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CLTC-PL: A Robust Mathematical Framework and Algorithm for InSAR Phase-Linking Using the Central Limit Theorem of Circular Statistics
No full textPhase-linking (PL) plays a crucial role in distributed scatterer (DS) synthetic aperture radar interferometry (InSAR), but conventional approaches often rely on strong prior assumptions about the underlying data distribution and involve solving highly nonlinear optimization problems. In this study, we propose a novel PL framework based on the central limit theorem for circular statistics (CLTC) data, which models interferometric phases through trigonometric moments and avoids any prior assumptions about the data distribution. The CLTC-PL formulation transforms the originally nonlinear PL problem into inherently well-posed and locally linear weighted least-squares estimation, enabling efficient optimization with minimal iterations and error propagation analysis. The proposed method offers clear structural transparency and statistical interpretability, while having strong estimation performance. This work not only improves robust phase estimation but also introduces a model-free framework where a multivariate normal distribution of trigonometric moments arises naturally via CLTC, allowing statistically grounded inference. Both simulated and real-data experiments validate the effectiveness of the proposed PL mathematical framework
Redox proteomics combined with lipidomics and metabolomics to elucidate the mechanism of ferroptosis in colorectal cancer using human colorectal carcinoma HCT-116 cells
No full textAbstract Background: Colorectal cancer (CRC) ranks as the third leading cause of cancer-related death worldwide, and the second leading cause of cancer-related deaths in New Zealand. It is frequently driven by mutations in key oncogenes and tumor suppressor genes. Current treatment modalities for CRC, offer only limited efficacy, as many chemotherapeutic agents fail to elicit consistent responses across patient populations. This clinical challenge underscores the urgent need for novel therapeutic strategies. Ferroptosis, first described in 2012, is an iron-dependent form of regulated cell death characterized by the accumulation of lipid peroxides and reactive oxygen species (ROS). Increasing evidence has demonstrated that ferroptosis selectively targets vulnerabilities in cancer cells, particularly in iron metabolism and oxidative stress pathways, making it a promising therapeutic avenue for CRC. Furthermore, modulation of ferroptosis pathways has been shown to enhance the anti-tumor efficacy of conventional chemotherapeutics. A better understanding of the initiation, propagation, and resistance mechanisms of ferroptosis in CRC is therefore critical for the development of ferroptosis-based therapeutic interventions. During ferroptosis, cysteine thiol groups serve as direct targets of ROS and act as reversible “redox switches” through oxidative modifications such as disulfide bond formation or thiol oxidation. These modifications regulate key physiological processes, including metabolic reprogramming, oxidative stress responses, and cell survival. The goal of the research is to identify novel redox-regulated proteins, lipid species, and metabolites associated with ferroptosis, generate new insights into the molecular mechanisms of ferroptosis in CRC, and ultimately contribute to the identification of potential biomarkers and therapeutic targets for CRC treatment. Methods: In this study, the human colorectal carcinoma cell line HCT-116 was used as the experimental model. Ferroptosis was induced by treatment with ferric ammonium citrate (FAC), and phenotypic changes were characterized through a combination of morphological observation under a microscope, cell counting using hemocytometer, CCK-8 metabolic activity assay, and ROS assay.To investigate the oxidative modification of cysteine thiol groups of proteins extracted from the studied cells, we employed a quantitative proteomics approach. We employed an isobaric labeling strategy using the iodoTMT6plex reagent to selectively label reversibly oxidized thiols on cysteine residues. An anti-TMT resin-based enrichment step was then applied to enrich iodoTMT-labeled peptides and reduce interference from non-target peptides during liquid chromatography tanden mass spectrometry (LC-MS/MS) analysis. Protein and peptide identification and quantification were performed using LC-MS/MS and Proteome Discoverer software, enabling comprehensive analysis of redox modifications at the peptide and protein levels.Differential expression analysis was conducted using the MSstatsTMT package to identify proteins exhibiting significant redox changes. These proteins were further subjected to pathway and network analysis using STRING (for protein–protein interaction (PPI) and Gene Ontology (GO) enrichment) and WebGestalt (for KEGG and GSEA