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Metal alloy nanostructures represent a promising platform for next-generation nanophotonic devices, surpassing the limitations of pure metals by offering additional buttons for tailoring their optical properties by compositional variations. While alloyed nanoparticles hold great potential, their scalability and underexplored optical behavior still limit their application. Here, we establish a systematic approach to quantifying the unique optical behavior of the AgAuPd ternary system while providing a direct comparison with its pure constituent metals. Computationally, we analyze their electronic structure and uncover the transition of Pd d states to Pd/Ag hybridized s states in the bulk form, explaining the similar optical properties observed between Pd and AgAuPd. Experimentally, we fabricate pure metal and fully alloyed nanoparticles through solid-state dewetting, a scalable method. During the process, we trace the optical transition in the systems from the initial thin film stage to the final nanoparticle stage with in situ ellipsometry. We reveal the interplay between optical properties influenced by chemical interdiffusion and localized surface plasmon resonance arising from morphological changes with ex situ surface characterizations. Additionally, we analytically implement a metallic layer derived from the ternary system in a trilayer device, resulting in a single-time and irreversible color filter, to demonstrate an application encompassing a lithography-free and cost-effective route for nanophotonic devices.

The introduction of graphene quantum dots (GQDs) in a pentacene field effect transistor (FET) device structure notably improved the on/off ratio, demonstrating a significant memory window. This indicates that GQDs are effective in enhancing carrier retention properties. However, the subsequent introduction of Ag nanoparticles (NPs) between the pentacene layer and GQDs led to a significant decrease in the memory window and a far smaller on/off ratio. This decrease is primarily attributed to an increase in the “off” current, suggesting a detrimental impact of Ag NPs on the device performance. The formation of an interface dipole at the Ag NPs-GQDs interface appears to be the main factor behind this effect, influencing the energy band bending and altering the flat band energy. The integration of Ag NPs into the device not only modifies the threshold voltage and elevates the “off” current through interface dipole effects, but also considerably diminishes the “on” current. This reduction is attributed to the dual influences of reduced carrier concentration resulting from screening phenomena and the obstruction of charge movement caused by interfacial scattering. This twofold effect on both the “on” and “off” currents underscores the complex influence of Ag NPs in regulating the electronic behavior of the FET device. [ABSTRACT FROM AUTHOR]

Tandem organic light‐emitting diodes (OLEDs) are an innovative and promising technology aimed at enhancing the luminance and extending the lifespan of OLED applications. A significant challenge in their development lies in achieving high‐performance charge‐generation layers (CGLs). In this study, the use of a yetterbium‐silver (Yb:Ag) alloy is proposed as an assistant layer within the CGL to improve the injection of generated electrons into the electron transport layer (ETL). This enhancement is confirmed through capacitance–voltage measurements and work function analysis. Moreover, the Yb:Ag layer exhibits exceptional optical transmittance and surface uniformity. Tandem devices fabricated with the Yb:Ag alloy assistant layer exhibited a significant reduction in operating voltage, approximately halving it compared to tandem devices without a metal assistant layer. This resulted in a 2.13‐fold increase in luminous efficiency and a 1.07‐fold improvement in power efficiency compared to a single‐unit device. Thus, the integration of a Yb–Ag alloy as a CGL assistant layer is a promising strategy for improving the performance and viability of tandem OLED technologies, underscoring its potential impact on next‐generation displays and lighting applications. [ABSTRACT FROM AUTHOR]

