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Ageing is associated with decreased physical activity, obesity and increased risk of hypertension (HTN). Master athletes (MA) have either pursued a physically active lifestyle throughout their life or initiated exercise or sport later in life. We assessed resting blood pressure (BP) in male and female World Masters Games (WMG) athletes. This was a cross-sectional, observational study which utilized an online survey to assess the blood pressure (BP) and other physiological parameters. Results: a total of 2793 participants were involved in this study. Key findings included differences between genders with males reporting higher resting SBP (+9.4%, p < 0.001), resting DBP (+5.9%, p < 0.001) and mean arterial pressure (+6.2%, p < 0.001). Significant differences (p < 0.001) were also identified when comparing WMG athletes’ resting BP results (genders combined) to the general Australian population with WMG athletes having a lower SBP (p < 0.001, −8.4%) and DBP (p < 0.001, −3.6%). Additionally, 19.9% of males and 49.7% of female WMG participants were normotensive whereas 35.7% of the general Australian population were normotensive. Only 8.1% of the WMG athletes (genders combined) were found to be HTN compared to 17.2% in the general Australian population. These findings reflect a low prevalence of HTN in WMG participants and support our hypothesis of a low prevalence of HTN in an active, but aged cohort of MA.

Background Ageing is associated with decreased physical activity, obesity and subsequently an increased risk of developing type 2 diabetes mellitus (T2dm). Master athletes (MA) have initiated exercise or sport later in life or pursued a physically active lifestyle for an extended period. Subsequently, MAs have been proposed as a model of successful ageing as this active lifestyle is associated with health benefits including decreased health risk of chronic diseases and a reduction in premature mortality. Given long-term physical activity/exercise has previously been shown to be protective against hyperglycemia, a risk factor for T2dm, it is plausible that MA may have protective benefit against developing hyperglycemia. Therefore, the aim of this study was to investigate the prevalence of hyperglycemia via fasting plasma glucose (FPG) in MAs competing at the World Masters Games (WMG). Methods This cross-sectional, observational survey utilized an online survey using open-source web-based software was used to investigate MAs physiological and medical-related parameters. Over 28,000 MAs competed in the WMG, of which 8,072 MAs completed the survey. Of these MAs, a total of 486 (males 277, females 209; range 27 to 91 years, mean age 55.1 ± 10.2 years) attained recent pathology results which included FPG which was subsequently analyzed for this study. FPG and other outcome variables were compared between genders and to the Australian and United States general population. Results Mean FPG for MAs was 5.03 mmol (±1.2, 95% CI [4.9–5.1] mmol) with majority (75.5%) of MAs reporting a normal (5.51 to 7.0 mmol). There was no significant difference (P = 0.333) in FPG between genders however, males had a slightly higher (+2.1%) FPG as compared to females (5.08 ± 1.2 mmol (95% CI [4.9–5.22] mmol) versus 4.98 ± 1.1 mmol (95% CI 4.8-5.1 mmol)). The majority of males (71.8%) and females (80.3%) were classified with a normal FPG. With regard to an abnormal FPG level, only 4.0% of males and 4.9% of females were classified abnormal which was suggestive of undiagnosed T2dm. With regard to age by decade, there was no significant difference (P = 0.06–1.00) between age groups and no relationship between the MAs’ age and FPG (r = .054, P = 0.24). As a group, MAs had a significantly lower FPG as compared to the Australian (−3.2%, P = 0.005) and United States general populations (−13.9%, P < 0.001). Conclusions Most, however not all, MAs were found to have normal glycaemia, with only a small percentage indicating a risk of developing T2dm (i.e., impaired fasting glucose) and a smaller percentage identified with an abnormal FPG, suggestive of T2dm. These findings suggest MAs appear to be at low metabolic risk for developing T2dm based upon FPG and the physical activity/exercise they complete as MAs may indeed be protective against hyperglycemia whilst maintaining an active lifestyle.

