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- Creator:
- Mukhopadhyay, Agnit, Daniel T Welling, Michael W Liemohn, Aaron J Ridley, Shibaji Chakrabarty, and Brian J Anderson
- Description:
- An updated auroral conductance module is built for global models, using nonlinear regression & empirical adjustments to span extreme events., Expanded dataset raises the ceiling of conductance values, impacting the ionospheric potential dB/dt & dB predictions during extreme events., and Application of the expanded model with empirical adjustments refines the conductance pattern, and improves dB/dt predictions significantly.
- Keyword:
- Space Weather Forecasting, Extreme Weather, Ionosphere, Magnetosphere, MI Coupling, Ionospheric Conductance, Auroral Conductance, Aurora, SWMF, SWPC, Nonlinear Regression, and dB/dt
- Citation to related publication:
- Mukhopadhyay, A., Welling, D. T., Liemohn, M. W., Ridley, A. J., Chakraborty, S., & Anderson, B. J. (2020). Conductance Model for Extreme Events: Impact of Auroral Conductance on Space Weather Forecasts. Space Weather, 18(11), e2020SW002551. https://doi.org/10.1029/2020SW002551
- Discipline:
- Engineering and Science
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- Creator:
- R. Paul Acosta
- Description:
- In this study, the state-of-the-art isotope-enable global climate model (iCESM1.2) simulations of the middle Miocene and the early Eocene and Cenomanian were used to comprehensively investigate the climate forcing of paleogeography, Andean paleoelevation, global pCO2, and vegetation on the South American continent.
- Keyword:
- South America , Hydroclimate, Water isotope system, and Global climate modeling
- Discipline:
- Science
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- Creator:
- Umaña, María Natalia, Zambrano, Jenny, Weemstra, Monique, and Allen, Dave
- Description:
- The objective of this research was to improve our understanding of tree growth from underlying variation in leaf and root functional traits. This knowledge ultimately enhances our knowledge of the above- and belowground processes that are involved in structuring forest communities. To this end, we determine which, how and to what degree (combinations of) leaf and root traits influence growth rates across ten temperate tree species along a soil carbon (C) and N gradient growing at the Big Woods plot at the E.S. George Reserve, Pickney, MI. This plot is part of the Smithsonian Institution's Forest Global Earth Observatory (ForestGEO) global network of forest research sites. https://forestgeo.si.edu/ and This dataset contains data on the leaf and root traits of several individuals from tree species, as well as on the soil properties at the Big Woods plots at the E.S. George Reserve, Pickney, MI. Data were collected in June 2019, and used to explain and predict the growth rates of the trees at Big Woods. [Growth data were obtained from Allen et al., 2019, https://doi.org/10.7302/wx55-kt18]. Each file contains data on leaf traits, root traits, and soil properties. Trait data are presented per individual tree for each of the 10 study species. Soil data are represented per soil sample, with four soil samples collected per subplot throughout the Big Woods plot (see legend, and publication for explanation). Descriptions and units per variable/column are provided in the legend tab in each file.
- Keyword:
- ecology, forests, Michigan, ForestGEO, Big Woods, Roots, Leaves, Tree growth, and Forest soils
- Citation to related publication:
- M. Weemstra, J. Zambrano, D. Allen, MN Umaña. (In press) Tree growth increases through opposing above- and belowground resource strategies. Journal of Ecology. https://doi.org/10.1111/1365-2745.13729
- Discipline:
- Science
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- Creator:
- Nunley, Hayden, Nagashima, Mikiko, Martin, Kamirah, Lorenzo Gonzalez, Alcides, Suzuki, Sachihiro C., Norton, Declan A., Wong, Rachel O. L., Raymond, Pamela A., and Lubensky, David K.
