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Abstract A fast and reliable range monitoring method is required to take full advantage of the high linear energy transfer provided by therapeutic ion beams like carbon and oxygen while minimizing damage to healthy tissue due to range uncertainties. Quasi-real-time range monitoring using in-beam positron emission tomography (PET) with therapeutic beams of positron-emitters of carbon and oxygen is a promising approach. The number of implanted ions and the time required for an unambiguous range verification are decisive factors for choosing a candidate isotope. An experimental study was performed at the FRS fragment-separator of GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany, to investigate the evolution of positron annihilation activity profiles during the implantation of $$^{14}$$ 14 O and $$^{15}$$ 15 O ion beams in a PMMA phantom. The positron activity profile was imaged by a dual-panel version of a Siemens Biograph mCT PET scanner. Results from a similar experiment using ion beams of carbon positron-emitters $$^{11}$$ 11 C and $$^{10}$$ 10 C performed at the same experimental setup were used for comparison. Owing to their shorter half-lives, the number of implanted ions required for a precise positron annihilation activity peak determination is lower for $$^{10}$$ 10 C compared to $$^{11}$$ 11 C and likewise for $$^{14}$$ 14 O compared to $$^{15}$$ 15 O, but their lower production cross-sections make it difficult to produce them at therapeutically relevant intensities. With a similar production cross-section and a 10 times shorter half-life than $$^{11}$$ 11 C, $$^{15}$$ 15 O provides a faster conclusive positron annihilation activity peak position determination for a lower number of implanted ions compared to $$^{11}$$ 11 C. A figure of merit formulation was developed for the quantitative comparison of therapy-relevant positron-emitting beams in the context of quasi-real-time beam monitoring. In conclusion, this study demonstrates that among the positron emitters of carbon and oxygen, $$^{15}$$ 15 O is the most feasible candidate for quasi-real-time range monitoring by in-beam PET that can be produced at therapeutically relevant intensities. Additionally, this study demonstrated that the in-flight production and separation method can produce beams of therapeutic quality, in terms of purity, energy, and energy spread.

211Po ions in the ground and isomeric states were produced via 238U projectile fragmentation at 1000 MeV/u. The 211Po ions were spatially separated in flight from the primary beam and other reaction products by the fragment separator FRS. The ions were energy-bunched, slowed-down and thermalized in a gas-filled cryogenic stopping cell (CSC). They were then extracted from the CSC and injected into a high-resolution multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS). The excitation energy of the isomer and, for the first time, the isomeric-to-ground state ratio were determined from the measured mass spectrum. In the subsequent experimental step, the isomers were spatially separated from the ions in the ground state by an ion deflector and finally collected with a silicon detector for decay spectroscopy. This pioneering experimental result opens up unique perspectives for isomer-resolved studies. With this versatile experimental method new isomers with half-lives longer than a few milliseconds can be discovered and their decay properties can be measured with highest sensitivity and selectivity. These experiments can be extended to studies with isomeric beams in nuclear reactions. Keywords: Isotope separation in flight, Spatial isomer separation, Multiple-reflection time-of-flight mass spectrometer, Isomer, Isomeric beam, Excitation energy, Isomeric ratio, 211Po ions

Abstract A first-of-a-kind geological repository for spent nuclear fuel is being built in Finland and will soon start operations. To make sure all nuclear material stays in peaceful use, the fuel is measured with two complementary non-destructive methods to verify the integrity and the fissile content of the fuel prior to disposal. For pin-wise identification of active fuel material, a Passive Gamma Emission Tomography (PGET) device is used. Gamma radiation emitted by the fuel is assayed from 360 angles around the assembly with highly collimated CdZnTe detectors, and a 2D cross-sectional image is reconstructed from the data. At the encapsulation plant in Finland, there will be the possibility to measure in air. Since the performance of the method has only been studied in water, measurements with mock-up fuel were conducted at the Atominstitut in Vienna, Austria. Four different arrangements of activated Co-60 rods, steel rods and empty positions were investigated both in air and in water to confirm the functionality of the method. The measurement medium was not observed to affect the ability of the method to distinguish modified rod positions from filled rod positions. More extended conclusions about the method performance with real spent nuclear fuel cannot be drawn from the mock-up studies, since the gamma energies, activities, material attenuations and assembly dimensions are different, but full-scale measurements with spent nuclear fuel are planned for 2023.

