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Many studies have reported that circular RNAs play a vital role in the malignant progression of human cancers. However, the role and underlying mechanism of circRNAs in the development of gliomas have not been fully clarified. In this study, we found that circ_0001367 was downregulated in glioma tissues and showed a close correlation with glioma patient survival. Functional assays demonstrated that upregulation of circ_0001367 could suppress the proliferation, migration and invasion of glioma cells in vitro and inhibit glioma growth in vivo. Furthermore, bioinformatics analysis, luciferase reporter assay and RNA immunoprecipitation assay indicated that circ_0001367 can serve as a sponge for miR-431 and that miR-431 acts as an oncogene by regulating neurexin 3 (NRXN3). In addition, rescue experiments verified that circ_0001367 could regulate both the expression and function of NRXN3 in a miR-431-dependent manner. In conclusion, circ_0001367 functions as an suppressor in glioma by targeting the miR-431/NRXN3 axis and may be a promising therapeutic target against gliomas.

Citrinin (CIT)—an established public health threat—is a frequent component of red fermented rice (RFR). Although various quantitative techniques have been developed to detect citrinin in red fermen...

Acquired chemoresistance is a major limiting factor in the clinical treatment of glioblastoma (GBM). However, the mechanism by which GBM acquires therapeutic resistance remains unclear. Here, we aimed to investigate whether METTL3-mediated N6-methyladenosine (m6A) modification contributes to the temozolomide (TMZ) resistance in GBM. We demonstrated that METTL3 METTL3-mediated m6A modification were significantly elevated in TMZ-resistant GBM cells. Functionally, METTL3 overexpression impaired the TMZ-sensitivity of GBM cells. In contrast, METTL3 silencing or DAA-mediated total methylation inhibition improved the sensitivity of TMZ-resistant GBM cells to TMZ in vitro and in vivo. Furthermore, we found that two critical DNA repair genes (MGMT and APNG) were m6A-modified by METTL3, whereas inhibited by METTL3 silencing or DAA-mediated total methylation inhibition, which is crucial for METTL3-improved TMZ resistance in GBM cells. Collectively, METTL3 acts as a critical promoter of TMZ resistance in glioma and extends the current understanding of m6A related signaling, thereby providing new insights into the field of glioma treatment.

A multilayer (Ni/Al/Ni) catalyst design is proposed to synthesize high-density carbon nanotubes (CNTs) on a conductive titanium silicide substrate. The Al intermediate layer immobilizes the Ni catalyst on the substrate during nanoparticle formation by interacting with the top and bottom Ni catalyst film, suppressing the diffusion of Ni into silicide and sintering of the Ni nanoparticles, as evidenced by secondary ion mass spectroscopy and atomic force microscopy analysis. Owing to the stable, high-density and evenly distributed nanoparticle catalysts with the multilayer catalyst design, we have synthesized vertically aligned CNTs with a density of 2.0 × 1010/cm2 and an average 50 walls per CNT. The CNT density using the Ni/Al/Ni catalyst is three times higher than that with the pure Ni catalyst. Furthermore, the proposed catalyst design enables CNT synthesis at a temperatures as low as 350 °C. The synthesized CNTs show Ohmic contact with Ti silicide, suggesting the catalyst design is promising for CNT applications on conductive substrates, especially for interconnect applications.

The poor utilization of visible light and the speedy recombination of photoexcited carriers limit the further development of carbon nitride polymer (CN) photocatalysts. It is a valid means for enhancing the photocatalytic ability to ameliorate the electronic and physicochemical properties via modifying the structure of CN. The sulfur- and chlorine-codoped graphite CN (S/Cl-CN) was successfully fabricated with low-cost ammonium chloride and thiourea as precursors. The introduction of Cl atoms will establish interlayer channels to promote interlayer charge migration and up-shifted conduction-band level. S atom is appropriate to be incorporated into the CN framework to replace N atom, which is beneficial to adjust the band gap. Then, inorganic-organic CdSe-diethylenetriamine (D) grown in situ are employed to fabricate a S/Cl-CN/CdSe-D heterojunction. S/Cl-CN/CdSe-D heterojunction exhibits greater hydrogen evolution activity compared to CN, S-CN, Cl-CN, S/Cl-CN, CdSe-D and CN/CdSe-D. Finally, Step-scheme (S-scheme) photocatalytic mechanism based on S/Cl-CN/CdSe-D heterostructure was proposed.

