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This paper proposes a novel approach to the modelling of HTS transformer-rectifier flux pumps that can charge HTS magnet-ic loads without the need for bulky current leads or expensive cryogenic requirements. The model was built in MATLAB/Simulink for a flux pump with 2 HTS switches, an HTS transformer with a primary inductance of 15 mH, second-ary inductance of 50 H and an HTS magnetic load with an in-ductance of 2 mH. With a 5 A pk-pk triangular current wave-form at 2 Hz the system can load the HTS load to 34.63 A in 5 s. This incremental addition of flux to the load demonstrates the advantage of flux pumps as they can charge high-field magnets without the need for large power sources. The speed of flux pumping is improved by increasing the system frequency, the magnitude of the dynamic voltage developed in the HTS switches and by increasing the primary inductance of the trans-former. This has widespread industrial applicability in fields such as the charging of high-field magnets for MRI systems.

Circular RNAs (circRNA) containing retained introns are normally sequestered in the nucleus. Dysregulation of cellular homeostasis can drive their nuclear export, which may be involved in cancer metastasis. However, the mechanism underlying circRNA nuclear export and its role in lymph node (LN) metastasis of bladder cancer remain unclear. Here, we identify an intron-retained circRNA, circNCOR1, that is significantly downregulated in LN metastatic bladder cancer and is negatively associated with poor prognosis of patients. Overexpression of circNCOR1 inhibited lymphangiogenesis and LN metastasis of bladder cancer in vitro and in vivo. Nuclear circNCOR1 epigenetically promoted SMAD7 transcription by increasing heterogeneous nuclear ribonucleoprotein L (hnRNPL)–induced H3K9 acetylation in the SMAD7 promoter, leading to inhibition of the TGFβ-SMAD signaling pathway. Nuclear retention of circNCOR1 was regulated by small ubiquitin-like modifier (SUMO)ylation of DDX39B, an essential regulatory factor responsible for circRNA nuclear-cytoplasmic transport. Reduced SUMO2 binding to DDX39B markedly increased circNCOR1 retention in the nucleus to suppress bladder cancer LN metastasis. By contrast, SUMOylated DDX39B activated nuclear export of circNCOR1, impairing the suppressive role of circNCOR1 on TGFβ-SMAD cascade activation and bladder cancer LN metastasis. In patient-derived xenograft (PDX) models, overexpression of circNCOR1 and inhibition of TGFβ signaling significantly repressed tumor growth and LN metastasis. This study highlights SUMOylation-induced nuclear export of circNCOR1 as a key event regulating TGFβ-SMAD signaling and bladder cancer lymphangiogenesis, thus supporting circNCOR1 as a novel therapeutic agent for patients with LN metastatic bladder cancer.Significance:This study identifies the novel intron-retained circNCOR1 and elucidates a SUMOylation-mediated DDX39B–circNCOR1–SMAD7 axis that regulates lymph node metastasis of bladder cancer.

Supplementary Data from Aberrant Nuclear Export of circNCOR1 Underlies SMAD7-Mediated Lymph Node Metastasis of Bladder Cancer

The hallmark of pancreatic ductal adenocarcinoma (PDAC) is an exuberant tumor microenvironment (TME) comprised of diverse cell types that play key roles in carcinogenesis, chemo-resistance, and immune evasion. Here, we propose a gene signature score through the characterization of cell components in TME for promoting personalized treatments and further identifying effective therapeutic targets. We identified three TME subtypes based on cell components quantified by single sample gene set enrichment analysis. A prognostic risk score model (TMEscore) was established based on TME-associated genes using a random forest algorithm and unsupervised clustering, followed by validation in immunotherapy cohorts from the GEO dataset for its performance in predicting prognosis. Importantly, TMEscore positively correlated with the expression of immunosuppressive checkpoints and negatively with the gene signature of T cells’ responses to IL2, IL15, and IL21. Subsequently, we further screened and verified F2R-like Trypsin Receptor1 (F2RL1) among the core genes related to TME, which promoted the malignant progression of PDAC and has been confirmed as a good biomarker with therapeutic potential in vitro and in vivo experiments. Taken together, we proposed a novel TMEscore for risk stratification and selection of PDAC patients in immunotherapy trials and validated effective pharmacological targets.