Nanomaterials are promising alternatives to antibiotics with the potential to handle the menace of emerging multidrug resistance in pathogenic microbes. We report a simple biosynthetic approach to prepare Ag nanoparticles (NPs) with strong antibacterial and antifungal actions by using Piper nigrum fruit extract as a bioreducing agent. The biosynthesized material was characterized by SEM, AFM, TEM, HRTEM, XRD and UV–Visible absorption spectroscopy. SEM, AFM and TEM analyses provided evidence that the average diameter of the Ag NPs was 18 nm, while XRD and HRTEM confirmed the FCC structure of Ag NPs. The biosynthesized Ag NPs demonstrated extremely strong antibacterial activity against Bacillus oceanisediminis and Escherichia coli, and showed extremely strong antifungal action against Schizosaccharomyces pombe, inhibiting their growth at very low concentrations of 3 μ g/mL, 4 μ g/mL and 3 μ g/mL, respectively. The molecular origin of their antibacterial and antifungal activity was studied using various molecular and biochemical assays. The results of these assays revealed a major role for reactive oxygen species (ROS) in the antifungal and antibacterial actions of the biosynthesized Ag NPs. Furthermore, morphological changes in cells and cell wall damage upon Ag NP treatment were observed by scanning electron microscopy. In addition, significant enhancement in protein leakage and fragmentation of DNA was also observed upon treatment of S. pombe, B. oceanisediminis and E. coli with Ag NPs. In conclusion, the observed extremely strong antibacterial and antifungal activities of biosynthesized Ag NPs are due to the oxidative stress triggered by ROS, causing cell wall damage and subsequent protein leakage and DNA fragmentation. We report simple biosynthesis of Ag nanoparticles with strong antibacterial and antifungal actions by using Piper nigrum fruit extract as a bioreducing agent. The biosynthesized Ag nanoparticles demonstrated extremely strong antibacterial activity against Bacillus oceanisediminis and Escherichia coli, and showed extremely strong antifungal action against Schizosaccharomyces pombe, inhibiting their growth at 3, 4 and 3 μ g/mL, respectively. Molecular and biochemical assays revealed major role for Reactive Oxygen Species, while SEM revealed cell wall damage upon Ag nanoparticle treatment. [ABSTRACT FROM AUTHOR]

In recent years, the bacterial synthesis method for nanoparticle production has gained significant attention in research due to its advantages over physical and chemical techniques. In this study, silver-doped graphene oxide (GO) nanoparticles were simultaneously reduced in composite form in a bacterial culture medium. The bacterial synthesis method simultaneously reduced the silver (Ag)-doped graphene oxide (GO: Ag) nanoparticles. The size and shape of the reduced GO:Ag nanoparticles were determined using advanced spectroscopic imaging techniques. Transmission electron microscopy (TEM) images of GO: Ag nanoparticles have reported their approximate dimensions to be around 30-70 nm. Thin films were created by spreading GO:Ag nanoparticles onto glass and p-Si surfaces and drying them at 350 °C. The optical, structural, and electronic properties of these thin films were investigated. The energy band gap value of the film was estimated as 0.75 eV employing the doublebeam UV-Vis spectrophotometer technique to reveal its optical properties. The given value suggests the generation of an electron-rich thin film with a narrow energy band gap. X-ray diffraction (XRD) and Raman techniques were used to explore the structural properties of a GO:Ag semiconductor thin film. The Raman technique yielded peak values for the GO:Ag structure, specifically in the D and G band energy values, at 1348 and 1568 cm-1. Rectifying contacts with a diameter of 1 micrometer were made using Ag metal on this film structure. The current-voltage characteristics of the Ag/GO: Ag/p-Si/Ag structure made after these contacts were investigated. [ABSTRACT FROM AUTHOR]

Alginate dialdehyde-gelatin (ADA-GEL) hydrogels are being studied in bioprinting for their combination of cell adhesion and printability. To incorporate specific functionalities and to improve printability, different additives to ADA-GEL inks are being proposed. Here, a novel type of functional nanoparticles comprising silver patches on silica cores was incorporated into ADA-GEL bioinks. Silver patchy particles (SPPs) were present both on the surface and interior of printed structures. Incorporation of SPPs improved printability of ADA-GEL inks and supported osteosarcoma (MG-63) cells over 7 days of culture. SPPs represent a valuable additive for ADA-GEL hydrogels, being attractive to develop bioinks with advanced functionalities. [ABSTRACT FROM AUTHOR]

Bu araştırma, koruma ve bakım altındaki çocukların gündelik hayatta etkileşimlerini nasıl inşa ettikleri sorusuna yanıt aramıştır. Çalışmanın teorik tartışması, kurum içinde yetişmiş çocukların gündelik hayat performanslarının sosyal sermaye kavramıyla ilişkilendirilmesi ile kurulmuştur. Çalışmada nitel araştırma deseni kullanılmıştır ve çalışma boyunca birkaç farklı yaklaşımla katmanlar halinde ilerlenmiştir. Çalışmada ilk olarak gözlem odaklı otoetnografik bir yaklaşım kullanılmıştır. Ardından örneklem olarak seçilen 6 katılımcı ile sosyoloji bölümü birinci sınıf öğrencileri sınıfta buluşturulmuştur. Araştırmacılar tarafından hazırlanan hikâye çocuklara anlatılmış ve çocuklardan, hikâye ekseninde sosyal ilişki, güven ve toplum kavramlarını betimleyen bir resim çizilmeleri istenmiştir. Bu resimler uzmanların değerlendirmesiyle analize tabi tutularak ikinci katmana geçilmiştir. İkinci katmanda sevgi evlerinden çıkmış çocukların, kurumda yetişme süreçlerine yükledikleri anlamlar tartışılmıştır. Böylece kurumdan bağımsızlaşan 7 katılımcı ile bakım ve koruma altında olmanın sosyal sermayeyle boyutlandırılması yapılmıştır. Çalışmanın en temel sonuçlarından birisi, katılımcıların geçmişlerini bırakmadan kurumda melez bir kimlik inşa etmeleridir. Kurumdan bağımsızlaştıktan sonra gündelik hayatlarında bu melez kimliklerle yaşadıkları tespit edilmiştir.

