Suppurative Pododermatitis

On July 17, 1951 a one-year-old Guernsey heifer was admitted to the Stange Memorial Clinic. She was lame on the left front leg. Further examination of the affected leg revealed a fistultous opening on the lateral side of the claw just above the hoof. The owner suspected a foreign body, possibly a piece of glass, to be the causative factor

Microfilariae in the Skin of the Horse

On Aug. 12, 1952, a Hackney pony stallion was admitted to the Stange Memorial Clinic for a skin examination. At the posterior part of the neck, adjacent to the shoulder, was a raised, hairless area about 3 by 5 inches which contained several secondary nodules about the size of a marble. The skin of the area seemed to be abnormally thickened and it was more deeply pigmented than the unaffected skin. Just posterior to the olecranon at approximately the eleventh rib, on both sides of the animal, were solitary, raised, hairless areas about one inch in diameter. These appeared to be of the same nature as the larger area on the neck. No signs of pruritis were observed

Developing an In Vitro Assay for Detection and Characterization of Functional Connectivity within Transplantation Candidate Embryonic Stem Cell-Derived V2a Interneuron Networks

Facilitating plasticity after spinal cord injury tends to be the focus of most modern interventions for this condition. In particular, stem cell therapies attempt to both modulate and mimic some of the native plasticity after injury through multiple mechanisms. One such mechanism, the creation of new exogenous relay circuits bridging the injury, has been explored extensively, revealing serious impediments to its optimization and adoption for clinical settings. Our collaborator, the Sakiyama-Elbert group, has spent years addressing the first limitation, the variability of cellular graft composition, by perfecting protocols to generate embryonic stem cell (ESC)-derived populations of neurons with pre-determined genetic identity. Recently, they developed a protocol to develop highly-enriched populations of Chx10-expressing V2a interneurons (INs), a ventral interneuron population that has garnered recent interest due to its role in central pattern generating function and favorable phenotypic properties. This predominantly glutamatergic and long, ipsilaterally projecting population appears to be a prime candidate for transplantation therapies for SCI, especially for the creation of relay circuits that can potentially circumnavigate injuries. The research documented in this thesis attempts to begin to address the second limitation of stem cell transplantation therapy, our minimal understanding of intra-graft network connectivity after transplantation. Due to the limitations of current techniques for evaluating the connectivity of populations like ESC-derived V2a INs, the relationship between functional recovery and the functional properties of the novel circuits formed within the graft still eludes researchers. This thesis focuses on the development of an assay capable of rapidly detecting connectivity within ESC-derived candidate populations. By extending previous work in the stem cell field, we combine in vitro multi-electrode arrays (MEAs) with an extensively studied metric of functional connectivity, cross-correlation, to detect and characterize individual functional connections between ESC-derived neurons. We first validated this assay by culturing ESC-derived populations differentiated for increased expression of Chx10 on MEAs. We found that both dissociated and aggregated cultures formed functional busting networks with significant functional connectivity detected with the use of Between-Sample Analysis of Connectivity, a methodology originally developed for in vitro circadian networks. Aggregated networks, however, had much more consistent electrode coverage and individual neuron detection that dissociated networks. After this validation study, we characterized the functional connectivity within highly-enriched populations of ESC-V2a INs, comparing their connectivity to populations of ESC-MN/glia and mixed populations of ESC-V2a/MN/glia. We found that ESC-MN/glia aggregates formed active networks with a variety of activity and functional connectivity that was dependent on the transmission of glutamate. ESC-V2a INs could only survive out to the 4-week time point if they were grown in media conditioned with glial factors, but these cultures still lacked spontaneous extracellular activity. Mixed ESC-V2a/MN/glia populations formed the most active networks and had thousands of detectable connections which were also dependent on glutamate transmission. Application of glycine antagonist modulated network activity but the underlying cause is fairly inconclusive due to possible secondary effects. High growth factor concentrations in the growth media actually decreased network activity and detectable functional connections in the mixed populations. All of these findings in this proof of concept study collectively suggest that a mixture of ESC-V2a INs and ESC-MN/glia may be the most viable candidate for transplantation and sets the stage for future investigations into the manipulability of their connectivity with electrical stimulation, as well as scaled versions of this assay performed in combination with animal studies

