Van Regenmorter, Roger

Roger Van Regenmorter was drafted in 1965, and he served in an infantry division in Vietnam. In his interview, he discusses his experiences in Vietnam, including a battle on July 4, 1966. He also elaborates on his feelings about the war and its aftermath. Date of interview: March 31, 2007Length of interview:113:5

Functional evolution of the feeding system in rodents

The masticatory musculature of rodents has evolved to enable both gnawing at the incisors and chewing at the molars. In particular, the masseter muscle is highly specialised, having extended anteriorly to originate from the rostrum. All living rodents have achieved this masseteric expansion in one of three ways, known as the sciuromorph, hystricomorph and myomorph conditions. Here, we used finite element analysis (FEA) to investigate the biomechanical implications of these three morphologies, in a squirrel, guinea pig and rat. In particular, we wished to determine whether each of the three morphologies is better adapted for either gnawing or chewing. Results show that squirrels are more efficient at muscle-bite force transmission during incisor gnawing than guinea pigs, and that guinea pigs are more efficient at molar chewing than squirrels. This matches the known diet of nuts and seeds that squirrels gnaw, and of grasses that guinea pigs grind down with their molars. Surprisingly, results also indicate that rats are more efficient as well as more versatile feeders than both the squirrel and guinea pig. There seems to be no compromise in biting efficiency to accommodate the wider range of foodstuffs and the more general feeding behaviour adopted by rats. Our results show that the morphology of the skull and masticatory muscles have allowed squirrels to specialise as gnawers and guinea pigs as chewers, but that rats are high-performance generalists, which helps explain their overwhelming success as a group

Increasing leaf hydraulic conductance with transpiration rate minimizes the water potential drawdown from stem to leaf.

Leaf hydraulic conductance (k leaf) is a central element in the regulation of leaf water balance but the properties of k leaf remain uncertain. Here, the evidence for the following two models for k leaf in well-hydrated plants is evaluated: (i) k leaf is constant or (ii) k leaf increases as transpiration rate (E) increases. The difference between stem and leaf water potential (ΔΨstem-leaf), stomatal conductance (g s), k leaf, and E over a diurnal cycle for three angiosperm and gymnosperm tree species growing in a common garden, and for Helianthus annuus plants grown under sub-ambient, ambient, and elevated atmospheric CO₂ concentration were evaluated. Results show that for well-watered plants k leaf is positively dependent on E. Here, this property is termed the dynamic conductance, k leaf(E), which incorporates the inherent k leaf at zero E, which is distinguished as the static conductance, k leaf(0). Growth under different CO₂ concentrations maintained the same relationship between k leaf and E, resulting in similar k leaf(0), while operating along different regions of the curve owing to the influence of CO₂ on g s. The positive relationship between k leaf and E minimized variation in ΔΨstem-leaf. This enables leaves to minimize variation in Ψleaf and maximize g s and CO₂ assimilation rate over the diurnal course of evaporative demand

Engineering a New Home: Creating a Repository Collection for Faculty

Open Scholarship provides access to the scholarly output of faculty, staff, and students from Washington University in St. Louis by gathering it in one place. On May 9, 2011, the Faculty Senate passed the Open Access Resolution in order to make scholarship and creative works freely and easily available to the world community. The Open Scholarship site was officially launched on March 26, 2012 as a platform for realizing this goal. Powered by bepress\u27s Digital Commons, and supported by the Libraries’ Digital Library Services, Open Scholarship is a further step in the University\u27s commitment to open access. However, populating the collections beyond electronic theses and dissertations (ETDs) has been inconsistent, and most faculty materials are added one article at a time across a handful of departments. In summer 2014, the Computer Science and Engineering (CSE) department contacted its subject librarian Lauren Todd about moving their technical reports from the department’s private SharePoint repository to Open Scholarship. Todd consulted with Emily Stenberg, the Digital Publishing and Digital Preservation librarian. Together with the CSE project manager and an involved professor, Todd and Stenberg formulated a plan to develop a collection in which faculty could submit their new reports and the subject librarian could administer the collection. They also established a local workflow making use of GoogleDrive (based on a workflow documented by Cleveland State University librarians) to batch upload earlier technical reports from the department’s SharePoint site. This was the first collection developed in Open Scholarship for an entire department in a comprehensive manner. The scope of the collection expanded beyond technical reports to include other faculty contributions, including conference materials and published research. The CSE collection has led to other engineering collections in Open Scholarship and extended the range of materials available in the repository.https://openscholarship.wustl.edu/lib_present/1017/thumbnail.jp

