1,109 research outputs found

    Highly Ionised Gas as a Diagnostic of the Inner NLR

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    The spectra of AGN from the ultraviolet to the near infrared, exhibit emission lines covering a wide range of ionisation states, from neutral species such as [O I] 6300A, up to [Fe XIV] 5303A. Here we report on some recent studies of the properties of highly ionised lines (HILs), plus two case studies of individual objects. Future IFU observations at high spatial and good spectral resolution, will probe the excitation and kinematics of the gas in the zone between the extended NLR and unresolved BLR. Multi-component SED fitting can be used to link the source of photoionisation with the strengths and ratios of the HILs.Comment: Proceedings of the IAU Symposium: Co-evolution of Central Black Holes and Galaxie

    Optimizing Social Media in Humanitarian Crisis Responses

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    The social media boom has brought about a new age of communications and connectedness in our world. Just as the advent of televised news brought more attention to humanitarianism, social media has the capability to alter how humanitarian responses are viewed, coordinated, and executed. However, despite the vast potential of social media, humanitarian actors have been hesitant to fully incorporate it within their modus operandi. This essay explores the reasons for their skepticism and looks at cases where social media was put to good use during humanitarian crises. Using that information, we will argue that several measures can be taken to improve social media use in humanitarian responses: the creation of a social media data aggregation website, the inclusion of local actors in forming communications strategies, and the continued research of social media data trends in humanitarian crises. These measures would facilitate advocacy, aid distribution, and the ability to carry out the humanitarian imperative more effectively

    Workplace Factors Affecting the Delivery of Occupational Therapy Services: Perspectives of Occupational Therapy Practitioners

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    This research is a study on the occupation of being an occupational therapy practitioner. The work-related factors of focus are change, absenteeism, productivity/performance expectations, and work-stress and have the potential to influence the delivery of occupational therapy services in healthcare settings. Collective case-study inquiry and analysis was used to determine the overall meaning of the perspectives of 21 hospital, skilled nursing, outpatient, and community-based participants who were occupational therapists or occupational therapy assistants. Interviews and transcription took place, with a validation review. NVIVO-10 Qualitative Software was used to aid in the analysis and coding of the a-priori factors using deductive reasoning, followed by the derivation of themes, and the determination of the meaning of the perspectives of occupational therapy practitioners regarding the work-related factors. The results yielded information about how occupational therapy practitioners identified work related factors impacting optimal service delivery. Change factors related to the challenges of the duties performed by occupational therapy practitioners had to do with client’s clinical conditions, scheduling, insurance-related limitations, and coverage during periods of co-worker absence. Change factors were viewed as stressful, challenging, anxiety provoking, and constant. Absenteeism factors yielded results primarily related to communication. Productivity related responses were split between knowing and being affected, and not knowing and not being affected by performance expectations. Perceptions of worker stress depended on the day and other work-related factors. This research project communicated the rich findings of the occupational therapy participants’ perspectives about work-related factors and explored the participant meanings of their experiences related them

    The Lesson of Strategy: A Case Analysis of An E-Commerce Commercial Food Services Equipment Retailer

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    Literature on strategy is reviewed and applied directly in comparison to an e-Commerce company in the South Florida area. Practical managerial implications are discussed and laid out in an easy to follow format which provides insight to entrepreneurs and business leaders who are in need of a greater understanding of strategy. A comprehensive review of the company\u27s current strategies, industry position, internal and external forces, GAP analysis, and plans for action preempt a conclusion that puts it all together; a conclusion which has led the company towards significantly greater financial and operational success

    Shuttle S-band high gain switched beam breadboard antennas

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    The final fabrication and assembly of the S-band five-element, eight-beam breadboard antennas developed for the Space Shuttle program are described. Data summary sheets from component and final assembly testing are presented

    SS/FM telemetry system study Final report, Jul. 1965 - Feb. 1968

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    Engineering specifications and prototype model of SS/DSB multiplexe

    Modeling the connection between ultraviolet and infrared galaxy populations across cosmic times

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    Using a phenomenological approach, we self-consistently model the redshift evolution of the ultraviolet (UV) and infrared (IR) luminosity functions across cosmic time, as well as a range of observed IR properties of UV-selected galaxy population. This model is an extension of the 2SFM (2 star-formation modes) formalism, which is based on the observed "main-sequence" of star-forming galaxies, i.e. a strong correlation between their stellar mass and their star formation rate (SFR), and a secondary population of starbursts with an excess of star formation. The balance between the UV light from young, massive stars and the dust-reprocessed IR emission is modeled following the empirical relation between the attenuation (IRX for IR excess hereafter) and the stellar mass, assuming a scatter of 0.4\,dex around this relation. We obtain a good overall agreement with the measurements of the IR luminosity function up to z~3 and the UV luminosity functions up to z~6, and show that a scatter on the IRX-M relation is mandatory to reproduce these observables. We also naturally reproduce the observed, flat relation between the mean IRX and the UV luminosity at LUV>109.5 L⊙. Finally, we perform predictions of the UV properties and detectability of IR-selected samples and the vice versa, and discuss the results in the context of the UV-rest-frame and sub-millimeter surveys of the next decade

    An enhanced fraction of starbursting galaxies among high Eddington ratio AGNs

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    We investigate the star-forming properties of 1620 X-ray selected active galactic nuclei (AGN) host galaxies as a function of their specific X-ray luminosity (i.e. X-ray luminosity per unit host stellar mass) – a proxy of the Eddington ratio. Our motivation is to determine whether there is any evidence of a suppression of star formation at high Eddington ratios, which may hint towards ‘AGN feedback’ effects. Star formation rates (SFRs) are derived from fits to Herschel-measured far-infrared spectral energy distributions, taking into account any contamination from the AGN. Herschel-undetected AGNs are included via stacking analyses to provide average SFRs in bins of redshift and specific X-ray luminosity (spanning 0.01≲LX/M∗≲100L⊙M−1. After normalizing for the effects of mass and redshift arising from the evolving galaxy main sequence, we find that the SFRs of high specific luminosity AGNs are slightly enhanced compared to their lower specific luminosity counterparts. This suggests that the SFR distribution of AGN hosts changes with specific X-ray luminosity, a result reinforced by our finding of a significantly higher fraction of starbursting hosts among high specific luminosity AGNs compared to that of the general star-forming galaxy population (i.e. 8–10 per cent versus 3 per cent). Contrary to our original motivation, our findings suggest that high specific luminosity AGNs are more likely to reside in galaxies with enhanced levels of star formation
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