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- 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
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- Creator:
- Mateling, Marian E. and Pettersen, Claire
- Description:
- This merged Global Precipitation Measurement (GPM) Core Observatory and atmospheric river dataset contains gridded Goddard Profiling (GPROF) algorithm v7 precipitation rates (Kummerow et al. 2015; Randel et al. 2020), Remote Sensing Systems (RSS) atmospheric water vapor (Meissner et al. 2012), and Mattingly et al. (2018) atmospheric rivers in the North Atlantic and North Pacific oceans. The GPROF precipitation rates and RSS atmospheric water vapor are both derived using the GPM Microwave Imager (GMI) brightness temperature observations. The atmospheric river data is derived from MERRA-2 (Modern-Era Retrospective analysis for Research and Applications Reanalysis, Version 2) integrated water vapor transport (Mattingly et al. 2018). , The data coverage starts at the beginning of the GPM data record (GPM launched in Feb 2014 and the processed data coverage starts in May 2014). Subsequent years will be added throughout the lifetime of the project. , The monthly files are compressed into year and basin: either the North Atlantic (NA) or the North Pacific (NP) (e.g., NA_2014) and zipped. The files have the basin name indicated and are by year and month (e.g., gridded_atlantic_201405.nc). The files produced are in NetCDF format ( https://www.unidata.ucar.edu/software/netcdf/) and conform to all standard NetCDF metadata conventions ( http://cfconventions.org/cf-conventions/cf-conventions.html), and Kummerow, C. D., Randel, D. L., Kulie, M., Wang, N. Y., Ferraro, R., Joseph Munchak, S., & Petkovic, V. (2015). The evolution of the Goddard profiling algorithm to a fully parametric scheme. Journal of atmospheric and oceanic technology, 32(12), 2265-2280. https://doi.org/10.1175/JTECH-D-15-0039.1 Mattingly, K. S., Mote, T. L., & Fettweis, X. (2018). Atmospheric river impacts on Greenland Ice Sheet surface mass balance. Journal of Geophysical Research: Atmospheres, 123(16), 8538-8560. https://doi.org/10.1029/2018JD028714 Meissner, T., F. J. Wentz, and D. Draper, 2012: GMI Calibration Algorithm and Analysis Theoretical Basis Document, Remote Sensing Systems, Santa Rosa, CA, report number 041912, 124 pp. Randel, D. L., Kummerow, C. D., & Ringerud, S. (2020). The Goddard Profiling (GPROF) precipitation retrieval algorithm. Satellite Precipitation Measurement: Volume 1, 141-152. https://doi.org/10.1007/978-3-030-24568-9_8
- Keyword:
- Precipitation, satellite, microwave radiometer, atmospheric water vapor, and remote sensing
- Citation to related publication:
- Mateling et al., submitted to Earth and Space Science (updated when finalized)
- Discipline:
- Science
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- Creator:
- Potter, Natalie S., McLean, Alan , Bornowski, Evan C., Hopkins, Thomas, Luo, Jingyi, Wolfe, John P., Qian, Wei, and Kopelman, Raoul
- Description:
- Research data supporting, 'Flexible Synthesis Scheme and Application of AuNP Surface-Conjugatable Meta-Iodobenzylguanidine Derivatives for Enhanced Cellular Internalization', 10.1021/acsmaterialslett.3c00781, AuNP = Au nanoparticle. In 10.1021/acsmaterialslett.3c00781, we report the synthesis and application of two metaiodobenzylguanidine (MIBG) derivatives decorated on the surface of AuNPs at high molar ratios; greatly enhanced cellular uptake is observed across neuroblastoma (NB), HeLa, and HEK cell lines. This dataset consists of synthetic NMR and mass spec data for the small molecules and their intermediates, dark-field microscopy data, inductively-coupled plasma mass spectrometry data, and raw data for characterizing the AuNPs (TEM, DLS, zeta potential).
