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71.
Kim HW Chung CW Kim SS Kim YB Rhee YH 《International journal of biological macromolecules》2002,30(2):129-135
Poly(3-hydroxyoctanoate) (PHO) films were treated with plasma of different discharge powers (10-50 W) and then treated with acryl amide solutions in order to prepare films with surfaces that contained different amounts of amide groups. The surfaces were characterized by contact angle measurement, attenuated total reflectance infrared spectroscopy, electron spectroscopy for chemical analysis, and scanning electron microscopy. Results from all these measurements indicated that amide groups were present on the surfaces. The amount of amide groups increased in proportion to the discharge power of the plasma. The interaction of Chinese hamster ovary cells with these grafted surfaces was investigated. The number of cells that adhered to and grew on the surfaces was highest for films grafted at 30 W of plasma discharge power, indicating that the moderate hydrophilicity was optimal for cells to adhere and grow. The present results support the suggestion that acryl amide-grafted PHO could be used as cell-compatible biomedical applications. 相似文献
72.
Yun-Hee Song Kyung-Tai Lee Jin-Young Baek Min-Ju Kim Mi-Ra Kwon Young-Joo Kim Mi-Rim Park Haesu Ko Jin-Sung Lee Keun-Sung Kim 《Folia microbiologica》2017,62(3):175-181
This study aimed to isolate and characterize a novel cellulolytic enzyme from black goat rumen by using a culture-independent approach. A metagenomic fosmid library was constructed from black goat rumen contents and screened for a novel cellulase. The KG37 gene encoding a protein of 858 amino acid residues (92.7 kDa) was isolated. The deduced protein contained a glycosyl hydrolase family 74 (GH74) domain and showed 77% sequence identity to two endo-1,4-β-glucanases from Fibrobacter succinogenes. The novel GH74 cellulase gene was overexpressed in Escherichia coli, and its protein product was functionally characterized. The recombinant GH74 cellulase showed a broad substrate spectrum. The enzyme exhibited its optimum activity at pH 5.0 and temperature range of 20–50 °C. The enzyme was thermally stable at pH 5.0 and at a temperature of 20–40 °C. The novel GH74 cellulase can be practically exploited to convert lignocellulosic biomass to value-added products in various industrial applications in future. 相似文献
73.
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
74.
Hwa‐Eun Lee Su Jung Hong Najmul Hasan Eun Joo Baek Jun Tae Kim Young‐Duk Kim Mi‐Kyung Park 《Entomological Research》2020,50(9):450-459
This study was conducted to investigate the repellent efficacy of essential oils (Origanum vulgare, Pimpinella anisum, and Tanacetum cinerariifolium) and four plant extracts (Agastache rugosa, Capsicum annuum, Citrus reticulata, and Ginkgo biloba) against Tribolium castaneum (adults and larvae) and Plodia interpunctella (larvae). Gas chromatography/mass spectrometry analysis revealed the presence of carvacrol, anethole, and jasmolin I as the predominant constituent in O. vulgare, P. anisum, and T. cinerariifolium, respectively. Furthermore, ethyl hexopyranoside, 9,12‐octadecadienoic acid, cyclopentanol, and 2‐cresol were identified in A. rugosa, C. annuum, C. reticulata, and G. biloba, respectively. The repellent efficacy of each essential oil, plant extract, and the combination of oils was evaluated using a specially designed cylinder trap for 120 h. Among the three oils, O. vulgare and T. cinerariifolium had greatest repellent efficacy against P. interpunctella larvae. T. cinerariifolium exhibited effective repellence against the adults and larvae of T. castaneum. Therefore, O. vulgare (O) and T. cinerariifolium (T) were selected for further investigation of combined effects. Two essential oils were mixed in three different ratios of OT1 (1:3), OT2 (1:1), and OT3 (3:1). The repellent efficacies of OT1 and OT2 against the adults of T. castaneum were significantly greater than that of OT3. OT1 was effective against the larvae of T. castaneum, whereas OT2 was effective against the larvae of P. interpunctella. OT1 enhanced the repellent efficacy by approximately five times against larvae of T. castaneum, compared with that of T. cinerariifolium. Overall, OT1 was selected as the best repellent substance against all the tested insects. 相似文献
75.
The life history traits of the caddisfly, Psilotreta locumtenens Botosaneanu (Odontoceridae), were studied in two stream reaches with different thermal ranges (main and branch streams) of the Gapyeong Stream, a typical mountain stream located in the central Korean Peninsula. Psilotreta locumtenens larvae were quantitatively sampled monthly from November 2008 to July 2010, and biweekly during the emergence period (late April to early July), using a Surber sampler (30 × 30 cm). Adults were quantitatively sampled with a sweep net. Larval density in the main stream (324.21 ± 38.59 m?2) was higher than that in the branch stream (60.48 ± 10.86 m?2). The larvae hatched in the early summer and overwintered as 5th and 3rd instars in the main and branch streams, respectively. The emergence peak at the main stream was approximately 2 weeks earlier. The sex ratio at both sites was approximately 0.3. The life history in both streams was univoltine. Secondary production in the main stream was much higher than in the branch stream, owing to high larval densities, and the P/B ratios at the two sites were similar. This study demonstrated remarkable differences in larval growth patterns and emergence peaks in P. locumtenens between the two stream reaches due to differences in accumulated degree days (230.30 DD) and other phenological cues such as daily mean threshold water temperature (9°C) during the ascending phase, despite their relatively small mean annual water temperature difference of 0.58°C. 相似文献
76.