ASCOT (an acronym derived from Ag-Silver, Copper Oxide, Titanium Oxide) is a user-friendly web tool for digital construction of electrically neutral, energy-minimized spherical nanoparticles (NPs) of Ag, CuO, and TiO2 (both Anatase and Rutile forms) in vacuum, integrated into the Enalos Cloud Platform (https://www.enaloscloud.novamechanics.com/sabydoma/ascot/). ASCOT calculates critical atomistic descriptors such as average potential energy per atom, average coordination number, common neighbour parameter (used for structural classification in simulations of crystalline phases), and hexatic order parameter (which measures how closely the local environment around a particle resembles perfect hexatic symmetry) for both core (over 4 Å from the surface) and shell (within 4 Å of the surface) regions of the NPs. These atomistic descriptors assist in predicting the most stable NP size based on lowest per atom energy and serve as inputs for developing machine learning models to predict the toxicity of these nanomaterials. ASCOT's automated backend requires minimal user input in order to construct the digital NPs: inputs needed are the material type (Ag, CuO, TiO2-Anatase, TiO2-Rutile), target diameter, a Force-Field from a pre-validated list, and the energy minimization parameters, with the tool providing a set of default values for novice users.

Minna Han,1,2,* Zhikuan Xia,2,* Yuekun Zou,3 Ping Hu,4 Mingwang Zhang,5 Xin Yang,3 Ming-Guo Ma,6 Rongya Yang2 1Chinese PLA Medical School, Beijing, 100072, People’s Republic of China; 2Department of Dermatology, The Seventh Medical Center of PLA General Hospital, Beijing, 100072, People’s Republic of China; 3Department of Geriatrics, The Sixth Medical Center of PLA General Hospital, Beijing, 100072, People’s Republic of China; 4Department of Dermatology, Southern Medical Branch of PLA General Hospital, Beijing, 100072, People’s Republic of China; 5Department of Dermatology, Southwest Hospital, Army Medical University, Chongqing, People’s Republic of China; 6College of Materials Science and Technology, Beijing Forestry University, Beijing, 100083, People’s Republic of China*These authors contributed equally to this workCorrespondence: Ming-Guo Ma; Rongya Yang, Email mg_ma@bjfu.edu.cn; yangrya@sina.comBackground: Silver nanomaterials have been widely proven to have antifungal effects against Trichosporon asahii. However, the antifungal mechanism of silver nanomaterials with different morphologies still needs to be explored.Methods: Herein, the antifungal effect of silver nanomaterials against fungus was comparative investigated via silver nanowires and silver nanoparticles with a similar size (30 nm).Results: The optimal antifungal concentration of silver nanowires is 6.24 μg/mL, meanwhile the antifungal concentration of silver nanoparticles is 100 μg/mL. The silver nanowires are significantly superior to the silver nanoparticles. SEM and TEM results indicated that both silver nanoparticles and silver nanowires showed significant morphological changes in the mycelium of the strain, compared with the control. The lower MFC value of silver nanowires indicates good sterilization effect and suitability for eradication treatment, which is slower than that of silver nanoparticles. Moreover, we also investigated the toxicological effects of silver nanoparticles and silver nanowires.Conclusion: We comparative studied and transcriptomic analyzed the antifungal mechanism of Ag nanoparticles and nanowires against Trichosporon asahii. The antifungal effects of silver nanowires were better than the silver nanoparticles, especially in the metabolic processes and oxidative phosphorylation. RNA sequencing results indicated that 15 key targets were selected for experimental verification to interpret the potential antifungal mechanism of Ag nanomaterials against fungus. This work proves that silver nanomaterials with different morphologies have potential applications in fungus therapy such as T. asahii.Keywords: Ag, nanoparticles, nanowires, fungus, antifungal mechanism, Trichosporon asahii, transcriptomics

