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Background: Inflammation is one of the causes of neuroblastoma progression. Propofol attenuates inflammation by repressing nuclear transcription factor κB (NF-κB) in different diseases. But its effect on oxygen-glucose deprivation/reoxygenation (OGD/R)-induced inflammation is not known. Objective: This study investigated the role and mechanism of action of propofol on OGD/Rinduced inflammation in mouse N2A neuroblastoma cells. Methods: MTT was performed on mouse neuroblastoma cells N2A to assess and select the maximum safe dose of propofol. Next, N2A cells were pretreated with propofol and then, exposed to the OGD condition for 3 h and reoxygenated for 6 h. The content of the inflammatory factors, interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α), in the medium was measured by ELISA, while their protein expression was detected by western blot and immunofluorescence. The protein expression of P65, p-P65, IKBα and p-IKBα belonging to the NF-κB pathway was also determined by western blot in N2A cells. To further confirm the mechanism of propofol on OGD/R-induced inflammation in mouse N2A cells, P65 was over-expressed and the above experiments were repeated. Results: Propofol did not affect cell viability of N2A cells even at the maximum concentration used (30 µM), thus, 30 µM of propofol was selected to perform our experiments. Besides, OGD/R induced inflammation and activation of NF-κB pathway with increased p-P65 and p-IKBα expression, and propofol pretreatment inhibited OGD/R induced inflammation and activation of NF-κB pathway in N2A cells. Over-expression of P56 abolished the effects of propofol on OGD/Rinduced inflammation and activation of NF-κB pathway in N2A cells. Conclusion: Our work demonstrated for the first time that propofol pretreatment ameliorated OGD/R induced inflammation via NF-κB pathway modulation in mouse neuroblastoma N2A cells, indicating that propofol might be considered as a potential therapeutic approach to reduce inflammation in neuroblastoma.

In this paper, the temperature of butane flame is measured by Thin Filament Pyrometer(TFP). The luminous length of butane flame is about 80mm. The high temperature resistant material tungsten-rhenium wire is placed into the flame, the diameter of tungsten-rhenium wire is 0.1mm, 0.25mm, 0.5mm.A scientific sCMOS camera calibrated by emissivity calibration experiment was used to measure the radiance of tungsten-rhenium filament, and Planck's blackbody radiation law was used to calculate the temperature of the filament., so as to get the temperature of the butane flame. The results show that the highest temperature of the butane flame measured by the filament pyrometer is 1122K.Standard armored K-type thermocouple is used to verify the experimental accuracy, and the measurement error between the calculated value and the standard value is less than 5%. The experimental results of butane combustion show that this method can be applied to similar temperature measurement.

Cerium oxide has constantly attracted intense attention during the past decade both in research and industry as an appealing catalyst or a noninert support for catalysts, for instance, in the water-gas shift reaction and hydrogenation of the ketone group. Herein, the cerium oxide surface has been chosen to investigate the adsorption and decomposition behaviors of the N,N′-bis(1-ethylpropyl)-perylene-3,4,9,10-tetracarboxdiimide (EP-PTCDI) molecule by photoelectron spectroscopy. As expected, EP-PTCDI molecules self-assemble on the cerium oxide surface comprising both trivalent and tetravalent cerium at room temperature. Interestingly, the EP-PTCDI molecule exhibits selective adsorption on cerium oxide after the heating treatment. It was found that the ketone group of EP-PTCDI first undergoes hydrogenation after annealing to 400 °C, which is probably related to the fact that high temperature annealing provides sufficient thermal energy to trigger the reaction between the ketone group and trivalent cerium. Furthermore, EP-PTCDI molecules are discovered to start to decompose hierarchically on the ceria substrate from annealing at 400 °C due to the strong molecule–substrate interaction and the effective catalysis by the trivalent cerium, whereas the decomposition sequence of functional groups is revealed to be, first, the ethyl propyl group (−C5H9), followed by the hydrogenated ketone (alcohols) group. Finally, our study may provide a new platform for the fundamental understanding of complex organic reactions on the cerium oxide surface.

Topological insulators (TIs) have become one of the intensely pursed topics during the past few years due to their robust gapless edge states, among which bismuth (Bi) enjoys a good reputation beca...

Fundamental understanding of the bonding motifs that elaborately mediate the formation of supramolecular nanostructures is essential for the rational design of stable artificial organic architectures. Herein, the structural transformation of the adsorption complex of 2, 7-dibromopyrene (Br2 Py) on the Au(111) surface has been investigated by scanning tunnelling microscopy combined with X-ray photoemission spectroscopy and density function theory calculations. In the initial stage of self-assembly, well ordered patterns are formed in the manner of extended supramolecular structures balanced by intermolecular halogen bonding motifs, whilst the Au(111) reconstruction is still fairly visible. Subsequent thermal annealing promotes the dehalogenation and on-surface Ullmann coupling, and polymerized oligomers are consequently constructed. Interestingly, such polymerized chains are still stably mediated by the halogen bonding motif via dissociated Br atoms which are revealed to be absorbed on the bridge site of Au(111), while the number of halogen bonds increases significantly from self-assembly to Ullmann coupling polymerization, indicating that the halogen bonding motif contributes significantly to the extended one-dimensional polymers.

