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Abstract Galbut virus is a remarkably successful virus of the model organism Drosophila melanogaster. The ease of capturing galbut virus–infected wild flies presents an opportunity to study persistent virus–host interactions. To better understand galbut virus diversity, evolution, and genotype–phenotype relationships, we screened 957 flies collected from 13 locations across the USA. Galbut virus was detected in every population, and overall, 75% of flies tested positive. We selected 149 flies for shotgun RNA sequencing and recovered 368 coding-complete or near-complete sequences of galbut virus and its likely satellite, chaq virus. Galbut virus sequences clustered phylogenetically into three major clades. Two clades, termed melA and melB, comprised mainly viruses infecting D. melanogaster, while the third, simA, included D. simulans-infecting viruses. Between-clade pairwise nucleotide identity was as low as 75%, but diversity within clades was low. Geography partly explained phylogenetic clustering: some sequences from the same location were identical or nearly identical, while others were spread throughout trees. Several genotype–phenotype associations emerged, including higher average RNA levels in melA infections and an exclusive association of chaq virus with melA and simA infections. Coinfection was detected in 11% of samples and did not require complete sets of all three galbut virus segments. Coinfection is a prerequisite of reassortment, and there was evidence of reassortment involving all segments and chaq virus. However, reassortment did not occur between clades, despite coinfection, indicating that clades are reproductively isolated. Galbut virus RNA 3 sequences exhibited more involvement in coinfection, greater diversity, and stronger evidence of diversifying selection than the other segments, consistent with a possible role in host modulation. These findings corroborated the ecological success of galbut virus and reveal the need for experiments to uncover the mechanisms underlying reassortment incompatibility and clade-specific phenotypes. 

Substituting the central proline residue in a collagen mimetic peptide with δ-oxaproline affords a faster-folding analogue with equivalent triple helix stability. 

ABSTRACT Numerous management methods are deployed to try to mitigate the destructive impact of weedy and invasive populations. Yet, such management practices may cause these populations to inadvertently evolve in ways that have consequence on their invasiveness. To test this idea, we conducted a two‐step field mesocosm experiment; we evolved genetically diverse populations of the duckweedLemna minorto targeted removal management and then tested the impact of that evolution in replicated invasions into experimental resident communities. We found that evolution in response to management increased invasiveness compared to populations evolved without management. This evolution in response to management had little effect on the impact of the invader on the resident species. These results illustrate the potential eco‐evolutionary consequences of management practices. Mitigating evolution to physical removal, in addition to pesticides, may be important to the long‐term success of integrated pest management. 

Designing robots to support high-stakes teamwork in emergency settings presents unique challenges, including seamless integration into fast-paced environments, facilitating effective communication among team members, and adapting to rapidly changing situations. While teleoperated robots have been successfully used in high-stakes domains such as frefght- ing and space exploration, autonomous robots that aid high- stakes teamwork remain underexplored. To address this gap, we conducted a rapid prototyping process to develop a series of seemingly autonomous robots designed to assist clinical teams in the Emergency Room. We transformed a standard crash cart—which stores medical equipment and emergency supplies into a medical robotic crash cart (MCCR). The MCCR was evaluated through feld deployments to assess its impact on team workload and usability, identifed taxonomies of failure, and refned the MCCR in collaboration with healthcare professionals. Our work advances the understanding of robot design for high-stakes, time-sensitive settings, providing insights into useful MCCR capabilities and considerations for effective human-robot collaboration. By publicly disseminating our MCCR tutorial, we hope to encourage HRI researchers to explore the design of robots for high-stakes teamwork. 

Cybersickness – discomfort caused by virtual reality (VR) – remains a significant problem that negatively affects the user experience. Research on individual differences in cybersickness has typically focused on overall sickness intensity, but a detailed understanding should include whether individuals differ in the relative intensity of cybersickness symptoms. This study used latent profile analysis (LPA) to explore whether there exist groups of individuals who experience common patterns of cybersickness symptoms. Participants played a VR game for up to 20 min. LPA indicated three groups with low, medium, and high overall cybersickness. Further, there were similarities and differences in relative patterns of nausea, disorientation, and oculomotor symptoms between groups. Disorientation was lower than nausea and oculomotor symptoms for all three groups. Nausea and oculomotor were experienced at similar levels within the high and low sickness groups, but the medium sickness group experienced more nausea than oculomotor. Characteristics of group members varied across groups, including gender, virtual reality experience, video game experience, and history of motion sickness. These findings identify distinct individual experiences in symptomology that go beyond overall sickness intensity, which could enable future interventions that target certain groups of individuals and specific symptoms. 

Clean and renewable energy development is becoming frontier research for future energy resources, as renewable energy offers sustainable and environmentally friendly alternatives to non-renewable sources such as fossil fuels. Among various renewable energy sources, tremendous progress has been made in converting solar energy to electric energy by developing efficient organic photovoltaics. Organic photovoltaic materials comprising conjugated polymers (CP) with narrow optical energy gaps are promising candidates for developing sustainable sources due to their potentially lower manufacturing costs. Organic semiconductor materials with a high electron affinity are required for many optoelectronic applications. We have designed a series of organic semiconductors comprised of cyclopentadithiophene as a donor and thiadiazoloquinoxaline (TQ) as an acceptor, varying the π-conjugation and TQ-derivatives. We have employed density functional theory (DFT) and time-dependent DFT (TDDFT) to evaluate the designed CP’s optoelectronic properties, such as optical energy gap, dipole moment, and absorption spectra. Our DFT/TDDFT result shows that the energy gap of CPs is lowered and redshifted in the absorption spectra if there is no insertion of conjugation units such as thiophene and selenophene between donor and acceptor. In addition, selenophene shows relatively better redshift behavior compared to thiophene. Our work also provides rational insight into designing donor/acceptor-based CPs for organic solar cells.