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Extracellular electron transfer by the cultured coral photosymbiont Symbiodinium microadriaticumNARA Subscribed
Photosynthetic microorganisms may show extracellular electron transfer (EET), in which some of the electrons generated by photosynthesis or respiration are lost from the cell. Most studies have focussed on cyanobacteria, with very few on eukaryotic algae. Here we demonstrate EET from the eukaryotic dinoflagellate alga Symbiodinium microadriaticum , a species that can form symbiosis with corals and other Cnidaria. We show that...
Taking Genomics Outdoors: Linking Local Adaptation, Trait Variation and Gene Expression in Grass Ecotypes Across a Rainfall GradientNARA Subscribed
With increasing droughts, understanding local adaptation and drought tolerance in ecologically dominant species is crucial for enhancing ecosystem resilience. We leveraged a long‐term reciprocal garden to assess local adaptation and drought responses in Andropogon gerardi , a foundation grassland species in the US Great Plains. Our objectives were to identify adaptive traits, explore gene expression responses across a rainfall...
Warming Temperatures to Expand Spruce Beetle Outbreak Distribution in Northern but Not Southern Picea Forests of Western North AmericaNARA Subscribed
Aim The biogeography and distribution of irruptive forest insect herbivores are driven by population level responses to host availability, temperature, and precipitation. Because the irruptive dynamics of tree‐killing insects such as spruce beetle are regulated by climate, it is imperative to quantify biogeographic drivers and limiters to develop informed predictions and forecasts of future outbreaks. Here, we: (1) identify su...
The frequency and chemical phenotype of neighboring plants determine the effects of intraspecific plant diversityNARA Subscribed
Associational effects, whereby plants influence the biotic interactions of their neighbors, are an important component of plant–insect interactions. Plant chemistry has been hypothesized to mediate these interactions. The role of chemistry in associational effects, however, has been unclear in part because the diversity of plant chemistry makes it difficult to tease apart the importance and roles of particular classes of compo...
The test–retest reliability of physiological and perceptual responses during treadmill load carriageNARA Subscribed
Purpose Understanding the test–retest reliability of physiological responses to load carriage influences the interpretation of those results. The aim of this study was to determine the test–retest reliability of physiological measures during loaded treadmill walking at 5.5 km h −1 using the MetaMax 3B. Methods Fifteen Australian Army soldiers (9 male, 6 female) repeated two 12-min bouts of treadmill walking at 5.5 km h −1 in b...
A global latitudinal gradient in the proportion of terrestrial vertebrate forest speciesNARA Subscribed
Aim Global patterns in species distributions such as the latitudinal biodiversity gradient are of great interest to ecologists and have been thoroughly studied. Whether such a gradient holds true for the proportion of species associated with key ecotypes such as forests is however unknown. Identifying a gradient and ascertaining the factors causing it could further our understanding of community sensitivity to deforestation an...
The benefits of regular aerobic exercise training on cerebrovascular function and cognition in older adultsNARA Subscribed
We compared the differences in cerebrovascular and cognitive function between 13 aerobic exercise trained, older adults and 13 age-, height- and sex-matched sedentary, untrained controls. We determined whether other measures accounted for differences in cerebrovascular and cognitive function between these groups and examined the associations between these functions. Participants undertook anthropometric, mood, cardiovascular,...
There is an urgent need for countries to transition their national food and land-use systems toward food and nutritional security, climate stability, and environmental integrity. How can countries satisfy their demands while jointly delivering the required transformative change to achieve global sustainability targets? Here, we present a collaborative approach developed with the FABLE—Food, Agriculture, Biodiversity, Land, and...
Brain volume in chronic ketamine users — relationship to sub-threshold psychotic symptoms and relevance to schizophreniaNARA Subscribed
Rationale Ketamine may model aspects of schizophrenia arising through NMDA receptor activity deficits. Although acute ketamine can induce effects resembling both positive and negative psychotic symptoms, chronic use may be a closer model of idiopathic psychosis. Objectives We tested the hypotheses that ketamine users had lower brain volumes, as measured using MRI, and greater sub-threshold psychotic symptoms relative to a poly...
Test–retest reliability of arterial spin labelling for cerebral blood flow in older adults with small vessel diseaseNARA Subscribed
Cerebral small vessel disease (SVD) is common in older people and is associated with lacunar stroke, white matter hyperintensities (WMH) and vascular cognitive impairment. Cerebral blood flow (CBF) is reduced in SVD, particularly within white matter. Here we quantified test–retest reliability in CBF measurements using pseudo-continuous arterial spin labelling (pCASL) in older adults with clinical and radiological evidence of S...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Palmitic Acid and Oleic Acid Differently Modulate TLR2-Mediated Inflammatory Responses in Microglia and MacrophagesNARA Subscribed
The relationship between systemic immunity and neuroinflammation is widely recognised. Infiltration of peripheral immune cells to the CNS during certain chronic inflammatory states contributes significantly to neuropathology. Obesity and its co-morbidities are primary risk factors for neuroinflammatory and neurodegenerative conditions, including Alzheimer’s disease (AD). Dietary fats are among the most proinflammatory componen...
Common, low-frequency, rare, and ultra-rare coding variants contribute to COVID-19 severityNARA Subscribed
The combined impact of common and rare exonic variants in COVID-19 host genetics is currently insufficiently understood. Here, common and rare variants from whole-exome sequencing data of about 4000 SARS-CoV-2-positive individuals were used to define an interpretable machine-learning model for predicting COVID-19 severity. First, variants were converted into separate sets of Boolean features, depending on the absence or the pr...