Engineering a New Home: Creating a Repository Collection for Faculty AND Building a Larger Digital Presence for the School of Engineering

This talk is an expanded version of one given at the 2015 MOBIUS conference. Washington University librarians Emily Stenberg and Lauren Todd explain how they created and manage a collection in the university’s repository Open Scholarship for the Computer Science and Engineering department. This presentation will highlight how they developed a step-by-step workflow, addressed customization requests from the department, what really happened once that plan was implemented, and how they handle Bepress troubleshooting and faculty concerns. The presenters will also discuss how this project has helped them offer Open Scholarship as a service to other engineering faculty.https://openscholarship.wustl.edu/lib_present/1020/thumbnail.jp

it Feels Like I\u27m a Step Closer to My Ultimate Goal of Stable Housing: a Qualitative Study of Unhoused People\u27s Experiences in Alternative Shelters in Portland

In recent years, alternatives to congregate shelters have emerged, including tiny home villages and motel conversions. Existing research indicates that these alternative shelter modalities are associated with positive outcomes for shelter guests. This qualitative study was conducted with 11 participants staying in three alternative shelters tailored to support specific groups: lesbian, bisexual, gay, transgender, queer, intersex, and asexual (LGBTQIA+) people, women, and medically vulnerable people. Participants reported a number of facilitators and barriers to meeting their personal goals (e.g., permanent housing, medical care). Key facilitators included the relative privacy, autonomy, and safety of alternative shelters, and support for guests with marginalized identities. Barriers included difficulty navigating housing systems, and lack of internet and mail access. Given the drawbacks of congregate shelters, these new models are promising options to support unhoused people when permanent housing is not yet available

Young Stars with SALT

We present a spectroscopic and kinematic analysis of 79 nearby M dwarfs in 77 systems. All are low-proper-motion southern hemisphere objects and were identified in a nearby star survey with a demonstrated sensitivity to young stars. Using low-resolution optical spectroscopy from the Red Side Spectrograph (RSS) on the South African Large Telescope (SALT), we have determined radial velocities, H-alpha, Lithium 6708\AA, and Potassium 7699\AA~equivalent widths linked to age and activity, and spectral types for all our targets. Combined with astrometric information from literature sources, we identify 44 young stars. Eighteen are previously known members of moving groups within 100 parsecs of the Sun. Twelve are new members, including one member of the TW Hydra moving group, one member of the 32 Orionis moving group, nine members of Tucana-Horologium, one member of Argus, and two new members of AB Doradus. We also find fourteen young star systems that are not members of any known groups. The remaining 33 star systems do not appear to be young. This appears to be evidence of a new population of nearby young stars not related to the known nearby young moving groups.Comment: 23 pages, 11 figures, 6 tables. Accepted to Ap

Immunostaining for Homer reveals the majority of excitatory synapses in laminae I-III of the mouse spinal dorsal horn

The spinal dorsal horn processes somatosensory information before conveying it to the brain. The neuronal organization of the dorsal horn is still poorly understood, although recent studies have defined several distinct populations among the interneurons, which account for most of its constituent neurons. All primary afferents, and the great majority of neurons in laminae I–III are glutamatergic, and a major factor limiting our understanding of the synaptic circuitry has been the difficulty in identifying glutamatergic synapses with light microscopy. Although there are numerous potential targets for antibodies, these are difficult to visualize with immunocytochemistry, because of protein cross-linking following tissue fixation. Although this can be overcome by antigen retrieval methods, these lead to difficulty in detecting other antigens. The aim of this study was to test whether the postsynaptic protein Homer can be used to reveal glutamatergic synapses in the dorsal horn. Immunostaining for Homer gave punctate labeling when viewed by confocal microscopy, and this was restricted to synapses at the ultrastructural level. We found that Homer puncta were colocalized with the AMPA receptor GluR2 subunit, but not with the inhibitory synapse-associated protein gephyrin. We also examined several populations of glutamatergic axons and found that the great majority of boutons were in contact with at least one Homer punctum. These results suggest that Homer antibodies can be used to reveal the great majority of glutamatergic synapses without antigen retrieval. This will be of considerable value in tracing synaptic circuits, and also in investigating plasticity of glutamatergic synapses in pain states