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- Creator:
- Kort, Eric A. and Smith, Mackenzie L.
- Description:
- Data collected by Mooney aircraft over Houston and Denver in Summer 2020. Flights typically were designed to measure within the boundary layer in a raster pattern perpendicular to wind direction, thus sampling the urban plume repeatedly. Vertical profiles are conducted on each flight to capture the vertical structure and mixing depths of the atmosphere. The data file contains all merged flight data from each flight day.
- Keyword:
- Atmospheric Chemistry, Air Quality, Houston, Denver, and Covid-19
- Discipline:
- Science
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- Creator:
- Moore, Talia Y, Villacis Nunez, C Nathaly, Ray, Andrew P, and Cooper, Kimberly L
- Description:
- Hind limbs can undergo dramatic changes in loading conditions during the transition from quadrupedal to bipedal locomotion. For example, the most early diverging bipedal jerboas (Rodentia: Dipodidae) are some of the smallest mammals in the world, with body masses that range 2-4 grams. The larger jerboa species exhibit developmental and evolutionary fusion of the central three metatarsals into a single cannon bone. We hypothesize that body size reduction and metatarsal fusion are mechanisms to maintain the safety factor of the hind limb bones despite the higher ground reaction forces associated with bipedal locomotion. Using finite element analysis to model collisions between the substrate and the metatarsals, we found that body size reduction was insufficient to reduce bone stress on unfused metatarsals, based on the scaled dynamics of larger jerboas, and that fused bones developed lower stresses than unfused bones when all metatarsals are scaled to the same size and loading conditions. Based on these results, we conclude that fusion reinforces larger jerboa metatarsals against high ground reaction forces. Because smaller jerboas with unfused metatarsals develop higher peak stresses in response to loading conditions scaled from larger jerboas, we hypothesize that smaller jerboas use alternative dynamics of bipedal locomotion that reduces the impact of collisions between the foot and substrate.
- Keyword:
- finite element, functional morphology, bipedal, jerboa, metatarsus, and bone fusion
- Citation to related publication:
- Villacis Nunez, Ray, Cooper, Moore (submitted). Body size reduction and metatarsal fusion were distinct mechanisms to resist bending as jerboas (Dipodidae) transitioned from quadrupedal to bipedal.
- Discipline:
- Science and Engineering
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- Creator:
- Malhotra, Garima and Ridley, Aaron J.
- Description:
- The goal of this research study is to understand the sensitivity of the IT region to the spatial variation of Kzz. This is done using the IT model, GITM, with different settings and spatial distributions for Kzz. We introduce latitudinal bands (longitudinally uniform) of 30 degrees width at equatorial and polar latitudes during different seasons similar to the previous observations in literature. We investigate the mechanisms through which a non-uniform global distribution of Kzz can alter the dynamics and thermal structure of the thermosphere, and how these effects compare to when a globally uniform value of Kzz is used.
- Keyword:
- Mesosphere and Lower Thermosphere, Eddy Diffusion, Thermospheric Dynamics, Thermospheric composition and mixing, Lower-Upper Thermosphere Vertical Coupling, Global Ionosphere Thermosphere Model, and Eddy Mixing
- Citation to related publication:
- Malhotra, G., Ridley, A.J. (2021). Impacts of Spatially Varying Eddy Diffusion in the Lower Thermosphere on the Ionosphere and Thermosphere using GITM - Sensitivity Study. and A.J. Ridley, Y. Deng, G. Tóth, The global ionosphere–thermosphere model, Journal of Atmospheric and Solar-Terrestrial Physics, Volume 68, Issue 8, 2006, Pages 839-864, ISSN 1364-6826, https://doi.org/10.1016/j.jastp.2006.01.008.
- Discipline:
- Science
-
- Creator:
- Shi, Yining
- Description:
- Statistical study of Swarm observations and two Earth magnetic field models: IGRF-12 and CHAOS-6 categorized by Kp*10 index. Data analysis done on https://viresclient.readthedocs.io/en/latest/ JupyterLab.