Background Synchronous para-aortic lymph node (PALN) metastasis from colorectal cancer (CRC) is rare, and the positive predictive value of pre-operative CT was low. This study aimed to clarify risk factors radiographic PALN metastasis in left-sided CRC for improving the accuracy of pre-operative CT scan. Patients and Methods: Patients with pathologically and radiographically confirmed diagnosis of left-sided CRC were enrolled between January 2019 and August 2021. The Correlations between clinicopathologic data and radiographic PALN metastasis were analyzed chi-squared test or Fisher exact test and the multivariate binary logistic regression model was used for multivariate analyses. Results There were 15(3.56%) patients with radiographic PALN metastasis. The hepatic (P = 0.023) and inferior mesenteric lymph nodes (IMLN) (P

Shengmai Yin (SMY) is a Chinese herbal decoction that effectively alleviates the side effects of radiotherapy in various cancers and helps achieve radiotherapy's clinical efficacy. In this study, we explored the interaction mechanism among SMY, DNA methylation, and nasopharyngeal carcinoma (NPC). We identified differences in DNA methylation levels in NPC CNE-2 cells and its radioresistant cells (CNE-2R) using the methylated DNA immunoprecipitation array and found that CNE-2R cells showed genome-wide changes in methylation status towards a state of hypomethylation. SMY may restore its original DNA methylation status, and thus, enhance radiosensitivity. Furthermore, we confirmed that the differential gene Tenascin-C (TNC) was overexpressed in CNE-2R cells and that SMY downregulated TNC expression. This downregulation of TNC inhibited NPC cell radiation resistance, migration, and invasion. Furthermore, we found that TNC was hypomethylated in CNE-2R cells and partially restored to a hypermethylated state after SMY intervention. DNA methyltransferases 3a may be the key protein in DNA methylation of TNC., Graphical abstract Image 1, Highlights • A significant difference in the genome-wide methylation status between Nasopharyngeal carcinoma CNE-2 cells and its radioresistant strain. • Shengmai Yin-mediated enhancement of radiosensitivity might be mediated by restoration of its original DNA methylation status. • Tenascin-C was downregulated and restored to partially hypermethylated in CNE-2R after Shengmai Yin intervention, DNMT3a maybe the key protein of DNA methylation of TNC. • The downregulation of TNC inhibited NPC cell radiation resistance, migration and invasion.

The HTS flux pump is a promising device which can charge the HTS magnet for various high field applications. In an HTS flux pump, the superconducting tapes are the circuit connections between the charging loop and the load circuit, and using soldering joints between the superconducting layers is a general method. For a large scale HTS flux pump, the joints should endure the electrical current over kA level, and with durable mechanical structures. In our kA level HTS flux pump, the HTS-copper joint was used to connect the charging loop, the HTS bridge and the potential HTS load. Three methods of HTS-copper soldering were tested and compared for a simple HTS-copper circuit: pure indium wire pre-tinning, IN52/SN48 ribbon direct soldering, and IN52/SN48 ribbon pre-tinning. Experiments show the soldering of IN52/SN48 ribbon pre-tinning archived the lowest joint resistance among these three methods, and the individual resistances were determined. This method was used to solder the joint for the kA level HTS flux pump, and acceptably low resistance was achieved.

The High Temperature Superconducting (HTS) Conductor on Round Core (CORC) cables have been widely utilized to fabricate various superconducting applications for power transmission, fusion, and magnets with high current density. Understanding the AC loss behavior of CORC cables during the cable design process is essential for analyzing its electromagnetic performance and evaluating its future industry potential. The aim of our research is to investigate the AC loss dependence caused by the magnitude and frequency of applied external variations to the magnetic field. This paper describes the simulation models of HTS CORC cables based on the finite-element method (FEM) by using an H-formulation in a commercial software named COMSOL Multiphysics. Three-dimensional (3-D) CORC models, with three HTS tapes wound around each layer, were built and analyzed. The 3-D CORC models, built using the FEM method, were then verified with published experimental results. AC losses dissipated in the CORC cables, resulting from applied external varying magnetic field, were calculated and examined.

