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Recent Submissions
Searching for sifting through and selecting curriculum materials for mathematics planning during practicum
(MERGA, 2023) Wilson, Susanna; Reid-O' Connor B; Prierto-Rodriguez E; Holmes K; Hughes A
This paper describes results from a case study about how a primary pre-service teacher (PST) used curriculum materials (CMs) when planning for a mathematics lesson during her final practicum. The data is drawn from a doctoral study (in progress) and results show how the PST initiated an active process of searching for and sifting through CMs on a familiar website to make selections for a lesson. Selections were based on several aspects, including the mathematics focus of her lesson, curriculum connections, her chosen teaching approach and mathematical representation for teaching multiplication. Implications for mathematics Initial Teacher Educators (ITEs) are discussed.
An Overview of the Unique DC Injection Campaign for Replicating GICs on High Voltage Transformers in New Zealand
(2023) Lapthorn, Andrew; Hardie S; Subritzky S; Dalzell M; Clilverd M; Cobbett N; Beggan C; Huebert J; Eaton E; Brundell J; Rodger C
Introduction:
Between 21 and 29 January 2023, with the assistance of Transpower, we
successfully utilised New Zealand's HVDC link to directly introduce
current into the ground at Haywards substation.
Our objective was to simulate the efffects of geomagnetically induced
currents (GICs) and observe their impact on two 216 MVA, 220/110 kV
autotransformers and one 80 MVA transformer, as well as to monitor the
associated transmission lines.
Assessing paropsine damage on Eucalyptus trees with remote sensing
(Forest Growers Research, 2022) Mann L; morgenroth, justin; Xu, Cong; Pawson S
EXECUTIVE SUMMARY
New Zealand forests comprise 10.1 million hectares of forests. Due to the sheer scale of managing
these forests, remote sensing is increasingly used as a source of information for decision-making.
Information on tree growth, mortality, and health related to climate or pest activity can be monitored
and quickly mapped. Currently, no remote sensing methods exist to quantify foliar browse by
paropsine beetles on Eucalyptus. Currently, defoliation assessments are performed through visual
methods by ground-based observers. Such methods, like the Crown Damage Index (CDI), are time
consuming, particularly at larger spatial scales, and potentially suffer from observer bias.
Paropsine damage does not induce a colour change in foliage as would occur with a leaf-sucking
insect. Instead, paropsines reduce canopy density by eating parts of leaves, thus altering their shape
and area. Hence, LiDAR could be a suitable tool for paropsine defoliation assessment. This study
aimed to evaluate the potential for LiDAR as a quantitative assessment of paropsine defoliation of
Eucalyptus crowns as a replacement for the CDI.
Three LiDAR scanners (VUX-240, VUX-1LR and L1) were used to collect data from a Eucalyptus
trial in the Canterbury region (43°11'47.2"S 172°39'06.1"E) in September 2021 and March 2022. To
measure the defoliation prediction accuracy of LiDAR we simultaneously collected CDI data for 55
tree crowns at the same date as the LiDAR data. A total of 57 LiDAR metrics were extracted for each
of the 55 tree crowns. The best metrics model to predict CDI was statistically analysed with a Partial
Least Squares Regression (PLSR).
Results:
The results demonstrated 18 LiDAR metrics of interest and showed that LiDAR scanners could
predict CDI with ±19.1-23.6 % error from the actual CDI observed in the field, with VUX-240 having
the smallest error prediction (Root Mean Square Error (RMSE)=9.5 CDI units in September 2021),
followed by the L1 scanner (RMSE=10.5 CDI units in March 2022), and VUX-1LR having the highest
error prediction (RMSE=11.8 CDI units in September 2021 and RMSE=11.6 CDI units in March
2022).
Key conclusions are:
• All three scanners had comparable predictive abilities, meaning that all could possibly be
used for paropsine defoliation assessment.
• The actual error prediction shows promise as a healthy tree could be distinguished from a
heavily defoliated tree.
• More testing needs to be undertaken to increase the LiDAR defoliation prediction accuracy.
These tests should occur in sites with a broader CDI range (e.g., the Marlborough region).
• Future work needs to move away from the CDI and use a quantitative method of assessing
crown defoliation that can be compared with the remotely sensed LiDAR data. This is
important as the CDI is semi-quantitative and potentially subject to observer bias.
• More testing needs to be undertaken to determine whether LiDAR can differentiate between
paropsine beetle defoliation and trees where abiotic stresses have led to small leaves and/or
sparse crowns
The Perspectives of Māori and Pasifika Mate Kirikōpū (Endometriosis) Patients in Aotearoa New Zealand
(MDPI AG, online-publication-date) Ellis K; Tewhaiti-Smith J; Munro, Deborah; Wood, Rachael
Experiences with endometriosis have been understudied in indigenous and people of colour populations. This study aimed to investigate the experiences of Māori and Pasifika endometriosis patients in Aotearoa New Zealand. Twenty-seven Māori endometriosis participants from 21 iwi (tribes), and 10 Pasifika participants from 8 different island nations participated in online, asynchronous, anonymous text-based discussions about their endometriosis journeys. Their explanations were analysed qualitatively with an inductive thematic approach. The average delay from symptom onset to a confirmed or suspected endometriosis diagnosis was 11.6 ± 7.8 years in the Māori cohort and 12.4 ± 6.2 years in the Pasifika cohort. There were high levels of dissatisfaction with the availability of treatment, with 66.7% of Māori participants and 60.0% of Pasifika participants feeling that endometriosis treatment was not readily available to them. Poor experiences with the medical profession might dissuade Māori and Pasifika patients from seeking care, exacerbating a culture of distrust and perpetuating healthcare inequities. This could potentially be improved by increasing the capacity to take time for relationship building within general practice or through the incorporation of cultural advisors to support relationship establishment that emphasises holistic consideration of patient well-being and culturally safe care.