Browse Articles

Green-synthesized silver nanoparticle-enhanced nanofiltration mixed matrix membranes for high-performance water purification

Field-free spin–orbit switching of canted magnetization in Pt/Co/Ru/RuO2(101) multilayers

Achieving field-free current-induced switching of perpendicular magnetization is crucial for the advancement of spin–orbit torque magnetic random access memory technology. In our study on the Pt/Co/Ru/RuO2(101) system, we have demonstrated field-free switching via current injection along the RuO2[010] axis. We found that the system features a tilted easy axis, deviating from the out-of-plane orientation toward the RuO2[1¯01] direction. The application of current perpendicular to this tilted axis generates a significant out-of-plane effective field, enabling field-free magnetization switching. Our findings also suggest that fine-tuning the thickness of the Ru layer to change the tilt angle can substantially reduce the critical switching current density. This work offers a promising approach for controlling the tilting magnetization, which is vital for the development of RuO2-based magnetic devices.

A hybrid attention multi-scale fusion network for real-time semantic segmentation

AbstractIn semantic segmentation research, spatial information and receptive fields are essential. However, currently, most algorithms focus on acquiring semantic information and lose a significant amount of spatial information, leading to a significant decrease in accuracy despite improving real-time inference speed. This paper proposes a new method to address this issue. Specifically, we have designed a new module (HFRM) that combines channel attention and spatial attention to retrieve the spatial information lost during downsampling and enhance object classification accuracy. Regarding fusing spatial and semantic information, we have designed a new module (HFFM) to merge features of two different levels more effectively and capture a larger receptive field through an attention mechanism. Additionally, edge detection methods have been incorporated to enhance the extraction of boundary information. Experimental results demonstrate that for an input size of 512 × 1024, our proposed method achieves 73.6% mIoU at 176 frames per second (FPS) on the Cityscapes dataset and 70.0% mIoU at 146 FPS on Camvid. Compared to existing networks, our Model achieves faster inference speed while maintaining accuracy, enhancing its practicality.

Reduced sound velocity in PbZrO3 thin film during antiferroelectric to ferroelectric transition revealed by picosecond acoustics

The antiferroelectric-to-ferroelectric (AFE-FE) phase transition has attracted considerable attention due to its potential applications in high-strain transducers, thermal switching, and pulsed-power devices. To deepen our understanding of this transition and enable its functionalities, ultrafast dynamics, especially lattice dynamics of antiferroelectricity, are essential to be demonstrated. In this work, the picosecond acoustics technique is applied to measure the sound velocity of a high-quality PbZrO3 epitaxial thin film with a thickness of ∼110 nm, determining it to be 5879 ± 11 m/s. More importantly, our in situ measurements reveal a reduction in sound velocity of approximately 6% during the AFE-FE phase transition under an external electric field of ∼364 kV/cm at ambient conditions. This reduction can increase to about 12% with an elevated electric field of approximately 545 kV/cm. Additionally, we found that this field-induced ferroelectric phase is metastable and the recovery takes up to tens of hours at ambient conditions, indicating a memory effect of the field-induced state. These findings suggest that the AFE-FE phase transition in PbZrO3 thin films holds promise for applications in acoustic wave manipulation.

Control of flow deflection angle around the corner using microjet array

Imprinting of stochastic magnetic domain configurations by fluctuating interlayer coupling

Competing interaction within magnetic materials leads to the formation of complex magnetic domain configurations such as stripe domains, labyrinthine domains, magnetic bubbles, and skyrmions, which are fingerprints of different magnetic materials. An effective tailoring of these competing interactions and the resultant magnetic domain configurations by extrinsically means is of current interest. Through depositing an interfacially asymmetric Ta/CoFeB/MgO/Ta multilayer on a rare-earth-doped yttrium iron garnet of composition SmLu: YIG film, we show that the magnetic domain configurations from the bottom SmLu: YIG film can be partly imprinted onto the top Ta/CoFeB/MgO/Ta multilayer. The formation of stochastic domain configurations, such as labyrinthine domains, parallel stripe domains, and magnetic bubbles in the Ta/CoFeB/MgO/Ta multilayer, is jointly studied by using polar magneto-optical Kerr effect microscope and anomalous Hall effect measurements. The underlying physics is attributed to the fluctuating interlayer dipole–dipole interaction that results in the partial imprinting, which could substantially modify the intrinsic magnetism of the top Ta/CoFeB/MgO/Ta multilayer and leading to the formation of stochastic domain configurations. Our results provide an effective approach for tailoring the competing interaction in magnetic materials and for application scenarios in which the formation of stochastic domain configurations is required.

