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Rapid urbanization has inevitably raised challenges by indirectly adding industry waste to the environment. This problem becomes even more severe when contamination of consumable water is considered. As a leading sector in semiconductor‐related research to face such challenges, gallium oxide and its derivatives have shown remarkable performance by exhibiting controlled, recyclable photocatalytic activities. This work demonstrates the enhancement of the photocatalytic performance of β‐Ga2O3, which is related to the structural and morphological variation induced by rGO wrapping. Firstly, the Ga2O3 nanostructures are obtained by calcinating gallium oxide hydroxide (GaOOH), which is synthesized via a simple chemical route. On the other hand, rGO wrapped β‐Ga2O3 is synthesized using in‐situ hydrothermal treatment. In addition to traditional characterizations such as X‐ray diffractometry (XRD), field emission scanning electron microscopy (FESEM), high‐resolution transmission electron microscopy (HRTEM), Raman spectroscopy, etc., the photocatalytic performance of both pristine and composite systems is studied by time‐dependent UV–Vis absorption spectrum for the degradation of different organic toxic pollutants. It is observed that the composite sample exhibited a larger effective surface area and enhanced optical absorption in the UV–Vis range as compared to the pristine gallium oxide sample. Under UV light irradiation, the rGO wrapped β‐Ga2O3 nanobars can degrade rhodamine B dye entirely within 25 min and exhibit a higher photodegradation rate of 0.1598 min−1 which became 3.5 times higher as compared to that of pure gallium oxide. [ABSTRACT FROM AUTHOR]

Byline: Nirmalya. Das, Abhishek. De, Biswanath. Naskar, Amrita. Sil, Sudip. Das, Aarti. Sarda, Gobinda. Chatterjee Background: Leprosy is a chronic infectious disease caused by Mycobacterium leprae affecting the skin, peripheral [...]

In this paper, we propose a machine-based classification technique using the scattering parameters obtained using a wearable wideband textile antenna to diagnose breast tumors. The breast phantom is formed following the dielectric properties of the human breast tissues and characterized to ensure the resemblance with a actual tissue model for the range of frequencies from 3 to 10 GHz. A biocompatible textile antenna is fabricated and embedded on an artificial breast phantom model to capture the variation of the reflection coefficient S 11 and the transmission coefficient S 21 for frequencies 3–10 GHz for different locations and sizes of tumors within the phantom model. Support vector machine is used to classify the healthy tissues from the malignant tumors based on the variation of the scattering parameters owing to the variation of the dielectric characteristics of the breast phantom model. The proposed method offers 84% and 89% accuracy while using S 11 and S 21 parameters alone for the analysis. However, the results further improve up to 93% as a combination of S 11 and S 21 signals is considered. [ABSTRACT FROM AUTHOR]

Mapping of infectious diseases like COVID-19 is the foremost importance for diseases control and prevention. This study attempts to identify the spatio-temporal pattern and evolution trend of COVID-19 at the district level in India using spatial statistical models. Active cases of eleven time-stamps (30 March–2 December, 2020) with an approximately 20-day interval are considered. The study reveals applications of spatial statistical tools, i.e. optimised hotspot and outlier analysis (which follow Gi* and Moran I statistics) and emerging hotspot with the base of space time cube, are effective for the spatio-temporal evolution of disease clusters. The result shows the overall increasing trend of COVID-19 infection with a Mann–Kendall trend score of 2.95 (p = 0.0031). The spatial clusters of high infection (hotspots) and low infection (coldspots) change their location over time but are limited to the districts of the south-western states (Kerala, Karnataka, Andhra Pradesh, Maharashtra, Gujarat) and the north-eastern states (West Bengal, Jharkhand, Assam, Tripura, Manipur, etc.) respectively. A total of eight types of patterns are identified, but the most concerning types are consecutive (7.24% of districts), intensifying (15.13% districts) and persistent (24.34% of districts) which will help health policy makers and the government to prioritize-based resource allocation and control measures. [ABSTRACT FROM AUTHOR]

Two-dimensional topological insulator bismuth selenide (Bi2Se3) nanosheets (NSs) embedded in poly-methyl methacrylate (PMMA) are employed for the first time for the resistive switching (RS) application. Hexagonal 2D Bi2Se3 NSs are synthesized by a simple solvothermal method and combine with PMMA at different weight percentages of 2D Bi2Se3. Field emission scanning electron microscopy and transmission electron microscopy along with other characterizations such as X-ray photoelectron spectroscopy and Raman spectroscopy were performed for the characterization of Bi2Se3@PMMA hybrid system. The composite was deposited on a transparent, flexible polyethylene terephthalate substrate to form Ag/Bi2Se3@PMMA/indium doped tin oxide memory cell. I-V characteristics of the device revealed a stable and non-volatile memory effect. The device shows a significantly high resistance (RHRS/RLRS) ratio, more than 103, high retention time (more than 9000 s) with high reproducibility over a large number of (105) ac cycles. From the experimental data, RS performances are explained by using a charge trapping–detrapping mechanism. Owing to the increasing interest in flexible electronics, bending tests are carried out at various bending diameters (10–30 mm) to show the mechanical robustness of the proposed device. [ABSTRACT FROM AUTHOR]