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Background: X‐ray fluorescence (XRF) imaging for metal nanoparticles (MNPs) is a promising molecular imaging modality that can determine dynamic biodistributions of MNPs. However, it has the limitation that it only provides functional information. Purpose: In this study, we aim to show the feasibility of acquiring functional and anatomic information on the same platform by demonstrating a dual imaging modality of pinhole XRF and computed tomography (CT) for gold nanoparticle (GNP)‐injected living mice. Methods: By installing a transmission CT detector in an existing pinhole XRF imaging system using a two‐dimensional (2D) cadmium zinc telluride (CZT) gamma camera, XRF and CT images were acquired on the same platform. Due to the optimal X‐ray spectra for XRF and CT image acquisition being different, XRF and CT imaging were performed by 140 and 50 kV X‐rays, respectively. An amount of 40 mg GNPs (1.9 nm in diameter) suspended in 0.20 ml of phosphate‐buffered saline were injected into the three BALB/c mice via a tail vein. Then, the kidney and tumor slices of mice were scanned at specific time points within 60 min to acquire time‐lapse in vivo biodistributions of GNPs. XRF images were directly acquired without image reconstruction using a pinhole collimator and a 2D CZT gamma camera. Subsequently, CT images were acquired by performing CT scans. In order to confirm the validity of the functional information provided by the XRF image, the CT image was fused with the XRF image. After the XRF and CT scan, the mice were euthanized, and major organs (kidneys, tumor, liver, and spleen) were extracted. The ex vivo GNP concentrations of the extracted organs were measured by inductively coupled plasma mass spectrometry (ICP‐MS) and L‐shell XRF detection system using a silicon drift detector, then compared with the in vivo GNP concentrations measured by the pinhole XRF imaging system. Results: Time‐lapse XRF images were directly acquired without rotation and translation of imaging objects within an acquisition time of 2 min per slice. Due to the short image acquisition time, the time‐lapse in vivo biodistribution of GNPs was acquired in the organs of the mice. CT images were fused with the XRF images and successfully confirmed the validity of the XRF images. The difference in ex vivo GNP concentrations measured by the L‐shell XRF detection system and ICP‐MS was 0.0005–0.02% by the weight of gold (wt%). Notably, the in vivo and ex vivo GNP concentrations in the kidneys of three mice were comparable with a difference of 0.01–0.08 wt%. Conclusions: A dual imaging modality of pinhole XRF and CT imaging system and L‐shell XRF detection system were successfully developed. The developed systems are a promising modality for in vivo imaging and ex vivo quantification for preclinical studies using MNPs. In addition, we discussed further improvements for the routine preclinical applications of the systems. [ABSTRACT FROM AUTHOR]

Uveal melanoma(UM) is the most common primary intraocular malignancy in adults. However, the incidence of UM in Asia is 10 to 20 times less than in Western populations. Therefore, for the first time, we report our whole exome sequencing (WES) data analysis to discover differences in the molecular features of Asian and Western UM, and to determine the disparities between the primary tumor before brachytherapy and enucleated samples after brachytherapy. WES of 19 samples (13 primary tumors, 5 enucleation samples after brachytherapy, and 1 liver metastasis) from 13 patients diagnosed with UM and treated between 2007 and 2019 at the Yonsei University Health System (YUHS) were analyzed using bioinformatics pipelines. We identified significantly altered genes in Asian UM and changes in mutational profiles before and after brachytherapy using various algorithms. GNAQ, BAP1, GNA11, SF3B1 and CYSLTR2 were significantly mutated in Asian UM, which is similar that reported frequently in previous Western-based UM studies. There were also similar copy number alterations (M3, 1p loss, 6p gain, 8q gain) in both groups. In paired comparisons of the same patients, DICER1 and LRP1B were distinctly mutated only in tumor samples obtained after brachytherapy using rare-variant association tests (P = 0.01, 0.01, respectively). The mutational profiles of Asian UM were generally similar to the data from previous Western-based studies. DICER1 and LRP1B were newly mutated genes with statistical significance in the regrowth samples after brachytherapy compared to the primary tumors, which may be related to resistance to brachytherapy. [ABSTRACT FROM AUTHOR]

Introduction: Ewing sarcoma (ES) as a primary intracranial tumor is very rare. Recently, CNS embryonal tumors with ES-like genomic change have been reported. Patients and methods We report a case of intracranial Ewing sarcoma in a 13-year-old girl who complained of headache and migraine. The tumor had developed in the right middle cranial fossa with a mass effect on the brain with impending transuncal herniation.Results: Undifferentiated small round cell morphology with completely negative results for friend leukemia integration 1 transcription factor (Fli-1) and a nonspecific cytoplasmic CD99-positive staining pattern mislead the diagnosis as central nervous system (CNS) embryonal tumor, NOS. However, whole genome sequencing (WGS) revealed Ewing sarcoma (EWS)-Fli-1 gene fusion, which was confirmed by fluorescence in situ hybridization study and the diagnosis was revised to ES.Conclusions: This case is a true intracranial but extra-axial ES confirmed by WGS. We report this case of intracranial ES to demonstrate the importance of marker gene studies using FISH or NGS. [ABSTRACT FROM AUTHOR]

