166 research outputs found
Experimental demonstration of fractional orbital angular momentum entanglement of two photons
The singular nature of a non-integer spiral phase plate allows easy
manipulation of spatial degrees of freedom of photon states. Using two such
devices, we have observed very high dimensional (D > 3700) spatial entanglement
of twin photons generated by spontaneous parametric down-conversion.Comment: submitted to Phys. Rev. Let
Detection of sub-shot-noise spatial correlation in high-gain parametric down-conversion
Using a 1GW-1ps pump laser pulse in high gain parametric down-conversion
allows us to detect sub-shot-noise spatial quantum correlation with up to one
hundred photoelectrons per mode, by means of a high efficiency CCD. The
statistics is performed in single-shot over independent spatial replica of the
system. The paper highlights the evidence of quantum correlation between
symmetrical signal and idler spatial areas in the far field, in the high gain
regime. In accordance with the predictions of numerical calculations the
observed transition from the quantum to the classical regime is interpreted as
a consequence of the narrowing of the down-converted beams in the very high
gain regime.Comment: 4,2 pages, 4 figure
Shannon dimensionality of quantum channels and its application to photon entanglement
We introduce the concept of Shannon dimensionality D as a new way to quantify
bipartite entanglement as measured in an experiment. This is applied to
orbital-angular-momentum entanglement of two photons, using two state analyzers
composed of a rotatable angular-sector phase plate that is lens-coupled to a
single-mode fiber. We can deduce the value of D directly from the observed
two-photon coincidence fringe. In our experiment, D varies between 2 and 6,
depending on the experimental conditions. We predict how the Shannon
dimensionality evolves when the number of angular sectors imprinted in the
phase plate is increased and anticipate that D = 50 is experimentally within
reach.Comment: 4 pages, 3 figures, accepted for Physical Review Letter
Non-locality of high-dimensional two-photon orbital angular momentum states
Quantum Matter and Optic
Optical vortices with starlight: Implications for ground-based stellar coronagraphy
Using an l = 1 blazed fork-hologram at the focal plane of the Asiago 122 cm
telescope, we obtained optical vortices from the stellar system Rasalgethi
(alpha Herculis) and from the single star Arcturus (alpha Bootis). We have
analyzed the structure of the optical vortices obtained from non-monochromatic
starlight under very poor seeing conditions using a fast CCD camera to obtain
speckle patterns and carry out the lucky imaging technique, alternative to
adaptive optics. With the insertion of a red filter and of a Lyot stop we
performed l = 1 optical vortex coronography the double star HD74010. The
results are in agreement with theory and numerical simulations. Our results
open the way to applications of optical vortices to ground based astronomical
observations, in particular for coronagraphy with l > 1 masks. No intrinsic
orbital angular momentum was detected in the starlight.Comment: 4 pages, 5 figures. Revised data analysi
How to observe high-dimensional two-photon entanglement with only two detectors
Quantum Matter and Optic
Effect of spatial filtering on the Schmidt decomposition of entangled photons
Quantum Matter and Optic
Clinical Outcomes of Percutaneous Coronary Intervention for Bifurcation Lesions According to Medina Classification
Background: Coronary bifurcation lesions (CBLs) are frequently encountered in clinical practice and are associated with worse outcomes after percutaneous coronary intervention. However, there are limited data around the prognostic impact of different CBL distributions. /
Methods and Results: All CBL percutaneous coronary intervention procedures from the prospective e‐Ultimaster (Prospective, Single‐Arm, Multi Centre Observations Ultimaster Des Registry) multicenter international registry were analyzed according to CBL distribution as defined by the Medina classification. Cox proportional hazards models were used to compare the hazard ratio (HR) of the primary outcome, 1‐year target lesion failure (composite of cardiac death, target vessel–related myocardial infarction, and clinically driven target lesion revascularization), and its individual components between Medina subtypes using Medina 1.0.0 as the reference category. A total of 4003 CBL procedures were included. The most prevalent Medina subtypes were 1.1.1 (35.5%) and 1.1.0 (26.8%), whereas the least prevalent was 0.0.1 (3.5%). Overall, there were no significant differences in patient and procedural characteristics among Medina subtypes. Only Medina 1.1.1 and 0.0.1 subtypes were associated with increased target lesion failure (HR, 2.6 [95% CI, 1.3–5.5] and HR, 4.0 [95% CI, 1.6–9.0], respectively) at 1 year, compared with Medina 1.0.0, prompted by clinically driven target lesion revascularization (HR, 3.1 [95% CI, 1.1–8.6] and HR, 4.6 [95% CI, 1.3–16.0], respectively) as well as cardiac death in Medina 0.0.1 (HR, 4.7 [95% CI, 1.0–21.6]). No differences in secondary outcomes were observed between Medina subtypes. /
Conclusions: In a large multicenter registry analysis of coronary bifurcation percutaneous coronary intervention procedures, we demonstrate prognostic differences in 1‐year outcomes between different CBL distributions, with Medina 1.1.1 and 0.0.1 subtypes associated with an increased risk of target lesion failure
Patient-Reported Morbidity Instruments: A Systematic Review
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Objectives: Although comorbidities play an essential role in risk adjustment and outcomes measurement, there is little consensus regarding the best source of this data. The aim of this study was to identify general patient-reported morbidity instruments and their measurement properties. Methods: A systematic review was conducted using multiple electronic databases (Embase, Medline, Cochrane Central, and Web of Science) from inception to March 2018. Articles focusing primarily on the development or subsequent validation of a patient-reported morbidity instrument were included. After including relevant articles, the measurement properties of each morbidity instrument were extracted by 2 investigators for narrative synthesis. Results: A total of 1005 articles were screened, of which 34 eligible articles were ultimately included. The most widely assessed instruments were the Self-Reported Charlson Comorbidity Index (n = 7), the Self-Administered Comorbidity Questionnaire (n = 3), and the Disease Burden Morbidity Assessment (n = 3). The most commonly included conditions were diabetes, hypertension, and myocardial infarction. Studies demonstrated substantial variability in item-level reliability versus the gold standard medical record review (κ range 0.66-0.86), meaning that the accuracy of the self-reported comorbidity data is dependent on the selected morbidity. Conclusions: The Self-Reported Charlson Comorbidity Index and the Self-Administered Comorbidity Questionnaire were the most frequently cited instruments. Significant variability was observed in reliability per comorbid condition of patient-reported morbidity questionnaires. Further research is needed to determine whether patient-reported morbidity data should be used to bolster medical records data or serve as a stand-alone entity when risk adjusting observational outcomes data.Federation of Dutch University Medical Centers (NFU)Gliklich Healthcare Innovation Scholar Fund/Massachusetts Eye and Ear InfirmaryAmerican Board of Medical Specialtie
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