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• The cobalt-free Mn-LLOs cathode materials with a small amount of Li 2 MnO 3 crystal domain in the bulk structure and gradient doping of Al and Ti elements have been developed. • The batteries with Mn-LLOs cathode deliver the energy density over 600 Wh kg−1, excellent cycle retention of 99.7 % after 800 cycles with low voltage decay of 0.03 mV cycle−1. • The Mn-LLOs cathode materials with bulk structure design and interface regulation can improve the long-time cycling stability of low-cost Mn-based energy storage batteries. The cobalt-free Mn-based Li-rich layered oxide material has the advantages of low cost, high energy density, and good performance at low temperatures, and is the promising choice for energy storage batteries. However, the long-cycling stability of batteries needs to be improved. Herein, the Mn-based Li-rich cathode materials with small amounts of Li 2 MnO 3 crystal domains and gradient doping of Al and Ti elements from the surface to the bulk have been developed to improve the structure and interface stability. Then the batteries with a high energy density of 600 Wh kg−1, excellent capacity retention of 99.7 % with low voltage decay of 0.03 mV cycle−1 after 800 cycles, and good rates performances can be achieved. Therefore, the structure and cycling stability of low voltage Mn-based Li-rich cathode materials can be significantly improved by the bulk structure design and interface regulation, and this work has paved the way for developing low-cost and high-energy Mn-based energy storage batteries with long lifetime. [Display omitted] [ABSTRACT FROM AUTHOR]

Chest radiography, commonly known as CXR, is frequently utilized in clinical settings to detect cardiopulmonary conditions. However, even seasoned radiologists might offer different evaluations regarding the seriousness and uncertainty associated with observed abnormalities. Previous research has attempted to utilize clinical notes to extract abnormal labels for training deep-learning models in CXR image diagnosis. However, these methods often neglected the varying degrees of severity and uncertainty linked to different labels. In our study, we initially assembled a comprehensive new dataset of CXR images based on clinical textual data, which incorporated radiologists’ assessments of uncertainty and severity. Using this dataset, we introduced a multi-relationship graph learning framework that leverages spatial and semantic relationships while addressing expert uncertainty through a dedicated loss function. Our research showcases a notable enhancement in CXR image diagnosis and the interpretability of the diagnostic model, surpassing existing state-of-the-art methodologies. The dataset address of disease severity and uncertainty we extracted is: https://physionet.org/content/cad-chest/1.0/.

Bimetallic Pt-based catalysts, for example, PtZn and PtSn catalysts, have gained significant attention for addressing the poor stability and low selectivity of pristine Pt catalysts over propane dehydrogenation (PDH). However, the structures of the active sites and the corresponding catalytic mechanism of PDH are still elusive. Here, we demonstrate a spatially confined Pt–ZnmOx@RUB-15 catalyst (where “m” is the mole ratio of Zn/Pt and RUB-15 is a layered silica), which exhibited high catalytic activity, ultrahigh selectivity (>99%), and resistance to coking at 550 °C for PDH. Significantly different from the preliminary studies over the PtZn catalysts, through the assistance of quasi-in situX-ray photoelectron spectroscopy (XPS), in situFourier transform infrared spectroscopy (CO-FTIR), in situX-ray absorption spectroscopy (XAS), and CO titration, we discovered that the active sites for PDH were the Pt–ZnOxinterfaces, characterized by a structure of Ptδ+–Zn2+–O–Si. Density functional theory (DFT) calculations showed that Pt atoms positioned at Pt–ZnOxinterfaces with coordinatively unsaturated ZnOxsites facilitate the C–H bond breaking of propane while concurrently suppressing deep dehydrogenation processes. This study suggests that engineering the interfaces of Pt–metal oxides under spatially confined conditions holds promise for developing highly efficient Pt-based catalysts for light alkane dehydrogenation.