RNA structural elements occur in numerous single-stranded positive-sense RNA viruses. The stem-loop 2 motif (s2m) is one such element with an unusually high degree of sequence conservation, being found in the 3' untranslated region (UTR) in the genomes of many astroviruses, some picornaviruses and noroviruses, and a variety of coronaviruses, including severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2. The evolutionary conservation and its occurrence in all viral subgenomic transcripts imply a key role for s2m in the viral infection cycle. Our findings indicate that the element, while stably folded, can nonetheless be invaded and remodeled spontaneously by antisense oligonucleotides (ASOs) that initiate pairing in exposed loops and trigger efficient sequence-specific RNA cleavage in reporter assays. ASOs also act to inhibit replication in an astrovirus replicon model system in a sequence-specific, dose-dependent manner and inhibit SARS-CoV-2 replication in cell culture. Our results thus permit us to suggest that the s2m element is readily targeted by ASOs, which show promise as antiviral agents. IMPORTANCE The highly conserved stem-loop 2 motif (s2m) is found in the genomes of many RNA viruses, including SARS-CoV-2. Our findings indicate that the s2m element can be targeted by antisense oligonucleotides. The antiviral potential of this element represents a promising start for further research into targeting conserved elements in RNA viruses.

Heavy metals are necessary at low concentration for biological activity, but they are often toxic for microorganisms at high concentrations. Amplicon sequencing of 16S rRNA and 18S rRNA was used to investigate changes in the bacterial and microeukaryotic communities in an activated sludge bioreactor incrementally contaminated with nickel (Ni), copper (Cu), and zinc (Zn) with an IC50 value ranging from 0% to 100%, as previously determined, while an uncontaminated bioreactor served as a control. The chemical oxygen demand (COD) was on average 90% in the uncontaminated bioreactor but dropped to 49% when the heavy metal concentration was 100% IC50. The bacterial community in the uncontaminated bioreactor was dominated by Alphaproteobacteria (mostly Agrobacterium and Brevundimonas) when the heavy metal concentrations were low and Bacteroidetes (mostly Sphingobacterium) when the highest amounts of heavy metal concentrations were applied. The members of Ciliophora, Ascomycota, and Basidiomycota alternatively dominated in the uncontaminated bioreactor, while Ascomycota (mostly Fusarium) dominated in the contaminated bioreactor. The results revealed that increased concentrations of Ni, Cu, and Zn altered the bacterial and microeukaryotic communities and some putative metabolic functions.

Abstract Reliable non-destructive methods for verifying spent nuclear fuel are essential to draw credible nuclear safeguards conclusions from spent fuel. In Finland, spent fuel items are verified prior to the soon starting disposal in a geological repository with Passive Gamma Emission Tomography (PGET), a uniquely accurate method capable of rod-level detection of missing active material. The PGET device consists of two highly collimated detector banks, collecting gamma emission data from a 360° rotation around a fuel assembly. 2D cross-sectional activity and attenuation images are simultaneously computed. We present methods for improving reconstructed image quality in the central parts of the fuel. The results are based on data collected from 2017 to 2021 at the Finnish nuclear power plants with 10 fuel assembly types of varying characteristics, for example burnups from 5.7 to 55 GWd/tU and cooling times from 1.9 to 37 years. Data is acquired in different gamma energy windows, capturing the peaks of Cs-137 (at 662 keV) and Eu-154 (at 1274 keV), abundant isotopes in long-cooled spent nuclear fuel. Data from these gamma energy windows at well-chosen angles are used for higher-quality images, resulting in more accurate detection of empty rod positions. The method is shown to detect partial diversion of nuclear material also in the axial direction, demonstrated with a novel measurement series scanning over the edge of partial-length rods.

