The trials and tribulations of conducting an m-health pilot randomized controlled trial to improve oral cancer therapy adherence: recommendations for future multisite, non-drug clinical trials

Abstract Objective Integrating mobile phone-based health (m-health) interventions into healthcare systems is one solution to improve access to services for the growing number of patients with chronic illness. Practical challenges such as poor recruitment and inadequate resource allocation can hamper the assessment of such interventions with clinical trial methodology. This paper highlights the challenges encountered during a pilot randomized controlled trial of an m-health medication adherence intervention and offers recommendations for future multi-site, non-drug clinical trials. Results Eighteen patients were recruited to the study; eight were randomly allocated to the intervention arm. Intervention participants responded to their daily medication-reminder text messages, indicating that medication had been taken or not, and nurses were able to organize their calls around their workload. The trial closed prematurely primarily due to inadequate numbers of eligible patients; however, other potentially resolvable feasibility issues were identified. These included lack of infrastructure at study sites, poor screening data acquisition and management processes, and inexperience in conducting supportive care trials at participating sites. M-health intervention trials are designed to inform implementation of best supportive care practice. Adequate skills and infrastructure are research prerequisites that require careful consideration and sufficient investment for the successful execution of multi-site supportive care trials. Trial registration Australian and New Zealand Clinical Trials Register: ACTRN1261200063586

Island characteristics and sampling methodologies influence the use of stable isotopes as an ecosystem function assessment tool

Monitoring seabird-derived nutrients on islands following invasive mammal eradications may provide a useful, cost- and time-efficient indication of the recovery of ecosystem function; however, the technique has only been investigated on environmentally similar islands. How seabird-derived nutrients recover on islands with different characteristics, and how differences in sampling regimes affect results is poorly understood. To determine how different island characteristics (size, geographic location and invasion history) and aspects of the sampling regime (sample collection year, season and intra-island location) influence seabird-derived nutrients we collated nitrogen stable isotope (δ15N) data from three ecosystem components (soil, plants and spiders), collected on 28 islands around New Zealand. We investigated which variables best predict δ15N using linear-mixed effects models. Accounting for these variables and using still-invaded and never-invaded islands as controls for recovery, we then investigated changes in δ15N on islands at different stages following invasive mammal eradication. Island size, invasion history and the presence of seabirds in the direct vicinity of a sampling location all influenced δ15N. After accounting for these variables, δ15N increased with time since eradication in soils, plants and spiders, though there was still some variation that our chosen variables could not explain. This study demonstrates the importance of considering island characteristics and sampling methods when assessing seabird-derived nutrient recovery and highlights the need for additional targeted sample collection on islands to help separate out the effects of time since eradication and other confounding variables affecting δ15N. Improved understanding of these factors will be prerequisite for furthering this technique as a useful addition to the post-eradication monitoring tool kit.</p

Temporal and spatial variability in stable isotope values on seabird islands: What, where and when to sample

Invasive mammal eradications are widely used for managing island ecosystems. However, tracking the outcomes of such large-scale, whole ecosystem projects is challenging and costly, and monitoring all components of an ecosystem is near impossible. Instead, indicators of ecosystem change may provide more practical and integrated measures of ecosystem response to eradications. As high-order marine predators, seabirds subsidise island ecosystems with nutrients isotopically enriched in nitrogen. Invasive mammals have caused a global decline of seabirds on islands, reducing this nutrient subsidisation. Following eradications, nitrogen stable isotope analysis may provide a useful and resource-efficient indicator of ecosystem functional change on eradicated islands. However, isotope ratios are affected by a myriad of factors, with potential sources of variation being introduced by spatial and temporal variation in sampling, and within and between different taxa and ecosystem components. To correctly attribute isotopic change to post-eradication ecosystem function change, these confounding variables need to be understood. To address this need, we analysed stable isotopes of nitrogen in soil, plant, spider, and seabird guano samples collected at different distances from seabird colonies and at different stages of the short-tailed shearwater breeding cycle on six island sites around south-eastern Tasmania, Australia. Across these cool, temperate islands we detected no temporal variability in δ15N throughout the breeding season. However, there was notable spatial variability in δ15N values. The effects of seabird-derived nutrient subsidisation were highly localised with high δ15N values found inside seabird colonies and then rapidly decreasing from the colony boundary. Higher δ15N values also occurred in areas of higher burrow density within a colony. Variability in δ15N values also existed both within and between ecosystem components. Our results highlight the importance of context dependency when using ecological indicators and have important implications for the design, implementation and interpretation of studies employing stable isotopes as indicators for ecosystem change. We provide recommendations for designing future stable isotope studies on seabird islands.</p

One- and two-electron reductions of a bulky BODIPY compound

The redox reaction between a bulky BODIPY and a magnesium(I) reducing agent leads to the formal one-electron reduction of the BODIPY, initially generating a dipyrromethene-centred radical compound that dimerises via C–C bond formation. In contrast, reduction with magnesium anthracene leads to the formal two-electron reduction of the BODIPY, resulting in the formation of the corresponding anion

The effect of seabird presence and seasonality on ground-active spider communities across temperate islands

