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- Creator:
- Allen, David N, Vandermeer, John, Dick, Christopher W, Perfecto, Ivette, and Burnham, Robyn J
- Description:
- These data are in the standard ForestGEO format. Each of the three censuses has its own text file. Within that file each row represents a stem measured in that census. Species information can be found in the species file. The personnel responsible for this work can be found in the personnel file. See the readme file for more information.
- Keyword:
- Forest ecology, Oak-hickory forest, Mesophication, and Invasive species
- Citation to related publication:
- Allen, D, CW Dick, RJ Burnham, I Perfecto, and J Vandermeer. The Michigan Big Woods research plot at the Edwin S. George Reserve, Pinckney, MI, USA. Occasional Papers of the Museum of Zoology. In review.
- Discipline:
- Science
- Creator:
- Yadav, Rajeev, Widom, Julia R, Chauvier, Adrien, and Walter, Nils G
- Description:
- These data were generated to study the conformational dynamic of fluoride riboswitch as an isolated RNA and in presence of RNA polymerase at different transcript lengths.
- Keyword:
- Fluoride riboswitch, smFRET, and conformational dynamics
- Citation to related publication:
- Yadav, R., Widom, J.R., Chauvier, A. et al. An anionic ligand snap-locks a long-range interaction in a magnesium-folded riboswitch. Nat Commun 13, 207 (2022). https://doi.org/10.1038/s41467-021-27827-y
- Discipline:
- Science
- Creator:
- Bougher, S. W. (CLaSP Department, University of Michigan)
- 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 are also conducted once per month for 5-10 orbits. 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, the inert light species helium is used to trace the circulation patterns and constrain wind magnitudes throughout the Mars thermosphere. Presently, more than 6 years of Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements of helium densities have been obtained by the MAVEN team (e.g. Elrod et al., 2017; 2021; Gupta et al., 2021). Measured helium distributions 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 helium distributions and how the atmosphere behaves as a whole system. Three dimensional M-GITM simulations for the Mars four cardinal seasons (Ls = 0, 90, 180, 270, for Mars Year 33) were conducted for detailed comparisons with NGIMS helium and CO2 distributions (Gupta et al. 2021). The M-GITM datacubes used to extract these densities (plus winds) along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. README files are also provided for each datacube, detailing the contents of each file. In addition, a general README file is provided that summarizes the inputs and outputs of the M-GITM code simulations for this study. Finally, a basic version of the M-GITM code can be found on Github at https:/github.com/dpawlows/MGITM.
- Keyword:
- Mars, MAVEN Spacecraft Mission, Mars Thermosphere, Helium Density Distributions, and Neutral Gas and Ion Mass Spectrometer (NGIMS)
- Citation to related publication:
- Gupta, N., N. V. Rao, S. W. Bougher, and M. K. Elrod, Latitudinal and Seasonal Asymmetries of the Helium Bulge in the Martian Upper Atmosphere J. Geophys. Res., 126, XXXX-XXXX. doi:10.1002/2021JEXXXXXX
- Discipline:
- Engineering and Science
- Creator:
- Vo, Thi and Glotzer, Sharon C.
- Description:
- The goal of this project is to develop a first principle driven approach for predicting the self-assembly behavior of entropically driven crystallization. We first developed a set of mean-field theoretical framework that captures the relevant energetic contributions to the assembly process and then evaluate relevant terms within our framework to determine the excess free energy of formation for each lattice (matlab/octave codes). We then validate theoretical predictions of relevant features like shape and bonding orbitals using standard MD simulations using HOOMD-Blue (simulation scripts). and This research was supported by the Office of the Undersecretary of Defense for Research and Engineering (OUSD(R&E)), Newton Award for Transformative Ideas during the COVID-19 Pandemic, Award number HQ00342010030.
- Keyword:
- Self-Assembly, Entropy, Thermodynamics, Simulations, and Theory
- Citation to related publication:
- Vo, T., & Glotzer, S. C. (2021). Microscopic Theory of Entropic Bonding for Colloidal Crystal Prediction. ArXiv:2107.02081 [Cond-Mat]. http://arxiv.org/abs/2107.02081
- Discipline:
- Science
- Creator:
- Majeed, Tariq
- Description:
- We use our 1-D chemical diffusive model to quantify the physical processes necessary to interpret the day-side ionospheric measurements acquired with radio occultation techniques at the southern high-latitude region of Mars, where the crustal magnetic field is strong and near-vertical in orientation. To interpret the measured ionospheric structure at altitudes where plasma transport dominates, we find it is necessary to impose field-aligned vertical plasma drifts caused by the motion of neutral winds. The most interesting finding of this study is that both upward (between 110 m/s and 150 m/s) and downward (between -55 m/s and -120 m/s) drifts are required to maintain the topside Ne distribution comparable with the measured distribution. We also find that a fixed velocity boundary condition at the upper boundary with a sizeable upward ion velocity is needed to encounter any unexpected ion accumulation in the topside ionosphere to limit the Martian ion outflow. Given the complex nature of neutral dynamics and its relationship to plasma transport processes over magnetic anomalies, we consider that a simple model, such as we have developed, is still capable of yielding valuable insights relating to the neutral wind system at Mars.
