Enhancing Hot Carrier Photoelectric Efficiency through the Boosted Collection of Hot Holes via Au/ZrO2/Si Tunneling Junctions.

Metallic nanoparticles can generate photoexcited hot carriers on the femtosecond scale under light excitation, which holds immense significance for applications such as optical communication and ultrafast imaging. In this study, a tunnelling junction structure with ZrO2 as the dielectric layer is designed and fabricated to achieve efficient hot hole collection between Au nanoparticles and P-type Si. Through characterizations of photoconductive atomic force microscopy, the electrical transition from an ohmic contact to a tunneling junction is confirmed, and the transfer pathway of Au hot holes to P-type Si upon 520 nm excitation is clearly observed. The impact of the tunneling structure on device performance is investigated through the fabrication of Si/ZrO2/Au/TiO2 photodiodes. The performance tests show that hot hole collection by the tunneling effect significantly enhances a range of parameters, e.g., external quantum efficiency by 250%. Noticeably, the external quantum efficiency attributed to photogenerated hot carriers under 520 nm excitation is estimated to exceed 2.5%. Moreover, the transient photoresponse of the photodiodes is examined with a typical rising time of less than 20 ns.

Ubiquitin-independent degradation of Bim blocks macrophage pyroptosis in sepsis-related tissue injury.

Pyroptosis, a typical inflammatory cell death mode, has been increasingly demonstrated to have therapeutic value in inflammatory diseases such as sepsis. However, the mechanisms and therapeutic targets of sepsis remain elusive. Here, we reported that REGγ inhibition promoted pyroptosis by regulating members of the gasdermin family in macrophages. Mechanistically, REGγ directly degraded Bim, a factor of the Bcl-2 family that can inhibit the cleavage of GSDMD/E, ultimately preventing the occurrence of pyroptosis. Furthermore, cecal ligation and puncture (CLP)-induced sepsis model mice showed downregulation of REGγ at both the RNA and protein levels. Gasdermin-mediated pyroptosis was augmented in REGγ-knockout mice, and these mice exhibited more severe sepsis-related tissue injury. More importantly, we found that REGγ expression was downregulated in clinical sepsis samples, such as those from patients with Pseudomonas aeruginosa (PA) infection. Finally, PA-infected mice showed decreased REGγ levels in the lung. In summary, our study reveals that the REGγ-Bim-GSDMD/E pathway is a novel regulatory mechanism of pyroptosis in sepsis-related tissue injury.

Interplay between Bile Acids and Intestinal Microbiota: Regulatory Mechanisms and Therapeutic Potential for Infections.

Bile acids (BAs) play a crucial role in the human body's defense against infections caused by bacteria, fungi, and viruses. BAs counteract infections not only through interactions with intestinal bacteria exhibiting bile salt hydrolase (BSH) activity but they also directly combat infections. Building upon our research group's previous discoveries highlighting the role of BAs in combating infections, we have initiated an in-depth investigation into the interactions between BAs and intestinal microbiota. Leveraging the existing literature, we offer a comprehensive analysis of the relationships between BAs and 16 key microbiota. This investigation encompasses bacteria (e.g., Clostridioides difficile (C. difficile), Staphylococcus aureus (S. aureus), Escherichia coli, Enterococcus, Pseudomonas aeruginosa, Mycobacterium tuberculosis (M. tuberculosis), Bacteroides, Clostridium scindens (C. scindens), Streptococcus thermophilus, Clostridium butyricum (C. butyricum), and lactic acid bacteria), fungi (e.g., Candida albicans (C. albicans) and Saccharomyces boulardii), and viruses (e.g., coronavirus SARS-CoV-2, influenza virus, and norovirus). Our research found that Bacteroides, C. scindens, Streptococcus thermophilus, Saccharomyces boulardii, C. butyricum, and lactic acid bacteria can regulate the metabolism and function of BSHs and 7α-dehydroxylase. BSHs and 7α-dehydroxylase play crucial roles in the conversion of primary bile acid (PBA) to secondary bile acid (SBA). It is important to note that PBAs generally promote infections, while SBAs often exhibit distinct anti-infection roles. In the antimicrobial action of BAs, SBAs demonstrate antagonistic properties against a wide range of microbiota, with the exception of norovirus. Given the intricate interplay between BAs and intestinal microbiota, and their regulatory effects on infections, we assert that BAs hold significant potential as a novel approach for preventing and treating microbial infections.

