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In order to cope with the grid fluctuation caused by large‐scale wind power connected to the grid, the wind thermal power generation system has been proposed and extensively studied. The wind thermal power generation system uses a wind turbine to drive a heat generation device to heat the heat storage medium, which is further exchanged to drive a turbine to generate electricity. A superconducting magnetic eddy current heater (SMH) is proposed for the characteristics of wind thermal power generation system, which uses non‐resistive, large current‐carrying superconducting coils for excitation, and has high output efficiency and power density. The working principle of magnetic eddy current heating is analysed, and the structure of SMH with no ferromagnetic material and two heating screens inside and outside is proposed according to the characteristics of SMH. An analytical model of the SMH is established, and the influence of the structure and materials of the SMH on the magnetic field distribution is analysed. Based on this, a 22‐pole SMH was designed and analysed for output power at 10–20 rpm. A three‐dimensional magnetism‐stress combined analysis model of SMH is established, and the strain and stress characteristics of SMH are simulated under the condition of maximum output power, which verifies the feasibility of the mechanical properties of existing superconducting materials for application in SMH. [ABSTRACT FROM AUTHOR]

Summary: More than half of the world's food is provided by cereals, as humans obtain >60% of daily calories from grains. Producing more carbohydrates is always the final target of crop cultivation. The carbohydrate partitioning pathway directly affects grain yield, but the molecular mechanisms and biological functions are poorly understood, including rice (Oryza sativa L.), one of the most important food sources. Here, we reported a prolonged grain filling duration mutant 1 (gfd1), exhibiting a long grain‐filling duration, less grain number per panicle and bigger grain size without changing grain weight. Map‐based cloning and molecular biological analyses revealed that GFD1 encoded a MATE transporter and expressed high in vascular tissues of the stem, spikelet hulls and rachilla, but low in the leaf, controlling carbohydrate partitioning in the stem and grain but not in the leaf. GFD1 protein was partially localized on the plasma membrane and in the Golgi apparatus, and was finally verified to interact with two sugar transporters, OsSWEET4 and OsSUT2. Genetic analyses showed that GFD1 might control grain‐filling duration through OsSWEET4, adjust grain size with OsSUT2 and synergistically modulate grain number per panicle with both OsSUT2 and OsSWEET4. Together, our work proved that the three transporters, which are all initially classified in the major facilitator superfamily family, could control starch storage in both the primary sink (grain) and temporary sink (stem), and affect carbohydrate partitioning in the whole plant through physical interaction, giving a new vision of sugar transporter interactome and providing a tool for rice yield improvement. [ABSTRACT FROM AUTHOR]

The combination of semiconductivity and tunable ferromagnetism is pivotal for electrical control of ferromagnetism and next‐generation low‐power spintronic devices. However, Curie temperatures (TC) for most traditional intrinsic ferromagnetic semiconductors (≤200 K) and recently discovered two‐dimensional (2D) ones (<70 K) are far below room temperature. 2D van der Waals (vdW) semiconductors with intrinsic room‐temperature ferromagnetism remain elusive considering the unfavored 2D long‐range ferromagnetic order indicated by Mermin–Wagner theorem. Here, vdW semiconductor CrxGa1−xTe crystals exhibiting highly tunable above‐room‐temperature ferromagnetism with bandgap 1.62–1.66 eV are reported. The saturation magnetic moment (Msat) of CrxGa1−xTe crystals can be effectively regulated up to ≈5.4 times by tuning Cr content and ≈75.9 times by changing the thickness. vdW CrxGa1−xTe ultrathin semiconductor crystals show robust room‐temperature ferromagnetism with the 2D quantum confinement effect, enabling TC 314.9–329 K for nanosheets, record‐high for intrinsic vdW 2D ferromagnetic semiconductors. This work opens an avenue to room‐temperature 2D vdW ferromagnetic semiconductor for 2D electronic and spintronic devices. [ABSTRACT FROM AUTHOR]

In the past decade, metal‐halide perovskites have attracted increasing attention in optoelectronics, due to their superior optoelectronic properties. However, inherent instabilities of conventional three‐dimensional (3D) perovskites over moisture, heat, and light remain a severe challenge before the realization of commercial application of metal‐halide perovskites. Interestingly, when the dimensions of metal‐halide perovskites are reduced to two dimensions (2D), many of the novel properties will arise, such as enlarged bandgap, high photoluminescence quantum yield, and large exciton binding energy. As a result, 2D metal‐halide perovskite‐based optoelectronic devices display excellent performance, particularly as ambient stable solar cells with excellent power conversion efficiency (PCE), high‐performance light‐emitting diodes (LEDs) with sharp emission peak, and high‐sensitive photodetectors. In this review, we first introduce the synthesis, structure, and physical properties of 2D perovskites. Then, the 2D perovskite‐based solar cells, LEDs, and photodetectors are discussed. Finally, a brief overview of the opportunities and challenges for 2D perovskite optoelectronics is presented. [ABSTRACT FROM AUTHOR]

