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Despite the recent availability of vaccines against the acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the search for inhibitory therapeutic agents has assumed importance especially in the context of emerging new viral variants. In this paper, we describe the discovery of a novel noncovalent small-molecule inhibitor, MCULE-5948770040, that binds to and inhibits the SARS-Cov-2 main protease (Mpro) by employing a scalable high-throughput virtual screening (HTVS) framework and a targeted compound library of over 6.5 million molecules that could be readily ordered and purchased. Our HTVS framework leverages the U.S. supercomputing infrastructure achieving nearly 91% resource utilization and nearly 126 million docking calculations per hour. Downstream biochemical assays validate this Mpro inhibitor with an inhibition constant (Ki) of 2.9 μM (95% CI 2.2, 4.0). Furthermore, using room-temperature X-ray crystallography, we show that MCULE-5948770040 binds to a cleft in the primary binding site of Mpro forming stable hydrogen bond and hydrophobic interactions. We then used multiple μs-time scale molecular dynamics (MD) simulations and machine learning (ML) techniques to elucidate how the bound ligand alters the conformational states accessed by Mpro, involving motions both proximal and distal to the binding site. Together, our results demonstrate how MCULE-5948770040 inhibits Mpro and offers a springboard for further therapeutic design.

In this work, we report a facile dealloying strategy to tailor the surface state of nanoporous TiO2 towards high-efficiency sulfur host material for lithium-sulfur (Li-S) batteries. When used as a sulfur cathode material, the oxygen-deficient TiO2-x exhibits enhanced lithium polysulfides (LiPS) adsorption and conversion kinetics that effectively tackle the shuttle effect in lithium-sulfur batteries. The excellent ability of the oxygen vacancy sites on TiO2-x surface to trap LiPS is proved by experimental observations and density functional theory (DFT) calculations. Meanwhile, it also promotes conversion kinetics of lithium polysulfides, as verified by the asymmetric cell experiment. Accordingly, compared with the S/TiO2 cathode, the oxygen-deficient S/TiO2-x electrode exhibits preeminent rate and cycling performance in lithium-sulfur batteries: it delivers an ultra-low capacity decay of 0.039 % per cycle after 1000 cycles at 1 C. Tunning the surface state of metal oxides by dealloying method offers a new facile strategy to design efficient sulfur cathode materials for lithium-sulfur batteries.

Vinyl acetate is an organic chemical raw material of great industrial value. It is widely used in synthetic film, adhesive, coating and textile slurry. The production route of vinyl acetate is introduced, and the advantages and disadvantages of synthesis methods of vinyl acetate method, acetylene method, EDA cracking method, base synthesis method and Halcon method are compared. The method of carbide acetylene has high economic efficiency, low energy consumption and good environmental protection, proposing the development direction of ethylene acetate production technology.

Tuberculosis, caused by mycobacteria, continues to pose a substantial public health threat. Mycobacteria typically use cholesterol from the membranes of host macrophages as a carbon and energy source. Most genes that control cholesterol degradation are regulated by KstR, which is highly conserved in Mycobacterium tuberculosis and Mycobacterium smegmatis. Through bioinformatic analysis, we found a typical global nitrogen regulator (GlnR)-binding motif (CCGAC-AACAGT-GACAC) in the promoter region of kstR of M. smegmatis, and we determined its binding activity in vitro using electrophoretic mobility shift assays. Using RT-qPCR, we found that nine genes involved in side-chain or sterol-ring oxidation were upregulated in a ΔglnR M. smegmatis strain compared to the WT strain and glnR-complemented strains under nitrogen limitation. ATP assays in macrophages revealed that coordinated GlnR-KstR regulation significantly reduced the viability of M. smegmatis in macrophages. Thus, we found that various genes involved in cholesterol catabolism are regualted by GlnR via KstR in response to environmental nitrogen, and that they further affect the invasive ability of M. smegmatis. These findings revealed a novel regulatory mechanism of cholesterol catabolism, which may be useful in the development of new strategies for controlling tuberculosis. This article is protected by copyright. All rights reserved.

Previously, Cu2O cubes have been shown to remain photocatalytically inert toward methyl orange degradation even after surface decoration with ZnO, ZnS, CdS, and Ag3PO4 nanostructures. Surprisingly, when Ag2S nanoparticles are lightly deposited on Cu2O cubes as seen through scanning electron microscopy (SEM) images, the heterostructures become highly photocatalytically active. X-ray diffraction (XRD) patterns show mainly Cu2O diffraction peaks due to lightly deposited Ag2S, but Ag2S peaks can emerge with increased Ag2S deposition. X-ray photoelectron spectroscopy (XPS) analysis also supports Ag2S formation on Cu2O crystals. The Ag2S-deposited Cu2O octahedra and rhombic dodecahedra show the expected activity enhancement. Electron paramagnetic resonance (EPR) measurements, as well as electron, hole, and radical scavenger tests, all confirmed the emergence of photocatalytic activity from the Ag2S-Cu2O cubes. Photoluminescence lifetimes are shortened after Ag2S deposition. Electrochemical impedance measurements revealed a large decrease in charge transfer resistance for Cu2O cubes after the Ag2S deposition. Unexpectedly, the separately synthesized Ag2S particles are also photocatalytically inactive. No specific lattice planes of Ag2S are formed directly over the {100} face of Cu2O. Diffuse reflectance and ultraviolet photoelectron spectral data were used to construct band diagrams of different Cu2O crystals and Ag2S nanoparticles. A Z-scheme charge transfer mechanism may be involved at the heterojunction interface to promote charge carrier separation. However, to explain the sudden appearance of photocatalytic activity from the Ag2S-deposited Cu2O cubes, a large change in the {100} surface band bending after Ag2S deposition should be used. This work illustrates that an unusual photocatalytic outcome is possible to semiconductor heterojunctions, where two photocatalytically inert components can become highly active when joined together.

