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Memristive devices have been explored as electronic synaptic devices to mimic biological synapses for developing hardware-based neuromorphic computing systems. However, typical oxide memristive devices suffered from abrupt switching between high and low resistance states, which limits access to achieve various conductance states for analog synaptic devices. Here, we proposed an oxide/suboxide hafnium oxide bilayer memristive device by altering oxygen stoichiometry to demonstrate analog filamentary switching behavior. The bilayer device with Ti/HfO 2 /HfO 2−x (oxygen-deficient)/Pt structure exhibited analog conductance states under a low voltage operation through controlling filament geometry as well as superior retention and endurance characteristics thanks to the robust nature of filament. A narrow cycle-to-cycle and device-to-device distribution were also demonstrated by the filament confinement in a limited region. The different concentrations of oxygen vacancies at each layer played a significant role in switching phenomena, as confirmed through X-ray photoelectron spectroscopy analysis. The analog weight update characteristics were found to strongly depend on the various conditions of voltage pulse parameters including its amplitude, width, and interval time. In particular, linear and symmetric weight updates for accurate learning and pattern recognition could be achieved by adopting incremental step pulse programming (ISPP) operation scheme which rendered a high-resolution dynamic range with linear and symmetry weight updates as a consequence of precisely controlled filament geometry. A two-layer perceptron neural network simulation with HfO 2 /HfO 2−x synapses provided an 80% recognition accuracy for handwritten digits. The development of oxide/suboxide hafnium oxide memristive devices has the capacity to drive forward the development of efficient neuromorphic computing systems.

Bacterial cellulose nanofiber (BCNF) with high thermal stability produced by an ecofriendly process has emerged as a promising solution to realize safe and sustainable materials in the large-scale battery. However, an understanding of the actual thermal behavior of the BCNF in the full-cell battery has been lacking, and the yield is still limited for commercialization. Here, we report the entire process of BCNF production and battery manufacture. We systematically constructed a strain with the highest yield (31.5%) by increasing metabolic flux and improved safety by introducing a Lewis base to overcome thermochemical degradation in the battery. This report will open ways of exploiting the BCNF as a “single-layer” separator, a good alternative to the existing chemical-derived one, and thus can greatly contribute to solving the environmental and safety issues.

Despite the excellent oxygen barrier and biodegradability of polyvinyl alcohol (PVA), its poor physical properties owing to its inherent hydrophilicity limit its application. In this paper, we report a novel surface modification technique for PVA films, involving the control of the predrying conditions (i.e., amount of residual solvent) of the coated PVA film and adjusting the electrospinning process of hydrophobic polycaprolactone (PCL) nanofibers onto the PVA films. The residual solvent of the coated PVA film was varied by changing the predrying time. A shorter predrying time increased the residual solvent content significantly (p < 0.05) and the flexibility of the coated PVA film. Moreover, scanning electron microscopy depicted the improved physical binding of hydrophobic PCL nanofibers to the hydrophilic PVA surface with increased penetration depth to the PVA film with shorter drying times. The PVA/PCL composite films with different predrying times and electrospun PCL nanofibers exhibited an apparent increase in the contact angle from 8.3° to 95.1°. The tensile strength of the pure PVA film increased significantly (p < 0.05) from 7.5 MPa to 77.4 MPa and its oxygen permeability decreased from 5.5 to 1.9 cc/m2·day. Therefore, our newly developed technique is cost-effective for modifying the surface and physical properties of hydrophilic polymers, broadening their industrial applications.

Antarctic lakes are extreme, oligotrophic habitats that contain microbial communities distinct from those of temperate freshwater systems. Our central question was whether these lakes host microbial communities distinct from those of non-Antarctic freshwater systems, and how environmental variability drives community differences among Antarctic lakes themselves. We analyzed the microbial community across five lakes on King George Island via high-throughput sequencing of amplicon sequence variants (ASVs) and biogeochemical profiling. The microbial communities were dominated by Bacteroidota, Actinomycetota, and Pseudomonadota, but varied strongly with environmental gradients such as salinity, sulfate, methane, and organic carbon. Hybrid ASVs, which were ubiquitous in both water and sediment, comprised the majority of sequences and indicate that dispersal processes, alongside environmental filtering, jointly structure lake microbial communities. Functional predictions further revealed lake- and habitat-specific pathways for carbon, nitrogen, and sulfur cycling, linking microbial diversity to ecosystem processes. These findings highlight how Antarctic lake microbes are shaped by both local selective pressures and cross-habitat exchange, providing critical insights into the resilience and vulnerability of polar freshwater ecosystems under climate change.