The HTSConductor on Round Core (CORC) Cables have been widely recognized as the proper candidate for superconducting applications such as the high-field magnets and power transmission cables. This article presents the modeling of HTS CORC cables using the FEM H -formulation model merged into the package COMSOL Multi-physics. The 2D and 3D H -formulation models of HTS CORC cables were compared and analyzed. There were two important parameters in our CORC design: (1) the gap angle between the HTS tapes in a single layer, and, (2) the degree of twist for HTS tapes (normally identified as the pitch). The 2D CORC model has much faster solving speed over the 3D model and sometimes is able to model the AC loss in a reasonable range, while, the 3D CORC model has the advantages over 2D CORC model with respect to more information in each sector with the different conditions of two parameters above, and more realistic loss calculation.

The High-temperature Superconducting (HTS) magnet is one of the most promising technologies to accommodate various high field applications. With the high magnetic field, the quench problem of HTS material should be considered with extra care, and the specific quench protection scheme should be projected. In this article, the modeling of the quench protection of an HTS magnet for the MRI system is presented. The modeling strategy was composed of two stages: Stage 1 the HTS magnet was in the normal operation circuit, and Stage 2 the HTS magnet was switched to the heat dissipation circuit. The 1st stage was based on the finite element method (FEM) using the H -formulation together with the thermal-coupled model, which simulated the current distribution of typical HTS tapes and showed the process of temperature increase when the hot source occurred. The 2nd stage was based on the analytical model to investigate the reasonable damping resistance and the hot spot temperature of the HTS magnet.

Superconducting Conductor on Round Core (CORC) cables fabricated by several high temperature superconducting (HTS) tapes are able to carry enormous electrical current density, to be widely used in a variety of superconducting applications such as power transmission, fusion, and magnetic resonance imaging (MRI). However, the AC losses induced in the superconducting tapes under alternating current or magnetic field generate heat dissipation which can reduce the electric power efficiency. Therefore, it is essential to analyze the AC loss behavior of CORC cables as well as consider methods to reduce it. This paper presents an AC loss study of CORC cables with several different superconducting layer thicknesses. The CORC cable simulation model is built in a software suite named COMSOL Multiphysics utilising the finite-element method (FEM) solved by the three-dimensional (3-D) H -formulation. By implementing FEM simulations, the cases of increasing the degree of freedom of superconducting layers have been considered, and the AC losses of a single layer CORC cable model with three tapes mounted around the core have been calculated and analyzed for different layer thicknesses. Simulation results are verified with experimental results measured in previous literature.

Conductor on round core (CORC) cables wound by high-temperature superconducting (HTS) tapes have received much attention due to the advantages in power capacity and mechanical flexibility. This paper first developed a 3D model for a CORC cable through the finite-element method (FEM). Next, the total AC loss caused by transported current only was investigated, revealing the eddy current loss in the tube former contributes to the cable loss. The numerical CORC model was validated by published measurements. Moreover, the AC loss that resulted from a simultaneous presence of transport current and magnetic field was explored. With the induced current, the magnetisation loss generated in superconductors can increase the total loss. It is concluded that the addition of a magnetic field can result in a surge in the total loss of a current-carrying cable.

The potential application of the superconducting fault current limiter (SFCL) in a voltage source convert (VSC) system has received lots of attention. On the basis of the fault current limiting characteristics, this paper evaluated the loss level of saturated iron-core FCLs (SI-SFCLs) in a VSC-based distribution grid. The models of VSC network and the SI-SFCL model were respectively developed. Then, with and without the implementation of SI-SFCLs, the fault current process under positive-to-ground and positive-to-negative short-circuit was presented. Next, the power dissipated from the superconducting coil was curved. Analysis demonstrated the power dissipation of the SI-SFCL during the short-circuit is likely to reach tens of kilowatts. This study can provide a helpful guidance for the design of SI-SFCLs.

