmental changes in gene expression and hormone-receptor interrelation associated with tissue sensitivity to hormones, more emphasis should be placed upon the physiological approaches of organismal level for the understanding the correlative systems of the developmental processes of plants as intact eukaryotic organisms.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.3
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• pp.229-239
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• 2009

Molecular imaging strives to visualize processes in living subjects at the molecular level. Monitoring biochemical processes at this level will allow us to directly track biological processes and signaling events that lead to pathophysiological abnormalities, and help make personalized medicine a reality by allowing evaluation of therapeutic efficacies on an individual basis. Although most molecular imaging techniques emerged from the field of oncology, they have now gradually gained acceptance by the cardiovascular community. Hence, the availability of dedicated high-resolution small animal imaging systems and specific targeting imaging probes is now enhancing our understanding of cardiovascular diseases and expediting the development of newer therapies. Examples include imaging approaches to evaluate and track the progress of recent genetic and cellular therapies for treatment of myocardial ischemia. Other areas include in vivo monitoring of such key molecular processes as angiogenesis and apoptosis, Cardiovascular molecular imaging is already an important research tool in preclinical experiments. The challenge that lies ahead is to implement these techniques into the clinics so that they may help fulfill the promise of molecular therapies and personalized medicine, as well as to resolve disappointments and controversies surrounding the field.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.49-50
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• 2002

Rapid advancements in analytical instrumentations and techniques in the last several decades offer an unprecedented opportunity to analyze the complex chemistry and probe the surfaces for chemical evidence. Recent developments in nanotechnology provide further ability to examine phenomena and mechanisms at the nanometer level. As a result of these advances, our understanding of the complex lubrication system has improved significantly. This paper will attempt to provide a molecular basis of how lubricant and additives function in lubrication.

• Applied Science and Convergence Technology
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• v.24 no.5
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• pp.151-155
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• 2015

The interfacial electronic structure between zinc phthalocyanine (ZnPc) and aluminumdoped zinc oxide (AZO) substrates has been evaluated by ultraviolet photoemission spectroscopy and angle-dependent x-ray absorption spectroscopy to understanding the molecular orientation of a ZnPc layer on the performance of small molecule organic photovoltaics (OPVs). We find that the ZnPc tilt angle improves the ${\pi}-{\pi}$ interaction on the AZO substrate, thus leading to an improved short-circuit current in OPVs based on phthalocyanine. Furthermore, the molecular orientation-dependent energy level alignment has been analyzed in detail using ultraviolet photoemission spectroscopy. We also obtained complete energy level diagrams of ZnPc/AZO and ZnPc/indium thin oxide.

• The Plant Pathology Journal
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• v.27 no.2
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• pp.103-109
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• 2011

The fungal genus Cercospora is one of the most ubiquitous groups of plant pathogenic fungi, and gray leaf spot caused by C. zeae-maydis is one of the most widespread and damaging foliar diseases of maize in the world. While light has been implicated as a critical environmental regulator of pathogenesis in C. zeae-maydis, the relationship between light and the development of disease is not fully understood. Recent discoveries have provided new insights into how light influences pathogenesis and morphogenesis in C. zeae-maydis, particularly at the molecular level. This review is focused on integrating old and new information to provide an updated perspective of how light influences pathogenesis, and provides a working model to explain some of the underlying molecular mechanisms. Ultimately, a thorough molecular-level understanding of how light regulates pathogenesis will augment efforts to manage gray leaf spot by improving host resistance and disease management strategies.

• Molecules and Cells
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• v.26 no.1
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• pp.1-4
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• 2008

A gene's influence on an organism's Darwinian fitness ultimately determines whether it will be lost, maintained or modified by natural selection, yet biologists have few gene expression systems in which to measure whole-organism gene function. In the Department of Molecular Ecology at the Max Planck Institute for Chemical Ecology we are training "molecularly enabled field biologists" to use transformed plants silenced in the expression of environmentally regulated genes and the plant's native habitats as "laboratories." Research done in these natural laboratories will, we hope, increase our understanding of the function of genes at the level of the organism. Examples of the role of threonine deaminase and RNA-directed RNA polymerases illustrate the process.

• Journal of Microbiology and Biotechnology
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• v.19 no.3
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• pp.299-306
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• 2009

Dissolved oxygen (DO) has a significant effect on the molecular weight of hyaluronic acid (HA) during the fermentation of Streptococcus zooepidemicus. Therefore, to further investigate the effect of DO on the yield and molecular weight of HA, this study compared the metabolic flux distribution of S. zooepidemicus under aerobic conditions at various DO levels. The metabolic flux analysis demonstrated that the HA synthesis pathway, considered a dependent network, was little affected by the DO level. In contrast, the fluxes of lactate and acetate were greatly influenced, and more ATP was generated concomitant with acetate at a high DO level. Furthermore, the has gene expression and HA synthase activity were both repressed under anaerobic conditions, yet not obviously affected under aerobic conditions at various DO levels. Therefore, it was concluded that the HA molecular weight would seem to depend on the concomitant effect of the generation of ATP and reactive oxygen species. It is expected that this work will contribute to a better understanding of the effect of the DO level on the mechanism of the elongation of HA chains.

• BMB Reports
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• v.33 no.6
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• pp.427-439
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• 2000

The activity of the phagocyte respiratory burst oxidase is regulated by complex and dynamic alterations in protein-protein interactions that result in the rapid assembly of an active multicomponent NADPH oxidase enzyme on the plasma membrane. While the enzymatic activity has been studied for the past 20 years, the past decade has seen remarkable progress in our understanding of the enzyme and its activation at the molecular level. This article describes the current state of knowledge, and proposes a model for the mechanism by which protein-protein interactions regulate enzyme activity in this system.