Understanding the nexus between aging, physical activity, and obesity has been a source of ongoing investigation. A considerable amount of research has focused on Masters athletes in this regard, suggesting a beneficial relationship between Masters sport participation and a healthy body mass index (BMI). Some consider Active Duty military personnel as tactical athletes. As such, it is of interest to determine if aging Active Duty military personnel (or Masters Tactical Athletes) might have a similar BMI as other Masters athletes (MA). As such, this investigation examined previously recorded data of Active Duty Enlisted United States Marines (n = 402, male, 46–50 years old). The BMI of the Marines was stratified into categories of: underweight, normal, overweight, and obese. The Marines obesity prevalence was compared to US adult males (40–59 years) as well as male North American MA who competed at the 2009 Sydney World Masters Games. The Marines obesity prevalence was significantly lower than US adult males (p < 0.001) and those MA that competed in softball (p < 0.001); however, it was similar to MA that competed in football, track/field, swimming, and volleyball (p > 0.05). The average Marine BMI = 26.7 kg/m2 was similar to MA who competed in football, swimming, and volley ball (p > 0.05); however, it was higher than MA who competed in track/field (p < 0.05) and lower than MA who played softball (p < 0.05). It should be noted that the average BMI for the Marines and all MA sport categories were classified as being overweight. Within the parameters of this investigation, Tactical MA (i.e., aging US Marines) enjoy a similar beneficial BMI as other North American MA.

A complete understanding of RNA biology requires methods for tracking transcripts in vivo. Common strategies rely on fluorogenic probes that are limited in sensitivity, dynamic range, and depth of interrogation, owing to their need for excitation light and tissue autofluorescence. To overcome these challenges, we report a bioluminescent platform for serial imaging of RNAs. The RNA tags are engineered to recruit light-emitting luciferase fragments (termed RNA lanterns) upon transcription. Robust photon production is observed for RNA targets both in cells and in live animals. Importantly, only a single copy of the tag is necessary for sensitive detection, in sharp contrast to fluorescent platforms requiring multiple repeats. Overall, this work provides a foundational platform for visualizing RNA dynamics from the micro to the macro scale., Competing Interests: Competing interests A.L., J.A.P., O.S., K.K.N., K.H.C., L.P.H., and C.C.C. are on a provisional patent application, filed through UCI, based on the results described here. The remaining authors declare no competing interests., (© 2024. The Author(s).)

Metal-insulator transitions (MITs) in resistive switching materials can be triggered by an electric stimulus that produces significant changes in the electrical response. When these phases have distinct magnetic characteristics, dramatic changes in the spin excitations are also expected. The transition metal oxide La 0.7 Sr 0.3 MnO 3 (LSMO) is a ferromagnetic metal at low temperatures and a paramagnetic insulator above room temperature. When LSMO is in its metallic phase, a critical electrical bias has been shown to lead to an MIT that results in the formation of a paramagnetic resistive barrier transverse to the applied electric field. Using spin-transfer ferromagnetic resonance spectroscopy, we show that even for electrical biases less than the critical value that triggers the MIT, there is magnetic phase separation, with the spin-excitation resonances varying systematically with applied bias. Therefore, voltage-triggered MITs in LSMO can alter magnetic resonance characteristics, offering an effective method for tuning synaptic weights in neuromorphic circuits.

Ectomycorrhizal (EM) associations can promote the dominance of tree species in otherwise diverse tropical forests. These EM associations between trees and their fungal mutualists have important consequences for soil organic matter cycling, yet the influence of these EM-associated effects on surrounding microbial communities is not well known, particularly in neotropical forests. We examined fungal and prokaryotic community composition in surface soil samples from mixed arbuscular mycorrhizal (AM) and ectomycorrhizal (EM) stands as well as stands dominated by EM-associated Oreomunnea mexicana (Juglandaceae) in four watersheds differing in soil fertility in the Fortuna Forest Reserve, Panama. We hypothesized that EM-dominated stands would support distinct microbial community assemblages relative to the mixed AM-EM stands due to differences in carbon and nitrogen cycling associated with the dominance of EM trees. We expected that this microbiome selection in EM-dominated stands would lead to lower overall microbial community diversity and turnover, with tighter correspondence between general fungal and prokaryotic communities. We measured fungal and prokaryotic community composition via high-throughput Illumina sequencing of the ITS2 (fungi) and 16S rRNA (prokaryotic) gene regions. We analyzed differences in alpha and beta diversity between forest stands associated with different mycorrhizal types, as well as the relative abundance of fungal functional groups and various microbial taxa. We found that fungal and prokaryotic community composition differed based on stand mycorrhizal type. There was lower prokaryotic diversity and lower relative abundance of fungal saprotrophs and pathogens in EM-dominated than AM-EM mixed stands. However, contrary to our prediction, there was lower homogeneity for fungal communities in EM-dominated stands compared to mixed AM-EM stands. Overall, we demonstrate that EM-dominated tropical forest stands have distinct soil microbiomes relative to surrounding diverse forests, suggesting that EM fungi may filter microbial functional groups in ways that could potentially influence plant performance or ecosystem function., (© 2024. The Author(s).)

