• Journal of Life Science
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• v.30 no.8
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• pp.672-679
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• 2020

Distal myopathy is a clinically and genetically heterogeneous group of degenerative diseases of the distal muscle. Glycogen storage disease type IXD (GSD9D) is a metabolic distal myopathy characterized by muscle deficiency of phosphorylase kinase, a key regulatory enzyme in glycogen metabolism. Affected individuals may develop muscle weakness, degeneration, and cramps, as well as abnormal muscle pain and stiffness after exercise. It has been reported that mutations in the PHKA1 gene which encodes the alpha subunit of muscle phosphorylase kinase cause GSD9D. In this study, we examined a Korean GSD9D family with a c.3314T>C (p.I1105T) mutation in the PHKA1 gene. This mutation has not been previously reported in any mutation database nor was it found in 500 healthy controls. The mutation region is well conserved in various other species, and in silico analysis predicts that it is likely to be pathogenic. To date, only seven mutations in the PHKA1 gene have been documented, and this is the first report of Korean GSD9D patients. This study also describes and compares the clinical symptoms and pathological conditions of previously reported cases and these Korean patients. We believe that our findings will be useful for the molecular diagnosis of GSD9D.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.5917-5935
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• 2012

Background: Hepatitis C virus (HCV) causes acute and chronic human hepatitis infection and as such is an important global health problem. The virus was discovered in the USA in 1989 and it is now known that three to four million people are infected every year, WHO estimating that 3 percent of the 7 billion people worldwide being chronically infected. Humans are the natural hosts of HCV and this virus can eventually lead to permanent liver damage and carcinoma. HCV is a member of the Flaviviridae family and Hepacivirus genus. The diameter of the virus is about 50-60 nm and the virion contains a single-stranded positive RNA approximately 10,000 nucleotides in length and consisting of one ORF which is encapsulated by an external lipid envelope and icosahedral capsid. HCV is a heterogeneous virus, classified into 6 genotypes and more than 50 subtypes. Because of the genome variability, nucleotide sequences of genotypes differ by approximately 31-34%, and by 20-23% among subtypes. Quasi-species of mixed virus populations provide a survival advantage for the virus to create multiple variant genomes and a high rate of generation of variants to allow rapid selection of mutants for new environmental conditions. Direct contact with infected blood and blood products, sexual relationships and availability of injectable drugs have had remarkable effects on HCV epidemiology. Hundreds of thousands of people die each year from hepatitis and liver cancer caused by HCV virus infection. Approximately 80% of patients with acute hepatitis C progress into a chronic disease state leading to serious hepatic disorders, 10-20% of which develop chronic liver cirrhosis and hepatocellular carcinoma. The incubation period of HCV is 6-8 weeks and the infection is often asymptomatic so it is very hard to detect at early stages, making early treatment very difficult. Therefore, hepatitis C is called a "silent disease". Neutralizing antibodies are produced against several HCV proteins during infection but the virus mutates to escape from antibodies. Some patients with chronic hepatitis C may have some symptoms such as fatigue, muscle aches, nausea and pain. Autoimmune and immunecomplex-mediated diseases have also been reported with chronic HCV infection.

• Journal of Korea Water Resources Association
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• v.49 no.5
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• pp.439-450
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• 2016

For the design of infrastructures controlling the flood events at ungauged basins, this study tries to find the regional flood frequencies using peak flow data generated by the spatial extension of flood records. The Chungju Dam watershed is selected to validate the possibility of regional flood frequency analysis using the spatially extended flood data. Firstly, based on the index flood method, the flood event data from the spatial extension method is evaluated for 22 mid/smaller sub-basins at the Chungju Dam watershed. The homogeneity of the Chungju dam watershed was assessed in terms of the different size of watershed conditions such as accumulated and individual sub-basins. Based on the result of homogeneity analysis, this watershed is heterogeneous with respect to individual sub-basins because of the heterogeneity of rainfall distribution. To decide the regional probability distribution, goodness-of fit measure and weighted moving averages method from flood frequency analysis were adopted. Finally, GEV distribution was selected as a representative distribution and regional quantile were estimated. This research is one step further method to estimate regional flood frequency for ungauged basins.

• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.931-937
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• 2008

Rigorous multiscale modelling and simulation of the MTR for WGSR was carried out to accurately predict the behavior of process variables and the reactor performance. The MTR consists of 4 fixed bed tube reactors packed with heterogeneous catalysts, as well as surrounding shell part for the cooling purpose. Considering that fluid flow field and reaction kinetics give a great influence on the reactor performance, employing multiscale methodology encompassing Computational Fluid Dynamics (CFD) and process modeling was natural and, in a sense, inevitable conclusion. Inlet and outlet temperature of the reactant fluid at the tube side was $345^{\circ}C$ and $390^{\circ}C$, respectively and the CO conversion at the exit of the tube side with these conditions approached to about 0.89. At the shell side, the inlet and outlet temperature of the cooling fluid, which flows counter-currently to tube flow, was $190^{\circ}C$ and $240^{\circ}C$. From this heat exchange, the energy saving was achieved for the flow at shell side and temperature of the tube side was properly controlled to obtain high CO conversion. The simulation results from this research were accurately comparable to the experimental data from various papers.

• Korean Journal of Environment and Ecology
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• v.26 no.1
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• pp.82-90
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• 2012

In this study, we investigated the environmental factors and growth characteristics of Sasa borealis community inside a temperate deciduous forest and reviewed its effect on the lower vegetation and natural regeneration. The S. borealis community in the Jungsan-ri region of Jirisan National Park was chosen as the study area, and the vegetation and the environmental factors were investigated. The dominance value, height and foliage layer thickness were investigated as the growth characteristics of S. borealis in the area. As the environmental factors, we investigated the photosynthesis photon flux density (PPFD) of the shrub and ground layers as well as the chemical characteristics of the soil. Additionally, we investigated the flora on the ground layer of the area as well as the number and height of woody plants. The result showed that the height and foliage layer thickness of the S. borealis was closely related to the light conditions but the distribution was not determined simply by the effect of the environment or vegetation of the particular area. This may be deeply related with the unique survival strategy of S. borealis, a vegetably propagated plant, that it can extensively distributed on a heterogeneous resources environment in a forest as multiple culm are interconnected with each other through the rhizomes. The dense dominance and great height of S. borealis reduced the plant species diversity in the ground layer by decreasing the PPFD on the ground surface.

• Journal of Adhesion and Interface
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• v.13 no.2
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• pp.58-63
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• 2012

CFRP chip is the byproduct from carbon fiber reinforced plastic (CFRP) processing. CFRP chip is not simply a waste mainly composed of fine carbon fiber and epoxy resin. CFRP chip keeps matrix to maximize their reinforcing effect. To obtain a uniform length of carbon fiber in CFRP chip, chip was chopped ina mortar. CFRP chip should be purified to get better interface adhesion. Epoxy resin on the carbon fiber was removed by $H_2O_2$ surface etching treatment. Optimal dispersion and fabrication conditions of CFRP chip embedded in phenolic resin were determined by thermal stability for fire retardant applications. CFRP chip-phenolic composite exhibits better mechanical and thermal properties than neat phenolic resin. Surface condition of CFRP chip-phenolic composite was evaluated by static contact angle measurement. Contact angle of CFRP chip-phenolic composite was greater than neat phenolic due to heterogeneous condition of fine carbon fibers. From the evaluation for fire retardant (ASTM D635-06) test, thermal stability of CFRP chip-phenolic composite was found to be improved with higher concentration of CFRP chip.

• Asia pacific journal of information systems
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• v.23 no.2
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• pp.67-86
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• 2013

This study first provides a stylized model that captures the essential features of the SC (Social Commerce) business and the competition process. The model focuses on the relationship between key decision issues such as marketing inputs and market value. As more SCs join the industry, they are inevitably faced with fierce competition, which may lead to sharp increase in the total marketing and advertising expenditure. This type of competition may lead the industry away from its optimal development path, and at worst, toward a disruption of the entire industry ecosystem. Such being the case, another goal of this study is to examine the possibility that the ToC (Tragedy of the Commons) may occur in the SC industry. We build game models, each of which assumes homogeneity and heterogeneity of SC providers, respectively, and derive explicit equilibrium solutions from both models. Our basic analysis presents Nash equilibria in both models and shows that SC providers are inevitably faced with fierce competition, which may lead to sharp increase in the total marketing expenses. We also compare the game outcomes with one with a hypothetical social planner who determines the total marketing level that optimizes the entire market value. Then, ToC can be defined to describe the situation where the total marketing efforts exceed the socially optimal level of marketing efforts. In both models, we examine the possibility of the ecosystem disruption and specify the conditions under which ToC may occur. However, the chance of avoiding ToC is higher with heterogeneous players than with homogeneous players. To supplement our analytical results, we develop a simulation model which incorporates a market dynamics based on the gap between actual marketing efforts and socially optimal marketing level. Simulation experiments present some lessons and insights which also confirm out findings from equilibrium analysis. For example, heterogeneity in SC providers alleviates the severity of ToC and makes it faster for survivors to escape from the ToC trap. As a result, the degree of industrial concentration tends to increase, which also explains the 'rich-get-richer' phenomenon observed in some empirical studies on the SC industry. Lastly, based on our analytical and experimental results, we come up with some measures to avoid ToC and overcome the shortcomings intrinsic to the current business model. And further discussions provide strategic implications and policy directions to overcome the possible trap of ToC in this ecosystem, and eventually help the industry to sustainably develop itself toward the next level. To name a few examples of policy measures, regulations on the marketing activities so that the overall marketing expenses cannot go beyond the socially optimal level; institutional guidelines and rules to straightening up the distortions in the way that SC providers view the marketing costs (the current marketing costs are underestimated, thereby encouraging SC providers to increase marketing expenditure); and so on.

