1,469 research outputs found
Signal-to-noise properties of correlation plenoptic imaging with chaotic light
Correlation Plenoptic Imaging (CPI) is a novel imaging technique, that
exploits the correlations between the intensity fluctuations of light to
perform the typical tasks of plenoptic imaging (namely, refocusing out-of-focus
parts of the scene, extending the depth of field, and performing 3D
reconstruction), without entailing a loss of spatial resolution. Here, we
consider two different CPI schemes based on chaotic light, both employing ghost
imaging: the first one to image the object, the second one to image the
focusing element. We characterize their noise properties in terms of the
signal-to-noise ratio (SNR) and compare their performances. We find that the
SNR can be significantly higher and easier to control in the second CPI scheme,
involving standard imaging of the object; under adequate conditions, this
scheme enables reducing by one order of magnitude the number of frames for
achieving the same SNR.Comment: 12 pages, 3 figure
Tricriticalities and Quantum Phases in Spin-Orbit-Coupled Spin- Bose Gases
We study the zero-temperature phase diagram of a spin-orbit-coupled
Bose-Einstein condensate of spin , with equally weighted Rashba and
Dresselhaus couplings. Depending on the antiferromagnetic or ferromagnetic
nature of the interactions, we find three kinds of striped phases with
qualitatively different behaviors in the modulations of the density profiles.
Phase transitions to the zero-momentum and the plane-wave phases can be induced
in experiments by independently varying the Raman coupling strength and the
quadratic Zeeman field. The properties of these transitions are investigated in
detail, and the emergence of tricritical points, which are the direct
consequence of the spin-dependent interactions, is explicitly discussed.Comment: 6 pages, 2 figures + Supplemental Material. Revised version,
published in PR
Quantum crossover in moderately damped epitaxial NbN/MgO/NbN junctions with low critical current density
High quality epitaxial NbN/MgO/NbN Josephson junctions have been realized
with MgO barriers up to a thickness of d=1 nm. The junction properties
coherently scale with the size of barrier, and low critical current densities
down to 3 A/cm have been achieved for larger barriers. In this limit,
junctions exhibit macroscopic quantum phenomena for temperatures lower than 90
mK. Measurements and junction parameters support the notion of a possible use
of these devices for multiphoton quantum experiments, taking advantage of the
fast non equilibrium electron-phonon relaxation times of NbN
Ascariasis in a 75-year-old man with small bowel volvulus: a case report
Background: Ascaris lumbricoides and Ascaris suum are the most common soil-transmitted helminths of humans and pigs, respectively. The zoonotic potential of A. suum has been a matter of debate for decades. This study was aimed to present a case of human ascariasis caused by A. suum in southern Italy. Case presentation: A 75-year-old man presented to the department of surgery in Avellino (southern Italy) complaining of abdominal pain and vomiting. Physical examination revealed bloating and abdominal tenderness. A computed tomography scan showed air-fluid levels and small bowel distension. During exploratory laparotomy a small bowel volvulus with mesenteritis was evident and surprisingly an intraluminal worm was detected. The worm was removed with a small enterotomy and identified as an adult female of A. suum based on morphological and molecular analysis. Faecal examination revealed the presence of unfertilized Ascaris eggs with an intensity of 16 eggs per gram (EPG) of faeces. The patient was treated with mebendanzole 100 mg twice a day for 3 days. The post-operative course was regular with re-alimentation after 3 days and discharge after 12 days. Conclusions: This report shows as A. suum can function as a relevant agent of human zoonosis. Therefore, in patients with bowel obstruction with no evident aetiology a helminthic infestation should be considered for an accurate diagnosis, especially in patients living in rural areas.Fil: Romano, Giovanni. Frieri-Criscuoli Hospital; ItaliaFil: Pepe, Paola. Università degli Studi di Napoli Federico II; ItaliaFil: Cavallero, Serena. Università di Roma; ItaliaFil: Cociancic, Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Di Libero, Lorenzo. Frieri-Criscuoli Hospital; ItaliaFil: Grande, Giovanni. Frieri-Criscuoli Hospital; ItaliaFil: Cringoli, Giuseppe. Università degli Studi di Napoli Federico II; ItaliaFil: D'Amelio, Stefano. Università di Roma; ItaliaFil: Rinaldi, Laura. Università degli Studi di Napoli Federico II; Itali
