• Carbon letters
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• v.22
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• pp.1-13
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• 2017

Porous materials play a vital role in science and technology. The ability to control their pore structures at the atomic, molecular, and nanometer scales enable interactions with atoms, ions and molecules to occur throughout the bulk of the material, for practical applications. Three-dimensional (3D) porous carbon-based materials (e.g., graphene aerogels/hydrogels, sponges and foams) made of graphene or graphene oxide-based networks have attracted considerable attention because they offer low density, high porosity, large surface area, excellent electrical conductivity and stable mechanical properties. Water pollution and associated environmental issues have become a hot topic in recent years. Rapid industrialization has led to a massive increase in the amount of wastewater that industries discharge into the environment. Water pollution is caused by oil spills, heavy metals, dyes, and organic compounds released by industry, as well as via unpredictable accidents. In addition, water pollution is also caused by radionuclides released by nuclear disasters or leakage. This review presents an overview of the state-of-the-art synthesis methodologies of 3D porous graphene materials and highlights their synthesis for environmental applications. The various synthetic methods used to prepare these 3D materials are discussed, particularly template-free self-assembly methods, and template-directed methods. Some key results are summarized, where 3D graphene materials have been used for the adsorption of dyes, heavy metals, and radioactive materials from polluted environments.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.453-460
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• 2011

Recently, there is growing interests in the application of supercritical fluids for food and medical fields since supercritical fluids ($CO_2$ and $N_2O$) have known to be safe and effective as a non-thermal sterilization technique. Although supercritical fluids have been investigated for various kinds of products, they have not yet been used in common currency due to their lack of knowledge related to the antimicrobial activity or detailed mechanisms. In this review paper, we summarized the characteristics, antimicrobial activity and mechanisms, important factors, and applicability of supercritical fluids to help the investigation and commercialization of supercritical fluids sterilization technique.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.2
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• pp.163-166
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• 2018

Objective: Microminipigs are a novel animal model with extensive applications in laboratory studies owing, in part, to their extremely small body sizes. In this study, the relationship between swine leukocyte antigen (SLA) class II haplotype and body weight was evaluated in the Microminipig population. Methods: A total of 1,900 haplotypes, covering SLA class II haplotypes Lr-0.7, Lr-0.23, Lr-0.17, Lr-0.37, Lr-0.16, Lr-0.11, Lr-0.13, and Lr-0.18, were analyzed in 950 piglets. Birth weights and weights on postnatal day 50 were examined in piglets with eight different SLA class II haplotypes. Results: The mean birth weight of piglets with the Lr-0.23 haplotype (0.415 kg, n = 702) was significantly lower than that of piglets with Lr-0.17 (0.445 kg, n = 328) and Lr-0.37 (0.438 kg, n = 383) haplotypes. At postnatal day 50, the mean body weight of piglets with the Lr-0.23 haplotype (3.14 kg) was significantly lower than that of piglets with the Lr-0.13 haplotype (3.46 kg, p<0.01). There were no significant differences in daily gains (DGs) among the eight haplotypes. However, piglets with the Lr-0.11 and -0.18 haplotype combination or any heterozygous haplotype combinations containing Lr-0.23 had significantly lower DGs than those of piglets with the Lr-0.18, 0.37 haplotype combination. Conclusion: Piglets with the Lr-0.23 haplotype had relatively low body weights at birth and on postnatal day 50 and slightly lower DGs than those of piglets with other haplotypes. Therefore, the Lr-0.23 SLA class II haplotype may be a suitable marker for the selective breeding of Microminipigs with small body sizes.

