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River Road, ME, United States

Thomas College is a business and liberal arts College, located in Waterville, Maine, Thomas specializes in business, education, and technology. Thomas offers undergraduate and graduate degrees and is accredited by the New England Association of Schools and Colleges Wikipedia.

Carini M.T.,Western Kentucky University | Ryle W.T.,Thomas College
Astrophysical Journal | Year: 2012

The Seyfert 1 galaxy II ZW 229.015 has been observed with the Kepler spacecraft since quarter 4 of Kepler science operations. The results of the quarters 4-7 (1 year) Kepler observations are presented in this paper. We find the source to be highly variable on multiple timescales, with discrete variations occurring on timescales as short as tens of hours with amplitudes as small as 0.5%. Such small amplitude, rapid variability has never before been detected in active galactic nuclei. The presence of a strong galaxy component dilutes the variability determined from the photometric aperture used in the standard Kepler PDC analysis. Using the tools provided by the Kepler Guest Observer Office and simultaneous V-band photometry found in the literature, we determine an optimal customized aperture for photometry of this source with Kepler. The results of a PSRESP analysis reveal tentative evidence of a characteristic variability timescale in the power spectrum. Using this timescale, we estimate the mass of the central supermassive black hole and this estimate is consistent with the virial mass estimate from reverberation mapping studies. © 2012. The American Astronomical Society. All rights reserved.

Greenbaum L.E.,Thomas College | Wells R.G.,University of Pennsylvania
International Journal of Biochemistry and Cell Biology | Year: 2011

In response to liver injury or loss of liver mass, proliferation of mature liver cells is the first-line defense to restore liver homeostasis. In the setting of chronic liver disease, however, the ability of hepatocytes and cholangiocytes to proliferate is blocked and small bipotential progenitor cells are activated. Recent studies have established the role of these facultative progenitor cells in injury repair and fibrosis in patients with chronic liver disease and in experimental models. Several signaling pathways linking progenitor cell activation and fibrosis have been identified, and there is increasing evidence that cross-talk (both physical and via soluble factors) between progenitor cells and myofibroblasts is essential for both fibrosis and parenchymal regeneration. Even more exciting are new data examining the cellular components of the progenitor cell niche, demonstrating that both resident liver cells and circulating cells from the bone marrow can function as stem cells, suggesting that there is a surprising degree of phenotypic plasticity such that progenitor cells can contribute to the myofibroblast population and vice versa. We highlight here recent findings from the literature demonstrating the cellular and functional complexity of the progenitor cell niche, and emphasize some of the important questions that remain to drive future research. © 2010 Elsevier Ltd. All rights reserved.

Stevens R.G.,University of Connecticut Health Center | Brainard G.C.,Thomas College | Blask D.E.,Tulane University | Lockley S.W.,Harvard University | Motta M.E.,Tufts Medical School
CA Cancer Journal for Clinicians | Year: 2014

Breast cancer is the leading cause of cancer death among women worldwide, and there is only a limited explanation of why. Risk is highest in the most industrialized countries but also is rising rapidly in the developing world. Known risk factors account for only a portion of the incidence in the high-risk populations, and there has been considerable speculation and many false leads on other possibly major determinants of risk, such as dietary fat. A hallmark of industrialization is the increasing use of electricity to light the night, both within the home and without. It has only recently become clear that this evolutionarily new and, thereby, unnatural exposure can disrupt human circadian rhythmicity, of which three salient features are melatonin production, sleep, and the circadian clock. A convergence of research in cells, rodents, and humans suggests that the health consequences of circadian disruption may be substantial. An innovative experimental model has shown that light at night markedly increases the growth of human breast cancer xenografts in rats. In humans, the theory that light exposure at night increases breast cancer risk leads to specific predictions that are being tested epidemiologically: evidence has accumulated on risk in shift workers, risk in blind women, and the impact of sleep duration on risk. If electric light at night does explain a portion of the breast cancer burden, then there are practical interventions that can be implemented, including more selective use of light and the adoption of recent advances in lighting technology and application. CA Cancer J Clin 2014;64:207-218. © 2013 American Cancer Society. © 2013 American Cancer Society, Inc.

Mackeen A.D.,Thomas College
Cochrane database of systematic reviews (Online) | Year: 2012

Caesarean section is a common operation with no agreed upon standard regarding certain operative techniques or materials to use. With regard to skin closure, the skin incision can be re-approximated by a subcuticular suture immediately below the skin layer, by an interrupted suture, or by staples. A great variety of materials and techniques are used for skin closure after caesarean section and there is a need to identify which provide the best outcomes for women. To compare the effects of skin closure techniques and materials on maternal and operative outcomes after caesarean section. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (10 January 2012). All randomized trials comparing different skin closure materials in caesareans were selected. Two review authors independently abstracted the data. We identified 19 trials and included 11, but only eight trials contributed data. Three trials were not randomized controlled trials; two were ongoing; one study was terminated and the results were not available for review; one is awaiting classification; and one did not compare skin closure materials, but rather suture to suture and drain placement. The two methods of skin closure for caesarean that have been most often compared are non-absorbable staples and absorbable subcutaneous sutures. Compared with absorbable subcutaneous sutures, non-absorbable staples are associated with similar incidences of wound infection. Other important secondary outcomes, such as wound complications, were also similar between the groups in women with Pfannenstiel incisions. However, it is important to note, that for both of these outcomes (wound infection and wound complication), staples may have a differential effect depending on the type of skin incision, i.e., Pfannenstiel or vertical. Compared with absorbable subcutaneous sutures, non-absorbable staples are associated with an increased risk of skin separation, and therefore, reclosure. However, skin separation was variably defined across trials, and most staples were removed before four days postpartum. There is currently no conclusive evidence about how the skin should be closed after caesarean section. Staples are associated with similar outcomes in terms of wound infection, pain and cosmesis compared with sutures, and these two are the most commonly studied methods for skin closure after caesarean section. If staples are removed on day three, there is an increased incidence of skin separation and the need for reclosure compared with absorbable sutures.

John M.V.,Thomas College
Annals of Physics | Year: 2010

It is shown that a normalisable probability density can be defined for the entire complex plane in the modified de Broglie-Bohm quantum mechanics, which gives complex quantum trajectories. This work is in continuation of a previous one that defined a conserved probability for most of the regions in the complex space in terms of a trajectory integral, indicating a dynamical origin of quantum probability. There it was also shown that the quantum trajectories obtained are the same characteristic curves that propagate information about the conserved probability density. Though the probability density we now adopt for those regions left out in the previous work is not conserved locally, the net source of probability for such regions is seen to be zero in the example considered, allowing to make the total probability conserved. The new combined probability density agrees with the Born's probability everywhere on the real line, as required. A major fall out of the present scheme is that it explains why in the classical limit the imaginary parts of trajectories are not observed even indirectly and particles are confined close to the real line. © 2010 Elsevier Inc.

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