• Journal of the Korean Chemical Society
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• v.40 no.5
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• pp.341-346
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• 1996

Electrochemical determination of iodide was carried out by stripping voltammetry with a $(Cin)Cu(NO_3)_2$ modified-carbon paste electrode. Iodide was coordinated onto the electrode surface containing $(Cin)Cu(NO_3)_2$ via ion exchange. The oxidation peak potential of incorporated iodide was ＋0.72 V. The optimum analytical conditions for the determination of iodide were investigated using linear sweep voltammetry. Optimum conditions for the electrochemical determination of iodide were as follows: i) A predeposition solution was 0.1 M $KNO_3.$ ii) The deposition time was 10 min. iii) The composition of the electrode was 40% (w/w). The detection limit for iodide was $1.0{\times}10^{-6}M$ and the relative standard deviation was ${\pm}5.5%\;in\;2.0{\times}10^{-5}M$(four repetitions). The interference effect of other anions were also investigated. $Cl^-,\;Br^-,\;C_2O_4^{2-},\;and\;ClO_4^-$ ions do not interfere for the determination of iodide. When $SCN^-$ was added to the deposition solution, the oxidation peak current of iodide ion was decreased roughly 32%.

• Journal of Environmental Science International
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• v.2 no.1
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• pp.61-72
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• 1993

Result of this study indicate that two criteria must be met in order to have effective macrocycle-mediated transport in these emulsionsystem. First, one must effective extraction of the post transition metals, $Cd^{2+}$. $Pb^{2+}$ and $Hg^{2+}$ , into toluene membrane. The effectiveness of this extraction is greatest if log K values for the metal-macrocycle interaction is large. Second, the ratio of the log K values for the metal ion-receiving phase to the metal ion-macrocycle interaction must be large enough to ensure quantitative stripping of the metal ion at the toluene phase interface. Control of the first step can be obtained by appropriate selection of macrocycle donor atom, substituents, and cavity radius. The second step can be controlled by selecting the proper complexing agent for inclusion in the receiving phase. The order of the transport, when using the several $A^-$ species such as $SCN^-$, $1^-$, $Br^-$ and $Cl^-$ is the order of the changing degree of solvation for $A^-$ and the transport of the metals is also affected by the control of concentration for receiving species because of solubility-differences. In this study, we can seperate each single metal ion from the mixture of $Cd^{2+}$, $Pb^{2+}$, and $Hg^{2+}$ ions by using the toluene membranes controlled by optimized conditions. Transport of the single metal is also very good, and alkaline and alkaline earth metals as interferences ions did not affect the seperation of the metals in this macrocycle-liquid membrances but transition metal ions were partially affected as interferences for the post transition metal ions.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.5
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• pp.259-264
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• 2004

Cytolysin produced by Vibrio vulnificus has been incriminated as one of the important virulence determinants in V. vulnificus infection. Ion selectivity of cytolysin-induced pores was examined in a CPAE cell, a cell line of pulmonary endothelial cell, using inside-out patch clamp techniques. In symmetrical NaCl concentration (140 mM), intracellular or extracellular application of cytolysin formed ion-permeable pores with a single channel conductance of $37.5{\pm}4.0$ pS. The pore currents were consistently maintained after washout of cytolysin. Replacement of $Na^+$ in bath solution with monovalent ions $(K^+,\;Cs^+\;or\;TEA^+)$ or with divalent ions $(Mg^{2+},\;Ca^{2+})$ did not affect the pore currents. When the NaCl concentration in bath solution was lowered from 140 to 60 and 20 mM, the reversal potential shifted from 0 to -11.8 and -28.2 mV, respectively. The relative permeability of the cytolysin pores to anions measured at $-40\;mV\;was\;Cl^-\;=\;NO_2^-\;{\geq}\;Br^-\;=\;I^-\;> \;SCN^-\;>\;acetate^-\;>\;isethionate^-\;>\;ascorbic acid^-\;>\;EDTA^{2-},$ in descending order. The cytolysin-induced pore current was blocked by $CI^-$ channel blockers or nucleotides. These results indicate that V. vulnificus cytolysin forms anion-selective pores in CPAE cells.

