Article
Geochemistry & Geophysics
Yang Lu, Dunfan Wang, Xiaodong Jiang, Zhiyong Lin, Yiping Yang, Qingsong Liu
Summary: Magnetotactic bacteria leave fossil bacterial magnetite in sediments, reflecting changes in redox conditions. The Eocene-Oligocene transition marks a shift in Cenozoic climate evolution from greenhouse to icehouse, impacting the abundance and morphology of magnetofossils in the eastern equatorial Pacific Ocean. The synchronous variation of magnetofossils with paleoenvironmental changes suggests their potential as an effective proxy for paleoenvironmental studies.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Multidisciplinary Sciences
Alberto Perez-Huerta, Chiara Cappelli, Ylenia Jabalera, Tanya Prozorov, Concepcion Jimenez-Lopez, Dennis A. Bazylinski
Summary: Biominerals play an important role in the geological record as archives of life and environmental processes. However, identifying the biogenic nature of minerals with nanometer-sized dimensions has been challenging. This study shows that nanometer-sized magnetite crystals, resembling those produced by magnetotactic bacteria, can be identified as biogenic by the presence of a coupled C-N signal. This finding is significant for understanding the earliest presence of life on Earth and potentially on other planets.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Multidisciplinary Sciences
Dalin Zhang, Yunjuan Peng, Yi Xu, Chenyue Du, Yumei Zhang, Nan Wang, Yunhao Chong, Hongwei Wang, Daohua Wu, Jintao Liu, Hailong Zhang, Lingyun Lu, Jiqiang Liu
Summary: High-speed train operation data is a valuable resource for data-driven research. However, the currently available datasets are not comprehensive enough. This dataset contains train operation data from a high-speed railway network and can be used for research on complex dynamic systems and intelligent transportation, as well as for solving railway operation and management problems.
Article
Environmental Sciences
Daniel Woods, Michael J. Cheadle, Barbara E. John, Christopher R. German, Cindy L. Van Dover
Summary: When hydrothermal activity stops at black-smoker chimneys on mid-ocean ridges, invertebrates hosting chemoautotrophic endosymbionts decline and disappear, but the chimneys remain as relicts. This study found that suspension-feeding brisingid seastars are non-randomly distributed on relict chimneys near active black smokers on Pito Seamount. The presence of relict sulfide structures and proximity to black smokers play key roles in maintaining dense populations of brisingid seastars in similar environments.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Geochemistry & Geophysics
Matthieu Amor, Juan Wan, Ramon Egli, Julie Carlut, Christophe Gatel, Ingrid Marie Andersen, Etienne Snoeck, Arash Komeili
Summary: Magnetotactic bacteria produce magnetic nanoparticles that contribute to the magnetization of sediments and rocks. This study shows that the observed magnetofossil fingerprints are produced by a combination of single-stranded and multi-stranded chains, and that the anisotropy of the chains is the key factor for distinguishing magnetofossils from other natural magnetite particles. The characteristics of the magnetofossils depend on the proportion of magnetosomes and the relative abundances of single-stranded and multi-stranded chains. This research has important implications for paleoclimatology, paleontology, and phylogenetics, and provides reference data for distinguishing different MTB lineages and sources of magnetite particles.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Multidisciplinary Sciences
Aixia Guo, Sakima Smith, Yosef M. Khan, James R. Langabeer, Randi E. Foraker
Summary: The study used a deep learning technique-long short-term memory (LSTM) model to predict cardiac dysrhythmias and demonstrated that LSTM model outperformed traditional machine learning models, with blood pressure being the most influential feature. These findings may be used to prevent cardiac dysrhythmias in the outpatient setting.
Article
Chemistry, Analytical
Ada Kanapskyte, Elizabeth M. Hawkins, Lauren C. Liddell, Shilpa R. Bhardwaj, Diana Gentry, Sergio R. Santa Maria
Summary: In light of future missions beyond LEO and the potential establishment of bases on the Moon and Mars, research on the effects of the deep space environment on biology is essential. The upcoming deep space biological missions will focus on microbial organisms and plant seeds using miniaturized technologies, with CubeSats playing a key role in exploring relevant space environments.
