Characterizing young debris disks through far-infrared and optical observations

Circumstellar disks are the environments where extrasolar planets are born. Debris disks in particular are the last stage of circumstellar disk evolution, the youngest of which may harbor still-forming terrestrial planets. This dissertation focuses on examining the properties of dust grains in the youngest debris disks as a proxy to study the unseen parent planetesimal population that produces the dust in destructive collisions. The parent planetesimals are important to understanding the late stages of terrestrial planets because they can deliver volatile material, such as water, to young terrestrial planets. We used the Herschel Space Observatory to study young debris disks (ages 10-30 Myr) in the far-infrared where the thermal emission from the dust grains is brightest. We constructed spectral energy distributions (SEDs) of 24 debris disks and fit them with our debris disk models to constrain dust parameters such as temperature, dust location, and grain size. We also looked for correlations between the stellar and disk parameters and we found a trend between the disk temperature and stellar temperature, which we fit as a power-law. One bright, well studied disk in our sample, HD32297, has a well populated SED, allowing us to fit it with a more detailed model to determine dust grain composition. The HD32297 disk has also been imaged in scattered light, so we used the image to constrain the dust location before fitting the SED. We found the dust grains are composed of a highly porous and icy material, similar to cometary grains. This suggests there are icy comets in this system that could deliver water to any terrestrial planets in the disk. We followed up this system by observing it with the Hubble Space Telescope to get simultaneous spatial and spectral data of the disk. These data let us look for compositional changes with disk radius. We found the disk has a very red color at optical wavelengths in the innermost radius we probed (110 AU). This could indicate the presence of organic material, or it could be a property of the scattering phase function of large grains. Further analysis of this data is ongoing

Physiological Responses & Coping Strategies of Sensory Defensive Adults

Purpose: The purpose of this study was to learn how adults cope with their sensory defensiveness (SD) and how physiological responses differ between adults who self-report as high SD versus low SD. Methods: In this continuation study participants (age 18-64; n=23) were categorized as low SD (control group; n=9) or high SD (experimental group; n=14) via their Adolescent Adult Sensory Profile (AASP) scores and Sensory Response Questionnaire (SRQ) scores (Brown, & Dunn, 2002 & Wilbarger, 2009). The last nine participants also completed the Coping Strategies Questionnaire (CSQ). All participants partook in the sensory challenge protocol which examined their electrodermal activity (EDA) responses to auditory, tactile and olfactory stimuli. Discussion: Overall, high SD group had higher EDA responses, but not all were statistically significant. The high SD group had significantly higher EDA (p \u3c 0.1) responses when the nuk brush and lawnmower were administered. The CSQ results found mental preparation/talking through was the most frequently used coping strategy. There was a strong correlation between AASP & CSQ, but not statistically significant. Limitations: With a larger sample size, the results of higher EDA responses between the low and high SD groups could become statistically significant. Difficulty with recruiting participants who self-report as low SD could influence the overall outcome. Conclusion: Adults with high SD have higher physiological responses to sensory stimuli compared to adults with low SD and these adults utilize time consuming coping strategies frequently. Occupational therapists can facilitate a more targeted intervention for adults with SD

Optical Coronagraphic Spectroscopy of AU Mic: Evidence of Time Variable Colors?

We present coronagraphic long slit spectra of AU Mic's debris disk taken with the STIS instrument aboard the Hubble Space Telescope (HST). Our spectra are the first spatially resolved, scattered light spectra of the system's disk, which we detect at projected distances between approximately 10 and 45 AU. Our spectra cover a wavelength range between 5200 and 10200 angstroms. We find that the color of AU Mic's debris disk is bluest at small (12-35 AU) projected separations. These results both confirm and quantify the findings qualitatively noted by Krist et al. (2005), and are different than IR observations that suggested a uniform blue or gray color as a function of projected separation in this region of the disk. Unlike previous literature that reported the color of AU Mic's disk became increasingly more blue as a function of projected separation beyond approximately 30 AU, we find the disk's optical color between 35-45 AU to be uniformly blue on the southeast side of the disk and decreasingly blue on the northwest side. We note that this apparent change in disk color at larger projected separations coincides with several fast, outward moving "features" that are passing through this region of the southeast side of the disk. We speculate that these phenomenon might be related, and that the fast moving features could be changing the localized distribution of sub-micron sized grains as they pass by, thereby reducing the blue color of the disk in the process. We encourage follow-up optical spectroscopic observations of the AU Mic to both confirm this result, and search for further modifications of the disk color caused by additional fast moving features propagating through the disk.Comment: Accepted by AJ, 13 pages, 8 figures, 1 tabl