Clinical cases have reported pulmonary arterial structural and functional abnormalities in patients with Kawasaki disease (KD); however, the underlying mechanisms are unclear. In this study, a KD rat model was established via the intraperitoneal injection of Lactobacillus casei cell wall extract (LCWE). The results showed that pulmonary arterial functional and structural abnormalities were observed in KD rats. Furthermore, proliferative endoplasmic reticulum stress (ER stress) was observed in the pulmonary arteries of KD rats. Notably, the level of lipocalin-2 (Lcn 2), a trigger factor of inflammation, was remarkably elevated in the plasma and lung tissues of KD rats; increased Lcn 2 levels following LCWE stimulation may result from polymorphonuclear neutrophils (PMNs). Correspondingly, in cultured pulmonary artery smooth muscle cells (PASMCs), Lcn 2 markedly augmented the cleavage and nuclear localization of activating transcription factor-6 (ATF6), upregulated the transcription of glucose regulated protein 78 (GRP78) and neurite outgrowth inhibitor (NOGO), and promoted PASMCs proliferation. However, proapoptotic C/EBP homologous protein (CHOP) and caspase 12 levels were not elevated. Treatment with 4-phenyl butyric acid (4-PBA, a specific inhibitor of ER stress) inhibited PASMCs proliferation induced by Lcn 2 and attenuated pulmonary arterial abnormalities and right ventricular hypertrophy and reduced right ventricular systolic pressure in KD rats. In conclusion, Lcn 2 remarkably facilitates proliferative ER stress in PASMCs, which probably accounts for KD-related pulmonary arterial abnormalities.

In recent years, all-inorganic perovskite materials have set off a research boom owing to features, such as good thermal stability, suitable bandgap, and fascinating optical properties. However, the power conversion efficiency (PCE) and the ambient stability of all-inorganic perovskite solar cells still remain a challenge. Herein, we investigate the effect of the addition of InI3 into CsPbI3 film on the corresponding device. InI3 incorporation could retard the crystallization process and control the growth rate of CsPbI3 polycrystalline films, yielding a high quality film with large grains and few voids. The increment in electrostatic potential and the reduction of carrier recombination enabled the open-circuit voltage of fabricated perovskite solar cell to be increased from 0.89 to 0.99 V. The champion device delivered a power conversion efficiency of 17.09%, which is higher than 14.36% for the reference device. And the InI3-included solar cell without any encapsulation retained 77% of its original efficiency after 860 h aging at room temperature in N2 condition.

Growing evidence now suggests that circulating tumour DNA (ctDNA) has great potential as a non-invasive biomarker for disease monitoring, since ctDNA carries tumour-specific modifications. In particular, monitoring ctDNA has important implications for identifying patients with haematological malignancies at clinical risk of disease progression. We hereby describe three patients with B-cell non-Hodgkin lymphoma and investigate the clinical value of sequential ctDNA profiling for the early detection of tumour relapse. Somatic mutations in diagnostic tumour biopsy samples of these three patients were identified by applying high-throughput next-generation sequencing. Droplet digital PCR probes and primers were designed and tested for each hotspot mutation. Serial ctDNA analysis was subsequently conducted among these three patients. We found that the longitudinal monitoring of plasma ctDNA could predict for at least one month in advance compared with flow cytometry, cytology and conventional imaging modalities. Therefore, our results support liquid biopsy based on ctDNA as a non-invasive complementary modality to other detection methods for detecting early relapse and contribute to more precise management for non-Hodgkin lymphoma patients.

Creating small-molecule antivirals specific for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) proteins is crucial to battle coronavirus disease 2019 (COVID-19). SARS-CoV-2 main protease (Mpro) is an established drug target for the design of protease inhibitors. We performed a structure-activity relationship (SAR) study of noncovalent compounds that bind in the enzyme's substrate-binding subsites S1 and S2, revealing structural, electronic, and electrostatic determinants of these sites. The study was guided by the X-ray/neutron structure of Mpro complexed with Mcule-5948770040 (compound 1), in which protonation states were directly visualized. Virtual reality-assisted structure analysis and small-molecule building were employed to generate analogues of 1. In vitro enzyme inhibition assays and room-temperature X-ray structures demonstrated the effect of chemical modifications on Mpro inhibition, showing that (1) maintaining correct geometry of an inhibitor's P1 group is essential to preserve the hydrogen bond with the protonated His163; (2) a positively charged linker is preferred; and (3) subsite S2 prefers nonbulky modestly electronegative groups.

This work investigates the photovoltaic properties of polymers that include different carbazole blocks as electron donors (D) but the same benzothiadiazole derivative as the electron acceptor (A). Five D–A copolymers are studied with ultrafast intramolecular exciton splitting and recombination dynamics to acquire the single-molecule structure and their photovoltaic performance relationship. The photovoltaic parameters such as energy level, optical band gap, and light-harvesting ability are highly dependent on the molecular structure of the donor monomer (including their appended flexible alkyl chain). Branched or linear alkyl groups on the same D block obviously vary the polymer steady-state absorption spectra and film morphology. For organic solar cells, this work allows tuning and control of the ultrafast dynamics, implying photovoltaic material design in the future.