- Discipline:
- Engineering
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- Creator:
- Brenner, Austin, M
- Description:
- Coupling between the solar wind and magnetosphere can be expressed in terms of energy transfer through the separating boundary known as the magnetopause. Geospace simulation is performed using the Space Weather Modeling Framework (SWMF) of a multi-ICME impact event on February 18-20, 2014 in order to study the energy transfer through the magnetopause during storm conditions. The magnetopause boundary is identified using a modified plasma $\beta$ and fully closed field line criteria to a downstream distance of $-20R_{e}$. Observations from Geotail, Themis, and Cluster are used as well as the Shue 1998 model to verify the simulation field data results and magnetopause boundary location. Once the boundary is identified, energy transfer is calculated in terms of total energy flux \textbf{K}, Poynting flux \textbf{S}, and hydrodynamic flux \textbf{H}. Surface motion effects are considered and the regional distribution of energy transfer on the magnetopause surface is explored in terms of dayside $\left(X>0\right)$, flank $\left(X<0\right)$, and tail cross section $\left(X=X_{min}\right)$ regions. It is found that total integrated energy flux over the boundary is nearly balanced between injection and escape, and flank contributions dominate the Poynting flux injection. Poynting flux dominates net energy input, while hydrodynamic flux dominates energy output. Surface fluctuations contribute significantly to net energy transfer and comparison with the Shue model reveals varying levels of cylindrical asymmetry in the magnetopause flank throughout the event. Finally existing energy coupling proxies such as the Akasofu $\epsilon$ parameter and Newell coupling function are compared with the energy transfer results.
- Keyword:
- Space plasma, Magnetosphere, MHD simulations, Magnetopause, Substorm, Energy transfer, and Poynting flux
- Citation to related publication:
- Brenner A, Pulkkinen TI, Al Shidi Q and Toth G (2021) Stormtime Energetics: Energy Transport Across the Magnetopause in a Global MHD Simulation. Front. Astron. Space Sci. 8:756732. doi: 10.3389/fspas.2021.756732
- Discipline:
- Science
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- Creator:
- BIRDS Lab U. Michigan
- Description:
- These data were produced for ARO W911NF-14-1-0573 "Morphologically Modulated Dynamics" and ARO MURI W911NF-17-1-0306 "From Data-Driven Operator Theoretic Schemes to Prediction, Inference, and Control of Systems" to explore the trade-offs between various oscillator coupling models in modeling multilegged locomotion. The data were also used extensively in examining multi-contact slipping, in the studying the influence of number of legs on otherwise identical locomotion patterns, and in the use of geometric mechanics models for multilegged locomotion. Folder and file names encode the meta-data, with names following an informative naming convention documented in the README.
- Keyword:
- phase, multilegged, robot, and locomotion
- Citation to related publication:
- Zhao, D. & Revzen, S. Multi-legged steering and slipping with low DoF hexapod robots Bioinspiration & biomimetics, 2020, 15, 045001 https://doi.org/10.1088/1748-3190/ab84c0 and Zhao, D. Ph.D. Thesis "Locomotion of low-DOF multi-legged robots" University of Michigan 2021 https://deepblue.lib.umich.edu/handle/2027.42/169985
- Discipline:
- Science and Engineering
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- Creator:
- Curlis, JD, Renney, TJ, Davis Rabosky, AR, and Moore, TY
- Description:
- Efficient comparisons of biological color patterns are critical for understanding the mechanisms by which organisms evolve in ecosystems, including sexual selection, predator-prey interactions, and thermoregulation. However, elongate or spiral-shaped organisms do not conform to the standard orientation and photographic techniques required for automated analysis. Currently, large-scale color analysis of elongate animals requires time-consuming manual landmarking, which reduces their representation in coloration research despite their ecological importance. We present Batch-Mask: an automated and customizable workflow to facilitate the analysis of large photographic data sets of non-standard biological subjects. First, we present a user guide to run an open-source region-based convolutional neural network with fine-tuned weights for identifying and isolating a biological subject from a background (masking). Then, we demonstrate how to combine masking with existing manual visual analysis tools into a single streamlined, automated workflow for comparing color patterns across images. Batch-Mask was 60x faster than manual landmarking, produced masks that correctly identified 96% of all snake pixels, and produced pattern energy results that were not significantly different from the manually landmarked data set. The fine-tuned weights for the masking neural network, user guide, and automated workflow substantially decrease the amount of time and attention required to quantitatively analyze non-standard biological subjects. By using these tools, biologists will be able to compare color, pattern, and shape differences in large data sets that include significant morphological variation in elongate body forms. This advance will be especially valuable for comparative analyses of natural history collections, and through automation can greatly expand the scale of space, time, or taxonomic breadth across which color variation can be quantitatively examined.
- Keyword:
- convolutional neural network, photography, sensory ecology, color evolution, vision, and image segmentation
- Citation to related publication:
- Curlis, Renney, Davis Rabosky, Moore (submitted) Batch-Mask: An automated Mask R-CNN workflow to isolate non-standard biological specimens for color pattern analysis.
