• Journal of Radiation Protection and Research
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• v.22 no.2
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• pp.85-95
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• 1997

TLD and film badges have been traditionally used as formal dosimeters in personal monitoring and are still most widely used. Recently, electronic personal dosimeters based upon Si diode or miniature G-M tube were developed and are getting attractions due to their merits of active nature ; indication of dose rates and the commutative dose, and facilitation of record keeping and radiological control. Response characteristics of the electronic dosimeters including reproducibility, accuracy, linearity, energy and angular dependencies, detection threshold, and response time were examined for three commercial types ; EPD2, STEPHEN6000, and PD-3i. The results were compared with the relevant requirements of IEC standards and Ontario Hydro standards to conclude that their general performances were good. Some specific deficiencies, e.g. incapability of shallow dose measurement of STEPHEN6000, and PD-3i, however, should be corrected to be used as a formal dosimeter.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.4
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• pp.160-165
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• 2001

The effects of various metals on Field Aided Lateral Crystallization (FALC) behaviors of amorphous silicon (a-Si) were investigated. Under an influence of electric field, metals such s Cu, Ni and Co were found to fasten the lateral crystallization toward a metal-free region, exhibiting a typical FALC behavior while the lateral crystallization of a-Si was not obvious for Pd. However, Au, Al and Cr did not induce the lateral crystallization of a-Si in metal-free region. Such phenomenological differences in various metals were studied in terms of dominant diffusing species (DDS) in the reaction between metal and Si. It was judged that the applied electric field enhanced the crystallization velocity by accelerating the diffusion of metal atoms since the occurrence of lateral crystallization would be strongly dependent on the diffusion of metal atoms than that of Si atoms. Therefore, it was concluded that he only metal-dominant diffusing species in the reaction between metal and Si results in the crystallization of a-Si in metal-free region.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.10-10
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• 2008

Silicide is inevitable for CMOSFETs to reduce RC delay by reducing the sheet resistance of gate and source/drain regions. Ni-silicide is a promising material which can be used for the 65nm CMOS technologies. Ni-silicide was proposed in order to make up for the weak points of Co-silicide and Ti-silicide, such as the high consumption of silicon and the line width limitation. Low resistivity NiSi can be formed at low temperature ($\sim500^{\circ}C$) with only one-step heat treat. Ni silicide also has less dependence of sheet resistance on line width and less consumption of silicon because of low resistivity NiSi phase. However, the low thermal stability of the Ni-silicide is a major problem for the post process implementation, such as metalization or ILD(inter layer dielectric) process, that is, it is crucial to prevent both the agglomeration of mono-silicide and its transformation into $NiSi_2$. To solve the thermal immune problem of Ni-silicide, various studies, such as capping layer and inter layer, have been worked. In this paper, the Ni-silicide utilizing Pd stacked layer (Pd/Ni/TiN) was studied for highly thermal immune nano-scale CMOSFETs technology. The proposed structure was compared with NiITiN structure and showed much better thermal stability than Ni/TiN.

• The Korean Journal of Pain
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• v.33 no.4
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• pp.318-325
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• 2020

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a major side effect of anti-cancer drugs. Neurotensin receptors (NTSRs) are widely distributed within the pain circuits in the central nervous system. The purpose of this study was to determine the role of NTSR1 by examining the effects of an NTSR1 agonist in rats with CIPN and investigate the contribution of spinal serotonin receptors to the antinociceptive effect. Methods: Sprague-Dawley rats (weight 150-180 g) were used in this study. CIPN was induced by injecting cisplatin (2 mg/kg) once a day for 4 days. Intrathecal catheters were placed into the subarachnoid space of the CIPN rats. The antiallodynic effects of intrathecally or intraperitoneally administered PD 149163, an NTSR1 agonist, were evaluated. Furthermore, the levels of serotonin in the spinal cord were measured by high-performance liquid chromatography. Results: Intrathecal or intraperitoneal PD 149163 increased the paw withdrawal threshold in CIPN rats. Intrathecal administration of the NTSR1 antagonist SR 48692 suppressed the antinociceptive effect of PD 149163 given via the intrathecal route, but not the antinociceptive effect of intraperitoneally administered PD 149163. Intrathecal administration of dihydroergocristine, a serotonin receptor antagonist, suppressed the antinociceptive effect of intrathecally administered, but not intraperitoneally administered, PD 149163. Injecting cisplatin diminished the serotonin level in the spinal cord, but intrathecal or intraperitoneal administration of PD 149163 did not affect this reduction. Conclusions: NTSR1 played a critical role in modulating CIPN-related pain. Therefore, NTSR1 agonists may be useful therapeutic agents to treat CIPN. In addition, spinal serotonin receptors may be indirectly involved in the effect of NTSR1 agonist.

• Journal of the Korean institute of surface engineering
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• v.49 no.6
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• pp.530-538
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• 2016

There is a close relationship between the performance and the heat generation of the electronic device. Heat generation causes a significant degradation of the durability and/or efficiency of the device. It is necessary to have an effective method to release the generated heat. Based on demands of the printed circuit board (PCB) manufacturing, it is necessary to develop a robust and reliable plating technique for substrates with high thermal conductivity, such as alumina ($Al_2O_3$), aluminium nitride (AlN), and silicon nitride ($Si_3N_4$). In this study, the plating of metal layers on an insulating silicon nitride ($Si_3N_4$) ceramic substrate was developed. We formed a Pd-$TiO_2$ adhesion layer and used APTES(3-Aminopropyltriethoxysilane) to form OH groups on the surface and adhere the metal layer on the insulating $Si_3N_4$ substrate. We used an electroless Ni plating without sensitization/activation process, as Pd particles were nucleated on the $TiO_2$ layer. The electrical resistivity of Ni and Cu layers is $7.27{\times}10^{-5}$ and $1.32{\times}10^{-6}ohm-cm$ by 4 point prober, respectively. The adhesion strength is 2.506 N by scratch test.

