276 research outputs found
Quantum Estimation Methods for Quantum Illumination
Quantum illumination consists in shining quantum light on a target region
immersed in a bright thermal bath, with the aim of detecting the presence of a
possible low-reflective object. If the signal is entangled with the receiver,
then a suitable choice of the measurement offers a gain with respect to the
optimal classical protocol employing coherent states. Here, we tackle this
detection problem by using quantum estimation techniques to measure the
reflectivity parameter of the object, showing an enhancement in the
signal-to-noise ratio up to 3 dB with respect to the classical case when
implementing only local measurements. Our approach employs the quantum Fisher
information to provide an upper bound for the error probability, supplies the
concrete estimator saturating the bound, and extends the quantum illumination
protocol to non-Gaussian states. As an example, we show how Schrodinger's cat
states may be used for quantum illumination.Comment: Published versio
Aceite de silicona para el tratamiento de la maculopatía hipotónica
Case report: We report a case of a man who developed hypotonic maculopathy after vitreoretinal surgery for anterior proliferative vitreoretinopathy. After an injection of intravitreal triamcinolone, the ocular pressure did not increase, therefore silicone oil was injected. After this, the visual acuity increased and the choroidal and retinal folds regressed.
Discussion: Hypotonic maculopathy is a frustrating problem, often resulting in poor visual acuity. There are not many effective treatments. The injection of silicone oil could be an alternative to increase the intraocular pressure and re-establish the normal anatomy of the eye, improving the visual acuity in some patient
Hemorragia submacular traumática tratada con rt-PA y SF6
This patient was afflicted by a traumatic submacular hemorrhage. A
posterior vitrectomy was performed and intravitreal rt-PA and SF6 were
administered. Four weeks later, the visual acuity had increased from 0.1 to 0.8.
No complications due to the treatment with rt-PA were reported. DISCUSSION: It is
known that waiting for the spontaneous blood removal in such cases results in a
poor visual acuity recovery due to a toxic effect of the blood products. Both
rt-PA and the SF6 are useful for the treatment of submacular hemorrhages
secondary to age-related macular degeneration, and this case report has shown
they are also useful to lyse traumatic blood clots, thus contributing to a better
recovery of visual acuity
Oftalmopatía tiroidea: determinación de parámetros de actividad clínica de la oftalmopatía tiroidea como factor pronóstico de respuesta al tratamiento inmunosupresor
Objective: To determine the usefulness of the clinical, biochemical and thyroid imaging parameters in patients with thyroid-associated ophthalmopathy, in predicting their response to immunosuppressive treatment.
Methods: This retrospective study of 16 patients with thyroid ophthalmopathy considered a number of variables including sex, age, thyroid hormone levels, treatment of the thyroid dysfunction, clinical activity score (CAS), severity (NOSPECS) of the ophthalmopathy, signs in standardized A-mode ultrasonography, in CAT and/or NMR, and previously used treatments and their effectiveness.
Results: The average age of the patients was 50.81 (S.D: 11.89) years; there were 5 males (31.3%) and 11 females (68.8%). The ophthalmopathy was classified as active in 10/16 patients (62.5%) and inactive in 6/16 (37.5%); and as moderate in 9/16 (56.25%) and severe in 7/16 (43.75%) according to the severity defined in NOSPECS. Ultrasonography was diagnostic in 100% of the cases.
The severity decreased significantly (p ≤ 0.05), however the clinical activity decrease did not reach significance (p=0.38) during immunosuppressive therapy. Better results were obtained during treatment of patients with a higher CAS (p=0.04) and in those with more severe ophthalmopathy (p=0.02). There was a tendency for the patients with higher levels of TSI to respond better to the treatment (p=0.06).
Conclusions: The CAS is the best parameter to quantify the activity of the disease and predicting the response to treatment. The higher the CAS and the more severe the ophthalmopathy, the better the response to treatment. No association existed between thyroid function and the activity or severity of the ophthalmopathy; or the effectiveness of treatmen
Improving the activity in hydrodechlorination of Pd/C catalysts by nitrogen doping of activated carbon supports
Aqueous phase 4-chlorophenol hydrodechlorination reaction was used to study the effect of N-doping of activated carbon support on the catalytic activity of Pd catalysts. Activated carbon was doped using pyridine and 1,10-phenantroline, reaching nitrogen contents of 0.42-1.22 and 1.35-4.19 % (w), respectively. All catalysts (0.75 % Pd w, carbon basis) showed relatively large Pd nanoparticles (35-55nm), but they exhibited fast and complete 4-chlorophenol disappearance in batch experiments. In runs at 30°C 4-chlorophenol disappearance was mainly ascribed to hydrodechlorination, although N-doping of the support also increased adsorption. Catalysts with supports doped with pyridine yielded higher 4-chlorophenol disappearance rate in spite of lower bulk nitrogen content, however they showed higher concentration of nitrogen species at the external surface and lower loss of surface area during the doping. 4-chlorophenol disappearance rate was boosted at 60°C, with minor differences between catalysts with undoped and N-doped supports, but generation of cyclohexanone was only observed for the ones with doped support. Phenol generation simultaneous to 4-chlorophenol disappearance was observed with all the catalysts. However, subsequent hydrogenation to cyclohexanone ocurred only with the catalysts supported on N-doped activated carbonThe authors greatly appreciate the financial support of this research from the Spanish Ministry of Economy and Competitiveness through the project CTQ2012-3282
Development and implementation of a web-enabled 3D consultation tool for breast augmentation surgery based on 3D-image reconstruction of 2D pictures
Producing a rich, personalized Web-based consultation tool for plastic surgeons and patients is challenging
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