- Discipline:
- Engineering and Science
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- Creator:
- BIRDS Lab, U. Michigan
- Description:
- These data were produced for ARO W911NF-14-1-0573 "Morphologically Modulated Dynamics" and ARO MURI W911NF-17-1-0306 "From Data-Driven Operator Theoretic Schemes to Prediction, Inference, and Control of Systems" to explore the trade-offs between various oscillator coupling models in modeling multilegged locomotion of Multipod robots with 6,8,10 and 12 legs. The data is stored in .csv.gz files, one file for each robot morphology. Details of how to run the processing code on the raw dataset to generate the processed files found here, as well as example code for loading the data found here, are in the README. This dataset is self contained and can be used on its own without running any of the provided code.
- Citation to related publication:
- Zhao, D. & Revzen, S. Multi-legged steering and slipping with low DoF hexapod robots Bioinspiration & biomimetics, 2020, 15, 045001 https://doi.org/10.1088/1748-3190/ab84c0, Zhao, D. Ph.D. Thesis "Locomotion of low-DOF multi-legged robots" University of Michigan 2021 https://deepblue.lib.umich.edu/handle/2027.42/169985, and BIRDS Lab Multipod robot motion tracking data - RAW data, doi:10.7302/m05a-0d90
- Discipline:
- Engineering and Science
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- Creator:
- Valeriy Tenishev
- Description:
- Here we present an investigation of the variability of Venus' extended oxygen corona. For that, we employ a combination of a fluid model VTGCM for simulating Venus' ionosphere and thermosphere and kinetic model AMPS. We have found excellent agreement of the model results with PVO observations of the corona when the modeling is done assuming the solar maximum conditions, which corresponds to the solar conditions during the observations. We also found that the oxygen density strongly depends on the solar conditions and varies by order of magnitude over a solar cycle. That explains why the extended oxygen corona was observed only at the solar maximum. The result presented in this paper will be used in a later study of the planet's interaction with the ambient solar wind, where the corona model defines the mass loading coefficient.
- Keyword:
- Venus, VTGCM, AMPS, and Venus extended corona
- Discipline:
- Science
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- Creator:
- BIRDS Lab U. Michigan
- Description:
- This dataset contains the videos used for https://doi.org/10.7302/m05a-0d90 (the "raw" motion tracking dataset), and is intended to be unpacked into the same directory tree. The data were produced for ARO W911NF-14-1-0573 "Morphologically Modulated Dynamics" and ARO MURI W911NF-17-1-0306 "From Data-Driven Operator Theoretic Schemes to Prediction, Inference, and Control of Systems" to explore the trade-offs between various oscillator coupling models in modeling multilegged locomotion. The data were also used extensively in examining multi-contact slipping, in the studying the influence of number of legs on otherwise identical locomotion patterns, and in the use of geometric mechanics models for multilegged locomotion. Folder and file names encode the meta-data, with names following an informative naming convention documented in the README.
- Keyword:
- phase, multilegged, robot, and locomotion
- Citation to related publication:
- BIRDS Lab U. Michigan. BIRDS Lab Multipod robot motion tracking data - RAW dataset [Data set], University of Michigan - Deep Blue Data. https://doi.org/10.7302/m05a-0d90, Zhao, D. Ph.D. Thesis "Locomotion of low-DOF multi-legged robots" University of Michigan 2021 https://deepblue.lib.umich.edu/handle/2027.42/169985, and Zhao, D. & Revzen, S. Multi-legged steering and slipping with low DoF hexapod robots Bioinspiration & biomimetics, 2020, 15, 045001 https://doi.org/10.1088/1748-3190/ab84c0
- Discipline:
- Science and Engineering
-
- Creator:
- Ding, J, Moore, TY, and Gan, Z
- Description:
- Jerboas (Jaculus jaculus) are bipedal hopping rodents that frequently transition between gaits (running, hopping, and skipping) throughout their entire speed range. It has been hypothesized that these non-cursorial bipedal gait transitions are likely to enhance their maneuverability and predator evasion ability. However, it is difficult to use the underlying dynamics of these locomotion patterns to predict gait transitions due to the large number of degrees of freedom expressed by the animals. To this end, we used empirical jerboa kinematics and dynamics to develop a unified Spring Loaded Inverted Pendulum model with defined passive swing leg motions. The simulated trajectories from the model precisely matched the experimental data. Jerboas were observed to apply different neutral swing leg angles during locomotion. By investigating the gait structure of the model with coupled and uncoupled neutral swing leg, we found two set of mechanism may explain the frequent gait transitions of jerboas.
