Infrared Line Emission from Planetary Nebulae. I - General Theory

General theory of infrared line emission from planetary nebul

Organic Geochemistry of Fatty Acids

The aims of organic geochemistry included the investigation of the distribution of specific classes of organic compounds and the rigorous identification of the individual components interred in geological materials. Assuming that the organic matter present in a rock is of biological origin, it is of particular interest to investigate classes of compounds which are present in biological systems and which have been preserved in sediments. A number of workers have isolated and identified alkanes and fatty acids in sediments; this thesis is concerned with the examination of sedimentary fatty acids

Unlocking Rosenberger\u27s Research

Homer Rosenberger\u27s unprocessed collection lies in Musselman Library\u27s Special Collections--a multitude of boxes filled with Pennsylvania research and memorabilia. By examining the first box in the collection, it becomes clear that Rosenberger was more than just an avid researcher, but also a man with his own history and reasons for collecting these documents in the first place

Swift observations of the 2015 outburst of AG Peg -- from slow nova to classical symbiotic outburst

Symbiotic stars often contain white dwarfs with quasi-steady shell burning on their surfaces. However, in most symbiotics, the origin of this burning is unclear. In symbiotic slow novae, however, it is linked to a past thermonuclear runaway. In June 2015, the symbiotic slow nova AG Peg was seen in only its second optical outburst since 1850. This recent outburst was of much shorter duration and lower amplitude than the earlier eruption, and it contained multiple peaks -- like outbursts in classical symbiotic stars such as Z And. We report Swift X-ray and UV observations of AG Peg made between June 2015 and January 2016. The X-ray flux was markedly variable on a time scale of days, particularly during four days near optical maximum, when the X-rays became bright and soft. This strong X-ray variability continued for another month, after which the X-rays hardened as the optical flux declined. The UV flux was high throughout the outburst, consistent with quasi-steady shell burning on the white dwarf. Given that accretion disks around white dwarfs with shell burning do not generally produce detectable X-rays (due to Compton-cooling of the boundary layer), the X-rays probably originated via shocks in the ejecta. As the X-ray photo-electric absorption did not vary significantly, the X-ray variability may directly link to the properties of the shocked material. AG Peg's transition from a slow symbiotic nova (which drove the 1850 outburst) to a classical symbiotic star suggests that shell burning in at least some symbiotic stars is residual burning from prior novae.Comment: Accepted by MNRAS 23 June 2016. Manuscript submitted in original form 5 April 201

Phospholipins of blood

Quantitative micro-chemical analyses are described for the determination of glycerol and choline in biological material, particularly in lipin _mixtures. The methods have been applied, with a phosphorus determination, to specimens of phospholipins prepared from human blood. Attempts to evolve a direct kephalin determination are also described

Effects of drinking-water filtration on Cryptosporidium Seroepidemiology, Scotland

Continuous exposure to low levels of Cryptosporidium oocysts is associated with production of protective antibodies. We investigated prevalence of antibodies against the 27-kDa Cryptosporidium oocyst antigen among blood donors in 2 areas of Scotland supplied by drinking water from different sources with different filtration standards: Glasgow (not filtered) and Dundee (filtered). During 2006–2009, seroprevalence and risk factor data were collected; this period includes 2007, when enhanced filtration was introduced to the Glasgow supply. A serologic response to the 27-kDa antigen was found for ≈75% of donors in the 2 cohorts combined. Mixed regression modeling indicated a 32% step-change reduction in seroprevalence of antibodies against Cryptosporidium among persons in the Glasgow area, which was associated with introduction of enhanced filtration treatment. Removal of Cryptosporidium oocysts from water reduces the risk for waterborne exposure, sporadic infections, and outbreaks. Paradoxically, however, oocyst removal might lower immunity and increase the risk for infection from other sources

Swift J0525.6+2416 and IGR J04571+4527: two new hard X-ray selected magnetic cataclysmic variables identified with XMM-Newton

IGR J04571+4527 and Swift J0525.6+2416 are two hard X-ray sources detected in the Swift/BAT and INTEGRAL/IBIS surveys. They were proposed to be magnetic cataclysmic variables of the Intermediate Polar (IP) type, based on optical spectroscopy. IGR J04571+4527 also showed a 1218 s optical periodicity, suggestive of the rotational period of a white dwarf, further pointing towards an IP classification. We here present detailed X-ray (0.3-10 keV) timing and spectral analysis performed with XMM-Newton, complemented with hard X-ray coverage (15-70 keV) from Swift/BAT. These are the first high signal to noise observations in the soft X-ray domain for both sources, allowing us to identify the white dwarf X-ray spin period of Swift J0525.6+2416 (226.28 s), and IGR J04571+4527 (1222.6 s). A model consisting of multi-temperature optically thin emission with complex absorption adequately fits the broad-band spectrum of both sources. We estimate a white dwarf mass of about 1.1 and 1.0 solar masses for IGR J04571+4527 and Swift J0525.6+2416, respectively. The above characteristics allow us to unambiguously classify both sources as IPs, confirming the high incidence of this subclass among hard X-ray emitting Cataclysmic Variables.Comment: 8 pages, 4 figures, 3 tables. Accepted for publication in MNRA

Unmasking Microaggressions on the Homefront: Exploring Faculty and Staff Perceptions After Attending an Online Workshop on Microaggressions in Higher Education

Microaggressions are brief and everyday slights, insults, indignities, and denigrating messages sent to people of color and/or marginalized groups (women, LGBTQ+, etc.) by well-intentioned [people] who are unaware of the hidden messages being communicated (Sue et al., 2007). Microaggressions are connected to broader conceptualizations of the impact of implicit bias and systems of inequity. Specifically, in K-12 and higher education, microaggressions impact the physical, social, and emotional well-being of those who experience them. Growing research posits the need for more discussions in education about racism, sexism, and other bias prevalent in the field of education (Bergerson, 2003). As such, some researchers ((Escayg, 2018; Lin, Lake, & Rice, 2008) have advocated for the importance of bringing anti-bias pedagogy into educational spaces, which involves attempting to move beyond educators\u27 comfort zones and providing them with tangible strategies to disrupt microaggressive behaviors. To discuss the intent and impact of microaggressions in educational settings and how we might respond to them, we developed a two-hour online workshop for educators and students at Western State University. This workshop allowed participants to think critically about microaggressions, how they impact higher education, and how administrators, faculty, staff, and students can promote inclusive environments. The workshop included a presentation on microaggression theory, microaggression scenarios in education, and the utilization of the A.C.T.I.O.N framework (Chueng, Ganote, & Souza, 2016) as a tool to disrupt microaggressions. Participants provided feedback about their experiences from the workshop based on an electronic survey they were provided at the end of the workshop

KIC 10449976: discovery of an extreme-helium subdwarf in the Kepler field

Optical spectroscopy of the blue star KIC 10449976 shows that it is an extremely helium-rich subdwarf with effective temperature T=40000+/-300 K and surface gravity log g=5.3+/-0.1. Radial-velocity measurements over a five-day timescale show an upper variability limit of ~50+/-20 km/s. Kepler photometry of KIC 10449976 in both long and short cadence modes shows evidence for a periodic modulation on a timescale of ~3.9 days. We have examined the possibility that this modulation is not astrophysical but conclude it is most likely real. We discuss whether the modulation could be caused by a low-mass companion, by stellar pulsations, or by spots. The identification of any one of these as cause has important consequences for understanding the origin of helium-rich subdwarfs.Comment: Accepted by MNRA