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Purpose: During Japan's initial pandemic prevention and control period, the Ministry of Education, Culture, Sports, Science, and Technology of Japan (MEXT) issued several notifications to ensure students' continuous learning according to the "leave no one behind" philosophy. This study focused on the comprehensive measures comprising top-level arrangements to implement the "suspending classes without stopping learning" initiative. Design/Approach/Methods: The study reviewed MEXT's guide on ensuring learning for Japanese primary and secondary school students during the pandemic. Findings: The pandemic has accelerated the development of the information and communications technology educational environment and the implementation of the Global and Innovation Gateway for All (GIGA) schools initiative. These developments laid the foundation for the evolution of diverse pedagogical models and feasible methods for promoting equity. The home schooling experience during the pandemic provided a natural base for students to practice and foster survivability. Originality/Value: This paper provides scholars with an understanding of the opportunities and challenges encountered in educational innovation in Japan. It provides insights into the future direction of pedagogical development, capability development, and effective educational arrangements for extraordinary circumstances to facilitate educational development from a broader perspective, particularly under the new normal.

In this paper, we propose a novel three-dimensional-printed Luneburg lens for converting linear polarization to dual-circular polarization and successfully apply it in a multibeam antenna. The discrete unit cell, used as the gradient-index material to approximate the required refractive index in the Luneburg lens, has its effective refractive index calculated by effective medium theory. To achieve the polarization conversion, the symmetry of the unit cell is disrupted. A 100 mm diameter lens is designed to operate at 12.6-17.1 GHz, fed by a low-profile dual-polarized magneto-electric dipole antenna. By analyzing the size and isolation of the antenna, a multibeam lens antenna with five feeds was designed, which features a compact antenna layout and low coupling between them. The multibeam Luneburg lens antenna enables beam scanning of ±60° in the horizontal plane. Measurement results show an overlapped bandwidth of 30% with reflection coefficients below -10 dB and axial ratios under 3 dB. At the center frequency of 15 GHz, the gain reaches 21 dBi, approximately 14 dB higher than the magneto-electric dipole antenna without the lens.

Abstract The in-plane-magnetic-field-induced Hall effect (IPHE) observed in Weyl semimetals and PT-symmetric antiferromagnets has attracted increasing attention, as it breaks the stereotype that the Hall effect is induced by an out-of-plane magnetic field or magnetization. To date, the IPHE has been discussed mainly for materials with low-symmetry crystal/magnetic point groups. Here, we show that even if symmetry forbids an inherent IPHE that arises from any mechanism, an apparent IPHE can be generated by selecting a low-symmetry crystalline plane for measurement. For rutile RuO2, although its high symmetry forbids an inherent IPHE, films grown along the low-symmetry (1 1 1) and (1 0 1) orientations are found to exhibit a distinct IPHE. The in-plane Hall coefficients are quantitatively reproduced by referring to the out-of-plane Hall coefficients measured for the high-symmetry (1 0 0) and (0 0 1) planes, indicating that the observed IPHE is caused by a superposition of inequivalent out-of-plane Hall effects. Similar behaviour is also observed for paramagnetic rutile systems, indicating the ubiquity of the apparent IPHE in electronic and spintronic devices with low-symmetry crystalline planes.

Abstract Strong light-matter interaction provides opportunities for tailoring the physical properties of quantum materials on the ultrafast timescale by forming photon-dressed electronic states, i.e., Floquet-Bloch states. While the light field can in principle imprint its symmetry properties onto the photon-dressed electronic states, so far, how to experimentally detect and further engineer the symmetry of photon-dressed electronic states remains elusive. Here by utilizing time- and angle-resolved photoemission spectroscopy (TrARPES) with polarization-dependent study, we directly visualize the parity symmetry of Floquet-Bloch states in black phosphorus. The photon-dressed sideband exhibits opposite photoemission intensity to the valence band at the Γ point, suggesting a switch of the parity induced by the light field. Moreover, a “hot spot” with strong intensity confined near Γ is observed, indicating a momentum-dependent modulation beyond the parity switch. Combining with theoretical calculations, we reveal the light-induced engineering of the wave function of the Floquet-Bloch states as a result of the hybridization between the conduction and valence bands with opposite parities, and show that the “hot spot” is intrinsically dictated by the symmetry properties of black phosphorus. Our work suggests TrARPES as a direct probe for the parity of the photon-dressed electronic states with energy- and momentum-resolved information, providing an example for engineering the wave function and symmetry of such photon-dressed electronic states via Floquet engineering.

