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This work is devoted to the studies of optimal perturbation and its transient growth characteristics in Spiral Poiseuille flow (SPF). The Poiseuille number P , representing the dimensionless axial pressure gradient, is varied from 0 to 20,000. The results show that for the axisymmetric case, with the increase of axial shear, the peaks of the amplitudes of azimuthal and radial velocities are both shifted towards the inner cylinder, and a second peak appears near the outer cylinder for both velocity components. Viewing the time evolution of azimuthal shear contribution J V and axial shear contribution J W to the kinetic energy growth of the optimal perturbation, while P is large enough (P = 1 0 , 0 0 0 , 20,000), the Reynolds stress mechanism in the meridional plane (r , z) is dominant for the transient growth behavior in SPF relative to anti-lift-up mechanism, which is dominant in the absence of axial flow for co-rotating Taylor–Couette flow with wide gap. For the oblique mode with azimuthal wave number m = 1 0 , which becomes the optimal azimuthal mode over a wide range of azimuthal wave number (m = 0 –10) when P is large enough, the peaks of the amplitudes of azimuthal and radial velocities are both shifted towards the outer cylinder, opposite to the axisymmetric case. [ABSTRACT FROM AUTHOR]

Glioblastoma is the most common primary brain cancer and it is nearly impossible to remove the entire tumor with surgery or a single drug. EGFRvIII is the most frequent genetic change associated with glioblastoma, so EGFRvIII-based targeting therapies provide promise for treating glioblastoma. Herein, poly[2-methoxy-5-(2′-ethylhexyloxy)-p-phenylenevinylene] (PPV) was used as the core to prepare a conjugated polymer nanoparticle (PPVN) modified with anti-EGFRvIII (PPVN-A) that exhibited high ROS generation ability under white light irradiation. PPVN-A could target EGFRvIII-overexpressed tumor cells and damaged more than 90% of tumor cells with the light illumination while PPVN without modification exhibited no obvious cytotoxicity toward these cells under the same condition. Thus, the photodynamic treatment of glioblastoma cells using PPVN-A could be achieved, indicating the potential of anti-EGFRvIII-modified nanoparticles as a therapeutic material for treating glioblastoma in clinic. [ABSTRACT FROM AUTHOR]

In this study, we present new zircon U-Pb and Hf isotope data and geochemical analyses for Jurassic igneous rocks from the southern Zhangguangcai Range, NE China. In the context of our new U/Pb data together with other published data (n = 165), we recognize three major magmatic pulses in the eastern Songnen Block during the Jurassic: earliest Jurassic (200–195 Ma), late Early Jurassic (183–175 Ma) and early Late Jurassic (ca. 163 Ma). According to the petrological classification scheme, rocks are divided into two categories of andesite and I-type granitoids. Generally, Early Jurassic monzogranites have more evolved compositions with SiO2, Al2O3, and K2O+Na2O concentrations of 67–74 wt.%, 13.28–17.04 wt.% and 7.25–9.31 wt.%, respectively than Late Jurassic granodiorite. Early Jurassic andesite has SiO2, Al2O3, Na2O+K2O contents of 54.64–56 wt.%, 17.27–17.44 wt.% and 3.47–4.06 wt.%, respectively with low Mg# values of 0.18–0.26. In addition, all samples show enrichment in light rare earth elements (LREEs) and large-ion lithophile elements (LILEs) but depletion in high strength field elements (HSFEs, such as Nb, Ta, P and Ti) and low Sr/Y and (La/Yb)N ratios, all of which are characteristic of arc-type magmatic signatures. In view of the Hf isotope signatures, these rocks show high initial 176Hf/177Hf ratios (0.282711–0.283069) corresponding to positive εHf(t) values (+0.39 to +13.66) and Neoproterozoic two-stage model ages (1154–550 Ma). In summary, the geochemical results suggest that the primary magmas of Jurassic granitoids were derived from variable degrees of partial melting of juvenile lower crust, whereas Early Jurassic andesite was derived from the partial melting of mantle wedge peridotite metasomatized by hydrous melts from subducting sediments and/or oceanic crust. The Jurassic arc-type magmatism in the eastern Songnen Block indicates that the Mudanjiang oceanic plate was still subducting in the Jurassic. [ABSTRACT FROM AUTHOR]

DNA groove binders have been poorly studied as compared to the intercalators. A novel Ru(II) complex of [Ru(aeip)2(Haip)](PF6)2 {Haip = 2-(9-anthryl)-1H-imidazo[4,5-f][1,10]phenanthroline and aeip = 2-(anthracen-9-yl)-1-ethyl-imidazo[4,5-f][1, 10]phenanthroline} is synthesized and characterized by elemental analysis, 1H NMR spectroscopy and mass spectrometry. The complex is evidenced to be a calf-thymus DNA groove binder with a large intrinsic binding constant of 106 M−1 order of magnitude as supported by UV–visible absorption spectral titrations, salt effects, DNA competitive binding with ethidium bromide, DNA melting experiment, DNA viscosity measurements and density functional theory calculations. The acid-base properties of the complex studied by UV–Vis spectrophotometric titrations are reported as well. [ABSTRACT FROM AUTHOR]

