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Advanced theoretical modeling methodologies for electrocatalyst design in sustainable energy conversion
No full textElectrochemical reactions are pivotal for energy conversion and storage to achieve a carbon-neutral and sustainable society, and optimal electrocatalysts are essential for their industrial applications. Theoretical modeling methodologies, such as density functional theory (DFT) and molecular dynamics (MD), efficiently assess electrochemical reaction mechanisms and electrocatalyst performance at atomic and molecular levels. However, its intrinsic algorithm limitations and high computational costs for large-scale systems generate gaps between experimental observations and calculation simulation, restricting the accuracy and efficiency of electrocatalyst design. Combining machine learning (ML) is a promising strategy to accelerate the development of electrocatalysts. The ML-DFT frameworks establish accurate property-structure-performance relations to predict and verify novel electrocatalysts' properties and performance, providing a deep understanding of reaction mechanisms. The ML-based methods also accelerate the solution of MD and DFT. Moreover, integrating ML and experiment characterization techniques represents a cutting-edge approach to providing insights into the structural, electronic, and chemical changes under working conditions. This review will summarize the DFT development and the current ML application status for electrocatalyst design in various electrochemical energy conversions. The underlying physical fundaments, application advancements, and challenges will be summarized. Finally, future research directions and prospects will be proposed to guide novel electrocatalyst design for the sustainable energy revolution.</p
Digging in Deep: Size and Site-Specific Variation in Burrow Morphology and Behaviour of the Mud Shrimp, <i>Trypaea australiensis</i> Dana, 1852
No full textThe importance of habitats, particularly burrows, for intertidal crustaceans is multifaceted. These habitats provide crucial shelter, food sources, and reproductive advantages that are essential for enhancing survival and fitness. However, maintaining these habitats can be costly, influencing whether individuals adapt to or relocate under changing environments. Burrowing mud shrimp present challenges when it comes to studying their behaviours and burrow morphology, owing to their cryptic lifestyle. In this study, we investigated burrow morphology and burrowing behaviour in the mud shrimp, Trypaea australiensis, to better understand the importance of burrows for these organisms. Firstly, we quantified burrow morphology in situ using resin casts and 3D imagery at two locations. Secondly, we examined shrimp burrowing behaviour in custom-made aquarium cuvettes in the laboratory. Resin casts showed that burrows at Shoalhaven Heads exhibited larger burrows with greater variation in the length of burrow measurements compared to burrows at Port Hacking. Laboratory observations of burrowing behaviour demonstrated that shrimp dedicate a large proportion of time to maintaining the structure of their burrows, irrespective of time of day or shrimp sex. Differences were observed between size categories, where smaller individuals were observed sitting significantly more and ventilating significantly less compared to larger individuals. Overall, our study provides a quantitative insight into the importance of burrow habitats and provides the first insights into burrowing behaviour and burrow structure for this endemic ecosystem engineer.</p
Detection and mapping of Antarctic lichen using drones, multispectral cameras, and supervised deep learning
No full textThe difficulty of accurately detecting lichens in Antarctic landscapes, due to their fine-scale spatial patterns and low spectral contrast, drives the need for high-resolution drone-based remote sensing imagery to develop and validate robust mapping methods. Few studies have explored the use of remote sensing and deep learning (DL) techniques for mapping and monitoring lichen density in Antarctic regions. This study aims to fill this gap by using multispectral (MS) cameras onboard uncrewed aerial vehicles (UAVs) and DL to detect and map Antarctic lichen through a workflow that enhances detection using a semi-automatic labelling technique based on vegetation indices (VIs). This methodology was validated through a data collection campaign at Robinson Ridge, Windmill Islands, Antarctica in January 2023. Two DL methods were evaluated to classify and map Usnea spp., Umbilicaria and Pseudephebe species (black lichen), moss and non-vegetation: method (1) standalone DL model fitting, namely fully convolutional network (FCN), U-Net, and Deeplabv3+, with semi-automatic labelling thresholding using VIs; and method (2) ensemble stacking by using eXtreme gradient boosting (XGBoost) as the input model, whose predictions are used as features for training a U-Net model. In Method 1, U-Net exhibited the best performance over the other models. Specifically, for Usnea spp., the results demonstrate an intersection over union (IoU) of 84%. Also, the black lichen class obtained an IoU of 86%. In contrast, Method 2, which employed the ensemble stacking technique, demonstrates an IoU of 71% for Usnea spp. and IoU of 75% for black lichen. This study provides promising evidence that using MS cameras on UAVs combined with DL models is an effective approach for detecting and mapping lichen density in Antarctica, though further exploration across diverse regions is recommended to validate its scalability and adaptability.</p
Exploring rural Nurses' preparedness and post-resuscitation experiences. An ethnographic study
