Emission from Very Small Grains and PAH Molecules in Monte Carlo Radiation Transfer Codes: Application to the Edge-On Disk of Gomez's Hamburger

We have modeled optical to far infrared images, photometry, and spectroscopy of the object known as Gomez's Hamburger. We reproduce the images and spectrum with an edge-on disk of mass 0.3M_sun and radius 1600AU, surrounding an A0 III star at a distance of 280pc. Our mass estimate is in excellent agreement with recent CO observations. However, our distance determination is more than an order of magnitude smaller than previous analyses which inaccurately interpreted the optical spectrum. To accurately model the infrared spectrum we have extended our Monte Carlo radiation transfer codes to include emission from polycyclic aromatic hydrocarbon (PAH) molecules and very small grains (VSG). We do this using pre-computed PAH/VSG emissivity files for a wide range of values of the mean intensity of the exciting radiation field. When Monte Carlo energy packets are absorbed by PAHs/VSGs we reprocess them to other wavelengths by sampling from the emissivity files, thus simulating the absorption and re-emission process without reproducing lengthy computations of statistical equilibrium, excitation and de-excitation in the complex many level molecules. Using emissivity lookup tables in our Monte Carlo codes gives the flexibility to use the latest grain physics calculations of PAH/VSG emissivity and opacity that are being continually updated in the light of higher resolution infrared spectra. We find our approach gives a good representation of the observed PAH spectrum from the disk of Gomez's Hamburger. Our models also indicate the PAHs/VSGs in the disk have a larger scaleheight than larger radiative equilibrium grains, providing evidence for dust coagulation and settling to the midplane.Comment: ApJ accepte

Serum cholesterol: A Superior Prognostic Marker of Sepsis Mortality in the ICU Compared to Procalcitonin or C-reactive Protein

Background: Sepsis is the fourth most common admitting diagnosis to the ICU and the second leading cause of death. Despite aggressive management, sepsis continues to have a high mortality rate as high as 48.8% and costs an estimated $366 million annually. The need for an early prognostic marker to identify those at highest risk for mortality in order to optimize therapeutics is critical. Procalcitonin (PCT) and C-reactive protein (CRP) are the current standard markers in the ICU setting; however, each test carries significant limitations. Cholesterol may be a useful prognostic marker of sepsis given that lipid metabolism is significantly altered by systemic inflammation. These changes have been noted to occur within hours of an inflammatory state and are negatively correlated to clinical outcome. Few studies have evaluated the efficacy of serum cholesterol compared to PCT and CRP to identify those at high risk for mortality in the ICU. Can total cholesterol be a superior prognostic marker of mortality in patients admitted to the ICU for sepsis compared to the current gold standard of PCT or CRP? Methods: An exhaustive search was conducted using MEDLINE-Ovid, Web of Science, and CINAHL using the following keywords: cholesterol, procalcitonin or C-reactive protein, and sepsis. Relevant articles were assessed for quality using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE). A search on the National Institute of Health (NIH) clinical trials inquiry site indicates that there are no current trials in any phase evaluating serum cholesterol as a prognostic marker in ICU septic patients. Results: Two studies met eligibility criteria and were included in this systematic review. A prospective observational trial with 106 participants demonstrated a statistically significant superiority of total cholesterol as a prognostic marker for septic ICU patients with infection only compared to PCT and CRP. A second prospective observational trial with 96 participants demonstrated no superior benefit of total cholesterol levels when compared to CRP but total cholesterol had statistically significant utility in predicting mortality separately. Conclusion: Total cholesterol may be a useful and superior prognostic marker of mortality for patients admitted to the ICU with sepsis secondary to infection compared to its CRP and PCT counterparts. Serum cholesterol could provide ICU clinicians a more sensitive screening tool for identifying those patients at highest risk for morbidity and mortality irrespective of other underlying comorbidities, whereas CRP may be more useful for monitoring response to therapy. Cholesterol pathophysiology may also yield insight on experimental therapy including the use of statin medications in septic patients in the ICU

The Count of Saint-Gilles and the Saints of the Apocalypse: Occitanian Piety and Culture in the Time of the First Crusade