- Keyword:
- chemistry, MIBG, nanoparticle, AuNP, synthesis, ICP-MS
- Citation to related publication:
- Flexible Synthesis Scheme and Application of AuNP Surface-Conjugatable Metaiodobenzylguanidine Derivatives for Enhanced Cellular Internalization Natalie S. Potter, Alan McLean, Evan C. Bornowski, Thomas Hopkins, Jingyi Luo, John P. Wolfe, Wei Qian, and Raoul Kopelman ACS Materials Letters Article ASAP DOI: 10.1021/acsmaterialslett.3c00781
- Discipline:
- Science
-
- Creator:
- Folz, Jeff
- Description:
- Data consists largely of UV-VIs spectra, both raw and analyzed, that were used to calibrate the relevant sensor. A more detailed description of individual files' contents can be found in the ReadMe word document.
- Discipline:
- Science
-
- Creator:
- Hou, Qian, Chatterjee, Surajit, Lund, Paul E., Suddala, Krishna C., and Walter, Nils G.
- Description:
- Bacteria live in a broad range of environmental temperatures that require adaptations of their RNA sequences to maintain function. Riboswitches are regulatory RNAs that change conformation upon binding of typical metabolite ligands to control bacterial gene expression. The paradigmatic small class-I preQ1 riboswitches from the mesophile Bacillus subtilis (Bsu) and the thermophile Thermoanaerobacter tengcongensis (Tte) adopt similar pseudoknot structures when bound to preQ1. Here, we use single-molecule detected chemical denaturation by urea to compare the thermodynamic and kinetic folding properties of the two riboswitches, and the urea-countering effects of trimethylamine N-oxide (TMAO). This data includes the experimental findings and associated analyses detailed in the research article titled "Single-molecule FRET observes opposing effects of urea and TMAO on structurally similar meso- and thermophilic riboswitch RNAs". The data consists of multiple zip files, each representing an experiment that corresponds to the key results in the publication. Each experiment includes movies, qualifying smFRET trajectories, and analysis files related to various conditions within that experimental group.
- Keyword:
- Riboswitch, Single molecule FRET, RNA folding, UV-melting, Osmolyte, Urea, and Trimethylamine N-oxide
- Citation to related publication:
- https://doi.org/10.1093/nar/gkad866
- Discipline:
- Science
-
- 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:
- 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:
- 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:
- University of Michigan Museum of Paleontology and CTEES
- Description:
- Reconstructed CT slices for tooth in bone fragment of Colognathus obscurus (University of Michigan Museum of Paleontology catalog number UMMP 7506) as a series of TIFF images. Raw projections are not included in this dataset. The reconstructed slice data from the scan are offered here as a series of unsigned 16-bit integer TIFF images. The upper left corner of the first image (*_0000.tif) is the XYZ origin.
- Keyword:
- Paleontology, Fossil, CT, Reptile, UMMP, University of Michigan Museum of Paleontology, Triassic, and bf7ead64-3fff-a3f2-6b15-d04548dae2da
- Discipline:
- Science
-
- Creator:
- Umaña, Maria, Swenson, Nathan G, and Arellano, Gabriel
- Description:
- Identifying the functional traits that enable recovery after extreme events is necessary for assessing forest persistence and functioning, yet this is a difficult task because the traits mediating the responses to disturbance may vary depending on the disturbance type and over time. This study investigates the effects of traits on tree growth –for short and longer terms– in response to two vastly different extreme climatic events, droughts, and hurricanes, in a Puerto Rican forest.
- Keyword:
- Tropical tree, relative growth rates , and Puerto Rico
- Citation to related publication:
- Umaña, M. N. In review. The interplay of drought and hurricanes on tree recovery: insights from dynamic and weak functional responses. Forthcoming and Umana, M. (2023). Functional trait data across an elevational gradient of six tree species in El Yunque National Park, Puerto Rico in 2015 [Data set], University of Michigan - Deep Blue Data. https://doi.org/10.7302/7962-4t98
- Discipline:
- Science