Blar i Faculty of Mathematics and Natural Sciences på forfatter "Hannisdal, Bjarte"

Viser treff 1-9 av 9

    • Application of Clumped Isotope Thermometry to Benthic Foraminifera 

      Piasecki, Alison; Bernasconi, Stefano M.; Grauel, Anna-Lena; Hannisdal, Bjarte; Ho, Sze Ling; Leutert, Thomas Jan; Marchitto, Thomas M.; Meinicke, Niklas; Tisserand, Amandine Aline; Meckler, Anna Nele (Peer reviewed; Journal article, 2019-04)
      Obtaining absolute temperatures of the ocean in deep time is complicated by the lack of constraints on seawater chemistry. Seawater salinity, carbonate ion concentration, δ18O, and elemental abundance changes may obscure ...

    • Causality from palaeontological time series 

      Hannisdal, Bjarte; Liow, Lee Hsiang (Peer reviewed; Journal article, 2018-07)
      As custodians of deep time, palaeontologists have an obligation to seek the causes and consequences of long‐term evolutionary trajectories and the processes of ecosystem assembly and collapse. Building explicit process ...

    • Disentangling rock record bias and common-cause from redundancy in the British fossil record 

      Dunhill, Alexander M.; Hannisdal, Bjarte; Benton, Michael J. (Peer reviewed; Journal article, 2014-09-04)
      The fossil record documents the history of life, but the reliability of that record has often been questioned. Spatiotemporal variability in sedimentary rock volume, sampling and research effort especially frustrates ...

    • Eurasian Ice Sheet collapse was a major source of Meltwater Pulse 1A 14,600 years ago 

      Brendryen, Jo; Haflidason, Haflidi; Yokoyama, Yusuke; Haaga, Kristian Agasøster; Hannisdal, Bjarte (Journal article; Peer reviewed, 2020)
      Rapid sea-level rise caused by the collapse of large ice sheets is a threat to human societies. In the last deglacial period, the rate of global sea-level rise peaked at more than 4 cm yr−1 during Meltwater Pulse 1A, which ...

    • Evolution of temperature optimum in Thermotogaceae and the prediction of trait values of uncultured organisms 

      Dahle, Håkon; Hannisdal, Bjarte; Steinsbu, Bjørn Olav; Ommedal, Hege; Einen, Jørn; Jensen, Sigmund; Larsen, Øyvind; Øvreås, Lise; Norland, Svein (Peer reviewed; Journal article, 2011-06-03)
      Quantitative characterization of the mode and rate of phenotypic evolution is rarely applied to prokaryotes. Here, we present an analysis of temperature optimum (Topt) evolution in the thermophilic family Thermotogaceae, ...

    • Mapping Microbial Abundance and Prevalence to Changing Oxygen Concentration in Deep-Sea Sediments Using Machine Learning and Differential Abundance 

      Møller, Tor Einar; Moine-Bauer, Sven Le; Hannisdal, Bjarte; Zhao, Rui; Baumberger, Tamara; Roerdink, Desiree Lisette; Dupuis, Amandine; Thorseth, Ingunn Hindenes; Pedersen, Rolf B.; Jørgensen, Steffen Leth (Journal article; Peer reviewed, 2022)
      Oxygen constitutes one of the strongest factors explaining microbial taxonomic variability in deep-sea sediments. However, deep-sea microbiome studies often lack the spatial resolution to study the oxygen gradient and ...

    • Nitrifier abundance and diversity peak at deep redox transition zones 

      Zhao, Rui; Hannisdal, Bjarte; Mogollon, Josè M.; Jørgensen, Steffen Leth (Peer reviewed; Journal article, 2019-06-14)
      More than half of the global ocean floor is draped by nutrient-starved sediments characterized by deep oxygen penetration and a prevalence of oxidized nitrogen. Despite low energy availability, this habitat hosts a vast ...

    • On how the power supply shapes microbial survival 

      Diego Castro, David; Hannisdal, Bjarte; Dahle, Håkon (Journal article; Peer reviewed, 2021)
      Understanding how environmental factors affect microbial survival is an important open problem in microbial ecology. Patterns of microbial community structure have been characterized across a wide range of different ...

    • Transfer entropy computation using the Perron-Frobenius operator 

      Diego, David; Haaga, Kristian Agasøster; Hannisdal, Bjarte (Peer reviewed; Journal article, 2019)
      We propose a method for computing the transfer entropy between time series using Ulam's approximation of the Perron-Frobenius (transfer) operator associated with the map generating the dynamics. Our method differs from ...