ZnO nanorod arrays were fabricated using a hydrothermal method. The nanorods were studied by scanning electron microscopy, photoluminescence (PL), time-resolved PL, X-ray photoelectron spectroscopy, and positron annihilation spectroscopy before and after annealing in different environments and at different temperatures. Annealing atmosphere and temperature had significant effects on the PL spectrum, while in all cases the positron diffusion length and PL decay times were increased. We found that, while the defect emission can be significantly reduced by annealing at 200 degrees C, the rods still have large defect concentrations as confirmed by their low positron diffusion length and short PL decay time constants.

Most tumour cells use aerobic glycolysis (the Warburg effect) to support anabolic growth and evade apoptosis. Intriguingly, the molecular mechanisms that link the Warburg effect with the suppression of apoptosis are not well understood. In this study, using loss-of-function studies in vitro and in vivo, we show that the anti-apoptotic protein poly(ADP-ribose) polymerase (PARP)14 promotes aerobic glycolysis in human hepatocellular carcinoma (HCC) by maintaining low activity of the pyruvate kinase M2 isoform (PKM2), a key regulator of the Warburg effect. Notably, PARP14 is highly expressed in HCC primary tumours and associated with poor patient prognosis. Mechanistically, PARP14 inhibits the pro-apoptotic kinase JNK1, which results in the activation of PKM2 through phosphorylation of Thr365. Moreover, targeting PARP14 enhances the sensitization of HCC cells to anti-HCC agents. Our findings indicate that the PARP14-JNK1-PKM2 regulatory axis is an important determinant for the Warburg effect in tumour cells and provide a mechanistic link between apoptosis and metabolism.

Optical properties of isolated silicon nanocrystals ͑nc-Si͒ with a mean size of ϳ4 nm embedded in a SiO 2 matrix that was synthesized with an ion beam technique have been determined with spectroscopic ellipsometry in the photon energy range of 1.1-5.0 eV. The optical properties of the nc-Si are found to be well described by both the Lorentz oscillator model and the Forouhi-Bloomer ͑FB͒ model. The nc-Si exhibits a significant reduction in the dielectric functions and optical constants and a large blueshift ͑ϳ0.6 eV͒ in the absorption spectrum as compared with bulk crystalline silicon. The band gap of the nc-Si obtained from the FB model is ϳ1.7 eV, showing a large band gap expansion of ϳ0.6 eV relative to the bulk value. The band gap expansion is in very good agreement with the first-principles calculation of the nc-Si optical gap based on quantum confinement.

The role of oral microbiota in head and neck squamous cell carcinoma (HNSCC) is poorly understood. Here we sought to evaluate the association of the bacterial microbiome with host gene methylation and patient outcomes, and to explore its potential as a biomarker for early detection or intervention. Here we performed 16S rRNA gene amplicon sequencing in sixty-eight HNSCC patients across both tissue and oral rinse samples to identify oral bacteria with differential abundance between HNSCC and controls. A subset of thirty-one pairs of HNSCC tumor tissues and the adjacent normal tissues were characterized for host gene methylation profile using bisulfite capture sequencing. We observed significant enrichments of Fusobacterium and Peptostreptococcus in HNSCC tumor tissues when compared to the adjacent normal tissues, and in HNSCC oral rinses when compared to healthy subjects, while ten other bacterial genera were largely depleted. These HNSCC-related bacteria were discriminative for HNSCC and controls with area under the receiver operating curves (AUCs) of 0.84 and 0.86 in tissue and oral rinse samples, respectively. Moreover, Fusobacterium nucleatum abundance in HNSCC cases was strongly associated with non-smokers, lower tumor stage, lower rate of recurrence, and improved disease-specific survival. An integrative analysis identified that enrichment of F. nucleatum was associated with host gene promoter methylation, including hypermethylation of tumor suppressor genes LXN and SMARCA2, for which gene expressions were downregulated in the HNSCC cohort from The Cancer Genome Atlas. In conclusion, we identified a taxonomically defined microbial consortium associated with HNSCC that may have clinical potential regarding biomarkers for early detection or intervention. Host–microbe interactions between F. nucleatum enrichment and clinical outcomes or host gene methylation imply a potential role of F. nucleatum as a pro-inflammatory driver in initiating HNSCC without traditional risk factors, which warrants further investigation for the underlying mechanisms.

Zinc oxide is a very promising material for short‐wavelength light‐emitting devices due to its large band gap and high exciton binding energy. Although great progress has been made in recent years, p‐type doping and control over native defects introduced during or after material growth are still significant problems that hinder the development of efficient ZnO based optoelectronic devices. Here we demonstrate a versatile method for the growth or p‐type or n‐type ZnO nanorods from the same growth solution at temperature as low as 90 °C, where the conductivity type is controlled by the preparation of the seed layer for nanorod growth. The differences in the conductivity type can be attributed to dependency of native defect concentrations and hydrogen incorporation on the seed layer preparation method. Room temperature electroluminescence has been demonstrated from homojunction and heterojunction light emitting diodes containing p‐ZnO nanorods.

Nasopharyngeal carcinoma (NPC) is one of the commonest cancers in Southern China. The carcinogenesis is closely associated with Epstein-Barr virus (EBV) infection. In endemic regions with high incidence of NPC, EBV genome can be detected in virtually all NPC tumor tissues. Over the last decade, circulating cell-free EBV DNA has been developed as a tumor marker for NPC. Plasma EBV DNA analysis using real-time PCR has been shown to be useful for early detection, prognostication and monitoring of treatment response of NPC. In this review, the clinical applications of EBV DNA analysis in the management of NPC would be discussed.

Densely stacked silicon nanocrystal layers embedded in the gate oxide of MOSFETs are synthesized with Si ion implantation into an SiO 2 layer at an implantation energy of 2 keV. In this letter, the memory characteristics of MOSFETs with 7-nm tunnel oxide and 20-nm control oxide at various temperatures have been investigated. A threshold voltage window of ∼ 0.5 V is achieved under write/erase (W/E) voltages of +12 V/−12 V for 1 ms. The devices exhibit good endurance up to 10 5 W/E cycles even at a high operation temperature of 150 • C. They also have good retention characteristics with an extrapolated ten-year memory window of ∼ 0.3 V at 100 • C. Index Terms-Low energy ion beam, memory effect, silicon nanocrystal (nc-Si).

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