In order to meet the application requirements of fast-moving, accurate positioning, and low cost, a new type of pneumatic electric hybrid actuator was developed with a positioning accuracy of 0.01 mm. It was found that the velocity fluctuation would occur in the process of driving switching due to the “stop then restart” strategy, resulting in stumbling when positioning. To solve this problem, the basic characteristics of the drive switching mechanism were tested and analyzed. A driving switching strategy called “relay and run” was proposed based on the response characteristics of the locking mechanism in the braking stage and the starting characteristics of the motor. The uniform acceleration was controlled by the motor drive to compensate for the velocity loss so that the overall velocity was slowly reduced. The control model was established, and the experiments were conducted. The results showed that the relay and run switching strategy can eliminate the velocity fluctuation caused by the stop then restart strategy.

While the best technique for pancreatic anastomosis during Whipple’s procedure remains controversial, laparoscopic pancreaticoduodenectomy (LPD) has been rapidly increasing in popularity. Because of their feasibility and reliability, new pancreatic anastomosis techniques may have vital roles when adapted for LPD. Here, we describe a new pancreaticojejunostomy (PJ) technique using three sutures (termed the “three sutures” PJ technique), which facilitates pancreatic anastomosis during total LPD. A total of 149 patients who underwent LPD using the “three sutures” PJ technique at three hospitals were included in this study (81 patients at Guangdong Provincial People’s Hospital [GDPH], 60 patients at Sun Yat-Sen Memorial Hospital [SMH], and 8 patients at Affiliated Hospital of Guangdong Medical University [AHGMU]). Data on the demographic characteristics, operative outcomes, and postoperative results (pancreatic fistula rate, mortality rate, and length of hospital stay) of these patients were collected and analyzed. A surgical video showing the details of the “three sutures” PJ method was included. The mean operation times at GDPH, SMH, and AHGMU were 4.08 ± 0.99 h, 4.65 ± 1.53 h, and 4.67 ± 0.64 h, respectively, and the average PJ times were 17.96 ± 3.49 min, 18.19 ± 2.63 min, and 22.5 ± 3.96 min, respectively. The numbers of grade B pancreatic fistulas were 9 (11.11%), 2 (3.33%), and 1 (12.50%), respectively, and two patients had grade C fistulas, one each at GDPH and SMH. The numbers of clinically relevant postoperative pancreatic fistula (CR-POPF) were 10 (12.35%), 3 (5.00%), and 1 (12.50%) in each center, respectively. The overall rate of CR-POPF was 9.40% (14/149) among patients of all three centers. The perioperative mortality rate was 0%. The “three sutures” PJ technique for total LPD is a safe and reliable method, with a low risk of pancreatic fistula, short anastomosis time, and steep learning curve.

BackgroundCellular RNA-binding proteins (RBPs) have multiple roles in post-transcriptional control, and some are shown to bind DNA. However, the global localization and the general chromatin-binding ability of RBPs are not well-characterized and remain undefined in hematopoietic cells.ResultsWe first provide a full view of RBPs’ distribution pattern in the nucleus and screen for chromatin-enriched RBPs (Che-RBPs) in different human cells. Subsequently, by generating ChIP-seq, CLIP-seq, and RNA-seq datasets and conducting combined analysis, the transcriptional regulatory potentials of certain hematopoietic Che-RBPs are predicted. From this analysis, quaking (QKI5) emerges as a potential transcriptional activator during monocytic differentiation. QKI5 is over-represented in gene promoter regions, independent of RNA or transcription factors. Furthermore, DNA-bound QKI5 activates the transcription of several critical monocytic differentiation-associated genes, including CXCL2, IL16, and PTPN6. Finally, we show that the differentiation-promoting activity of QKI5 is largely dependent on CXCL2, irrespective of its RNA-binding capacity.ConclusionsOur study indicates that Che-RBPs are versatile factors that orchestrate gene expression in different cellular contexts, and identifies QKI5, a classic RBP regulating RNA processing, as a novel transcriptional activator during monocytic differentiation.

Purpose Synchronous para-aortic lymph node (PALN) metastasis from colorectal cancer (CRC) is rare, and the positive predictive value of pre-operative CT was low. This study aimed to clarify risk factors radiographic PALN metastasis in left‐sided CRC for improving the accuracy of pre-operative CT scan. Methods Patients with pathologically and radiographically confirmed diagnosis of left-sided CRC were enrolled between January 2019 and August 2021. The Correlations between clinicopathologic data and radiographic PALN metastasis were analyzed chi-squared test or Fisher exact test and the multivariate binary logistic regression model was used for multivariate analyses. Results There were 15(3.56%) patients with radiographic PALN metastasis. The hepatic (P=0.023) and inferior mesenteric lymph nodes (IMLN) (PConclusion Some clinicopathologic characteristics, especially IMLN metastasis, are the risk factors for PALN metastasis.

