4,168 research outputs found
Mott transition with Holographic Spectral function
We show that the Mott transition can be realized in a holographic model of a
fermion with bulk mass, , and a dipole interaction of coupling strength .
The phase diagram contains gapless, pseudo-gap and gapped phases and the first
one can be further divided into four sub-classes. We compare the spectral
densities of our holographic model with the Dynamical Mean Field Theory (DMFT)
results for Hubbard model as well as the experimental data of Vanadium Oxide
materials. Interestingly, single-site and cluster DMFT results of Hubbard model
share some similarities with the holographic model of different parameters,
although the spectral functions are quite different due to the asymmetry in the
holography part. The theory can fit the X-ray absorption spectrum (XAS) data
quite well, but once the theory parameters are fixed with the former it can fit
the photoelectric emission spectrum (PES) data only if we symmetrize the
spectral function.Comment: 22 pages, 21 figures, v2 symmetrization arguments are abandoned, the
argument of Mott transition is still valid, but comparison with Hubbard model
is modified. Title is change
The Creation Science Movement in Korea: A Perspective from the History and Philosophy of Science
In the seventeenth century, science and religion clashed over cosmology. The relationship between science and religion was at extreme odds at the Galileo trials but softened in the twentieth century when the Catholic Church accepted the new science. Meanwhile, the evolutionary theory proposed in the nineteenth century lowered the status of humans to animals and damaged faith in biblical inspiration. The Scopes Trial in the southern United States in the 1920s was the result of the defiance of the Protestants, who insisted on a literal interpretation of the Bible. "Creation science," which began to thrive in the western United States in the 1960s, insisted on equal time in schools alongside evolutionary theory. After re-peated defeat in court, creation science is desperately trying to get its footing in science with a new name: intelligent design. The creation science movement that came Korea in the 1980s joined hands with Christian obscurantism and is running amok. When creationism pretends to be science, it is an unfair interference of religion in science. Creation science is a pseudoscience that cannot be accepted as science
Atheromatous Embolization during Angiography(A Case Report)
Cholesterol embolization is one of the serious complications of ulcerative
atheromatous plaque. Ischemic changes in the lower extremity, brain and other organs
including the kidney, pancreas and gastrointestinal tract due to atherosclerotic
microemboli have been well documented in autopsy cases in the western world. However,
it has been seldom reported in the Korean literature. We report a case of cholesterol
embolization of a foot that happened during coronary angiography with resultant
gangrene necessitating amputation.
A 60-year-old man visited hospital for the evaluation of angina pectoris. He felt a
sudden severe abdominal pain during the coronary angiography followed by loss of pulsation
of the dorsalis pedis arteries. Acute renal failure, glucose intolerance and
gangrene in both feet developed almost simultaneously, and Syme operation was done.
Dissection of the dorsalis pedis artery demonstrated segmental occlusion by cholesterol
emboli with various stages of organization
Reduced Expression of nm23 Protein is Related to Nodal Metastasis of Human Gastric Carcinoma
Reduced expression of nm23 gene or protein has been known to be
related with nodal metastasis in a variety of malignant tumors of the breast. lung.
liver, prostate. ovary and stomach. To elucidate a possible prognostic factor. we
studied 42 cases of gastric adenocarcinomas for the expression of nm23 protein
using immunohistochemical methods and compared with the known prognostic
parameters. The nm23 protein was intensely stained in the cytoplasm and/or the
nucleus of carcinoma cells in 9 cases(21.4%). The nm23 protein expression of the
non-metastatic group(46.7%) was higher than that of the nodal metastasis group(7.
