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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:
- 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
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- 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
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- 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
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- Creator:
- Ludlow, Andrew and Kim, Jeongjin
- Description:
- Part of the regulation of telomerase activity includes the alternative splicing (AS) of the catalytic subunit telomerase reverse transcriptase (TERT). Although a therapeutic window for telomerase/TERT inhibition exists between cancer cells and somatic cells, stem cells express TERT and rely on telomerase activity for physiological replacement of cells. Therefore, identifying differences in TERT regulation between stem cells and cancer cells is essential for developing telomerase inhibition-based cancer therapies that reduce damage to stem cells. In this study, we measured TERT splice variant expression and telomerase activity in induced pluripotent stem cells (iPSCs), neural progenitor cells (NPCs), and non-small cell lung cancer cells (NSCLC, Calu-6 cells). We observed that a NOVA1-PTBP1-PTBP2 axis regulates TERT alternative splicing (AS) in iPSCs and their differentiation into NPCs. We also found that splice-switching of TERT, which regulates telomerase activity, is induced by different cell densities in stem cells but not cancer cells. Lastly, we identified cell type-specific splicing factors that regulate TERT AS. Overall, our findings represent an important step forward in understanding the regulation of TERT AS in stem cells and cancer cells. These data and subsequent studies may reveal a splicing factor(s) or their binding site(s) that could be targeted with small molecule drugs or antisense oligonucleotides, respectively, to reduce telomerase activity in cancer cells and promote durable cancer remissions.
- Keyword:
- Telomere, telomerase, TERT, alternative RNA splicing
- Citation to related publication:
- Dynamics of TERT Regulation via Alternative Splicing in Stem Cells and Cancer Cells. Accepted in Plos One
- Discipline:
- Science
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- Creator:
- Ye, Zhengwei and Mi, Zetian
- Description:
- Generation of C2+ compounds using sunlight, carbon dioxide, and water provides a promising path for carbon neutrality. The exploration of a catalyst to break the bottleneck of C-C coupling, for constructing a rational artificial photosynthesis integrated device, is at the core. Herein, based on operando spectroscopy measurements, theoretical calculations, and feedstock experiments, it is discovered that gold, in conjunction with iridium, can catalyze the reduction of CO2, achieving C-C coupling by insertion of CO2 into -CH3. Owing to a combination of optoelectronic and catalytic properties, the assembly of AuIr with InGaN nanowires on silicon (AuIr@InGaN NWs/Si) enables the achievement of a C2H6 activity of 58.8 mmol‧g-1‧h-1 with a turnover number of 54,595 over 60 hours. A light-to-fuels efficiency of ~0.59% for solar fuels production from CO2 and H2O is achieved without any other energy inputs. This work provides a carbon-negative path for producing higher order C compounds.
- Keyword:
- Carbon dioxide reduction and Photocatalysis
- Discipline:
- Science
-
- Creator:
- Martin, Tara L, Young, LR, Goldsteen, D, Nunamaker, EA, Reynolds, P, Thompson-Iritani, S, Thurston, SE, and LaFollette, MR
- Description:
- This dataset contains the results of a survey of mouse handling methods by personnel working with laboratory mice. The survey included questions about preferred handling methods, barriers to use of refined handling methods, and a knowledge quiz about refined mouse handling. Data was collected via Qualtrics survey as described in the methodology section. This dataset is associated with the following publication, accepted by PLOS One: PONE-D-23-01633R1 Title: Using refined methods to pick up mice: A survey benchmarking prevalence & beliefs about tunnel and cup handling Authors: Lauren Young, Donna Goldsteen, Elizabeth A. Nunamaker, Mark J. Prescott, Penny Reynolds, Sally Thompson-Iritani, Sarah E. Thurston, Tara L. Martin, Megan R. LaFollette
- Keyword:
- Mouse, Refined Handling, Tunnel Handling, Cup Handling, Laboratory Animal, and Animal Care
- Citation to related publication:
- Young LR, Goldsteen D, Nunamaker EA, Prescott MJ, Reynolds P, Thompson-Iritani S, Thurston SE, Martin TL, LaFollette MR. Using refined methods to pick up mice: A survey benchmarking prevalence & beliefs about tunnel and cup handling. PLOS ONE. 2023. In Press.
- Discipline:
- Science
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- Creator:
- Dewey, Ryan M, Livi, Stefano, Lepri, Susan T, Raines, Jim M, Ploof, Keeling, and The HIS Science Team
- Description:
- The data contained within the archive are for analysis and replication of Figure 2 in Livi et al. (2023), First Results from the Solar Orbiter Heavy Ion Sensor, Astronomy & Astrophysics. The readme.txt file contains more details on the contents of the archive and its files. Livi et al. (2023) reports the first solar wind composition measurements collected from the Heavy Ion Sensor (HIS) on the Solar Orbiter spacecraft. The period of study spans January-June 2022 during with the spacecraft completed nearly a full orbit about the Sun, from 0.3 AU to 1.0 AU. The solar wind composition within this publication are the first within the inner heliosphere. This paper describes the data and its processing from raw measurements (e.g., the data contained within this archive) to derived composition data products, and examines these composition data products about an interplanetary shock and interplanetary coronal mass ejection. Finally, these composition data are examined statistically and compared to historical data sets.
- Keyword:
- Solar Orbiter, Solar wind, Heavy ions, and Heavy Ion Sensor
- Citation to related publication:
- Livi, S., et al. (2023), First Results from the Solar Orbiter Heavy Ion Sensor, Astronomy & Astrophysics. https://doi.org/10.1051/0004-6361/202346304 and Owen, C., et al. (2020), The Solar Orbiter Solar Wind Analyser (SWA) suite, Astronomy & Astrophysics, 642. https://doi.org/10.1051/0004-6361/201937259
- Discipline:
- Science
-
- Creator:
- Thompson, Ellen P. and Ellis, Brian R.
- Description:
- Accurate prediction of physical alterations in carbonate reservoirs under dissolution is critical for development of subsurface energy technologies. The impact of mineral dissolution on flow characteristics depends on the connectivity and tortuosity of the pore network. Persistent homology is a tool from algebraic topology that describes the size and connectivity of topological features. When applied to 3D X-ray computed tomography (XCT) imagery of rock cores, it provides a novel metric of pore network heterogeneity. Prior works have demonstrated the efficacy of persistent homology in predicting flow properties in numerical simulations of flow through porous media. Its ability to combine size, spatial distribution, and connectivity information make it a promising tool for understanding reactive transport in complex pore networks, yet limited work has been done to apply persistence analysis to experimental studies on natural rocks. In this study, three limestone cores were imaged by XCT before and after acid-driven dissolution flow through experiments. Each XCT scan was analyzed using persistent homology. In all three rocks, permeability increase was driven by the growth of large, connected pore bodies. The two most homogenous samples saw an increased effect nearer to the flow inlet, suggesting emerging preferential flow paths as the reaction front progresses. The most heterogeneous sample showed an increase in along-core homogeneity during reaction. Variability of persistence showed moderate positive correlation with pore body size increase. Persistence heterogeneity analysis could be used to anticipate where greatest pore size evolution may occur in a reservoir targeted for subsurface development, improving confidence in project viability.
- Keyword:
- Carbonate dissolution, X-ray computed tomography, Porous media, Topology, and Persistent homology
- Citation to related publication:
- Thompson, E.P.; Ellis, B.R. (2023) Persistent Homology as a Heterogeneity Metric for Predicting Pore Size Change in Dissolving Carbonates. In Review.
- Discipline:
- Science and Engineering