• Archives of Pharmacal Research
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• v.25 no.2
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• pp.143-150
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• 2002

Fluorescent probes bound to DNA typically display nanosecond decay times and reveal only nanosecond motions. We extend the time range of measurable DNA dynamics using $[Ru(pby)_2(dppz)]^{2+}$ (bpy=2.2'-bipyridine, dppz=dipyrido[3,2-a2',3'-c]phenazine) (RuBD) which displays a mean lifetime near 90 ns. To test the usefulness of RuBD as a probe for diffusive processes in calf thymus DNA, we compared the efficiencies of fluorescence resonance energy transfer (FRET) using three donors which display lifetimes near 5 ns for acridine orange (AO), 22 ns for ethidum bromide (EB) and 92 ns for RuBD, with nile blue (NB) as the acceptor. The F rster distances for AO-NB, EB-NB and RuBD-NB donor-acceptor pairs were 42.3, 52.3, and $30.6{\;}{\AA}$, respectively. All three donors showed dramatic decreases in fluorescence intensities and more rapid intensity decays with increasing NB concentrations. The intensity decays of AO and EB in the presence of varying concentrations of NB were satisfactorily described by the one-dimensional FRET model without diffusion (Blumen and Manz, 1979). In the case of the long-lifetime donor RuBD, the experimental phase and modulation somewhat deviated from the recovered values computed from this model. The recovered NB concentrations and FRET efficiencies from the model were slightly larger than the expected values, however, the recovered and expected values did not show a significant difference. Thus, it is suggested that the lifetime of RuBD is too short to measure diffusive processes in calf thymus DNA.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.630-635
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• 2009

This study was performed to analyze various antioxidants, to evaluate the antioxidative activities, and to measure the protective effect for gap junction intercellular communication (GJIC) to assess the functional potency of the cherry tomato. The ascorbic acid, lycopene, and ${\beta}-carotene$ were measured at $503.4{\pm}9.6$, $39.7{\pm}1.5$, and $7.4{\pm}0.3$ mg/100 g d.w., and ${\alpha}-$, ${\beta}+{\gamma}-$, ${\delta}-tocopherol$ contents were measured at $8.3{\pm}0.1$, $1.7{\pm}0.0$, and $0.1{\pm}0.0$ mg/100 g d.w., respectively. Cherry tomato extract using hexane/acetone/EtOH (2:1:1, CTE) exhibited a ABTS radical scavenging activity with an $IC_{50}$ value of $48.83{\pm}0.30\;{\mu}g/mL$. The cherry tomato protected against the inhibition of GJIC induced by $H_2O_2$ in WB-F344 rat liver epithelial cells, and the reduction in phosphorylated Cx43 was most clearly correlated with the concentration of CTE. These results demonstrated that the cherry tomato harbors a wealth of potent antioxidants and might be protect human body against the inhibition of the GJIC by toxic components.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.1
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• pp.83-94
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• 2016

Performance of absorbent for post-combustion $CO_2$ capture was measured and discussed. Fully saturated fresh absorbent (P2-15F) and absorbents sampled from absorption and regeneration reactor of continuous $CO_2$ capture process, P2-15A, P2-15R, respectively, were used as representative absorbents. Small scale fluidized bed reactor (0.05 m I.D., 0.8 m high) which can measure exhaust gas concentration and weight change simultaneously was used to analyze regeneration characteristics for those absorbents. Exhausted moles of $CO_2$ and $H_2O$ were measured with increasing temperature. $H_2O/CO$ ratio and working capacity were determined and discussed to confirm reason of reactivity decay after continuous operation. Moreover, possibility of side reaction was checked based on the $H_2O/CO_2$ mole ratio. Finally, suitable regeneration temperature range was confirmed based on the trend of working capacity with temperature.