Electrical Arc Machining (EAM) presents an efficient technique for processing difficult-to-cut materials such as Inconel 718. However, despite its extremely high machining efficiency, the high energy density in machining makes it difficult to achieve a desirable surface quality that can be compatible with the subsequent cutting process. To solve this issue, this study explores the application of a magnetic field to enhance the performance of Blasting Erosion Arc Machining (BEAM), namely Magnetic Field assisted BEAM (M-BEAM). It leads to an increased Material Removal Rate (MRR) and reductions in both the Tool Wear Ratio (TWR) and the Surface Roughness (represented by Sa) with the increasing magnetic field strength, attributed to the improvements of the arc deflection and molten metal expelling. Moreover, the electromagnetic force is positively correlated with the discharge energy, which can further improve the machining performance of BEAM, especially when the hydrodynamic force is hard to act at large discharge energy. The MRR and Sa are enhanced and reduced by 14.52 % and 41.86 % respectively due to the stronger control effect at large energy. After multi-objective optimization, the optimized MRR in M-BEAM achieves a 9.22 % enhancement and Sa also decreases by 25.96 % and 60.61 % in the roughing and finishing process. This advancement also elevates machining precision as well as mitigates defects such as debris adhesion, overburning, and cracks. Moreover, the recast layer is significantly reduced by 88.59 % and 89.96 %. Consequently, M-BEAM promises extensive applications in aerospace industries for machining Inconel 718 and even for other difficult-to-cut materials with high efficiency and quality.

Dense image prediction tasks demand features with strong category information and precise spatial boundary details at high resolution. To achieve this, modern hierarchical models often utilize feature fusion, directly adding upsampled coarse features from deep layers and high-resolution features from lower levels. In this paper, we observe rapid variations in fused feature values within objects, resulting in intra-category inconsistency due to disturbed high-frequency features. Additionally, blurred boundaries in fused features lack accurate high frequency, leading to boundary displacement. Building upon these observations, we propose Frequency-Aware Feature Fusion (FreqFusion), integrating an Adaptive Low-Pass Filter (ALPF) generator, an offset generator, and an Adaptive High-Pass Filter (AHPF) generator. The ALPF generator predicts spatially-variant low-pass filters to attenuate high-frequency components within objects, reducing intra-class inconsistency during upsampling. The offset generator refines large inconsistent features and thin boundaries by replacing inconsistent features with more consistent ones through resampling, while the AHPF generator enhances high-frequency detailed boundary information lost during downsampling. Comprehensive visualization and quantitative analysis demonstrate that FreqFusion effectively improves feature consistency and sharpens object boundaries. Extensive experiments across various dense prediction tasks confirm its effectiveness.

With prior knowledge of seen objects, humans have a remarkable ability to recognize novel objects using shared and distinct local attributes. This is significant for the challenging tasks of zero-shot learning (ZSL) and fine-grained visual classification (FGVC), where the discriminative attributes of objects have played an important role. Inspired by human visual attention, neural networks have widely exploited the attention mechanism to learn the locally discriminative attributes for challenging tasks. Though greatly promoted the development of these fields, existing works mainly focus on learning the region embeddings of different attribute features and neglect the importance of discriminative attribute localization. It is also unclear whether the learned attention truly matches the real human attention. To tackle this problem, this paper proposes to employ real human gaze data for visual recognition networks to learn from human attention. Specifically, we design a unified Attribute Attention Network (A$^{2}$2Net) that learns from human attention for both ZSL and FGVC tasks. The overall model consists of an attribute attention branch and a baseline classification network. On top of the image feature maps provided by the baseline classification network, the attribute attention branch employs attribute prototypes to produce attribute attention maps and attribute features. The attribute attention maps are converted to gaze-like attentions to be aligned with real human gaze attention. To guarantee the effectiveness of attribute feature learning, we further align the extracted attribute features with attribute-defined class embeddings. To facilitate learning from human gaze attention for the visual recognition problems, we design a bird classification game to collect real human gaze data using the CUB dataset via an eye-tracker device. Experiments on ZSL and FGVC tasks without/with real human gaze data validate the benefits and accuracy of our proposed model. This work supports the promising benefits of collecting human gaze datasets and automatic gaze estimation algorithms learning from human attention for high-level computer vision tasks.