All-inorganic-based perovskites achieved by replacing the organic component with cesium (Cs) have drawn more attention because of their intrinsic inorganic stability. However, the cell efficiency in all-inorganic perovskite solar cells is still far below that in organic-inorganic hybrid perovskite-based devices. Here, we develop a new strategy to mediate the CsPbI2Br crystallization by directly doping copper(II) bromide (CuBr2) into a perovskite precursor. The incorporation of CuBr2 played a role in retarding the crystallization dynamics process of CsPbI2Br film, resulting in a high-quality all-inorganic perovskite film with enlarged grain size, improved carrier mobilities, and reduced trap states. The fabricated perovskite solar cells delivered a champion power conversion efficiency of 16.15%, which is the highest efficiency in CsPbI2Br based all-inorganic perovskite solar cells and largely higher than 13.24% for pristine CsPbI2Br based device. The developed doping method paves a new route to fabricate high-performance all-inorganic perovskite solar cells.

Aims In myocardial ischemia-reperfusion (MI/R) injury, impaired autophagy function worsens cardiomyocyte death. AMP-activated protein kinase (AMPK) is a heterotrimeric protein that plays an important role in cardioprotection and myocardial autophagic function. AMPKα1 and α2 are localized primarily in the cytoplasm and nucleus, respectively, in cardiomyocytes, but the isoform-specific autophagy regulation of AMPK during MI/R remains unclear. Materials and methods An MI/R model was built, and the protein expression of AMPKα1/α2, p-AMPK, mTOR, p-mTOR, TFEB, p-FoxO3a, SKP2, CARM1, TBP, Atg5, LAMP2, LC3B, and p62 during ischemia and reperfusion was determined by western blotting. Recombinant adeno-associated virus (serotype 9) vectors carrying tandem fluorescent-tagged LC3 or mRFP-GFP-LC3/GFP-LC3 were used to evaluate the autophagy status. AMPKα2 knockout mice were used for in vivo studies. Key findings Both cytoplasmic AMPKα1 and nuclear α2 subunit expression decreased during the reperfusion period, which led to AMPKα1-mTOR-TFEB and AMPKα2-Skp2-CARM1-TFEB signaling inhibition, respectively. The decreased TFEB level during reperfusion suppressed autophagy. Metformin could activate both the AMPKα1- and α2- mediated pathways, thus restoring autophagy flux during reperfusion. Nevertheless, in AMPKα2 knockout mice, nuclear α2-regulated Skp2-CARM1-TFEB signaling was inhibited, while α1-related signaling was comparatively unaffected, which partially impaired metformin-enhanced autophagy. Significance Our study suggests that metformin had the dual effects of promoting both cytoplasmic AMPKα1- and nuclear AMPKα2-related signaling to improve autophagic flux and restore cardiac function during MI/R.

Objective We investigated whether Piezo1 could regulate oxygen-glucose deprivation/reoxygenation injury of neurons through Ca2+/calpain signaling. Methods Piezo1 expression in rat brain cortex and PC12 cells were confirmed by immunohistochemistry, immunofluorescence and Western blotting. The effects of Yoda1 and GsMTx4 on OGD/R-induced decrease in cell viability, increase in cell apoptosis and activation of downstreaming Ca2+/calpain signaling were investigated. Furthermore, calpain signaling was inhibited by PD151746 to see whether Ca2+/calpain signaling participated in the neurotoxic effects of Piezo1 activation. Results Piezo1 expression was increased in rat cerebral cortex after ischemia/reperfusion and in PC12 cells after OGD/R. Activation of Piezo1 by Yoda1 enhanced OGD/R-induced cell viability inhibition, apoptosis, increase intracellular calcium levels and enhanced calpain activity while GsMTx4 showed the opposite effects. The effects of Piezo1 activation on cell viability and apoptosis were reversed by PD151746. Conclusion Piezo1 could regulate neuron oxygen-glucose deprivation/reoxygenation injury via activation of Ca2+/calpain signaling.

In inverted perovskite solar cells, poly(3,4-ethylene dioxythiophene) (PEDOT) and poly(styrene sulfonate) (PSS) are traditional hole transport materials. In such cells, functional improvement is becoming harder to achieve for the device. However, in this study, a novel process was found to be effective using the argon-plasma treatment, in which the ion cluster was used to scour the PEDOT:PSS surface instead of the traditional bombardment method. By an ideal plasma-generation power and treatment time (1800 J), the largest photoelectric conversion efficiency (PCE) of the device of PED (PEDOT:PSS surface being parallel to the plasma-generation electric field direction) reaches 14.8% with an improvement of 23.3% compared to the VED (vertical to the plasma electric field direction) device whose PCE is 13.31%, while the PCE of the reference is 12.0%. As per the physical mechanism, both PED and VED treatment can increase the surface free energy and roughness to result in a suitable hydrophilicity and larger grain size of the perovskite film. With the change in the ratio of PEDOT and PSS by the plasma treatment, the conductivity of the film also increases observably. Furthermore, since PED has the furrowing effect on the PEDOT:PSS surface, the ordered crystallization leads to perovskite films with few pinholes, and improves the abovementioned properties better than VED.

Here, this study presents a simply synthesis proposal for perylene monoimides with traditional wet solution reaction in one step from commercially available perylene dianhydride and the moderate yield has been got. Their dimmer or ethynylene or butadiynylene bridged perylene derivatives were then developed. The work expanded the structural diversity of these dye molecules to a multifunctional class of n-type semiconductor materials. The high LUMO level (−3.83∼-3.96 eV) reduced the energy loss by associating wide bandgap polymer refer to PC71BM (−4.04 eV). Using these compounds as non-fullerene electron acceptors constructs the inverted solar cells, the power conversion efficiency is up to 1.45% for wide band gap polymer donor with an ultrathin active layer thickness of 30 nm.

