• Journal of Microbiology and Biotechnology
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• v.27 no.2
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• pp.306-315
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• 2017

Metabolic engineering with a high-yielding mutant, A. terreus AN37, was performed to enhance the production of itaconic acid (IA). Reportedly, the gene cluster for IA biosynthesis is composed of four genes: reg (regulator), mtt (mitochondrial transporter), cad (cis-aconitate decarboxylase), and mfs (membrane transporter). By overexpressing each gene of the IA gene cluster in A. terreus AN37 transformed by the restriction enzyme-mediated integration method, several transformants showing high productivity of IA were successfully obtained. One of the AN37/cad transformants could produce a very high amount of IA (75 g/l) in shake-flask cultivations, showing an average of 5% higher IA titer compared with the high-yielding control strain. Notably, in the case of the mfs transformants, a maximal increase of 18.3% in IA production was observed relative to the control strain under the identical fermentation conditions. Meanwhile, the overexpression of reg and mtt genes showed no significant improvements in IA production. In summary, the overexpressed cis-aconitate decarboxylase (CAD) and putative membrane transporter (MFS) appeared to have positive influences on the enhanced IA productivity of the respective transformant. The maximal increases of 13.6~18.3% in IA productivity of the transformed strains should be noted, since the parallel mother strain used in this study is indeed a very high-performance mutant that has been obtained through intensive rational screening programs in our laboratory.

• Korean Journal of Organic Agriculture
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• v.20 no.3
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• pp.297-311
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• 2012

Since 1997, Korean Ministry of Knowledge Economy and Ministry of Environment have established data on some 400 basic raw and subsidiary materials and process like energy, petro-chemical, steel, cement, glass, paper, construction materials, transportation, recycling and disposal etc by initiating establishment of LCI database. Regarding agriculture, Rural Development Administration has conducted establishment of LCI database for major farm products like rice, barley, beans, cabbage and radish etc from 2009, and released that they would establish LCI database for 50 items until 2020 later on. The domestic LCI database for seeds, seedling, agrochemical, inorganic fertilizer and organic fertilizer etc is only at initial stage of establishment, so overseas LCI databases are brought and being used. However, since the domestic and overseas natural environments differ, they fall behind in reliability. Therefore, this study has the purpose to select organic farming materials, survey the production process for various types of organic farming materials and establish LCI database for the effects of greenhouse gas emitted during the process in order to select carbon basic units for agricultural production system compliant in domestic situation instead of relying on overseas data and apply life cycle assessment of greenhouse gas emitted by each crop during the process. As for selecting methods, in this study organic farming materials were selected in the method of direct observation of material and bottom-up method a survey method with focus on the organic farming materials admitted into rice production. For the basic unit of carbon emission amount by the production of 1kg of organic farming material, the software PASS 4.1.1 developed by Korea Accreditation Board under Ministry of Knowledge Economy was used. The study had the goal to ultimately provide basic unit to calculate carbon emission amount in executing many institutions like goal management system and carbon performance display system etc in agricultural sector to be conducted later on. As a result, emission basic units per 1kg of production were calculated to be 0.0088kg-$CO_2$ for charcoal, 0.1319kg-$CO_2$ for grass liquid, and 0.2804kg-$CO_2$ for microbial agent.

• Korean Journal of Construction Engineering and Management
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• v.23 no.6
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• pp.89-100
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• 2022

The development of the Construction Production Rates System for appropriate construction cost calculation has recently come to the fore as a means of invigorating OSC based PC structure which currently needs institutional frameworks. PC structure based construction expenses consist of the factory-built assembly, transportation and on-site installation. Recently, in the field of transportation and site installation, research on product structure development is being conducted, such as presenting the standard product calculation system reflecting the results of field survey for each subsidiary materials (Lee et al., 2021). On the other hand, there is no ongoing research on estimating construction expenses of Factory-built assembly. This study suggests Construction Production Rates System which can be used for PC subsidiary materials based Factory-built assembly cost estimations. For the research, work types for the construction procedures have been categorized, and the standard input manpower suitable for the corresponding work characteristics has been derived from analyzing the associated Construction Standard Production Rates for each work type. Also, as the research referred PC subsidiary materials (such as columns, beams, walls, and slab, as well as on-site installation) and the standard number of workforce based on work types, one can calculate direct labor cost, using what the research shows. In addition, it suggests that the size of individual subsidiary materials be the extra cost factor, by using the characteristics that productivity changes depending on the size(m³) of subsidiary materials. It is expected that the research can contribute to objectively verifying factory-built assembly cost through of PC structure, which currently relies on estimates.

