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Fast emitting polymeric scintillators are requested in advanced applications where high speed detectors with a large signal-to-noise ratio are needed. However, their low density implies a weak stopping power of high energy radiation and thus a limited light output and sensitivity. To enhance their performance, polymeric scintillators can be loaded with dense nanoparticles (NPs). We investigate the properties of a series of polymeric scintillators by means of photoluminescence and scintillation spectroscopy, comparing standard scintillators with a composite system loaded with dense hafnium dioxide (HfO 2 ) NPs. The nanocomposite shows a scintillation yield enhancement of +100% with an unchanged time response. We provide for the first time an interpretation of this effect, pointing out the local effect of NPs in the generation of emissive states upon interaction with ionizing radiation. The obtained results indicate that coupling fast conjugated emitters with optically inert dense NPs could lead to surpassing the actual limits of pure polymeric scintillators.

Composite polymer electrolytes are systems of choice for future solid-state lithium metal batteries (LMBs). Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) is among the most interesting matrices to develop new generation quasi-solid electrolytes (QSEs). Here it is reported on nanocomposites made of PVDF-HFP and pegylated SiO 2 nanoparticles. Silica-based hybrid nanofillers are obtained by grafting chains of poly(ethylene glycol) methyl ether (PEG) with different molecular weight on the surface of silica nanoparticles. The functionalized nanofiller improves the mechanical, transport and electrochemical properties of the QSEs, which show good ionic conductivity values and high resistance against dendrite penetration, ensuring boosted long and safe device operation. The most promising result is obtained by dispersing 5 wt% of SiO 2 functionalized with short PEG chains (PEG 750 , Mw = 750 g mol -1 ) in the PVDF-HFP matrix with an ease solvent-casting procedure. It shows ionic conductivity of 0.1 mS cm -1 at 25 °C, more than 250 h resistance to stripping/plating, and impressive results during cycling tests in LMB with LiFePO 4 cathode., (© 2024 Wiley‐VCH GmbH.)

Transparent nanocomposite films made of surface-modified titanium dioxide nanoparticles and thermoplastic polyurethane are prepared via film casting approach showing enhanced refractive indexes and mechanical properties. Two different sets of composites were prepared up to 37.5 wt % of inorganic nanoparticles with a diameter <15 nm, one set using particles capped only with oleic acid and a second one with a bimodal system layer made of oleic acid and mPEO-5000 as coating agents. All of the composites show significantly enhanced refractive index and mechanical properties than the neat polymeric matrix. The transparency of nanocomposite films shows the excellent dispersion of the inorganic nanoparticles in the polymeric matrix avoiding aggregation and precipitation phenomena. Our study provides a facile and feasible route to produce transparent nanocomposite films with tunable mechanical properties and high refractive indices for various applications., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Background: Nipple-sparing mastectomy is commonly performed for breast cancer treatment or prevention. The authors present one of the largest breast reconstruction series in the literature., Methods: A single-institution retrospective review was conducted from 2007 to 2019., Results: The authors' query identified 3035 implant-based breast reconstructions after nipple-sparing mastectomy, including 2043 direct-to-implant and 992 tissue expander-to-implant reconstructions. The overall major complication rate was 9.15%, and the nipple necrosis rate was 1.20%. Therapeutic mastectomy was associated with higher overall complications and explantations compared with prophylactic mastectomy ( P < 0.01). In comparisons of unilateral and bilateral procedures, bilateral mastectomy had an increased risk for complications (OR, 1.46; 95% CI, 0.997 to 2.145; P = 0.05). Tissue-expander reconstructions had higher rates of nipple necrosis (1.9% versus 0.88%; P = 0.015), infection (4.2% versus 2.8%; P = 0.04), and explantation (5.1% versus 3.5%; P = 0.04) compared with direct-to-implant reconstruction. When assessing plane of reconstruction, the authors found similar rates of complications between subpectoral dual-plane and prepectoral reconstruction. There was no difference in complications between reconstruction with acellular dermal matrix or mesh compared with total or partial muscle coverage without acellular dermal matrix/mesh (OR, 0.749; 95% CI, 0.404 to 1.391; P = 0.361). Multivariable regression analysis revealed preoperative radiotherapy (OR, 2.465; 95% CI, 1.579 to 3.848; P < 0.001), smoking (OR, 2.53; 95% CI, 1.581 to 4.054; P < 0.001), and a periareolar incision (OR, 3.657; 95% CI, 2.276 to 5.875; P < 0.001) to be the strongest predictors of complications and nipple necrosis ( P < 0.05)., Conclusions: Nipple-sparing mastectomy and immediate breast reconstruction has a low rate of complications. In this series, radiation therapy, smoking, and incision choice predicted overall complications and nipple necrosis, whereas direct-to-implant reconstruction and acellular dermal matrix or mesh did not increase risk., Clinical Question/level of Evidence: Therapeutic, III., (Copyright © 2023 by the American Society of Plastic Surgeons.)