No full textAim: The focus of this paper is to provide a detailed ethnographic exploration of rural nurses' experiences of their resuscitation preparedness and the subsequent post-resuscitation period. Design: An ethnographic study across two small rural hospital sites in New South Wales, Australia. Methods: Fieldwork was undertaken between December 2020 and March 2022 and included over 240 h of nonparticipant observation, journalling and interviews. Data were analysed using reflexive thematic analysis. Results: The first key theme—‘Sense of Preparedness’—included three subthemes: ‘Gaining experience’, ‘Issues with training and education’ and ‘Lack of warning’. The second key theme ‘Aftermath’ comprised two subthemes: ‘Getting on with it’ and ‘Making sense of the resus’. Conclusion: This study has highlighted the intricate relationship between resuscitative preparedness and the post-resuscitation period in shaping rural nurse's experiences and their well-being. Rural nurses are asking for an authentic and contextually relevant training experience that mirrors the unique rural challenges they experience. In the absence of frequent resuscitation presentations, the post-resuscitation period should be viewed as a crucible moment that can be leveraged as a valuable learning opportunity enhancing rural nurses' sense of preparedness and the provision of quality resuscitation care. Impact: Having a greater level of insight into the challenges that rural nurses experience in the pre- and post-resuscitation period is critical. This insight opens the door for fortifying policies and work processes that will better support rural nurses in the resuscitation environment. Reporting Method: Reporting complied with COREQ criteria for qualitative research. No Patient or Public Contribution: This study explored the experiences of rural nurses. No patient data were collected.</p
Evaluating five shoreline change models against 40 years of field survey data at an embayed sandy beach
No full textRobust and reliable models are needed to understand how coastlines will evolve over the coming decades, driven by both natural variability and climate change. This study evaluated how accurately five popular ‘reduced-complexity’ models replicate multi-decadal shoreline change at Narrabeen-Collaroy Beach, a sandy embayment in Sydney, Australia. Measured shoreline positions derived from approximately monthly field surveys were used for 20-year calibration and 20-year validation periods. The models performed similarly on average but with large variability between transects. The set-up of several models was modified to compensate for their sensitivity to imperfect input wave data, and further site-specific improvements were identified. Capturing interannual to decadal-scale variability in cross-shore and longshore dynamics at this site was challenging for all five models. Models appeared to aggregate key processes at this timescale into parameter values rather than representing them directly. This suggests time-varying parameters or changes to model structure may be necessary for decadal-scale simulations.</p
The Role of Within-Person Variability Information in Unfamiliar Face Identification
No full textUnfamiliar face identification is known to be highly error prone, yet it is relied upon in various high-stakes practical contexts including border security and the criminal justice system. Conversely, people are highly adept at identifying familiar faces and thus familiarity transforms our ability to identify faces. One factor that makes familiar face identification easier is the encoding of how the face can vary in appearance, or within-person variability information. An understanding of within-person variability could form a crucial part of face learning. Based on this logic, researchers hypothesized that unfamiliar face identification could be improved by providing within-person variability information in a recognition task. Since this idea was first proposed, many studies have found evidence that this method improves unfamiliar face identification. The presentation of within-person variability information in the form of image arrays containing multiple naturalistic images of an identity has been shown to improve people’s ability to match unfamiliar faces relative to single images. However, some studies have failed to replicate this multiple image advantage, and recent research has produced directly conflicting results regarding the circumstances under which such an advantage is observed. This has led to the suggestion that the multiple image advantage may be dependent upon the way information from an array is encoded for identification and thus will only be observed in tasks that include a memory component or require observers to abstract an identity representation from the array. This thesis explored the role of within-person variability information from multiple image arrays in unfamiliar face identification, with a novel focus on clarifying the circumstances under which a multiple image advantage will occur in unfamiliar face matching tasks and understanding how people are encoding information from multiple image arrays. Studies 1 and 2 tested various experimental conditions and their effect on the multiple image advantage. Study 1 manipulated level of variability in the images, the presentation style of images, and decision types, while Study 2 manipulated the positioning of images on the screen. Together, these studies found that task conditions do influence the presence and magnitude of a multiple image advantage. In particular, task conditions that encourage observers to abstract information from an array are conducive to a multiple image advantage. To investigate the role of an abstracted identity representation in the multiple image advantage, Study 3 tested how people encode information from a multiple image array. The results of this experiment found that participants were best at matching targets to arrays when the targets were averages of all the array images or images from the array. This suggests that when observers are presented with a multiple image array in a sequential matching task, they create an averaged representation and also retain information about individual images (exemplars). Finally, Study 4 tested whether how information from multiple image arrays is encoded can be manipulated by task