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.
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.
Shear W.A.,Hampden-Sydney College
ZooKeys | Year: 2010
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.
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.
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.
Hargadon K.M.,Hampden-Sydney College
Frontiers in Immunology | Year: 2013
Dendritic cells (DC) are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programing of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti-tumor immunity. © 2013 Hargadon.
Agency: NSF | Branch: Continuing grant | Program: | Phase: Integrative Ecologi Physiology | Award Amount: 118.01K | Year: 2014
The unPAK project (undergraduates Phenotyping Arabidopsis Knockouts) uses the plant Arabidopsis thaliana to examine how and when differences in DNA sequences lead to differences in traits related to survival, growth, and reproduction. It will detect effects, if any, of mutation in a comprehensive collection of mutants generated by the SALK Institute, and will then compile results in a comprehensive database. To examine the interaction of genetic and environmental effects, unPAKs experiments are replicated within and across multiple growth facilities and labs, and a subset of experiments deliberately manipulate soil factors, moisture, and temperature to see how these important ecological factors interact with genetics.
unPAK will survey enough mutant lines to reach coverage of a third of the A. thaliana genome (approximately 9,000 genes). All data are uploaded into a public database at arabidopsisunpak.org, and the unPAK project links its database of observed traits to existing genomic databases. Evidence produced by unPAK will enable testing central hypotheses about the relationship between genomic features and important plant characteristics. For example, the data can be used to test whether the effects of mutation are predicted by gene attributes such as molecular signatures of selection in the past, gene function, gene family size, or by patterns of variability in natural populations.
unPAK is centered around participation of undergraduate researchers in the lab and the classroom, educating and training undergraduates integratively in genetics, ecology, evolution, and bioinformatics. The network extends across diverse post-secondary institutions, with over 100 undergraduate apprentices participating across 13 laboratories in 3 years. Greater than 20 course-based undergraduate research experiences (CUREs) will be supported by the program, reaching over 600 students. Any discoveries about the influence of particular genes on fruit production, survival, or life history will have significant broader impacts in potential application to crop species.
As a final part of the project the unPAK research network itself is being studied. Using mixed-methods approaches from the social sciences, researchers are documenting interactions among network participants to analyze changes in network structure over time, and to investigate factors that influence student participation and outcomes, including students? accrual of human, cultural, and social capital.
Agency: NSF | Branch: Standard Grant | Program: | Phase: INFORMATION TECHNOLOGY RESEARC | Award Amount: 42.77K | Year: 2015
This project explores balancing performance considerations and power consumption in cyber-physical systems, through algorithms that switch among different modes of operation (e.g., low-power/high-power, on/off, or mobile/static) in response to environmental conditions. The main theoretical contribution is a computational, hybrid optimal control framework that is connected to a number of relevant target applications where physical modeling, control design, and software architectures all constitute important components. The fundamental research in this program advances state-of-the-art along four different dimensions, namely (1) real-time, hybrid optimal control algorithms for power management, (2) power-management in mobile sensor networks, (3) distributed power-aware architectures for infrastructure management, and (4) power-management in embedded multi-core processors.
The expected outcome, which is to enable low-power devices to be deployed in a more effective manner, has implications on a number of application domains, including distributed sensor and communication networks, and intelligent and efficient buildings. The team represents both a research university (Georgia Institute of Technology) and an undergraduate teaching university (York College of Pennsylvania) in order to ensure that the educational components are far-reaching and cut across traditional educational boundaries. The project involves novel, inductive-based learning modules, where graduate students team with undergraduate researchers.