This paper deals with the electrical characteristics of no-insulation coil wound with surface-processed HTS tape. The bypassing current path through turn-to-turn contacts within a coil is formed in the no-insulation coil, and this bypassing current path determines two characteristics: 1) self-protection and 2) charge-discharge delay. The amplitude of bypassing current is determined by contact resistance between the turn-to-turn contacts of the no-insulation coil. The surface roughness of the HTS tape is one of the parameters to change the contact resistance. The HTS tapes were processed to roughen by bead blast and abrasive paper, and the no-insulation coil is fabricated using processed HTS tape. We have studied the charge-discharge delay and self-protecting characteristic of each no-insulation coil by 1) sudden discharge tests and 2) overcurrent tests. The FEM simulations of contact resistance of no-insulation coil were carried out. The contact surface resistance of a case processed by abrasive paper has almost three times larger than that of reference no-insulation coil, and a case processed by bead blast presents almost same contact surface resistance with reference no-insulation coil. [ABSTRACT FROM AUTHOR]

A current lead is a connecting device between the superconducting magnet and the power supply. A large amount of heat transfer ocurrs through the current lead because the cold-end in a superconducting system is thermally linked with the warm-end part. Therefore, high-Tc superconductor (HTS) is used in the current lead for a tokamak system. However, it is hard to consider the dependance of HTS's critical current with respect to temperature because the conventional HTS current leads consist of the HTS tapes with the same width and thickness, and their critical currents can differ from their temperature. For this reason, cold-end of the HTS section in current lead is designed excessively than necessary specifications. This generates the additional heat transfer between cold-end and warm-end within the HTS current lead. In this paper, a study on the HTS current leads with asymmetric structure is conducted to reduce the heat transfer by reducing the cross-sectional area of the HTS current lead. Asymmetric current leads are fabricated considering the design parameters about heat transfer within the HTS current lead. Current transporting tests on the conventional, symmetrical, and asymmetrical HTS current leads are performed to confirm the feasibility of the suggested design. And then, heat load of the asymmetric current lead is compared with the symmetric current lead. From this study, it is found that heat load of the current lead is reduced by using the asymmetric HTS current lead. [ABSTRACT FROM PUBLISHER]

Superconducting magnet systems operated at cryogenic temperature require high temperature superconducting (HTS) current leads to reduce the heat intrusion from the power supply at room temperature. However, some kinds of accidents, such as cryogenic failure, can cause a quench in the HTS current lead. Since the current conducting through the HTS current lead is very large, the quench in a HTS part can lead to a severe device failure. Therefore a study of a protection method for the HTS current lead is important. Generally, the HTS part of current lead used in large scale magnet systems has multiple separated HTS tape strands. They are electrically not connected or poorly connected. Therefore the quench in one strand affects other strands in current lead by applying additional loads for the other parts of the HTS current lead. In this paper, a strand-to-strand bridging method with HTS tapes is proposed as a quench protection method. Small scale HTS current leads with 2G HTS tapes and the suggested bridging method have been fabricated and tested. [ABSTRACT FROM PUBLISHER]

This paper presents a numerical analysis on MW-class high-temperature superconducting (HTS) synchronous generator, especially focusing on damper layer design. Our research program to develop a large-scale HTS wind turbine generator (WTG) core technology, a two-dimensional electromagnetic FEM model of the direct-drive HTS WTG, comprised of 24 air-core type HTS race track coils (24 poles), has been built. The damper is used for stable operation of HTS field coil against varying magnetic field by change of rotation speed. This model is designed to obtain basic operating parameters for HTS WTG, including magnetic field distribution and induced electromotive force, in static and transient condition. First, the parameters in static condition, which means that the rotating speed is constant, are compared with our design parameters to confirm the feasibility of our numerical analysis. Second, in transient condition, we focused on the reaction between rotating magnetic field and its stator components, damper, and armature winding. By changing damper material having different electrical conductivity and magnetic permeability, we concluded our damper design to be applicable to our MW-class HTS synchronous generator model. [ABSTRACT FROM PUBLISHER]

