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- Creator:
- Bougher, S. W. and Parkinson, C. D.
- Description:
- Understanding the state and composition of an exoplanetary atmosphere depends upon several parameters such as heating, cooling, mixing and reactions between constituent chemical species. Only a few types of atmospheric species can be detected remotely spectroscopically and only if their abundance is large enough to be detectable. In this initial study, we model the atmosphere of a Venus-like planet orbiting the M-type star GJ 436 to determine the global neutral temperature structure, winds, and energy balance as the radial distance of the planet from the star decreases.
- Keyword:
- Venus-like exoplanet, upper atmospheres , and heat balances
- Citation to related publication:
- C. D. Parkinson, S. W. Bougher, F. P. Mills, R. Hu, G. Gronoff, J. Li, A. Brecht, D. Adams, and Y. L. Yung. Venus as an Exoplanet: I. An Initial Exploration of the 3-D Energy Balance for a CO2 Exoplanetary Atmosphere Around an M-Dwarf Star, J. Geophysical Research, X, (2022). doi:....
- Discipline:
- 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:
- Liu, Meichen
- Description:
- The raw seismic records are downloaded from Incorporated Research Institutions for Seismology. The facilities of IRIS Data Services, and specifically the IRIS Data Management Center, were used for access to waveforms, related metadata, and/or derived products used in this study. The synthetic seismograms are generated by SPECMFEM3D_Globe software which was downloaded from the Computational Infrastructure for Geodynamics ( https://geodynamics.org/).
- Keyword:
- Composition and structure of the mantle, Phase transitions, North America, Body waves, and Computational seismology
- Discipline:
- Science
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Dynamical Heating in the Martian Thermosphere: Temperatures, Winds and Thermal Balances using M-GITM
- Creator:
- Bougher, S. W. and Pilinski, M. D.
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking systematic measurements of the densities and deriving temperatures in the upper atmosphere of Mars (between about 140 to 240 km above the surface) since late 2014. Wind measurement campaigns have also been conducted once per month for 5-10 orbits since 2016. These densities, temperatures and winds change with time (e.g. solar cycle, season, local time) and location, and sometimes fluctuate quickly. Global dust storm events are also known to significantly impact these density, temperature and wind fields in the Mars thermosphere. For the current project, in-situ measured winds and corresponding argon density derived temperatures are combined to trace the circulation patterns and investigate their convergence and divergence locations and impacts throughout the Mars thermosphere. M-GITM computed thermal balance terms are subsequently extracted to investigate the processes required to maintain the temperature distribution around the planet. For this work, Mars Year #33 (MY33) Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements have been obtained by the MAVEN team for this purpose (see these representative works: (Bougher et al., 2017; Stone et al., 2018; Benna et al., 2019). These temperature and wind fields are compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. Since the global circulation plays a role in the structure, variability, and evolution of the atmosphere, understanding the processes that drive the winds in the upper atmosphere of Mars also provides the needed context for understanding temperature distributions and underlying thermal balances throughout the atmosphere. Three dimensional M-GITM simulations for three of the four Mars cardinal seasons (Ls = 0, 90, 270) for MY33 were conducted for detailed comparisons with NGIMS temperature and wind distributions (Pilinski et al. 2022). Corresponding M-GITM datacubes used to extract these temperatures (plus winds) along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. A single README file is included that details the contents of each datacube file. In addition, this general README file summarizes the inputs and outputs of each M-GITM simulation interval used for this study. Finally, a basic version of the M-GITM code can be found on Github at https:/github.com/dpawlows/MGITM.
- Keyword:
- MAVEN, Mars thermosphere, global dynamics, and heat balances owing to winds
- Citation to related publication:
- Pilinski, M. D., K. J. Roeten, S. W. Bougher and M. Benna, Dynamical Heating in the Martian Thermosphere, Journal Geophysical Res., XXX, (forthcoming - 2022). doi: .....
- Discipline:
- Science
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- Creator:
- Song, Siliang and Zhang, Jianzhi
- Description:
- Fitness landscapes map genotypes to their corresponding fitness under given environments and allow explaining and predicting evolutionary trajectories. Of particular interest is the landscape ruggedness or the unevenness of the landscape, because it impacts many aspects of evolution such as the likelihood that a population is trapped in a local fitness peak. Although the ruggedness has been inferred from a number of empirically mapped fitness landscapes, it is unclear to what extent this inference is affected by fitness estimation error, which is inevitable in the experimental determination of fitness landscapes. Here we address this question by simulating fitness landscapes under various theoretical models, with or without fitness estimation error. We find that all eight examined measures of landscape ruggedness are overestimated due to imprecise fitness quantification, but different measures are affected to different degrees. We devise a method to use replicate fitness measures to correct this bias and show that our method performs well under realistic conditions. We conclude that previously reported fitness landscape ruggedness is likely upward biased owing to the negligence of fitness estimation error and advise that future fitness landscape mapping should include at least three biological replicates to permit an unbiased inference of the ruggedness.
- Keyword:
- adaptation, estimation error, evolution, NK model, Rough Mount Fuji model, and polynomial model
- Discipline:
- Science
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- Creator:
- Lester, Corey A, Al Kontar, Raed, and Chen, Qiyuan
- Description:
- The dataset contains images of pills inside a medication bottle from a top down view. The dataset was used to build an image classification model for predicting the national drug code (NDC) of the medication seen in the image. There are 13,955 images of 20 distinct NDC. The image data were used to create a machine learning algorithm which could predict the NDC.
- Keyword:
- Medication, Pills, and Image
- Discipline:
- Health Sciences
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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:
- Goodrich, Jaclyn M., Tang, Lu, Rodríguez-Carmona, Yanelli, Meijer, J L., Perng, Wei, Watkins, Deborah J., Meeker, John D. , Mercado-García, Adriana, Cantoral, Alejandra, Song, Peter X. , Téllez-Rojo, Martha M. , and Peterson, Karen E.
- Description:
- Phthalates are chemicals found in many products that humans are exposed to. Prenatal exposure to phthalates has been associated with adverse outcomes that are detected in childhood, adolescence, and even adulthood. In this study, we sought to identify subtle biological changes in the metabolome of children that were exposed to phthalates during gestation. We hypothesized that prenatal phthalate exposures would alter metabolic pathways related to adiposity and cardiometabolic health. The article is under review (citation to be added when paper is published). The data included here encompass all exposure, demographic, and untargeted metabolomics data needed for the analysis described in the manuscript.
- Keyword:
- Phthalates , Prenatal, and Metabolomics
- Citation to related publication:
- Goodrich J.M., Tang L.,Rodríguez-Carmona Y., Meijer J.L, Perng W., Watkins D.J., Meeker J.D., Mercado-García A., Cantoral A., Song P.X., Téllez-Rojo M.M., Peterson K.E. Trimester-specific phthalate exposures in pregnancy are associated with circulating metabolites in children. PLoS One. (Under revision – forthcoming.)
- Discipline:
- Other and Health Sciences
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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