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Lithium-sulfur batteries possess the merits of low cost and high theoretical energy density but suffer from the shuttle effect of lithium polysulfides and slow redox kinetics of sulfur. Herein, novel Co0.85Se nanoparticles embedded in nitrogen-doped carbon nanosheet arrays (Co0.85Se/NC) were constructed on carbon cloth as the self-supported host for a sulfur cathode using a facile fabrication strategy. The interconnected porous carbon-based structure of the Co0.85Se/NC could facilitate the rapid electron and ion transfer kinetics. The embedded Co0.85Se nanoparticles can effectively capture and catalyze lithium polysulfides, thus accelerating the redox kinetics and stabilizing sulfur cathodes. Therefore, the Co0.85Se/NC-S cathode could maintain a stable cycle performance for 400 cycles at 1C and deliver a high discharge specific capacity of 1361, 1001, and 810 mAh g-1 at current densities of 0.1, 1, and 3C, respectively. This work provides an efficient design strategy for high-performance lithium-sulfur batteries with high energy densities.

As a key factor for fast-charging lithium-ion batteries (LIBs), high-rate anode materials that can recharge in a few minutes have aroused increasing attention. However, high-rate performance is always accompanied by low theoretical capacities, such as the widely known high-rate electrode of Li4Ti5O12 (175 mA h g−1), which severely limits its large-scale implementation in the development of high power density LIBs. Here, we report a modified close-spaced thermal evaporation process to deposit 3D-structured Sb2Se3 films (3D-SSF) with tunable morphology as an additive-free anode for LIBs. After a high-rate activation process, 3D-SSF exhibits a flatter discharge plateau than the reported results and could deliver a high capacity of 471 mA h g−1 at an ultrahigh current density of 21 440 mA g−1, which is superior to the widely known high-rate Li4Ti5O12 anode (over 150 mA h g−1 at 8750 mA g−1). Moreover, we reveal a current-regulated Li-ion storage mechanism where 3D-SFF undergoes a synergistic conversion and alloying reaction at low current densities, while an alloying reaction-dominated process at high rates. Beyond that, full batteries with excellent rate performance were successfully assembled by pairing with homemade LiFePO4 (LFP) as the cathode.

Lithium is deemed as the anticipated anode for the next-generation energy storage system. Nevertheless, its commercial application is greatly hindered by the uneven deposition and volume expansion ...

Direct nitrogen photofixation is a feasible solution toward sustainable production of ammonia under mild conditions. However, the generation of active sites for solar-dirven nitrogen fixation not only limits the fundamental understanding of the relationship among light absorption, charge transfer, and catalytic efficiency but also influences the photocatalytic activity. Herein, we report two-dimensional boron-doped niobic acid nanosheets with oxygen vacancies (B-Vo-HNbO3 NSs) for efficient N2 photofixation in the absence of any scavengers and cocatalysts. Impressively, B-Vo-HNbO3 NS as a model catalyst achieves the enhanced ammonia evolution rate of 170 μmol gcat-1 h-1 in pure water under visible-light irradiation. The doublet coupling representing 15NH4+ in an isotopic labeling experiment and in situ infrared spectra confirm the reliable ammonia generation. The experimental analysis and density functional theory (DFT) calculations indicate that the strong synergy of boron dopant and oxygen vacancy regulates band structure of niobic acid, facilitates photogenerated charge transfer, reduces free energy barriers, accelerates reaction kinetics, and promotes the high rates of ammonia evolution. This work provides a general strategy to design active photocatalysts toward solar N2 conversion.

Progressive liver fibrosis, caused by chronic viral infection and metabolic disorders, results in the development of cirrhosis and hepatocellular carcinoma. However, no antifibrotic therapies have been approved to date. In our previous study, adeno‑associated virus (AAV) short hairpin RNAs (shRNAs) targeting hepatitis B virus (HBV) and transforming growth factor (TGF)‑β administration could persistently inhibit HBV replication and concomitantly prevent liver fibrosis. However, the differentially expressed proteins and critical regulatory networks of AAV‑shRNA treatment remain unclear. Accordingly, in the present study, we aimed to analyze differentially expressed proteins in the liver of AAV‑shRNA‑treated mice with HBV infection and liver fibrosis using isobaric tags for relative and absolute quantitation (iTRAQ)‑based quantitative proteomics and to elucidate the underlying antifibrotic mechanisms. In total 2,743 proteins were recognized by iTRAQ‑based quantitative proteomics analysis. Gene Ontology analysis revealed that the differentially expressed proteins mostly participated in peptide metabolism in the biological process category, cytosolic ribosomes in the cell component category, and structural constituents of ribosomes in the molecular function category. Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated that oxidative stress and the peroxisome proliferator‑activated receptor (PPAR) signaling pathway were activated after treatment. Verification studies revealed that AAV‑shRNAs inhibited hepatic stellate cell activation and inflammation by suppressing nuclear factor‑κB p65 phosphorylation and α‑smooth muscle actin expression via upregulation of PPAR‑γ. Hepatocytes steatosis was also decreased by activating the PPAR signaling pathway and improving lipid metabolism. The expression level of TGF‑β was decreased due to upregulation of PPAR‑γ expression and direct inhibition using AAV‑shRNA targeting TGF‑β. TGF‑β‑induced oxidative stress was suppressed by increasing glutathione S‑transferase Pi 1 and reducing peroxiredoxin 1. Collectively, the present results indicated that AAV‑shRNAs were effective in modulating liver fibrosis by reducing oxidative stress, inflammation and activating the PPAR signaling pathway.