BackgroundDorsal contour irregularities remain a potential undesirable sequela of rhinoplasty. Use of dorsal onlay grafts can camouflage such irregularities. In this article, a novel technique for dorsal onlay grafting utilizing crushed cartilage mixed with autologous fat is described. This study aims to assess long-term graft retention and aesthetic outcomes with this technique.MethodsPatients with >18-month follow-up who underwent primary open rhinoplasty with the described technique were reviewed. Three-dimensional photographs taken at multiple timepoints were overlaid with volumetric subtraction used to quantify graft retention. The Rhinoplasty module of the FACE-Q was completed by each patient, and the Rhinoplasty Assessment Scale Photographic (RASP) was completed by surgeon reviewers. Pre- and postoperative changes in dorsal height as well as RASP scores were compared with paired t-tests. Changes in BMI, dorsal volume, and dorsal height were compared with linear regression. P values <0.05 were considered significant.ResultsFourteen patients were included, mean age 32. Mean intermediate and final follow-up was 17.8 months and 28.9 months, respectively. There were no statistically significant dorsal height change (mean = 0.0 mm, p = 0.91) and minimal dorsal volume change (mean = 0.02 cm3, range: 0.08 to 0.13). Patients reported a high degree of satisfaction with facial/nasal appearance and psychological/social functioning. There was a statistically significant improvement in RASP scores (p < 0.001) postoperatively.ConclusionCrushed septal cartilage mixed with autologous fat is an effective option for dorsal nasal onlay in rhinoplasty and is associated with excellent graft retention, patient satisfaction, and nasal aesthetics.Level of Evidence IVThis journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266

A novel deployable reflector antenna for small satellites has been designed, fabricated, and experimentally validated. The reflector utilizes a doubly curved flexible surface manufactured from a triaxially woven fabric-reinforced silicone (TWFS) composite. By leveraging high-strain composite materials, the design enables a highly compact stowed configuration while maintaining precise surface accuracy upon deployment. The deployment mechanism is proposed to accommodate a 0.6 m diameter parabolic reflector within a minimal stowed volume, optimizing space efficiency for satellite integration. To validate this concept, a prototype of the reflector antenna has been fabricated and demonstrated the feasibility and effectiveness of the proposed approach.

In this paper, we investigated the membrane fouling mechanism according to the coagulant dosage in algal rich water using a ceramic membrane. The algae that were used in this experiment were Microcystis sp. of cyanobacteria, and the fouling mechanism was analyzed through irrigation and filtration resistance through a constant flow operation. The experimental results showed that the filtration resistance decreased as the coagulant dosage increased, but the irreversibility at above optimum coagulant dosage increased. Additionally, as the coagulant dosage increased, the resistance value due to cake and adsorption contamination decreased, and membrane fouling by adsorption was dominant in comparison with cake fouling and adsorption fouling. The specific cake resistance was decreased as the coagulant dosage increased. The characteristics of the cake layer according to the coagulant dosage were found to loosely form the cake layer by increasing micro-size algae as the coagulant dosage increased. The results of this experiment confirmed the membrane fouling mechanism according to coagulant dosage when the ceramic membrane filtered algal rich water.

A concave profile with class III malocclusion is most often due to a combination of maxillary hypoplasia and mandibular hyperplasia. Surgical correction entails normalization of jaw positions and is more challenging in the setting of concurrent asymmetry and open bite. Treatment should optimize both facial harmony and occlusion. Orthognathic surgery for class III deformities occurs at skeletal maturity and should address all aspects of the condition while preventing unnecessary emotional stress from delayed treatment. In this article, the authors describe the 3-jaw orthognathic surgery technique to address maxillary hypoplasia, mandibular prognathism, open bite, and mandibular asymmetry in a single procedure. The process of preoperative 3-dimensional (3D) virtual surgical planning, detailed surgical technique, fat grafting, and a comparison of preoperative and postoperative 3D aesthetic outcomes is presented. Additionally, a retrospective review of postoperative outcomes of 54 patients who received 3-jaw orthognathic surgery is presented as well.

Fouling mechanisms associated with membrane-based polysaccharide enrichment were determined using a dense ultrafiltration (UF) membrane. Dextran with different molecular weights (MWs) was used as a surrogate for polysaccharides. The influence of dextran MW on fouling mechanisms was quantified using the Hermia model. Flux data obtained with different dextran MWs and filtration cycles were plotted to quantify the more appropriate fouling mechanisms among complete pore blocking, standard pore blocking, intermediate pore blocking, and cake filtration. For 100,000 Da dextran, all four mechanisms contributed to the initial fouling. As the filtration progressed, the dominant fouling mechanism appeared to be cake filtration with a regression coefficient (R2) of approximately 0.9519. For 10,000 Da, the R2 value for cake filtration was about 0.8767 in the initial filtration. Then, the R2 value gradually decreased as the filtration progressed. For 6000 Da, the R2 values of the four mechanisms were very low in the initial filtration. However, as the filtration progressed, the R2 value for cake filtration reached 0.9057. These results clearly show that the fouling mechanism of dense UF membranes during polysaccharide enrichment can be quantified. In addition, it was confirmed that the dominant fouling mechanism can change with the size of the polysaccharide and the duration of filtration.

Communication of goals and realistic expectations between the surgeon and patient is a crucial step of aesthetic rhinoplasty. Three-dimensional (3D) imaging technology allows for sharing of simulated outcomes in the office setting, thereby facilitating this process. This article highlights the use of 3D rhinoplasty simulation in preoperative assessment and the senior author’s preferred surgical technique in open rhinoplasty.