12,693 research outputs found
Global Entrepreneurship Monitor United Kingdom: 2007 Executive Report
This monitoring report compares Global Entrepreneurship Monitor (GEM) measures of entrepreneurial activity in the UK with participating G7 countries and the large industrialised or industrialising countries of Brazil, Russia, India and China ("BRIC"). It also summarises entrepreneurial activity within Government Office Regions of the UK
Antimatter production in supernova remnants
We calculate the energy spectra of cosmic rays (CR) and their secondaries
produced in a supernova remnant (SNR), taking into account the time-dependence
of the SNR shock. We model the trajectories of charged particles as a random
walk with a prescribed diffusion coefficient, accelerating the particles at
each shock crossing. Secondary production by CRs colliding with gas is included
as a Monte Carlo process. We find that SNRs produce less antimatter than
suggested previously: The positron/electron ratio and the antiproton/proton
ratio are a few percent and few , respectively. Moreover, the
obtained positron/electron ratio decreases with energy, while the
antiproton/proton ratio rises at most by a factor of two above 10 GeV.Comment: 8 pages, 8 eps figures; extended version of arXiv:1004.1118; v2:
minor corrections, matches published versio
Antimatter spectra from a time-dependent modeling of supernova remnants
We calculate the energy spectra of cosmic rays (CR) and their secondaries
produced in a supernova remnant (SNR), taking into account the time-dependence
of the SNR shock. We model the trajectories of charged particles as a random
walk with a prescribed diffusioncoefficient, accelerating the particles at each
shock crossing. Secondary production by CRs colliding with gas is included as a
Monte Carlo process. We find that SNRs produce less antimatter than suggested
previously: The positron/electron ratio and the antiproton/proton ratio are a
few percent and few , respectively. Both ratios do not rise
with energy.Comment: 4 pages, 4 eps figures; v2: results for time-dependent magnetic field
adde
What are the communication skills and needs of doctors when communicating a poor prognosis to patients and their families? A qualitative study from South Africa
Background. Thousands of South Africans are diagnosed with life-threatening illness every year. Research shows that, globally, of the 20 million people who need palliative care at the end of life every year, <10% receive it.Objectives. To explore communication skills and practices of medical practitioners when conveying a poor prognosis to patients and families, and to identify their communication skills, needs and understanding of palliative care.Methods. This was an exploratory qualitative study of practising doctors, using a grounded theory approach. The study was conducted at a government-funded public hospital in Cape Town, South Africa, which is a referral centre for various illnesses, including cancer. Face-toface, one-on-one interviews using a semistructured interview guide were conducted, using audio recording.Results. The emerging theory from this study is that doctors who understand the principles of palliative care and who have an established working relationship with a palliative care team feel supported and express low levels of emotional anxiety when conveying a poor prognosis.Conclusion. Having hospital-based palliative care teams in all public hospitals will provide support for patients and doctors handling difficult conversations. All healthcare professionals should be trained in palliative care so that they can effectively communicate concerns related to poor prognosis with patients and their families. Communication, loss and grief issues should be part of the curriculum in all disciplines and throughout training in medical school
Resistance of superconducting nanowires connected to normal metal leads
We study experimentally the low temperature resistance of superconducting
nanowires connected to normal metal reservoirs. We find that a substantial
fraction of the nanowires is resistive, down to the lowest temperature
measured, indicative of an intrinsic boundary resistance due to the
Andreev-conversion of normal current to supercurrent. The results are
successfully analyzed in terms of the kinetic equations for diffusive
superconductors
Correlation between X-ray Lightcurve Shape and Radio Arrival Time in the Vela Pulsar
We report the results of simultaneous observations of the Vela pulsar in
X-rays and radio from the RXTE satellite and the Mount Pleasant Radio
Observatory in Tasmania. We sought correlations between the Vela's X-ray
emission and radio arrival times on a pulse by pulse basis. At a confidence
level of 99.8% we have found significantly higher flux density in Vela's main
X-ray peak during radio pulses that arrived early. This excess flux shifts to
the 'trough' following the 2nd X-ray peak during radio pulses that arrive
later. Our results suggest that the mechanism producing the radio pulses is
intimately connected to the mechanism producing X-rays. Current models using
resonant absorption of radio emission in the outer magnetosphere as a cause of
the X-ray emission are explored as a possible explanation for the correlation.Comment: 6 pages, 5 figures, accepted by Ap
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