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A methodology is presented to characterize the crystallographic texture of atomic configurations on the basis of Euler angles. Texture information characterized by orientation map, orientation distribution function, texture index, pole figure and inverse pole figure is obtained. The paper reports the construction and characterization of the texture of nanocrystalline configurations with different grain numbers, grain sizes and percentages of preferred orientation. The minimum grain number for texture-free configurations is ∼2500. The effect of texture on deducing grain size from simulated X-ray diffraction curves is also explored as an application case of texture analysis. In addition, molecular dynamics simulations are performed on initially texture-free nanocrystalline Ta under shock-wave loading, which shows a 〈001〉 + 〈111〉 double fiber texture after shock-wave compression.

Ferroptosis is a new-found iron-dependent form of non-apoptotic regulated cell death (RCD), which is activated on therapy with several antitumor agents, but the potential mechanism remains unclear. Erastin, exhibiting selectivity for RAS-mutated cancer cells, induces ferroptosis by increasing iron and lipid reactive oxygen species (ROS) levels in cell. Ferroportin (Fpn), the sole iron export protein, participates in the regulation of intracellular iron concentration. In this study, we investigated the role of Fpn on ferroptosis induced by erastin in SH-SY5Y cells.The cell viability was determined by CellTiter 96® AQueous Non-Radioactive Cell Proliferation Assay kit. The activity of caspase-3 was measured by ELISA kit. qRT-PCR was performed to examine the mRNA expression of Fpn. Western blot assay was conducted to examine the expression level of marker proteins. Specific commercial kits were used to examine the levels of MDA, ROS and iron in cells, respectively.Ferroptosis was evaluated by intracellular lipid ROS level and iron concentration. Hepcidin could prevent erastin-induced ferroptosis by degrading Fpn. Erastin (5 μg/mL) was observed to induce ferroptosis in neuroblastoma cells at 6 hours, which was promoted by knockdown of Fpn. The expression of Fpn gene and protein was decreased in SH-SY5Y cells treated with erastin. After treatment with erastin, Fpn siRNA transfection in SH-SY5Y cells was able to accelerate ferroptosis-associated phenotypic changes. Fpn acted as a negative regulator of ferroptosis by reducing intracellular iron concentration. Knockdown of Fpn enhanced anticancer activity of erastin.These results suggested that knockdown of Fpn accelerated erastin-induced ferroptosis by increasing iron-dependent lipid ROS accumulation, highlighting Fpn as a potential therapeutic target site for neuroblastoma. Thus, Fpn inhibitors may provide new access for chemosensitization of neuroblastoma.

To achieve fast flood modelling for urban area, a efficient two-dimensional model based on cellular automata was developed and further coupled with a hydrological model. The model is tested using an analytical and a real event case. The analytical case results show that the model is capable of simulating water-depth process with good agreement with the analytical solution under a reasonable slope threshold and grid resolution. Slope threshold and grid resolution are the two key factors affecting the computational efficiency and model accurcay. In the case of the real event case, the results are also reasonably.In general, this model can be applied to rapid flood analysis in large urban areas.

Transparent conductive gallium-doped zinc oxide (Ga-doped ZnO) films were prepared on glass substrate by magnetron sputtering. The influence of substrate temperature on structural, optoelectrical and surface properties of the films were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), spectrophotometer, four-point probe and goniometry, respectively. Experimental results show that all the films are found to be oriented along the c-axis. The grain size and optical transmittance of the films increase with increasing substrate temperature. The average transmittance in the visible wavelength range is above 83% for all the samples. It is observed that the optoelectrical property is correlated with the film structure. The Ga-doped ZnO film grown at the substrate temperature of 400 °C has the highest figure of merit of 1.25 × 10−2 Ω−1, the lowest resistivity of 1.56 × 10−3 Ω·cm and the highest surface energy of 32.3 mJ/m2.