• The intricate composition of the alloy plays a crucial role in generating chemical inhomogeneities, which are pivotal for creating the complex phase structure at the grain boundary. • To harness intergranular precipitation strengthening without compromising ductility, the intergranular nanoprecipitates can consist of multiple phases with varying compositions and structures. Despite differences in crystalline structure and orientation, the transport of dislocation plasticity can be sustained if the crystal planes conducive to dislocation glide are well-matched. • The complex structure of intergranular precipitates can create an undulated stress field near grain boundaries, enhancing the strengthening effect and facilitating multiple slip and cross-slip mechanisms during deformation. • Our material demonstrates a yield strength of approximately 1010 MPa and an ultimate tensile strength of around 1500 MPa, with a notable fracture elongation of 41 %. Precipitation at grain boundaries is typically not regarded as an efficient method for strengthening materials since it can induce grain boundary embrittlement, which detrimentally affects ductility. In this research, we developed a multi-principal element alloy (MPEA) with the composition Cr 30 Co 30 Ni 30 Al 5 Ti 5 (at.%), incorporating both intragranular and intergranular nanoprecipitates. Utilizing multiscale, three-dimensional, and in-situ electron microscopy techniques, coupled with computational simulations, we established that intergranular nanoprecipitation in this material plays a crucial role in enhancing strength and promoting dislocation plasticity. The structure of intergranular nanoprecipitation comprises multiple phases with varying composition and structure. Despite the diversity, the crystal planes conducive to the easy glide of dislocations are well-matched, allowing for the sustained continuity of dislocation slipping across different phase structures. Simultaneously, this structure generates an undulated stress field near grain boundaries, amplifying the strengthening effect and facilitating multiple slip and cross-slip during deformation. Consequently, it promotes the proliferation and storage of dislocations. As a result, our material exhibits a yield strength of approximately 1010 MPa and an ultimate tensile strength of around 1500 MPa, accompanied by a significant fracture elongation of 41 %. Our findings illuminate the potential for harnessing intergranular nanoprecipitation to optimize the strength-ductility trade-off in MPEAs, emphasizing the strategy of leveraging complex compositions for the design of sophisticated functional microstructures. [Display omitted] [ABSTRACT FROM AUTHOR]

Unconventional 1T′-phase transition metal dichalcogenides (TMDs) have aroused tremendous research interest due to their unique phase-dependent physicochemical properties and applications. However, due to the metastable nature of 1T′-TMDs, the controlled synthesis of 1T′-TMD monolayers (MLs) with high phase purity and stability still remains a challenge. Here we report that 4H-Au nanowires (NWs), when used as templates, can induce the quasi-epitaxial growth of high-phase-purity and stable 1T′-TMD MLs, including WS2, WSe2, MoS2and MoSe2, via a facile and rapid wet-chemical method. The as-synthesized 4H-Au@1T′-TMD core–shell NWs can be used for ultrasensitive surface-enhanced Raman scattering (SERS) detection. For instance, the 4H-Au@1T′-WS2NWs have achieved attomole-level SERS detections of Rhodamine 6G and a variety of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins. This work provides insights into the preparation of high-phase-purity and stable 1T′-TMD MLs on metal substrates or templates, showing great potential in various promising applications.

Interfacial strain engineering can induce structural transformation and introduce new physical properties into materials, which is an effective method to prepare new multifunctional materials. However, interfacial strain has a limited spatial impact size. For example, in 2D thin films, the critical thickness of biaxial strain is typically less than 20 nm, which is not conducive to the maintenance of a strained structure and properties in thick film materials. The construction of a 3D interface can solve this problem. The large lattice mismatch between the BaZrO3thin film and the substrate can induce the out-of-phase boundary (OPB) structure, which can extend along the thickness direction with the stacking of atoms. The lattice distortion at the OPB structure can provide a clamping effect for each layer of atoms, thus expanding the spatial influence range of biaxial strain. As a result, the uniform in-plane strain distribution and strain-induced ferroelectricity (Pr= 13 μC/cm2) are maintained along the thickness direction in BaZrO3films.