Mo-48.2% Ag films were fabricated by direct current (DC) magnetron sputtering and annealed in an argon atmosphere. The effects of annealing on the surface morphology, resistivity and surface-enhanced Raman scattering (SERS) performance of Mo-48.2% Ag films were investigated. Results show a mass of polyhedral Ag particles grown on the annealed Mo-48.2% Ag films&rsquo, surface, which are different from that of as-deposited Mo-Ag film. Moreover, the thickness and the resistivity of Mo-48.2% Ag films gradually decrease as the annealing temperature increases. Furthermore, finite-difference time-domain (FDTD) simulations proved that the re-deposition Ag layer increases the &ldquo, hot spots&rdquo, between adjacent Ag nanoparticles, thereby greatly enhancing the local electromagnetic (EM) field. The Ag layer/annealed Mo-48.2% Ag films can identify crystal violet (CV) with concentration lower than 5 &times, 10&minus, 10 M (1 mol/L = 1 M), which indicated that this novel type of particles/films can be applied as ultrasensitive SERS substrates.

The emergence of transition metal dichalcogenides (TMD) as an exciting class of materials with appealing potentials in electronic and optoelectronics has drawn intensive attention in the past few years. Herein, we report the fabrication of NiSe2, which has been predicted to be a promising candidate in the field of electrocatalyst, by direct selenylation of the nickel substrate after epitaxial growth of selenium on a nickel foil. With a combination of photoelectron spectroscopy (PES), X-ray diffraction (XRD), scanning electron microscopy (SEM) and density function theory (DFT) calculations, it is possible to identify the phase transition among the previously reported stable Ni-Se phases and the ultimate formation of NiSe2 species by external annealing at varying temperatures. While SEM reveals the morphology of NiSe2 film with flat terraces, XRD, XPS and DFT calculations demonstrate that NiSe2 is the relatively stable phase formed on the Ni substrate from the cohesive energy point of view. Furthermore, valence band spectra point out the nonmetallic level of these different Ni-Se compounds, agreeing well with literature reports. In the end, our report may indicate a feasible approach to synthesize the pure NiSe2 species under solution-free condition and an encouraging step forward towards non-noble electrocatalysts.

Mo-Cu alloy films with different thicknesses were deposited on flexible polyimide substrates by magnetron sputtering and, optionally, in situ vacuum annealing. Compositions and surface morphologies of the films were characterized by FESEM and EDS. And this revealed annealing had an important effect on the microstructure of the alloy films. During annealing, a large number of uniformly distributed copper (Cu) particles formed spontaneously on the Mo-Cu alloy films surface, with their sizes, shapes and number closely related to Cu content, annealing temperature, and film thicknesses. Thus, we demonstrated a new way for preparing Cu/Mo-Cu alloy film with large specific surface area which can be used as surface-enhanced Raman scattering (SERS) substrate.

The optoelectronic properties of perovskite films are closely related to their quality. Herein, we report the doping of guanidinium iodide (C(NH 2 ) 3 I) organic into CH 3 NH 3 PbI 3 perovskite thin films and reveal the enhancement of both morphology and structure of the perovskite films by doping with C(NH 2 ) 3 I in the range of 0 to 25%. Nuclear magnetic resonance is utilized to determine the molecular structure of the synthesized C(NH 2 ) 3 I and grazing-incidence X-ray diffraction is employed to characterize the lattice structure of doped perovskite films. Furthermore, doped CH 3 NH 3 PbI 3 perovskite films with different amounts of C(NH 2 ) 3 I is also investigated by X-ray photoelectron spectroscopy and scanning electron microscopy. It is found that the C(NH 2 ) 3 I dopant mainly assembles on the surface region of the pristine CH 3 NH 3 PbI 3 perovskite film. In the end, 5% C(NH 2 ) 3 I to CH 3 NH 3 PbI 3 perovskite film is found to be the doping ratio resulting in the best film structure and surface morphology.

The structural stability is crucially important for thermoelectric material from the point view of energy harvesting applications. Herein, p-type Zn-Sb semiconductor doped with magnesium (Mg 0.04 Zn 3.96 Sb 3 ) was experimentally investigated after thermal cycles to verify its structure stability, via a combination of synchrotron-based X-ray absorption spectroscopy (XAFS), grazing-incidence X-ray diffraction (GI-XRD), scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). While no visible structure change was discovered from XRD measurement after annealed to 573 K in air, well-preserved atomic structure of Mg-doped Zn-Sb was also demonstrated by XAFS. Interestingly, SEM indicated significantly improved surface morphology whilst EDS clearly showed the relative steadiness of each element's spatial distribution on surface. On basis of these findings, it was concluded in the end that the doping of magnesium substantially improves the thermal stability of zinc-antimonite compounds, and the possible mechanism underneath was also demonstrated.

