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Enhanced catalytic activity for emission control of CO and NH3 by solid-state impregnation of Ag on γ-Al2O3 support
No full textWhile metallic Ag species are known for superior active sites for oxidation reactions of NH3 and CO compared to Ag oxides, achieving precise control over the surface Ag phase through the conventional wet method has been a significant challenge, primarily due to the strong metal-support interaction on the γ-Al2O3 surface. This study unveiled that the chemical state of the Ag precursor before calcination is a crucial factor in determining these interactions, affecting the surface Ag phase. We found that the ionic state of Ag in aqueous solution, via a conventional preparation method, actively forms a strong bonding with surface hydroxyl groups on γ-Al2O3, leading to the formation of well-dispersed Ag oxide species unfavorable for catalytic reactivity. By employing the solid-state impregnation method, we successfully suppressed this metal-support interaction, favoring the formation of metallic Ag nanoparticles. The resultant catalyst exhibited remarkable oxidation activities of CO or NH3, outperforming conventional impregnated catalysts. TEM and UV–vis spectroscopy confirmed that the Ag/γ-Al2O3 with solid-state impregnation exhibited pronounced metallic characteristics of Ag species, even at low Ag loadings.FALSEsciescopu
A nonlocal metasurface for optical edge detection in the far-field
No full textRecent studies on nonlocal metasurfaces have shown possibilities of optical image processing, such as edge detection, without the need for Fourier optics and have significantly reduced the form factor. However, the analog edge detection using nonlocal metasurfaces still requires the use of multiple lenses to image the edge-enhanced results, and the edge-detected image generally suffers from image distortion originating from the free space propagation before reaching the detector otherwise. In this work, we propose a nonlocal metasurface that not only enhances the edge features but also delivers them to the far-field with considerably less distortion by combining the conventional edge detection metasurface with a uniaxial slab that has a transfer function of the free space with a negative propagation length. This space expander cancels out the diffraction of the edge-enhanced image that occurs during the free space propagation, the thickness of which reaches several orders of magnitude larger than the slab thickness. This nonlocal metasurface for the far-field edge detection will open a path towards compact optical systems for high-quality analog image processing.TRUEsciescopu
Generalized ice models in two- and three-dimensional lattices: Residual entropies and phase transitions
No full textWe investigate a family of generalized ice models, employing Wang-Landau Monte Carlo sampling to characterize their residual entropies and thermodynamic behaviors. For the edge-sharing square-ice model, we derive an exact residual-entropy formula. Pauling's approximation yields semiquantitative agreement for corner-sharing systems, typically underestimating residual entropy, but notably overestimating it in the corner-sharing hexagonal-ice model. Thermodynamic analysis reveals that the models with extensive residual entropy exhibit Schottky-type specific heat, without indications of phase transitions, whereas the edge-sharing square-ice and face-sharing cubic-ice models show signatures of continuous and first-order finite-temperature phase transitions, respectively. These results demonstrate how ice-rule constraints give rise to diverse thermodynamic phenomena and offer insights into related frustrated systems.FALSEsciescopu
High-Load Capable Soft Tactile Sensors: Incorporating Magnetorheological Elastomer for Accurate Contact Detection and Classification of Asymmetric Mechanical Components
No full textSoft tactile sensors are soft and sufficiently flexible for attachment to a robot's gripper to enhance human-like sensory capabilities. However, existing tactile sensors exhibit large size and a limited force measurement range. This article presents a novel design of a new soft tactile sensor for a robotic gripper, incorporating a sandwich-like multilayered structure, together with a deep learning (DL) model, which overcomes the limitations of traditional sensors. The structure consists of three distinct layers: a 15 wt% iron magnetorheological elastomer, a flexible printable circuit board layer equipped with three-dimensional Hall sensors (TLE493D; Infineon), and permanent magnets. Additionally, a multilayer perceptron network that can classify the loading state is adopted for the DL model. This new tactile sensor is capable of performing three distinct functions simultaneously: measurement of normal forces up to 3.73 kgf, identification of the precise location of force occurrence by subdivision into intervals of 2.5 mm, and differentiation between a wide (≈8 mm) and narrow (≈2 mm) contacted surface area. This newly developed soft tactile sensor has considerable potential for improvement in the performance of robotic grippers through its high accuracy, resolution, and large measurement range, as demonstrated by experimentation with the sensor attached to a real gripper. © 2024 The Author(s). Advanced Intelligent Systems published by Wiley-VCH GmbH.TRUEsciescopu