Seabirds influence island ecosystems through nutrient additions and physical disturbance. These influences can have opposing effects on an island's invertebrate predator populations. Spiders (order: Araneae) are an important predator in many terrestrial island ecosystems, yet little is known about how seabird presence influences spider communities at the intraisland scale, or how they respond to seasonality in seabird colony attendance.We investigated the effects of seabird presence and seasonality on ground-active spider community structure (activity-density, family-level richness, age class, and sex structure) and composition at the family-level across five short-tailed shearwater breeding islands around south-eastern Tasmania, Australia. Using 75 pitfall traps (15 per island), spiders were collected inside, near, and outside seabird colonies on each island, at five different stages of the short-tailed shearwater breeding cycle over a year. Pitfall traps were deployed for a total of 2674 days, capturing 1592 spiders from 26 families with Linyphiidae and Lycosidae the most common. Spider activity-density was generally greater inside than outside seabird colonies, while family-level richness was generally higher outside seabird colonies. For these islands, seabird breeding stage did not affect activity-densities, but there were some seasonal changes in age class and sex structures with more adult males captured during winter. Our results provide some of the first insights into the spatial and temporal influences seabirds have on spider communities. We also provide some of the first records of spider family occurrences for south-eastern Tasmanian islands, which will provide an important baseline for assessing future change.</p

Seawater carbonate chemistry and growth and grazing impact of Antarctic heterotrophic nanoflagellates

High-latitude oceans have been identified as particularly vulnerable to ocean acidification if anthropogenic CO2 emissions continue. Marine microbes are an essential part of the marine food web and are a critical link in biogeochemical processes in the ocean, such as the cycling of nutrients and carbon. Despite this, the response of Antarctic marine microbial communities to ocean acidification is poorly understood. We investigated the effect of increasing fCO2 on the growth of heterotrophic nanoflagellates (HNFs), nano- and picophytoplankton, and prokaryotes (heterotrophic Bacteria and Archaea) in a natural coastal Antarctic marine microbial community from Prydz Bay, East Antarctica. At CO2 levels ≥634 µatm, HNF abundance was reduced, coinciding with increased abundance of picophytoplankton and prokaryotes. This increase in picophytoplankton and prokaryote abundance was likely due to a reduction in top-down control of grazing HNFs. Nanophytoplankton abundance was elevated in the 634 µatm treatment, suggesting that moderate increases in CO2 may stimulate growth. The taxonomic and morphological differences in CO2 tolerance we observed are likely to favour dominance of microbial communities by prokaryotes, nanophytoplankton, and picophytoplankton. Such changes in predator–prey interactions with ocean acidification could have a significant effect on the food web and biogeochemistry in the Southern Ocean, intensifying organic-matter recycling in surface waters; reducing vertical carbon flux; and reducing the quality, quantity, and availability of food for higher trophic levels

Generating unbiased estimates of burrowing seabird populations

Maximising survey efficiency can help reduce the tradeoff between spending limited conservation resources on identifying population changes and responding to those changes through management. Burrow-nesting seabirds are particularly challenging to survey because nests cannot be counted directly. We evaluated a stratified random survey design for generating unbiased population estimates simultaneously for four petrel species nesting on Macquarie Island, Australia, where the survey cue, burrow entrances, is similar for all species. We also compared the use of design-based and model-based analyses for minimising uncertainty in estimates. We recorded 2845 Antarctic prion burrows, 306 white-headed petrel burrows and two blue petrel burrows while distance-sampling along 154 km of transects. For blue petrels and grey petrels, we completed nocturnal searches along a further 71 km and searched 249 km of tracks during follow-up ground searches. We failed to generate unbiased population estimates for two rare and localised species, blue and grey petrels, from our stratified random survey. Only for the most widespread and abundant species, Antarctic prion, did the estimate have reasonable power to detect a rapid population change. Model-based analyses of the stratified random survey data did not improve upon traditional design-based analyses in terms of uncertainty in population estimates, but they did provide useful spatial representation of current populations. Models that used the targeted survey data did not reflect current population sizes and distributions of the two rare and localised species. We found that when species ecologies, distributions and abundances vary, a multi-method approach to surveys is needed. Species with low abundance that occur patchily across large islands are likely to be best estimated using targeted surveys, whereas widespread and abundant species can be accurately and precisely estimated from randomised surveys using informative model-based analyses.</p

Assessing the utility of two-and three-dimensional behavioural metrics in habitat usage models

For deep-diving, wide-ranging marine predators, foraging behaviour is often inferred from movement data. Various metrics are used to do this, and recently, metrics have been developed that consider both horizontal movement and vertical dive behaviour to better describe the use of the 3-dimensional environment these animals inhabit. However, the efficacy of these different metrics in predicting behavioural state is poorly understood. We used first passage time (2-dimensional) and first bottom time (3-dimensional) analyses on tracks derived from satelliterelayed data loggers to quantify and determine seal behavioural state while foraging at sea. Movement and dive data were collected from 38 southern elephant seals Mirounga leonina from Macquarie and Campbell Islands (in the Pacific sector of the Southern Ocean). Using a suite of environmental variables, linear mixed-effect models were derived for the 2 broad habitats visited by the seals: shelf and open ocean. The best-fitting models for each foraging metric in each habitat were then compared using a cross validation analysis to identify which foraging metric produced the best predictions of habitat use. In shelf habitats, the 3-dimensional foraging metric provided better predictions than the 2-dimensional metric, while the 2-dimensional foraging metric resulted in the best predictive capacity in the open ocean habitats. These findings highlight the importance of considering the appropriate foraging metrics when modelling foraging behaviour.12 page(s