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- Creator:
- Kharbush, Jenan J, Carter, Susan J, and Robinson, Rebecca S
- Description:
- Nitrogen availability is hypothesized to play a central role in cyanoHAB progression, as well as production of the N-rich toxin microcystin. Recent work implicated reduced N substrates like ammonium and dissolved organic N (DON) in promoting greater bloom biomass and longevity. To examine the relative importance of oxidized and reduced N substrates to phytoplankton during different bloom stages, we measured concentrations and natural abundance δ15N isotope values of dissolved N substrates and phytoplankton biomass throughout the entirety of the 2020 cyanoHAB in Western Lake Erie. This is the first data on DON concentrations and isotope values in Western Lake Erie. We measured nitrate concentrations and isotope values to compare with DON and also with particulate organic matter (POM) 15N isotope values. This dataset is described and analyzed in the publication, "Patterns in sources and forms of nitrogen during a freshwater cyanobacterial harmful algal bloom".
- Keyword:
- Dissolved organic nitrogen, cyanobacteria, nitrate, particulate organic matter, δ15N, stable isotopes
- Citation to related publication:
- Kharbush, Jenan J., Robinson, Rebecca S., Carter, Susan J. In revision. Patterns in sources and forms of nitrogen during a freshwater cyanobacterial harmful algal bloom. Limnology and Oceanography.
- Discipline:
- Science
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- Creator:
- Gultekin, Kayhan, Nyland, Kristina, Gray, Nichole, Fehmer, Greg , Huang, Tianchi, Sparkman, Matthew, Reines, Amy E., Greene, Jenny E., Cackett, Edward M., and Baldassare, Vivienne
- Description:
- The data were processed using the scripted VLA calibration pipeline ( https://science.nrao.edu/facilities/vla/data-processing/pipeline/scripted-pipeline) for the Common Astronomy Software Applications (CASA) package version 5.3.0. Imaging was performed using the TCLEAN task in CASA with standard parameters appropriate for broadband data with point-source emissison. We used Briggs weighting with robust parameters between 0 and 1. Self calibration was implemented manually on an as-needed basis for sufficiently bright sources with evidence for residual phase errors in the image plane.
- Keyword:
- active galactic nuclei, radio galaxies, fundamental plane, and intermediate-mass black holes
- Citation to related publication:
- Gultekin et al. (2022) MNRAS, in press
- Discipline:
- Science
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- Creator:
- Zhou, Peng and Mi, Zetian
- Description:
- Production of hydrogen fuel from sunlight and water offers one of the most promising pathways for carbon neutrality. Some solar hydrogen production approaches, e.g., photoelectrochemical water splitting, often requires corrosive electrolyte, limiting their performance stability and environmental sustainability. Alternatively, clean hydrogen can be produced directly from tap water, or seawater by wireless photocatalytic water splitting. The solar-to-hydrogen (STH) efficiency, however, is still lower than 3%. Herein, we have developed a unique strategy to overcome the efficiency bottleneck. A high STH efficiency of 9.2% was achieved by utilizing pure water, concentrated solar light, and visible-light-responsive InGaN photocatalyst. The success of this strategy was explained by the synergistic effects of promoting forward hydrogen-oxygen evolution and inhibiting the reverse hydrogen-oxygen recombination by operating at an optimal reaction temperature (~70 °C). Such an optimal temperature can be readily achieved by harvesting the previously wasted infrared light of the solar spectrum without other energy consumption. This temperature-dependent strategy also leads to the STH efficiencies of ~7% from the widely available tap water and seawater. A large-scale photocatalytic water splitting system with a natural solar light capacity of 257 W on a 4 cm × 4 cm photocatalyst wafer achieves a STH of 6.2% at ~70 oC. Our study offers a practical approach to produce hydrogen fuel efficiently from natural solar and water, overcoming some of the major barriers for green hydrogen economy.
- Keyword:
- photocatalysis, water splitting, and solar hydrogen
- Discipline:
- Science
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- Creator:
- Liemohn, Michael W, Adam, Joshua G, and Ganushkina, Natalia Y
- Description:
- Many statistical tools have been developed to aid in the assessment of a numerical model’s quality at reproducing observations. Some of these techniques focus on the identification of events within the data set, times when the observed value is beyond some threshold value that defines it as a value of keen interest. An example of this is whether it will rain, in which events are defined as any precipitation above some defined amount. A method called the sliding threshold of observation for numeric evaluation (STONE) curve sweeps the event definition threshold of both the model output and the observations, resulting in the identification of threshold intervals for which the model does well at sorting the observations into events and nonevents. An excellent data-model comparison will have a smooth STONE curve, but the STONE curve can have wiggles and ripples in it. These features reveal clusters when the model systematically overestimates or underestimates the observations. This study establishes the connection between features in the STONE curve and attributes of the data-model relationship. The method is applied to a space weather example.
