4 research outputs found
Dimethyl acridine-based self-assembled monolayer as a hole transport layer for highly efficient inverted perovskite solar cells
Self-assembled monolayers (SAMs) have recently emerged as excellent hole transport materials in inverted perovskite solar cells (PSCs) owing to their ability to minimize parasitic absorption, regulate energy level alignment, and passivate perovskite defects. Herein, we design and synthesize a novel dimethyl acridine-based SAM, [2-(9,10-dihydro-9,9-dimethylacridine-10-yl)ethyl]phosphonic acid (2PADmA), and employ it as a hole-transporting layer in inverted PSCs. Experimental results show that the 2PADmA SAM can modulate perovskite crystallization, facilitate carrier transport, passivate perovskite defects, and reduce nonradiative recombination. Consequently, the 2PADmA-based device achieves an enhanced power conversion efficiency (PCE) of 24.01% and an improved fill factor (FF) of 83.92% compared to the commonly reported [2-(9H-carbazol-9-yl)ethyl] phosphonic acid (2PACz)-based control device with a PCE of 22.32% and FF of 78.42%, while both devices exhibit comparable open-circuit voltage and short-circuit current density. In addition, 2PADmA-based devices exhibit outstanding dark storage and thermal stabilities, retaining approximately ~98% and 87% of their initial PCEs after 1080 h of dark storage and 400 h of heating at 85 °C, respectively, both considerably superior to the control device
Characterization of a Thermostable and Surfactant-Tolerant Chondroitinase B from a Marine Bacterium <i>Microbulbifer</i> sp. ALW1
Chondroitinase plays an important role in structural and functional studies of chondroitin sulfate (CS). In this study, a new member of chondroitinase B of PL6 family, namely ChSase B6, was cloned from marine bacterium Microbulbifer sp. ALW1 and subjected to enzymatic and structural characterization. The recombinant ChSase B6 showed optimum activity at 40 °C and pH 8.0, with enzyme kinetic parameters of Km and Vmax against chondroitin sulfate B (CSB) to be 7.85 µg/mL and 1.21 U/mg, respectively. ChSase B6 demonstrated thermostability under 60 °C for 2 h with about 50% residual activity and good pH stability under 4.0–10.0 for 1 h with above 60% residual activity. In addition, ChSase B6 displayed excellent stability against the surfactants including Tween-20, Tween-80, Trion X-100, and CTAB. The degradation products of ChSase B6-treated CSB exhibited improved antioxidant ability as a hydroxyl radical scavenger. Structural analysis and site-directed mutagenesis suggested that the conserved residues Lys248 and Arg269 were important for the activity of ChSase B6. Characterization, structure, and molecular dynamics simulation of ChSase B6 provided a guide for further tailoring for its industrial application for chondroitin sulfate bioresource development
Deep learning-enhanced R-loop prediction provides mechanistic implications for repeat expansion diseases
Summary: R-loops play diverse functional roles, but controversial genomic localization of R-loops have emerged from experimental approaches, posing significant challenges for R-loop research. The development and application of an accurate computational tool for studying human R-loops remains an unmet need. Here, we introduce DeepER, a deep learning-enhanced R-loop prediction tool. DeepER showcases outstanding performance compared to existing tools, facilitating accurate genome-wide annotation of R-loops and a deeper understanding of the position- and context-dependent effects of nucleotide composition on R-loop formation. DeepER also unveils a strong association between certain tandem repeats and R-loop formation, opening a new avenue for understanding the mechanisms underlying some repeat expansion diseases. To facilitate broader utilization, we have developed a user-friendly web server as an integral component of R-loopBase. We anticipate that DeepER will find extensive applications in the field of R-loop research