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Highly porous nanostructures can be applied in multifunctional sensing devices and energy storage devices. However, an ultrathin nano-porous one dimensional nanowire is rarely reported until now. Herein, an improved solvothermal strategy is adopted to yield ultrathin W 18 O 49 nanowires composed of nano-pores. The resulting W 18 O 49 nanowires exhibited a high specific surface area of 153.2 m2/g, even exceeding the highest value for the tungsten oxide nanowires reported previously. To show the capability of the nano-porous nanowire products, the nanowires were assembled to thin membranes and characterized with three different sensing capabilities, i.e., UV, humidity and pH. Typically achieved response time of the nanowire membrane devices for UV and humidity are 0.2 s and 0.6–1 s, respectively. pH is detected with a high linear characteristic in the range of 3–6. With their one dimensional geometry, nano-porous structure and high sensitivity, the W 18 O 49 nanowires hold tremendous prospect for multifunctional sensing platform. • Highly porous W 18 O 49 nanowires were synthesized via a solvothermal process. • By using nanocellulose, the nanowires could be generated in larger yield. • The nanowires' UV, humidity and pH detection ability were investigated. [ABSTRACT FROM AUTHOR]

Recently, electrospinning has been widely applied to prepare phase-change material fibres. However, the practical applications of electrospinning are limited by its low productivity and potential safety hazards. Herein, a simple centrifugal spinning without the drawbacks of electrospinning was applied to fabricate polyethylene glycol-based PCM fibres with nano-SiC as a highly conductive filler, polyacrylonitrile as the supporting material, and N,N-dimethylformamide as the solvent to dissolve the polymers. Results demonstrate that the PCM fibres were formed by physical combination rather than chemical reaction. The shapes of the PCM fibres remained stable during the phase-change process. Based on differential scanning calorimetry, PAN/PEG/SiC PCM fibres containing 4.0 wt% nano-SiC melted at 51.31 °C with a phase-change latent heat of 69.91 J/g. The thermal conductivity of PAN/PEG/SiC PCM fibres was improved by 79% compared to that of PAN/PEG PCM fibres. The good thermophysical properties of the prepared PAN/PEG/SiC PCM fibres show promise for long-term utilization. Image 1 • The PAN/PEG/SiC PCM fibres were prepared by centrifugal spinning. • The polyacrylonitrile (PAN) was satisfactory PEG supporting matrix. • The relationship of highly conductive filler (nano-SiC) and thermal conductivity was deep investigated. [ABSTRACT FROM AUTHOR]

Centrifugal spinning has recently attracted attention as a safer and more efficient method for preparing polymer micro- and nano-fibres. Our research demonstrates the successful preparation of polystyrene (PS) flexible thermal insulation materials by innovatively spinning PS into fibres. The morphology and size of the fibres were characterised by scanning electron microscopy (SEM). The average diameter of PS fibres decreased from 3.76 μm to 1.31 μm after the addition of nano-SiO 2. The hydrophobicity and contact angle of PS/SiO 2 composite fibres with water was measured by video water contact angle measuring instrument to be 141°. The results demonstrated that the PS/SiO 2 composite fibres were completely stable at or below 300 °C and had a moisture content less than 0.26%. Based on the properties of the fibres, PS/SiO 2 composite fibres have the potential to become a new type of building insulation materials. SEM of PS fibres in different magnification. Image 1046 • Polystyrene (PS) fibres with small diameters and uniform shapes were successfully prepared. • The average diameter of PS/SiO 2 fibres achieved 1.31 μm when 14 wt% nano-SiO 2 added. • The PS/SiO 2 fibres had a very low moisture content below 0.26%. • The PS/SiO 2 composite fibres were completely stable at or below 300 °C. [ABSTRACT FROM AUTHOR]

Following publication of the original article [1], the authors reported errors in Figures 2, 3 and Figure 3 'continued'. [ABSTRACT FROM AUTHOR]