• Animal cells and systems
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• v.3 no.4
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• pp.359-363
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• 1999

Urochordates, the most primitive group in phylum Chordata, are mostly sessile as adults although some are free living. Presently, the ancestral stock of urochordates as weir as chordates has been the focus of interest and two conflicting hypotheses have been presented. A free swimming ancestor is one and a sessile, filter feeding ancestor is the other. To clarify the phylogenetic relationships within the urochordates, 22 urochordates and five others as outgroups were used. And we applied neighbor joining, maximum likelihood, and maximum parsimony methods to partial 18S rDNA sequences. The inferred phylogeny in all analyses indicates that order Aplousobranchia of class Ascidiacea appears to be the most ancestral group among urochordates. But it is not clear for the low bootstrap value. The remaining two orders of ascidians, Phlebobranchia and Stolidobranchia, form monophyletic groups respectively, which are well supported by high bootstrap values. These two orders are closer to classes of Thaliacea and Appendicularia than to the Aplousobranchia. While class Appendicularia is strongly supported by the monophyletic group, the phylogenetic position of class Thaliacea is unclear in this study.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.71-71
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• 2011

Dye-sensitized solar cells (DSCs) have drawn great academic attention due to their potential as low-cost renewable energy sources. DSCs contain a nanostructured TiO2 photoanode, which is a key-component for high conversion efficiency. Particularly, one-dimensional (1-D) nanostructured photoanodes can enhance the electron transport for the efficient collection to the conducting substrate in competition with the recombination processes. This is because photoelectron colletion is determined by trapping/detrapping events along the site of the electron traps (defects, surface states, grain boundaries, and self-trapping). Therefore, 1-D nanostructured photoanodes are advantageous for the fast electron transport due to their desirable features of greatly reduced intercrystalline contacts with specified directionality. In particular, anodic TiO2 nanotube (NT) electrodes recently have been intensively explored owing to their ideal structure for application in DSCs. Besides the enhanced electron transport properties resulted from the 1-D structure, highly ordered and vertically oriented nanostructure of anodic TiO2 NT can contribute additional merits, such as enhanced electrolyte diffusion, better interfacial contact with viscous electrolytes. First, to confirm the advantages of 1-D nanostructured material for the photoelectron collection, we compared the electron transport and charge recombination characteristics between nanoparticle (NP)- and nanorod (NR)-based photoanodes in DSCs by the stepped light-induced transient measurements of photocurrent and voltage (SLIM-PCV). We confirmed that the electron lifetime of the NR-based photoanode was much longer than that of the NP-based photoanode. In addition, highly ordered and vertically oriented TiO2 NT photoanodes were prepared by electrochemical anodization method. We compared the photovoltaic properties of DSCs utilizing TiO2 NT photoanodes prepared by one-step anodization and two-step anodization. And, to reduce the charge recombination rate, energy barrier layer (ZnO, Al2O3)-coated TiO2 NTs also applied in DSC. Furthermore, we applied the TiO2 NT photoanode in DSCs using a viscous electrolyte, i.e., cobalt bipyridyl redox electrolyte, and confirmed that the pore structure of NT array can enhance the performances of this viscous electrolyte.

• Clean Technology
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• v.16 no.3
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• pp.220-228
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• 2010

Four Keggin-type heteropolyacids, $H_nXM_{12}O_{40}$(X = P and Si, M = W and Mo) that were substituted with heteroatom and polyatom were applied to the dehydration reaction of fructose to 5-hydroxymethylfurfural (HMF). The results showed that the acid became stronger when the heteroatom and polyatom were substituted with P and W than the cases of Si and Mo, respectively. However, the amount of acidic sites increased with the decrease in the acid strength, resulting in the change of the catalytic activity of heteropolyacids in the dehydration reaction. The experimental results revealed that four different heteropolyacids produced similar amounts of HMF via the dehydration reaction of fructose due to the counterbalancing effect between the amount of active sites, which is related to the catalytic activity of heteropolyacids, and the softness of polyanion. In addition, it was observed that the prepared heteropolyacids showed good structural stability after heat treatment at $200^{\circ}C$.

• Journal of Species Research
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• v.10 no.3
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• pp.301-320
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• 2021