Background: Cardiac autophagic flux is impaired during myocardial ischemia/reperfusion (MI/R). Impaired autophagic flux may exacerbate MI/R injury. Charged multivesicular body protein 2B (CHMP2B) is a subunit of the endosomal sorting complex required for transport (ESCRT-III) complex that is required for autophagy. However, the reverse role of CHMP2B accumulation in autophagy and MI/R injury has not been established. The objective of this article is to elucidate the roles of AMP-activated protein kinase (AMPK)/atrogin-1 pathways in inhibiting CHMP2B accumulation in ischemia–reperfusion injury.Methods: Male C57BL/6 mice (3–4 months) and H9c2 cardiomyocytes were used to evaluate MI/R and hypoxia/reoxygenation (H/R) injury in vivo and in vitro, respectively. MI/R was built by a left lateral thoracotomy and occluded the left anterior descending artery. H9c2 cells were firstly treated in 95% N2 and 5% CO2 for 15 h and reoxygenation for 1 h. Metformin (100 mg/kg/d) and CHMP2B (Ad-CHMP2B) transfected adenoviruses were administered to the mice. The H9c2 cells were treated with metformin (2.5 mM), MG-132 (10 μM), bafilomycin A1 (10 nM), and compound C (20 μM).Results: Autophagic flux was found to be inhibited in H/R-treated cardiomyocytes and MI/R mice, with elevated cardiac CHMP2B accumulation. Upregulated CHMP2B levels in the in vivo and in vitro experiments were shown to inhibit autophagic flux leading to the deterioration of H/R-cardiomyocytes and MI/R injury. This finding implies that CHMP2B accumulation increases the risk of myocardial ischemia. Metformin suppressed CHMP2B accumulation and ameliorated H/R-induced autophagic dysfunction by activating AMPK. Activated AMPK upregulated the messenger RNA expression and protein levels of atrogin-1, a muscle-specific ubiquitin ligase, in the myocardium. Atrogin-1 significantly enhanced the interaction between atrogin-1 and CHMP2B, therefore, promoting CHMP2B degradation in the MI/R myocardium. Finally, this study revealed that metformin-inhibited CHMP2B accumulation induced autophagic impairment and ischemic susceptibility in vivo through the AMPK-regulated CHMP2B degradation by atrogin-1.Conclusion: Impaired CHMP2B clearance in vitro and in vivo inhibits autophagic flux and weakens the myocardial ischemic tolerance. Metformin treatment degrades CHMP2B through the AMPK-atrogin-1-dependent pathway to maintain the homeostasis of autophagic flux. This is a novel mechanism that enriches the understanding of cardioprotection.

Electrochemical H charging, hydrogen permeation, and hydrogen-induced cracking (HIC) behavior of 690 MPa grade steel substrate and different heat-treatment states (annealed, quenched, normalized, tempered) are investigated by cyclic voltammetry (CV), hydrogen permeation, electrochemical H charging, and slow strain rate tensile test (SSRT). The results show that hydrogen diffuses through the steel with the highest rate in base metal and the lowest rate in annealed steel. The hydrogen-induced cracks in base metal show obvious step shape with tiny cracks near the main crack. The cracks of annealed steel are mainly distributed along pearlite. The crack propagation of quenched steel is mainly transgranular, while the hydrogen-induced crack propagation of tempered steel is along the prior austenite grain boundary. HIC sensitivity of base metal is the lowest due to its fine homogeneous grain structure, small hydrogen diffusion coefficient, and small hydrogen diffusion rate. There are many hydrogen traps in annealed steel, such as the two-phase interface which provides accommodation sites for H atoms and increases the HIC susceptibility.

Exposure to particulate matter 2.5 (PM2.5) potentially triggers airway inflammation by activating nuclear factor-κB (NF-κB). Sirtuin 2 (SIRT2) is a key modulator in inflammation. However, the function and specific mechanisms of SIRT2 in PM2.5-induced airway inflammation are largely understudied. Therefore, this work investigated the mechanisms of SIRT2 in regulating the phosphorylation and acetylation of p65 influenced by PM2.5-induced airway inflammation and bronchial hyperresponsiveness. Results revealed that PM2.5 exposure lowered the expression and activity of SIRT2 in bronchial tissues. Subsequently, SIRT2 impairment promoted the phosphorylation and acetylation of p65 and activated the NF-κB signaling pathway. The activation of p65 triggered airway inflammation, increment of mucus secretion by goblet cells, and acceleration of tracheal stenosis. Meanwhile, p65 phosphorylation and acetylation, airway inflammation, and bronchial hyperresponsiveness were deteriorated in SIRT2 knockout mice exposed to PM2.5. Triptolide (a specific p65 inhibitor) reversed p65 activation and ameliorated PM2.5-induced airway inflammation and bronchial hyperresponsiveness. Our findings provide novel insights into the molecular mechanisms underlying the toxicity of PM2.5 exposure. Triptolide inhibition of p65 phosphorylation and acetylation could be an effective therapeutic approach in averting PM2.5-induced airway inflammation and bronchial hyperresponsiveness.

