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Conservation in High-Field Quantum Transport
No full textThis article provides an overview of the role of microscopic conservation in charge transport at small scales and at driving field beyond the linear-response limit. As a practical example, we recall the measurement and theory of interband coupling effects in a quantum point contact drive far from equilibrium.Peer-reviewe
Random Effects Model-Based Sufficient Dimension Reduction for Independent Clustered Data
No full textSufficient dimension reduction (SDR) is a popular class of regression methods which aim to find a small number of linear combinations of covariates that capture all the information of the responses, that is, a central subspace. The majority of current methods for SDR focus on the setting of independent observations, while the few techniques that have been developed for clustered data assume the linear transformation is identical across clusters. In this article, we introduce random effects SDR, where cluster-specific random effect central subspaces are assumed to follow a distribution on the Grassmann manifold, and the random effects distribution is characterized by a covariance matrix that captures the heterogeneity between clusters in the SDR process itself. We incorporate random effect SDR within a model-based inverse regression framework. Specifically, we propose a random effects principal fitted components model, where a two-stage algorithm is used to estimate the overall fixed effect central subspace, and predict the cluster-specific random effect central subspaces. We demonstrate the consistency of the proposed estimators, while simulation studies demonstrate the superior performance of the proposed approach compared to global and cluster-specific SDR approaches. We also present extensions of the above model to handle mixed predictors, demonstrating how random effects SDR can be achieved in the case of mixed continuous and binary covariates. Applying the proposed methods to study the longitudinal association between the life expectancy of women and socioeconomic variables across 117 countries, we find log income per capita, infant mortality, and income inequality are the main drivers of a two-dimensional fixed effect central subspace, although there is considerable heterogeneity in how the country-specific central subspaces are driven by the predictors. Supplementary materials for this article are available online, including a standardized description of the materials available for reproducing the work.FKCH was supported by an Australia Research Council Discovery Project DP230101908Peer-reviewe
A generative model for exploring differences in mortality associated with stressor exposure risk in bioarchaeological contexts
No full textGenerative models are an underutilized tool in bioarchaeology that make it possible to directly interrogate how age-at-death is influenced by varied risk of exposure to stressors, while accounting for factors which are ordinarily invisible to bioarchaeologists. Further, the visibility of suspected differences within populations at the sorts of sample sizes common to bioarchaeology can also be examined, helping to inform interpretation of findings. In the present study, cohorts of 50, 100, 500, and 1000 individuals aged 0 years were generated. Each individual was assigned a frailty value, and to either high or low risk groups. These cohorts were run through simulation models in which exposure to stressors varied according to risk group and the severity of stressors if exposed. The difference in mean age-at-death between high and low risk group for each run was tested for significance using Welch's t-test. The model results are used to identify potential minimum sample sizes for bioarcheological research at which true differences in age-at-death due to difference in stressor exposure are likely to be visible. Small cohorts (50 individuals) had low likelihood of detecting true risk group differences in age-at-death except when the difference in exposure to stressors or the severity of the stressor was great enough to produce a mean difference in lifespan of >20 years. The probability of observing a true difference in age-at-death between risk groups increased when the difference in stressor exposure and/or the stressor severity increased for all cohorts. Therefore, group-level differences in lifespan may not be identifiable in small archaeological samples except where stress or inequality is high. The low reliability of results from small samples reiterates the needs to carefully examine equifinality in bioarcheological research, as demonstrated through the application of this model to a case study which examined the Late Woodland phase of the Dickson Mounds. This application assessed the three potential hypotheses put forth by Goodman and Armelagos (1988) to establish how likely they may be when sample size is not a limiting factor on visibility of potential difference within populations.BW was supported by the Australian National University Research Scholarship ( 738/2018 ) and an Australian Government Research Training Program Scholarship , LABW was supported by the Australian Research Council ( FT200100822 ).Peer-reviewe
