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Solar cycle variation of plasma mass density in the outer magnetosphere: Magnetoseismic analysis of toroidal standing Alfven waves detected by Geotail 

Takahashi, Kazue; Denton, Richard; Hirahara, Masafumi; Min, Kyungguk; Ohtani, Shin-ichi; Sanchez, Ennio; 0000-0002-9565-6840; 0000-0003-1434-4456 (2023-01-25)
We study the variation of plasma mass density in the outer magnetosphere over a solar cycle using mass density estimated from the frequency of fundamental toroidal standing Alfven waves observed by the Geotail spacecraft. ...

TWINS stereoscopic imaging of multiple peaks in the ring current 

Perez, J; Goldstein, J; McComas, D; Valek, P; Buzulukova, N; Fok, M; Singer, H; 0000-0001-9500-866X; 0000-0002-2318-8750 (2023-01-25)
Global, ion equatorial flux distributions and energy spectra are presented from stereoscopic Two Wide-Angle Imaging Neutral-Atom Spectrometers (TWINS) 1 and TWINS 2 energetic neutral atom (ENA) images for two time periods, ...

Particle-in-Cell Simulations of the Fast Magnetosonic Mode in a Dipole Magnetic Field: 1-D Along the Radial Direction 

Min, Kyungguk; Liu, Kaijun; Denton, Richard; Boardsen, Scott; 0000-0001-5882-1328 (2023-01-26)
An electromagnetic particle-in-cell code is used to investigate self-consistent evolution of the fast magnetosonic mode in a one-dimensional configuration along the radial direction in a dipole background magnetic field. ...

Multi-Event Study on the Connection Between Subauroral Polarization Streams and Deep Energetic Particle Injections in the Inner Magnetosphere 

Califf, S; Zhao, H; Gkioulidou, M; Manweiler, J; Mitchell, D; Tian, S; 0000-0002-8800-2128; 0000-0001-8292-7691 (2023-01-25)
Energetic electron flux enhancements for 100s keV energies are often observed at low L shells (L < 4) in the inner magnetosphere during geomagnetic storms. However, protons with similar energies do not penetrate as deeply ...

Multi-Event Study on the Connection Between Subauroral Polarization Streams and Deep Energetic Particle Injections in the Inner Magnetosphere 

Califf, S; Zhao, H; Gkioulidou, M; Manweiler, J; Mitchell, D; Tian, S; 0000-0002-8800-2128; 0000-0001-8292-7691 (2023-01-25)
Energetic electron flux enhancements for 100s keV energies are often observed at low L shells (L < 4) in the inner magnetosphere during geomagnetic storms. However, protons with similar energies do not penetrate as deeply ...

Equatorial Evolution of the Fast Magnetosonic Mode in the Source Region: Observation-Simulation Comparison of the Preferential Propagation Direction 

Min, Kyungguk; Boardsen, Scott; Denton, Richard; Liu, Kaijun; 0000-0001-5882-1328 (2023-01-25)
Recent analysis of an event observed by the Van Allen Probes in the source region outside the plasmapause has shown that fast magnetosonic waves (also referred to as equatorial noise) propagate preferentially in the azimuthal ...

Outflow from the ionosphere in the vicinity of the cusp 

Valek, P; Perez, J; Jahn, J.-M; Pollock, C; Wüest, M; Friedel, R; Moore, T; Peterson, W; 0000-0002-2318-8750; 0000-0002-1513-6096 (2023-01-26)
[1] Low-energy ion outflows from the ionosphere are known to be an important source of plasma for the magnetosphere. The objective of this study is to describe the spatial relationships between low-energy ionospheric ...

Noble gas abundance and isotope ratios in the atmosphere of Jupiter from the Galileo Probe Mass Spectrometer 

Mahaffy, P; Niemann, H; Alpert, A; Atreya, S; Demick, J; Donahue, T; Harpold, D; Owen, T; 0000-0003-1896-1726 (2023-01-25)
The Galileo Probe Mass Spectrometer provided the first data on the noble gas mixing and isotope ratios in the Jovian atmosphere. These measurements and the comparison with solar values constrain models of Jupiter's formation. ...

Overlap of the plasmasphere and ring current: Relation to subauroral ionospheric heating 

Gurgiolo, C; Sandel, B; Perez, J; Mitchell, D; Pollock, C; Larsen, B; 0000-0003-4515-0208; 0000-0003-1960-2119 (2023-01-26)
The overlap of the ring current with the outer plasmasphere is thought to play a major role in storm-time related increases in the subauroral ambient topside electron temperature. Instabilities generated within the overlap ...

The Comprehensive Inner Magnetosphere-Ionosphere Model 

Fok, M; Buzulukova, N; Chen, S; Glocer, A; Nagai, T; Valek, P; Perez, J; 0000-0001-9500-866X; 0000-0001-9843-9094; 0000-0002-2318-8750 (2023-01-31)
Simulation studies of the Earth's radiation belts and ring current are very useful in understanding the acceleration, transport, and loss of energetic particles. Recently, the Comprehensive Ring Current Model (CRCM) and ...

