• Korean Journal of Microbiology
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• v.54 no.1
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• pp.84-86
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• 2018

Cells of Deinococcus puniceus $DY1^T$ are Gram-positive, coccus-shaped, and crimson color-pigmented. Strain $DY1^T$ was isolated from soil irradiated with 5 kGy gamma radiation and showed resistance to UVC and gamma radiation. In this study, we report the complete genome sequence of a bacterium Deinococcus puniceus $DY1^T$ is consist of circular chromosome comprised of 2,971,983 bp, with the G + C content of 62.5%. The complete genome sequence was obtained using the PacBio RS II platform, it included 2,617 coding sequences (CDs), 2,762 genes, and 88 pseudogene.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.315-318
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• 1994

To obtain transformed plants, we cocultured cotyledonary explants of Codonopsis lanceolata with Agrobacterium tumefaciens LBA4404, a disamed strain harboring a binary vector pBI121 carrying the CaMV35S promoter-$\beta$-glucuronidase (GUS) gene fusion used as a reporter gene and NOS promoter-neomycin phosphotransferase gene as a positive selection marker in MS liquid medium with 1mg/L BA. After 48 h of culture, explants were transferred onto MS solid medium with Img/L BA, 250mg/L carbenicillin, and 100mg/L kanamycin sulfate and cultured in the dark. Numerous adventitious buds formed on the cut edges of the explants after 2 weeks of culture. When subjected to GUS histochemical assay buds showed a positive response at a frequency of 15%. Explants formed adventitious shoot at a frequency of 56.7%, after 6 weeks of culture. Upon transfer onto the basal medium, most of the shoots were rooted and subsequently the regenerants were transplanted to potting soil. Southern blot analysis confirmed that the GUS gene was incorporated into the genomic DNA of the GUS-positive regenerants.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.963-978
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• 2020

Earthquakes can induce a large number of landslides and cause very serious property damage and human casualties. There are two issues in study on earthquake-induced landslides: (1) slope stability analysis under seismic loading and (2) debris flow run-out analysis. This study aims to review technical studies related to the development and application of earthquake-induced landslide models (seismic slope stability analysis). Moreover, a pilot application of a physics-based slope stability model to Mt. Umyeon, in Seoul, with several earthquake scenarios was conducted to test regional scale seismic landslide mapping. The earthquake-induced landslide simulation model can be categorized into 1) Pseudo-static model, 2) Newmark's dynamic displacement model and 3) stress-strain model. The Pseudo-static model is preferred for producing seismic landslide hazard maps because it is impossible to verify the dynamic model-based simulation results due to lack of earthquake-induced landslide inventory in Korea. Earthquake scenario-based simulation results show that given dry conditions, unstable slopes begin to occur in parts of upper areas due to the 50-year earthquake magnitude; most of the study area becomes unstable when the earthquake frequency is 200 years. On the other hand, when the soil is in a wet state due to heavy rainfall, many areas are unstable even if no earthquake occurs, and when rainfall and 50-year earthquakes occur simultaneously, most areas appear unstable, as in simulation results based on 100-year earthquakes in dry condition.

• Geomechanics and Engineering
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• v.29 no.1
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• pp.25-40
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• 2022

In this study, 3D coupled-consolidation numerical parametric study was conducted to predict the deformation mechanism of a 20 storey building sitting on (4×4) piled raft (with length of piles, L_p=30 m) to adjacent 6 m diameter (D) tunnelling in stiff clay. The influences of different tunnel locations relative to piles (i.e., z_t/L_p) were investigated in this parametric study. In first case, the tunnel was excavated near the pile shafts with depth of tunnel axis (z_t) of 9 m (i.e., z_t/L_p). In second and third cases, tunnels were driven at z_t of 30 m and 42 m (i.e., z_t/L_p = 1.0 and 1.4), respectively. An advanced hypoplastic clay model (which is capable of taking small-strain stiffness in account) was adopted to capture soil behaviour. The computed results revealed that tunnelling activity adjacent to a building resting on piled raft caused significant settlement, differential settlement, lateral deflection, angular distortion in the building. In addition, substantial bending moment, shear forces and changes in axial load distribution along pile length were induced. The findings from the parametric study revealed that the building and pile responses significantly influenced by tunnel location relative to pile.