Carbon Nanotubes (CNTs) with wall density of 5.3×1012cm-2 are synthesized on NiSi at 450°C by using Ti barrier layer and multilayer Ni/Al/Ni catalyst. Based on this synthesis process, sub-micron CNT vias are fabricated, with via resistance of 47 Ωμm2. Resistance trend of scaling CNT via is presented to shows prospect of CNT vias for advanced technology node.

Highly dispersible LaF3:x% Tb3+ (x = 1, 3, 5, 8, 10) nanoparticles capped with citrate ligands have been prepared and functionalized by salicylate and 5-sulfosalicylate, respectively. The structure, morphology, photoluminescence properties, fluorescence dynamics and ligand sensitization mechanism have been studied systemically. Monitoring the characteristic emission of the Tb3+ 5D4–7F5 transition, the broad absorption bands in the UV domain are obtained with the functionalized nanoparticles. Under excitation of the π–π* electron transition absorption of salicylate (or 5-sulfosalicylate), the enhanced luminescence of Tb3+ ions is achieved in the functionalized nanoparticles. The ligand sensitization is potentially interpreted by a dipole–dipole sensitization mechanism. The luminescence lifetimes of Tb3+ ions in the nanoparticles functionalized by aromatic carboxylate acids are longer than the ones in LaF3:Tb3+ nanoparticles capped with citrate ligands.

This paper describes the potential of using carbon nanotube (CNT) as a via-filling material to enhance the performance mainstream CMOS technology. Due to the CMOS compatibility constraint, the choice of catalyst material and processing conditions have been significantly limited. After a careful selection process, Ni is found to be a workable material. Through catalyst engineering, we have demonstrated that it is possible to form CNT filled vias on metal or silicide substrate at low temperature with low contact resistance. The impact of via dimensions and processing condition has also been studied. Based on statistical analysis using measured data, the best-case projected via resistance for a 30nm via is 295Ω, which is within one order of magnitude of its copper and tungsten counterparts.

In this paper, NaYF 4 nanocrystals and NH 4 Y 3 F 10 sub-microcrystals were prepared using a polyol method. After being annealed, NH 4 Y 3 F 10 can convert into YF 3 , which is a very efficient host matrix for upconversion. The structures of obtained NaYF 4 , NH 4 Y 3 F 10 and YF 3 samples are pure cubic phase, a mixture of cubic and hexagonal phase and pure orthorhombic phase, respectively. The size of obtained NaYF 4 nanocrystals is about 20 nm, and those of NH 4 Y 3 F 10 and YF 3 sub-microcrystals are both about 200 nm. When co-doped with Er 3+ and Yb 3+ , NaYF 4 and YF 3 samples can emit bright light under 978 nm excitation. Upconversion mechanisms in Yb 3+ /Er 3+ co-doped NaYF 4 and YF 3 samples were discussed.

One-dimensional nanosized phosphors demonstrate special structural and photoluminescence properties, which have application potential in some optical fields. In this article, we present our recent progress on preparation and luminescence properties of some one-dimensional rare earth compounds and complexes, the core–shell oxide nanowires prepared by a two-step hydrothermal route, the nanowires of some inorganic compounds doped with rare earths and rare earth complexes/PVP composites prepared by the electrospinning method, and the rare earth complexes in the SBA-15 mesoporous molecule sieves. In these systems, some novel or improved photoluminescence properties are observed such as improved luminescence quantum yield, thermal stability and/or photostability, and depressed thermal effect in upconversion luminescence.