• A computational work regarding how edge activators affect the skin permeation behavior of transfersomes. • A hydrophilic channel model of the skin was established. • Edge activators reduce the deformation energy of transfersomes. • The membrane properties of transfersomes could be altered by edge activators. Transfersomes (TRS) can provide sustained drug delivery and themselves are biocompatible, biodegradable and nontoxic. Edge activators (EAs) are key factors for increasing the deformability of TRS, and this active deformation mechanism is of commercial interest, especially at the molecular level. Accordingly, in this paper, the deformability of pure dipalmitoyl phosphatidylcholine (DPPC) vesicles, TRS with sodium cholate as an EA, and DPPC vesicles containing pogostone (POG) were compared via umbrella sampling technology. The DPPC conformation and membrane fluidity of these three types of bilayer systems were evaluated, and the changes in the membrane properties of vesicles caused by EAs were studied. EAs could increase the deformability of TRS by decreasing the deformation energy barrier due to their amphiphilic structures, which was similar to those of DPPC molecules. The membrane properties also changed via treatment with EAs including altering the tail chain angle, disturbing the ordered tail chain arrangement and prompting lateral diffusion of DPPC molecules. In addition, the impact of EAs on DPPC bilayers was further demonstrated to be concentration dependent. An ideal concentration was identified for the lowest amount of EA that offered a gel-liquid-crystalline phase transition of DPPC bilayers. Importantly, POG, a lipophobic transdermal drug, can also affect the skin permeation behavior of vesicles but had weaker effects than EA. [ABSTRACT FROM AUTHOR]

Rare earth aluminate phosphors are well-known for being nontoxic and environmentally friendly. In this work, Tb3+-doped SrLaAlO 4 phosphors were synthesized via a facile high temperature solid-state reaction method. The Optimum reaction temperature is determined to be 1300 °C based on the results of powder X-ray diffraction (XRD). The SEM patterns and TEM images correspond with the results of Rietveld refinement and show that the SrLa 1-x AlO 4 :xTb3+ samples present a flaky structure. The results of photoluminescence spectrums (PL) show that SrLa 1-x AlO 4 :xTb3+ phosphors can absorb in the UV–vis spectral region of 228 nm–263 nm and exhibit several emission peaks between 450 and 650 nm, and the highest peak was at 508 nm. The luminescence properties of SrLa 1-x AlO 4 :xTb3+ have a strict dependence on the cation substitution levels. When the doping concentration of Tb3+ was 0.05, the emission intensity of the sample is strongest. The thermal quenching result of the SrLa 0.95 AlO 4 :0.05 Tb3+ phosphors shows that these phosphors are relatively sensitive to temperature changes under an excitation of 228 nm, as the temperature increases from 25 °C to 125 °C, the emission intensity (peak at 548 nm) decayed to 55.11% of that at room temperature. However, when the temperature increases to 125 °C, the emission intensity (peak at 548 nm) decayed to 61.16% of the initial value under an excitation of 263 nm, which showed a relatively good thermal stability. The internal quantum efficiency (QE) values of the SrLa 0.95 AlO 4 :0.05 Tb3+ phosphors was measured and determined to be 48%. Under excitations of 228 nm and 263 nm, the lifetimes of the optimized sample SrLa 0.95 AlO 4 :0.05 Tb3+ were 1.3986 ms and 1.2095 ms, respectively, and the CIE coordinates of the sample were calculated as (0.2971, 0.4981), (0.3056, 0.5329), respectively. Under both excitations SrLa 0.95 AlO 4 :0.05 Tb3+ exhibited high-color-purity green emission. • The5D 4.→7F J (J = 6, 5, 4, 3) transitions and 5D 3 →7F J (J = 6, 5, 4) transitions of Tb3+ under UV excitation. • Dexter's theory to explain concentration quenching effect. • The fluorescence decay behavior of the SrLaAlO 4 : Tb3+ phosphor. • The research of the thermal quenching of the SrLaAlO 4 : Tb3+ phosphor. • Distribution of element in SrLaAlO 4 : Tb3+ phosphor investigated by TEM mapping. [ABSTRACT FROM AUTHOR]

