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- Creator:
- Engebretson, Mark J.
- Description:
- Large geomagnetic disturbances (GMDs, also denoted as MPEs - magnetic perturbation events) have sufficient amplitude to cause geomagnetically induced currents (GICs) that can damage technical infrastructure. In this study we present occurrence statistics for GMD / MPE events with derivatives ≥ 6 nT/s and ≥ 20 nT/s from five stations in the MACCS and AUTUMNX magnetometer arrays in Arctic Canada at magnetic latitudes ranging from 65° to 75°. Earlier studies using data from these arrays (Engebretson et al., 2019a,b, 2021a,b) covered only two years (2015 and 2017) and focused on latitude- and local time-dependent occurrence patterns and short-term dependencies on solar wind/IMF parameters and magnetospheric activity indices. This study presents all available data from these stations from 2011 through 2022 to analyze variations of GMD activity over a full solar cycle. Intense GMD activity did not closely follow the sunspot cycle, but instead was lowest during its rising phase and maximum (2011-2014), was highest during the early declining phase (2015-2017), and reached a subsequent minimum early in the following sunspot cycle (2020). GMDs with amplitude >20 nT/s followed the same yearly pattern but peaked even more strongly during 2015-2017. Most of these GMDs were associated with high-speed solar wind streams (Vsw > 600 km/s), but not with strongly negative values of the SYM/H index. The majority of these GMDs, irrespective of the Vsw value, were accompanied within 10 min (and most often less) by other events with amplitude ≥ 6 nT/s and showed a mostly poleward progression. These results show that large amplitude but spatially localized nighttime GMDs are primarily associated with high-speed stream geomagnetic drivers during the declining phase of the solar cycle. This indicates that large GIC hazard conditions can occur for a variety of solar wind drivers and geomagnetic conditions and not only for fast-coronal mass ejection driven storms.
- Keyword:
- geomagnetic disturbance events, geomagnetically induced currents
- Citation to related publication:
- Engebretson, M. J., Steinmetz, Yang, L., Pilipenko, V. A., Moldwin, M. B., McCuen, B. A., Connors, M. G., Weygand, J. M., Waters, C. L., Lyons, L. R., Nishimura, Y., Russell, C. T. (2023) Solar Cycle Dependence of Very Large Nighttime Geomagnetic Disturbances (GMDs) Observed in Eastern Arctic Canada. Journal of Geophysical Research – Space Physics
- Discipline:
- Science
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- Creator:
- Lumeng, Julie C
- Description:
- Healthy full-term infants were enrolled in a longitudinal study designed to examine the development of infant eating behavior. Infant weight and length was measured, mothers completed questionnaires regarding infant eating behaviors, and infant sucking behavior was quantified using the NFANT device during a typical feeding. The predictive value of the NFANT-generated sucking metrics for infant weight gain was evaluated.
- Keyword:
- infant, eating, weight gain, and sucking
- Citation to related publication:
- Feldman, Keith, Katharine Asta, Ashley N. Gearhardt, Julie M. Sturza, Danielle Appugliese, Alison L. Miller, Katherine Rosenblum, Kai Ling Kong, Amanda K. Crandall, and Julie C. Lumeng. "Characterization of a Vigorous sucking style in early infancy and its predictive value for weight gain and eating behaviors at 12 months." Appetite (2023): 106525.
- Discipline:
- Health Sciences
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- Creator:
- Kort, Eric A., Plant, Genevieve, Brandt, Adam R., Chen, Yuanlei, Fordice, Graham, Gorchov Negron, Alan M., Schwietzke, Stefan, Smith, Mackenzie, and Zavala-Araiza, Daniel
- Description:
- As part of the Flaring & Fossil Fuels: Uncovering Emissions & Losses (F3UEL) project, the aircraft measurement platform sampled downwind of flares in the Permian and Eagle Ford regions of Texas (2020) and the Bakken in North Dakota (2021). Estimates of methane destruction removal efficiency are calculated for each airborne intercept of a flare combustion plume based on the observed enhancements of carbon dioxide and methane, along with assumptions about the flare gas composition. Locations provided are the GPS coordinates for the aircraft sampling, not of the upwind flare infrastructure on the ground. Attempts to link the airborne sampling locations to ground infrastructure using the provided wind information (measured at the aircraft), should take care to account for complexities of transport in the atmosphere.