• Journal of Life Science
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• v.16 no.1
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• pp.64-70
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• 2006

Starch gel electrophoresis was used to estimate genetic diversity and population structure of Pyrola fauriena H. Andr. in Korea. The percentage of polymorphic loci within enzymes was $57.1\%$. The values of genetic diversity at the species level and at the population were higher than average values for herbaceous with similar life history traits (Hes : 0.149; Hep = 0.134, respectively), whereas the extent of the population divergence was relatively low $(G_{ST}=0.082)$. $F_{IS}$, a measure of the deviation from random mating within the 12 populations, was 0.298. An indirect estimate of the number of migrants per, generation (Nm = 2.81) indicates that gene flow is moderate among Korean populations of the species. Analysis of fixation indices revealed a substantial heterozygosity deficiency in some populations and at some loci. This indicates that some populations sampled may have been substructured largely due to rhizotamous spread and decrease of population sizes.

• Smart Structures and Systems
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• v.12 no.3_4
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• pp.363-379
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• 2013

Dynamic displacement of structures is an important index for in-service structural condition and behavior assessment, but accurate measurement of structural displacement for large-scale civil structures such as long-span bridges still remains as a challenging task. In this paper, a vision-based dynamic displacement measurement system with the use of digital image processing technology is developed, which is featured by its distinctive characteristics in non-contact, long-distance, and high-precision structural displacement measurement. The hardware of this system is mainly composed of a high-resolution industrial CCD (charge-coupled-device) digital camera and an extended-range zoom lens. Through continuously tracing and identifying a target on the structure, the structural displacement is derived through cross-correlation analysis between the predefined pattern and the captured digital images with the aid of a pattern matching algorithm. To validate the developed system, MTS tests of sinusoidal motions under different vibration frequencies and amplitudes and shaking table tests with different excitations (the El-Centro earthquake wave and a sinusoidal motion) are carried out. Additionally, in-situ verification experiments are performed to measure the mid-span vertical displacement of the suspension Tsing Ma Bridge in the operational condition and the cable-stayed Stonecutters Bridge during loading tests. The obtained results show that the developed system exhibits an excellent capability in real-time measurement of structural displacement and can serve as a good complement to the traditional sensors.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.1
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• pp.63-72
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• 2006

Purpose: The purpose of this study was to compare the accuracy of master cast fabricated by using different impression methods at the different impression levels. Material and Method: The master model used in this study was resin block having low implant analogs. Impression method studied were 1) direct method on future level (Group FIX-D), 2) Indirect method on fixture level(Group FIX-I), 3) Modified indirect method on fixture level(Group FD(-M), 4) Direct method on abutment level(Group AB-D) and 5) Indirect method on abutment level(Group AB-I). Each of the five groups took 10 impressions. Fifty impressions were made for master cast by using Impregum $F^(R)$ impression material loaded on individual tray. Three dimensional measuring microscope was used to measure the inter-implant distance. Error rate of each inter-implant distance were calculated and evaluated. Results: The results were as follows. 1. Group FIX exhibited higher accuracy than group AB. 2 In group FIX, modified indirect method showed the highest accuracy, while indirect method showed the lowest accuracy. In group Ab, indirect method showed the higher accuracy than direct method. 3. Group FIX showed larger horizontal error than group AB. But, group AB showed the larger vertical error than group FIX. 4. Group Fix-M showed smallest vertical and horizontal error.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.1
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• pp.23-29
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• 2016

In this paper, in order to quantify the peristalsis occurrence in a guinea pig's large intestine, a miniaturized air-gap capacitive pressure sensor was fabricated through micro-electro-mechanical system (MEMS). The proposed pressure sensor is a two-layered biocompatible polyimide substrate consisting of an air-gap capacitive plates between the substrates. The proposed pressure sensor was designed with a careful consideration of the structure and motility mechanism of the guinea pig's large intestine. Artificial pellets were mounted on a prototype pressure sensor to provide some redundancies in the form of size and shape of the guinea pig feces. Capacitance of a prototype sensor was recorded to be 2.5 ~ 3 pF. This capacitance value was later converted to count value using a lab fabricated data conversion system. Sensitivity of the pressure sensor was recorded to be below 1 mmHg per atmospheric pressure. During in vivo testing, artificial peristalsis caused by drug injection was measured by inserting the prototype pressure sensor into the guinea pig's large intestine and pressure data obtained due to artificial peristalsis was graphed using a labview program. The proposed pressure sensor could measure the pressure changes in the proximal, medial, and distal parts of the large intestine. The results of the experiment confirmed that pressure changes of guinea pig's large intestine was proportional to the degree of drug injection.