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Recently, reflectionless or low‐reflection surfaces made of subwavelength structures have been of broad interest in practical engineering. Here, a single‐layer terahertz metasurface is proposed to produce ultralow reflections across a broad‐frequency spectrum and wide incidence angles by controlling the reflection phases of subwavelength structures. To enable full control of the phase range in a continuous band, a combination of two different subwavelength elements are employed, both of which exhibit weak interactions with the incident terahertz waves, thereby showing high local reflectivities near the operating frequency. An optimization method is utilized to determine the array pattern with the minimum overall reflections under the illumination of plane waves. Both numerical simulations and experimental results demonstrate ultralow reflections of terahertz waves by the metasurface over a broad frequency band and wide incidence angles. By using the proposed metasurface, the far‐field scattering patterns of metallic objects can be efficiently controlled, which opens up a new route for low‐reflection surface designs in the terahertz spectrum. [ABSTRACT FROM AUTHOR]

Hydrophobic modification on surface of silicone rubber (SIR) by CF radio frequency inductively coupled plasma is discussed. Static contact angle, atomic force microscopy and X-ray photoelectron spectroscopy were used in characterizing the hydrophobic property, surface appearance and chemical composition of the modified SIR. The results show that the improvement of surface hydrophobic property on modified SIR is attributed to the introduction of fluorocarbon functional groups (C-CF, n = 1, 2, 3) and fluosilicic structures (Si-F and Si-F) during the treatment. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To measure the expression pattern of STAT2 in cervical cancer initiation and progression in tissue sections from patients with cervicitis, dysplasia, and cervical cancer. Methods: Antibody against human STAT2 was confirmed by plasmids transient transfection and Western blot. Immunohistochemistry was used to detect STAT2 expression in the cervical biopsies by using the confirmed antibody against STAT2 as the primary antibody. Results: It was found that the overall rate of positive STAT2 expression in the cervicitis, dysplasia and cervical cancer groups were 38.5%, 69.4% and 76.9%, respectively. The STAT2 levels are significantly increased in premalignant dysplasia and cervical cancer, as compared to cervicitis (P< 0.05). Noticeably, STAT2 signals were mainly found in the cytoplasm, implying that STAT2 was not biologically active. Conclusions: These findings reveal an association between cervical cancer progression and augmented STAT2 expression. In conclusion, STAT2 increase appears to be an early detectable cellular event in cervical cancer development. [Copyright &y& Elsevier]

Three novel amphiphilic 1,10-phenanthroline derivatives, 2-(4'-octadecyloxyphenyl)imidazo[4,5-f]1,10-phenanthroline (5), 2-(3'-methyloxy-4'-octadecyloxyphenyl)imidazo[4,5-f]1,10-phenanthroline (6), and 3-octadecyl-2-(4'-dimethylaminophenyl)imidazo [4,5-f]1,10-phenanthroline (7) were synthesized via a facile, two-step procedure. [ABSTRACT FROM AUTHOR]

A series of organic–inorganic hybrid materials formed by the reaction of (E)-N-butyl-4-(2-(4′-dimethylaminophenyl)ethenyl)pyridinium cations and Dawson heteropolyanions with the stoichiometry of (C19H25N2)7K3[P2Mo4W13MO62] (M=Mn, Co, Ni, Cu and Zn), have been synthesized and characterized by elemental analyses, thermogravimetric and differential thermal analyses, IR spectra, UV-Vis spectra, solid diffuse reflectance UV-Vis-near IR spectra and fluorescence spectra. The results indicate that interaction between the hemicyanine cations and the heteropolyanions exists in the hybrid materials and varies upon changing M from Mn to Zn. The hybrid materials are thermally stable from room temperature to ca. 320 °C. [ABSTRACT FROM AUTHOR]

Background: TEM8 is a cell membrane protein predominantly expressed in tumor endothelium, which serves as a receptor for the protective antigen (PA) of anthrax toxin. However, the physiological ligands for TEM8 remain unknown. Results: Here we identified uPA as an interacting partner of TEM8. Binding of uPA stimulated the phosphorylation of TEM8 and augmented phosphorylation of EGFR and ERK1/2. Finally, TEM8-Fc, a recombinant fusion protein comprising the extracellular domain of human TEM8 linked to the Fc portion of human IgG1, efficiently abrogated the interaction between uPA and TEM8, blocked uPA-induced migration of HepG2 cells in vitro and inhibited the growth and metastasis of human MCF-7 xenografts in vivo. uPA, TEM8 and EGFR overexpression and ERK1/2 phosphorylation were found co-located on frozen cancer tissue sections. Conclusions: Taken together, our data provide evidence that TEM8 is a novel receptor for uPA, which may play a significant role in the regulation of tumor growth and metastasis. [ABSTRACT FROM AUTHOR]