- Keyword:
- Natural Gas Flaring, Methane, and Oil & Gas
- Citation to related publication:
- Plant, G., Kort, E. A., Brandt, A. R., Chen, Y., Fordice, G., Gorchov Negron, A. M., Schwietzke, S., Smith, M., & Zavala-Araiza, D. (2022). Inefficient and unlit natural gas flares both emit large quantities of methane. Science, 377(6614), 1566–1571. https://doi.org/10.1126/science.abq0385, Kort, E. A., Plant, G., Smith, M. L., Brandt, A. R., Chen, Y., Gorchov Negron, A. M., Schwietzke, S., Zavala-Araiza, D. (2022). Aircraft Data (2020) for Flaring & Fossil Fuels: Uncovering Emissions & Losses (F3UEL), University of Michigan - Deep Blue Data. https://doi.org/10.7302/1xjm-3v49, and Kort, E. A., Plant, G., Brandt, A. R., Chen, Y., Gorchov Negron, A. M., Schwietzke, S., Smith, M. L., Zavala-Araiza, D. (2022). Aircraft Data (2021) for Flaring & Fossil Fuels: Uncovering Emissions & Losses (F3UEL), University of Michigan - Deep Blue Data. https://doi.org/10.7302/6tgq-e116
- Discipline:
- Science
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- Creator:
- Bueno-Junior, Lezio S., Ruckstuhl, Maxwell S., Lim, Miranda M., and Watson, Brendon O.
- Description:
- Rapid eye movement sleep (REM) is believed to have a binary temporal structure with “phasic” and “tonic" microstates, characterized by motoric activity versus quiescence, respectively. However, we observed in mice that the frequency of theta activity (a marker of rodent REM) fluctuates in a non-binary fashion, with the extremes of that fluctuation correlating with phasic-type and tonic-type facial motricity. Thus, phasic and tonic REM may instead represent ends of a continuum. These cycles of brain physiology and facial movement occurred at 0.01-0.06 Hz, or infraslow frequencies, and affected cross-frequency coupling and neuronal activity in the neocortex, suggesting network functional impact. We then analyzed human data and observed that humans also demonstrate non-binary phasic/tonic microstates, with continuous 0.01-0.04 Hz respiratory rate cycles matching the incidence of eye movements. These fundamental properties of REM can yield new insights into our understanding of sleep health.
- Keyword:
- REM sleep, Infraslow fluctuations, Facial movements, Theta oscillations, and Respiration rate
- Citation to related publication:
- L. S. Bueno-Junior, M. S. Ruckstuhl, M. M. Lim, B. O. Watson, The temporal structure of REM sleep shows minute-scale fluctuations across brain and body in mice and humans. Proc. Natl. Acad. Sci. U. S. A. In press (2023).