The interfacial electronic structures of cobalt phthalocyanine adsorbed on a semimetal Bi(111) surface have been systematically investigated herein. Our study first indicates that the CoPc molecule is quite sensitive to the adsorption site on the relatively inert Bi(111) surface. Secondly, apparent change of the electronic structures of CoPc has been revealed upon adsorption as compared to that in the gas phase, due to the orbital coupling between the cobalt partial empty state and the surface state from the bismuth substrate and interfacial charge transfer. Interestingly, the local magnetic moment is still retained for the adsorbed CoPc molecule on the diamagnetic Bi(111) surface, which is different to that on other noble metal substrates. Analysis of the charge density difference and the Bader charge provides evident insight on the mechanism of interfacial charge transfer which is chiefly mediated by the central Co atom and the weak vdW dispersion between the π-conjugated macrocyclic ligand and the bismuth substrate, as further confirmed by experimental XPS results. In the end, our report may provide an appealing route towards the fundamental understanding and reliable engineering of interfacial interactions between magnetic and semimetal nanostructures.

Mo-Ag films with different thicknesses were deposited on flexible polyimide (PI) substrate by DC magnetron sputtering. The phase, surface morphology, composition and thickness of the Mo-Ag films were characterized by XRD, FESEM, EDS and TEM, respectively. The most outstanding result indicates that many monodisperse single crystal Ag nanoparticles are spontaneously formed on the surface of the deposited Mo-Ag films at room temperature. The Ag nanoparticles/Mo-37.5% Ag film has rich active “hot spots”, which can be used as an effective surface-enhanced Raman scatting (SERS) substrate by covering a thin layer of silver on the surface, and the detection limit of Rhodamine 6G solution can reach 10-12 mol/L. The Ag nanoparticles/Mo-Ag films prepared at room temperature provided a new idea for the preparation of novel particle films and high-sensitivity flexible SERS substrates.

Autophagy regulates the metabolism, survival and function of numerous types of cell, including cells that comprise the cardiovascular system. The dysfunction of autophagy has been demonstrated in atherosclerosis, restenotic lesions and hypertensive vessels. As a member of the Ras GTPase superfamily, Rab7 serves a significant role in the regulation of autophagy. The present study evaluated how Rab7 affects the proliferation and invasion, and phenotypic transformations of aortic dissection (AD) smooth muscle cells (SMCs) via autophagy. Rab7 was overexpressed in AD tissues and the percentage of synthetic human aortic SMCs (HASMCs) was higher in AD tissues compared with NAD tissues. Downregulation of Rab7 decreased cell growth, reduced the number of invasive cells and decreased the percentage cells in the G1 phase. Autophagy of HASMCs was inhibited following Rab7 knockdown. Inhibition of autophagy with 3‑methyladenine or Rab7 knockdown suppressed the phenotypic conversion of contractile to synthetic HASMCs. The action of Rab7 may be mediated by inhibiting the Ras/Raf/mitogen‑activated protein kinase (MAPK) kinase (MEK)/extracellular signal related kinase (ERK) signaling pathway. In conclusion, the results revealed that Rab7‑mediated autophagy regulated the behavior of SMCs and the phenotypic transformations in AD via activation of the Ras/Raf/MEK/ERK signaling pathway. The findings of the present study may improve understanding of the role Rab7 in the molecular etiology of AD and suggests the application of Rab7 as a novel therapeutic target in the treatment of human AD.

Self-assembly of functional molecules on solid substrate has been recognized as an appealing approach for the fabrication of diverse nanostructures for nanoelectronics. Herein, we investigate the growth of cobalt phthalocyanine (CoPc) on a Bi(111) surface with focus on the interface electronic structures utilizing photoelectron spectroscopy. While charge transfer from bismuth substrate to the molecule results in the emergence of an interface component in the Co 3p core level at lower binding energy, core-levels associated to the molecular ligand (C 1s and N 1s) are less influenced by the adsorption. In addition, density functional theory (DFT) calculations also support the empirical inference that the molecule-substrate interaction mainly involves the out-of-plane empty Co 3d orbital and bismuth states. Finally, valence band spectra demonstrate the molecule-substrate interaction is induced by interface charge transfer, agreeing well with core level measurements. Charge transfer is shown to be mainly from the underlying bismuth substrate to the empty states located at the central Co atom in the CoPc molecules. This report may provide a fundamental basis to the on-surface engineering of interfaces for molecular devices and spintronics.