- Keyword:
- jerboa, legged locomotion, gait transition, Legged Robots, Dynamics, Bipedal locomotion, and Non-cursorial locomotion
- Citation to related publication:
- Ding, Moore, Gan (submitted) A template model explains jerboa gait transitions across a broad range of speeds. Frontiers in Bioengineering And Biotechnology
- Discipline:
- Science and Engineering
-
- Creator:
- Xiantong Wang
- Description:
- We perform a geomagnetic event simulation using a newly developed magnetohydrodynamic with adaptively embedded particle-in-cell (MHD-AEPIC) model. We have developed effective criteria to identify reconnection sites in the magnetotail and cover them with the PIC model. The MHD-AEPIC simulation results are compared with Hall MHD and ideal MHD simulations to study the impacts of kinetic reconnection at multiple physical scales. At the global scale, the three models produce very similar SYM-H and SuperMag Electrojet (SME) indexes, which indicates that the global magnetic field configurations from the three models are very close to each other. At the mesoscale we compare the simulations with in situ Geotail observations in the tail. All three models produce reasonable agreement with the Geotail observations. The MHD-AEPIC and Hall MHD models produce tailward and earthward propagating fluxropes, while the ideal MHD simulation does not generate flux ropes in the near-earth current sheet. At the kinetic scales, the MHD-AEPIC simulation can produce a crescent shape distribution of the electron velocity space at the electron diffusion region which agrees very well with MMS observations near a tail reconnection site. These electron scale kinetic features are not available in either the Hall MHD or ideal MHD models. Overall, the MHD-AEPIC model compares well with observations at all scales, it works robustly, and the computational cost is acceptable due to the adaptive adjustment of the PIC domain.
- Keyword:
- MHD, PIC, and Magnetosphere
- Discipline:
- Science
-
- Creator:
- Bhaumik, Deesha
- Description:
- This cross-sectional analysis included 584 participants in the Center for Oral Health Research in Appalachia cohort 1 (COHRA1). We sequenced the V4 region of the 16S rRNA of supragingival plaque from 185 caries-active and 565 caries-free teeth using the Illumina MiSeq platform. Sequences were filtered using the R DADA2 package and assigned taxonomy using the Human Oral Microbiome Database ( http://www.homd.org/).
- Keyword:
- Amplicon Sequence Variant
- Citation to related publication:
- In press
- Discipline:
- Health Sciences
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- Creator:
- Sun, Hu, Ren, Jiaen, Chen, Yang, and Zou, Shasha
- Description:
- Our research focuses on providing a fully-imputed map of the worldwide total electron content with high resolution and spatial-temporal smoothness. We fill in the missing values of the original Madrigal TEC maps via estimating the latent feature of each latitude and local time along the 2-D grid and give initial guess of the missing regions based on pre-computed spherical harmonics map. The resulting TEC map has high imputation accuracy and the ease of reproducing. and All data are in HDF5 format and are easy to read using the h5py package in Python. The TEC map is grouped in folders based on years and each file contains a single-day data of 5-min cadence. Each individual TEC map is of size 181*361.
- Keyword:
- Total Electron Content, Matrix Completion, VISTA, Spherical Harmonics, and Spatial-Temporal Smoothing
- Citation to related publication:
- Sun, H., Hua, Z., Ren, J., Zou, S., Sun, Y., & Chen, Y. (2020). Matrix Completion Methods for the Total Electron Content Video Reconstruction. arXiv preprint arXiv:2012.01618. and Zou, S., Ren, J., Wang, Z., Sun, H., & Chen, Y. (2021). Impact of Storm-Enhanced Density (SED) on Ion Upflow Fluxes During Geomagnetic Storm. Frontiers in Astronomy and Space Sciences, 162.
