Calcifying Aponeurotic Fibroma: A Multimodal Imaging Description of an Unusual Case Involving Soft Tissues Adjacent to the Clavicle.

Calcifying aponeurotic fibromas (CAFs) are rare benign tumors that typically develop in the soft tissue of the extremities. We report a case of 64-year-old woman with a CAF in the soft tissue surrounding her left clavicle. A plain radiograph showed an asymmetrical increase in opacity of the left internal clavicular region. Computed tomography and magnetic resonance imaging confirmed the presence of a heterogeneous lesion of the periclavicular soft tissue, with peripheral calcifications, and remodeling of the adjacent clavicular bone. Following ultrasound-guided biopsy and surgical resection of the mass, the final histological diagnosis was made. To the best of our knowledge, this is the first case of a CAF described in the soft tissue adjacent to the clavicle. It is essential to use all the diagnostic methods available (X-ray, ultrasound, CT, MRI, and percutaneous biopsy) to obtain the final diagnosis of this rare disease.

Directional Ultrasound Source for Solid Materials Inspection: Diffraction Management in a Metallic Phononic Crystal.

In this work, we numerically investigate the diffraction management of longitudinal elastic waves propagating in a two-dimensional metallic phononic crystal. We demonstrate that this structure acts as an "ultrasonic lens", providing self-collimation or focusing effect at a certain distance from the crystal output. We implement this directional propagation in the design of a coupling device capable to control the directivity or focusing of ultrasonic waves propagation inside a target object. These effects are robust over a broad frequency band and are preserved in the propagation through a coupling gel between the "ultrasonic lens" and the solid target. These results may find interesting industrial and medical applications, where the localization of the ultrasonic waves may be required at certain positions embedded in the object under study. An application example for non-destructive testing with improved results, after using the ultrasonic lens, is discussed as a proof of concept for the novelty and applicability of our numerical simulation study.

Defect reconstruction by non-destructive testing with laser induced ultrasonic detection.

This work envisages a detailed study of two-dimensional defect localization and reconstruction, using laser generated ultrasound and its application as a remotely controlled non-destructive testing method. As an alternative to full ultrasonic or full optical approaches, we propose a hybrid configuration where ultrasound is generated by impact of laser pulses, while the detection is done with conventional transducers. We implement this approach for defect reconstruction in metallic elements and show that it combines advantages of both photonic and ultrasonic devices, reducing the drawbacks of both methods. We combine our experimental results with a high-resolution signal processing procedure based on the synthetic aperture focusing technique for the benefit of the final two-dimensional visualization of the defects.

Fully Noncontact Hybrid NDT for 3D Defect Reconstruction Using SAFT Algorithm and 2D Apodization Window.

Nondestructive testing of metallic objects that may contain embedded defects of different sizes is an important application in many industrial branches for quality control. Most of these techniques allow defect detection and its approximate localization, but few methods give enough information for its 3D reconstruction. Here we present a hybrid laser-transducer system that combines remote, laser-generated ultrasound excitation and noncontact ultrasonic transducer detection. This fully noncontact method allows access to scan areas on different object's faces and defect details from different angles/perspectives. This hybrid system can analyze the object's volume data and allows a 3D reconstruction image of the embedded defects. As a novelty for signal processing improvement, we use a 2D apodization window filtering technique, applied along with the synthetic aperture focusing algorithm, to remove the undesired effects due to side lobes and wide-angle reflections of propagating ultrasound waves, thus enhancing the resulting 3D image of the defect. Finally, we provide both qualitative and quantitative volumetric results that yield valuable information about defect location and size.

Laser Ultrasound Inspection Based on Wavelet Transform and Data Clustering for Defect Estimation in Metallic Samples.

Laser-generated ultrasound is a modern non-destructive testing technique. It has been investigated over recent years as an alternative to classical ultrasonic methods, mainly in industrial maintenance and quality control procedures. In this study, the detection and reconstruction of internal defects in a metallic sample is performed by means of a time-frequency analysis of ultrasonic waves generated by a laser-induced thermal mechanism. In the proposed methodology, we used wavelet transform due to its multi-resolution time frequency characteristics. In order to isolate and estimate the corresponding time of flight of eventual ultrasonic echoes related to internal defects, a density-based spatial clustering was applied to the resulting time frequency maps. Using the laser scan beam's position, the ultrasonic transducer's location and the echoes' arrival times were determined, the estimation of the defect's position was carried out afterwards. Finally, clustering algorithms were applied to the resulting geometric solutions from the set of the laser scan points which was proposed to obtain a two-dimensional projection of the defect outline over the scan plane. The study demonstrates that the proposed method of wavelet transform ultrasonic imaging can be effectively applied to detect and size internal defects without any reference information, which represents a valuable outcome for various applications in the industry.

