• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1623-1624
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• 2006

It is a paper for design, manufacture and estimation of industry inkjet head. Simulations for Actuator, Ink flow and Ejection are executed for securing design ability. Relations between droplet and properties of ink are explained closely through simulation for nozzle. Actually, two silicon plates are made by dry and wet etching and directly bonded. PZT materials is attached on the bended ink flow part and cut to $540{\mu}m$ interval by dicing saw. Actuator was seen variation within 10% between simulation and actual head. Through the ejection estimation, it is shown that stabilized driving voltages change according to viscosity and surface tension of metal ink. Using the metal ink of viscosity of 4.8 cps and surface tension of 0.025 N/m, it is possible to eject the stable droplets with 5m/s, 20 pl, 5 kHz.

• Research in Plant Disease
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• v.16 no.2
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• pp.136-140
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• 2010

Pectobacterium carotovorum subsp. carotovorum causes soft rot disease in diverse plants. Carocin D is bacteriocin that is produced by Pectobacterium carotovorum subsp. carotovorum Pcc21 strain. Nonpathogenic mutant P. carotovorum subsp. carotovorum Pcc21-M15 strain was obtained by mutagenesis with Tn5 insertion and screened pathogenesity. P. carotovorum subsp. carotovorum Pcc21-M15 and E. coli (pRG3431), carocin D gene-transformed E. coli, produce carocin D against P. carotovorum subsp. carotovorum Pcc3. Pathogenic P. carotovorum subsp. carotovorum Pcc3 and mixture with Pcc21-M15 or E. coli (pRG3431) were treated with lettuces. Pcc21-M15 and E. coli (pRG3431) effectively suppressed the development of soft-rot disease. While symptoms in 90% of Pcc3-treated lettuces were observed after 3 days, only 25% of Pcc3 and Pcc21-M15-treated lettuces were observed to be infected after 6 days. These results suggest that the nonpathogenic strain P. carotovorum subsp. carotovorum. Pcc21-M15 and E. coli (pRG3431) are effective to soft-rot disease suppression.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.5
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• pp.261-267
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• 2002

The aim of the present study was to investigate the interaction of $estradiol-17{\beta}-bovine$ serum albumin $(E_2-BSA)$ and calcitropic hormones, such as parathyroid hormone, calcitonin, and vitamin D, in regulation of $Ca^{2+}$ uptake in primary cultured renal proximal tubule cells. Statistically significant increase in $Ca^{2+}$ uptake was found from 2 hours after $(E_2-BSA)\;(10^{-9}\;M)$ treatment, while $estradiol-17{\beta}\;(10^{-9}\;M)$ did not affect. Treatment of the cells with $(E_2-BSA)\;(10^{-9}\;M)$ together with parathyroid hormone (PTH) $(10^{-8}\;M),$ vitamin D $(10^{-8}\;M),$ or calcitonin $(10^{-8}\;M)$ significantly stimulated $Ca^{2+}$ uptake by 32.50%, 29.30%, or 27.75%, respectively, compared with the control. However, calcitropic hormones did not exhibit any synergistic effect on the E2-BSA-induced stimulation. $E_2-BSA$ significantly increased cAMP generation and PKC activity. The stimulatory effect of cotreatment of $E_2-BSA$ and PTH or vitamin D was blocked by SQ22536 (an adenylate cyclase inhibitor) and staurosporine (a PKC inhibitor), but the effect of cotreatment of $E_2-BSA$ and calcitonin was not blocked. Furthermore, 8-Br-cAMP and TPA (an artificial PKC promoter) increased $Ca^{2+}$ uptake by 25.51% and 16.47%, respectively, compared with the control. In conclusion, $E_2-BSA$ combined with calcitropic hormones regulated $Ca^{2+}$ uptake partially via cAMP and PKC-dependent mechanisms in renal proximal tubule cells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.1
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• pp.7-10
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• 1975

