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61.
Hyung Soo Park Byung Hong Kim Hyo Suk Kim Hyung Joo Kim Gwang Tae Kim Mia Kim In Seop Chang Yong Keun Park Hyo Ihl Chang 《Anaerobe》2001,7(6):297
An obligatory anaerobic bacterium was isolated from a mediator-less microbial fuel cell using starch processing wastewater as the fuel and designated as EG3. The isolate was Gram-positive, motile and rod (2.8–3.0 μm long, 0.5–0.6 μm wide). The partial 16S rRNA gene sequence and analysis of the cellular fatty acids profile suggested that EG3 clusters with Clostridium sub-phylum and exhibited the highest similarity (98%) with Clostridium butyricum. The temperature and pH optimum for growth were 37°C and 7.0, respectively. The major products of glucose and glucose/Fe(O)OH metabolism were lactate, formate, butyrate, acetate, CO2and H2. Growth was faster at the initial phase and the cell yield was higher when the medium was supplemented with Fe(O)OH than without Fe(O)OH. These results suggest that Fe(III) ion is utilised as an electron sink. Cyclic voltammetry showed that Clostridium butyricum EG3 cells were electrochemically active. It is a novel characteristic of strict anaerobic Gram-positive bacteria. 相似文献
62.
Jeong-Nam Park Chang Pyo Han Dong-Jik Lee Seon Ah Cheon Hyun Ah Kang 《Journal of microbiology (Seoul, Korea)》2014,52(4):284-291
The hemiascomycetes yeast Yarrowia lipolytica is a dimorphic yeast with alternating yeast and mycelia forms. Bioinformatic analysis revealed the presence of three putative chitinase genes, YlCTS1, YlCTS2, and YlCTS3, in the Y. lipolytica genome. Here, we demonstrated that the protein of YlCTS1 (YlCts1p), which contains an N-terminal secretion signal peptide, a long C-terminal Ser/Thr-rich domain, and a chitin-binding domain, is a homologue to Saccharomyces cerevisiae chitinase 1 (ScCts1p). Deletion of YlCTS1 remarkably reduced extracellular endochitinase activity in the culture supernatant of Y. lipolytica and enhanced cell aggregation, suggesting a role of YlCts1p in cell separation as ScCts1p does in S. cerevisiae. However, loss of YlCts1p function did not affect hyphal formation induced by fetal bovine serum addition. The mass of YlCts1p was dramatically decreased by jack bean α-mannosidase digestion but not by PNGase F treatment, indicating that YlCts1p is modified only by O-mannosylation without N-glycosylation. Moreover, the O-glycan profile of YlCts1p was identical to that of total cell wall mannoproteins, supporting the notion that YlCts1p can be used as a good model for studying O-glycosylation in this dimorphic yeast. 相似文献
63.
Sunhee Lee Wansoo Koh Hyun‐Taek Kim Cheol‐Hee Kim Soojin Lee 《Cell biochemistry and function》2010,28(6):461-468
Cancer‐upregulated gene 2 (CUG2) was originally identified as a potential oncogene commonly up‐regulated in various human cancers. Recently, CUG2 was also identified as a new member of a centromere protein complex, important in the formation of a functional kinetochore complex. Presently, we report the pro‐apoptotic effect of CUG2 when this gene was overexpressed in the SKOV‐3 human ovarian cancer cell line. Apoptotic cell death mediated by CUG2 overexpression was independently demonstrated using cell viability determination, flow cytometry analysis, chromosome fragmentation assay, and the cleavage of the death substrate poly(ADP‐ribose) polymerase. Moreover, activation of caspase‐3 and ‐8 and the cytoplasmic translocation of mitochondrial cytochrome c were evident upon CUG2 expression. Apoptotic cell death was also observed during early development of zebrafish when CUG2 was overexpressed in zebrafish embryo. We propose that high expression of CUG2 induces apoptotic cell death. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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65.
Jung‐Gu Han Chihyun Hwang Su Hwan Kim Chanhyun Park Jonghak Kim Gwan Yeong Jung Kyungeun Baek Sujong Chae Seok Ju Kang Jaephil Cho Sang Kyu Kwak Hyun‐Kon Song Nam‐Soon Choi 《Liver Transplantation》2020,10(20)
High‐capacity Li‐rich layered oxide cathodes along with Si‐incorporated graphite anodes have high reversible capacity, outperforming the electrode materials used in existing commercial products. Hence, they are potential candidates for the development of high‐energy‐density lithium‐ion batteries (LIBs). However, structural degradation induced by loss of interfacial stability is a roadblock to their practical use. Here, the use of malonic acid‐decorated fullerene (MA‐C60) with superoxide dismutase activity and water scavenging capability as an electrolyte additive to overcome the structural instability of high‐capacity electrodes that hampers the battery quality is reported. Deactivation of PF5 by water scavenging leads to the long‐term stability of the interfacial structures of electrodes. Moreover, an MA‐C60‐added electrolyte deactivates the reactive oxygen species and constructs an electrochemically robust cathode‐electrolyte interface for Li‐rich cathodes. This work paves the way for new possibilities in the design of electrolyte additives by eliminating undesirable reactive substances and tuning the interfacial structures of high‐capacity electrodes in LIBs. 相似文献
66.
