Traumatic brain injury (TBI) alters function and behavior, which can be characterized by changes in electrophysiological function in vitro. A common cognitive deficit after mild-to-moderate TBI is disruption of persistent working memory, of which the in vitro correlate is long-lasting, neuronal network synchronization that can be induced pharmacologically by the gamma-aminobutyric acid A antagonist, bicuculline. We utilized a novel in vitro platform for TBI research, the stretchable microelectrode array (SMEA), to investigate the effects of TBI on bicuculline-induced, long-lasting network synchronization in the hippocampus. Mechanical stimulation significantly disrupted bicuculline-induced, long-lasting network synchronization 24 h after injury, despite the continued ability of the injured neurons to fire, as revealed by a significant increase in the normalized spontaneous event rate in the dentate gyrus (DG) and CA1. A second challenge with bicuculline 24 h after the first challenge significantly decreased the normalized spontaneous event rate in the DG. In addition, we illustrate the utility of the SMEA for TBI research by combining multiple experimental paradigms in one platform, which has the potential to enable novel investigations into the mechanisms responsible for functional consequences of TBI and speed the rate of drug discovery.

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The electrical resistance of gold film conductors on polydimethyl siloxane substrates at stages of uniaxial stretching is measured and modeled. The surface area of a gold conductor is assumed constant during stretching so that the exposed substrate takes up all strain. Sheet resistances are calculated from frames of scanning electron micrographs by numerically solving for the electrical potentials of all pixels in a frame. These sheet resistances agree sufficiently well with values measured on the same conductors to give credence to the model of a stretchable network of gold links defined by microcracks.

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Devices with the structure of ITO/Pentacene/C60/Al were prepared. Then, in order to enhance the performance of these cells and study the mechanism of the cathodic buffer layer, bathocuproine (BCP) of different thickness were inserted between C60 and Al. When inserting 10 nm BCP, the power conversion effciency of the cell is as high as 0.46%. On this basis, bathophenanthroline (Bphen) and 3, 4, 9, 10-Perylenetetracarb-oxylicdianhydride (PTCDA) are used instead of BCP, so as to compare and discuss the effects on the performance of the solar cells caused by the electron mobility and optical absorption properties of the cathodic buffer layers. As the electron mobility of Bphen is two orders of magnitude higher than that of BCP, the efficiency of devices with Bphen as the buffer layer was improved to 0.56%. Furthermore, the absorption spectrum of devices was obviously enhanced by inserting PTCDA material which has large absorption in visible light region, and the highest current density of such device was enhanced to 5.97 mA/cm2 and the efficiency was 0.87%.