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The bipolar DC micro-grid based on the Buck-Boost voltage balancer framework has been widely studied. The effective control voltage balancer keeps the positive and negative voltage of the system equal, to ensure the power quality of the system. Aiming at the control of Buck-Boost voltage balancer, a double integral sliding mode controller is designed. This method takes into account the nonlinearity and dynamic state of the system, and adopts double integral sliding surface to reduce the steady-state error. The experimental results show that compared with the traditional PI controller, the controller designed in this paper can effectively shorten the dynamic adjustment time and reduce the difference between positive and negative voltage.

A hybrid excitation multi-degree-of-freedom spherical motor (HE-MDOFSM) is designed, which can achieve MDOF motion by cooperatively controlling the excitation current in 12 sets of stator windings. The designed motor has the advantages of high power density and a large motion range. In addition, because the designed motor has an irregular three-dimensional (3D) structure, it is difficult to perform dynamic magnetic field calculations with existing methods. To solve this problem, we propose a modified 3D dynamic magnetic equivalent circuit (3DD-MEC). The proposed method establishes a node network according to the structural edge features of the motor core and the permanent magnet and calculates the reluctance of the connecting branch based on the differential principle. Moreover, a connection strategy of air-gap nodes in 3D space is formulated, and the magnetic saturation characteristics of the iron core are reflected by an iterative calculation of magnetic permeability. Using the 3DD-MEC method, the 3D dynamic magnetic field information of the HE-MDOFSM can be quickly and accurately calculated. Finally, the reliability of the method is verified by simulation and experiment, which provides a reference for improving the design optimization efficiency of HE-MDOFSM. [ABSTRACT FROM AUTHOR]

In this article, a sensorless control method based on signal injection and a high-pass filter (HPF) circuit is presented to control the unsymmetrical bistable multimagnetic circuit permanent magnetic actuator. In this method, a high-frequency sinusoidal signal was indirectly injected into the idle phase via a HPF circuit, and the peak of the high-frequency capacitance current was measured, which was used to calculate the idle phase inductance. Thereafter, the mover position was calculated by the one-to-one relationship between the idle phase inductance and the mover position. Combined with the HPF circuit and the proposed average current peak algorithm, the influences of back-EMF and coil resistance were eliminated. The magnetic saturation effects can also be ignored in the proposed strategy. The estimated noise, caused by measurement noise and signal distortion, was filtered using a simple mathematical filter. The flexibility and accuracy of the presented strategy were verified by simulation and experimental investigation. [ABSTRACT FROM AUTHOR]

A double‐stator swing rotating permanent magnet spherical motor (SR‐PMSM) is designed, which can realize rotation, swing and spiral motion, and is used in the multi‐degree‐of‐freedom motion fields of industrial robot joints, torque gyroscopes, panoramic photography tables and so on. The inner surface of the rotor of the motor is attached with cylindrical PM poles, and the outer surface is attached with trapezoidal PM poles. Cylindrical and trapezoidal PM poles are simple to manufacture, but the magnetic field model of a spherical motor with two kinds of PM poles is complex. Therefore, a magnetic field modelling method combining the geometric equivalence principle and analytical method is proposed. Using the method of shape approximation, according to the principle of equivalence, the key parameters of cylindrical PM poles and trapezoidal PM poles are replaced by the parameters of approximate dihedral PM poles in a spherical coordinate. Select the most suitable dihedral PM poles, establish the analytical model of the magnetic field in the spherical coordinate system and verify the analytical results by FEM method. A SR‐PMSM motor with 6/4 pole (swing) and 12/10 pole (rotation) structure was assembled, and the experimental device was set up. The experimental results show that the experimental curve, analytical curve and FEM curve are in good agreement, which proves the accuracy of the equivalent model and is suitable for the magnetic field model of cylindrical and trapezoidal PM poles of the spherical motor. The research results of magnetic field lay a foundation for further analysis of the stator–rotor composite magnetic field considering cogging effect and edge effect, and analysis of load characteristics of the motor. [ABSTRACT FROM AUTHOR]

A new type of double‐stator permanent magnet spherical motor (DSSRPMSM) is proposed. Compared with most existing spherical motors, this motor uses a large number of stator iron cores, which can generate larger magnetic flux density and significantly improve torque capacity. The proposed DSSRPMSM can continuously rotate, swing and spiral, and can be used in the multi‐degree‐of‐freedom motion fields of industrial robot joints, moment gyroscopes, panoramic photography tables and so on. Because the motor has the dual characteristics of rotary motor and arc linear motor, the comprehensive effects of stator slotting and stator iron core breaking should be considered. Cylindrical and trapezoidal PM poles are equivalent to dihedral PM poles, and stator coils are equivalent to PM pole models. Analytical models of PM pole magnetic field and stator magnetic field in a spherical coordinate system are established, and the air gap magnetic flux density under unequal magnetic potential boundary conditions is calculated by conformal transformation. The analytical calculation method proposed is consistent with the results of finite element method (FEM) simulation, and the experimental test further verifies the effectiveness and accuracy of this method. [ABSTRACT FROM AUTHOR]