- Keyword:
- Ionosphere of Mars
- Discipline:
- Science
- Creator:
- Hille, Madeline M., Clark, Marin K., Gronewold, Andrew D., West, A. Joshua, Zekkos, Dimitrios , and Chamlagain, Deepak
- Description:
- This dataset supports the findings of Hille et al. (2021, in review) in Geophysical Research Letters. In this article, we present a multivariate analysis of extreme storm events that occur during the Indian summer monsoon over the Himalayan Range in central Nepal. We resolve storm events at sub daily durations by merging NASA’s Global Precipitation Mission (GPM) Integrated Multi-satellitE Retrievals for GPM (IMERG) 30-minute, gridded 0.1x0.1-degree precipitation product with local rain gauges operated by the Nepal Department of Hydrology and Meteorology (DHM) and the International Centre for Integrated Mountain Development (ICIMOD). We quantify spatial variability in extreme rainfall by isolating storms over a specific intensity threshold and pairing a principal components analysis with a K-means clustering approach to group storms of similar characteristics. and We find that frequent and intense storms occur over the forefront of the central Himalayan range and coincide with a locus of monsoon-driven landslide density. This pattern agrees with observations of elevated annual precipitation volumes near the Himalayan physiographic transition from low to high relief (Bookhagen and Burbank, 2010), and is consistent with orographically-influenced rainfall over other mountain ranges (Marra et al., 2021). In addition to presenting novel methodology to quantifying storm variability, our results highlight the strong orographic effect on precipitation intensity and duration, as well as an association of shallow bedrock landsliding frequency with intense precipitation.
- Keyword:
- orographic rainfall, multivariate analysis, extreme rainfall events, and rainfall-triggered landslides
- Citation to related publication:
- Hille et al. (2021, in review). The orographic influence on storm variability, extreme rainfall characteristics and rainfall-triggered landsliding. Geophysical Research Letters. Forthcoming
- Discipline:
- Science
1207. Imaging the reduction of uranyl on Fe-bearing minerals surfaces using in situ electrochemical AFM
- Creator:
- Kim, YoungJae, Marcano, Maria C., Kim, Sooyeon, and Becker, Udo
- Description:
- The main objective of this research is to integrate electrochemical and microscopic approaches to understand reaction mechanisms and pathways of the uranyl reduction and nucleation mediated by magnetite and ilmenite. and This experimental data reveal how natural iron minerals mediate redox reactions of redox sensitive elements. We measure electrochemical responses of dissolved uranyl ions (UO22+) to potentials in the presence of organic molecules. The atomic force microscopic (AFM) images show nucleation of reduced uranyl on ilmenite (FeTiO3) as a function of potential.
- Keyword:
- electrochemical AFM and uranium reduction
- Citation to related publication:
- Kim, Y., Marcano, M. C., Kim, S., & Becker, U. (2021). Reduction of uranyl and uranyl-organic complexes mediated by magnetite and ilmenite: A combined electrochemical AFM and DFT study. Geochimica et Cosmochimica Acta, 293, 127–141. https://doi.org/10.1016/j.gca.2020.10.016 and Walker S. M., Marcano M. C., Bender W. M. and Becker U. (2016) Imaging the reduction of chromium (VI) on magnetite surfaces using in situ electrochemical AFM. Chemical Geology 429, 60-74.
- Discipline:
- Science
- Creator:
- University of Michigan, Division of Herpetology, Davis Rabosky, Alison R, Larson, Joanna G, Moore, Talia Y, and Curlis, John David
- Description:
- This dataset includes dorsal and ventral photographs of Neotropical snakes collected in the Peruvian Amazon. These data were collected to survey and examine the diversity in color pattern evolution in Neotropical snakes.
- Keyword:
- snake, color, serpentes, and Peru
- Citation to related publication:
- (work in progress, not yet submitted)
- Discipline:
- Science
- 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
- Creator:
- Davis Rabosky, Alison R., Moore, Talia Y., Sánchez-Paredes, Ciara M., Westeen, Erin P., Larson, Joanna G., Sealey, Briana A., and Balinski, Bailey A.
- Description:
- Animals in nature use diverse strategies to evade or deter their predators, including many vivid behavioural displays only qualitatively described from field encounters with natural predators or humans. Within venomous snake mimicry, stereotyped anti-predator displays are suggested to be a critical component of the warning signal given by toxic models and thus under strong selection for independent convergence in mimetic species. However, no studies have systematically quantified variation in snake anti-predator displays across taxonomically broad clades to test how these behaviours evolve across species within a phylogenetic comparative methods framework. Here we describe a new, high-throughput approach for collecting and scoring snake anti-predator displays in the field that demonstrates both low observer bias and infinite extension across any species. Then, we show our method's utility in quantitatively comparing the behaviour of 20 highly-divergent snake species from the Amazonian lowlands of Peru. We found that a simple experimental setup varying simulated predator cues was very successful in eliciting anti-predator displays across species and that high-speed videography captured a greater diversity of behavioural responses than described in the literature. We also found that although different display components evolve at different rates with complicated patterns of covariance, there is clear evidence of evolutionary convergence in anti-predator displays among distantly related elapid coral snakes and their colubrid mimics. We conclude that our approach significantly advances opportunity for future analyses of snake behaviour, kinematics, and the evolution of anti-predator signals more generally, especially macroevolutionary analyses across clades with similarly intractable behavioural diversity.
- Keyword:
- Batesian mimicry, phylogenetic comparative methods, signal evolution, aposematism, simulated predator cues, coral snakes, and Peruvian Amazon
- Citation to related publication:
- Alison R. Davis Rabosky, Talia Y. Moore, Ciara M. Sanchez-Paredes, Erin P. Westeen, Joanna G. Larson, Briana A. Sealey, Bailey A. Balinski (2020) Convergence and divergence in anti-predator displays: A novel approach to quantitative behavioural comparison in snakes. Biological Journal of the Linnean Society http://dx.doi.org/10.1093/biolinnean/blaa222
- Discipline:
- Science