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Here, we highlight the potential translational benefits of delivering FLASH radiotherapy using ultra-high dose rates (>100 Gy⋅s-1). Compared with conventional dose-rate (CONV; 0.07-0.1 Gy⋅s-1) modalities, we showed that FLASH did not cause radiation-induced deficits in learning and memory in mice. Moreover, 6 months after exposure, CONV caused permanent alterations in neurocognitive end points, whereas FLASH did not induce behaviors characteristic of anxiety and depression and did not impair extinction memory. Mechanistic investigations showed that increasing the oxygen tension in the brain through carbogen breathing reversed the neuroprotective effects of FLASH, while radiochemical studies confirmed that FLASH produced lower levels of the toxic reactive oxygen species hydrogen peroxide. In addition, FLASH did not induce neuroinflammation, a process described as oxidative stress-dependent, and was also associated with a marked preservation of neuronal morphology and dendritic spine density. The remarkable normal tissue sparing afforded by FLASH may someday provide heretofore unrealized opportunities for dose escalation to the tumor bed, capabilities that promise to hasten the translation of this groundbreaking irradiation modality into clinical practice.

210Po is a radioactive component of conventional cigarette tobacco smoke and is a recognized carcinogen. Despite the expanding market of heated tobacco products, no data are available on the activity of 210Po in the smoke of IQOS Heets cigarette. We determined the 210Po activity in the mainstream smoke of thirteen cigarette brands available on the Swiss market using a smoking machine and compared the results to the 210Po activity measured in the mainstream smoke of the IQOS system. In addition, we measured the 210Po and 210Pb loss on heating after uniform heating from 50 to 600 °C for several cigarette brands and the Heets cigarettes. 13.6 ± 4.1% of 210Po activity was found in the mainstream smoke in conventional cigarette smoking (7% for 210Pb). This dropped to 1.8 ± 0.3% in the mainstream smoke of IQOS Heets. Conversely, when the tobacco was heated uniformly at 330 °C, a loss of 210Po of more than 80% was observed for all type of cigarettes. Apparently, IQOS significantly reduced the 210Po and 210Pb activities in the mainstream smoke. However, our results show that only 15% of the Heets tobacco reaches 330 °C with IQOS. While IQOS reduces the 210Po and 210Pb activities in the mainstream smoke compared to conventional cigarettes, it only heats a marginal fraction of the tobacco present in the Heets cigarette. Because smoking is an addiction (mostly due to nicotine), IQOS could possibly deliver an unsatisfactory dose of nicotine to a Heets cigarette smoker, as most of the tobacco is left unaltered. [ABSTRACT FROM AUTHOR]

Researchers from Switzerland investigated effects of preferential flow path in the the spatial distribution of radionuclides in soil and its corresponding transfer to plant roots.

In 90Sr analysis, determining its daughter 90Y improves the sensitivity of the radiometric methods. We found that to imprint a cavity made of [Y(6-(4-Vinylphenylcarbamoyl)pyridine-2-carboxylate)3] into a polystyrene skeleton yields a solid phase extraction resin with high selectivity for Y and Ln(III) over transition metals, alkaline, and alkaline-earth cations. We used this resin in an automated chromatography system to extract 90Y from milk, grass, vegetables, soil, sediments, water, human bones, and milk teeth samples. We found that the ion-imprinted resin could be used to separate light Ln(III) using a pH gradient, favoring the targeting of molecules used in nuclear medicine. [ABSTRACT FROM AUTHOR]

The new solids of the general formula (MLx)(Ln{dipic}3)n.H2O (M = Cr or Co; L = urea, ammonia and various amines; Ln =La-Lu, plus Y; dipic = pyridine- 2,6-dicarboxylate) are synthesized. In the orthorhombic Cs3(Eu{dipic}3).9H2O and monoclinic (Co{sar})(Eu{dipic}3).13H2O the two cations are bridged by the dipicolinate carboxylate groups. Cr(III) and Co(III) are characterized as quenchers of the normally strong (Eu/Tb{dipic}3)3- luminescence. Excitation energy is transferred from the higher levels of Cr(III) to Ln excited states.

Homo- and hetero-dinuclear neutral complexes of composition ((Ln1:Ln2)LH2(DMF)5)(DMF)n, where n is 4 (alpha-phase) or 1.5 (beta-phase), are formed when the macrocyclic octaphenol p-tert-butylcalix(8)arene (LH8) reacts with lanthanide (III) ions in dimethyl formamide (DMF) that has triethylamine. A perfect selectivity of the ligand for ions midway between the lanthanide series is present in the Ln (III) content, as revealed by the ICP-AES determination. The two lanthanide (III) ions incorporated by the ligands are similar in pseudo C3h symmetry, as indicated by the luminescence measurements at 77 kelvin.

The reactions of various derivatives of chelidamic acid (4-hydroxypyridine-2,6-dicarboxylic acid) with p-tert-butylcalix[4]arene have produced both mono- and di-lower rim - substituted calixarenes with the capacity to bind rare earth metal (lanthanide) cations. The two difunctionalized calixarene ligands and the Eu(III) complex of the deprotonated form of a monofunctionalized ligand are characterized by X-ray crystallography.