An in situformed IrOx(x≤ 2) layer driven by anodic bias serves as the essential active site of Ir-based materials for oxygen evolution reaction (OER) electrocatalysis. Once being confined to atomic thickness, such an IrOxlayer possesses both a favorable ligand effect and maximized active Ir sites with a lower O-coordination number. However, limited by a poor understanding of surface reconstruction dynamics, obtaining atomic layers of IrOxremains experimentally challenging. Herein, we report an idea of material design using intermetallic IrVMn nanoparticles to induce in situformation of an ultrathin IrOxlayer (O-IrVMn/IrOx) to enable the ligand effect for achieving superior OER electrocatalysis. Theoretical calculations predict that a strong electronic interaction originating from an orderly atomic arrangement can effectively hamper the excessive leaching of transition metals, minimizing vacancies for oxygen coordination. Linear X-ray absorption near edge spectra analysis, extended X-ray absorption fine structure fitting outcomes, and X-ray photoelectron spectroscopy collectively confirm that Ir is present in lower oxidation states in O-IrVMn/IrOxdue to the presence of unsaturated O-coordination. Consequently, the O-IrVMn/IrOxdelivers excellent acidic OER performances with an overpotential of only 279 mV at 10 mA cm–2and a high mass activity of 2.3 A mg–1at 1.53 V (vs RHE), exceeding most Ir-based catalysts reported. Moreover, O-IrVMn/IrOxalso showed excellent catalytic stability with only 0.05 at. % Ir dissolution under electrochemical oxidation, much lower than that of disordered D-IrVMn/IrOx(0.20 at. %). Density functional theory calculations unravel that the intensified ligand effect optimizes the adsorption energies of multiple intermediates involved in the OER and stabilizes the as-formed catalytic IrOxlayer.

The recent discovery of superconductivity in La3Ni2O7−δunder high pressure with a transition temperature around 80 K (ref. 1) has sparked extensive experimental2–6and theoretical efforts7–12. Several key questions regarding the pairing mechanism remain to be answered, such as the most relevant atomic orbitals and the role of atomic deficiencies. Here we develop a new, energy-filtered, multislice electron ptychography technique, assisted by electron energy-loss spectroscopy, to address these critical issues. Oxygen vacancies are directly visualized and are found to primarily occupy the inner apical sites, which have been proposed to be crucial to superconductivity13,14. We precisely determine the nanoscale stoichiometry and its correlation to the oxygen K-edge spectra, which reveals a significant inhomogeneity in the oxygen content and electronic structure within the sample. The spectroscopic results also reveal that stoichiometric La3Ni2O7has strong charge-transfer characteristics, with holes that are self-doped from Ni sites into O sites. The ligand holes mainly reside on the inner apical O and the planar O, whereas the density on the outer apical O is negligible. As the concentration of O vacancies increases, ligand holes on both sites are simultaneously annihilated. These observations will assist in further development and understanding of superconducting nickelate materials. Our imaging technique for quantifying atomic deficiencies can also be widely applied in materials science and condensed-matter physics.

The redox transition between iron and its oxides is of the utmost importance in heterogeneous catalysis, biological metabolism, and geological evolution. The structural characteristics of this reaction may vary based on surrounding environmental conditions, giving rise to diverse physical scenarios. In this study, we explore the atomic-scale transformation of nanosized Fe3O4under ambient-pressure H2gas using in-situ environmental transmission electron microscopy. Our results reveal that the internal solid-state reactions dominated by iron diffusion are coupled with the surface reactions involving gaseous O or H species. During reduction, we observe two competitive reduction pathways, namely Fe3O4→ FeO → Fe and Fe3O4→ Fe. An intermediate phase with vacancy ordering is observed during the disproportionation reaction of Fe2+→ Fe0+ Fe3+, which potentially alleviates stress and facilitates ion migration. As the temperature decreases, an oxidation process occurs in the presence of environmental H2O and trace amounts of O2. A direct oxidation of Fe to Fe3O4occurs in the absence of the FeO phase, likely corresponding to a change in the water vapor content in the atmosphere. This work elucidates a full dynamical scenario of iron redox under realistic conditions, which is critical for unraveling the intricate mechanisms governing the solid–solid and solid–gas reactions.