The aim of this investigation was to determine whether tumour necrosis factor-alpha (TNF-α) has any effect on endothelial progenitor cells (EPCs). Total mononuclear cells were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 days culture, attached cells were stimulated with tumour necrosis factor-α (final concentrations: 0, 10, 20, 50 and 100 mg/l) for 0, 6, 12, 24 and 48 h. EPCs were characterized as adherent cells double positive for DiLDL-uptake and lectin binding, by direct fluorescence staining. EPC proliferation and migration were assayed using the MTT assay and modified Boyden chamber assay, respectively. EPC adhesion assay was performed by re-plating those cells on fibronectin-coated dishes, and adherent cells were counted. Tube formation activity was assayed using a tube formation kit. Levels of apoptosis were revealed using an annexin V apoptosis detection kit. Vascular endothelial growth factor Receptor-1 (VEGF-R1) and stromal derived factor-1 (SDF-1) mRNA, assessed by real-time RT-PCR inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) were assayed by western blot analysis. Incubation of EPCs with tumour necrosis factor-α reduced EPC proliferation, migration, adhesion, tube formation capacity, iNOS and eNOS in concentration- and time-dependent manners. Tumour necrosis factor-α reduced proliferation, migration, adhesion and tube formation capacity of EPCs. TNF-α increased EPC apoptosis level, reduced VEGF-R1 and SDF-1 mRNA expression; tumour necrosis factor-α also reduced iNOS and eNOS in the EPCs.

High quality Co-doped ZnO films with good reproducibility have been prepared under different oxygen partial pressure by radio-frequency magnetron sputtering. These films were characterized using numerous characterization techniques including X-ray diffraction, electrical transport, and magnetization measurements. The effect of oxygen partial pressure on the structural, magnetic, and electrical properties of Co-doped ZnO films has been systematically studied. It was found that the structural, magnetic, and electrical properties of Co-doped ZnO films are dependent on oxygen partial pressure. The saturated magnetization of Co-doped ZnO films rapidly increases with decreasing oxygen partial pressure, whereas the resistivity decreases with decreasing oxygen partial pressure. Our findings indicate that the magnetic and electrical properties of Co-doped ZnO films can be tuned by careful control of oxygen partial pressure. In addition, it was further demonstrated that the oxygen vacancy defect is absolutely necessary to induce ferromagnetic couplings in Co-doped ZnO films.

Surface modification was performed on the indium-tin-oxide (ITO) substrates for organic light-emitting diodes (OLEDs) by oxygen plasma. The effects of oxygen plasma treatment on the surface properties of ITO substrates and its aging were investigated by the measurements of the chemical composition. contact angle and surface energy. We observe that oxygen plasma treatment improves the stoichiometry of the surface and enhances ITO wetting, so as to improve the surface properties of ITO substrates. With the increment of storage time, however, the improved ITO surface properties tend to decay and the surface energy decreases. Furthermore, we studied the effect of aging variation of surface properties of treated ITO substrates on the performance of OLEDs, in terms of driving voltage, luminance, and efficiency. The device performance of the OLEDs was found to become worse with the increasing storage time after oxygen plasma on ITO substrates. The results demonstrate that the device performance of the OLEDs strongly depends on the surface properties of the ITO substrates.

The Pr suppression of the superfluid density in Bi2Sr2Ca1−xPrxCu2O8+δ single crystals is discussed using the zero-temperature in-plane penetration depth extracted from the second peak field in magnetization curves. It is found that the results fit better to the modified dirty d-wave model than the usual model. The relationship between the superfluid density and the critical temperature is also discussed in the underdoped region and one finds that the phase fluctuation model cannot account for the critical temperature in the system, which may be due to the interaction between the thermally excited quasiparticles and the impurity scattering induced quasiparticles.