• Research in Community and Public Health Nursing
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• v.10 no.2
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• pp.508-524
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• 1999

We would like to identify the current status and the problem of the material for sexual education in Korea by analyzing the contents and the subjects of the materials. The 274 materials were collected from 80 institutes from March 1999 to June 1999. The collected ones were analyzed according to title. year of production. producer. subjects of materials and contents. Also, the materials in the internet was searched. Result were summarized by the descriptive statistics with SPSS/PC as followings: Type of materials were video tape (155), books (70), projection slides (43) and CD-ROM (6); Number of production from each institute were 54 from Planned Parenthood Federation of Korea, 39 from Korea Broadcasting System. 23 from Seoul School Health Center. 22 from Seoul Education and Science Research Institute, 16 from Korea Sexual Violence Relief Center, 13 from Republic of Korean National Redcross. and 10 from Korea Educational Development Institute; Subjects of the materials were middle and high school children (55), teachers (35), primary schoolchildren (17) and adult (14), preschool children (5). One hundred forty eight materials did not indicate the specific subjects; Thirty institutes had been providing the information for sexual education and the counseling. According to the above results. we suggest the followings: The systematic development of materials for sexual education appropriate to the specific subjects should be done: Materials in the CD-ROM and internet homepage should be developed more and more; The evaluation tool should be developed and adapted to the materials for the recommendation of the good materials; Database of the sexual materials should be provided for further development, evaluation and utilization.

• Journal of the Korean institute of surface engineering
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• v.55 no.3
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• pp.180-186
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• 2022

The production of hydrogen via water electrolysis (i.e., green hydrogen) using renewable energy is key to the development of a sustainable society. However, most current electrocatalysts are based on expensive precious metals and require the use of highly purified water in the electrolyte. We demonstrated the preparation of a non-precious metal catalyst based on CuCo₂O₄ (CCO) via simple electrodeposition. Further, an optimization process for electrodeposition potential, solution concentration and electrodeposition method was develop for a catalyst-substrate integrated electrode, which indicated the highly electrocatalytic performance of the material in electrochemical tests and when applied to an anion exchange membrane water electrolyzer.

• Journal of the Korean Ceramic Society
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• v.55 no.3
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• pp.224-229
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• 2018

OPC production requires high calorific value and emits a large amount of $CO_2$ through decarbonation of limestone, accounting for about 7% of $CO_2$ emissions. To reduce $CO_2$ emissions during the Ordinary Portland Cement (OPC) production process, there is a method of reducing the consumption of cement or lower temperature calcination for OPC product. In this study, for energy consumption reduction, we prepared Hauyne-belite cement by calcination at a low temperature compared to that used for OPC and studied the early hydration properties of the synthesized Hauyne-belite cement. We set the ratios of Hauyne and belite to 8 : 2, 5 : 5 and 3 : 7. For the hydration properties of the synthesized Hauyne-belite cement, we tested heat of hydration of paste and the compressive strength of mortar, using XRD and SEM for analysis of hydrates. As for our results, the temperature for optimum synthesis of Hauyne-belite is $1,250^{\circ}C$. Compressive strength of synthesized Hauyne-belite cement is lower than that of OPC, but it is confirmed that compressive strength of synthesized Hauyne-belite cement with mixing in of some other materials can be similar to that of OPC.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.190.1-190.1
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• 2015

Graphite has excellent mechanical and physical properties. It is known to advanced materials and is used to materials for molds, thermal treatment of furnace, sinter of diamond and cemented carbide tool etc. SiC materials are coated on the surface and holes of graphite to protect particles emitted from porous graphite with 5%~20% porosity and make graphite hard surface. SiC materials have high durability and thermal stability. Thermal CVD method is widely used to manufacture SiC thin films but high cost of machine investment and production are required. SiC thin films manufactured by Si reaction liquid and vapore with carbon are effective because of low cost of machine and production. SiC thin films made by vapor silicon infiltration into porous graphite can be obtained for shorter time than liquid silicon. Si materials are evaporated to the graphite surface in about $10^{-2}$ torr and high temperature. Si materials are melted in $1410^{\circ}C$. Si vapor is infiltrated into the surface hole of porous graphite and $Si_xC_y$ compound is made. $Si_x$ component is proportional to the Si vapor concentration. Si diffusion coefficient is estimated from quadratic equation obtained by Fick's second law. The steady stae is assumed. Si concentration variation for the depth from graphite surface is fitted to quadratic equation. Diffusion coefficient of Si vapor is estimated at about $10^{-8}cm^2s^{-1}$.

