M. Needham results 36
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Dynamics and Eco‐Genomics of Baltic Sea Nitrifiers: Seasonality, Niches, Interactions and Genomic UniquenessNARA Subscribed
Nitrification is widespread across marine systems, yet the ecological and evolutionary drivers shaping nitrifier populations remain largely unknown. The Baltic Sea, a brackish basin with pronounced gradients in salinity, oxygen, nutrients and strong seasonality, is a valuable model environment to investigate these questions. Here, we combined metagenomics and rRNA gene sequencing to characterise the spatiotemporal dynamics and...
Fan shells (Family Pinnidae) have high ecological importance but are facing global declines including in New Zealand. Given the scarcity of data regarding the degree of these losses, understanding current population spatial extents and distributional drivers is needed for restoration management. A subtidal towed underwater camera survey was conducted at 62 sites to elucidate Atrina zelandica extent in Tauranga Harbour, Bay of...
Extreme physical-oceanographic events, such as marine heatwaves, fluvial floods, droughts and storm surges, have major impacts on local communities, economic sectors and ecosystems, and their frequency, intensity and duration increase due to climate change. There is a lack of understanding of the systemic drivers of extreme events as well as of their interconnected impacts on estuarine and coastal ecosystems. This knowledge is...
Differentiation grade is highly concordant between matched primary and metastatic colorectal cancerNARA Subscribed
Differentiation grade of colorectal cancers (CRC) is histologically defined by the proportion of the tumour which retains the glandular architecture of the normal colon. Poorly differentiated CRCs display loss of glandular architecture and canonical markers of colonic differentiation and are associated with increased metastatic capacity and poorer prognosis. It is currently unclear whether poorly differentiated cells within a...
Role of hepatocellular senescence in the development of hepatocellular carcinoma and the potential for therapeutic manipulationNARA Subscribed
Accumulation of senescent hepatocytes is universal in chronic liver disease (CLD). This study investigates an association between hepatocyte senescence and hepatocellular carcinoma (HCC) and explores the therapeutic role of sirolimus. Background liver biopsies from 15 patients with cirrhosis and HCC and 45 patients with cirrhosis were stained for p16, a marker of cell senescence. STAM™ mice were randomized into 3 groups of 5 a...
The Effect of Sediment Mud Content on Primary Production in Seagrass and Unvegetated Intertidal FlatsNARA Subscribed
As a consequence of anthropogenic activities and climate change, accelerated terrestrial sediment runoff is causing the gradual mudification of soft sediment estuarine habitats worldwide. Increased sediment mud content (< 63 µm) has been recognised to alter seagrass morphology and cause declines in primary production in unvegetated habitats. However, the effect of increased mud content on primary production in seagrass meadows...
Going under: The implications of sea‐level rise and reduced light availability on intertidal primary productionNARA Subscribed
Estuarine intertidal flats are known for high rates of primary production, however, globally these ecosystems are under threat from rising sea‐level and accelerated inputs of terrestrial sediments. These stressors simultaneously alter the duration of submersion/emersion periods and water‐column turbidity impacting seafloor photoperiods. To assess how changes in submergence time and water‐clarity can affect benthic primary prod...
Demographic composition, not demographic diversity, predicts biomass and turnover across temperate and tropical forestsNARA Subscribed
The growth and survival of individual trees determine the physical structure of a forest with important consequences for forest function. However, given the diversity of tree species and forest biomes, quantifying the multitude of demographic strategies within and across forests and the way that they translate into forest structure and function remains a significant challenge. Here, we quantify the demographic rates of 1961 tr...
Summary Universal primers for SSU rRNA genes allow profiling of natural communities by simultaneously amplifying templates from Bacteria, Archaea, and Eukaryota in a single PCR reaction. Despite the potential to show relative abundance for all rRNA genes, universal primers are rarely used, due to various concerns including amplicon length variation and its effect on bioinformatic pipelines. We thus developed 16S and 18S rRNA m...
Summary Marine Thaumarchaeota are abundant ammonia‐oxidizers but have few representative laboratory‐cultured strains. We report the cultivation of Candidatus Nitrosomarinus catalina SPOT01, a novel strain that is less warm‐temperature tolerant than other cultivated Thaumarchaeota. Using metagenomic recruitment, strain SPOT01 comprises a major portion of Thaumarchaeota (4–54%) in temperate Pacific waters. Its complete 1.36 Mbp...
Summary Microbial community analysis via high‐throughput sequencing of amplified 16S rRNA genes is an essential microbiology tool. We found the popular primer pair 515F ( 515F‐C ) and 806R greatly underestimated (e.g. SAR 11) or overestimated (e.g. Gammaproteobacteria) common marine taxa. We evaluated marine samples and mock communities (containing 11 or 27 marine 16S clones), showing alternative primers 515F‐ Y (5′‐ GTG Y CAG...