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- Creator:
- Li, Jieming, Zhang, Leyou, Johnson-Buck, Alexander, and Walter, Nils G.
- Description:
- Traces from single-molecule fluorescence microscopy (SMFM) experiments exhibit photophysical artifacts that typically necessitate human expert screening, which is time-consuming and introduces potential for user-dependent expectation bias. Here, we have used deep learning to develop a rapid, automatic SMFM trace selector, termed AutoSiM, that improves the sensitivity and specificity of an assay for a DNA point mutation based on single-molecule recognition through equilibrium Poisson sampling (SiMREPS). The improved performance of AutoSiM is based on accepting both more true positives and fewer false positives than the conventional approach of hidden Markov modeling (HMM) followed by thresholding. As a second application, the selector was used for automated screening of single-molecule Förster resonance energy transfer (smFRET) data to identify high-quality traces for further analysis, and achieves ~90% concordance with manual selection while requiring less processing time. AutoSiM can be adapted readily to novel datasets, requiring only modest Transfer Learning.
- Keyword:
- deep learning, single-molecule fluorescence, total internal reflection microscopy, SiMREPS, smFRET, and Forster resonance energy transfer
- Citation to related publication:
- Li, J., Zhang, L., Johnson-Buck, A., & Walter, N. G. (2020). Automatic classification and segmentation of single-molecule fluorescence time traces with deep learning. Nature Communications, 11(1), 5833. https://doi.org/10.1038/s41467-020-19673-1 and Hayward, S., Lund, P., Kang, Q., Johnson-Buck, A., Tewari, M., Walter, N. (2018). Single-molecule microscopy image data and analysis files for "Ultra-specific and Amplification-free Quantification of Mutant DNA by Single-molecule Kinetic Fingerprinting" [Data set]. University of Michigan - Deep Blue. https://doi.org/10.7302/Z2CZ35DF
- Discipline:
- Science
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- Creator:
- Zhang, Yan, Fujian Normal University, Yang, Ping, Fujian Normal University, Tong, Chuan, Fujian Normal University, Zhang, Xinyan, Chinese Academy of Sciences, Changchun, Liu, Xingtu, Chinese Academy of Sciences, Changchun, Zhang, Shaoqing, Chinese Academy of Sciences, Changchun, Meyers, Philip. University of Michigan, and Gao, Chuanyu , Chinese Academy of Sciences, Changchun
- Description:
- A high-resolution study of bulk properties in a peat sequence from the Xinjiang Altai Mountains of northwestern China, has allowed reconstruction of local variations in peat properties and peat C and N accumulation rates (CAR and NAR) during the Holocene. Analyses of peat bulk density, loss on ignition, and concentrations of TOC and TN and their elemental ratios and stable isotopic values suggest that changes in peat-forming vegetation types during different parts of this epoch are the major factors responsible for the variations of peat properties in this sequence.
- Keyword:
- peat properties, stable carbon and nitrogen isotopes, carbon and nitrogen accumulation rates, and Altai Mountains of northwestern China
- Citation to related publication:
- Zhang, Y., Yang, P., Gao, C., Tong, C., Zhang, X., Liu, X., Zhang, S., & Meyers, P. A. (2020). Peat Properties and Holocene Carbon and Nitrogen Accumulation Rates in a Peatland in the Xinjiang Altai Mountains, Northwestern China. Journal of Geophysical Research: Biogeosciences, 125(12), e2019JG005615. https://doi.org/10.1029/2019JG005615
- Discipline:
- Science
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- Creator:
- Light, Charles X, Arbic, Brian K, Martin, Paige E, Brodeau, Laurent, Farrar, J Thomas, Griffies, Stephen M, Kirtman, Ben P, Laurindo, Lucas, Menemenlis, Dimitris, Molod, Andrea, Nelson, Arin D, Nyadjro, Ebenezer, O'Rourke, Amanda K, Shriver, Jay, Siqueira, Leo, Small, R Justin, and Strobach, Udi
- Description:
- The precipitation data itself is the output of the models/datasets that we analyze in our paper. Most of it is in .nc or .nc4 format, although we provide code to extract the data into time series .mat files. We used MATLAB to perform our analysis.
