Two-dimensional (n = 1) ferroelectric film solar cells.

Molecular ferroelectrics that have excellent ferroelectric properties, a low processing temperature, narrow bandgap, and which are lightweight, have shown great potential in the photovoltaic field. However, two-dimensional (2D) perovskite solar cells with high tunability, excellent photo-physical properties and superior long-term stability are limited by poor out-of-plane conductivity from intrinsic multi-quantum-well electronic structures. This work uses 2D molecular ferroelectric film as the absorbing layer to break the limit of multiple quantum wells. Our 2D ferroelectric solar cells achieve the highest open-circuit voltage (1.29 V) and the best efficiency (3.71%) among the 2D (n = 1) Ruddlesden-Popper perovskite solar cells due to the enhanced out-of-plane charge transport induced by molecular ferroelectrics with a strong saturation polarization, high Curie temperature and multiaxial characteristics. This work aims to break the inefficient out-of-plane charge transport caused by the limit of the multi-quantum-well electronic structure and improve the efficiency of 2D ferroelectric solar cells.

Enhanced M2 Polarization of Oriented Macrophages on the P(VDF-TrFE) Film by Coupling with Electrical Stimulation.

Electrical stimulation (ES) has been considered a promising strategy in regulating intracellular communication, membrane depolarization, ion transport, etc. Meanwhile, cell topography, such as the alignment and elongation in anisotropic orientation, also plays a critical role in triggering mechanotransduction as well as the cellular fate. However, coupling of ES and cell orientation to regulate the polarization of macrophages is yet to be explored. In this work, we intended to explore the polarization of macrophages on a poly(vinylidene fluoride-trifluoroethylene [P(VDF-TrFE)] film with intrinsic microstripe roughness, which was covered on indium tin oxide planar microelectrodes. We found that mouse bone marrow-derived macrophages (BMDMs) cultured on a P(VDF-TrFE) film exhibited an elongated morphology aligned with the microstripe crystal whisker, but their polarization behavior was not affected. However, the elongated cells were susceptible to ES and upregulated their M2 polarization, as verified by the related expression of phenotype markers, cytokines, and genes, while not affecting M1 polarization. This is due to the increased expression of the M2 polarization receptor interleukin-4Rα on the surface of elongated BMDMs, while the M1 polarization receptor toll-like receptor 4 was not affected. Thus, M2 polarization was singularly enhanced after activation of polarization by ES. The combination of surface morphology and ES to promote M2 single polarization in this work provides a new perspective for regulating macrophage polarization in the field of immunotherapy.

Copper-Catalyzed Intermolecular Cross-dehydrogenative C-N Coupling at Room Temperature via Remote Activating Group Enabled Radical Relay Strategy.

Employing N-fluorobenzenesulfonimide (NFSI) as a nitrogen-centered radical (NCR) precursor, an intermolecular C(sp2)-N coupling on heteroarenes or substituted benzenes with remote activated aniline derivatives via copper catalyzed N-N radical relay strategy at room temperature is developed. Good to excellent yields are acquired, and no ligand or additive is required. Reaction scope investigation and preliminary mechanistic studies demonstrate that the remote activating strategy and delicate control on the reactivities of active NCR species are essential to guarantee satisfactory chemo- and site-selectivity.

Ammonium benzenesulfonate as an electrolyte additive to relieve the irreversible accumulation of lithium sulfide for high-energy density lithium-sulfur battery.

Based on the dissolution and conversion mechanism of lithium-sulfur (Li-S) batteries, insulating solid short-chain polysulfides (Li2S2/Li2S) will continuously passivate and corrode the active interface of cathode and anode, which seriously affects its performance. Herein, ammonium benzenesulfonate (NH4BS) is proposed as a soluble ammonium salt to dissolve Li2S in the ether electrolyte, according to the inductive effect of NH4+ cation and O atom on Li-S bond. This is beneficial to alleviate the interface problem of electrodes and irreversible loss of active materials. Noticeably, soluble Li2S regulates its deposition behavior from 2D to 3D, which is conducive to the more effective use of conductive surface. Moreover, the addition of NH4BS can increase the dissociation degree of long-chain polysulfides, so that the diffusion rate and reaction kinetics of active substances are improved. Profiting from these functions, the Li-S cells with NH4BS act out excellent cyclic stability in the long cycle of 0.5 C and 2 C. Under the extreme conditions of high sulfur loading and low electrolyte-sulfur ratio, the cells with NH4BS can cycle stably for 196 cycles, which significantly prolongs the battery life. The proposal of NH4BS broadens a new idea to solve the interface problem of Li-S cells and stimulate the research enthusiasm of developing soluble ammonium salt.

Photo-thermic mineralized collagen coatings and their modulation of macrophages polarization.

Macrophages polarization in bone immune microenvironment is crucial in bone regeneration. In this work, mineralized collagen (MC) coatings with photo-thermal effect were prepared through incorporation of polydopamine (PDA). MC coatings with different thicknesses were deposited on titanium substrate through electrochemical deposition. PDA preformed on the substrate, acting as a photo-thermal agent. The effects of light illumination, i.e., different thermal effects, on the polarization of mouse bone marrow-derived macrophages were explored. It was found that heat can promote the M1 polarization of macrophages and inhibit the M2 polarization. Also, gene expression results revealed that such photo illumination based macrophage modulation is effective and safe. It provides a possible way for the design of functional materials to regulate the bone immune microenvironment.