Observation of nighttime nitrate radical (NO3) was performed by using long path differential optical absorption spectroscopy (LP-DOAS), on the outskirts of Hefei, China. The time series of NO3 and supporting parameters were simultaneously measured for a week (31 May–7 June 2006). The results indicated that the average concentration of NO3 was 15.6 pptv with an average lifetimes of 96 s, whereas, NO3 production rates varied from 8 × 105/(cm3·s) to 2.98 × 107/(cm3·s). Furthermore, the calculated N2O5concentration averaged at 380 pptv. Analysis of data indicated that direct sinks were probably dominating the NO3 loss process during this campaign. The results were compared with other campaigns in the boundary layer.

In this work, the luminescence properties of samarium ions-doped titanium dioxide prepared by the sol–gel process were studied. A strong orange red emission (4G5/2−6H7/2 (orange) and 4G5/2–6H9/2 (red)) ascribed to the electron transitions in 4f5 configuration of Sm3+ ions was observed upon excitation into TiO2 host. The energy transfer from TiO2 to Sm3+ was verified and the relevant mechanism was discussed. In addition, the impacts of metal ion codopants upon the TiO2:Sm3+ luminescence properties were studied. The results indicated that the central excitation band shifted to blue in the bismuth-codoped materials (0.5–4% in molar ratio), while it shifted to red in the zirconium-codoped materials. Such materials may find applications in white light-emission diode (LED) and tunable solid lasers.

Sub-micrometer-sized fibers of europium-doped yttria (Y 2 O 3 :Eu 3+ ) were prepared by electrospinning followed by high-temperature calcinations for the first time. The fibers were with diameters of 200–400 nm and lengths of several 10 μm and cubic in phase. The spectral properties of the Y 2 O 3 :Eu 3+ fibers were studied, in contrast with those of bulk powders. The results indicated that in the present Y 2 O 3 :Eu 3+ fibers the excited charge transfer band had slightly blue shift in comparison with that in the bulk due to weaker covalence of Eu–O bonds. In addition, both of the lifetimes of the 5 D 1 and 5 D 0 states in the fibers became shorter than that in the bulk due to improved nonradiative transition rates.

Uniform Gd2O3: Eu3+ nanowires were fabricated by using anodic aluminum oxide template (AAO). The spectral measurements indicate that with the increasing annealing temperature the excitation band of Eu3+ in Gd2O3 : Eu3+ nanowires/AAO shifted blue, the intensity ratio of 5D0–7F2 to 5D0–7F1 decreased, and the lifetime became longer. In the sample annealed at 1000°C two spectral components, the sharper and broader lines were identified, corresponding to two different local environments, the Eu3+ ions in cubic phase and in amorphous phase, respectively. The 5D0–7F1 transitions of Eu3+ ions in cubic phase had longer lifetime than that in amorphous phase. In contrast to the lifetime of the 5D0–7FJ transitions in the bulk, that in Gd2O3 : Eu3+/AAO composite films increased due to influence of the surrounding media (AAO).

Atmospheric NO3 can be measured with LP-DOAS. The improved method was developed to give a more accurate fitting of nitrate radical. The measurement errors were reduced to below 7% and detection limits reached 3.8ppt.

Harringtonine (HT), a kind of anticancer drug isolated from Chinese herb Cephalotaxus hainanensis Li, has been used in the clinical treatment of human glanulocytic leukemia and chromic myelocytic leukemia. In this study, we investigated the effect of Bcl-2 on HT-induced apoptosis and Ca2+ mobilization in human leukemia HL-60 cells. 1 μg/ml HT induced the apoptosis of HL-60/Neo cells in a time-dependent manner; while 1 μg/ml HT failed to induce the apoptosis of HL-60/ Bcl-2 cells. HT-, A23187- (a Ca2+ ionophore), Carbonyl cyanide m-chlorophenylhydrazone (CCCP,a specific releaser of Ca2+ from mitochondria) and thapsigargin- (an inhibitor of endoplasmic reticulum Ca2+> -ATPase) induced changes in [Ca2+]i were monitored by using Fluo 3-AM with confocal laser scanning microscopy. The results demonstrated that HL-60 cells with enforced expression of Bcl-2 (HL-60/Bcl-2 cells) had increased Ca2+ permeability and increased intracellular Ca2+ store in comparison with HL-60 cells with negative control vectors (HL-60/Neo cells), suggesting that Bcl-2 might prevent HT-induced apoptosis by increased Ca2+ permeability and increased intracellular Ca2+ buffering capacity.

