The use of Low-Cost Particulate Matter Sensors and Their Future use with Unmanned Aircrafts

Atmospheric pollution is responsible for killing more than seven million people around the globe, according to the World Health Organization. Among the pollutants that contribute to air pollution, aerosols, defined as any liquid or solid particulate matter suspended or dispersed in the atmosphere, are a significant contributor to human morbidity and mortality. Current attempts to measure atmospheric PM are not only cumbersome and costly but also lack high spatiotemporal resolution. Recently, low cost sensors have been used to address these economic, practical, and technological shortcomings. This research aims at using LCSs in diverse environments and across different seasons in order to address the existing infrastructure’s spatial and temporal limitations. Commercial Low-cost sensors will be placed in three different operational modes in order to characterize the horizontal and vertical profiles of atmospheric PM. These modes vary in the dimensions that they sample: (1) stationary 1D collocated with a PM monitor based on the federal equivalent method at a suburban site, (2) mobile on a manned vehicle 2D touring the ERAU campus, and (3) mobile on unmanned vehicle 3D flying at urban, suburban, and rural sites. The different commercial LCSs will be used in this effort, relying on light scattering techniques or optical particle counters. Validation will take place by: (1) collocating LCSs with EPA monitoring stations, (2) comparing data to several other PM measurement devices, and (3) mounting a PM measurement device to a tethered balloon

The Healing Process of Intracorporeally and In Situ Devitalized Distal Femur by Microwave in a Dog Model and Its Mechanical Properties In Vitro

Background: Limb-salvage surgery has been well recognized as a standard treatment and alternative to amputation for patients with malignant bone tumors. Various limb-sparing techniques have been developed including tumor prosthesis, allograft, autograft and graft-prosthesis composite. However, each of these methods has short- and long-term disadvantages such as nonunion, mechanical failures and poor limb function. The technique of intracorporeal devitalization of tumor-bearing bone segment in situ by microwave-induced hyperthermia after separating it from surrounding normal tissues with a safe margin is a promising limb-salvage method, which may avoid some shortcomings encountered by the above-mentioned conventional techniques. The purpose of this study is to assess the healing process and revitalization potential of the devitalized bone segment by this method in a dog model. In addition, the immediate effect of microwave on the biomechanical properties of bone tissue was also explored in an in vitro experiment. Methods: We applied the microwave-induced hyperthermia to devitalize the distal femurs of dogs in situ. Using a monopole microwave antenna, we could produce a necrotic bone of nearly 20 mm in length in distal femur. Radiography, bone scintigraphy, microangiography, histology and functional evaluation were performed at 2 weeks and 1, 2, 3, 6, 9 and 12 months postoperatively to assess the healing process. In a biomechanical study, two kinds of bone specimens, 3 and 6 cm in length, were used for compression and three-point bending test respectively immediately after extracorporeall