Efficient molecular ferroelectric photovoltaic device with high photocurrent via lewis acid-base adduct approach.

Traditional inorganic oxide ferroelectric materials usually have band gaps above 3 eV, leading to more than 80% of the solar spectrum unavailable, greatly limiting the current density of their devices just atµA cm-2level. Therefore, exploring ferroelectric materials with lower band gaps is considered as an effective method to improve the performance of ferroelectric photovoltaic devices. Inorganic ferroelectric materials are often doped with transition metal elements to reduce the band gap, which is a complex doping and high temperature fabrication process. Recently, molecular ferroelectric materials can change the symmetry and specific interactions of crystals at the molecular level by chemically modifying or tailoring cations with high symmetry, enabling rational design and banding of ferroelectricity in the framework of perovskite simultaneously. Therefore, the molecular ferroelectric materials have a great performance for both excellent ferroelectricity and narrow band gap without doping. Here, we report a ferroelectric photovoltaic device employing an organic-inorganic hybrid molecular ferroelectric material with a band gap of 2.3 eV to obtain high current density. While the poor film quality of molecular ferroelectrics still limits it. The Lewis acid-base adduct is found to greatly improve the film quality with lower defect density and higher carrier mobility. Under standard AM 1.5 G illumination, the photocurrents of ∼1.51 mA cm-2is achieved along with a device efficiency of 0.45%. This work demonstrates new possibilities for the application of molecular ferroelectric films with narrow band gaps in photovoltaic devices, and lays a foundation for Lewis acid-base chemistry to improve the quality of molecular ferroelectric thin films to obtain high current densities and device performance.

The complete chloroplast genome sequence of Corylopsis sinensis (Hamamelidaceae).

Corylopsis sinensis Hemsl. is a deciduous shrub endemic to China, which is a valuable medicinal and ornamental species. In this study, we report the complete chloroplast genome sequence of C. sinensis, providing a genomic basis for future research. The chloroplast genome is 159,419 base pairs (bp) in length, with a large single-copy (LSC) region of 88,152 bp, a small single-copy (SSC) region of of 18,701 bp, and two inverted repeat (IR) regions of 26,283 bp. The overall GC content is 38.0% and the chloroplast genome encodes 113 unique genes including 79 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. The phylogenetic results show that C. sinensis is sister to C. spicata. These results of C. sinensis will improve our understanding of the evolution of Corylopsis and Hamamelidaceae.

Effects of electrical stimulation on cytokine-induced macrophage polarization.

Macrophages have two functionalized phenotypes, M1 and M2, and the regulation of M1/M2 polarization of macrophages is critical for tissue repair. Tissue-derived immune factors are considered the major drivers of macrophage polarization. Based on the main cytokine-induced polarization pathways, we tested the effect of electrical stimulation (ES) of macrophages on the regulation of M1/M2 polarization and a possible synergistic effect with the cytokines. Indium tin oxide (ITO) planar microelectrodes were used to produce ES under different voltages, frequencies and waveforms. We evaluated the influence of ES on the cytokine-induced M1/M2 polarization using mouse bone marrow-derived macrophages cultured with both lipopolysaccharide (LPS)/IFN-γ factors and IL-4 factors for M1 and M2, respectively. The results showed that ES promoted the cytokine-induced macrophage polarization. Importantly, we found that stimulation with a square waveform selectively promoted LPS/IFN-γ-induced M1 polarization, while stimulation with a sinusoidal waveform promoted both LPS/IFN-γ-induced M1, and IL-4-induced M2 polarization. Mechanistically, stimulation with a square waveform affected the intracellular ion concentration, whereas stimulation with a sinusoidal waveform promoted both the intracellular ion concentration and membrane receptors. We hereby establish an ES-mediated strategy for immunomodulation via macrophage polarization.

Draft Genome Sequence of Schnuerera sp. Strain xch1, Isolated from the Tibetan Plateau.

In this study, we report the draft genome sequence of Schnuerera sp. strain xch1, which was isolated from a high-altitude thermal spring on the Tibetan Plateau. The enzymes and metabolic pathways of the strain may have further applications in biomass technology.

Unexpectedly high mutation rate of a deep-sea hyperthermophilic anaerobic archaeon.

Deep-sea hydrothermal vents resemble the early Earth, and thus the dominant Thermococcaceae inhabitants, which occupy an evolutionarily basal position of the archaeal tree and take an obligate anaerobic hyperthermophilic free-living lifestyle, are likely excellent models to study the evolution of early life. Here, we determined that unbiased mutation rate of a representative species, Thermococcus eurythermalis, exceeded that of all known free-living prokaryotes by 1-2 orders of magnitude, and thus rejected the long-standing hypothesis that low mutation rates were selectively favored in hyperthermophiles. We further sequenced multiple and diverse isolates of this species and calculated that T. eurythermalis has a lower effective population size than other free-living prokaryotes by 1-2 orders of magnitude. These data collectively indicate that the high mutation rate of this species is not selectively favored but instead driven by random genetic drift. The availability of these unusual data also helps explore mechanisms underlying microbial genome size evolution. We showed that genome size is negatively correlated with mutation rate and positively correlated with effective population size across 30 bacterial and archaeal lineages, suggesting that increased mutation rate and random genetic drift are likely two important mechanisms driving microbial genome reduction. Future determinations of the unbiased mutation rate of more representative lineages with highly reduced genomes such as Prochlorococcus and Pelagibacterales that dominate marine microbial communities are essential to test these hypotheses.