SynopsisObjective Previous investigations suggested that cherry blossoms could provide valuable bioactive materials. However, few observations regarding the anti-inflammatory effect of cherry blossoms were reported. This study was to explore the anti-inflammatory effect of cherry blossom extract (CBE), which was used as a soothing ingredient in skincare product. Methods In vitro study, the anti-inflammatory effect of CBE on the nitric oxide (NO) inhibition assay in lipopolysaccharide (LPS)-treated RAW 264.7 cells was investigated. In vivo study, 40 volunteers were included in a randomized, single-blinded, placebo-controlled trial. 24-hour-occlusive test chambers were applied on the flexor side of the forearm with 3% sodium lauryl sulphate (SLS). Subsequently, the test areas were treated on 9 subsequent days with a cream containing 3% CBE or a placebo. Evaluation included a visual score and determination of erythema value (E value). Results In vitro study, 2% CBE reduced NO production by 31.83% compared to the placebo. In the SLS irritant patch test, the visual score and erythema value of CBE were lower than that of the placebo on D5 and D9. Conclusion Cherry blossom extract shows good anti-inflammatory effect in vitro and in vivo and represents a promising functional ingredient in soothing skincare product by reducing skin inflammation.

In this work, we coated molybdenum oxide on submicrospheres of amorphous alumina and crystalline alumina, using a sonochemical method. The sonication products were characterized by transmission electron microscopy, x-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, ultraviolet–visible, Raman, Fourier transform infrared spectroscopy, and surface area (Brunauer–Emmett–Teller) measurements. We found that on crystalline alumina, the blue oxide of molybdenum was formed, while on amorphous alumina, the presence of an isolated tetrahedrally coordinated Mo oxide species was confirmed. It seems that the amount and types of surface hydroxyl groups on the surface of alumina play an important role in both the oxidation of Mo and the relative content of Mo species in the sonication product. The surface area of the alumina-coated Mo oxide is about 11 times larger than that of the bare alumina. An explanation for this change is offered.

Isothermal constant-displacement-rate compression tests of superalloy IN718 were conducted using a computer-controlled MTS machine, at temperatures from 960 °C to 1040 °C, initial strain rates from 0.001 to 1.0 s−1, and true strains from 0.105 to 1.204 (corresponding to a relative height reduction from 10 to 70 pct). The flow stress was obtained directly from compression tests using the controlling computer. The grain size was obtained by the intercept method and by comparing microstructures to the ASTM standard grain chart. Based on the results of these tests, a mathematical model showing the hot-deformation behavior of superalloy IN718 was developed in the form of a constitutive equation and a Hall-Petch relationship. Both the flow stress and the grain size calculated from the model were compared to the experimental results. Meanwhile, the effect of hot-deformation parameters such as strain, strain rate, and temperature on the flow stress and on the grain size was analyzed according to the model. It was found that these parameters influenced the flow stress and the grain size. The model developed in this work can be used to explain such effects.

Coating of iron oxides on submicrospheres of alumina was carried out by the sonochemical method. Three kinds of alumina were used, namely, the as-prepared, 700 and 1000 °C heated-alumina. TEM results reveal various coating effects on different heat-treated substrates. The optimum coating is obtained on as-prepared amorphous alumina, in which most of the iron oxide particles are adhered to alumina spheres tightly, while in the sample coated on crystallized alumina heated at 1000 °C, most of the iron oxide particles remain separate from the alumina spheres. The strong interaction between iron oxides and alumina substrate was directly observed by XRD, TEM, and IR and magnetic measurements. Owing to the strong interaction between adhered iron particles and alumina substrate, the complete transformation of γ-Fe2O3 to α-Fe2O3 was retarded to higher than 700 °C; conversely, the presence of haematite can induce the formation of α-Al2O3 at the high temperatures. TEM images clearly show the changes of particle size...