Controllable coherent backscattering of light in disordered media filled with liquid crystal.

We have investigated multiple scattering of light in a disordered system based on liquid crystals for a temperature-controllable random laser. Coherent backscattering measurements at several temperatures have been well fitted by the theoretical model deduced for a random collection of spherical point scatters based on a diffusion approximation. The transport mean free path exclusively depends on the diffusivity of the liquid crystalline phase of the hybrid scattering system. It is shown how the laser threshold excitation intensity is strongly correlated with the transport mean free path.

Influence of liquid crystalline phases on the tunability of a random laser.

In this paper, we report the temperature behavior of an optimized disordered photonic system-based liquid crystal by means of heat capacity and refractive index measurements. The scattering system is formed by a porous borosilicate glass random matrix (about 60%) infiltrated with a smectogenic liquid crystal (about 16%) and a small amount of laser dye (0.1%). The rest of the scattering system is about 24% air, giving rise to a high refractive index contrast scattering system. Such a system has the functionality to change the refractive index contrast with temperature due to the liquid crystal temperature behavior. The system, optically pumped by the second harmonic of a Q-switched Nd:YAG pulsed laser working at 532 nm, exhibits random laser action, the threshold of which depends upon the liquid crystalline mesophase. Temperatures of existence of the smectic-B phase correspond to the most optimized random laser. In such a mesophase, the transport mean free path has been determined as about 16 µm in a coherent backscattering experiment.

Quality of life in patients with non-muscle-invasive bladder cancer: one-year results of a multicentre prospective cohort study.

OBJECTIVE: Few studies describe the effect of non-muscle-invasive bladder cancer (NMIBC) on health-related quality of life (HRQL), although patients are mostly diagnosed at this stage of the disease. Taking into account this current evidence gap and the high incidence rates in Spain, we aimed to describe the evolution over time of HRQL in Spanish patients with NMIBC and to examine the clinical and treatment-related factors associated with HRQL change during the first year of management. METHODS AND MATERIALS: Observational multicenter prospective inception cohort study conducted in urology departments of 7 Spanish hospitals. A consecutive sample of 244 patients with anatomopathologically confirmed NMIBC, recruited from October 2010 to September 2011, was followed during the diagnostic process, and 6 and 12 months later. HRQL was assessed by generic and disease-specific instruments: the Short Form-36 (covering physical and mental health) and the Bladder Cancer Index, measuring urinary, bowel, and sexual domains (summary scores: 0-100). Bivariate analysis was performed and generalized estimating equation models were constructed to assess HRQL score change. RESULTS: Almost 52% of the patients were diagnosed at stage I, and 84% were men. The number of patients treated only with transurethral resection (TUR) was 144, and 82 also received intravesical therapy with bacillus Calmette-Guérin (BCG) or mitomycin C. Mental health was significantly worse than Short Form-36 reference norms at diagnosis (mean of 49.7 vs. 53.3, 95% CI: 52.5-54.2). Urinary domain improved significantly from diagnosis (85.2, 95% CI: 82.9-87.4) to 12-month evaluation (90.2, 95% CI: 87.7-92.8), whereas sexual domain showed deterioration from 56.4 (95% CI: 52.8-59.9) to 53.7 (95% CI: 50.0-57.4). Adjusted HRQL score changes from baseline to 12-month follow-up estimated with generalized estimating equation models showed improvement on the following parameters: urinary domain after TUR with or without intravesical therapy (+3.9, 95% CI: 0.1-7.7), bowel domain among patients treated with TUR and BCG (+7.0, 95% CI: 2.4-11.5), and sexual domain among those treated with TUR and mitomycin C (+13.1, 95% CI: 5.9-20.2). CONCLUSIONS: For the first time, a distinctive HRQL pattern of bladder cancer treatment benefits emerges for TUR alone, and in combination with BCG or mitomycin C, which deserves further research. Treatment differences cannot be interpreted in terms of efficacy but can be useful to generate hypotheses to test in future studies.