The oriented attachment (OA) of nanoparticles (NPs) is an important crystal growth mechanism in many materials. However, a comprehensive understanding of the atomic-scale alignment and attachment processes is still lacking. We conducted in situatomic resolution studies using high-resolution transmission electron microscopy to reveal how two Pt NPs coalesce into a single particle via OA, which involves the formation of atomic-scale links and a grain boundary (GB) between the NPs, as well as GB migration. Density functional theory calculations showed that the system energy changes as a function of the number of disconnections during the coalescence process. Additionally, the formation and annihilation processes of disconnection are always accompanied by the cooperative reorientation motion of atoms. These results further elucidate the growth mechanism of OA at the atomic scale, providing microscopic insights into OA dynamics and a framework for the development of processing strategies for nanocrystalline materials.

Using nanobubbles as geometrical confinements, we create a thin water film (∼10 nm) in a graphene liquid cell and investigate the evolution of its instability at the nanoscale under transmission electron microscopy. The breakdown of the water films, resulting in the subsequent formation and growth of nanodroplets, is visualized and generalized into different modes. We identified distinct droplet formation and growth modes by analyzing the dynamic processes involving 61 droplets and 110 liquid bridges within 31 Graphene Liquid Cells (GLCs). Droplet formation is influenced by their positions in GLCs, taking on a semicircular shape at the edge and a circular shape in the middle. Growth modes include liquid mass transfer driven by Plateau-Rayleigh instability and merging processes in and out-of-plane of the graphene interface. Droplet growth can lead to the formation of liquid bridges for which we obtain multiview projections. Data analysis reveals the general dynamics of liquid bridges, including drawing liquids from neighboring residual water films, merging with surrounding droplets, and merging with other liquid bridges. Our experimental observations provide insights into fluid transport at the nanoscale.

Proton exchange membrane water electrolysis (PEMWE) is promising for the sustainable and scalable production of green hydrogen, yet it is now technologically limited by the high loading of precious Ir in the anodic catalyst layer (CL). Herein, we report a kind of anodic CL composed of hierarchical IrRu sub-nanosheets on nanowires for boosting the operational efficiency of PEM electrolyzers. Integrating this hierarchical CL into PEMWE with a low Ir loading of 0.35 mgIrcm−2, we demonstrated an outstanding water electrolysis performance—a hydrogen production current density of 1.0 A cm−2at 1.65 V, along with a high overload current density of 6.0 A cm−2. In particular, the PEMWE could operate stably at 2.0 A cm−2for more than 240 h. We further demonstrated the application of our designed PEMWE in a commercial hydrogen generator with a high H2generation rate of ∼300 mL min−1.

Potassium–sulfur (K–S) batteries are severely limited by the sluggish kinetics of the solid-phase conversion of K2S3/K2S2to K2S, the rate-determining and performance-governing step, which urgently requires a cathode with facilitated sulfur accommodation and improved catalytic efficiency. To this end, we leverage the orbital-coupling approach and herein report a strong d−π coupling catalytic configuration of single-atom Co anchored between two alkynyls of graphdiyne (Co-GDY). The d−π orbital coupling of the Co–C4moiety fully redistributes electrons two-dimensionally across the GDY, and as a result, drastically accelerates the solid-phase K2S3/K2S2to K2S conversion and enhances the adsorption of sulfur species. Applied as the cathode, the S/Co-GDY delivered a record-high rate performance of 496.0 mAh g–1at 5 A g–1in K–S batteries. In situand ex situcharacterizations coupling density functional theory (DFT) calculations rationalize how the strong d−π orbital coupling of Co–C4configuration promotes the reversible solid-state transformation kinetics of potassium polysulfide for high-performance K–S batteries.

Transition metal oxides display rich functionalities, but intricate internal degrees of freedom pose a challenge to understanding phase diagrams as a road map for material exploration. Here, the order of orbital energy level (ELO) as a physical principle of phase diagrams is introduced and demonstrated to be effective by employing La0.67Sr0.33-MnO3(LSMO) oxides. A phase diagram of LSMO associated with the oxygen content and strain is built combining DFT calculations and experiments, in which the structural stability is closely related to ELO. We thereby find a new phase with four-fold oxygen ordering as a result of ELO evolution. More important, orbital elasticity law, describing the degree of orbital splitting, is proposed to clarify the origin of ELO evolution, with the objective of design of functional oxides with specific functionality. This work broadens the means of performance modulation in the field of materials science and opens up an opportunity for phase diagram prediction from an orbital perspective.