Background Breast cancer has surpassed lung cancer as the most common cancer. Day surgery for breast cancer has been widely carried out worldwide, but the development of day surgery in China is relatively slow. To reduce the spread of coronavirus 2019 (COVID-19), major surgery centres have optimized the management procedures of day surgery to different degrees. However, relevant research on whether the rapid turnover of day surgery and the excessive human resources placed in the prevention and control of the COVID-19 epidemic will affect the quality of day surgery is lacking. Method The demographic data, clinical data and postoperative complications of breast cancer patients in the single medical group of West China Hospital of Sichuan University from March 2020 to June 2021 were retrospectively collected, and the complications after discharge and the safety of day surgery were analysed. Results The average age significantly differed between the ward surgery group (WS) and the day surgery group (DS) (P = 0.030). Regarding postoperative complications, no significant differences were detected in total surgical complications (P = 0.676) or anaesthesia complications (P = 0.126) between the two groups. In the logistic analysis, day surgery was not a risk factor for postoperative complications during the COVID-19 pandemic (P = 0.676, OR = 1.154, 95% CI: 0.590–2.257). An increase in age significantly increased the incidence of postoperative surgical complications (P = 0.024, OR = 1.051, 95% CI: 1.007–1.097). At the same time, lymph node dissection after sentinel lymph node biopsy also led to an increase in the incidence of postoperative surgical complications (P = 0.030, OR = 3.372, 95% CI: 1.125–10.106). In the survival curve, no significant difference in DFS was detected between the two groups (P = 0.353). Conclusion Radical mastectomy at day surgery centres is safe and reliable under strict COVID-19 management guidelines.

The conductor on round core (CORC) cable wound with second-generation high-temperature superconducting (HTS) tapes is a promising cable candidate with superiority in current capacity and mechanical strength. The composing superconductors and the former are tightly assembled, resulting in a strong electro-magnetic interaction between them. Correspondingly, the AC loss is influenced by the cable structure. In this paper, a 3D finite-element model of the CORC cable is first built, and it includes the complex geometry, the angular dependence of critical current and the periodic settings. The modelling is verified by the measurements conducted for the transport loss of a two-layer CORC cable. Subsequently, the simulated results show that the primary transport loss shifts from the former to the superconductors as the current increases. Meanwhile, the loss exhibited in the outer layer is larger than that of the inner layer, which is caused by the shielding effect among layers and the former. This also leads to the current inhomogeneity in CORC cables. In contrast with the two-layer case, the simulated single-layer structure indicates stronger frequency dependence because the eddy current loss in the copper former is always dominant without the cancellation of the opposite-wound layers. The core eddy current of the single structure is denser on the outer surface. Finally, the AC transport losses among a straight HTS tape, a two-layer cable and a single-layer cable are compared. The two-layer structure is confirmed to minimise the loss, meaning an even-numbered arrangement makes better use of the cable space and superconducting materials. Having illustrated the electro-magnetic behaviour inside the CORC cable, this work is an essential reference for the structure design of CORC cables.

Magnetic Resonance Imaging (MRI) is an indispensable tool in monitoring lipid-rich tissues and the musculoskeletal system. It however requires maintaining a huge homogeneous (1 to 7 T) field. That is where superconductors come into play since they are the only feasible way to create such fields. The state-of-the-art technology utilizes low critical temperature superconductors (LTS) which require cooling down to liquid helium temperatures (4.2K). The new generation superconductors, aka the high critical temperature superconductors (HTS), can operate up to relatively elevated temperatures (technically above 100K's). In addition to that, they can withstand larger magnetic field strengths which can theoretically go up to the order of hundred Teslas in magnitude. It is evident that LTS wires of current MRI magnet technology is at their limits and new pursuits such as reaching higher fields and reducing operational/maintenance costs are in the favor of HTS tapes. There is, in fact, another advantage beyond minimization of the cryogenic costs, namely the compactness of the overall system. Utilizing certain auxiliary techniques such as flux pumping and conductive cooling of the tapes, MRI magnets can be reduced in size substantially. That, in turn, enables constructing much smaller thus mobile MRI scanners which can be brought to patients’ doorsteps. Here we present the current status of our project aiming to build an HTS MRI machine dedicated to use as a mobile head scanner.