Background: Light at night (LAN) has become a global concern. However, little is known about the effects of bedroom LAN exposure on glucose metabolism markers. We aimed to explore the association between intensity and duration of bedroom LAN exposure with glucose metabolism markers, and the role of circadian-dependent meal timing in these associations. Methods: Real-ambient bedroom LAN exposure was measured using a portable illuminance meter for two consecutive days. Seven consecutive days of sleep time and 24-h dietary records were assessed by wrist-worn accelerometer and mobile phone photos, respectively. Circadian-dependent meal timing, including the timing of meal relative to clock time and sleep time, was calculated from 24-h dietary records and sleep data. Results: The mean age of participants was 18.7 years, and 32.8 % were male. Per SD lx increase of bedroom LANavg was associated with 1.75 μU/mL-increase in INS (95 %CI: 0.10, 2.50), 0.61 unit-increase in HOMA-IR (95 %CI: 0.43, 0.79), and 0.09 unit-increase in TyG (95 %CI: 0.04, 0.15); per SD min increase of bedroom LAN3 was associated with 1.61 μU/mL-increase in INS (95 %CI: 0.84, 2.37), 0.48 unit-increase in HOMA-IR (95 %CI: 0.29, 0.67), and 0.07 unit-increase in TyG (95 %CI: 0.01, 0.13). Nevertheless, these associations were found to be significant in later circadian-dependent meal timing group while weaker or not significant in earlier circadian-dependent meal timing group (time of first meal ≤ 9:00, time of last meal ≤ 19:00, first meal - sleep end ≤ 2 h, and sleep onset - last meal ≥ 5 h). Conclusions: Overall, bedroom LAN exposure was associated with impaired glucose metabolism markers among young adults. Importantly, circadian-dependent meal timing may have potentially moderate effects on these associations. Keeping bedroom darkness at night and adhering to early eating pattern may be important public health strategies to reduce the risk of glucose metabolism disorders.

This scientometric review takes 351 documents from 1992-2021 as the research object based on the Web of Science database. With the help of CiteSpace, this study aims to construct visualization mapping knowledge domains, display the research status in shadow education more intuitively, contribute opportunities for further research, and provide a more visual basis for dialog among researchers, policymakers and interested actors in the field. This study, by building coauthor, coword, and cocitation knowledge visualization maps, demonstrates cooperation among authors, research hotspots and frontiers in the field. Our results show that shadow education has experienced a rapid expansion over the last decade but that the scope of the collaborative circle of academia needs to be further expanded. Furthermore, because of shadow education's variable forms, researchers need to pay extra attention to the scope of its definition. Parents are involved in too many of their children's educational choices; learning requires more self-drive and improved self-learning ability.

Abstract Magnons, bosonic quasiparticles carrying angular momentum, can flow through insulators for information transmission with minimal power dissipation. However, it remains challenging to develop a magnon-based logic due to the lack of efficient electrical manipulation of magnon transport. Here we show the electric excitation and control of multiferroic magnon modes in a spin-source/multiferroic/ferromagnet structure. We demonstrate that the ferroelectric polarization can electrically modulate the magnon-mediated spin-orbit torque by controlling the non-collinear antiferromagnetic structure in multiferroic bismuth ferrite thin films with coupled antiferromagnetic and ferroelectric orders. In this multiferroic magnon torque device, magnon information is encoded to ferromagnetic bits by the magnon-mediated spin torque. By manipulating the two coupled non-volatile state variables—ferroelectric polarization and magnetization—we further present reconfigurable logic operations in a single device. Our findings highlight the potential of multiferroics for controlling magnon information transport and offer a pathway towards room-temperature voltage-controlled, low-power, scalable magnonics for in-memory computing.

