title: Evaluation of detector material and radiation source position on Compton camera’s ability for multitracer imaging

authors: Uche, Chibueze Zimuzo

subjects: Compton camera

abstract: We present a study on the effects of detector material, radionuclide source and source position on the Compton camera aimed at realistic characterization of the camera's performance in multitracer imaging as it relates to brain imaging. The GEANT4 Monte Carlo simulation software was used to model the physics of radiation transport and interactions with matter. Silicon (Si) and germanium (Ge) detectors were evaluated for the scatterer, and cadmium zinc telluride (CZT) and cerium-doped lanthanum bromide (LaBr3:Ce) were considered for the absorber. Image quality analyses suggest that the use of Si as the scatterer and CZT as the absorber would be preferred. Nevertheless, two simulated Compton camera models (Si/CZT and Si/LaBr3:Ce Compton cameras) that are considered in this study demonstrated good capabilities for multitracer imaging in that four radiotracers within the nuclear medicine energy range are clearly visualized by the cameras. It is found however that beyond a range difference of about 2 cm for In-113m and F-18 radiotracers in a brain phantom, there may be a need to rotate the Compton camera for efficient brain imaging.

text: Evaluation of detector material and radiation source position on Compton camera’s ability for multitracer imaging We present a study on the effects of detector material, radionuclide source and source position on the Compton camera aimed at realistic characterization of the camera's performance in multitracer imaging as it relates to brain imaging. The GEANT4 Monte Carlo simulation software was used to model the physics of radiation transport and interactions with matter. Silicon (Si) and germanium (Ge) detectors were evaluated for the scatterer, and cadmium zinc telluride (CZT) and cerium-doped lanthanum bromide (LaBr3:Ce) were considered for the absorber. Image quality analyses suggest that the use of Si as the scatterer and CZT as the absorber would be preferred. Nevertheless, two simulated Compton camera models (Si/CZT and Si/LaBr3:Ce Compton cameras) that are considered in this study demonstrated good capabilities for multitracer imaging in that four radiotracers within the nuclear medicine energy range are clearly visualized by the cameras. It is found however that beyond a range difference of about 2 cm for In-113m and F-18 radiotracers in a brain phantom, there may be a need to rotate the Compton camera for efficient brain imaging.

year: 2012

title: Book review: Shift

authors: Locke, Terry

subjects: review

abstract: The article reviews the book "Shift," by Rhian Gallagher.

text: Book review: Shift The article reviews the book "Shift," by Rhian Gallagher.

year: 2011

title: Te whakahaumanu i ngā taonga takatāpui: Belonging and thrivance for takatāpui

authors: Ngātai-Tautuku, Te Aorere

subjects: takatāpui

abstract: This thesis celebrates takatāpui belonging and thrivance; created by, with and for takatāpui. It is carefully crafted with an abundance of love for this community to which I belong. Informed by the overarching conceptual framework of Te Pū o te Rākau (pūrākau) methodology (Lee-Morgan, 2019), this thesis follows pūrākau of how takatāpui and queer Māori identify and express belonging and thrivance. The intention of this study is to privilege the voices and lived experiences of people who have been consistently subject to the systematic dehumanisation of Western research conventions.

In the aftermath of the COVID-19 pandemic in 2020, anti-Māori racism, homophobia and transphobia have risen exponentially in Aotearoa, spurring an increase in aggressive violent attacks on marginalised communities. It is progressively evident that the fundamental right to tino rangatiratanga affirmed by Te Tiriti o Waitangi to express self-determination has failed to be honoured (Came et al., 2024; Mutu, 2011a). Therefore, it is paramount within this rangahau to give power to and centralise the voices of takatāpui as they express their experiences of belonging. 

Drawing upon the springs of mātauranga takatāpui  (re)generated by takatāpui academics, this rangahau is firmly grounded within a takatāpui worldview. Adapted elements from Te Pū o te Rākau methodological framework are implemented in this rangahau to (re)affirm the importance of takatāpui voices and interdependent relationships. Experienced through the ritualistic ceremony of wānanga, informed by Kaupapa Māori tenet - titiro, whakarongo… kōrero – I facilitated a wānanga for a group of kaipūrākau to share their pūrākau at Te Kohinga Mārama marae. Throughout the wānanga the kaipūrākau shared hilarious, heartwarming and painful pūrākau about their lived experiences as Indigenous queer people navigating a settler-colonial Western society and their encounters with belonging. These precious pūrākau are then translated into key themes that communicate the findings of this rangahau, that are described as Whanaungatanga, Tuakiritanga, Mana Motuhake and Te Hari Te Koa.

text: Te whakahaumanu i ngā taonga takatāpui: Belonging and thrivance for takatāpui This thesis celebrates takatāpui belonging and thrivance; created by, with and for takatāpui. It is carefully crafted with an abundance of love for this community to which I belong. Informed by the overarching conceptual framework of Te Pū o te Rākau (pūrākau) methodology (Lee-Morgan, 2019), this thesis follows pūrākau of how takatāpui and queer Māori identify and express belonging and thrivance. The intention of this study is to privilege the voices and lived experiences of people who have been consistently subject to the systematic dehumanisation of Western research conventions.

In the aftermath of the COVID-19 pandemic in 2020, anti-Māori racism, homophobia and transphobia have risen exponentially in Aotearoa, spurring an increase in aggressive violent attacks on marginalised communities. It is progressively evident that the fundamental right to tino rangatiratanga affirmed by Te Tiriti o Waitangi to express self-determination has failed to be honoured (Came et al., 2024; Mutu, 2011a). Therefore, it is paramount within this rangahau to give power to and centralise the voices of takatāpui as they express their experiences of belonging. 

Drawing upon the springs of mātauranga takatāpui  (re)generated by takatāpui academics, this rangahau is firmly grounded within a takatāpui worldview. Adapted elements from Te Pū o te Rākau methodological framework are implemented in this rangahau to (re)affirm the importance of takatāpui voices and interdependent relationships. Experienced through the ritualistic ceremony of wānanga, informed by Kaupapa Māori tenet - titiro, whakarongo… kōrero – I facilitated a wānanga for a group of kaipūrākau to share their pūrākau at Te Kohinga Mārama marae. Throughout the wānanga the kaipūrākau shared hilarious, heartwarming and painful pūrākau about their lived experiences as Indigenous queer people navigating a settler-colonial Western society and their encounters with belonging. These precious pūrākau are then translated into key themes that communicate the findings of this rangahau, that are described as Whanaungatanga, Tuakiritanga, Mana Motuhake and Te Hari Te Koa.

year: 2025-06-19