Palmitic acid (PA)-induced myocardial injury is considered a critical contributor to the development of obesity and type 2 diabetes mellitus (T2DM)-related cardiomyopathy. However, the underlying mechanism has not been fully understood. Here, we demonstrated that PA induced the cell death of H9c2 cardiomyoblasts in a dose- and time-dependent manner, while different ferroptosis inhibitors significantly abrogated the cell death of H9c2 cardiomyoblasts and primary neonatal rat cardiomyocytes exposed to PA. Mechanistically, PA decreased the protein expression levels of both heat shock factor 1 (HSF1) and glutathione peroxidase 4 (GPX4) in a dose- and time-dependent manner, which were restored by different ferroptosis inhibitors. Overexpression of HSF1 not only alleviated PA-induced cell death and lipid peroxidation but also improved disturbed iron homeostasis by regulating the transcription of iron metabolism-related genes (e.g., Fth1, Tfrc, Slc40a1). Additionally, PA-blocked GPX4 protein expression was evidently restored by HSF1 overexpression. Inhibition of endoplasmic reticulum (ER) stress rather than autophagy contributed to HSF1-mediated GPX4 expression. Moreover, GPX4 overexpression protected against PA-induced ferroptosis, whereas knockdown of GPX4 reversed the anti-ferroptotic effect of HSF1. Consistent with the in vitro findings, PA-challenged Hsf1-/- mice exhibited more serious ferroptosis, increased Slc40a1 and Fth1 mRNA expression, decreased GPX4 and TFRC expression and enhanced ER stress in the heart compared with Hsf1+/+ mice. Altogether, HSF1 may function as a key defender against PA-induced ferroptosis in cardiomyocytes by maintaining cellular iron homeostasis and GPX4 expression.

Although dietary α-linolenic acid (ALA) or linolenic acid (LA) intake was reported to be epidemiologically associated with a lower prevalence of hypertension, recent clinical trials have yielded conflicting results. Comparable experimental evidence for the roles of these two different fatty acids is still lacking and the underlying mechanisms need to be further elucidated. Our data showed that ALA but not LA supplementation alleviated systolic blood pressure elevation and improved ACh-induced, endothelium-dependent vasodilation in both spontaneously hypertensive rats (SHRs) and AngII-induced hypertensive mice. In addition, SHRs displayed reduced vascular Sirtuin 3 (SIRT3) expression, subsequent superoxide dismutase 2 (SOD2) hyperacetylation and mitochondrial ROS overproduction, all of which were ameliorated by ALA but not LA supplementation. In primary cultured endothelial cells, ALA treatment directly inhibited SIRT3 reduction, SOD2 hyperacetylation, mitochondrial ROS overproduction and alleviated autophagic flux impairment induced by AngII plus TNFα treatment. However, these beneficial effects of ALA were completely blocked by silencing SIRT3. Restoration of autophagic flux by rapamycin also inhibited mitochondrial ROS overproduction in endothelial cells exposed to AngII plus TNFα. More interestingly, SIRT3 KO mice developed severe hypertension in response to a low dose of AngII infusion, while ALA supplementation lost its anti-hypertensive and endothelium-protective effects on these mice. Our findings suggest that ALA but not LA supplementation improves endothelial dysfunction and diminishes experimental hypertension by rescuing SIRT3 impairment to restore autophagic flux and mitochondrial redox balance in endothelial cells., Schematic diagram of the mechanisms whereby α-linolenic acid protects against endothelial dysfunction and hypertension.

In order to further enhance the performance of the components previously treated by plasma nitriding (PN) and meet the technical requirements proposed by the cooperative enterprise, plasma boron-nitriding (PNB) was primarily developed for 42CrMo4 steel at 520 °C for 6 h by adding a little Ferroboron around the samples during the process of plasma nitriding. The results show that plasma boron-nitriding (PNB) can significantly increase the surface hardness of the sample from 750HV0.05 to 1002HV0.05 due to the formation of very hard borides of FeB and Fe2B, and the thickness of compound layer is increased from 18.78um to 29.44um, the effective diffusion layer is increased from 265um to 355um, which is equivalent to an increase of nitriding efficiency by about 35%. At the same time, the wear resistance of the samples treated by PNB is significantly enhanced, the wear marks turns to be much shallower and narrower, and the wear rate is decreased from 3.06 mg/cm2 to 1.02 mg/cm2.

The poor cycle performance caused by the shuttle effect of polysulfides is the main challenge that affects the practical implementation for lithium-sulfur (Li-S) batteries. Here, a unique long-range and phosphorus-deficient phosphorene (BP4-x) framework featured with 3D ordered sponge (3DOS) architecture and carbon nanotubes (CNTs) embedding is developed, which serves as a high-performance sulfur immobilizer and catalytic promoter for polysulfide conversion. The 3DOS architecture comprise ultrathin and large BP nanosheets and the semi-connected nanosheets afford open channels for fast ion/mass transfer. Simultaneously, CNTs embedded within the BP4-x skeleton as a conductive network can improve the conductivity of the materials. The Li-S batteries constructed with these advanced features exhibits an enhanced capacity of 1120.1 mAh g−1 with a high coulombic efficiency of similar to 99.4%, and great rate capability of 660.1 mAh g−1 at 4 C. Our study illustrates potential application of a metal-free phosphorene catalyst for high energy storage devices.

Lithium sulfur (Li-S) battery is considered as a promising alternative for the development of battery technologies. However, the shuttle effect seriously limits its practical use. Herein, hollow tubular graphene-like carbon nitride (Tg-C3N4) is synthesized and utilized as a functional interlayer to inhibit shuttling effect and promote catalytic kinetics. Both experiments and DFT calculations together suggest that N-doping enhances the electron transfers between Tg-C3N4and LiPSs, leading to improved chemical adsorptions and catalytic effects towards the redox conversions of the active sulfur species. Besides, Tg-C3N4delivers a unique hollow tubular architecture with massive ion transfer pathways and fully exposed active interfaces. In addition, the abundant C-N heteroatomic structures also impose strong chemical immobilization toward lithium polysulfides. Benefiting from these unique superiorities, the cell with the Tg-C3N4-modified separator exhibits a reversible capacity of 494 mAh g-1after 500 cycles at 1 C with a negligible capacity decay of 0.085% per cycle, indicating an efficient strategy toward high-performance modified separators.