When a superconductor is exposed to an AC magnetic field whilst carrying a constant DC transport current, a DC electrical resistance can be observed, commonly referred to as “dynamic resistance”. This dissipative effect can play a critical role in many potential high-temperature superconducting (HTS) applications, especially for the AC-field-actuated HTS switch, which is the key component in the HTS transformer-rectifier flux pump (TRFP). The characteristics of the HTS switch determine the performance and reliability of TRFP. In this paper, we report a numerical study of a new HTS switch design made of series-connected YBCO stacks. This study aims to obtain insights into the characteristics of dynamic resistance and power loss, including their relationships with the amplitude and the frequency of the AC magnetic field. The energy conversion efficiency of the HTS switch is also investigated. This work will help design a high-performance AC-field-actuated HTS switch.

A novel pneumatic-electric hybrid actuator is studied and developed to enable precise positioning within a cylinder stroke in industrial automation. The proposed actuator will also allow engineers to overcome the defects of bias torque and structural coupling in the parallel type of pneumatic-electric hybrid actuators. The novel hybrid actuator consists of a coaxial cylinder layout, the motor lead screw pair, and the position sensor; a serial driving pattern is applied. A special reconfigurable positioning structure is designed for both the fixed and moving module; therefore, a decoupling motion can be achieved for the fast pneumatic motion and the electric precise fine-tuning motion without interference. In this paper, the authors presented the structure of this novel pneumatic-electric hybrid actuator and the accompanying mathematical model for pneumatic-electrical driving. Additionally, the control strategy with proportional-fuzzy mode and the subsection frequency control mode are presented. Experimental results show that the pneumatic-electric hybrid actuator has satisfying motion characteristics, including high speed, low overshoot, and small load sensitivity. Its positioning accuracy is ±0.01 mm, with a positioning time within 2 s, which is better than that of current pneumatic localizable actuators and pneumatic-electric hybrid actuators.

Aims: Using Single-cell RNA sequencing (scRNA-seq), we explored the spatiotemporal heterogeneity of pancreatic neuroendocrine tumors (pNETs) and the underlying mechanism for malignant progression. Methods: scRNA-seq was conducted on three tumor tissues (two primary tissues from different sites, one liver metastatic lesion), one normal liver tissue, and peripheral blood mononuclear cells from one patient with a metastatic G2 pNET, followed by bioinformatics analysis and validation in a pNETs cohort. Results: The transcriptome data of 24.544 cells were obtained. We identified subpopulations of functional heterogeneity within malignant cells, immune cells, and fibroblasts. There were intra- and inter-heterogeneities of cell subpopulations for malignant cells, macrophages, T cells, and fibroblasts among all tumor sites. Cell trajectory analysis revealed several hallmarks of carcinogenesis, including the hypoxia pathway, metabolism reprogramming, and aggressive proliferation, which were activated at different stages of tumor progression. Evolutionary analysis based on mitochondrial mutations defined two dominant clones with metastatic capacity. Finally, we developed a gene signature (PCSK1 and SMOC1) defining the metastatic potential of the tumor and its prognostic value was validated in a cohort of thirty G1/G2 patients underwent surgical resection. Conclusions: Our scRNA-seq analysis revealed intra- and intertumor heterogeneities in cell populations, transcriptional states, and intercellular communications among primary and metastatic lesions of pNETs. The single-cell level characterization of the spatiotemporal dynamics of malignant cell progression provided new insights into the search for potential novel prognostic biomarkers of pNETs.