pathway enrichment).Lipidomic and metabolomic analyses were also performed to explore ferroptosis-related metabolic alterations. LipidSearch was used for lipid identification and quantification, followed by statistical analysis in MetaboAnalyst. For metabolites, Compound Discoverer was used for identification and differential analysis of metabolites, with manual curation to improve accuracy. Pathway enrichment was then performed using WebGestalt. Results: Redox proteomics identified 45 redox-modified proteins associated with 79 oxidized cysteine sites, of which 5 oxidation sites were newly discovered in this study. Furthermore, two newly discovered redox-regulated proteins, PPP1R9B and S100A16, were identified. Among these 45 proteins, MDH2 and PRDX3, have been both previously reported to be associated with ferroptosis. Pathway enrichment analysis revealed a high involvement of endoplasmic reticulum (ER)-related processes, such as protein folding and ER lumen organization. PPI network analysis further identified 15 highly interconnected hub proteins, including CALR, HSPA9, PDIA3, HSP90B1, and HSPD1. Most of these ER-associated may serve as key mediators of redox regulation during ferroptosis. Lipidomic profiling identified 67 significantly altered lipid species, among which CerP(d15:0/2:0), PE(16:0e/8:0), PIP3(37:3/13:1), PE(8:0p/10:0), PIP2(16:1/21:6), PIP2(37:0/19:0), and PIP3(37:1/13:1) showed potential as ferroptosis-related biomarkers. Metabolomic analysis identified 27 dysregulated metabolites, including L-arginine, spermine, spermidine, and N1-acetylspermidine, which were significantly changed under ion-induced oxidative stress.Integrated pathway analysis of lipidomic and metabolomic datasets showed strong convergence on L-arginine and polyamine metabolism pathways. Additionally, HIF-1 signaling was implicated as a potential regulatory axis in ferroptosis within CRC cells. In summary, this study provides a comprehensive multi-omics landscape of iron-induced ferroptosis in HCT-116 cells, integrating redox proteomic, lipidomic, and metabolomic underlying ferroptosis initiation and execution, and to uncover novel ferroptosis-related molecular candidates such as CALR, CerP(d15:0/2:0), and ether phospholipids.</p
From Source to City: Using Ambient Noise to Characterise Shaking from the Alpine Fault, New Zealand.
No full textThe Alpine Fault is a major seismic hazard in New Zealand. Yet, there is no empirical data on ground shaking caused by a major Alpine Fault earthquake, as no such event has been recorded instrumentally. Regardless, paleoseismic studies provide an earthquake cycle of ∼300 years, with the last rupture occurring in 1717 AD. This research exploits the ambient seismic field to improve our understanding of ground motion after an Alpine Fault earthquake. The study has three key objectives: characterising the ambient seismic noise field in the South Island, calculating robust Green's functions using ambient noise records, and computing Virtual Earthquakes to simulate future Alpine Fault ruptures. The spatiotemporal characteristics of the ambient noise field are analysed through a Maximum Amplitude Rotation (MAR) analysis and the asymmetry of the coherency-based noise functions, revealing insights into the energy sources and seasonal variations of the secondary microseismic peak. The second microseismic peak has strong sources in the south and east of the South Island. The study evaluates cross-correlation, deconvolution, and coherency methods for extracting Green’s functions from the ambient noise field, concluding that coherency is the most reliable due to its amplitude preservation. These functions are then used in the Virtual Earthquake Approach to generate virtual waveforms simulating buried double-couple sources. Corrections for source depth, radiation pattern, and source duration are applied, and the virtual earthquakes are validated against real seismic records. The methodology is further extended to simulate finite rupture scenarios, integrating a homogeneous slip model with virtual waveforms to estimate long-period ground motion for potential Alpine Fault earthquakes. To achieve all this, we installed the SALSA network, a temporary network of 47 seismic stations along the Alpine Fault trace.</p
Whenua-First Living Landscape-Led Development
