• Journal of Marine Life Science
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• v.6 no.1
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• pp.1-8
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• 2021

In marine ecosystems, the biosynthesis and catabolism of dimethylsulfoniopropionate (DMSP) by marine bacteria is critical to microbial survival and the ocean food chain. Furthermore, these processes also influence sulfur recycling and climate change. Recent studies using emerging genome sequencing data and extensive bioinformatics analysis have enabled us to identify new DMSP-related genes. Currently, seven bacterial DMSP lyases (DddD, DddP, DddY, DddK, DddL, DddQ and DddW), two acrylate degrading enzymes (DddA and DddC), and four demethylases (DmdA, DmdB, DmdC, and DmdD) have been identified and characterized in diverse marine bacteria. In this review, we focus on the biochemical properties of DMSP cleavage enzymes with special attention to DddD, DddA, and DddC pathways. These three enzymes function in the production of acetyl coenzyme A (CoA) and CO₂ from DMSP. DddD is a DMSP lyase that converts DMSP to 3-hydroxypropionate with the release of dimethylsulfide. 3-Hydroxypropionate is then converted to malonate semialdehyde by DddA, an alcohol dehydrogenase. Then, DddC transforms malonate semialdehyde to acetyl-CoA and CO₂ gas. DddC is a putative methylmalonate semialdehyde dehydrogenase that requires nicotinamide adenine dinucleotide and CoA cofactors. Here we review recent insights into the structural characteristics of these enzymes and the molecular events of DMSP degradation.

• Korean Journal of Clinical Pharmacy
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• v.17 no.1
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• pp.19-32
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• 2007

Objectives : It is necessary to monitor consumption of drugs in order to enhance promote appropriate use of drugs. Defined Daily Dose(DDD) of World Health Organization(WHO) has been used for evaluating the amount of medicine use. However, DDD of some drugs must be determined for drugs in Korea which are not listed by WHO. Our formulary follows ourself classification and DDD of some drugs must be determined since they exist only in Korea. This study was aimed to determine DDD value using RAND Appropriateness Methods and evaluate the amount of antibiotics use using DDD value. Methods : J01 antibiotics of WHO anatomical therapeutic chemical(ATC) classification were extracted from drug formulary. Antibiotics list without DDD was identified to determine their DDD with comprehensive review of references and recommendation of experts. defined. Review of reference was executed. of Expert panels were comprised of clinical pharmacist and clinical doctors. Modified Delphi Method was applied by survey and consensus meeting. Amount of antibiotic use was calculated by DDD/1000 inhabitants/day in the national level using health insurance claim data. Results : The result of 1 round, DDD values of 28 ingredients were determined from the first round of consensus meeting. With 2nd round meeting, 3 ingredients were deleted and DDD of 17 ingredients were decided. Analysis of antibiotic use in health insurance claim data showed 22.97 DDD/1000 inhabitants/day in 2003 year. Conclusion : This study can contribute to the establishment of DDD assignment and thus quantifying drug uses.

• Journal of Satellite, Information and Communications
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• v.11 no.4
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• pp.27-32
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• 2016

A conventional double diffused drain n-type MOSFET (DDD_NMOS) device shows SCR behaviors with very low snapback holding voltage and latch-up problem during normal operation. However, a modified DDD_NMOS-based silicon controlled rectifier (DDD_NSCR_CPS) device with a counter pocket source (CPS) structure is proven to increase the snapback holding voltage and on-resistance compare to standard DDD_NSCR device, realizing an excellent electrostatic discharge protection performance and the stable latch-up immunity.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1826-1835
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• 2019

