359 research outputs found
Patterns of Striped order in the Classical Lattice Coulomb Gas
We obtain via Monte Carlo simulations the low temperature charge
configurations in the lattice Coulomb gas on square lattices for charge filling
ratio in the range . We find a simple regularity in the low
temperature charge configurations which consist of a suitable periodic
combination of a few basic striped patterns characterized by the existence of
partially filled diagonal channels. In general there exist two separate
transitions where the lower temperature transition () corresponds to the
freezing of charges within the partially filled channels. is found to be
sensitively dependent on through the charge number density within the channels.Comment: 4 pages, 8 figure
Refining Historical earthquake Data Through Modeling and Scale Model Tests
This study was performed for the reevaluation of historical earthquake records which occurred in Korea through tests and numerical analyses. For the scale model tests, static and cyclic lateral load tests on wooden frames that constitute a Korean ancient commoner’s house were conducted. Full-scale models of two types of frames were used for testing. Two 1:4 scale models were tested for rock and soil foundation conditions. Scaled real earthquake time histories were inputted for the tests. The peak ground acceleration (PGA) at the collapse of the house at the soil site was 0.25g, whereas PGA for moderate damage at the rock site was 0.6g. The intensity of major historical earthquake records related with house collapses was reevaluated based on the results of these scale mode1 tests. The magnitudes of historical earthquake records related with house collapses were estimated considering the magnitude, epicentral distance, soil condition and aging of the house. Eighteen artificial time histories for magnitudes 6-8, epicentral distances 5 km - 350 km and hard and soft soil condition were generated. The aging effects of the house was modeled as the lateral loading capacity of wooden frames represented by hysteretic stiffness decreased linearly with time
Seroprevalence of Tissue Invading Parasitic Infections Diagnosed by ELISA in Korea
Seroprevalence of the IgG antibodies for Clonorchis sinensis, Paragonimus westermani, Taenia solium metacestode (cysticercus), and Spirometra erinacei plerocercoid (sparganum) was measured using enzyme-linked immunosorbent assay (ELISA) in sera of patients in Korea from 1993 to 2006. A total of 74,448 specimens referred nationwide from 121 hospitals revealed an IgG positive rate of 7.6% for the 4 parasites. The IgG positive rate (18.7%) for the 4 parasites in 1993 decreased gradually to 6.6% in 2006. Individual positive rate decreased from 5.2% (1993) to 1.6% (2006) for C. sinensis, from 2.8% (1993) to 1.1% (2006) for P. westermani, from 8.3% (1993) to 2.2% (2006) for cysticercus, and from 2.6% (1993) to 1.6% (2006) for sparganum. The positive rate was highest (21.2%) in the group of patients who ranged in age from 50-59 yr old, and in the group that was referred from the Seoul area (55.9%). In conclusion, our results suggest that tissue invading parasitic infections should always be included in differential diagnosis for patients with eosinophilia associated lesions of the central nervous system, liver, and lungs in Korea
Chemicals Facilitating Reprogramming: Targeting the SAM Binding Site to Identify Novel Methyltransferase Inhibitors
© 2014 John Wiley & Sons, Ltd. Reprogramming of somatic cells to a pluripotent state has been achieved by viral-mediated transduction of defined transcription factors. In order to achieve the goal of clinical application, it is necessary to overcome a variety of limitations, including poor reprogramming efficiencies and viral integration. One strategy is to identify small-molecule inhibitors that can improve reprogramming efficiency or replace defined transcription factors. Several reports have demonstrated that modulation of chromatin-modifying enzymes can significantly improve reprogramming efficiency. Key enzymes include DNA and histone methyltransferases, which utilize the cofactor S-adenosyl methionine (SAM) to transfer a methyl group. In this chapter, we review our efforts to identify SAM analogues by virtual screening
Long-term Growth of Pediatric Patients Following Living-Donor Liver Transplantation
