• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.575-577
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• 1999

In this study, the PPPI(Plasma Polymerized Phenyl Isothiocyanate) resist thin film was manufactured in accordance with the plasma polymerization method and after exposing it to an electron beam, a pattern was formed by plasma etching. With the FT-IR(Fourier transform-infrared spectrometry) analysis, it was confirmed that the PI(Phenl Isothiocyanate) monomer was successsfully produced into a thin film by the plasma. The polymerization rate of the thin film was 450~ 1012($\AA$/min) to 100-200(W) discharge power and 120-12($\AA$/min) to 0.1 ~0.4[torr] system pressure.

• 한국염색가공학회지
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• 제16권5호
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• pp.35-41
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• 2004

Poly(ethylene terephthalate), polyimide(Kapton), and polypropylene surfaces were modified with argon low temperature plasma by RF glow discharge at 240m Torr, 40W to investigate the surface morphological changes due to the plasma treatment using atomic force microscopy(AFM). Analysis of the AFM images and Ra(average roughness) revealed that the plasma treatment resulted in significant ablation on the surfaces. The morphological changes and surface roughness, however, were different depending on material characteristics such as heat stability, presence of amorphous region, swelling phenomenon, and molecular structure of repeating unit. It was assumed that polypropylene due to its tertiary hydrogen was ablated easily compared to poly(ethylene terephthalate), and that polyimide was more resistant to the ablation than PET due to rigid skeleton of imide and stable phenyl ring structure.

• The Journal of Advanced Prosthodontics
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• 제12권2호
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• pp.75-82
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• 2020

PURPOSE. The aim of this study was to investigate the shear bond strength of luting cements used with implant retained restorations on to titanium specimens after different surface treatments. MATERIALS AND METHODS. One hundred twenty disc shaped specimens were used. They were divided into three groups considering the surface treatments (no treatment, sandblasting, and oxygen plasma treatment). Water contact angle of specimens were determined. The specimens were further divided into four subgroups (n=10) according to applied cement types: polycarboxylate cement (Adhesor Carbofine-AC), temporary zinc oxide free cement (Temporary CementZOC), non eugenol provisional cement for implant retained prosthesis (Premier Implant Cement-PI), and non eugenol acrylic-urethane polymer based provisional cement for implant luting (Cem Implant Cement-CI). Shear bond strength values were evaluated. Two-way ANOVA test and Regression analysis were used to statistical analyze the results. RESULTS. Overall shear bond strength values of luting cements defined in sandblasting groups were considerably higher than other surfaces (P<.05). The cements can be ranked as AC > CI > PI > ZOC according to shear bond strength values for all surface treatment groups (P<.05). Water contact angles of surface treatments (control, sandblasting, and plasma treatment group) were 76.17° ± 3.99, 110.45° ± 1.41, and 73.80° ± 4.79, respectively. Regression analysis revealed that correlation between the contact angle of different surfaces and shear bond strength was not strong (P>.05). CONCLUSION. The retentive strength findings of all luting cements were higher in sandblasting and oxygen plasma groups than in control groups. Oxygen plasma treatment can improve the adhesion ability of titanium surfaces without any mechanical damage to titanium structure.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1393-1400
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• 2009

A bacteriocin-producing strain PI80 was isolated from the gut of Penaeus indicus (Indian white shrimp) and identified as Streptococcus phocae PI80. The bacteriocin was purified from a culture supernatant to homogeneity as confirmed by Tricine SDS-PAGE. Reverse-phase HPLC analysis revealed a single active fraction eluted at 12.94 min, and MALDI-TOF mass spectrometry analysis showed the molecular mass to be 9.244 kDa. This molecular mass does not correspond to previously described streptococcal bacteriocins. The purified bacteriocin was named phocaecin PI80 from its producer strain, as this is the first report of bacteriocin production by Streptococcus phocae. The bacteriocin exhibited a broad spectrum of activity and inhibited important pathogens: Listeria monocytogenes, Vibrio parahaemolyticus, and V. fischeri. The antibacterial substance was also sensitive to proteolytic enzymes: trypsin, protease, pepsin, and chymotrypsin, yet insensitive to catalase, peroxidase, and diastase, confirming that the inhibition was due to a proteinaceous molecule (i.e., the bacteriocin), and not due to hydrogen peroxide or diacetyl. Phocaecin PI80 moderately tolerated heat treatment (up to $70^{\circ}C$ for 10 min) and resisted certain solvents (acetone, ethanol, and butanol). A massive leakage of $K^+$ ions from E. coli $DH5\alpha$, L. monocytogenes, and V. parahaemolyticus was induced by phocaecin PI80, as measured by Inductively Coupled Plasma Optical Emission Spectrometry (ICPOES). Therefore, the results of this study show that phocaecin PI80 may be a useful tool for inhibiting L. monocytogenes in seafood products that do not usually undergo adequate heat treatment, whereas the cells of Streptococcus phocae PI80 could be used to control vibriosis in shrimp farming.