Background: Microbiome recruitment is influenced by plant host, but how host plant impacts the assembly, functions, and interactions of perennial plant root microbiomes is poorly understood. Here we examined prokaryotic and fungal communities between rhizosphere soils and the root endophytic compartment in two native Miscanthus species (Miscanthus sinensis and Miscanthus floridulus) of Taiwan and further explored the roles of host plant on root-associated microbiomes., Results: Our results suggest that host plant genetic variation, edaphic factors, and site had effects on the root endophytic and rhizosphere soil microbial community compositions in both Miscanthus sinensis and Miscanthus floridulus, with a greater effect of plant genetic variation observed for the root endophytic communities. Host plant genetic variation also exerted a stronger effect on core prokaryotic communities than on non-core prokaryotic communities in each microhabitat of two Miscanthus species. From rhizosphere soils to root endophytes, prokaryotic co-occurrence network stability increased, but fungal co-occurrence network stability decreased. Furthermore, we found root endophytic microbial communities in two Miscanthus species were more strongly driven by deterministic processes rather than stochastic processes. Root-enriched prokaryotic OTUs belong to Gammaproteobacteria, Alphaproteobacteria, Betaproteobacteria, Sphingobacteriia, and [Saprospirae] both in two Miscanthus species, while prokaryotic taxa enriched in the rhizosphere soil are widely distributed among different phyla., Conclusions: We provide empirical evidence that host genetic variation plays important roles in root-associated microbiome in Miscanthus. The results of this study have implications for future bioenergy crop management by providing baseline data to inform translational research to harness the plant microbiome to sustainably increase agriculture productivity. Video Abstract., (© 2023. BioMed Central Ltd., part of Springer Nature.)

The brain has effectively proven a powerful inspiration for the development of computing architectures in which processing is tightly integrated with memory, communication is event-driven, and analog computation can be performed at scale. These neuromorphic systems increasingly show an ability to improve the efficiency and speed of scientific computing and artificial intelligence applications. Herein, it is proposed that the brain's ubiquitous stochasticity represents an additional source of inspiration for expanding the reach of neuromorphic computing to probabilistic applications. To date, many efforts exploring probabilistic computing have focused primarily on one scale of the microelectronics stack, such as implementing probabilistic algorithms on deterministic hardware or developing probabilistic devices and circuits with the expectation that they will be leveraged by eventual probabilistic architectures. A co-design vision is described by which large numbers of devices, such as magnetic tunnel junctions and tunnel diodes, can be operated in a stochastic regime and incorporated into a scalable neuromorphic architecture that can impact a number of probabilistic computing applications, such as Monte Carlo simulations and Bayesian neural networks. Finally, a framework is presented to categorize increasingly advanced hardware-based probabilistic computing technologies., (© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Ultra-thin films of low damping ferromagnetic insulators with perpendicular magnetic anisotropy have been identified as critical to advancing spin-based electronics by significantly reducing the threshold for current-induced magnetization switching while enabling new types of hybrid structures or devices. Here, we have developed a new class of ultra-thin spinel structure Li 0.5 Al 1.0 Fe 1.5 O 4 (LAFO) films on MgGa 2 O 4 (MGO) substrates with: 1) perpendicular magnetic anisotropy; 2) low magnetic damping and 3) the absence of degraded or magnetic dead layers. These films have been integrated with epitaxial Pt spin source layers to demonstrate record low magnetization switching currents and high spin-orbit torque efficiencies. These LAFO films on MGO thus combine all of the desirable properties of ferromagnetic insulators with perpendicular magnetic anisotropy, opening new possibilities for spin based electronics., (© 2023. Springer Nature Limited.)