Here, the authors develop a UV-compatible photonic integrated circuit for structured illumination microscopy on a conventional wide-field microscope. Operating at a wavelength of 360 nm, they generate switchable far-field fringe patterns, and demonstrate autofluorescence imaging of yeast cells.

Abstract Area selective atomic layer deposition (AS‐ALD) is an interesting bottom‐up approach due to its self‐aligned fabrication potential. Ruthenium dioxide (RuO2) is an important material for several applications, including microelectronics, demanding area selective processing. Herein, it is shown that ALD of RuO2 using methanol and RuO4 as reactants results in uninhibited continuous growth on SiO2, whereas there is no deposition on polymethyl methacrylate (PMMA) blanket films even up to 200 ALD cycles, resulting in around 25 nm of selective RuO2 deposition on SiO2. The excellent selectivity of the process is verified with X‐ray photoelectron spectroscopy, X‐ray fluorescence, and scanning transmission electron microscopy. AS‐ALD is possible at deposition temperatures as low as 60 °C, with an area selective window from 60 to 120 °C. The deposition of RuO2 using other coreactants namely ethanol and isopropanol in combination with RuO4 increases the process's growth rate while maintaining selectivity. Testing different polymer thin films such as poly(ethylene terephthalate glycol), (poly(lauryl methacrylate)‐co‐ethylene glycol dimethacrylate), polystyrene, and Kraton reveals an important relationship between polymer structure and the applicability of such polymers as mask layers. Finally, the developed method is demonstrated by selectively depositing RuO2 on patterned SiO2/PMMA samples, followed by PMMA removal, resulting in RuO2 nanopatterns.

The amount of nanoparticles that enters the environment has increased substantially in the last years. How they might affect plant characteristics and the bacterial community structure when they enter the soil, however, is still debated, as there is a continuous interaction between them. In this study, we determined the effect of silver (Ag-NPs) and hematite (α-Fe2O3-NPs) nanoparticles (0.15 g kg−1) on the characteristics of common bean (Phaseolus vulgaris L.) and the rhizosphere, non-rhizosphere and uncultivated soil bacterial community. The application of Ag-NPs or α-Fe2O3-NPs did not affect plant growth, but changed the amount of some heavy metals in the roots and aerial parts. The application of nanoparticles had a limited effect on the diversity, structure and functional profile of the soil and rhizosphere bacterial communities, but they were altered by cultivation of the bean plants and changed over time. It was found that application of Ag-NPs or α-Fe2O3-NPs had no effect on bean plant growth and only a small effect on the bacterial community structure and its putative metabolic functions. These findings show that in a complex system, such as a soil, different factors might affect the bacterial community structure and alter the possible effect of nanoparticles on it.

Electric-field-controlled magnetism can boost energy efficiency in widespread applications. However, technologically, this effect is facing important challenges: mechanical failure in strain-mediated piezoelectric/magnetostrictive devices, dearth of room-temperature multiferroics, or stringent thickness limitations in electrically charged metallic films. Voltage-driven ionic motion (magneto-ionics) circumvents most of these drawbacks while exhibiting interesting magnetoelectric phenomena. Nevertheless, magneto-ionics typically requires heat treatments and multicomponent heterostructures. Here we report on the electrolyte-gated and defect-mediated O and Co transport in a Co3O4 single layer which allows for room-temperature voltage-controlled ON-OFF ferromagnetism (magnetic switch) via internal reduction/oxidation processes. Negative voltages partially reduce Co3O4 to Co (ferromagnetism: ON), resulting in graded films including Co- and O-rich areas. Positive bias oxidizes Co back to Co3O4 (paramagnetism: OFF). This electric-field-induced atomic-scale reconfiguration process is compositionally, structurally, and magnetically reversible and self-sustained, since no oxygen source other than the Co3O4 itself is required. This process could lead to electric-field-controlled device concepts for spintronics.

