Phase equilibria, superconductivity, and flux creep in Nd1+[subscript x]Ba2-[subscript x]Cu3O7+[subscript delta] superconductors

NdBa[subscript]2Cu[subscript]3O[subscript]7 (Nd123) is one of REBa[subscript]2Cu[subscript]3O[subscript]7 (RE123) superconductors (RE = Y and rare earths), having the superconducting transition temperature (T[subscript] c) of about 90 K. From a processing standpoint, Nd123 is an interesting alternative to Y123 for applications because it exhibits both a higher peritectic decomposition temperature and a broader primary solidification range than Y123, and unlike Y123, the low temperature orthorhombic phase exists over a range of Nd compositions in Nd[subscript]1+xBa[subscript]2-xCu[subscript]3O[subscript]7+[delta] solid solution (Nd123ss) with little effect on T[subscript] c;In this study, the phase diagram in the Nd-Ba-Cu-O system, superconductivity in Nd123ss, and the role of Nd substitution for Ba sites as the magnetic flux pinning sites were investigated. In the phase diagram study, the discrepancies in the published phase diagrams were clarified. Significant results contain the solubility limits of 0.04 ≤ x ≤ 0.6 in Nd123ss, the existence of Nd[subscript]2BaCuO[subscript]10 having a solid solution, and a discovery of a new phase NdBa[subscript]6Cu[subscript]3O[subscript]y;Superconductivity in Nd[subscript]1+xBa[subscript]2-xCu[subscript]3O[subscript]7+[delta] was studied for well characterized samples with sharp transitions. With the substitution of Nd[superscript]+3 for Ba[superscript]+2, there is an increase in the O(5) sites surrounding this substitution. While for x \u3e 0.1 there is a significant depression of T[subscript] c, for x \u3c 0.1 there is no substantial decrease in T[subscript] c within experimental error. T[subscript] c vs x is characterized by two plateaus analogous to T[subscript] c vs d in YBa[subscript]2Cu[subscript]3O[subscript]7-d. Analysis of oxygen contents of Nd123ss suggests the analogy with Y123 is valid. The transition width and Meissner fraction for all Nd123ss samples are strongly dependent on the sintering temperature. Hysteresis measurements show good intragranular critical currents (J[subscript] c) at high fields but the intergranular J[subscript] c\u27s are still low;Since the magnetic fields penetrate a Type II superconductor at high field, flux lines must be pinned to increase the J[subscript] c. While T[subscript] c is not affected over the range 0 \u3c x \u3c 0.1, the oxygens surrounding the substituted Ba sites are expected to locally suppress the superconducting order parameter. Such a local suppression of the order parameter may act as a flux pinning site. Hysteresis measurements exhibit a small increase in the magnetic J[subscript] c, but flux creep measurements show no apparent effects of this substitution on the flux pinning energy

Direct numerical simulation of turbulent counterflow nonpremixed flames

This paper presents our recent progress in terascale three-dimensional simulations of turbulent nonpremixed flames in the presence of a mean flow strain and fine water droplets. Under the ongoing university collaborative project supported by the DOE SciDAC Program [1] along with the INCITE 2007 Project [2], the study aims at bringing the state-of-the-art high-fidelity simulation capability to the next level by incorporating various advanced physical models for soot formation, radiative heat transfer, and lagrangian spray dynamics, to an unprecedented degree of detail in high-fidelity simulation application. The targeted science issue is fundamental characteristics of flame suppression by the complex interaction between turbulence, chemistry, radiation, and water spray. The high quality simulation data with full consideration of multi-physics processes will allow fundamental understanding of the key physical and chemical mechanisms in the flame quenching behavior. In this paper, recent efforts on numerical algorithms and model development toward the targeted terascale 3D simulations are discussed and some preliminary results are presented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/58180/2/jpconf7_78_012029.pd

Global gene-expression profiles of intracellular survival of the BruAb2_1031 gene mutated Brucella abortus in professional phagocytes, RAW 264.7 cells

