14,485 research outputs found

    Evidence for Stellar Streaming in the Cores of Elliptical Galaxies: A Kinematic Signature of Mergers?

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    We present evidence for non-Gaussian velocity fields within the cores of luminous elliptical galaxies. This evidence is based upon high signal-to-noise, medium-resolution spectroscopy of the cores of early-type members of the Virgo and Coma clusters obtained with the WIYN 3.5-m telescope. The Virgo data were acquired using an integral-field unit (DensePak) allowing the velocity field to be sampled over a variety of spatial scales. The Coma data were obtained through single, 2-arcsec diameter fibers. The cross-correlation profiles of luminous ellipticals show considerable structure, often having several features with amplitudes as high as 10% that of the cross-correlation peak itself. This structure is most obvious within a radius of 1.5 arcsec (at Virgo), or < 100 pc, and is nearly undetectable when the data are binned over R < 15 arcsec, or < 1 kpc. Similar features are found in the single-fiber spectra of the luminous ellipticals in the Coma Cluster suggesting they are ubiquitous to giant ellipticals. Interesting, only the most luminous elliptical galaxies show this phenomena; the central regions of lower luminosity ellipticals have regular, Gaussian-like profiles. We interpret this kinematic structure as ``stellar streaming'' and suggest that this phenomena could be a relic signature of the merger history of luminous elliptical galaxies.Comment: Latex, 5 pages, 2 figure

    Connected to the Organization: A Survey of Communication Technologies in the Modern Organizational Landscape

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    In today’s organizations, traditional and cutting-edge technologies compete for increased usage. This exploratory project provides a snapshot of the communication technology (CT) landscape by examining the use of 25 different CTs and their relations to a variety of common demographic variables. Results suggest that, although newer CTs are in use today, more traditional and established CTs such as e-mail, Internet, telephones, and voicemail still dominate the landscape

    Determination of tungsten resonance absorption integrals by activation

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    Determination of tungsten resonance absorption integrals by activatio

    COPD: Optimizing Treatment

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    A guideline update and an expanded armamentarium have many physicians wondering how best to treat patients with COPD. Chronic obstructive pulmonary disease (COPD) carries a high disease burden. In 2012, it was the 4th leading cause of death worldwide.1,2 In 2015, the World Health Organization updated its Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines, classifying patients with COPD based on disease burden as determined by symptoms, airflow obstruction, and exacerbation history.3 These revisions, coupled with expanded therapeutic options within established classes of medications and new combination drugs to treat COPD (TABLE 1),3-6 have led to questions about interclass differences and the best treatment regimen for particular patients

    Examining the importance of Aberdeenshire (UK) coastal waters for North Sea bottlenose dolphins (Tursiops truncates)

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    Using land- and vessel-based surveys, data on the relative abundance, distribution and habitat use of bottlenose dolphins (Tursiops truncatus) in Aberdeenshire waters were collected between 1999 and 2001. Bottlenose dolphins were present throughout the year, with peak abundance during the months of March to May. The occurrence of calves was seasonal, With the proportion of calves highest during the spring months. Foraging behaviour was recorded mainly in the vicinity of Aberdeen harbour. Dolphins photographed in Aberdeenshire waters were successfully matched and confirmed as Moray Firth animals. The results of the present study suggest that Moray Firth bottlenose dolphins utilize Aberdeenshire waters more frequently than previously reported. Aberdeen harbour is apparently an important feeding area, and Aberdeenshire waters are regularly used by another-calf pairs. This has important management implications since this area of coastline does not currently form part of the designated Special Area of Conservation (SAC) for this population

    Exports and Environmental Responsibility: Applying NEPA to the Export-Import Bank

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