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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:
- Crisp, Dakota N., Saggio, Maria L., Scott, Jared, Stacey, William C., Nakatani, Mitsuyoshi, Gliske, Stephen V., and Lin, Jack
- Description:
- This data and scripts are meant to test and show seizure differentiation based on bifurcation theory. A zip file is included which contains real and simulated seizure waveforms, Matlab scripts, and metadata. The matlab scripts allow for visual review validation and objective feature analysis. The file “README.txt” provides more detail about each individual file within the zip file. and Data citation: Crisp, D.N., Saggio, M.L., Scott, J., Stacey, W.C., Nakatani, M., Gliske, S.F., Lin, J. (2019). Epidynamics: Navigating the map of seizure dynamics - Code & Data [Data set]. University of Michigan Deep Blue Data Repository. https://doi.org/10.7302/ejhy-5h41
- Keyword:
- Bifurcation, Epilepsy, Seizure, and Divergence
- Citation to related publication:
- Saggio, M.L., Crisp, D., Scott, J., Karoly, P.J., Kuhlmann, L., Nakatani, M., Murai, T., Dümpelmann, M., Schulze-Bonhage, A., Ikeda, A., Cook, M., Gliske, S.V., Lin, J., Bernard, C., Jirsa, V., Stacey, W., 2020. In pre-print. Epidynamics characterize and navigate the map of seizure dynamics. bioRxiv 2020.02.08.940072. https://doi.org/10.1101/2020.02.08.940072
- Discipline:
- Engineering, Science, and Health Sciences
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- Creator:
- Ding, J, Moore, TY, and Gan, Z
- Description:
- Jerboas (Jaculus jaculus) are bipedal hopping rodents that frequently transition between gaits (running, hopping, and skipping) throughout their entire speed range. It has been hypothesized that these non-cursorial bipedal gait transitions are likely to enhance their maneuverability and predator evasion ability. However, it is difficult to use the underlying dynamics of these locomotion patterns to predict gait transitions due to the large number of degrees of freedom expressed by the animals. To this end, we used empirical jerboa kinematics and dynamics to develop a unified Spring Loaded Inverted Pendulum model with defined passive swing leg motions. The simulated trajectories from the model precisely matched the experimental data. Jerboas were observed to apply different neutral swing leg angles during locomotion. By investigating the gait structure of the model with coupled and uncoupled neutral swing leg, we found two set of mechanism may explain the frequent gait transitions of jerboas.
- Keyword:
- jerboa, legged locomotion, gait transition, Legged Robots, Dynamics, Bipedal locomotion, and Non-cursorial locomotion
- Citation to related publication:
- Ding, Moore, Gan (submitted) A template model explains jerboa gait transitions across a broad range of speeds. Frontiers in Bioengineering And Biotechnology
- Discipline:
- Science and Engineering
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- Creator:
- Jones, Monica L.H.
- Description:
- This study evaluated the performance of a video-based intervention for improving the belt fit obtained by drivers. Previous laboratory studies have demonstrated that some drivers position their seat belts suboptimally. Specifically, the lap portion of the belt may be higher and farther forward relative to the pelvis than best practice, and the shoulder portion of the belt may be outboard or inboard of mid-shoulder. A video was developed to present the most important aspects of belt fit best practices, with emphasis on the lap belt. The video demonstrated how a seat belt should be routed with respect to an individual’s anatomy to ensure a proper fit. The three key belt fit concepts conveyed in the video were: 1) Lap belt low on hips, touching the thighs. 2) Shoulder belt crossing middle of collarbone. 3) Belt snug, as close to bones as possible. Additional context about the ability to achieve to good belt fit, such as opening a heavy coat or adjusting the height adjusters on the B-pillar behind the windows, were also presented.
- Keyword:
- Safety, Seatbelt Fit, Intervention, and Evaluation
- Citation to related publication:
- Jones, M.L.H., Ebert, S.M., Buckley, L., Park, J., and Reed, M.P. (2016). Evaluating an Intervention to Improve Belt Fit for Drivers. Technical Report UMTRI 2016-12. University of Michigan Transportation Research Institute, Ann Arbor, MI. , Reed, M.P., Ebert-Hamilton, S.M. and Rupp, J.D. (2012). Effects of obesity on seat belt fit. Traffic Injury Prevention, 13(4):364-372. https://doi.org/10.1080/15389588.2012.659363, Reed, M.P., Ebert, S.M. and Hallman, J.J. (2013). Effects of driver characteristics on seat belt fit. Stapp Car Crash Journal, 57:43-57. https://pubmed.ncbi.nlm.nih.gov/24435726/, and Jones, M.L.H., Ebert, S.M., and Reed, M.P. (2015). Effects of High Levels of Obesity on Driver Seat Belt Fit. Advancing Transportation Leadership and Safety Technical Report ATLAS-2015-016. University of Michigan Transportation Research Institute, Ann Arbor, MI. https://trid.trb.org/view/1427384 http://www.atlas-center.org/wp-content/uploads/2015/08/ATLAS-Final-Report-ATLAS-2016-15.pdf
- Discipline:
- Engineering
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- Creator:
- Piette, John and Abbott, Patricia A
- Description:
- Contained within is a subset of the larger dataset collected in La Paz, Bolivia in 2014. This data contains the analytic dataset (cross-sectional/descriptive) that includs the PACIC, Morisky, PHQ8, AUDIT, and a subset of socidemographic characteristics for NCD patients in La Paz.
