Renewable energy technology options for Parihaka Papakāinga : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Engineering in Renewable Energy Systems at Massey University, Manawatū, New Zealand

The Parihaka Papakāinga Trust - the administering body of communally owned Māori land at Parihaka, Aotearoa New Zealand - initiated university research into sustainable energy practices and technologies within a context of community and infrastructure development. As one part of this wider research topic, various renewable energy conversion technologies were compared in terms of cost, effect on increasing the energy independence of the papakāinga (excluding transport, covered elsewhere), and reducing papakāinga greenhouse gas (GHG) emissions. Consumption of electricity, LPG and firewood was assessed in 14 study buildings over 12 months. Energy demands both now and also for hypothetical scenarios 20 years in the future were proposed, taking into account energy efficiency opportunities, low energy housing design and potential electric vehicle charging loads from parallel research. The local solar, wind and hydro potentials were assessed over 12 months, and estimations of the long-term resources were made using long-term reference data from the region. An estimation was also made of land area requirements to support a short rotation coppicing (SRC) fuelwood plantation. The technical and economic performance of a range of electricity and heat generation technologies was modelled, both on an individual building basis and on a community-wide basis. The technologies with the largest expected economic benefits (after energy efficiency and building design) were a grid-connected community solar PV array with output available for consumption by as much of the papakāinga as possible, and wood-burners for space and water heating in new homes. However further study is required into the design and costs of a feasible metering and billing solution to allocate the benefits of community owned distributed electricity generation. The technologies with the largest expected effect on energy independence include combining solar water heaters with wood-burners and wetbacks for space and water heating, and producing firewood locally with an SRC plantation. Based on the household study, transport behaviours or technologies are expected to have a larger effect on GHG emissions than papakāinga infrastructure. Recommendations include a billing/metering feasibility study potentially followed by a community PV array, an SRC trial, and solar water heaters and wood-burners with water heating for new homes

Draft Genome Sequences of Propionibacterium acnes Type Strain ATCC6919 and Antibiotic-Resistant Strain HL411PA1.

Propionibacterium acnes is a major skin commensal and is associated with acne vulgaris, the most common skin disease. Here we report the draft genome sequences of two P. acnes strains, the type strain ATCC6919 and an antibiotic-resistant strain, HL411PA1

Ultracool white dwarfs and the age of the Galactic disc

We present parallax observations and a detailed model atmosphere analysis of 54 cool and ultracool ($T_{\rm eff}$ < 4000 K) white dwarfs (WDs) in the solar neighbourhood. For the first time, a large number of cool and ultracool WDs have distance and tangential velocities measurements available. Our targets have distances ranging from 21 pc to >100 pc, and include five stars within 30 pc. Contrary to expectations, all but two of them have tangential velocities smaller than 150 km s$^{-1}$ thus suggesting Galactic disc membership. The oldest WDs in this sample have WD cooling ages of 10 Gyr, providing a firm lower limit to the age of the thick disc population. Many of our targets have uncharacteristically large radii, indicating that they are low mass WDs. It appears that we have detected the brighter population of cool and ultracool WDs near the Sun. The fainter population of ultracool CO-core WDs remain to be discovered in large numbers. The Large Synoptic Survey Telescope should find these elusive, more massive ultracool WDs in the solar neighbourhood.Comment: 16 pages, 11 figures, 4 tables, accepted for publication in MNRA

Spin recovery in the 25nm gate length InGaAs field effect transistore

We augmented an ensemble Monte-Carlo semiconductor device simulator [3] to incorporate electron spin degrees of freedom using a Bloch equation model to investigate the feasibility of spintronic devices. Results are presented for the steady state polarization and polarization decay due to scattering and spin orbit coupling for a III-V MOSFET device as a function of gate voltages, injection polarization and strain

A Dark Spot on a Massive White Dwarf

We present the serendipitous discovery of eclipse-like events around the massive white dwarf SDSS J152934.98+292801.9 (hereafter J1529+2928). We selected J1529+2928 for time-series photometry based on its spectroscopic temperature and surface gravity, which place it near the ZZ Ceti instability strip. Instead of pulsations, we detect photometric dips from this white dwarf every 38 minutes. Follow-up optical spectroscopy observations with Gemini reveal no significant radial velocity variations, ruling out stellar and brown dwarf companions. A disintegrating planet around this white dwarf cannot explain the observed light curves in different filters. Given the short period, the source of the photometric dips must be a dark spot that comes into view every 38 min due to the rotation of the white dwarf. Our optical spectroscopy does not show any evidence of Zeeman splitting of the Balmer lines, limiting the magnetic field strength to B<70 kG. Since up to 15% of white dwarfs display kG magnetic fields, such eclipse-like events should be common around white dwarfs. We discuss the potential implications of this discovery on transient surveys targeting white dwarfs, like the K2 mission and the Large Synoptic Survey Telescope.Comment: ApJ Letters, in pres

ranacapa: An R package and Shiny web app to explore environmental DNA data with exploratory statistics and interactive visualizations.

Environmental DNA (eDNA) metabarcoding is becoming a core tool in ecology and conservation biology, and is being used in a growing number of education, biodiversity monitoring, and public outreach programs in which professional research scientists engage community partners in primary research. Results from eDNA analyses can engage and educate natural resource managers, students, community scientists, and naturalists, but without significant training in bioinformatics, it can be difficult for this diverse audience to interact with eDNA results. Here we present the R package ranacapa, at the core of which is a Shiny web app that helps perform exploratory biodiversity analyses and visualizations of eDNA results. The app requires a taxonomy-by-sample matrix and a simple metadata file with descriptive information about each sample. The app enables users to explore the data with interactive figures and presents results from simple community ecology analyses. We demonstrate the value of ranacapa to two groups of community partners engaging with eDNA metabarcoding results

Construction of an instant structured illumination microscope

A challenge in biological imaging is to capture high-resolution images at fast frame rates in live cells. The “instant structured illumination microscope” (iSIM) is a system designed for this purpose. Similarly to standard structured illumination microscopy (SIM), an iSIM provides a twofold improvement over widefield microscopy, in x, y and z, but also allows much faster image acquisition, with real-time display of super-resolution images. The assembly of an iSIM is reasonably complex, involving the combination and alignment of many optical components, including three micro-optics arrays (two lenslet arrays and an array of pinholes, all with a pitch of 222 μm) and a double-sided scanning mirror. In addition, a number of electronic components must be correctly controlled. Construction of the system is therefore not trivial, but is highly desirable, particularly for live-cell imaging. We report, and provide instructions for, the construction of an iSIM, including minor modifications to a previous design in both hardware and software. The final instrument allows us to rapidly acquire fluorescence images at rates faster than 100 fps, with approximately twofold improvement in resolution in both x-y and z; sub-diffractive biological features have an apparent size (full width at half maximum) of 145 nm (lateral) and 320 nm (axial), using a 1.49 NA objective and 488 nm excitation