Carbon nanotube (CNT) filled contact plugs with silicide as the bottom electrode have been demonstrated in this letter. Nickel has been used as the main catalyst to achieve CMOS compatibility. By modifying the catalyst from a pure Ni single layer structure to a Ni/Al/Ni multilayer composite, uniform selective CNT growth on Ti silicide substrate has been achieved. At a low temperature of 450 °C, the vertically aligned CNTs with a density of $1.1\times 10^{11}$ tubes/cm2 inside the silicon dioxide contact plug are formed without the need of catalyst patterning. Four-point Kelvin structures are designed to measure the resistance of the CNT filled contact plugs. Measurement results show that an ohmic contact plug resistance of 216 $\Omega \cdot \mu \text{m}^{2}$ is obtained.

Uniform, ultra-small-sized and well-water-dispersible LaF(3) nanoparticles doped with trivalent rare earth (RE) ions (Eu(3+) or Tb(3+)) have been synthesized by a simple, low temperature synthesis route. The nanoparticles, with sizes of about 3.2 nm (for those doped with Eu(3+)) and 3.0 nm (for those doped with Tb(3+)), are roughly spherical and monodisperse. 1,2,4,5-Benzenetetracarboxylic acid (labeled as BA) as sensitizer has been bonded to the surface of the nanoparticles, which can sensitize the emission of RE(3+) in the LaF(3) nanoparticles. The BA-LaF(3):RE(3+) (RE = Eu or Tb) nanoparticles have a broad absorption band in the UV domain, and show enhanced luminescence of RE(3+) based on an energy transfer from BA ligands to RE(3+) ions (i.e. the so-called "antenna effect"). Due to the dual protection of organic ligands (BA) and inorganic matrices (LaF(3)), BA-LaF(3):RE(3+) (RE = Eu or Tb) nanoparticles have longer excited state lifetimes than LaF(3):RE(3+) (RE = Eu or Tb) nanoparticles as well as lanthanide coordination polymers of BA.

From July 4 to 11, 2006 at Back Garden site (23°28'86”N; 113°02'91”E), nighttime nitrate radical (NO3) was measured with a long path differential optical absorption spectroscopy (DOAS) during an intensive field campaign in the Pearl River Delta of China. The NO3 concentration in polluted air masses varied from 3.6 to 82.5 ppt with an average level of 21.8 ± 1.8 ppt. NO3 at these levels can play a significant role in oxidation of volatile organic compounds (VOCs). The calculated production rate of nitrate radical ranged from 8 × 10^5 to 2.98 × 10^7 cm^(-3) s^(-1), while its lifetimes spanned from between just several seconds to 650 seconds, with an average of 89 seconds. N2O5 levels were calculated with the average of 620 ± 93 ppt during this campaign. The possible scavenging processes for the nitrate radical were obtained by using a statistical analysis of the correlation between NO3 and NO levels, NO3 concentration and its production rate, and the NO3 lifetime and NO2 levels, respectively. Results showed that the direct losses were of importance at Back Garden in summer Pearl River Delta, China.

