38,597 research outputs found
Discovery of an expanding molecular bubble in Orion BN/KL
During their infancy, stars are well known to expel matter violently in the
form of well-defined, collimated outflows. A fairly unique exception is found
in the Orion BN/KL star-forming region where a poorly collimated and somewhat
disordered outflow composed of numerous elongated ``finger-like'' structures
was discovered more than 30 years ago. In this letter, we report the discovery
in the same region of an even more atypical outflow phenomenon. Using
CO(2-1) line observations made with the Submillimeter Array (SMA), we
have identified there a 500 to 1,000 years old, expanding, roughly spherically
symmetric bubble whose characteristics are entirely different from those of
known outflows associated with young stellar objects. The center of the bubble
coincides with the initial position of a now defunct massive multiple stellar
system suspected to have disintegrated 500 years ago, and with the center of
symmetry of the system of molecular fingers surrounding the Kleinmann-Low
nebula. We hypothesize that the bubble is made up of gas and dust that used to
be part of the circumstellar material associated with the decayed multiple
system. The Orion hot core, recently proposed to be the result of the impact of
a shock wave onto a massive dense core, is located toward the south-east
quadrant of the bubble. The supersonic expansion of the bubble, and/or the
impact of some low-velocity filaments provide a natural explanation for its
origin.Comment: Accepted to ApJ
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Personal Disability Identity Measurement: Self-Worth and Personal Meaning
In this study, I examined validity evidence for a new disability identity scale, Personal Disability Identity Scale–Self-Worth and Meaning, in a sample of 525 adults with visual impairment (VI) or blindness. Personal disability identity (PDI) refers to feelings about having a disability as well as incorporation of disability status into overall self-concept (Dunn & Burcaw, 2013). Pre-existing measures of PDI (Darling & Heckert, 2010; Hahn & Belt, 2004) operationalize three factors of the PDI concept (i.e., Affirmation, Denial, Pride), which has been theorized to encompass more domains (Dunn & Burcaw, 2013; Forber-Pratt, Lyew, Samples, & Mueller, 2017). The Self-Worth and Meaning subscales were intended to capture previously unexplored PDI domains, including self-worth as a person with a disability (Putnam, 2005) and personal meaning found in the experience of disability (Dunn & Burcaw, 2013). Exploratory and confirmatory factor analyses supported the structural validity of Self-Worth and Meaning scores as well as an overarching four-factor structure of PDI scores composed of Pride/Affirmation, Acceptance (versus Denial), Self-Worth, and Positive Personal Meaning (i.e., Meaning). Correlational analyses between Self-Worth, Meaning, and existing PDI measures supported the convergent and divergent validity of Self-Worth and Meaning scores. Further correlational analyses between Self-Worth and Meaning subscales and indicators of well-being (i.e., satisfaction with life, anxiety/depression) offered support for the external validity of Self-Worth and Meaning. This dissertation contributes to the literature on disability identity by offering an expanded empirical model of PDI as well as a new PDI measure that is derived from models of disability identity that had not been explored empirically (Dunn & Burcaw, 2013; Putnam, 2005)
A Framing Analysis of Latinos in the Facebook Pages of News Organizations
This study of the Facebook pages of six legacy media organizations extended framing theory to apply to social media. In the study of 557 articles, four new frames and 10 new subframes were identified. The immigration frame and its two subframes, deportation and undocumented, dominated the coverage of Latinos during the period of the study. The politics frame was the second most dominant frame. This study updated the old data and found that no progress has been made, with the exception of a lesser use of the criminal frame. This improvement could be because the study included six months of the presidential campaign. However, Latinos were still framed as Others and as an oppressed community. This study concluded that there was no significant difference between the way legacy TV networks and legacy newspapers covered Latinos
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