475 research outputs found
Income Distribution and Public Transfers as Social Safety Nets in Korea
Using 5-year balanced household panel data, this paper shows that the inequality of per capita income in Korea aggravated during the financial crisis in 1998. The decomposition analysis of income inequality by factor component shows that the dominant positive effect on the income inequality is by the asset income. Next is the wage income, followed by the other income. Furthermore, this paper shows that social safety net programs were not yet in place during the initial period of the crisis. Public transfers were not effective social safety net devices and did not contribute in decreasing income inequality. Private transfers, on the other hand, were effective devices and narrowed the disparity in household income.
Temperature-dependent evolutions of excitonic superfluid plasma frequency in a srong excitonic insulator candidate, TaNiSe
We investigate an interesting anisotropic van der Waals material,
TaNiSe, using optical spectroscopy. TaNiSe has been
known as one of the few excitonic insulators proposed over 50 years ago.
TaNiSe has quasi-one dimensional chains along the -axis. We have
obtained anisotropic optical properties of a single crystal TaNiSe
along the - and -axes. The measured - and -axis optical
conductivities exhibit large anisotropic electronic and phononic properties.
With regard to the -axis optical conductivity, a sharp peak near 3050
cm at 9 K, with a well-defined optical gap ( 1800
cm) and a strong temperature-dependence, is observed. With an increase
in temperature, this peak broadens and the optical energy gap closes around
325 K(). The spectral weight redistribution with respect to the
frequency and temperature indicates that the normalized optical energy gap
() is . The
temperature-dependent superfluid plasma frequency of the excitonic condensation
in TaNiSe has been determined from measured optical data. Our
findings may be useful for future research on excitonic insulators.Comment: 17 pages, 5 figure
Study on fatigue experiment for transverse butt weldsunder 2G and 3G weld positions
ABSTRACTAlthough the transverse butt weld method with ceramic backing strip has been widely used in various industrial fields for its fabricational convenience, it is rarely used in offshore industries since the fatigue strength of the weld joint has not been proved sufficiently. This study conducted fatigue tests for series of butt weld specimens with horizontal (2G) and vertical (3G) welding positions in order to verify the fatigue strength compared to S-N curve by DNV (Det Norske Veritas), IIW (International Institute of Welding) and Eurocode 3. The difference of the 2G specimens and the 3G specimens are investigated in terms of angular distortion and the effect on the fatigue strength are analyzed
Structural studies on Helicobacter pylori ATP-dependent protease, FtsH
The crystal structures of the Helicobacter pylori FtsH ATPase domain in the nucleotide-free state and complexed with ADP have been determined
DHP-Derivative and Low Oxygen Tension Effectively Induces Human Adipose Stromal Cell Reprogramming
BACKGROUND AND METHODS: In this study, we utilized a combination of low oxygen tension and a novel anti-oxidant, 4-(3,4-dihydroxy-phenyl)-derivative (DHP-d) to directly induce adipose tissue stromal cells (ATSC) to de-differentiate into more primitive stem cells. De-differentiated ATSCs was overexpress stemness genes, Rex-1, Oct-4, Sox-2, and Nanog. Additionally, demethylation of the regulatory regions of Rex-1, stemnesses, and HIF1alpha and scavenging of reactive oxygen species were finally resulted in an improved stem cell behavior of de-differentiate ATSC (de-ATSC). Proliferation activity of ATSCs after dedifferentiation was induced by REX1, Oct4, and JAK/STAT3 directly or indirectly. De-ATSCs showed increased migration activity that mediated by P38/JUNK and ERK phosphorylation. Moreover, regenerative efficacy of de-ATSC engrafted spinal cord-injured rats and chemical-induced diabetes animals were significantly restored their functions. CONCLUSIONS/SIGNIFICANCE: Our stem cell remodeling system may provide a good model which would provide insight into the molecular mechanisms underlying ATSC proliferation and transdifferentiation. Also, these multipotent stem cells can be harvested may provide us with a valuable reservoir of primitive and autologous stem cells for use in a broad spectrum of regenerative cell-based disease therapy
Valley-Polarized Interlayer Conduction of Anisotropic Dirac Fermions in SrMnBi2
We report the valley-selective interlayer conduction of SrMnBi2 under in-plane magnetic fields. The c-axis resistivity of SrMnBi2 shows clear angular magnetoresistance oscillations indicating coherent interlayer conduction. Strong fourfold variation of the coherent peak in the c-axis resistivity reveals that the contribution of each Dirac valley is significantly modulated by the in-plane field orientation. This originates from anisotropic Dirac Fermi surfaces with strong disparity in the momentum-dependent interlayer coupling. Furthermore, we found a signature of broken valley symmetry at high magnetic fields. These findings demonstrate that a quasi-two-dimensional anisotropic Dirac system can host a valley-polarized interlayer current through magnetic valley control. © 2014 American Physical Society.open1
Intraoperative acute brain swelling when performing indirect anastomosis in a patient with moyamoya disease -A case report-
A 6-year-old male patient who was suffering from a cold and a transient ischemic attack was scheduled to undergo encephalo-duro-arterio-synangiosis for treating his moyamoya disease. Acute brain edema occurred just after opening the dura mater. Head elevation, reduction of the head rotation and hyperventilation were done. The inhalational agents were discontinued and total intravenous anesthesia was started. The swelling was reduced after intravenously infusing mannitol. An abrupt return from hypocapnia to normocapnea during the induction of general anesthesia was thought to be the cause of the acute brain swelling. In conclusion, correction of hypocapnea needs to be performed gradually during the induction of anesthesia and when performing an operation for treating a patient with moyamoya disease
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