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Mountain Road, VA, United States

Hampden–Sydney College, also known as H-SC, is a liberal arts college for men located in Hampden Sydney, Virginia, United States. Founded in 1775, Hampden–Sydney is the oldest private charter college in the Southern U.S., the last college founded before the American Revolution, and one of only three four-year, all-men's liberal arts colleges in the United States. Wikipedia.

Hargadon K.M.,Hampden-Sydney College
International Reviews of Immunology | Year: 2016

Dendritic cells are a population of innate immune cells that possess their own effector functions as well as numerous regulatory properties that shape the activity of other innate and adaptive cells of the immune system. Following their development from either lymphoid or myeloid progenitors, the function of dendritic cells is tightly linked to their maturation and activation status. Differentiation into specialized subsets of dendritic cells also contributes to the diverse immunologic functions of these cells. Because of the key role played by dendritic cells in the regulation of both immune tolerance and activation, significant efforts have been focused on understanding dendritic cell biology. This review highlights the model systems currently available to study dendritic cell immunobiology and emphasizes the advantages and disadvantages to each system in both murine and human settings. In particular, in vitro cell culture systems involving immortalized dendritic cell lines, ex vivo systems for differentiating and expanding dendritic cells from their precursor populations, and systems for expanding, ablating, and manipulating dendritic cells in vivo are discussed. Emphasis is placed on the contribution of these systems to our current understanding of the development, function, and immunotherapeutic applications of dendritic cells, and insights into how these models might be extended in the future to answer remaining questions in the field are discussed. Copyright © Taylor and Francis Group, LLC. Source

The genus Trilasma Goodnight & Goodnight, 1942 is reinstated for Mexican ortholasmatines, and Cladolasma Suzuki, 1963 is reinstated for two species from Japan and Thailand, C. parvula Suzuki, comb. n. and C. angka (Schwendinger & Gruber), comb. n. Eight new species in the subfamily Ortholasmatinae Shear & Gruber, 1983 are described, as follows: Ortholasma colossus sp. n. is from California, Trilasma tempestado sp. n., T. hidalgo sp. n., T. trispinosum sp. n., T. ranchonuevo sp. n., T. petersprousei sp. n. and T. chipinquensis sp. n. are from México, and T. tropicum sp. n. from Honduras, the farthest south for a dyspnoan harvestman in the New World. A new distribution record for Martensolasma jocheni Shear, 2006 is given. The recently described Upper Cretaceous amber fossil Halitherses grimaldii Giribet & Dunlop, 2005 is not a member of the Ortholasmatinae, but is likely a troguloidean of an undiagnosed family. © William A. Shear. Source

Hesperonemastoma smilax, n. sp., is a minute, highly troglomorphic harvestman described herein from a single male specimen collected in McClung's Cave, Greenbrier County, West Virginia. Hesperonemastoma species described previously from caves are briefly discussed. H. packardi (Roewer), first collected in a shallow cave in Utah, is a widely distributed surface-dwelling species found mostly in riparian canyon habitats in northern Utah; it shows no troglomorphic adaptations. Hesperonemastoma inops (Packard), described from a cave in Kentucky, is not a species of Hesperonemastoma, but most likely a juvenile of Sabacon cavicolens (Packard), which was described from the same small cave. Hesperonemastoma pallidimaculosum (Goodnight and Goodnight) is a moderately adapted troglobiont known from two caves in Alabama. Source

Werth A.J.,Hampden-Sydney College
Journal of Experimental Biology | Year: 2013

Despite its vital function in a highly dynamic environment, baleen is typically assumed to be a static material. Its biomechanical and material properties have not previously been explored. Thus I tested sections of baleen from bowhead whales, Balaena mysticetus, and humpback whales, Megaptera novaeangliae, alone or in groups representing miniature 'racks', in a flow tank through which water and buoyant particles circulated with variable flow velocity. Kinematic sequences were recorded through an endoscopic camera or viewing window. One set of experiments investigated particle capture; another series analyzed biomechanical behavior, including fringe spacing, movement and interaction. Baleen fringe porosity directly correlates, in a mostly linear fashion, with velocity of incident water flow. However, undulation and interaction of fringes (especially of bowheads) at higher flow velocities can decrease porosity. Fringe porosity depends on distance from the baleen plate. Porosity also varies, with fringe length, by position along the length of an individual plate. Plate orientation, which varied from 0 to 90'deg relative to water flow, is crucial in fringe spacing and particle capture. At all flow velocities, porosity is lowest with plates aligned parallel to water flow. Turbulence introduced when plates rotate perpendicular to flow (as in cross-flow filtration) increases fringe interaction, so that particles more easily strike fringes yet more readily dislodge. Baleen of bowhead whales, which feed by continuous ram filtration, differs biomechanically from that of humpbacks, which use intermittent lunge filtration. The longer, finer fringes of bowhead baleen readily form a mesh-like mat, especially at higher flow velocities, to trap tiny particles. © 2013. Published by The Company of Biologists Ltd. Source

Shear W.A.,Hampden-Sydney College | Edgecombe G.D.,Natural History Museum in London
Arthropod Structure and Development | Year: 2010

We review issues of myriapod phylogeny, from the position of the Myriapoda amongst arthropods to the relationships of the orders of the classes Chilopoda and Diplopoda. The fossil record of each myriapod class is reviewed, with an emphasis on developments since 1997. We accept as working hypotheses that Myriapoda is monophyletic and belongs in Mandibulata, that the classes of Myriapoda are monophyletic, and that they are related as (Chilopoda (Symphyla (Diplopoda + Pauropoda))). The most pressing challenges to these hypotheses are some molecular and developmental evidence for an alliance between myriapods and chelicerates, and the attraction of symphylans to pauropods in some molecular analyses. While the phylogeny of the orders of Chilopoda appears settled, the relationships within Diplopoda remain unclear at several levels. Chilopoda and Diplopoda have a relatively sparse representation as fossils, and Symphyla and Pauropoda fossils are known only from Tertiary ambers. Fossils are difficult to place in trees based on living forms because many morphological characters are not very likely to be preserved in the fossils; as a consequence, most diplopod fossils have been placed in extinct higher taxa. Nevertheless, important information from diplopod fossils includes the first documented occurrence of air-breathing, and the first evidence for the use of a chemical defense. Stem-group myriapods are unknown, but evidence suggests the group must have arisen in the Early Cambrian, with a major period of cladogenesis in the Late Ordovician and early Silurian. Large terrestrial myriapods were on land at least by mid-Silurian. © 2009 Elsevier Ltd. All rights reserved. Source

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