Reaction Profile Forecasting by Artificial Data Generation for Wittig-Type Geminal Bromofluoroolefination
No full textMachine learning (ML) is emerging as a valuable tool in organic synthesis for reaction design and prediction. In recent studies, the ML approach for reaction development using big data with many features provided the best reaction conditions for optimal yields and stereoselectivities. However, the preparation of large data sets is often challenging, especially for nonspecialists such as experimental scientists. In this study, we developed simple ML models for predicting reaction profiles of our geminal bromofluoroolefination with a minimal data set containing only readily accessible features, including 13C NMR chemical shifts of the reacting sites and Verloop’s Sterimol values. Notably, the model’s efficiency was significantly enhanced through an underutilized tabular augmentation method. By fitting the sparse data points to proper sigmoidal curves, we generated augmented data sets that improved the predicting ability of the feed-forward neural network (FNN). Furthermore, the combination of this augmentation technique with a conditional tabular generative adversarial network (CTGAN) synergistically refined the model’s performance. Our achievement highlights the utility of tailored augmentation strategies as a potential solution for the limitations posed by small experimental data sets in ML-driven reaction development. © 2025 American Chemical Society.FALSEsciescopu
Cdc42 defect reveals insights into microvilli organization and function in T cell immunity
No full textMicrovilli on T cells differ from those on epithelial cells, exhibiting filopodia-like characteristics that facilitate the clustering of molecules essential for sensing and cell migration. Recently, they have also been recognized as the structures from which T cell immunological synaptosomes (TIS) are released. In this study, we examined a key determinant of microvilli organization during T cell development and explored the functional roles of these structures, particularly in relation to T cell behaviors. During thymocyte maturation, single-positive thymocytes were found to develop more and longer microvilli than double-positive thymocytes. However, the deletion or inhibition of Cdc42, a small Rho family protein, significantly reduced both the number and length of microvilli in single-positive thymocytes, leading to decreased cell mass. This reduction in microvilli correlates with a decrease in antigen recognition, leading to diminished T cell activation and adhesion, as well as reduced TIS production, while intrinsic migratory properties remain unaffected. These findings highlight the filopodia-like characteristics of T cell microvilli. In this context, Cdc42 contributes significantly to microvilli formation, thereby shaping T cell function.TRUEsciescopu
Prevention of radiotherapy-induced pro-tumorigenic microenvironment by SFK inhibitors
No full textBackground: Radiotherapy is a widely employed technique for eradication of tumor using high-energy beams, and has been applied to approximately 50% of all solid tumor patients. However, its non-specific, cell-killing property leads to inevitable damage to surrounding normal tissues. Recent findings suggest that radiotherapy-induced tissue damage contributes to the formation of a pro-tumorigenic microenvironment. Methods: Here, we utilized two mouse strains and two organ-targeted radiotherapy models to uncover the mechanisms underlying the development of the radiotherapy-induced microenvironment. Results: Radiotherapy-induced tissue damage stimulates infiltration of monocyte-derived macrophages and their differentiation into M2 macrophages, ultimately leading to fibrosis and the formation of a pro-tumorigenic microenvironment. Notably, SRC family kinases (SFKs) emerged as crucial factors in the formation of the radiotherapy-induced pro-tumorigenic microenvironment. SFKs activation in epithelial cells and fibroblasts was triggered by direct exposure to irradiation or M2 macrophage cytokines. Remarkably, the administration of SFK-targeted inhibitors reversed myofibroblast activation, effectively ameliorating fibrosis and the pro-tumorigenic microenvironment in radiated tissues. Further, combined administration of radiotherapy and SFK-targeted inhibitors significantly enhanced the survival of tumor-bearing mice. Conclusions: Reshaping the tissue microenvironment by targeting SFKs is a potential strategy for preventing metastasis and recurrence following radiotherapy. The finding that clinically imperceptible damage can trigger a pro-tumorigenic microenvironment suggests the need for combining SFK-targeted inhibitors with radiotherapy. © The author(s).TRUEsciescopu