• Journal of the Korean Society of Safety
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• v.10 no.4
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• pp.47-59
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• 1995

The perchlorate, thiocyanate, and nitrate ion-selective PVC membrance electrode for measuring hazardous anion in waste water were developed by incorporating the quaternary ammonium salts as active material. Ion-selective characteristics in waste water were studied by the useful pH range, the selective coefficients to various interfering anions, and the stability of electrode potential. DBP was best as a plasticizer. The effect of the membrane thickness on the electrode characteristics was improved with decreasing the membrane thickness, but below the optimum membrane thickness the electrode exhibited an inverse trend. The electrode potential of perchlorate, thiocyanate, and nitrate electrode with TDDA, as active material, was stable within the pH range 4-11, 3-12, and 4-10 repectively. And the long-term potential stability of these electrodes were 3.0, 3.5, and 3.5 months respectively. The order of the selectivity coefficients was as shown below ; $ClO_4{^-}$ > $SCN^-$ > $I^-$ > $NO_3{^-}$ > $Br^-$ > $CN^-$ > $F^-$ > $Cl^-$ > $Ac^-$ > $H_2PO_4{^-}$, $SO_4{^-}$.

• Journal of Chest Surgery
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• v.33 no.9
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• pp.734-737
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• 2000

Background: McKeown first described two autopsy cases of esophageal small cell carcinoma (SMC) in 1952; about 230 cases have since been reported in the literature. Small cell carcinoma has been reported to account for 0.4% to 7.6% of all esophageal malignancies. SMC of the esophagus as regarded as having a poor prognosis with frequent systemic dissemination. Choice of treatment remains controversial. Material and Method: From August 1987 to December 1998, a review of the records and histologic sections of 8 patients with primary small cell carcinoma of the esophagus seen in 11 years was undertaken. Result: Small cell carcinoma of the esophagus constituted 1.5% of all esophageal cancers. The median age was 61.5 years(range from 42 to 71 years). Seven patients were male, tumor was mainly located in the middle and lower thirds(6 cases) of the esophagus. Pure SMC is 5 cases, and mixed SMC is 3 cases. Operative procedure were as follow: transthoracic esophagectomy with thoracic or cervical reconstructon in 7 patients, transhiated esophagectomy with cervical reconstruction in one. The operative death was none. Adjuvant chemotherapy was performed in 7 patients except one who had poor general condition. Recurrence was observed in 4 patients(mediastinal LN, abdominal LN, SCN, bone). The overall median survival was 15.9 months. Only one patient survived for more than 5 years. Conclusion: We considered that esophageal SMC should be regarded as a systemic disease, and multimodality treatment including chemotherapy should be used. Surgery may be offered in selected patients to manage local disease as part of a chemotherapy based treatment program.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.386-392
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• 1998

Reproduction of the soybean cyst nematode (SCN), Heterodera glycines Ichinohe on the susceptible soybean cultivar, Lee 74, was significantly reduced by pre-, post- and simultaneous treatments of acetylsalicylic acid (ASA, aspirin). The control efficiencies were 60%, 64% and 87% for pre-, post- and simultaneous treatments, respectively. ASA had no significant effect on the survival of 2nd stage juveniles and their penetration into the soybean root tissues, but significantly inhibited the early stage nematode growth in the roots. Syncytia were formed 2∼3 days after inoculation in the susceptible soybean without ASA treatment, characterized by dense cytoplasm and increased cellular organelles such as mitochondria and endoplasmic reticulum. The nematode stylet was penetrated into the syncytial cell, and feeding tube was formed at the nematode stylet was penetrated into the syncytial cell, and feeding tube was formed at the nematode stylet entry. However, in the ASA treatments, syncytium was not formed or degenerated, depending on the root tissues. In the pre-treatments of ASA, nematode stylets did not penetrate into cells, showing callose-like cell wall thickening formed at the nematode probing sites, or retracted from the infected cells. The stylet penetration sites of syncytial cells appeared to be sealed off with fibrillar materials. With post-treatment of ASA, syncytia formed by the nematode were degenerated, characterized by degradation of syncytial cytoplasm.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.611-627
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• 2017

