University of Otago

The effects of climate change and human pollution on ecosystems worldwide are becoming increasingly apparent and are expected to increase disease susceptibility, which could have devastating impacts when keystone species are affected. Habitat-forming kelps are vital ecosystem engineers in marine ecosystems. In the Southern Hemisphere, bull kelps (Durvillaea) shape shallow marine ecosystems, providing habitat, food and shelter for numerous marine organisms. Despite their ecological importance, little is known about kelp diseases and their drivers. Here, we survey various blemishes, potentially indicative of disease, in New Zealand Durvillaea poha populations. Generalized linear mixed modelling was used to explore which environmental and anthropogenic factors might affect blemish prevalence. Our analysis indicated that blemish prevalence may be influenced by combinations of external factors, such as the distance to sewage and river outlets and predominant land use. Our study lays the groundwork for mapping blemishes and their drivers in large, brown macroalgae, an essential step in exploring kelp diseases, improving predictions and protection of marine ecosystems.

Near-extinction events impose severe genomic bottlenecks that can have lasting fitness consequences, yet the specific mechanisms involved remain poorly understood. 'Alalā, the endemic Hawaiian crow, narrowly avoided extinction when a conservation breeding program was founded from just nine individuals. Although the breeding program has since recovered to ~120 birds, it remains plagued by egg hatching failure rates >50%. To investigate the impacts of this bottleneck on hatching failure and other fitness components, we generated a chromosome-level reference genome and resequenced 175 individuals, including 78 deceased embryos. Although long runs of homozygosity (ROH) >1Mb are abundant in 'Alalā (mean FROH=0.32), associations between FROH and measures of survival and reproduction, including egg failure, were weak or nonexistent. Instead, we identify two recessive lethal haplotypes that together account for ~20% of all hatching failures and have persisted in the population at high frequency (15-25%), hinting at impaired purifying selection. Eco-evolutionary simulation models demonstrate that these limited impacts of ROH and elevated recessive lethal allele frequencies are expected for a species that has endured a severe population bottleneck and exhibits modest levels of non-ROH heterozygosity. Our findings suggest that elevated recessive allele frequencies may be a broadly important consequence of population bottlenecks.

Non-pharmaceutical interventions (NPIs) are central to mitigating COVID-19 and influenza, yet comparative economic evaluations remain scarce. This systematic review assessed the cost effectiveness and reporting quality of NPI evaluations across both diseases. The study was registered with PROSPERO (CRD42024552613). Following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines, we searched five medical (PubMed, Scopus, EMBASE, CINAHL, and EconLit) and four health technology assessment databases (NHS HTA, CRD DARE, NHS EED, and INAHTA) up to December 2025, including only full economic evaluations. The search strategy incorporated four domains-'influenza,' 'COVID-19,' 'NPIs,' and 'economic evaluation'-and was guided by the WHO NPI framework, encompassing five domains: personal protective, environmental, physical distancing, travel-related, and educational measures. Reporting quality was assessed using the Consolidated Health Economic Evaluation Reporting Standards 2022 (CHEERS 2022) checklist. Thirty-three studies (13 influenza, 20 COVID-19), predominantly from high-income countries, were included. School closures, the most frequently evaluated NPI, were generally not cost effective except during severe pandemics or bundled with other measures. Workforce and business closures were cost effective only in high-severity influenza, with inconsistent findings for COVID-19. Social distancing was cost effective for COVID-19 but not for H1N1 influenza. Isolation, lockdowns, and travel restrictions were cost effective only when implemented early. Face masks and hand hygiene, assessed solely for COVID-19, were generally cost effective when implemented alongside other measures. The median CHEERS score was 75.0%, with one study rated excellent. Our review highlights heterogeneity in cost effectiveness by pandemic severity, intervention type, bundling of measures, and timing. Strategies that combined low-cost NPIs like masks or hand hygiene demonstrated better value, while socially disruptive measures like school and business closure incurred high costs with inconsistent cost-effectiveness outcomes. Integration with vaccines or antivirals further enhanced cost effectiveness. Evidence gaps include the scarcity of evaluations from low-resource settings and variability in country-specific value thresholds. Addressing these gaps is essential for guiding efficient and cost-effective pandemic preparedness.

Objective To assess the diagnostic accuracy and reliability of orthopantomogram (OPG) compared to cone beam computed tomography (CBCT) in evaluating the mandibular buccal shelf anatomy, with specific emphasis on the proximity to the inferior alveolar nerve canal (IANC), across various skeletal malocclusions and vertical growth patterns. Methods A cross-sectional study with a retrospective design was conducted using OPG and CBCT images of 90 patients obtained prior to treatment, stratified based on skeletal malocclusion into Class I, II, and III groups ( n = 30 each), and further subdivided based on facial divergence (hypodivergent, normodivergent, hyperdivergent). Linear measurements extending from the cementoenamel junction (CEJ) to the superior margin of the IANC were obtained at eight predefined anatomical landmarks. Independent t -test and one-way analysis of variance were used for data analysis, considering P < .05 as statistically significant. Results OPG and CBCT measurements showed no statistically significant differences across all malocclusion and growth patterns ( P > .05). A consistent decrease in CEJ to IANC distance from the mesial CEJ of the first molar to the distal CEJ of the second molar was observed, most pronounced in hyperdivergent individuals. Class III hypodivergent subjects exhibited the greatest bone height (21.19 ± 1.28 mm), whereas Class II hyperdivergent individuals showed the lowest bone height (15.68 ± 1.72 mm), indicating a closer proximity of the IANC. Conclusion OPG is a reliable alternative to CBCT for buccal shelf assessment, offering reduced radiation exposure and cost. Anatomical variations across skeletal and vertical growth patterns significantly impact screw placement safety, emphasizing the need for individualized site selection based on malocclusion and divergence patterns.

Salto: Gesamtband inkl. Lernwortschatz. Lehrwerk für Latein als zweite Fremdsprache (H.) Haselmann, (F.) Hennerici, (P.) Jitschin, (G.) Laser, (S.) Losch. Pp. 304 + 46, colour ills, colour maps. Göttingen: Vandenhoeck & Ruprecht, 2021. Cased, €34. ISBN: 978-3-525-71781-3 and 978-3-525-71782-0.

High-value feedback is essential for the successful development of medical physics trainees (registrars) as they complete their clinical training. In this education note, we present an overview of a small education intervention we implemented in our hospital to encourage feedback conversations, one of the principles of high-value feedback. Our intervention was based on the concepts of 'assessment for learning' and 'programmatic assessment'. This intervention encourages registrars to take ownership of the feedback process associated with each learning outcome assessment. Registrars are encouraged to complete and document a self-assessment of their performance, before seeking feedback from their trainer. We modified an assessment template to support this process. This new approach appears to have resulted in higher quality feedback conversations between registrars and trainers. Additionally, trainers have benefited from the registrars completing the majority of the assessment template, thus reducing their workload. Whilst this approach has increased the workload for registrars, we believe this has benefits for their learning. We hope other centres can learn from our experience and may consider how they can adopt a similar process for their setting.