instructions. Results showed that task instructions which directed participants to create an averaged identity representation from an array were not effective in producing a multiple image advantage. The findings of this thesis support the idea that abstraction of an identity representation for use in unfamiliar face identification is what drives the advantage for multiple image arrays over single images. Consequently, experimental conditions that encourage abstraction of identity information from an array are more likely to produce a multiple image advantage. This thesis demonstrated for the first time that this identity representation integrates information about variant and invariant features of a face and can be robust enough to facilitate both recognition and discrimination of unfamiliar faces. In this way, multiple image arrays can facilitate early face learning for the improvement of unfamiliar face identification.</p
Investigating the self-determination of autistic university students: A grounded theory study
No full textThe relationship between self-determination and success at university is well documented with university students identifying the use of self-determination skills as critical to their success. Autistic students in university currently experience high rates of withdrawal and report ongoing challenges with navigating the university environment and using skills commonly associated with self-determination. However, to date, there has been limited investigation of the self-determination of autistic students in university or the factors that influence their use of self-determination skills. The current study was conducted to address this gap by examining the perceptions of students and others about their self-determination at university and the personal-environmental factors that influence their self-determination and use of self-determination skills.A grounded theory design was used to examine the experiences of 14 autistic university students undertaking various academic disciplines and levels of study. Experiences were explored through the perspectives of university students as well as university staff and significant others who were supporting the students during this time. In the first phase of the study, interviews were used to explore the perspectives of the students, university staff and significant others about students’ self-determination, use of self-determination skills and experiences and factors that were felt to influence these. Students also completed a measure of self-determination. In the second phase, five of the student participants engaged in a collaborative planning process in which they worked with a facilitator to develop, implement and reflect on a plan to address a goal they were currently experiencing at university. This provided a means of dynamic assessment through which to observe changes in students’ self-determined actions in real time provided an insight into students’ perceptions as they utilised skills in real time.Findings revealed that students possessed a range of self-determination skills, but often did not utilise skills in the university context. Students’ self-determination fluctuated, depending on their interactions within the university environment and the intersection of a range of environmental and student factors. Underpinning these factors was the perspectives of students and staff and the degree to which these perspectives were shared or disconnected. Environmental factors influencing sense of self-determination and use of self-determination skills included mutuality of perspectives, and both effective and meaningful communication. When perspectives were shared, students and staff exchanged more meaningful information and communication which resulted in greater self-determination of students, while differing perspectives between students and others left students’ needs unfulfilled and decreased their sense of self-determination and belief in their ability to affect outcomes. Student related factors influencing self-determination included sense of self, students’ past and current experiences, and levels of passion and resilience.These findings contribute to knowledge of self-determination of autistic individuals as well as relevance of self-determination and casual agency theories for autistic individuals. In creating a theory of autistic self-determination in university contexts, this study provides a foundation for researchers seeking to develop effective practice to support self-determination of autistic students in university contexts. Findings suggest that understanding the interactions between the individual and environment is essential to developing self-determination of autistic individuals. The theory developed in this study illustrated that possessing self-determination skills alone was not enough to enable students to engage in self-determined actions in the university environment.</p
Characterising Non-Intentional Supraharmonic Emissions from Inverters in Power Grids: Review and Challenges
No full textSupraharmonic emissions, referred to as voltage/current waveform distortions in the 2–150 kHz range, have been identified as an emerging power quality concern. With the increased number of non-linear devices connected to the power grid, such as photovoltaic inverter systems, supraharmonic disturbances are expected to increase. Despite being a source of supraharmonic emissions, power electronic equipment has become a ubiquitous technology due to recent advancements. Similarly, researchers around the world have started studying these emissions; however, complete systematic knowledge concerning supraharmonic emissions is yet to be achieved. This paper uniquely delves into characterising emissions using existing knowledge, significantly improving the understanding of their complex micro-level interactions and highlighting emerging challenges. The paper presents a comprehensive summary integrating existing studies on supraharmonic emissions in five key areas: emissions, propagation and attenuation, measurement techniques, modelling and simulation, and mitigation.</p
