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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
-
- Creator:
- Fuller, Jennifer, Rowan, Erin, Landgraf, Ava, Alofs, Karen, Foufopoulos, Johannes, and Gronewold, Andrew
- Description:
- This study investigates the rapid decline of black tern (Chlidonias niger) over eight years in one of Michigan’s largest colonies, Lake St. Clair. 1. Nesting Success Model: A multiple logistic regression with a binomial (logit-link) fit using the glm() function from the ‘stats’ package in R (55) to determine the influence of habitat and biological predictors on nesting survival. 2. ArcMap visualization of Nesting Success: To visualize the geographic extent of the habitat’s potential to predispose nests’ vulnerability, the coefficients and intercept from our selected GLM were applied to raster layers in ArcMap using the Raster Calculator Tool. 3. Population Change & Habitat Extent: To quantify sub-colony breeding pair population size and their response to changes in sub-colony habitat in the geospatial model, we applied a general linear mixed model (GLMM) using the lmer() function from the ‘lme4’ package in R (55). Predictor variables were chosen a priori, and included the area of open water, uninhabitable vegetation (NDVI>0.72), any habitable area, and area with >50% hatch success.
- Keyword:
- black terns, wetlands, ecology, climate change, lake levels, Great Lakes, waterbirds, ornithology, general linear model, geospatial, GIS, nesting success, avian, and breeding
- Citation to related publication:
- Fuller, J., Rowan, E., Landgraf, A., Alofs, K., Foufopoulos, J., Gronewold, A., (2021). Collapse of a Black Tern Colony (Chlidonias niger) as a Result of Climate Change Driven Lake-Level Extremes and Anthropogenic Habitat Alteration [Data set]. University of Michigan - Deep Blue. and Fuller, J., et al. (2021). Shorebird colony collapses under climate driven lake-level rise and anthropogenic stressors. Forthcoming.
- Discipline:
- Science
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- Creator:
- Lynch, Erin and van der Pluijm, Ben
- Description:
- High-resolution, low-angle XRD analysis of oriented clay samples (.txt files) and TC/EA, Mass Spectronometric analysis of oxygen and hydrogen isotopes (.xslx files)
- Keyword:
- fault gouge and geofluids
- Citation to related publication:
- In submission
- Discipline:
- Science
-
- Creator:
- Herrick, Etienne M
- Description:
- This data was produced as part of field experiment investigating the extent, drivers, and consequences of functional trait variation in cover crops. Specifically, we studied the role of intraspecific trait variation in explaining interactions between species in cover crop mixtures, and whether and how intraspecific trait variation improves understanding of relationships between functional traits and ecosystem services from cover crops.
- Keyword:
- agroecology, cover crops, functional diversity, functional traits, intraspecific trait variation, ecosystem services, nitrogen, species interactions, and student-friendly
- Citation to related publication:
- Herrick, E., and Blesh, J. (2021) Intraspecific trait variation improves understanding and management of cover crop outcomes. Ecosphere.
- Discipline:
- Science
-
- Creator:
- Sun, Xin, Zhang, Kehui, Marks, Rebecca, Karas, Zachary, Eggleston, Rachel, Nickerson, Nia, Yu, Chi-Lin, Wagley, Neelima, Hu, Xiaosu, Caruso, Valeria, Tardif, Twila, Satterfield, Teresa, Chou, Tai-Li, and Kovelman, Ioulia
- Description:
- In a broad sense, this dataset explores morphological and phonological processing in English monolinguals and two bilingual populations, Chinese-English and Spanish-English, using a battery of standardized and self-developed behavioral measures, as well as fNIRS neuroimaging.
- Citation to related publication:
- Sun X, Zhang K, Marks R, Karas Z, Eggleston R, Nickerson N, Yu CL, Wagley N, Hu X, Caruso V, Chou TL, Satterfield T, Tardif T, Kovelman I. Morphological and phonological processing in English monolingual, Chinese-English bilingual, and Spanish-English bilingual children: An fNIRS neuroimaging dataset. Data Brief. 2022 Mar 12;42:108048. doi: 10.1016/j.dib.2022.108048. PMID: 35313503; PMCID: PMC8933821.
- Discipline:
- Science
-
- Creator:
- Brang, David and Karthik, Ganesan
- Description:
- Data were acquired from 21 patients with intractable epilepsy undergoing clinical evaluation using iEEG. Patients ranged in age from 15-58 years (mean = 37.1, SD = 12.8) and included 10 females. Across all patients, data was recorded from a total of 1367 electrodes. Each participant were presented with multiple trials of auditory only and congruent audio-visual stimuli. On each trial a single phoneme was presented to the participant. Three variants of the tasks were used with each variant consisting of a different set of phonemes (variant A: /ba/ /da/ /ta/ /tha/, variant B: /ba/ /da/ /ga/, variant C: /ba/ /ga/ /ka/ /pa/). Trials were presented in a random order and phonemes were distributed uniformly across conditions. While conditions were matched in terms of trial numbers, participants completed a variable number of trials (based on task variant and the number of blocks completed). All provided data has been resampled to 1024 Hz during initial stages of processing for all participants. Data has been referenced in a bipolar fashion (signals subtracted from each immediately adjacent electrode in a pairwise manner) to ensure that the observed signals were derived from maximally local neuronal populations. The preprocessing steps followed have been described in the detailed description document in the attached materials. and The dataset zip folder consists of three main sub-folders: 1) Electrodes: This folder provides details regarding the individual electrodes for each subject, their MNI coordinates as well as their MNI vertices information according to freesurfer parcellations. This folder also consists of images of the physical location of each of the electrode sets. 2) Processed: This folder contains preprocessed data in all three frequencies (theta, beta and high gamma power) for individual subjects and the corresponding vertex locations for each of the electrodes from which their data was recorded. The images subfolder also contains figures provided in the main manuscript. 3) MatlabCodes: This folder contains all the matlab scripts required to reproduce the results provided in the main manuscript. LME_AvsAV_Main_Windows.m is the main file that an user has to run to reproduce the results.
