The Chemical Compositions Of RR Lyrae Type C Variable Stars

We present a detailed chemical abundance study of eight RR Lyrae variable stars of subclass c (RRc). The target RRc stars chosen for study exhibit "Blazhko-effect" period and amplitude modulations to their pulsational cycles. Data for this study were gathered with the echelle spectrograph of the 100 inch du Pont telescope at Las Campanas Observatory. Spectra were obtained throughout each star's pulsation cycle. Atmospheric parameters-effective temperature, surface gravity, microturbulent velocity, and metallicity-were derived at multiple phase points. We found metallicities and element abundance ratios to be constant within observational uncertainties over the pulsational cycles of all stars. Moreover, the alpha-element and Fe-group abundance ratios with respect to iron are consistent with other horizontal-branch members (RRab, blue and red non-variables). Finally, we have used the [Fe/H] values of these eight RRc stars to anchor the metallicity estimates of a large-sample RRc snapshot spectroscopic study being conducted with the same telescope and instrument combination employed here.NSF AST-0908978, AST-1211585Baker Centennial Research EndowmentJohn W. Cox Endowment for the Advanced Studies in AstronomyMcDonald Observator

Boston Hospitality Review: Fall 2018 

Table of contents: Airbnb and the Hotel Industry: The Past, Present, and Future of Sales, Marketing, Branding, and Revenue Management By Makarand Mody and Monica Gomez -- Creating Community One Meal at a Time By Dana Searle -- Restaurant Delivery: Are the "ODP" the Industry's "OTA"? Part I & II By Christopher Muller -- My Head in the Clouds (Computing): A Case Study of a Restaurant Group Embracing Off-Site Technology By Tyler Titheringto

Using deuterated PAH amendments to validate chemical extraction methods to predict PAH bioavailability in soils

Validating chemical methods to predict bioavailable fractions of polycyclic aromatic hydrocarbons (PAHs) by comparison with accumulation bioassays is problematic. Concentrations accumulated in soil organisms not only depend on the bioavailable fraction but also on contaminant properties. A historically contaminated soil was freshly spiked with deuterated PAHs (dPAHs). dPAHs have a similar fate to their respective undeuterated analogues, so chemical methods that give good indications of bioavailability should extract the fresh more readily available dPAHs and historic more recalcitrant PAHs in similar proportions to those in which they are accumulated in the tissues of test organisms. Cyclodextrin and butanol extractions predicted the bioavailable fraction for earthworms (Eisenia fetida) and plants (Lolium multiflorum) better than the exhaustive extraction. The PAHs accumulated by earthworms had a larger dPAH:PAH ratio than that predicted by chemical methods. The isotope ratio method described here provides an effective way of evaluating other chemical methods to predict bioavailability

\u3cem\u3eGeysir\u3c/em\u3e: musical translation of geological noise

The sounds of geological phenomena are generally noise. Wind, glaciers, oceans, streams, and other geological sounds present a vast content of frequencies that often obscures individual pitches or groups of pitches. However, noise varies from sound to sound with different pitch predominance and patterns. This variance contributes to the signature that makes several noise-sounds unique. In this study, the sound of one of the geysers in the Geysir system of the Haukadalur valley, 180 miles Northeast of Reykjavik, Iceland, is recorded and analyzed in multiple time segments, each with its own pitch predominance and, therefore, signature. The analysis is further adapted into a piece for seven spatialized pianists and electronics titled Geysir, which features the amplitude and predominant pitch class fluctuations throughout the geyser sample. This paper reports the process of the analysis and the compositional applications of the pitch class predominance analysis

Searching for potential multi-hazard events during the last 1.5 million years of the Pleistocene epoch

Increasing attention has been paid to multi-hazards in environmental disaster studies produced during the last decade. Multi-hazard studies focus on the occurrence, interaction and effect of several natural hazards in the same region. Despite the increasing number of multi-hazard studies, few investigations have focused on global-scale multi-hazard events. With the aim of closing this gap, our study focuses on the identification of periods during the last 1.5 million years of the Pleistocene epoch, with the quasi-parallel appearance of natural hazards (e.g., asteroid impacts and large volcanic eruptions with a Volcanic Explosivity Index (VEI) of 8 and 7) amplifying their individual effects and thus causing long-term, global-scale changes. Of the seven identified potential multi-hazard events, three were considered as possible global-scale events with a longer term environmental (paleoclimatic) impact; dated to c.a., 1.4 Ma (marine isotope stage – MIS45), 1.0 Ma (MIS 27), and 100 ka (MIS 5c), respectively. Two additional periods (around 50 and 20 ka) were identified as being associated with more restricted scale multi-hazard events, which might cause a “Little Ice Age-like” climatic episode in the history of the Pleistocene Period. In addition, we present a hypothesis about the complex climatic response to a global-scale multi-hazard event consisting of a series of asteroid impacts and volcanic eruption linked to a geomagnetic polarity change, namely the Matuyama-Brunhes Boundary, which might be accompanied by global cooling and result in the final step of the Early Middle Pleistocene Transition

Med-Drop Pill Dispenser

Veterans’ Affairs home care nurses currently spend anywhere from thirty minutes to two hours filling out monthly prescriptions one pill at a time to veterans who are unable to leave their homes. The goal of this project was to create an easy-to-use device that could be left at a patient’s home that nurses could use to quickly and accurately dispense medication into the patient’s monthly pill box