• Molecules and Cells
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• v.22 no.3
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• pp.353-359
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• 2006

The bone morphogenetic protein (BMP) family has been implicated in control of cartilage development. Here, we demonstrate that BMP-2 promotes chondrogenesis by activating p38 mitogen-activated protein kinase (MAPK), which in turn downregulates $Wnt-7a/{\beta}$-catenin signaling responsible for proteasomal degradation of Sox9. Exposure of mesenchymal cells to BMP-2 resulted in upregulation of Sox9 protein and a concomitant decrease in the level of ${\beta}$-catenin protein and Wnt-7a signaling. In agreement with this, the interaction of Sox9 with ${\beta}$-catenin was inhibited in the presence of BMP-2. Inhibition of the p38 MAPK pathway using a dominant negative mutant led to sustained Wnt-7a signaling and decreased Sox9 expression, with consequent inhibition of precartilage condensation and chondrogenic differentiation. Moreover, overexpression of ${\beta}$-catenin caused degradation of Sox9 via the ubiquitin/26S proteasome pathway. Our results collectively indicate that the increase in Sox9 protein resulting from downregulation of ${\beta}$-catenin/Wnt-7a signaling is mediated by p38 MAPK during BMP-2 induced chondrogenesis in chick wing bud mesenchymal cells.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.3
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• pp.14-25
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• 2019

From 2019 onwards, more stringent regulations (from Stage 4 to Stage 5) are to be implemented in Europe in order to reduce the air pollutant emissions. In South Korea, the government authorities started to make new regulation to meet the European regulation. As a first step, the air pollutant emissions such as CO, NOx, SOx, TSP, $PM_{10}$, $PM_{2.5}$, VOC, $NH_3$ by agricultural machinery were analyzed based on CAPSS inventory along with the analysis in the general aspect in this study. Three levels of analysis was conducted each in agricultural machinery aspect along with in the general aspect. Per agricultural tractor, all kinds of the air pollutant emissions decreased by 25, 25, 99, 25, 25, 25, 25% for the CO, NOx, SOx, TSP, $PM_{10}$, VOC, $NH_3$ emissions each from the year 2000 to the year 2014. Per combine harvester, all kinds of the air pollutant emissions decreased by 63, 63, 91, 63, 63, 63, 63% for the CO, NOx, SOx, TSP, $PM_{10}$, VOC, $NH_3$ emissions each from the year 2000 to the year 2014.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.59.3-60
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• 2000

No Abstract, See Full Text

• Journal of Microbiology
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• v.41 no.2
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• pp.109-114
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• 2003

A promoter that is inducible by paraquat and menadione, the superoxide generators, independently of soxRS has been found in front of the sufABCDSE operon in Escherichia coli. Based on the observation that SufA is a holomog of IscA that functions in the assembly of iron sulfur cluster and the sufA promoter (sufAp) contains a putative Fur-binding consensus, we investigated whether this gene is regulated by Fur, a ferric uptake regulator, When examined in several sufAp-lacZ chromosomal fusion strains, sufAp was induced by EDTA, an iron chelator and a well-known Fur-inducer, The basal level of sufA expression increased dramatically in fur mutant, suggesting repression of sufAp by Fur. The derepression in fur mutant and EDTA-induction of sufA expression required nucleotides up to -61, where a putative Fur box is located. Purified Fur protein bound to the DNA fragment containing the putative Fur box between -35 and -10 promoter elements. The regulation by Fur and menadione induction of sufAp acted independently. The rpoS mutation increased sufA induction by menadione, suggesting that the stationary sigma factor RpoS acts negatively on sufA induction.

• Journal of Environmental Policy
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• v.12 no.2
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• pp.59-86
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• 2013

We analyzed the correlation among the GHG (Greenhouse Gas) emission, energy consumption and economic growth for the 6 specific regions in Korea by using Panel approaches with the test of the EKC hypothesis. We also analyzed the effects of environmental regulation on GHG and economic growth. The results show that by testing of the EKC (Environmental Kuznets Curve) hypothesis model,the effects of the environmental regulation and the structure of industries on GHC emission have a significant result on the regional analysis for SOx. For the NOx and TSP, only TK region passed the turning point of the EKC among the 6 specific regions. And, for the Co, the Central, Honam and the PUKN region passed the turning point of the EKC. This is because GHG emissions by the environment regulation had a weak path effect and also regional industry structures had a weak relation with regional GHG emissions.