Photovoltaic performance of planar perovskite hybrid solar cells (pero-HSCs) has been improved by mixing CH3NH3PbIxCl3−x and an electron donor polymer [N-9′′-hepta-decanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiaz-ole)] (PCDTBT). PCDTBT contains lone pairs of electrons due to the presence of S and N atoms, which could passivate the trap states of the perovskite layer and thus reduce the number of film defects. A Stonehenge-like structure could be formed by the interaction of CH3NH3PbIxCl3−x and PCDTBT, developing more ordered orientation crystallization and a high quality film morphology. The doped solar cells are characterized by their excellent photovoltaic properties and enhanced stability. When the doping concentration is 0.3 mg mL−1, the fabricated solar cell device exhibits an outstanding power conversion efficiency (PCE) of 15.76%, which represents a significant improvement with respect to the magnitude of 16% obtained for the reference device.

Because of the differences in the position and degree of fluorine substitution, four fluorinated DSA (9,10-distyrylanthracene) derivatives, namely 9,10-bis(4-fluorostyryl)anthracene (4-BFSA), 9,10-bis(3-fluorostyryl)anthracene (3-BFSA), 9,10-bis(3,5-difluorostyryl)anthracene (BDFSA) and 9,10-bis(3,4,5-trifluorostyryl)anthracene (BTFSA), display different crystal packing and photophysical properties in the solid state. Furthermore, the photophysical properties in solution have been investigated. The results show that all the four compounds exhibit tunable aggregation-induced enhanced emission (AIEE) properties. Notably, DSA, 4-BFSA, 3-BFSA and BDFSA display solvatochromic properties. The relationship between their structures and photophysical properties was further discussed. This work has demonstrated that depending on the amount and position, fluorine substitution can tune the structures and photophysical properties of DSA effectively.

The method of preparing perovskite films in ambient air is of great importance to commercializing high-performance planar perovskite solar cells (PSCs). Herein, an efficient and stable inverted planar PSC has been prepared via a simple solution method in ambient air. A suitable vanadium oxide (V2Ox) aqueous solution is mixed with a CH3NH3PbI3−xClx precursor solution, resulting in an improvement in the CH3NH3PbI3−xClx film. Perovskite films with large crystal sizes could be obtained using V2Ox additives. The improvement in the performance of perovskite films is conducive to the separation and transmission of charge carriers. For PSCs, the highest power conversion efficiency (PCE) of 16.14% was obtained by controlling the proportion of V2Ox additives in ambient air. It is via a physical mechanism that V2Ox particles are dispersed in the perovskite crystal boundary, and the heterogeneous structure between CH3NH3PbI3−xClx and V2Ox is formed. In addition, the slow migration of iodide ions and stability of the perovskite films are also achieved. What merits more attention is that the PSCs with CH3NH3PbIxCl3−x:V2Ox (2.5 wt%) still maintain a high PCE after being stored for 1000 h, more than 70% of the initial one.

Myocardial ischemia-reperfusion (IR) injury during acute myocardial infarction or open-heart surgery would promote oxidative stress, leading to the accumulation of reactive aldehydes that cause cardiac damage. It has been well demonstrated that aldehyde dehydrogenase (ALDH)-2 is an important cardioprotective enzyme for its central role in the detoxification of reactive aldehydes. ALDH2 activation by small molecule activators is a promising approach for cardioprotection for myocardial IR injury.

The crystalline quality of the perovskite film plays a key role in improving the optoelectronic properties and the performance of planar perovskite hybrid solar cells (PSCs). In this study, a methodology employing post-annealing microwave treatment (MPAT) for fine tuning the crystallization of perovskite films is proposed. It was found that the microwave induced electromagnetic waves result in the vibration of dipoles and ions at high frequencies in perovskite crystals, which catalyzes the Ostwald ripening process and results in good quality perovskite films. High quality perovskite films were obtained after being subjected to MPAT with 350 watts of power for 25 seconds. The resulting films, demonstrating an inverted solar cell architecture, and showed a champion efficiency of 13.39%. This was a significant improvement in the performance compared to those of the devices employing films without MPAT treatment (PCE = 11.5%). The MPAT provides a way to prepare high quality perovskite films that are of particular significance for the manufacturing of large area perovskite solar cells.

This work proposes a new perovskite solar cell structure by inserting the double modified interlayers consisting of the 4,7-diphenyl-1,10-phenanthroline (Bphen) and cesium carbonate (Cs2CO3)-MoO3 layer between perovskite (CH3NH3PbI3−xClx)/PCBM (phenyl-C61-butyric acid methylester) and an Ag electrode. The double interlayers improve the photovoltaic efficiency to 15.59%, which is higher than that of reference devices with Bphen (13.41%) or alone, the champion PCE of 16.01% is obtained. The enhanced opening circuit voltage (Voc) is ascribed as the main factor to improve the efficiency. Further studies show, the reduced work function of cathode by means of the Cs2CO3-MoO3 could effectively extract the electrons and reduce the carrier recombination and thus result in a higher Voc.

Protein–ligand interaction detection without disturbances (e.g., surface immobilization, fluorescent labeling, and crystallization) presents a key question in protein chemistry and drug discovery. The emergent technology of transient induced molecular electronic spectroscopy (TIMES), which incorporates a unique design of microfluidic platform and integrated sensing electrodes, is designed to operate in a label-free and immobilization-free manner to provide crucial information for protein–ligand interactions in relevant physiological conditions. Through experiments and theoretical simulations, we demonstrate that the TIMES technique actually detects protein–ligand binding through signals generated by surface electric polarization. The accuracy and sensitivity of experiments were demonstrated by precise measurements of dissociation constant of lysozyme and N-acetyl-d-glucosamine (NAG) ligand and its trimer, NAG3. Computational fluid dynamics (CFD) computation is performed to demonstrate that the surface’s electric polarization signal originates from the induced image charges during the transition state of surface mass transport, which is governed by the overall effects of protein concentration, hydraulic forces, and surface fouling due to protein adsorption. Hybrid atomistic molecular dynamics (MD) simulations and free energy computation show that ligand binding affects lysozyme structure and stability, producing different adsorption orientation and surface polarization to give the characteristic TIMES signals. Although the current work is focused on protein–ligand interactions, the TIMES method is a general technique that can be applied to study signals from reactions between many kinds of molecules., NAG-binding changes lysozyme adsorption orientation on Au(111) surface in water and introduces different surface electric polarization signals in transition state, which is used to detect protein−ligand interactions.

