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Recent field campaigns, observational studies, and modeling work have demonstrated that extratropical tropopause-overshooting convection has a substantial and previously underestimated impact on stratospheric water vapor concentrations. This necessitates improved understanding of how tropopause-overshooting convection will respond to a warming climate. A growing body of research indicates that environments conducive to severe thunderstorms will occur more often and be increasingly unstable in the future, but no study has examined how this may be related to increased overshooting. To rectify this, this study leverages an existing pseudo–global warming (PGW) experiment to evaluate potential future changes in tropopause-overshooting convection over North America. We examine two 10-yr simulations consisting of 1) a retrospective period (2003–12) forced by ERA-Interim initial and boundary conditions (the control simulation) and 2) the same retrospective period with CMIP5 ensemble-mean high-end emission scenario climate changes added to the initial and boundary conditions (the PGW simulation). Tropopause-overshooting convection in the control simulation is validated against observed overshoots from both ground-based radar observations in the United States and GOES observations over North America. The model is shown to effectively simulate the observed regional distribution, annual cycle, and diurnal cycle of tropopause-overshooting convection. In the PGW simulation, tropopause-overshooting convection is found to increase more than 250% across the model domain, and the projected seasonal period of frequent tropopause-overshooting convection is shown to extend into late summer. Additionally, tropopause-overshooting convection with extreme tropopause-relative heights (>4 km) is more frequent in a warmed climate scenario. [ABSTRACT FROM AUTHOR]

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes Coronavirus Disease 2019 (COVID-19), which can result in severe disease, often characterised by a 'cytokine storm' and the associated acute respiratory distress syndrome. However, many infections with SARS-CoV-2 are mild or asymptomatic throughout the course of infection. Although blood biomarkers of severe disease are well studied, less well understood are the inflammatory signatures in lung tissues associated with mild disease or silent infections, wherein infection and inflammation are rapidly resolved leading to sequelae-free recovery. Herein we described RNA-Seq and histological analyses of lungs over time in an omicron BA.1/K18-hACE2 mouse infection model, which displays these latter features. Although robust infection was evident at 2 days post infection (dpi), viral RNA was largely cleared by 10 dpi. Acute inflammatory signatures showed a slightly different pattern of cytokine signatures compared with severe infection models, and where much diminished 30 dpi and absent by 66 dpi. Cellular deconvolution identified significantly increased abundance scores for a number of anti-inflammatory pro-resolution cell types at 5/10 dpi. These included type II innate lymphoid cells, T regulatory cells, and interstitial macrophages. Genes whose expression trended downwards over 2–66 dpi included biomarkers of severe disease and were associated with 'cytokine storm' pathways. Genes whose expression trended upward during this period were associated with recovery of ciliated cells, AT2 to AT1 transition, reticular fibroblasts and innate lymphoid cells, indicating a return to homeostasis. Very few differentially expressed host genes were identified at 66 dpi, suggesting near complete recovery. The parallels between mild or subclinical infections in humans and those observed in this BA.1/K18-hACE2 mouse model are discussed with reference to the concept of "protective inflammation". [ABSTRACT FROM AUTHOR]

The Disease Transmission Advisory Committee (DTAC) of the Organ Procurement and Transplantation Network focuses on issues related to the transmission of disease through organ transplantation. Providing a review of potential cases of transmission, translating aggregate data into actionable education and guidance for the transplant community, and providing input for policy development, DTAC aims to improve the safety of organ transplantation through a reduction in donor‐derived transmission events. Through its nearly 20‐year history, DTAC has provided education, guidance, and policy, addressed numerous emerging infections, and continuously focused on the community's understanding of risk assessment related to donor‐derived transmission. By updating the DTAC mission to both decrease transmission and safely expand the donor pool with additional guidance to safely use organs previously not considered for transplantation due to transmission concerns, the Committee's role will remain critical. [ABSTRACT FROM AUTHOR]

