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We report on the properties and function of two herpes simplex virus-1 (HSV-1) microRNAs (miRNAs) designated "miR-H28" and "miR-H29." Both miRNAs accumulate late in productive infection at a time when, for the most part, viral DNA and proteins have been made. Ectopic expression of miRNA mimics in human cells before infection reduced the accumulation of viral mRNAs and proteins, reduced plaque sizes, and at vey low multiplicities of infection reduced viral yields. The specificity of the miRNA mimics was tested in two ways. First, ectopic expression of mimics carrying mutations in the seed sequence was ineffective. Second, in similar tests two viral miRNAs made early in productive infection also had no effect. Both miR-H28 and miR-H29 are exported from infected cells in exosomes. A noteworthy finding is that both miR-H28 and miR-H29 were absent from murine ganglia harboring latent virus but accumulated in ganglia in which the virus was induced to reactivate. The significance of these findings rests on the principle that the transmission of HSV from person to person is by physical contact between the infected tissues of the donor and those of uninfected recipient. Diminished size of primary or recurrent lesions could be predicted to enhance person-to-person transmission. Reduction in the amount of reactivating latent virus would reduce the risk of retrograde transport to the CNS but would not interfere with anterograde transport to a site at or near the site of initial infection. [ABSTRACT FROM AUTHOR]

In this paper, we have synthesized Zn1-xAgxO (x = 0, 0.03, 0.06, and 0.09) nanorods (NRs) via the hydrothermal method at low temperature on silicon substrate. The characterization and comparison between the different Zn1-xAgxO samples, indicated that an increasing Ag concentration from x = 0 to a maximum of x = 0.09; All samples show a preferred orientation of (002) direction with no observable change of morphology. As the quantity of the Ag dopant was changed, the transmittances, as well as the optical band gap were decreased. X-ray photoelectron spectroscopy data clearly indicate the presence of Ag in ZnO crystal lattice. A nanoindentation-based technique was used to measure the effective piezo-response of different concentrations of Ag for both direct and converse effects. The value of the piezoelectric coefficient (d33) as well as the piezo potential generated from the ZnO NRs and Zn1-xAgxO NRs was found to decrease with the increase of Ag fraction. The finding in this investigation reveals that Ag doped ZnO is not suitable for piezoelectric energy harvesting devices. [ABSTRACT FROM AUTHOR]

The stress response genes encoding GADD45γ and to a lesser extent GADD45β are activated early in infection with HSV-1. Cells depleted of GADD45γ by transfection of shRNA or in which the gene had been knocked out (ΔGADD45γ yield significantly less virus than untreated infected cells. Consistent with lower virus yields the ΔGADD45γ cells, both uninfected or infected with HSV-1 exhibit significantly higher levels of transcripts encoding a cluster of a network of innate immunity genes that include those encoding IFI16, IFIT1, MDA5 and RIG-I. Members of this cluster of genes have been reported by this laboratory to be activated concurrent with significantly reduced virus yields in cell depleted of LGP2 or HDAC4. We conclude the following: (i) Innate immunity to HSV-1 is normally repressed in unstressed cells. The repression appears to be determined by two mechanisms. The first, illustrated here is by activation by HSV-1 infection of the gene encoding GADD45γ. The second mechanism requires constitutively active expression of LGP2 and HDAC4. [ABSTRACT FROM AUTHOR]

Electrochemistry is an old but still flourishing field of research due to the importance of the efficiency and kinetics of electrochemical reactions in industrial processes and (bio-)electrochemical devices. The heterogeneous electron transfer from an electrode to a reactant in the solution has been well studied for metal, semiconductor, metal oxide, and carbon electrodes. For those electrode materials, there is little correlation between the electronic transport within the electrode material and the electron transfer occurring at the interface between the electrode and the solution. Here, we investigate the heterogeneous electron transfer between a conducting polymer electrode and a redox couple in an electrolyte. As a benchmark system, we use poly(3,4-ethylenedioxythiophene) (PEDOT) and the Ferro/ferricyanide redox couple in an aqueous electrolyte. We discovered a strong correlation between the electronic transport within the PEDOT electrode and the rate of electron transfer to the organometallic molecules in solution. We attribute this to a percolation-based charge transport within the polymer electrode directly involved in the electron transfer. We show the impact of this finding by optimizing an electrochemical thermogalvanic cell that transforms a heat flux into electrical power. The power generated by the cell increased by four orders of magnitude on changing the morphology and conductivity of the polymer electrode. As all conducting polymers are recognized to have percolation transport, we believe that this is a general phenomenon for this family of conductors. [ABSTRACT FROM AUTHOR]

