• Tuberculosis and Respiratory Diseases
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• v.59 no.4
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• pp.427-431
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• 2005

Lambert-Eaton myasthenic syndrome (LEMS), a rare autoimmune neurological syndrome, is caused by defects in the secretion of acetylcholine from the presynaptic membrane, and is associated with the destruction of voltage gated calcium channels (VGCC) in the neuromuscular junction. LEMS can be confirmed by repetitive nerve stimulation and by the clinical symptoms, which are characterized by proximal muscle weakness in the lower extremities, decreased deep tendon reflexes and autonomic dysfunctions. In about 60% of patients with this disorder, underlying cancer-small cell lung cancer may be detected. Clinical symptoms may precede the diagnosis of malignancy, with the early diagnosis and treatment of the underlying malignancy being possible through the diagnosis of LEMS. A case of LEMS, with positive VGCC antibodies, in a 48-year-old man, which improved after chemotherapy of the underlying small cell lung cancer, is reported.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.115-130
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• 2002

Signal transduction refers to the processes by which cells perceive the environment and/or internal status. In many physiological responses, cellular signals are activated by the transducers attached to the cell surface plasma membrane in response to chemical modulators. Advances in information technology are required in the pharmaceutical sciences to screen and explore the potential therapeutic agents. (omitted)

• Advances in Energy Research
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• v.2 no.2
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• pp.73-84
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• 2014

Fuel cells of proton exchange membrane type (PEMFC) working with hydrogen in the anode and ambient air in the cathode ('air breathing') have been prepared and characterized. The cells have been studied with variable thickness of the cathode catalyst layer ($L_{CL}$), maintaining constant the platinum and ionomer loads. Polarization curves and electrochemical active area measurements have been carried out. The polarization curves are analyzed in terms of a model for a flooded passive air breathing cathode. The analysis shows that $L_{CL}$ affects to electrochemical kinetics and mass transport processes inside the electrode, as reflected by two parameters of the polarization curves: the Tafel slope and the internal resistance. The observed decrease in Tafel slope with decreasing $L_{CL}$ shows improvements in the oxygen reduction kinetics which we attribute to changes in the catalyst layer structure. A decrease in the internal resistance with $L_{CL}$ is attributed to lower protonic resistance of thinner catalyst layers, although the observed decrease is lower than expected probably because the electronic conduction starts to be hindered by more hydrophilic character and thicker ionomer film.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.9
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• pp.913-919
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• 1991

For an elementary study of the molecular electronic devices, in this study, N-alkylpyridinium(TCNQ) (1:1) and (1:2) complexed were synthesized. These complexes were verified by the UV, IR and the elemental analysis. Deposition of the LB films were verified by the reciprocal capacitance, UV absorbance and decresement area of Langmuir fims as functions of number of layers. The internal voltage of LB membrane devices fabricated with Y-type resides in 100-300mV. Finally, it seemed that self-polarization of LB membrance generates internal voltage.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2939-2942
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• 2010

A new high-temperature pH sensor has been successfully developed by reforming the internal reference systems of the pH sensors based on oxygen-ion conducting ceramic membrane. The conventional internal reference system, a mixture of Ni and NiO, has been replaced with partially oxidized Ni powders, where Ni and NiO coexist on the surface of particles, in order to avoid the cumbersome mixing step of Ni and NiO particles. The partially oxidized Ni particles were made by oxidizing Ni under air atmosphere at $600^{\circ}C$ and characterized by X-ray diffraction (XRD) and FTIR spectroscopy. The viability of the pH sensor developed was assessed in boric acid (1000 ppm-B)/ lithium hydroxide (1 to 3 ppm-Li) buffer solutions at $280^{\circ}C$. The pH sensor showed excellent accuracy with a small error less than ${\pm}0.2$ pH units.

• Journal of Veterinary Clinics
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• v.25 no.6
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• pp.518-522
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• 2008

An approximately 8-month-old, 2.61 kg, male Siamese kitten was referred with primary complaints of a 1-week history of respiratory distress, exercise intolerance and dyspnea. Diagnostic studies identified III/VI systolic murmur in the cardiac auscultation, right ventricular enlargement patterns in the electrocardiogram, pleural effusion and right-sided cardiomegaly in the thoracic radiography, and right marked ventricular dilatation, right atrial enlargement, atrial septal defect and abnormal left atrium divided by fibromuscular membrane. Based on these findings, the case was diagnosed as cor triatriatum sinistrum complicated with an ostium primum atrial septal defect. The cat was rescued with furosemide, nitroglycerine, oxygen supplement and fluid removal from pleural cavity.

• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.6-12
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• 1998

A FET(Field Effect Transistor) type dissolved $CO_2$ sensor based on Severinghaus type $CO_2$ sensor was fabricated by the photolithographic process. The sensor consists of Ag/AgCl reference electrode and membranes (hydrogel membrane and $CO_2$ gas permeable membrane) on the pH-ISFET base chip. Ag/AgCl reference electrode was fabricated as follows. Ag layer was thermally evaporated and then its upper surface was chemically chloridized into the AgCl. The hydrogel used as an internal electrolyte solution was fabricated by a photolithographic method using 2-hydroxyethyl methacrylate(HEMA) and acrylamide. $CO_2$ permeable membrane on the top of the hydrogel layer was formed by photolithographic process with UV-oligomer. The FET type $pCO_2$ sensor fabricated by photolithographic method showed good linearity within the concentration range of $10^{-3}{\sim}10^0mole/{\ell}$ of dissolved $CO_2$ in aqueous solution with high sensitivity.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.943-949
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• 1998

This study is concerned with the treatment of landfill leachate by carrier meditated emulsion. Using the batch operation, the optimum conditions for the removal of anionic and cationic materials were obtained. The landfill leachate from the plant was experimented under these conditions. The experimental variables were surfactant (Arlacel80) concentration and carrier(Aiquat336, DEHPA) concentration in membrane phase and counter ion concentration in internal phase. More than 80%(COD) of landfill leachate component could be removed within 12 minutes. The most crucial experimental variable for the removal efficiency was carrier concentration in membrane phase. In the other variables, the reaction time was more effected than the removal efficiency.

• Membrane Journal
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• v.26 no.1
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• pp.1-13
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• 2016

Fuel cells are regarded as a representative energy source expected to replace fossil fuels particularly used in internal combustion engines. One of the most important components is polymer electrolyte membranes (PEMs) acting as a proton conducting barrier to prevent fuel gas crossover. Since water channels act as proton pathways through PEMs, many researchers have been focused on the 'good phase-separation of hydrophilic moiety' which ensures high water retention under low humidity enough to keep the water channel for good proton conduction. Here, we summarized the strategies which have been adopted to synthesize sulfonated PEMs having high proton conductivities even under low humidified conditions, and hope this review will be helpful to design high performance hydrocarbon PEMs.

• Journal of Periodontal and Implant Science
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• v.27 no.1
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• pp.19-43
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• 1997

The barrier membranes for GTR procedure could be affected bY bacterial contamination after exposure to oral environment. This study was done to evaluate whether the tetracycline impregnated barrier membranes could inhibit bacterial attachment and penetration into membranes. The resorbable membrane(polylactic and polyglycolide copolymer, $Resolute^{(R)}$, W.L Gore and Associates, Inc..USA) and the non-resorbable membrane(e-PTFE; Gore-TexTM, W.L. Gore & Associates, Inc.,USA) were cut into 4mm discs and trated with 5% tridodecylmethylammonium chloride solution in ethanol and dried in air. The membranes were immersed in tetracycline(TC) solution (100mg/ml, pH 8.0) and dried. To the maxillary canine-premolar region in six periodontally healthy volunteers, removable acrylic devices were inserted, on which 8 cylindrical chambers were glued with TC impregnated and non-impregnated discs, the membrane discs were examined for bacterial attachment and penetration, and structural changes under SEM and LM. From the 1st day to the 7th day, membranes showed bacterial plaque formation composed of cocci and rods. Thereafter, filamentous bacteria appeared and the plaque thickness increased. The TC impregnated e-PTFE membranes showed less bacterial attachment and delayed in bacterial plaque maturation than non-treated membranes. As for bacterial penetration, the TC impregnated e-PTFE membranes showed superficial invasion and infrequent presence of bacteria in unexposed inner surface at the 4th week. while the non-treated e-PTFE membranes showed deep bacterial invasion at the 2nd week and frequent presence of internal bacteria at the 4th week. The resorbable membranes started to be resorbed at the 2nd week and were perforated at the 4th week, regardless of TC treatment. In conclusion, bacterial plaque formation and penetration was efficiently delayed in TC impregnated e-PTFE membranes, whereas resorbable membranes were similar in bacterial invasion due to membrane degradation and perforation, regardless of TC treatment.