Apurinic/apyrimidinic endonuclease1 (APE1), which has the dual functions of DNA repair and redox regulation, is considered to be a promising potential target in cancer treatment. Microarray and qRT-PCR were used to confirm the change of miRNA followed by analysis with comprehensive bioinformatics-based analysis. Both microarray and qRT-PCR demonstrated that 13 microRNAs (miRNAs) were significantly changed (>2-fold) in APE1 knockdown HOS cells; seven of them (hsa-miR-451, hsa-miR-1290, hsa-miR-765, hsa-miR-483-5p, hsa-miR-513a-5p, hsa-miR-129-5p and hsa-miR-31) were up-regulated and the other six (hsa-miR-29b, hsa-miR-197, has-let-7b, hsa-miR-324-5p, hsa-let-7i and hsa-miR-484) were down-regulated. Furthermore, pathway analysis showed that these miRNAs and their target genes affected by the expression of APE1 were involved in pathways relating to developmental processes, regulation of cellular processes, cell signaling (such as TGF-β, Wnt, MAPK and the p53 signaling pathway) and cancers. There are putative binding sites of NF-κB, p53, HIF-1α, AP-1, PEBP2, ATF, NF-Y, Pax-2,CREB and c-Myb in the promoters of several down regulated miRNAs, indicating that APE1 may regulate miRNAs via transcription factors. Our data suggest that our understanding of the biological functions of APE1 will inevitably expand due to the novel pathways that APE1 uses to regulate gene expression through miRNAs.

The aim of this investigation was to determine whether tumour necrosis factor‐alpha (TNF‐α) has any effect on endothelial progenitor cells (EPCs). Total mononuclear cells were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin‐coated culture dishes. After 7 days culture, attached cells were stimulated with tumour necrosis factor‐α (final concentrations: 0, 10, 20, 50 and 100 mg/l) for 0, 6, 12, 24 and 48 h. EPCs were characterized as adherent cells double positive for DiLDL‐uptake and lectin binding, by direct fluorescence staining. EPC proliferation and migration were assayed using the MTT assay and modified Boyden chamber assay, respectively. EPC adhesion assay was performed by re‐plating those cells on fibronectin‐coated dishes, and adherent cells were counted. Tube formation activity was assayed using a tube formation kit. Levels of apoptosis were revealed using an annexin V apoptosis detection kit. Vascular endothelial growth factor Receptor‐1 (VEGF‐R1) and stromal derived factor‐1 (SDF‐1) mRNA, assessed by real‐time RT‐PCR inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) were assayed by western blot analysis. Incubation of EPCs with tumour necrosis factor‐α reduced EPC proliferation, migration, adhesion, tube formation capacity, iNOS and eNOS in concentration‐ and time‐dependent manners. Tumour necrosis factor‐α reduced proliferation, migration, adhesion and tube formation capacity of EPCs. TNF‐α increased EPC apoptosis level, reduced VEGF‐R1 and SDF‐1 mRNA expression; tumour necrosis factor‐α also reduced iNOS and eNOS in the EPCs.

A series of optical thin films of organic semiconductor materials including tri-(8-hydroxyquinoline) aluminum (AlQ 3 ), bis-(2-methyl-8-quinolinolato)-4-(phenyl-phenolato)-aluminium-(III) (B(AlQ)), and N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)benzidine (NPB) were prepared by the vacuum sublimation technique. The optical properties in the UV-visible region of the thin films were investigated through measurements of optical transmittance and absorbance spectra. The optical band gaps were obtained from direct allowed transitions at room temperature by means of the Tauc plots. The Urbach energy and the slope of Urbach edge were calculated, respectively according to the Urbach-edges method. In addition, the single-layer structure devices of glass/metal/organic layer/metal were fabricated, and electrical resistivity of the materials were evaluated in term of the measured the current-voltage characteristics of the prepared devices.

The organic light emitting devices (OLEDs) with the Al, Mg-Ag and LiF/Al cathodes were fabricated by the vacuum sublimation technique, and the effect of the cathode materials on the electroluminescence (EL) characteristics of OLEDs were investigated in terms of the optical and electrical properties. The experimental data and calculation results demonstrate that the electrical and luminescent performance of OLEDs is strongly dependent on the property of cathode material and the characteristics of the cathode/organic interface. The EL characteristics of device with the LiF/Al cathode is better than those of devices with the Mg-Ag and Al cathodes. The device with LiF/Al cathode exhibits highest EL luminance and efficiency, and smallest turn-on voltage and driving voltage. Such an improvement in the device performance can be attributed to the more efficient electron injection at cathode/organic interface, and the better balanced hole and electron recombination in the light-emitting layer, and the fewer accumulated charges near the organic/organic interface.

