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The Chernobyl accident was probably the worst possible catastrophe of a nuclear power station. It was the only such catastrophe since the advent of nuclear power 55 years ago. It resulted in a total meltdown of the reactor core, a vast emission of radionuclides, and early deaths of only 31 persons. Its enormous political, economic, social and psychological impact was mainly due to deeply rooted fear of radiation induced by the linear non-threshold hypothesis (LNT) assumption. It was a historic event that provided invaluable lessons for nuclear industry and risk philosophy. One of them is demonstration that counted per electricity units produced, early Chernobyl fatalities amounted to 0.86 death/GWe-year), and they were 47 times lower than from hydroelectric stations (∼40 deaths/GWe-year). The accident demonstrated that using the LNT assumption as a basis for protection measures and radiation dose limitations was counterproductive, and lead to sufferings and pauperization of millions of inhabitants of contaminated areas. The projections of thousands of late cancer deaths based on LNT, are in conflict with observations that in comparison with general population of Russia, a 15% to 30% deficit of solid cancer mortality was found among the Russian emergency workers, and a 5% deficit solid cancer incidence among the population of most contaminated areas.

The Sykes commentary advocates "a more sensible, graded approach for protection from low dose ionizing radiation" until the LNT dose-response issue is resolved. It urges scientists to stop criticizing the LNT model that links radiation to a risk of cancer and accept regulatory use of the threshold model to "protect" people, but with higher limits. It fails to mention the 120-year history of successful low-dose treatments of a wide variety of serious diseases, including cancers. The commentary ignores published evidence of a threshold at 1.1 Gy for radiogenic leukemia and a dose-rate threshold at about 0.6 Gy per year for lifespan shortening. LNT came from politicized science, replete with scientific misconduct and conflict of interest. Its acceptance created a false cancer scare that was likely intended to stop atomic bomb testing, but it has severely damaged human welfare. Many vitally important low-dose therapies were discarded when the radiation scare was disseminated in 1956. The rapid growth of nuclear energy ended with the media-inflamed public panic after the Three Mile Island accident in 1979. Extreme implementation of the precautionary principle made it uneconomic. Availability of a low-dose therapy for lung inflammation could have dramatically decreased the impact of the COVID-19 pandemic.

In this paper, the tolerance and stability versus SO2 of Ba0.9A0.1Ti0.8Cu0.2O3 (A = Sr, Ca, Mg) perovskite-type catalysts for NOx storage application have been analyzed at 400 °C. Characterization results show that only strontium and magnesium are introduced into the perovskite structure. From those data, it can be concluded that the incorporation of Sr into the Ba0.9Sr0.1Ti0.8Cu0.2O3 catalyst promotes the generation of new NOx adsorption active sites. On the contrary, for Ba0.9Mg0.1Ti0.8Cu0.2O3 catalyst, copper is segregated from the catalyst lattice to the surface due to the incorporation of magnesium into the B site of the perovskite. The partial substitution of barium in Ba0.9Sr0.1Ti0.8Cu0.2O3 and Ba0.9Mg0.1Ti0.8Cu0.2O3 catalysts increases the NOx Storage Capacity (460 and 415 μmol/g.cat. in saturation conditions, respectively), stability and tolerance versus SO2 compared to the raw BaTi0.8Cu0.2O3 perovskite. ; The authors thank Spanish Government (MINECO) and UE (FEDER Founding) (project CTQ2015-64801-R) and Generalitat Valenciana (project PROMETEO II/2018/076) for the financial support. V. Albaladejo-Fuentes thanks the University of Alicante for his Ph.D. grant.

ABSTRACTThe aim of this study was to test the inter‐rater reliability of a revised oral assessment guide (ROAG) for patients residing in a geriatric rehabilitation ward. A consecutive sample of 140 patients was recruited for the study. Oral assessments were performed for 133 newly admitted patients by one registered nurse (RN) during a period of six months. A dental hygienist (DH) carried out 103 oral assessments during the same half‐year. For 66 patients, the RN and the DH performed independent assessments. There was an agreement between the RN and the DH in the majority of the independent assessments, except for tongue and teeth/dentures. The percentage agreement exceeded 80 percent. Inter‐rater agreement measured by Cohen's Kappa coefficient ranged from moderate to very good and percentage agreement had a range of 58 to 91 percent. The agreement was highest in assessment of voice and swallowing (91%). Assessments of teeth and dentures seemed to be most difficult for the RN to evaluate. ROAG was found to be a clinically useful assessment tool. Additional education and training is needed to improve the reliability of the oral assessments and should include continuous support from a dental hygienist as well as a pictorial manual on how to use the ROAG.

The effect of partial Ti substitution by Mn, Fe, Co, or Cu on the NOx storage capacity (NSC) of a BaTi0.8B0.2O3 lean NOx trap (LNT) catalyst has been analyzed. The BaTi0.8B0.2O3 catalysts were prepared using the Pechini's sol–gel method for aqueous media. The characterization of the catalysts (BET, ICP-OES, XRD and XPS) reveals that: i) the partial substitution of Ti by Mn, Co, or Fe changes the perovskite structure from tetragonal to cubic, whilst Cu distorts the raw tetragonal structure and promotes the segregation of Ba2TiO4 (which is an active phase for NOx storage) as a minority phase and ii) the amount of oxygen vacancies increases after partial Ti substitution, with the BaTi0.8Cu0.2O3 catalyst featuring the largest amount. The BaTi0.8Cu0.2O3 catalyst shows the highest NSC at 400 °C, based on NOx storage cyclic tests, which is within the range of highly active noble metal-based catalysts. ; This research was funded by Generalitat Valenciana (PROMETEO/2018/076 and Ph.D. grant ACIF 2017/221), Spanish Government (MINECO Project CTQ2015-64801-R) and EU (FEDER Founding).