title: Design and demonstration of a mouse-specific Transcranial Magnetic Stimulation coil in-vitro

authors: Khokhar, Farah Adeebah

abstract: In Transcranial Magnetic Stimulation, rapid electromagnetic fields (EM) are applied to the brain. The fundamental effects of TMS are poorly understood so we need smaller coils to perform invasive measurements on mice. Based on established physics principles, I have designed, built and modelled four mouse-specific TMS coils. A capacitor is discharged through these coils at 50 V power supply. The magnetic flux densities of these coils were measured with a Hall probe at the base of the coils and 2 mm above the Hall sensor. The induced electric field strengths of these coils were measured with a wire loop at 50 V power supply. The heating in coils were measured at 50 V supply with thermocouple probe.
I aimed to design and demonstrate a mouse-specific TMS coil that can generate high and focused induced electric field. I have designed, measured and modelled 50-turn tapered powdered iron core-coil that generated magnetic field strengths of around 700 mT at 0 mm above the coil and 340 mT at 2 mm above the coil. This shows that the coil is close to the B-field value of human TMS coils. These B-fields are larger than the previously designed coils by other researchers. However, while the induced E-field was focused at 10 V/m, it was still significantly lower in strength than for human TMS coils.
Finally, I have applied 1200 pulses of continuous theta burst stimulation (cTBS) and intermittent theta burst stimulation (iTBS) to mouse brain slices and analysed the change in spontaneous electrical activity and evoked potential response in mouse brain with the 50-turn tapered powdered iron-core coil. For SLE experiments, we see a significant change in SLE frequencies. For cTBS, the frequency decreases over 0–20 minutes after stimulation and for iTBS the frequency increases over 0–20 minutes after stimulation. For evoked potential experiments, we see no significant change in either peak-to-peak amplitudes or gradient responses.
In this four-year thesis project, a tapered mouse-specific TMS coil has been designed and demonstrated in vitro. The electromagnetic field strengths measured for this coil are sufficient to change the spontaneous behaviour of mouse brain slice with theta burst stimulation.

text: Design and demonstration of a mouse-specific Transcranial Magnetic Stimulation coil in-vitro In Transcranial Magnetic Stimulation, rapid electromagnetic fields (EM) are applied to the brain. The fundamental effects of TMS are poorly understood so we need smaller coils to perform invasive measurements on mice. Based on established physics principles, I have designed, built and modelled four mouse-specific TMS coils. A capacitor is discharged through these coils at 50 V power supply. The magnetic flux densities of these coils were measured with a Hall probe at the base of the coils and 2 mm above the Hall sensor. The induced electric field strengths of these coils were measured with a wire loop at 50 V power supply. The heating in coils were measured at 50 V supply with thermocouple probe.
I aimed to design and demonstrate a mouse-specific TMS coil that can generate high and focused induced electric field. I have designed, measured and modelled 50-turn tapered powdered iron core-coil that generated magnetic field strengths of around 700 mT at 0 mm above the coil and 340 mT at 2 mm above the coil. This shows that the coil is close to the B-field value of human TMS coils. These B-fields are larger than the previously designed coils by other researchers. However, while the induced E-field was focused at 10 V/m, it was still significantly lower in strength than for human TMS coils.
Finally, I have applied 1200 pulses of continuous theta burst stimulation (cTBS) and intermittent theta burst stimulation (iTBS) to mouse brain slices and analysed the change in spontaneous electrical activity and evoked potential response in mouse brain with the 50-turn tapered powdered iron-core coil. For SLE experiments, we see a significant change in SLE frequencies. For cTBS, the frequency decreases over 0–20 minutes after stimulation and for iTBS the frequency increases over 0–20 minutes after stimulation. For evoked potential experiments, we see no significant change in either peak-to-peak amplitudes or gradient responses.
In this four-year thesis project, a tapered mouse-specific TMS coil has been designed and demonstrated in vitro. The electromagnetic field strengths measured for this coil are sufficient to change the spontaneous behaviour of mouse brain slice with theta burst stimulation.

