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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:
- Johnson, Jena E., Webb, Samuel M., Condit, Cailey B., Beukes, Nicolas J., and Fischer, Woodward W.
- Description:
- Manganese in the sedimentary record has been interpreted by many as a powerful redox proxy for paleoenvironments, and yet very little work has been done to ensure that the manganese-rich minerals in the rock record are actually recording primary signals. In the accompanying manuscript, we present an in-depth characterization of the manganese mineralogy from two correlated regions recording the Transvaal Supergroup in South Africa with markedly different alteration histories to investigate if there can be post-depositional emplacement of manganese-rich minerals. The data uploaded here are X-ray absorption spectra of (1) manganese standard minerals that were useful in our analyses and (2) minerals from an important well-characterized sample that may be useful as comparative standards in future studies.
- Keyword:
- manganese and X-ray absorption spectroscopy
- Citation to related publication:
- J.E. Johnson, S.M. Webb, C.B. Condit, N.J. Beukes, W.W. Fischer; Effects of metamorphism and metasomatism on manganese mineralogy: Examples from the Transvaal Supergroup. South African Journal of Geology doi: https://doi.org/10.25131/sajg.122.0034
- Discipline:
- Science
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- Creator:
- Hall, Ryan J. and Larson, Ronald G.
- Description:
- This is data is a large assortment of over 50 1,4-polybutadiene star-linear blends that can be used for assessing and developing predictive models. The data are presented in CSV files.
- Keyword:
- polymers, rheology, star-linear polymer blends, and shear rheology
- Citation to related publication:
- Hall, R., Desai, P. S., Kang, B.-G., Huang, Q., Lee, S., Chang, T., Venerus, D. C., Mays, J., Ntetsikas, K., Polymeropoulos, G., Hadjichristidis, N., & Larson, R. G. (2019). Assessing the Range of Validity of Current Tube Models through Analysis of a Comprehensive Set of Star–Linear 1,4-Polybutadiene Polymer Blends. Macromolecules, 52(20), 7831–7846. https://doi.org/10.1021/acs.macromol.9b00642
- Discipline:
- Science and Engineering
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- Creator:
- Linyan, Xiang and Oleg, Zikanov
- Description:
- The Liquid Metal Battery (LMB), a promising energy-storage device that contains liquid-metal interior, is studied numerically in the paper. The metal pad roll instability was modeled based on the open-source CFD software, OpenFOAM. It's based on the solver for simulations of incompressible multiphase flows multiphaseInterFoam modified to include the electromagnetic fields and account for the sharp variations of the electrical conductivity.
- Keyword:
- Liquid metal battery, Interfacial waves, Instability, and OpenFOAM
- Citation to related publication:
- Linyan Xiang (相林言) and Oleg Zikanov, “Numerical simulation of rolling pad instability in cuboid liquid metal batteries,” Physics of Fluids, vol. 31, no. 12, p. 124104, 2019, https://doi.org/10.1063/1.5123170 and Oleg Zikanov, "Shallow water modeling of rolling pad instability in liquid metal batteries." Theoretical and Computational Fluid Dynamics, 32, 325–347, 2018, https://doi.org/10.1007/s00162-018-0456-2
- Discipline:
- Science
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- Creator:
- Tronson, Natalie C and Tchessalova, Daria
- Description:
- The main goal of this research was to identify potential molecular pathways that contribute to memory dysregulation and decline that persists long after illness or inflammation. We have previously established a subchronic immune challenge model that results in memory impairments months after the inflammatory challenge. This project aimed to determine whether memory impairments were accompanied by transcriptional dysregulation in memory related brain region (the hippocampus). These data show the differential gene expression as log2fold change (and p-value) in males and females 3 months after immune challenge (Supp Tables 1 and 2); after a subsequent immune challenge (Supp Tables 3 and 4); the differential regulation of genes in males and females (Supp Table 5); genes differentially expressed in the hippocampus of males and females at baseline (Supp Table 6) and the differential regulation of those genes in males and females after immune challenge (Supp Tables 7,8).
- Keyword:
- hippocampus, lipopolysaccharide, differential gene expression, RNA sequencing, neuroimmune, sex differences, learning and memory, and inflammation
- Citation to related publication:
- Tchessalova, D., & Tronson, N. C. (2019). Enduring and sex-specific changes in hippocampal gene expression after a subchronic immune challenge. BioRxiv, 566570. https://doi.org/10.1101/566570
- Discipline:
- Science and Health Sciences
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- Creator:
- Hodgins-Davis, Andrea, Duveau, Fabien, Walker, Elizabeth, and Wittkopp, Patricia J
- Description:
- Understanding how phenotypes evolve requires disentangling the effects of mutation generating new variation from the effects of selection filtering it. Tests for selection frequently assume that mutation introduces phenotypic variation symmetrically around the population mean, yet few studies have tested this assumption by deeply sampling the distributions of mutational effects for particular traits. Here, we examine distributions of mutational effects for gene expression in the budding yeast Saccharomyces cerevisiae by measuring the effects of thousands of point mutations introduced randomly throughout the genome. We find that the distributions of mutational effects differ for the ten genes surveyed and are inconsistent with normality. For example, all ten distributions of mutational effects included more mutations with large effects than expected for normally distributed phenotypes. In addition, some genes also showed asymmetries in their distribution of mutational effects, with new mutations more likely to increase than decrease the gene’s expression or vice versa. Neutral models of regulatory evolution that take these empirically determined distributions into account suggest that neutral processes may explain more expression variation within natural populations than currently appreciated.
