title: A Novel Implant Electrode Design Safe in the RF Field of MRI Scanners

authors: McCabe, Steven Owen

abstract: Patients with medical implants are often unable to receive magnetic resonance imaging (MRI) diagnostic treatment, because the conductive leads can concentrate the RF excitation field and generate dangerous heating of nervous tissue. We propose a simple, low-cost solution that minimizes RF heating through the addition of one or more mutually coupled filars to the lead without significant increase in lead diameter. Simulations and measurements at 128 MHz are presented to verify the effect in 3 T MRI machines.

text: A Novel Implant Electrode Design Safe in the RF Field of MRI Scanners Patients with medical implants are often unable to receive magnetic resonance imaging (MRI) diagnostic treatment, because the conductive leads can concentrate the RF excitation field and generate dangerous heating of nervous tissue. We propose a simple, low-cost solution that minimizes RF heating through the addition of one or more mutually coupled filars to the lead without significant increase in lead diameter. Simulations and measurements at 128 MHz are presented to verify the effect in 3 T MRI machines.

year: 2017

title: Distribution and abundance of fish and crayfish in a Waikato stream in relation to basin area

authors: Hicks, Brendan J.

subjects: native fish

abstract: The aim of this study was to relate the longitudinal distribution of fish and crayfish to increasing basin area and physical site characteristics in the Mangaotama Stream, Waikato region, North Island, New Zealand. Fish and crayfish were captured with two-pass removal electroshocking at 11 sites located in hill-country with pasture, native forest, and mixed land uses within the 21.6 km2 basin. Number of fish species and lineal biomass of fish increased with increasing basin area, but barriers to upstream fish migration also influenced fish distribution; only climbing and non-migratory species were present above a series of small waterfalls. Fish biomass increased in direct proportion to stream width, suggesting that fish used much of the available channel, and stream width was closely related to basin area. Conversely, the abundance of crayfish was related to the amount of edge habitat, and therefore crayfish did not increase in abundance as basin area increased. Densities of all fish species combined ranged from 17 to 459 fish 100 m-2, and biomass ranged from 14 to 206 g m-2. Eels dominated the fish assemblages, comprising 85-100% of the total biomass; longfinned eels the majority of the biomass at most sites. Despite the open access of the lower sites to introduced brown trout, native species dominated all the fish communities sampled.

text: Distribution and abundance of fish and crayfish in a Waikato stream in relation to basin area The aim of this study was to relate the longitudinal distribution of fish and crayfish to increasing basin area and physical site characteristics in the Mangaotama Stream, Waikato region, North Island, New Zealand. Fish and crayfish were captured with two-pass removal electroshocking at 11 sites located in hill-country with pasture, native forest, and mixed land uses within the 21.6 km2 basin. Number of fish species and lineal biomass of fish increased with increasing basin area, but barriers to upstream fish migration also influenced fish distribution; only climbing and non-migratory species were present above a series of small waterfalls. Fish biomass increased in direct proportion to stream width, suggesting that fish used much of the available channel, and stream width was closely related to basin area. Conversely, the abundance of crayfish was related to the amount of edge habitat, and therefore crayfish did not increase in abundance as basin area increased. Densities of all fish species combined ranged from 17 to 459 fish 100 m-2, and biomass ranged from 14 to 206 g m-2. Eels dominated the fish assemblages, comprising 85-100% of the total biomass; longfinned eels the majority of the biomass at most sites. Despite the open access of the lower sites to introduced brown trout, native species dominated all the fish communities sampled.

year: 2003-06-01

title: The Digital Divide in New Zealand: The position of Māori and Pacific peoples

authors: Gibson, John

subjects: Māori digital access

abstract: Information and communication technology plays an ever-growing role in economic, political and social life and those who are unable to access such technologies are increasingly disadvantaged. Hence, what has come to be known as the ‘digital divide’ is of considerable significance. Here, indicators of that divide as it affects Māori and Pacific Islands peoples in Aotearoa/New Zealand are presented and discussed.

text: The Digital Divide in New Zealand: The position of Māori and Pacific peoples Information and communication technology plays an ever-growing role in economic, political and social life and those who are unable to access such technologies are increasingly disadvantaged. Hence, what has come to be known as the ‘digital divide’ is of considerable significance. Here, indicators of that divide as it affects Māori and Pacific Islands peoples in Aotearoa/New Zealand are presented and discussed.

year: 2002-09