Panchromatic imaging and spectroscopic observations of the mass ejections of RY Scuti

We describe recent panchromatic imaging and spectroscopic studies of the supergiant, mass-transferring, binary star RY Scuti, which is in a brief transitional phase to become a Wolf-Rayet star and a stripped-envelope supernova.Comment: To appear in the proceedings of "Physics of Evolved Stars 2015 - A conference dedicated to the memory of Olivier Chesneau

Measuring effectiveness and value of email advertisements in relationship-oriented email messages

Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program; and, (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2008.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 63-70).This thesis explores the value of email advertisements in relationship-based communication by measuring click-through rates. Advertisements were embedded within standard electronic mail messages in a template. The results are discussed in aggregate to better understand this medium and value in an advertising context, but the analysis also breaks down how six factors affect click behavior by recipients. The factors include the impact of a privacy statement, type of organizational recipients, click timing, recent advertisements, advertisement frequency, and advertisement relevance. The results are also analyzed using a chi-squared statistical test to determine whether the individual factor is significant in this analysis. This paper also discusses the privacy implications of advertising in a social-medium with comparisons to social ads using Facebook's Beacon as a benchmark. A discussion of how these results apply in an email environment where anti-SPAM infrastructure is a large part of the overall system is evaluated as well. Results show that internal recipients are an effective target market for relationship messaging and that emails often generate clicks days or weeks after the original message was delivered. The research is very relevant to email and targeted advertising, but also applies in a broader context to social advertising where there is a existing relationship between a sender and recipient.by Dinesh Shenoy.S.M

SOFIA/FORCAST Observations of the Luminous Blue Variable Candidates MN 90 and HD 168625

We present SOFIA/FORCAST imaging of the circumstellar dust shells surrounding the luminous blue variable (LBV) candidates MN 90 and HD 168625 to quantify the mineral abundances of the dust and to constrain the evolutionary state of these objects. Our image at 37.1 micron of MN 90 shows a limb-brightened, spherical dust shell. A least-squares fit to the spectral energy distribution of MN 90 yields a dust temperature of 59 \pm 10 K, with the peak of the emission at 42.7 micron. Using 2-Dust radiative transfer code, we estimate for MN 90 that mass-loss occurred at a rate of (7.3 \pm 0.4)x10^-7 M_sun/yr x (v_exp/50 km/s) to create a dust shell with a dust mass of (3.2 \pm 0.1)x10^-2 M_sun. Our images between 7.7 - 37.1 micron of HD 168625 complement previously obtained mid-IR imaging of its bipolar nebulae. The SOFIA/FORCAST imaging of HD 168625 shows evidence for the limb-brightened peaks of an equatorial torus. We estimate a dust temperature of 170 \pm 40 K for the equatorial dust surrounding HD 168625, with the peak of the emission at 18.3 micron. Our 2-Dust model for HD 168625 estimates that mass-loss occurred at a rate of (3.2 \pm 0.2)x10^-7 M_sun/yr to create a dust torus/shell with a dust mass of (2.5 \pm 0.1)x10^-3 M_sun.Comment: 17 pages, 5 figures, accepted for publication in Ap

Surgical management of pterygium in a rural hospital using bare sclera versus conjunctival autograft technique

Background: Pterygium is defined as a triangular fibrovascular subepithelial ingrowth of degenerative bulbar conjunctival tissue over limbus onto the cornea. Commonly seen among farmers, fishermen, stone cutters and welders. Both blue and ultraviolet light have been implicated in its causation. Histologically the true Pterygium shows elastotic degeneration of the subconjunctival connective tissue. Pterygium warrant treatment when they encroach the visual axis, induces significant astigmatism or become cosmetically bothersome. My present study was undertaken to evaluate the efficacy, safety and recurrence rates of conjunctival autograft and bare sclera techniques in treatment of progressive true pterygium in a rural hospital.Methods: The prospective study was done in the Department of Ophthalmology, Adichunchanagiri Institute of Medical Sciences, B.G Nagara, Mandya District, Karnataka, India. The study was conducted for a period of 18 months. About 70 patients who presented with progressive pterygium were included in the study.Results: In our study pterygium recurred in 10 cases (14.28%), among which pterygium recurred in 8 cases (22.85 %) using bare sclera technique and in 2 patients (5.71%) using conjunctival autograft technique, best corrected visual acuity remained stable in 37 cases (52.85 %), improved in 33 cases (47.14 %) and worsened in none (0%) of the cases.Conclusions: Conjunctival autografting is a safe and effective procedure in the management of pterygium. The recurrence rate following limbal conjunctival autografting is significantly lower than that following primary conjunctival closure by bare sclera technique

Butorphanol for Post-Operative Analgesia - A Comparative Clinical Study with Ketorolac

Introduction: Butorphanol, an opioid derivative has been shown to have, in addition to its analgesic properties, several other advantageous effects like antistressor, sedative and anti-shivering action. The efficacy and safety profile of ketorolac, yet another widely used post-operative analgesic is well documented. This study aims to compare the two analgesics. Aims and objectives: This study was conducted to compare the analgesic efficacy and other effects of butorphanol and ketorolac, administered intramuscularly, in post-operative patients who have undergone lower abdominal and pelvic surgeries. Materials and methods: 50 patients undergoing lower abdominal and pelvic surgeries under general or spinal anaesthesia were randomly divided into two Groups (25 each). At a particular level of post-operative pain, the patients Groups I and II were administered intramuscular ketorolac 30mg and butorphanol 2mg respectively. The analgesic effect was studied using Visual Analogue Scale (VAS) and the verbal category scale. Patients were monitored for the sedative action, respiratory status and other vital parameters for 300 minutes and for other adverse reactions over the next twelve hours. Observations: Butorphanol provided better analgesia within the first two hours of administration, while ketorolac was more effective at 4-5 hours. Better sedative action without any significant respiratory depressant effect was demonstrated with butorphanol. There were no clinically significant hemodynamic fluctuations or adverse reactions with butorphanol or ketorolac. Conclusions: Butorphanol provides better early analgesia as compared to ketorolac with a desirable and safe sedative effect in post-operative patients who have undergone lower abdominal and pelvic surgeries