- Keyword:
- gene expression, evolution, mutation, mutagenesis, regulatory evolution, YFP, reporter construct, yeast, TDH1, TDH2, TDH3, GPD1, OST1, PFY1, STM1, RNR1, and RNR2
- Citation to related publication:
- Hodgins-Davis, A., Duveau, F., Walker, E. A., & Wittkopp, P. J. (2019). Empirical measures of mutational effects define neutral models of regulatory evolution in Saccharomyces cerevisiae. BioRxiv, 551804. https://doi.org/10.1101/551804
- 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:
- Bougher, S. W. (CLaSP Department, U. of Michigan), Roeten, K. J. (CLaSP Department, U. of Michigan), and Sharrar, R. (Astronomy Department, U. of Michigan)
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking daily (systematic) measurements of the densities and temperatures in the upper atmosphere of Mars between about 140 to 240 km above the surface. Wind measurement campaigns are also conducted once per month for 5-10 orbits. These densities, temperatures and winds change with time (e.g. 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. Such global dust storm period measurements can be compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. This is the first detailed comparison between direct global dust storm period measurements in the upper atmosphere of Mars and simulated MGITM fields and is important because it can help to inform us what physical processes are acting on the upper atmosphere during such large dust events. 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 key context for understanding how the atmosphere behaves as a whole system. A basic version of the M-GITM code can be found on Github as follows: https:/github.com/dpawlows/MGITM and About 4 months of Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements of densities and winds have been made by the MAVEN team during the summer of 2018 (Elrod et al., 2019). Nine reference measurement intervals during this global dust storm (1-June through 30-August 2018) are selected for detailed study (Elrod et al. 2019). The Mars conditions for these nine intervals have been used to launch corresponding M-GITM code simulations, yielding 3-D neutral density, temperature and wind fields for comparison to these NGIMS measurements. The M-GITM datacubes used to extract the density, temperature and neutral winds, along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. README files are provided for each datacube, detailing the contents of each file. A general README file is also provided that summarizes the inputs and outputs of the M-GITM code simulations for this study.
- Keyword:
- Mars, MAVEN Spacecraft, Mars Thermosphere, and Mars Global Dust Storm of 2018
- Citation to related publication:
- Elrod, M. K., S. W. Bougher, K. Roeten, R. Sharrar, J. Murphy, Structural and Compositional Changes in the Upper Atmosphere related to the PEDE-2018 Dust Event on Mars as Observed by MAVEN NGIMS, Geophys. Res. Lett., (2019). doi: 10.1029/2019GL084378. and Jain, S. K., Bougher, S. W., Deighan, J., Schneider, N. M., Gonzalez‐Galindo, F., Stewart, A. I. F., et al. ( 2020). Martian thermospheric warming associated with the Planet Encircling Dust Event of 2018. Geophysical Research Letters, 47, e2019GL085302. https://doi.org/10.1029/2019GL085302
- Discipline:
- Engineering and Science
-
- Creator:
- Liemohn, Michael W and Wooden, Paige
- Description:
- Journals sometimes focus the attention of the research community by having a special collection, sometimes an entire special issue, devoted to a single topic. A reasonable question to ask is whether the extra effort of organizing, promoting, and maintaining the special collection is worthwhile. The paper that this data set accompanies examines paper impact in the Journal of Geophysical Research Space Physics, separating the special collection papers from the non-special-collection submissions. The conclusion is that special collections are worth the extra work.
- Keyword:
- journal special collections, bibliometrics, citations, and downloads
- Citation to related publication:
- Liemohn, M. W., & Wooden, P. (2019). Editorial: Impact of special collections in JGR Space Physics. Journal of Geophysical Research Space Physics. https://doi.org/10.1002/essoar.10501036.2
- Discipline:
- Science
-
- Creator:
- Gebarski, Benjamin B. and Becker, Udo
- Description:
- Files are uploaded as crystallographic information files (.cif), the standard text file format for representing crystallographic information. These files contain the optimized molecular models for pentavalent plutonium incorporation reactions into/onto barite, anglesite, celestine, anhydrite, aragonite, and calcite host minerals.
- Keyword:
- actinide, quantum mechanics, molecular model, plutonium, incorporation, surface, radioactive, contamination, and nuclear waste
- Citation to related publication:
- Gebarski, B. B. and Becker, U. Quantum-Mechanical Determination of the Incorporation of Pentavalent Plutonium into Carbonate and Sulfate Minerals. (2019) Geochimica et Cosmochimica Acta. https://doi.org/10.1016/j.gca.2019.10.015
- Discipline:
- Science