For enhancing the coverage of wireless networks and increasing the spectrum efficiency, small cell networks (SCNs) are considered to be one of the most prospective schemes. Most of the existing literature on resource allocation among non-cooperative small cell base stations (SBSs) has widely drawn close attention and there are only a small number of the cooperative ideas in SCNs. Based on the motivation, we further investigate the cooperative approach, which is formulated as a coalition formation game with power control algorithm (CFG-PC). First, we formulate the downlink sub-channel resource allocation problem in an SCN as a coalition formation game. Pareto order and utilitarian order are applied to form coalitions respectively. Second, to achieve more availability and efficiency power assignment, we expand and solve the power control using particle swarm optimization (PSO). Finally, with our proposed algorithm, each SBS can cooperatively work and eventually converge to a stable SBS partition. As far as the transmit rate of per SBS and the system rate are concerned respectively, simulation results indicate that our proposed CFG-PC has a significant advantage, relative to a classical coalition formation algorithm and the non-cooperative case.

• Animal cells and systems
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• v.16 no.1
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• pp.27-33
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• 2012

The suprachiasmatic nucleus (SCN) of the teleost hypothalamus contains a central circadian pacemaker, which adjusts circadian rhythms within the body to environmental light-dark cycles. It has been shown that exposure to darkness during the day causes phase shifts in circadian rhythms. In this study, we examined the effect of exposure to darkness on the mRNA expression levels of two circadian clock genes, namely, $Period2$ ($Per2$) and $Cryptochrome1$ ($Cry1$), and the rate-limiting enzyme in melatonin synthesis, arylalkylamine $N$-acetyltransferase-2 (Aanat2), in the pineal gland of olive flounder, $Paralichthys$ $olivaceus$. The expression of these genes showed circadian variations and was significantly higher during the dark phase. These changes may be involved in the mechanism of dark-induced phase shifts. Furthermore, this study suggests that olive flounder may be a teleost model to investigate the localization and function of circadian oscillators.

• Bulletin of the Korean Chemical Society
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• v.28 no.8
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• pp.1311-1316
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• 2007

To develop photo-sensitizers for dye-sensitized solar cells (DSCs) used in harvesting sunlight and transferring solar energy into electricity, we synthesize novel Ru(II) polypyridyl dyes and describe their characterization. We also investigate the photo-electrochemical properties of DSCs using these sensitizers. New dyes contain chromophore unit of dafo (4,5-diazafluoren-9-one) or phen-dione (1,10-phenanthroline-5,6-dione) instead of the nonchromophoric donor unit of thiocyanato ligand in cis-[RuII(dcbpy)2(NCS)2] (dcbpy = 4,4'-dicarboxy- 2,2'-bipyridine) coded as N3 dye. For example, the photovoltaic data of DSCs using [RuII(dcbpy)2(dafo)](CN)2 as a sensitizer show 6.85 mA/cm2, 0.70 V, 0.58 and 2.82% in short-circuit current (Jsc ), open-circuit voltage (Voc), fill factor (FF) and power conversion efficiency (Eff), which can be compared with those of 7.90 mA/ cm2, 0.70 V, 0.53 and 3.03% for N3 dye. With the same chelating ligand directly bonded to the Ru metal in the complex, the CN ligand increases the Jsc value by double, compared to the SCN ligand. The extra binding ability in these new dyes makes them more resistant against ligand loss and photo-induced isomerization within octahedral geometry.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.4
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• pp.298-305
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• 1998

The PVC membrane electrode for measuring perchlorate ion was developed by incorporating various quaternary ammonium sallts. The effect of chemical structure, the content of active material, the kind of plasticizers, and the membrane thickness on the electrode characteristic such as the linear response range and Nernstian slope of the electrode were studied. It was obtained that the effect of the chemical structure of an active material on the electrode characteristics was improved with increasing the alkyl chain length of the quarternary ammonium salts in the ascending order of Aliquat 336P, TOAP, TDAP, and TDDAP. The optimum membrane composition was 9.09wt% of TDDAP, 30.3wt% of PVC, and 60.6wt% of plasticizer(DBP). And the optimum membrane thickness was 0.45mm at this composition. Under the above condition, the linear response range was $10^{-1}~1.2\times10^{-6}$M, and the detection limit was $5.1\times10^{-7}$M with the Nernstian slope of 57mV/decade of activity of perchlorate ion. The electrode potential was stable within the pH range from 4 to 11. The selectivity coefficient was as shown below: $SCN^->I^-NO_3^->Br^->ClO_3^->F^->Cl^->SO_4^{2-}$