• Applied Microscopy
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• v.34 no.2
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• pp.95-102
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• 2004

The TEM samples prepared by ion milling have the advantage that thin area can be obtained from almost any materials. However, it has the disadvantage that the amount of thin area can often be quite limited. For the cross-sectioned samples and grossly heterogeneous materials, the thickness of less than $0.1{\mu}m$ can be achieved by mechanical grinding and polishing (tripod polisher) and then the TEM samples may be ion-milled for final thinning or cleaning. These approaches were described in this paper. Examples of TEM observations were taken from cross-section samples of thin films on silicon and sapphire, from diffusion layers between $Mo_5Si_3\;and\;Mo_2B$, and from rapidly solidified 304 stainless steel powders embedded in electroplated copper.

• Applied Science and Convergence Technology
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• v.27 no.5
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• pp.95-99
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• 2018

We discuss the structural and optical characteristics of GaN nanowires (NWs) grown on Si(111) substrates by a plasma-assisted molecular-beam epitaxy. The GaN NWs with high crystal quality were formed by adopting a new growth approach, so called Ga pre-deposition (GaPD) method. In the GaPD, only Ga was supplied without nitrogen flux on a SiN/Si surface, resulting in the formation of Ga droplets. The Ga droplets were used as initial nucleation sites for the growth of GaN NWs. The GaN NWs with the average heights of 60.10 to 214.62 nm obtained by increasing growth time. The hexagonal-shaped top surfaces and facets were observed from the field-emission electron microscope images of GaN NWs, indicating that the NWs have the wurtzite (WZ) crystal structure. Strong peaks of GaN (0002) corresponding to WZ structures were also observed from double crystal x-ray diffraction rocking curves of the NW samples. At room temperature, free-exciton emissions were observed from GaN NWs with narrow linewidth broadenings, indicating to the formation of high-quality NWs.

• Biomedical Science Letters
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• v.30 no.2
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• pp.37-48
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• 2024

Liposomes are one of the most actively studied and promising drug delivery systems for the treatment of various diseases. In this study, an aptamer-conjugated liposome called "aptamosome" was used, in which an anti-PD-L1 aptamer targeting cancer cells was conjugated to the liposome. These aptamosomes showed remarkable cellular uptake and efficient delivery to Lewis lung carcinoma 2 (LL/2) cancer cells. In addition, suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor (HDACi), was delivered through this aptamer to induce a strong anticancer immunotherapeutic effect. The results of this study showed that when LL/2 cells were treated with SAHA-entrapped aptamosome [SAHA] and liposome [SAHA] and free SAHA, aptamosome [SAHA] improved cell death compared with that of liposomes [SAHA] or free SAHA, and it has demonstrated anticancer efficacy. Moreover, aptamosome [SAHA] induce the secretion of chemokines that promote the migration of activated T cells into tumor tissues. Finally, in vivo experiments showed that aptamosome [SAHA] significantly inhibited the growth rate of LL/2 tumors. Therefore, liposomes combined with an anti-PD-L1 aptamer for efficient SAHA delivery are suggested as an excellent model for drug delivery systems suitable for targeting cancer cells.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.12
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• pp.809-813
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• 2016

We investigated a SiC-based hydrogen gas sensor with MIS (metal-insulator-semiconductor) structure for high temperature applications. The sensor was fabricated by $Pd/TiO_2/SiC$ structure, and a thin titanium dioxide ($TiO_2$) layer was exploited for sensitivity improvement. In the experiment, dependences of I-V characteristics and capacitance response properties on hydrogen gas concentrations from 0 to 2,000 ppm were analyzed at room temperature to $400^{\circ}C$. As the result, our sensor using $TiO_2$ dielectric layer showed possibilities with regard to use in hydrogen gas sensors for high-temperature applications.

• The Korea Journal of Herbology
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• v.35 no.6
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• pp.55-68
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• 2020

Objectives : We observed the possibilities that blue honeysuckle has favorable analgesic or refinement effects on the Primary dysmenorrhea (PD) in rats. Methods : Estradiol benzoate and oxytocin were used to induce the PD rat model. And Blue honeysuckle concentration lyophilized powders (BH) 500, 250 and 125 mg/kg and 500 mg/kg of Lonicerae Flos aqueous extract lyophilized powders (LF) were orally administered, once a day for 10 days at 30 min after each estradiol benzoate treatment. Then the changes on the body weights and gains during experimental periods, abdominal writhing response for analgesic activities, uterine weights, uterus lipid peroxidation, antioxidant defense system - glutathione contents, superoxide dismutase and catalase activities, NF-κB and COX-2 mRNA expressions were monitored with uterus histopathology including immunohistochemistry for tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS).. Results : Inflammatory and oxidative stress mediated PD signs were favorably and dose-dependently inhibited by 10 days continuous oral administration of three different dosages of BH - 500, 250 and 125 mg/kg as comparable to those of indomethacin(IND) 5 mg/kg treated rats in BH 500 mg/kg administered PD rats, and similar to those of LF 500 mg/kg in BH 125 mg/kg, at least in a condition of the present PD rat model. Conclusions : The results suggest that BH has favorable analgesic and refinement activities on the estradiol benzoate and oxytocin treatment-induced PD signs through anti-inflammatory and antioxidative potentials.