title: Characteristics of temporal fluctuations in the hyperpolarized state of the cortical slow oscillation

authors: Wilson, Marcus T.

subjects: bioelectric potentials

abstract: We present evidence for the hypothesis that transitions between the low- and high-firing states of the cortical slow oscillation correspond to neuronal phase transitions. By analyzing intracellular recordings of the membrane potential during the cortical slow oscillation in rats, we quantify the temporal fluctuations in power and the frequency centroid of the power spectrum in the period of time before “down” to “up” transitions. By taking appropriate averages over such events, we present these statistics as a function of time before transition. The results demonstrate an increase in fluctuation power and time scale broadly consistent with the slowing of systems close to phase transitions. The analysis is complicated and limited by the difficulty in identifying when transitions begin, and removing dc trends in membrane potential.

text: Characteristics of temporal fluctuations in the hyperpolarized state of the cortical slow oscillation We present evidence for the hypothesis that transitions between the low- and high-firing states of the cortical slow oscillation correspond to neuronal phase transitions. By analyzing intracellular recordings of the membrane potential during the cortical slow oscillation in rats, we quantify the temporal fluctuations in power and the frequency centroid of the power spectrum in the period of time before “down” to “up” transitions. By taking appropriate averages over such events, we present these statistics as a function of time before transition. The results demonstrate an increase in fluctuation power and time scale broadly consistent with the slowing of systems close to phase transitions. The analysis is complicated and limited by the difficulty in identifying when transitions begin, and removing dc trends in membrane potential.

year: 2008

title: Micro-eukaryotic diversity in hypolithons from Miers Valley, Antarctica

authors: Gokul, Jarishma K.

subjects: Antarctica

abstract: The discovery of extensive and complex hypolithic communities in both cold and hot deserts has raised many questions regarding their ecology, biodiversity and relevance in terms of regional productivity. However, most hypolithic research has focused on the bacterial elements of the community. This study represents the first investigation of micro-eukaryotic communities in all three hypolith types. Here we show that Antarctic hypoliths support extensive populations of novel uncharacterized bryophyta, fungi and protists and suggest that well known producer-decomposer-predator interactions may create the necessary conditions for hypolithic productivity in Antarctic deserts.

text: Micro-eukaryotic diversity in hypolithons from Miers Valley, Antarctica The discovery of extensive and complex hypolithic communities in both cold and hot deserts has raised many questions regarding their ecology, biodiversity and relevance in terms of regional productivity. However, most hypolithic research has focused on the bacterial elements of the community. This study represents the first investigation of micro-eukaryotic communities in all three hypolith types. Here we show that Antarctic hypoliths support extensive populations of novel uncharacterized bryophyta, fungi and protists and suggest that well known producer-decomposer-predator interactions may create the necessary conditions for hypolithic productivity in Antarctic deserts.

year: 2013-02-22

title: "Ko au te whenua, ko te whenua ko au:" A Māori housing development process

authors: Fletcher, Marcus Anzac Kewene

subjects: Māori

abstract: Tangata whenua (People of the land/Indigenous people of Aotearoa) are being recognised as emerging property and land developers in Aotearoa New Zealand (hereafter, Aotearoa). Literature and practice demonstrates how Māori are developing housing in different ways than traditional developers, supporting the wellbeing of whānau (families), hapū (sub-tribes) and iwi (tribes), while contributing to addressing the national housing crisis. The distinctiveness of these approaches are important to understand if we want to deepen our knowledge of urban development and the modelling of housing markets in Aotearoa. This thesis aims to reveal, codify and examine Māori decision-making processes relating to how and why we develop housing in Aotearoa and the values and principles that inform these approaches. Utilising Kaupapa Māori Theory and taking an insider/whānaunga (relatives) approach to the research, four whakawhiti kōrero sessions with Waikato whānau and kaimahi (workers) were undertaken to better understand how and why Māori develop housing and the processes and rationalities at play. The thesis has three contributions for academia, environmental planning and the housing sector in Aotearoa: insights into the values and rationalities that influence Māori urban development; the introduction of a Māori housing development framework; and insights into how the framework may be utilised to contribute towards more accurate and sophisticated agent-based modelling (ABM) or urban growth modelling.  

The findings and discussion identified six prominent values that Māori utilise to develop housing: kaitiakitanga, manaakitanga, orangatanga, whānaungatanga, ūkaipōtanga and rangatiratanga. Being rooted in Māori knowledge and epistemology essentially demands differing rationalities for when Māori undertake housing development, which are placed within an overarching framework. The framework represents a new tool to disrupt the current understanding of ‘developers’ as a single entity with a defined pathway that influences all development behaviour. Moreover, it demonstrates how whānau, hapū and iwi draw on the established learning and guidance of our tūpuna (ancestors) and the strides taken to reclaim tino rangatiratanga (self-determination). The thesis argues that academics, environmental practitioners and the housing sector should re-examine their understanding of developers in Aotearoa to become more pluralistic, which may present new challenges and opportunities for ABM and urban growth modelling. This framework argues some aspects may have potential to be incorporated into these technical analyses, while other aspects should be considered in the context of Māori and Indigenous Data Sovereignty to protect the contributions and mana of the participants within this thesis, or resist the ability to be captured altogether.

text: "Ko au te whenua, ko te whenua ko au:" A Māori housing development process Tangata whenua (People of the land/Indigenous people of Aotearoa) are being recognised as emerging property and land developers in Aotearoa New Zealand (hereafter, Aotearoa). Literature and practice demonstrates how Māori are developing housing in different ways than traditional developers, supporting the wellbeing of whānau (families), hapū (sub-tribes) and iwi (tribes), while contributing to addressing the national housing crisis. The distinctiveness of these approaches are important to understand if we want to deepen our knowledge of urban development and the modelling of housing markets in Aotearoa. This thesis aims to reveal, codify and examine Māori decision-making processes relating to how and why we develop housing in Aotearoa and the values and principles that inform these approaches. Utilising Kaupapa Māori Theory and taking an insider/whānaunga (relatives) approach to the research, four whakawhiti kōrero sessions with Waikato whānau and kaimahi (workers) were undertaken to better understand how and why Māori develop housing and the processes and rationalities at play. The thesis has three contributions for academia, environmental planning and the housing sector in Aotearoa: insights into the values and rationalities that influence Māori urban development; the introduction of a Māori housing development framework; and insights into how the framework may be utilised to contribute towards more accurate and sophisticated agent-based modelling (ABM) or urban growth modelling.  

The findings and discussion identified six prominent values that Māori utilise to develop housing: kaitiakitanga, manaakitanga, orangatanga, whānaungatanga, ūkaipōtanga and rangatiratanga. Being rooted in Māori knowledge and epistemology essentially demands differing rationalities for when Māori undertake housing development, which are placed within an overarching framework. The framework represents a new tool to disrupt the current understanding of ‘developers’ as a single entity with a defined pathway that influences all development behaviour. Moreover, it demonstrates how whānau, hapū and iwi draw on the established learning and guidance of our tūpuna (ancestors) and the strides taken to reclaim tino rangatiratanga (self-determination). The thesis argues that academics, environmental practitioners and the housing sector should re-examine their understanding of developers in Aotearoa to become more pluralistic, which may present new challenges and opportunities for ABM and urban growth modelling. This framework argues some aspects may have potential to be incorporated into these technical analyses, while other aspects should be considered in the context of Māori and Indigenous Data Sovereignty to protect the contributions and mana of the participants within this thesis, or resist the ability to be captured altogether.

year: 2025