Evaluating Multicultural Literature for Use in the Classroom

Books should not be chosen simply because they have minority characters and are available

Civic Economies: Commerce, Regulation, and Public Space in the Antebellum City

Between 1790 and 1860, the governance of Baltimore and Philadelphia transformed to meet the demands of a capitalist economy predicated on moving people and goods ever more rapidly and indiscriminately. Far from being an era of diminished governmental oversight, however, the early republic saw a dramatic expansion in local and state regulation of urban economies and spaces, as newly minted municipal corporations endeavored to carve out spheres of economic and political influence and protect consumers and public welfare. They did so through market houses, licensing, product inspection, nuisance laws, and a bevy of other instruments. In response, men and women from across the social spectrum—from widows selling oranges to railroad corporations—shaped urban regulation and promoted their own visions of the market, enacting a civic economy. Through a study of thousands of petitions to city leaders, as well as city records and legislation, “Civic Economies” builds upon recent scholarship that has recovered a robust tradition of regulation in antebellum America. But it goes further to show how local variations, competing legal interpretations, and dynamics of class, gender, and race suffused regulatory institutions. “Civic Economies” also probes the myriad forms and meanings of capitalism in antebellum America. Understanding capitalism in the context of human-scale spaces like the market house, sidewalk, and neighborhood, petitioners tended not to view regulation and capitalism as oppositional forces. Beginning in the 1820s, however, other conceptions of capitalism—emblematized by railroads, global trade, and abstract markets—exerted greater influence over urban governance. Increasingly, economic and political elites used regulation to promote the free and efficient circulation of people, capital, and goods, rather than to ensure fair competition and just prices. Responsibility for market governance devolved from the state to urban capitalists operating through corporations and boards of trade. Municipal product inspection collapsed in the 1840s under the weight of free trade arguments, while private market houses proliferated at the expense of municipal market houses. Meanwhile, city leaders embarked on transforming urban space and governance in the image of nineteenth-century liberalism, promoting freedom of mobility and anchoring social inequalities in the built landscape—a pair of antebellum legacies that continues to shape American urbanism

Long-term thinking in UK family business

This working paper explores long-term thinking in family businesses based in the United Kingdom. The objectives of the paper are: to investigate the emergence and impact of long-term orientation (LTO) within family business; to explore the fit between LTO and specific types of family business; to investigate the balance between short-term and long-term orientations in these firms; and to explore the associated risks that may attach to both types of orientation. The data collection process for this research project comprised two stages: first, data were collected via surveys of senior members of family businesses; secondly, to help clarify the findings from the first stage, three individual family business case studies were conducted in order to provide a deeper account of family firms’ experience of LTO. The research findings offer new insights into UK family businesses in terms of their long- term objectives and strategies, non-economic goals, and LTO in the context of continuity, perseverance and legacy. The paper concludes with practical recommendations for consideration by both family and non-family stakeholders, pending further research on the subject

Cooling of cryogenic electron bilayers via the Coulomb interaction

Heat dissipation in current-carrying cryogenic nanostructures is problematic because the phonon density of states decreases strongly as energy decreases. We show that the Coulomb interaction can prove a valuable resource for carrier cooling via coupling to a nearby, cold electron reservoir. Specifically, we consider the geometry of an electron bilayer in a silicon-based heterostructure, and analyze the power transfer. We show that across a range of temperatures, separations, and sheet densities, the electron-electron interaction dominates the phonon heat-dissipation modes as the main cooling mechanism. Coulomb cooling is most effective at low densities, when phonon cooling is least effective in silicon, making it especially relevant for experiments attempting to perform coherent manipulations of single spins.Comment: 9 pages, 5 figure