No full textThis practice-led research critically explores the intersection of regenerative design and environmental justice in greenfield housing within the context of sprawling urban residential growth, and disjunction from the kinship of the landscape. Against these prevailing extractive modes of development the project investigates conditions for the inclusion of housing and human community alongside and with other lifeforms present within Tawera/ Springfield in the Selwyn District of Canterbury. By attending to the complex inter-relationality of species, materials, geologic histories and narratives that constitute the landscape, a hyper-localised design response, or design kaitiaki, is critically generated. Through design, justice and the right to thrive is taken up as a multi-species, spatial and eco-centric concern. At the root of this ambition is the question of whom does design serve? The research is undertaken across three primary phases: Hyper-local site study, Landscape systems’ response, and Sympoetic design. This research prompts a pre-emptive shift in how the lands of Aotearoa might be spatialised by non-extractive housing development with ecological sensitivity. The research finds ways to demonstrate pathways for regenerative design amongst ever-dwindling resources amid growing population.</p
Magmatic volatile emissions from arc volcanoes in the southwest Pacific Ring of Fire
No full textVolcanism at subduction zones plays a pivotal role in the geochemical cycling of elements between the Earth’s mantle, crust, and surface. Active volcanoes emit high concentrations of gases and aerosols, which influence the habitability of planet Earth by acting both as absorbers and reflectors of sunlight, as natural fertilizers and hazardous pollutants in the hydro- and biosphere. This thesis compares the current geochemical signatures of magmatic volatiles emitted by three different volcanic systems situated in three different volcanic arcs of the southwest Pacific Ring of Fire using a multi-instrumental sampling and measurement approach that combines ground- and drone-based in-situ sample collection as well as remote sensing measurements (e.g., filter packs, cascade impactors, alkaline traps, multi-GAS and DOAS instruments), as well as petrological techniques. In order to successfully collect near-plume samples by drone, a new deployment configuration for filter-based instruments has been designed, built and successfully used in this work.The first case study at the open-vent degassing volcano of Mt. Yasur (Republic of Vanuatu) reveals a significant increase in average magmatic gas flux between 2022 (1894 ± 649 t/d SO2) and 2023 (3183 ± 919 t/d SO2). This was not detected by satellite remote sensing but is consistent with an increasing state of unrest following the occurrence of in-crater landslides. For the first time, measured plume characteristics reveal signs of high-temperature magmatic gas scavenging within the crater area by the development of ash coatings while measurements at altitude along the plume trajectory outside of the crater highlight an increase and survival of magmatic gas concentrations, especially bromine, up to one kilometre from the vents. Corresponding plume aerosol concentrations fall by an order of magnitude in concentration within one kilometre from their source vents, but elements of magmatic volatile behaviour are still dominant in fine aerosol modes at distance, highlighting how locally complex plume conditions include slow aerosol growth and mixing of the plume with ambient air, as well as phases of strong passive degassing and secondary aerosol formation in-between Strombolian eruptions.The second case study at the hyper-acidic Te Wai ā-moe crater lake on the summit plateau of Mt. Ruapehu (New Zealand), in contrast to Mt. Yasur, represents a hydrothermally dominated magmatic system. Here, geochemical measurements of the volcanic plume compositions demonstrate and characterize a period of open-vent-like degassing through the crater lake. Although no visual signs of degassing were observed, two distinct phases of changing magmatic plume compositions including hydrogen halide and secondary metal aerosol emissions are revealed during this prolonged cooling phase of the lake. The multi-instrumental approach thus proved crucial in detecting an otherwise unnoticed phase of magmatic degassing highlighting volatile exsolution of CO2, SO2, and metal compounds in the shallow subsurface during an exceptionally long lake heating cycle (> 9 months). The degassing compositions mirror that of the 2006-07 heating cycle, which corresponds to the time period of the last explosive eruptions, but were accompanied by much higher emission rates, providing critical insight to future eruptive forecasting.The third case study investigates the role of volatile-rich magma recharge at Ulawun volcano (Papua New Guinea) using petrological techniques to explain the recent ( 50%), whole rock geochemistry showed a shift from a previous basaltic-andesitic to a now purely basaltic magma composition, while plagioclase geothermometry revealed high potential melt water contents (> 4 wt.%) and overall mineral-melt disequilibria prior to the eruptions. It is thus inferred that one or more mafic recharge events caused the onset of the 2019 eruptive sequence at Ulawun by causing increased buoyant magma ascent and rapid undercooling of the melt, leading to the explosive release of volatiles within an ultimately very viscous melt.This thesis therefore provides insights into magmatic volatile emissions, volcanic plume dynamics, and mafic recharge of magmas from three different volcanic arcs of the southwest Pacific Ring of Fire, highlighting the novel utility of modern technology for collecting unique magmatic signatures even from hydrothermally dominated magmatic systems and remote volcanoes. It involves a data-supported discussion of future geochemical plume monitoring during phases of elevated volcanic unrest and shows new insights on the influence of magmatic aerosols on volcanic plume chemistry as well as the contribution of magmatic processes to strongly explosive basaltic eruptions (VEI ≥ 4).</p
