Polymer/fullerene solar cells are printed on paper using a combination of gravure and flexographic printing techniques. The printed paper photovoltaic cells are free from expensive electrodes made with indium–tin oxide, silver, or gold. Oxidized zinc film is used as the electron‐collecting layer.

Mechanical strain energies in the form of movements/vibrations caused by human, machine or wind are available all around us in large quantities. A substantial amount of this renewable energy can be harvested by using piezoelectric devices. [ 1 ] Various piezoelectric energy harvesting devices (PEHDs) have been reported, mainly targeting small area applications. For example, small area PEHDs are effi cient enough to harvest substantial quantity of biological energy by human movement or by body bending. [ 2 ] According to a recent report, a mixture of BaTiO 3 nanoparticles and carbon nanotubes dispersed in a polymer matrix can generate up to 3.2 V. [ 3 ] BaTiO 3 thin fi lm based nanogenerators have been reported with an output voltage of 1.0 V and a current density of 0.19 μ A cm -2 . [ 4 ] A hybrid nanogenerator based on ZnO nanowire/poly(vinylidene fl uoride-trifl uorethylene) has been reported with output voltage, current density and power density of 0.1 V, 10 nA cm -2 and 16 μ W cm -3 , respectively. [ 5 ] Piezoelectric power generation from ZnO fi lm can be enhanced 18-fold by an addition of a p-type semiconducting polymer on top of it. [ 6 ] All these PEHDs are developed to harvest mechanical strain energy only from small areas. However, PEHDs can be used to harvest mechanical strain energy available on larger areas too. For example, PEHDs placed on a fl oor can generate energy when people walk over it. A large area sheet of PEHD in the form of a fl ag can be hung outside to harvest energy from wind. Production of large area PEHDs requires a method that can produce them in a cost effective manner with a high production speed. Roll-to-roll printing techniques, i.e., gravure, fl exography, offset and screen, can be effectively used to produce PEHDs for large area applications. These are wellestablished production techniques, available all over the world for printing applications. An advantage of fl exography printing is that it is a relatively inexpensive printing process, used mostly for package printing. For a larger area printing, which does not require a high resolution, it is a suitable production technique. In the last decade many innovative electronic components have been developed by using roll-to-roll printing methods. [7][8][9] Recently, our group has reported printed organic solar cells on a roll of paper by using gravure and fl exographic printing methods. [ 10 ] We also have reported piezoelectric loudspeakers printed by fl exography on a paper substrate. [ 11 ] Here, we report on a PEHD that is fully printed by the fl exographic printing method in ambient conditions. Although lead zirconate titanate (PZT) is one of the best piezoelectric materials, its application in energy harvesting is limited because of its mechanical rigidity. Recently, many approaches have been made to develop fl exible PZT based PEHDs, i.e., PZT ribbons and PZT fi ber composite. [ 12,13 ] As PEHDs generate alternating currents (AC), they can not be used directly to run most of the electronic devices, which require DC current...

Introduction: Epilepsy is a group of chronic neurological disorders characterized by seizures. Kindling, a chronic epileptic mouse model, was used to explore the epileptogenic mechanism and seek new anti-epileptics. In kindling, sub-convulsive (chemical/ electrical) stimuli were delivered repeatedly and erratically, eventually causing massive convulsions. Moreover, Morinda citrifolia (Noni) extracts are used as a remedy in ayurvedic preparations for many ailments. Noni has recently been shown to protect mice from amyloid beta-induced memory loss. Objective: This study was used to investigate the neuroprotective potential of Morinda citrifolia in mice over pentylenetetrazol (PTZ)-induced kindling seizure. Method: Kindling was provoked by subsequent (one-day-gap) injections of PTZ (subconvulsive; 35 mg/kg; s.c.) for 29 days in mice. Following PTZ injection, convulsive behaviours were noted for 30 minutes. Open-field-test (locomotor activity), forced swimming test (depressive behaviors), elevated plus-maze, and passive avoidance tests were employed to evaluate cognition. Brain homogenate was used to estimate oxidative stress (glutathione, superoxide-dismutase, lipid-peroxidation) and acetylcholinesterase activity. Result: PTZ-provoked kindled mice displayed depressive behaviors, impaired locomotion, cognitive dysfunctions and various biochemical changes. However, treatment with Morinda citrifolia extract (500 and 1000 mg/kg, p.o) and valproic acid (200 mg/kg, p.o) before 60 min of each PTZ injection diminished kindling scores and restored behavioural, and biochemical changes. Conclusion: Our findings suggest Morinda citrifolia offered neuroprotective effects against PTZinduced kindling seizures in mice, which were established by behavioural and biochemical paradigms.

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