• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.3034-3038
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• 2009

A simple, rapid, practical and sensitive spectofluorimetric method was developed for the determination of trace amount of heparin (Hep). Under the Optimum conditions, we studied the interaction between NFLX-Ce$^{3+}$-Hep complex by using absorption and fluorescence spectra. It was observed that Hep remarkably enhance the fluorescence intensity of the NFLX-Ce$^{3+}$ complex at ${\lambda}$= 356 nm in the buffer solution of pH = 7.60 and the enhancement effect is shown to relate with the concentration of Hep. The linear range and detection limit for the determination of Hep was obtained. By the Rosenthal graphic method, the association constant (K) and binding numbers (N) of Hep with probe were investigated. This method is relatively free of interference from coexisting substances and successfully applied for the determination of heparin in heparin sodium injection samples. A suitable mechanism of fluorescence enhancement between NFLX-Ce$^{3+}$ and the NFLX-Ce$^{3+}$-Hep systems were proposed and discussed.

• Molecules and Cells
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• v.39 no.1
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• pp.46-52
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• 2016

It is increasingly apparent that nature evolved peroxiredoxins not only as $H_2O_2$ scavengers but also as highly sensitive $H_2O_2$ sensors and signal transducers. Here we ask whether the $H_2O_2$ sensing role of Prx can be exploited to develop probes that allow to monitor intracellular $H_2O_2$ levels with unprecedented sensitivity. Indeed, simple gel shift assays visualizing the oxidation of endogenous 2-Cys peroxiredoxins have already been used to detect subtle changes in intracellular $H_2O_2$ concentration. The challenge however is to create a genetically encoded probe that offers real-time measurements of $H_2O_2$ levels in intact cells via the Prx oxidation state. We discuss potential design strategies for Prx-based probes based on either the redoxsensitive fluorophore roGFP or the conformation-sensitive fluorophore cpYFP. Furthermore, we outline the structural and chemical complexities which need to be addressed when using Prx as a sensing moiety for $H_2O_2$ probes. We suggest experimental strategies to investigate the influence of these complexities on probe behavior. In doing so, we hope to stimulate the development of Prx-based probes which may spearhead the further study of cellular $H_2O_2$ homeostasis and Prx signaling.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.11 s.102
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• pp.1164-1170
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• 2005

This paper presents a dual-band, dual-polarized microstrip patch antenna with simple dual-probe feed. The inter-port isolation and cross-polarization are greatly improved by designing feed structure with annular gap between patch and feed-probe. Measured results show that the antenna's inter-port isolation and cross-polarization in each -10 dB return loss bandwidth of $1.84\;GHz\~l.93\;GHz$ and $2.62\;GHz\~2.81\;GHz$ are greater than 21 dB, greater than 22.2 dB and greater than 27 dB, greater than 19 dB, respectively. The antenna gain is about 6.9 dBi in both frequency bands.

• Journal of Astronomy and Space Sciences
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• v.34 no.4
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• pp.343-352
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• 2017

A space plasma facility has been operated with a back-diffusion-type plasma source installed in a mid-sized vacuum chamber with a diameter of ~1.5 m located in Satellite Technology Research Center (SaTReC), Korea Advanced Institute of Science and Technology (KAIST). To generate plasma with a temperature and density similar to the ionospheric plasma, nickel wires coated with carbonate solution were used as filaments that emit thermal electrons, and the accelerated thermal electrons emitted from the heated wires collide with the neutral gas to form plasma inside the chamber. By using a disk-type Langmuir probe installed inside the vacuum chamber, the generation of plasma similar to the space environment was validated. The characteristics of the plasma according to the grid and plate anode voltages were investigated. The grid voltage of the plasma source is realized as a suitable parameter for manipulating the electron density, while the plate voltage is suitable for adjusting the electron temperature. A simple physical model based on the collision cross-section of electron impact on nitrogen molecule was established to explain the plasma generation mechanism.

• Transactions of the Society of Information Storage Systems
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• v.2 no.2
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• pp.96-99
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• 2006

In this research, a wafer-level transfer method of cantilever away on a conventional CMOS circuit has been developed for high density probe-based data storage. The transferred cantilevers were silicon nitride ($Si_3N_4$) cantilevers integrated with poly silicon heaters and piezoelectric sensors, called thermo-piezoelectric $Si_3N_4$ cantilevers. In this process, we did not use a SOI wafer but a conventional p-type wafer for the fabrication of the thermo-piezoelectric $Si_3N_4$ cantilever arrays. Furthermore, we have developed a very simple transfer process, requiring only one step of cantilever transfer process for the integration of the CMOS wafer and cantilevers. Using this process, we have fabricated a single thermo-piezoelectric $Si_3N_4$ cantilever, and recorded 65nm data bits on a PMMA film and confirmed a charge signal at 5nm of cantilever deflection. And we have successfully applied this method to transfer 34 by 34 thermo-piezoelectric $Si_3N_4$ cantilever arrays on a CMOS wafer. We obtained reading signals from one of the cantilevers.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.7
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• pp.529-537
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• 2021

