Total Reflection and Negative Refraction of Dipole-Exchange Spin Waves at Magnetic Interfaces: Micromagnetic Modeling Study

We demonstrated that dipole-exchange spin waves traveling in geometrically restricted magnetic thin films satisfy the same laws of reflection and refraction as light waves. Moreover, we found for the first time novel wave behaviors of dipole-exchange spin waves such as total reflection and negative refraction. The total reflection in laterally inhomogeneous thin films composed of two different magnetic materials is associated with the forbidden modes of refracted dipole-exchange spin waves. The negative refraction occurs at a 90 degree domain-wall magnetic interface that is introduced by a cubic magnetic anisotropy in the media, through the anisotropic dispersion of dipole-exchange spin waves.Comment: 13 pages, 5 figure

Advanced Technologies for Large-Sized OLED Display

Five years have passed, since the first 55″ full high-definition (FHD) OLED TV fabricated on Gen 8.5 glass was successfully launched into the TV market. For the time being, the size of OLED TV became diverse from 55″ to 77″, and the resolution was doubled into ultrahigh definition (UHD). The brightness and color gamut were enhanced, while the lower power consumption was realized. Utmost picture quality and slim form factor of OLED TV as well as the improved performance have made OLED TV recognized as the best premium TV. In this chapter, we describe the recent progress in three key technologies, which enable such an enhancement of performance in OLED TV, i.e., oxide thin-film transistor (TFT) and white organic light-emitting diode (WOLED), compensation circuit, and method to compensate the nonuniformity of oxide TFTs, OLED devices, and luminance

The impact of the prenatal ultrasonography on birth of babies with Korean pediatric surgical index diseases

PURPOSE: The purpose of this study is to examine the impact of prenatal ultrasonography (US) on the birth of babies with diseases listed on the Korean pediatric surgery index diseases (IDs). METHODS: Depending the ease of diagnosis using prenatal US, [diagnostic facility if prenatal US] IDs were divided into easily diagnosed (ED), not easily diagnosed (NED) and detected with difficulty (DD) groups. Five-year data were obtained for the total live birth number (TBN) from the Korean Statistical Information Service, and the actual birth number of IDs (ABNID) from the Korean Health Insurance Review and Assessment Service. The certified incidences of IDs (I) were obtained from a prestigious textbook of pediatric surgery. The estimated abortion rate (AR) of fetus in each group was obtained using the following formula: AR (%) = [1 - (ABNID)/(TBN x I)] x 100. RESULTS: The AR with all IDs was 38 to 77%. The AR was 78 to 93% for ED group, 38 to 66% for NED group and 0% for DD group. CONCLUSION: In spite of high survival rates after treatment, the AR of each group depends on the ease of diagnosis using prenatal US in Korea. A recommendatory policy for the fetus with IDs should be urgently established after general consensus within the related medical societiesope

Facile Method to Prepare for the Ni2P Nanostructures with Controlled Crystallinity and Morphology as Anode Materials of Lithium-Ion Batteries

Conversion reaction materials (transition metal oxides, sulfides, phosphides, etc.) are attractive in the field of lithium-ion batteries because of their high theoretical capacity and low cost. However, the realization of these materials in lithium-ion batteries is impeded by large voltage hysteresis, high polarization, inferior cycle stability, rate capability, irreversible capacity loss in first cycling, and dramatic volume change during redox reactions. One method to overcome these problems is the introduction of amorphous materials. This work introduces a facile method to synthesize amorphous and crystalline dinickel phosphide (Ni2P) nanoparticle clusters with identical morphology and presents a direct comparison of the two materials as anode materials for rechargeable lithium-ion batteries. To assess the effect of crystallinity and hierarchical structure of nanomaterials, it is crucial to conserve other factors including size, morphology, and ligand of nanoparticles. Although it is rarely studied about synthetic methods of well-controlled Ni2P nanomaterials to meet the above criteria, we synthesized amorphous, crystalline Ni2P, and self-assembled Ni2P nanoparticle clusters via thermal decomposition of nickel-surfactant complex. Interestingly, simple modulation of the quantity of nickel acetylacetonate produced amorphous, crystalline, and self-assembled Ni2P nanoparticles. A 0.357 M nickel-trioctylphosphine (TOP) solution leads to a reaction temperature limitation (similar to 315 degrees C) by the nickel precursor, and crystalline Ni2P (c-Ni2P) nanoparticles clusters are generated. On the contrary, a lower concentration (0.1 M) does not accompany a temperature limitation and hence high reaction temperature (330 degrees C) can be exploited for the self-assembly of Ni2P (s-Ni2P) nanoparticle clusters. Amorphous Ni2P (a-Ni2P) nanoparticle clusters are generated with a high concentration (0.714 M) of nickel-TOP solution and a temperature limitation (similar to 290 degrees C). The a-Ni2P nanoparticle cluster electrode exhibits higher capacities and Coulombic efficiency than the electrode based on c-Ni2P nanoparticle clusters. In addition, the amorphous structure of Ni2P can reduce irreversible capacity and voltage hysteresis upon cycling. The amorphous morphology of Ni2P also improves the rate capability, resulting in superior performance to those of c-Ni2P nanoparticle clusters in terms of electrode performance