- Keyword:
- precipitation and power spectra
- Citation to related publication:
- Light, C.X., Arbic, B.K., Martin, P.E., Brodeau, L., Farrar, J.T., Griffies, S.M., Kirtman, B.P., Laurindo, L.C., Menemenlis, D., Molod, A., Nelson, A.D., Nyadjro, E., O'Rourke, A.K., Shriver, J.F., Siqueira, L., Small, R.J., Strobach, E. (2022). Effects of grid spacing on high-frequency precipitation variance in coupled high-resolution global ocean-atmosphere models. Climate Dynamics, https://doi.org/10.1007/s00382-022-06257-6
- Discipline:
- Science
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- Creator:
- Sean Sharp
- Description:
- Coastal wetlands intercept significant amounts of nitrogen (N) from watersheds, especially when surrounding land cover is dominated by agriculture and urban development. Through plant uptake, soil immobilization, and denitrification wetlands can remove excess N from flow through water sources and mitigate eutrophication of connected aquatic ecosystems. Excess N can also change plant community composition in wetlands, including communities threatened by invasive species. Understanding how variable hydrology and N loading impact wetland N removal and community composition can help attain desired management outcomes, including optimizing N removal and/or preventing invasion by non-natives. By using a dynamic, process-based ecosystem simulation model, we are able to simulate various levels of hydrology and N loading that would otherwise be difficult to manipulate. We investigate the effects of hydroperiod, hydrologic residence time, N loading, and the NH4+:NO3- ratio on both N removal and the invasion success of two non-native species (Typha x glauca or Phragmites australis) in temperate freshwater coastal wetlands using Mondrian, a process-based, wetland ecosystem simulation model. We found that when residence time increased, annual N removal increased up to 10-fold while longer hydroperiods also increased N removal, but only when residence time was >10 days and N loading was >30 g N m-2 y-1. N removal efficiency also increased with increasing residence time and hydroperiod, but was less affected by N loading. However, longer hydrologic residence time increased vulnerability of wetlands to invasion by both invasive plants at low to medium N loading rates where native communities are typically more resistant to invasion. This suggests a potential tradeoff between ecosystem services related to nitrogen removal and wetland invasibility. These results help elucidate complex interactions of community composition, N loading and hydrology on N removal, helping managers to prioritize N removal when N loading is high or controlling plant invasion in more vulnerable wetlands.
- Keyword:
- Mondrian, Simulation model, Coastal wetlands, Invasive species, and Ecosystem modeling
- Citation to related publication:
- Currie, W. S., Goldberg, D. E., Martina, J., Wildova, R., Farrer, E., & Elgersma, K. J. (2014). Emergence of nutrient-cycling feedbacks related to plant size and invasion success in a wetland community–ecosystem model. Ecological Modelling, 282, 69–82. https://doi.org/10.1016/j.ecolmodel.2014.01.010
- Discipline:
- Science
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- Creator:
- Chatterjee, Tanmay, Knappik, Achim, Sandford, Erin, Tewari, Muneesh, Choi, Sung Won, Strong, William B., Thrush, Evan P., Oh, Kenneth J., Liu, Ning, Walter, Nils G., and Johnson-Buck, Alexander
- Description:
- The sensitive measurement of specific protein biomarkers is important for medical diagnostics and research. However, existing methods for quantifying proteins use antibody probes that cannot distinguish between specific and nonspecific binding, limiting their sensitivity and specificity. This work establishes a method for distinguishing between specific binding to the target protein and nonspecific binding to assay surfaces using single-molecule kinetic measurements with dynamically binding probes. This is significant because it permits extremely sensitive protein measurements without requiring a high-affinity detection antibody or any washing steps, enabling streamlined and sensitive quantification of proteins even when no pair of high-quality, tightly binding antibodies is available.
- Keyword:
- biomarker detection, single molecule fluorescence, kinetic fingerprinting, total internal reflection microscopy, and super resolution microscopy
- Citation to related publication:
- Chatterjee, T., et al. Direct kinetic fingerprinting and digital counting of single protein molecules. Proc Natl Acad Sci USA, In Press.
- Discipline:
- Science
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- 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
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- Creator:
- Sergio E. Vidal-Luengo and Mark B. Moldwin
- Description:
- Multi-satellite tracking of solar wind dynamic pressure pulse observations through the Earth's magnetosphere enables us to distinguish local changes with propagation signatures.
