Constraints on modified Chaplygin gas from recent observations and a comparison of its status with other models

In this Letter, a modified Chaplygin gas (MCG) model of unifying dark energy and dark matter with the exotic equation of state $p_{MCG}=B\rho_{MCG} -\frac A{\rho_{MCG}^\alpha}$ is constrained from recently observed data: the 182 Gold SNe Ia, the 3-year WMAP and the SDSS baryon acoustic peak. It is shown that the best fit value of the three parameters ($B$,$B_{s}$,$\alpha$) in MCG model are (-0.085,0.822,1.724). Furthermore, we find the best fit $w(z)$ crosses -1 in the past and the present best fit value $w(0)=-1.114<-1$, and the $1\sigma$ confidence level of $w(0)$ is $-0.946\leq w(0)\leq-1.282$. Finally, we find that the MCG model has the smallest $\chi^{2}_{min}$ value in all eight given models. According to the Alaike Information Criterion (AIC) of model selection, we conclude that recent observational data support the MCG model as well as other popular models.Comment: 8 pages, 1 figur

An enhanced gas ionization sensor from Y-doped vertically aligned conductive ZnO nanorods

A stable and highly sensitive gas ionization sensor (GIS) constructed from vertically aligned, conductive yttrium–doped ZnO nanorod (YZO NR) arrays is demonstrated. The conductive YZO NRs are synthesized using a facile one-pot hydrothermal method. At higher Y/Zn molar ratio, the aspect ratio of the YZO NRs is increased from 11 to 25. Doping with yttrium atoms decreases the electrical resistivity of ZnO NRs more than 100 fold. GIS measurements reveal a 6-fold enhancement in the sensitivity accompanied with a significant reduction in breakdown voltage from the highly conductive YZO NRs. Direct correlations between the resistivity of the NRs and GIS characteristics are established

A Fracture Analysis of Ti-10Mo-8V-1Fe-3.5Al Alloy Screws during Assembly

Titanium screws have properties that make them ideal for applications that require both a high strength-to-weight ratio and corrosion resistance, such as fastener applications for aviation and aerospace. The fracture behavior of Ti-10Mo-8V-1Fe-3.5Al (TB3) alloy screws during assembly was explored. Besides visual examination, other experimental techniques used for the investigation are as follows: (1) fracture characteristics and damage morphology via scanning electron microscopy (SEM); (2) chemical constituents via energy dispersive spectroscopy (EDS) and hydrogen concentration testing; (3) metallographic observation; (4) stress durability embrittlement testing; and (5) torsion simulation testing. Results show that the fracture mode of the screws is brittle. There is no obvious relation to hydrogen-induced brittle. The main reason for the fracture of titanium alloy screws is internal defects, around which oxygen content is high, increasing brittleness. The internal defects of screws result from grain boundary cracking caused by hot forging

Zearalenone Degradation by Dielectric Barrier Discharge Cold Plasma: The Kinetics and Mechanism

In this study, dielectric barrier discharge (DBD) cold plasma was used to degrade zearalenone and the efficiency of degradation were evaluated. In addition, the degradation kinetics and possible pathway of degradation were investigated. The results showed that zearalenone degradation percentage increased with increasing voltage and time. When it was treated at 50 KV for 120 s, the degradation percentage could reach 98.28%. Kinetics analysis showed that the degradation process followed a first-order reaction, which fitted the exponential function model best (R&sup2; = 0.987). Meanwhile, liquid chromatographywith quadrupole time-of-flight mass spectrometry (Q-TOF LC/MS) was used to analyze the degradation products, one major compound was identified. In this study, the reactive species generated in cold plasma was analyzed by Optical Emission Spectroscopy (OES) and the free radicals were detected by Electron Spin Resonance (ESR). This study could provide a theoretical basis for the degradation of zearalenone to a certain extent

