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Cenozoic exhumation in Marie Byrd Land (MBL), West Antarctica, has been dominated by uplift of the MBL dome, an ~800 by ~300 km topographic swell thought to be supported by a hot mantle anomaly, and West Antarctic ice sheet (WAIS) development resulting in deeply incised glacial troughs with up to 3 km of local relief. WAIS expansion is thought to potentially coincide with uplift of the MBL dome, which would have provided the elevated topography necessary to nucleate and grow a continental ice sheet beginning sometime between 34 – 20 Ma. Temporal and spatial relationships between these events remain unclear, however. This study investigates the timing, magnitude, and spatial relationships between tectonic uplift and glacial incision in MBL by leveraging thermo-kinematic modeling informed by detrital low-temperature thermochronology. We investigated Neogene detrital seafloor sediment samples from 14 dredge and core sites along the coast of MBL. Apatite He ages (closure temp ~60°C) of detrital samples range from 23.5 to >80 Ma. Most detrital ages are significantly younger than the ~80 Ma ages typical of exposed bedrock across the region, suggesting these originate from deeply incised bedrock of glacial troughs. The youngest ages obtained for samples retrieved from offshore central and eastern MBL are also significantly younger than the youngest ages obtained for samples from western MBL, suggesting spatial heterogeneity in the timing and/or magnitude of exhumation across the region. Thermo-kinematic modeling of western MBL suggests the regional exhumation rate has been low (10-3 km/myr) since 80 Ma, although focused erosion in glacial troughs produced local late Cenozoic exhumation rates as high as 0.15 km/myr. Preliminary models of the DeVicq glacial trough region of central MBL support these patterns of exhumation. Although model predictions generally agree with observed detrital age distributions, incorporation of detrital ages into these models is expected to provide new insight into the timing of WAIS inception, as well as rates and magnitudes of glacial incision across MBL. 

Bird migration has fascinated natural historians and scientists for centuries. While the timing of migration is known to vary by species, population, sex, and individual, identifying the cause of this variation can be challenging. Here we investigate factors underlying migratory timing in a long- distance migratory bird, the Common Yellowthroat (Geothlypas trichas), using a population genomic approach. We begin by creating a map of genetic variation across geographic space (a “genoscape”) using lcWGS from across the breeding range. We then utilize genetic assays to assign 249 wintering and 1050 northward migrating birds to genetically distinct breeding populations. Additionally, we estimate the expected spring onset date in each predicted breeding region and calculate the remaining migratory distance for northward migrating birds. Our findings indicate that when population genetic structure is not a factor in the analysis, it appears that birds captured early in the season are migrating to breeding grounds where spring arrives later, which contrasts with prior research. However, when we incorporate population structure into our analysis, our results align with predictions, indicating that birds captured earlier in the season are indeed heading to breeding grounds where spring arrives earlier. Further analysis revealed that the disparity between results obtained with and without population genetic structure can be attributed to the fact that individuals from the western genetic group migrate three times the distance to the west, despite breeding at the same latitude. Our findings suggest that categorizing large numbers of migrating birds into genetically distinct groups can reveal population-specific patterns in migratory timing and shed light on the relative contributions of different selective forces responsible for the observed patterns. 

The human auditory system consists of both peripheral and central components, both of which play a role but contribute distinctly to overall auditory functioning and can be differentially impacted by pathophysiologic states. Hemispheric surgery (HS), a procedure used for the treatment of drug-resistant epilepsy, involves com- plete disconnection of the auditory cortex in the operative hemisphere, leaving hearing acuity (peripheral function) intact but having heavy implications for auditory processing (central function). The literature describing pre- and post-operative auditory processing abilities of individuals who have undergone HS is sparse, but the research available provides evidence that several central auditory processes including auditory spatial analysis and temporal processing may be impacted. De昀椀cits noted in standardized testing within the clinical or research environment have concrete functional impacts that may be currently under-appreciated and could lead to under-utilization of appropriate therapeutic strategies and accommodations. This review describes the pro昀椀le of central auditory processing abilities in patients who have undergone HS by synthesizing available literature and incorporating research in other clinical populations to help 昀椀ll critical gaps in our understanding of how cerebral disconnection impacts the central auditory system. 

Abstract Repetitive mild head injuries incurred while playing organized sports, during car accidents and falls, or in active military service are a major health problem. These head injuries induce cognitive, motor, and behavioral deficits that can last for months and even years with an increased risk of dementia, Parkinson’s disease, and chronic traumatic encephalopathy. There is no approved medical treatment for these types of head injuries. To this end, we tested the healing effects of the psychedelic psilocybin, as it is known to reduce neuroinflammation and enhance neuroplasticity. Using a model of mild repetitive head injury in adult female rats, we provide unprecedented data that psilocybin can reduce vasogenic edema, restore normal vascular reactivity and functional connectivity, reduce phosphorylated tau buildup, enhance levels of brain-derived neurotrophic factor and its receptor TrkB, and modulate lipid signaling molecules. 

Formation kinetics of metal nanoparticles are generally describedviamass transport and thermodynamics‐based models, such as diffusion‐limited growth and classical nucleation theory (CNT). However, metal monomers are commonly assumed as precursors, leaving the identity of molecular intermediates and their contribution to nanoparticle formation unclear. Herein, liquid phase transmission electron microscopy (LPTEM) and reaction kinetic modeling are utilized to establish the nucleation and growth mechanisms and discover molecular intermediates during silver nanoparticle formation. Quantitative LPTEM measurements show that their nucleation rate decreases while growth rate is nearly invariant with electron dose rate. Reaction kinetic simulations show that Ag₄and Ag⁻follow a statistically similar dose rate dependence as the experimentally determined growth rate. We show that experimental growth rates are consistent with diffusion‐limited growthviathe attachment of these species to nanoparticles. The dose rate dependence of nucleation rate is inconsistent with CNT. A reaction‐limited nucleation mechanism is proposed and it is demonstrated that experimental nucleation kinetics are consistent with Ag₄²⁺aggregation rates at millisecond time scales. Reaction throughput analysis of the kinetic simulations uncovered formation and decay pathways mediating intermediate concentrations. We demonstrate the power of quantitative LPTEM combined with kinetic modeling for establishing nanoparticle formation mechanisms and principal intermediates. 

Does war deepen gender inequalities in politicians’ behavior or help erase them? We draw from the terror management theory developed in psychology to argue that the onset of a violent conflict is likely to push politicians to conform more strongly with traditional gender stereotypes because it helps individuals cope with existential fears. To test our argument, we use data on Ukrainian politicians’ engagement on social media (136,455 Facebook posts by 469 politicians) in the three months before and after the 2022 Russian invasion of Ukraine, and interrupted time series analysis, to assess the effect of conflict on politicians’ behavior. We find that conflict onset deepens gender-stereotypical behavior among politicians in their public engagement. We also show that, consistent with our argument, gender biases among the public are magnified during war.