Syncope in a young man: Role of Purkinje fibres in idiopathic ventricular fibrillation

A young man suffered cardiac arrests with polymorphic ventricular tachycardia (PVT) and ventricular fibrillation (VF) triggered by ventricular premature contractions (PVCs). The arrhythmia was resistant to anti-arrhythmics, so after ICD implantation he underwent successful ablation of the triggering VE beat, which was pace-mapped to the left posterior hemi-fascicle. We review the evidence for the role of the Purkinje network in the initiation and maintenance of PVT and VF, postulating a channelopathy as a possible underlying cause, and provide recommendations for PVC ablation

Coronavirus: COVID-19 transmission in Pacific small island developing states

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Background: Pacific Small Island Developing States (SIDS) have health care systems with a limited capacity to deal with pandemics, making them especially vulnerable to the economic and social impacts of the coronavirus (COVID-19). This paper examines the introduction, transmission, and incidence of COVID-19 into Pacific SIDS. Methods: Calculate the rate of transmission (the average number of new cases per day between the first recorded case and the most recent day) and connectivity (daily direct flights to the leading airport in each selected island group) using flight history and COVID-19 transmission data. Results: Correlational analyses show that connectivity is positively related with (a) first-case dates and (b) spread rate in Pacific SIDS. Conclusion: Connectivity plays a central role in the spread of COVID-19 in Pacific SIDS. The continued entry of people was a significant factor for spread within countries. Efforts to prevent transmission by closing borders reduced transmission but also created significant economic hardship because many Pacific SIDS rely heavily on tourism and international exchange. The findings highlight the importance of exploring the possibility that the COVID-19 spread rate may be higher than official figures indicate, and present pathways to mitigate socio-economic impacts. The practical implications of the findings reveal the vulnerability of Pacific SIDS to pandemics and the key role of connectivity in the spread of COVID-19 in the Pacific region

Between tinkering and transformation: A contemporary appraisal of climate change adaptation research on the world's islands

Islands are at the center of discourses on climate change. Yet despite extensive work on diverse island systems in a changing climate, we still lack an understanding of climate change-related responses amongst islands and what shifting from what might be called “tinkering” (perhaps heat warnings) to “transformational” adaptation (perhaps relocation) means for these vastly different landmasses which are often grouped together by default. Through a systematic review of the climate change adaptation scientific literature, this paper critically reflects on how considering islands as a homogenous ensemble and the use of buzzwords such as “transformational adaptation” may be problematic for diverse island realities under climate change. Our findings show that the adaptation evidence base actually provides literature on contrasting island types and cultural and political contexts, including Small Island Developing States as well as other island territories. This study finds research gaps with respect to regions (e.g., South America, Africa, and Mediterranean) and that there is overall both little evidence of and a lack of context-specific definitions of transformational adaptation in island contexts. The adaptation literature does not yet fully reflect the experiences or needs of islands regarding transitions and transformations throughout history

The Spread of Fecally Transmitted Parasites in Socially-Structured Populations

Mammals are infected by a wide array of gastrointestinal parasites, including parasites that also infect humans and domesticated animals. Many of these parasites are acquired through contact with infectious stages present in soil, feces or vegetation, suggesting that ranging behavior will have a major impact on their spread. We developed an individual-based spatial simulation model to investigate how range use intensity, home range overlap, and defecation rate impact the spread of fecally transmitted parasites in a population composed of social groups (i.e., a socially structured population). We also investigated the effects of epidemiological parameters involving host and parasite mortality rates, transmissibility, disease–related mortality, and group size. The model was spatially explicit and involved the spillover of a gastrointestinal parasite from a reservoir population along the edge of a simulated reserve, which was designed to mimic the introduction pathogens into protected areas. Animals ranged randomly within a “core” area, with biased movement toward the range center when outside the core. We systematically varied model parameters using a Latin hypercube sampling design. Analyses of simulation output revealed a strong positive association between range use intensity and the prevalence of infection. Moreover, the effects of range use intensity were similar in magnitude to effects of group size, mortality rates, and the per-contact probability of transmission. Defecation rate covaried positively with gastrointestinal parasite prevalence. Greater home range overlap had no positive effects on prevalence, with a smaller core resulting in less range overlap yet more intensive use of the home range and higher prevalence. Collectively, our results reveal that parasites with fecal-oral transmission spread effectively in socially structured populations. Future application should focus on parameterizing the model with empirically derived ranging behavior for different species or populations and data on transmission characteristics of different infectious organisms

Tpeak-Tend, Tpeak-Tend/QT ratio and Tpeak-Tend dispersion for risk stratification in Brugada Syndrome:A systematic review and meta-analysis