1D to 2D Growth of NaF Crystals in Photothermo-Refractive Glasses

International audienceThe precipitation of NaF crystals with a low refractive index only in the UV exposure region is essential to obtain high refractive index change in photothermo-refractive (PTR) glass for producing high-performance volume Bragg gratings (VBGs). However, the precision control of the growth of NaF crystals in the UV exposure region of PTR glass remains challenging. In this work, the effect of Al2O3 on the crystallization behavior of NaF crystals in PTR glass was investigated using the nonisothermal crystallization kinetic method. After photothermal-induced nucleation, the crystallization activation energy (Ea) of PTR glass decreased first and then increased with the rise in the Al2O3 content. The appropriate amount of Al2O3 (4 mol %) is helpful for reducing the Ea and promoting the formation of NaF crystals. The crystal growth index (n) and crystal growth dimension (m) suggest that the crystallization behavior of NaF crystals was photothermally induced nucleation and crystallization of 1D growth. The increasing trend of the m values indicates that the crystals tend to transit from 1D to 2D growth with the increase in Al2O3 content. When Al2O3 is 6 mol %, n equals m + 1, which implies the NaF crystals crystallize spontaneously rather than growing on the Ag nuclei. The crystals observed using scanning electron microscopy images showed that irregular precursors appeared first and then grew into needle-like crystals. When the NaF crystals grew sufficiently long, they transformed into lamellar crystals. This work elucidates the crystallization process of NaF crystals in PTR glass and provides guidance for the production of high-performance VBGs

High Verdet constant of Tb2O3-doped 2 O 3-doped TiO-B2O3-Al2O3-Na2O 2 O 3-Al 2 O 3-Na 2 O magneto-optical glass

International audienceTb-doped magneto-optical (MO) glass is widely used in fiber optics, optical isolators, and modulators. However, only the paramagnetic Tb3+ 3 + ions exhibit significant MO effects, whereas the diamagnetism Tb4+ 4 + ions suppress the MO effects. Therefore, the valence state control of Tb ions is very critical to optimize MO performance. Here, a reduction strategy was introduced to adjust the Tb valence in glass to achieve the high MO effect. The TiO, which has low valence Ti2+ 2 + ions and good reducibility, was used to suppress the oxidation of Tb3+ 3 + to Tb4+ 4 + ions. In the TiO-B2O3-Al2O3-Na2O 2 O 3-Al 2 O 3-Na 2 O glass, 10 mol% TiO can increase the Verdet constant at 650 nm by 19%. With the further increase in Tb2O3 2 O 3 concentration, the Verdet constant reaches a high value of 117 rad/(T&lt;middle dot&gt;m) &lt;middle dot&gt; m) at 650 nm, which is close to the Verdet constant of TGG crystal (121 rad/(T&lt;middle dot&gt;m)). &lt;middle dot&gt; m)). This work provides a new approach to increase the Verdet constant of MO glass

Circular RNA circ0001955 promotes cervical cancer tumorigenesis and metastasis via the miR-188-3p/NCAPG2 axis

Abstract Background Circular RNAs (circRNAs) are known to play a crucial role in a variety of malignancies. However, the precise role of circRNAs in cervical squamous cell carcinoma (CSCC) remains largely unknown. Methods The expression of circ0001955 was determined by real-time quantitative PCR and fluorescence in situ hybridization. To examine the effects of circ0001955 on CSCC metastasis and growth, functional experiments were conducted in vitro and in vivo. Mechanistically, nucleocytoplasmic separation, dual luciferase reporter assay, RNA antisense purification experiments, and rescue experiments were performed to confirm the interaction between circ0001955, miR-188-3p, and NCAPG2 in CSCC. Results Here, we demonstrated that a circRNA derived from the CSNK1G1 gene (circ0001955) is significantly upregulated in CSCC. The overexpression of circ0001955 promotes tumor proliferation and metastasis, whereas the knockdown of circ0001955 exerts the opposite effects. Mechanistically, circ0001955 competitively binds miR-188-3p and prevents miR-188-3p from reducing the levels of NCAPG2, activating the AKT/mTOR signaling pathway to induce epithelial mesenchymal transformation. Notably, the application of an inhibitor of mTOR significantly antagonized circ0001955-mediated CSCC tumorigenesis. Conclusion circ0001955 promotes CSCC tumorigenesis and metastasis via the miR-188-3p/NCAPG2 axis which would provide an opportunity to search new therapeutic targets for CSCC. Graphical Abstrac

Supplementary document for High Verdet Constant of Tb₂O₃-doped TiO-B₂O₃-Al₂O₃-Na₂O Magneto-Optical Glass - 6955363.pdf

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