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We present a new device called a common-mode impedance stabilizing device (CMISD), which is applied to the output of inverters installed in railroad vehicles. The proposed device is used in the evaluation of the disturbance voltage in conductive emissions; its purpose is to stabilize the common-mode (CM) impedance ( $150~\pm ~20~\Omega $ ) in the 100 kHz – 10 MHz frequency range, which corresponds to the operating frequencies of railroad signaling devices called “balises.” The balises are installed on railroad tracks and used for communication between trains and wayside systems, and electromagnetic compatibility between rolling stock and the balises are severe problem. In the design of the CMISD, we considered two factors: the ferrite core size of the CM inductor and the heat dissipation in the resistors. In the CM inductor, we assumed realistic conditions to reduce its core mass to ~3.4 kg. Regarding heat dissipation, considering that the negative terminal of a railroad vehicle with DC feeding voltage must be grounded, we assumed that square-wave peak voltage is applied directly to the CM circuit of the CMISD. The experimental results showed that the power dissipation in the CR series circuit in the CMISD was proportional to the carrier frequency, capacitance, and the square of the line voltage. Eventually, we fabricated a prototype CMISD, which can withstand the heat generated when applying a 750-V DC input voltage at a 3-kHz carrier frequency for five minutes.

Double-stranded RNA (dsRNA) is a molecular pattern uniquely produced in cells infected with various viruses as a product or byproduct of replication. Cells detect such molecules, which indicate non-self invasion, and induce diverse immune responses to eliminate them. The degradation of virus-derived molecules can also play a role in the removal of pathogens and suppression of their replication. RNautophagy and DNautophagy are cellular degradative pathways in which RNA and DNA are directly imported into a hydrolytic organelle, the lysosome. Two lysosomal membrane proteins, SIDT2 and LAMP2C, mediate nucleic acid uptake via this pathway. Here, we showed that the expression of both SIDT2 and LAMP2C is selectively upregulated during the intracellular detection of poly(I:C), a synthetic analog of dsRNA that mimics viral infection. The upregulation of these two gene products upon poly(I:C) introduction was transient and synchronized. We also observed that the induction of SIDT2 and LAMP2C expression by poly(I:C) was dependent on MDA5, a cytoplasmic innate immune receptor that directly recognizes poly(I:C) and induces various antiviral responses. Finally, we showed that lysosomes can target viral RNA for degradation via RNautophagy and may suppress viral replication. Our results revealed a novel degradative pathway in cells as a downstream component of the innate immune response and provided evidence suggesting that the degradation of viral nucleic acids via RNautophagy/DNautophagy contributes to the suppression of viral replication.

Abstract The abnormal aggregation of TDP-43 into cytoplasmic inclusions in affected neurons is a major pathological hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Although TDP-43 is aberrantly accumulated in the neurons of most patients with sporadic ALS/FTD and other TDP-43 proteinopathies, how TDP-43 forms cytoplasmic aggregates remains unknown. In this study, we show that a deficiency in DCTN1, a subunit of the microtubule-associated motor protein complex dynactin, perturbs the dynamics of stress granules and drives the formation of TDP-43 cytoplasmic aggregation in cultured cells, leading to the exacerbation of TDP-43 pathology and neurodegeneration in vivo. We demonstrated using a Drosophila model of ALS/FTD that genetic knockdown of DCTN1 accelerates the formation of ubiquitin-positive cytoplasmic inclusions of TDP-43. Knockdown of components of other microtubule-associated motor protein complexes, including dynein and kinesin, also increased the formation of TDP-43 inclusions, indicating that intracellular transport along microtubules plays a key role in TDP-43 pathology. Notably, DCTN1 knockdown delayed the disassembly of stress granules in stressed cells, leading to an increase in the formation of pathological cytoplasmic inclusions of TDP-43. Our results indicate that a deficiency in DCTN1, as well as disruption of intracellular transport along microtubules, is a modifier that drives the formation of TDP-43 pathology through the dysregulation of stress granule dynamics.