- Keyword:
- Heliophysics, Magnetosphere, Dynamic pressure pulse, Magnetosphere, THEMIS, MMS, Cluster, SuperMag, and Heliophysics System Observatory
- Citation to related publication:
- Vidal-Luengo, S. E., & Moldwin, M. B. (2021). Global magnetosphere response to solar wind dynamic pressure pulses during northward IMF using the heliophysics system observatory. Journal of Geophysical Research: Space Physics, 126, e2020JA028587. https://doi.org/10.1029/2020JA028587
- Discipline:
- Science
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- Creator:
- Yiwen, Mei
- Description:
- The datasets of this archive are produced for a research project on the development of an advanced hydrologic modeling system for the St. Lawrence river basin. The outputted datasets from model simulations are in Netcdf 4 format. The author recommend using the netCDF Operators (NCO) program for data processing. For visualization and plotting, the author recommend using software like MATLAB, Python or R.
- Keyword:
- Hydrologic modeling, reanalysis product, St. Lawrence river, water balance, WRF-Hydro
- Discipline:
- Science
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- Creator:
- Burger, Laura L , Wagenmaker, Elizabeth R., Phumsatitpong, Chayarndorn , Olson, David P., and Moenter, Suzanne M.
- Description:
- Polycystic ovary syndrome (PCOS) is the most common form of infertility in women. The causes of PCOS are not yet understood and both genetics and early-life exposure have been considered as candidates. With regard to the latter, circulating androgens are elevated in mid-late gestation in women with PCOS, potentially exposing offspring to elevated androgens in utero; daughters of women with PCOS are at increased risk for developing this disorder. Consistent with these clinical observations, prenatal androgenization (PNA) of several species recapitulates many phenotypes observed in PCOS. There is increasing evidence that symptoms associated with PCOS, including elevated luteinizing hormone (LH) (and presumably gonadotropin-releasing hormone (GnRH)) pulse frequency emerge during the pubertal transition. We utilized translating ribosomal affinity purification coupled with RNA sequencing to examine GnRH neuron mRNAs from prepubertal (3wk) and adult female control and PNA mice. Prominent in GnRH neurons were transcripts associated with protein synthesis and cellular energetics, in particular oxidative phosphorylation. The GnRH neuron transcript profile was affected more by the transition from prepuberty to adulthood than by PNA treatment, however PNA did change the developmental trajectory of GnRH neurons. This included families of transcripts related to both protein synthesis and oxidative phosphorylation, which were more prevalent in adults than in prepubertal mice but were blunted in PNA adults. These findings suggest that prenatal androgen exposure can program alterations in the translatome of GnRH neurons, providing a mechanism independent of changes in the genetic code for altered expression. These are Microsoft Excel Files
- Keyword:
- GnRH Neuron TRAP Seq
- Citation to related publication:
- Unprocessed RNASeq data is available at Gene Expression Omnibus ( https://www.ncbi.nlm.nih.gov/gds) accession GSE155314.
- Discipline:
- Science
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- Creator:
- Davis Rabosky, Alison R. and Jantzi, Adrian
- Description:
- Video documentation of natural behavior in wild snakes is very rare, so film from opportunistic encounters of snake interactions is very valuable to scientific researchers. Our research team includes leading experts on this species of snake (the Western Groundsnake, Sonora semiannulata), so we worked with the observer to submit a formal description of the encounter to a peer-reviewed journal and make the information available to the broader research community.
- Keyword:
- Sonora semiannulata, ground snake, animal behavior, and male-male combat
- Citation to related publication:
- Jantzi A, CL Cox, AR Davis Rabosky, AT Holycross. 2021. SONORA SEMIANNULATA (Western Groundsnake). COMBAT. Herpetological Review 52(2): pg 434.
- Discipline:
- 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:
- 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
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- 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
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- Creator:
- Do, Hong X., Smith, Joeseph P., Fry, Lauren M., and Gronewold, Andrew D.