• Molecules and Cells
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• 제39권4호
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• pp.322-329
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• 2016

Voltage-gated $Ca^{2+}$ ($Ca_V$) channels are dynamically modulated by Gprotein-coupled receptors (GPCR). The $M_1$ muscarinic receptor stimulation is known to enhance $Ca_V2.3$ channel gating through the activation of protein kinase C (PKC). Here, we found that $M_1$ receptors also inhibit $Ca_V2.3$ currents when the channels are fully activated by PKC. In whole-cell configuration, the application of phorbol 12-myristate 13-acetate (PMA), a PKC activator, potentiated $Ca_V2.3$ currents by ~two-fold. After the PMA-induced potentiation, stimulation of $M_1$ receptors decreased the $Ca_V2.3$ currents by $52{\pm}8%$. We examined whether the depletion of phosphatidylinositol 4,5-bisphosphate ($PI(4,5)P_2$) is responsible for the muscarinic suppression of $Ca_V2.3$ currents by using two methods: the Danio rerio voltage-sensing phosphatase (Dr-VSP) system and the rapamycin-induced translocatable pseudojanin (PJ) system. First, dephosphorylation of $PI(4,5)P_2$ to phosphatidylinositol 4-phosphate (PI(4)P) by Dr-VSP significantly suppressed $Ca_V2.3$ currents, by $53{\pm}3%$. Next, dephosphorylation of both PI(4)P and $PI(4,5)P_2$ to PI by PJ translocation further decreased the current by up to $66{\pm}3%$. The results suggest that $Ca_V2.3$ currents are modulated by the $M_1$ receptor in a dual mode-that is, potentiation through the activation of PKC and suppression by the depletion of membrane $PI(4,5)P_2$. Our results also suggest that there is rapid turnover between PI(4)P and $PI(4,5)P_2$ in the plasma membrane.

• 분석과학
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• 제29권1호
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• pp.10-18
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• 2016

Phosphodiesterase(PDE)는 세포내에서 cAMP를 분해하는 효소로 세포의 신호 전달에 중요한 기능을 수행하는 것으로 알려져 왔다. 이전의 연구를 통해 군소에서 클로닝된 PDE4 long-form의 N-말단에 위치하는 16개 아미노산만으로 충분히 원형질막에 타기팅됨을 알 수 있었다. 본 연구에서는 ApPDE4의 N-말단 16개(L(N16))를 주형으로 해서 9-11번째와 15번째 아미노산들(RHW-C)을 무작위적으로 아마노산에 돌연변이를 주어서 세포내 타기팅에 미치는 영향을 분석해 보았다. 본 연구를 통해 원형질막과 골지체로 타기팅되는 돌연변이체들과 골지체로만 타기팅되는 돌연변이체들과, 소포체와 골지체로 동시에 타기팅되는 돌연변이체들과, 세포질에만 위치하는 돌연변이체들을 얻을 수 있었다. 또한, 이러한 타기팅에 palmitoylation이 영향을 주는지 확인하기 위해 palmitoylation 억제제인 2-BR을 처리해보니 대부분의 돌연변이체에서 원형질막 타기팅이 사라지는 것을 확인하였다. 이를통해 palmitoylation이 ApPDE4 돌연변이체들의 원형질막 타기팅에 중요하다는 사실을 확인할 수 있었다. 또한, 이들 돌연변이체들중 골지체로만 타기팅되는 L(N16,C3S/VV/G)-mRFP와 L(N16,C3S/LFS/R)-mRFP와 L(N16,EPL/R)-mRFP들의 경우는 골지체 타기팅에 인지질 중에 하나인 PI4P가 중요한 역할을 하는 것을 알 수 있었다.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권1호
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• pp.42-42
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• 2004