This paper proposes a solid-state circuit breaker comprising silicon carbide (SiC) MOSFETs and a SiC diode, based on the principle of avalanche voltage clamping. The key challenge in realizing a solid-state circuit breaker lies in reducing conduction loss. A parallel connection of power semiconductor devices is the suitable configuration that can meet these requirements. However, in such a configuration, the current balance during cutoff operation may be affected by the variation in the breakdown voltage characteristics of the power semiconductor devices. To address this issue, the proposed circuit breaker employs clamping with a SiC merged pin Schottky (MPS) diode, with high avalanche tolerance and robust characteristics under repetitive avalanche events. The effectiveness of the proposed solid-state circuit breaker is validated through experiments conducted in an unclamped inductive switching (UIS) test circuit using a 400-V, 50-A DC distribution system. Eventually, the demonstrations indicate that the SiC diode clamping method contributes to more compact implementations for solid-state circuit breakers.

Modern electric railway vehicles are faced with the challenge of achieving electromagnetic compatibility (EMC) compliance with railway signaling systems. Currently, no established countermeasures or design methods that guarantee passing the EMC compliance test are available. Therefore, the enhancement of EMC management during vehicle manufacturing processes is imperative. This study devised a pre-accreditation method to be implemented at the vehicle completion stage, prior to the EMC compliance test. The proposed method entails the substitution of real ground signaling devices, whose parameters are difficult to obtain, with unified coils. The effectiveness of this approach is validated by observing whether the gain difference remains consistent when using both an exciting coil and a test train. To illustrate this method, we selected the platform screen door (PSD) balise as a representative signaling device, which is widely utilized in various railway stations. The unified coil employed in this study can be easily fabricated. First, we measured the gain difference (the ratio between the induced voltage of coils and the exciting coil current) between the PSD balise and unified coil. Next, we measured the unknown magnetic flux induced by an 8-car electric multiple unit test train by utilizing the PSD balise and unified coil. Finally, we calculated the measured difference between them. The gain and measured differences properly agreed (within 6 dB) across a wide frequency range of 200 kHz to 4 MHz.

This paper proposes a gate drive circuit with a condition monitoring function for detecting the gate oxide degradation in silicon carbide (SiC) metal–oxide–semiconductor field-effect transistors (MOSFETs). Trapped charges in the gate oxide can cause fluctuations in the on-resistance and gate threshold voltages. These phenomena affect the long-term reliability of power conversion circuits. The proposed condition monitoring function detects the degradation of the gate oxide by measuring the input capacitance $C_{\mathrm{iss}}$ versus the gate–source voltage $v_{\mathrm{GS}}$ characteristics ($C_{\mathrm{iss}}$–$v_{\mathrm{GS}}$ characteristics) of SiC MOSFETs implemented in power conversion circuits. Experiments on the proposed gate drive circuit were conducted using a 400 W-rated buck converter circuit in which a SiC MOSFET is implemented. The experimental results show that the gate drive circuit is capable of online measurement of $C_{\mathrm{iss}}$–$v_{\mathrm{GS}}$ characteristics and gate drive at 20 kHz. The online measurement of the $C_{\mathrm{iss}}$–$v_{\mathrm{GS}}$ characteristics corresponds to the offline measurement with a measurement instrument, indicating the effectiveness of the gate drive circuit.

In the traction system of rolling stock, the common-mode (CM) voltage is over 500 V, so the inductors that suppress the CM current are prone to saturation. To prevent saturation, the traction inverter needs many numbers of cores inside CM inductors, but the required number of cores has been determined empirically. This paper proposes a method calculate the approximate number of nanocrystalline cores to avoid saturation of CM inductors in railway traction inverters without circuit simulation. Using the only the CM capacitance of traction motor and the core characteristics on the datasheet, the maximum flux density of the inductor is calculated. Comparing calculated results of the maximum flux density with the results measured with a 1500 V DC inverter indicates that the proposed method can better identify the occurrence of saturation than the methods based on CM current presented in the literature. Furthermore, for the entire CM voltage range from 500 V to 3000 V, the minimum number of cores which saturation is prevented by the proposed calculation method is shown to be in reasonable agreement with the simulation results.

