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A compact, low-profile, and ultra-wideband antenna is always desirable for airborne Unmanned Aerial Vehicles (UAV) applications. In this paper, an ultra-wideband monopole antenna is presented with the benefit of a compact and low-profile design structure. The antenna design enables efficient communication without interfering with the UAV’s other components. The antenna is designed using a slotted-hexagonal-patch fed from a co-planar microstrip feed. The bow-tie-shaped slot along with a few other rectangular-shaped parasitic slots are loaded in the hexagonal patch for bandwidth enhancement. The coplanar feed with top ground offers minimum interference with the UAV structure. The non-conducting bottom plane allows seamless integration without causing any interference to the antenna. An equivalent circuit model (ECM) of the proposed antenna is also developed. The antenna structure is fabricated and the measured results are validated. A good agreement between the measured and simulated results is observed. The antenna covers an ultra-wideband ranging from 3 GHz to 13.5 GHz with a maximum gain of 4.0dBi. The size of the antenna is 0.24λ0 ×0.29λ0 ×0.01λ0. The developed antenna, therefore, demonstrates that it is a strong contender for ultra-wideband UAV-based applications. [ABSTRACT FROM AUTHOR]

The major component for the effective functioning of airborne unmanned aerial vehicles (UAVs) is an antenna. The unified integration of an antenna with UAVs without disturbing the other components of UAVs, compact size, thin, and wideband antennas are preferred. Based on these prerequisites, a low-profile and a wideband antenna is presented for autonomous UAVs for C-band applications. The antenna is designed on an extremely thin substrate of size 0.01 λ 0 without compromising the antenna's broad bandwidth. The antenna structure comprises a corrugated U-shaped patch, a few parasitic patches along with the partial ground. Initially, only a single mode was excited using a U-shaped patch, then further on introducing a few more parasitic patches along with corrugations in a U-shaped patch other modes were also coupled leading to enhancement in the bandwidth of the antenna. The proposed antenna along with a 2 × 2 quad-port multiple input, multiple output (MIMO) antenna is designed and fabricated. The measured results are found to be in good agreement with the simulated results. A broad bandwidth of 74.5% (4.1–9.0 GHz) with 5.02 dBi peak gain at 6.6 GHz is exhibited by the fabricated MIMO antenna. Thus, the designed antenna proves to be an effective candidate for UAV-based C-band applications. [ABSTRACT FROM AUTHOR]

Topical minoxidil is used for treating different hair disorders. Even though it is an effective therapy, many patients show poor compliance due to the cost, side effects, and duration of treatment. Topical minoxidil is the mainstay treatment for androgenetic alopecia (AGA). Recently, low alcohol or alcohol-free topical minoxidil formulation has proven to be an alternative for patients suffering from AGA, including those with poor compliance with other therapies. Thus, the current article provides the positioning of low alcohol or alcohol-free topical minoxidil to manage AGA in Indian clinical practice. [ABSTRACT FROM AUTHOR]

The work reported in this paper was focused on the investigation of surface morphological, microstructural, and optical features of polycrystalline BaTiO3 thin film deposited on p-type Si < 100 > substrate using e-beam PVD (physical vapor deposition) technique. The influence of annealing on the surface morphology of the thin film was analyzed by X-ray diffraction, atomic force microscopy and scanning electron microscopy. When the annealing temperature was increased from as-deposited to 800 °C there was a significant growth in the grain size from 28.407 to 37.89 nm. This granular growth of BaTiO3 made the thin film appropriate for nanoelectronic device applications. The roughness of the annealed film was increased from 31.5 to 52.8 nm with the annealing temperature. The optical bandgap was computed using Kubelka-Munk (KM) method which was reduced from 3.93 to 3.87 eV for the as-deposited to the 800 °C annealed film. The above reported properties made the annealed film suitable for optoelectronic applications. For polycrystalline BaTiO3 thin film the refractive index varied from 2.2 to 1.98 from 400 to 500 nm and it was 2.05 at 550 nm wavelength. The broad peaks in Raman spectra indicated the polycrystalline nature of the thin film. It was also observed that with the annealing temperature the intensity of the Raman peaks increased. From these results, it was proved that annealing significantly improved the crystallinity, microstructural, surface morphological and optical features of the barium titanate thin film which made it suitable as potential sensors in biomedical applications as it is cost-effective, lead-free and environment friendly material. [ABSTRACT FROM AUTHOR]

This paper presents the study of surface morphological, optical and microstructural features of zinc oxide (ZnO) nanofilm layered upon p-type Si substrate of <100> orientation by employing conventional RF magnetron sputtering system at different annealing temperatures. The effect of annealing on the nano-film is examined using different characterization techniques such as Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), FTIR (Fourier Transform Infrared Spectroscopy), UV-vis spectroscopy and Raman spectroscopy. The sharp diffraction peak at (002) orientation is seen by the XRD spectra which signifies a better growth of single crystalline thin film along the z-axis with the hexagonal wurtzite crystal structure. The surface morphological study shows that the grain size of the thin film intensifies from 22.06 nm to 36.77 nm when the annealing temperature is increased whereas there is a decrease in the values of lattice constants (a=b, c), FWHM (full width at half maximum), residual stress, lattice strain and dislocation density by increasing annealing temperature. The enhancement in the grain size makes the thin film appropriate for MEMS device applications including piezoelectric energy harvesters, gas sensors, etc. The optical bandgap of the ZnO thin film is estimated using Kubelka-Munk (KM) approach and it decreases from 3.23 to 3.16 eV for As-deposited, 400 °C, 600 °C and 800 °C respectively which makes the annealed thin film apposite for optoelectronic device applications. The intensity of the Raman peaks strengthens with the annealing temperature. These results prove that the annealing extensively enhances the crystallinity, structural, morphological and optical features of ZnO thin film and hence becomes suitable for nanoelectronic device applications. [ABSTRACT FROM AUTHOR]