Abstract Realizing transformation from transparent insulating to transparent conducting, is a pursuing goal in designing and fabricating novel optoelectronic materials and devices. Here, a pronounced insulating to metal transition in anatase TiO2 thin films is achieved through ionic liquid gating, and interestingly the material maintains an invariable high optical transparency. It is revealed that the emergent metallic state can be attributed to the electron doping associated with the hydrogen ion intercalation. Importantly, the hydrogenation leads to the almost rigid shift of the Fermi energy and therefore maintains nicely the transparency at the visible light region. This result is in strong contrast with the case of oxygen vacancy doping, in which the optical bandgap is suppressed due to improved orbitals hybridization and intraband transition. Moreover, through synergistic ion‐electron doping, the selective control of the gating area and pattern is realized in the micrometer or even nanometer scale with extremely distinct physical properties, which can be employed to fabricate novel optical and electronic devices. The result greatly deepens the understanding of the underlying physics and formation mechanism of transparent conducting oxide (TCO) materials. It is envisioned that this work would provide a new pathway to design other potential optoelectronic materials with novel functionalities.

Abstract Twisted bilayer graphene (tBLG) provides a fascinating platform for engineering flat bands and inducing correlated phenomena. By designing the stacking architecture of graphene layers, twisted multilayer graphene can exhibit different symmetries with rich tunability. For example, in twisted monolayer-bilayer graphene (tMBG) which breaks the C 2z symmetry, transport measurements reveal an asymmetric phase diagram under an out-of-plane electric field, exhibiting correlated insulating state and ferromagnetic state respectively when reversing the field direction. Revealing how the electronic structure evolves with electric field is critical for providing a better understanding of such asymmetric field-tunable properties. Here we report the experimental observation of field-tunable dichotomic electronic structure of tMBG by nanospot angle-resolved photoemission spectroscopy (NanoARPES) with operando gating. Interestingly, selective enhancement of the relative spectral weight contributions from monolayer and bilayer graphene is observed when switching the polarity of the bias voltage. Combining experimental results with theoretical calculations, the origin of such field-tunable electronic structure, resembling either tBLG or twisted double-bilayer graphene (tDBG), is attributed to the selectively enhanced contribution from different stacking graphene layers with a strong electron-hole asymmetry. Our work provides electronic structure insights for understanding the rich field-tunable physics of tMBG.

Background: Exposure to light at night (LAN) has been associated with multiple adverse health outcomes. However, evidence is limited regarding the impacts of LAN exposure on human inflammation. Objectives: To examine the association between real-ambient bedroom LAN exposure with systemic inflammation and circadian rhythm of inflammatory markers. Methods: Using data from a prospective cohort study of Chinese young adults. At baseline, bedroom LAN exposure was measured with a portable illuminance meter; fasting blood sample for high-sensitivity C-reactive protein (hs-CRP) assay was collected. At 3-year follow-up, 20 healthy young adults (10 LANavg < 5 lx, 10 LANavg ≥ 5 lx) were recruited from the same cohort; time-series venous blood samples were sampled every 4 h over a 24 h-cycle for the detection of 8 inflammatory markers. Circadian rhythm of inflammatory markers was assessed using cosinor analysis. Results: At baseline, the average age of the 276 participants was 18.7 years, and 33.3 % were male. Higher levels of bedroom LAN exposure were significantly associated with increased hs-CRP levels. The association between bedroom LAN exposure and systemic inflammation was only significant in the inactive group (MVPA < 2 h/d) but not in the physically active group (MVPA ≥ 2 h/d). In addition, exposure to higher levels of nighttime light (LANavg ≥ 5 lx) disrupted circadian rhythms (including rhythmic expression, circadian amplitude and circadian phase) of some inflammatory cytokines and inflammatory balance indicators. Conclusion: Exposure to bedroom nighttime light increases systemic inflammation and disrupts circadian rhythm of inflammatory markers. Keep bedroom darkness at night may represent important strategies for the prevention of chronic inflammation. Additionally, for people living a community with higher nighttime light pollution, regular physical activity may be a viable option to counteract the negative impacts of LAN exposure on chronic inflammation.