Popular Political Attitudes in Vanuatu: Findings of the Pacific Attitudes Survey
No full textThis paper presents the findings of the second Pacific Attitudes Survey (PAS), conducted in Vanuatu from August–October 2023. Drawing on a nationally representative sample (n = 1330) of ni-Vanuatu of voting-age (18+), the PAS gauges the views of ordinary ni-Vanuatu citizens on a range of questions related to democracy, economics, governance, tradition, climate change, labour mobility and international relations. This article focuses on how ni-Vanuatu understand and participate in democracy, levels of popular trust in institutions, attitudes towards the role of government, the performance of their political system, and womenʼs participation in politics. Findings of the PAS: Vanuatu reveal high levels of popular support for democracy and trust in democratic institutions. At the same time, popular political attitudes also highlight a distinctive and widely embraced respect for kastom values and traditional leadership, and a popular preference for participating in politics through local and traditional, rather than national pathways.The Pacific Attitudes Survey: Vanuatu project was a partnership between The Australian National University, Swinburne University of Technology, the University of the South Pacific and the National University of Vanuatu. The research was jointly funded by the ANU Department of Pacific Affairs through the Pacific Research Program and the Asia Foundation. Open access publishing facilitated by Swinburne University of Technology, as part of the Wiley - Swinburne University of Technology agreement via the Council of Australian University Librarians.Peer-reviewe
Imagined Weakness: The peaceful riser identity and Beijing’s policy overcorrection in the South China Sea
No full textThis article investigates why Beijing's South China Sea (SCS) policy has become predominantly coercive under Xi Jinping. It argues that an identity-policy discrepancy, rooted in Chinese strategic culture and intensified during Hu Jintao's tenure, served as a key catalyst. The gap between Hu's peaceful riser identity and the assertive actions taken in the SCS created an 'imagined weakness' that the Xi administration sought to correct, resulting in an overcorrection that surpassed Hu's already assertive approach. By tracing shifts in China's discourse and policy over time, the article highlights the continuity between the Hu and Xi eras and examines how the former influenced the latter's strategic trajectory - a critical yet often overlooked dimension for understanding China's evolving approach to the SCS and its foreign policy more broadly.Peer-reviewe
TROPICAL ENUMERATION OF CURVES IN BLOWUPS OF CP<sup>2</sup>
No full textWe describe a method for recursively calculating Gromov–Witten invariants of all blowups of the projective plane. This recursive formula is different from the recursive formulas due to Göttsche and Pandharipande in the zero genus case, and Caporaso and Harris in the case of no blowups. We use tropical curves and a recursive computation of Gromov–Witten invariants relative a normal crossing divisor.This work was supported by ARC grant DP1093094.Peer-reviewe
Resources, Valuation, Trust: Sharing in Stem Cell Research
No full textIn biomedicine and science more broadly, there is increasing emphasis on ‘openness’ in research practices both between those involved in research and with those who might benefit from the research. Such emphasis is often invoked because it is hoped, and often assumed, that more openness will promote greater productivity, transparency and trust in scientific research. These efforts have focussed on the availability and sharing of data and knowledge, along with more tangible resources such as biological materials. Certain types of resources are valued in particular ways, and these dynamics affect the extent to which they can be entrusted and shared with others and used in more collaborative scientific research (or not). In this chapter, we use stem cell research as a case study to examine: (1) how material resources (e.g. stem cell lines) are valued in distinct (but overlapping) ways compared to more text-based resources (e.g. data, knowledge), and (2) how the valuation of these resources informs relations of trust, sharing, communication and collaboration between researchers. We draw on empirical insights from interviews with stem cell researchers in Australia, conducted as part of a research project investigating the potential for increasing ‘openness’ in Australian stem cell research. Overall, we demonstrate how scientific resources are valued in multiple ways, which informs the possibilities for more open and collaborative scientific research.Peer-reviewe
Correction to: Predesigned perovskite crystal waveguides for room-temperature exciton–polariton condensation and edge lasing (Nature Materials, (2024), 23, 11, (1515-1522), 10.1038/s41563-024-01980-3)
No full textCorrection to: Nature Materialshttps://doi.org/10.1038/s41563-024-01980-3, published online 19 August 2024. In the version of the article initially published, Daniele Sanvitto was not listed as a corresponding author. This has now been corrected in the HTML and PDF versions of the article.Peer-reviewe
