55,183 research outputs found
Measuring attendance: issues and implications for estimating the impact of free-to-view sports events
A feature of many non-elite sports events, especially those conducted in public places is that they are free-to-view. The article focuses on the methodological issue of estimating spectator attendance at free-to-view events and the consequences of this for impact evaluation. Using empirical data from three case studies, the article outlines various approaches to measuring attendance and discusses the key issues and implications for evaluating free-to-view sports events in the future
Knowledge development for organic systems: An example of weed management
Despite the large amount information on weed biology and specific weed control measures produced by researchers, organic farmers still prioritise weeds as an important area for further research. A recent project investigating weed management in organic farming systems has established that knowledge and learning are key requirements for this to be effective. Development of relevant, practically useful knowledge depends on access to information generated ‘scientifically’ by researchers and also to knowledge generated as a result of farmer experience with weeds. This requires that farmers, advisors and researchers take a participatory approach to collecting and processing information on weed management, using it to develop new and relevant knowledge. The appropriate framework for knowledge development is thus a collegiate one in which all stakeholders’ value and learn from the observations and experience of others. These findings have implications for the way in which research is conducted and funded
New Cosmological Structures on Medium Angular Scales Detected with the Tenerife Experiments
We present observations at 10 and 15 GHz taken with the Tenerife experiments
in a band of the sky at Dec.=+35 degrees. These experiments are sensitive to
multipoles in the range l=10-30. The sensitivity per beam is 56 and 20 microK
for the 10 and the 15 GHz data, respectively. After subtraction of the
prediction of known radio-sources, the analysis of the data at 15 GHz at high
Galactic latitude shows the presence of a signal with amplitude Delta Trms ~ 32
microK. In the case of a Harrison-Zeldovich spectrum for the primordial
fluctuations, a likelihood analysis shows that this signal corresponds to a
quadrupole amplitude Q_rms-ps=20.1+7.1-5.4 microK, in agreement with our
previous results at Dec.+=40 degrees and with the results of the COBE DMR.
There is clear evidence for the presence of individual features in the RA range
190 degrees to 250 degrees with a peak to peak amplitude of ~110 microK. A
preliminary comparison between our results and COBE DMR predictions for the
Tenerife experiments clearly indicates the presence of individual features
common to both. The constancy in amplitude over such a large range in frequency
(10-90 GHz) is strongly indicative of an intrinsic cosmological origin for
these structures.Comment: ApJ Letters accepted, 13 pages Latex (uses AASTEX) and 4 encapsulated
postscript figures
FliPer: Checking the reliability of global seismic parameters from automatic pipelines
Our understanding of stars through asteroseismic data analysis is limited by
our ability to take advantage of the huge amount of observed stars provided by
space missions such as CoRoT, Kepler, K2, and soon TESS and PLATO. Global
seismic pipelines provide global stellar parameters such as mass and radius
using the mean seismic parameters, as well as the effective temperature. These
pipelines are commonly used automatically on thousands of stars observed by K2
for 3 months (and soon TESS for at least around 1 month). However, pipelines
are not immune from misidentifying noise peaks and stellar oscillations.
Therefore, new validation techniques are required to assess the quality of
these results. We present a new metric called FliPer (Flicker in Power), which
takes into account the average variability at all measured time scales. The
proper calibration of FliPer enables us to obtain good estimations of global
stellar parameters such as surface gravity that are robust against the
influence of noise peaks and hence are an excellent way to find faults in
asteroseismic pipelines.Comment: 4 pages, 3 figures, Proceedings for SF2A 2017 (Paris
Recommended from our members
Migrant workers in the East Midlands labour market 2010
This report is an update of previous intelligence (Migrant Workers in the East Midlands Labour Market 2007) on the profile and economic impact of migrant labour in the East Midlands economy
Microvesicles as vehicles for tissue regeneration: Changing of the guards
Purpose of Review:
Microvesicles (MVs) have been recognised as mediators of stem cell function, enabling and guiding their regenerative effects.
Recent Findings:
MVs constitute one unique size class of extracellular vesicles (EVs) directly shed from the cell plasma membrane. They facilitate cell-to-cell communication via intercellular transfer of proteins, mRNA and microRNA (miRNA). MVs derived from stem cells, or stem cell regulatory cell types, have proven roles in tissue regeneration and repair processes. Their role in the maintenance of healthy tissue function throughout the life course and thus in age related health span remains to be elucidated.
Summary:
Understanding the biogenesis and mechanisms of action of MVs may enable the development of cell-free therapeutics capable of assisting in tissue maintenance and repair for a variety of age-related degenerative diseases. This review critically evaluates recent work published in this area and highlights important new findings demonstrating the use of MVs in tissue regeneration
Early-type Galaxies in the Cluster Abell 2390 at z=0.23
To examine the evolution of the early-type galaxy population in the rich
cluster Abell 2390 at z=0.23 we have gained spectroscopic data of 51 elliptical
and lenticular galaxies with MOSCA at the 3.5 m telescope on Calar Alto
Observatory. This investigation spans both a broad range in luminosity
(-19.3>M_B>-22.3) and uses a wide field of view of 10'x10', therefore the
environmental dependence of different formation scenarios can be analysed in
detail as a function of radius from the cluster centre. Here we present results
on the surface brightness modelling of galaxies where morphological and
structural information is available in the F814W filter aboard the Hubble Space
Telescope (HST) and investigate for this subsample the evolution of the
Fundamental Plane.Comment: 5 pages, 5 figures, to appear in "Carnegie Observatories Astrophysics
Series, Vol. 3: Clusters of Galaxies: Probes of Cosmological Structure and
Galaxy Evolution", ed. J. S. Mulchaey, A. Dressler, and A. Oemler (Pasadena:
Carnegie Observatories,
http://www.ociw.edu/ociw/symposia/series/symposium3/proceedings.html
The Tenerife Cosmic Microwave Background Maps: Observations and First Analysis
The results of the Tenerife Cosmic Microwave Background (CMB) experiments are
presented. These observations cover 5000 and 6500 square degrees on the sky at
10 and 15 GHz respectively centred around Dec.~ +35 degrees. The experiments
are sensitive to multipoles l=10-30 which corresponds to the Sachs-Wolfe
plateau of the CMB power spectra. The sensitivity of the results are ~31 and
\~12 microK at 10 and 15 GHz respectively in a beam-size region (5 degrees
FWHM). The data at 15 GHz show clear detection of structure at high Galactic
latitude; the results at 10 GHz are compatible with these, but at lower
significance. A likelihood analysis of the 10 and 15 GHz data at high Galactic
latitude, assuming a flat CMB band power spectra gives a signal Delta
T_l=30+10-8 microK (68 % C.L.). Including the possible contaminating effect due
to the diffuse Galactic component, the CMB signal is Delta T_l=30+15-11 microK.
These values are highly stable against the Galactic cut chosen. Assuming a
Harrison-Zeldovich spectrum for the primordial fluctuations, the above values
imply an expected quadrupole Q_RMS-PS=20+10-7 microK which confirms previous
results from these experiments, and which are compatible with the COBE DMR.Comment: 17 pages, 7 figures. Submitted to Ap
- …