This article presents a new type of double stator swing rotating permanent magnet spherical motor (DSSRPMSM), which can realize swing, rotation, and helical motion and is used in industrial robots, gyroscopes, satellite communications, and other fields. The proposed spherical motor consists of two stators and a hollow rotor with permanent magnet (PM) poles on its inner and outer surfaces. Compared with most spherical motor with hollow coil and traditional PM synchronous motor, the structure of the motor is different and novel, and it is difficult to find a more perfect design theory and method. Thus, this article introduces the new idea of motor design in detail. First, the structure and working principle of the motor are introduced, and the original design of the motor is carried out. The 2-D rough estimation and 3-D FEM accurate simulation calculation are carried out, and the electromagnetic characteristics of the motor are obtained, including magnetic flux density distribution, torque, and loss. The simulation results meet the design specifications of the motor. A prototype was built and tested. The experimental results are in good agreement with the 3-D FEM analysis. The design method provides a theoretical basis for the design of this kind of spherical motor. The research results lay a foundation for the subsequent optimization of the motor. [ABSTRACT FROM AUTHOR]

Primary central nervous system lymphoma (PCNSL) is an aggressive and rare malignancy with poor prognosis. However, there are no reliable prognostic biomarkers for PCNSL in clinical practice. Here, we aimed to identify a reliable prognostic biomarker for predicting the survival of PCNSL patients. In this study, multiplex immunofluorescence and digital imaging analysis were used to characterize tumor‐associated macrophages (TAMs) immunophenotypes and the expression of programmed cell death ligand 1 on TAMs, with regard to prognosis from diagnostic tumor tissue samples of 59 PCNSL patients. We found that the M2‐to‐M1 ratio was a more reliable prognostic biomarker for PCNSL than M1‐like or M2‐like macrophage infiltration. In addition, the combination of programmed death‐ligand 1 (PD‐L1) expression on TAMs and the M2‐to‐M1 ratio in PCNSL demonstrated improved performance in prognostic discrimination than PD‐L1‐positive TAMs or M2‐to‐M1 ratio. To validate the prognostic significance of the combined TAMs associated biomarkers, they were integrated into the International Extranodal Lymphoma Study Group (IELSG) index and termed as IELSG‐M index. Kaplan–Meier plots showed that the IELSG‐M index could discriminate patients into low‐, intermediate‐ or high‐risk subgroups, better than IELSG, in terms of prognosis. The areas under the receiver operating characteristic curves of IELSG‐M was 0.844 for overall survival; superior to the IELSG model (0.580). Taken together, this study's findings showed that the combination of PD‐L1 on TAMs and the M2‐to‐M1 ratio could be strong prognostic predictive biomarkers for PCNSL and the IELSG‐M index had improved prognostic significance than the IELSG index. [ABSTRACT FROM AUTHOR]

In this study, an unsymmetrical bistable multi‐magnetic circuit permanent magnetic actuator is proposed. The operating principle and mathematical model of the high‐voltage circuit breaker with the proposed machine are analysed. Additionally, the static and dynamic characteristics of the high‐voltage circuit breaker with the presented machine are investigated and evaluated using numerical finite element analysis methods. Furthermore, the influence of the length of the middle gap and the additional coil in the proposed machine are studied. The advantages of the presented machine, such as less magnet volume, low cost, high force density, and short starting time, are discussed. Finally, a prototype is created and tested, followed by the retrieval of the characteristic curves of the holding force to confirm the proposed design. [ABSTRACT FROM AUTHOR]

In this article, an asynchronous machine with ferrofluid in the gap (AM-WFIG) is analyzed. The principle of this machine was derived theoretically. The magnetic-flux density distribution inside the machine is analyzed and calculated by the numerical finite-element analysis methods. The electromagnetic force performances, loss, power factor, and efficiency are also investigated for the asynchronous machine (AM) by using a 2-D finite-element analysis of Ansoft Maxwell. The computational friction model of the AM-WFIG is built to analyze the influence of the viscosity of the ferrofluid. Finally, a prototype of the AM-WFIG is created and tested, and the performance curve of power factor versus speed is acquired to confirm the proposed design. [ABSTRACT FROM AUTHOR]