Objective: Testicular growth and development are strongly influenced by androgen. Although both testis weight and plasma testosterone level are inherited traits, the interrelationship between them is not fully established. Males of DDD/Sgn (DDD) mice are known to have extremely heavy testes and very high plasma testosterone level among inbred mouse strains. We dissected the genetic basis of testis weight and analyzed the potential influence of plasma testosterone level in DDD mice. Methods: Quantitative trait loci (QTL) mapping of testis weight was performed with or without considering the influence of plasma testosterone level in reciprocal $F_2$ intercross populations between DDD and C57BL/6J (B6) mice, thereby assessing the influence of testosterone on the effect of testis weight QTL. Candidate genes for testis weight QTL were investigated by next-generation sequencing analysis. Results: Four significant QTL were identified on chromosomes 1, 8, 14, and 17. The DDDderived allele was associated with increased testis weight. The $F_2$ mice were then divided into two groups according to the plasma testosterone level ($F_2$ mice with relatively "low" and "high" testosterone levels), and QTL scans were again performed. Although QTL on chromosome 1 was shared in both $F_2$ mice, QTL on chromosomes 8 and 17 were identified specifically in $F_2$ mice with relatively high testosterone levels. By whole-exome sequencing analysis, we identified one DDD-specific missense mutation Pro29Ser in alpha tubulin acetyltransferase 1 (Atat1). Conclusion: Most of the testis weight QTL expressed stronger phenotypic effect when they were placed on circumstance with high testosterone level. High testosterone influenced the QTL by enhancing the effect of DDD-derived allele and diminishing the effects of B6-derived allele. Since Pro29Ser was not identified in other inbred mouse strains, and since Pro29 in Atat1 has been strongly conserved among mammalian species, Atat1 is a plausible candidate for testis weight QTL on chromosome 17.

• Environmental Analysis Health and Toxicology
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• v.19 no.2
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• pp.183-189
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• 2004

To obtain the residual organochlorine pesticides in the culture environment of ginseng on Sangju, Gyeongbuk, the analytical methods for BHC isomers, Aldrin, DDE, Dieldrin, DDD, Endrin and DDT by GCECD are surveyed. The relative retention times for $\alpha$-BHC, $\beta$-BHC, ${\gamma}$-BHC, $\delta$-BHC, Aldrin, DDE, Dieldrin, DDD, Endrin and DDT were 1.000, 1.042, 1.049, 1.086, 1.202, 1.335, 1.341, 1.371, 1.391 and 1.439, respectively The BHC isomers, Aldrin, DDE, Dieldrin, DDD, Endrin and DDT were separated on the base line. The qualified detection concentration for $\alpha$-BHC, $\beta$-BHC, ${\gamma}$-BHC and $\delta$-BHC is 0.43, 1.33, 0.54 and 1.63 ng/g and it's of Aldrin, DDE, Dieldrin, DDD, Endrin and DDT were 0.63, 0.50, 0.66, 0.74, 0.96 and 0.88ng/g, respectively. BHC isomers, Aldrin, DDE, Dieldrin, DDD, Endrin and DDT were not detected in culture environment of ginseng on Sanaju, Gyeongbuk. The detection concentration for Hg, Cd, Pb, Cr, and As in ginseng were 0.0086ppm, 0.0020ppm, 0.0200ppm, 0.0271ppm and 0.0220ppm, respectively, which were also lower than the 30ppm Korea Food & Drug Administration advisory level for heavy metal in herbal medicines.

• Korean Journal of Clinical Pharmacy
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• v.23 no.1
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• pp.26-32
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• 2013

Objective: This study was to define the clinical effect on the clinical decision support system (CDSS) for prescribing antibiotics integrated with the order communication system in a National Hospital. Method: We extracted data collected before integrating the CDSS of 4,406 adult patients in 2007 and data collected after integrating the CDSS of 4,278 adult patients in 2009. These patients were 50.4% and 45.2% of all patients admitted in 2007 and 2009, respectively. The clinical effect was defined as the proportion of prescribed antibiotics, the length of antibiotics use, and the DDDs (defined daily doses) of antibiotics per 1,000 patient-days using these retrospective data. Results: There were a significant change in the proportion of patient prescribed penicillins with extended spectrum (OR=0.55, p=001), penicillins included beta-lactamase inhibitors (OR=0.75, p<.001), 3rd cephalosporin (OR=1.47, p<.001). The mean of the length of antibiotics use was decreased statistically from $6.09{\pm}5.48$ to $5.85{\pm}5.51$ days (p=.003). The DDD of glycopeptides was decreased from 24.43 DDD to 19.55 DDD per 1000 patient-days. The DDD of 3rd cephalosporins was also decreased from 15.88 to 11.65. Conclusion: Therefore, the clinical decision support system for prescribing antibiotics was effective for the clinical outcomes.

