Browse Articles

Enhanced visible-light manipulation of the ferromagnetism in 3D cobalt nanosphere by sphere size engineering

Rapid and energy-efficient magnetization control is essential for advancing next-generation magnetic sensors and memory technologies. Photovoltaic gating of magnetism via light irradiation leverages advances in solar-cell engineering and electric-field-controlled magnetism, offering enhanced tunability at reduced power consumption. In this study, we report the fabrication of a cobalt nanosphere-photovoltaic material thin-film device. By systematically tuning the nanosphere diameter, concentration, and film thickness, we achieved an 11.5% reduction in magnetization under visible-light illumination (200 mW/cm2, 6.93 × 1017 photons cm−2 s−1). Notably, the relative magnetization reduction scales linearly with 1/r2, where r is the effective nanosphere radius. This behavior is attributed to a surface-electrical potential conservation mechanism, suggesting that increasing the surface-area-to-volume ratio enhances magneto-optical tunability. These insights provide a rational design strategy for light-modulated magnetic nanodevices with potential applications in reconfigurable sensors and memory elements.

Molecular weight fractionated extracellular polymeric substances (EPS) impart different aggregation characteristics on polystyrene nanoplastics

Triple point-type morphotropic phase boundary in ferromagnetic (1 − <i>x</i> )TbFe2– <i>x</i> NdFe2 system and corresponding magnetoelastic response

The morphotropic phase boundary (MPB) phenomenon plays a pivotal role in ferromagnetic systems for achieving field-induced enhancement of magnetoelastic responses. However, conventionally titled MPBs often show inferior temperature stability, resulting in significant degradation of magnetoelastic performance over broad temperature ranges. In this work, we designed a vertical phase boundary between the tetragonal and rhombohedral phases in the ferromagnetic (1 − x)TbFe2–xNdFe2 system, originating from a structural triple point (xTP). At the MPB composition (xMPB), large low-field magnetostriction, narrow magnetic hysteresis, and minimal magnetocrystalline anisotropy were simultaneously achieved at room temperature. In situ high-resolution transmission electron microscopy (HRTEM) revealed the coexistence of nanoscale rhombohedral and tetragonal magnetic domains (&amp;lt;10 nm) that persist over a wide temperature range. The formation of such nanodomains is attributed to reduced domain wall energy resulting from near-vanishing magnetocrystalline anisotropy between the two phases. Based on high-resolution synchrotron x-ray diffraction, in situ HRTEM, and magnetometry results, a comprehensive composition–temperature phase diagram was established for this system. The Landau free-energy analysis further demonstrates that the proximity of xMPB to xTP leads to an isotropic free-energy landscape, facilitating easy magnetization rotation under external fields and leading to enhanced magnetoelastic response with low hysteresis. This study demonstrates that engineering vertical MPBs provides an effective strategy for designing high-performance, temperature-stable functional magnetic materials.

Defect mediated pulse terahertz emission from thiocyanate-treated hybrid perovskite nanoparticles: role of the orientation of built-in surface electric field

Probing hysteresis and bifurcation dynamics in reactive radio frequency plasmas

Hysteresis between capacitive (E) mode and inductive (H) modes is a fundamental characteristic of radio frequency (RF) plasmas that are driven by a saddle-node bifurcation. While considerable research has focused on the static characteristics of this bistability in noble gases, the temporal dynamics underlying these transitions, especially in reactive electronegative plasmas, remain largely unexplored. This limits the ability to predict how fast and under what conditions nonlinear transitions occur in RF systems. This study introduces a framework that couples predictive modeling with ultrafast experimental diagnostics to reveal how electronegative chemistry governs bifurcation dynamics and bistability. A global power balance model is developed that links shifts in the electron energy distribution with state-dependent electron losses to determine the location and shape of the hysteresis loop. The model predicts that dissociative attachment in O2 provides negative feedback opposing stepwise ionization, narrowing the hysteresis window and increasing the power threshold for mode transitions compared to pure argon. These predictions are validated using single-shot terahertz time-domain spectroscopy to measure plasma refractive index changes during mode switching and through the bistable region in RF plasmas, complemented by broadband high-speed imaging. The combined results confirm model predictions and reveal an asymmetry in transition timescales: while O2 addition slows the forward E→H transition, it accelerates the reverse H→E collapse by roughly 66%. This work quantifies how electron loss processes, particularly attachment and transport, play an active, state-dependent role in shaping hysteresis and mode dynamics in reactive RF plasmas.