Follow-up care needs and motivational factors for childhood cancer survivors and their parents in Germany

AbstractThis study aims to explore the long-term follow-up needs and motivations of childhood and adolescent cancer survivors and their parents to attend follow-up care in Germany, given the inconsistent adherence to national follow-up guidelines. We developed interview guidelines based on the Theory of Planned Behavior and the stereotype priming model to explore motivations and barriers related to follow-up care. We conducted a total of 36 episodic narrative interviews with adolescent (ages 13–17) and adult (ages 18–45) survivors of pediatric cancer, as well as their parents. We analyzed the transcripts qualitatively using thematic content analysis, while quantitative analysis through multiple regression models was used to support the qualitative findings and identify predictors of follow-up care attendance. We identified key themes across age groups, including a strong need to “return to normal life” and a desire for ongoing organizational and social support. Both survivors and parents highlighted specific needs, including timely, personalized health information and practical help with healthcare logistics. Adolescents particularly valued emotional support from their social circles, whereas adult survivors and parents expressed a need for more structured psychosocial and logistical assistance. The findings suggest that both age and the time elapsed since diagnosis play a role in affecting survivors’ perceived control to attend guideline-based follow-up care. Our findings suggest that a differentiated approach to follow-up care, with age-appropriate support structures, and tailored guidelines, may improve adherence among survivors and their parents. To enhance follow-up care adherence among cancer survivors, healthcare providers could offer tailored, age-specific information and practical assistance with healthcare logistics. Additionally, providing emotional and psychosocial support resources for both survivors and their parents can help address their unique needs at different stages of recovery.Trial registration: Registered at German Clinical Trial Register (ID DRKS00025960 and DRKS00026092).

Erratum: “MOCVD growth of β-Ga2O3 with fast growth rates (&amp;gt;4.3 <i>μ</i> m/h), low controllable doping, and superior transport properties” [Appl. Phys. Lett. <b>125</b> , 242106 (2024)]

Comprehensive bioinformatics analysis reveals novel potential biomarkers associated with aging and mitochondria in osteoporosis

Visualization of the phonon evolution behavior in NaNbO3 single crystal during field-induced phase transition by <i>in situ</i> Raman spectroscopy

NaNbO3 (NN) is a significant lead-free alternative for pulse power systems or nonvolatile memories due to its antiferroelectric P phase at room temperature. However, a comparable free energy between P phase and another ferroelectric Q phase leads to an irreversible transition from P to Q phase just under a weak electric field, which results in the unobservable double hysteresis loops. In addition, recent studies reveal that the critical field needed during the transition process is inconsistent between in situ microstructure characterization and macroscopic polarization measurement. Consequently, the intricate field-induced phase transition in NN is perplexing. Based on high sensitivity of Raman spectroscopy to symmetry breaking in lattices, this work systematically investigates the in situ Raman spectra of NN single crystals, analyzing the evolution and depolarization behavior of various phonons under an electric field. Correspondingly, the transition from P to Q phase is determinately identified, accompanied by in-depth understanding of the phonon dynamics of field-induced phase transition. This present work provides a reliable experimental foundation for further probing on the transition mechanism of ferroelectric/antiferroelectric order in dielectrics, as well as facilitating the performance control and application development of NN-based devices.

6-hydroxygenistein attenuates hypoxia-induced injury via activating Nrf2/HO-1 signaling pathway in PC12 cells

Phase stability and transition behaviors of (Bi<i>x</i>In1−<i>x</i>)2Se3 alloy

The Bi2Se3–In2Se3 layered system has garnered significant attention and extensive research due to its versatile properties, yet its structural properties and phase stability remain elusive. Here, using first-principles calculations with van der Waals interactions, we systematically study the phase stability and transition behavior of (BixIn1−x)2Se3 alloys. Our results reveal a contrasting stability profile between Bi2Se3 and In2Se3, with the former exhibiting a distinct preference for the β phase over the α phase, while the latter shows similar stabilities in both phases, thus partially addressing previously reported ground-state inconsistencies. Exploring composition–structure relationships, we demonstrate that Bi incorporation in low concentrations stabilizes the β phase, consistent with early experimental observations. Further analysis based on the cation orbital properties indicates that the preference of Bi for octahedral sites over tetrahedral ones drives the small critical composition for the α→β phase transition. This work enhances our understanding of phase stability in (BixIn1−x)2Se3 alloys, providing insights for future design of monophasic materials and advanced applications.

