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An approach named the defect-induced extension of photonic band gaps (PBGs) is proposed, in which a stratified periodic structure is combined with another stratified structure containing defect layers. For comparison, three structures composed of TiO2 and SiO2 alternating layers, perfect, five-defect and combined-photonic crystals (PCs), were fabricated by using an electron-beam evaporation system. The measured PBG width of combined-PCs extended to 370 nm at the normal incidence, nearly three times more than that of perfect ones, 130 nm, but a few ripples are observed within the PBG. In order to elucidate the origin of the ripples, the influence of the refractive-index contrast on the reflectance was analyzed theoretically. When the refractive-index contrast nH/nL≥1.7, the ripples are eliminated. More importantly, an overdoubled omnidirectional PBG is realized at nH/nL=2.56, covering the visible region completely. This approach is considered to be based on the light localization and a heterostructure resulting from introducing the impurity band and compensating for it using PCs with a strictly periodic structure, in which the thickness of every layer remains unchanged. These characteristics distinguish it from other methods proposed before, with the fabrication much easier. [ABSTRACT FROM AUTHOR]

Exosomes are extracellular vesicles with a diameter ranging from 40 to 160 nm. They are produced by hepatocytes, cholangiocytes, hepatic stellate cells (HSCs), liver sinusoidal endothelial cells (LSECs) and Kupffer cells in liver tissue. The secretion of exosomes might vary in quantity and composition in reaction to multiple triggers and various stages of disease. They transport various payloads, such as proteins, DNAs, and RNAs, and enable cell interaction to regulate myriad physiological and pathological processes in liver tissue. Long non-coding RNAs (lncRNAs) are a crucial component of exosomes with an excellent capability to regulate multiple cellular activities such as differentiation, development, metabolism, proliferation, apoptosis, and activation. With the advancements in transcriptomic and genomic study methods and database management technology, the functions and mechanisms of exosomal lncRNAs in liver diseases have been well-studied. This article delves into the detailed role of exosomal lncRNAs in liver disease onset and progression, ranging from hepatocellular carcinoma (HCC) to liver fibrosis drug-induced liver damage (DILI) and steatotic liver diseases., Competing Interests: Compliance with Ethical Standards. Conflict of Interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

A dimerlike-positional-correlation heterostructure is used in one-dimensional photonic crystals to introduce the defect mode with perfect transmittance. The switching behavior of the transmittance, at the defect mode, is demonstrated theoretically. When the normal incident beam is tilted at a negligibly small angle, the perfect transmittance peak vanishes. It is found that this condition causing this phenomenon can be easily met and controlled through elucidation on the mechanism. This finding is significant for potential applications in high-precision filters and optical switches. [ABSTRACT FROM AUTHOR]

Different phases of Ga 2 O 3 have been regarded as superior platforms for making new-generation high-performance electronic devices. However, understanding of thermal transport in different phases of nanoscale Ga 2 O 3 thin-films remains challenging, owing to the lack of phonon transport models and systematic experimental investigations. Here, thermal conductivity (TC) and thermal boundary conductance (TBC) of the ( 1 ¯ 010 ) $( {\bar 1010} )$ α-, ( 2 ¯ 01 ) $( {\bar 201} )\;$ β-, and (001) κ-Ga 2 O 3 thin films on sapphire are investigated. At ≈80 nm, the measured TC of α (8.8 W m -1 K -1 ) is ≈1.8 times and ≈3.0 times larger than that of β and κ, respectively, consistent with model based on density functional theory (DFT), whereas the model reveals a similar TC for the bulk α- and β-Ga 2 O 3 . The observed phase- and size-dependence of TC is discussed thoroughly with phonon transport properties such as phonon mean free path and group velocity. The measured TBC at Ga 2 O 3 /sapphire interface is analyzed with diffuse mismatch model using DFT-derived full phonon dispersion relation. Phonon spectral distribution of density of states, transmission coefficients, and group velocity are studied to understand the phase-dependence of TBC. This study provides insight into the fundamental phonon transport mechanism in Ga 2 O 3 thin films and paves the way for improved thermal management of high-power Ga 2 O 3 -based devices., (© 2023 Wiley‐VCH GmbH.)

The efficacy of petroleum spray oil against citrus psylla was tested in Guangzhou, China. As the oil concentration increased from 0.25% to 1.0% there was a linear decrease in the number of psylla of each stage present on foliar shoots after 8 days. When psylla infested shoots were sprayed with equivalent oil concentrations, survival was significantly different between oil treatments. Psylla survival was also stage-dependent, with 1st- 2nd instars being the most susceptible and eggs being the most tolerant to oil. Oil efficacy was compared to an organophosphate pesticide and an insect growth regulator, and all provided similarly effective controlofpsylla nymphs. Controlofeggs was not achieved by any of the treatments as application of sprays was not correctly timed. [ABSTRACT FROM AUTHOR]

This article describes the possible factors that can introduce discrepancies between measurements and three-dimensional EM simulations of millimeter-wave (mm-wave) antennas. The effects of the choice of the simulation solver, the relative permittivity and the homogeneity of the substrate material, the manufacturing tolerance, and the measurement errors are discussed. It is concluded that a fair comparison between measurements and simulations of mm-wave antennas can only be made if all these possible causes of discrepancies are taken into account. [ABSTRACT FROM AUTHOR]