Two-Year Changes in Diabetic Kidney Disease Phenotype and the Risk of Heart Failure: A Nationwide Population-Based Study in Korea

Background Diabetic kidney disease (DKD) is a risk factor for hospitalization for heart failure (HHF). DKD could be classified into four phenotypes by estimated glomerular filtration rate (eGFR, normal vs. low) and proteinuria (PU, negative vs. positive). Also, the phenotype often changes dynamically. This study examined HHF risk according to the DKD phenotype changes across 2-year assessments. Methods The study included 1,343,116 patients with type 2 diabetes mellitus (T2DM) from the Korean National Health Insurance Service database after excluding a very high-risk phenotype (eGFR <30 mL/min/1.73 m2) at baseline, who underwent two cycles of medical checkups between 2009 and 2014. From the baseline and 2-year eGFR and PU results, participants were divided into 10 DKD phenotypic change categories. Results During an average of 6.5 years of follow-up, 7,874 subjects developed HHF. The cumulative incidence of HHF from index date was highest in the eGFRlowPU– phenotype, followed by eGFRnorPU+ and eGFRnorPU–. Changes in DKD phenotype differently affect HHF risk. When the persistent eGFRnorPU– category was the reference, hazard ratios for HHF were 3.10 (95% confidence interval [CI], 2.73 to 3.52) in persistent eGFRnorPU+ and 1.86 (95% CI, 1.73 to 1.99) in persistent eGFRlowPU–. Among altered phenotypes, the category converted to eGFRlowPU+ showed the highest risk. In the normal eGFR category at the second examination, those who converted from PU– to PU+ showed a higher risk of HHF than those who converted from PU+ to PU–. Conclusion Changes in DKD phenotype, particularly with the presence of PU, are more likely to reflect the risk of HHF, compared with DKD phenotype based on a single time point in patients with T2DM

Fatty liver disease and the risk of erosive oesophagitis in the Korean population: a cross-sectional study

Objectives To investigate an association between fatty liver disease (FLD) and erosive oesophagitis. Design and setting This was a cross-sectional study of subjects selected from examinees who underwent health check-up, including oesophagogastroduodenoscopy in one hospital between 2004 and 2011. Erosive oesophagitis was classified according to the Los Angeles classification and FLD was diagnosed with ultrasonography. The anthropometric and laboratory data of the subjects were analysed using X-2 test and multivariate logistic regression. Additionally, we have analysed our data with two-stage least square estimation using the Baltagi-Chang one-way model to clarify unobserved confounding variable. Primary outcome measure The effect of FLD on erosive oesophagitis. Results Among the 14 723 eligible subjects, 4232 (28.7%) subjects diagnosed with FLD were classified into the fatty liver group and 10 491 (71.3%) subjects without FLD were classified into the non-fatty liver group. The incidence rate of erosive oesophagitis was significantly higher in the fatty liver group than in the non-fatty liver group (10.4% vs6.1%, p< 0.0001). The multivariate analysis revealed that the fatty liver group was significantly associated with erosive oesophagitis (OR 1.19, 95% CI 1.03 to 1.37, p= 0.016). Conclusion FLD diagnosed by ultrasonography is an independent risk factor of erosive oesophagitis. It suggests that FLD-related metabolic abnormality may be associated with erosive oesophagitis