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Item type: Publication , Access status: Metadata only , Structural conservation of phi thickenings in diverse plant taxa(2025) Collings, David; Aleamotu'a, Maketalena; McCurdy, David• Background and Aims Phi thickenings are bands of lignified and thickened secondary cell wall that encircle root cortical cells in diverse plant taxa, including both angiosperms and gymnosperms. • Methods We used confocal fluorescence microscopy to investigate phi thickening structure from 17 plant families, and investigated how the stress hormone jasmonic acid (JA) regulates phi thickening development. • Key Results Phi thickenings from different plant families exhibit strong structural similarities, particularly between species showing Type 1 thickenings in the inner cortex, immediately outside the endodermis. JA treatments rapidly induced phi thickenings in Brassica oleracea, with secondary wall development commencing within 10 h of hormone treatments. JA also induced thickening development in all tested Brassicaceae species with the exception of Arabidopsis spp. This might be due to the loss of the inner cortex in roots from this genus. JA also triggers thickening induction in three further angiosperm families (Fabaceae, Geraniaceae, Resedaceae). • Conclusions Despite the conservation of the JA-dependent induction, we suggest that phi thickenings are not a conserved or homologous structure. Instead, phi thickenings may represent an example of convergent evolution.Item type: Publication , Access status: Metadata only , The Anatomy of Phi Thickening Development in Brassica oleracea Roots(2026) Collings, David; Aleamotu'A, Maketalena; McCurdy, DavidIn response to jasmonic acid, inner cortical cells in Brassica oleracea roots sequentially form two different secondary cell wall arrays. Initially, these cells develop phi thickenings, thick bands looped around the radial walls that are coordinated between adjacent cells to form a reinforcing scaffold. These thickenings develop later than the formation of the Casparian strip and protoxylem. Subsequently, inner cortical cells develop a reticulate network of delicate thickenings on their inner face adjacent to the endodermis. While phi thickenings initially develop in a single layer in the inner cortex, we demonstrate that multiple rings can develop in two ways, either through the occasional development of isolated thickenings in individual cells in the middle cortex, or through cell divisions in the endodermis that generate a new inner cortical layer which forms extensive phi thickenings. We also show that the phi thickening network in developing lateral roots remains separate from the network in the primary root, even as the Casparian strip re-forms a contiguous network. These anatomical observations have implications not only for understanding the developmental pathways leading to phi thickening formation but also for investigating the rare example of two different secondary wall structures being deposited in the same cell type.Item type: Publication , Access status: Metadata only , Assessing the vulnerability of the Indian renewable energy market: A quantile modeling approach(Elserier, 2027) Sinha, Avik; Wu, JingStabilizing the renewable energy market is a critical factor for India’s energy transition, and policymakers are striving to achieve this. However, the persisting policy voids in India’s energy policy scenario are restricting the renewable energy market in India from reaching its true potential. This is reflected in the reduction in renewable energy investment and generation scenario, which is subsequently affecting the renewable energy market in India. Taking the example of hydroelectricity generation, this study has made an attempt to analyze how it is impacted by geopolitical risk, oil price uncertainty, and inflation. The study has used monthly data from April 1997 to September 2024. The methods used in the study are cross-quantile correlation, quantile-on-quantile regression, and wavelet coherence. The results show that while oil price uncertainty and geopolitical risk restrict hydroelectricity generation, inflation boosts it. Suitable implications are drawn from the study outcomes.Item type: Publication , Access status: Metadata only , Re-Imagining Risk and Disruption: The Nature of Complex Unbounded Problems(Edward Elgar Publishing, 2026) Weiske, Peter; Dovers, Stephen; Durch, William; Handmer, JohnItem type: Item , Access status: Open Access , New Zealand music : into the 21st century : an investigation into the factors affecting the successful post-compositional promulgation of contemporary New Zealand music(2001-07) Hill, Carolyn.1936 was a significant year for composition in New Zealand. That year the Australian pianist and composer, Percy Grainger toured the country and, little suspecting the importance of his actions, announced a competition for an orchestral work written by a New Zealander.