This study delves into the synthesis and characterization of cellulose nanofibers (NFCs) and their nanobiocomposites incorporating coinage nanoparticles ( Ag,ZnO, and CuO ). NFCs were derived from oil palm empty fruit bunches, yielding fibers with diameters below 5 nm. Silver nanoparticles were synthesized using a reduction method, resulting in spherical particles sized between 10-25 nm. The integration of these nanoparticles into the NFCs matrix was confirmed through SEM, TEM, FT-IR, and XRD analyses. FT-IR spectrum of cellulose nanofibers exhibited peaks at 3399 − 3164 cm^−1 for hydroxyl groups, 2925 − 2812 cm^−1 for the cellulose skeleton, and 1013 cm^−1 for the -C-O-C/-C-O-H group. Significant changes were observed in the spectrum post-nanoparticle addition, notably at 1412 and 1317 cm^−1. SEM analysis revealed microdomains of metallic nanoparticles dispersed within the cellulose nanofiber matrix, contributing to increased molecular orientation and crystallinity index. The crystallinity index of cellulose nanofiber films varied: NFC alone exhibited 76.27%, NFC − ZnO 78.54%, NFC-CuO 77.34%, NFC-Ag 76.29%, and NFC-All 77.95%. These variations directly impacted the mechanical properties of the nanobiocomposites, which exhibited significant improvements. Biological analysis confirmed antimicrobial efficacy against E. coli, S. aureus, and C. albicans due to the presence of metallic nanoparticles. Furthermore, water vapor permeability assessments concluded that the nanobiocomposites are suitable for food packaging applications. These findings underscore the promise of NFC-based nanobiocomposites with coinage nanoparticles for advanced packaging materials. Future research avenues should focus on optimizing nanoparticle loading, refining dispersion techniques, and exploring further applications for these versatile nanobiocomposites.

In facility-based agricultural environments, accurately identifying green tomatoes presents a significant challenge for machine vision systems due to the color similarity between green fruits and background branches and leaves as well as the overlapping occlusion between fruits. To solve this problem, this study constructs and optimizes the Attention Gate (AG) module using Swin-Unet as the baseline model, so that the model can focus on the features related to green tomatoes, suppress irrelevant regions in the background, and effectively enhance the representation of target features. Additionally, in order to optimize the edge smoothing of green tomato segmentation, this study further introduces a Atrous Spatial Pyramid Pooling (ASPP) module, which significantly improves the segmentation accuracy by expanding the feature sensing field and enhancing the multi-scale feature extraction capability. Experimental results on the specially constructed green tomato dataset show that the model achieves 97.5%, 92.4% and 85.9% for Pixel Accuracy (PA), Dice similarity coefficient (Dice) and Intersection over Union (IOU), respectively. The new model outperforms existing partial semantic segmentation models in several key metrics, proving its effectiveness in complex facility environments. This research not only addresses the technical difficulties in recognizing green fruits, but also provides solid technical support for the development and application of intelligent agricultural equipment. The model can be applied to segmentation and recognition of other types of fruits to meet the accuracy and efficiency requirements of green fruit recognition in smart agricultural equipment, which has a broad application prospect. [ABSTRACT FROM AUTHOR]

The dynamic surface self‐reconstruction behavior in local structure correlates with oxygen evolution reaction (OER) performance, which has become an effective strategy for constructing the catalytic active phase. However, it remains a challenge to understand the mechanisms of reconstruction and to accomplish it fast and deeply. Here, we reported a photo‐promoted rapid reconstruction (PRR) process on Ag nanoparticle‐loaded amorphous Ni‐Fe hydroxide nanosheets on carbon cloth for enhanced OER. The photogenerated holes generated by Ag in conjunction with the anodic potential contributed to a thorough reconstruction of the amorphous substrate. The valence state of unsaturated coordinated Fe atoms, which serve as active sites, is significantly increased, while the corresponding crystalline substrate shows little change. The different structural evolutions of amorphous and crystalline substrates during reconstruction lead to diverse pathways of OER. This PRR utilizing loaded noble metal nanoparticles can accelerate the generation of active species in the substrate and increase the electrical conductivity, which provides a new inspiration to develop efficient catalysts via reconstruction strategies. [ABSTRACT FROM AUTHOR]

