Nipple Reconstruction Using the “Arrow Flap” Technique: Outcomes and Patients Satisfaction

Introduction: Skin-sparing mastectomy (SSM) entails complete removal of the breast tissue and the nipple and areola complex (NAC) with preservation of as much of the overlying skin as possible. The preservation of the natural skin envelope during SSM improves the aesthetic outcome of immediate breast reconstruction, but the lack of NAC determines that the reconstructed breast remains anatomically incomplete with not always satisfactory final results. For this purpose, the aim of the present study was to investigate and evaluate the impact of nipple reconstruction after skin sparing and skin reducing mastectomy on the patients' perception and intimate life. Materials and method: This was a comparative single-center prospective study that involved 42 patients underwent NAC reconstruction after SSM. A pre- and postoperative quality-of-life and psychological questionnaires Breast-Q questionnaire (Breast Conserving therapy module) were given to all the patients before the surgery and 6 months after. The statistical analysis with chi-square test was performed. Results: After 6 months a prevalence of patients reported to be very satisfied in regard to shape, appearance, naturalness, projection, position and symmetry. The study shows an overall improvement in all the psychological items analyzed with statistically significant difference regarding: "patient's satisfaction," "self-confidence," "appearance of the breast." Conclusion: The authors believe that the NAC reconstruction has useful functional and aesthetic results particularly appreciated by patients who feel demoralized after breast demolition surgery

Characterization of Chirality in Diffractive Metasurfaces by Photothermal Deflection Technique

Chirality, a lack of mirror symmetry, is present in nature at all scales; at the nanoscale, it governs the biochemical reactions of many molecules, influencing their pharmacology and toxicity. Chiral substances interact with left and right circularly polarized light differently, but this difference is very minor in natural materials. Specially engineered, nanostructured, periodic materials can enhance the chiro-optical effects if the symmetry in their interactions with circular polarization is broken. In the diffraction range of such metasurfaces, the intensity of diffracted orders depends on the chirality of the input beam. In this work, we combine a photothermal deflection experiment with a novel theoretical framework to reconstruct both the thermal and optical behavior of chiro-optical behavior in diffracted beams

Asymmetric hole array: tuning the optical circular dichroism for chiral molecules sensing

Optical enantioselectivity of chiral molecules could be enhanced by depositing them on suitable nanostructured substrates. Different kind of chiral substrates can be developed, but chiral features are in general difficult to fabricate or costly. Self-assembled approach allows realizing plasmonic metasurfaces with a low cost reliable procedure. In this case asymmetric fabrication parameters can induce chiral optical response of the realised substrate. Self-organized polystyrene spheres deposited on glass substrate, are utilised to produce asymmetric hole array on a metal thin film. In our case the spheres (518 nm in diameter) where reduced by selective reactive ion etching and then covered by gold (and other metals), that is evaporated at a glancing angle. After the removing of the spheres an elliptical-hole array is produced forming a circular-dichroic substrate. The circular dichroic response of light interacting with the substrate can be tuned by choosing proper incidence angle and excitation wavelength, while the flat nature of the metasurface is very useful for easy molecular deposition processes. Two new enantiomers (right-handed and left-handed molecules) have been synthesized in order to present a good circular dichroism in the visible range and to be tested on the realized metasurfaces. Different tests were carried out on the samples, investigating the spectral optical properties of the structures with and without chiral molecules on top of them. The results are very promising due to the possibility of easily tuning and optimizing the optical response

Active Modulation of Er3+ Emission Lifetime by VO2 Phase‐Change Thin Films

The active modulation of optical response of quantum emitters at the nanoscale is of paramount importance to realize tunable light sources for nanophotonic devices. Herein, a thin film of phase-change material (VO2) is coupled to a 20 nm-thick silica layer embedding Er3+ ions, and it is demonstrated how the active tuning of the local density of optical states near the erbium emitters provided by the thermally induced semiconductor-to-metal transition of VO2 can be used to dynamically control the Er3+ emission lifetime at telecom wavelength (1.54 μm). A decay rate contrast of a factor 2 is obtained between high temperature (90 °C), when VO2 is metallic, and room temperature, when VO2 is semiconductor, in agreement with calculations performed with the classical dipole oscillator analytical model. A hysteretic behavior is observed by measuring the Er3+ lifetime as a function of the temperature, whose parameters are consistent with those of grazing incidence X-ray diffraction and optical transmittance measurements. The fractions of Er3+ ions that couple with VO2 in each phase at the different temperatures are determined by the analysis of the temporal decays. The results make the investigated system an optimal candidate for the development of tunable photon sources at telecom wavelength

