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Piezoelectric activation of dual lattice-oxygen mechanism through OH− Grotthuss transport in water electrolysis
Retraction: Utilization of solid mine waste in the building materials for 3D printing
All-electrical switching of spin texture in a strain-tunable 2D Janus ferroelectric altermagnet
Altermagnetism (AM), a collinear magnetic phase with momentum-dependent spin splitting, is a promising candidate for strong magnetoelectric coupling. However, realizing direct and tunable coupling between ferroelectricity (FE) and AM within a single two-dimensional (2D) material remains an outstanding challenge. Here, based on first-principles calculations, we identify a distorted phase of monolayer Janus VOClBr as an intrinsic 2D FE-AM. This phase demonstrates robust magnetoelectric coupling, as evidenced by a complete reversal of momentum-space spin polarization upon FE switching and further supported by spin texture analysis and the magneto-optical Kerr effect. Notably, the FE properties are highly strain-tunable: a biaxial compression strain of −4% reduces the FE polarization switching barrier by approximately 87%, whereas a tensile strain of +3% induces a phase transition to an antiferromagnet. Leveraging the lock-in between the electrically controlled spin texture and the magneto-optical Kerr effect signal, we propose a non-volatile, polymorphic spintronic memory device featuring all-electrical writing and optical readout. This work establishes 2D FE-AMs as a versatile platform for coupled ferroic orders and paves the way for voltage-controlled, multifunctional spin-logic devices.
Retraction Note: Deficiency of endothelial sirtuin1 in mice stimulates skeletal muscle insulin sensitivity by modifying the secretome
Retraction: Green fabricated zinc oxide nanoformulated media enhanced callus induction and regeneration dynamics of Panicum virgatum L.
Stress-modulated ferroelectricity and dielectric response in HfO2
HfO 2 -based ferroelectrics offer exceptional silicon compatibility and scalability for next-generation nonvolatile memory, yet the fundamental role of mechanical stress in their functional properties remains unresolved. This study provides direct experimental and theoretical evidence that tensile stress intrinsically governs the ferroelectric and dielectric response of Hf0.5Zr0.5O2. Using a uniquely designed stretchable ferroelectric capacitor (W/Hf0.5Zr0.5O2/TiN) on a polyimide substrate, we perform in situ measurements under controlled uniaxial tensile strain. Concurrent first-principles calculations simulate strain in the polar orthorhombic Pca21HfO2 phase. Both approaches conclusively demonstrate that switchable polarization monotonically decreases with strain, dielectric permittivity increases, leakage current reduces. These reversible trends are attributed to strain-induced rearrangement of the crystal structure (not electronic effects). In turn, domain reorientation and phase exchange are ruled out as the primary mechanism. Discrepancies in the absolute values between the experiment and the theory arise from polycrystallinity, interfacial tetragonal layers, and grain boundaries. Our findings resolve long-standing debates on stress-mediated ferroelectricity in HfO2, establishing that intrinsic lattice deformation—not extrinsic factors—primarily dictates property changes. This work enables precise stress engineering for HfO2-based electronic devices.
Dynamic ligand-vacancy engineering drives metal dimerization for efficient urea electrooxidation
Investigating the effects of continuous theta-burst stimulation over the posterior parietal cortex on holistic processing of composite faces: evidence from cognitive modeling
Efficient interaction with complex visual environments depends on the balance between global and local processing, with a natural tendency to prioritize global information—a phenomenon known as the global advantage. This study investigates how non-invasive brain stimulation using continuous theta-burst stimulation (cTBS) over the posterior parietal cortex (PPC) affects this balance, with a focus on holistic face processing. We conducted a within-subject, crossover, sham-controlled experiment involving 36 participants who completed Navon and composite face tasks before and after cTBS stimulation over the left and right PPC. Cognitive modeling using the Diffusion Model of Conflict (DMC) was employed to examine the cognitive mechanisms involved and compare global and local processing in experimental versus sham conditions. The results confirmed the expected global precedence effect and holistic processing in both tasks but revealed no significant impact of cTBS over the right PPC on task performance in terms of accuracy or response time. However, under incongruent conditions, cTBS over the left PPC led to slower responses to local targets, particularly when compared with the sham condition. Despite these localized effects, no significant changes were observed in composite face task performance following either left or right PPC stimulation. Overall, our findings highlight the complexity of the neural mechanisms governing global-local processing and the limited impact of single-session cTBS over the PPC in altering the cognitive mechanisms underlying these processes. Further research is needed to better understand the role of the PPC in holistic and hierarchical visual processing.
