title: Range imager performance comparison in homodyne and heterodyne operating modes

authors: Conroy, Richard M.

subjects: three-dimensional

abstract: Range imaging cameras measure depth simultaneously for every pixel in a given field of view. In most implementations the basic operating principles are the same. A scene is illuminated with an intensity modulated light source and the reflected signal is sampled using a gain-modulated imager. Previously we presented a unique heterodyne range imaging system that employed a bulky and power hungry image intensifier as the high speed gain-modulation mechanism. In this paper we present a new range imager using an internally modulated image sensor that is designed to operate in heterodyne mode, but can also operate in homodyne mode. We discuss homodyne and heterodyne range imaging, and the merits of the various types of hardware used to implement these systems. Following this we describe in detail the hardware and firmware components of our new ranger. We experimentally compare the two operating modes and demonstrate that heterodyne operation is less sensitive to some of the limitations suffered in homodyne mode, resulting in better linearity and ranging precision characteristics. We conclude by showing various qualitative examples that demonstrate the system’s three-dimensional measurement performance.

text: Range imager performance comparison in homodyne and heterodyne operating modes Range imaging cameras measure depth simultaneously for every pixel in a given field of view. In most implementations the basic operating principles are the same. A scene is illuminated with an intensity modulated light source and the reflected signal is sampled using a gain-modulated imager. Previously we presented a unique heterodyne range imaging system that employed a bulky and power hungry image intensifier as the high speed gain-modulation mechanism. In this paper we present a new range imager using an internally modulated image sensor that is designed to operate in heterodyne mode, but can also operate in homodyne mode. We discuss homodyne and heterodyne range imaging, and the merits of the various types of hardware used to implement these systems. Following this we describe in detail the hardware and firmware components of our new ranger. We experimentally compare the two operating modes and demonstrate that heterodyne operation is less sensitive to some of the limitations suffered in homodyne mode, resulting in better linearity and ranging precision characteristics. We conclude by showing various qualitative examples that demonstrate the system’s three-dimensional measurement performance.

year: 2009

title: Structural and functional characterization of a promiscuous feruloyl esterase (Est1E) from the rumen bacterium Butyrivibrio proteoclasticus

authors: Goldston, David C.

subjects: rumen

abstract: The release of polysaccharide from the plant cell wall is a key process to release the stored energy from plant biomass. Within the ruminant digestive system, a host of commensal microorganisms speed the breakdown of plant cell matter releasing fermentable sugars. The presence of phenolic compounds, most notably ferulic acid (FA), esterified within the cell wall is thought to pose a significant impediment to the degradation of the plant cell wall. The structure of a FA esterase from the ruminant bacterium Butyrivibrio proteoclasticus has been determined in two different space groups, in both the apo-form, and the ligand bound form with FA located in the active site. The structure reveals a new lid domain that has no structural homologues in the PDB. The flexibility of the lid domain is evident by the presence of three different conformations adopted by different molecules in the crystals. In the FA-bound structures, these conformations show sequential binding and closing of the lid domain over the substrate. Enzymatic activity assays demonstrate a broad activity against plant-derived hemicellulose, releasing at least four aromatic compounds including FA, coumaric acid, coumarin-3-carboxylic acid, and cinnamic acid. The rumen is a complex ecosystem that efficiently degrades plant biomass and the genome of B. proteoclasticus contains greater than 130 enzymes, which are potentially involved in this process of which Est1E is the first to be well characterized.

text: Structural and functional characterization of a promiscuous feruloyl esterase (Est1E) from the rumen bacterium Butyrivibrio proteoclasticus The release of polysaccharide from the plant cell wall is a key process to release the stored energy from plant biomass. Within the ruminant digestive system, a host of commensal microorganisms speed the breakdown of plant cell matter releasing fermentable sugars. The presence of phenolic compounds, most notably ferulic acid (FA), esterified within the cell wall is thought to pose a significant impediment to the degradation of the plant cell wall. The structure of a FA esterase from the ruminant bacterium Butyrivibrio proteoclasticus has been determined in two different space groups, in both the apo-form, and the ligand bound form with FA located in the active site. The structure reveals a new lid domain that has no structural homologues in the PDB. The flexibility of the lid domain is evident by the presence of three different conformations adopted by different molecules in the crystals. In the FA-bound structures, these conformations show sequential binding and closing of the lid domain over the substrate. Enzymatic activity assays demonstrate a broad activity against plant-derived hemicellulose, releasing at least four aromatic compounds including FA, coumaric acid, coumarin-3-carboxylic acid, and cinnamic acid. The rumen is a complex ecosystem that efficiently degrades plant biomass and the genome of B. proteoclasticus contains greater than 130 enzymes, which are potentially involved in this process of which Est1E is the first to be well characterized.