Developing nursing students’ knowledge in breastfeeding [DESTINI] Project
No full textBackground: Globally, healthcare providers, including Registered Nurses, often lack the expertise needed to fully support breastfeeding women, contributing to unmet World Health Organization breastfeeding recommendations. Many new nurses frequently feel unprepared to assist in neonatal and paediatric settings. Furthermore, the growing diversity among nursing students requires innovative approaches to meet varied learning needs. Legitimation Code Theory (LCT) offers a promising framework to address these challenges in nursing education.Aim: The aim of the Developing nursing students’ knowledge in breastfeeding [DESTINI] Project was to explore how LCT could inform the design and development of an online breastfeeding education module. Specifically, the project focused on how nursing students developed knowledge and investigated their learning experiences of the LCT informed learning materials.Methods: A case study methodology approach was used to achieve the research aims. The thesis was organised as a series of four published papers. Paper 1 explored nursing students’ knowledge of breastfeeding and the sources of that knowledge. Paper 2 reviewed the application of LCT in the biological and health sciences and assessed its suitability as a framework for nursing education. Findings from Paper 2 also informed the design of the breastfeeding module and the analysis of the research project data. Paper 3 described the LCT-based design of the breastfeeding module and presented a thematic analysis of students’ experiences, based on semi-structured interviews. Paper 4 reported on students' knowledge development during the breastfeeding module, analysing both coursework artefacts and interview data.Findings: The project revealed that while nursing students had a solid understanding of lactation physiology, they struggled with practical breastfeeding support. Nursing students’ knowledge sources included both personal experiences and formal education. The LCT informed breastfeeding module was well-received, with students appreciating its unique structure. The Specialization dimension of LCT provided insight into how students fluidly integrated personal experiences with theoretical knowledge illustrating a non-linear path towards becoming the 'right kind of knower' in nursing practice.Discussion: The project demonstrated the effectiveness of LCT as a framework for course development and analysis in nursing education. It highlighted the significance of bringing students’ informal knowledge into conscious awareness, allowing them to critically examine and consider these insights. This process created opportunities to align informal knowledge with formal learning experiences, particularly in skills like breastfeeding support. Integrating personal experiences into nursing education proved valuable for building both knowledge and professional identity. The dynamic, non-linear nature of knowledge acquisition and knower development revealed by the Specialization dimension of LCT, offer new insights into the learning process for nursing education.Conclusion: The DESTINI project demonstrated that applying LCT in nursing education can effectively support the development of both disciplinary knowledge and professional identity. The module structure, based on the concept of the semantic wave, enabled students to bridge the gap between abstract theoretical concepts and practical applications. The Specialization dimension illustrated that knowledge development in nursing is not a straightforward progression, instead students moved dynamically between different forms of knowing, meaningfully integrating personal experiences with theoretical knowledge. These insights have implications for nursing education design and delivery.</p
Groups and Their Actions in Unbounded Kasparov Theory
No full textThis thesis presents a number of new approaches to the treatment of group actions in unbounded Kasparov theory. Its results are motivated by the desire to incorporate into spectral noncommutative geometry several formerly problematic examples. We extend unbounded Kasparov theory to encompass conformal group and quantum group equivariance. We use this, along with tools from geometric group theory, to study the geometry of group C*-algebras and Fell bundles. We prove a nontriviality result for Kasparov modules built from group actions on CAT(0) spaces. We also study the geometry of group extensions using the unbounded Kasparov product.We introduce a new multiplicative perturbation theory that enables us to treat conformal actions on both manifolds and noncommutative spaces. As examples, we present unbounded representatives of Kasparov’s γ-element for the real and complex Lorentz groups and display the conformal (2)-equivariance of the standard spectral triple of the Podleś sphere. In pursuing descent for conformally equivariant cycles, we are led to a new framework for representing Kasparov classes. Our new representatives, conformally generated cycles, are unbounded, possess a dynamical quality, and also include known twisted spectral triples. We define an equivalence relation on these new representatives whose classes form an abelian group surjecting onto KK-theory.We also develop a new framework for the treatment of parabolic features in noncommutative geometry, in the form of the notion of tangled cycle. Tangled cycles incorporate anisotropy by replacing the unbounded operator in a higher order cycle that mimics a Dirac operator with several unbounded operators mimicking directional Dirac operators, allowing for varying and dependent orders in different directions, controlled by a weighted graph. Our main examples of tangled cycles fit into two classes: hypoelliptic spectral triples constructed from Rockland complexes on parabolic geometries and Kasparov product spectral triples for nilpotent group C*-algebras and crossed product C*-algebras of parabolic dynamical systems.</p