In this paper, we show that the possibility of using polyethylene glycol (EG) as a hydrogen source and it is used to assist the hydrothermal synthesis of ZnO nanorods (ZNRs). EG doping in ZNRs has been found to significantly improve their optical and chemical sensing characteristics toward glutamate. The EG was found to have no role on the structural properties of the ZNRs. However, the x-ray photoelectron spectroscopy (XPS) suggests that the EG could induce donor impurities effect in ZnO. Photoluminescence (PL) and UV-Vis. spectra demonstrated this doping effect. Mott-Schottky analysis at the ZNRs/electrolyte interface was used to investigate the charge density for the doped ZNRs and showed comparable dependence on the used amount of EG. Moreover, the doped ZNRs were used in potentiometric measurements for glutamate for a range from 10-6 M to 10-3 M and the potential response of the sensor electrode was linear with a slope of 91.15 mV/decade. The wide range and high sensitivity of the modified ZNRs based glutamate biosensor is attributed to the doping effect on the ZNRs that is dictated by the EG along with the high surface area-to-volume ratio. The findings in the present study suggest new avenues to control the growth of n-ZnO nanostructures and enhance the performance of their sensing devices. [ABSTRACT FROM AUTHOR]

Hexagonal c-axis oriented zinc oxide (ZnO) nanorods (NRs) with 120-300 nm diameters are synthesized via the low temperature aqueous chemical route at 80 °C on silver-coated glass substrates. The influence of varying the precursor solutions stirring durations on the concentration and spatial distributions of deep level defects in ZnO NRs is investigated. Room temperature micro-photoluminesnce (μ-PL) spectra were collected for all samples. Cathodoluminescence (CL) spectra of the as-synthesized NRs reveal a significant change in the intensity ratio of the near band edge emission (NBE) to the deep-level emission (DLE) peaks with increasing stirring durations. This is attributed to the variation in the concentration of the oxygen-deficiency with increasing stirring durations as suggested from the X-ray photoelectron spectroscopy analysis. Spatially resolved CL spectra taken along individual NRs revealed that stirring the precursor solutions for relatively short duration (1-3 h), which likely induced high super saturation under thermodynamic equilibrium during the synthesis process, is observed to favor the formation of point defects moving towards the tip of the NRs. In contrary, stirring for longer duration (5-15 h) will induce low super saturation favoring the formation of point defects located at the bottom of the NRs. These findings demonstrate that it is possible to control the concentration and spatial distribution of deep level defects in ZnO NRs by varying the stirring durations of the precursor solutions. [ABSTRACT FROM AUTHOR]

Printed electronics are considered for wireless electronic tags and sensors within the future Internet-of-things (loT) concept. As a consequence of the low charge carrier mobility of present printable organic and inorganic semiconductors, the operational frequency of printed rectifiers is not high enough to enable direct communication and powering between mobile phones and printed e-tags. Here, we report an all-printed diode operating up to 1.6 GHz. The device, based on two stacked layers of Si and NbSi2 particles, is manufactured on a flexible substrate at low temperature and in ambient atmosphere. The high charge carrier mobility of the Si microparticles allows device operation to occur in the charge injection-limited regime. The asymmetry of the oxide layers in the resulting device stack leads to rectification of tunneling current. Printed diodes were combined with antennas and electrochromic displays to form an all-printed e-tag. The harvested signal from a Global System for Mobile Communications mobile phone was used to update the display. Our findings demonstrate a new communication pathway for printed electronics within loT applications. [ABSTRACT FROM AUTHOR]