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In this paper, a novel asymmetric trench SiC MOSFET with a Poly-Si/SiC heterojunction diode (HJD-ATMOS) is designed to improve its reverse conduction characteristics and switching performance. This structure features an integrated heterojunction diode, which improves body diode characteristics without affecting device static characteristics. The heterojunction diode acts as a freewheeling diode during reverse conduction, reducing the cut-in voltage (Vcut-in) to a lower level than conventional asymmetric trench SiC MOSFET (C-ATMOS), while maintaining a similar breakdown voltage. Meanwhile, the split gate structure reduces gate-to-drain charge (Qgd). Through TCAD simulation, the HJD-ATMOS decreases Vcut-in by 53.04% compared to the C-ATMOS. Both Qgd and switching loss are reduced, with a decrease of 31.91% in Qgd and 40.29% in switching loss.

MicroRNAs (miRNAs) have been shown to be critical components in plant immunity. MicroRNA398 (miR398) is a highly conserved miRNA in all land plants and plays crucial roles in diverse biotic stress responses. However, the role of miR398 has not yet been characterized in tomato resistance against Botrytis cinerea. In this report, the transcript levels of sly-miR398b were strongly decreased in B. cinerea-infected leaves and the overexpression of sly-miR398b resulted in enhanced susceptibility. The attenuated expression of cytosol Cu/Zn-SOD (CSD1), chloroplast Cu/Zn-SOD (CSD2), and guaiacol peroxidase (GPOD), as well as the decreased activities of superoxide dismutase (SOD) and GPOD, collectively led to increased hydrogen peroxide (H2O2) accumulation in sly-miR398b overexpressing plants. Furthermore, sly-miR398b was induced by methyl jasmonate (MeJA) treatment. The overexpression of sly-miR398b suppressed the expression of TomLoxD, LapA, and PR-STH2 in response to B. cinerea and MeJA treatment. Our data demonstrate that sly-miR398b overexpression negatively regulates the resistance to B. cinerea in tomato by inducing the accumulation of reactive oxygen species (ROS) and downregulating the expression of MeJA-responsive defense genes.

The single-event effect reliability issue is one of the most critical concerns in the context of space applications for SiC VDMOS. In this paper, the SEE characteristics and mechanisms of the proposed deep trench gate superjunction (DTSJ), conventional trench gate superjunction (CTSJ), conventional trench gate (CT), and conventional planar gate (CT) SiC VDMOS are comprehensively analyzed and simulated. Extensive simulations demonstrate the maximum SET current peaks of DTSJ−, CTSJ−, CT−, and CP SiC VDMOS, which are 188 mA, 218 mA, 242 mA, and 255 mA, with a bias voltage VDS of 300 V and LET = 120 MeV·cm2/mg, respectively. The total charges of DTSJ−, CTSJ−, CT−, and CP SiC VDMOS collected at the drain are 320 pC, 1100 pC, 885 pC, and 567 pC, respectively. A definition and calculation of the charge enhancement factor (CEF) are proposed. The CEF values of DTSJ−, CTSJ−, CT−, and CP SiC VDMOS are 43, 160, 117, and 55, respectively. Compared with CTSJ−, CT−, and CP SiC VDMOS, the total charge and CEF of the DTSJ SiC VDMOS are reduced by 70.9%, 62.4%, 43.6% and 73.1%, 63.2%, and 21.8%, respectively. The maximum SET lattice temperature of the DTSJ SiC VDMOS is less than 2823 K under the wide operating conditions of a drain bias voltage VDS ranging from 100 V to 1100 V and a LET value ranging from 1 MeV·cm2/mg to 120 MeV·cm2/mg, while the maximum SET lattice temperatures of the other three SiC VDMOS significantly exceed 3100 K. The SEGR LET thresholds of DTSJ−, CTSJ−, CT−, and CP SiC VDMOS are approximately 100 MeV·cm2/mg, 15 MeV·cm2/mg, 15 MeV·cm2/mg, and 60 MeV·cm2/mg, respectively, while the value of VDS = 1100 V.

Single-event gate-rupture (SEGR) in the trench vertical double-diffused power MOSFET (VDMOS) occurs at a critical bias voltage during heavy-ion experiments. Fault analysis demonstrates that the hot spot is located at the termination of the VDMOS, and the gate oxide in the termination region has been damaged. The SEGR-hardened termination with multiple implantation regions is proposed and simulated using the Sentaurus TCAD. The multiple implantation regions are introduced, leading to an increase in the distance between the gate oxide and the hole accumulation region, as well as a decrease in the resistivity of the hole conductive path. This approach is effective in reducing the electric field of the gate oxide to below the calculated critical field, and results in a lower electric field than the conventional termination.