Article
Geochemistry & Geophysics
Robin Havas, Jairo F. Savian, Vincent Busigny
Summary: This study investigates the potential of Fe isotopes as a biosignature in magnetofossils in a sedimentary sequence from the Indian Ocean recording the Middle Eocene Climatic Optimum. The Fe isotope compositions of oxides outside the magnetofossil-rich interval are interpreted as reflecting dominantly hydrothermal contribution. The study provides important constraints on paleoclimate and magnetofossil biogenicity evaluation.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Multidisciplinary Sciences
Xuchen Wang, Mohammad Sajjad Mirmoosa, Viktar S. Asadchy, Carsten Rockstuhl, Shanhui Fan, Sergei A. Tretyakov
Summary: Photonic time crystals are artificial materials with spatially uniform but temporally varying electromagnetic properties. This study extends the concept of photonic time crystals to two-dimensional artificial structures called metasurfaces. By designing a microwave metasurface, the researchers confirmed the existence of momentum bandgaps and exponential wave amplification, demonstrating the potential of metasurfaces as a material platform for emerging photonic space-time crystals and for amplifying surface-wave signals in wireless communications.
Article
Astronomy & Astrophysics
Massimo Tinto, Sanjeev Dhurandhar, Prasanna Joshi
Summary: Time-delay interferometry (TDI) is a data processing technique that cancels laser phase fluctuations to study gravitational wave signals at a requisite precision. The matrix formulation in TDI effectively handles laser noises and Doppler measurements, providing potential advantages for future gravitational wave projects. The cancellation of laser noises at arbitrary time points by linearly combining a finite number of Doppler data samples is a key feature of TDI's matrix representation.
Article
Geochemistry & Geophysics
Pengfei Xue, Liao Chang, Zhaowen Pei, Richard J. Harrison
Summary: The origin of giant magnetofossils has remained a mystery due to the absence of modern analogues. This study discovered abundant giant magnetofossils in North Atlantic marine sediments, not only during the Palaeocene-Eocene Thermal Maximum but also before and after this period. The findings suggest that giant biogenic magnetite crystals were not exclusively produced during ancient hyperthermal events.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Physics, Multidisciplinary
Hady Moussa, Gengyu Xu, Shixiong Yin, Emanuele Galiffi, Younes Ra'di, Andrea Alu
Summary: Time reflection is the inversion of temporal evolution of a signal that occurs when there is a uniform change in the properties of the host material. This phenomenon is similar to spatial interfaces and can be exploited for extreme wave manipulation. In this study, photonic time reflection and broadband frequency translation were observed in a switched transmission-line metamaterial, demonstrating the temporal counterpart of a Fabry-Perot cavity. This paves the way for the realization of time metamaterials and Floquet photonic crystals for advanced photon manipulation in space and time.
Article
Geology
Yi Qin, Xiaomin Zhu, Shifa Zhu, Brandon McElroy
Summary: The study revealed the significant impact of paleoclimate on the morphology and depositional processes of shoal-water deltaic systems, distinguishing between early humid and later arid climatic stages to define deltaic sedimentary sequences and propose conceptual depositional models analogous to modern lake and river deltas.
Article
Physics, Multidisciplinary
Romain Tirole, Stefano Vezzoli, Emanuele Galiffi, Iain Robertson, Dries Maurice, Benjamin Tilmann, Stefan A. Maier, John B. Pendry, Riccardo Sapienza
Summary: A temporal version of Young's double-slit experiment shows interference in the frequency domain when light interacts with time slits produced by ultrafast changes in the refractive index.
Article
Geography, Physical
Norbert Marwan, Jonathan F. Donges, Reik Donner, Deniz Eroglu
Summary: This study discusses the importance of identifying and characterising dynamical regime shifts in palaeoclimate time series, introduces several methods based on concepts from nonlinear dynamics, complex systems science, information theory, and stochastic analysis, and applies these methods to analyze marine palaeoclimate proxy records of African climate variations. The results indicate complementarity among these methods in providing information about different aspects of dynamical regime shifts in palaeoclimate, and detect significant correlations of these shifts with variations of Earth's orbit.
QUATERNARY SCIENCE REVIEWS
(2021)