• Ecology and Resilient Infrastructure
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• v.4 no.3
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• pp.180-185
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• 2017

Restoration of min-impacted arable land is often performed through stabilization of trace elements by amendment treatment combined with (clean) soil covering on the surface. Recently, soil loss problem from sloping remediated agricultural lands has risen as an emerging concern. In this study, efficacy of aggregation formation was assessed by single and binary treatments of four potential amendments (bentonite, lime, organic matter, and steel slag) applied on three cover soils having different clay contents (9.4, 14.7, and 21.2% for A, B, and C soils respectively). In results of single treatments, 5% organic matter for A soil and 5% lime for B and C soils were found most effective for the aggregation formation compared to the respective controls (without amendments). Among nine binary treatments, 3% organic matter + 1% lime for A soil and 1% organic matter + 3% lime for both B and C soils led to the highest formation of aggregation (30.4, 25.0, and 36.5% for A, B, and C soils). For a site-application, the soil erodibility difference between the cover soils (0.045, 0.051, and 0.054 for A, B, and C soils, respectively) and the national average of arable land (0.032) was assumed to be compensated by amendment addition, which is equivalent to 29.1% aggregation formation. To achieve the aggregation goal, 5% lime for A and B soils and 3% lime for C soil were best in the consideration of benefit/cost, thereby effectively and economically reducing soil loss from sloping remediation site. Soil alkalinity induced by lime treatment was not considered in this work.

• Journal of Digital Convergence
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• v.15 no.2
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• pp.335-345
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• 2017

It is necessary for an instructor to understand the student's team building behavior for an effective guidance of team activities. In this study, we developed an agent-based computational model for simulating the student's self-controlled behavior. We validated the model by comparing the actual behavior. Through the simulation, we found that the time to stabilization of team formation and the ratio of the students having no team are decreasing as the population of the student increases. However, we also found that over a certain amount of population, the time and the ratio do not show much progress in the difference. The simulation also shows that the more heterogeneity between the students the higher chance of delaying the team formation and increasing the ratio. We expect to use the model as a tool for guiding and supporting students' team activities.

• Environmental Engineering Research
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• v.19 no.3
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• pp.241-245
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• 2014

The As accumulation in part of roots, shoots, husks and grains of rice plants was significantly decreased with the increasing dosage of kaolin addition from 0.5% to 10% w/w. Kaolin addition could reduce As accumulation in rice plants, which mainly could be attributed to the formation of stable crystalline Al oxides bound As that decreased the available As in soil with decreased As accumulation in rice plants. The pH values of the soils did not change significantly when amended with kaolin. The pH values of the soils was neural that proper to adsorb of arsenic with $Al_2O_3$. Arsenic tends to adsorb with $Al_2O_3$ at acid neutral pH and with desorbing at alkaline pH. The dry weight of rice plant was significantly increased with the increasing dosage of kaolin addition from 2.5% to 10% w/w. The highest dry weight of rice plants was 6.67 g/pot achieved at kaolin addition of 10% w/w with about 13% increasing over the control, which was probably attributed to the highest As concentration formation with kaolin at this dosage. The results of this study indicated that kaolin has the potential to reduce As accumulation in rice plants and enhance the dry weight of rice plants.

• Korean Journal of Microbiology
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• v.27 no.4
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• pp.357-365
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• 1989