Background: Melanoma is one of the most aggressive cancers with extremely poor prognosis, and the median survival time for stage IV patients is approximately 6 to 8 months. Unlike cutaneous melanoma, mucosal melanoma is a rare melanoma subtype among Caucasian patients but its incidence remains as high as 22.6% among Chinese patients. Screening specific genetic variations is the guideline to select targeted drugs for the treatment of advanced melanoma, whereas the genetic variation spectrum and potential therapeutic targets for mucosal melanoma are largely unclear. It is urgent to identify promising genetic variants for mucosal melanoma so as to develop effective targeted therapies for this disease.Methods: Tumor samples from 213 Chinese mucosal melanoma patients were involved in this study. P16INK4a/Cyclin D1/CDK4 copy number was examined using the QuantiGene Plex DNA assay and the correlation between abnormal copy number and clinicopathological parameters was analyzed. Patient-derived xenograft models (PDX) were performed to detect the effects of CDK4/6 inhibitors on the proliferation of mucosal melanoma cells with altered copy number of CDK4 pathway (CDK4, Cyclin D1 and P16INK4a). The molecular mechanisms of CDK4/6 inhibitors on the proliferation of mucosal melanoma were analyzed by RNAseq.Results: Among the 213 samples, the amplification rate of CDK4 and CCND1 was 47.0% and 27.7%, respectively, and the deletion rate of P16INK4a was 57.7%. Patients with more than one genetic abnormality were up to 81.7%. CDK4 pathway gene copy number variation was not associated with the prognosis of patients with mucosal melanoma (P > 0.05). Drug sensitivity tests showed that AT7519, a broad-spectrum CDK inhibitor, and PD0332991, a specific CDK4/6 inhibitor, exhibited higher inhibitory effect on CDK4 signaling pathway abnormal mucosal melanoma cells-derived PDX tumors growth than CDK4 signaling pathway normal ones. RNA-seq analysis showed that CDK4 inhibitors may affect tumor proliferation through multiple signaling pathways.Conclusions: Abnormal copy number of cell cycle related genes is frequently found in mucosal melanoma. CDK4/6 inhibitors significantly suppress the PDX tumor growth with abnormal CDK4 pathway. CDK4 signaling variations predict the effectiveness of CDK4 inhibitors in mucosal melanoma. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation of pollutants is one of the cleanest technologies for environmental remediation. Herein, we prepared NiO/NiTiO3 heterostructure nanofiber (200 nm) films by electrospinning and high temperature heat treatment, using nickel acetate and tetrabutyltitanate as nickel and titanium sources, respectively. The NiO/NiTiO3 heterostructure has advantages of good photodegradation rate constant and stability. By controlling the temperature, we can optimize the phase composition of these nanofibers for better photocatalytic performance. Based on our findings of the Rhodamine B degradation results, the best performance was obtained with 10% NiO and 90% NiTiO3; 92.9% of the Rhodamine B (5 mg/L) was degraded after reaction under full spectrum irradiation for 60 min. More importantly, the repeating test showed that these nanofiber films can remain active and stable after multiple cycles. The mechanisms of the photocatalysis reactions were also discussed. This demonstration provides a guideline in designing a new photocatalyst that we hope will serve the environmental needs for this and the coming century. [ABSTRACT FROM AUTHOR]

The development of white-light-emitting diodes (w-LEDs) makes it meaningful to develop novel high-performance phosphors excited by blue light. Herein, BiOCl:Pr3+ green-yellow phosphors were prepared via a high-temperature solid-state reaction method. The crystal structure, luminescent properties, lifetime, thermal quenching behavior, and quantum yield were studied in detail. The BiOCl:Pr3+ phosphors presented several emission peaks located in green and red regions, under excitation at 453 nm. The CIE coordinates could be tuned along with the changed doping concentration with fair luminescence efficiency. The results also indicated that the optimized doping concentration of Pr3+ ions was at x = 0.0075 because of the concentration quenching behavior resulting from an intense exchange effect. When the temperature reached 150 °C, the intensity of the emission peak at 495 nm could remain at 78% of that at room temperature. The activation energy of 0.20 eV also confirmed that the BiOCl:Pr3+ phosphor exhibited good thermal stability. All these results indicate that the prepared products have potential to be used as a high-performance green-yellow-light-emitting phosphor for blue-light-based w-LEDs. [ABSTRACT FROM AUTHOR]

