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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
Social constructions of non-invasive prenatal testing: The new right tool for the job?
No full textSince 2011, non-invasive prenatal testing (NIPT) has experienced widespread uptake around the world. While significant academic attention has been given to the clinical, legal, and ethical dimensions of NIPT, there remains little investigation of its social aspects.This thesis presents findings from a qualitative examination of NIPT in Australia. Drawing from a range of empirical data, including interviews with healthcare professionals, media coverage, advertising material, and online discussions, I analyse how understandings of NIPT’s technical, clinical, social, and ethical workability have been discursively constructed. Gaining insight into the perspectives of different social groups connected to NIPT is critical for better understanding the social shaping of new biomedical developments.I find that, while individual and collective accounts of the value of NIPT are dynamic and heterogeneous, three broad positions can be identified: that NIPT is the right tool for the right job; that NIPT is the wrong tool for the right job; and, that NIPT is the right tool for the wrong job.My analysis draws from social worlds theory to investigate who is connected to NIPT and how they talk about it. I complement this with compatible constructivist theories focussing on the intersection of people, discourse and biomedicine. I approach discourse as something that does things and through which things are done. I build on work on promissory discourses and the sociology of expectations, and explore the performative capacity of discourse to propel (and constrain) action around this new biomedical object.Building on studies on biomedicalisation, I also examine the wider sociotechnical and cultural elements conditioning and reflected in accounts of NIPT. I focus on the way biomedicalisation trends (e.g. commercialisation, technoscientisation) and countertrends, have manifested within the Australian context, highlighting the broader conditions shaping NIPT’s development. I also examine instances of resistance against biomedicalization, drawing attention to the ways in which NIPT’s use has been both practically and discursively contested.This study contributes to academic scholarship by interrogating how biomedicalisation functions outside of the US and providing new insight into how NIPT has come to be manifoldly understood within Australia.</p
Design and Control of Multifunctional Electromagnetic Dampers for Enhanced Vehicle Suspension Performance
No full textThe suspension system plays a crucial role in ensuring vehicle ride comfort, handling stability, safety, and energy efficiency, especially with the growing demands of modern passengers and drivers. This thesis develops multifunctional electromagnetic dampers (MFEMDs), an emerging suspension technology. These dampers integrate the advantages of multiple suspension types through electrical network design and control strategies. This research proposes multifunctional electromagnetic damper (MFEMD) systems and their control strategies. The goal is to achieve a balanced improvement in ride comfort, handling stability, and energy efficiency.The traditional four types of suspension systems—passive, active, semi-active, and energy regeneration suspensions—each have distinct advantages and limitations in terms of ride comfort, handling stability, road-holding performance, and energy efficiency. By combining the strengths of these systems, MFEMD systems can overcome individual disadvantages, achieving both improved energy efficiency and enhanced vibration control performance. This promising capability has driven the rapid development of multifunctional suspensions such as MFEMDs.</p
Psychiatry Unexplained
No full textThis thesis critically examines the arguments and justifications that have maintained explanation as a prime principle in psychiatric theory and practice. This thesis starts from the widespread assumption that psychiatry is a discipline with commitments to causal explanations. It examines the recent history of philosophical accounts of scientific explanations and some of the epistemic tools used in their construction; natural kinds, levels, and the reification or “ontologisation” of abstract objects. The thesis proposes a turn from explanation to understanding as the central epistemic goal in psychiatric practice. This turn leads to a pragmatic conception of psychiatry as, fundamentally, a human practice, informed by science but not a science itself.The first chapters critically examine philosophical arguments about scientific explanation in psychiatry. They focus on key ideas.The first is that psychiatry relies on forms of causal explanation found in science more generally. This starts from nomological models in which explanations are validated by natural laws or high levels of inductive support. As that nomological model was eclipsed in psychiatry and in science generally, explanation turned to mechanisms dominated by genetic, neural, and “neurocognitive” mechanisms. That has not been successfully accomplished in psychiatry. In the absence of nomological or mechanistic explanation, explanation drawn from “Natural History” has been the dominant mode as in the rest of clinical medicine.Secondly, natural history style explanation is built on “natural” kinds (e.g. species in biology, diagnoses and psychopathological classes in psychiatry). Natural kinds are assumed to conform with the causal structure of the natural world, hence they will support induction, causal scientific explanation, prediction, and intervention. Natural kinds and their consequent assumptions are examined and their validity questioned.Thirdly, psychiatry’s objects, its diagnoses, its classes, and its processes are epistemological tools. They are mistakenly assumed to have an ontological foundation in the uncertain pathological processes underlying psychiatric illnesses.More than one hundred years ago Charles Broad, writing about induction, argued that universal causation, natural kinds, and permanent substances, are interwoven as a whole and if any fails, they all fail. The preceding sections argue that they fail.This leads to the Volta or turn from a conventional epistemology of psychiatric explanation. The turn starts from philosophical critiques of the causal assumptions of scientific explanation and the dogma of empirical verification of psychiatry’s objects of explanation. It is also a turn from a narrow view of science in psychiatry as the search for cause in “biological” (brain-based) scientific knowledge toward a science that includes descriptive and historical knowledge.The turn hinges on the contrast between Explanation and Understanding in psychiatry. This starts from contrast of Erklärung as explanation that is appropriate to physical sciences and Verstehen as the understanding appropriate to “human” sciences. Jaspers brought this into psychiatry from Windelbandt and Dilthey. That contrast proves too sharp but it is a contrast, not the opposition as the Methodenstreit constructed it. The argument expands into an examination of a wider understanding of understanding but I signal here that psychiatry is a practice, not a science. This steers the development of the argument. In psychiatry, understanding yields a larger “epistemic gain” than is provided by explanation and is more tolerant of uncertain and incomplete information. Understanding is served by “thick” description and it serves comprehension rather than factual explanation and anticipation rather than prediction. Language plays an outsized role in this.The thesis argues that transparent “thick” description that serves understanding, is the primary skill in psychiatry. It comes before the opaque postulates of scientific explanation and, while description is implicated even in the most rigorous explanation, the description most useful in understanding is the sort of topographic description that gives an overview of the field of phenomena and events. Rather than opposing methods, description and explanation are better seen as poles of a virtuous hermeneutic circle, where creative attempts at explanation focuses a light on phenomena that are comprehended in description. For some time, explanation has been overvalued at the expense of description in psychiatry. In the end, narrative drawn from thick description starts to break down the distinction between explanation and description.The argument of the thesis is resolved in a coda which returns to psychiatry as an interventional practice. Practice, composed of what psychiatrists can do best, decides the domain of psychiatry. That domain is not decided by definitions or scientific delineations of mental illnesses. Psychiatric practice is informed by the human and biological sciences but it is constituted largely by the long experience of the profession transmitted in a tradition and the personal experience of the practitioner, summed as phronesis.Ultimately, there is a limit to what practice can draw from causal explanation, from scientific generalisation and from theoretical postulation, except as a spur to the reconsideration of the tradition and the careful clinical description that yields judgment and considered intervention. Finally, psychiatry is a practice that whose practitioners draw mainly from the tradition in which they are rooted. The tradition requires constant updating from the sciences, from theory but most particularly from the description and redescription of the problems the profession faces.</p