• Molecules and Cells
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• v.20 no.2
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• pp.303-303
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• 2005

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.593-594
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• 2006

• JSTS:Journal of Semiconductor Technology and Science
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• v.9 no.1
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• pp.61-66
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• 2009

We have investigated the noise sensitivity of low noise amplifier (LNA) at different frequency. This noise sensitivity analysis provides insights about noise parameters and it is very beneficial for making appropriate design trade-offs. From this work, the circuit designer can choose the adequate noise parameters tolerances.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.496-498
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• 2009

• Proceedings of the Korean Magnestics Society Conference
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• 2016.05a
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• pp.188-189
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• 2016

• Proceedings of the Korean Magnestics Society Conference
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• 2016.05a
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• pp.163-164
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• 2016

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.241.3-242
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• 2003

A simple, specific and sensitive method for the determination of methyltestosterone (MT) in human serum has been developed by gas chromatography/mass spectrometry with the purpose of conducting pharmacokinetic and bioequivalence studies of MT. This method involves the use of liquid-liquid extraction with diethyl ether and derivatization with MSTFA, using 1 ml of serum obtained from volunteers orally taken 50 mg MT. MT showed good resolutions in this conditions and no significant interfering peaks were observed. (omitted)

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.141-141
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• 2000

In situ surface magneto-optic Kerr effect(SMOKE), X-ray photoelectron spectroscopy(XPS) and low energy electron diffraction(LEED) were used to study magnetic and structural properties of ultrathin Fe films grown on the Pd(111) surface. The SMOKE measurement showed strong enhancement of ferromagnetism after proper annealing process. Simultaneous changes in morphology was checked by LEED and XPS. After room temperature Fe deposition. longitudinal magnetization appeared above a critical thickness between 2.0 and 2.5 monolayers. When annealed at 450K, 2.0 monolayer Fe film exhibited boty longitudinal and polar magnetizations while 3.0 and 5.5 monolayer films showed little changes. After annealing at 600K, both magnetizations were totally destroyed in 2.0 monolayer film, but longitudinal magnetization was enhanced in 3.0 monolayer film. In the case of 5.5 monolayer film, it was only after 660K annealing that the enhancement of the longitudinal magnetization was observed. It was concluded that the surface flatness and the amount of intermixing were critical in the development of surface magnetism of this system.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.34.1-34.1
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• 2020

The recent discovery of diffuse dwarf galaxies that are deficient in dark matter appears to challenge the current paradigm of structure formation in our Universe. We describe the numerical experiments to determine if the so-called dark matter deficient galaxies (DMDGs) could be produced when two gas-rich, dwarf-sized galaxies collide with a high relative velocity of ~ 300km/s. Using idealized high-resolution simulations with both mesh-based and particle-based gravito-hydrodynamics codes, we find that DMDGs can form as high-velocity galaxy collisions separate dark matter from the warm disk gas which subsequently is compressed by shock and tidal interaction to form stars. Then using a large simulated universe ILLUSTRISTNG, we discover a number of high-velocity galaxy collision events in which DMDGs are expected to form. However, we did not find evidence that these types of collisions actually produced DMDGs in the ILLUSTRISTNG100-1 run. We argue that the resolution of the numerical experiment is critical to realize the "collision-induced" DMDG formation scenario. Our results demonstrate one of many routes in which galaxies could form with unconventional dark matter fractions.

• International Journal of Stem Cells
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• v.15 no.1
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• pp.85-94
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• 2022

Background and Objectives: Brain organoids have the potential to improve our understanding of brain development and neurological disease. Despite the importance of brain organoids, the effect of vascularization on brain organoids is largely unknown. The objective of this study is to develop vascularized organoids by assembling vascular spheroids with cerebral organoids. Methods and Results: In this study, vascularized spheroids were generated from non-adherent microwell culture system of human umbilical vein endothelial cells, human dermal fibroblasts and human umbilical cord blood derived mesenchymal stem cells. These vascular spheroids were used for fusion with iPSCs induced cerebral organoids. Immunostaining studies of vascularized organoids demonstrated well organized vascular structures and reduced apoptosis. We showed that the vascularization in cerebral organoids up-regulated the Wnt/β-catenin signaling. Conclusions: We developed vascularized cerebral organoids through assembly of brain organoids with vascular spheroids. This method could not only provide a model to study human cortical development but also represent an opportunity to explore neurological disease.