Abstract Many active volcanoes and various types of seismic activities exist in the southern part of the Northeast Japan subduction zone. One of the geologically most interesting features in this area is the sequential explosive eruptions of a group of volcanoes. The group consists of Mt. Azuma and Mt. Adatara on the volcanic front line, Mt. Bandai west of the volcanic front, and Mt. Numazawa on the back-arc side. A previous petrological study on the eruption products regarded Mt. Numazawa as an anomalous back-arc volcano because its lavas are similar to those of volcanoes on the volcanic front. The reason behind this unique connection was unclear, and hence, this study was intended to understand the deep fluids distribution beneath the area. For this purpose, a 3-D regional electrical resistivity structure was estimated from a series of wide-band magnetotelluric surveys, with 45 observation points deployed from the fore-arc to the back-arc sides. The most important feature of the resistivity structure is a large conductive zone in the central part of the area, spanning from the upper mantle to the lower crust. Interestingly, the lateral elongation of the conductor is oblique to the volcanic front line and consistent with the spatial distribution of the group of volcanoes and the low-frequency earthquake clusters around them. Therefore, the conductor most likely represents a large, elongated magmatic fluid reservoir beneath the volcanoes. Hydrous partial melting might be the cause of the enhanced conductivity. Graphical Abstract

Curcumin, the primary bioactive substance in turmeric, is known to be associated with weight loss. In this study, we employed Caenorhabditis elegans, a well-established in vivo nematode model to explore the role of curcumin in regulating lipid metabolism. C. elegans administrated with curcumin (10, 25 and 50 μM) exhibited significantly reduced fat accumulation, along with smaller body size (width) when compared to the control, without significantly affecting the feeding behavior. Locomotive activity (average moving speed) was significantly increased by curcumin treatment, suggesting a potential increase in energy expenditure. The reduced fat accumulation by curcumin was dependent on lipogenesis-associated genes, sbp-1 (encodes the homolog of sterol response element binding proteins) and fat-6 (encodes a homolog of stearoyl-CoA desaturase), as curcumin significantly down-regulated the expression levels of these two genes and its fat reduction effect was nulled by the mutation of sbp-1 and fat-6. Additionally, the increased locomotive activity by curcumin was dependent on sbp-1. Current results suggest that curcumin decreases fat accumulation by inhibiting sbp-1/fat-6-mediated signaling in Caenorhabditis elegans.

Caenorhabditis elegans, a free-living nematode, is an animal model that has been extensively employed in a variety of research fields, including in the study of obesity. Its favorable features include its compact size, short life cycle, large brood size, easy handling, low cost, availability of complete genetic information, 65% conserved human diseases-associated genes, relatively easy genetic manipulation, and research using Caenorhabditis elegans does not require approvals by the Institutional Animal Care and Use Committee. These advantages make Caenorhabditis elegans a great in vivo model for life science research including obesity research. In this review, we provide graphic overviews of Caenorhabditis elegans’ basic anatomy, growth conditions, routes of compound delivery, and fat metabolism, both synthesis and degradation pathways, including major signaling pathways involved. Our aim is to provide an overview for researchers interested in applying C. elegans as an in vivo model for the screening and identification of anti-obesity bioactive compounds prior to testing in vertebrate animal models.

Isorhamnetin (3-O-methylquercetin), a flavonol found in dill weed, sea buckthorn berries, kale and onions, has been suggested to have anti-obesity effects, but there is limited evidence of its mechanisms of action on lipid metabolism. The goal of this study was to investigate the effects of isorhamnetin on lipid metabolism using Caenorhabditis elegans as an animal model. Isorhamnetin reduced fat accumulation without affecting food intake or energy expenditure in C. elegans. The isorhamnetin's fat-lowering effects were dependent on nhr-49, a homolog of the human peroxisome proliferator-activated receptor alpha (PPARα). Isorhamnetin upregulated an enoyl-CoA hydratase (ech-1.1, involved in fatty acid β-oxidation) and adipose triglyceride lipase (atgl-1, involved in lipolysis) via NHR-49-dependent pathway at transcriptional levels. Isorhamnetin also upregulated the C. elegans AMP-activated protein kinase (AMPK) subunits homologs (aak-1 and aak-2), involved in energy homeostasis. These results suggest that isorhamnetin reduces body fat by increasing fat oxidation in part via NHR-49/PPARα-dependent pathway.