The catches of mackerel by monofilament and multifilament net were compared by means of $x^2$ and t-test method. In order to improve the netting twine of drift nets, 6 shoots 5 different mesh and nylon-monofilament netting twines $(B\times2,\;C\;D,\;F,)$ and 2 shoe nylon-multifilament $(A\times2)$ which are using near the Jeju Island in contemporary days were used for the experiment. These gill no were connected in order of A, ,B, C, A, B, E, F and operated fly fishing boat Taeann Ho (7T) near sea of Jeju Ialand from May 1974 to August 1974. The results obtained are as follows: 1. B type nylon-monofilament gill nets were superior to nylon-multifilament gill nets in catch according to the result of $X^2$ test and t-test, and the catch ratio was $M_A:\;M_B=1:1.8$. 2. 75mm mesh size C, D nylon-monofilament gill nets were superior to 85mm mesh size nylonmonofilament gill nets, and their catch ratio were E, F: C, D=1:2.8. 3. The catch ratio C, D and E, F type nets were compared by means of t-teat, however could not recognized their relationship.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2034-2042
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• 2015

A one-pot process of enzymatic synthesis of deoxythymidine-5'-triphosphate (5'-dTTP) employing whole cells of recombinant Escherichia coli coexpressing thymidylate kinase (TMKase) and acetate kinase (ACKase) was developed. Genes tmk and ack from E. coli were cloned and inserted into pET28a(+), and then transduced into E. coli BL21 (DE3) to form recombinant strain pTA in which TMKase and ACKase were simultaneously overexpressed. It was found that the relative residual specific activities of TMKase and ACKase, in pTA pretreated with 20 mM ethylene diamine tetraacetic acid (EDTA) at 25℃ for 30 min, were 94% and 96%, respectively. The yield of 5'-dTTP reached above 94% from 5 mM deoxythymidine 5'-monophosphate (5'-dTMP) and 15 mM acetyl phosphate catalyzed with intact cells of pTA pretreated with EDTA. The process was so effective that only 0.125 mM adenosine-5'-triphosphate was sufficient to deliver the phosphate group from acetyl phosphate to dTMP and dTDP.

• Ocean and Polar Research
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• v.40 no.3
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• pp.115-125
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• 2018

Production from copepodite IV to adult of two euchaetid species Euchaeta plana and Paraeuchaeta russelli was measured at the southeastern sea of Korea from April to November, 2014. The mean density was $2.0ind\;m^{-3}$ for E. plana and $4.1ind\;m^{-3}$ for P. russelli, with the high contribution of copepodite V to total density. The densities of total individuals, adult females and eggs were highest in November for both species. The mean egg production rate (EPR) was $1.7eggs\;female^{-1}\;d^{-1}$ for E. plana and $3.1eggs\;female^{-1}\;d^{-1}$ for P. russelli. Both of them showed the highest EPR in September but zero EPR in summer. The mean weight-specific EPR was $0.038d^{-1}$ for E. plana and $0.079d^{-1}$ for P. russelli. The mean total production rates of E. plana and P. russelli were $5.3{\mu}g\;C\;m^{-3}\;d^{-1}$ and $17.8{\mu}g\;C\;m^{-3}\;d^{-1}$, respectively, with the largest production in November. The mean Production/Biomass ratio was $0.06d^{-1}$ for E. plana and $0.07d^{-1}$ for P. russelli, with its peak in September for both. The total production of E. plana and P. russelli was positively correlated with the density of a copepod Oncaea venusta, rather than chl-a concentration, indicating that the two copepods might be carnivores. This study evaluates the contribution of euchaetids to the copepod community in the southeastern sea of Korea.

• Bulletin of the Korean Mathematical Society
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• v.49 no.4
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• pp.885-898
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• 2012

Let m, n, r be nonzero fixed positive integers, R a 2-torsion free prime ring, Q its right Martindale quotient ring, and L a non-central Lie ideal of R. Let D : $R{\rightarrow}R$ be a skew derivation of R and $E(x)=D(x^{m+n+r})-D(x^m)x^{n+r}-x^mD(x^n)x^r-x^{m+n}D(x^r)$. We prove that if $E(x)=0$ for all $x{\in}L$, then D is a usual derivation of R or R satisfies $s_4(x_1,{\ldots},x_4)$, the standard identity of degree 4.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.3
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• pp.26-36
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• 2012

