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- Creator:
- Kort, Eric A., Plant, Genevieve, Brandt, Adam R., Chen, Yuanlei, Gorchov Negron, Alan M., and Smith, Mackenzie L.
- Description:
- As part of the Flaring & Fossil Fuels: Uncovering Emissions & Losses (F3UEL) project, in 2022 the aircraft measurement platform sampled offshore oil & gas facilities in the US Gulf of Mexico to quantify facility-level emissions using the approach detailed in Conley et al. (2017). Vertical profiles were conducted on each flight to capture the vertical structure and mixing depths of the atmosphere. The data file contains all merged flight data from each flight day. Reference: Conley, S., Faloona, I., Mehrotra, S., Suard, M., Lenschow, D. H., Sweeney, C., Herndon, S., Schwietzke, S., Pétron, G., Pifer, J., Kort, E. A., and Schnell, R.: Application of Gauss’s theorem to quantify localized surface emissions from airborne measurements of wind and trace gases, Atmos. Meas. Tech., 10, 3345 – 3358, 2017.
- Keyword:
- Offshore Oil & Gas, Methane, Nitrogen Oxides, and Gulf of Mexico
- Discipline:
- Science
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- Creator:
- Ray, Sujay
- Description:
- Single molecule data and analysis code for Figure4 in the paper titled: "A rhythmically pulsing leaf-spring DNA-origami nanoengine that drives a passive follower". Follow the readme file for deiails.
- Discipline:
- Science
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- Creator:
- Ponder, Brandon M., Ridley, Aaron J., Goel, Ankit, and Bernstein, Dennis S.
- Description:
- This research was completed to statistically validate that a data-model refinement technique could integrate real measurements to remove bias from physics-based models via changing the forcing parameters such as the thermal conductivity coefficients.
- Keyword:
- Thermosphere, GITM, CHAMP, GRACE, MSIS, Upper Atmosphere Modeling, and Data Assimilation
- Citation to related publication:
- Ponder, B. M., Ridley, A. J., Goel, A., & Bernstein, D. S. (2023). Improving forecasting ability of GITM using data-driven model refinement. Space Weather, 21, e2022SW003290. https://doi.org/10.1029/2022SW003290
- Discipline:
- Engineering and Science
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- Creator:
- Ansong, Joseph K. and Arbic, Brian K.
- Description:
- This is the model and observational data referenced in our manuscript entitled “surface and sub-subsurface internal gravity wave kinetic energy spectra from global ocean models and observations.” The model data for the 7 regions from the two global simulations (HYCOM and MITgcm) can be found here.
- Keyword:
- vertical wavenumber spectra of internal waves, surface kinetic energy spectra, and ratio of high versus low-frequency surface kinetic energy
- Citation to related publication:
- Ansong, J.K., et al., "forthcoming", Surface and sub-subsurface internal gravity wave kinetic energy spectra in global ocean models and observations
- Discipline:
- Science
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- Creator:
- McCuen, Brett A.
- Description:
- We present a comprehensive statistical analysis of high-frequency transient-large-amplitude (TLA) magnetic perturbation events that occurred at 12 high-latitude ground magnetometer stations throughout solar cycle 24 from 2009 to 2019. TLA signatures are defined as one or more second-timescale dB/dt interval with magnitude ≥ 6 nT/s within an hour event window. This study characterizes high-frequency TLA events based on their spatial and temporal behavior as well as relation to auroral substorms, geomagnetic storm phases and nighttime geomagnetic disturbance events events (GMD). We show that TLA events occur primarily at nighttime and solely in the high-latitude region above 60 degrees geomagnetic latitude. The largest TLA events occurred more often in the declining phase of the solar cycle when solar wind velocity was higher and ring current activity was lower, suggesting association to high-speed flows caused by coronal holes and subsequent corotating interaction regions reaching Earth. TLA perturbations often occurred preceding or within the most extreme nighttime geomagnetic disturbance (GMD) events with 5-10 minute timescales, but the TLA intervals were often even more localized than the ~300 km effective radius of GMDs: occurring at only some of the stations at which GMDs occurred. We show that TLA-related GMD events can result from dipolarization fronts in the magnetotail and fast flows toward Earth and are closely temporally associated to poleward boundary intensifications (PBI) and auroral streamers. The highly localized behavior and connection to the most extreme GMD events suggests that TLA intervals are a ground manifestation of the features within rapid and complex ionospheric structures that can drive GICs.
- Keyword:
- geomagnetic field, high frequency, space weather, transient-large-amplitude, TLA, high frequency dB/dt, dB/dt search algorithm
- Citation to related publication:
- McCuen, B. A., Moldwin, M. B., Engebretson, M. J., Weygand, J. G., Nishimura, Y. (2023). A Statistical Analysis of High-frequency Transient-Large-Amplitude Geomagnetic Disturbance. [To be submitted to] Journal of Geophysical Research: Space Physics
- Discipline:
- Science
-
- Creator:
- Wittkopp, Patricia J and Massey, Jonathan H
- Description:
- Data provided in this record were collected in the course of studying the genetic basis of differences in wing pigmentation and wing display between Drosophila elegans and Drosophila gunungcola.
- Citation to related publication:
- Massey, J. H., Rice, G. R., Firdaus, A. S., Chen, C.-Y., Yeh, S.-D., Stern, D. L., & Wittkopp, P. J. (2020). Co-evolving wing spots and mating displays are genetically separable traits in Drosophila. Evolution, 74(6), 1098–1111. https://doi.org/10.1111/evo.13990
- Discipline:
- Science
-
- Creator:
- Moore, Talia Y., Danforth, Shannon M., Larson, Joanna G., and Davis Rabosky, Alison R.
