4353 research outputs found
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Seven Years of SN 2014C: A Multiwavelength Synthesis of an Extraordinary Supernova
Get PDFSN 2014C was originally classified as a Type Ib supernova, but at phase ϕ = 127 days, post-explosion strong Hα emission was observed. SN 2014C has since been observed in radio, infrared, optical and X-ray bands. Here we present new optical spectroscopic and photometric data spanning ϕ = 947–2494 days post-explosion. We address the evolution of the broadened Hα emission line, as well as broad [O iii] emission and other lines. We also conduct a parallel analysis of all publicly available multiwavelength data. From our spectra, we find a nearly constant Hα FWHM velocity width of ∼2000 km s−1 that is significantly lower than that of other broadened atomic transitions (∼3000–7000 km s−1) present in our spectra ([O i] λ6300; [O iii] λλ4959, 5007; He i λ7065; [Ca ii] λλ7291, 7324). The late radio data demand a fast forward shock (∼10,000 km s−1 at ϕ = 1700 days) in rarified matter that contrasts with the modest velocity of the Hα. We propose that the infrared flux originates from a toroidal-like structure of hydrogen surrounding the progenitor system, while later emission at other wavelengths (radio, X-ray) likely originates predominantly from the reverse shock in the ejecta and the forward shock in the quasi-spherical progenitor He-wind. We propose that the Hα emission arises in the boundary layer between the ejecta and torus. We also consider the possible roles of a pulsar and a binary companion
Mental Health and Quality of Life in Postmenopausal Women as a Function of Retrospective Menopause Symptom Severity
No full textObjectives: Perimenopause is commonly viewed as a window of vulnerability for developing psychiatric and eating disorders, especially for women who experience severe symptoms. However, menopausal symptoms may have a lasting effect on older women\u27s mental health and quality of life (QOL) into postmenopause. The current study examined older (60+) postmenopausal women\u27s mental health and QOL as a function of retrospective menopausal symptom severity.
Methods: Participants were recruited via public online postings and included 227 postmenopausal women, ages 60 to 94years old (M = 68.84, SD = 6.53). Participants completed an online questionnaire to assess past menopausal symptoms as well as current depression, anxiety, sleep difficulties, binge eating, QOL, and demographics. The relation between the retrospective severity of menopausal symptoms and mental health/QOL was evaluated using linear regressions, while controlling for demographic covariates.
Results: Retrospective menopause symptom severity was significantly associated with depression, sleep difficulties, binge eating severity, and most QOL measures. Regarding covariates, having a psychiatric history was significantly associated with all outcome variables, except for anxiety. Time since menopause and body mass index were significantly associated with binge eating severity. Regarding specific symptom subgroups, psychological and somato-vegetative symptoms were most associated with mental health and QOL.
Conclusion: The menopausal transition is a significant change in a woman\u27s life and the challenges of menopausal symptoms can have lasting impacts on women\u27s health. It is imperative that future research seeks to further understand the lasting impacts of this transition on the lives of older women to ensure proper interventions are implemented for successful aging
Bringing COSO to Life: Engaging Students with Real World Examples of Internal Controls Using Digital Storytelling
No full textThis study describes an assignment using digital storytelling to increase students’ understanding of internal controls and the Committee of Sponsoring Organization\u27s Internal Control-Integrated Framework (COSO). In this assignment, students interview local company representatives about examples of the company\u27s successes related to internal controls and develop digital stories to share the experience with the class. Digital storytelling incorporates audio, video, and music to convey information related to events or concepts in a way that allows for increased comprehension and memory recall. The assignment is designed to engage students with the material by learning from professionals and provide a fun and meaningful way to report on COSO real world examples. Survey responses reveal that the assignment increases engagement in the class by providing a way for students to learn experientially from professionals. This approach is easily translated to other courses in which real-world examples can increase student engagement and comprehension through an active learning experience
Quantitative Evaluation of the Roles of Ocean Chemistry and Climate on Ooid Size Across the Phanerozoic: Global versus Local Controls
No full textOoid size in natural systems can be predicted based on the expected equilibrium between precipitation and abrasion rates. Therefore, ooid size distributions may enable quantitative inferences about past ocean and climate conditions from sedimentology that complement insights from geochemistry. A few previous attempts have been made to compile information on ooid sizes across the Phanerozoic, but no systematic ooid size dataset is available and equilibrium models of ooid growth have not been explored comprehensively. In this study, convolutional neural network-based segmentation was used to automate ooid size measurement and provide a systematic sampling of ooid sizes spanning the Phanerozoic. This data set is coupled with Monte Carlo simulations to quantitatively explore the interplay between three testable physicochemical parameters (long-term average carbonate saturation state, bed shear velocity and intermittency of transport) in determining equilibrium ooid size. The numerical model shows that a typical-sized ooid (≤1000 µm) can grow under a wide range of parameter combinations whereas giant ooids (\u3e2000 µm) can only form under a more restricted set of circumstances. Furthermore, the model predicts that the formation of giant ooids is common when conditions favourable for rapid CaCO3 precipitation are achieved. This finding is consistent with the naturally rare occurrences of giant ooids, which developed under exceptional environmental conditions and are primarily associated with intervals of bimineralic seas and elevated sea-surface temperature (greenhouse or transitional climate). Whereas global controls could help explain secular trends in ooid size, significant spatial variability of ooid size in several time intervals further demonstrates the importance of local environmental parameters in the growth of ooids. Together, spatial and temporal variation in ooid size distributions can complement geochemical proxies in quantitatively reconstructing ancient tropical marine environments
Brazilian Indigenous Peoples: Territories, Legal Rights and The Obstacles of Structural and Institutional Racism
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Community Health Workers in Central-Southern Amazonia: An Ethnographic Account of the Munduruku People of Kwatá Laranjal Indigenous Land
Get PDFThis article analyzes the role of Munduruku indigenous community health workers (CHW) with the expansion of biomedical services as part of state presence and territorial control in Brazil. Centuries of interethnic contacts among the Munduruku have resulted in a plurality of health practices. Since 1999, Primary services have increased significantly, when the Indigenous Health System (SASI) was created. CHWs were incorporated as part of the health teams serving the indigenous lands. Munduruku CHWs have not only assumed an important role in the delivery of biomedical services, but also are key in the articulation between different traditions of care. Although there is a clash between the hegemony of biomedicine and the Mundurucu cosmographical perspective that links health to territory, the CHWs are protagonists and important actors in the negotiations and appropriations that occur in the contact zone of medical pluralism. They have emerged as local leaders, collaborating with village caciques in health service issues and dialoguing with and supporting families in therapeutic itineraries that include various medical traditions. In addition, they have become political actors in the new participatory spaces created for indigenous representation, such as local and district health councils that are part of the Indigenous Health System