In order to determine the influence of living donor liver transplantation (LDLT) on long-term growth, we studied the progress of 36 children who had survived more than 5 yr after LDLT from 1994 to 1999. The median age at the transplantation was 1.5 yr (range: 6 months-15 yr) and the median follow-up period was 6.5 yr (range: 5-9 yr). A height standard deviation score (zH) was analyzed for each patient according to medical records. Significant catch-up growth occurred within 2 yr after LDLT with a mean zH changing from -1.2 to 0.0 and was maintained for up to 7 yr post-transplantation (zH-0.1). Younger children (<2 yr) were more growth-retarded at the time of LDLT, but showed higher catch-up growth rates and their final zH was greater than that of older children. Children with liver cirrhosis were more growth-retarded at the time of LDLT, but showed significant catch-up growth and their final height was similar to children with fulminant hepatitis. Growth in children who experienced significant hepatic dysfunction after LDLT was not significantly different from those without graft dysfunction. There was no difference between the types of immunosuppressants used. Our finding suggests that LDLT can result in adequate catch-up linear growth, and this effect can persist even after 7 yr post-transplantation
An endoscope with integrated transparent bioelectronics and theranostic nanoparticles for colon cancer treatment
The gastrointestinal tract is a challenging anatomical target for diagnostic and therapeutic procedures for bleeding, polyps and cancerous growths. Advanced endoscopes that combine imaging and therapies within the gastrointestinal tract provide an advantage over stand-alone diagnostic or therapeutic devices. However, current multimodal endoscopes lack the spatial resolution necessary to detect and treat small cancers and other abnormalities. Here we present a multifunctional endoscope-based interventional system that integrates transparent bioelectronics with theranostic nanoparticles, which are photoactivated within highly localized space near tumours or benign growths. These advanced electronics and nanoparticles collectively enable optical fluorescence-based mapping, electrical impedance and pH sensing, contact/temperature monitoring, radio frequency ablation and localized photo/chemotherapy, as the basis of a closed-loop solution for colon cancer treatment. In vitro, ex vivo and in vivo experiments highlight the utility of this technology for accurate detection, delineation and rapid targeted therapy of colon cancer or precancerous lesions.
Structural Relaxation, Self Diffusion and Kinetic Heterogeneity in the Two Dimensional Lattice Coulomb Gas
We present Monte Carlo simulation results on the equilibrium relaxation
dynamics in the two dimensional lattice Coulomb gas, where finite fraction
of the lattice sites are occupied by positive charges. In the case of high
order rational values of close to the irrational number
( is the golden mean), we find that the system
exhibits, for wide range of temperatures above the first-order transition, a
glassy behavior resembling the primary relaxation of supercooled liquids.
Single particle diffusion and structural relaxation show that there exists a
breakdown of proportionality between the time scale of diffusion and that of
structural relaxation analogous to the violation of the Stokes-Einstein
relation in supercooled liquids. Suitably defined dynamic cooperativity is
calculated to exhibit the characteristic nature of dynamic heterogeneity
present in the system.Comment: 12 pages, 20 figure
Regulation of Proinflammatory Mediators via NF-κB and p38 MAPK-Dependent Mechanisms in RAW 264.7 Macrophages by Polyphenol Components Isolated from Korea Lonicera japonica THUNB
Lonicera japonica THUNB., which abundantly contains polyphenols, has been used as a traditional medicine for thousands of years in East Asian countries because of the anti-inflammation properties. This study aimed to investigate the anti-inflammatory mechanism of polyphenol components isolated from Korea L. japonica T. by nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases (MAPKs) pathway. Polyphenols significantly decreased lipopolysaccharide- (LPS-) induced mRNA and protein expression of inducible nitric oxide synthase and cyclooxygenase-2, as well as mRNA expression of tumor necrosis factor-alpha, interleukin- (IL-) 1β, and IL-6. Moreover, polyphenols inhibited nuclear translocation of NF-κB p65, phosphorylation/degradation of the inhibitor of κB, and phosphorylation of p38 MAPK, whereas the extracellular signal-regulated kinase and Janus N-terminal kinase were not affected. These results indicate that polyphenol components isolated from Korea L. japonica T. should have anti-inflammatory effect on LPS-stimulated RAW 264.7 cells through the decrease of proinflammatory mediators expression by suppressing NF-κB and p38 MAPK activity
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