• Microbiology and Biotechnology Letters
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• v.50 no.4
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• pp.501-507
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• 2022

PET (Polyethylene terephthalate), a representative plastic material, has useful physicochemical properties such as high durability and economic feasibility, and is used in various industrial fields such as bottles, fibers, and containers. Due to the recent increase in plastic usage including disposable products, eco-friendly strategy using microorganisms have drawn attention differentiated from conventional landfill and incineration methods. In this study, a soil-derived Streptomyces javensis Inha503 containing a PETase gene was selected and the ability to hydrolyze PU (Polyurethane) was confirmed through agar plate diffusion assay. This strain was cultured with PET for a month, and PET decomposition ability was also confirmed through a scanning electron microscope. Moreover, cloning and heterologous expression of S. javensis Inha503 PETase gene exhibited PET activity in the PETase non-containing S. coelicolor, confirming for the first time the presence of functional PETase gene in Streptomyces species.

• The Plant Pathology Journal
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• v.39 no.5
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• pp.430-448
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• 2023

Recently, strategies for controlling Fusarium oxysporum f. sp. lycopersici (Fol), the causal agent of Fusarium wilt of tomato, focus on using effective biocontrol agents. In this study, an analysis of the biocontrol and plant growth promoting (PGP) attributes of 11 isolates of loamy soil Bacillus spp. has been conducted. Among them, the isolates B.PNR1 and B.PNR2 inhibited the mycelial growth of Fol by inducing abnormal fungal cell wall structures and cell wall collapse. Moreover, broad-spectrum activity against four other plant pathogenic fungi, F. oxysporum f. sp. cubense race 1 (Foc), Sclerotium rolfsii, Colletotrichum musae, and C. gloeosporioides were noted for these isolates. These two Bacillus isolates produced indole acetic acid, phosphate solubilization enzymes, and amylolytic and cellulolytic enzymes. In the pot experiment, the culture filtrate from B.PNR1 showed greater inhibition of the fungal pathogens and significantly promoted the growth of tomato plants more than those of the other treatments. Isolate B.PNR1, the best biocontrol and PGP, was identified as Bacillus stercoris by its 16S rRNA gene sequence and whole genome sequencing analysis (WGS). The WGS, through genome mining, confirmed that the B.PNR1 genome contained genes/gene cluster of a nonribosomal peptide synthetase/polyketide synthase, such as fengycin, surfactin, bacillaene, subtilosin A, bacilysin, and bacillibactin, which are involved in antagonistic and PGP activities. Therefore, our finding demonstrates the effectiveness of B. stercoris strain B.PNR1 as an antagonist and for plant growth promotion, highlighting the use of this microorganism as a biocontrol agent against the Fusarium wilt pathogen and PGP abilities in tomatoes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.2
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• pp.187-195
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• 2022

This study investigated the effect of artesian pressure on mechanical properties of deep cement mixing (DCM)-improved specimens. Various laboratory tests such as unconfined compression test and scanning electron microscope (SEM) were conducted on DCM specimens which curied in a water tank with different artesian pressures. The artesian pressure was determined in consideration of the laboratory scale and the hydraulic gradient in field conditions. Results of experimental tests indicated that unconfined compressive strength, secant modulus, and unit weight of specimen decreased and water content tended to increase as an artesian pressure increased. The stress-strain behavior changed brittle to ductile behaviors as an artesian pressure increased. The outflow water from the water tank reacted with the phenolphthalein solution due to the leaching phenomenon of the improved specimen. SEM analysis also confirmed that a small amount of ettringite was formed between soil particles in the specimens with artesian pressure.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6C
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• pp.349-358
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• 2008

