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Parkway, TN, United States

Rhodes College is a private, predominantly undergraduate, liberal arts college located in Memphis, Tennessee. Affiliated with the Presbyterian Church , Rhodes is accredited by the Southern Association of Colleges and Schools and enrolls approximately 1,800 students. Wikipedia.


Rupke D.S.N.,Rhodes College | Veilleux S.,University of Maryland University College
Astrophysical Journal Letters | Year: 2011

The quasi-stellar object (QSO)/merger Mrk 231 is arguably the nearest and best laboratory for studying QSO feedback. It hosts several outflows, including broad-line winds, radio jets, and a poorly understood kpc-scale outflow. In this Letter, we present integral field spectroscopy from the Gemini telescope that represents the first unambiguous detection of a wide-angle, kiloparsec-scale outflow from a powerful QSO. Using neutral gas absorption, we show that the nuclear region hosts an outflow with blueshifted velocities reaching 1100kms-1, extending 2-3kpc from the nucleus in all directions in the plane of the sky. A radio jet impacts the outflow north of the nucleus, accelerating it to even higher velocities (up to 1400kms-1). Finally, 3.5 kpc south of the nucleus, star formation is simultaneously powering an outflow that reaches more modest velocities of only 570kms-1. Blueshifted ionized gas is also detected around the nucleus at lower velocities and smaller scales. The mass and energy flux from the outflow are ≳2.5 times the star formation rate and ≳0.7% of the active galactic nucleus luminosity, consistent with negative feedback models of QSOs. © 2011. The American Astronomical Society. All rights reserved.


Rupke D.S.N.,Rhodes College | Veilleux S.,University of Maryland University College
Astrophysical Journal Letters | Year: 2013

We present Keck laser guide star adaptive optics observations of the nearby buried quasi-stellar object (QSO) F08572+3915:NW. We use near-infrared integral field data taken with the OH-Suppressing Infra-Red Imaging Spectrograph to reveal a compact disk and molecular outflow using Paα and H2 rotational-vibrational transitions at a spatial resolution of 100 pc. The outflow emerges perpendicular to the disk into a bicone of one-sided opening angle 100° up to distances of 400 pc from the nucleus. The integrated outflow velocities, which reach at least -1300 km s-1, correspond exactly to those observed in (unresolved) OH absorption, but are smaller (larger) than those observed on larger scales in the ionized (neutral atomic) outflow. These data represent a factor of >10 improvement in the spatial resolution of molecular outflows from mergers/QSOs, and plausibly represent the early stages of the excavation of the dust screen from a buried QSO. © 2013. The American Astronomical Society. All rights reserved..


Objective: To determine whether a prior live birth or an increase in number of miscarriages impacted the prevalence of congenital or acquired uterine anomalies in women with predominantly early recurrent miscarriage (RM). Design: Single-center, cross-sectional study. Setting: Patients with RM at a private practice. Patient(s): Eight hundred seventy-five women who had two or more consecutive miscarriages. Intervention(s): None. Main Outcome Measure(s): Frequencies of congenital uterine anomalies (bicornuate, didelphic, septate, t-shaped, and unicornuate uteri) and acquired uterine anomalies (fibroids, polyps, and adhesions). Result(s): A uterine anomaly was identified in 169 (19.3%) of the patients. Patients with primary RM were more likely to have congenital anomalies than patients with secondary RM, particularly septa. The occurrence of a prior live birth, however, did not influence the frequency of acquired uterine anomalies, which were detected in equal frequencies in patients with three or more miscarriages when compared with patients with only two miscarriages. Conclusion(s): Although RM patients with a prior viable birth are less likely to have a uterine anomaly than those who have never given birth, our results support a recommendation for diagnostic imaging of the uterus after two losses in women with secondary RM as well as for those with primary RM. © 2013 American Society for Reproductive Medicine, Published by Elsevier Inc.


Hoffmeister B.K.,Rhodes College
Physics in Medicine and Biology | Year: 2011

This study examines the frequency dependence of apparent ultrasonic backscatter from human cancellous bone as quantified by the apparent backscatter transfer function (ABTF). The term 'apparent' means that the backscatter signals are not compensated for the frequency-dependent effects of diffraction and attenuation. Backscatter measurements were performed in vitro on 22 specimens of bone using five transducers ranging in centre frequency from 1 to 10 MHz. The ABTF was measured at multiple sites and spatially averaged. The resulting spatially averaged ABTF (in dB) generally was a monotonically decreasing, quasi-linear function of frequency over the analysis bandwidth of the study (0.6-9.1 MHz). The apparent backscattered power tended to decrease with specimen density and become more strongly frequency dependent. Three parameters were determined from the spatially averaged ABTF. Apparent integrated backscatter (AIB) was determined by frequency averaging the spatially averaged ABTF. The frequency slope of apparent backscatter (FSAB) and the zero frequency intercept of apparent backscatter (FIAB) were determined from the slope and intercept of the spatially averaged ABTF, respectively. AIB and FSAB demonstrated moderate to good linear correlations with specimen density (|r| = 0.570-0.933). Correlations with density were weaker for the intercept-based parameter FIAB (|r| = 0.299-0.676). © 2011 Institute of Physics and Engineering in Medicine.


Grant
Agency: NSF | Branch: Standard Grant | Program: | Phase: PHYLOGENETIC SYSTEMATICS | Award Amount: 325.00K | Year: 2013

The seemingly endless diversity of flower shapes and colors captivates humans but evolved to entice pollinators in one of the most intricate and crucial biological interactions. This project tests the impact of floral diversity on speciation in the plant family Goodeniaceae, which is closely related to the large sunflower family. Goodeniaceae (400+ species) is one of the most species-rich and beautiful plant families in Australia and the Pacific Islands, and is particularly important to the Southwestern Australian Floristic Province, a threatened global biodiversity hotspot. The current taxonomic classification of these plants does not accurately reflect their evolutionary history, so a comprehensive revision of the group will be made using DNA sequences. Digital image analysis, floral symmetry gene expression, and the patterns of symmetry throughout development will be examined to quantify the species floral shape. Hypotheses of the impact of these shapes on rates of diversification will be assessed using this new information.

Undergraduate researchers will help study the interaction of insect pollinators with a subset of species in Western Australia. Students from the diverse communities of Memphis, Tennessee and Queens, New York will be an integral part of the project and will gain expertise in many aspects of molecular and evolutionary biology. This project will also help establish the conservation status of new and potentially rare species.

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