Climate system asymmetries drive eccentricity pacing of hydroclimate during the early Eocene greenhouse.

The early Eocene Climatic Optimum (EECO) represents the peak of Earth's last sustained greenhouse climate interval. To investigate hydroclimate variability in western North America during the EECO, we developed an orbitally resolved leaf wax δ2H record from one of the most well-dated terrestrial paleoclimate archives, the Green River Formation. Our δ2Hwax results show ∼60‰ variation and evidence for eccentricity and precession forcing. iCESM simulations indicate that changes in the Earth's orbit drive large seasonal variations in precipitation and δ2H of precipitation at our study site, primarily during the summer season. Our findings suggest that the astronomical response in δ2Hwax is attributable to an asymmetrical climate response to the seasonal cycle, a "clipping" of precession forcing, and asymmetric carbon cycle dynamics, which further enhance the influence of eccentricity modulation on the hydrological cycle during the EECO. More broadly, our study provides an explanation for how and why eccentricity emerges as a dominant frequency in climate records from ice-free greenhouse worlds.

Developing a Multi-Tiered System of Support-Based Plan for Bullying Prevention Among Students with Disabilities: Perspectives from General and Special Education Teachers During Professional Development.

Students with disabilities or at risk for disability identification (SWD) are disproportionately affected by the bullying dynamic; however, professional development and educator-focused training on preventing bullying for this population is lacking. To address this gap, this study presents an analysis of qualitative data collected from general and special education teachers (n = 33) participating in an online professional development training using Multi-Tiered System of Supports (MTSS) to prevent bullying among students with disabilities. Braun and Clarke's six-step process was used to identify key themes and exemplar quotes from qualitative reflections collected as knowledge check responses embedded within two training modules. Three themes were identified and examined based on MTSS tiers: (1) teacher perceptions of SWD and their inclusion in a MTSS-based bullying prevention plan; (2) identifying key stakeholders for preventing bullying within a MTSS-based bullying prevention plan; and (3) potential challenges and solutions of implementing a MTSS-based bullying prevention plan within the individual, classroom, and school contexts. Findings highlight the need to educate teachers on how to use MTSS, especially for bullying prevention and interventions that are inclusive of SWD. Implications from this work extend to all students including those with mental health considerations, regardless of disability status. Supplementary Information: The online version contains supplementary material available at 10.1007/s12310-023-09589-8.

BBAP monoubiquitylates histone H4 at lysine 91 and selectively modulates the DNA damage response.

Although the BBAP E3 ligase and its binding partner BAL are overexpressed in chemotherapy-resistant lymphomas, the role of these proteins in DNA damage responses remains undefined. Because BAL proteins modulate promoter-coupled transcription and contain structural motifs associated with chromatin remodeling and DNA repair, we reasoned that the BBAP E3 ligase might target nucleosomal proteins. Herein, we demonstrate that BBAP selectively monoubiquitylates histone H4 lysine 91 and protects cells exposed to DNA-damaging agents. Disruption of BBAP-mediated monoubiquitylation of histone H4K91 is associated with the loss of chromatin-associated H4K20 methylase, mono- and dimethyl H4K20, and a delay in the kinetics of 53BP1 foci formation at sites of DNA damage. Because 53BP1 localizes to DNA damage sites, in part, via an interaction with dimethyl H4K20, these data directly implicate BBAP in the monoubiquitylation and additional posttranslational modification of histone H4 and an associated DNA damage response.