- Description:
- This dataset contains images of UV cone nuclei near the retinal margin in live fish. These UV cones express a transgenic fluorescent reporter (that is nuclear-localized and photoconvertible). The most important images in this dataset are: Zoomed-out (1X magnification) images immediately after photoconversion Zoomed-out (1X magnification) images two to four days after photoconversion In the images immediately after photoconversion, we check if the row orientation rotates by more than a certain amount (10 degrees, 12 degrees, 14 degrees, etc.) at the retinal margin. If so, we call the region coinciding with this domain rotation an existing grain boundary. We, then, check where new Y-junctions are incorporated (by the time of later imaging) to see if they are preferentially incorporated near existing grain boundaries.
- Keyword:
- zebrafish cone mosaic, topological defects, tissue patterning, grain boundaries, and photoconversion
- Citation to related publication:
- Nunley, H., Nagashima, M., Martin, K., Gonzalez, A. L., Suzuki, S. C., Norton, D. A., Wong, R. O. L., Raymond, P. A., & Lubensky, D. K. (2020). Defect patterns on the curved surface of fish retinae suggest a mechanism of cone mosaic formation. PLOS Computational Biology, 16(12), e1008437. https://doi.org/10.1371/journal.pcbi.1008437 and Hayden Nunley, Mikiko Nagashima, Kamirah Martin, Alcides Lorenzo Gonzalez, Sachihiro C. Suzuki, Declan Norton, Rachel O. L. Wong, Pamela A. Raymond, David K. Lubensky. Defect patterns on the curved surface of fish retinae suggest mechanism of cone mosaic formation. bioRxiv 806679; doi: https://doi.org/10.1101/806679
- Discipline:
- Science
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- Creator:
- Zhou, Hongyang
- Description:
- The largest moon in the solar system, Ganymede, is the only moon known to possess a strong intrinsic magnetic field and a corresponding magnetosphere. Using the latest version of Space Weather Modeling Framework (SWMF), we study the upstream plasma interactions and dynamics in this sub-Alfvenic system. Results from the Hall MHD and the coupled MHD with embedded Particle-in-Cell (MHD-EPIC) models are compared. We find that under steady upstream conditions, magnetopause reconnection occurs in a non-steady manner. Flux ropes of Ganymede's radius in length form on the magnetopause at a rate about 2/minute and create spatiotemporal variations in plasma and field properties. Upon reaching proper grid resolutions, the MHD-EPIC model can resolve both electron and ion kinetics at the magnetopause and show localized non-gyrotropic behavior inside the diffusion region. The estimated global reconnection rate from the models is about 80 kV with 60% efficiency, and there is weak evidence of about 1 minute periodicity in the temporal variations due to the dynamic reconnection process.
- Keyword:
- MHD, PIC, Ganymede, and magnetosphere
- Citation to related publication:
- Zhou, H., Tóth, G., Jia, X., & Chen, Y. (2020). Reconnection-Driven Dynamics at Ganymede’s Upstream Magnetosphere: 3-D Global Hall MHD and MHD-EPIC Simulations. Journal of Geophysical Research: Space Physics, 125(8), e2020JA028162. https://doi.org/10.1029/2020JA028162
- Discipline:
- Science
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- Creator:
- Lamb, Abigail M.
- Description:
- This Work contains Supplemental File S3-1, Supplemental File S3-2, Supplemental Table S4-1, Supplemental Table S4-2, and Supplemental Table S4-3 from the dissertation entitled "Genetic Determinants of the Development and Evolution of Drosophila Pigmentation" by Abigail M. Lamb. Supplemental File S3-1 is entitled "Raw data measuring CHC abundance" and contains the measurements of cuticular hydrocarbons used for analysis in Chapter 3 of the dissertation. These data are meant to be read into the R code contained in Supplemental File S3-2, "R code used for analyzing CHC data" to reproduce the results reported in Chapter 3 of the dissertation. Supplemental Tables S4-1, S4-2, and S4-3 contain original phenotyping data, notes, and summary data from the miRNA overexpression and competitive inhibition experiments described in Chapter 4 of the dissertation.
