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Using first-principles calculations, we show that the band gap and electron effective mass (EEM) of graphene/boron nitride heterobilayers (C/BN HBLs) can be modulated effectively by tuning the interlayer spacing and stacking arrangement. The HBLs have smaller EEM than that of graphene bilayers (GBLs), and thus higher carrier mobility. For specific stacking patterns, the nearly linear band dispersion relation of graphene monolayer can be preserved in the HBLs accompanied by a small band-gap opening. The tunable band gap and high carrier mobility of these C/BN HBLs are promising for building high-performance nanodevices.

We have carried out first-principles calculations to explore the energetics and dynamics of Li in graphyne, a novel carbon allotrope consisting of spÀsp 2 hybridized carbon atoms, relevant for anode lithium intercalation in rechargeable Li-ion batteries. In contrast to graphite where Li diffusion is confined in the interlayer space (in-plane diffusion), the unique atomic arrangement and electronic structures enable both inplane and out-plane diffusion of Li ions in graphyne with moderate barriers, 0.53À0.57 eV. The highest Li intercalation density in graphyne can be LiC 4 , exceeding the up limit of LiC 6 in the commonly used graphite. The high lithium mobility and high storage capacity make graphyne a promising candidate for the anode material in battery applications.

Non-coding RNAs (ncRNAs) are considered major players in physiological and pathological processes based on their versatile regulatory roles in different diseases including cardiovascular disease. Circular RNAs (circRNAs), a newly discovered class of RNAs, constitute a substantial fraction of the mammalian transcriptome and are abundantly expressed in the cardiovascular system. However, the regulatory functions of these circRNAs in ischemic cardiac disease remain largely unknown. Here, we investigated the role of a circRNA transcribed from the sodium/calcium exchanger 1 (ncx1) gene, named circNCX1, in oxidative stress-induced cardiomyocyte apoptosis during ischemic myocardial injury.Methods: Divergent polymerase chain reaction (PCR) was conducted to amplify the circRNA. The circular structure of circNCX1 was verified by Sanger sequencing and RNase R digestion. The subcellular localization of circNCX1 was detected by fluorescence in situ hybridization (FISH). To test the expression pattern and function of circNCX1 during oxidative stress, H9c2 cells and neonatal rat cardiomyocytes were treated with H2O2 or hypoxia-reoxygenation (H/R). Mechanistically, the interaction of circNCX1 with miRNA was examined by AGO2-IP and RNA pull-down assays. The regulatory role of circNCX1 in target gene expression was tested by western blot and luciferase reporter assays. At the animal level, we constructed a myocardial ischemia-reperfusion (I/R) mouse model to analyze the effect of circNCX1 on heart function, cardiomyocyte apoptosis and cardiac remodeling.Results: circNCX1 was increased in response to reactive oxygen species (ROS) and promotes cardiomyocyte apoptosis by acting as an endogenous miR-133a-3p sponge. Due to competitive binding of circNCX1 to miR-133a-3p, the suppressive activity of pro-apoptotic gene cell death-inducing protein (CDIP1) by miR-133a-3p was reduced. Knockdown of circNCX1 in murine cardiomyocytes and heart tissues reduced the levels of CDIP1 and attenuated the apoptosis and I/R injury.Conclusions: Our findings reveal a novel regulatory pathway that comprises circNCX1, miR-133a-3p and CDIP1, that is involved in cardiomyocyte apoptosis. This pathway may serve as a potential therapeutic avenue for ischemic heart diseases.

BackgroundCelastrol is an active ingredient of Chinese medicine Tripterygium wilfordii which is clinically used to treat the immune diseases. Currently, celastrol is documented as a potent agent for treating cancer and inflammatory disorders. This study was to investigate the effect of celastrol on cisplatin nephrotoxicity and the underlying mechanism.MethodsMale C57BL/6 mice were treated with cisplatin (20 mg/kg) with or without celastrol treatment (1 and 2 mg/kg/day). In vitro, human proximal tubule epithelial cell line (HK−2) and mouse renal tubule epithelial cells (RTECs) were treated with cisplatin (5 μg/mL) with or without celastrol administration. Then renal injury and cell damage were evaluated.FindingsIn vivo, after celastrol treatment, cisplatin-induced kidney injury was significantly ameliorated as shown by the improvement of renal function (BUN, serum creatinine, and cystatin C), kidney morphology (PAS staining) and oxidative stress (MDA) and the suppression of renal tubular injury markers of KIM-1 and NGAL. Meanwhile, the renal apoptosis and inflammation induced by cisplatin were also strikingly attenuated in celastrol-treated mice. In vitro, celastrol treatment markedly inhibited cisplatin-induced renal tubular cell apoptosis, suppressed NF-κB activation, and improved mitochondrial function evidenced by the restored mtDNA copy number, mitochondrial membrane potential, and OXPHOS activity in cisplatin-treated renal tubular epithelial cells.InterpretationThis work suggested that celastrol could protect against cisplatin-induced acute kidney injury possibly through suppressing NF-κB and improving mitochondrial function.FundThe National Natural Science Foundation of China, National Key Research and Development Program, and Natural Science Foundation of Jiangsu Province.

Planar heterojunction perovskite solar cells with a high efficiency up to 17.76% are fabricated by modifying the compact TiO2 (c-TiO2) with a [6,6]-phenyl-C61-butyric acid (PCBA) monolayer. High quality CH3NH3PbI3 films can be easily fabricated on PCBA-modified c-TiO2 substrates by a one-step solution processing method. Significant improvements of the device parameters are observed after PCBA modification. A high open-circuit voltage (Voc) of 1.16 V has been achieved, indicating that the PCBA monolayer can act as a hole blocking layer to reduce the trap site density atop the c-TiO2 and the hole recombination at the c-TiO2 /perovskite interface. The enhancement of the fill factor, as well as the partial quenching of the fluorescence of perovskite after modification with PCBA, reveals that the charge extraction is improved.

Dry powder inhalers (DPIs) offer distinct advantages as a means of pulmonary drug delivery and have attracted much attention in the field of pharmaceutical science. DPIs commonly contain micronized drug particles which, because of their cohesiveness and strong propensity to aggregate, have poor aerosolization performance. Thus carriers with a larger particle size are added to address this problem. However, the performance of DPIs is profoundly influenced by the physical properties of the carrier, particularly their particle size, morphology/shape and surface roughness. Because these factors are interdependent, it is difficult to completely understand how they individually influence DPI performance. The purpose of this review is to summarize and illuminate how these factors affect drug–carrier interaction and influence the performance of DPIs.

Four small molecular acceptors (SM1-4) comprising a central benzene core, two thiophene bridges and two 1,8-naphthalimide (NI) terminal groups were designed and synthesized by direct C-H activation. SM1 has a planar chemical structure and forms H-aggregation as films. By attachment of different substituents on the central benzene ring, the dihedral angles between the two NI end groups of SM1-4 gradually increased, leading to a gradual decrease of planarity. SM1-4 all possess a high-lying LUMO level, matching with wide band gap (WBG) polymer donors which usually have a high-lying LUMO level. When used in OSCs, devices based on SM1 and WBG donor PCDTBT-C12 gave higher electron mobility, superior film morphology and better photovoltaic performance. After optimization, a PCE of 2.78% with a V(oc) of 1.04 V was achieved for SM1 based devices, which is among the highest PCEs with a V(oc) higher than 1 V. Our results have demonstrated that NI based planar small molecules are potential acceptors for WBG polymer based OSCs.