In this paper, a novel limited swing angle torque permanent magnet motor (LSATPMM) is proposed, and the operating principle of the circuit breaker of the proposed LSATPMM and a mathematical model are analyzed. The characteristics of the high voltage circuit breaker (HVCB) of the proposed machine are analyzed and calculated by numerical finite element analysis methods. The co-simulation of the Maxwell Circuit Editor and Ansoft Maxwell is used to analyze the dynamic characteristics of HVCB. The advantages of the presented operating mechanism for LSATPMM, such as the ability to adjust the opening and closing torque characteristic, high reliability, robust drive system and fault tolerance, are discussed. Finally, a prototype of LSATPMM is created and tested; and the characteristic curve of position versus torque is acquired in order to confirm the proposed design. [ABSTRACT FROM AUTHOR]

Introduction: Patients with mantle cell lymphoma (MCL) frequently develop resistance to ibrutinib. Lymphoma-associated macrophages (LAMs) may play a causal role in this resistance but remain underexplored in current literature., Objectives: To elucidate the role of LAMs in mediating ibrutinib resistance in MCL., Methods: We investigated macrophage polarization through multiparameter flow cytometry (MPFC) using antibodies against CD206 and CD86 in blood and tissue samples from patients with MCL, both resistant and sensitive to ibrutinib. Subsequently, we developed an in vitro co-culture model utilizing MCL cell lines to identify cytokines associated with ibrutinib resistance and macrophage M2 polarization. The mechanisms underlying resistance were examined using MPFC, RNA sequencing, and Western blot analysis. Additionally, we assessed whether SB225002, a CXCR2 inhibitor, could reverse ibrutinib resistance through CCK-8 and caspase-3 assays, as well as in a mouse xenograft model involving an ibrutinib-resistant MCL cell line., Results: In patients exhibiting ibrutinib resistance, the ratio of M2 to M1 LAMs was significantly higher compared to sensitive patients. In co-cultures of LAMs and MCL cells, the percentage of M2 macrophages, the IC50 value for ibrutinib, and the concentrations of IL-8 and CXCL5 were significantly elevated. Mechanistically, CXCL5 secreted by LAMs interacted with the CXCR2 on MCL cells, leading to the activation of the Akt, p38, and STAT3 signaling pathways in the presence of ibrutinib; this activity was diminished upon blockade of the CXCL5/CXCR2 axis. The combination of SB225002 and ibrutinib significantly enhanced MCL cell apoptosis, suppressed lymphoma growth in the xenograft model, and reprogrammed macrophage phenotype compared to treatment with ibrutinib alone., Conclusion: Our data indicate that M2-polarized LAMs are associated with ibrutinib resistance in a model of MCL, and that a CXCR2 inhibitor can reverse this resistance. These findings suggest a potential new therapeutic strategy., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: RPG is a consultant to Antengene Biotech LLC, Ascentage Pharma Group and NexImmune Inc.; Medical Director, FFF Enterprises Inc.; Board of Directors: Russian Foundation for Cancer Research Support; and Scientific Advisory Boards, Nanexa AB and StemRad Ltd., (Copyright © 2024. Production and hosting by Elsevier B.V.)

Background: Immune checkpoint inhibitors (ICIs) induce better tumor regression in melanoma with programmed cell death 1 ligand 1 (PD-L1) high expression, but there has been an upsurge of failed responses. In this study, we aimed to explore the additional mechanisms possibly accounting for ICIs resistance and interventional strategies to overcome the resistance in melanoma with PD-L1 high expression., Methods: Melanoma xenografts and cytotoxicity assays were used to investigate function of SOX2 in regulating antitumor immunity. The activity of the janus kinase-signal transducer and activator of transcriptions (JAK-STAT) pathway was investigated by western blots, quantitative PCR and luciferase assay. Epigenetic compounds library screen was employed to identify inhibitors that could decrease SOX2 level. The effect of histone deacetylase inhibitor SAHA in antitumor immunity alone or in combination with immunotherapy was also determined in vitro and in vivo. Prognostic impact of SOX2 was analyzed using transcriptional profiles and clinical data download from the Gene Expression Omnibus and The Cancer Genome Atlas repository., Results: We uncovered a role of SOX2 in attenuating the sensitivity of melanoma cells to CD8+ T-cell killing. Mechanistically, SOX2 inhibited phosphatases suppressor of cytokine signaling 3 (SOCS3) and protein tyrosine phosphatase non-receptor type 1 (PTPN1) transcription, induced duration activation of the JAK-STAT pathway and thereby overexpression of interferon stimulated genes resistance signature (ISG.RS). By targeting the SOX2-JAK-STAT signaling, SAHA promoted the antitumor efficacy of IFNγ or anti-PD-1 in vitro and in vivo. Moreover, SOX2 was an independent prognostic factor for poor survival and resistant to anti-PD-1 therapy in melanoma with PD-L1 high expression., Conclusions: Our data unveiled an additional function of SOX2 causing immune evasion of CD8+ T-cell killing through alleviating the JAK-STAT pathway and ISG.RS expression. We also provided a rationale to explore a novel combination of ICIs with SAHA clinically, especially in melanoma with PD-L1 and SOX2 high expression., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)