By using Hoechst 33342, rabbit anti calmodulin antibody, FITC-labeled goat anti rabbit IgG and SR101 (sulfo rhodamine 101) simultaneously to stain individual normal and transformed cells, the microspectrophotometric analysis demonstrated that 3 markers which represented the nucleus, calmodulin and total protein respectively, could be recognized in individualj cells without interference. The phase of the cell cycle was determined by DNA content (Hoechst 33342). We found that in transformed cells (NIH3T3) tsRSV-LA90, cultured at 33°C and transformed C3H10T1/2 cells), the ratio of calmodulin to total protein (based on the phases of cell cycle)was higher than that in normal cells (NIH3T3 tsRSV−LA90 cells, cultured at 39°C and C3H10T1/2 cells)in every cell cycle phase. This ratio increased obviously only from G1 to S phase in either normal or transformed cells. The results showed that calmodulin really increased during the transformation, and its increase was specific. In the meantime when cells proceeded from G1 to S, the intracellular calmodulin content also increased specifically.

To modify the photoluminescence properties the Eu(DBM)3 bath complexes were encapsulated into the sub-nanometer pores of aluminosilicates zeolites L and Yand characterized by X-ray diffraction (XRD), transmission electron micrographs (TEM), Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible (UV-vis) absorption spectra. The luminescent properties of the encapsulated composites (Eu-L and Eu-Y) were systematically studied. The results indicate that in both the two composites the crystal-field symmetry becomes lower, as a consequence, the 5D0-7F2 electronicdipole transition relative to the 5D0-7F1 magnetic-dipole transition of Eu3+ increases in contrast to the pure complexes. The outer quantum efficiency of the Eu3+ emission and the photostability of Eu3+ are both improved considerably. The adsorption of water in the composites has influence on the thermostability and decay dynamics of the Eu3+ emission. In the composite Eu-L, which contains less water the thermostability of luminescence is improved considerably and the lifetime becomes longer in comparison to the pure complexes. Overall, zeolite L is a more ideal host material for modification of lanthanide complexes.

In this paper, YVO4:Eu3+/YBO3:Eu3+ composite was fabricated by chemical corrosion through a two-step hydrothermal process, i.e., first preparation of YBO3:Eu3+ nanocrystals and subsequent chemical corrosion by Na3VO4 solution. A novel energy-transfer and luminescent route via UV and VUV excitation was identified (YBO3 phase→ YVO4 phase → Eu3+ ions in the YVO4 phase), which remained in the sample annealed at high temperature. In this composite high quantum yield was maintained, and considerably improved color purity was induced. A corrosive interface between the YVO4:Eu3+ and YBO3:Eu3+ phases was identified by the site-selective excitation technique, where the local environment surrounding Eu3+ was extremely complex. It is believed that, through further optimization, this novel composite can be candidate phosphors for red PDPs and Hg-free fluorescent lamp in the future.

Ternary terbium complexes were fully encapsulated and uniformly distributed into the channels of unmodified and modified mesoporous molecule sieves of SBA-15 and characterized by transmission electron micrographs (TEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-vis) absorption spectra, inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and elemental analysis. The luminescent properties for the encapsulated complexes were systematically studied in contrast to the pure complexes, including excitation and emission spectra, fluorescence dynamics, photostability under UV exposure, and the temperature dependence of intensity and lifetime. The results indicate that the excitation bands assigned to the pi-pi* electron transition of the ligands for Tb complexes encapsulated in SBA-15 were split into different components due to decreased symmetry and disappeared at long wavelengths. Owing to suppressed vibration transitions, the outer quantum efficiency of the 5D4-7FJ (J = 0-5) emissions was enhanced largely in comparison to the pure complexes. In addition, the photostability and thermostability of the emissions were also improved considerably.

Efficiently luminescent composite fibers of poly (vinyl pyrrolidone) (Mw≈1300000) and europium complex Eu(TTA)3(TPPO)2 (TTA is thenoyltrifluoroacetone; TPPO is triphenylphosphine oxide) were prepared by electrospinning, with average diameters of 200–500nm and lengths of several tens of micrometers. Their photoluminescence properties were studied in comparison to the pure Eu(TTA)3(TPPO)2 complex. It was significant to observe that the thermal stability of photoluminescence in the composite fibers was improved considerably over the pure complex.