- Discipline:
- Science
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- Creator:
- Sun, Hu
- Description:
- Complete Global Total Electron Content Database based on the VISTA Algorithm
- Keyword:
- Total Electron Content, Matrix Completion, VISTA, Spherical Harmonics, and Spatial-Temporal Smoothing
- Discipline:
- Engineering
2Works -
Projekti Arkeologjik i Shkodrës (PASH)
User Collection
- Creator:
- Galaty, Michael
- Description:
- The data presented here were collected in the course of archaeological survey and excavation in the region of Shkodër in northern Albania, carried out between 2010 and 2014, with a follow-up visit in 2016. The Projekti Arkeologjik i Shkodrës (PASH) was co-directed by Michael L. Galaty (University of Michigan) and Lorenc Bejko (University of Tirana) and was sponsored by the United States National Science Foundation (NSF BCS1220016), The University of Tirana, Millsaps College, Mississippi State University, and the University of Michigan. The data presented here accompany a two-volume research report, published by the University of Michigan Museum of Anthropological Archaeology Press (Galaty and Bejko 2023) - Volume 1 ( https://doi.org/10.3998/mpub.12201317) and Volume 2 ( https://doi.org/10.3998/mpub.12208577)., The county (Alb. qarqe) of Shkodër is located in northern Albania. It is bordered to the south by the Adriatic Sea and to the northwest by the country of Montenegro. The counties of Lezhë and Kukës are situated to the south and east, respectively. Shkodër Lake is situated along the border with Montenegro. It is the largest freshwater lake in the Balkans. The city of Shkodër is the fifth largest in Albania. It was founded in the Bronze Age and became a Roman colony in 168 BC, following the Illyrian Wars. Several major rivers intersect at Shkodër, including the Buna, which exits Shkodër Lake, the Drin, and the Kir. The latter two rivers flow from the Bjeshkët e Nemuna, the Albanian Alps, and provide access across the mountains, to the Balkan interior, including metal-rich Kosovo. Several very important ancient sites are located to the south of Shkodër, close to the Adriatic coast: Lezhë (ancient Lissus), Apollonia, and Durrës (ancient Epidamnus, Dyrrachium under the Romans). The latter two cities were Greek colonies, founded during the Archaic period. All three became Roman colonies., and PASH was designed to investigate shifts, through time, in Shkodër towards increased social stratification and hierarchy. These shifts commenced during prehistory and are marked by two dramatic changes in the regional landscape: new settlement in defensible “hillforts” and burial in rock and earth mounds. We wondered what factors – environment, settlement, status, conflict, subsistence, trade, migration – might have allowed or encouraged these changes.
- Keyword:
- archaeology
- Discipline:
- Science and Humanities
5Sub-collections1Works -
Data for Macroscopic Transition Metal Dichalcogenides Monolayers with Uniformly High Optical Quality
- Creator:
- Li, Qiuyang, Alfrey, Adam, Hu, Jiaqi, Lydick, Nathanial, Paik, Eunice, Liu, Bin, Sun, Haiping, Lu, Yang, Wang, Ruoyu, Forrest, Stephen, and Deng, Hui
- Description:
- This dataset contains raw and source data for all figures generated in the manuscript "Macroscopic Transition Metal Dichalcogenides Monolayers with Uniformly High Optical Quality" The raw data files include '.spe' data, which are spectral data collected by LightField Sofware, and '.dset' and '.vms' files, which are X-ray photoelectron spectroscopy (XPS) data and require CasaXPS to access. The source data files include the processed data that can be directly used for generating the corresponding figures in the manuscript.
- Keyword:
- 2D materials, Exciton-polaritons, and Photonics
- Discipline:
- Science
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- Creator:
- Galaty, Michael
- Description:
- These data relate to PASH’s excavations at tumuli 099. This record contains scanned documents (excavation forms, log book, notebook, drawings), 211 .jpg images in 19 folders (labeled by date, one with candids), as well as a photolog and C14 AMS radiocarbon date data. and Chapter linked to: Eight
- Keyword:
- archaeology
- Discipline:
- Humanities and Science
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- Creator:
- Galaty, Michael
- Description:
- These data relate to PASH’s excavations at tumuli 088. This record contains scanned documents (excavation forms, a notebook and drawings), 152 .jpg photos in 17 folders (labeled by date) and a photolog. and Chapter linked to: Eight
- Keyword:
- archaeology
- Discipline:
- Science and Humanities
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- Creator:
- Galaty, Michael
- Description:
- These data relate to PASH’s excavations at tumuli 085. This record contains scanned documents (excavation forms, drawings, and notes--though these last are difficult to read), 34 .jpg excavation photos (no photolog), and time slice images of GPR data as a .pdf (raw geophysical data for this survey are not available). and Chapter linked to: Eight
- Keyword:
- archaeology
- Discipline:
- Humanities and Science