• Journal of Korea Port Economic Association
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• v.34 no.4
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• pp.141-160
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• 2018

In this paper, to analyze the perception and response strategy of Korean ship owners on Global Sulphur Cap 2020, examined the IMO environmental regulation status focusing on MARPOL Annex VI regulation about air pollution prevention, technological measures to reduce SOx emission, shipping industry and management status of Korean ship owners. First of all, the questionnaire was conducted for Korean ship owners after selecting the evaluation factors. The purpose of this study was to investigate the difference of the perception and response strategy of Korean ship owners by corporation size and main vessel type using frequency and cross analysis. It is confirmed that various researches on SOx emission reduction have been carried out from various points of view at home and abroad. In this study, existing studies related to technical factors for regulatory response and economics analysis were examined and evaluation factors were selected. As a result of analysis, it is found that large-sized shipping companies are more prepared for regulatory response than small and medium-sized bulk carrier owners. There were similar perception and the direction of response strategy about the impacts by corporation size and main vessel type. In about two years to be implemented in 2020, It is necessary to find an appropriate response strategy based on the support policy of the government and related organizations and the systematic analysis of the ship owners. Through this study, although the difference between the perception and response strategy of the ship owners by corporation size and main vessel type was understood, it was found that there were limitations on specific response strategy and corporate data collection. In future research, we should overcome the limitations of this study and conduct an in-depth study.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.609-612
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• 2007

The co-combustion of coal and RPF(Refuse Plastic Fuel) mixture has been experimented in a commercially operating CFB coal boiler and the emissions such as SOx, NOx, TSP and dioxine were measured at the stack. The experimented RPF was supplied by domestic RPF company that is commercially producing RPF pellet from the wasted plastics. Up to 15% of total coal was substituted to RPF and no trouble was happened during normal boiler operation. SOx and NOx concentration was reduced about $15{\sim}20$% and TSP(Total Suspended Particle) was drastically reduced about 30% during co-combustion. Dioxine concentration at mixing ratio of 7.5% was $0.0487ng{\sim}TEQ/Sm^3$ ($O_2$, 12%) that satisfied governmental emission regulation.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.208-208
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• 2017

• Journal of Navigation and Port Research
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• v.43 no.2
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• pp.86-92
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• 2019

IMO has enacted a convention that air pollution due to emissions of ships and sulfur oxides emissions should be significantly reduced by 2020. Based on the current support policies, this work intended to draw up the government support plans required by the shipping companies. Analytic Hierarchy Process analysis was done with factors derived from brainstorming and literature studies. The analysis results showed that the cost factor was generally the most important criterion and the Financial Aid was relatively more important within this cost factor. The policy implications for the regulation of sulfur oxides emissions was provided.

• Journal of Life Science
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• v.21 no.4
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• pp.534-541
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• 2011

Retinoic acid (RA), a metabolite of vitamin A, is known to regulate dedifferentiation of rabbit articular chondrocytes. The regulatory mechanism of dedifferentiation by RA is not yet understood. Thus, the effect of RA on the regulation of nitric oxide (NO)-induced dedifferentiation was investigated in rabbit articular chondrocytes. RA caused loss of the differentiated chondrocyte phenotype as demonstrated by inhibition of type II collagen expression and proteoglycan synthesis. RA also accelerated NO-induced dedifferentiation in rabbit articular chondrocytes as detected by expression of type II collagen and Sox-9 using Western blot analysis and production of sulfated proteoglycan using Alcain blue staining. Further, RA potentiated NO-induced activation of ERK. Inhibition of ERK with PD98059 (PD) recovered the expression of type II collagen and Sox-9 and production of sulfate proteoglycan in NO-induced dedifferentiated chondrocytes by RA treatment. Our findings suggest that RA accelerates NO-induced dedifferentiation of rabbit articular chondrocytes via the ERK pathway.