- Discipline:
- Science
-
- Creator:
- Hawes, Jason K, Johnson, Rebecca, Payne, Lindsey, Ley, Christian, Grady, Caitlin A., Domenech, Jennifer, Evich, Carly D., Kanach, Andrew, Koeppen, Allison, Roe, Kristen, Caprio, Audrey, Puente Castro, Jessica, LeMaster, Paige, and Blatchley, Ernest R. III
- Description:
- Global service-learning brings students, instructors, and communities together to support learning and community development across borders. In doing so, global service-learning practitioners act at the intersection of two fields: service-learning and international development. Critical scholarship in all three domains has highlighted the tensions inherent in defining and tracking “success” in community development. In response, service-learning and international development have turned considerable attention to documenting project characteristics, also known as best practices or success factors, which support equitable, sustainable community development. This database accompanies the article "Global Service-Learning - A systematic review of principle and practice," which presents a systematic synthesis of these fields’ best practices in the context of global service-learning. We propose 18 guiding principles for project design which aim to support practitioners in creating and maintaining justice-oriented, stakeholder-driven projects. This database contains the necessary reference material to trace the path of our analysis from abstract review to thematic synthesis. It also contains the final results of the thematic synthesis. To respect copyright restrictions, we have not made PDFs of all articles analyzed publicly accessible. Please contact the authors of this database or of the original article if you seek to access one of the articles we reference. For more information, see: Hawes, J. K., et al. “Global Service-Learning - A Systematic Review of Principle and Practice.” International Journal of Research on Service-Learning and Community Engagement 10, no. 1 (2022).
- Keyword:
- service-learning, international development, global service-learning, best practices, equitable development, higher education, community engagement, and student-friendly
- Citation to related publication:
- Hawes, J. K. (2021). Global Service-Learning—A systematic review of principle and practice. International Journal of Research on Service-Learning and Community Engagement, 10(1). https://doi.org/10.37333/001c.31383
- Discipline:
- International Studies and Other
-
- Creator:
- Yadav, Rajeev, Widom, Julia R, Chauvier, Adrien, and Walter, Nils G
- Description:
- These data were generated to study the conformational dynamic of fluoride riboswitch as an isolated RNA and in presence of RNA polymerase at different transcript lengths.
- Keyword:
- Fluoride riboswitch, smFRET, and conformational dynamics
- Citation to related publication:
- Yadav, R., Widom, J.R., Chauvier, A. et al. An anionic ligand snap-locks a long-range interaction in a magnesium-folded riboswitch. Nat Commun 13, 207 (2022). https://doi.org/10.1038/s41467-021-27827-y
- Discipline:
- Science
-
- Creator:
- University of Michigan Museum of Paleontology and CTEES
- Description:
- Reconstructed CT slices for a left dentary of Carpodaptes stonleyi (University of Michigan Museum of Paleontology catalog number UMMP VP 85286) as a series of TIFF images. Raw projections are not included in this dataset.
- Keyword:
- Paleontology, Fossil, CT, Carpolestidae, UMMP, University of Michigan Museum of Paleontology, Paleocene, CTEES, and ed7da511-d04c-fd32-09ef-0ea552966545
- Discipline:
- Science
-
- Creator:
- Vaskov, Alex K, Vu, Philip P, North, Naia, Davis, Alicia J, Kung, Theodore A, Gates, Deanna H, Cederna, Paul S, and Chestek, Cynthia A
- Description:
- The data was used to calibrate and simulate pattern recognition algorithms for the following publication: Surgically Implanted Electrodes Enable Real-Time Finger and Grasp Pattern Recognition for Prosthetic Hands (medRxiv 2020, IEEE TRO in review). Each data file is named as follows Px_PostureSet.csv. Where Px is the patient number. The 1 of 10 posture set contains individual finger and intrinsic thumb movements, the grasps posture set contains a fewer number of combined finger movements. P1’s calibration data for individual fingers is labelled 1 of 12 because it also includes two grasps, which were removed for analysis in the publication. The first column of each .csv file is the experiment time in seconds. The second column is the posture of the cue hand at that timestamp. The rest of the columns are the raw EMG data in microvolts sampled at 30KSps. A legend of the movement postures, each patients EMG channels, and suggested signal processing and filtering is included in DataLabellingAndProcessing.pdf
- Keyword:
- pattern recognition, electromyography, regenerative peripheral nerve interface, intramuscular electrodes, and myoelectric prostheses
- Citation to related publication:
- Surgically Implanted Electrodes Enable Real-Time Finger and Grasp Pattern Recognition for Prosthetic Hands A. K. Vaskov, P. P. Vu, N. North, A. J. Davis, T. A. Kung, D. H. Gates, P. S. Cederna, C. A. Chestek medRxiv 2020.10.28.20217273; doi: https://doi.org/10.1101/2020.10.28.20217273
- Discipline:
- Science and Engineering
-
University of Michigan Museum of Paleontology
User Collection- Creator:
- paleo-museum@umich.edu
- Description:
- TBD
- Discipline:
- Science
2Sub-collections0Works -
Invertebrate Paleontology
User Collection- Creator:
- paleo-museum@umich.edu
- Description:
- TBD
- Discipline:
- Science
0Works