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Reflections on challenges and opportunities in attempting a clinical academic career
No full textThis article explores the perspectives and experiences of trainee, trainee-adjacent and early career psychiatrists who are attempting a clinical academic career. Collective views are grouped under five themes – Fostering Agency, Barriers and Setbacks, Mentors and Self Care, Saying Yes to Serendipity, and Stability and Time. Recommendations for those at an individual, clinical service, and College level are considered.</jats:p
Topological Recursion, Deformations, and Interlacing
No full textThe theory of topological recursion has proven to be a powerful unifying force in the
areas of enumerative geometry, integrability, matrix models, enumerative combinatorics,
and mathematical physics more generally. As a “classical” example, using the Weingarten
calculus for unitary groups, the large N asymptotics of the Harish-Chandra–Itzykson–Zuber
matrix integral was shown to recover the monotone Hurwitz numbers, which are
governed by the Chekhov–Eynard–Orantin topological recursion. This result can
be generalised to a broader correspondence between weighted Hurwitz numbers, the
Kadomtsev–Petviashvili hierarchy and the topological recursion, facilitated by the
representation theory of the symmetric groups.
Motivated by the above example, this thesis concerns itself with the large N asymptotics of
matrix integrals over certain quotients of the unitary and orthogonal groups, which may
be identified with complex and real Grassmannians, respectively. By interpolating between
the asymptotics of the unitary and orthogonal integrals via a parameter b, a two-parameter
deformation of the monotone Hurwitz numbers is obtained and shown to be an example
of a weighted b-Hurwitz number. As a consequence of this interpolation, a family of
b-dependent operators arise from a purely combinatorial construction, which appear to
mimic the behaviour of the Jucys–Murphy elements in the symmetric group algebra and
recover them when b = 1. The aforementioned correspondence with topological recursion
for general bis not yet explicit – promising developments such as the refined topological
recursion of Kidwai–Osuga are discussed. To conclude, conjectures are made on
the root structure of the two-parameter deformation of the monotone Hurwitz numbers –
namely, that at b = 0, their roots are real and interlace. It is suggested that this observation
may be a general phenomenon, arising from the topological recursion applied to certain
families of spectral curves
Problematising the Will to Intervene: Discourses on Alternative Solutions to Prison
No full textThis article explores a paradox in discourse on alternatives to prison: in trying to minimise the prison, its functions seep further into society. Prison and the pursuit of alternatives involve two suppositions: some populations need control, and some portion of the population constitutes a legitimate enforcer of control. The implications of this paradox are explored via community surveillance technology and justice reinvestment, two recent ideas to curtail the prison. The piece is indebted to Foucault, especially the attention he draws to the problem of the legitimacy to punish, and radical constructivist logic, which encourages interrogation of the cultural frameworks upon which social practices emerge. As critical scholars sympathetic to prison abolition, what follows is a reflexive gesture. It asks if critical approaches harbour categories that are hard to reconcile with political projects of decomposing the prison
Evaluating the Feasibility of the Gastrointestinal Dysfunction Score (GIDS) in a New Zealand Intensive Care Unit: A Comparison of Objective and Subjective Assessment Methods
No full textBackground: Gastrointestinal dysfunction (GD) is a frequent clinical challenge among critically ill patients, associated with adverse outcomes, such as longer Intensive Care Unit (ICU) stays and increased mortality. However, most methods to assess GD are subjective. Standardised, objective tools like the Gastrointestinal Dysfunction Score (GIDS) are needed to improve gastrointestinal assessment in the ICU.
Objective: To compare intensivists' subjective GD assessments with nurses' and the researchers' objective GIDS assessments, evaluate GIDS consistency between nurses and the researcher, and assess GIDS feasibility and acceptability among ICU nurses.
Method: This pilot prospective study was conducted in a single ICU. It involved 30 patients, 20 ICU nurses, and nine intensivists over a two-week period. Data collection involved GIDS assessments by the investigating researcher and nurses, subjective gut function ratings by intensivists using a 5-point Likert scale, and a 4-question feasibility survey completed by nurses. Data were analysed using SPSS for quantitative statistics and NVivo for thematic analysis of qualitative survey responses.
Results: Agreement between nurses' and researchers' GIDS scores was fair to substantial (κ=0.714, p=<0.001), but both showed discrepancies when compared to intensivists' subjective ratings of GD. Nurses indicated that the GIDS tool was easy to use and feasible but lacked awareness and understanding about the tool and GI assessment. Nurses identified time constraints, workflow integration, education and training needs as potential implementation barriers. The qualitative analysis highlighted further concerns about increased workloads and the tool's limited applicability to diverse patient conditions.