- Keyword:
- Global Health, Bolivia, and Non-communicable disease
- Discipline:
- Health Sciences
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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 capacity for regulation of energy intake was evaluated by comparing intake between two days: one with feedings given on demand and one with feedings offered hourly. The infant's ability to downregulate intake in response to more frequent feedings was calculated.
- Keyword:
- infant, eating, weight gain, feeding, and energy regulation
- Citation to related publication:
- Reynolds, L. A., McCaffery, H., Appugliese, D., Kaciroti, N. A., Miller, A. L., Rosenblum, K. L., ... & Lumeng, J. C. (2023). Capacity for Regulation of Energy Intake in Infancy. JAMA pediatrics, 177(6), 590-598.
- Discipline:
- Health Sciences
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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:
- 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 infants were weighed and length measured at ages 1, 2, 4, 6 and 10 months. Trajectories of eating behaviors were identified using latent class growth modeling and bivariate analyses examined associations of infant eating behavior trajectory membership with infant and maternal characteristics. Cross-lagged analyses examined associations between BEBQ subscales and infant weight-for-length z-score.
- Keyword:
- infant, eating, weight gain, and feeding
- Citation to related publication:
- Harlan McCaffery, Julie Zaituna, Sophie Busch, Niko Kaciroti, Alison L. Miller, Julie C. Lumeng, Katherine L. Rosenblum, Ashley Gearhardt, Megan H. Pesch, Developmental trajectories of eating behaviors and cross-lagged associations with weight across infancy, Appetite, 2023, 106978
- Discipline:
- Health Sciences
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- Creator:
- Lumeng, Julie C
- Description:
- Infant eating behavior is likely driven not only by hunger and satiety reflective of caloric need, but also by the reward value of food. The reward value of food can be understood in terms of wanting, liking, and salience. Little is understood about infant response to the reward value of food, or its predictors, particularly prenatally. This project sought to understand whether prenatal factors during pregnancy predict infant reward response to food, as measured by questionnaires in early infancy.
- Keyword:
- wanting, liking, salience, infancy, eating, growth, and prenatal
- Discipline:
- Health Sciences
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- Creator:
- Dulka, Eden A
- Description:
- This data is a subset of that originally produced as part of an effort to characterize GnRH neuron activity during prepubertal development in control and PNA mice and investigate the potential influences of sex and PNA treatment on this process (1). It was later used in (2) to further investigate the firing patterns of GnRH neurons in these categories of mice and determine how these patterns might differ based on age and treatment condition. The data files can be opened and examined using Wavemetric's Igor Pro software. Code used to further examine and visualize the data can be found at https://gitlab.com/um-mip/mc-project-code. This research was supported by National Institute of Health/Eunice Kennedy Shriver National Institute of Child Health and Human Development R01 HD34860 and P50 HD28934. (1) Dulka EA, Moenter SM. Prepubertal development of gonadotropin-releasing hormone (GnRH) neuron activity is altered by sex, age and prenatal androgen exposure. Endocrinology 2017; 158:3941-3953 (2) Penix JJ, DeFazio RA, Dulka EA, Schnell S, Moenter SM. Firing patterns of gonadotropin-releasing hormone (GnRH) neurons are sculpted by their biology. Pending.
- Keyword:
- action potential, Monte Carlo, polycystic ovary syndrome, puberty, and androgen
- Citation to related publication:
- Dulka EA, Moenter SM. Prepubertal development of gonadotropin-releasing hormone neuron activity is altered by sex, age and prenatal androgen exposure. Endocrinology 2017; 158:3943-3953. https://dx.doi.org/10.1210%2Fen.2017-00768 and Penix JJ, DeFazio RA, Dulka EA, Schnell S, Moenter SM. Firing patterns of gonadotropin-releasing hormone (GnRH) neurons are sculpted by their biology. Pending.
- Discipline:
- Health Sciences