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Fibrin forms the structural scaffold of blood clots and has great potential for biomaterial applications. Creating recombinant expression systems of fibrinogen, fibrin’s soluble precursor, would advance the ability to construct mutational libraries that would enable structure–function studies of fibrinogen and expand the utility of fibrin as a biomaterial. Despite these needs, recombinant fibrinogen expression systems, thus far, have relied on the time-consuming creation of stable cell lines. Here we present tests of a transient fibrinogen expression system that can rapidly generate yields of 8–12 mg/L using suspension HEK Expi293TM cells. We report results from two different plasmid systems encoding the fibrinogen cDNAs and two different transfection reagents. In addition, we describe a novel, affinity-based approach to purifying fibrinogen from complex media such as human plasma. We show that using a high-affinity peptide which mimics fibrin’s knob ‘A’ sequence enables the purification of 50–75% of fibrinogen present in plasma. Having robust expression and purification systems of fibrinogen will enable future studies of basic fibrin(ogen) biology, while paving the way for the ubiquitous use of fibrin as a biomaterial. 

In this descriptive brief paper about work in progress, two science education university faculty and a post-doctoral researcher share an arts-based assessment developed to investigate students’ understanding of computational thinking. The mark out poetry activity was designed for use in an NSF grant funded mixed methods, multi-partner STEM-C research project. Piloted in an undergraduate science teacher education course at a public university, the assessment is intended for later use with public high school juniors and seniors who are partnering in the grant’s work, and likely have little experience with computational thinking. Collected data has the potential to inform the researchers about changes in participants’ understanding of computational thinking over time, as well as the efficacy of the equity-based grant project. This paper includes instructions for the activity, an example of one undergraduate’s work, and a preliminary analysis of the work of the five students in the pilot. This presentation may inform the work of constituents of technological, teacher education, and K-12 learning communities who want to broaden and deepen their assessment practices with the inclusion of qualitative, arts- and equity-based data collection and analysis. (Funding-NSF Grant 1842342.) 

As demands for wildlife tourism increase, provisioning has become a popular means of providing up-close viewing to the public. At Monkey Mia, Shark Bay, Australia, up to five adult female Indo-Pacific bottlenose dolphins ( Tursiops aduncus ) visit a 100 m stretch of beach daily to receive fish handouts. In 2011, a severe marine heatwave (MHW) devastated seagrass and fish populations in Shark Bay. Offspring survival declined precipitously among seagrass specialists (dolphins that forage disproportionately in seagrass habitat). As all provisioned dolphins at the site are seagrass specialists, we examined how provisioned and non-provisioned seagrass specialists responded to the MHW. Using 27 years of data we compare habitat use, home range size, calf mortality, and predation risk between provisioned and non-provisioned females and their offspring before and after the MHW. Our results show that provisioned females have extremely small home ranges compared to non-provisioned females, a pattern attributable to their efforts to remain near the site of fish handouts. However, weaned offspring (juveniles) born to provisioned females who are not provisioned themselves also had much smaller home ranges, suggesting a persistent maternal effect on their behavior. After the MHW, adult females increased their use of seagrass habitats, but not their home range size. Provisioned females had significantly lower calf mortality than non-provisioned females, a pattern most evident pre-MHW, and, in the first 5 years after the MHW (peri-MHW, 2011–2015), calf mortality did not significantly increase for either group. However, the ecosystem did not recover, and post-MHW (2016–2020), calf mortality was substantially higher, regardless of provisioning status. With few survivors, the impact of the MHW on juvenile mortality post-weaning is not known. However, over three decades, juvenile mortality among offspring of provisioned vs. non-provisioned females did not statistically differ. Thus, the survival benefits accrued to calves in the provisioned group likely cease after weaning. Finally, although shark attack rates on seagrass specialists did not change over time, elevated predation on calves cannot be ruled out as a cause of death post-MHW. We discuss our results as they relate to anthropogenic influences on dolphin behavioral plasticity and responses to extreme climate events. 

ABSTRACT For insects known as parasitoid wasps, successful development as a parasite results in the death of the host insect. As a result of this lethal interaction, wasps and their hosts have coevolved strategies to gain an advantage in this evolutionary arms race. Although normally considered to be strict pathogens, some viruses have established persistent infections within parasitoid wasp lineages and are beneficial to wasps during parasitism. Heritable associations between viruses and parasitoid wasps have evolved independently multiple times, but most of these systems remain largely understudied with respect to viral origin, transmission and replication strategies of the virus, and interactions between the virus and host insects. Here, we report a detailed characterization of Diachasmimorpha longicaudata entomopoxvirus (DlEPV), a poxvirus found within the venom gland of Diachasmimorpha longicaudata wasps. Our results show that DlEPV exhibits similar but distinct transmission and replication dynamics compared to those of other parasitoid viral elements, including vertical transmission of the virus within wasps, as well as virus replication in both female wasps and fruit fly hosts. Functional assays demonstrate that DlEPV is highly virulent within fly hosts, and wasps without DlEPV have severely reduced parasitism success compared to those with a typical viral load. Taken together, the data presented in this study illustrate a novel case of beneficial virus evolution, in which a virus of unique origin has undergone convergent evolution with other viral elements associated with parasitoid wasps to provide an analogous function throughout parasitism. IMPORTANCE Viruses are generally considered to be disease-causing agents, but several instances of beneficial viral elements have been identified in insects called parasitoid wasps. These virus-derived entities are passed on through wasp generations and enhance the success of the wasps’ parasitic life cycle. Many parasitoid-virus partnerships studied to date exhibit common features among independent cases of this phenomenon, including a mother-to-offspring route of virus transmission, a restricted time and location for virus replication, and a positive effect of virus activity on wasp survival. Our characterization of Diachasmimorpha longicaudata entomopoxvirus (DlEPV), a poxvirus found in Diachasmimorpha longicaudata parasitoid wasps, represents a novel example of beneficial virus evolution. Here, we show that DlEPV exhibits functional similarities to known parasitoid viral elements that support its comparable role during parasitism. Our results also demonstrate unique differences that suggest DlEPV is more autonomous than other long-term viral associations described in parasitoid wasps.