Osmoregulation in the Hawaiian anchialine shrimp Halocaridina rubra (Crustacea: Atyidae): expression of ion transporters, mitochondria-rich cell proliferation and hemolymph osmolality during salinity transfers 

Havird, Justin C; Santos, Scott R; Henry, Raymond P (2019-08-08)
Studies of euryhaline crustaceans have identified conserved osmoregulatory adaptions allowing hyper-osmoregulation in dilute waters. However, previous studies have mainly examined decapod brachyurans with marine ancestries ...

Reptile Embryos Lack the Opportunity to Thermoregulate by Moving within the Egg 

Telemeco, Rory; Gangloff, Eric; Cordero, Gerardo; Mitchell, Timothy; Bodensteiner, Brooke; Holden, Kaitlyn; Mitchell, Sarah; Polich, Rebecca; Janzen, Fredric; 0000-0002-2101-3295; 0000-0002-7136-769X; 0000-0002-9137-1741 (2023-05-17)
Historically, egg-bound reptile embryos were thought to passively thermoconform to the nest environment. However, recent observations of thermal taxis by embryos of multiple reptile species have led to the widely discussed ...

The relative importance of life-history variables to population growth rate in mammals: Cole's prediction revisited 

Oli, Madan; Dobson, F. Stephen; 0000-0001-5562-6316 (2023-05-17)
The relative importance of life-history variables to population growth rate (lambda) has substantial consequences for the study of life-history evolution and for the dynamics of biological populations. Using life-history ...

Plumage color as a composite trait: Developmental and functional integration of sexual ornamentation 

Badyaev, Alexander; Hill, Geoffrey; Dunn, Peter; Glen, John; 0000-0002-7450-4194; 0000-0001-8864-6495 (2023-05-17)
Most studies of condition-dependent sexual ornaments have treated such ornaments as single traits. However, sexual ornaments are often composites of several components, each produced by partially independent developmental ...

Bacteria as an agent for change in structural plumage color: Correlational and experimental evidence 

Shawkey, Matthew; Pillai, Shreekumar; Hill, Geoffrey; Siefferman, Lynn; Roberts, Sharon; 0000-0001-8864-6495; 0000-0002-5131-8209; 0000-0002-9600-2902 (2023-05-17)
Recent studies have documented that a diverse assemblage of bacteria is present on the feathers of wild birds and that uropygial oil affects these bacteria in diverse ways. These findings suggest that birds may regulate ...

Magnetosheath Reconnection Before Magnetopause Reconnection Driven by Interplanetary Tangential Discontinuity: A Three-Dimensional Global Hybrid Simulation With Oblique Interplanetary Magnetic Field 

Guo, Zhifang; Lin, Yu; Wang, Xueyi; Du, Aimin; 0000-0002-3728-6319 (2022-10-27)
Terrestrial dayside dynamics associated with a southward turning, oblique interplanetary magnetic field (IMF) carried by an interplanetary tangential discontinuity (TD) is investigated by performing a three-dimensional ...

Why are incubation periods longer in the tropics? A common-garden experiment with house wrens reveals it is all in the egg 

Robinson, Douglas; Styrsky, John; Payne, Brian; Harper, Given; Thompson, Charles; 0000-0003-2240-0606 (2023-05-17)
Incubation periods of Neotropical birds are often longer than those of related species at temperate latitudes. We conducted a common-garden experiment to test the hypothesis that longer tropical incubation periods result ...

Micro- and Macroevolutionary Trade-Offs in Plant-Feeding Insects 

Peterson, Daniel; Hardy, Nate; Normark, Benjamin; 0000-0002-6267-9552; 0000-0002-3024-3068 (2023-05-17)
A long-standing hypothesis asserts that plant-feeding insects specialize on particular host plants because of negative interactions (trade-offs) between adaptations to alternative hosts, yet empirical evidence for such ...

Scalings for the Alfven-cyclotron instability: Linear dispersion theory and hybrid particle-in-cell simulations 

Gary, S. Peter; Fu, Xiangrong; Cowee, Misa M.; Winske, Dan; Liu, Kaijun; 0000-0003-3117-4030; 0000-0001-5882-1328; 0000-0002-4305-6624; 0000-0002-4655-2316 (2022-10-27)
The Alfven-cyclotron instability is driven by an ion temperature anisotropy such that T-perpendicular to/T-|| >1 where and || denote directions perpendicular and parallel to a uniform background magnetic field B-o, ...

Selective predation on Utah prairie dogs 

Hoogland, John; Cannon, Kristin; Manno, Theodore; DeBarbieri, Lili (2023-05-17)
Predation always affects demography and population dynamics, but removal of certain types of individuals is especially consequential. Predators strike quickly and commonly avoid areas with human observers, however, and ...