Minimizing the cylinder wear and the consumption rate of cylinder oil in a large two-stroke diesel engine is of great economic importance. A motor-driven cylinder lubricator for Sulzer RT-flex large two-stroke diesel engines developed by authors is in need of mounting a quill system to lubricate cylinder parts for a smooth operation. In order to apply the common-rail lubricating system to the developed cylinder lubricator as the second research stage, the mechanical quill system with a progressively quantitative distributor (M.D.S.) is improved in the electronically controlled quill system with an accumulating distributor (E.D.S.). In this study, the effects of lubricator motor speed, plunger stroke and cylinder back pressure on oil feed rate and inequality rate are experimentally investigated by applying E.D.S. to the developed cylinder lubricator. It is found that the oil feed rate of E.D.S. is higher than that of M.D.S. because of the increase of delivery speed and volume by changing the role of accumulator in the same experimental condition. It can be also shown that, in E.D.S., the inequality rate is decreased a little or hardly unchanged as the cylinder back pressure and plunger stroke is elevated, while the inequality rate increased in M.D.S.. The inequality rates of E.D.S. and M.D.S. are lowered as the lubricator motor speed is increased.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.593-598
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• 2004

The arsenical resistance (ars) operon was cloned from a 67-kilobase pair (kb) plasmid, which was previously shown to be responsible for arsenic salts resistance in K. oxytoca D12. When plasmid pAE48, carrying the ars operon, was transformed into E. coli, transformed cells displayed enhanced survival in the presence of 4 mM arsenite, 50 mM arsenate, or 0.4 mM antimonite. The nucleotide sequence of the 5.6-kb fragment encoding arsenical resistance revealed five open reading frames (ORFs), which were predicted to encode polypeptides of 12.8 (arsR), 13.4 (arsD), 62.6 (arsA), 45 (arsB), and 16.7 (arse) kilodaltons (kDa). Each ORF was preceded by a ribosome binding site. A putative promoter-like sequence was identified upstream of arsR, and a possible termination site was found downstream of arsC. When the deduced amino acid sequences of the K. oxytoca Dl2 Ars proteins were compared with the amino acid sequences of the E. coli R773 Ars proteins, a significant amino acid similarity was observed (87.9％ for ArsR, 89.2％ for ArsD, 83.2％ for ArsA, 92.6％ for ArsB, and 91.3％ for ArsC), suggesting an evolutionary relationship of the ars genes of E. coli plasmid R773 and K. oxytoca Dl2.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.809-819
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• 1996

This study was conducted to identify the effects of caffeine or combinations of caffeine and iron or vitamin E on the lipid and protein components in the MDBK(Mardin-Darby Bovine Kidney) cells. For the In vitro test, MDBK cells in ${\alpha}$-MEM(Minimum Essential Medium) were divided into 4 treatment groups according to drug types and dosages as follows; the control(group A), group B was treated with 0.3mM caffeine, group C was treated with 0.3mM caffeine and 0.3mM ferric chloride, group D was treated with 0.3mM caffeine and 0.3mM vitamin E. Those groups were further divided into 5 subgroups according to the time lapsed(control, 4hrs, 8hrs, 24hrs and 48hrs lapsed group). The concentrations of the carbonyl group and malondialdehyde(MDA) and the patterns of the SDS-PAGE(Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis) and fatty acid compositions were analyzed to determine the oxidative damages and metabolic changes on the lipid and protein components in the MDBK cells. The results obtained from this study were summarized as follows; 1. The concentrations of carbonyl group and malondialdehyde in MDBK cells of group C were significantly higher(p<0.01) in comparison to the control, and increased according to the time lapsed. But the results of groups B and D were little different in comparison to the group C. 2. As the analytical results of fatty acid compositions in MDBK cells, the proportions of palmitoleic acid and linoleic acid in groups B, C and D were lower in comparison to the control, while the proportion of arachidonic acid in groups B, C and D were significantly higher(p<0.01) in comparison to the control. 3. In order to determine the oxidative damages to the protein in MDBK cells, the patterns of the SDS-PAGE were examined and the patterns of SDS-PAGE in groups C and D were significantly different between 43kd and 200kd of molecular weight.