With the widespread use of computed tomography (CT), subsolid nodules are more frequently encountered in daily practice. We present the case of a 74-year-old man with a large persistent well-defined subsolid nodule on CT. Although the lesion had a predominant ground-glass appearance on CT, 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) showed moderate FDG uptake. Lobectomy was performed and histopathologic examination showed an extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue. Teaching Point: When large persistent subsolid nodule with a predominant ground-glass aspect shows moderate uptake on 18F-FDG-PET, other possible diagnoses than adenocarcinoma should be kept in mind, including primary pulmonary lymphoma.

ABSTRACT Plant-associated microorganisms that affect plant development, their composition, and their functionality are determined by the host, soil conditions, and agricultural practices. How agricultural practices affect the rhizosphere microbiome has been well studied, but less is known about how they might affect plant endophytes. In this study, the metagenomic DNA from the rhizosphere and endophyte communities of root and stem of maize plants was extracted and sequenced with the “diversity arrays technology sequencing,” while the bacterial community and functionality (organized by subsystems from general to specific functions) were investigated in crops cultivated with or without tillage and with or without N fertilizer application. Tillage had a small significant effect on the bacterial community in the rhizosphere, but N fertilizer had a highly significant effect on the roots, but not on the rhizosphere or stem. The relative abundance of many bacterial species was significantly different in the roots and stem of fertilized maize plants, but not in the unfertilized ones. The abundance of N cycle genes was affected by N fertilization application, most accentuated in the roots. How these changes in bacterial composition and N genes composition might affect plant development or crop yields has still to be unraveled. IMPORTANCE We investigated the bacterial community structure in the rhizosphere, root, and stem of maize plants cultivated under different agricultural techniques, i.e., with or without N fertilization, and with or without tillage. We found that the bacterial community was defined mostly by the plant compartment and less by agricultural techniques. In the roots, N fertilizer application affected the bacterial community structure, the microbiome functionality, and the abundance of genes involved in the N cycle, but the effect in the rhizosphere and stem was much smaller. Contrary, tillage did not affect the maize microbiome. This study enriches our knowledge about the plant-microbiome system and how N fertilization application affected it.

Hemophagocytic lymphohistiocytosis may occur in patients with genetic predisposition and in sporadic cases due to malignancy or infection. We describe a 49-year old man with hemorrhagic fever, type 1 respiratory insufficiency and acute kidney injury. Diagnostic work up showed a hyperinflammatory syndrome, hypertriglyceridemia, hemophagocytosis, very high ferritin and significantly elevated sCD25. The findings were compatible with hemophagocytic lymphohistiocytosis based on the HLH-2004 criteria. Serological testing indentified Puumala virus as the causal pathogen. The patient was successfully treated with pulse corticosteroids, intravenous immunoglobins and supportive therapy.

A modified method for the direct extraction of DNA from alkaline-saline soils with minimum DNA fragmentation and a possible reduction in chimera formation during polymerase chain reaction (PCR) was developed. The commercial extraction kit Power Soil DNA (Mo Bio™ Laboratories, Inc.) was used as a reference technique. The method reported here was based on cell lysis employing ethylenediaminetetraacetic acid (EDTA), sodium dodecyl sulfate (SDS), and cell disruption with mechanical force with FastPrep-24™ equip followed by one cycle of freezing at -40 °C for 60 min and thawing at 65 °C for 20 min. The extraction method was tested for allophonic soils with large concentrations of organic matter, fulvic and humic acids, electrolytic conductivity (EC) ranging between 2.6 dS m-1 and 39.9 dS m-1, and pH between 8.8 and 10.9. The yield of DNA extracted depended on soil type, i.e., DNA extracted from soil varied between 2.35 (Texcoco-2) to 3.66 (Texcoco-1) μg DNA g-1 soil. The proposed method in this study produced enough DNA with yield and quality for PCR amplification of 16S rDNA when bovine serum albumin (BSA) was added to the reaction buffer. The DNA obtained had sufficient quality and yield for later use for 16S sequencing or possible use in other sequencing technologies, e.g. whole metagenome shotgun sequencing.

