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Measuring reliable ages for stars: calibration of the [c/n] chemical clock and the impact of atomic diffusion on abundance/age determination of main sequence turnoff stars
No full textIn Galactic archeology, astronomers want to understand how the Milky Way formed and evolved. To be able to “time-stamp” events in chronological order, we need a reliable method to age-date large numbers of stars. Currently, the most reliable method is ages coming from star clusters, but they are limited in location and number. A useful tool to expand age-dating capabilities is chemical clocks: chemical abundances that are linked to stellar ages. In our work, we use open and globular clusters to establish a calibration between [C/N] and age, covering a metallicity range of dex. With this improved calibration, we can determine ages for over 300,000 stars within the SDSS/APOGEE DR17 survey. While these chemical changes help us to estimate ages on the red giant branch, chemical changes can also hinder age estimations in other parts of the HR diagram. On the main sequence and near the turnoff, the surface abundances of a star change from a combination of gravitational settling and radiative acceleration working against it, a process known as atomic diffusion. In this case, the surface abundance is not an accurate prediction of the bulk abundances that determine the stellar age. Recent studies suggest that this effect is not negligible, and in fact the ages derived from isochrones can be overestimated by 10-20\% if atomic diffusion is not accounted for. We use SDSS/APOGEE DR17 to investigate atomic diffusion in the open clusters NGC 752 and Ruprecht 147 in order to constrain the variation of atomic diffusion signatures with age, and discuss how these results may affect the estimation of precise ages for subgiant stars
The effects of outdoor, unstructured play on muscular strength and neuromuscular control in children
No full textInactivity levels among children are climbing at alarming rates, leading to research focused on cardiovascular health. However, a less known but severely dangerous childhood inactivity effect is the lack of activities that produce muscular strength (MusS) development. Appropriate MusS during childhood decreases the chances of diabetes, obesity, cardiovascular disease, and cancer while increasing bone mineral density, healthy blood lipid profiles, insulin sensitivity, mental health and quality of life dimensions. Increases in MusS also create efficient neuromuscular control (NC), allowing the child to exhibit more powerful and efficient movements. Developing appropriate MusS during childhood leads to physical, neurological, physiological, and cognitive advantage, leading to healthier, active future adults. Therefore, this dissertation explored movements beneficial for MusS and NC development in childhood, testing measures for assessing MusS and NC among children, and exploring outdoor, unstructured play as a means of promoting healthy MusS and NC development naturally for all children
Neurodivergence and Theatrical Costuming: The Sensory Experience
No full textThe purpose of this project was to provide insight on the sensory experiences of neurodivergent actors in relation to theatrical costuming. I created a survey to get input from neurodiverse actors and used the responses to create a sample costume that demonstrated sensory-friendly techniques. The results showed that the vast majority of respondents experience sensory processing differences which affect the way they navigate the world. Most also felt that the comfort of their costume affected their ability to perform well and maintain their mental and physical health during performance. I described my research, design, and construction process and provided examples of my own experiences as a neurodivergent actor and costumer with sensory differences. Ultimately, I sought to bridge the gap of understanding between neurotypical and neurodivergent individuals in theatre on the sensory experiences of theatrical costuming and determine how we, as designers and costumers, can better understand and accommodate the sensory needs of neurodivergent performers
Mercury Contamination of Arctic Spiders and Insects
No full textMercury (Hg) is a contaminant of global concern because of its potential to biomagnify in food webs and cause adverse health effects in humans and wildlife. Mercury emitted in temperate and tropical regions can be transported to the Arctic where it is deposited across the landscape. After reaching aquatic systems, inorganic forms of Hg (IHg) can be methylated to the toxic and bioaccumulative form, methylmercury (MeHg). The High Arctic of Greenland comprises many low-lying aquatic ecosystems, primarily characterized by permafrost and snowmelt ponds and wetlands. Insects and their spider predators that live near these aquatic systems may accumulate concentrations of MeHg that pose a risk to insectivorous birds. The purpose of the present study was to assess Hg levels in Arctic insects and spiders from High Arctic aquatic systems. In summer 2022, 8,591 insects and 1,351 spiders were collected from eight locations in Northwest Greenland. Specimens were composited by collection site and taxa and analyzed for total Hg (IHg + MeHg). THg concentrations for all samples ranged from 57-1,100 µg/kg dry weight (dw), suggesting that some taxa had Hg concentrations that exceeded the previously published risk thresholds for insectivorous birds. This analysis will provide insight into the extent of mercury contamination in Arctic insects and spiders
Inappropriate Sinus Tachycardia: A Retrospective Analysis of a Single Center Large Cohort Yielding Novel Clinical Diagnostic Criteria