Māori and Minerals: Revisiting Taonga and the Treaty
No full textThe return to government in November 2023 of a National Party coalition saw the return of support for the mining sector in New Zealand following two terms of a Labour Party coalition that banned new offshore petroleum exploration, and promised there would be no new mines on conservation land. Since their return to government, the National Party coalition has introduced the Crown Minerals Amendment Bill 2024 which will, amongst other things pro-mining, reverse the ban on offshore petroleum exploration. In addition, the Coalition has legislated the Fast-track Approvals Act 2024 aimed at making it easier and quicker to gain approvals for development including mining, and have committed $200 million for co-investment in petroleum exploration. What was a natural resource of declining interest to Māori given the Labour Party’s transitioning of New Zealand towards a zero-carbon economy, might still be something of relevance today and into the future. The Waitangi Tribunal found in favour of a Māori ownership interest in petroleum in The Petroleum Report 2003, a logical and persuasive report which was rejected by the Crown. The Waitangi Tribunal was ambivalent in its conclusions on a Māori ownership interest in gold in The Hauraki Report 2006 and Te Tau Ihu Report 2008. This thesis revisits that debate. It reconsiders the guarantee of active protection under Article two of the Treaty in relation to the Crown Mineral Estate. It contends the Tribunal did not fully consider the arguments submitted, nor consider other potential arguments. Had it done so, different conclusions might well have eventuated and the Crown’s response might also have been different.</p
New Zealand English and Te Reo Māori: A critical perspective on the loanword narrative using data from translingual picturebooks
No full textAims/Purpose: New Zealand English has been characterised by the use of vocabulary ‘borrowed’ from the Indigenous Māori language since early contact between English and Māori speakers. In this paper, we consider the relevance of the ‘loanword narrative’ to New Zealand English, examining data from translingual picturebooks published in Aotearoa New Zealand. Design/Data: We built a small corpus of 10 translingual picturebooks spanning a 30-year period beginning in the early years of Māori language revitalisation. Analysis: We applied techniques of language analysis from descriptive linguistics, including studies of loanwords. Findings: We find some evidence of linguistic ‘borrowing’. Originality: However, in texts created by Māori content creators, with Māori cultural themes, a language practice akin to pedagogical code-switching or pedagogical translanguaging is observed. Māori content creators alternate between languages, treating Māori lexemes as distinct from NZE, preserving Māori orthographic traditions, and providing translation, explanation, or contextual support of Māori lexemes for NZE reader comprehension. Our observations find parallels in translanguaging studies in bilingual early childhood settings, and they are supported by new psycholinguistic research that has identified the development of substantial body of linguistic knowledge about the Māori language by non-Māori speakers through societal exposure. Significance: We argue that the prevailing loanword narrative does not account for Māori language usage in translingual picturebooks developed by Māori content creators. Rather, we find a clear pattern of differentiation between Māori and NZE
#WeToo: The Experiences of Sex Workers who are Survivors of Sexual Violence in their Personal Lives