The intrinsic luminescent properties of waterborne polyurethane (WPU) as an industrial-scale nonconjugated polymer and the role of side groups in its intrinsic luminescence remain unclear and require further exploration. In this work, a series of WPUs with different side carboxyl contents were prepared, which exhibit clusterization-triggered emission (CTE) characteristics. The carboxyl group of the side carboxyl groups strengthened the hydrogen bond, electron overlap between lone pairs and π electrons, and dipole–dipole and n–π* interactions, thereby enhancing the emission intensity. Furthermore, leveraging the clusteroluminescence characteristics of WPU, various applications have been developed, including explosive and Fe3+detection, damage tracing, and stretch fluorescence change. This work not only enhances our understanding of the clusteroluminescence mechanism but also provides an effective approach for designing and operating nonconjugated fluorescent materials.

A green and eco-friendly solvothermal approach is proposed for the synthesis of carbon quantum dots (CQDs) from watermelon rind. The as-prepared CQDs exhibited superior teal fluorescence in aqueous solutions, with a quantum yield of 13.9%. The CQDs and rhodamine B (RhB) were demonstrated to selectively react with Fe3+and Cu2+, leading to a fluorescence (FL) quenching effect, which was successfully used for constructing “double-response-off” type ratiometric FL probes. A comparative study was conducted to assess the sensitivity and accuracy of ratiometric fluorescent probes, specifically those based on CQDs alone and in combination with RhB, for the selective detection of Fe3+and Cu2+. By plotting the ratio of the differential fluorescence (ΔF) signals of CQDs to that of RhB against the practical application analyte concentration, the detection limits for Fe3+(1.75 μM) and Cu2+(0.43 μM) were markedly improved. The quenching mechanism was further explored, and the detection of Fe3+and Cu2+in surface water was demonstrated, showcasing the potential of efficient and effective nanosensors based on a static quenching effect. Futhermore, the addition of ascorbic acid can restore the fluorescence quenched by Fe3+. Therefore, in the presence of copper and iron, the ratiometric probe can demonstrate the ability to identify two different metals.

Ependymal cells line the wall of cerebral ventricles and ensure the unidirectional cerebrospinal fluid (CSF) flow by beating their motile cilia coordinately. The ependymal denudation or ciliary dysfunction causes hydrocephalus. Here, we report that the deficiency of regulator of G-protein signaling 22 (RGS22) results in severe congenital hydrocephalus in both mice and rats. Interestingly, RGS22 is specifically expressed in ependymal cells within the brain. Using conditional knock-out mice, we further demonstrate that the deletion of Rgs22 exclusively in nervous system is sufficient to induce hydrocephalus. Mechanistically, we show that Rgs22 deficiency leads to the ependymal denudation and impaired ciliogenesis. This phenomenon can be attributed to the excessive activation of lysophosphatidic acid receptor (LPAR) signaling under Rgs22-/-condition, as the LPAR blockade effectively alleviates hydrocephalus in Rgs22-/-rats. Therefore, our findings unveil a previously unrecognized role of RGS22 in the central nervous system, and present RGS22 as a potential diagnostic and therapeutic target for hydrocephalus.

Monoatomic-layered carbon materials, such as graphene1and amorphous monolayer carbon2,3, have stimulated intense fundamental and applied research owing to their unprecedented physical properties and a wide range of promising applications4,5. So far, such materials have mainly been produced by chemical vapour deposition, which typically requires stringent reaction conditions compared to solution-phase synthesis. Herein, we demonstrate the solution preparation of free-standing nitrogen-doped amorphous monolayer carbon with mixed five-, six- and seven-membered (5-6-7-membered) rings through the polymerization of pyrrole within the confined interlayer cavity of a removable layered-double-hydroxide template. Structural characterizations and first-principles calculations suggest that the nitrogen-doped amorphous monolayer carbon was formed by radical polymerization of pyrrole at the α, β and N sites subjected to confinement of the reaction space, which enables bond rearrangements through the Stone–Wales transformation. The spatial confinement inhibits the C–C bond rotation and chain entanglement during polymerization, resulting in an atom-thick continuous amorphous layer with an in-plane π-conjugation electronic structure. The spatially confined radical polymerization using solid templates and ion exchange strategy demonstrates potential as a universal synthesis approach for obtaining two-dimensional covalent networks, as exemplified by the successful synthesis of monolayers of polythiophene and polycarbazole.

