Study of small particles in the neighbourhood of the melting point

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An Innovative Approach for Environmental Monitoring by Solar Powered Kite

This study investigates the design of a solar powered kite equipped with sensors for any environmental data monitoring, such as, temperature, pressure and so on towards the elevated environment. The developed prototype transforms a traditional kite with a unique design approach that involves the upward height measurement, energy harvesting by solar cells as well as data transmission via wireless network. However, the results from initial monitoring shows only the vertical mapping of ambient temperature as the test case. The developed system can successfully sense and display the temperature data from various height within a certain range as found in the initial investigation. Therefore, upon monitoring various environmental parameters at any cases or during emergency situations using the solar-kite as the simple tool, decision can be made to take appropriate measures against any detrimental changes of the environment by other means

Long-Term Efficacy and Safety of Left Atrial Appendage Occlusion (LAAO) vs Direct Oral Anticoagulation (DOAC) in Patients with Atrial Fibrillation: A Systematic Review and Meta-Analysis.

BACKGROUND: Prevention of stroke by anticoagulation is essential in patients with Atrial fibrillation (AF); with direct oral anticoagulants (DOACs) being preferred over warfarin in most patients. The Long-term efficacy and safety of DOACs vs. Left Atrial Appendage Occlusion (LAAO) remain unknown. METHODS: Electronic databases (PubMed, Embase, Scopus) were searched from inception to February 10th, 2021. The primary endpoint was cardiovascular mortality. Secondary outcomes included incidence of ischemic stroke/transient ischemic attack (TIA) and systemicembolism. The safety endpoint was clinically relevant bleeding (a composite of major or minor clinically relevant bleeding). RESULTS: A total of three studies with 3039 participants (LAAO = 1465; DOACs = 1574) were included. Mean age was 74.2 and 75.3 years in the LAAO and DOAC group respectively. Average follow-up period was 2 years. There was no difference in terms of cardiac mortality (RR 0.90, 95% CI 0.40-2.03; p = 0.81), ischemic stroke/TIA (RR 1.15, 95% CI 0.80-1.65; p = 0.46; I 2 = 0) and clinically significant bleeding (RR 0.77, 95% CI 0.50-1.17; p = 0.22; I 2 = 69) between the groups. CONCLUSIONS: Among patients with AF, LAAO was comparable to DOACs with similar efficacy and safety profiles

The Role of Deposition Temperature in the Photovoltaic Properties of RF-Sputtered CdSe Thin Films

Cadmium selenide (CdSe) thin films were grown on borosilicate glass substrates using the RF magnetron sputtering method. In this study, CdSe thin film was deposited at a deposition temperature in the range of 25 °C to 400 °C. The influence of deposition or growth temperature on the structural, morphological, and opto-electrical properties of CdSe films was investigated elaborately to achieve a good-quality window layer for solar-cell applications. The crystal structure, surface morphology, and opto-electrical characteristics of sputtered CdSe films were determined using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), UV–Vis spectrophotometry, and Hall effect measurement, respectively. The XRD results revealed the polycrystalline nature of CdSe, with a hexagonal structure having a strong preferential orientation toward the (002) plane. As evident from the FESEM images, the average grain size and surface morphology of the films were dependent on deposition temperatures. The carrier concentration was obtained as 1014 cm−3. The band gap in the range of 1.65–1.79 eV was found. The explored results suggested that sputtered CdSe thin film deposited at 300 °C has the potential to be used as a window layer in solar cells

Self-Sustained Autonomous Wireless Sensor Network with Integrated Solar Photovoltaic System for Internet of Smart Home-Building (IoSHB) Applications

Conventional wireless sensor networks (WSNs) in smart home-building (SHB) are typically driven by batteries, limiting their lifespan and the maximum number of deployable units. To satisfy the energy demand for the next generation of SHB which can interconnect WSNs to make the internet of smart home-building (IoSHB), this study introduces the design and implementation of a 250 mW to 2.3 W energy harvesting device. The proposed device is dynamically autonomous owing to the integration of embedded solar photovoltaic (PV) modules and power storage through a supercapacitor (SC; 5 V, 0.47 F) capable of powering WSNs for 95 s (up to 4.11 V). The deployed device can harvest indoor and outdoor ambient light at a minimum illumination of 50 lux and a maximum illumination of 200 lux. Moreover, the proposed system supports wireless fidelity (Wi-Fi) and Bluetooth Low Energy (BLE) to do data transfer to a webserver as a complete internet of things (IoT) device. A customized android dashboard is further developed for data monitoring on a smartphone. All in all, this self-powered WSN node can interface with the users of the SHBs for displaying ambient data, which demonstrates its promising applicability and stability