- Description:
- This data set contains a new monthly estimate of the water balance of the Laurentian Great Lakes, the largest freshwater system on Earth, from 1950 to 2019. The source codes and inputs to derive the new estimates are also included in this dataset. and ***ADDED 2024-02-27: The component net basins supply data "*NBSC_GLWBData.csv" in "output_ts_posterior.zip" need to be revised for further applications***
- Keyword:
- Laurentian Great Lakes, Bayesian inference, water levels, data assimilation, and water balance
- Citation to related publication:
- Do, H. X., Smith, J. P., Fry, L. M., & Gronewold, A. D. (2020). Seventy-year long record of monthly water balance estimates for Earth’s largest lake system. Scientific Data, 7(1), 276. https://doi.org/10.1038/s41597-020-00613-z, Gronewold, A. D., Smith, J. P., Read, L., & Crooks, J. L. (2020). Reconciling the water balance of large lake systems. Advances in Water Resources, 103505. https://doi.org/10.1016/j.advwatres.2020.103505 , and This version replaces the following deprecated dataset: Do, H.X., Smith, J.P., Fry, L.M., Gronewold, A.D. (2020). Monthly water balance estimates for the Laurentian Great Lakes from 1950 to 2019 [Data set]. University of Michigan - Deep Blue. https://doi.org/10.7302/0rsp-v195
- Discipline:
- Science
-
Estimates of the water balance of the Laurentian Great Lakes using the Large Lakes Statistical Water Balance Model (L2SWBM)
User Collection- Creator:
- Smith, Joeseph P., Fry, Lauren M., Do, Hong X., and Gronewold, Andrew D.
- Description:
- This collection contains estimates of the water balance of the Laurentian Great Lakes that were produced by the Large Lakes Statistical Water Balance Model (L2SWBM). Each data set has a different configuration and was used as the supplementary for a published peer-reviewed article (see "Citations to related material" section in the metadata of individual data sets). The key variables that were estimated by the L2SWBM are (1) over-lake precipitation, (2) over-lake evaporation, (3) lateral runoff, (4) connecting-channel outflows, (5) diversions, and (6) predictive changes in lake storage. and Contact: Andrew Gronewold Office: 4040 Dana Phone: (734) 764-6286 Email: drewgron@umich.edu
- Keyword:
- Great Lakes water levels, statistical inference, water balance, data assimilation, Great Lakes, Laurentian, Machine learning, Bayesian, and Network
- Citation to related publication:
- Smith, J. P., & Gronewold, A. D. (2017). Development and analysis of a Bayesian water balance model for large lake systems. arXiv preprint arXiv:1710.10161., Gronewold, A. D., Smith, J. P., Read, L., & Crooks, J. L. (2020). Reconciling the water balance of large lake systems. Advances in Water Resources, 103505., and Do, H.X., Smith, J., Fry, L.M., and Gronewold, A.D., Seventy-year long record of monthly water balance estimates for Earth’s largest lake system (under revision)
- Discipline:
- Science and Engineering
5Works -
Quantifying near-surface rock strength on a regional scale from hillslope stability models - dataset
- Creator:
- Townsend, Kirk F., Gallen, Sean F., and Clark, Marin K.
- Description:
- These datasets support the findings of Townsend et al. (2020). In this article, we quantify rock strength using two novel applications of hillslope stability models, resulting in estimates of cohesive and frictional strength at the spatial scale of small watersheds. We compare these results against the direct-shear test dataset here for validation of our approach. We find that cohesive strength is dependent on the original burial depth of the sedimentary rocks studied here. The low-temperature thermochronometry data was used to assess the magnitude of burial.
- Keyword:
- Thermochronology, Thermochronometry, Direct-Shear, Landslides, Rock Strength, Landscape Evolution, and Geomorphology
- Citation to related publication:
- Townsend, K.F., Gallen, S.F., & Clark, M.K., in press, Quantifying near-surface rock strength on a regional scale from hillslope stability models: Journal of Geophysical Research Earth Surface. https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020JF005665
- Discipline:
- Science
-
- Creator:
- James, David A. and Lokam, Nikhil
- Description:
- The object of this project is to provide researchers and students with a tool to allow them to develop an intuitive understanding of singular vectors and singular values. 2x2 matrices A with real entries map circles to ellipses; in particular, unit circles centered at the origin to ellipses centered at the origin. It is known that the points on the ellipse farthest from the origin correspond to the singular vectors of A. Users can use the GUI to enter matrices of their choice and explore to visually self-determine the singular vectors/values.
