1,202 research outputs found
Building Grounded Theory with Social Media Data
The growing popularity and constant innovations of social media platforms and applications have transformed ways of interacting, working, creating value and innovating. We elaborate upon how building theory from case studies may be adapted to the opportunities and challenges of social media environments. We delve into key challenges of the research process: case study design, data analysis, and engaging in multi methods
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Evaluation of outreach services for primary care and mental health; assessing the impact
Objectives: This paper reports an evaluation, carried out for London Health Libraries, of the impact of outreach services to primary care and mental health workers in thirteen different settings. The main aims of the project were to identify the impact being made by the service, and to produce best practice guidelines for outreach services in this kind of ‘difficult’ community setting.
Methods: Methods used were: analysis of documents (all 13 services); analysis of any evaluation already performed by or for the service (all 13 services); interviews with outreach librarians (11 services); questionnaire survey of a representative sample of users (8 services, with 66 returned questionnaires, 35% response rate). The services evaluated were very diverse, in terms of setting, structure, functions and activities, and extent and nature of self-evaluation and reporting. The evaluation was therefore largely qualitative, in order to deal with the lack of a consistent ‘template’ for analysis. Emphasis was placed on trying to identify critical incidents , where it could be shown unambiguously that the outreach services made a difference to practice.
Study limitations included the difficulty of summarising and comparing very different situations and diverse services, difficulty in identifying critical incidents, and an inability to study ‘non-users’.
Findings: Service recipients felt better informed, more up-
to-date, more aware of resources, more confident and supported in their work, and saved time. Services contributed to a richer information environment. Direct impacts, demonstrably improved patient care, cost savings etc., were more difficult to establish
Impact of bovine oocyte maturation media on oocyte transcript levels, blastocyst development, cell number, and apoptosis.
The objectives were 1) to investigate the effects of oocyte maturation in serum-free and amino acid-supplemented defined media on oocyte transcript levels, blastocyst cell number, and apoptosis; 2) to investigate the influence of oocyte maturation culture atmosphere on blastocyst development, total cell number, and apoptosis; and 3) to examine the influence of epidermal growth factor (EGF) during oocyte maturation on blastocyst cell number and apoptosis. The results demonstrate that blastocysts derived from in vitro maturation, fertilization, and embryo culture protocols undergo apoptosis but that apoptotic levels are not greatly influenced by the oocyte maturation environment. Amino acid supplementation of oocyte maturation media was associated with enhanced developmental frequencies, increased blastocyst cell number, and elevated oocyte maternal mRNA levels. Oocyte maturation with supplemented synthetic oviduct fluid medium (cSOFMaa) resulted in blastocyst cell numbers comparable to those observed with Tissue Culture Medium 199 + newborn calf serum. Blastocyst development was reduced following oocyte maturation under a 5% CO(2), 7% O(2), 88% N(2) culture atmosphere. EGF supplementation of oocyte maturation medium resulted in a concentration-dependent increase in blastocyst development but did not influence blastocyst total cell number or apoptosis. Our findings indicate that cSOFMaa medium is an effective base medium for bovine oocyte maturation
X-ray and radio observations of central black holes in nearby low-mass early-type galaxies: Preliminary evidence for low Eddington fractions
We present new radio and X-ray observations of two nearby ( Mpc)
low-mass early-type galaxies with dynamically-confirmed central black holes:
NGC 5102 and NGC 205. NGC 5102 shows a weak nuclear X-ray source and has no
core radio emission. However, for the first time we demonstrate that it shows
luminous extended radio continuum emission in low-resolution, low-frequency ( GHz) data, consistent with jet lobes on scales pc formed from
past accretion and jet activity. By contrast, in new, extremely deep,
strictly-simultaneous Very Large Array and Chandra observations, no radio or
X-ray emission is detected from the black hole in NGC 205. We consider these
measurements and upper limits in the context of the few other low-mass
early-type galaxies with dynamically-confirmed black holes, and show that the
mean ratio of bolometric to Eddington luminosity in this sample is only
. These Eddington
ratios are lower than typical in a comparison sample of more massive early-type
galaxies, though this conclusion is quite tentative due to our small sample of
low-mass galaxies and potential biases in the comparison sample. This
preliminary result is in mild tension with previous work using less sensitive
observations of more distant galaxies, which predict higher X-ray luminosities
than we observe for low-mass galaxies. If it is confirmed that central black
holes in low-mass galaxies typically have low Eddington ratios, this presents a
challenge to measuring the occupation fraction of central black holes with
standard optical emission line, X-ray, or radio surveys.Comment: 13 pages, 4 figures, 3 tables. Accepted for publication in Ap
CO bandhead emission of massive young stellar objects: determining disc properties