Pylorus-preserving gastrectomy (PPG) has been accepted as a representative function-preserving procedure for early gastric cancer (EGC) in the middle stomach. Totally, intracorporeal laparoscopic gastrectomy can provide better aesthetics, be less invasive, and allow faster postoperative recovery. Here, we first describe the surgical procedure of totally laparoscopic pylorus-preserving gastrectomy with intracorporeal hand-sewn anastomosis (TLPPG-IHSA). After standard procedure of lymph node dissection and middle stomach resection, we used two double-needle barbed sutures to perform a layer-to-layer manual anastomosis of the anterior and posterior walls in the abdominal cavity. Twelve patients with preoperatively diagnosed clinical EGC located in the middle third of the stomach underwent TLPPG-IHSA between August 2019 and January 2021. A total of 12 patients with EGC successfully underwent TLPPG-IHSA. Only one patient (8.3%) suffered postoperative gastric stasis. No complications or recurrence occurred in other patients during half a year after surgery. TLPPG-IHSA is considered technically feasible to treat EGC located in the middle third of the stomach.

High- $T_{c}$ superconducting (HTS) materials are extremely promising for high-field applications, due to their relatively high upper critical field. Flux pumps are a means ofenergizing closed superconducting magnets without direct electrical contact. Simulation is a good method to understand the physics of the flux pumping system. In this paper, we propose a simulation methodology for a transformer–rectifier HTS flux pump. A model is built, based on the electrical circuit. The simulation methodology opens up various opportunities for flux pump developers to design the whole superconducting magnet energizing system.

© 2002-2011 IEEE. The application of resistive superconducting fault current limiters (R-SFCLs) in voltage source converter (VSC)-based DC systems has been proposed, and the encapsulated high temperature coated conductors (HTS-CCs) used for R-SFCLs is getting practical. Thus, this paper respectively develops a 1-D HTS-CC model and a 2-D HTS-CC model with different thicknesses to investigate the resistance characteristics and the quench recovery time. The results show that the resistance of encapsulated HTS-CCs goes through the flux flow state before reaching the normal. Then, the encapsulation can expand the limit of fault current, and a suitable thickness is likely to reduce the total resistance of the R-FCL. Finally, due to the existence of the heat transfer between the HTS-CC surface and the liquid nitrogen bath, a thinner tape might recover faster, and the recovery time tends to rise slowly as the tolerated current increases.

Circular RNAs (circRNAs) are involved in cancer development via inhibition of miRNAs, which are associated with differentiation, proliferation, migration, and carcinogenicity. Curcumin has antioxidant and anti-cancer properties, and it has also been used as a radiosensitizer. In this study, we explored the potential relationships among curcumin, circRNAs, and nasopharyngeal carcinoma (NPC). We compared the differences in circRNA levels in NPC cell lines after radiotherapy and after treatment with curcumin, using a high-throughput microarray. Further, a circRNA-miRNA-mRNA interaction network between radiation resistance NPC cell lines and tumor stem cells was constructed by applying bioinformatics. Finally, it was demonstrated by reverse transcription-quantitative polymerase chain reaction assay and wound healing assay that curcumin could enhance radiosensitization of NPC cell lines via mediating regulation of tumor stem-like cells by the "hsa_circRNA_102115"-"hsa-miR-335-3p"-"MAPK1" interaction network.

Magnetic switches apply AC magnetic fields to DC current-carrying high temperature superconducting (HTS) tapes to generate DC voltages and are commonly used in the persistent current switches (PCSs) and flux pumps to charge HTS-coated conductor magnets. Normally, they are made of copper field coils and iron cores with narrow air gaps for the HTS tape to pass through. However, the perpendicular components of the self-field of the HTS tape in the air gap can be enhanced by the iron cores and cause a critical current reduction of up to 40% to the tape. If ignored, this reduction, rather than the magnets themselves, will limit the current carrying capability of the HTS magnets. To tackle this problem, we present analytical approximations to calculate the self-field distribution of a superconducting tape between iron cores. The approximate solutions are based on the method of images in electromagnetics to simplify the derivation and are then verified by the experiments and 3D finite element method models using the T–A formulation. The solutions are universal and can be applied to almost all the magnetic switches currently in use. A case study of typical magnetic switches shows that the solutions can be used to determine the critical current reduction quickly and accurately, analyse the influence of different parameters, and simplify the design process of magnetic switches. The results can significantly benefit the design and optimisation of PCSs and flux pumps for HTS magnet charging systems in the future.