Seok Hyun Song Moses Cho Inchul Park Jong‐Gyu Yoo Kyung‐Tae Ko Jihyun Hong Jongsoon Kim Sung‐Kyun Jung Maxim Avdeev Sungdae Ji Seongsu Lee Joona Bang Hyungsub Kim 《Liver Transplantation》2020,10(23)
Layered lithium–nickel–cobalt–manganese oxide (NCM) materials have emerged as promising alternative cathode materials owing to their high energy density and electrochemical stability. Although high reversible capacity has been achieved for Ni‐rich NCM materials when charged beyond 4.2 V versus Li+/Li, full lithium utilization is hindered by the pronounced structural degradation and electrolyte decomposition. Herein, the unexpected realization of sustained working voltage as well as improved electrochemical performance upon electrochemical cycling at a high operating voltage of 4.9 V in the Ni‐rich NCM LiNi0.895Co0.085Mn0.02O2 is presented. The improved electrochemical performance at a high working voltage at 4.9 V is attributed to the removal of the resistive Ni2+O rock‐salt surface layer, which stabilizes the voltage profile and improves retention of the energy density during electrochemical cycling. The manifestation of the layered Ni2+O rock‐salt phase along with the structural evolution related to the metal dissolution are probed using in situ X‐ray diffraction, neutron diffraction, transmission electron microscopy, and X‐ray absorption spectroscopy. The findings help unravel the structural complexities associated with high working voltages and offer insight for the design of advanced battery materials, enabling the realization of fully reversible lithium extraction in Ni‐rich NCM materials. 相似文献
67.
68.
Young Moon Choi Byoung Wan Lee Myung Sun Jung Hyun Soo Han Suk Hyun Kim Kaifeng Chen Dong Ha Kim Tony F. Heinz Shanhui Fan Jihye Lee Gi‐Ra Yi Jung Kyu Kim Jong Hyeok Park 《Liver Transplantation》2020,10(22)
N‐type metal oxides such as hematite (α‐Fe2O3) and bismuth vanadate (BiVO4) are promising candidate materials for efficient photoelectrochemical water splitting; however, their short minority carrier diffusion length and restricted carrier lifetime result in undesired rapid charge recombination. Herein, a 2D arranged globular Au nanosphere (NS) monolayer array with a highly ordered hexagonal hole pattern (hereafter, Au array) is introduced onto the surface of photoanodes comprised of metal oxide films via a facile drying and transfer‐printing process. Through plasmon‐induced resonance energy transfer, the Au array provides a strong electromagnetic field in the near‐surface area of the metal oxide film. The near‐field coupling interaction and amplification of the electromagnetic field suppress the charge recombination with long‐lived photogenerated holes and simultaneously enhance the light harvesting and charge transfer efficiencies. Consequently, an over 3.3‐fold higher photocurrent density at 1.23 V versus reversible hydrogen electrode (RHE) is achieved for the Au array/α‐Fe2O3. Furthermore, the high versatility of this transfer printing of Au arrays is demonstrated by introducing it on the molybdenum‐doped BiVO4 film, resulting in 1.5‐fold higher photocurrent density at 1.23 V versus RHE. The tailored metal film design can provide a potential strategy for the versatile application in various light‐mediated energy conversion and optoelectronic devices. 相似文献
69.
Hong‐Joon Yoon Minki Kang Wanchul Seung Sung Soo Kwak Jihye Kim Hyoung Taek Kim Sang‐Woo Kim 《Liver Transplantation》2020,10(25)
Direct conversion of mechanical energy into direct current (DC) by triboelectric nanogenerators (TENGs) is one of the desired features in terms of energy conversion efficiency. Although promising applications have been reported using the triboelectric effect, effective DC generating TENGs must be developed for practical purposes. Here, it is reported that continuous DC generation within a TENG itself, without any circuitry, can be achieved by triggering air breakdown via triboelectrification. It is demonstrated that DC generation occurs in combination with i) charge accumulation to generate air breakdown, ii) incident discharge (microdischarge), and iii) conveyance of charges to make the device sustainable. 10.5 mA m?2 of output current and 10.6 W m?2 of output power at 33 MΩ load resistance are achieved. Compared to the best DC generating TENGs ever reported, the TENG in this present study generates about 20 times larger root‐mean square current density. 相似文献
70.
Qun Fan Pengfei Hou Changhyeok Choi Tai‐Sing Wu Song Hong Fang Li Yun‐Liang Soo Peng Kang Yousung Jung Zhenyu Sun 《Liver Transplantation》2020,10(5)
Electrochemical reduction of carbon dioxide (CO2) to fuels and value‐added industrial chemicals is a promising strategy for keeping a healthy balance between energy supply and net carbon emissions. Here, the facile transformation of residual Ni particle catalysts in carbon nanotubes into thermally stable single Ni atoms with a possible NiN3 moiety is reported, surrounded with a porous N‐doped carbon sheath through a one‐step nanoconfined pyrolysis strategy. These structural changes are confirmed by X‐ray absorption fine structure analysis and density functional theory (DFT) calculations. The dispersed Ni single atoms facilitate highly efficient electrocatalytic CO2 reduction at low overpotentials to yield CO, providing a CO faradaic efficiency exceeding 90%, turnover frequency approaching 12 000 h?1, and metal mass activity reaching about 10 600 mA mg?1, outperforming current state‐of‐the‐art single atom catalysts for CO2 reduction to CO. DFT calculations suggest that the Ni@N3 (pyrrolic) site favors *COOH formation with lower free energy than Ni@N4, in addition to exothermic CO desorption, hence enhancing electrocatalytic CO2 conversion. This finding provides a simple, scalable, and promising route for the preparation of low‐cost, abundant, and highly active single atom catalysts, benefiting future practical CO2 electrolysis. 相似文献