Atomic Ordering Effect of Intermetallic PdCoNi/rGO Catalysts on Formic Acid Electro-oxidation

Pd-based alloys, especially for alloys containing early transition metals, have been extensively designed and applied to electro-oxidize formic acid for direct formic acid fuel cells owing to their capability to directly oxidize formic acid molecules via the dehydrogenation pathway. Adjusting the strain and electronic effects of Pd-based alloys is an effective method to regulate the adsorbing phenomena of intermediates on catalysts during formic acid oxidation and improve the catalytic activity and stability. The ordering degree of alloys plays an important role in modulating the adsorbing ability. In this work, we report a strategy varying the atomic ordering degree of PdCoNi/rGO trimetallic alloys to manipulate the strain and electronic effects and electrocatalytic performance toward formic acid oxidation. A series of PdCoNi/rGO-T trimetallic catalysts are synthesized, in which the atomic order of the trimetallic catalysts is regulated by annealing the wet-chemistry-synthesized PdCoNi/rGO alloy. As the annealing temperature increases, the atomic arrangement among Pd, Co, and Ni is ordered. Eventually, ordered intermetallic PdCoNi/rGO-T catalysts are generated. As the atomic ordering degree increases, the lattice constant decreases, and more charge transfers from Pd to Ni and Co, leading to enhanced strain and electronic effects. Moreover, the ordered intermetallic structure stabilizes Co and Ni atoms to prevent the dissolution of the transition metals in acidic electrolyte, and the strain and electronic effects in ordered PdCoNi/rGO catalysts are maintained. With an annealing temperature of 700 °C, the intermetallic PdCoNi/rGO-700 exhibits the highest specific activity of 8.33 mA/cm2, which is 1.95-fold improved compared to pristine PdCoNi/rGO alloy (3.23 mA/cm2) and 2.48 times compared to Pd/rGO-700 (2.54 mA/cm2). Moreover, PdCoNi/rGO-700 also shows outstanding catalytic durability due to its excellent structural stability. We believe that this research helps in developing Pd-based alloy catalysts with high activity and stability for formic acid electro-oxidation

Quantum Dot-based Luminescent Solar Concentrators Fabricated through the Ultrasonic Spray-Coating Method

Luminescent solar concentrators (LSCs) are a class of wave-guiding devices that can harvest solar light and concentrate it to targeted smaller areas. When coupled with photovoltaic devices (PVs), LSCs hold the potential to be integrated into various application setups, especially for building facade integration toward net-zero-energy buildings. Developing reliable LSC fabrication methods with easy scalability, high adaptability, and device controllability has been an important research topic. In this work, we report an ultrasonic nebulization-assisted spray deposition technique to fabricate quantum dot (QD)-based LSCs (QD-LSCs). This method allows for the production of high-performance QD-LSCs with different device dimensions and geometries. In addition, the quality of the QD thin-film coating layer is relatively independent of the concentration and volume of the coating QD ink solution, allowing for deliberate programming and performance optimization of the resulting QD-LSC devices. We anticipate that this ultrasonic spray coating method can be widely applied to the manufacturing of high-quality LSC devices that are integrable to various applications

Lanthanide Doping into All-Inorganic Heterometallic Halide Layered Double Perovskite Nanocrystals for Multimodal Visible and Near-Infrared Emission

The introduction of lanthanide ions (Ln3+) into all-inorganic lead-free halide perovskites has captured significant attention in optoelectronic applications. However, doping Ln3+ ions into heterometallic halide layered double perovskite (LDP) nanocrystals (NCs) and their associated doping mechanisms remain unexplored. Herein, we report the first colloidal synthesis of Ln3+ (Yb3+, Er3+)-doped LDP NCs utilizing a modified hot-injection method. The resulting NCs exhibit efficient near-infrared (NIR) photoluminescence in both NIR-I and NIR-II regions, achieved through energy transfer down-conversion mechanisms. Density functional theory calculations reveal that Ln3+ dopants preferentially occupy the Sb3+ cation positions, resulting in a disruption of local site symmetry of the LDP lattices. By leveraging sensitizations of intermediate energy levels, we delved into a series of Ln3+-doped Cs4M(II)Sb2Cl12 (M(II): Cd2+ or Mn2+) LDP NCs via co-doping strategies. Remarkably, we observe a brightening effect of the predark states of Er3+ dopant in the Er3+-doped Cs4M(II)Sb2Cl12 LDP NCs owing to the Mn component acting as an intermediate energy bridge. This study not only advances our understanding of energy transfer mechanisms in doped NCs but also propels all-inorganic LDP NCs for a wider range of optoelectronic applications

Reconfigurable Photonic Crystals Enabled by Multistimuli-Responsive Shape Memory Polymers Possessing Room Temperature Shape Processability

Traditional shape memory polymers (SMPs) are mostly thermoresponsive, and their applications in nano-optics are hindered by heat-demanding programming and recovery processes. By integrating a polyurethane-based shape memory copolymer with templating nanofabrication, reconfigurable/rewritable macroporous photonic crystals have been demonstrated. This SMP coupled with the unique macroporous structure enables unusual all-room-temperature shape memory cycles. “Cold” programming involving microscopic order–disorder transitions of the templated macropores is achieved by mechanically deforming the macroporous SMP membranes. The rapid recovery of the permanent, highly ordered photonic crystal structure from the temporary, disordered configuration can be triggered by multiple stimuli including a large variety of vapors and solvents, heat, and microwave radiation. Importantly, the striking chromogenic effects associated with these athermal and thermal processes render a sensitive and noninvasive optical methodology for quantitatively characterizing the intriguing nanoscopic shape memory effects. Some critical parameters/mechanisms that could significantly affect the final performance of SMP-based reconfigurable photonic crystals including strain recovery ratio, dynamics and reversibility of shape recovery, as well as capillary condensation of vapors in macropores, which play a crucial role in vapor-triggered recovery, can be evaluated using this new optical technology

