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Organic–inorganic perovskites such as CH 3 NH 3 PbI 3 are promising materials for a variety of optoelectronic applications, with certified power conversion efficiencies in solar cells already exceeding 21%. Nevertheless, state-of-the-art films still contain performance-limiting non-radiative recombination sites and exhibit a range of complex dynamic phenomena under illumination that remain poorly understood. Here we use a unique combination of confocal photoluminescence (PL) microscopy and chemical imaging to correlate the local changes in photophysics with composition in CH 3 NH 3 PbI 3 films under illumination. We demonstrate that the photo-induced ‘brightening’ of the perovskite PL can be attributed to an order-of-magnitude reduction in trap state density. By imaging the same regions with time-of-flight secondary-ion-mass spectrometry, we correlate this photobrightening with a net migration of iodine. Our work provides visual evidence for photo-induced halide migration in triiodide perovskites and reveals the complex interplay between charge carrier populations, electronic traps and mobile halides that collectively impact optoelectronic performance. Visual evidence for photo-induced ionic migration in perovskite films without contacts is lacking. Here, the authors use a unique combination of confocal photoluminescence microscopy and chemical imaging to correlate the local changes in photophysics with composition in CH 3 NH 3 PbI 3 films under illumination.

The degradation of 3,4-dihydroxybenzoic acid (3,4-DHBA) in the presence and absence of Pb2+ under UV illumination was studied. Addition of Pb2+ caused the formation of precipitate during photoreaction when the solution pH was higher than 6. The presence of Pb2+ remarkably inhibited the degradation of 3,4-DHBA and its photodegradation intermediates, while complexation of 3,4-DHBA and its photodegradation intermediates with Pb2+ decreased the free Pb2+ in aqueous solutions. Molecular oxygen played an important role in photodegradation of 3,4-DHBA in the presence of Pb2+. UV–Vis spectroscopy was used to investigate the interaction between Pb2+ and 3,4-DHBA at different pH conditions, and FT-IR was used to characterize the precipitate formed during photoreaction. The mineralization of 3,4-DHBA was investigate by total organic carbon analysis.

Introduction The gold standard in general radiography is to place a radiopaque anatomical side marker in the field of view for each radiographic image prior to exposure. The advent of digital radiography has allowed for anatomical side markers to be digitally added to films as part of post‐processing. The aim of this audit was to identify whether general X‐ray images performed in a tertiary Women's and Children's Hospital were being appropriately annotated with a definitive side marker, and to identify factors that may contribute to inappropriately labelled images. Methods Four hundred images from 201 patients’ examinations occurring within a randomly selected time period were assessed to ascertain whether radiographic anatomical side markers were visible when images were viewed via the hospitals main viewing platform. The audit occurred in January 2014. The scope included both mobile and in‐department general X‐ray examinations, with the patient age range extending from 1 day to 18 years. Results Of the 400 images evaluated, 88 (22%) were found to have a lead marker that matched the anatomy being imaged within the primary beam; 289 (72.3%) images contained a correct digital marker inserted as part of the post‐processing of the image. In total, 377 (94.2%) images were appropriately marked. Of the 23 (5.8%) images not marked correctly, 22 images had no marker and 1 was incorrectly marked with a digital marker. There was a noticeable relationship between absent anatomical markers and chest X‐rays performed outside of the medical imaging department. Conclusions While it is encouraging that the majority of the images assessed were correctly annotated, with only a small number of missing markers, there are opportunities for further improvement. The audit findings suggest that reduced access to lead markers influences marker use. Strategies that may improve compliance at an individual level include distribution of personalised anatomical side markers, and targeted staff education sessions. At a department level, regular audits and monitoring should be encouraged. The aim of this audit was to identify whether all general X‐ray images were appropriately annotated with a definitive anatomical side marker, and to identify modifiable factors that contribute to inappropriately labelled images. Mislabelled radiographs represent an unjustifiable risk to patient safety. Of the 400 images evaluated, 23 (5.8%) images were not marked correctly.

Monte Carlo methods have been applied to the problem of gamma ray induced electron transport. The energy spectrum, the angular distribution and the efficiency of electrons emitted from aluminum and lead exposed to 1.25 MeV gamma rays were calculated and compared to experimental data obtained by using 60 Co source. Only Compton scattering and photoelectric interactions were considered and the effect of delta rays was ignored. Although the agreement between Monte Carlo and measured results was generally good, the considerable difference between them was showed for the emission efficiency in backward direction.

Heavy metal stress negatively affects the growth of medicinal plants. While the effects of Helium–Neon (He–Ne) laser on seed germination and stress tolerance in plants has garnered significant attention, little is known concerning the impacts of He–Ne laser irradiation on heavy metal tolerance in plants. Therefore, the current study was conducted to appraise the effect of different durations (0, 20, and 40 min) of seed priming with He–Ne laser (10 mW mm −2 ) on the antioxidant system of Silybum marianum L. plants under various Pb concentrations (0, 250, and 500 ppm). Lead phytotoxicity was evident by significant reductions in fresh and dry weights of shoots and roots, total chlorophyll (TChl) content and relative water content (RWC), as well as increases in H 2 O 2 and malondialdehyde contents in roots and leaves. Seed irradiation with He–Ne laser for 20 min significantly improved these parameters, enhancing Pb tolerance. Conversely, the prolonged laser priming (40 min) resulted in less favorable outcomes, including reduced growth, TChl content, and RWC, while also exacerbating oxidative damage to membranes even under non-stressful conditions. The 20-min laser priming systemically mitigated Pb-induced lipid peroxidation and H 2 O 2 accumulation by boosting the activities of superoxide dismutase and catalase and increasing proline content in leaves and roots of milk thistle plants. These findings and multivariate analysis suggest that optimal dose of laser initiates a “stress memory” in seeds which is activated upon subsequent exposure to Pb stress, boosting the plant defensive mechanisms and enabling the plant to better cope with oxidative damage. This study underscore the promising potential of He–Ne laser priming as a novel strategy for increasing heavy metal tolerance in medicinal plants like milk thistle, offering an eco-friendly technique for maintaining their productivity under heavy metal stress.