Background: Brugada syndrome is an ion channelopathy that predisposes affected subjects to ventricular tachycardia/fibrillation (VT/VF), potentially leading to sudden cardiac death (SCD). Tpeak-Tend intervals, (Tpeak-Tend)/QT ratio and Tpeak-Tend dispersion have been proposed for risk stratification, but their predictive values in Brugada syndrome have been challenged recently. Methods: A systematic review and meta-analysis was conducted to examine their values in predicting arrhythmic and mortality outcomes in Brugada Syndrome. PubMed and Embase databases were searched until 1 May 2018, identifying 29 and 57 studies. Results: Nine studies involving 1740 subjects (mean age 45 years old, 80% male, mean follow-up duration was 68 ± 27 months) were included. The mean Tpeak-Tend interval was 98.9 ms (95% CI: 90.5-107.2 ms) for patients with adverse events (ventricular arrhythmias or SCD) compared to 87.7 ms (95% CI: 80.5-94.9 ms) for those without such events, with a mean difference of 11.9 ms (95% CI: 3.6-20.2 ms, P = 0.005; I2 = 86%). Higher (Tpeak-Tend)/QT ratios (mean difference = 0.019, 95% CI: 0.003-0.036, P = 0.024; I2 = 74%) and Tpeak-Tend dispersion (mean difference = 7.8 ms, 95% CI: 2.1-13.4 ms, P = 0.007; I2 = 80%) were observed for the event-positive group. Conclusion: Tpeak-Tend interval, (Tpeak-Tend)/QT ratio and Tpeak-Tend dispersion were higher in high-risk than low-risk Brugada subjects, and thus offer incremental value for risk stratification

Late Holocene sea-level changes and vertical land movements in New Zealand

Coasts in tectonically active regions face varying threat levels as land subsides or uplifts relative to rising sea levels. We review the processes influencing relative sea-level change in New Zealand, and the geological context behind ongoing land movements, focussing on major population centres. Whilst Holocene sea levels have been reconstructed using a variety of techniques, recent work uses salt-marsh microfossil assemblages to reconstruct relative sea-level changes over the past few centuries. For the twentieth century, these proxy-based studies often show enhanced rates of sea-level rise relative to tide-gauge observations. The effects of tectonic subsidence must be considered, alongside vertical and dating uncertainties in the sea-level reconstructions. Global Positioning Systems (GPS) observations for the past few decades show that vertical land movement (VLM) may be influencing rates of relative sea-level rise. However, the short period of GPS observations, during which trends and rates have varied at some localities, raises questions over the longer-term contribution of VLM to sea-level change over the past few centuries and for future projections. We argue that high-resolution palaeo-sea-level reconstructions from salt-marsh sedimentary sequences can help to answer these questions regarding the interplay between sea-level change and VLM at key locations

Resilience in education: An example from primary school in Fiji and technical vocational education and training

In the Pacific, the capacity of curriculum writers for integrating the content of climate change into their curricula and/or taught Resilience [Climate Change Adaptation (CCA) & Disaster Risk Reduction (DRR)] in education is limited. This paper described the findings of a 2018 study on the integration of climate change into primary and secondary schools’ curricula and taught resilience in education in TVET. It involves teachers (n = 30) from Kadavu and Levuka islands, curriculum writers and editors from the Ministry of Education, GIZ, SPC, and USP—in Fiji. An exploratory design was used to explore the curricula for Fiji and the EU PacTVET project at SPC. Information was collected from workshops and training events, interviews and project documents. Using BEKA (Benchmarking, Evidencing, Knowing, Applying) and the concept of ako (e.g. to study or educate), a model of climate change and resilience in education was designed as part of this research to help Pacific schools with their curricula. These results indicate how behavioural changes may shape Resilience, thus placing them in a better position to achieve the UNFCCC, the SDGs, the Sendai Framework and the Framework for Resilient Development in the Pacific (FRDP) targets and objectives by 2030 and beyond

Pacific island regional preparedness for El Niño

The El Niño Southern Oscillation (ENSO) cycle is often blamed for disasters in Pacific island communities. From a disaster risk reduction (DRR) perspective, the challenges with the El Niño part of the ENSO cycle, in particular, are more related to inadequate vulnerability reduction within development than to ENSO-induced hazard influences. This paper analyses this situation, filling in a conceptual and geographic gap in El Niño-related research, by reviewing El Niño-related preparedness (the conceptual gap) for Pacific islands (the geographic gap). Through exploring El Niño impacts on Pacific island communities alongside their vulnerabilities, resiliences, and preparedness with respect to El Niño, El Niño is seen as a constructed discourse rather than as a damaging phenomenon, leading to suggestions for El Niño preparedness as DRR as part of development. Yet the attention which El Niño garners might bring resources to the Pacific region and its development needs, albeit in the short term while El Niño lasts. Conversely, the attention given to El Niño could shift blame from underlying causes of vulnerability to a hazard-centric viewpoint. Instead of focusing on one hazard-influencing phenomenon, opportunities should be created for the Pacific region to tackle wider DRR and development concerns