In performing the reliability analysis for predicting the settlement with time of alluvial clay layer at Kobe airport, the uncertainties of geotechnical properties were examined based on the stochastic and probabilistic theory. By using Terzaghi's consolidation theory as the objective function, the failure probability was normalized based on AFOSM method. As the result of reliability analysis, the occurrence probabilities for the cases of the target settlement of ${\pm}10%,\;{\pm}25%$ of the total settlement from the deterministic analysis were 30~50%, 60%~90%, respectively. Considering that the variation coefficients of input variable are almost similar as those of past researches, the acceptable error range of the total settlement would be expected in the range of 10% of the predicted total settlement. As the result of sensitivity analysis, the factors which affect significantly on the settlement analysis were the uncertainties of the compression coefficient Cc, the pre-consolidation stress Pc, and the prediction model employed. Accordingly, it is very important for the reliable prediction with high reliability to obtain reliable soil properties such as Cc and Pc by performing laboratory tests in which the in-situ stress and strain conditions are properly simulated.

• Geomechanics and Engineering
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• v.35 no.6
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• pp.603-615
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• 2023

Population growth and urbanization prompted engineers to propose more sophisticated and efficient transportation methods, such as underground transit systems. However, due to limited urban space, it is necessary to construct these tunnels in close proximity to existing infrastructure like high-rise buildings and bridges. Battered piles have been widely used for their higher stiffness and bearing capacity compared to vertical piles, making them effective in resisting lateral loads from winds, soil pressures, and impacts. Considerable prior research has been concerned with understanding the vertical pile response to tunnel excavation. However, the three-dimensional effects of tunnelling on adjacent battered piled foundations are still not investigated. This study investigates the response of a single battered pile to tunnelling at three critical depths along the pile: near the pile shaft (S), next to the pile (T), and below the pile toe (B). An advanced hypoplastic model capable of capturing small strain stiffness is used to simulate clay behaviour. The computed results reveal that settlement and load transfer mechanisms along the battered pile, resulting from tunnelling, depend significantly on the tunnel's location relative the length of the pile. The largest settlement of the battered pile occurs in the case of T. Conversely, the greatest pile head deflection is caused by tunnelling near the pile shaft. The battered pile experiences "dragload" due to negative skin friction mobilization resulting from tunnel excavation in the case of S. The battered pile is susceptible to induced bending moments when tunnelling occurs near the pile shaft S whereas the magnitude of induced bending moment is minimal in the case of B.

• Advances in nano research
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• v.17 no.2
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• pp.181-195
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• 2024

This study introduces a novel functionally graded material model, termed the "Coated Functionally Graded Graphene-Reinforced Composite (FG GRC)" model, for investigating the free vibration response of plates, highlighting its potential to advance the understanding and application of material property variations in structural engineering. Two types of coated FG GRC plates are examined: Hardcore and Softcore, and five distribution patterns are proposed, namely FG-A, FG-B, FG-C, FG-D, and FG-E. A modified displacement field is proposed based on the higher-order shear deformation theory, effectively reducing the number of variables from five to four while accurately accounting for shear deformation effects. To solve the equations of motion, an analytical solution based on the Galerkin approach was developed for FG GRC plates resting on a viscoelastic Winkler/Pasternak foundation, applicable to various boundary conditions. A comprehensive parametric analysis elucidates the impact of multiple factors on the fundamental frequencies. These factors encompass the types and distribution patterns of the coated FG GRC plates, gradient material distribution, porosities, nonlocal length scale parameter, gradient material scale parameter, nanoplate geometry, and variations in the elastic foundation. Our theoretical research aims to overcome the inherent challenges in modeling structures, providing a robust alternative to experimental analyses of the mechanical behavior of complex structures.