Gate voltage-controlled magnetic anisotropy at the Pt-porphyrin functionalized graphene/NiFe interface
We report a novel approach for engineering large voltage-controlled magnetic anisotropy (VCMA) and enhanced spin–orbit coupling (SOC) at the interface between single-layer graphene (SLG) and NiFe through non-covalent functionalization with platinum (II) 5,10,15,20-tetraphenyl porphyrin (Pt-porphyrin). Using chemical vapor grown SLG, we demonstrate that Pt-porphyrin functionalization significantly increases the SOC, and strong interfacial charge redistribution and orbital hybridization between functionalized graphene and ferromagnet enable robust voltage modulation of interfacial magnetic anisotropy, as confirmed by spin-torque ferromagnetic resonance measurements. A substantial VCMA coefficient of (ξ) 375.6 fJ V−1 m−1 is achieved, accompanied by an order-of-magnitude enhancement in spin-torque efficiency (θeff−sh) compared to pristine SLG. The resonance field exhibits a clear, reversible shift under applied gate voltage, confirming robust electric-field modulation of interfacial magnetic anisotropy. Raman and x-ray photoelectron spectroscopy confirm the structural integrity and effective charge transfer at the functionalized interface. Electrical characterization of back-gated graphene field-effect transistors further reveals tunable electronic properties upon functionalization. The functionalized interface remains chemically stable under ambient conditions and throughout device fabrication processes. Our results demonstrate that non-covalent functionalization of graphene with Pt-porphyrin induces a gate-tunable interfacial electronic reconstruction, which simultaneously enhances spin–orbit-mediated charge–spin conversion and VCMA in an adjacent ferromagnet. We believe this will provide a promising platform for scalable and energy-efficient memory and logic technologies.
Zinc isotope evidence for extensive carbonate recycling in the Arctic asthenosphere
The anti-infective potential of human milk oligosaccharides in carbohydrate powder in implant-associated infection with Staphylococcus aureus
Introduction Periprosthetic joint and implant-associated infections remain serious complications despite highly standardized diagnostic and therapeutic protocols. Repeated revision procedures substantially increase morbidity and the risk of therapeutically uncontrollable infection scenarios. This pilot study, we evaluated the effect of HMO (human milk oligosaccharides)-containing carbohydrates on S. aureus biofilm formation using crystal violet assays and implant models. Methods S. aureus EDCC 5055 biofilm formation was quantified in the presence of HMO-containing carbohydrates (HMO-C) at concentrations of 5%, 7%, 9%, and 11% and lactose-alone in 96-well plates. After processing, the plate contents were read out using a 595nm Phomo plate reader (Anthos Mikrosystems, Krefeld, Germany). Biofilm activity was further evaluated on titanium disks pre-incubated with HMO-C solutions. Bacterial growth kinetics were also analyzed in TSB with the 5% to 11% HMO-C solutions. Results The results demonstrated a significant reduction in S. aureus biofilm formation with the addition of HMO-C (HMO-C-5%: mean value ( x¯ )=0.271nm; p = 0.021; HMO-C groups 7%−11%: x¯ = 0.211nm, 0.179nm, 0.147nm; All p = 0.001) against the positive control EDCC 5055 (PC) ( x¯ = 0.335nm). Lactose (L) alone did not significantly affect biofilm formation (L5%−11%: p = 1.0). No significant biofilm reduction was observed for titanium implants, though medium changes indicated bacterial inhibition at higher HMO-C solutions (9%−11%: x¯ = 0.844nm, 0.940nm; Both p = 0.001). Conclusion Media supplemented with HMOS-C significantly reduced S. aureus ED CC 5055 biofilm formation in vitro in the crystal violet microtiter plate assay. Bacterial invasion on titanium could not be demonstrably changed, but S. aureus growth curve was significantly reduced. Further studies with optimized implant models and standardized HMO formulations are warranted to clarify the translational potential of HMO-C for the prevention of implant-associated infections.
Improved Ec control in Hf1−xZrxO2 FeNAND applications using SiO2 nanolaminate structure
The coercive field (Ec) is a key parameter governing the switching behavior of ferroelectric devices, yet its effective modulation remains challenging due to intrinsic material constraints. In this study, we demonstrate a domain-wall-engineering approach to control Ec in Hf1−xZrxO2 (HZO) thin films by inserting 0.5 nm-thick interlayers without altering the overall film thickness. Incorporation of ZrO2 interlayers reduced Ec by 34.7%, enabling low-voltage and energy-efficient operation for ferroelectric random-access memory. Conversely, integrating SiO2 interlayers increased Ec by 62.8%, which is particularly advantageous for ferroelectric NAND (FeNAND) applications requiring a wide memory window. The effectiveness of this strategy was validated using InGaZnO-based ferroelectric field-effect transistors, where the HZO/SiO2 stack achieved enhanced multi-level cell functionality, a substantial threshold-voltage shift, and a gradual switching slope. These results highlight a scalable and CMOS-compatible method to overcome the conventional tradeoffs between operating voltage and memory density, offering a promising route toward high-performance FeNAND and future three-dimensional nonvolatile memory architectures.
