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41.
Soo-In Sohn Jae-Hyung Ahn Subramani Pandian Young-Ju Oh Eun-Kyoung Shin Hyeon-Jung Kang Woo-Suk Cho Youn-Sung Cho Kong-Sik Shin 《International journal of molecular sciences》2021,22(11)
Bacterial communities in rhizosphere and root nodules have significant contributions to the growth and productivity of the soybean (Glycine max (L.) Merr.). In this report, we analyzed the physiological properties and dynamics of bacterial community structure in rhizosphere and root nodules at different growth stages using BioLog EcoPlate and high-throughput sequencing technology, respectively. The BioLog assay found that the metabolic capability of rhizosphere is in increasing trend in the growth of soybeans as compared to the bulk soil. As a result of the Illumina sequencing analysis, the microbial community structure of rhizosphere and root nodules was found to be influenced by the variety and growth stage of the soybean. At the phylum level, Actinobacteria were the most abundant in rhizosphere at all growth stages, followed by Alphaproteobacteria and Acidobacteria, and the phylum Bacteroidetes showed the greatest change. But, in the root nodules Alphaproteobacteria were dominant. The results of the OTU analysis exhibited the dominance of Bradyrhizobium during the entire stage of growth, but the ratio of non-rhizobial bacteria showed an increasing trend as the soybean growth progressed. These findings revealed that bacterial community in the rhizosphere and root nodules changed according to both the variety and growth stages of soybean in the field. 相似文献
42.
Seungmin Ahn Hoyoung Jung Prof. Dr. Jung-Min Kee 《Chembiochem : a European journal of chemical biology》2021,22(2):319-325
Protein phosphorylation is one of the most studied post-translational modifications (PTMs). Despite the remarkable advances in phosphoproteomics, a chemically less-stable subset of the phosphosites, which we call the crypto-phosphoproteome, has remained underexplored due to technological challenges. In this Viewpoint, we briefly summarize the current understanding of these elusive protein phosphorylations and identify the missing pieces for future studies. 相似文献
43.
44.
Byung-Han Ko Sang-Geuk Jeong Young-Ghyu Ahn Kyoung-Su Park No-Cheol Park Young-Pil Park 《Microsystem Technologies》2014,20(8-9):1671-1677
Acoustic noise generated by a multi-layer ceramic capacitor (MLCC) makes users uncomfortable, so the problem must be analyzed to reduce the noise. There is a correlation between the acoustic noise and the vibration of MLCCs and the circuit board. Therefore, the acoustic noise problem must be investigated from a vibration perspective. In this study, the acoustic noise-generating mechanism was investigated, and the relationship between the characteristics of the noise and the dynamic characteristics of the circuit board with MLCC was analyzed. And a correlation criterion was proposed to predict the acoustic noise using the vibration response of the circuit board. 相似文献
45.
Gwang-Suk You Ji-Whan Ahn Gi-Chun Han Hee-Chan Cho 《Korean Journal of Chemical Engineering》2006,23(2):237-240
This study measures the neutralizing capacity of bottom ash from municipal solid waste incineration of different particle
sizes. We examine the effect of particle size on the weathering process, a method popularly used for stabilization of heavy
metals in incineration of bottom ash. The distribution of particle sizes in municipal solid waste incineration bottom ash
is rather broad, ranging from fine powder to as large as 40 mm in diameter. Although considered a by-product highly suitable
as a road construction material, the high level of heavy metal leaching is an obstacle to its reuse. Weathering, a method
used to reduce heavy metal leaching, is a lengthy process taking over thee months to complete. The chief reaction involved
in weathering is carbonation occurring between Ca(OH)2 in bottom ash and CO2(g) in the atmosphere. During this process, CaCO3 is produced, causing the pH level to drop from over 12 to about 8.2 and reducing heavy metal leaching. In this paper, we
attempt to determine the particle size best suited for reducing the period required for weathering bottom ash by identifying
characteristics of different particle sizes that affect heavy metal leaching and neutralization. 相似文献
46.
For the flexural reinforcement of bridge and building structure, synthetic materials whose dynamic properties are superior and those containing the merit of corrosion‐proof are widely used as the substitute for a steel plate. Since FRP plate has improved bond strength owing to the fibers externally adhering to the plate, many researches regarding the bond strength improvement have been substantially performed. To search out such bond strength improvement, previous researchers had ever examined the bond strength of FRP plate through their experiment by setting up many variables. However, since the experiment for a research on the bond strength takes much of expenditure for setting up the equipment and is time‐consuming, also is difficult to be carried out, it is limitedly conducted. The purpose of this study was to develop the most suitable artificial neural network model by application of various neural network models and algorithm to the data of the bond strength experiment conducted by previous researchers. Many variables were used as input layers against bond strength: depth, width, modulus of elasticity, tensile strength of FRP plate and the compressive strength, tensile strength, and width of concrete. The developed artificial neural network model has been applied back‐propagation, and its error was learned to be converged within the range of 0.001. Besides, the process for the over‐fitting problem has been dissolved by Bayesian technique. The verification on the developed model was executed by comparison with the test results of bond strength made by other previous researchers, which was never been utilized to the learning as yet. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 5119–5127, 2006 相似文献
47.