Renal Transplant Recipients Treated with Calcineurin-Inhibitors Lack Circulating Immature Transitional CD19⁺CD24^hiCD38^hi Regulatory B-Lymphocytes - Fig 4

<p>The amount of peripheral circulating CD19⁺CD24^hiCD38^hi cells correlated with the clinical outcome after kidney transplantation A low amount of peripheral circulating CD19⁺CD24^hiCD38^hi cells was associated with a lower eGFR <b>(A).</b> The orange-framed box in <b>B</b> indicates a subgroup of 29 patients that exhibited <1% of CD24^hi38^hi expressing CD19⁺ peripherally circulating B-cells. 31% (n = 9) of these patients experienced a biopsy proven rejection event 24 months before or after the analyses (5 patients before and 4 patients within 24 months after sample assessment).</p

The calcineurin inhibitors tacrolimus and CsA inhibit IL-10 expression of B-cells <i>in vitro</i> and <i>in vivo</i>.

<p>Freshly isolated PBMCs from healthy subjects (n = 9) and renal transplant recipients (n = 9) were mitogen/toll-like-receptor 9 stimulated for 72 hours and subsequently stained for surface CD19 and intracellular IL-10 or with the respective isotype control antibodies <b>(A).</b> The representative dot plots on the upper left in <b>A</b> show the intracellular IL-10 expression of stimulated CD19⁺ B-cells from a healthy subject and representative renal transplant recipients receiving either tacrolimus or CsA (after gating on CD19⁺ B-cells). The scatter plot in <b>B</b> summarizes the results of multiple unrelated experiments. PBMCs of healthy subjects were stimulated like described before in presence or absence of different concentrations of tacrolimus (n = 4) <b>(C)</b> or CsA (n = 4) <b>(D)</b>, as indicated. The bar graphs in <b>E</b> depict the decline of IL-10 production (in %) of PBMCs vs. positively isolated CD19⁺ B-cells after stimulation co-cultured with CsA (n = 9 healthy subjects). 7-AAD staining was performed to ensure viability of cell culture.</p

Calcineurin inhibitors reduce the expression of CD24 and CD38 on CD19⁺ B lymphocytes.

<p>The expression of CD24, CD38 and IL-10 after gating on CD19⁺ B-cells is shown in a representative healthy subject, indicating that only a minority of IL-10 producing B-cells highly express CD38 <b>(A)</b>. The dot blots in <b>B</b> depict CD24^hiCD38^hi B-cells (red-framed boxes) in a representative healthy subject, a renal transplant recipient receiving a CsA or tacrolimus based immunosuppression. The respective isotype control staining is depicted in between. The scatter plot graphs in <b>C</b> and <b>D</b> summarize the results and show that treatment with tacrolimus (n = 35) or CsA (n = 11) not only reduce the percentage of peripherally circulating B-lymphocytes <b>(C)</b> but also affect the CD24^hiCD38^hi B-cell subset <b>(D)</b>. In contrast to healthy subjects (n = 16), the CD24^hi38^hi expressing B-cell subset of renal transplant patients receiving a calcineurin inhibitor were significantly reduced or even blunted <b>(B, D)</b>. No correlation was found between the amount of CD24^hiCD38^hi B-cells and time of sample assessment after transplantation <b>(E</b>, Spearman test, <i>r</i> = -0,01, <i>p</i> = 0,9450).</p

Image_1_Relationship between gut microbiota and lymphocyte subsets in Chinese Han patients with spinal cord injury.TIF

This study is to investigate the changes of lymphocyte subsets and the gut microbiota in Chinese Han patients with spinal cord injury (SCI). We enrolled 23 patients with SCI and 21 healthy controls. Blood and fecal samples were collected. The proportion of lymphocyte subsets was detected by flow cytometry. 16S rDNA sequencing of the V4 region was used to analyze the gut microbiota. The changes of the gut microbiota were analyzed by bioinformatics. Correlation analysis between gut microbiota and lymphocyte subsets was performed. CD4 + cells, CD4 + /CD8 + ratio and CD4 + CD8 + cells in peripheral blood of SCI patients were significantly lower than those of the control group (P < 0.05). There was no significant difference in B cells and CIK cells between the SCI group and the control group. The gut microbiota community diversity index of SCI patients was significantly higher than that of healthy controls. In SCI patients, the relative abundance of Lachnospiraceae (related to lymphocyte subset regulation), Ruminococcaceae (closely related to central nervous system diseases), and Escherichia-Shigella (closely related to intestinal infections) increased significantly, while the butyrate producing bacteria (Fusobacterium) that were beneficial to the gut were dramatically decreased. Correlation analysis showed that the five bacterial genera of SCI patients, including Lachnospiraceae UCG-008, Lachnoclostridium 12, Tyzzerella 3, Eubacterium eligens group, and Rumencocciucg-002, were correlated with T lymphocyte subsets and NK cells. In the SCI group, the flora Prevotella 9, Lachnospiraceae NC2004 group, Veillonella, and Sutterella were positively correlated with B cells. However, Fusobacterium and Akkermansia were negatively correlated with B cells. Moreover, Roseburia and Ruminococcaceae UCG-003 were positively correlated with CIK cells. Our results suggest that the gut microbiota of patients with SCI is associated with lymphocyte subsets. Therefore, it is possible to improve immune dysregulation in SCI patients by modulating gut microbiota, which may serve as a new therapeutic method for SCI.</p