Early detection of autism spectrum disorder: gait deviations and machine learning

Control of structural phase transition and energy storage behavior through cooling rate in (Bi0.5Na0.5)TiO3–BaTiO3 ceramics

In lead-free (Bi0.5Na0.5)TiO3–BaTiO3 (BNT–BT) ceramics, the BNT-rich side has R3c ferroelectric domains at room temperature, and modulated P4bm tetragonal nanodomains develop within the R3c rhombohedral phase at approximately the depolarization temperature Td. Such structural phase transitions have conventionally been modulated by doping with additives or by controlling the composition. However, it is considered that the coexistence region between the R3c and P4bm phases is important for enhancing the energy storage behavior because the phase reversal between them, caused by the electric field, can cause the BNT-based ceramics to exhibit an antiferroelectric-like pinched hysteresis loop. In this study, the structural phase transition of BNT–BT ceramics is promoted through process control, that is, by adjusting the cooling rate, and then the stabilization of the P4bm phase and the expansion of the coexistence region of the R3c and P4bm phases were examined, which results in enhanced energy storage behavior. Consequently, BNT–BT ceramics prepared at a slower cooling rate (0.01 °C s−1) than that of normal firing (0.05 °C s−1) demonstrate the stabilization of the P4bm phase and expansion of the coexistence region of the R3c and P4bm phases. Therefore, process control modulates the structural phase transition, which can cause enhanced energy storage behavior.

Explainable attention based breast tumor segmentation using a combination of UNet, ResNet, DenseNet, and EfficientNet models

Printing quantum dot color conversion layer in etch pits using EHD technology based on mini-LED

The rapid development of display technologies has boosted the demand for efficient and high-resolution color conversion techniques. However, conventional approaches such as photolithography and inkjet printing are constrained by limitations in pixel size and material compatibility, making it difficult to meet the demands of industrialization. Due to the low luminescence efficiency of the red quantum dot (QD) material, an innovative quantum dot color conversion (QDCC) layer structure was proposed in this study. The red QD film was prepared in pixel pits below the glass surface using electrohydrodynamic inkjet printing, thus integrating the QD film into the glass substrate. This results in a more vivid and accurate full-color display. The results indicate that the fabricated QDCC layer achieves a pixel size of 216 × 116 μm2, with a maximum external quantum efficiency (EQE) of 5.81% and a luminance of 1 315 205 cd/m2. To improve the performance of the device, the transparent photoresist used for leveling between the LEDs was substituted with a black photoresist. Although the EQE changes to 3.93% and the luminance changes to 1 206 038 cd/m2, the color coordinates move closer to the red region, changing from (0.4396, 0.2089) to (0.4786, 0.2258). This innovative method significantly not only reduces the thickness and weight of the display but also improves its color performance. This research lays the foundation for high-performance displays, paving the way for ultra-thin and energy-efficient display technologies.

Ensemble genetic and CNN model-based image classification by enhancing hyperparameter tuning

Millikelvin Nb nanoSQUID-embedded tunable resonator fabricated with a neon focused-ion-beam

SQUID-embedded superconducting resonators are of great interest due to their potential for coupling highly scalable superconducting circuits with quantum memories based on solid-state spin ensembles. Such an application requires a high-Q, frequency-tunable resonator that is both resilient to magnetic field and able to operate at millikelvin temperatures. These requirements motivate the use of a higher Hc metal such as niobium; however, the challenge then becomes to sufficiently reduce the operating temperature. We address this by presenting a monolithic Nb nanoSQUID-embedded resonator, where neon focused-ion-beam fabrication of the nanoSQUID results in a device displaying frequency tunability at T=16 mK. In order to assess the applicability of the device for coupling to small spin clusters, we characterize the flux sensitivity as a function of microwave drive power and externally applied magnetic field and find that the noise is dominated by dielectric noise in the resonator. Finally, we discuss improvements to the device design that can dramatically improve the flux sensitivity, which highlights the promise of Nb SQUID-embedded resonators for hybrid superconductor-spin applications.

Magnetic properties of different phases iron oxide nanoparticles prepared by micro emulsion-hydrothermal method

Photon number-resolving aluminum kinetic inductance detectors

We study the multi-photon energy resolution and demonstrate photon counting up to about 30 photons at near-infrared wavelengths in a kinetic inductance detector made from aluminum (Al) film. The detector has a lumped-element design comprising a large interdigitated capacitor in parallel with a narrow inductive strip. A fiber-coupled lens is used to focus the light onto the inductive absorber to minimize photon scattering. Detectors with different designs and film thicknesses are studied. From the histogram of the optimally filtered multi-photon response pulse height, we find that the square of the energy resolution of the n-photon peak ΔEn2 increases linearly with the absorbed photon energy nhν. The detector made from a thicker Al film has a smaller slope of ΔEn2 with nhν, suggesting lower phonon loss in a thicker absorber. We also discuss other factors that limit the energy resolution and maximum resolvable photon number, including the dark noise and position-dependent response.