This paper describes new kind of HTS (High Temperature Superconducting) element for current leads, which can transfer large electric current in the nuclear fusion system. Since the HTS tapes have no resistance and the generated Joule heat is also very small compared to the conventional current leads, cooling costs of the current leads can be reduced. For this reason, the various feasibility researches for HTS current leads have been promisingly progressed in the superconducting power applications. However, there is a limitation on the capability of current carrying for single HTS tape. In addition, the cross-sectional area of the current leads should be small enough to minimize the heat conducted through the HTS current leads. In order to improve the current carrying capacity of the current leads, multiple HTS tapes are required. In this paper, we proposed several structures of compact HTS current leads and compare them other 2 kA class current leads. We report on the calculated characteristics of stabilized HTS current leads and on the performance measured during critical current measurement tests. [ABSTRACT FROM PUBLISHER]

Simple Summary: We have developed and analytically validated the Korean Pan-cancer Companion Diagnostic (CDX) Panel to apply targeted anticancer drugs to Korean patients based on the molecular characteristics of tumors using tumor samples without matched patient normal samples. The panel included 31 genes with reported single nucleotide variants, 9 genes with reported copy number variations, and 15 genes with predictive responses to targeted drugs under clinical testing, enabling the panel to be analyzed for the targets of 30 targeted anticancer drugs. It is cost-effective and optimized for cancer type-specific therapy in Korean cancer patients across solid cancer types while minimizing the limitations of existing approaches. This gene screening method is expected to reduce test turnaround time and cost, making it a balanced approach to investigate solid cancer-related gene regions. Recently, several panels using two representative targeting methods have been developed but they do not reflect racial specificity, especially for Asians. We have developed and analytically validated the Korean Pan-cancer Companion Diagnostic (CDX) Panel to apply targeted anticancer drugs to Korean patients based on the molecular characteristics of tumors using tumor samples without matched patient normal samples. The panel included 31 genes with reported single nucleotide variants, 9 genes with reported copy number variations, and 15 genes with predictive responses to targeted drugs under clinical testing, enabling the panel to be analyzed for the targets of 30 targeted anticancer drugs. It is cost-effective and optimized for cancer type-specific therapy in Korean cancer patients across solid cancer types while minimizing the limitations of existing approaches. In addition, the optimized filtering protocol for somatic variants from tumor-only samples enables researchers to use this panel without matched normal samples. To verify the panel, 241 frozen tumor tissues and 71 formalin-fixed paraffin-embedded (FFPE) samples from several institutes were registered. This gene screening method is expected to reduce test turnaround time and cost, making it a balanced approach to investigate solid cancer-related gene regions. [ABSTRACT FROM AUTHOR]

This paper reports the effects of a current sweep cycle method on reducing the screening current induced field (SCF) in a (RE)Ba2Cu3Ox (REBCO) coil. The screening current induced field in a REBCO coil causes two major problems: temporal magnetic field drift and a reduction of the central magnetic field. This is a critical problem in relation to REBCO coils, which require a homogeneous and stable magnetic field, during, for instance, nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) applications (Itoh et al., 2013; Hemmi et al., 2005; Hahn et al., 2008; Amemiya et al., 2008; Otsuka et al., 2011; Yang et al., 2013; Ahn et al., 2009; Koyama et al., 2009; Kajikawa et al., 2015). In an effort to circumvent the SCF problem, the current sweep cycle method is investigated based on experiments in this study. The experimental results show that a greater SCF reduction in a REBCO coil can be obtained by increasing the overshooting of the current sweep cycle. [ABSTRACT FROM AUTHOR]

There are a number of AC power devices using high temperature superconductor (HTS) such as Superconducting Fault Current Limiter (SFCL), Superconducting Transformer, AC Superconducting cable and so on. However, the operating current of HTS power devices at alternating current (AC) circumstances is almost decided by critical current which is measured in direct current (DC) circumstances. Applying DC critical current criterion to AC power devices cannot be ideal. So, for AC power devices, a new AC critical current criterion must be needed. Commercial AC frequencies of current grid are 50 and 60 Hz. Therefore, in AC circumstance, the voltage induced by inductance is not negligible. [ABSTRACT FROM PUBLISHER]

Recently, studies of partially insulated, high-temperature superconducting (HTS) coils have shown application in the design and construction of compact, stable and self-protecting HTS coils. This article presents the electrical characteristics of HTS coils based on the turn-to-turn inserted materials and conditions. Three partially co-wound pancake coils were fabricated and tested. Each coil was partially co-wound with Kapton, stainless steel and copper tape at every fourth turn of the winding. Tested coils were co-wound on every turn with Kapton, stainless steel and copper tape, and coils without turn-to-turn insulation were the control group. Charge–discharge, sudden-discharge and over-current tests were performed to evaluate the performance of the fabricated coils. The experimental results show that the properties of materials inserted into the coil can control the time constant (τ). Therefore, HTS coils can be designed for specific purposes according to the time constant control. The experimental results of the study could be useful in designing HTS coil applications. [ABSTRACT FROM AUTHOR]