7,159 research outputs found
Getting research findings into practice : when to act on the evidence.
There is increasing interest in providing evidence based health care—that is, care in which healthcare professionals, provider managers, those who commission health care, the public, and policymakers consistently consider research evidence when making decisions. Purchasers, for example, should be able to influence the organisation and delivery of care (such as for cancer and stroke services) and the type and content of services (such as using chiropractic for back pain or dilatation and curettage and drug treatment for menorrhagia). Policymakers should ensure that policies on treatment reflect and are consistent with research evidence, and that the incentive structure within the health system promotes cost effective practice. They must also ensure that there is an adequate infrastructure for monitoring changes in practice and for producing, gathering, summarising, and disseminating evidence. Clinicians determine the day to day care patients receive in healthcare systems, and user groups (for example, patients, their families, and their representatives) are also beginning to play an important role in influencing healthcare decisions
Head-up transition behavior of pilots with and without head-up display in simulated low-visibility approaches
To quantify head-up transition behavior with and without a flightpath type head-up display, eight rated B-727 pilots each flew 31 manual and coupled approaches in a simulator with B-727 dynamics and collimated model board external scene. Data were also obtained on the roll played by the head-up display in the coupled-to-manual transition. Various wind shears, low visibilities, and ceilings were tested along with unexpected misalignment between the runway and head-up display symbology. The symbolic format used was a conformal scene. Every pilot except one stayed head-up, flying with the display after descending below the ceiling. Without the display and as altitude decreased, the number of lookups from the instrument panel decreased and the duration of each one increased. No large differences in mean number or duration of transitions up or down were found during the head-up display runs comparing the no-misalignment with the lateral instrument landing system offset misalignment runs. The head-up display led to fewer transitions after the pilot made a decision to land or execute a missed approach. Without the display, pilots generally waited until they had descended below the ceiling to look outside the first time, but with it several pilots looked down at their panel at relatively high altitudes (if they looked down at all). Manual takeover of control was rapid and smooth both with and without the display which permitted smoother engine power changes
Fatty-acid uptake in prostate cancer cells using dynamic microfluidic raman technology
It is known that intake of dietary fatty acid (FA) is strongly correlated with prostate cancer progression but is highly dependent on the type of FAs. High levels of palmitic acid (PA) or arachidonic acid (AA) can stimulate the progression of cancer. In this study, a unique experimental set-up consisting of a Raman microscope, coupled with a commercial shear-flow microfluidic system is used to monitor fatty acid uptake by prostate cancer (PC-3) cells in real-time at the single cell level. Uptake of deuterated PA, deuterated AA, and the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were monitored using this new system, while complementary flow cytometry experiments using Nile red staining, were also conducted for the validation of the cellular lipid uptake. Using this novel experimental system, we show that DHA and EPA have inhibitory effects on the uptake of PA and AA by PC-3 cells
Anatomy, morphology and evolution of the patella in squamate lizards and tuatara (Sphenodon punctatus)
The patella (kneecap) is the largest and best-known of the sesamoid bones, postulated to confer biomechanical advantages including increasing joint leverage and reinforcing the tendon against compression. It has evolved several times independently in amniotes, but despite apparently widespread occurrence in lizards, the patella remains poorly characterised in this group and is, as yet, completely undescribed in their nearest extant relative Sphenodon (Rhynchocephalia). Through radiography, osteological and fossil studies we examined patellar presence in diverse lizard and lepidosauromorph taxa, and using computed tomography, dissection and histology we investigated in greater depth the anatomy and morphology of the patella in 16 lizard species and 19 Sphenodon specimens. We have found the first unambiguous evidence of a mineralised patella in Sphenodon, which appears similar to the patella of lizards and shares several gross and microscopic anatomical features. Although there may be a common mature morphology, the squamate patella exhibits a great deal of variability in development (whether from a cartilage anlage or not, and in the number of mineralised centres) and composition (bone, mineralised cartilage or fibrotendinous tissue). Unlike in mammals and birds, the patella in certain lizards and Sphenodon appears to be a polymorphic trait. We have also explored the evolution of the patella through ancestral state reconstruction, finding that the patella is ancestral for lizards and possibly Lepidosauria as a whole. Clear evidence of the patella in rhynchocephalian or stem lepidosaurian fossil taxa would clarify the evolutionary origin(s) of the patella, but due to the small size of this bone and the opportunity for degradation or loss we could not definitively conclude presence or absence in the fossils examined. The pattern of evolution in lepidosaurs is unclear but our data suggest that the emergence of this sesamoid may be related to the evolution of secondary ossification centres and/or changes in knee joint conformation, where enhancement of extensor muscle leverage would be more beneficial.Sophie Regnault, Marc E. H. Jones, Andrew A. Pitsillides, John R. Hutchinso
LoCuSS: The steady decline and slow quenching of star formation in cluster galaxies over the last four billion years
We present an analysis of the levels and evolution of star formation activity
in a representative sample of 30 massive galaxy clusters at 0.15<z<0.30 from
the Local Cluster Substructure Survey (LoCuSS), combining wide-field Spitzer
24um data with extensive spectroscopy of cluster members. The specific-SFRs of
massive (M>10^10 M_sun) star-forming cluster galaxies within r200 are found to
be systematically 28% lower than their counterparts in the field at fixed
stellar mass and redshift, a difference significant at the 8.7-sigma level.