Conclusion: This pilot study supports the potential use of the GIDS as a standardised tool for objective GD assessment in the ICU. While further validation is required before formal tool adoption, the GIDS shows promise in addressing inconsistencies in current GD assessment practices. Although not without its limitations, the GIDS represents a step, alongside other non-invasive methods, to improving overall gut assessment in the future. Successful implementation will require targeted education to overcome adoption challenges. The findings from this study provide a foundation for further large-scale studies needed to improve GD assessment in critical care settings
Information Technology Pioneers of Aotearoa New Zealand
No full textThis article traces the history of New Zealand's information technology innovators from the late 19th century until the arrival of the first stored-program computers in 1960, a history that parallels the country's evolution towards a modern economy. Starting in 1879, various individuals deployed simple racetrack totalisators. At the turn of the century, Donald Murray became a leading figure in automatic telegraphy. As punched card usage blossomed in the 1920s and 1930s, Leslie Comrie moved to the U.K., where he actively promoted scientific computation. By the 1950s, the economy had matured to the point where government, businesses and universities were eager to join the computer age. We conclude with the stories of some of the first New Zealanders to write software during this booming computer age, and we were privileged to interview three of them
Local scour mechanism around monopile foundations subjected to cyclic lateral vibration
No full textOffshore wind turbines usually experience large numbers of lateral cyclic vibrations induced by winds and waves in their service life. The local scour process and vibrations will likely occur simultaneously in the field, threatening the stability of the monopile foundation of Offshore Wind Turbines (OWTs). However, traditional studies mainly focus on local scour around static monopile foundations. The local scour mechanism around monopile foundations subjected to cyclic lateral vibration remains unclear.
To address this research gap, the study reported herein was undertaken. The study is an experimental investigation of motions of sand particles around vibrating monopile foundations and subsequent examination of the local scour mechanism under different hydrodynamic conditions.
Firstly, a sandbox experimental system was developed to analyse the characteristics of sand motion under cyclic lateral vibration, considering factors such as backfilling sand and saturated conditions. Subsequent experiments focused on the local scour process under current-only and combined wave-current conditions.
In current-only conditions, the local scour development characteristics and equilibrium scour depth in different flow intensities are analysed. Additionally, the influence of vibration direction on the local scour is investigated.
Lastly, the local scour mechanism around monopile foundations subjected to cyclic lateral vibration under combined wave-current conditions is investigated. The coupling effects of vibration, waves, and currents on local scour process and equilibrium scour depth around the foundation are studied. To quantify the hydrodynamic intensity induced by waves and currents, considering the influence of sediment grain size, a new dimensionless parameter named the undisturbed friction velocity-based Froude number (Fr*) is proposed. Furthermore, equations for predicting equilibrium scour depth around vibrating monopile foundations under current-only and combined wave-current conditions are proposed.
In summary, this thesis represents a pioneering effort to systematically investigate the interaction between piles and soil, as well as the local scour mechanism around monopile foundations subjected to cyclic lateral vibration under complex environmental conditions. The findings significantly enhance our understanding of the local scour issues surrounding monopile foundations for OWTs and hold promise for improving foundation design and enhancing scour protection measures in offshore engineering practices
Supporting choice, preventing harm: Social workers’ knowledge gaps and ethical challenges with assisted dying in Aotearoa New Zealand
No full textINTRODUCTION: This study is the first of its kind to explore social workers’ perspectives on assisted dying following the legislation of the End of Life Choice Act 2019 in Aotearoa New Zealand. The topic is ethically complex and legally regulated, making social workers’ perspectives particularly valuable since they may increasingly engage with people facing end-of-life decisions in settings like hospitals, hospices, aged care facilities, and palliative care programmes.
METHOD: Data were collected through an anonymous online qualitative survey from September to December 2023, capturing a diverse range of views from 120 social workers in Aotearoa New Zealand.
FINDINGS: Three themes were constructed from the data using Proudfoot’s (2023) hybrid thematic coding strategy: 1) “some semblance of choice”: navigating client autonomy, 2) “be careful”: managing ethics, coercion and risk, and 3) “just my own research”: limited knowledge and training. Participants noted the tension between upholding clients’ rights to choose while being mindful of personal and external pressures that may influence decisions, especially among vulnerable groups. Participants also expressed a need for more precise guidelines and more training to handle the ethical dilemmas posed by assisted dying in a manner that is thoughtful, competent, and appropriate.
IMPLICATIONS: These findings suggest that social workers play a crucial role in mediating between client autonomy and protection. By understanding the ethical challenges and systemic barriers in assisted dying, social workers can better advocate for transparent policies and improved training, equipping them to provide better support to clients in their end-of-life decisions
Pharmacokinetic and Pharmacodynamic Modeling of Clonidine and Midazolam for Sedation in Pediatric Intensive Care
No full textBackground: Clonidine and midazolam are routinely used in the pediatric intensive care unit for pain and sedation management, but target concentration and optimal dose are poorly defined for both drugs. The CloSed study is a multicenter, double‐blind, randomized, active‐controlled noninferiority trial with a 1:1 randomization between clonidine and midazolam.