Retraction Note: Re-engineered BCG overexpressing cyclic di-AMP augments trained immunity and exhibits improved efficacy against bladder cancer
Reliability of durometry to assess firmness of calcinosis lesions in Juvenile and adult dermatomyositis
Background/Objective Dermatomyositis (DM) and juvenile dermatomyositis (JDM) are inflammatory myopathies affecting multiple organs, including muscle and skin. Calcinosis is a complication of DM/JDM that causes significant morbidity; however, few tools exist to assess calcinosis in DM/JDM patients This study aimed to evaluate the reliability of durometry measurements to assess the firmness of calcinosis lesions in DM and JDM patients. Methods Calcinosis firmness was measured using a handheld digital durometer. Six investigators across 3 institutions examined DM/JDM calcinosis lesions by durometry, as well as control readings in healthy unaffected skin/subcutaneous tissue in similar anatomic areas, recording three readings per site. Intra-rater and inter-rater intraclass correlations were evaluated. Results We enrolled 57 patients and gathered 709 measurements (443 calcinosis lesions; 266 control lesions) over eleven anatomic regions. Intra-rater reliability was high across sites, while inter-rater reliability varied, being moderate to good in most areas, but poor in the thigh and anterior calf. Durometry readings were higher in calcinosis lesions than control sites overall. Measurements moderately correlated with qualitative physician assessments. Due to our study’s cross-sectional nature, we could not assess calcinosis over time. Conclusion Durometry is a novel, reliable, quantitative measure in assessing and characterizing targeted calcinosis lesions of DM/JDM patients.
Stress and doping analysis of low n-doped GaN layers on various substrates by micro-Raman mapping
In this work, using micro-Raman spectroscopy mapping, we propose a methodology to separate the stress effect from the n-doping effect on A1LO and E2H GaN phonon modes frequency for low n-doped (<1017 cm−3) GaN layers grown on various substrates (GaN, sapphire, and silicon). This methodology shows a linear relation between the two phonon modes, in which the slope corresponds to GaN biaxial stress coefficients ratio KA1LOB/KE2HB and is 0.76 ± 0.01. Our value may act as a useful guideline for selecting or refining KE2HB and KA1LOB values. Samples that are mainly biaxially stressed show good agreement with the linear relation independently of the substrate. As for GaN/GaN samples, the change of slope indicates that layers are predominantly under dislocation-induced stress. However, independently of the substrate, the y-intercept increases with the n-carrier concentration, which provides a qualitive estimation of the net doping.
Self-reorganization and information transfer in large-scale models of fish schools
Identifying clinico-radiological determinants of post-stroke fatigue 3 months post-stroke in a French hospital-based cohort of non-severe stroke patients without psychiatric comorbidities
Post-stroke fatigue (PSF) is an overlooked and debilitating condition. As a multidimensional construct, fatigue encompasses physical, cognitive, and emotional components, complicating efforts to understand PSF pathophysiological mechanisms and identify key predictors. We aimed to investigate the impact of lesion characteristics on different facets of subacute PSF while accounting for socio-demographic, psychological, and neurological factors. We assessed 231 patients with first-ever mild ischemic stroke without recent anxiety or depressive disorders using the Multidimensional Fatigue Inventory (MFI) at 3 months and the Hospital Anxiety and Depression Scale (HAD), alongside routine clinical evaluations. Lesion analysis was performed using two approaches: a voxel-based method using support vector regression-based multivariate lesion-symptom mapping (SVR-LSM), and a network-based method using principal component analysis (PCA) of lesioned gray and white matter regions. PSF had an overall prevalence of 20.8%, was more frequent in women and younger patients, and was associated with HAD scores. SVR-LSM identified associations between lesions in the right corona radiata and external capsule with total MFI scores, but not with HAD scores. After adjusting for relevant confounders, the network-based approach revealed associations between mental fatigue and reduced activity subdimensions and brain components involving cerebro-cerebellar tracts. Our findings indicate that, in a relatively homogeneous population, PSF arises from an interplay of socio-demographic, emotional, and cerebral risk factors. The involvement of motor pathways raises the possibility that neuronal overactivity, compensating for disrupted networks, may contribute to long-term fatigue. Further studies in more diverse populations along with whole-brain analyses would validate the generalizability of our results.
Study of leakage current in GaN junction field-effect transistor under heavy ion radiation
GaN junction field-effect transistors (JFETs) were fabricated and subjected to 333.7 MeV gold (Au) ion irradiation to investigate the effects of swift heavy ions on device performance. Electrical characterization following irradiation revealed a significant and permanent increase in off-state leakage current. The leakage was attributed to a vertical conduction mechanism, likely to originate from latent ion tracks formed within the device during SHI exposure. The results indicate a latent track-induced vertical leakage path in GaN JFETs under SHI irradiation. Temperature-dependent current–voltage measurements indicated a voltage-dependent activation energy, suggesting a field-assisted transport process. Device simulations reproduced the experimental leakage behavior and identified the critical leakage path at the p+-GaN/p-GaN region, where the local electric field is most intense. The conduction mechanism was found to be consistent with the Poole–Frenkel emission model, from which a barrier height of approximately 0.38 eV was extracted. These findings offer insights into SHI-induced degradation in GaN devices and provide guidance for designing radiation-hardened GaN electronics for space applications.