• The Journal of the Acoustical Society of Korea
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• v.8 no.5
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• pp.102-112
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• 1989

In this paper, we proposed the study on speaker-independent isolated word recognition for DDD area-name using vector quantization and chose total 146 DDD area-name to recognize words for application of dialing system. We made the codebook using 12th LPC cepstrum coefficients and used the minsum and the minimax method to find the centroid and we applied 3 splitting rule to a codebook generation. The single section and the multi section with time information were used to generate the codebooks and the over-lapped section codebook was used, too. From the experiment result, we proved that the minsum method was better than the minimax method and the evaluation of the system yielded an accuracy of about 90 percents In case of speaker-independent.

• Journal of The Korean Association of Information Education
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• v.21 no.6
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• pp.619-627
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• 2017

The purpose of this study is to verify the effectiveness of the Development-oriented model (Discovery-Design-Development: DDD) for developing students' Computational Thinking skills in software education. DDD is a class model that learns the process of developing SW to solve real-life problems through three stages of Discovery, Design, and Development. In order to verify the effectiveness of the DDD, first grade students at G university who did not have SW education class were tested. As a result, the students who experienced SW development through DDD maintained the learning motivation of SW education before and after, especially the confidence area increased significantly. In addition, students also noted that the Design phase was particularly helpful in improving CT abilities and the DDD was a significant help in understanding of decomposition and algorithms.

• Korean Journal of Environmental Agriculture
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• v.3 no.2
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• pp.23-29
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• 1984

Agricultural soil samples collected from 121 sites (plastic film house 59, up-land 30 and orchard 32 sites) were evaluated by steam distillation and GLC-ECD analysis for organochlorine pesticides (${\gamma}-BHC$, heptachlor, p,p'-DDE, dieldrin, p,p'-DDD, and p,p'-DDT) in Jeollanam-Do area. Total residues of organochlorine pesticide in orchard, plastic film house and up-land were 0.415, 0.234 and 0.156ppm, respectively. Ninety-four percent of total residue was p,p'-DDT and its homologues (p,p'-DDE and p,p'-DDD). ${\gamma}-BHC$ was detected in all soil samples at $trace{\sim}0.050ppm$ range. Residue levels of organochlorine pesticide increased in the order of p,p'-DDE, ${\gamma}-BHC$, heptachlor, dieldrin, p,p'-DDT and p,p'-DDD.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.123-128
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• 2008

The MRLs (maximum residue limits) of DDT (DDD and DDE) in fresh ginseng, dried ginseng, and steamed red ginseng are set as low as 0.01 mg/kg, 0.05 mg/kg, and 0.05 mg/kg, respectively. Therefore, this study was undertaken to develop a simple and highly sensitive analysis method, as well as to reduce interfering ginseng matrix peaks, for the determination of DDT isomers (o,p'-DDE, p,p'-DDE, o,p'-DDD, p,p'-DDD, o,p'-DDT, and p,p'-DDT) in fresh ginseng, dried ginseng, and steamed red ginseng at the 0.01 mg/kg level. The method used acetonitrile extraction according to simultaneous analysis, followed by normal-phase Florisil solid-phase extraction column clean-up. The purification method entailed the following steps: (1) dissolve the concentrated sample extract in 7 mL hexane; (2) add 3 mL of $H_2SO_4$; (3) vigorously shake on avortex mixer; (4) cetrifuge at 2000 rpm for 5 min; (5) transfer 3.5 mL of the supernatant to the Florisil-SPE (500 mg/6 mL);and (6) elute the SPE column with 1.5 mL of hexane and 10 mL of ether/hexane (6:94). The determination of DDT isomers was carried out by a gas chromatography-electron capture detector (GC-${\mu}$ECD). The hexane and ether/hexane (6:94) eluate significantly removed chromatographic interferences, and the addition of 30% $H_2SO_4$ to the acetonitrile extract effectively reduced many interfering ginseng matrix peaks, to allow for the determination of the DDT isomers at the 0.01 mg/kg level. The recoveries of the 6 fortified (most at 0.01 mg/kg) DDT isomers from fresh ginseng, dried ginseng, and steamed red ginseng ranged from 87.9 to 99.6%. The MDLs (method detection limits) ranged from 0.003 to 0.009 mg/kg. Finally, the application of this method for the determination of DDT isomers is sensitive, rapid, simple, and inexpensive.