Induction conditions for autolysis and autoplast formation of thermophilic Clostridium thermohydrosulfuricum were studied. The cells in the initial exponential growth phase were well autolysed in Tris-HCl buffer or inorganic buffers containing univalents, such as $K^{+}$ and $Na^{+}$ , and chemicals such as cysteine-HCl, sorbitol and glycerol. Meanwhile, autolysis induction was slightly inhibited by divalents, such as $Mg^{2+}, Mn^{2+}, Ca^{2+}, Ni^{2+}$, and strongly by divalents, such as $Fe^{2+}, Cu^{2+}$ and citric acid. The autolysis was stimulated when the cells were grown in the medium containing ampicillin that inhibites cell wall synthesis, meanwhile, it was slightly inhibited by nucleic acids and protein synthesis inhibitors. The optimal pH and temperature for the induction of autolysis were 7.5 and $60^{\circ}C$, respectively. On the other hand, the cells were autoplasted without lysozyme treatment during autolysis due to the stabilization of protoplasmic membrane in the presence of divalents such as $Mg^{2+}, Mn^{2+}, Ca^{2+}, Ni^{2+}$. Autoplast formation was mostly induced at $37^{\circ}C$ in 50mM Tris-HCl buffer (pH 7.5) containing 20 mM $MgCl^{2}$ and 0.3 M glycerol, and in the late exponential growth phase growing cell.

• Membrane and Water Treatment
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• v.10 no.3
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• pp.213-221
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• 2019

Anaerobic digestion (AD) has been widely used to valorize food waste (FW) because of its ability to convert organic carbon into $CH_4$ and $CO_2$. Korean FW has a high content of fruits and vegetables, and efficient hydrolysis of less biodegradable fibers is critical for its complete stabilization by AD. This study examined the digestates from different anaerobic digesters, namely Rs, Rr, and Rm, as the inocula for the AD of vegetable waste (VW) and cellulose (CL): Rs inoculated with anaerobic sludge from an AD plant, Rr inoculated with rumen fluid, and Rm inoculated with anaerobic sludge and augmented with rumen fluid. A total of six conditions ($3\;inocula{\times}2\;substrates$) were tested in serial subcultures. Biogas yield was higher in the runs inoculated with Rm than in the other runs for both VW (up to 1.10 L/g VS added) and CL (up to 1.05 L/g VS added), and so was biogas production rate. The inocula had different microbial community structures, and both substrate type and inoculum source had a significant effect on the formation and development of microbial community structures in the subcultures. The overall results suggest that the bioaugmentation with rumen microbial consortium has good potential to enhance the anaerobic biodegradability of VW, and thereby can help more efficiently digest high fiber-content Korean FW.

• Journal of Family Resource Management and Policy Review
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• v.11 no.4
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• pp.73-92
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• 2007

This study explored the integration-support paradigm for transnational marriages and families as a well-grounded service model supporting a transnational family of immigrants in Korea at a time when Korean society showed increased interest in interracial marriages. The research mainly focused on the Dongdaemun-gu Transnational Marriage and Family Support Center, utilizing the relative actual practice at the center and the secondary data of previous studies. The findings were as follows: The integration-support paradigm for transnational marriage and family comprised of the following elements : the institutionalization of welfare and medical services; the systematization of legal institution and execution the settlement of mid- and long-term policies and the practical programs of the government proper approaches to the formation of a healthy marital couple and family relations; total services related to rearing and educating children properly including education cost support to family incomehousing for the stabilization of family life support for socio-cultural exchanges within the family : as well as the radical conversion of social recognition of a transnational family. This paradigm is expected to be a well-grounded service for the integration-support of transnational families.

• Membrane and Water Treatment
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• v.8 no.6
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• pp.517-528
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• 2017

This study evaluates the performance of membrane bioreactor (MBR) coupled with a modified walnut shell granular activated carbon (WSGAC) for tannery wastewater treatment. For this purpose, a pilot with overall volume of 80L and 12 hours hydraulic retention time (HRT) is operated in three scenarios. Here, the chemical oxidation demand (COD) of wastewater is reduced more than 98% in both C:N ratios of 13 (S1) and 6.5 (S2). This performance also remains intact when alkalinity depletes and pH reduces below 6 (S3). The ammonium removal ranges between 99% (S2) and 70% (S3). The reliability of system in different operating conditions is due to high solids retention time and larger flocs formation in MBR. The average breakthrough periods of WSGAC are determined between 15 minutes (S2) and 25 minutes (S1). In this period, the overall nitrate removal of MBR-WSGAC exceeds 95%. It is also realized that adding no chemicals for alkalinity stabilization and consequently pH reduction of MBR effluent (S3) can slightly lengthen the breakthrough from 15 to 20 minutes. Consequently, MBR can successfully remove the organic content of tannery wastewater even in adverse operational conditions and provide proper influent for WSGAC.