Omalizumab in Chronic Spontaneous Urticaria Refractory to Conventional Therapy: An Italian Retrospective Clinical Analysis with Suggestions for Long-Term Maintenance Strategies
Introduction: Omalizumab is indicated for the treatment of patients affected by chronic spontaneous urticaria (CSU) refractory to antihistamines. The aim of this study was to assess the efficacy, safety, and recurrence of symptoms in a real-life experience of omalizumab as an add-on therapy for H1-antihistamine-refractory CSU patients (refractory CSU). Methods: A retrospective review of the clinical records of all refractory CSU treated with omalizumab at our dermatology center from June 2014 to April 2017 was performed. Patients previously treated with second-generation antihistamines at a fourfold increased dose without clinical responses at 4 weeks of treatment were selected. Omalizumab was administered at a single dosage of 300 mg every 4 weeks for 6 months. Disease severity was assessed using the 7-day Urticaria Activity Score (UAS7). Results: Eighteen patients (14 women; mean age 51 years, range 25-74) were enrolled. Mean UAS7 at baseline was 27.3 (range 15-38). Symptoms improved in all patients at 4 weeks (UAS7 = 16.1, range 0-36). Treatment was completed in 17 patients (94.4%), and among these, a complete response (UAS7 = 0) was registered in 10 patients (58.8%). Adverse events included thrombocytopenia in 1 patient (5.6%) at 16 weeks; therapy was suspended after 20 weeks and the complication was resolved, resulting in a freedom from major adverse events of 94.4%. Symptom recurrence occurred in 3 patients (17.6%) at 4, 5, and 7 months from the end of the primary therapy. Retreatment with omalizumab was successful without any adverse effects. Mean follow-up was 9.5 months (range 1-28). Conclusion: Add-on omalizumab therapy for refractory CSU in a real-life setting seems to be effective and safe with a relatively low incidence of symptom recurrence. Further research should investigate personalized omalizumab treatment dosages and administration intervals, and the identification of biomarkers for future treatment algorithms
Distance sensing emerging from second-order interference of thermal light
We introduce and describe a technique for distance sensing, based on
second-order interferometry of thermal light. The method is based on measuring
correlation between intensity fluctuations on two detectors, and provides
estimates of the distances separating a remote mask from the source and the
detector, even when such information cannot be retrieved by first-order
intensity measurements. We show how the sensitivity to such distances is
intimately connected to the degree of correlation of the measured interference
pattern in different experimental scenarios and independently of the spectral
properties of light. Remarkably, this protocol can be also used to measure the
distance of remote reflective objects in the presence of turbulence. We
demonstrate the emergence of new critical parameters which benchmark the degree
of second-order correlation, describing the counterintuitive emergence of
spatial second-order interference not only in the absence of (first-order)
coherence at both detectors but also when first order interference is observed
at one of the two detectors.Comment: 6 pages, 3 figure
Pigmented Nodular Basal Cell Carcinomas in Differential Diagnosis with Nodular Melanomas: Confocal Microscopy as a Reliable Tool for In Vivo Histologic Diagnosis
Nodular basal cell carcinoma, especially when pigmented, can be in differential diagnosis with nodular melanomas, clinically and dermoscopically. Reflectance confocal microscopy is a relatively new imaging technique that permits to evaluate in vivo skin tumors with a nearly histological resolution. Here, we present four cases of challenging nodular lesions where confocal microscopy was able to clarify the diagnosis
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