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EM behavior when the wavelength is about the same size as the object
Published in James R. Nagel, Cynthia M. Furse, Douglas A. Christensen, Carl H. Durney, Basic Introduction to Bioelectromagnetics, 2018
James R. Nagel, Cynthia M. Furse, Douglas A. Christensen, Carl H. Durney
External signals are often measured inadvertently with the desired bioelectromagnetic signals. For this reason, most often coaxial cable is used. Coax has a shield around the inner conductor to reduce interference between the outside world and the signal on the cable. Unfortunately, the outside signal (such as a radio station, a cell phone, and noise from electrical systems turning on and off) is often still picked up by the antennas and leaks into the system from many places. Truly quiet EM measurements in this frequency range must be made inside an anechoic chamber. This is a metal room with foam on the walls that is designed to absorb EM fields.
Biofield Devices
Published in Len Wisneski, The Scientific Basis of Integrative Health, 2017
Len Wisneski, Blake Gurfein, Tiffany Barsotti, Gaétan Chevalier, Paul J. Mills, David Muehsam
Further research under carefully controlled conditions may shed light upon those aspects of biology which most clearly exhibit these remarkable sensitivities to low-energy influences. This would require the development of more sensitive instruments and experimental protocols designed to filter or clarify the effects of interfering factors. Methodological and logistical aspects, for example, would include: the development of instruments sensitive enough to measure biofields or low-energy interactions; specialized equipment and laboratories, including the use of Faraday cages, μ-metal enclosures, completely dark rooms, anechoic chambers, noiseproofing, etc. One step with relevance to a significant portion of cellular biology research is the careful assessment of all EMF exposure conditions, accounting for the fact that nearly all cell culture incubators produce a nonuniform EMF of a strength that has been clearly shown to produce cellular effects [84,318]. The picoTesla (pT) to nanoTesla (nT) EMF effects summarized above may be more difficult to control completely, as shielding for these extremely low field strengths may be technically difficult or impossible in some situations. These difficulties could indeed suggest that a new paradigm of research may be required wherein the naturally occurring extremely weak EMFs due to solar/geomagnetic and other ambient sources are considered as an integral part of the experimental environment. Along these lines, considering the potential for effects due to circadian and other natural rhythms may also be necessary.
Take Notice
Published in Rose Cull, Daniel Cull, Museums and Well-being, 2023
Amongst the most famous auditory works of art was produced by the artist and composer John Cage, with his work 4’33”, sometimes referred to as Sonic Zazen.32 This piece is explicitly about Taking Notice, but does not require the use of sight. In 1952 the pianist David Tudor performed this piece at the Maverick Concert Hall, taking the stage and making no sound other than the movements of the piano lid. There is a general misunderstanding about the work 4’33”, it is often erroneously referred to as a silent piece, but it was in fact the impossibility of silence that led to its composition. After John Cage spent time in Harvard University’s anechoic chamber, a room designed to absorb all sound, he had expected to hear nothing, but instead he heard sounds: his nervous system and blood flowing. “Until I die there will be sounds. And they will continue following my death. One need not fear about the future of music.”33 In the Maverick Hall, and elsewhere where the piece was performed, there were sounds too. Cage describes hearing the wind outside, the rain on the roof, people chattering, confused and increasingly annoyed, even walking out.34 The world is full of sounds. In mindfulness practice we often begin with a mindfulness of sound, especially if participants have anxiety, as it gets one to be mindful of things outside the body, before we move to the body and breath. Being involved in a performance of this piece on the centenary of John Cage’s birth, we can attest that audiences’ responses haven’t changed dramatically. Amusingly in 2011 an online campaign sought to vote on the UK’s Christmas Number One song and keep the X Factor winner from the top spot. The piece has been the recipient of “all kinds of official foolishness: one recording on YouTube has had its audio disabled for copyright infringement.”35
Evaluation of the NAL Dynamic Conversations Test in older listeners with hearing loss
Published in International Journal of Audiology, 2018
Virginia Best, Gitte Keidser, Katrina Freeston, Jörg M. Buchholz
Testing took place in a large anechoic chamber fitted with a spherical loudspeaker array. The loudspeaker array was used to simulate a virtual room which incorporated the target speech materials (monologues and conversations) as well as a background of competing conversations. The target talkers (one, two or three) were assigned randomly to three target locations (−67.5°, 0°, or +67.5° azimuth), and LEDs on top of the relevant loudspeakers indicated which one was currently active. The background scene contained 14 masker talkers, distributed around the listener at different locations in the virtual room. They were arranged in seven two-talker pairs, with the two members of each pair taking turns in a conversation, such that there were seven active maskers at any moment in time. The background noise was presented at a fixed level of 65 dB SPL (measured in the centre of the array), and the target speech level was varied to adjust the SNR.
An Evaluation of the Genotoxic Effects of Electromagnetic Radiation at 900 MHz, 1800 MHz, and 2100 MHz Frequencies with a SMART Assay in Drosophila melanogaster
Published in Electromagnetic Biology and Medicine, 2021
Merve Gunes, Kayhan Ates, Burcin Yalcin, Sibel Akkurt, Sukru Ozen, Bulent Kaya
The exposure system is depicted in Figure 1. The experiments were carried out in an anechoic chamber which has internal dimensions of 7 meters × 3.8 meters × 4 meters and which is covered inside with microwave absorbers. A styrofoam carousel holder was used to hold the Drosophila larvae-filled pyrex tube. An RF signal generator emitting the electromagnetic field for each operating frequency was used. A signal generator was placed on a wooden table which was outside of the anechoic chamber. A monopole antenna, fed by a signal generator, was placed inside at the middle point of the styrofoam holder to radiate the electromagnetic field uniformly. The connection between the signal generator and the antenna was made with coaxial cable.
Possible effects of different doses of 2.1 GHz electromagnetic radiation on learning, and hippocampal levels of cholinergic biomarkers in Wistar rats
Published in Electromagnetic Biology and Medicine, 2021
Çiğdem Gökçek-Saraç, Güven Akçay, Serdar Karakurt, Kayhan Ateş, Şükrü Özen, Narin Derin
The exposure system was presented in Figure 1. The entire carousel was placed on the anechoic chamber in the shielded room to prevent other disturbance sources. Each rat was restrained in a radially positioned tube with their snouts that were located at a distance of 8 cm (d1) and 4 cm (d2) away from the monopole antenna (Figure 1). The coaxial cable has been used to provide a connection between the RF generator and the antenna. In the experimental setup, the electric-field strengths measured by EMR300 with appropriate probe (Narda, Germany) in the “signal-on” condition have been recorded as 45 V/m and 65 V/m for d1 and d2, respectively.