Heterotopic Pregnancy, It is Such a Rare Finding?

Heterotopic pregnancy is a multiple pregnancy with simultaneous implantation of the embryos at two or more distinct locations. Risk factors, epidemiology, signs, symptoms, sonographic findings and management options are reviewed. Literature data indicates an increase of the prevalence of heterotopic pregnancy and a trend increase toward sonographic diagnosis at an earlier stage, before rupture. In order to facilitate early diagnosis, the dictum “think heterotopic” is never overemphasized also in the sonographic evi- dence for an intrauterine pregnancy. Diagnostic vigilance is particularly recommended in in-vitro fertilization with multiple embryo transfer even in the case of intrauterine twin visualization. Finally management options are examined

Cervicoscopy and Microcolposcopy in the Evaluation of Squamo Columnar Junction and Cervical Canal in LSIL Patients with Inadequate or Negative Colposcopy

OBJECTIVE: The present study evaluated indications’ validity of cervicoscopic and microcolposcopic examination in LSIL patients with unsatisfactory or negative colposcopy. MATHERIAL AND METHODS: In the cervico-vaginal pathology unit of the “San Giovanni Calibita Fatebenefratelli” University of Rome “Tor Vergata”, 119 patients with a positive cervical cytology (LSIL), were submitted to the exam for the following two indications: 1) unsatisfactory colposcopy 37 (31.1%); 2) negative colposcopy 82 (68.9%). RESULTS: Cervicoscopy allowed the SCJ visualization in 115 (9.6%) patients. In 4 patients 3.4%, the SCJ visualization was not possible due to cervical stenosis. Cervicoscopy without staining, revealed endocervical squamous columnar junction in 33 (28.7%) patients. The blue dye in panoramic view detected endocervical SCJ in 41 (35.7%), out of 115 patients (>5 mm in 34 (29.6%) patients and >10 mm in 7 (6.1%)). CONCLUSIONS: Cervicoscopic examination revealed 7.8% of CIN2-3 in LSIL patients with inadequate or negative colposcopy. In patients with negative colposcopy the percentage of undiagnosed lesions inside the cervical canal was very low. The blue dye added sensitivity to the exam

Optimization of thermochromic VO2-based structures with tunable thermal emissivity

In this paper we design and simulate VO2/metal multilayers to obtain a large tunability of the thermal emissivity of IR filters in the typical MWIR window of many infrared cameras. The multilayer structure is optimized to realise a low-emissivity filter at high temperatures useful for military purposes. The values of tunability found for VO2/metal multilayers are larger than the value for a single thick layer of VO2. Innovative SiO2/VO2 synthetic opals are also investigated to enhance the optical tunability by combining the properties of a 3D periodic structure and the specific optical properties of vanadium dioxide

Emissivity characterization of different stainless steel textiles in the infrared range

We experimentally investigated the infrared properties of a set of steel textiles, prepared using different type of fabrics. Infrared emission of the textiles was characterized in the mid-infrared range, i.e. 8÷14 mm, by observing their temperature evolution under heating regime with a focal plane array (FPA) infrared camera. Standard test method for measuring and compensating emissivity using infrared imaging radiometers was applied to the set of metallic textiles. The obtained experimental results allowed to retrieve the infrared emissivity at different applied temperatures. Although their infrared emission show some differences depending on the specific fabric, all the investigated textiles composed of steel yarns appear to be suitable for thermal shielding applications. Finally, the measured data were interpreted by means of the finite-difference time-domain (FDTD) numerical simulations as well as using Plank's theory of black-body radiation

Optothermal characterization of vanadium dioxide films by Infrared Thermography

The thickness of vanadium dioxide (VO2) films is a crucial parameter for the study of their optical and thermal properties. In this paper we studied the effect of the film thickness on the thermal hysteresis loop during the phase transition of VO2 deposited on a sapphire substrate by pulsed laser deposition (PLD), by the application of the Infrared Thermography technique. We measure the main thermal hysteresis parameters of VO2 samples with different thicknesses in the LWIR range (8–14 μm) showing how the transition temperature during the heating and cooling cycles, and the width of the hysteresis loop, may change with thickness. We analyzed and compared the obtained results with, in situ Grazing Incidence X-Ray Diffraction (GI-XRD). A good agreement between the results obtained with the two techniques was found demonstrating the reliability of the IR Thermography as a quantitative characterization tool. The results show that the structural and IR emissivity properties of the VO2 layer exhibit a dynamic range dependent on the layer thickness due to a correlation with the crystalline grain size. This has important effects in view of a tailored energy management for the use of those materials as smart radiators or smart windows

Asymmetric transmission and anomalous refraction in metal nanowires metasurface

Here we investigated the asymmetric transmission and the anomalous refraction introduced by a metasurface of bent gold nanowires. The refraction follows the generalized Snell's law that takes into account the resonant behavior of metallic nanostructures located at the interface between two dielectrics. Measurements performed in the linear optical regime reveal a large sensitivity to the subwavelength features of the gold nanostructures