Ultra-long, single crystal, α-Si3N4 nanowires sheathed with amorphous silicon oxide were synthesised by an improved, simplified solid-liquid-solid (SLS) method at 1150 °C without using flowing gases (N2, CH4, Ar, NH3, etc.). Phases, chemical composition, and structural characterisation using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM/HRTEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) showed that the nanowires had Si3N4@SiOx core-shell structures. The growth of the nanowires was governed by the solid-liquid-solid (SLS) mechanism. The room temperature photoluminescence (PL) and cathodoluminescence (CL) spectra showed that the optical properties of the α-Si3N4 nanowires can be changed along with the excitation wavelength or the excitation light source. This work can be useful, not only for simplifying the design and synthesis of Si-related nanostructures, but also for developing new generation nanodevices with changeable photoelectronic properties. [ABSTRACT FROM AUTHOR]

Radial mesoporous silica (RMS) sphere was tailor-made for further applications in producing shape-stabilized composite phase change materials (ss-CPCMs) through a facile self-assembly process using CTAB as the main template and TEOS as SiO2 precursor. Novel ss-CPCMs composed of polyethylene glycol (PEG) and RMS were prepared through vacuum impregnating method. Various techniques were employed to characterize the structural and thermal properties of the ss-CPCMs. The DSC results indicated that the PEG/RMS ss-CPCM was a promising candidate for building thermal energy storage applications due to its large latent heat, suitable phase change temperature, good thermal reliability, as well as the excellent chemical compatibility and thermal stability. Importantly, the possible formation mechanisms of both RMS sphere and PEG/RMS composite have also been proposed. The results also indicated that the properties of the PEG/RMS ss-CPCMs are influenced by the adsorption limitation of the PEG molecule from RMS sphere with mesoporous structure and the effect of RMS, as the impurities, on the perfect crystallization of PEG. [ABSTRACT FROM AUTHOR]

The large-scale synthesis of Si3N4 nanobelts from quartz and graphite on a graphite-felt substrate was successfully achieved by catalyst-assisted carbothermal reduction-nitridation. The phase composition, morphology, and microstructure of Si3N4 nanobelts were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, energy-dispersive spectroscopy, transmission electron microscopy, and high-resolution transmission electron microscopy. The Si3N4 nanobelts were ~4-5 mm long and ~60 nm thick and exhibited smooth surfaces and flexible shapes. The Si3N4 nanobelts were well crystallized and grow along the [101] direction. The growth is dominated by the combined mechanisms of vapor-liquid-solid base growth and vapor-solid tip growth. The Fe(NO3)3 played a crucial role in promoting the nanobelt formation in the initial stage. The room-temperature photoluminescence spectrum of Si3N4 nanobelts consists of three emission peaks centered at 413, 437, and 462 nm, indicating potential applications in optoelectronic nanodevices. [ABSTRACT FROM AUTHOR]

Task graph scheduling on multiprocessor systems is a representative multiprocessor scheduling problem. A solution to this problem consists of the mapping of tasks to processors and the scheduling of tasks on each processor. Optimal solution can be obtained by exploring the entire design space of all possible mapping and scheduling choices. Since the problem is NP-hard, scalability becomes the main concern in solving the problem optimally. In this paper, a SAT-based optimization framework is proposed to address this problem, in which SAT solver is enhanced by integrating with a scheduling analysis tool in a branch and bound manner to prune the solution space efficiently. Performance evaluation results show that our technique has average performance improvement in more than an order of magnitude compared to state-of-the-art techniques. We further build a cycle-accurate network-on-chip simulator based on SystemC to verify the effectiveness of the proposed technique on realistic multiprocessor systems. [ABSTRACT FROM AUTHOR]