Recently, Pi2 pulsations during the intervals of extremely quiet magnetospheric conditions (Kp = 0$\^$+/) have been reported by Sutcliffe and Lyons (2002). The authors observed several Pi2 bursts occurred simultaneously at high (magnetic latitude = 71$^{\circ}$) and low (42$^{\circ}$) latitudes during the absence of magnetospheric substorms and found that the bursts are strongly correlated with poleward boundary intensifications (PBIs), associated with enhancements of energetic ion fluxes observed by the Geotail satellite at Xgsm - -12 Re to -17 Re and Ygsm - 12 Re to 10 Re in the plasma sheet. (omitted)

• Journal of Magnetics
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• 제12권1호
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• pp.27-30
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• 2007

Experimental evidence suggests that spin pinning conditions for standing spin mode in polycrystalline $Ni_{84}Fe_{16}$ alloy film, is confirmed using the four categories of Camley et al. and the value of q$\bot$ for the pinning conditions, this was achieved by performing Brillouin light scattering measurements. The value of q$\bot$ was observed, in order to increase at a rate of $\pi$/2 with an increasing mode number. With this condition, the coexistence of standing spin wave modes was shown, with intermediate pinning, in addition to free and strong pinning. The values for spin-wave-stiffness constant ($D_B$), g-factor (g), and surface magnetization (4$\pi$M) of the Permalloy film were obtained from the results of BLS, and determined to be $D_B=1.85{\pm}0.05Oecm^2$, $g=2.11{\pm}0.02$, and 4$\pi$M=8.7 kG, respectively.

• Journal of Microbiology and Biotechnology
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• 제19권12호
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• pp.1635-1643
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• 2009

The aim of this study was to provide new insight into the mechanism whereby the housekeeping enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) locates to cell walls of Lactobacillus plantarum 299v. After purification, cytosolic and cell wall GAPDH (cw-GAPDH) forms were characterized and shown to be identical homotetrameric active enzymes. GAPDH concentration on cell walls was growth-time dependent. Free GAPDH was not observed on the culture supernatant at any time during growth, and provoked cell lysis was not concomitant with any reassociation of GAPDH onto the cell surface. Hence, with the possibility of cw-GAPDH resulting from autolysis being unlikely, entrapment of intracellular GAPDH on the cell wall after a passive efflux through altered plasma membrane was investigated. Flow cytometry was used to assess L. plantarum 299v membrane permeabilization after labeling with propidium iodide (PI). By combining PI uptake and cw-GAPDH activity measurements, we demonstrate here that the increase in cw-GAPDH concentration from the early exponential phase to the late stationary phase is closely related to an increase in plasma membrane permeability during growth. Moreover, we observed that increases in both plasma membrane permeability and cw-GAPDH activity were delayed when glucose was added during L. plantarum 299v growth. Using a double labeling of L. plantarum 299v cells with anti-GAPDH antibodies and propidium iodide, we established unambiguously that cells with impaired membrane manifest five times more cw-GAPDH than unaltered cells. Our results show that plasma membrane permeability appears to be closely related to the efflux of GAPDH on the bacterial cell surface, offering new insight into the understanding of the cell wall location of this enzyme.

• Journal of Korean Vacuum Science & Technology
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• 제4권1호
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• pp.1-5
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• 2000

The C 1s photoelectron energy loss spectra of tris (8-hydroxy-quinoline) aluminum (Alq$_3$) and N,N'-diphenyl-N,N'-bis (3-methyl phenyl)-1,1'-bi-phenyl-4,4'-diamine (TPD) thin films have been investigated. Two major loss structures, namely the plasmon dominated loss lines and shake-up satellites, have been observed. The shake-up spectrum of the C 1s photoelectron line is directly related to the $\pi$-$\pi$$\^$*/ energy gap of the molecule which plays an important role in organic electroluminescent materials. The molecular orbitals of Alq$_3$ and TPD and their major components, quinolime and benzene, have been calculated with the AMI semi-empirical method. The amount of the plasma-dominated loss of Alq$_3$ and TPD, which has to do with the delocalization of electrons through the molecule, was about 24 eV, alike in both cases. The main peak of the C 1s shake-up spectrum of Alq$_3$ and TPD, however, was 5.2 eV and 6.8 eV respectively. It was found that the main shake-up peak reflects more the local $\pi$\longrightarrow$\pi$$\^$*/ transition of quinoline and benzene component rather than the excitation of the whole molecule of Alq$_3$ and TPD. The C 1s shake-up spectra, however, revealed some correlation with the optical energy gap of the organic eletroluminescent materials.