This dissertation examines Raymond of Saint-Gilles’ regional affiliation in Occitania (modern southern France) and the effect of that identity on his conduct of the First Crusade. Crusade historiography has not paid much attention to regional difference, but Raymond’s case shows that Occitanians approached crusading in a fundamentally different manner from other crusaders. They placed apocalyptic eschatology in the forefront of the First Crusade and portraying the First Crusade as bringing about the New Jerusalem. To be Occitanian was not merely to be a speaker of Occitan. It was to be part of a Mediterranean culture, halfway between classical Roman and medieval Frank, with a religious culture influenced by Greek saints, Egyptian monasticism, an intellectually and culturally vigorous Jewish population, and repeated Arab invasions and pirate raids. It was also to be imbued with romanitas, a close connection to Rome, to both the Papacy and the material, legal, and cultural legacy of the Roman Empire. At the same time, Raymond was not the only important figure to go on the First Crusade from Occitania. The papal legate, Adhemar of Le Puy, came from the Auvergne, a radically different region where the reaction to the collapse of the Carolingian empire led to a region ruled by the clergy, supported by idol-like statues of saints and organized through the Peace of God. These two disparate identities came together in the First Crusade, a Gregorian Reformist venture conceived and organized with Occitanian leadership. This team, the new Moses and Aaron of the crusaders, effectively followed papal policy in the early stages of the crusade. With the traumatic siege of Antioch and the “discovery” of the Holy Lance, however, a radical shift in the crusade occurred, following the eschatological visions of a handful of Occitanian priests. Though the Kingdom of God did not, in the end, appear, the apocalyptic eschatology that the Occitanians brought with them on the First Crusade led to Raymond of Saint-Gilles refusing the crown of Jerusalem, preferring to leave empty-handed than risk becoming the Antichrist

Rates and Drivers of Nitrate Uptake in Fluvial Wetlands in Urbanizing, Coastal Watersheds

Humans have had a substantial impact on the global nitrogen cycle, releasing large amounts of reactive nitrogen to the landscape. Watersheds have been found to remove substantial quantities of this anthropogenic nitrogen, with aquatic networks preventing much of it from reaching the coast. Within these aquatic networks, channelized streams have been studied extensively. However, in many coastal watersheds, fluvial wetlands are a large component of the aquatic network yet have not been studied as broadly as channelized reaches. As fluvial wetlands are also likely to have a sizeable impact on river network-scale nitrogen removal, a greater understanding of their effect on nitrogen cycling is necessary. We developed a new approach for quantifying fluvial wetland nitrate uptake measured at the whole ecosystem scale, using a method conceived in channelized reaches, in conjunction with new in situ sensor technology. Using this new approach, we found ambient uptake velocities in fluvial wetlands that ranged from -170.6 to 1220.0 m yr-1. These uptake velocities were generally higher than those found for channelized reaches within the same watersheds and in a similar range as uptake velocities found for fluvial wetland surface transient storage patches. Neither gross primary productivity nor ecosystem respiration exerted strong control on uptake rates, however, both discharge and detention time were significantly related to nitrate uptake. The effects of biology and hydrology on nitrate removal were then tested using a reach-scale numeric model. Hydrology was found to have a greater impact on nitrate removal compared to biology however, the cumulative effect of both hydrology and biology had the greatest impact. This is important because the watersheds draining suburban Boston, MA are experiencing ongoing urbanization, leading to greater inputs of anthropogenic nitrogen to the landscape. The beaver population is concurrently experiencing a resurgence, leading to an increase in the number of fluvial wetlands within these watersheds and with it, a greater potential for nitrogen removal. As such, fluvial wetlands may be able to offset the increase in nitrogen loading, preventing additional nitrogen from reaching the coast

Converting threats into opportunities predicting medical error reporting behavior.

Medical errors are a public health epidemic and a major threat to patient safety. Estimates suggest they may be responsible for 210,000 - 440,000 preventable deaths per year. This would make medical errors the third leading cause of death in the United States. The societal burden of medical errors is steep, with the economic impact near $1 trillion. The purpose of this study was to use a theory-driven approach to better understand the reporting behavior of healthcare professional. Increased error reporting leads to heightened awareness of the precursors or conditions generating errors, which can then be corrected. In its most simplistic view, reporting is tool used towards the prevention of medical errors. A health care marketing firm was hired to recruit 106 health care professionals to complete a survey on their intention to report medical errors. Random and anonymous sampling techniques were employed to help mitigate the risk associated with answering questions that may be risky and lead to social desirability bias. Regression model statistics were statistically significant in explaining 53.3% of the variance in intention scores, R2 = .533, F(8, 69) = 9.86, p β = .537, p = .001), perceived behavioral control (β = .594, p = .002), and actual behavioral control (β = 1.25, p = .005), contributed significantly to the model statistics. Psychological safety was not a significant predictor of intention. These findings suggest psychological safety may be redundant with the theory’s existing predictors, working through one or more of the theory constructs. Developing novel strategies for improving the reporting behavior of health care providers, targeting behavioral attitude and perceived behavioral control, will be essential in safeguarding the health of the public through the reduction of medical errors