• Korean Journal of Materials Research
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• v.14 no.12
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• pp.857-862
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• 2004

Production of titanium powder directly from tantalum oxides ($TiO_2$) pellet through an electronically mediated reaction (EMR) by calciothermic reduction has been investigated. Feed material ($TiO_2\;pellet$) and reductant (Ca-Ni alloy) were charged into electronically isolated locations in a molten calcium chloride ($CaCl_2$) bath at $950^{\circ}C$. The current flow through an external circuit between the feed (cathode) and reductant (anode) locations was monitored during the reduction of $TiO_2$. The current approximately 3.2A was measured during the reaction in the external circuit connecting cathode and anode location. After the reduction experiment, pure titanium powder with low nickel content was obtained even though Ca-Ni alloy was used as a reductant. These results demonstrate that titanium powder can be produced without direct physical contact between the feed and reductant. In certain experimental conditions, pure titanium powder with approximately $99.5\;mass\%$ purity was successfully obtained.

• Korean Journal of Pharmacognosy
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• v.52 no.2
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• pp.92-98
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• 2021

Gryllus bimaculatus extract (GbE) have reported that anti-inflammatory activity by suppression of pro-inflammatory cytokines. However, the effects of fermented Gryllus bimaculatus extract (FGbE) have not yet been investigated. In this study, we evaluated the anti-inflammatory and anti-wrinkle effect of the fermented Gryllus bimaculatus extracts using Bacillus subtilis (JB PMB-18) in RAW264.7 cells. Both GbE and FGbE exerted no cytotoxic effects until 1000 ㎍/mL concentration. FGbE decreased NO production and decreased iNOS and COX-2 mRNA levels in a concentration-dependent manner. In addition, the protein production of inflammatory cytokines TNF-α, IL-1β and IL-6 was effectively reduced compared to the GbE. Inhibitory activities of elastase and collagenase associated with skin wrinkle improvement were measured to be 45% and 69%, respectively, at a concentration of 500 ㎍/mL in FGbE. From these results, FGbE can be used as a health functional food and skin functional cosmetic materials for preventing inflammatory diseases because it has excellent anti-inflammatory and anti-wrinkle effects.

• Restorative Dentistry and Endodontics
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• v.48 no.1
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• pp.6.1-6.14
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• 2023

Objectives: This study evaluated the effects of high-plasticity mineral trioxide aggregate (MTA-HP) on the activity of M1 and M2 macrophages, compared to white MTA (Angelus). Materials and Methods: Peritoneal inflammatory M1 (from C57BL/6 mice) and M2 (from BALB/c mice) macrophages were cultured in the presence of the tested materials. Cell viability (MTT and trypan blue assays), adhesion, phagocytosis, reactive oxygen species (ROS) production, and tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-β production were evaluated. Parametric analysis of variance and the non-parametric Kruskal-Wallis test were used. Results were considered significant when p < 0.05. Results: The MTT assay revealed a significant decrease in M1 metabolism with MTA-HP at 24 hours, and with MTA and MTA-HP later. The trypan blue assay showed significantly fewer live M1 at 48 hours and live M2 at 48 and 72 hours with MTA-HP, compared to MTA. M1 and M2 adherence and phagocytosis showed no significant differences compared to control for both materials. Zymosan A stimulated ROS production by macrophages. In the absence of interferon-γ, TNF-α production by M1 did not significantly differ between groups. For M2, both materials showed higher TNF-α production in the presence of the stimulus, but without significant between-group differences. Likewise, TGF-β production by M1 and M2 macrophages was not significantly different between the groups. Conclusions: M1 and M2 macrophages presented different viability in response to MTA and MTA-HP at different time points. Introducing a plasticizer into the MTA vehicle did not interfere with the activity of M1 and M2 macrophages.