Abstract Magnetic skyrmions have great potential for developing novel spintronic devices. The electrical manipulation of skyrmions has mainly relied on current-induced spin-orbit torques. Recently, it was suggested that the skyrmions could be more efficiently manipulated by surface acoustic waves (SAWs), an elastic wave that can couple with magnetic moment via the magnetoelastic effect. Here, by designing on-chip piezoelectric transducers that produce propagating SAW pulses, we experimentally demonstrate the directional motion of Néel-type skyrmions in Ta/CoFeB/MgO/Ta multilayers. We find that the shear horizontal wave effectively drives the motion of skyrmions, whereas the elastic wave with longitudinal and shear vertical displacements (Rayleigh wave) cannot produce the motion of skyrmions. A longitudinal motion along the SAW propagation direction and a transverse motion due to topological charge are simultaneously observed and further confirmed by our micromagnetic simulations. This work demonstrates that acoustic waves could be another promising approach for manipulating skyrmions, which could offer new opportunities for ultra-low power skyrmionics.

Abstract The anomalous Hall effect (AHE) that emerges in antiferromagnetic metals shows intriguing physics and offers numerous potential applications. Magnets with a rutile crystal structure have recently received attention as a possible platform for a collinear-antiferromagnetism-induced AHE. RuO2 is a prototypical candidate material, however the AHE is prohibited at zero field by symmetry because of the high-symmetry [001] direction of the Néel vector at the ground state. Here, we show AHE at zero field in Cr-doped rutile, Ru0.8Cr0.2O2. The magnetization, transport and density functional theory calculations indicate that appropriate doping of Cr at Ru sites reconstructs the collinear antiferromagnetism in RuO2, resulting in a rotation of the Néel vector from [001] to [110] while maintaining a collinear antiferromagnetic state. The AHE with vanishing net moment in the Ru0.8Cr0.2O2 exhibits an orientation dependence consistent with the [110]-oriented Hall vector. These results demonstrate that material engineering by doping is a useful approach to manipulate AHE in antiferromagnetic metals.

Abstract Engineering lattice defects have emerged as a promising approach to effectively modulate the functionality of devices. Particularly, antiphase boundaries (APBs) as planar defects have been considered major obstacles to optimizing the ionic conductivity of mixed ionic-electronic conductors (MIECs) in solid oxide fuel applications. Here our study identifies topotactically transformable APBs (tt-APBs) at the atomic level and demonstrates that they exhibit higher ionic conductivity at elevated temperatures as compared to perfect domains. In-situ observation at the atomic scale tracks dynamic oxygen migration across these tt-APBs, where the abundant interstitial sites between tetrahedrons facilitate the ionic migration. Furthermore, annealing in an oxidized atmosphere can lead to the formation of interstitial oxygen at these APBs. These pieces of evidence clearly clarify that the tt-APBs can contribute to oxygen conductivity as anion diffusion channels, while the topotactically non-transformable APBs cannot. The topotactic transformability opens the way of defect engineering strategies for improving ionic transportation in MIECs.

Abstract Exopolysaccharide (EPS) from Weissella cibaria has been devoted to the study of food industry. However, the anticancer activity of W. cibaria derived EPS has not yet been investigated. In this study, we obtained the EPS from W. cibaria D-2 isolated from the feces of healthy infants and found that D-2-EPS, a homopolysaccharide with porous web like structure, could effectively inhibit the proliferation, migration, invasion and induce cell cycle arrest in G0/G1 phase of colorectal cancer (CRC) cells. In HT-29 tumor xenografts, D-2-EPS significantly retarded tumor growth without obvious cytotoxicity to normal organs. Furthermore, we revealed that D-2-EPS promoted the apoptosis of CRC cells by increasing the levels of Fas, FasL and activating Caspase-8/Caspase-3, indicating that D-2-EPS might induce apoptosis through the extrinsic Fas/FasL pathway. Taken together, the D-2-EPS has the potential to be developed as a nutraceutical or drug to prevent and treat colorectal cancer.