This is the unambiguous signature of star formation in most (and possibly all)
massive star-forming galaxies being slowly quenched upon accretion into massive
clusters, their SFRs declining exponentially on quenching time-scales in the
range 0.7-2.0 Gyr. We measure the mid-infrared Butcher-Oemler effect over the
redshift range 0.0-0.4, finding rapid evolution in the fraction (f_SF) of
massive (M_K3M_sun/yr, of the
form f_SF (1+z)^7.6. We dissect the origins of the Butcher-Oemler effect,
revealing it to be due to the combination of a ~3x decline in the mean
specific-SFRs of star-forming cluster galaxies since z~0.3 with a ~1.5x
decrease in number density. Two-thirds of this reduction in the specific-SFRs
of star-forming cluster galaxies is due to the steady cosmic decline in the
specific-SFRs among those field galaxies accreted into the clusters. The
remaining one-third reflects an accelerated decline in the star formation
activity of galaxies within clusters. The slow quenching of star-formation in
cluster galaxies is consistent with a gradual shut down of star formation in
infalling spiral galaxies as they interact with the intra-cluster medium via
ram-pressure stripping or starvation mechanisms. We find no evidence for the
build-up of cluster S0 bulges via major nuclear star-burst episodes.Comment: 24 pages, 12 figures. Accepted for publication in Ap
Cosmic dance in the Shapley Concentration Core - I. A study of the radio emission of the BCGs and tailed radio galaxies
The Shapley Concentration () covers several degrees in the
Southern Hemisphere, and includes galaxy clusters in advanced evolutionary
stage, groups of clusters in the early stages of merger, fairly massive
clusters with ongoing accretion activity, and smaller groups located in
filaments in the regions between the main clusters. With the goal to
investigate the role of cluster mergers and accretion on the radio galaxy
population, we performed a multi-wavelength study of the BCGs and of the
galaxies showing extended radio emission in the cluster complexes of Abell 3528
and Abell 3558. Our study is based on a sample of 12 galaxies. We observed the
clusters with the GMRT at 235, 325 and 610 MHz, and with the VLA at 8.46 GHz.
We complemented our study with the TGSS at 150 MHz, the SUMSS at 843 MHz and
ATCA at 1380, 1400, 2380, and 4790 MHz data. Optical imaging with ESO-VST and
mid-IR coverage with WISE are also available for the host galaxies. We found
deep differences in the properties of the radio emission of the BCGs in the two
cluster complexes. The BCGs in the A3528 complex and in A3556, which are
relaxed cool-core objects, are powerful active radio galaxies. They also
present hints of restarted activity. On the contrary, the BCGs in A3558 and
A3562, which are well known merging systems, are very faint, or quiet, in the
radio band. The optical and IR properties of the galaxies are fairly similar in
the two complexes, showing all passive red galaxies. Our study shows remarkable
differences in the radio properties of the BGCs, which we relate to the
different dynamical state of the host cluster. On the contrary, the lack of
changes between such different environments in the optical band suggests that
the dynamical state of galaxy clusters does not affect the optical counterparts
of the radio galaxies, at least over the life-time of the radio emission.Comment: 24 pages, 11 figures, accepted for publication in Astronomy &
Astrophysic
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Serving GODAE Data and Products to the Ocean Community
The Global Ocean Data Assimilation Experiment (GODAE [http://
www.godae.org]) has spanned a decade of rapid technological development. The ever-increasing volume and diversity of oceanographic data produced by in situ instruments, remote-sensing platforms, and computer simulations have driven
the development of a number of innovative technologies that are essential for connecting scientists with the data that they need. This paper gives an overview of the technologies that have been developed and applied in the course of GODAE, which now provide users of oceanographic data with the capability to discover, evaluate, visualize, download, and analyze data from all over the world. The key to this
capability is the ability to reduce the inherent complexity of oceanographic data by providing a consistent, harmonized view of the various data products. The challenges of data serving have been addressed over the last 10 years through the cooperative skills and energies of many individuals
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