Characterization of output circular polarization degree in lowcost asymmetric metasurfaces

Addition of asymmetry in plasmonic nanostructures can lead to chiro-optical phenomena, usually monitored as different absorption of left and right polarization, i.e. circular dichroism. Moreover, interesting features arise when the nanostructure changes the polarization state of the input beam. In this work, we perform extrinsic chirality characterization in a widely tuneable near-infrared range, by monitoring both polarization of the input and of the transmitted beam. We characterize low-cost metasurfaces based on polystyrene nanospheres asymmetrically covered by Ag, by exciting them at different angle of incidence with left, right and linear polarization. We then resolve the circular polarization degree of the transmitted beam, demonstrating resonance-governed circular polarization degree in the output, showing the interplay of both intrinsic and extrinsic chirality

Experiments and simulations of chiro-optical response in lowcost nanohole arrays in silver

2D metasurfaces based on periodic nanoholes in metal have been proposed in various plasmonic platforms. Specifically, their resonant features have led to applications spanning in biosensing. Here we investigate additional degree of freedom in elliptical nanohole arrays with hexagonal geometry: chiro-optical effects. Namely, the in-plane asymmetry and a slightly elliptical shape of nanoholes were previously shown to differently extinct light of opposite handedness, even at normal incidence. We now fully characterize nanoholes in Ag, fabricated by low-cost nanosphere lithography. We first measure the dependence of the transmitted intensity for opposite handedness, in a broad spectral and angle of incidence range. We then resolve the circular polarization degree of the transmitted light when the nanohole array is excited with linear polarization. Finally, we numerically investigate the origin of the chiro-optical effect at the nanoscale. We believe that circular polarization resolving of the transmitted degree could be further adapted as a highly sensitive tool in chiral sensing

Silver Nanoprism Arrays Coupled to Functional Hybrid Films for Localized Surface Plasmon Resonance-Based Detection of Aromatic Hydrocarbons

We report the achievement of sensitive gas detection using periodic silver nanoprisms fabricated by a simple and low-cost lithographic technique. The presence of sharp tips combined with the periodic arrangement of the nanoprisms allowed the excitement of isolated and interacting localized surface plasmon resonances. Specific sensing capabilities with respect to aromatic hydrocarbons were achieved when the metal nanoprism arrays were coupled in the near field with functional hybrid films, providing a real-time, label-free, and reversible methodology. Ultra-high-vacuum temperature-programmed desorption measurements demonstrated an interaction energy between the sensitive film and analytes in the range of 55-71 kJ/mol. The far-field optical properties and the detection sensitivity of the sensors, modeled using a finite element method, were correlated to experimental data from gas sensing tests. An absorbance variation of 1.2% could be observed and associated with a theoretical increase in the functional film refractive index of similar to 0.001, as a consequence to the interaction with 30 ppm xylene. The possibility of detecting such a small variation in the refractive index suggests the highly promising sensing capabilities of the presented technique

ENUBET: A monitored neutrino beam for high precision cross section measurements

International audienceThe main source of systematic uncertainty on neutrino cross section measurements at the GeV scale is represented by the poor knowledge of the initial flux. The goal of cutting down this uncertainty to 1% can be achieved through the monitoring of charged leptons produced in association with neutrinos, by properly instrumenting the decay region of a conventional narrow-band neutrino beam. Large angle muons and positrons from kaons are measured by a sampling calorimeter on the decay tunnel walls (tagger), while muon stations after the hadron dump can be used to monitor the neutrino component from pion decays. This instrumentation can provide a full control on both the muon and electron neutrino fluxes at all energies. Furthermore, the narrow momentum width (<10%) of the beam provides a O(10%) measurement of the neutrino energy on an event by event basis, thanks to its correlation with the radial position of the interaction at the neutrino detector. The ENUBET project has been funded by the ERC in 2016 to prove the feasibility of such a monitored neutrino beam and is cast in the framework of the CERN neutrino platform (NP06) and the Physics Beyond Colliders initiative. In our contribution, we summarize the ENUBET design, physics performance and opportunities for its implementation in a timescale comparable with next long baseline neutrino experiments