Current conductive materials for use in cardiac regeneration are limited by cytotoxicity or cost in implementation. In this manuscript, we demonstrate for the first time the application of a biocompatible, conductive polypyrrole-polycaprolactone film as a platform for culturing cardiomyocytes for cardiac regeneration. This study shows that the novel conductive film is capable of enhancing cell-cell communication through the formation of connexin-43, leading to higher velocities for calcium wave propagation and reduced calcium transient durations among cultured cardiomyocyte monolayers. Furthermore, it was demonstrated that chemical modification of polycaprolactone through alkaline-mediated hydrolysis increased overall cardiomyocyte adhesion. The results of this study provide insight into how cardiomyocytes interact with conductive substrates and will inform future research efforts to enhance the functional properties of cardiomyocytes, which is critical for their use in pharmaceutical testing and cell therapy.

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Impedance measurement was conducted at the entire cell level for studying of the Ni-MH rechargeable batteries. An improved equivalent circuit model considering diffusion process is proposed for simulation of battery impedance data at different charge input levels. The cell capacity decay was diagnosed by analyzing the ohmic resistance, activation resistance, and mass transfer resistance of the Ni-MH cells with degraded capacity. The capacity deterioration of this type, Ni-MH cell, is considered in relation to the change of activation resistance of the nickel positive electrodes. Based on the report and surface analysis obtained from the energy dispersive X-ray spectroscopy, the composition formula of metal-hydride electrodes can be closely documented as the AB5 type alloy and the “A” elements are recognized as lanthanum (La) and cerium (Ce). The capacity decay of the Ni-MH cell is potentially initiated due to starved electrolyte for the electrochemical reaction of active materials inside the Ni-MH battery, and the discharge product of Ni(OH)2 at low state-of-charge level is anticipated to have more impeding effects on electrode kinetic process for higher power output and efficient energy delivery.

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Reaction of thiophene with the ultradeep desulfurization sorbent Ag/titania under ambient conditions was studied by the multiple complementary temperature-programmed techniques: electron spin resonance (ESR), high-vacuum temperature-programmed desorption (HV-TPD), high-vacuum temperature-programmed reaction spectroscopy (HV-TPRS) and by X-ray photoelectron spectroscopy (XPS). Sorption of thiophene at 25−75 °C proceeds via strong molecular adsorption. Decomposition of the adsorption complex “Ag/titania + thiophene” occurs in a stage-wise fashion. At ∼75 to 175 °C, the adsorption complex decomposes without reaction with molecular oxygen. Adsorbed thiophene molecularly desorbs at ∼90 °C (desorption energy = 105 kJ/mol). At ∼75 to 175 °C, the nonoxidative pyrolysis of the adsorption complex with the C−S scission and desorption of butadiene proceeds. At ∼225 to 525 °C, molecular oxygen participates in thermal decomposition of the adsorption complex to form SO2. Under the deficiency of O2, the hydrogen-lean “coke” C x H y (x ≫ y) is formed. The combination of temperature-programmed ESR, TPD/TPRS, and XPS is well-suited to investigate the molecular-level mechanisms of adsorption, desorption, and surface chemical reactions of the sulfur-containing adsorbates.