Context. The difference between individual solar cycles in the magnetic butterfly diagram can mostly be ascribed to the stochasticity of the emergence process. Aims. We aim to obtain the expectation value of the butterfly diagram from observations of four cycles. This allows us to further determine the generation rate of the surface radial magnetic field. Methods. We used data from Wilcox Solar Observatory to generate time-latitude diagrams of the surface radial and toroidal magnetic fields spanning cycles 21–24. We symmetrized them across the equator and cycle-averaged them. From the mean butterfly diagram and surface toroidal field, we then inferred the mean poloidal field generation rate at the surface of the Sun. Results. The averaging procedure removes realization noise from individual cycles. The amount of emerging flux required to account for the evolution of the surface radial field is found to match that provided by the observed surface toroidal field and Joy's law. Conclusions. Cycle-averaging butterfly diagrams removes realization noise and artefacts due to imperfect scale separation and corresponds to an ensemble average that can be interpreted in the mean-field framework. The result can then be directly compared to αΩ-type dynamo models. The Babcock-Leighton α-effect is consistent with observations, a result that can be appreciated only if the observational data are averaged in some way. [ABSTRACT FROM AUTHOR]

Contemporary injury tolerance of the lumbar spine for under-body blast references axial compression and bending moments in a limited range. Since injuries often occur in a wider range of flexion and extension with increased moment contribution, this study expands a previously proposed combined loading injury criterion for the lumbar spine. Fifteen cadaveric lumbar spine failure tests with greater magnitudes of eccentric loading were incorporated into an existing injury criterion to augment its applicability and a combined loading injury risk model was proposed by means of survival analysis. A loglogistic distribution was the most representative of injury risk, resulting in optimized critical values of Fr,crit = 6011 N, and My,crit = 904 Nm for the proposed combined loading metric. The 50% probability of injury resulted in a combined loading metric value of 1, with 0.59 and 1.7 corresponding to 5 and 95% injury risk, respectively. The inclusion of eccentric loaded specimens resulted in an increased contribution of the bending moment relative to the previously investigated flexion/extension range (previous My,crit = 1155 Nm), with the contribution of the resultant sagittal force reduced by nearly 200 N (previous Fr,crit = 5824 N). The new critical values reflect an expanded flexion/extension range of applicability of the previously proposed combined loading injury criterion for the human lumbar spine during dynamic compression. [ABSTRACT FROM AUTHOR]

Public gene expression databases are a rapidly expanding resource of organism responses to diverse perturbations, presenting both an opportunity and a challenge for bioinformatics workflows to extract actionable knowledge of transcription regulatory network function. Here, we introduce a five-step computational pipeline, called iModulonMiner, to compile, process, curate, analyze, and characterize the totality of RNA-seq data for a given organism or cell type. This workflow is centered around the data-driven computation of co-regulated gene sets using Independent Component Analysis, called iModulons, which have been shown to have broad applications. As a demonstration, we applied this workflow to generate the iModulon structure of Bacillus subtilis using all high-quality, publicly-available RNA-seq data. Using this structure, we predicted regulatory interactions for multiple transcription factors, identified groups of co-expressed genes that are putatively regulated by undiscovered transcription factors, and predicted properties of a recently discovered single-subunit phage RNA polymerase. We also present a Python package, PyModulon, with functions to characterize, visualize, and explore computed iModulons. The pipeline, available at https://github.com/SBRG/iModulonMiner, can be readily applied to diverse organisms to gain a rapid understanding of their transcriptional regulatory network structure and condition-specific activity. [ABSTRACT FROM AUTHOR]