Electrical arc machining (EAM) is an efficient process for machining difficult-to-cut materials. However, limited research has been conducted on sloped surface machining within this context, constraining the further application for complex components. This study conducts bevel machining experiments, pointing out that the surface quality becomes unsatisfactory with the increasing bevel angle. The discharge condition is counted and analyzed, while the flow field and the removed particle movement of the discharge gap are simulated, demonstrating the primary factor contributing to the degradation of surface quality, namely the loss of flushing. This weakens both the plasma control effect and debris evacuation, leading to the poor discharge condition. To address this issue, the magnetic field is implemented in blasting erosion arc machining (BEAM). The application of a magnetic field effectively regulates the arc plasma, enhances debris expulsion, and significantly improves the discharge conditions, resulting in a smoother and more uniform sloped surface with a reduced recast layer thickness. This approach provides the possibility of applying BEAM to complex parts made of difficult-to-cut materials in aerospace and military industries.

Robust ferroelectricity in nanoscale fluorite oxide-based thin films enables promising applications in silicon-compatible non-volatile memories and logic devices. However, the polar orthorhombic (O) phase of fluorite oxides is a metastable phase that is prone to transforming into the ground-state non-polar monoclinic (M) phase, leading to macroscopic ferroelectric degradation. Here we investigate the reversibility of the O–M phase transition in ZrO2nanocrystals via in situ visualization of the martensitic transformation at the atomic scale. We reveal that the reversible shear deformation pathway from the O phase to the monoclinic-like (M′) state, a compressive-strained M phase, is protected by 90° ferroelectric–ferroelastic switching. Nevertheless, as the M′ state gradually accumulates localized strain, a critical tensile strain can pin the ferroelastic domain, resulting in an irreversible M′–M strain relaxation and the loss of ferroelectricity. These findings demonstrate the key role of ferroelastic switching in the reversibility of phase transition and also provide a tensile-strain threshold for stabilizing the metastable ferroelectric phase in fluorite oxide thin films.

The potential of 3D bioprinting in tissue engineering and regenerative medicine is enormous, but its implementation is hindered by the reliance on high-strength materials, which restricts the use of low-viscosity, biocompatible materials. Therefore, a major challenge for incorporating 3D bioprinting into tissue engineering is to develop a novel bioprinting platform that can reversibly provide high biological activity materials with a structural support. This study presents a room temperature printing system based on GelMA combined with carrageenan to address this challenge. By leveraging the wide temperature stability range and lubricating properties of carrageenan the room temperature stability of GelMA could be enhanced, as well as creating a solid ink to improve the performance of solid GelMA. Additionally, by utilizing the solubility of carrageenan at 37 °C, it becomes possible to prepare a porous GelMA structure while mimicking the unique extracellular matrix properties of osteocytes through residual carrageenan content and amplifying BMSCs’ osteogenesis potential to some extent. Overall, this study provides an innovative technical platform for incorporating a low-viscosity ink into 3D bioprinting and resolves the long-standing contradiction between material printing performance and biocompatibility in bioprinting technology.

BackgroundSpinal cord damage is a feature of many spinocerebellar ataxias (SCAs), but well-powered in vivo studies are lacking and links with disease severity and progression remain unclear. Here we characterise cervical spinal cord morphometric abnormalities in SCA1, SCA2, SCA3 and SCA6 using a large multisite MRI dataset.MethodsUpper spinal cord (vertebrae C1–C4) cross-sectional area (CSA) and eccentricity (flattening) were assessed using MRI data from nine sites within the ENIGMA-Ataxia consortium, including 364 people with ataxic SCA, 56 individuals with preataxic SCA and 394 nonataxic controls. Correlations and subgroup analyses within the SCA cohorts were undertaken based on disease duration and ataxia severity.ResultsIndividuals in the ataxic stage of SCA1, SCA2 and SCA3, relative to non-ataxic controls, had significantly reduced CSA and increased eccentricity at all examined levels. CSA showed large effect sizes (d>2.0) and correlated with ataxia severity (r<−0.43) and disease duration (r<−0.21). Eccentricity correlated only with ataxia severity in SCA2 (r=0.28). No significant spinal cord differences were evident in SCA6. In preataxic individuals, CSA was significantly reduced in SCA2 (d=1.6) and SCA3 (d=1.7), and the SCA2 group also showed increased eccentricity (d=1.1) relative to nonataxic controls. Subgroup analyses confirmed that CSA and eccentricity are abnormal in early disease stages in SCA1, SCA2 and SCA3. CSA declined with disease progression in all, whereas eccentricity progressed only in SCA2.ConclusionsSpinal cord abnormalities are an early and progressive feature of SCA1, SCA2 and SCA3, but not SCA6, which can be captured using quantitative MRI.