• Journal of Crop Science and Biotechnology
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• v.10 no.2
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• pp.98-105
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• 2007

Phylogenetic relationships in Korean watermelons were evaluated by genetic similarity coefficients using 15 SSR(simple sequence repeat), 14 SCAR(sequence characterized amplified region) and 14 CAPS(sequence characterized amplified region) markers. The SSR markers were selected from previously reported melon and watermelon SSRs through testing polymorphisms within a set of commercial $F_1$ varieties. The SCAR and CAPS markers were developed from polymorphic AFLP(amplified fragment length polymorphism) markers between inbred lines 'BN4001' and 'BN4002'. From the AFLP analysis, 105 polymorphic fragments were identified between the inbred lines using 1,440 primer combinations of EcoRI+CNNN and XbaI+ANNN. Based on the sequencing data of these polymorphic fragments, we synthesized sequence specific primer pairs and detected clear and reliable polymorphisms in 27 primer pairs by indels(insertion/deletion) or RFLP(restriction fragment length polymorphism). A total of 43 sequence-based PCR markers were obtained and polymorphic information content(PIC) was analyzed to measure the informativeness of each marker in watermelon varieties. The average PIC value of SCAR markers was 0.41, which was similar to that of SSR markers. Genetic diversity was also estimated by using these markers to assess the phylogenetic relationships among commercial varieties of watermelon. These markers differentiated 26 Korean watermelon varieties into two major phylogenetic groups, but this grouping was not significantly correlated with their morphological and physiological characteristics. The mean genetic similarity was 66% within the complete set of 26 commercial varieties. In addition, these sequence-based PCR markers were reliable and useful to identify cultivars and genotypes of watermelon.

• Journal of radiological science and technology
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• v.40 no.4
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• pp.621-626
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• 2017

In this paper, an optical dosimetric system for radiation dose measurement is developed and characterized for 100 MeV proton beams in KOMAC(Korea Multi-Purpose Accelerator Complex). The system consists of 10 wt% Ultima GoldTM liquid organic scintillator in the ethanol, a camera lens(50 mm / f1.8), and a high sensitivity CMOS(complementary metal-oxide-semiconductor) camera (ASI120MM, ZWO Co.). The FOV(field of view) of the system is designed to be 150 mm at a distance of 2 m. This system showed sufficient linearity in the range of 1~40 Gy for the 100 MeV proton beams in KOMAC. We also successfully got the percentage depth dose and the isodose curves of the 100 MeV proton beams from the captured images. Because the solvent is not a human tissue equivalent material, we can not directly measure the absorbed dose of the human body. Through this study, we have established the optical dosimetric procedure and propose a new volume dose assessment method.

• Journal of Korean Vacuum Science & Technology
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• v.4 no.3
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• pp.73-77
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• 2000

Single crystal and polycrystalline Si thin films were doped with phosphorus by a 2-zone diffusion method to develop the low-resistivity polycrystalline Si electrode for a hemispherical grain. Solid phosphorus source was used in order to achieve uniformly and highly doped surface region of polycrystalline Si films having rough surface morphology. In case of 2-zone diffusion method, it is proved that the heavy doping near the surface area can be achieved even at a relatively low temperature. SIMS analysis revealed that phosphorus doping concentration in case of using solid P as a doping source was about 50 times as that of phosphine source at 750$^{\circ}C$. Also, ASR analysis revealed that the carrier concentration was about 50 times as that of phosphine. In order to evaluate the electrical characteristics of doped polycrystalline Si films for semiconductor devices, MOS capacitors were fabricated to measure capacitance of polycrystalline Si films. In ${\pm}$2 V measuring condition, Si films, doped with solid source, have 8% higher $C_{min}$ than that of unadditional doped Si films and 3% higher $C_{min}$ than that of Si films doped with $PH_3$ source. The leakage current of these films was a few fA/${\mu}m^2$. As a result, a 2-zone diffusion method is suggested as an effective method to achieve highly doped polycrystalline Si films even at low temperature.