Do TETRA (Airwave) base station signals have a short-term impact on health and well-being? A randomized double-blind provocation study

Background: "Airwave" is the new communication system currently being rolled out across the United Kingdom for the police and emergency services, based on the Terrestrial Trunked Radio Telecommunications System (TETRA). Some police officers have complained about skin rashes, nausea, headaches, and depression as a consequence of using their Airwave handsets. In addition, a small subgroup in the population self-report being sensitive to electromagnetic fields (EMFs) in general. Objectives: We conducted a randomized double-blind provocation study to establish whether short-term exposure to a TETRA base station signal has an impact on the health and well-being of individuals with self-reported "electrosensitivity" and of participants who served as controls.Methods: Fifty-one individuals with self-reported electrosensitivity and 132 age and sex-matched controls participated in an open provocation test; 48 sensitive and 132 control participants went on to complete double-blind tests in a fully screened semianechoic chamber. Heart rate, skin conductance, and blood pressure readings provided objective indices of short-term physiological response. Visual analog scales and symptom scales provided subjective indices of well-being.Results: We found no differences on any measure between TETRA and sham (no signal) under double-blind conditions for either controls or electrosensitive participants, and neither group could detect the presence of a TETRA signal at rates greater than chance (50%). When conditions were not double blind, however, the self-reported electrosensitive individuals did report feeling worse and experienced more severe symptoms during TETRA compared with sham.Conclusions: Our findings suggest that the adverse symptoms experienced by electrosensitive individuals are due to the belief of harm from TETRA base stations rather than to the low-level EMF exposure itself

Assessing the Natural Recovery of Mangroves after Human Disturbance Using Neural Network Classification and Sentinel-2 Imagery in Wunbaik Mangrove Forest, Myanmar

In this study, we examined the natural recovery of mangroves in abandoned shrimp ponds located in the Wunbaik Mangrove Forest (WMF) in Myanmar using artificial neural network (ANN) classification and a change detection approach with Sentinel-2 satellite images. In 2020, we conducted various experiments related to mangrove classification by tuning input features and hyper-parameters. The selected ANN model was used with a transfer learning approach to predict the mangrove distribution in 2015. Changes were detected using classification results from 2015 and 2020. Naturally recovering mangroves were identified by extracting the change detection results of three abandoned shrimp ponds selected during field investigation. The proposed method yielded an overall accuracy of 95.98%, a kappa coefficient of 0.92, mangrove and non-mangrove precisions of 0.95 and 0.98, respectively, recalls of 0.96, and F1 scores of 0.96 for the 2020 classification. For the 2015 prediction, transfer learning improved model performance, resulting in an overall accuracy of 97.20%, a kappa coefficient of 0.94, mangrove and non-mangrove precisions of 0.98 and 0.96, respectively, recalls of 0.98 and 0.97, and F1 scores of 0.96. The change detection results showed that mangrove forests in the WMF slightly decreased between 2015 and 2020. Naturally recovering mangroves were detected at approximately 50% of each abandoned site within a short abandonment period. This study demonstrates that the ANN method using Sentinel-2 imagery and topographic and canopy height data can produce reliable results for mangrove classification. The natural recovery of mangroves presents a valuable opportunity for mangrove rehabilitation at human-disturbed sites in the WMF

Cognitive and physiological responses in humans exposed to a TETRA base station signal in relation to perceived electromagnetic hypersensitivity

Terrestrial Trunked Radio (TETRA) technology ("Airwave") has led to public concern because of its potential interference with electrical activity in the brain. The present study is the first to examine whether acute exposure to a TETRA base station signal has an impact on cognitive functioning and physiological responses. Participants were exposed to a 420MHz TETRA signal at a power flux density of 10mW/m as well as sham (no signal) under double-blind conditions. Fifty-one people who reported a perceived sensitivity to electromagnetic fields as well as 132 controls participated in a double-blind provocation study. Forty-eight sensitive and 132 control participants completed all three sessions. Measures of short-term memory, working memory, and attention were administered while physiological responses (blood volume pulse, heart rate, skin conductance) were monitored. After applying exclusion criteria based on task performance for each aforementioned cognitive measure, data were analyzed for 36, 43, and 48 sensitive participants for these respective tasks and, likewise, 107,125, and 129 controls. We observed no differences in cognitive performance between sham and TETRA exposure in either group; physiological response also did not differ between the exposure conditions. These findings are similar to previous double-blind studies with other mobile phone signals (900-2100MHz), which could not establish any clear evidence that mobile phone signals affect health or cognitive function

A comprehensive assessment of ground motions from two 2016 intra-slab earthquakes in Myanmar

We map the distribution of macroseismic intensities from the MW 6.9 Kani and the MW 6.8 Chauk intra-slab earthquakes in 2016 in Myanmar using the 1998 European Macroseismic Scale (EMS-98) by interpreting data gathered from field surveys, community responses sent via social media to the Myanmar Earthquake Committee (MEC), and digital news reports. Our macroseismic maps for both events provide better spatial data coverage in Myanmar, India, and Bangladesh than community derived macroseismic maps (e.g., U.S. Geological Survey's “Did You Feel It?”). In Myanmar, this was driven by improved telecommunication that has allowed social media such as the Burmese language Facebook portal of the Myanmar Earthquake Committee (MEC) to reach into rural areas from where reports of shaking effects from earthquakes have been previously unavailable. Our analysis of both the macroseismic intensities and strong motion observations from India and Myanmar suggests the two earthquakes had different source properties. The comparison of our intensity data with instrumental strong motion records also suggests the peak ground motion-intensity relationship by Worden et al. (2012) generally performs well for both earthquakes. In addition, ground motion behaviour within the Burma and Indian plates can be related to different existing ground motion prediction equations (GMPEs) and intensity prediction equations (IPEs) for subduction zones and for stable continental regions respectively. We therefore suggest these effects will need to be considered in future regional seismic hazard models or Shake Maps for this region when evaluating the impact of the future events.NRF (Natl Research Foundation, S’pore)MOE (Min. of Education, S’pore)Published versio