- Citation to related publication:
- Lamb, A. M., Wang, Z., Simmer, P., Chung, H., & Wittkopp, P. J. (2020). Ebony Affects Pigmentation Divergence and Cuticular Hydrocarbons in Drosophila americana and D. novamexicana. Frontiers in Ecology and Evolution, 8. https://doi.org/10.3389/fevo.2020.00184
- Discipline:
- Science
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- Creator:
- BIRDS Lab, U. Michigan
- Description:
- These data were produced in an attempt to characterize the turning and steering behaviors of 1-DoF multi-legged (hexpedal in this case) robots. Such turning behaviors require sliding contact points. All the data is provided in a single, large .csv.gz file (416256 rows); additional details and example code in the README
- Keyword:
- robot, multilegged, and steering
- Citation to related publication:
- BIRDS Lab, U. BigAnt v6 robot motion tracking data - RAW dataset [Data set], University of Michigan - Deep Blue Data. https://doi.org/10.7302/024q-kk06, Revzen, S., & Guckenheimer, J. (2008). Estimating the phase of synchronized oscillators. Phys. Rev. E, 78, 051907. http://dx.doi.org/10.1103/PhysRevE.78.051907, and Dan Zhao and Shai Revzen 2020 Bioinspir. Biomim. 15 045001 https://doi.org/10.1088/1748-3190/ab84c0
- Discipline:
- Engineering
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- Creator:
- Hinz, Isaac and Johnson, Jena
- Description:
- Laboratory experiments were conducted to compare iron precipitation under completely ferruginous conditions with solutions that contain a low amount of oxidized iron, which can be seen as a proxy for iron oxidation in the environment. and Some XRD files are from a copper source (Cu_XRD) and others are from a cobalt source (Co_XRD).
- Keyword:
- Iron silicates, Greenalite, and Archean
- Citation to related publication:
- Isaac L. Hinz, Christine Nims, Samantha Theuer, Alexis S. Templeton, Jena E. Johnson; Ferric iron triggers greenalite formation in simulated Archean seawater. Geology 2021; doi: https://doi.org/10.1130/G48495.1
- Discipline:
- Science
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- Creator:
- Nikolov, Denislav P, Srivastava, Siddhartha, Abeid, Bachir A, Scheven, Ulrich M, Arruda, Ellen M, Garikipati, Krishna, and Estrada, Jonathan B
- Description:
- Contemporary material characterisation techniques that leverage deformation fields and the weak form of the equilibrium equations face challenges in the numerical solution procedure of the inverse characterisation problem. As material models and descriptions differ, so too must the approaches for identifying parameters and their corresponding mechanisms. The widely-used Ogden material model can be comprised of a chosen number of terms of the same mathematical form, which presents challenges of parsimonious representation, interpretability, and stability. Robust techniques for system identification of any material model are important to assess and improve experimental design, in addition to their centrality to forward computations. Using fully 3D displacement fields acquired in silicone elastomers with our recently-developed magnetic resonance cartography (MR-u) technique on the order of ~20,000 points per sample, we leverage PDE-constrained optimisation as the basis of variational system identification of our material parameters. We incorporate the statistical F-test to maintain parsimony of representation. Using a new, local deformation decomposition locally into mixtures of biaxial and uniaxial tensile states, we evaluate experiments based on an analytical sensitivity metric, and discuss the implications for experimental design. This repository contains the acquired data and MRI processing code used in this work.
- Keyword:
- continuum mechanics, magnetic resonance, sensitivity, full-field deformations, physics inference, mechanics, mechanical engineering, and computational mechanics
- Citation to related publication:
- https://doi.org/10.48550/arXiv.2204.03122
- Discipline:
- Engineering
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- Creator:
- Crisp, Dakota N., Parent, Rachel, Nakatani, Mitsuyoshi, Murphy, Geoffrey G. , and Stacey, William C.
- Description:
- This data and scripts are meant to test and show that seizure onset dynamics can be modulated using anti-epileptic drugs. A zip file is included that contains all waveform data, MATLAB processing scripts, and metadata. The MATLAB scripts allow for visual review validation and objective feature analysis. The file includes various README files explaining the scripts and their relationships in greater detail.
- Keyword:
- Bifurcation, Epilepsy, Seizure, and Electrophysiology
- Discipline:
- Health Sciences, Engineering, and Science