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Like their cellular host counterparts, many invading viral pathogens must contend with, modulate, and utilize the host cell's chromatin machinery to promote efficient lytic infection or control persistent-latent states. While not intended to be comprehensive, this review represents a compilation of conceptual snapshots of the dynamic interplay of viruses with the chromatin environment. Contributions focus on chromatin dynamics during infection, viral circumvention of cellular chromatin repression, chromatin organization of large DNA viruses, tethering and persistence, viral interactions with cellular chromatin modulation machinery, and control of viral latency-reactivation cycles.

Recently, we have witnessed the politicizing effects of police killings in the United States. This project asks how such killings might (de)mobilize voters at the local level. We draw on multiple theoretical approaches to develop a theory of community contact with the police. We argue that when a highly visible event tied to government actions occurs—like a police killing—it can spur turnout. This is especially true where public narratives tie such events to government and structural causes. By comparing neighborhoods near a killing before and after election day, we estimate the causal effect on turnout. We find a mobilizing effect. These effects are larger when they "trend" on Google, occur in Black communities, or if the victim is Black. Proximity to a killing also increases support for abolishing the police. We conclude that police violence increases electoral participation in communities where narratives about racially unjust policing resonate most. [ABSTRACT FROM AUTHOR]

This investigation explores memory performance using the California Verbal Learning Test in relation to morphometric and connectivity measures of the memory network in severe traumatic brain injury. Twenty-two adolescents with severe traumatic brain injury were recruited for multimodal MRI scanning 1–2 years post-injury at 13 participating sites. Analyses included hippocampal volume derived from anatomical T1-weighted imaging, fornix white matter microstructure from diffusion tensor imaging, and hippocampal resting-state functional magnetic resonance imaging connectivity as well as diffusion-based structural connectivity. A typically developing control cohort of forty-nine age-matched children also underwent scanning and neurocognitive assessment. Results showed hippocampus volume was decreased in traumatic brain injury with respect to controls. Further, hippocampal volume loss was associated with worse performance on memory and learning in traumatic brain injury subjects. Similarly, hippocampal fornix fractional anisotropy was reduced in traumatic brain injury with respect to controls, while decreased fractional anisotropy in the hippocampal fornix also was associated with worse performance on memory and learning in traumatic brain injury subjects. Additionally, reduced structural connectivity of left hippocampus to thalamus and calcarine sulcus was associated with memory and learning in traumatic brain injury subjects. Functional connectivity in the left hippocampal network was also associated with memory and learning in traumatic brain injury subjects. These regional findings from a multi-modal neuroimaging approach should not only be useful for gaining valuable insight into traumatic brain injury induced memory and learning disfunction, but may also be informative for monitoring injury progression, recovery, and for developing rehabilitation as well as therapy strategies. [ABSTRACT FROM AUTHOR]

NMR spectroscopy was used to investigate the binding of cationic counterions to anionic micelles formed by undecyl LL-leucinevalaninate (und-LV). Amino acid-based surfactants like und-LV are green alternatives to commercial surfactants. Monomeric and polymeric forms of und-LV micelles have also been used as chiral selectors in capillary electrophoresis (CE) separations. The counterions investigated were Na+, the tetraethylammonium ion, L-Lysine, 1,4-diaminobutane, 1,6-diaminohexane, and cis and trans isomers of 1,2-diaminocyclohexane and 1,4-diaminocyclohexane. NMR measurements of counterion and micelle diffusion coefficients were used to calculate micelle radii and the mole fraction of counterion molecules bound to the micelles. Two-dimensional NMR experiments were used to investigate the structures of the counterion: micelle complexes. The mole fraction of bound counterions did not change with pH in solutions containing Na+ or tetraethylammonium counterions. With all other counterions, however, the mole fraction of micelle-bound counterions was higher below pH 10 when counterions had a + 1 or +2 charge, and lower above pH 10–10.5 when the counterions were neutral or zwitterionic. Changes in micelle radii with pH and two-dimensional NMR experiments suggested that L-Lysine, 1,4-diaminobutane, and 1,6-diaminohexane bound parallel to the micelle surface with their amine functional groups interacting with different surfactant monomers. In contrast, the diaminocyclohexane isomers were found to bind perpendicular to the micelle surface. The mole fractions of micelle-bound cis-1,4-diaminocyclohexane and trans-1,4-diaminocyclohexane were very similar to one another. However, with 1,2-cyclohexanediamine, at low pH the mole fraction of micelle-bound counterions was larger for the cis isomer than for the trans isomer. [ABSTRACT FROM AUTHOR]