CSWin-MDKDNet: cross-shaped window network with multi-dimensional fusion and knowledge distillation for medical image segmentation

Lattice geometry-dependent magnon modes and harmonic generation in Permalloy antidot waveguides

Custom-engineered nanomagnonic waveguides with enhanced nonlinear properties are pivotal for advancing next-generation wave-based spintronic technologies. In this work, we systematically explore how lattice geometry influences the linear and nonlinear dynamics of Permalloy antidot waveguides. Three lattice configurations—square, rhomboid, and honeycomb—are examined. Our results reveal that introducing antidots generates localized magnon modes alongside propagating spin waves, with geometry strongly dictating localization behavior. Spin waves exhibit selective channel propagation, and in the nonlinear regime, we observe the presence of both integer and fractional harmonics. The 1.5fexc mode displays behavior similar to that of the fundamental modes, propagating through the channels, while the second harmonic reveals antisymmetric characteristics with multiple nodes across the channels. Notably, harmonic-generation efficiency in honeycomb lattices is nearly four times higher than in reference waveguides without antidots, and the second harmonic's performance depends on lattice positioning. Direct spin-wave imaging via Brillouin light microscopy confirms these findings, highlighting the promise of geometry-tailored antidot waveguides for magnon-based computing applications.

Gelatin production from red tilapia skin fish using high-pressure processing and its characterisations

Enhanced Raman scattering by fast GaN phonon-polaritons

Phonon-polaritons propagating in crystal volume offer the possibility of transferring information throughout matter (via phonons) at high (photon-like) velocity and tunable frequency/wavelength in the far-infrared. However, from the phonon-polariton Raman cross section, the phonon and photon advantages seem mutually exclusive. Either the phonon-polaritons are fast (photon-like) but hardly supported by the lattice (not phonon-like), or they are well supported by the lattice (testified by a high Raman efficiency) but slow (not photon-like). An optimal phonon–photon coupling is currently being searched for in hexagonal GaN by near-forward Raman scattering across parallel crystal faces with an in-plane singular c→-axis. Two accessible phonons, i.e., the ordinary A1 and E1 ones, plus two refractive indices, i.e., the ordinary and extraordinary ones, generate various phonon-polariton candidates. Notably, in perfect forward Raman scattering and in crossed polarizations of the incident (∥c→) and scattered lights, which, altogether, maximizes the transferred wavevector to the crystal at minimum scattering angle, a fast phonon-polariton, stemming from the bottleneck of the E1 dispersion on entry to the deep photon-like regime, is activated. It is well supported by the lattice since its Raman signal is strong and sharp, enhanced by multi-reflection of the laser beam between crystal faces at near-normal incidence. This fast Raman-enhanced phonon-polariton is interesting for infrared photonics in that it cumulates the advantages of a photon (speed) and of a phonon (Raman intensity). Besides, it commutates from a phonon-polariton to a phonon by deviating from normal incidence or by permuting the incident and scattered polarizations, with potential applications as a vibrational switch.

Conflict monitoring with VIIRS Nightfire: the war in Ukraine

Abstract Amid rising geopolitical instability, timely, systematic, and independent monitoring of conflict zones is essential. We show how nighttime thermal anomalies from spaceborne sensors can be combined with boundary data, territorial control vector data, and high-resolution damage assessments to generate indicators of conflict at different levels of analysis. Leveraging the Visible Infrared Imaging Radiometer Suite’s Nightfire product, we extract signals of conflict across Ukraine, tracking the status of heavy industry, delineating the frontline, and detecting urban combat. Although VIIRS data face challenges such as low spatial resolution and susceptibility to atmospheric interference, we find that these can provide valuable insights when paired with supporting geodata. Our results thus support fast, low-cost, and scalable monitoring of conflict zones, enabling timely intelligence in rapidly evolving scenarios.

Triplet exciton energy manipulation toward low turn-on voltage and efficient fluorescent blue organic light-emitting diodes

Fluorescent blue emitters, which are mostly limited to the utilization of singlet excitons, remain the predominant choice in commercial organic light-emitting diodes (OLEDs) owing to the undesirable operational stability of their phosphorescent counterparts. However, the compromised device efficiency and high turn-on voltage (Von) hinder their development. Here, we report an effective interfacial charge-transfer manipulation strategy for realizing efficient blue fluorescent OLEDs. By tailoring the material compositions of the electron transport layer (ETL) to form exciplex excitons at the emitting layer/ETL interface, the energy required for exciton formation can be effectively reduced, which enables increased exciton density at low operating voltages. Furthermore, by employing the anthracene-based material 2-[4–(9,10-Di-2-naphthalenyl-2-anthracenyl)phenyl]-1-phenyl-1H-benziMidazole (ZADN) as the host to promote triplet–triplet upconversion within the EML, low-energy triplet excitons in fluorescent blue OLEDs can be utilized. As a result, the optimized blue fluorescent device, with ZADN as the host material and 4,6-Bis(3,5-di(pyridin-4-yl) phenyl)-2-Methylpyrimidine as the ETL, illustrates a low Von of 2.2 V, a maximum brightness of 53 200 cd/m2, and a high external quantum efficiency (EQE) of 5.1%. Based on this strategy, white-color tandem OLEDs with an EQE of 12% and brightness of 650 cd/m2 at 5 V are achieved.