Background: Certain widely used pathological outcome prediction models that were developed in tertiary centers tend to overpredict outcomes in the community setting; thus, the Michigan Urological-Surgery Improvement Collaborative (MUSIC) model was developed in general urology practice to address this issue. Additionally, the development of these models involved a relatively small proportion of Black men, potentially compromising the accuracy of predictions in this patient group. We tested the validity of the MUSIC and three widely used nomograms to compare their overall and race-stratified predictive performance. Methods: We extracted data from 4139 (1138 Black) men from the Shared Equal Access Regional Cancer Hospital (SEARCH) database of the Veterans Affairs health system. The predictive performance of the MUSIC model was compared to the Memorial-Sloan Kettering (MSK), Briganti-2012, and Partin-2017 models for predicting lymph-node invasion (LNI), extra-prostatic extension (EPE), and seminal vesicle invasion (SVI). Results: The median PSA of Black men was higher than White men (7.8 vs. 6.8 ng/ml), although they were younger by a median of three years and presented at a lower-stage disease. MUSIC model showed comparable discriminatory capacity (AUC:77.0%) compared to MSK (79.2%), Partin-2017 (74.6%), and Briganti-2012 (76.3%), with better calibration for LNI. AUCs for EPE and SVI were 72.7% and 76.9%, respectively, all comparable to the MSK and Partin models. LNI AUCs for Black and White men were 69.6% and 79.6%, respectively, while EPE and SVI AUCs were comparable between races. EPE and LNI had worse calibration in Black men. Decision curve analysis showed MUSIC superiority over the MSK model in predicting LNI, especially among Black men. Conclusion: Although the discriminatory performance of all models was comparable for each outcome, the MUSIC model exhibited superior net benefit to the MSK model in predicting LNI outcomes among Black men in the SEARCH population.

We studied the stability mechanism of Ti-doped Ni-rich cathodes given the strong Ti–O bonding. Ti doped LiNi0.9Mn0.1O2cathode shows superior cycling stability not only due to the in-situ formed Ti-rich layer, but also owing to the hindered phase transition in bulk.

By leveraging standard IT virtualization technology and Commercial-Off-The-Shelf (COTS) servers, Network Function Virtualization (NFV) decouples network functions from proprietary hardware devices for flexible service provisioning. But the potential of NFV is significantly limited by its performance inefficiency. With the unparalleled advantages of multi-core parallelism and high memory bandwidth, Graphics Processing Units (GPUs) are regarded as a promising way to accelerate Virtualized Network Functions (VNF). However, the special architecture of GPU brings new challenges to task scheduling and resource allocation. To this end, we propose a GPU oriented spatio-temporal sharing framework for NFV called Gost, aiming for GPU based VNF performance promotion. The execution order and GPU resource allocation (i.e., the number of threads) are considered in task scheduling to minimize the end-to-end latency for VNF flows. First, we formulate the task scheduling problem into a nonlinear programming form, and then transform it into an equivalent Integer Linear Programming (ILP) form. The problem is proved as NP-hard. We customize the classical list scheduling algorithm and propose a List Scheduling based Spatio-Temporal GPU sharing strategy (LSSTG), whose achievable worst-case performance is also formally analyzed. We practically implement Gost prototype, based on which extensive experiments verify the high performance efficiency of LSSTG compared to state-of-the-art in terms of latency and throughput.