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Background: The rise in asthma has been linked to different environmental and lifestyle factors including dietary habits. Whether dietary salt contributes to asthma incidence, remains controversial. We aimed to investigate the impact of higher salt intake on asthma incidence in humans and to evaluate underlying mechanisms using mouse models. Methods: Epidemiological research was conducted using the UK Biobank Resource. Data were obtained from 42,976 participants with a history of allergies. 24‐h sodium excretion was estimated from spot urine, and its association with asthma incidence was assessed by Cox regression, adjusting for relevant covariates. For mechanistic studies, a mouse model of mite‐induced allergic airway inflammation (AAI) fed with high‐salt diet (HSD) or normal‐salt chow was used to characterize disease development. The microbiome of lung and feces (as proxy for gut) was analyzed via 16S rRNA gene based metabarcoding approach. Results: In humans, urinary sodium excretion was directly associated with asthma incidence among females but not among males. HSD‐fed female mice displayed an aggravated AAI characterized by increased levels of total IgE, a TH2‐TH17‐biased inflammatory cell infiltration accompanied by upregulation of osmosensitive stress genes. HSD induced distinct changes in serum short chain fatty acids and in both gut and lung microbiome, with a lower Bacteroidetes to Firmicutes ratio and decreased Lactobacillus relative abundance in the gut, and enriched members of Gammaproteobacteria in the lung. Conclusions: High dietary salt consumption correlates with asthma incidence in female adults with a history of allergies. Female mice revealed HSD‐induced T‐cell lung profiles accompanied by alterations of gut and lung microbiome. [ABSTRACT FROM AUTHOR]

We give an overview of the special challenges regarding target development and production for accelerator-based heavy and superheavy-nuclei experiments in the past and perspectives for the future. Production of ever heavier elements, studies of heavy-element production in fusion or transfer reactions, spectroscopic investigations on their nuclear structure and decay and on the fission processes with fragment analyses, laser spectroscopic studies of their atomic structure, high-precision mass measurements as well as chemical studies are lively fields of current science. The ever-increasing beam intensities, feasible with new accelerator development, are crucial for the synthesis of superheavy elements because of the low cross sections for many of the reactions. Therefore, the development of target and backing materials with higher durability and experiment lifetime is increasingly important. Here we concentrate on the techniques necessary for the production of targets that are needed for experiments in this special field of interest. For the future, also development on target monitoring, target cooling, and beam intensity profile shaping techniques will play an important role, but are not in the focus of this article. [ABSTRACT FROM AUTHOR]

Ions of the isomer 229mTh are a topic of high interest for the construction of a "nuclear clock" and in the field of fundamental physics for testing symmetries of nature. They can be efficiently captured in Paul traps which are ideal for performing high precision quantum logic spectroscopy. Trapping and identification of long-lived 232Th+ ions from a laser ablation source was already demonstrated by the TACTICa collaboration on Trapping And Cooling of Thorium Ions with Calcium. The 229mTh is most easily accessible as α-decay daughter of the decay of 233U. We report on the development of a source for slow Th ions, including 229mTh for the TACTICa experiment. The 229mTh source is currently under construction and comprises a 233U monolayer, from which 229mTh ions recoil. These are decelerated in an electric field. Conservation of the full initial charge state distribution of the 229mTh recoil ions is one of the unique features of this source. We present ion-flight simulations for our adopted layout and give a final source design. This source will provide Th ions in their original charge state at energies suitable for capture in a linear Paul trap for spectroscopy investigations. [ABSTRACT FROM AUTHOR]

Thorium ions exhibit unique nuclear properties with high relevance for testing symmetries of nature, and Paul traps feature an ideal experimental platform for performing high precision quantum logic spectroscopy. Loading of stable or long-lived isotopes is well-established and relies on ionization from an atomic beam. A different approach allows trapping short-lived isotopes available as alpha-decay daughters, which recoil from a thin sample of the precursor nuclide. A prominent example is the short-lived 229mTh, populated in a decay of long-lived 233U. Here, ions are provided by an external source and are decelerated to be available for trapping. Such setups offer the option to trap various isotopes and charge states of thorium. Investigating this complex procedure, we demonstrate the observation of single 232Th+ ions trapped, embedded into and sympathetically cooled via Coulomb interactions by co-trapped 40Ca+ ions. Furthermore, we discuss different options for a non-destructive identification of the sympathetically cooled thorium ions in the trap, and describe in detail our chosen experimental method, identifying mass and charge of thorium ions from the positions of calcium ions, as their fluorescence is imaged on a CCD camera. These findings are verified by means of a time-of-flight signal when extracting ions of different mass-to-charge ratio from the Paul trap and steering them into a detector. [ABSTRACT FROM AUTHOR]

229Th is the only nucleus currently under investigation for the development of a nuclear optical clock (NOC) of ultra-high accuracy. The insufficient knowledge of the first nuclear excitation energy of 229Th has so far hindered direct nuclear laser spectroscopy of thorium ions and thus the development of a NOC. Here, a nuclear laser excitation scheme is detailed, which makes use of thorium atoms instead of ions. This concept, besides potentially leading to the first nuclear laser spectroscopy, would determine the isomeric energy to 40 μeV resolution, corresponding to 10 GHz, which is a 104 times improvement compared to the current best energy constraint. This would determine the nuclear isomeric energy to a sufficient accuracy to allow for nuclear laser spectroscopy of individual thorium ions in a Paul trap and thus the development of a single-ion nuclear optical clock. [ABSTRACT FROM AUTHOR]