Empathy for pain in humans and animals differs based on species, psychosocial and cultural factors

The nonreciprocal transmission of magneto-acoustic waves in Ni81Fe19/Cu/Co40Fe40B20 magnetic bilayer

Transmission nonreciprocity is of great significance as it is the defining characteristic of microwave isolators. Combining reciprocal Surface Acoustic Waves (SAWs) with nonreciprocal Spin Waves is an effective way to achieve nonreciprocal transmission. In this work, we investigate the characteristics of SAW–SW coupling in a Ni81Fe19/Cu/Co40Fe40B20 system composed of two ferromagnetic layers separated by a nonmagnetic Cu spacer layer. We use the Vector Network Analyzer to measure the transmission parameters S21 and S12 of the SAW devices. Due to the interlayer dipolar coupling (IDC) between the two ferromagnetic layers, two typical resonance modes are excited: the in-phase acoustic mode (AM) and the out-of-phase optical mode (OM). Because of the helicity mismatch effect and nonreciprocal SW dispersion, the SAW transmissions of both modes exhibit nonreciprocal behavior. Additionally, the nonreciprocity of AM is enhanced due to the spin-rotation coupling (SRC) effect derived from the Cu layer. The magnitude of the transmission nonreciprocity can be regulated by adjusting the Cu layer thickness, which affects the strength of IDC and SRC. We believe that this finding can further the development of magneto-acoustic devices.

Discovery of natural apigenin analogues as lysine-specific demethylase 1 inhibitors against tumoral testicular germ cells

Abstract Testicular germ cell tumors (TGCT) pose a threat to men’s health, discovery of small molecule compounds with potent antiproliferative activity against testicular germ cells is of great significance. Lysine-specific demethylase 1 (LSD1) is overexpressed in tumoral testicular germ cell lines, and it is a promising target for developing agents against TGCT. A series of natural apigenin analogues were evaluated for their inhibitory activity against LSD1, and their structure activity relationships (SARs) were explored. Among them, 8,3’-diprenylapigenin exhibited the most potent inhibitory activity against LSD1 with an IC 50 value of 3.60 µM. 7-hydroxy of 8,3’-diprenylapigenin formed a hydrogen bond with Ala809 of LSD1, demonstrating that 7-hydroxy was a dominant group. In addition, 8,3’-diprenylapigenin reversibly and selectively inhibited LSD1 in a concentration-dependent and time-dependent manner. It inhibited proliferation against tumoral testicular germ cell lines NCCIT and NTERA-2 with IC 50 values of 9.37 µM and 5.26 µM, respectively. Mechanism studies revealed that 8,3’-diprenylapigenin induced the generation of ROS, inhibited the activity of catalase and decreased the level of ATP in NTERA-2 cells. Meanwhile, it also activated the release of LDH, increased the activity of SOD and enhanced the level of MDA in NTERA-2 cells. These findings indicated that 8,3’-diprenylapigenin is a novel reversible LSD1 inhibitor and deserves further exploration to treat testicular germ cell tumors.

Low-damage <i>p</i> -GaN surface for Ohmic contact after passivation layer removal by atomic layer etching

In this work, we present a low-damage p-GaN surface processed by atomic layer etching (ALE), enabling high-performance Ohmic contacts. The mechanism underlying surface modifications introduced by various etching processes were studied in detail. Compared to conventional dry etch, ALE preserves the pristine surface stoichiometry comparable to as-grown p-GaN, effectively suppressing the formation of detrimental surface defects. Crucially, this atomic-level controlled process minimizes the increase in downward band bending and maintains the intrinsic surface electrical properties. Thus, metal contacts fabricated on the ALE-processed p-GaN exhibit an excellent Ohmic behavior. Collectively, these results not only establish low-surface-degradation contacts, but also provide a fundamental understanding required for advancing GaN-based device physics and designs.