Inflammatory bowel disease (IBD) is a group of chronic non-specific gastrointestinal inflammatory conditions, whose pathogenic factors and pathogenesis may be related to environmental factors, genetic susceptibility, gut microbiota and immune responses. Ferroptosis is a newly found cell death caused by the accumulation of iron-dependent lipid hydroperoxides, which is tightly regulated by a lipid repair system including glutathione (GSH) and glutathione peroxidase 4 (GPx4). Increasing studies have reported the fundamental features of ferroptosis in the injured gastrointestinal tract in IBD patients, including iron deposition, GSH exhaustion, GPx4 inactivation, and lipid peroxidation. Furthermore, regulating the key ferroptosis-related genes may alter the progression, severity, or even morbidity of IBD. We reviewed the basic mechanism of ferroptosis, and the prospect of ferroptosis pathways as therapeutic targets in IBD. In addition, the initiation of ferroptosis for improving IBD by extrinsic (transporter-dependent) or intrinsic (enzyme-regulated) pathway, may be a new direction for clinical treatment of IBD.

Abstract Interconversion of spin and charge current provides a key route for low‐power spin memory and logic devices. Recent advances have revealed efficient spin‐charge interconversion in 4d and 5d transition metal oxides. However, the strategies to tune the conversion efficiency, essential for the generation and detection of spin‐current, are limited to engineering the crystalline structure of oxides. Here, a simple and broadly applicable approach by tuning the cation stoichiometry is reported. In the model system of 5d perovskite SrIrO3, it is shown that a significant Ir cation deficiency is induced by controlling the oxygen partial pressure during deposition. This off‐stoichiometry leads to an enhancement of the spin‐to‐charge conversion efficiency by around three times, accompanied by an increase of electrical resistivity at room temperature. Furthermore, a significant increase of inverse spin Hall voltage is observed by implementing the Ir‐deficient SrIr1‐xO3, highlighting the promising role of atomic defects in developing oxides for sensitive spin‐current detection. This work opens a new pathway to engineer the spin‐charge interconversion efficiency in oxides and offers new opportunities to integrate complex oxides in energy‐efficient spintronic devices.

Abstract Ionic liquids provide versatile pathways for controlling the structures and properties of quantum materials. Previous studies have reported electrostatic gating of nanometer-thick flakes leading to emergent superconductivity, insertion or extraction of protons and oxygen ions in perovskite oxide films enabling the control of different phases and material properties, and intercalation of large-sized organic cations into layered crystals giving access to tailored superconductivity. Here, we report an ionic-liquid gating method to form three-dimensional transition metal monochalcogenides (TMMCs) by driving the metals dissolved from layered transition metal dichalcogenides (TMDCs) into the van der Waals gap. We demonstrate the successful self-intercalation of PdTe2 and NiTe2, turning them into high-quality PdTe and NiTe single crystals, respectively. Moreover, the monochalcogenides exhibit distinctive properties from dichalcogenides. For instance, the self-intercalation of PdTe2 leads to the emergence of superconductivity in PdTe. Our work provides a synthesis pathway for TMMCs by means of ionic liquid gating driven self-intercalation.

Abstract Multistate resistive switching device emerges as a promising electronic unit for energy-efficient neuromorphic computing. Electric-field induced topotactic phase transition with ionic evolution represents an important pathway for this purpose, which, however, faces significant challenges in device scaling. This work demonstrates a convenient scanning-probe-induced proton evolution within WO3, driving a reversible insulator-to-metal transition (IMT) at nanoscale. Specifically, the Pt-coated scanning probe serves as an efficient hydrogen catalysis probe, leading to a hydrogen spillover across the nano junction between the probe and sample surface. A positively biased voltage drives protons into the sample, while a negative voltage extracts protons out, giving rise to a reversible manipulation on hydrogenation-induced electron doping, accompanied by a dramatic resistive switching. The precise control of the scanning probe offers the opportunity to manipulate the local conductivity at nanoscale, which is further visualized through a printed portrait encoded by local conductivity. Notably, multistate resistive switching is successfully demonstrated via successive set and reset processes. Our work highlights the probe-induced hydrogen evolution as a new direction to engineer memristor at nanoscale.