Mixed Pb-In perovskite solar cells are fabricated by using lead(II) chloride and indium(III) chloride with methylammonium iodide. A maximum power conversion efficiency as high as 17.55% is achieved owing to the high quality of perovskites with multiple ordered crystal orientations.

Perovskite crystallization and interface engineering are regarded as the most crucial factors in achieving high-performance planar heterojunction (PHJ) perovskite solar cells (PSCs). Herein, we demonstrate a thin perylene underlayer via a solution-processable method. By using branch-shaped perylene film as a seed-mediated underlayer, crystalline perovskites with fabric morphology can be formed, which allows for obvious improvement in absorption by a light scattering effect. With its deep highest occupied molecular orbital (HOMO) level, perylene also plays an important role in the energy-level tailoring of poly(3,4-ethylenedioxythiophene): poly(styrenesulphonate) (PSS) and CH3NH3PbIxCl3-x. In addition, perylene and perovskites form a fully crystalline heterojunction, which is beneficial for minimizing the defect and trap densities. Due to these merits, a maximum power conversion efficiency of 17.06% with improved cell stability is achieved. The finding in this work provides a simple route to control perovskite crystallizaition and to optimize the interfaces in PHJ PSCs simultaneously.

Introduction: Data on relationship between lipoprotein(a) [Lp(a)] and non-ischemic heart dysfunction are limited. This study is aimed to assess the association between Lp(a) and left ventricular systolic dysfunction in a Chinese population of patients with hypertension and without coronary artery disease (CAD). Material and methods: This cross-sectional study included 1611 patients with hypertension and without CAD in China. The factors associated with left ventricular ejection fraction (LVEF) were evaluated using univariate and multivariate analysis. Results : A higher percentage of hypertensive patients with LVEF

Salt formation is a very common and effective method of improving a drug's physicochemical properties such as hygroscopicity and physical stability at different humidity conditions. Aqueous solubility is another important parameter that can be improved by salt formation; however this strategy has not yet been evaluated for the important alkaloid drug, Vinpocetine. A poorly water-soluble basic drug (water solubility value≈ 5 μg/ml and pKa value of 7.31), vinpocetine was converted into two novel salts in this work, with perchloric acid and phosphoric acid in a 1: 1 M ratio. However, an unexpected phase transformation occurred in one of the salts after the stability test, which is a major concern in studies on dosage form. The conversion of the salt to free base could be related to the temperature-humidity profile of the type II salt (formed by vinpocetine and phosphoric acid). When the temperature was more than 70 °C under high humidity conditions of more than 80%, the phase transformation occurred immediately. To gain further understanding of this phenomenon, single crystals of the two novel salts were prepared and characterized by single crystal X-ray diffraction, Powder-XRD, infrared spectroscopy, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Constituents of the crystalline phase were also investigated in terms of Hirshfeld surface. The structures were found to be stabilized by H⋯H, C–H⋯O, O–H⋯N and C–H⋯π intermolecular interactions. Our stability studies showed that both these two novel salts could improve the stability of vinpocetine, however the type I salt (formed by vinpocetine and perchloric acid) offers more advantages. This finding will provide valuable information for vinpocetine dosage form development.

Interface engineering is an efficient method for improving the performance of planar perovskite solar cells (PSCs). In this paper, the performance of PSCs was improved significantly by introducing 4,7-diphenyl-1,10-phenanthroline (Bphen) doped with bis(2-methyldibenzo-[f,h]quinoxaline) (Ir(MDQ)2(acac)) to modify the interface between perovskite (CH3NH3PbI3−xClx)/PCBM (phenyl-C61-butyric acid methyl ester) and an Ag electrode. The power conversion efficiency (PCE) was enhanced up to 15.87%, compared with 10.77% for the reference device without interlayer modification. It was found that the enhanced PCE was attributed to the better interface contact between the perovskite and Ag cathode. A suitable interface roughness is beneficial for reducing the leakage current and the probability of carrier recombination, resulting in an enhanced fill factor and thus improved device efficiency.

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)–molybdenum oxide (MoOx) composite films are used as hole transport layers in planar perovskite solar cells (PSCs) by simply incorporating solution-processed MoOx powders into a PEDOT:PSS solution. Compared to PEDOT:PSS based PSCs, the PEDOT:PSS–MoOx based PSC exhibits an obvious improvement in conversion efficiency, open circuit voltage, and fill factor. The morphology of perovskite films indicates that the film coverage has been improved due to the introduction of MoOx nanospots into the underlayer, which are regarded as the growing sites of the crystal nucleus of the perovskites during annealing. A PEDOT:PSS–MoOx based device with a power conversion efficiency of over 15% has been achieved, suggesting that the PEDOT:PSS–MoOx film is efficient as a hole transport layer in obtaining highly efficient planar perovskite solar cells.