Neuroprotective mechanisms of cobalamin in ischemic stroke insights from network pharmacology and molecular simulations

Effects of disorder on the optical properties of deep UV quantum well emitters as assessed by photonic atom probe

The Photonic Atom Probe, a technique allowing the simultaneous, in situ acquisition of photoluminescence within a tomographic atom probe, is applied to the study of AlGaN quantum wells within deep-UV (DUV) separate confinement heterostructures. The analyzed sample exhibits a high degree of compositional and morphological disorder, translating into spatial inhomogeneities and a significant dispersion of photoluminescence emission energy. We show how the proposed in situ correlative microscopy approach can explain different optical emission features in these structures, particularly the distinction between the optical signatures of non-defective quantum well (QW) and QWs located within defective regions. The results, including time-resolved photoluminescence, are interpreted through eight-band k.p calculations, which take as an input to the statistical properties extracted from the atom probe tomography composition maps. This links DUV emission heterogeneity to nanoscale disorder within the same analyzed volume, providing insight relevant to improving multi-QW structures.

An integrated physics-guided machine learning approach for predicting asphalt concrete fracture parameters

Abstract Accurate prediction of fracture energy (G f ) in asphalt mixtures is important for durable asphalt pavements designing. Traditional experimental approaches are reliable but need resources, whereas numerical simulations, such as finite element models (FEM), offer flexibility but needs accurate input parameters and calibration. Recent advances in machine learning offer rapid prediction capabilities; however, interpretability and physical relevance remain challenging in this regard. This study presents a hybrid framework that integrates experimental Single Edge Notch Beam (SENB) tests, finite element simulations, and machine learning models to predict fracture parameters for asphalt mixtures. Experimental testing quantified fracture energy, while FEM simulations replicated the fracture response numerically. Machine learning models, including Linear Regression, Gradient Boosting, and AdaBoost, were trained on mixture properties such as stability, flow, air voids, and Stiffness Modulus at 20 °C (ITSM20) to predict surrogate fracture energy. A novel, dimensionally consistent surrogate equation was proposed to link key mixture properties to fracture energy, validated against both experimental and numerical results. The surrogate model demonstrated best accuracy with a mean relative error compared to experimental data. This novel integrated approach, adopted in this study, provides a practical and physics-guided methodology for rapid and reliable prediction of fracture behavior in asphalt mixtures, bridging experimental observations, numerical simulations, and data-driven machine learning modeling, and offering insights for mixture optimization and pavement design.

Kinetic control of A-site cation disorder and its impact on the ferroelectric phase transition in La2SrSc2O7 layered perovskite oxide

We demonstrate a strategy for tuning the Curie temperature (TC) of hybrid improper ferroelectric La2SrSc2O7, an n = 2 Ruddlesden–Popper-type perovskite oxide. By kinetically controlling the distribution of A-site cations (La/Sr) through different post-sintering cooling rates, TC can be varied widely from ∼400 to ∼700 K. Structural mode analysis reveals that increasing A-site cation disorder weakens ScO6 octahedral deformation and enhances octahedral rotation, thereby stabilizing the polar phase and leading to a higher TC. A linear correlation between TC and A-site cation disorder is established, highlighting A-site cation disorder as a key descriptor for tailoring ferroelectricity in La2SrSc2O7. Consequently, controlling the cooling rate provides an effective, composition-independent pathway for designing hybrid improper ferroelectrics with tunable functionalities, offering a distinct alternative to conventional compositional design.

First molecular confirmations of Anopheles dirus and Anopheles scanloni in Indonesia, with DNA of zoonotic, enzootic and human malarias detected in An. dirus

Abstract Despite Indonesia reporting high numbers of Plasmodium knowlesi malaria cases in North Sumatra Province, the Anopheles mosquito vectors remain unknown. This study identified the Leucosphyrus Group species present in Langkat Regency, North Sumatra, and the Plasmodium species DNA in their heads and thoraces. Mosquitoes collected by human landing catch were morphologically identified and their species identification subsequently confirmed using ITS2 sequencing as well as Dirus Complex (DiCSIP) and Anopheles scanloni -specific PCR. Reverse-transcription real-time and nested PCR assays targeting the 18 S rRNA gene were applied for Plasmodium species detection and identification. Of 597 morphologically identified Leucosphyrus Group mosquitoes, two species of the Dirus Complex were confirmed for the first time in Indonesia: 97.8% of specimens were Anopheles dirus with 2.2% being Anopheles scanloni. Seven An. dirus specimens were Plasmodium -positive, including mixed infections with P. inui , P. knowlesi , and/or P. vivax and one equivocal sample positive for P. coatneyi and P. knowlesi. BLAST analysis indicated possible cross-reactivity of P. fieldi primers with P. inui. This study provides the first molecular confirmation of An. dirus and confirms the presence of An. scanloni , two species of the Dirus Complex in North Sumatra. In addition, it demonstrates the presence of both macaque and human Plasmodium species DNA in An. dirus , suggesting the potential role of this species in zoonotic and human malaria transmission in this Indonesian region.