During a field survey of indigenous Korean ciliates, we collected 21 unrecorded species from aquatic (freshwater and brackish water [salinity about 1.0‰] samples) and terrestrial(moss and soil samples) habitats. The morphology of these species was studied based on live observation, protargol, silver carbonate and silver nitrate impregnation, and scanning electron microscope. These species belong to seven classes as follows: 1) class Heterotrichea - Blepharisma seculum; 2) class Spirotrichea - Birojimia terricola, Bistichella variabilis, Deviata bacilliformis, Oxytricha paragranulifera, Parabistichella cf. variabilis, Steinia sphagnicola, Stichotricha aculeata, Stylonychia cf. notophora, and Tetmemena bifaria minima; 3) class Armophorea - Metopus es; 4) class Litostomatea - Acropisthium mutabile, Pseudomonilicaryon japonicum, and Rimaleptus alpinus; 5) class Phyllopharyngea - Podophrya bivacuolata; 6) class Nassophorea - Drepanomonas pauciciliata; and 7) class Oligohymenophorea - Dexiostoma campylum, Frontonia atra, Histiobalantium natans viridis, Opisthonecta minima, and Tetrahymena rostrata. Here, we provide a brief diagnosis and remark for each species.

• Korean Journal of Biological Psychiatry
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• v.1 no.1
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• pp.79-87
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• 1994

For the purpose of evaluating the human leukocyte antigen(HLA) disease-association with bipolar disorder, HLA class I and class II allelic frequencies were assessed in 37 bipolar patients and were compared to the data from normal population. HLA class 1 typing was performed with microlymphocytotoxicity method while class II(DRB1) genotyping with reverse dot blot hybridization and sandwich method. Statistical analysis consisted of relative risk, Haldane's modified relative risk, Fisher's exact test and Bonferoni's corrected P. The results were as follows : 1) Bipolar patients showed increased allelic frequency of HLA A3 which has statistical significance. 2) Allelic frequencies of HLA B7, B14 and B54 were higher, while those of B51 and B55 were lower in bipolar patients, but they were not statistically significant. 3) Both of increased frequencies of DR2 in bipolar patients and DR15 in normal controls had statistical significance. The results of the present study suggested that some of HLA allelic types might be associated with bipolar disorder. To clarify the genetic influence of HLA to bipolar disorder, we should do consecutive study of bipolar disorder with new information about HLA system including alleles.

• Korean Journal of Environmental Biology
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• v.38 no.2
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• pp.289-298
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• 2020

As part of the research program "2018 Rapid screening and identification of freshwater microorganisms using MALDI-TOF/MS library" freshwater samples were collected from a branch of the Nakdong River. Almost 300 antibiotic-resistant bacterial strains were isolated from freshwater samples and subsequently identified by 16S rRNA gene sequencing. Seventeen strains among the isolates shared high 16S rRNA gene sequence similarity (>99.0%) with known species that were not previously recorded in Korea, and each of the isolates also formed a robust phylogenetic clade with the closest species. These species were phylogenetically diverse, belonging to four phyla, seven classes, 10 orders, and 13 genera. At the genus and class level, the previously unrecorded species belonged to Rhodovarius, Xanthobacter, and Shinella of the class Alphaproteobacteria; Ottowia, Simplicispira, and Zoogloea of Betaproteobacteria; Pseudomonas, Acinetobacter, and Shewanella of Gammaproteobacteria; Arcobacter of Epsilonproteobacteria; Sphingobacterium of Sphingobacteriia; Trichococcus of Bacilli; and Leucobacter of Actinobacteria. The previously unrecorded species were further characterized by examining their gram-staining, colony and cell morphology, biochemical properties, and phylogenetic position.

• Journal of Korean Biological Nursing Science
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• v.19 no.4
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• pp.227-240
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• 2017

Purpose: The purpose of this review was to identify the current status of nursing studies on heart failure (HF) patients in South Korea and to suggest future study direction. Methods: A literature review of databases such as KoreaMed, KERIS and nursing and allied health journal were searched with key terms 'heart failure' and 'nursing' for the period from January 2000 to February 2017. A total of 35 studies including 28 articles and 7 theses met the inclusion criteria. Results: Twenty-seven out of 35 studies were observational studies on outpatients and most of the studies did not mention the ejection fraction and New York Heart Association functional classification class (NYHA class) in the inclusion criteria. Self-care and health-related quality of life as psychological factors, and physical activity as a biological factor, were used as main variables. However, we found it difficult to understand how much score indicates better quality of life because of an inconsistent and wide score. In quality assessment, 8 intervention studies had no serious flaws. Conclusion: Further studies should consider more biological and social factors influencing HF. The quality assessment with respect to nursing intervention studies in HF showed that randomized and double-blind trials are needed.