[Fe]-hydrogenase harbors the iron-guanylylpyridinol (FeGP) cofactor, in which the Fe(II) complex contains acyl-carbon, pyridinol-nitrogen, cysteine-thiolate and two CO as ligands. Irradiation with UV-A/blue light decomposes the FeGP cofactor to a 6-carboxymethyl-4-guanylyl-2-pyridone (GP) and other components. Previous in vitro biosynthesis experiments indicated that the acyl- and CO-ligands in the FeGP cofactor can scramble, but whether scrambling occurred during biosynthesis or photolysis was unclear. Here, we demonstrate that the [ 18 O 1 -carboxy]-group of GP is incorporated into the FeGP cofactor by in vitro biosynthesis. MS/MS analysis of the 18 O-labeled FeGP cofactor revealed that the produced [ 18 O 1 ]-acyl group is not exchanged with a CO ligand of the cofactor, indicating that the acyl and CO ligands are scrambled during photolysis rather than biosynthesis, which ruled out any biosynthesis mechanisms allowing acyl/CO ligands scrambling. Time-resolved infrared spectroscopy indicated that an acyl-Fe(CO) 3 intermediate is formed during photolysis, in which scrambling of the CO and acyl ligands can occur. This finding also suggests that the light-excited FeGP cofactor has a higher affinity for external CO. These results contribute to our understanding of the biosynthesis and photosensitive properties of this unique H 2 -activating natural complex., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Glassy films of methyl-m-toluate have been vapor deposited onto a substrate equipped with interdigitated electrodes, facilitating in situ dielectric relaxation measurements during and after deposition. Samples of 200 nm thickness have been deposited at rates of 0.1 nm/s at a variety of deposition temperatures between 40 K and Tg = 170 K. With increasing depth below the surface, the dielectric loss changes gradually from a value reflecting a mobile surface layer to that of the kinetically stable glass. The thickness of this more mobile layer varies from below 1 to beyond 10 nm as the deposition temperature is increased, and its average fictive temperature is near Tg for all deposition temperatures. Judged by the dielectric loss, the liquid-like portion of the surface layer exceeds a thickness of 1 nm only for deposition temperatures above 0.8Tg, where near-equilibrium glassy states are obtained. After deposition, the dielectric loss of the material positioned about 5–30 nm below the surface decreases for thousands of seconds of annealing time, whereas the bulk of the film remains unchanged. [ABSTRACT FROM AUTHOR]

Glass-forming liquids exhibit long-lived, spatially correlated dynamical heterogeneity, in which some nm-scale regions in the fluid relax more slowly than others. In the nanoscale vicinity of an interface, glass-formers also exhibit the emergence of massive interfacial gradients in glass transition temperature Tg and relaxation time τ. Both of these forms of heterogeneity have a major impact on material properties. Nevertheless, their interplay has remained poorly understood. Here, we employ molecular dynamics simulations of polymer thin films in the isoconfigurational ensemble in order to probe how bulk dynamic heterogeneity alters and is altered by the large gradient in dynamics at the surface of a glass-forming liquid. Results indicate that the τ spectrum at the surface is broader than in the bulk despite being shifted to shorter times, and yet it is less spatially correlated. This is distinct from the bulk, where the τ distribution becomes broader and more spatially organized as the mean τ increases. We also find that surface gradients in slow dynamics extend further into the film than those in fast dynamics—a result with implications for how distinct properties are perturbed near an interface. None of these features track locally with changes in the heterogeneity of caging scale, emphasizing the local disconnect between these quantities near interfaces. These results are at odds with conceptions of the surface as reflecting simply a higher "rheological temperature" than the bulk, instead pointing to a complex interplay between bulk dynamic heterogeneity and spatially organized dynamical gradients at interfaces in glass-forming liquids. [ABSTRACT FROM AUTHOR]

Electrocatalytic reduction of CO2 (CO2ER) has been recognized as a promising utilization method of CO2. Catalysts are the core of the CO2ER and they have a great influence on the efficiency of CO2 catalytic conversion. Bimetallic catalysts are regarded as promising candidates as they combine the properties of bimetallic metals and show intermetallic synergy and structural designability. This review summarizes the latest research progress of bimetallic catalysts in CO2ER in recent years. The design strategies of bimetallic catalysts include improving the CO2 adsorption capacity, increasing active sites, tuning the binding energy of intermediates, tuning the hydrogen evolution reaction, etc. Bimetallic catalyst fabrication methods have also been summarized and analyzed. In the final part of the current work, the perspectives of design and fabrication of bimetallic catalysts have also been presented, to provide a basis for the future design and synthesis of bimetallic electrocatalysts with high activity, high selectivity, and high stability. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) electroreduction has extraordinary significance in curbing CO2 emissions while simultaneously producing value-added chemicals with economic and environmental benefits. In recent years, breakthroughs in designing catalysts, optimizing intrinsic activity, developing reactors, and elucidating reaction mechanisms have continuously driven the advancement of CO2 electroreduction. However, the industrialization of CO2 electroreduction remains a challenging task, with high energy consumption, high costs, limited reaction products, and restricted application scenarios being the issues that urgently need to be addressed. To accelerate the progress of CO2 electroreduction towards practical application, this review shifts the research focus from catalysts to aspects such as reactions and systems, aiming to improve reaction efficiency, reduce technical costs, expand the range of products, and enhance selectivity, offering readers a new perspective. In particular, innovative and specific design strategies such as CO2 reduction coupled with alternative oxidation, co-reduction reaction of CO2 and C/N/O/S-containing species, cascade systems, and integrated CO2 capture and reduction systems are discussed in detail. Additionally, personal views on the opportunities and future challenges of the aforementioned innovative strategies are provided, offering new insights for the future research and development of CO2 electroreduction. [ABSTRACT FROM AUTHOR]