Summary: Background: The present study aimed to evaluate the persistent immunogenicity offered by a third dose of BNT162b2 against Delta and Omicron variants, in nursing home (NH) residents. Methods: In this monocenter prospective observational study, anti-spike IgG levels, S1 domain reactive T cell counts, serum neutralizing antibody titers against Delta and Omicron variants were compared before and up to three months after the BNT162b2 booster dose, in NH residents without COVID-19 (COVID-19 naive) or with COVID-19 prior to initial vaccination (COVID-19 recovered). Findings: 106 NH residents (median [interquartile range] age: 86·5 [81;91] years) were included. The booster dose induced a high increase of anti-spike antibody levels in all subjects (p

Abstract Background Kidney biopsy registries all over the world benefit research, teaching and health policy. Comparison, aggregation and exchange of data is however greatly dependent on how registration and coding of kidney biopsy diagnoses are performed. This paper gives an overview over kidney biopsy registries, explores how these registries code kidney disease and identifies needs for improvement of coding practice. Methods A literature search was undertaken to identify biopsy registries for medical kidney diseases. These data were supplemented with information from personal contacts and from registry websites. A questionnaire was sent to all identified registries, investigating age of registries, scope, method of coding, possible mapping to international terminologies as well as self-reported problems and suggestions for improvement. Results Sixteen regional or national kidney biopsy registries were identified, of which 11 were older than 10 years. Most registries were located either in Europe (10/16) or in Asia (4/16). Registries most often use a proprietary coding system (12/16). Only a few of these coding systems were mapped to SNOMED CT (1), older SNOMED versions (2) or ERA-EDTA PRD (3). Lack of maintenance and updates of the coding system was the most commonly reported problem. Conclusions There were large gaps in the global coverage of kidney biopsy registries. Limited use of international coding systems among existing registries hampers interoperability and exchange of data. The study underlines that the use of a common and uniform coding system is necessary to fully realize the potential of kidney biopsy registries.

ABSTRACT Farmers in Mexico till soil intensively, remove crop residues for fodder and grow maize often in monoculture. Conservation agriculture (CA), including minimal tillage, crop residue retention and crop diversification, is proposed as a more sustainable alternative. In this study, we determined the effect of agricultural practices and the developing maize rhizosphere on soil bacterial communities. Bulk and maize (Zea mays L.) rhizosphere soil under conventional practices (CP) and CA were sampled during the vegetative, flowering and grain filling stage, and 16S rRNA metabarcoding was used to assess bacterial diversity and community structure. The functional diversity was inferred from the bacterial taxa using PICRUSt. Conservation agriculture positively affected taxonomic and functional diversity compared to CP. The agricultural practice was the most important factor in defining the structure of bacterial communities, even more so than rhizosphere and plant growth stage. The rhizosphere enriched fast growing copiotrophic bacteria, such as Rhizobiales, Sphingomonadales, Xanthomonadales, and Burkholderiales, while in the bulk soil of CP other copiotrophs were enriched, e.g., Halomonas and Bacillus. The bacterial community in the maize bulk soil resembled each other more than in the rhizosphere of CA and CP. The bacterial community structure, and taxonomic and functional diversity in the maize rhizosphere changed with maize development and the differences between the bulk soil and the rhizosphere were more accentuated when the plant aged. Although agricultural practices did not alter the effect of the rhizosphere on the soil bacterial communities in the flowering and grain filling stage, they did in the vegetative stage. IMPORTANCE We studied the effect of sustainable conservation agricultural practices versus intensive conventional ones on the soil microbial diversity, potential functionality, and community assembly in rhizosphere of maize cultivated in a semiarid environment. We found that conservation agriculture practices increased the diversity of soil microbial species and functions and strongly affected how they were structured compared to conventional practices. Microbes affected by the roots of maize, the rhizobiome, were different and more diverse than in the surrounding soil and their diversity increased when the plant grew. The agricultural practices affected the maize rhizobiome only in the early stages of growth, but this might have an important impact on the development of maize plant.