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Eastchester, NC, United States

Laurel University is an accredited, private interdenominational Christian college that delivers undergraduate, graduate and doctoral degree programs in on-campus, online, and in blended environments.Laurel University is located in High Point, just 15 miles south of Greensboro, North Carolina in the central Piedmont Triad area. The university offers a rural campus and stresses the importance of traditional family values, Judeo-Christian ethics, and biblical morality. Wikipedia.

Skok J.R.,Brown University | Mustard J.F.,Brown University | Ehlmann B.L.,Brown University | Milliken R.E.,University of Notre Dame | Murchie S.L.,Laurel University
Nature Geoscience

The martian surface features abundant volcanoes and evidence for past liquid water. Extant or relict martian volcanic hydrothermal systems have therefore been sought in the pursuit of evidence for habitable environments 1. The Mars Exploration Rover, Spirit, detected deposits highly enriched in silica with accessory minerals, suggesting formation by hydrothermal leaching of basaltic rocks by low-pH solutions 2. However, extensive erosion has obscured the context of the formation environment of these deposits. Silica deposits have also been identified remotely, but also with limited contextual clues to their formation; aqueous alteration products of basalt and volcanic ash are the most likely sources 3,4. Here we report the detection from orbit of hydrated silica deposits on the flanks of a volcanic cone in the martian Syrtis Major caldera complex. Near-infrared observations show dozens of localized hydrated silica deposits. As a result of the morphology of these deposits and their location in and around the cone summit, we suggest that the deposits were produced by a volcanically driven hydrothermal system. The cone and associated lava flows post-date Early Hesperian volcano formation. We conclude that, if a relict hydrothermal system was associated with the silica deposits, it may preserve one of the most recent habitable microenvironments on Mars. © 2010 Macmillan Publishers Limited. All rights reserved. Source

Raouafi N.-E.,Laurel University | Stenborg G.,George Mason University
Astrophysical Journal

We report on the role of small-scale, transient magnetic activity in the formation and evolution of solar coronal plumes. Three plumes within equatorial coronal holes are analyzed over the span of several days based on the Solar Dynamic Observatory (SDO)/Atmospheric Imaging Assembly 171 Å and 193 Å images and SDO/Helioseismic and Magnetic Imager line-of-sight magnetograms. The focus is on the role of transient structures at the footpoints in sustaining coronal plumes for relatively long periods of time (i.e., several days). The appearance of plumes is a gradual and lengthy process. In some cases, the initial stages of plume formation are marked by the appearance of pillar-like structures whose footpoints are the sources of transient brightenings. In addition to nominal jets occurring prior to and during the development of plumes, the data show that a large number of small jets (i.e., "jetlets") and plume transient bright points (PTBPs) occur on timescales of tens of seconds to a few minutes. These features are the result of quasi-random cancellations of fragmented and diffuse minority magnetic polarity with the dominant unipolar magnetic field concentration over an extended period of time. They unambiguously reflect a highly dynamical evolution at the footpoints and are seemingly the main energy source for plumes. This suggests a tendency for plumes to be dependent on the occurrence of transients (i.e., jetlets, and PTBPs) resulting from low-rate magnetic reconnection. The decay phase of plumes is characterized by gradual fainting and multiple rejuvenations as a result of the dispersal of the unipolar magnetic concentration and its precipitation into multiple magnetic centers. © 2014. The American Astronomical Society. All rights reserved. Source

McCord T.B.,Bear Fight Institute | Castillo-Rogez J.,Jet Propulsion Laboratory | Rivkin A.,Laurel University
Space Science Reviews

Ceres appears likely to be differentiated and to have experienced planetary evolution processes. This conclusion is based on current geophysical observations and thermodynamic modeling of Ceres' evolution. This makes Ceres similar to a small planet, and in fact it is thought to represent a class of objects from which the inner planets formed. Verification of Ceres' state and understanding of the many steps in achieving it remains a major goal. The Dawn spacecraft and its instrument package are on a mission to observe Ceres from orbit. Observations and potential results are suggested here, based on number of science questions. © Springer Science+Business Media B.V. 2011. Source

Patel T.J.,Laurel University | Beredjiklian P.K.,Rothman Institute | Matzon J.L.,Rothman Institute
Current Reviews in Musculoskeletal Medicine

Trapeziometacarpal (TM) joint arthritis is a common cause of radial-sided wrist pain that preferentially affects women. It is diagnosed by a thorough history, physical examination, and radiographic evaluation. While radiographs are used to determine the stage of disease, treatment is dependent on symptom severity. Nonoperative treatment frequently consists of activity modification, non-steroidal anti-inflammatory drugs (NSAIDs), splinting, and corticosteroid injections. After failure of conservative treatment, various surgical options exist depending on the stage of disease. This article reviews the literature supporting the various surgical treatment options. Special consideration is given to the comparison of trapeziectomy with and without tendon interposition and ligament reconstruction. © 2012 Springer Science+Business Media New York. Source

Goncharenko L.P.,Massachusetts Institute of Technology | Hsu V.W.,University of Colorado at Boulder | Brum C.G.M.,National Astronomy and Ionosphere Center | Zhang S.-R.,Massachusetts Institute of Technology | Fentzke J.T.,Laurel University
Journal of Geophysical Research: Space Physics

This paper presents a case study of the day-to-day variability in the midlatitude upper atmospheric ion temperature (∼200-400 km) with a focus on variability resulting from meteorological forcing. The data are obtained by the Millstone Hill incoherent scatter radar (42.6°N, 288.5°E) on 18-31 January 2010, in coincidence with a major sudden stratospheric warming. We elucidate oscillations in ion temperature with both tidal periods (∼8 h and ∼12 h) and non-tidal periods (>24 h) by analyzing residuals between the observed temperatures and those expected from an empirical model. We present the spatial-temporal development of periodicities in ion temperature and discuss to what degree these periodicities might be related to the sudden stratospheric warming event. The spectral location and temporal evolution of periodicities with ∼9.9-12.9 h and ∼6.2-7.9 h suggest that they are related to the semidiurnal (12 h) and terdiurnal (8 h) tides that are enhanced during the sudden stratospheric warming. Periodicities with ∼3-4 d and ∼10-13 d are likely related to Rossby waves with 4 d and 10 d periods, while the strong periodicity observed at 16-17 h could result from the nonlinear interaction of the quasi 2 d wave with the semidiurnal tide. As planetary waves are not expected to propagate to altitudes of ∼200-250 km, these experimental results raise questions about the potential mechanisms of coupling between the lower and upper atmosphere. © 2012. American Geophysical Union. All Rights Reserved. Source

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