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Regional oceanographic controls on water column nitrogen fixation in northern Australian watersOA Marine
Large blooms of the diazotrophic cyanobacteria, Trichodesmium , have been reported along the north coast of Australia and are readily evident in remote sensing images. During a research cruise in November 1999, we sampled from Townsville to Broome, examined Trichodesmium population densities and their rates of carbon and N 2 fixation alongside microscopy-based cell counts of them and other cyanobacterial diazotrophs. Additiona...
Rationale Affective behavioral effects of kappa-opioid receptor (KOR) stimulation have been found to vary between the rostral and caudal nucleus accumbens (NAc) shell, but this has so far only been demonstrated in males. Objectives To examine the effects of KOR activation in subregions of the NAc shell on affective and motivated behavior in females. Methods In one group of Long-Evans rats, females were given access to 20% etha...
SNAPSHOT USA 2024: Year 6 of the Coordinated National Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multi‐contributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of speci...
Experiments on entire ecosystems have contributed knowledge on effects of atmospheric CO 2 and climate change, environmental pollutants, trophic cascades, response of fisheries to management, consumer interactions, ecosystem resilience and stability, and early warning indicators of critical transitions in ecosystem state. Rate of change in external drivers of an ecosystem such as climate warming, inflow of water or nutrients,...
Terrigenous inputs link nutrient dynamics to microbial communities in a tropical lagoonNARA Subscribed
Nutrient availability drives community structure and ecosystem processes, especially in tropical lagoons that are typically oligotrophic but often receive allochthonous inputs from land. Terrestrially derived nutrients are introduced to tropical lagoons by surface runoff and submarine groundwater discharge, which are influenced by seasonal precipitation. However, terrigenous inputs presumably diminish along the onshore–offshor...
Preliminary insights into manta ray (Mobula alfredi and M. birostris) population demographics and distribution in South AfricaNARA Subscribed
Both the reef manta ray, Mobula alfredi and oceanic manta ray M. birostris , are repeatedly observed in South Africa, yet little is known about the distributions of either species. In this study, we collated citizen science observations since 2003 to reveal six areas in the KwaZulu-Natal (KZN) and Eastern Cape provinces, where manta rays have been sighted across multiple years. Using their unique ventral spot patterning, 184 i...
Effects of the Aquatic Herbicide Diquat on Non-Target Aquatic Biota: A Mesocosm StudyNARA Subscribed
Invasive aquatic plants threaten the health of aquatic ecosystems, and demand for chemical control is likely to increase as nuisance levels are reached. Diquat is a contact herbicide registered in many countries to control invasive aquatic plants. The objective of our study was to assess the effects of the aquatic herbicide diquat (Reward®) on North American native and non-native plants, algal communities, an amphipod and an a...
Rationale Both the paraventricular nucleus of the thalamus (PVT) and the neuropeptide, pituitary adenylate cyclase-activating polypeptide (PACAP), are thought to be involved in food intake. Importantly, PACAP is expressed in cells of the PVT. Objectives To determine if PACAP in cells of the PVT might mediate some of the involvement of the PVT with palatable food intake. Methods In male and female C57BL/6 J mice and PACAP-Cre t...
Germline copy number variants and endometrial cancer riskNARA Subscribed
Known risk loci for endometrial cancer explain approximately one third of familial endometrial cancer. However, the association of germline copy number variants (CNVs) with endometrial cancer risk remains relatively unknown. We conducted a genome-wide analysis of rare CNVs overlapping gene regions in 4115 endometrial cancer cases and 17,818 controls to identify functionally relevant variants associated with disease. We identif...
Behavior, site use and demographics of shortfin devil rays, Mobula kuhlii, at a newly-discovered cleaning area in South AfricaNARA Subscribed
Many shark and ray species show affinity to specific sites, making these areas critical for their survival. These include cleaning stations: locations on reefs where cleaner fish remove parasites and clean wounds, which is important for maintaining health. Cleaning stations also function as social gathering sites, or resting points, where courtship and mating can occur. In this study, we identify an aggregation site for the sh...
The surface ocean is the main source of iodine to the atmosphere, where it plays a crucial role including in the catalytic removal of tropospheric ozone. The availability of surface oceanic iodine is governed by its biogeochemical cycling, the controls of which are poorly constrained. Here we show a near two-year time series of the primary iodine species, iodide, iodate and dissolved organic iodine (DOI) in inner shelf marine...
Structure drag from offshore wind turbines and its physical impacts on the marine environment of the German Bight are investigated in this study. The flow past vertical cylinders, such as wind turbine foundations, and associated turbulent mixing has long been studied, but questions remain about anticipated regional implications of offshore wind infrastructure on physical and biogeochemical conditions. Here, we present two exis...
Planktic foraminifera test iodine to calcium ratios represent an emerging proxy method to assess subsurface seawater oxygenation states. Several core-top studies show lower planktic foraminifera I/Ca in locations with oxygen depleted subsurface waters compared to well oxygenated environments. The reasoning behind this trend is that only the oxidized species of iodine, iodate, is incorporated in foraminiferal calcite. The I/Ca...