We present an analytic expression for the point-function demagnetization tensor of equilateral triangular prism recording media made by nanosphere lithography. This result can be used to calculate the demagnetization field in the prism and may improve the precision in finite element micromagnetic models, especially for complex boundary geometric shapes. The corresponding demagnetization factors are calculated through the expression. The distribution of the demagnetization field is discussed at various aspect ratios with magnetization perpendicular to the triangle plane. It is found that the demagnetization field is enhanced in the vicinity of the surfaces and strongly depends on the aspect ratio.

A new method to improve the morphology and the microstructure of sputtered bismuth‐substituted garnet films for optical storage is discussed. The method employs a high ramp up rate and recurrent annealing as well as quenching in an air environment, which results in smaller grain size, smoother surface, and less void volume in the garnet films than that from a conventional oven annealing. We have discovered that samples prepared with a more recurrent annealing only appeared as a single garnet phase, and the samples with a less recurrent annealing appeared as a garnet phase as well as DyFeO3 phase. We observed the microstructure of the annealed films with scanning electron microscopy (SEM). By applying the new method, the as‐deposited films had been successfully crystallized to the (BiDy)3(FeGa)5O12 garnet phase with the grain size of about 300–400 A. They exhibited excellent magneto‐optical properties with a high coercive force about 1300 Oe and an effective Kerr angle of 1.5°. The crystallization process ...

The conventional charge transport models based on density- and field-dependent mobility, only having a non-Arrhenius temperature dependence, cannot well describe the current–voltage (J–V) characteristics of hole-only devices made from disordered organic semiconductors. In this paper, we study the charge transport in a large variety of organic semiconductors and provide evidence for the availability of our improved mobility model based on both the Arrhenius temperature dependence and the non-Arrhenius temperature dependence. It is validated with experimental data collected from hole-only devices made of different organic materials in a wide range of operating conditions. Furthermore, we calculate and analyze in detail some important electrical properties of the relevant polymers by using a numerical method, adopting the uneven discretization and Newton iteration methods to solve the coupled equations describing the space-charge-limited current. It is shown that the boundary carrier density has a significant effect on the J–V characteristics and that the numerically calculated carrier density is a decreasing function of the distance to the interface.

A new method to improve the structure and the magnetic-optical (MO) properties of sputtered bismuth garnet films for MO storage has been studied. The method employs high temperature ramp-up rate recurrent annealing as well as quenching in air environment. It results in small grain size (43.0 nm to approximately 30.0 nm), smooth surface, and less bubbles in the garnet film than those with conventional annealing. We discovered that the sample with more recurrent annealing only appeared in garnet phase, and its counterpart with fewer recurrent annealing appeared in garnet phase as well as DyFeO3 phase. Meanwhile the Farady angle and the coercivity increase with the recurrent number due to the increase of volume transitional rate of crystal phase in the film. Using this new method, garnet film has been successfully crystallized with a grain size of about 30.0 nm with excellent magnetic and MO properties.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The work reports the effect of a tensile stress on the magnetic domain of FeCoSiB amorphous films. The domain structures of the unstressed and stressed FeCoSiB amorphous films with different tensile strains have been studied by magnetic force microscopy (MFM). With the increase of the tensile stress in the samples, it has been observed that the domain structures transform from irregular domains into parallel strip domains, and magnetic contrasts decrease. The MFM image disappears when the tensile stress is strong enough. A model has been presented to explain the evolution of the domain structures under the tensile stress. The effects of the stress on the domain of the films have been discussed.