No full textEmploying a qualitative methodology and a sex worker’s rights lens, this thesis provides a valuable contribution to two bodies of literature on sex work and sexual violence. An abundance of existing literature infers that sexual violence is a precursor to sex work. However, very little research draws on the lived experiences of sex workers who are survivors of sexual violence. As such, this thesis contributes to knowledge by offering insight into the lived experiences of sex workers who are survivors of sexual violence in their personal lives. Specifically, this research examines how survivors experience sex work, the extent to which they feel able to disclose experiences of sexual harm alongside their sex work, and how they feel about the support available for survivors of sexual violence who are working in the sex industry. Drawing on data from in-depth interviews with eight sex workers and five key informants, this thesis highlights the nuances and complexities of participants experiences, and challenges simplistic generalisations about sex workers who are survivors of sexual violence. Participants reported a range of motivations for beginning sex work. A majority of participants rejected the narrative that sexual violence leads to sex work, and did not feel that their sex work negatively impacted them as a survivor. While participants were not ashamed of their sex work, several were reluctant to access support for their experiences of sexual harm, fearing the consequences of disclosure. However, those that had accessed support reported diverse experiences of accessing support, with some participants sharing positive experiences. Lastly, participants made recommendations to ensure adequate care for survivors of sexual violence working in the sex industry. The conclusion of this thesis is that the experiences of survivors engaged in sex work are diverse. Respecting these diverse realities is essential to resist stigma, support capacity for healing, and to foster support trauma informed, rights-based practice among professionals supporting survivors who are working in the sex industry.</p
A marae-based tikanga framework for the future
No full textIn response to the global climate crisis, Te Herenga Waka—Victoria University of Wellington embarked on an ambitious Living Pā building project to construct a 3,000-square-metre three-storey learning, teaching, research and engagement space as part of Te Herenga Waka Marae on its Kelburn Campus. While preparing to move into the new building, a research team investigated how the International Living Future Institute’s Living Building Challenge™ sustainability principles that underpin the Living Pā project could complement the tikanga Māori that regulate the marae community. This article shares a tikanga framework developed to bring the philosophies of te ao Māori and living buildings together, explaining the key components of the framework and providing case study examples of how it applies in practice. Ultimately, this research sought to support a marae community into more climate-adaptive and resilient practices that could mitigate climate change without compromising on tikanga to achieve he pā anamata, a marae for the future
Indigenising Development and Mental Health Spaces in Solomon Islands
No full textIndigenous Solomon Islanders’ conceptualisations of space, place, and identity are central to their engagement with mental health, underscoring the need for development aid-funded counselling initiatives to integrate local knowledge systems, worldviews, and socio-cultural structures. This thesis examines how such initiatives in Honiara can be made more culturally meaningful by embedding Indigenous spatial practices and perspectives into mental health care.A qualitative case study approach was employed, focusing on the Social and Emotional Well-being (“TokSpot”) Project (2020–2025), a youth mental health initiative in Honiara funded through ChildFund New Zealand’s Solomon Islands IMPACT Programme and implemented by the Honiara City Council. The project is informed by Te Whare Tapa Whā (Durie, 1994), a holistic Māori health framework, raising critical questions about its applicability within the Solomon Islands context.The research explores two key questions: (1) How do Indigenous Solomon Islanders’ conceptualisations of space, place, and identity influence perceptions of and engagement with conventional counselling in Honiara? (2) How can the Māori Te Whare Tapa Whā framework contribute to the development of culturally relevant mental health care in Honiara? Data collection was conducted through tok stori, a Melanesian oral tradition, with 15 participants of Indigenous Solomon Islands origins.Findings indicate that counselling is understood through three primary dimensions: counselling as place(s) and space(s) for talk, counselling as shared space(s), and counselling as a practice of cultural continuity. The adaptation of Te Whare Tapa Whā reveals both opportunities and challenges, including tensions between Western paradigms, the exclusion of Christian values, and limitations on Indigenous agency in project design. The study recommends integrating traditional communal practices and Indigenous governance structures to enhance cultural relevance in mental health interventions.This research contributes to the discourse on culturally grounded mental health interventions within Indigenous geographies, offering insights for policy and practice in development aid initiatives in Solomon Islands.</p
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