Background Since recognizing the interaction between Brucella and host cells is crucial to the elucidation of the infectious process, Brucella researches have prioritized the investigation of genes related to pathogenicity. To demonstrate the roles of Brucella genes, RAW 264.7 cells were infected with the Brucella abortus wild-type and mutant strains (generated using transposon mutagenesis), after which the different transcriptional responses of the infected cells were determined using microarray. Results Following infection, enhanced strategies for intracellular survival, such as down-regulation of genes associated with cytokine responses and apoptosis, were observed in RAW 264.7 cells infected with C3 mutant strain when compared to the transcriptional responses of wild-type infected cells. Using sequence analysis, we determined the mutation site of a C3 mutant strain as the ATP-binding cassette transporter permease (BruAb2_1031). These results were evidenced by an increased level of intracellular survival of the C3 mutant strain. Conclusions Characteristics of each mutant strain including bacterial growth rate, abilities to induce cytokine production in macrophages after infection, internalization, and levels of intracellular survival and replication, were investigated by performing RAW 264.7 cell infection experiments. Our results indicate that the BruAb2_1031 gene might be closely related with intracellular survival of B. abortus in RAW 264.7 cells.This work was supported by NRF grant of MSIP (No. 2014R1A2A2A01007291), Korea Health Industry Development Institute (HI16C2130), BK21 PLUS and Research Institute for Veterinary Science, Seoul National University, Seoul, Republic of Korea. The funders had no role in study design, data collection and interpretation, writing the manuscript and the decision to submit the work for publication

Phlegmonous Enteritis in a Patient with Congestive Heart Failure and Colon Cancer

Phlegmonous enteritis is a rare infective inflammatory disease of the intestine, predominantly involving the submucosal layer. It is difficult to diagnose and often fatal. Its association with alcoholism and various liver diseases, although rarely reported, is well documented. We report a case of phlegmonous enteritis in a male patient with congestive heart failure and colon cancer, and describe the ultrasonographic and CT findings

Clinical performance of medical students in Korea in a whole-task emergency station in the objective structured clinical examination with a standardized patient complaining of palpitations

This study assessed the clinical performance of 150 third-year medicalstudents in Busan, Korea in a whole-task emergency objective structured clinical examination station that simulated a patient with palpitations visiting the emergency department. The examination was conducted from November 25 to 27, 2019. Clinical performance was assessed as the number and percentage of students who performed history-taking (HT), a physical examination (PE), an electrocardiography (ECG) study, patient education (Ed), and clinical reasoning (CR), which were items on the checklist. It was found that 18.0% of students checked the patient’s pulse, 51.3% completed an ECG study, and 57.9% explained the results to the patient. A sizable proportion (38.0%) of students did not even attempt an ECG study. In a whole-task emergency station, students showed good performance on HT and CR, but unsatisfactory results for PE, ECG study, and Ed. Clinical skills educational programs for subjected student should focus more on PE, timely diagnostic tests, and sufficient Ed

Polarization-selective vortex-core switching by orthogonal Gaussian-pulse currents

We experimentally demonstrate low-power-consumption vortex-core switching in magnetic nanodisks using tailored rotating magnetic fields that are produced with orthogonal and unipolar Gaussian-pulse currents. Optimal width of the orthogonal pulses and their time delay are found to be determined only by the angular eigenfrequency {\omega}_D for a given vortex-state disk of its polarization p, such that {\sigma} = 1/{\omega}_D and {\Delta}t = {\pi}p/2{\omega}_D, as studied from analytical and micromagnetic numerical calculations. The estimated optimal pulse parameters are in good agreements with the experimentally found results. This work provides a foundation for energy-efficient information recording in vortex-core cross-point architecture.Comment: 32 pages, 10 figure

Diffusion Decay Coefficient for Chloride Ions of Concrete Containing Mineral Admixtures

The diffusion coefficient for chloride ions and the diffusion decay coefficient for chloride ions are essential variables for a service life evaluation of concrete structures. They are influenced by water-binder ratio, exposure condition, curing temperature, cement type, and the type and use of mineral admixture. Mineral admixtures such as ground granulated blast furnace slag, fly ash, and silica fume have been increasingly used to improve resistance against chloride ions penetration in concrete structures built in an offshore environment. However, there is not enough measured data to identify the statistical properties of diffusion decay coefficient for chloride ions in concrete using mineral admixtures. This paper is aimed at evaluating the diffusion decay coefficient for chloride ions of concrete using ordinary Portland cement or blended cement. NT BUILD 492 method, an electrophoresis experiment, was used to measure the diffusion coefficient for chloride ions with ages. It was revealed from the test results that the diffusion decay coefficient for chloride ions was significantly influenced by W/B and the replacement ratio of mineral admixtures

Interaction of turbulence, chemistry, and radiation in strained nonpremixed flames