- Keyword:
- space physics, statistical methods, and STONE curve
- Citation to related publication:
- Liemohn, M. W., Adam, J. G., & Ganushkina, N. Y. (2022). Analysis of features in a sliding threshold of observation for numeric evaluation (STONE) curve. Space Weather, 20, e2022SW003102. https://doi.org/10.1029/2022SW003102
- Discipline:
- Science
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- Creator:
- Larson, Joanna G and Weiner, Abraham
- Description:
- This dataset consists of 11 linear external morphological measurements from 1,614 adult frog individuals from 434 species that all naturally occur in the Western Hemisphere. We used these data to investigate patterns of multidimensional morphospace structure in frog assemblages along the latitudinal diversity gradient in the Americas. The measured traits are predictive of adult microhabitat use, diel activity patterns, locomotion, mating habitat, and diet.
- Keyword:
- functional traits, morphology, frog, anura, and amphibian
- Citation to related publication:
- Larson, JG, PO Title, and DL Rabosky. Expansion and packing of frog morphospace along the Western Hemisphere latitudinal diversity gradient revealed by functional traits. In prep
- Discipline:
- Science
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- Creator:
- Brian C. Weeks
- Description:
- Description: Each folder contains all of the data for a specific specimen; the folder names correspond to the University of Michigan Museum of Zoology catalog number for the specimen. Folders with a “-“ in the name are individual specimens that were photographed multiple independent times; the number following the “-“ indicates the repetition number (i.e. the folder named “UMMZ_242382-10” contains the tenth set of photographs for specimen UMMZ 242382). The photographs are necessary to train and test the Skelevision model, which is a computer vision approach to identifying and measuring elements of the skeleton (length of the tibiotarsus, tarsometatarsus, femur, humerus, ulna, radius, carpometacarpus, 2nd digit 1st phalanx, skull, and keel; the outer diameter of the sclerotic ring at its widest point; and the distance from the back of the skull to the tip of the bill). The data span 115 species of passerines across 79 genera from 59 families.
- Keyword:
- Bird skeleton, neural network, and functional traits
- Citation to related publication:
- Weeks, B.C., Zhou, Z., O’Brien, B., Darling, R., Dean, M., Dias, T., Hassena, G., Zhang, M., and Fouhey, D.F. 2022. A deep neural network for high throughput measurement of functional traits on museum skeletal specimens. Methods in Ecology and Evolution. https://doi.org/10.1111/2041-210X.13864
- Discipline:
- Science
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- Creator:
- Bressler, Alison and Blesh, Jennifer
- Description:
- This dataset contains three data files and three corresponding metadata files used in Bressler, A., and J. Blesh. 2022. Episodic N2O emissions following tillage of a legume-grass cover crop mixture. Biogeosciences. The file “Cover_crop_soil_N2O.xls” contains data organized by site, replicate block, and treatment for spring cover crop biomass, nitrogen and carbon content, and legume BNF; soil fertility characteristics including potentially mineralizable nitrogen, particulate organic matter stocks, concentrations, and nitrogen content; and cumulative nitrous oxide data. The file “Soil_properties.xls” contains baseline soil data organized by site and replicate block. The file “Daily_N2O.xls” contains daily nitrous oxide data organized by site, replicate block, treatment, and date. The corresponding metadata files: “Cover_crop_soil_N2O_metadata.xls”, and “Soil_properties_metadata.xls”, and “Daily_N2O_metadata.xls” provided detailed descriptions of all variables in each data set and any abbreviations used.
- Keyword:
- cover crops, legume-grass mixtures, nitrous oxide, particulate organic matter, soil organic matter.
- Citation to related publication:
- Bressler, A., and J. Blesh. 2022. Episodic N2O emissions following tillage of a legume-grass cover crop mixture. Biogeosciences.
- Discipline:
- Science
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- Creator:
- Cody H. Pham, Jason M. Tallant, J. Jordan Price, and David N. Karowe
- Description:
- Anthropogenic climate change will dramatically alter species distributions. The rate and magnitude of range shifts, however, will differ among taxa, resulting in altered patterns of co-occurrence and interspecific interactions. We examined potential climate-mediated breeding range shifts among North American wood-warblers (Parulidae), a speciose avian family likely to be especially impacted by such changes. We used publicly available species distribution model (SDM) range outputs to compare current ranges and patterns of sympatry among warbler species to future ranges and sympatry under 1.5 °C, 2.0 °C, and 3.0 °C of average global warming. We used these outputs to calculate average breeding range area, range overlap among species, number of sympatric species, and distances of breeding range shifts. We additionally calculated the number gained and lost sympatric interactions under each warming scenario.
- Keyword:
- wood-warbler, University of Michigan Biological Station (UMBS), Research Experience for Undergraduates (REU), climate change, interspecific, range shift, species distribution models, sympatric, and student-friendly
- Discipline:
- Science
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- 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
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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