Spin-Hall nano-oscillators (SHNOs) are promising spintronic devices to realize current controlled GHz frequency signals in nanoscale devices for neuromorphic computing and creating Ising systems. However, traditional SHNOs devices based on transition metals have high auto-oscillation threshold currents as well as low quality factors and output powers. Here we demonstrate a new type of hybrid SHNO based on a permalloy (Py) ferromagnetic-metal nanowire and low-damping ferrimagnetic insulator, in the form of epitaxial lithium aluminum ferrite (LAFO) thin films. The superior characteristics of such SHNOs are associated with the excitation of larger spin-precession angles and volumes. We further find that the presence of the ferrimagnetic insulator enhances the auto-oscillation amplitude of spin-wave edge modes, consistent with our micromagnetic modeling. This hybrid SHNO expands spintronic applications, including providing new means of coupling multiple SHNOs for neuromorphic computing and advancing magnonics., (© 2023. The Author(s).)

While large inputs of synthetic nitrogen fertilizers enable our current rate of crop production and feed a growing global population, these fertilizers come at a heavy environmental cost. Driven by microbial processes, excess applied nitrogen is lost from agroecosystems as nitrate and nitrous oxide (N 2 O) contaminating aquatic ecosystems and contributing to climate change. Interest in nitrogen-fixing microorganisms as an alternative to synthetic fertilizers is rapidly accelerating. Microbial inoculants offer the promise of a sustainable and affordable source of nitrogen, but the impact of inoculants on nitrogen dynamics at an ecosystem level is not fully understood. This review synthesizes recent studies on microbial inoculants as tools for nutrient management and considers the ramifications of inoculants for nitrogen transformations beyond fixation., Competing Interests: Declaration of interests No interests are declared., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The recent discoveries of two-dimensional (2D) magnets 1-6 and their stacking into van der Waals structures 7-11 have expanded the horizon of 2D phenomena. One exciting application is to exploit coherent magnons 12 as energy-efficient information carriers in spintronics and magnonics 13,14 or as interconnects in hybrid quantum systems 15-17 . A particular opportunity arises when a 2D magnet is also a semiconductor, as reported recently for CrSBr (refs. 18-20 ) and NiPS 3 (refs. 21-23 ) that feature both tightly bound excitons with a large oscillator strength and potentially long-lived coherent magnons owing to the bandgap and spatial confinement. Although magnons and excitons are energetically mismatched by orders of magnitude, their coupling can lead to efficient optical access to spin information. Here we report strong magnon-exciton coupling in the 2D A-type antiferromagnetic semiconductor CrSBr. Coherent magnons launched by above-gap excitation modulate the exciton energies. Time-resolved exciton sensing reveals magnons that can coherently travel beyond seven micrometres, with a coherence time of above five nanoseconds. We observe these exciton-coupled coherent magnons in both even and odd numbers of layers, with and without compensated magnetization, down to the bilayer limit. Given the versatility of van der Waals heterostructures, these coherent 2D magnons may be a basis for optically accessible spintronics, magnonics and quantum interconnects., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Skyrmion racetrack memories are highly attractive for next-generation data storage technologies. Skyrmions are noncollinear spin textures stabilized by chiral interactions. To achieve a fast-operating memory device, it is critical to move skyrmions at high speeds. The skyrmion dynamics induced by spin-orbit torques (SOTs) in the commonly studied ferromagnetic films is hindered by strong pinning effects and a large skyrmion Hall effect causing deflection of the skyrmion toward the racetrack edge, which can lead to information loss. Here, we investigate the current-induced nucleation and motion of skyrmions in ferrimagnetic Pt/CoGd/(W or Ta) thin films. We first reveal field-free skyrmion nucleation mediated by Joule heating. We then achieve fast skyrmion motion driven by SOTs with velocities as high as 610 m s -1 and a small skyrmion Hall angle |θ SkHE | ≲ 3°. Our results show that ferrimagnets are better candidates for fast skyrmion-based memory devices with low risk of information loss.