This paper provides an overview of recent progress in our development of highfidelity simulation of turbulent combustion with detailed chemistry. In particular, two major accomplishments are presented and discussed: (a) As for the computational aspects, it was recognized that many existing techniques to treat inflow and outflow boundary conditions for compressible flow simulations suffered from spurious errors when applied to highly turbulent reacting flow problems. Upon careful examination, the sources of these problems have been identified and an improved characteristic boundary condition strategy has been developed. The new method has been applied to various test problems, thereby demonstrating that the improved boundary conditions can successfully reproduce complex combustion events in a finite domain size with desired accuracy and stability. (b) As a science application, more advanced physical models for soot formation and radiative heat transfer have been developed in order to provide fundamental understanding of the interaction among turbulence, chemistry and radiation. We have performed several parametric simulations of two-dimensional ethyleneair nonpremixed counterflow flames interacting with counter-rotating vortex pairs and injected turbulent flows to investigate transient dynamics of soot formation process. Detailed analysis on the transient characteristics of soot behavior is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49003/2/jpconf5_16_011.pd

Overcoming the electroluminescence efficiency limitations of perovskite light-emitting diodes.

Organic-inorganic hybrid perovskites are emerging low-cost emitters with very high color purity, but their low luminescent efficiency is a critical drawback. We boosted the current efficiency (CE) of perovskite light-emitting diodes with a simple bilayer structure to 42.9 candela per ampere, similar to the CE of phosphorescent organic light-emitting diodes, with two modifications: We prevented the formation of metallic lead (Pb) atoms that cause strong exciton quenching through a small increase in methylammonium bromide (MABr) molar proportion, and we spatially confined the exciton in uniform MAPbBr3 nanograins (average diameter = 99.7 nanometers) formed by a nanocrystal pinning process and concomitant reduction of exciton diffusion length to 67 nanometers. These changes caused substantial increases in steady-state photoluminescence intensity and efficiency of MAPbBr3 nanograin layers.This work was partially supported by Samsung Research Funding Center of Samsung Electronics under Project Number SRFC-MA-1402-07. A.S. was partially supported by the Engineering and Physical Sciences Research Council (UK).This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by the American Association for the Advancement of Science

Mannosylated-serum albumin nanoparticle imaging to monitor tumor-associated macrophages under anti-PD1 treatment

Background Immune checkpoint inhibitors such as anti-programmed cell death protein 1 (PD1) block tumor growth by reinvigorating the immune system; however, determining their efcacy only by the changes in tumor size may prove inaccurate. As the immune cells including macrophages in the tumor microenvironment (TME) are associ‑ ated with the response to anti-PD1 therapy, tumor-associated macrophages (TAMs) imaging using nanoparticles can noninvasively provide the immune enrichment status of TME. Herein, the mannosylated-serum albumin (MSA) nano‑ particle was labeled with radioactive isotope 68Ga to target the mannose receptors on macrophages for noninvasive monitoring of the TME according to anti-PD1 therapy. Results B16F10-Luc and MC38-Luc tumor-bearing mice were treated with anti-PD1, and the response to anti-PD1 was determined by the tumor volume. According to the fow cytometry, the responders to anti-PD1 showed an increased proportion of TAMs, as well as lymphocytes, and the most enriched immune cell population in the TME was also TAMs. For noninvasive imaging of TAMs as a surrogate of immune cell augmentation in the TME via anti-PD1, we acquired [ 68Ga] Ga-MSA positron emission tomography. According to the imaging study, an increased number of TAMs in responders at the early phase of anti-PD1 treatment was observed in both B16F10-Luc and MC38-Luc tumorbearing mice models. Conclusion As representative immune cells in the TME, non-invasive imaging of TAMs using MSA nanoparticles can refect the immune cell enrichment status in the TME closely associated with the response to anti-PD1. As non-inva‑ sive imaging using MSA nanoparticles, this approach shows a potential to monitor and evaluate anti-tumor response to immune checkpoint inhibitors.This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF), funded by the Ministry of Education (NRF-2020R1A6A3A13069409), the Korean government the Ministry of Science, ICT and Future Planning (2020R1A2C2010202, 2020R1A4A2002903, 2020M3A9B6038086, 2021M2E7A2079570, 2021R1A2C3009427, 2022M3E5F2018261), and the Ministry of Health and Welfare (HI19C0339, HN22C0644). This study also was carried out by the research fund supported by the fund project of Park Yang Sook - Chung Yung Ho in Seoul National University