A simple, versatile approach for coupling a liquid chromatograph and chemical ionization mass spectrometer for offline analysis of organic aerosol
No full textA method is described for coupling a high-performance liquid chromatograph (HPLC) and chemical ionization mass spectrometer (CIMS) for the offline analysis of organic aerosol. It employs a nebulizer interface and the Vaporization Inlet for Aerosols (VIA), allowing for the transmission of analytes from the HPLC eluent into the CIMS inlet. Performance of the HPLC-VIA-CIMS system was assessed through the analysis of carboxylic acid standards, environmental chamber-generated secondary organic aerosol (SOA) formed from the ozonolysis of α-pinene, and ambient OA collected in an urban setting. Chromatographic peak shapes were retained through nebulization and evaporation, providing baseline-resolved separation of C6-C18 carboxylic acids and generating molecular-level detail that is not attainable using HPLC or CIMS alone. Instrument response was found to be linear (R2 > 0.97) over an order of magnitude (0.2-3.0 nmol or 2-30 nmol on column) for each of the 12 standards. Analysis of α-pinene ozonolysis SOA achieved isomer-resolved detection of both monomer and dimer reaction products and, through the use of a diode array detector (DAD), illustrated the preservation of chromatographic peak shape through nebulization and evaporation. The HPLC-VIA-CIMS instrument also shows potential for quantitative analysis, provided that authentic standards can be purchased or synthesized, and semi-quantitative analysis of UV-absorbing compounds such as nitrates and carboxylic acids by using a DAD. The system is compatible with small sample quantities (e.g., 30 μg of α-pinene ozonolysis SOA), allowing for detailed molecular characterization of field-collected SOA, including the identification of several monoterpene oxidation products. © 2025 Andre F. Schaum et al.TRUEforeig
Er3+-incorporated NaTi2(PO4)3 and its NIR to VIS photon upconversion properties
No full textLanthanide-doped materials, known for their unique nonlinear optical properties through upconversion (UC), exhibit considerable potential for various applications. However, new hosts are required to address the limitations of conventional UC materials by enhancing efficiency and stability, while facilitating innovative multifunctional applications. In this paper, we introduce Er3+-incorporated NaTi2(PO4)3 (E-NTPO), synthesized using the solid-state reaction method, and elucidate its UC photophysical properties. To our knowledge, this is the first report exploring NTPO as a UC host material. The E-NTPO exhibits bright green emission, with its emission characteristics significantly influenced by the dopant concentration. Increasing the Er3+ content notably affects both the emission intensity and the spectral distribution of UC. Based on dopant concentration and excitation power, a trend of varying red-to-green emission ratios is observed. Furthermore, the intriguing decay time of approximately 2 mu s suggests that complex cross-relaxation processes are involved in the UC emission. Our findings emphasize the crucial role of the oxide host in elucidating lanthanide UC physics and imply potential applications across various UC contexts.FALSEsciescopu
Quasi-1D Model for Bridging TCAD Simulation and Compact Modeling of Gate-All-Around MOSFETs
No full textA quasi-1D model is an intermediate-level approach that solves the one-dimensional carrier continuity equation along the channel direction, together with the cross-sectional charge model. It offers significantly higher computational efficiency compared to the technology computer-aided design (TCAD) simulation, while accurately accounting for geometric effects. By bridging the TCAD simulation and the compact modeling, the quasi-1D model enables a seamless transition between these two fields. In this work, we present results of our quasi-1D model for gate-all-around MOSFETs. Starting with the cross-sectional charge model, we demonstrate the complete quasi-1D model results and their implications. © 2025 Elsevier B.V., All rights reserved