Aims: Data from the prematurely terminated CloSed trial were used to study the population pharmacokinetic–pharmacodynamic relationships for clonidine and midazolam to inform the optimal use of both drugs in mechanically ventilated children.
Methods:Twenty‐eight patients (0–6 years) were included; 13 received midazolam, and 15 received clonidine. Morphine was administered to all patients as background analgesia. A total of 317 and 306 observed COMFORT‐B scores for midazolam and clonidine, respectively, were available to build the pharmacokinetic–pharmacodynamic model. Pharmacokinetic models were developed using findings from previously published pharmacokinetic studies to augment the trial data. A one‐compartment model described clonidine pharmacokinetics, while a single compartment for midazolam and its metabolite described its pharmacokinetics. A joint inhibitory sigmoid model that included a postanesthesia effect was used to describe the concentration–effect relationship, using the COMFORT‐B score as the pharmacodynamic endpoint.
Results: The final models adequately described the observed data. Simulations based on the final models showed that a clonidine dose of 4 μg/kg loading dose followed by a 3 μg/kg/h infusion, and a midazolam dose of 200 μg/kg loading dose followed by a 200 μg/kg/h infusion would be required to achieve adequate sedation.
Conclusion: The CloSed data suggest that higher doses of clonidine and midazolam than are commonly used in clinical practice should be considered to provide adequate sedation in critically ill children
Context-Aware Multimodal Human Activity Recognition Using Graph Convolutional Networks
No full textHuman activity recognition (HAR) in real-world environments is challenging due to sensor noise, environmental variations, and subject-specific differences. Accurate recognition is crucial for applications such as assistive technologies and smart homes. While traditional machine learning and deep learning models, including CNNs and RNNs, perform well in controlled settings, they often fail to generalize to real-world scenarios. A major limitation is their lack of contextual understanding, which weakens their ability to model activity relationships. Additionally, hyperparameter tuning is inefficient, leading to suboptimal performance. Some studies have applied metaheuristic optimization to address these issues, but results have been inconsistent, and few have leveraged the contextual learning capabilities of GCNs to improve HAR performance.
To address these challenges, we propose a hybrid graph convolutional network (GCN) framework. This framework combines CNN and GCN to enhance context learning and improve hyperparameter optimization. Our approach leverages the structural strengths of GCNs to capture activity dependencies while improving feature extraction and representation learning. Experimental results on controlled and in-the-wild datasets show that our CNN-GCN hybrid model outperforms baseline models and GCN model. Especially in real-world scenarios that are difficult to solve with traditional methods, the accuracy and speed of training have been improved. Although the improved contextual modeling in our framework has improved on several evaluation criteria, metaheuristic optimization has not produced the expected benefits. This study highlights the importance of context-aware learning in GCN-based HAR models and offers a more robust solution for real-world applications. The findings contribute to advancing multimodal activity recognition and provide insights for researchers and practitioners working in dynamic environments
Investigation of the Impact of TMAO and Other Organic Cosolutes on NMR Chemical Shift Referencing
No full textIn response to environmental stresses, organisms may accumulate a variety of small organic
compounds intracellularly to help maintain homeostasis. Trimethylamine N-oxide (TMAO) is
one such compound, that is accumulated in marine organisms for a range of reasons. Most
notably, TMAO is a potent and generic protein stabiliser, which has often been employed to
study protein stability in vitro, using techniques that include solution nuclear magnetic
resonance (NMR) spectroscopy. Here I consider the implications of adding high
concentrations of TMAO and other organic cosolutes for NMR chemical shift referencing.
Addition of organic cosolutes can change the magnetic susceptibility of the solution and can
potentially also alter the nuclear shielding of both water, and standard reference compounds,
such as 2,2-dimethylsilapentane-5-sulfonic acid (DSS) via strong local interactions. Such
effects can complicate the measurement and interpretation of NMR chemical shifts; however,
the magnitude of these effects has not been systematically investigated. In this thesis, I report
physical measurements on TMAO solutions which will help overcome some of the practical
difficulties of working with this very hygroscopic compound. Subsequently, investigating
TMAO and several other common biological cosolutes (trehalose, betaine, and urea), I report
1H NMR measurements on DSS/water/cosolute and DSS/water solutions in a coaxial tube
system with physically separated compartments. I also report measurements of the magnetic
susceptibility of the cosolute solutions. Taken together, this data allowed for quantification of
the relative changes in nuclear shielding of water and the reference compound DSS, that are
caused by the addition of cosolute. My results show that the influence of the studied cosolutes
on the nuclear shielding of DSS protons are generally quite small, though not always
inconsequential. On the other hand, the effects of these cosolutes on the nuclear shielding of
water protons are in some cases very large. This has important implications for internal and
substitution chemical shift referencing. The data presented in the thesis will allow more
quantitative analysis of data from biological NMR studies performed in the presence of
organic cosolutes