Integrating Asian perspectives in Australian responsible innovation discourse: lessons from Asian bioethics
No full textPublications on responsible innovation (RI) in Australia and Asia have increased in the recent years. These outputs highlight the need to go beyond Eurocentric notions of RI and acknowledge multicultural, Indigenous, and Global South values, perspectives, and contexts. The significant number of people of Asian descent in Australia and Australia's geographical proximity to Asia necessitates a need to explore how Asian perspectives and values can be integrated into Australian RI frameworks. Building upon insights from Asian bioethics, I first underscore the need for Australian RI to account for extant notions of responsibility of its Asian populations; acknowledge common Asian values and their application to scientific research; and understand potential value differences across different Asian communities and the need to account for intersectionality. Using supportive technologies for dementia as an example, I then explore how an Asian-acknowledging Australian RI can ultimately lead to a more inclusive Australian research and innovation landscape.This work was supported by the ANU-CSIRO (Australian National University - Commonwealth Scientific and Industrial Research Organisation) Responsible Innovation collaboration. Dr. John Noel Viana is the recipient of an ARC Discovery Early Career Researcher Award (project number DE240100386) funded by the Australian Government.Peer-reviewe
Metasomatic controls on the chemical and isotopic composition of zoned clinopyroxene xenocrysts from the Mount Hope kimberlite, Gawler Craton, Australia
No full textChemical and isotopic data are presented for mantle-derived clinopyroxene xenocrysts from the Mount Hope kimberlite (191 Ma), Gawler Craton (South Australia). The data are used in conjunction with single-grain pressure-temperature (PT) estimates to study the metasomatic controls on clinopyroxene composition. Our datasets reveal a complex mantle setting that consists of three suites of clinopyroxene. Clinopyroxenes from the deep cratonic lithospheric mantle (CLM) (>150km) (herein suite C) are enriched in FeO and TiO2 with uniform rare-earth element (REE) patterns, enriched light rare-earth elements (LREEs) and unradiogenic Sr-87/Sr-86 isotopic ratios. They have chemical and isotopic compositions that overlap with clinopyroxenes from phlogopite-ilmenite-diopside (PIC) xenolith suites and low-Cr clinopyroxene megacrysts found in kimberlites elsewhere. The chemistry of the clinopyroxenes indicates an origin involving metasomatic enrichment from asthenosphere-derived melts. Clinopyroxenes from the shallow CLM (<110 km) have compositionally distinct cores (suite A) and rims (suite B). Cores have high Mg# (0.93-0.96 where Mg# = Mg/(Mg + Fe)) and Cr2O3 (0.55-2.0 wt%), and varied REE concentrations that includes HREE-depleted types. The samples have more radiogenic Sr-87/Sr-86 isotopic ratios in comparison to suite C. The clinopyroxenes equilibrated with garnet and orthopyroxene in an initially depleted peridotite source that had been enriched in LREEs prior to kimberlite magmatism. Clinopyroxene rims (suite B) are aegirine-rich and have rounded rim textures that contain inclusions of barite, apatite, perovskite, calcite, phlogopite, and richterite amphibole. They have similar Mg# and TiO2 but much lower Al2O3 and CaO contents compared to the cores. These compositions did not equilibrate with garnet or orthopyroxene. Their trace element patterns record enrichments in LREE's and high-field strength elements (HFSE), with slight depletions for Er, Tm, Yb and Lu. Both cores and rims have similar age-corrected Sr-87/Sr-86 isotopic ratios, suggesting that they are chronologically related. We suggest that the rims formed shortly before, or during kimberlite magmatism, by melt-rock interactions with the host magma. This process may have involved dissolution and reprecipitation of portions of the suite A cores. Taken together, our results provide new insights into the metasomatic compositions of clinopyroxenes from the Gawler Craton and the important roles that low-volume melts from the asthenosphere play in the chemical and isotopic enrichment of the cratonic lithosphere, and transportation of volatiles and incompatible elements.ZS acknowledges financial and research support from the Exploring for the Future program of Geoscience Australia. Chemical analyses were obtained at the Centre for Advanced Microscopy, a division of Microscopy Australia, an organization that is funded by the Australian National University and the state and federal government of Australia. The instrumentation at Macquarie University was funded by ARC LIEF, DEST Systemic Infrastructure Grants and enabled by NCRIS via AuScope. Brett Knowles, Monika Misztela, and Bei Chen are kindly thanked for their assistance with LA-ICP-MS analyses. Steven Cooper (Orogenic Exploration) is kindly thanked for providing samples and his involvement in the project. Greg Shellnutt is thanked for editorial handling. Sebastian Tappe and two anonymous reviewers are kindly thanked for their detailed comments on the manuscript.Peer-reviewe