To improve the severe hot tearing susceptibility of TiB 2 reinforced Al-5Cu matrix composites, the present research investigated the influence of Y on the hot tearing susceptibility of 6TiB 2 /Al-5Cu composite. For the composite added with Y, the solidification temperature range was shortened, which was caused by the novel τ 1 -Al 8 Cu 4 Y phase. The grain size of 6TiB 2 /Al-5Cu composite was 39.8 µm. The addition of Y promoted the grain refinement, and the grain sizes were 36.33, 33.42 and 26.77 µm for 6TiB 2 /Al-5Cu with 0.2 wt.%, 0.5 wt.% and 1 wt.% Y, respectively. The decrease of solidification temperature range and grain size was beneficial to the hot tearing susceptibility improvement. Furthermore, the hot tearing initiation force increased from 44 to 288 N, when 1 wt.% Y was added in 6TiB 2 /Al-5Cu. For the above significant influence, the hot tearing susceptibility values were reduced by 12.2 wt.%, 57.7 wt.% and 66.8 wt.% for 6TiB 2 /Al-5Cu with 0.2 wt.%, 0.5 wt.% and 1 wt.% Y, accordingly.

Two copper coordination polymers have been synthesized by using flexibly carboxylic ligand (5,5′-((1,4-phenylenebis(methylene))bis(oxy))diisophthalic acid) H4L. Structural transformations of these two coordination polymers have happened during the crystallization. By controlling the reaction time, compounds 1 and 2 can be isolated successfully, resulting in 1D and 2D structure respectively. 1D ring-like infinite chain [Cu1.5(HL)(py)2(H2O)]n·nH2O (1) was an intermediate phase during the formation of the final 2D hexagon layer [Cu2(L)(py)4(H2O)4]n·nH2O (2). To further understand the structural relationship of 1 and 2, the structural transformation between these two compounds have also been explored. Furthermore, the Quartz Crystal Microbalance (QCM) sensor modified with compound 2 has good selectivity and a high response to benzene vapor.

A novel and highly selective electrochemical sensing platform (ZnCl2-CF/GCE) based on combination of kiwi skin and zinc chloride nanoparticles was developed for the simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA). The constructed electrode shows a high surface area and micro-mesoporous structure. And the electrochemical behaviors of the electrode were further explored by cyclic voltammetry (CV), impedance analysis (EIS), and differential pulse voltammetry (DPV). Under the optimal conditions, the ZnCl2-CF provides a high sensitivity and selective signaling in the co-existence system of AA, DA, and UA with linear response ranges of 0.05–200 μM, 2–2000 μM, and 1–2500 μM, respectively. The detection limits (S/N = 3) were calculated to be 0.02 μM, 0.16 μM, and 0.11 μM, respectively. In addition, the method has been successfully applied to determine AA, DA, and UA in real samples, which provides potential applications in further sensing study.

The flashover at the solid-liquid interface is the main dielectric failure in the cryogenic insulation system, which has great relation with the carrier mobility. In this paper, epoxy$/\mathrm {B}\mathrm {N}$(boron nitride)/Graphene composites with different contents were prepared and the surface potential decay (SPD) method was employed to analyze the transit time and the carrier mobility. The experimental results indicate that the behaviors of surface potential and carrier mobility are affected by specimen temperature. Obtained results show that BN and Graphene particles can affect the carrier mobility and modulate the discharge speed, which may further influence the flashover voltage at solid-liquid interface at cryogenic temperature.

Combination of active pharmaceutical ingredients, trans-4-[(2-amino-3,5-dibrobenzyl) amino] cyclohexanol (AMB) and some organic acids, e.g., p-hydroxybenzoic acid (PHBA), m-hydroxybenzoic acid (MHBA), and 3,4-dihydroxy benzoic acid (DHBA), yield three novel co-crystals characterized by X-ray single-crystal, Fluorescence spectroscopy and thermal analysis (DSC and TGA), which included co-crystal 1 with 2:2: 1 stoichiometry of AMB, PHBA and H 2 O, co-crystal 2 with 1:1 stoichiometry of AMB and MHBA, and co-crystal 3 with 1:1:1 stoichiometry of AMB, DHBA and CH 3 OH. Constituents of the co-crystalline phase were also investigated in terms of Hirshfeld surfaces. In the crystal lattice, a three-dimensional hydrogen-bonded network is observed, including formation of a two-dimensional molecular scaffolding motif. Hirshfeld surfaces and fingerprint plots of three co-crystals show that structures are stabilized by H⋯H, N–H⋯O, H⋯Br and C⋯H intermolecular interactions. Besides, the studies of the solubility showed that this co-crystal strategy could promote the solubility of AMB and follow the order: co-crystal 1 2 3 .

A tapered silicon nanowire array (TSiNWs)/poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) hybrid solar cell was obtained based on alkali treatment processing. TSiNWs are engineered by combining electroless etching and an alkali solution in which the morphology of the tapered nanowire can be controlled by changing the immersing time. The results show that the alkali treatment could taper the silicon nanowires so that the polymer could conformally infiltrate into SiNWs via spin-coating. The experimental results demonstrate that the length and morphology of the SiNWs are key factors for improving the cell performance. Compared to the SiNWs/polymer hybird device, the TSiNWs/polymer hybrid solar cell can achieve a high power conversion efficiency of 6.87% and short-circuit current density of 26.7 mA cm−2. Therefore, tapered silicon nanowires are promising structures for realizing economically viable hybrid solar cells based on a very simple, scalable, and low-cost solution route.

A facile, rapid and solvent-free method for the conversion of acids and dihalomethane to the corresponding methylene diesters (acylals) using microwave as activators or assistor, is reported. This method is particularly powerful for the diesterification of carboxylic acids, which afford methylene diesters in good to excellent yields (up to >99%). When the intermediate is trapped, a “double successive S N 2 reactions” mechanism is proved.