Because the volatile content of isoamyl alcohol increases sharply on the seventh day of wheat mildew infection, isoamyl alcohol can be used as an early biomarker of wheat mildew infection. Currently, only a few sensors for isoamyl alcohol detection have been reported, and these sensors still suffer from low sensitivity and poor moisture resistance. Herein, the isoamyl alcohol sensitivity of 5 at% Er@LaFeO3 (ELFO) was enhanced by loading Ag nanoparticles on the surface of the ELFO microspheres, while the optimal operating temperature was reduced. The moisture resistance of Ag/ELFO was improved by the incorporation of g-C3N4 nanosheets (NSs) on the surface of Ag/ELFO through electrostatic self-assembly. Given the requirements for practical applications in grain granaries, the sensing behavior of a Ag/ELFO-based sensor incorporating g-C3N4 NSs at 20% relative humidity (RH) was systematically studied, and the sensor demonstrated excellent repeatability, long-term stability, and superior selectivity (791 at 50 ppm) for isoamyl alcohol with a low limit of detection (LOD = 75 ppb). Furthermore, the practical results obtained for wheat at different mildew stages further confirmed the potential of the g-C3N4/Ag/ELFO-based sensor for monitoring the early mildew stage of wheat. This work may offer guidance for enhancing the moisture resistance of gas-sensitive materials through the strategy of employing composite nanomaterials.

This study aims to investigate the NOx/CO reduction characteristics of harmful gases according to the loading amount of active Ag, which plays the most important role in H2-SCR, and the type of support. H2-SCR with Ag loaded on support of TiO2 was reduced to Ag+ at about 140 °C in AgO oxide, and H2-SCR with Ag loaded on support of Al2O3 was reduced to Ag clusters (Agnδ+) at about 260 °C in AgO oxide. Because it is more unstable than AgO oxide, it promoted the chemical reaction of Ag. 0.5Ag/TiO2 H2-SCR showed the highest NOx conversion rate of about 18% at 200 °C, and the window width was also widened. 2Ag/Al2O3 H2-SCR improved the low-temperature activity of the catalyst due to its large specific surface area and the loading amount of active catalyst Ag. Although the harmful gas reduction performance has decreased significantly compared to the active material Pt used in the H2-SCR, research on active materials considering the performance the improvement and economic feasibility must be continued. [ABSTRACT FROM AUTHOR]

Plaque control is especially important during orthodontic treatment because areas of the teeth near brackets and wires are difficult to clean with a toothbrush, resulting in debris buildup of food or dental plaque, thus causing caries and periodontal disease. The objective of this study was to evaluate the antimicrobial properties of silver nanoparticles (AgNPs), titanium dioxide nanoparticles (TiO2NPs), and silver/titanium dioxide nanoparticles (Ag/TiO2NPs), synthesized on the surface of α-alumina ceramic brackets. The AgNPs and TiO2NPs were synthesized by a simple chemical method, and these were characterized by XRD, SEM, and XPS TEM; the antimicrobial activity was tested against Staphylococcus aureus and Escherichia coli by diffusion test. The results of this study demonstrated that by this simple chemical method, silver and titanium dioxide nanoparticles can be synthesized on the surface of α-alumina esthetic brackets, and these NPs possess good antimicrobial activity and the possibility of reducing dental caries, periodontal disease, and white spot generated during orthodontic treatment. [ABSTRACT FROM AUTHOR]

In this study, an efficient, homogeneous, flexible and transparent Ag/Polydimethylsiloxane (PDMS) substrate with an orderly three-dimensional nanopillar structure was proposed. Ag NPs were thermally deposited on the flexible bionic PDMS support obtained by a two-step replication of cicada wings. Scanning electron microscope images reveal when the deposition time was 50 min, Ag NPs of proper size densely covered the entire PDMS nanopillar surface in the Ag-50/PDMS substrate. Both the gaps between the Ag NPs and those between the nanopillars acted as efficient electric field amplifiers. The enhancement factor (EF) of the Ag-50/PDMS substrate was calculated to be 2.89 × 107 by using crystal violet as the probe molecule. The Ag-50/PDMS substrate also exhibited good uniformity and reproducibility with a relative standard deviation of 1.46% and 11.45% respectively. The detection capability of the proposed flexible and transparent Ag-50/PDMS substrate in practical applications was demonstrated by the in-situ detection of 0.1 ppm malachite green on fish surfaces, indicating its great potential in the field of food monitoring. [ABSTRACT FROM AUTHOR]