No full textResearch Question: Limited data currently exists to characterize and predict the clinical phenotype of inappropriate sinus tachycardia (IST), with few large cohort analyses available. To determine if any demographic or clinical history data may predict IST, we have designed this research to answer two specific questions: 1) Can we determine specific diagnostic criteria using Holter monitor data to identify patients suspected to have IST? and 2) Are there any consistent demographics or components of a patient¿s history that exist within this clinical cohort to help clinicians predict or identify diagnosis of IST in patients that fit the clinical picture?Background and Significance: Patients with IST reportedly have an unexplained upregulation of resting heart rate (HR) to over 100 beats per minute (bpm), with an average HR of at least 90 bpm over a 24-hour period. The tachycardia is often accompanied by distressing symptoms that can greatly impact patients¿ quality of life. IST is a diagnosis of exclusion, for patients with no discernable cause of secondary tachycardia. While literature surrounding clinical presentation and epidemiology is growing, there are currently few large cohort studies that have been performed to analyze trends in cardiac rhythm over time. Furthermore, a knowledge gap currently exists regarding the potential for patient history or demographics that could help predict or diagnose IST in patients with this presentation.Materials and Methods: This is a retrospective cohort chart review study in which patients found to meet the inclusion criteria for IST had their clinical documents reviewed and that data compiled. While the clinical cohort analyzed was over 500 patients, the study population of patients meeting inclusion and exclusion criteria was narrowed to 205 patients. Using the electronic medical record at Consultants in Cardiovascular Medicine and Science (CCMS), each patient identified to have the IST diagnosis had their Holter monitor results analyzed. Additionally, demographics and certain comorbidities were collected and analyzed as well.Results: Of the patients in the study cohort, 82% were female, with an average age of 49 and an average body mass index (BMI) of 30.4. For race and ethnicity, 82% of patients were White, 9% were Black, and 8% were Hispanic. For history and comorbidities, 24% had a history of tobacco use, 18% had diabetes, 28% had hyperlipidemia, and 44% had hypertension; 25% were being effectively treated with ivabradine. For Holter results, the mean average HR was 87 bpm, mean maximum HR was 146 bpm, mean minimum HR was 58 bpm, mean daytime HR was 93 bpm, mean nighttime HR was 83 bpm, mean % of time in sinus tachycardia was 22%, mean PVC burden was 0.55%, and mean PAC burden was 0.78%.Conclusion: This study confirms that IST mostly affects females and suggests that IST may affect middle-aged patients more commonly than previously reported. It found that obesity and common major comorbidities may be more prevalent in IST patients than other studies suggest. Our cohort results suggest that the upregulation of HR in IST patients may not be as dramatic as previously thought, which should lead future studies to reconsider the most popular diagnostic criteria for IST
Using represented bodies in Renaissance artworks to teach musculoskeletal and surface anatomy
No full textSurface anatomy is an important skill for students in preparation for patient care, and peer examination is often used to teach musculoskeletal and surface anatomy. An alternative pedagogical approach is to use bodies represented in artworks. Represented bodies display fictive anatomy, providing students with the opportunity to apply their musculoskeletal knowledge and to think critically when evaluating the anatomical fidelity of a represented body. An elective course at the University of Michigan enabled undergraduate students to analyze the musculoskeletal and surface anatomy depicted in Renaissance artworks. Students traveled to Italy in 2018 ( n ?=?14) and 2022 ( n ?=?15) to analyze the fictive anatomy portrayed in artistic sculptures and musculoskeletal structures depicted in wax anatomy models and sculpted skeletons. In assignments, students were asked to identify musculoskeletal structures as portrayed in the context of represented anatomy created by Italian Renaissance artists and to assess the fidelity of the depicted anatomy. The students also applied their knowledge of musculoskeletal anatomy to describe body position and evaluate muscle function in their assessments of the accuracy or inaccuracy of the fictive anatomy. The students reported that evaluating the anatomical fidelity of represented bodies in artworks supported their learning of musculoskeletal and surface anatomy, and that their critical thinking skills improved in the course. Evaluation of the anatomical fidelity of represented bodies in artworks is an effective pedagogical approach that can be implemented in art museums as an adjunctive learning experience to deepen students' musculoskeletal and surface anatomy knowledge and further develop their critical thinking skills
The Role of Intuition in Moral Epistemology
No full textThe aim of this paper is to argue that intuitionism is a plausible alternative to Utilitarianism and Kantianism as an ethical theory. It argues that common objections to intuitionism also undermine justification for both Utilitarianism and Kantianism, and neither ethical theory can justify itself except in reference to the sorts of intuition they claim to reject in intuitionism. The multiplicity of self-evident principles proposed by intuitionism should also not be assumed to be a weakness of intuitionism. It is plausibly preferable to both on a foundational and epistemic level to both discussed alternatives due to the coherence of its basic principles (which are mutually reinforcing and justifiable in a way that neither Kantianism or Utilitarianism's principles can be) and because a reasonable error theory exists to fix its mistakes (which both Kantianism and Utilitarianism lack).