Massive stars play an important role in many areas of astrophysics, but numerous details regarding their formation remain unclear. In this paper we present and analyse high-resolution (R~30 000) near-infrared 2.3 μm spectra of 20 massive young stellar objects (MYSOs) from the Red MSX Source (RMS) data base, in the largest such study of CO first overtone bandhead emission to date. We fit the emission under the assumption it originates from a circumstellar disc in Keplerian rotation. We explore three approaches to modelling the physical conditions within the disc-a disc heated mainly via irradiation from the central star, a disc heated mainly via viscosity, and a disc in which the temperature and density are described analytically. We find that the models described by heating mechanisms are inappropriate because they do not provide good fits to the CO emission spectra. We therefore restrict our analysis to the analytic model, and obtain good fits to all objects that possess sufficiently strong CO emission, suggesting circumstellar discs are the source of this emission. On average, the temperature and density structure of the discs correspond to geometrically thin discs, spread across a wide range of inclinations. Essentially all the discs are located within the dust sublimation radius, providing strong evidence that the CO emission originates close to the central protostar, on astronomical unit scales. In addition, we show that the objects in our sample appear no different to the general population of MYSOs in the RMS data base, based on their near- and mid-infrared colours. The combination of observations of a large sample of MYSOs with CO bandhead emission and our detailed modelling provide compelling evidence of the presence of small-scale gaseous discs around such objects, supporting the scenario in which massive stars form via disc accretion. © 2013 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society
The Milky Way Project: A statistical study of massive star formation associated with infrared bubbles
The Milky Way Project citizen science initiative recently increased the
number of known infrared bubbles in the inner Galactic plane by an order of
magnitude compared to previous studies. We present a detailed statistical
analysis of this dataset with the Red MSX Source catalog of massive young
stellar sources to investigate the association of these bubbles with massive
star formation. We particularly address the question of massive triggered star
formation near infrared bubbles. We find a strong positional correlation of
massive young stellar objects (MYSOs) and H II regions with Milky Way Project
bubbles at separations of < 2 bubble radii. As bubble sizes increase, a
statistically significant overdensity of massive young sources emerges in the
region of the bubble rims, possibly indicating the occurrence of triggered star
formation. Based on numbers of bubble-associated RMS sources we find that
67+/-3% of MYSOs and (ultra)compact H II regions appear associated with a
bubble. We estimate that approximately 22+/-2% of massive young stars may have
formed as a result of feedback from expanding H II regions. Using MYSO-bubble
correlations, we serendipitously recovered the location of the recently
discovered massive cluster Mercer 81, suggesting the potential of such analyses
for discovery of heavily extincted distant clusters.Comment: 16 pages, 17 figures. Accepted for publication in ApJ, comments
welcome. Milky Way Project public data release available at
http://www.milkywayproject.org/dat
Spin Reorientations Induced by Morphology Changes in Fe/Ag(001)
By means of magneto-optical Kerr effect we observe spin reorientations from
in-plane to out-of-plane and vice versa upon annealing thin Fe films on Ag(001)
at increasing temperatures. Scanning tunneling microscopy images of the
different Fe films are used to quantify the surface roughness. The observed
spin reorientations can be explained with the experimentally acquired roughness
parameters by taking into account the effect of roughness on both the magnetic
dipolar and the magnetocrystalline anisotropy.Comment: 4 pages with 3 EPS figure
Factors associated with self-care activities among adults in the United Kingdom: a systematic review
Background: The Government has promoted self-care. Our aim was to review evidence about who uses self-tests and other self-care activities (over-the-counter medicine, private sector,complementary and alternative medicine (CAM), home blood pressure monitors).
Methods: During April 2007, relevant bibliographic databases (Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, Applied Social Sciences Index and Abstracts, PsycINFO,British Nursing Index, Allied and Complementary Medicine Database, Sociological Abstracts,
International Bibliography of the Social Sciences, Arthritis and Complementary Medicine Database,
Complementary and Alternative Medicine and Pain Database) were searched, and potentially relevant studies were reviewed against eligibility criteria. Studies were included if they were published during the last 15 years and identified factors, reasons or characteristics associated with a relevant activity among UK adults. Two independent reviewers used proformas to assess the
quality of eligible studies.
Results: 206 potentially relevant papers were identified, 157 were excluded, and 49 papers related to 46 studies were included: 37 studies were, or used data from questionnaire surveys, 36 had quality scores of five or more out of 10, and 27 were about CAM. Available evidence suggests that
users of CAM and over-the-counter medicine are female, middle-aged, affluent and/or educated with some measure of poor health, and that people who use the private sector are affluent and/or educated.
Conclusion: People who engage in these activities are likely to be affluent. Targeted promotion may, therefore, be needed to ensure that use is equitable. People who use some activities also appear to have poorer measures of health than non-users or people attending conventional
services. It is, therefore, also important to ensure that self-care is not used as a second choice for people who have not had their needs met by conventional service
Detection of a glitch in the pulsar J1709-4429
We report the detection of a glitch event in the pulsar J17094429 (also
known as B170644) during regular monitoring observations with the Molonglo
Observatory Synthesis Telescope (UTMOST). The glitch was found during timing
operations, in which we regularly observe over 400 pulsars with up to daily
cadence, while commensally searching for Rotating Radio Transients, pulsars,
and FRBs. With a fractional size of ,
the glitch reported here is by far the smallest known for this pulsar,
attesting to the efficacy of glitch searches with high cadence using UTMOST.Comment: 3 pages, 1 figur
The Politics of Commerce : The Congress of Chambers of Commerce of the Empire, 1886-1914
Peer reviewedPublisher PD
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