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- Creator:
- Townsend, Kirk F., Clark, Marin K., and Niemi, Nathan A.
- Description:
- These datasets support the findings of Townsend et al. (in review) investigating the timing of faulting relative to changes in the orientation of the North American-Pacific plate boundary. Coeval with development of an oblique plate boundary segment (i.e. the “Big Bend” of the San Andreas fault), active shortening is inferred to have initiated at ~5 Ma in the Western Transverse Ranges (WTR). However, new low-temperature thermochronometric transects yield Miocene to Pleistocene apatite (U-Th-Sm)/He cooling ages and partially reset zircon (U-Th)/He ages. Inverse thermal modelling indicate that reverse faulting initiated as early as 10 Ma, several million years prior to our current understanding of the timing of the Big Bend. New and existing thermochronometry data delineate the WTR as the locus of rapid post-Miocene exhumation, and demonstrate that similar exhumation is not present in the broader region surrounding the Big Bend. We posit that reverse faulting is localized in the WTR because of a weak underlying lithosphere and predates the more recent geometric anomaly of the restraining bend in the transform margin.
- Keyword:
- Reverse faults, Fault initiation, Fault propagation, Low-temperature thermochronometry, Western Transverse Ranges, and San Andreas Fault
- Citation to related publication:
- Townsend, K. F., Clark, M. K., & Niemi, N. A., in review, Reverse faulting within a continental plate boundary transform system. Tectonics
- Discipline:
- Science
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- Creator:
- Esquivel, Amanda
- Description:
- The survey questions were organized in the following categories: - demographics: age, gender identity, race, ethnicity, and country of birth - education: degree type and date earned, STEM area - employment field, employer information, title, job duties - measures of productivity including research, grant, patents and site/workplace/lab access - work/life balance: responsibilities and duties Questions regarding productivity and work/life balance queried pre and post COVID experiences. Many questions solicited optional comments and the relevant ones are presented as a table.
- Discipline:
- Science
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- Creator:
- University of Michigan Museum of Paleontology and CTEES
- Description:
- Reconstructed CT slices for postcrania (cervical vertebrae, L+R humerus, R scapula, R coracoid, L femur) of Stylemys nebrascensis (University of Michigan Museum of Paleontology catalog number UMMP VP 9318) as a series of TIFF images. Raw projections are not included in this dataset. The reconstructed slice data from the scan are offered here as a series of unsigned 16-bit integer TIFF images. The upper left corner of the first image (*_0000.tif) is the XYZ origin.
- Keyword:
- Paleontology, Fossil, CT, Testudinidae, UMMP, University of Michigan Museum of Paleontology, Oligocene, CTEES, and c38728f5-6f38-d862-7bcf-9745e69db222
- Citation to related publication:
- University of Michigan Museum of Paleontology, CTEES. (2022). CT Data of UMMP VP 9318, Stylemys nebrascensis skull [Data set], University of Michigan - Deep Blue Data. https://doi.org/10.7302/74pd-kb09
- Discipline:
- Science
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- Creator:
- University of Michigan Museum of Paleontology and CTEES
- Description:
- Reconstructed CT slices for HOLOTYPE jaw frag. of Trilophosaurus buettneri (University of Michigan Museum of Paleontology catalog number UMMP_VP_2338) as a series of TIFF images. Raw projections are not included in this dataset. The reconstructed slice data from the scan are offered here as a series of unsigned 16-bit integer TIFF images. The upper left corner of the first image (*_0000.tif) is the XYZ origin.
- Keyword:
- Paleontology, Fossil, CT, Trilophosauridae, UMMP, University of Michigan Museum of Paleontology, L. Triassic, CTEES, and 80ea727c-798c-5382-2ae7-eff7f13b66af
- Citation to related publication:
- Case, E.C. (1928) Indications of a Cotylosaur and of a New Form of Fish from the Triassic Beds of Texas, with Remarks on the Shinarump Conglomerate. Contributions from the Museum of Paleontology, University of Michigan Vol. 3(1):1-14. https://hdl.handle.net/2027.42/48181
- Discipline:
- Science
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- Creator:
- Malhotra, Garima and Ridley, Aaron
- Description:
- This research aims to understand the influence of lower thermospheric atomic oxygen ([O]) and dynamics on the thermospheric Semi Annual Oscillation (SAO). [O] number densities between 95-100 km from WACCM-X are much closer to the observations from SABER instrument on TIMED satellite as compared to those from MSIS. We compare the phase and amplitude of SAO from different simulations with empirical models and observational datasets, and explore different mechanisms that can improve the SAO in IT models.