• Applied Microscopy
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• v.45 no.3
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• pp.107-114
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• 2015

Two-dimensional (2D) materials containing hole defects are a promising substitute for conventional nanopore membranes like silicon nitride. Hole defects on 2D materials, as atomically thin nanopores, have been used in nanopore devices, such as DNA sensor, gas sensor and purifier at lab-scale. For practical applications of 2D materials to nanopore devices, researches on characteristics of hole defects on graphene, hexagonal boron nitride and molybdenum disulfide have been conducted precisely using transmission electron microscope. Here, we summarized formation, features, structural preference and stability of hole defects on 2D materials with atomic-resolution transmission electron microscope images and theoretical calculations, emphasizing the future challenges in controlling the edge structures and stabilization of hole defects. Exploring the properties at the local structure of hole defects through in situ experiments is also the important issue for the fabrication of realistic 2D nanopore devices.

• BMB Reports
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• v.52 no.2
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• pp.119-126
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• 2019

The tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) initiates the extrinsic apoptotic pathway through formation of the death-inducing signaling complex (DISC), followed by activation of effector caspases. TRAIL receptors are composed of death receptors (DR4 and DR5), decoy receptors (DcR1 and DcR2), and osteoprotegerin. Among them, only DRs activate apoptotic signaling by TRAIL. Since the levels of DR expressions are higher in cancer cells than in normal cells, TRAIL selectively activates apoptotic signaling pathway in cancer cells. However, multiple mechanisms, including down-regulation of DR expression and pro-apoptotic proteins, and up-regulation of anti-apoptotic proteins, make cancer cells TRAIL-resistant. Therefore, many researchers have investigated strategies to overcome TRAIL resistance. In this review, we focus on protein regulation in relation to extrinsic apoptotic signaling pathways via ubiquitination. The ubiquitin proteasome system (UPS) is an important process in control of protein degradation and stabilization, and regulates proliferation and apoptosis in cancer cells. The level of ubiquitination of proteins is determined by the balance of E3 ubiquitin ligases and deubiquitinases (DUBs), which determine protein stability. Regulation of the UPS may be an attractive target for enhancement of TRAIL-induced apoptosis. Our review provides insight to increasing sensitivity to TRAIL-mediated apoptosis through control of post-translational protein expression.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.3
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• pp.262-267
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• 2006

The term temporomandibular disorders is used to describe a group of conditions that involve the temporomandibular joint, masticatory muscles, and associated structures. Many modalities have been proposed for treating temporomandibular disorders, including medication, physical therapy, occlusal stabilization splints with or without manual repositioning, surgery, and arthrocentesis. Temporomandibular disorders are treated in a step-wise manner. Initially, conservative treatment is used. Depending on the response, more aggressive interventions may be necessary. This usually takes the form of arthrocentesis. Arthrocentesis is used in the treatment of not only acute, closed, and locked TMJs but also various other temporomandibular disorders. Recently, the intra-articular injection of sodium hyaluronate after arthrocentesis was shown to have long-term palliative effects on TMJ symptoms. Synovial fluid consists of plasma and glycosaminoglycan, including hyaluronic acid derived from synovial cells. Sodium hyaluronate, the sodium salt of hyaluronic acid, is a high-molecular-weight polysaccharide and a major component of synovial fluid. This highly viscous substance has analgesic properties, lubricant effects, and anti-inflammatory actions; it causes cartilage formation and plays a role in the nutrition of avascular parts of the disc and condylar cartilage. We conclude that the intra-articular injection of sodium hyaluronate is effective for treating temporomandibular disorders.