- Keyword:
- SVD, Singular Value Decomposition, Singular Vector, Singular Value, and Matrix
- Discipline:
- Science and Engineering
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- Creator:
- Swiger, Brian M., Liemohn, Michael W., and Ganushkina, Natalia Y.
- Description:
- We sampled the near-Earth plasma sheet using data from the NASA Time History of Events and Macroscale Interactions During Substorms mission. For the observations of the plasma sheet, we used corresponding interplanetary observations using the OMNI database. We used these data to develop a data-driven model that predicts plasma sheet electron flux from upstream solar wind variations. The model output data are included in this work, along with code for analyzing the model performance and producing figures used in the related publication. and Data files are included in hdf5 and Python pickle binary formats; scripts included are set up for use of Python 3 to access and process the pickle binary format data.
- Keyword:
- neural network, plasma sheet, solar wind, machine learning, keV electron flux, deep learning, and space weather
- Citation to related publication:
- Swiger, B. M., Liemohn, M. W., & Ganushkina, N. Y. (2020). Improvement of Plasma Sheet Neural Network Accuracy With Inclusion of Physical Information. Frontiers in Astronomy and Space Sciences, 7. https://doi.org/10.3389/fspas.2020.00042
- Discipline:
- Science and Engineering
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- Creator:
- Malhotra, Garima and Ridley, Aaron
- Description:
- This research aims to understand the importance of lower thermospheric atomic oxygen on the upper thermosphere. 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 show in this study that the correction of the lower boundary atomic oxygen yields better agreement between GITM and GUVI O/N2 in the upper thermosphere .
- Keyword:
- Lower Thermosphere Atomic Oxygen, Thermospheric Dynamics, Thermospheric composition and mixing, Lower-Upper Thermosphere Vertical Coupling, GITM - WACCMX coupling, and Global Ionosphere Thermosphere Model
- Citation to related publication:
- Malhotra, G., Ridley, A. J., Marsh, D. R., Wu, C., Paxton, L. J., & Mlynczak, M. G. (2020). Impacts of Lower Thermospheric Atomic Oxygen on Thermospheric Dynamics and Composition Using the Global Ionosphere Thermosphere Model. Journal of Geophysical Research: Space Physics, e2020JA027877. https://doi.org/10.1029/2020JA027877
- Discipline:
- Science
-
- Creator:
- Chen, Yuxi
- Description:
- We use the MHD with embedded particle-in-cell model (MHD-EPIC) to study the Geospace Environment Modeling (GEM) dayside kinetic processes challenge event at 01:50-03:00 UT on 2015-11-18, when the magnetosphere was driven by a steady southward IMF. In the MHD-EPIC simulation, the dayside magnetopause is covered by a PIC code so that the dayside reconnection is properly handled. We compare the magnetic fields and the plasma profiles of the magnetopause crossing with the MMS3 spacecraft observations. Most variables match the observations well in the magnetosphere, in the magnetosheath, and also during the current sheet crossing. The MHD-EPIC simulation produces flux ropes, and we demonstrate that some magnetic field and plasma features observed by the MMS3 spacecraft can be reproduced by a flux rope crossing event. We use an algorithm to automatically identify the reconnection sites from the simulation results. It turns out that there are usually multiple X-lines at the magnetopause. By tracing the locations of the X-lines, we find the typical moving speed of the X-line endpoints is about 70~km/s, which is higher than but still comparable with the ground-based observations.
- Keyword:
- MHD, PIC, and simulation
- Citation to related publication:
- Chen, Y., Tóth, G., Hietala, H., Vines, S. K., Zou, Y., Nishimura, Y., Silveira, M. V. D., Guo, Z., Lin, Y., & Markidis, S. (2020). Magnetohydrodynamic With Embedded Particle-In-Cell Simulation of the Geospace Environment Modeling Dayside Kinetic Processes Challenge Event. Earth and Space Science, 7(11), e2020EA001331. https://doi.org/10.1029/2020EA001331 and Chen, Yuxi, et al. "Magnetohydrodynamic with embedded particle-in-cell simulation of the Geospace Environment Modeling dayside kinetic processes challenge event." arXiv preprint arXiv:2001.04563 (2020). https://arxiv.org/abs/2001.04563
- Discipline:
- Science