1,075 research outputs found
Patient access to voice prostheses and heat and moisture exchangers: Factors influencing physician's prescription and reimbursement in eight European countries
Quantum State Tomography of Complex Multimode Fields using Array Detectors
We demonstrate that it is possible to use the balanced homodyning with array
detectors to measure the quantum state of correlated two-mode signal field. We
show the applicability of the method to fields with complex mode functions,
thus generalizing the work of Beck (Phys. Rev. Letts. 84, 5748 (2000)) in
several important ways. We further establish that, under suitable conditions,
array detector measurements from one of the two outputs is sufficient to
determine the quantum state of signals. We show the power of the method by
reconstructing a truncated Perelomov state which exhibits complicated structure
in the joint probability density for the quadratures.Comment: 14 pages text and 3 figures. To be submitted to PR
Study protocol of a prospective multicenter study comparing (cost-)effectiveness of a tailored interdisciplinary head and neck rehabilitation program to usual supportive care for patients treated with concomitant chemo- or bioradiotherapy
Robustness of nonclassical superpositions states against decoherence
We make a comparative study of quadrature squeezing, photon-number
distribution and Wigner function in a decayed quantum system. Specifically, for
a field mode prepared initially in cat states interacting with a
zero-temperature environment, we show that the rate of reduction of the
nonclassical effects in this system is proportional to the occurrence of the
decoherence process.Comment: 11 pages, 4 figure
Textbook outcome as a composite outcome measure in non-small-cell lung cancer surgery
OBJECTIVES: Quality assessment is an important element in providing surgical cancer care. The main objective of this study was to develop a new composite measure 'textbook outcome', to evaluate and improve quality of surgical care for patients undergoing a resection for non-small-cell lung cancer (NSCLC).METHODS: All patients undergoing an anatomical resection for NSCLC from 2012 to 2016 registered in the nationwide Dutch Lung Cancer Audit were included in an analysis to assess usefulness of a composite measure as a quality indicator. Based on expert opinion, textbook outcome was defined as having a complete resection (negative resection margins and sufficient lymph node dissection), plus no 30-day or in-hospital mortality, no reintervention in 30days, no readmission to the intensive care unit, no prolonged hospital stay (<14days), no hospital readmission after discharge and no major complications. The percentage of patients with a textbook outcome was calculated per hospital. Between-hospital variation in textbook outcome was analysed using case-mix adjustment models.RESULTS: In total, 5513 patients were included in this study. Textbook outcome was achieved in 26.4% of patients. Insufficient lymph node dissection had the most substantial effect on not realizing textbook outcome. If 'sufficient lymph node dissection' was not included as a criterion, textbook outcome would be 60.7%. Case-mix adjusted textbook outcome proportions per hospitals varied between 13.2% and 37.7%.CONCLUSIONS: In contrast to focusing on a single aspect, the composite measure textbook outcome provides insight into comprehensive performance in NSCLC surgery. It can be used to evaluate both individual hospitals and national performance and provides the opportunity to give benchmarked feedback to thoracic surgeons.Thoracic Surger
Impact of health care organization on surgical lung cancer care
ObjectivesOrganization and governance of national healthcare might play an important role in decision-making and outcomes in patients with lung cancer. Both Denmark and the Netherlands have a high level of healthcare but a different financial coverage, governance and level of centralization. By using both national databases we analyzed the consequences of these differences on patterns of care and outcomes with a focus on morbidity, mortality and clinical staging.Materials and methodsGeneral numbers on both healthcare systems were requested. All patients who had surgery for lung cancer from 2013 to 2016 were included. Mortality, morbidity and clinical staging were analyzed for patients with NSCLC without metastases, only one operation and no neo-adjuvant therapy.ResultsIn 2016 annual budget as share of gross national product was 10.4% for both countries. In Denmark 4 hospitals performed lung surgery in 2016, compared to 43 hospitals in the Netherlands. We included 4030 Danish and 8286 Dutch patients. In the subgroup 30-day mortality was 1.5% in Denmark compared to 1.9% in the Netherlands. The percentage of patients with a complicated course was 24.4% and 34.8% respectively (p ConclusionSurgery for lung cancer is at a high level in both countries, reflected by low mortality-rates. Centralization has been implemented successfully in Denmark, which might explain the lower rate of patients with a complicated post-operative course, although different definitions preclude firm conclusions. In both countries correct clinical staging of lung cancer remains a challenge.</div
An update on the Hirsch conjecture
The Hirsch conjecture was posed in 1957 in a letter from Warren M. Hirsch to
George Dantzig. It states that the graph of a d-dimensional polytope with n
facets cannot have diameter greater than n - d.
Despite being one of the most fundamental, basic and old problems in polytope
theory, what we know is quite scarce. Most notably, no polynomial upper bound
is known for the diameters that are conjectured to be linear. In contrast, very
few polytopes are known where the bound is attained. This paper collects
known results and remarks both on the positive and on the negative side of the
conjecture. Some proofs are included, but only those that we hope are
accessible to a general mathematical audience without introducing too many
technicalities.Comment: 28 pages, 6 figures. Many proofs have been taken out from version 2
and put into the appendix arXiv:0912.423
Magnetic fields in cosmic particle acceleration sources
We review here some magnetic phenomena in astrophysical particle accelerators
associated with collisionless shocks in supernova remnants, radio galaxies and
clusters of galaxies. A specific feature is that the accelerated particles can
play an important role in magnetic field evolution in the objects. We discuss a
number of CR-driven, magnetic field amplification processes that are likely to
operate when diffusive shock acceleration (DSA) becomes efficient and
nonlinear. The turbulent magnetic fields produced by these processes determine
the maximum energies of accelerated particles and result in specific features
in the observed photon radiation of the sources. Equally important, magnetic
field amplification by the CR currents and pressure anisotropies may affect the
shocked gas temperatures and compression, both in the shock precursor and in
the downstream flow, if the shock is an efficient CR accelerator. Strong
fluctuations of the magnetic field on scales above the radiation formation
length in the shock vicinity result in intermittent structures observable in
synchrotron emission images. Resonant and non-resonant CR streaming
instabilities in the shock precursor can generate mesoscale magnetic fields
with scale-sizes comparable to supernova remnants and even superbubbles. This
opens the possibility that magnetic fields in the earliest galaxies were
produced by the first generation Population III supernova remnants and by
clustered supernovae in star forming regions.Comment: 30 pages, Space Science Review
Ionic and electronic structure of sodium clusters up to N=59
We determined the ionic and electronic structure of sodium clusters with even
electron numbers and 2 to 59 atoms in axially averaged and three-dimensional
density functional calculations. A local, phenomenological pseudopotential that
reproduces important bulk and atomic properties and facilitates structure
calculations has been developed. Photoabsorption spectra have been calculated
for , , and to
. The consistent inclusion of ionic structure considerably
improves agreement with experiment. An icosahedral growth pattern is observed
for to . This finding is supported by
photoabsorption data.Comment: To appear in Phys. Rev. B 62. Version with figures in better quality
can be requested from the author
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