The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25–50%) than euchromatic reference regions (3–11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11–27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4–3.6 vs. 8.4–8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu.

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Background: The transition period from hospital to home is a highly vulnerable time for patients after stroke. COVID-19 restrictions have exacerbated safety concerns, stressed the health care system, and put patients at high risk after discharge. Here we describe pilot results from the Joint Stroke Transitional Technology-Enhanced Program (JSTTEP) designed to reduce post-stroke complications, avoid hospital readmission, and enhance recovery. Methods: JSTTEP is a novel, interprofessional program for patients discharged from the Johns Hopkins Comprehensive Stroke Center. In the first weeks after hospital discharge, stroke patients complete a series of multidisciplinary telemedicine visits to (1) reduce the risks of adverse events in the transition from hospital to home, and (2) develop a plan to facilitate a full recovery. The first joint visit is with stroke neurology and physical therapy for risk mitigation, and the second is with physiatry and occupational therapy for a recovery plan. Patients and caregivers participate in an interactive, online group education session covering topics about vascular risk factor modification, nutrition, exercise, fall prevention, and self-management skills. Results: In the first 4 months of the program, 50 patients were enrolled. Average age was 61 years; 26/50 (52%) were women, 23/50 (46%) were African American, and mean baseline NIHSS was 5.4. Of those 45/50 (90%) completed their visit, with 4/50 (8%) requiring conversion from video to phone visit. Unexpected 30-day hospital readmission rate was 3/50 (6%), one of whom was readmitted due to neurological issues identified during the JSTTEP appointment. Interpreter services were utilized for 5 completed video visits (Arabic, Mandarin, Spanish, Twi, Urdu). Patients reported the ability to include family members remotely in the visit as an advantage. Conclusions: The data demonstrate the feasibility and potential benefit of an interprofessional stroke telemedicine program designed to enhance post-stroke recovery. JSTTEP increased access to post-hospital care and reduced risks for adverse outcomes. The ongoing benefits and scaling of such a clinic will rely on permanent legislative and insurance changes to support such a care model.

This article describes how the Penn State University Libraries have responded to the unique challenges that the COVID-19 pandemic presents to international student populations. Additionally, the authors discuss support and service programs for international students that may ease the disruptions expected in upcoming semesters. A collaborative approach is emphasized as the libraries work in coordination with stakeholders across the institution to address COVID-19 issues.

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