4%). Perigastric lymph node rnetastasesipttl.Otrl) were more frequently found in the
nrn23 protein neqative group(75.8%) than in the nm23 positive group(22.2%). There
was no significant correlation between nrn23 protein expression and other parameters
such as patient age. sex. WHO grade. Lauren classification. depth of
invasion. location of tumor and size. The results suggest that nm23 protein expression
plays a role in suppression of nodal metastasis in the gastric adenocarcinoma
Vertically integrated visible and near-infrared metasurfaces enabling an ultra-broadband and highly angle-resolved anomalous reflection
An optical device with minimized dimensions, which is capable of efficiently resolving an ultra-broad spectrum into a wide splitting angle but incurring no spectrum overlap, is of importance in advancing the development of spectroscopy. Unfortunately, this challenging task cannot be easily addressed through conventional geometrical or diffractive optical elements. Herein, we propose and demonstrate vertically integrated visible and near-infrared metasurfaces which render an ultra-broadband and highly angle-resolved anomalous reflection. The proposed metasurface capitalizes on a supercell that comprises two vertically concatenated trapezoid-shaped aluminum antennae, which are paired with a metallic ground plane via a dielectric layer. Under normal incidence, reflected light within a spectral bandwidth of 1000 nm ranging from = 456 nm to 1456 nm is efficiently angle-resolved to a single diffraction order with no spectrum overlap via the anomalous reflection, exhibiting an average reflection efficiency over 70% and a substantial angular splitting of 58 degrees. In light of a supercell pitch of 1500 nm, to the best of our knowledge, the micron-scale bandwidth is the largest ever reported. It is noted that the substantially wide bandwidth has been accomplished by taking advantage of spectral selective vertical coupling effects between antennae and ground plane. In the visible regime, the upper antenna primarily renders an anomalous reflection by cooperating with the lower antenna, which in turn cooperates with the ground plane and produces phase variations leading to an anomalous reflection in the near-infrared regime. Misalignments between the two antennae have been particularly inspected to not adversely affect the anomalous reflection, thus guaranteeing enhanced structural tolerance of the proposed metasurface.This work was supported by the National Research Foundation
of Korea (NRF) grants funded by the Korean government
(MSIP) (No. 2016R1A2B2010170 and 2011-0030079) and by a
Research Grant of Kwangwoon University in 2018. The work
was partly supported by the Australian Research Council
Future Fellowship (FT110100853, Dr Duk-Yong Choi), and was
performed in part at the ACT node of the Australian National
Fabrication Facility. The authors thank Prof. L. Shi, Prof. J. Zi
and Y. Zhang from Fudan University and Dr H. Yin from
Ideaoptics Inc., for their help with the Fourier-transformbased angle-resolved spectroscopy (FT-ARS) measurements
Congenital Cystic Adenomatoid Malformation and Extralobar Pulmonary Sequestration in an Infant
Although congenital cystic adenomatoid malformation(CCAM) and
extralobar pulmonary sequestration(EPS) are different entities, they sometimes share
common morphologic features, raising a possibility of a morphogenetic link. We report
an autopsy case of a neonate who had features of both EPS and CCAM. An abnormal
left lung with three separate lobes was found in the left thoracic cavity after removal of
herniated abdominal viscera through the Bochdalek foramen. Two lobes without bronchial
connections were directly connected with the descending aorta, and showed typical
histologic features of CCAM. The lung tissue with normal bronchial connection and
'pulmonary artery supply showed identical features to these accessory lobes. Our case
provides an evidence that CCAM and EPS can occur in a single individual and in the
same side of the lung, and therefore raises a possibility that these two lesions could be
different expressions of the same disease
Observation of enhanced superconductivity in the vicinity of Ar-induced nano-cavities in Pb(111)
Local variations of superconductivity have been studied using scanning tunneling microscopy around nano-cavities formed by Ar ions embedded in Pb(111). Various factors including the density of states at Fermi energy, electron-phonon couplings, and quantum well states, which are known to affect superconductivity, have been examined. We show that the superconductivity is enhanced near the nano-cavities and propose that quantum effects such as quantum confinement, proximity effect and multi-gap effect are possibly involved in determining the superconducting gap of this system. These results have important implications for the characterization and understanding of superconductivity at a nanometer scale. © 2017 The Author(s).1
A Multiwell-Based Detection Platform with Integrated PDMS Concentrators for Rapid Multiplexed Enzymatic Assays
We report an integrated system for accelerating assays with concentrators in a standard 12-well plate (ISAAC-12) and demonstrate its versatility for rapid detection of matrix metalloproteinase (MMP)-9 expression in the cell culture supernatant of breast cancer cell line MDA-MB-231 by accelerating the enzymatic reaction and end-point signal intensity via electrokinetic preconcentration. Using direct printing of a conductive ion-permselective polymer on a polydimethylsiloxane (PDMS) channel, the new microfluidic concentrator chip can be built without modifying the underlying substrate. Through this decoupling fabrication strategy, our microfluidic concentrator chip can easily be integrated with a standard multiwell plate, the de facto laboratory standard platform for high-throughput assays, simply by reversible bonding on the bottom of each well. It increases the reaction rate of enzymatic assays by concentrating the enzyme and the reaction product inside each well simultaneously for rapid multiplexed detection.publishersversionpublishe
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