The development of SiC and GaN power devices to achieve high-speed switching operations in power converter circuits is underway. The stray inductance caused by the bus bar geometries between DC capacitors and power devices influences high-speed switching circuits, such as surge voltages and switching losses. Therefore, the evaluation of the parasitic parameters is essential in designing power converter circuits. Currently, parasitic parameters that consider various bus bar geometries are calculated using finite element analysis (FEA) each time, which requires a large calculation time. This article proposes a prediction procedure for the parasitic parameters that easily and quickly consider complex bus bar geometries by performing online machine learning of FEA-based datasets. A laminated bus bar with two apertures to connect DC capacitors or power modules is analyzed, and the parasitic resistance, inductance, and capacitance are predicted. This article describes how large datasets can be obtained from multiple installments and perform online machine learning using XGBoost. To discuss the benefits of online machine learning, the prediction accuracy using test data in multiple machine learning models with different amounts of training data is compared. The mean relative error (MRE) between the predicted and analyzed values improves from 250% to 8% when parasitic parameters are predicted in the frequency range of 50 kHz to 100 MHz.

This article proposes an improved overvoltage suppression method for the initial charge of the dc capacitor in voltage source power converters. The proposed method makes multiple short-circuits in each leg, utilizing power devices in the converter. These short-circuits discharge the dc capacitor and suppress overvoltage caused by resonant effects during the initial charge. The utilization of short durations of short-circuits multiple times in each leg reduces the power consumption in the power devices and results in a decrease in the peak junction temperature. Experimental verification using a 200-V, 5-kVA three-phase converter demonstrates that the proposed multiple short-circuit method reduces power consumption by 6% and suppresses device degradation by more than 40 times compared to the previously proposed single short-circuit method. The experimental results exhibit the effective overvoltage suppression capability of the proposed method with modest device degradation. As a result, the proposed method allows for the elimination of the initial charge circuit, leading to reductions in the size and cost of power converters, particularly in PWM rectifiers.

Abnormal expansions of GGGGCC repeat sequence in the noncoding region of the C9orf72 gene is the most common cause of familial amyotrophic lateral sclerosis and frontotemporal dementia (C9-ALS/FTD). The expanded repeat sequence is translated into dipeptide repeat proteins (DPRs) by noncanonical repeat-associated non-AUG (RAN) translation. Since DPRs play central roles in the pathogenesis of C9-ALS/FTD, we here investigate the regulatory mechanisms of RAN translation, focusing on the effects of RNA-binding proteins (RBPs) targeting GGGGCC repeat RNAs. Using C9-ALS/FTD model flies, we demonstrated that the ALS/FTD-linked RBP FUS suppresses RAN translation and neurodegeneration in an RNA-binding activity-dependent manner. Moreover, we found that FUS directly binds to and modulates the G-quadruplex structure of GGGGCC repeat RNA as an RNA chaperone, resulting in the suppression of RAN translation in vitro. These results reveal a previously unrecognized regulatory mechanism of RAN translation by G-quadruplex-targeting RBPs, providing therapeutic insights for C9-ALS/FTD and other repeat expansion diseases.

Introduction: Spine surgery is challenging in hemodialysis (HD)-dependent patients owing to their poor general condition. However, postoperative complications and the mortality and survival rates have not been specifically evaluated in a wide series. This study aimed to elucidate postoperative complications and the survival rate in cervical spine surgery in HD patients. Methods: This study included 109 HD patients (70 men, 39 women) who had undergone cervical spine surgery between July 1996 and May 2018. Based on radiological diagnosis, we divided them into the destructive spondyloarthropathy (DSA) and non-DSA groups. We investigated the causes of hemodialysis, postoperative complications, postoperative inpatient mortality rate, and survival rate. Results: The DSA and non-DSA groups included 100 surgeries in 89 patients and 21 surgeries in 20 patients, respectively. The mean age at surgery was 62.9 years for the DSA and 55.9 years for the non-DSA group (P=0.97). The DSA group had a shorter hemodialysis period at surgery compared with the non-DSA group (21.7 vs. 26.5 years, P0.05). However, significantly low survival rates were observed in HD caused by diabetes compared with that by chronic glomerulonephritis (P