Unified approach to Cerenkov second harmonic generation.

We discuss the effect of second harmonic generation via the Cerenkov-like process in nonlinear bulk media and waveguides. We show that in both schemes the Cerenkov harmonic emission represents in fact a nonlinear Bragg diffraction process. It is therefore possible, for the first time, to describe the bulk and waveguide Cerenkov emission uniformly by considering the spatial modulation of the second-order nonlinear polarization. This is also experimentally illustrated by studying the Cerenkov second harmonic generation at the boundary of a nonlinear quadratic medium via the total internal reflection inside the nonlinear crystal.

Type I and type II second harmonic generation of conically refracted beams.

Type I and type II second harmonic generation (SHG) of a beam transformed by the conical refraction phenomenon are presented. We show that, for type I, the second harmonic intensity pattern is a light ring with a point of null intensity while, for type II, the light ring possesses two dark regions. Taking into account the different two-photon processes involved in SHG, we have derived analytical expressions for the resulting transverse intensity patterns that are in good agreement with the experimental data. Finally, we have investigated the spatial evolution of the second harmonic signals, showing that they behave as conically refracted beams.

Multi-directional Cerenkov second harmonic generation in two-dimensional nonlinear photonic crystal.

We study Cerenkov-type second-harmonic generation in a two-dimensional quasi-periodically poled LiNbO3 crystal. We employ a new geometry of interaction to observe simultaneous emission of multi-directional nonlinear Cerenkov radiation with comparable intensities. This opens a way to control the angle of Cerenkov emission by tailoring the nonlinearity of the material, which is otherwise intrinsically defined by dielectric constants of the medium and their dispersion.

Tailoring Cerenkov second-harmonic generation in bulk nonlinear photonic crystal.

We investigate theoretically the Cerenkov-type second-harmonic generation in two-dimensional bulk nonlinear photonic crystal with longitudinal modulation of the χ((2)) nonlinearity. We show that in this scheme the Cerenkov radiation can be achieved simultaneously at multiple directions with comparable intensities. The angles of emission are controllable by the spatial modulation of the nonlinearity. We propose a design of the periodically poled domain pattern, which maximizes the efficiency of the second-harmonic emission.

Planar second-harmonic generation with noncollinear pumps in disordered media.

We study experimentally the process of the second harmonic generation by two noncollinear beams in quadratic nonlinear crystals with a disordered structure of ferroelectric domains. We show that the second-harmonic radiation is emitted in the form of two cones as well as in a plane representing the cross-correlation of the two fundamental pulses. We demonstrate the implementation of this parametric process for characterisation of femtosecond pulses, enabling the estimation of pulse width, chirp, and front tilt. This is achieved through monitoring the evolution of the autocorrelation trace inside the nonlinear crystal.

Second-harmonic parametric scattering in ferroelectric crystals with disordered nonlinear domain structures.

We study the second-harmonic (SH) parametric processes in unpoled crystals of Strontium Barium Niobate (SBN) with disordered structures of ferroelectric domains. Such crystals allow for the simultaneous phase matching of several second-order nonlinear processes. We analyze the polarization properties of these parametric processes using two types of generation schemes: quasi-collinear SH generation and transverse SH generation. From our experimental data we determine the ratio of d(32) and d(33) components of the second order susceptibility tensor and also the statistical properties of the random structure of the SBN crystal.

Determination of refractive indices of quarter-wavelength Bragg reflectors by reflectance measurements in wavelength and angular domains.

We show that all the structural properties of periodic dielectric multilayers can be accurately determined by a combined measurement of the transmission as a function of the wavelength and of the reflection as a function of the angle of incidence when the wavelength of the incident light is fixed. This method is applied to determine the structural properties of two commercial dielectric mirrors, and the results obtained are compared with a measurement of the same structural parameters by use of another technique based on the more standard optical guiding method.

Colored conical emission by means of second-harmonic generation.

We predict that the combination of space and time modulational instabilities that occur by means of parametric wave mixing in quadratic media leads to colored conical emission. This phenomenon should be observed under conditions usually employed in second-harmonic experiments.