A facile approach to fabricate graphene based piezoresistive strain sensor on paper substrate

Sensors, FETs and chemi resistors are few of the devices which show potential in the area of flexible electronics for health monitoring applications. In the present work, piezoresistive strain sensors based on graphite and graphene on cellulose paper substrate has been reported. Graphite sensor has been fabricated by rubbing pencil on paper and graphene sensor by directly coating graphene ink using paint brush. The resistance of the fabricated sensor increases with outwards bending and vice-versa, further the piezoresistive effect has also been evaluated by applying variable longitudinal stress. A comparative study of gauge factor (GF) depending upon different type of strains has been presented and it has been observed that the GF of graphene piezoresistive strain sensor decreases with increase in number of layers, the GF for graphene sensor is higher as compared to graphite sensor. Fabricated piezoresistive strain sensors may find applications as human body motion detection, gait analysis etc

Self-energy of an electron due to electron-phonon interaction in alkali metals : Its dependence on phonon dispersion relation and realistic electron-electron screening

764-773The electron mass-enhancement factor, λ, due to electron-phonon interaction, has been evaluated considering realistic description , both for electrons and phonons. Explicit analytical expressions for λ have been derived for dispersionless, highly dispersive and intermediately dispersive phonons when the electron screening is given by Thomas-Fermi model. Different types of electron screening which incorporate electron-electron interaction much beyond Thomas-Fermi have also been considered. Computation of λ for all alkali metals have been made and compared with the corresponding experimental and other theoretical results

Verruco-papillary lesions in relation to human papilloma virus

Plethora of pathologic conditions may affect the normal morphologic characteristics and intactness of the oral mucosa, presenting as surface alterations.The prevalence of the different types of HPV worldwide has implications for the effectiveness of HPV vaccinations against HPV-induced carcinogenesis. This article discusses HPV related lesions with emphasis on verrucopapillary lesions