Universal lateral distribution of energy deposit in air showers and its application to shower reconstruction

The light intensity distribution in a shower image and its implications to the primary energy reconstructed by the fluorescence technique are studied. Based on detailed CORSIKA energy deposit simulations, a universal analytical formula is derived for the lateral distribution of light in the shower image and a correction factor is obtained to account for the fraction of shower light falling into outlying pixels in the detector. The expected light profiles and the corresponding correction of the primary shower energy are illustrated for several typical event geometries. This correction of the shower energy can exceed 10%, depending on shower geometry.Comment: 21 pages, 9 figure

Nanometric deformations of thin Nb layers under a strong electric field using soft x-ray laser interferometry

International audienceWe present measurements of in situ nanometric-resolution topographical modifications of thin niobium layers subjected to strong electric fields. The Nb layers, deposited on a fused silica substrate, are interferometrically flash probed using soft x-ray laser (XRL) at the wavelength of 21.2 nm. Its pulses are reflected by the probed sample under grazing incidence angle, and the information about surface deformation is obtained by a Fresnel wave-front-division interferometer. It was experimentally established that the probing pulses at the soft x-ray wavelength do neither produce any measurable photoelectric-field emission, nor alter the topographical features of the probed surface. The examined Nb electrodes were periodically probed while the electric field was increased up to 80 MV/m, and alterations of their topographical characteristics with a resolution of ∼2 nm in the relief elevation were obtained. It was found that behavior of the Nb layer strongly depends on the polarity of the applied voltage. Only small modifications are observed with the Nb surface at the positive potential, whereas the negative potential induces significant transient surface perturbations, with peak-to-valley elevation differences ∼50 nm. The qualitative nature of these modifications was observed to be unrelated to intermittent parasitic breakdowns

Electrochemotherapy for Breast Cancer

Skin metastases occur more commonly in breast cancer (BC) than in any other malignancy in women, exceeding 20\u2009% of all cutaneous metastases. They most commonly present on the chest wall (CW), but the abdomen, back, scalp, and upper extremities also are sites of occurrence. Presentation may be ambiguous; nevertheless, their local progression may lead to extensive CW infiltration or fungating masses, with associated symptoms (e.g., bleeding, oozing, smell) and severe patient discomfort. Since cutaneous metastases portends an incurable diagnosis, the use of locoregional treatment focuses on preventing uncontrolled tumor spread, palliating symptoms, and preserving QoL. The first clinical experiences with electrochemotherapy in BC date back to the 1990s and indicated an objective response rate up to 90\u2009%, with 59\u2009% of subjects achieving local complete remission. More recently, following the standardization of the procedure, thanks to the adoption of the European Standard Operating Procedures of Electrochemotherapy (ESOPE) in 2006, sustained complete response rates (range, 26\u201358\u2009%) have been confirmed, with durable CW control. Due to its mainly dermatologic toxicity profile, the treatment can be safely repeated, the principal concerns being pain control and lung toxicity, particularly when maximum cumulative exposure to bleomycin is reached. Early patient referral and advanced wound management are crucial aspects for ensuring patient comfort after electrochemotherapy. The most recently published experience, based on the retrospective analysis of 125 patients, indicates a 58\u2009% complete response rate, with 86\u2009% 1-year local progression-free survival. In this study, small tumor size, hormone receptor positivity, low proliferative index, and absence of visceral metastases were predictors of response. Electrochemotherapy represents an efficacious treatment modality for cutaneous metastases and holds promise in the management of patients with metastatic as well as locoregional (skin-only recurrence) BC. Future well-designed clinical trials will clarify the role of electrochemotherapy in BC and explore its rational combination with systemic agents