Alder (Alnus spp.) and Pacific salmon (Oncorhynchus spp.) provide key nutrient subsidies to freshwater systems. In southwestern Alaska, alder-derived nutrients (ADNs) are increasing as alder cover expands in response to climate warming, while climate change and habitat degradation are reducing marine-derived nutrients (MDNs) in salmon-spawning habitats. To assess the relative influences of ADN and MDN on aquatic microbial community structure and function, we analyzed lake chemistry, bacterial community structure, and microbial metabolism in 13 lakes with varying alder cover and salmon abundance in southwestern Alaska. We conducted bioassays to determine microbial nutrient limitation and physical factors modulating microbial response to nutrient inputs (+N, +P and +NP treatments). Seasonal shifts in bacterial community structure (F = 7.47, P < 0.01) coincided with changes in lake nitrogen (N) and phosphorus (P) concentrations (r 2  = 0.19 and 0.16, both P < 0.05), and putrescine degradation (r 2  = 0.13, P = 0.06), suggesting the influx and microbial use of MDN. Higher microbial metabolism occurred in summer than spring, coinciding with salmon runs. Increased microbial metabolism occurred in lakes where more salmon spawned. Microbial metabolic activity was unrelated to alder cover, likely because ADN provides less resource diversity than MDN. When nutrients were added to spring samples, there was greater substrate use by microbial communities from lakes with elevated Chl a concentrations and large relative catchment areas (β estimates for all treatments > 0.56, all P < 0.07). Thus, physical watershed and lake features mediate the effects of nutrient subsidies on aquatic microbial metabolic activity., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Electrical switching of antiferromagnets is an exciting recent development in spintronics, which promises active antiferromagnetic devices with high speed and low energy cost. In this emerging field, there is an active debate about the mechanisms of current-driven switching of antiferromagnets. For heavy-metal/ferromagnet systems, harmonic characterization is a powerful tool to quantify current-induced spin-orbit torques and spin Seebeck effect and elucidate current-induced switching. However, harmonic measurement of spin-orbit torques has never been verified in antiferromagnetic heterostructures. Here, we report harmonic measurements in Pt/α-Fe 2 O 3 bilayers, which are explained by our modeling of higher-order harmonic voltages. As compared with ferromagnetic heterostructures where all current-induced effects appear in the second harmonic signals, the damping-like torque and thermally-induced magnetoelastic effect contributions in Pt/α-Fe 2 O 3 emerge in the third harmonic voltage. Our results provide a new path to probe the current-induced magnetization dynamics in antiferromagnets, promoting the application of antiferromagnetic spintronic devices., (© 2022. The Author(s).)

The effect of spin currents on the magnetic order of insulating antiferromagnets (AFMs) is of fundamental interest and can enable new applications. Toward this goal, characterizing the spin-orbit torques (SOTs) associated with AFM-heavy-metal (HM) interfaces is important. Here we report the full angular dependence of the harmonic Hall voltages in a predominantly easy-plane AFM, epitaxial c-axis oriented α-Fe&#95;{2}O&#95;{3} films, with an interface to Pt. By modeling the harmonic Hall signals together with the α-Fe&#95;{2}O&#95;{3} magnetic parameters, we determine the amplitudes of fieldlike and dampinglike SOTs. Out-of-plane field scans are shown to be essential to determining the dampinglike component of the torques. In contrast to ferromagnetic-heavy-metal heterostructures, our results demonstrate that the fieldlike torques are significantly larger than the dampinglike torques, which we correlate with the presence of a large imaginary component of the interface spin-mixing conductance. Our work demonstrates a direct way of characterizing SOTs in AFM-HM heterostructures.

