title: A marine isotope stage 11 coastal Acheulian workshop with associated wood at Amanzi Springs Area 1, South Africa

authors: Herries, Andy I. R.

subjects: South Africa

abstract: Amanzi Springs is a series of inactive thermal springs located near Kariega in the Eastern Cape of South Africa. Excavations in the 1960s exposed rare, stratified Acheulian-bearing deposits that were not further investigated over the next 50 years. Reanalysis of the site and its legacy collection has led to a redefined stratigraphic context for the archaeology, a confirmed direct association between Acheulian artefacts and wood, as well as the first reliable age estimates for the site. Thermally transferred optically stimulated luminescence and post-infrared infrared stimulated luminescence dating indicates that the Acheulian deposits from the Amanzi Springs Area 1 spring eye formed during Marine Isotope Stage (MIS) 11 at ~ 404-390 ka. At this time, higher sea levels of ~13-14m would have placed Amanzi Springs around 7 km from a ria that would have formed along what is today the Swartkops River, and which likely led to spring reactivation. This makes the Amanzi Springs Area 1 assemblage an unusual occurrence of a verified late occurring, seaward, open-air Acheulian occupation. The Acheulian levels do not contain any Middle Stone Age (MSA) elements such as blades and points that have been documented in the interior of South Africa at this time. However, a small number of stone tools from the upper layers of the artefact zone, and originally thought of as intrusive, have been dated to ~190 ka, at the transition between MIS 7 to 6, and represent the first potential MSA identified at the site.

text: A marine isotope stage 11 coastal Acheulian workshop with associated wood at Amanzi Springs Area 1, South Africa Amanzi Springs is a series of inactive thermal springs located near Kariega in the Eastern Cape of South Africa. Excavations in the 1960s exposed rare, stratified Acheulian-bearing deposits that were not further investigated over the next 50 years. Reanalysis of the site and its legacy collection has led to a redefined stratigraphic context for the archaeology, a confirmed direct association between Acheulian artefacts and wood, as well as the first reliable age estimates for the site. Thermally transferred optically stimulated luminescence and post-infrared infrared stimulated luminescence dating indicates that the Acheulian deposits from the Amanzi Springs Area 1 spring eye formed during Marine Isotope Stage (MIS) 11 at ~ 404-390 ka. At this time, higher sea levels of ~13-14m would have placed Amanzi Springs around 7 km from a ria that would have formed along what is today the Swartkops River, and which likely led to spring reactivation. This makes the Amanzi Springs Area 1 assemblage an unusual occurrence of a verified late occurring, seaward, open-air Acheulian occupation. The Acheulian levels do not contain any Middle Stone Age (MSA) elements such as blades and points that have been documented in the interior of South Africa at this time. However, a small number of stone tools from the upper layers of the artefact zone, and originally thought of as intrusive, have been dated to ~190 ka, at the transition between MIS 7 to 6, and represent the first potential MSA identified at the site.

year: 2022-10-20

title: Cause and Amelioration of MRI-Induced Heating Through Medical Implant Lead Wires

authors: McCabe, Steven Owen

abstract: The RF fields present in magnetic resonance imaging (MRI) scanners can induce hazardous heating in patients wearing medical implants. The inherent design and locale of deep brain stimulators (DBS) and spinal cord stimulators (SCS) make them particularly susceptible. We apply antenna concepts and use electromagnetic (EM) simulation to explain the phenomenon and anticipate its sensitivity to lead wire length. We anticipate that a DC resistance of less than 50 Ω/m and an RF impedance of more than 1:23kΩ/m would be required for a safe electrode for SCS use. We investigate the possibility of manipulating wire conductivity and diameter in order to use the skin depth effect to achieve a safe electrode. The effect of the thickness and permittivity of insulation surrounding the wires is explored.

text: Cause and Amelioration of MRI-Induced Heating Through Medical Implant Lead Wires The RF fields present in magnetic resonance imaging (MRI) scanners can induce hazardous heating in patients wearing medical implants. The inherent design and locale of deep brain stimulators (DBS) and spinal cord stimulators (SCS) make them particularly susceptible. We apply antenna concepts and use electromagnetic (EM) simulation to explain the phenomenon and anticipate its sensitivity to lead wire length. We anticipate that a DC resistance of less than 50 Ω/m and an RF impedance of more than 1:23kΩ/m would be required for a safe electrode for SCS use. We investigate the possibility of manipulating wire conductivity and diameter in order to use the skin depth effect to achieve a safe electrode. The effect of the thickness and permittivity of insulation surrounding the wires is explored.

year: 2014

title: Te Pae Mahutonga and the measurement of community capital in regional Aotearoa New Zealand

authors: Ryks, John

abstract: Regionally, iwi and hapū have limited influence over structural changes such as population decline, proximity to labour markets and ageing, and to some extent economic cycles. However, there is still considerable value in thinking about how relevant indicators might point to the regeneration and overall well-being of Māori communities. In this paper we present an exploratory framework that links Durie’s Te Pae Mahutonga model of Māori well-being to the measurement of community capital. We use Te Pae Mahutonga as the basis for developing a number of key indicators for understanding Māori well-being in the regions and apply the framework and indicators to three regional settlements in Aotearoa New Zealand: Pōkeno, Huntly and Ōpōtiki.

text: Te Pae Mahutonga and the measurement of community capital in regional Aotearoa New Zealand Regionally, iwi and hapū have limited influence over structural changes such as population decline, proximity to labour markets and ageing, and to some extent economic cycles. However, there is still considerable value in thinking about how relevant indicators might point to the regeneration and overall well-being of Māori communities. In this paper we present an exploratory framework that links Durie’s Te Pae Mahutonga model of Māori well-being to the measurement of community capital. We use Te Pae Mahutonga as the basis for developing a number of key indicators for understanding Māori well-being in the regions and apply the framework and indicators to three regional settlements in Aotearoa New Zealand: Pōkeno, Huntly and Ōpōtiki.

year: 2018