Agency: NSF | Branch: Continuing grant | Program: | Phase: Integrative Ecologi Physiology | Award Amount: 113.17K | Year: 2011
What is the effect of a mutation that knocks out a single gene in an organisms genome? Unsatisfyingly, todays plant geneticists can only say: It depends. Only a small minority of mutations are lethal or have a significant impact. For the vast majority, at most only subtle effects have been detected. Plant genetics is poised to progress rapidly in remedying this situation, using a collection of knockout mutant strains of the model species Arabidopsis thaliana. Knockouts, carrying a tiny tagged segment of disruptive DNA in one targeted gene, are already available for ~67% of the 27,000+ unique genes in this plants genome. Inspired by progress in yeast genetics, the project will grow large subsets of these knockouts in benign and challenging environments, quantifying ecological performance attributes (e.g., population growth rate, fruit yield). We predict that, as in yeast, such an approach will reveal important phenotypic differences between mutant and control lines and possibly reveal undiscovered genome-wide patterns. The project is a collaboration of primarily undergraduate institutions and will train young scientists in how major genomic questions are addressed by networks of researchers.
The project will involve screening 7000 available T-DNA lines to identify those that have mutations at only one gene, providing these results to the biological community. Traits relevant to plant performance will be measured in over 3000 single-mutant lines, across multiple environments. Cyberinfrastructure will be developed to disseminate common protocols and to archive and index data. Over 50 undergraduate researchers will be involved in collecting and analyzing data and communicating results. The project also includes a study of how participating in a distributed research network influences undergraduates access to social capital within the scientific community. Results from this aspect of the work will lay the foundation for a larger scale, empirical study of the outcomes undergraduates realize by participating in research networks.
Agency: NSF | Branch: Standard Grant | Program: | Phase: EVOLUTIONARY GENETICS | Award Amount: 32.03K | Year: 2016
This award supports a gathering of faculty and student representatives from 11 institutions that participate in the Undergraduates Phenotyping Arabidopsis Knockouts (unPAK). Representatives from research universities, liberal arts colleges, community colleges, and historically minority-serving institutions, will attend the meeting in Austin, Texas in June 2016. The meeting will give students the opportunity to organize and participate in a professional gathering and faculty the opportunity to strategize on the directions the unPAK network will take in the future. Students will plan and work with faculty in the development of workshops that will address current issues with unPAK as well as potential future collaborative directions. These workshops are expected to include development of new techniques for research, comparison of data collection and analysis techniques between institutions, discussion of ways to integrate unPAK research into classroom settings, and improvement of dissemination strategies of unPAK data to the scientific community. The meeting will aid in expanding knowledge of plant genetics in support of developing better agricultural strategies for economically-critical crops while providing the next generation of scientists with networking and presentation skills necessary to launch their careers.
Founded in 2010 (NSF award #1052262) and expanded in 2014 (NSF award #1355106), the Undergraduates Phenotyping Arabidopsis Knockouts (unPAK) project has sought to provide undergraduates with the opportunity to engage in authentic and collaborative research using Arabidopsis thaliana as a model system. This meeting is designed to support the long-term development and sustainability of unPAK, by bringing student and faculty representatives of all unPAK institutions together in Austin, TX from June 15-17, 2016 in conjunction with the Evolution 2016 meeting. Faculty will participate in both their own planning sessions as well as sessions with students. A major focus of the meeting will be on promoting student interactions to support their development as scientists. The meeting will provide a venue for in-person interaction that excites and inspires students to pursue careers in scientific research, and will improve unPAKs ability to efficiently deliver A. thaliana deletion line genotypic and phenotypic data by sharing best practices among all students and faculty in the unPAK network. By bringing together students from a wide range of institutional types, this meeting will also expose participating students and faculty to the many ways in which unPAK is engaging undergraduates in the advancement of scientific knowledge about plant genetics.
Hampden-Sydney College | Date: 2010-08-18
Methods and apparatuses for converting methanol to higher hydrocarbons in a continuous process. A distillation column may be packed with inert material and filled with an ionic liquid. The ionic liquid may function as both reaction medium and catalyst. Derivative of zinc iodide and indium iodide may serve as the possible catalytic species. Higher hydrocarbons may be isolated from reaction effluent by condensation in a cold-water condenser, a cold trap, or both.