year: 2021

title: Livestock traceability in New Zealand: Using blockchain to address current challenges in the industry

authors: Deenamulle Kankanamge, Deepika Priyadarshani

subjects: Livestock traceability

abstract: The existing livestock traceability system in New Zealand hardly achieves the general goals of a traceability system such as managing disease outbreaks and tracking animal-based products from farm to fork. Further, users often complain that the New Zealand system is difficult to use. To overcome such issues in other parts of the world, blockchain-based traceability systems have been suggested. However, there is little research in the New Zealand context. This study aims to fill that gap by identifying challenges in the existing livestock traceability system in New Zealand, then evaluating if blockchain technology can address those challenges. The applicability of a blockchain-based livestock traceability system to New Zealand is discussed.
Existing literature is used to understand the potential use of blockchain technology to address livestock traceability challenges relating to the themes of data management, relationships (among supply chain partners), transparency, compliance, and visibility. To understand the New Zealand context, participants in the New Zealand livestock supply chain are interviewed. Interview data is analysed using the themes listed above. Challenges gathered from the interviews are then compared with the challenges and solutions found in literature to evaluate if a blockchain-based traceability system would suit the New Zealand context.
The results suggest that a blockchain-based traceability system supported by the Internet of Things (IoT) and smart contracts can dramatically improve the livestock traceability system in New Zealand by addressing many of the country’s traceability challenges. However, implementing such a system could initially involve a significant cost and necessitate changes to existing organisational practices. Further, workarounds should be sought for implementation barriers such as low network connectivity in rural New Zealand. Although expensive to implement, eventually, a blockchain-based traceability system could help industry manage otherwise expensive occurrences, such as food recalls, with less effort. Therefore, spending resources to implement a blockchain-based traceability system today can be a worthwhile investment for the future.

text: Livestock traceability in New Zealand: Using blockchain to address current challenges in the industry The existing livestock traceability system in New Zealand hardly achieves the general goals of a traceability system such as managing disease outbreaks and tracking animal-based products from farm to fork. Further, users often complain that the New Zealand system is difficult to use. To overcome such issues in other parts of the world, blockchain-based traceability systems have been suggested. However, there is little research in the New Zealand context. This study aims to fill that gap by identifying challenges in the existing livestock traceability system in New Zealand, then evaluating if blockchain technology can address those challenges. The applicability of a blockchain-based livestock traceability system to New Zealand is discussed.
Existing literature is used to understand the potential use of blockchain technology to address livestock traceability challenges relating to the themes of data management, relationships (among supply chain partners), transparency, compliance, and visibility. To understand the New Zealand context, participants in the New Zealand livestock supply chain are interviewed. Interview data is analysed using the themes listed above. Challenges gathered from the interviews are then compared with the challenges and solutions found in literature to evaluate if a blockchain-based traceability system would suit the New Zealand context.
The results suggest that a blockchain-based traceability system supported by the Internet of Things (IoT) and smart contracts can dramatically improve the livestock traceability system in New Zealand by addressing many of the country’s traceability challenges. However, implementing such a system could initially involve a significant cost and necessitate changes to existing organisational practices. Further, workarounds should be sought for implementation barriers such as low network connectivity in rural New Zealand. Although expensive to implement, eventually, a blockchain-based traceability system could help industry manage otherwise expensive occurrences, such as food recalls, with less effort. Therefore, spending resources to implement a blockchain-based traceability system today can be a worthwhile investment for the future.

year: 2022

title: The cost of aquatic weed control in the Rotorua Te Arawa Lakes

authors: Champion, Paul

abstract: We will present information on the costs of aquatic weed control in the Rotorua, Te Arawa Lakes and thank all of the people who have willingly given us their estimated costs. Hopefully, this provides guidance on what current activities cost and what future scenarios might be feasible.

text: The cost of aquatic weed control in the Rotorua Te Arawa Lakes We will present information on the costs of aquatic weed control in the Rotorua, Te Arawa Lakes and thank all of the people who have willingly given us their estimated costs. Hopefully, this provides guidance on what current activities cost and what future scenarios might be feasible.

year: 2017