Understanding how microbial communities respond and adjust to ecosystem perturbation is often difficult to interpret due to multiple and often simultaneous variations in observed conditions. In this research, we investigated the microbial community dynamics of Inferno Crater Lake, an acidic geothermal spring in New Zealand with a unique thermal cycle that varies between 30 and 80 °C over a period of 40-60 days. Using a combination of next-generation sequencing, geochemical analysis and quantitative PCR we found that the microbial community composition was predominantly chemolithotrophic and strongly associated with the thermal cycle. At temperatures >65 °C, the microbial community was dominated almost exclusively by sulphur-oxidising archaea (Sulfolobus-like spp.). By contrast, at mesophilic temperatures the community structure was more mixed, comprising both archaea and bacteria but dominated primarily by chemolithotrophic sulphur and hydrogen oxidisers. Multivariate analysis of physicochemical data confirmed that temperature was the only significant variable associated with community turnover. This research contributes to our understanding of microbial community dynamics in variable environments, using a naturally alternating system as a model and extends our limited knowledge of acidophile ecology in geothermal habitats.

Objective This study aimed to study the association between maternal history of childhood adversity and blood pressure in pregnancy. Methods A total of 127 pregnant women completed measures of adverse childhood experiences (ACE) and prenatal stress between June 2015 and April 2019. At 11 weeks’ gestation (range, 6–17 weeks), we measured 24-hour ambulatory blood pressure. All women were considered to be at risk for pregnancy complications due to elevated body mass index and self-reporting snoring in pregnancy. Results Women were, on average, 30 years old (range, 19–40 years), and average (standard deviation) body mass index in this sample was 34 (7) kg/m2 (range, 27–55 kg/m2). Higher ACE scores were associated with higher nighttime blood pressure (systolic blood pressure: β = 0.23, p = .013; diastolic blood pressure: β = 0.22, p = .028). There were no significant associations between the ACE score and daytime blood pressure. Women with four or more ACEs were more likely to display nocturnal blood pressure nondipping (odds ratio = 3.97, 95% confidence interval = 1.38–11.40). Associations between ACE and nocturnal blood pressure remained significant after adjusting for symptoms of prenatal stress. Conclusions Results indicate that experiences of childhood adversity are associated with elevated nocturnal blood pressure and loss of a typical decline in blood pressure between day and night.

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