Aims: We previously showed that the protective effects of endothelial progenitor cells (EPCs)‐released exosomes (EPC‐EXs) on endothelium in diabetes. However, whether EPC‐EXs are protective in diabetic ischemic stroke is unknown. Here, we investigated the effects of EPC‐EXs on diabetic stroke mice and tested whether miR‐126 enriched EPC‐EXs (EPC‐EXsmiR126) have enhanced efficacy. Methods: The db/db mice subjected to ischemic stroke were intravenously administrated with EPC‐EXs 2 hours after ischemic stroke. The infarct volume, cerebral microvascular density (MVD), cerebral blood flow (CBF), neurological function, angiogenesis and neurogenesis, and levels of cleaved caspase‐3, miR‐126, and VEGFR2 were measured on day 2 and 14. Results: We found that (a) injected EPC‐EXs merged with brain endothelial cells, neurons, astrocytes, and microglia in the peri‐infarct area; (b) EPC‐EXsmiR126 were more effective than EPC‐EXs in decreasing infarct size and increasing CBF and MVD, and in promoting angiogenesis and neurogenesis as well as neurological functional recovery; (c) These effects were accompanied with downregulated cleaved caspase‐3 on day 2 and vascular endothelial growth factor receptor 2 (VEGFR2) upregulation till day 14. Conclusion: Our results indicate that enrichment of miR126 enhanced the therapeutic efficacy of EPC‐EXs on diabetic ischemic stroke by attenuating acute injury and promoting neurological function recovery. [ABSTRACT FROM AUTHOR]

Abstract: The Weyl semimetal WTe2 and MoTe2 show great potential in generating large spin currents since they possess topologically protected spin‐polarized states and can carry a very large current density. In addition, the intrinsic non‐centrosymmetry of WTe2 and MoTe2 endows with a unique property of crystal symmetry‐controlled spin–orbit torques. An important question to be answered for developing spintronic devices is how spins relax in WTe2 and MoTe2. Here, a room‐temperature spin relaxation time of 1.2 ns (0.4 ns) in WTe2 (MoTe2) thin film using the time‐resolved Kerr rotation (TRKR) is reported. Based on ab initio calculation, a mechanism of long‐lived spin polarization resulting from a large spin splitting around the bottom of the conduction band, low electron–hole recombination rate, and suppression of backscattering required by time‐reversal and lattice symmetry operation is identified. In addition, it is found that the spin polarization is firmly pinned along the strong internal out‐of‐plane magnetic field induced by large spin splitting. This work provides an insight into the physical origin of long‐lived spin polarization in Weyl semimetals, which could be useful to manipulate spins for a long time at room temperature. [ABSTRACT FROM AUTHOR]

Objectives: The non‐canonical inflammasome pathway was described which engages caspase‐11 to mediate pyroptosis and the subsequent release of IL‐1α, IL‐1β and IL‐18 in TLR4‐independent way. Cathepsin B is capable of activating caspase‐11 under cell‐free conditions which may regulate non‐canonical NLRP3 inflammasome pathway. In this study, we aimed to further investigate cathepsin B as potential activators of proinflammatory caspases which may be released upon proinflammatory stimuli and regulate non‐canonical NLRP3 inflammasome pathway by modulating the activity of caspase‐11. Methods: Pharmacological and gene‐silencing approaches were used to evaluate the impact of cathepsin B on regulating non‐canonical NLRP3 inflammasome pathway in wild‐type and TLR4–/– Kupffer cells. A sepsis model was also created to investigate the effect of cathepsin B on survival. Meanwhile, cathepsin B activity and the expression level of caspase‐4 were detected in human peripheral blood mononuclear cells (PBMC) which were separated from patients suffered from SIRS or sepsis and healthy volunteers. Results: LPS stimulation caused cathepsin B activity and caspase‐11 expression increase in TLR4–/– mice. Cathepsin B activity inhibition reduced the activation of caspase‐11 and inflammasome and benefited survival in TLR4–/– mice. Upregulation of cathepsin B activity and caspase‐4 activation was found in PBMC of patients with SIRS or sepsis. Conclusion: Our results suggest a critical role for cathepsin B as activators of proinflammatory caspases‐11 and the regulatory effect in LPS‐induced caspases‐11‐dependent necrosis. [ABSTRACT FROM AUTHOR]

Angiotensin (Ang) AT1 receptors and Ang-converting enzymes (ACE and ACE2) are expressed in the dorsal vagal complex (DVC) of the brainstem. The aim of this study was to examine in vivo interactions between brainstem Ang AT1 receptors, ACE and ACE2 using small, hairpin RNA (shRNA) gene-silencing methods. The study takes advantage of the bilateral brainstem expression of renin-angiotensin system (RAS) markers. Adenovirus vectors (Ad, 2.0 x 10(9) c.f.u. ml(-1), 200 nl) carrying interference small hairpin RNA (shRNA) for either AngAT1a (Ad-AT1a-shRNA) or AngAT1b (Ad-AT1b-shRNA) were microinjected into the right side of the brainstem DVC. The Ad-LacZ control was injected into the left side. Brainstems were processed with in situ hybridization and immunochemistry. Results showed that: (1) Ad-AT1a-shRNA downregulated Ang AT1a mRNA by 61.2 +/- 6.8% (P < 0.01) and Ad-AT1b-shRNA downregulated Ang AT1b mRNA by 51.6 +/- 5.2% (P < 0.01); (2) downregulation of Ang AT1a mRNA was associated with decreased ACE2 mRNA expression (decrease of 29.0 +/- 14.5%, P < 0.01), while reduction in Ang Ad-AT1b mRNA had no effect; (3) ACE mRNA expression was not altered by either RNA interference (RNAi) treatment; and (4) immunochemical staining for Ang AT1 receptors, ACE and ACE2 were in agreement with the mRNA changes observed. These results demonstrate the utility of in vivo gene silencing to examine functional specificity. Both Ad-AT1a-shRNA and Ad-AT1b-shRNA induced site- and subtype-specific downregulation of receptor expression. Gene silencing showed that there were interactions between brainstem Ang AT1a receptors and the RAS regulatory enzyme, ACE2.