Flexible Indium-Tin Oxide Crystal on Plastic Substrates Supported by Graphene Monolayer

Flexible and crystallized indium-tin oxide (ITO) thin films were successfully obtained on plastic polyethylene terephthalate (PET) films with monolayered graphene as a platform. The highly crystalline ITO (c-ITO) was first fabricated on a rigid substrate of graphene on copper foil and it was subsequently transferred onto a PET substrate by a well-established technique. Despite the plasma damage during ITO deposition, the graphene layer effectively acted as a Cu-diffusion barrier. The c-ITO/graphene/ PET electrode with the 60-nm-thick ITO exhibited a reasonable sheet resistance of similar to 45 Omega sq(-1) and a transmittance of similar to 92% at a wavelength of 550 nm. The c-ITO on the monolayered graphene support showed significant enhancement in flexibility compared with the ITO/PET film without graphene because the atomically controlled monolayered graphene acted as a mechanically robust support. The prepared flexible transparent c-ITO/graphene/PET electrode was applied as the anode in a bulk heterojunction polymer solar cell (PSC) to evaluate its performance, which was comparable with that of the commonly used c-ITO/glass electrode. These results represent important progress in the fabrication of flexible transparent electrodes for future optoelectronics applications

Raman Characterization and Polarity Tuning of Aligned Single-Walled Carbon Nanotubes on Quartz

Raman characterization has been employed to study key features of highly aligned single-walled carbon nanotubes grown on quartz substrates. The nanotubes are observed to possess an estimated metallic/semiconducting ratio of 1:2.7, and Raman spectra also confirm the high integrity of nanotubes before and after being transferred from quartz to Si/SiO2 substrates. Based on the as-grown and the transferred aligned nanotubes, we have further fabricated top- and back-gated nanotube devices, respectively. The top-gated transistors exhibit ambipolar transport characteristics with high transconductance, small subthreshold swing of 110 mV/decade and on/off ratio of 107, while the back-gated transistors show unipolar p-type characteristics. Furthermore, we have demonstrated polarity tuning to produce both predominately n- and p-type top-gated carbon nanotube transistors by controlling the polarity of gate voltage during electrical breakdown, which has great potential for building complementary carbon nanotube circuits.Chemistry and Chemical Biolog

Regulation of innate and adaptive immunity by Notch.

Coordinated function of the innate and adaptive arms of the immune system in vertebrates is essential to promote protective immunity and to avoid immunopathology. The Notch signalling pathway, which was originally identified as a pleiotropic mediator of cell fate in invertebrates, has recently emerged as an important regulator of immune cell development and function. Notch was initially shown to be a key determinant of cell-lineage commitment in developing lymphocytes, but it is now known to control the homeostasis of several innate cell populations. Moreover, the roles of Notch in adaptive immunity have expanded to include the regulation of T cell differentiation and function. The aim of this Review is to summarize the current status of immune regulation by Notch. A better understanding of Notch function in both innate and adaptive immunity will hopefully provide multiple avenues for therapeutic intervention in disease