Background: Assessments of the soil microbiome provide valuable insight to ecosystem function due to the integral role microorganisms play in biogeochemical cycling of carbon and nutrients. For example, treatment effects on nitrogen cycling functional groups are often presented alongside one another to demonstrate how agricultural management practices affect various nitrogen cycling processes. However, the functional groups commonly evaluated in nitrogen cycling microbiome studies range from phylogenetically narrow (e.g., N-fixation, nitrification) to broad [e.g., denitrification, dissimilatory nitrate reduction to ammonium (DNRA)]. The bioinformatics methods used in such studies were developed for 16S rRNA gene sequence data, and how these tools perform across functional genes of different phylogenetic diversity has not been established. For example, an OTU clustering method that can accurately characterize sequences harboring comparatively little diversity may not accurately resolve the diversity within a gene comprised of a large number of clades. This study uses two nitrogen cycling genes, nifH , a gene which segregates into only three distinct clades, and nrfA , a gene which is comprised of at least eighteen clades, to investigate differences which may arise when using heuristic OTU clustering (abundance-based greedy clustering, AGC) vs. true hierarchical OTU clustering (Matthews Correlation Coefficient optimizing algorithm, Opti-MCC). Detection of treatment differences for each gene were evaluated to demonstrate how conclusions drawn from a given dataset may differ depending on clustering method used., Results: The heuristic and hierarchical methods performed comparably for the more conserved gene, nifH . The hierarchical method outperformed the heuristic method for the more diverse gene, nrfA ; this included both the ability to detect treatment differences using PERMANOVA, as well as higher resolution in taxonomic classification. The difference in performance between the two methods may be traced to the AGC method's preferential assignment of sequences to the most abundant OTUs: when analysis was limited to only the largest 100 OTUs, results from the AGC-assembled OTU table more closely resembled those of the Opti-MCC OTU table. Additionally, both AGC and Opti-MCC OTU tables detected comparable treatment differences using the rank-based ANOSIM test. This demonstrates that treatment differences were preserved using both clustering methods but were structured differently within the OTU tables produced using each method., Conclusion: For questions which can be answered using tests agnostic to clustering method (e.g., ANOSIM), or for genes of relatively low phylogenetic diversity (e.g., nifH ), most upstream processing methods should lead to similar conclusions from downstream analyses. For studies involving more diverse genes, however, care should be exercised to choose methods that ensure accurate clustering for all genes. This will mitigate the risk of introducing Type II errors by allowing for detection of comparable treatment differences for all genes assessed, rather than disproportionately detecting treatment differences in only low-diversity genes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Egenriether, Sanford, Yang and Kent.)

Belowground, plants interact with beneficial soil microbes such as plant growth-promoting rhizobacteria (PGPR). PGPR are rhizosphere bacteria that colonize roots and elicit beneficial effects in plants such as improved plant growth, pathogen resistance, abiotic stress tolerance, and herbivore protection. Treatment of plants with PGPR has been shown to trigger the emission of volatile organic compounds (VOCs). Volatile emissions can also be triggered by herbivory, termed herbivore-induced plant volatiles (HIPV), with important ramifications for chemical-mediated plant and insect interactions. Much of our current understanding of PGPR and herbivore-induced volatiles is based on studies using one plant genotype, yet domestication and modern breeding has led to the development of diverse germplasm with altered phenotypes and chemistry. In this study, we investigated if volatile emissions triggered by PGPR colonization and herbivory varies by maize genotype and microbial community assemblages. Six maize genotypes representing three decades of crop breeding and two heterotic groups were used, with four microbiome treatments: live or sterilized soil, with or without a Bacillus inoculant. Soil sterilization was used to delay microbiome establishment, resulting in low-diversity treatments. At planting, maize seeds were inoculated with PGPR Bacillus altitudinis AP-283 and grown under greenhouse conditions. Four weeks post planting, plants were subjected to feeding by third instar Helicoverpa zea (Lepidoptera: Noctuidae) larvae. Volatiles were collected using solid phase microextraction and analyzed with gas chromatography-mass spectrometry. Illumina NovaSeq 16S rRNA amplicon sequencing was carried out to characterize the rhizosphere microbiome. Maize genotype significantly influenced total volatile emissions, and relative abundance of volatile classes. We did not document a strong influence of microbe treatment on plant VOC emissions. However, inoculating plants with PGPR improved plant growth under sterile conditions. Taken together, our results suggest that genotypic variation is the dominant driver in HIPV composition and individual HIPV abundances, and any bacterial-mediated benefit is genotype and HIPV-specific. Therefore, understanding the interplay of these factors is necessary to fully harness microbially-mediated benefits and improve agricultural sustainability., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Raglin, Kent and Ngumbi.)