395 shared publications
Department of Chemistry, University of Toronto, 80 Saint George St., Toronto, Ontario M5S3H6, Canada
373 shared publications
School of Chemical Engineering and Analytical Science, University of Manchester, Manchester M13 9PL, U.K.
265 shared publications
Department of Geography, University of Sheffield
218 shared publications
Department of Sports Medicine; Australian Institute of Sport; Bruce ACT Australia
169 shared publications
Smart Materials and Surfaces Laboratory, Faculty of Engineering & Environment, Northumbria University, Ellison Place, Newcastle upon Tyne NE1 8ST, United Kingdom
(1939 - 2018)
The control electronics for low field pulsed NMR systems, commonly referred to as the console, are designed to be wide band and highly programmable. The process of making spin lattice relaxation time (T1) measurements with such a pulsed system usually use recovery sequences that will typically take many minutes to give a single T1 value. A simple transient effect method for the determination of the spin-lattice relaxation time using continuous wave NMR with a marginal oscillator, known as TEDSpiL, was recently reported (doi:10.1002/mrc.4594). Such a system measures a parameter, called Tx, that is related to T1 and allows T1 to be determined with the aid of calibration samples. For such a system, the process of making the Tx measurement only takes a few seconds and does not require variable parameters so is ideal for implementing in microcontroller code. In this presentation, we demonstrate that TEDSpiL may be automated using two microcontrollers from the Teensy family. One microcontroller is used to generate a magnetic field sweep voltage and a trigger pulse for the second microcontroller that is used to record the data and calculate the value of Tx. Whilst the Tx value is not a direct equivalent for T1, there are applications where such a method may provide a suitable cost effective, low power and portable measurement technique.
The use of accelerometers to obtain information on the state of honeybee colonies has several advantages over sound recorded by microphones, in that (i) accelerometers can reside in a honeybee hive for several years with a negligible effect of propolis coating (ii) they are particularly good at monitoring the low frequency signals which form a large part of the honeybee communication processes, and (iii) they sense a physical property, the vibration, that is probably far more relevant to them than sounds. One example of accelerometers allowing the observation of specific vibrational communication signals has been reported for the ‘whooping signal’ (doi: 10.1371/journal.pone.0171162). The vibrational amplitude is also dependent on the local environment/substrate and this has been demonstrated to be a strong indicator of an active queen (doi:10.1371/journal.pone.0141926). These previous reports have used ultra-high performance accelerometers (Brüel and Kjær, 4507) which also require separate signal conditioning electronics before the vibrational data can be logged; this represents a very expensive arrangement that precludes wide deployment. In this work we demonstrate that the 805M1 single axis analogue output accelerometer, that incorporates a piezo-ceramic crystal with low power electronics in a shielded housing, can be used to monitor honey bee activity and requires only a low cost microcontroller with an audio shield to log the data. We present high quality accelerometer output signals for both individual bee pulses and long term amplitude monitoring using this affordable measurement system. The signals appear of similar quality to those acquired with ten fold more expensive equipment.