Heterostructure Fe7S8/Mn(OH)2 of incomplete sulfurization induces Mn atoms with high density of states for enhancing oxygen evolution reaction and supercapacitor electrochemical performance.

Heterostructures and the introduction of heterogeneous elements have been regarded as effective strategies to promote electrochemical performance. Herein, sulfur species are introduced by a simple hydrothermal vulcanization method, which constructs the open heterostructure Fe7S8/Mn(OH)2 as a bifunctional material. The open cordyceps-like morphology can make the material contact more sufficiently with the electrolyte, exposing a large number of reaction sites. Furthermore, the introduction of the heterogeneous element S successfully constructs a heterogeneous interface, the interface-modulated composite material consists of Mn atoms contributing the main density of states (DOS) near the Fermi energy level from the density functional theory (DFT) calculations, which optimizes the adsorption energy of oxygen-containing intermediates during the oxygen evolution reaction (OER) process and reduces the reaction energy barrier, being conducive to the improvement of the material's electrochemical properties. As predicted, the Fe7S8/Mn(OH)2 material exhibits remarkable electrochemical properties, such as an overpotential of 202 mV at 10 mA cm-2 for the oxygen evolution reaction and even a specific capacitance of 2198 F g-1 at 1 A g-1. This work provides new insights into the role of introducing sulfur species and controlling the structure of the material, and exemplifies novel design ideas for developing bifunctional materials for energy storage and conversion.

L-valine derived from the gut microbiota protects sepsis-induced intestinal injury and negatively correlates with the severity of sepsis.

Background: The protective role of gut microbiota and its metabolites against intestinal damage in sepsis patients remain unclear. Methods: Fecal samples were acquired from patients categorized into sepsis and non-sepsis groups for analysis of microbial composition via 16S rRNA sequencing and untargeted metabolomics analysis. We assessed the impact of gut microbiota from sepsis patients on intestinal barriers in antibiotic-treated mice. Furthermore, We conducted spearman's correlation analysis to examine the relationship between metabolites and the severity of sepsis. Additionally, we performed animal experiments to validate the functionality of identified metabolites. Results: The diversity of intestinal flora is decreased in patients with sepsis compared to the control group. Through fecal microbiota transplantation experiments, it was discovered that the gut microbiota derived from sepsis patients could induce intestinal damage in antibiotic-treated mice. Metabolomics analysis of the microbiota revealed a significant enrichment of the Valine, leucine, and isoleucine biosynthesis pathway. Further analysis showed a significant decrease in the abundance of L-valine in sepsis patients, which was negatively correlated with APACHE-II and SOFA scores. In sepsis mouse experiments, it was found that L-valine could alleviate sepsis-induced intestinal damage. Conclusion: Alterations in microbial and metabolic features in the gut can affect the severity of sepsis. Furthermore, L-valine can protect against sepsis-induced intestinal injury.

Excellent Electroluminescent Property of Eu3+-Induced Polystyrene-co-poly(acrylic acid) Aggregates (EIPAs) in Polymeric Light-Emitting Diodes.

Eu3+-induced polystyrene-co-poly(acrylic acid) aggregates (EIPAs) were synthesized using a self-assembly approach, and their structures and photophysical characteristics were examined to achieve effective monochromatic red emission in polymer light-emitting diodes (PLEDs). By adjusting the monomer ratio in RAFT polymerization, the size of Eu3+-induced block copolymer nanoaggregates can be regulated, thereby modulating the luminescence intensity. High-performance bilayer polymer light-emitting devices were fabricated using poly(9,9-dioctylfluorene) (PFO) and 2-(tert-butylphenyl)-5-biphenylyl-1,3,4-oxadiazole (PBD) as the host matrix, with EIPAs as the guest dopant. The devices exhibited narrow red emission at 615 nm with a full width at half-maximum (fwhm) of 15 nm across doping concentrations of 1, 3, 5, and 10 wt %. At a doping concentration of 3 wt %, the device achieved a maximum brightness of 1864.48 cd/m2 at 193.82 mA/cm2 and an external quantum efficiency of 3.20% at a current density of 3.5 mA/cm2. These results indicate that incorporating polystyrene-co-poly(acrylic acid) with Eu3+ complexes enhances the excitation and emission intensity, as well as the structural stability of the emitting layer in PLEDs, thereby improving the device performance.