Cyclin-dependent kinases (CDKs) are serine/threonine kinases whose catalytic activities are regulated by interactions with cyclins and CDK inhibitors (CKIs). CDKs are key regulatory enzymes involved in cell proliferation through regulating cell-cycle checkpoints and transcriptional events in response to extracellular and intracellular signals. Not surprisingly, the dysregulation of CDKs is a hallmark of cancers, and inhibition of specific members is considered an attractive target in cancer therapy. In breast cancer (BC), dual CDK4/6 inhibitors, palbociclib, ribociclib, and abemaciclib, combined with other agents, were approved by the Food and Drug Administration (FDA) recently for the treatment of hormone receptor positive (HR+) advanced or metastatic breast cancer (A/MBC), as well as other sub-types of breast cancer. Furthermore, ongoing studies identified more selective CDK inhibitors as promising clinical targets. In this review, we focus on the roles of CDKs in driving cell-cycle progression, cell-cycle checkpoints, and transcriptional regulation, a highlight of dysregulated CDK activation in BC. We also discuss the most relevant CDK inhibitors currently in clinical BC trials, with special emphasis on CDK4/6 inhibitors used for the treatment of estrogen receptor-positive (ER+)/human epidermal growth factor 2-negative (HER2−) M/ABC patients, as well as more emerging precise therapeutic strategies, such as combination therapies and microRNA (miRNA) therapy.

The practical application of lithium (Li) metal anode has been greatly hampered by irregular growth of Li dendrites and the volume expansion during the cycle. Constructing a three-dimensional lithiophilic porous framework is regarded as an effective solution. Here, using a CuO nanocluster arrays–decorated carbon fiber cloth (CuO-NC@CFC) to prestore Li via molten infusion has been testified to effectively resolve these bottlenecks. Impressively, after a violent melt-infusion process, the constructed nanostructures can be maintained and transformed into Cu/Li 2O nanocluster arrays, together with highly conductive carbon fiber cloth, provide fast charge transport during Li stripping/plating process. As demonstrated by finite element simulations and experimental evidence, the formed Cu/Li2O nanocluster arrays not only redistribute Li+ flux and reduce local current density but also serve as Li nucleation sites. Consequently, the as-acquired Li/Cu-NC@CFC electrodes could significantly buffer volume fluctuation and regulate Li deposition behavior, exhibiting an ultrastable and ultralong lifespan (400 h at 5 mA/cm2 with 1 mAh/cm2 Li and 800 h at 5 mA/cm2 with 5 mAh/cm2 Li in symmetric cells). When coupled with LiFePO4, the Li/Cu-NC@CFC electrode could deliver a high capacity of 110.3 mAh/g after 500 cycles at 2 C.

A novel, simple and rapid method based on magnetic effervescent tablet-assisted ionic liquid dispersive liquid-liquid microextraction (MEA-IL-DLLME) followed by graphite furnace atomic absorption spectrometry (GFAAS) determination was established for the speciation of selenium in various food and beverage samples. In the procedure, a special magnetic effervescent tablet containing CO2 sources (sodium carbonate and sodium dihydrogenphosphate), ionic liquids and Fe3O4 magnetic nanoparticles (MNPs) was used to combine extractant dispersion and magnetic recovery procedures into a single step. The parameters influencing the microextraction efficiency, such as pH of the sample solution, volume of ionic liquid, amount of MNPs, concentration of the chelating agent, salt effect and matrix effect were investigated and optimised. Under the optimised conditions, the limits of detection (LODs) for Se(IV) were 0.021 μg l(-)(1) and the linear dynamic range was 0.05-5.0 μg l(-)(1). The relative standard deviation for seven replicate measurements of 1.0 μg l(-)(1) of Se(IV) was 2.9%. The accuracy of the developed method was evaluated by analysis of the standard reference materials (GBW10016 tea, GBW10017 milk powder, GBW10043 Liaoning rice, GBW10046 Henan wheat, GBW10048 celery). The proposed method was successfully applied to food and beverage samples including black tea, milk powder, mushroom, soybean, bamboo shoots, energy drink, bottled water, carbonated drink and mineral water for the speciation of Se(IV) and Se(VI) with satisfactory relative recoveries (92.0-108.1%).