81 research outputs found

    The balance of power: accretion and feedback in stellar mass black holes

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    In this review we discuss the population of stellar-mass black holes in our galaxy and beyond, which are the extreme endpoints of massive star evolution. In particular we focus on how we can attempt to balance the available accretion energy with feedback to the environment via radiation, jets and winds, considering also possible contributions to the energy balance from black hole spin and advection. We review quantitatively the methods which are used to estimate these quantities, regardless of the details of the astrophysics close to the black hole. Once these methods have been outlined, we work through an outburst of a black hole X-ray binary system, estimating the flow of mass and energy through the different accretion rates and states. While we focus on feedback from stellar mass black holes in X-ray binary systems, we also consider the applicability of what we have learned to supermassive black holes in active galactic nuclei. As an important control sample we also review the coupling between accretion and feedback in neutron stars, and show that it is very similar to that observed in black holes, which strongly constrains how much of the astrophysics of feedback can be unique to black holes.Comment: To be published in Haardt et al. Astrophysical Black Holes. Lecture Notes in Physics. Springer 201

    The Fueling and Evolution of AGN: Internal and External Triggers

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    In this chapter, I review the fueling and evolution of active galactic nuclei (AGN) under the influence of internal and external triggers, namely intrinsic properties of host galaxies (morphological or Hubble type, color, presence of bars and other non-axisymmetric features, etc) and external factors such as environment and interactions. The most daunting challenge in fueling AGN is arguably the angular momentum problem as even matter located at a radius of a few hundred pc must lose more than 99.99 % of its specific angular momentum before it is fit for consumption by a BH. I review mass accretion rates, angular momentum requirements, the effectiveness of different fueling mechanisms, and the growth and mass density of black BHs at different epochs. I discuss connections between the nuclear and larger-scale properties of AGN, both locally and at intermediate redshifts, outlining some recent results from the GEMS and GOODS HST surveys.Comment: Invited Review Chapter to appear in LNP Volume on "AGN Physics on All Scales", Chapter 6, in press. 40 pages, 12 figures. Typo in Eq 5 correcte

    The current status of species recognition and identification in Aspergillus

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    The species recognition and identification of aspergilli and their teleomorphs is discussed. A historical overview of the taxonomic concepts starting with the monograph of Raper & Fennell (1965) is given. A list of taxa described since 2000 is provided. Physiological characters, particularly growth rates and the production of extrolites, often show differences that reflect phylogenetic species boundaries and greater emphasis should be placed on extrolite profiles and growth characteristics in species descriptions. Multilocus sequence-based phylogenetic analyses have emerged as the primary tool for inferring phylogenetic species boundaries and relationships within subgenera and sections. A four locus DNA sequence study covering all major lineages in Aspergillus using genealogical concordance theory resulted in a species recognition system that agrees in part with phenotypic studies and reveals the presence of many undescribed species not resolved by phenotype. The use of as much data from as many sources as possible in making taxonomic decisions is advocated. For species identification, DNA barcoding uses a short genetic marker in an organism”s DNA to quickly and easily identify it to a particular species. Partial cytochrome oxidase subunit 1 sequences, which are used for barcoding animal species, were found to have limited value for species identification among black aspergilli. The various possibilities are discussed and at present partial β-tubulin or calmodulin are the most promising loci for Aspergillus identification. For characterising Aspergillus species one application would be to produce a multilocus phylogeny, with the goal of having a firm understanding of the evolutionary relationships among species across the entire genus. DNA chip technologies are discussed as possibilities for an accurate multilocus barcoding tool for the genus Aspergillus

    Tries and conversions: are sports sponsors pursuing the right objectives?

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    Sports sponsorship is perceived as important in developing relationships with key clients. However, few companies set relationship marketing objectives when sponsoring sports. This paper aims to examine whether sports sponsors are pursuing the right objectives. It concludes that a deeper understanding of the sponsor's relationship marketing objectives could heighten the sponsor's success, thereby reinforcing and sustaining their own relationship with the sponsoring organisation

    Track E Implementation Science, Health Systems and Economics

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138412/1/jia218443.pd

    Oxford MDM-2 magnetic spectrometer and particle hole states in calcium 40 in the region of excitation 7-12 MEV

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    LD:D50685/84 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

    Electronic medical records: recommendations for routine. Report of the eHID (Electronic Health Indicator Data Project): site visits to participating networks.

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    Aims: The electronic Health Indicator Data (eHID) project aims to investigate how routinely collected clinical data from electronic records in primary care can be used to determine health indicators across the European Union (EU). This presentation will present the findings of site visits to the various networks that are collecting and analysing data from electronic medical records, to examine current practice and to determine the strengths and weaknesses of each system in providing health indicator data. The findings from these visits will be used to assist in agreeing a protocol for measuring the four health indicators in the participating networks. Design and methods: observational study of recording practices in 7 European practice networks. Visits to the networks and participating GP practices in each country were conducted. Questionnaires were designed for network organizations and GPs. Results: The site visits provided an invaluable opportunity to gain insight into bridging the gap between recording arrangements and recording practice. Key lessons from these visits and the practical problems will be presented. Conclusions: From the information collected during these visits reliable and consistent data could be obtained from routine electronic medical records in the various networks, provided disciplined and consistent recording rules are observed

    Electronic medical records: recommendations for routine. Report of the eHID (Electronic Health Indicator Data Project): the eHID project recommendations.

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    Aims: eHID (electronic Health Indicator Data) is an EC sponsored project concerned with best practice in recording diagnostic data in routine ( as opposed to research specific) general practice electronic patient records. Design and methods: The project included investigation on site of recording routines within the practices, abstraction of selected data on disease incidence and prevalence, analysis after age based standardisation, interpretation of the results set within a framework of discussion among the participants reflecting the national differences in health care access and provision of services. Results: Eight practice based networks in seven countries participated over the period 2004-2007. All were able to provide incidence and prevalence data on diabetes and most also provided similar data on ischaemic heart disease which could be reasonably compared after due consideration of the healthcare systems from which they came. The provision of comparable data on mental illness presented more difficulties. The difficulties of making direct comparisons were identified and solutions to them derived from joint consideration of the data. The need for disciplined and consistent data capture is paramount. The optimum methods to achieve comparable data were formulated as recommendations which are presented for discussion in the workshop. Conclusions: Epidemiological comparisons can be made at international level using information collected in routine patient electronic medical records
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