Weaving Indigenous and Western Science Knowledges Through a Land-Based Field Course at Bkejwanong Territory (Laurentian Great Lakes)

In response to a growing interest in building Indigenous-led educational experiences, we codeveloped a land-based field course that wove Indigenous ways of knowing together with Western ecological concepts. The spirit of the course was the one rooted in varied ways of knowing nature, on the land, the water, and the culture—to see the Great Lakes from an Anishinaabe perspective. Situated in the heart of the Laurentian Great Lakes Basin at Bkejwanong Territory (Walpole Island First Nation), in the Traditional Territory of the Three Fires Confederacy of First Nations (Ojibwe, Odawa, and Potawatomi) on Turtle Island (North America), this inaugural undergraduate university course was led by an Indigenous instructor with contributions from non-Indigenous science faculty from the university and local community knowledge keepers. Here, we describe our journey in cocreating land-based teaching modules with Indigenous scholars and scholars at the University of Windsor, Ontario, Canada. We focused on experiences that exposed students to traditional ways of knowing nature, and reflections were used as the main teaching pedagogy. The course offered daily perspectives and activities across land and water and examined dimensions of biodiversity as sacred beings and medicine. Outcomes and indicators of success were driven by the individual’s reflection and evaluation on their own growth, as expressed through a final project aimed at bridging knowledges, supporting community initiatives or both. This case is designed to offer an example that has potential for application to many other contexts where community-faculty partnerships and land-based learning opportunities are availabl

Comparing and Contrasting a Program versus System Approach to Evaluation: The Example of a Cardiac Care System

This paper focuses on the application of systems thinking concepts to evaluate systems.  The terms systems and systems thinking concepts are first defined.  The use of systems thinking concepts in program and system evaluation are then highlighted.  It is noted that while there are methods available to assist evaluation practitioners in applying systems thinking concepts to program evaluation, there is a need for similar guidance in applying systems thinking concepts to evaluating systems.  System Evaluation Theory (SET) is then reviewed as one evaluation theory designed to apply systems thinking concepts to evaluating systems. A case illustration is presented to help teach practitioners how to apply SET’s three steps.  The discussion focuses on comparing the differences between evaluation questions answered by applying systems thinking concepts versus those using program logic models

HORIZON Center: Promoting Health and Health Equity in Inner Boston

The HORIZON Center is an Exploratory Center of Excellence (COE) funded by a grant from the National Institute on Minority Health and Health Disparities (NIMHD). Our mission is to improve minority health and promote health equity through research, research training, and community engagement. Like other COEs, HORIZON is organized into four core areas: research, research training, community engagement, and administration. However, we work to promote collaboration and integration across core areas

Positive Organisational Psychology 2.0: Embracing The Technological Revolution

Positive Organisational Psychology (POP) has experienced significant growth in the past two decades, contributing to our understanding of work-related well-being and performance. However, the discipline is now on the cusp of a new wave of research and innovation that may reshape its discourse. This paper introduces the concept of ‘Positive Organisational Psychology 2.0’ (POP 2.0) as an evidence-based, data-driven field that utilizes technological advancements and human-centred design to understand and enhance positive characteristics of individuals, organisations, and society for optimal psychological functioning, wellbeing, and performance. The paper begins with an overview of POP’s emergence, highlighting its key characteristics and exploring the factors behind its rapid growth and declining relevance. We then conceptualize POP 2.0, outline its defining features, and advocate for a broader scope, expanded focal audience, enhanced methodologies, and transformative role shifts for practitioners. We conclude by outlining opportunities, challenges and perspectives for the next wave of innovative research