- Description:
- Warning signals in chemically defended organisms are critical components of predator-prey interactions, often requiring multiple coordinated display components for a signal to be effective. When threatened by a predator, venomous coral snakes (genus Micrurus) display a vigorous, non-locomotory thrashing behaviour that has been only qualitatively described. Given the high-contrast and often colourful banding patterns of these snakes, this thrashing display is hypothesized to be a key component of a complex aposematic signal under strong stabilizing selection across species in a mimicry system. By experimentally testing snake response across simulated predator cues, we analysed variation in the presence and expression of a thrashing display across five species of South American coral snakes. Although the major features of the thrash display were conserved across species, we found significant variation in the propensity to perform a display at all, the duration of thrashing, and the curvature of snake bodies that was mediated by predator cue type, snake body size, and species identity. We also found an interaction between curve magnitude and body location that clearly shows which parts of the display vary most across individuals and species. Our results suggest that contrary to the assumption in the literature that all species and individuals perform the same display, a high degree of variation persists in thrashing behaviour exhibited by Micrurus coral snakes despite presumably strong selection to converge on a common signal. This quantitative behavioural characterization presents a new framework for analysing the non-locomotory motions displayed by snakes in a broader ecological context, especially for signalling systems with complex interaction across multiple modalities.
- Keyword:
- aposematism, biomechanics, coral snake mimicry, curvature, Elapidae, non-locomotory motion, Peruvian Amazon, and snake behaviour
- Citation to related publication:
- Moore, T. Y., Danforth, S. M., Larson, J. G., & Davis Rabosky, A. R. (2020). A Quantitative Analysis of Micrurus Coral Snakes Reveals Unexpected Variation in Stereotyped Anti-Predator Displays Within a Mimicry System. Integrative Organismal Biology, 2(1). https://doi.org/10.1093/iob/obaa006
- Discipline:
- Science
-
- Creator:
- Ridley, Aaron and Cnossen, Ingrid
- Description:
- These are modeling results of the thermospheric and ionospheric response to the solar eclipse of August 21, 2017. The results are discussed in a research paper published in the Journal of Geophysical Research (doi: 10.1029/2018JA026402) .
- Citation to related publication:
- Cnossen, I., Ridley, A. J., Goncharenko, L. P., and Harding, B. J.. ( 2019), The response of the ionosphere‐thermosphere system to the August 21, 2017 solar eclipse. J. Geophys. Res. Space Physics, 124. https://doi.org/10.1029/2018JA026402
- Discipline:
- Science
-
- Creator:
- dos Santos, Thiago, Steiner, Allison, Keppel-Aleks, Gretchen, and De Roo, Roger
- Description:
- Model simulations were conducted to investigate the role of soil moisture on the terrestrial carbon and water cycles. The data are composed of NetCDF files generated by the simulations that contain the data variables analyzed in the paper. and CLM5 Documentation - http://www.cesm.ucar.edu/models/cesm2/land/.
- Keyword:
- Soil moisture, Community Land Model 5, Latent heat, GPP, Gross primary productivity, and Fluxnet
- Citation to related publication:
- Santos, T. dos, Keppel-Aleks, G., Roo, R. D., & Steiner, A. L. (2021). Can Land Surface Models Capture the Observed Soil Moisture Control of Water and Carbon Fluxes in Temperate-To-Boreal Forests? Journal of Geophysical Research: Biogeosciences, 126(4), e2020JG005999. https://doi.org/10.1029/2020JG005999
- Discipline:
- Science
-
- Creator:
- Ruas, Terry, Ferreira, Charles H. P., Grosky, William, França, Fabrício O., and Medeiros, Débora M. R,
- Description:
- The relationship between words in a sentence often tell us more about the underlying semantic content of a document than its actual words, individually. Recent publications in the natural language processing arena, more specifically using word embeddings, try to incorporate semantic aspects into their word vector representation by considering the context of words and how they are distributed in a document collection. In this work, we propose two novel algorithms, called Flexible Lexical Chain II and Fixed Lexical Chain II that combine the semantic relations derived from lexical chains, prior knowledge from lexical databases, and the robustness of the distributional hypothesis in word embeddings into a single decoupled system. In short, our approach has three main contributions: (i) unsupervised techniques that fully integrate word embeddings and lexical chains; (ii) a more solid semantic representation that considers the latent relation between words in a document; and (iii) lightweight word embeddings models that can be extended to any natural language task. Knowledge-based systems that use natural language text can benefit from our approach to mitigate ambiguous semantic representations provided by traditional statistical approaches. The proposed techniques are tested against seven word embeddings algorithms using five different machine learning classifiers over six scenarios in the document classification task. Our results show that the integration between lexical chains and word embeddings representations sustain state-of-the-art results, even against more complex systems. Github: https://github.com/truas/LexicalChain_Builder
- Keyword:
- document classification, lexical chains, word embeddings, synset embeddings, chain2vec, and natural language processing
- Citation to related publication:
- Terry Ruas, Charles Henrique Porto Ferreira, William Grosky, Fabrício Olivetti de França, Débora Maria Rossi de Medeiros, "Enhanced word embeddings using multi-semantic representation through lexical chains", Information Sciences, 2020, https://doi.org/10.1016/j.ins.2020.04.048
- Discipline:
- Other, Science, and Engineering