Wind tunnel tests were carried out with a scramjet high speed vehicle. Since the scramjet engine does not have a compressor, it has a simple structure, but it is important to design the intake for the supersonic combustion in the combustion chamber. In this study, internal flow characteristics and the starting condition were analyzed by measuring the pressure at the isolator exit just before the combustion chamber, and the intake performance parameters were calculated and compared the result on every Mach number. The aerodynamic characteristics of the flow-through high speed vehicle were analyzed and internal drag correction is required to precisely analyze the aerodynamic characteristics. In this paper, an experimental technique using three probes for internal drag correction was proposed. By applying internal drag correction, it was able to figure out the effect of the internal flow on the aerodynamic force of the vehicle.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.5
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• pp.1300-1307
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• 1995

The effect of thermal stratification on the turbulent dispersion from a fine cylindrical heat source was experimentally examined in a wind tunnel with and without a strong temperature gradient. A 0.5 mm dia. nichrome wire was used as a line heat source. Turbulent intensities, r.m.s. value of temperature and convective heat fluxes were measured by using a hot-wire and cold-wire combination probe. The results show that the peack value and the spread of the vertical turbulent intensity for the stratified case are far lower than those in the neutral case, which indicates that the stable temperature gradient suppresses the vertical velocity component. All of the third order moments including heat fluxes measured in the stable condition have very small values than those of the neutral case. This nature suggests that the decrease of scalar fluctuations in the stably stratified flow is mainly due to the suppression ofthe turbulent diffusion processes by the stable stratification. A simple gradient model with a composite timescale which has a simple weighted algebraic mean between dynamic and thermal time scale yields reasonably good numerical values in comparison with the experimental data.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.3998-4002
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• 2012

With continuing progress of nanotechnologies and various applications of nanoparticles, one needs to develop a quick and fairly standard assessment tool to evaluate cytotoxicity of nanoparticles. However, much cytotoxicity studies on the interpretation of the interaction between nanoparticles and cells are non-mechanistic and time-consuming. Here, we propose a simple screening method for the analysis of the interaction between several AgNPs (5.3 to 64 nm) and fluorescence-dye containing vesicles ($12{\mu}m$) acting as a biomimetic cell-membrane. Fluorescence-dye containing vesicle was prepared using a fluorescence probe (1,6-diphenyl-1,3,5-hexatryene), which was intercalated into the lipid bilayer due to their hydrophobicity. Zeta potential of all materials except for bare-AgNPs (+32.8 mV) was negative (-26 to -54 mV). The morphological change (i.e., rupture and fusion of vesicle, and release of dye) after mixing of the vesicle and AgNPs was observed by fluorescence microscopy, and fluorescence image were different with coating materials and surface charge of x-AgNPs. In the results, we found that the surface charge of nanoparticles is the key factor for vesicle rupture and fusion. This proposed method might be useful for analyzing the cytotoxicity of nanoparticles with cell-membranes instead of in vitro or in vivo cytotoxicity tests.

• Clinics in Shoulder and Elbow
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• v.22 no.3
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• pp.146-148
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• 2019

We report a simple technique for repairing capsular tear, using only a hook-like, cannulated instrument and braided sutures without relaying steps. A No. 2 braided suture is passed through the lumen of the instrument. Under direct arthroscopic view, the tip of the instrument is passed through the side of the capsule that has previously been separated with the probe. One end of the suture is retrieved with a grasper through a separate portal. The tip is moved back without withdrawing through the skin, and reinserted into the other side of the capsule. Holding the end retrieved earlier, the other end of the suture is retrieved with a suture retriever. After complete removal of the instrument, the suture is tied through a cannula using the standard knot tying techniques. The same procedures are repeated for other required knots.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.1-4
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• 1999

Beijing White Chickens laying larger eggs and smaller eggs were respectively used as parental individuals for mating to produce the F1 progeny and then the F1 progeny individuals mated to produce 125 individuals of the F2 progeny. Three bands associated with the egg weight performance were identified from DNA fingerprints of the 125 individuals generated with a bovine minisatellite probe BM6.5B. The simple linear correlation analysis showed that the coefficients of correlation between frequencies of the three bands (DB1, DB2 and DB3) and egg weights were -0.6, -0.6 and 0.9, respectively.