A Uni-Micelle Approach for the Controlled Synthesis of Monodisperse Gold Nanocrystals.

Small-size gold nanoparticles (AuNPs) are showing large potential in various fields, such as photothermal conversion, sensing, and medicine. However, current synthesis methods generally yield lower, resulting in a high cost. Here, we report a novel uni-micelle method for the controlled synthesis of monodisperse gold nanocrystals, in which there is only one kind micelle containing aqueous solution of reductant while the dual soluble Au (III) precursor is dissolved in oil phase. Our synthesis includes the reversible phase transfer of Au (III) and "uni-micelle" synthesis, employing a Au (III)-OA complex as an oil-soluble precursor. Size-controlled monodisperse AuNPs with a size of 4-11 nm are synthesized by tuning the size of the micelles, in which oleylamine (OA) is adsorbed on the shell of micelles and enhances the rigidity of the micelles, depressing micellar coalescence. Monodisperse AuNPs can be obtained through a one-time separation process with a higher yield of 61%. This method also offers a promising way for the controlled synthesis of small-size alloy nanoparticles and semiconductor heterojunction quantum dots.

Controlling the graphite-like microcrystalline structure of lignin-based ultrafine carbon fibers via the design of condensed structures.

Obtaining lignin-based graphite-like microcrystallites at a relatively low carbonization temperature is still very challenging. In this work, we report a new method based on condensed structures, for regulating graphite-like microcrystalline structures via the incorporation of 4,4'-diphenylmethane diisocyanate (MDI) into the main structure of lignin. The effects of MDI on the thermal properties of lignin and the graphite-like microcrystalline structure of lignin-based ultrafine carbon fibers were extensively studied and investigated. The incorporation of MDI decreased the thermal stability of lignin, increased the carbon yield and enhanced the formation of graphite-like microcrystallites, which are beneficial for reducing energy consumption during the preparation of lignin-based carbon fibers. The modified lignin-based ultrafine carbon fibers (M-LCFs) demonstrated satisfactory electrochemical performance, including high specific capacitance, low charge transfer resistance, and good cycle performance. The M-LCFs-3/2 electrode had a specific capacitance of 241.3 F g-1 at a current density of 0.5 A g-1, and a residual ratio of 90.2 % after 2000 charge and discharge cycles. This study provides a new approach to control the graphite-like microcrystalline structure and electrochemical performance while also optimizing the temperature.

Tryptophan metabolites relieve intestinal Candida albicans infection by altering the gut microbiota to reduce IL-22 release from group 3 innate lymphoid cells of the colon lamina propria.

Invasive candidiasis may be caused by Candida albicans (C. albicans) colonization of the intestinal tract. Preventing intestinal damage caused by Candida albicans infection and protecting intestinal barrier function have become a critical issue. Integrated analyses of the microbiome with metabolome revealed a remarkable shift of the gut microbiota and tryptophan metabolites, kynurenic acid (KynA), and indolacrylic acid (IA) in mice infected with C. albicans. The transcriptome sequencing indicated that differentially expressed genes were significantly associated with innate immune responses and inflammatory responses. The results of this study suggest that KynA and IA (KI) can alleviate intestinal damage caused by Candida albicans infection in mice by reducing intestinal permeability, increasing intestinal firmness, alleviating intestinal inflammation, and reducing the secretion of interleukin-22 (IL-22) in the 3 groups of colon innate lymphoid cells (ILC3). We performed a fecal microbiota transplantation (FMT) experiment and found that the intestinal barrier function, inflammation, and IL-22 secretion of ILC3 in the colon lamina propria of the recipient mice subjected to C. albicans infection and KI treatment were consistent with the trends of the donor mice. Our results suggest that tryptophan metabolites may directly regulate colon lamina ILC3 to promote intestinal resistance to C. albicans invasion, or indirectly regulate the ILC3 secretion of IL-22 to play a protective role in the intestinal barrier by affecting intestinal microorganisms, which may become a potential target for alleviating intestine borne C. albicans infection.