A pilot-scale sludge treatment plant was built to investigate the feasibility of ozonation processes for waste activated sludge treatment. Ozonation of wastewater sludge resulted in mass reduction by mineralization as well as by supernatant and filtrate recycle. Another advantage of sludge ozonation is a significant improvement of settleability and dewaterability. Experimental results showed that mass reduction of 70% and volume reduction of 85% compared with the control sludge was achieved through the sludge ozonation at a dose of 0.5?gO3/gDS. It is also interesting to note that the filterability deteriorates up to ozone dose of 0.2?gO3/gDS and then improves considerably at a higher ozone dose. The filterability could be improved by chemical conditioning even at a low ozone dose. The economic feasibility by cost analysis reveals that ozonation processes can be more economical than other alternative processes for sludge treatment and disposal at small-sized wastewater treatment plants. 相似文献
48.
Yeong-Kyeun Paek Jung-Ho Ahn Gyeung-Ho Kim Suk-Joong L. Kang 《Journal of the American Ceramic Society》2002,85(6):1631-1633
The densification behavior of a 3-mol%-Y2 O3 -doped ZrO2 (3Y-ZrO2 ) has been investigated under N2 and O2 atmospheres. Powder compacts have been sintered at 1550° and 1400°C for various times. The density of the specimen sintered at 1550°C is higher in N2 than in O2 , while the contrary result is obtained in the case of the specimen sintered at 1400°C. Such results can be explained in terms of nitrogen solubility and oxygen vacancy in a ZrO2 matrix. Because nitrogen solubility into the ZrO2 increases with an increase in heat-treatment temperature, leading to the formation of oxygen vacancy, the densification rate becomes higher. The present study thus shows evidence of nitrogen solubility into the ZrO2 and its role on the densification behavior of 3Y-ZrO2 . 相似文献
49.
Mercer Kelly E.; Ahn Christina E.; Coke Amanda; Compadre Cesar M.; Drake Richard R. 《Protein engineering, design & selection : PEDS》2002,15(11):903-911
Understanding the functional and mechanistic properties of themulti-substrate herpes simplex virus type-1 thymidine kinase(HSV-1 TK) remains critical to defining its role as a majorpharmacological target in herpesvirus and gene therapies forcancer. An inherent limitation of the activity of HSV-TK isthe >70-fold difference in the Kms for phosphorylation ofthymidine over the pro-drug ganciclovir (GCV). To engineer anHSV-1 TK isoform that is specific for GCV as the preferred substrate,16 site-specific mutants were generated. The mutations wereconcentrated at conserved residues involved in nucleoside basebinding, Gln125 and near sites 3 and 4 involved in catalysisand substrate binding. The substrate preferences of each mutantenzyme were compared with wild-type HSV-1 TK. One mutant, termedQ7530 TK, had a lower Km for GCV than thymidine. Expressionof the Q7530 TK in tumor cells indicated comparable metabolismto and improved sensitivity to GCV over wild-type HSV-1 TK,with minimal thymidine phosphorylation activity. A molecularmodeling simulation of the different HSV-1 TK active-sites wasdone for GCV and thymidine binding. It was concluded that mutationsat Gln125 and near site 4, especially at Ala168, were responsiblefor loss of deoxypyrimidine substrate binding. 相似文献
50.
Inorganic–organic hybrid materials for the optical waveguide were synthesized by the sol–gel process starting from the acid-catalyzed solutions of phenyltrimethoxysilane, methyltriethoxysilane, and tetraethylorthosilicate. The control of the refractive index in the organically modified silicate films was achieved by varying the content of phenyltrimethoxysilane incorporated as a refractive index modifier. A single spin-coating with the precursor solution produced a crack-free buffer layer of 22-μm thickness with a dense microstructure. For the fabrication of the patterned guiding layer on top of the buffer layer, the microfluidic lithography method was used. The patterned microlines of the linewidth of 20–35 μm with a sharp edge definition could form by filling the precursor solutions into the microchannels associated with the polydimethylsiloxane microfluidic device. The patterned guiding layer was optically transparent as similar as the bare quartz glass at the wavelength above 500 nm and had a low propagation loss of 0.77 dB/cm at 1310 nm. 相似文献