Endovascular operators experience elevated rates of occupational orthopedic injuries and persistent radiation exposure with current lead shielding. Novel shielding systems eliminate the need to wear lead aprons while also mitigating occupational radiation exposure, but real-world evidence of their efficacy remains needed. This study evaluated consecutive endovascular procedures requiring fluoroscopy at U.S. and international institutions following installation of a commercially available portable shielding system consisting of interlocking radiation-attenuating acrylic and soft shielding components. Live dosimeters were placed at the left shoulder of the main and assistant operators for quantification of radiation exposure. In total, 1,712 endovascular procedures performed by 671 operators at 153 sites (19% non-U.S.). In 1,712 (99.4%), radiation exposure was recorded. A majority of procedures (83.6%) were coronary interventions including diagnostic angiography (43.8%), nonchronic total occlusion PCI (27.6%), and chronic total occlusion PCI (6.7%). Median fluoroscopy time was 7.7 mins (IQR 3.9 to 15.3 min), and median radiation exposure to the main operator and first assistant was 2 μSv and 1 μSv. This was comparable to historical measurements of under-lead radiation exposure. In conclusion, the Rampart system effectively reduced radiation exposure in real-world practice, enabling a safe lead-free procedure lab.

An isolated black yeast-like strain was obtained from radiation-polluted soil collected from Xinjiang province in northwest China. On the basis of ITS and LSU rDNA sequence analysis, in combination with the colony morphology and phenotypic properties, the isolated strain was revealed to represent a novel variety of Aureobasidium subglaciale , designated as A. subglaciale F134. Compared to other yeasts and bacteria, this isolate displayed superior resistance to gamma irradiation, UV light, and heavy metal ions. It was discovered that the resistance of the isolate was correlated with the stress protector trehalose. Through the overexpression of the trehalose-6-phosphate synthase gene tps1 and the deletion of acid trehalase gene ath1 , the AP T∆A double mutant exhibited a survival rate of 1% under 20 kGy of gamma-radiation, 2% survival rate at a UV dosage of 250 J/m 2 , and tolerance towards Pb 2+ as high as 1500 mg/L, which was in agreement with the high accumulation of intracellular trehalose compared to the wild-type strain. Finally, the protective effects and the mechanism of trehalose accumulation in A. subglaciale F134 were investigated, revealing a significant activation of the expression of many of the stress tolerance genes, offering new perspectives on the adaptations of radioresistant microorganisms.

In recent decades, limited studies have explored the beneficial effects of seed irradiation with Helium-Neon (He-Ne) laser on secondary metabolism and stress tolerance in medicinal plants. However, the impact of laser on heavy metal tolerance and accumulation in these herbs is still largely unknown. To address this, a factorial experiment was conducted to examine the effects of various durations (0, 20, 40 min) of seed irradiation with He-Ne laser (10 mW m⁻²) on Pb tolerance and phytoremediation potential of milk thistle ( Silybum marianum L.) in soils spiked with varying Pb concentrations (0, 250, 500 ppm). Exposure to both concentrations of Pb decreased emergence, growth parameters, and chlorophyll (Chl.) contents, and seed irradiation with the laser significantly affected these attributes in a dose-dependent manner. The 20 min laser irradiation increased emergence percentage (29.48%, 54.48%), dry mass of roots (52.31%, 38.07%) and shoots (23.36%, 31.71%), height (18.60%, 17.06%), tolerance index (30.29%, 29.35%), Chl. a (25.76%, 21.37%) and Chl. b (52.32%, 60.33%) contents, total phenol content (43.55%, 27.40%), and DPPH scavenging activity (30%, 18.37%) in leaves of milk thistle at 250, and 500 ppm of Pb in soil. This treatment also reduced electrolyte leakage in roots (38.52%, 36.01%) and in leaves (19.22%, 30.05%) by enhancing the activity of peroxidase and ascorbate peroxidase enzymes, particularly at 500 ppm of Pb. Contrarily, 40 min irradiation had adverse effects on growth and tolerance index, increased EL levels, and lowered antioxidant enzyme activity at all Pb levels, highlighting the critical role of fine-tuned dose regulation. Interestingly, 20 min irradiation to the laser reduced Pb concentration in roots (13.26%) without altering its translocation to shoots while increasing the total Pb uptake (21.14%) under 500 ppm of Pb. These findings highlight the potential of seed laser irradiation as an innovative and eco-friendly technique to enhance the phytoremediation efficiency of milk thistle while preserving the quality and safety of plants cultivated in Pb-polluted soils for medicinal purposes.