• Journal of Science and Technology Studies
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• v.15 no.2
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• pp.263-301
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• 2015

Digital inclusion is the ability or opportunities of individuals and groups to access and use information technology (IT). Digital inclusion strategies aims to ensure that all citizens regardless of their gender, race and class benefit from IT. Discourse of digital inclusion is notable in that it proposes a desirable relationship between the state, individuals, and the market within the shifting topology of technoscience. Throughout broad discourse analysis of media coverages, in-depth interviews and reports on Korean IT industry, this research argues that dialogues on digital inclusion have substantially influenced the formation of a specific ethical regime. In this regime, individuals should become subjects embodying IT expertise and acceptable codes of conducts. We further discuss that such government-driven ethical regime conflicts with technological citizenship practiced by IT experts and semi-experts. We make theoretical contribution to STS by expanding the concept of technological citizenship to include the rights and obligations of heterogeneous expert and semi-expert groups to form, propose and socially demand alternative developmental pathways of technoscience. We also note that, amid the conflict between ethical regime and technological citizenship, alternative interpretations of gender gap can be forged, providing competing perspectives on women's under-representation and labor conditions in the IT industry. Further research is required to capture the emergence of multiple identities--differentiated by gender, race, class, and more--within the clashing interface between the ethical regime and technological citizenship.

• Solar Energy
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• v.15 no.2
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• pp.65-75
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• 1995

We have summarised some important aspects of our recent basic and applied studies in the area of photocatalytic detoxifcation with Degussa P25 titanium dioxide($TiO_2$) being the photocatalyst. Heterogeneousphotocatalytic decompositions of two components such as TCE-chloroform, TCE-phenol and TCE-benzene as well as single component organic, TCE, chloroform and $CCl_4$ were carried out to investigate the effect of additional compound on the TCE decomposition rate. In laboratory experiments, the optimum flow rate of TCE solution was $200cm^3/min$ with annular photoreactor in the presence of 0.1 wt% $TiO_2$ powder under illumination. It was observed that the second compound such as $CHCl_3$, phenol and benzene has a negative effect on the TCE decomposition rate. Result presented that TCE decomposition ratio was increased at low pH in the TCE-phenol two component solution. It could be shown that the photocatalytic reactor exhibits technical feasibility of detoxifying the multicomponent under proper experimental conditions.

• Clinical and Experimental Pediatrics
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• v.64 no.10
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• pp.504-510
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• 2021

Population screening of newborns is an extremely important and informative diagnostic approach that allows early identification of babies who are predisposed to the development of a number of serious diseases. Some of these diseases are known and have effective treatment methods. Neonatal screening enables the early diagnosis and subsequent timely initiation of therapy. This helps to prevent serious complications and reduce the percentage of disability and deaths among newborns and young children. Primary immunodeficiency diseases and primary immunodeficiency syndrome (PIDS) are a heterogeneous group of diseases and conditions based on impaired immune system function associated with developmental defects and characterized by various combinations of recurrent infections, development of autoimmune and lymphoproliferative syndromes (genetic defects in apoptosis, gene mutation Fas receptor or ligand), granulomatous process, and malignant neoplasms. Most of these diseases manifest in infancy and lead to serious illness, disability, and high mortality rates. Until recently, it was impossible to identify children with PIDS before the onset of the first clinical symptoms, which are usually accompanied by complications in the form of severe coinfections of a viral-bacterial-fungal etiology. Modern advances in medical laboratory technology have allowed the identification of children with severe PIDS, manifested by T- and/or B-cell lymphopenia and other disorders of the immune system. This review discusses the main existing strategies and directions used in PIDS screening programs for newborns, including approaches to screening based on excision of T-cell receptors and kappa-recombination excision circles, as well as the potential role and place of next-generation sequencing technology to increase the diagnostic accuracy of these diseases.