year: 2010

title: Whānau Stories: Creating meaningful engagement and wellbeing for the indigenous culture of Aotearoa New Zealand

authors: Cruse, Diana Caroline Annavale

subjects: Engagement

abstract: This research sees my interests coalesce into a particular focus on how collaborative partnerships with parents/caregivers can provide whānau Māori with opportunities to strengthen wellbeing in their own lives. It is located in Aotearoa New Zealand and within the context of Te Whāriki (Ministry of Education, 1996), Aotearoa New Zealand’s early childhood curriculum.  The Ministry of Education has a target that 98% of all children in Aotearoa New Zealand under 5 will attend an early childhood education setting (Ministry of Education, 2016), with Māori children having lower participation rates than the national participation rate (Ministry of Education, 2013).  The premise for this thesis is that meaningful whānau engagement in early learning contexts within Aotearoa New Zealand can empower whānau Māori, and honour the promises made in Te Tiriti o Waitangi of partnership, participation, and protection.
Therefore, this thesis sets out to examine what constitutes meaningful engagement for whānau Māori in an early childhood setting in Aotearoa New Zealand, and how meaningful engagement can assist whānau to enjoy an increase of wellbeing.
To explore this issue, I conducted research within an early childhood setting in Aotearoa New Zealand, using methodologies of Kaupapa Māori Research and Narrative Inquiry.  I listened to the narratives of whānau Māori indicating how meaningful engagement was created for them, and investigated if links were generated between engagement and wellbeing for their whānau. These links were identified in the literature as significant levers for educational success.
This research discovered three stages of engagement for the whānau Māori who participated in this study: establishing engagement, developing engagement and solidifying engagement.  Once created, meaningful engagement can lead to flourishing, indicating that there is relationship between meaningful engagement and whānau wellbeing.

text: Whānau Stories: Creating meaningful engagement and wellbeing for the indigenous culture of Aotearoa New Zealand This research sees my interests coalesce into a particular focus on how collaborative partnerships with parents/caregivers can provide whānau Māori with opportunities to strengthen wellbeing in their own lives. It is located in Aotearoa New Zealand and within the context of Te Whāriki (Ministry of Education, 1996), Aotearoa New Zealand’s early childhood curriculum.  The Ministry of Education has a target that 98% of all children in Aotearoa New Zealand under 5 will attend an early childhood education setting (Ministry of Education, 2016), with Māori children having lower participation rates than the national participation rate (Ministry of Education, 2013).  The premise for this thesis is that meaningful whānau engagement in early learning contexts within Aotearoa New Zealand can empower whānau Māori, and honour the promises made in Te Tiriti o Waitangi of partnership, participation, and protection.
Therefore, this thesis sets out to examine what constitutes meaningful engagement for whānau Māori in an early childhood setting in Aotearoa New Zealand, and how meaningful engagement can assist whānau to enjoy an increase of wellbeing.
To explore this issue, I conducted research within an early childhood setting in Aotearoa New Zealand, using methodologies of Kaupapa Māori Research and Narrative Inquiry.  I listened to the narratives of whānau Māori indicating how meaningful engagement was created for them, and investigated if links were generated between engagement and wellbeing for their whānau. These links were identified in the literature as significant levers for educational success.
This research discovered three stages of engagement for the whānau Māori who participated in this study: establishing engagement, developing engagement and solidifying engagement.  Once created, meaningful engagement can lead to flourishing, indicating that there is relationship between meaningful engagement and whānau wellbeing.

year: 2017