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused the pandemic of the coronavirus disease 2019 (COVID-19), resulting in a global lockdown in 2020. This stagnation in human activities ('anthropause') has been reported to affect the behaviour of wildlife in various ways. The sika deer Cervus nippon in Nara Park, central Japan, has had a unique relationship with humans, especially tourists, in which the deer bow to receive food and sometimes attack if they do not receive it. We investigated how a decrease and subsequent increase in the number of tourists visiting Nara Park affects the number of deer observed in the park and their behaviour (bows and attacks against humans). Compared with the pre-pandemic years, the number of deer in the study site decreased from an average of 167 deer in 2019 to 65 (39%) in 2020 during the pandemic period. Likewise, the number of deer bows decreased from 10.2 per deer in 2016-2017 to 6.4 (62%) in 2020-2021, whereas the proportion of deer showing aggressive behaviour did not change significantly. Moreover, the monthly numbers of deer and their bows both corresponded with the fluctuation in the number of tourists during the pandemic period of 2020 and 2021, whereas the number of attacks did not. Thus, the anthropause caused by the coronavirus altered the habitat use and behaviour of deer that have continuous interactions with humans.

Background: his study aimed to clarify the quantitative threshold of intraoperative radiological parameters for suspecting posterior malposition of the oblique lumbar interbody fusion (LF) cage triggering contralateral radiculopathy. Methods: We measured the sagittal center and axial rotation angle () of the cage using postoperative computed tomography () in 130 patients (215 cages) who underwent LF. he location of the cage tip was determined from axial magnetic resonance imaging in selected cases based on simulations to assess whether the cage was in contact with the contralateral exiting nerve or whether the surgical instruments could contact the nerve during intradiscal maneuvers. Results: he sagittal center of the cages was on average 41.5% from the anterior edge of the endplate (shown as / P value: anterior end plate edge-cage center/anterior-posterior endplate edge ×100%), and posterior cage positioning ≥50% occurred in 14% of the cages. he was -2.9°, and posterior oblique rotation of the cages ≥10° ( ≤ -10°) was observed in 13%. simulation showed that the cage tip could directly contact the contralateral nerve when the cage was placed deep in the posterior portion ≥50% of the /P values with concomitant posterior axial rotation ≥10° ( ≤ -10°), or deep in an extremely rare portion ≥60% of the /P values with posterior axial rotation ≥0° ( ≤ 0°). Six percent of the cages (13/215) were placed in these posterior oblique areas (potential contact area: P). hree cages in the P were in direct contact with the contralateral nerves, and 9 were placed deep just anterior to the nerves. Symptomatic contralateral radiculopathy occurred in 2 cages (2/13/215, 15.3%/0.9%). Conclusions: wo intraoperative radiological parameters (/P and ) measurable during LF procedures may become practical indicators for suspecting cage malposition in P and may be available when determining whether to consider cage revision intraoperatively to a more ventral disc space or anteriorly from the opposite endplate edge. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

Research data on the biological effects of intermediate-frequency magnetic fields (IF-MF) remain inadequate, and there are no protocols currently exists that can assess the biological effects of electromagnetic fields similar to those used with the OECD guidelines for chemicals. IF-MF <100 kHz have a dominant stimulatory effect, which has raised concerns about their effects on neurological disorders. The purpose of this study was to investigate methods for detecting pain in response to IF-MF exposure and to establish a standardized protocol for electromagnetic field pain assessment for use in various environments. The von Frey test, which can assess foot pain, was performed using the partial sciatic nerve ligation (PSL) model, which is a nerve hypersensitivity and allodynia model, together with IF-MF-exposed, sham-exposed, and no-treatment (control) groups. Significant changes were observed at all postoperative measurement points in the PSL group, whereas no significant differences were present among the other groups. In addition, gene expression analysis for four inflammation-related factors (P2rx4, Ccl2, Irf8, and Iba1) was performed using real-time quantitative PCR in the sciatic nerve on postoperative day 15 after exposure. The expression of these genes was significantly upregulated in the PSL group but was unchanged in the remaining three groups. These results confirm that IF-MF exposure (1 hr/day), which is 2.3 times higher than the basic restriction for occupational exposure according to the ICNIRP guidelines, does not cause pain and that these detection methods with positive controls are effective as pain assessment methods for IF-MF exposure. [ABSTRACT FROM AUTHOR]