The mass cultivation of Ecklonia stolonifera Okamura was studied as a possible summer feed for the abalone industry in Korea for the period between August and November
when Undaria and Laminaria are not available. Experiments were conducted to investigate the optimal conditions for artificial seed production and mass
cultivation of this species. Seedlings of E. stolonifera were reared in an indoor tank for 60 days until they were around 500 μm in length. Following indoor tank culture, the seedlings
were transferred in situ to a nursery culture area for 2 months, before begin transferred to the main grow-out area. The maximum growth and development
of young thalli in nursery culture area occurred at 2 m depth, whilst maximum growth of thalli in the main culture area occured
at 1.5 m depth. Production of E. stolonifera was between 3 and 9 kg wet wt. m−1 in the first year of culture after seeding and 12 to 13 kg wet wt. m−1 in the second year of culture, after management (depth control and fouling organism removal, etc.) of the holdfast. The relationship
between optimal water depth for culture and underwater irradiance during the E. stolonifera cultivation was defined as: y = −0.331x + 8.198 (r
2 = 0.9903). The growth rates achieved in this trial indicate that E. stolonifera cultures could produce sufficient biomass to supply summer feed for the Korean abalone industry. 相似文献
77.
Lee WS Lee DW Baek YI An S An SJ Cho KH Choi YK Kim HC Park HY Bae KH Jeong TS 《Bioorganic & medicinal chemistry letters》2004,14(12):3109-3112
The sesquineolignan, saucerneol B (1), and dineolignans, manassantin A (2), and manassantin B (3), were isolated from the methanol extracts of Saururus chinensis root and elucidated by their spectroscopic data analysis. Compounds 1-3 inhibited hACAT-1 and hACAT-2 with IC(50) values of 43.0 and 124.0 microM for 1, of 39.0 and 8.0 microM for 2, of 82.0 microM and only 32% inhibition at 1mM for 3, respectively. The EtOAc-soluble fraction, which contained compounds 1-3, of methanol extracts of S. chinensis exhibited strong cholesterol-lowering effect in high cholesterol-fed mice. 相似文献
78.
Length‐weight relationships for 18 freshwater fish species from the Nakdong River in South Korea 下载免费PDF全文
J.‐W. Lee J.‐D. Yoon J.‐H. Kim S.‐H. Park S.‐H. Baek J.‐J. Yu M.‐H. Jang J.‐I. Min 《Zeitschrift fur angewandte Ichthyologie》2015,31(3):576-577
Length‐weight relationships of 18 freshwater fish species from the Nakdong River in South Korea are presented. Length‐weight relationship data for 10 of these species were not available previously. 相似文献
79.
Cha CY Earm KH Youm JB Baek EB Kim SJ Earm YE 《Progress in biophysics and molecular biology》2008,96(1-3):399-420
In vascular smooth muscle cells, it has been suggested that membrane potential is an important component that initiates contraction. We developed a mathematical model to elucidate the quantitative contributions of major ion currents [a voltage-gated L-type Ca2+ current (ICaL), a voltage-sensitive K+ current (IKV), a Ca2+-activated K+ current (IKCa) and a nonselective cation current (INSC)] to membrane potential. In order to typify the diverse nature of pulmonary artery smooth muscle cells (PASMCs), we introduced parameters that are not fixed (variable parameters). The population of cells with different parameters was constructed and the cells that have the electrophysiological properties of PASMCs were selected. The contributions of each membrane current were investigated by sensitivity analysis and modification of the current parameters. Consequently, IKV and INSC were found to be the most important currents that affect the membrane potential. The occurrence of depolarisation in hypoxic pulmonary vasoconstriction (HPV) was also examined. In hypoxia, IKV and IKCa were reduced, but the consequent depolarisation in simulation was not enough to initiate contractions. If we add an increase of INSC (2.5-fold), the calculated membrane potential was enough to induce contraction. From the results, we conclude that the balance of various ion channel activities determines the resting membrane potential of PASMCs and our model was successful in explaining the depolarisation in HPV. Therefore, this model can be a powerful tool to investigate the various electrical properties of PASMCs in both normal and pathological conditions. 相似文献
80.
Anna G. U. S. Newcomb Seungwon Baek Brian P. Kelly 《Computer methods in biomechanics and biomedical engineering》2017,20(2):182-192
Angled screw insertion has been advocated to enhance fixation strength during posterior spine fixation. Stresses on a pedicle screw and surrounding vertebral bone with different screw angles were studied by finite element analysis during simulated multidirectional loading. Correlations between screw-specific vertebral geometric parameters and stresses were studied. Angulations in both the sagittal and axial planes affected stresses on the cortical and cancellous bones and the screw. Pedicle screws pointing laterally (vs. straight or medially) in the axial plane during superior screw angulation may be advantageous in terms of reducing the risk of both screw loosening and screw breakage. 相似文献