The paper begins by introducing the basic framework of ethics and defining intuitionism. It disputes some common arguments against intuitions holding epistemic weight in ethics. A discussion of Utilitarianism and Kantianism follows which aims to show how each depends on intuition. The paper concludes with a discussion of the plausibility of error correction under each of these three normative theories, an argument that having multiple basic moral principles is not a fault of intuitionism, and a brief conclusion summarizing this paper's findings
Complex syntax in spoken and written language in children who are deaf or hard of hearing
No full textThe purpose of this study is to explore complex syntax in children who are deaf and hard of hearing (DHH) in comparison to their typical hearing peers through an analysis of spoken and written language samples. Participants in this study consist of children with typical hearing as well as children who are DHH with either hearing aids or cochlear implants. The children’s written complex syntax abilities were analyzed from language samples taken from standardized measures. Their spoken complex syntax abilities were analyzed from spontaneous language samples that were recorded, transcribed, and coded. The results of these indicate how complex syntax differs between groups as well as across mediums
NUTRITION AND COOKING KNOWLEDGE AND SELF-EFFICACY AMONG ADOLESCENTS ENROLLED IN A SUMMER COOKING CAMP
No full textBackground: Limited opportunities to gain knowledge regarding nutrition and food preparation techniques currently exist in the school system. Dietetic interns taught adolescents enrolled in a university-hosted summer cooking camp how to prepare foods from scratch, use basic knife skills, meal plan and combine common kitchen ingredients to make budget-friendly meals and healthy snacks. Dietetic students taught nutrition lessons about reading nutrition labels, protein, sodium, nutrient density, added sugars, whole grains, vitamin C and iron.
Objectives: 1) Describe cooking/nutrition knowledge and self-efficacy in adolescents; 2) describe the correlation between caregiver cooking/nutrition efficacy and adolescent cooking/nutrition knowledge prior to education.
Design: Following IRB approval, a convenience sample of 7th-9th grade adolescents enrolled in a five-day cooking camp and their caregivers were recruited to participate in the study.
Methods: Adolescent participants completed pre- and post-camp surveys to measure cooking/nutrition knowledge, experience and self-efficacy. One caregiver per adolescent completed a pre-camp survey to measure cooking experience and confidence. Frequency of family meals and home-meal preparation was measured for all participants.
Results: Adolescent participants (n=23) were 12.8+/-0.95 years. Participants were 74% (n=17) female and 26% (n=6) male. Caregiver confidence of cooking ability using basic ingredients and adolescent pre-camp cooking confidence (r=0.547, p=0.001) were positively correlated. Adolescent participants reported that they were able to perform the following tasks pre- and post-camp, respectively: Cook raw meat and poultry (52%, n=12; 96%, n=22); Cook dried beans (9%, n=2; 100%, n=23); Use food preparation methods to prevent food borne illness (52%, n=12; 96%, n=22); Shop for foods to stay on a budget (61%, n=14; 96%, n=22); Use the nutrition facts label (78%, n=18; 100%, n=23).
Conclusions: A cooking camp is an effective approach to provide adolescents with cooking/nutrition education and improve their self-efficacy related to meal preparation
DISRESPECTABILITY AND DEVIANCE: CONVERSATIONS ON BLACK QUEER GENDER AND BLACK COMMUNAL FUTURES
No full textMy work seeks to uplift Black Queer deviance and disrespectability, a disruption of social standards of respectability to unearth new possibilities of existing and being, casting these concepts as abolitionist praxis. I utilize alternative collection practices, like communal oral histories, and self-portraits of the individuals who make up a community to revisit the past, reclaim Black Queer Representation, and reimagine gender holistically through visual and embodied storytelling. I document and explore the lives and embodied knowledge of Black gender nonconforming and trans folks, as they live and thrive within the presumed fugitivity of the South. I attempt to address the lack of Southern Black Queer Trans Narratives by centering Black Trans and Queer Individuals narratives within my work, coupled with the visual aspects of my zine. By centralizing alternative methods and the stories of a neglected portion of the Black community demonstrates embracing the disrespectful as a re-orientation created by Black Trans Queer folks through disrespectability can reorient the understanding of our Black bodies within a Black communal context