- Keyword:
- Cognitive Neuroscience, Neuroscience, Perception, and Mixed Effects Models
- Citation to related publication:
- Ganesan, K., Plass, J., Beltz, A. M., Liu, Z., Grabowecky, M., Suzuki, S., ... & Brang, D. (2020). Visual speech differentially modulates beta, theta, and high gamma bands in auditory cortex. bioRxiv. https://doi.org/10.1101/2020.09.07.284455
- Discipline:
- Science
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- Creator:
- Moldwin, Mark B. and O'Brien, Paul
- Description:
- A new empirical model of the plasmapause location has been developed using density data from the plasma wave receiver onboard the CRRES spacecraft for nearly 1000 orbits. The “plasmapause” is identified here as the innermost sharp gradient in density (change of a factor of 5 in <0.5 L). Such a sharp gradient was observed on 73% of the CRRES inbound and outbound orbits that returned data. The plasmapause location is expressed as a linear function of Kp (previous 12 hour maximum) and local time. The model gives the linear best fit location of the plasmapause as well as the standard deviations of the model parameters.
- Keyword:
- Plasmapause and Plasmasphere
- Citation to related publication:
- Moldwin, M. B., Downward, L., Rassoul, H. K., Amin, R., and Anderson, R. R. (2002), A new model of the location of the plasmapause: CRRES results, J. Geophys. Res., 107( A11), 1339, doi:10.1029/2001JA009211 and O'Brien, T. P., and Moldwin, M. B. (2003), Empirical plasmapause models from magnetic indices, Geophys. Res. Lett., 30, 4, 1152. doi:10.1029/2002GL016007
- Discipline:
- Science
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- Creator:
- Zhang, Yizhen
- Description:
- We collected hours of functional magnetic resonance imaging data from human subjects listening to natural stories. We developed a predictive model of the voxel-wise response and further applied it to thousands of new words to understand how the brain stores and connects different concepts. and This is a dataset for the paper: Zhang, Y., Han, K., Worth, R., & Liu, Z. (2020). Connecting concepts in the brain by mapping cortical representations of semantic relations. Nature communications, 11(1), 1-13. https://doi.org/10.1038/s41467-020-15804-w. This project is also documented at https://osf.io/eq2ba/.
- Keyword:
- fMRI, natural story comprehension, neural encoding, semantic processing, word relations, and naturalistic stimuli
- Citation to related publication:
- Zhang, Y., Han, K., Worth, R., & Liu, Z. (2020). Connecting concepts in the brain by mapping cortical representations of semantic relations. Nature communications, 11(1), 1-13. https://doi.org/10.1038/s41467-020-15804-w
- Discipline:
- Science
-
- Creator:
- Brasch, Jonathan M, Elipot, Shane, and Arbic, Brian
- Description:
- For Drifters, HYCOM, MITgcm: Spectra and kinetic energy files. Please see readme.txt for a description of all data and code contained here. and - Compare kinetic energies (KE) of high-resolution global ocean models estimated from rotary spectra to KE in surface drifter observations. - Near-inertial KE is closer to drifter observations in models with frequently updated wind forcing - Internal tide KE is closer to drifter observations in models with topographic wave drag
- Keyword:
- oceanography, rotary spectra, kinetic energy, sea surface velocity, and drifters
- Citation to related publication:
- Elipot, S., Lumpkin, R., Perez, R. C., Lilly, J. M., Early, J. J., & Sykulski, A. M. (2016). A global surface drifter data set at hourly resolution. Journal of Geophysical Research: Oceans, 121(5), 2937–2966. https://doi.org/10.1002/2016JC011716
- Discipline:
- Science
-
- Creator:
- Boles, Austin H and van der Pluijm, Ben
- Description:
- This data was generated as a chapter in the dissertation of Austin Boles.
- Keyword:
- authigenic illite, hydrogen isotopes, and 40Ar/39Ar isotopic analysis
- Citation to related publication:
- Boles, A., & Pluijm, B. van der. (2020). Locally Derived, Meteoric Fluid Infiltration Was Responsible for Widespread Late Paleozoic Illite Authigenesis in the Appalachian Basin. Tectonics, 39(7), e2020TC006137. https://doi.org/10.1029/2020TC006137
- Discipline:
- Science