- Keyword:
- Semi Annual Oscillation, SAO, T-I SAO, Thermospheric Dynamics, Thermospheric Semi Annual Oscillation, WACCM-X coupling with GITM, Global Ionosphere Thermosphere Model, WACCM-X, Whole Atmosphere Model, Vertical coupling, Meridional Circulation, Annual Oscillation, Thermospheric Intra-Annual Variations, and Semiannual Oscillation
- Citation to related publication:
- Malhotra, G., Ridley, A., Jones, M., (2021) Impacts of Lower Thermospheric Atomic Oxygen and Dynamics on Thermospheric Semiannual Oscillation using GITM and WACCM-X, Journal of Geophysical Research: Space Physics
- Discipline:
- Science
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- Creator:
- Bougher, S. W. (University of Michigan) and Brecht, A. S. (NASA Ames Research Center)
- Description:
- This work examines the planetary wave-induced variability within the upper mesosphere/lower thermosphere of Venus by utilizing the Venus Thermospheric General Circulation Model (VTGCM). Rossby and Kelvin wave perturbations are driven by variations in the geopotential height of the VTGCM lower boundary (~70 km). A suite of simulations was conducted to examine the impact of the individual and combined waves propagating from two different lower boundary conditions (uniform and varying). The Kelvin wave is the more dominant wave which produces the most variability, as was shown in Hoshino et al., 2012. The combination of the Kelvin and Rossby waves provides a maximum temperature amplitude of 13 K at 92 km and maximum zonal wind amplitude of 23 m/s at 102 km. The combined waves overall are able to propagate up to 125 km. Most of the variation within the temperature, winds, and composition occurs between 70 km and 110 km. The varying lower boundary increases the magnitude of the wave deposition but weakly changes the propagation altitude. The thermal variation due to the planetary waves does not reproduce most observed variations. The simulated O2 IR nightglow emission is sensitive to the waves with respect to intensity and local time, but lacks latitudinal variation. The integrated intensity ranges from 1.2 MR to 1.65 MR and the local time ranges from 0.33 local time to 23.6 local time. Overall, planetary waves do affect the atmospheric structure, but there are still observed large variations that planetary waves alone cannot explain (i.e. thermal structure).
- Keyword:
- Venus, planetary waves, upper mesophere, lower thermosphere, and O2 nightglow
- Citation to related publication:
- Brecht, A. S., Bougher, S. W., Shields, D., & Liu, H.-L. (2021). Planetary-scale wave impacts on the Venusian upper mesosphere and lower thermosphere. Journal of Geophysical Research: Planets, 126, e2020JE006587. https://doi.org/10.1029/2020JE006587
- Discipline:
- Science
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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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Profiles of near-surface rock mass strength across gradients in erosion, burial, and time [Data set]
- Creator:
- Townsend, Kirk F, Clark, Marin K, and Zekkos, Dimitrios
- Description:
- These datasets support the findings of Townsend et al. (2020). In this article, we project profiles of rock mass shear strength into the shallow subsurface (~30 m depth) using the Hoek and Brown criterion with Geological Strength Index (GSI) observations of outcrop structure and surface conditions, and Schmidt hammer rebound values of intact (unfractured) rock hardness. We compare these projected rock mass shear strength profiles to shear-wave velocity profiles collected using shallow geophysical arrays. We evaluate our methods in the Western Transverse Ranges of southern California, which exhibit strong gradients in the depth of latest-Mesozoic through Cenozoic sedimentary rocks exposed at the surface today, and in erosion rates quantified from catchment-average cosmogenic radionuclide concentrations and low-temperature apatite and zircon (U-Th)/He thermochronometry. We find that stratigraphic age and burial depth exerts the strongest apparent control on rock strength and S-wave velocities, likely due to diagenetic changes associated with burial. For rocks of the same age and inferred burial history, we observe that shear strength and S-wave velocities are positively correlated with erosion rate. We suggest that increasing erosion rates cause decreased residence time of rock masses within the critical zone, resulting in less weathered rocks.
- Keyword:
- rock strength, seismic, and erosion rate
- Citation to related publication:
- Townsend, K. F., Clark, M. K., & Zekkos, D. (2021). Profiles of Near-Surface Rock Mass Strength Across Gradients in Burial, Erosion, and Time. Journal of Geophysical Research: Earth Surface, 126(4), e2020JF005694. https://doi.org/10.1029/2020JF005694
- Discipline:
- Science
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- Creator:
- Lee, Dahee, Panicker, Veena, and Landis-Lewis, Zach
- Description:
- We use the term “performance summary display” (PSD) to mean a kind of visualization that relates performance levels to other types of information. In the context of healthcare organizations, PSDs are intended to be communicated to a healthcare professional, team, or organization. and Displays were identified, classified, and elements counted and coded. The performance summary display ontology provides a set of descriptions of components of displays that have been used to annotate performance feedback visualizations.
- Keyword:
- Performance
- Citation to related publication:
- Lee, D., Panicker, V., Gross, C., Zhang, J., & Landis-Lewis, Z. (2020). What was visualized? A method for describing content of performance summary displays in feedback interventions. BMC medical research methodology, 20(1), 90. https://doi.org/10.1186/s12874-020-00951-x
- Discipline:
- Health Sciences and Science
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- Creator:
- Umaña, María Natalia and Arellano, Gabriel
- Description:
- The objective of this study was to examine the existence of congruent tree growth responses to different extreme climatic events –hurricanes and drought–affecting tropical wet forests.
- Keyword:
- Dendrometers , El Niño Southern Oscillation (ENSO), Hurricane Maria, Puerto Rico, and Tropical Forests
- Citation to related publication:
- Umaña, M.N.and Arellano G. In press. Legacy effects of drought on tree growth responses to hurricanes. Ecography. https://doi.org/10.1111/ecog.05803
- Discipline:
- Science