Research to Practice: Multiple Perspectives on Implementing the Rehabilitation Act Amendments of 1992

This summary of a qualitative study reports the results of focus groups with administrators and counselors in Massachusetts\u27s vocational rehabilitation agency. The findings highlight differences in perspectives on how the 1992 Rehabilitation Act Amendments have been implemented

Content Analysis: U.S. Newspaper and social media portrayal of President Obama in association with the killing of Osama bin Laden during the 2012 presidential election year

In a broad sense, public relations is the communication between an organization and its audience. Public relations helps create and maintain a relationship between the two. When an organization experiences a success or failure public relations is put into place to help rally public support. The intent of this thesis aims to determine the tone of President Obama in U.S. newspapers and social media in association with the capturing and killing of terrorist Osama bin Laden. This thesis examines a variety of U.S. newspapers by region and social media. Newspaper articles related to the topic were retrieved from six regional newspapers: Columbus Dispatch, Houston Chronicle, Charlotte Observer, New York Times, Los Angeles Times, and Washington Post. From these papers, a specific time period was chosen to examine articles. The months of April, June, and August 2012 were chosen. During these months, a keyword search for “osama bin laden” was used. Articles that contained this keyword were then examined and coded. Blogs and Facebook pages of the Republican and Democratic Party were examined. Two political blogs, Daily Kos and Red State, were chosen. From these blogs and Facebook pages, the same time period was chosen as for the newspapers. The keyword search was also the same, “osama bin laden”

Exploring the Links Between Seasonal Variation and Spider Foraging

According to optimal foraging theory, generalist predators, such as spiders, are thought to feed indiscriminately on prey according to its availability, especially when food is scarce. In contrast, generalists can display selective feeding decisions under regimes of high prey abundance, but few studies have tracked changes in prey choice on a seasonal basis under open field conditions. Additionally, adaptations to surviving winter have been largely ignored in the research of foraging behavior. To elucidate this, I monitored prey availability and collected common forest-dwelling wolf spiders for molecular gut-content analysis, in parallel for 18 months, to assess the temporal changes occurring in spider preferences of common leaf litter prey. In addition, to determine if any physiological improvements to resisting low temperature mortality were affecting spider foraging, I also collected spiders monthly to track changes in spider supercooling points. The results revealed that spiders do exhibit selective feeding throughout the year, and appear to do so in a way that diversifies their diets. Also, despite low litter temperatures putting them in severe freezing risk, cold tolerance in these spiders remained unchanged throughout the winter, which suggests opportunity for growth during this uncompetitive period is paramount to accumulating survivorship-increasing, but also mobility-decreasing, cryoprotectants

Interpreting Spectral Energy Distributions from Young Stellar Objects. I. A grid of 200,000 YSO model SEDs

We present a grid of radiation transfer models of axisymmetric young stellar objects (YSOs), covering a wide range of stellar masses (from 0.1Msun to 50Msun) and evolutionary stages (from the early envelope infall stage to the late disk-only stage). The grid consists of 20,000 YSO models, with spectral energy distributions (SEDs) and polarization spectra computed at ten viewing angles for each model, resulting in a total of 200,000 SEDs. [...]. These models are publicly available on a dedicated WWW server: http://www.astro.wisc.edu/protostars/ . In this paper we summarize the main features of our models, as well as the range of parameters explored. [...]. We examine the dependence of the spectral indices of the model SEDs on envelope accretion rate and disk mass. In addition, we show variations of spectral indices with stellar temperature, disk inner radius, and disk flaring power for a subset of disk-only models. We also examine how changing the wavelength range of data used to calculate spectral indices affects their values. We show sample color-color plots of the entire grid as well as simulated clusters at various distances with typical {\it Spitzer Space Telescope} sensitivities. We find that young embedded sources generally occupy a large region of color-color space due to inclination and stellar temperature effects. Disk sources occupy a smaller region of color-color space, but overlap substantially with the region occupied by embedded sources, especially in the near- and mid-IR. We identify regions in color-color space where our models indicate that only sources at a given evolutionary stage should lie. [...].Comment: 69 pages, 28 figures, Accepted for publication in ApJS. Preprint with full resolution figures available at http://www.astro.wisc.edu/protostars