Background: Alterations in upper respiratory microbiomes have been implicated in shaping host health trajectories, including by limiting mucosal pathogen colonization. However, limited comparative studies of respiratory microbiome development and functioning across age groups have been performed. Herein, we perform shotgun metagenomic sequencing paired with pathogen inhibition assays to elucidate differences in nasal and oral microbiome composition and intermicrobial interactions across healthy 24-month-old infant (n = 229) and adult (n = 100) populations. Results: We find that beta diversity of nasal and oral microbiomes varies with age, with nasal microbiomes showing greater population-level variation compared to oral microbiomes. Infant microbiome alpha diversity was significantly lower across nasal samples and higher in oral samples, relative to adults. Accordingly, we demonstrate significant differences in genus- and species-level composition of microbiomes between sites and age groups. Antimicrobial resistome patterns likewise varied across body sites, with oral microbiomes showing higher resistance gene abundance compared to nasal microbiomes. Biosynthetic gene clusters encoding specialized metabolite production were found in higher abundance across infant oral microbiomes, relative to adults. Investigation of pathogen inhibition revealed greater inhibition of gram-negative and gram-positive bacteria by oral commensals, while nasal isolates had higher antifungal activity. Conclusions: In summary, we identify significant differences in the microbial communities inhabiting nasal and oral cavities of healthy infants relative to adults. These findings inform our understanding of the interactions impacting respiratory microbiome composition and functions related to colonization resistance, with important implications for host health across the lifespan. 5XcHcd9N21H4_6hqSTf5-o Video Abstract [ABSTRACT FROM AUTHOR]

Instrumented mouthguard systems (iMGs) are commonly used to study rigid body head kinematics across a variety of athletic environments. Previous work has found good fidelity for iMGs rigidly fixed to anthropomorphic test device (ATD) headforms when compared to reference systems, but few validation studies have focused on iMG performance in human cadaver heads. Here, we examine the performance of two boil-and-bite style iMGs in helmeted cadaver heads. Three unembalmed human cadaver heads were fitted with two instrumented boil-and-bite mouthguards [Prevent Biometrics and Diversified Technical Systems (DTS)] per manufacturer instructions. Reference sensors were rigidly fixed to each specimen. Specimens were fitted with a Riddell SpeedFlex American football helmet and impacted with a rigid impactor at three velocities and locations. All impact kinematics were compared at the head center of gravity. The Prevent iMG performed comparably to the reference system up to ~ 60 g in linear acceleration, but overall had poor correlation (CCC = 0.39). Prevent iMG angular velocity and BrIC generally well correlated with the reference, while underestimating HIC and overestimating HIC duration. The DTS iMG consistently overestimated the reference across all measures, with linear acceleration error ranging from 10 to 66%, and angular acceleration errors greater than 300%. Neither iMG demonstrated consistent agreement with the reference system. While iMG validation efforts have utilized ATD testing, this study highlights the need for cadaver testing and validation of devices intended for use in-vivo, particularly when considering realistic (non-idealized) sensor-skull coupling, when accounting for interactions with the mandible and when subject-specific anatomy may affect device performance. [ABSTRACT FROM AUTHOR]

Heatwaves in southeastern Australia have characteristic weather patterns that are well understood but are outnumbered by days with similar synoptic‐scale patterns that are not heatwaves. Accordingly, the aim of this study is to identify the key differences between heatwave and non‐heatwave days from 40 years of reanalysis data. A synoptic climatology of seven weather states was constructed by k$$ k $$‐means cluster analysis. Four of these states account for more than 80% of heatwave days across south‐and‐central eastern Australia. Moreover, the spatial maxima in the frequency of the heatwave days are distinct and geographically separated. Heatwave days have a stronger upper anticyclone or ridge that has propagated further equatorward in comparison with non‐heatwave days. The air upstream of the ridge is more humid on heatwave days, whereas downstream of the ridge the air is much drier. These dry anomalies are co‐located with midtropospheric subsidence and the moist anomalies with ascent, and their respective spatial distributions are consistent with regions of adiabatic warming and latent heating identified in recent studies of southeast Australian heatwaves. The corresponding vertical motion on non‐heatwave days is weaker and shifted further poleward. Southeast Queensland heatwave days exhibit increased baroclinicity over the Australian Subtropics and reduced rainfall over Queensland. Further south and west, heatwave days are associated with more amplified Rossby waves and increased rainfall over the Australian Tropics. Anticyclonic Rossby wave breaking is greatly enhanced on heatwave days south of 30°S. For every day in each of these four weather states, the 3‐day‐mean maximum temperature in the region of peak heatwave day frequency is positively correlated with 500 hPa geopotential height anomalies on the equatorward flank of the cluster‐mean upper ridge. These findings underline the importance of equatorward Rossby wave propagation in the dynamics of southeast Australian heatwaves. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the effect of artificially rearing Holstein Friesian bull calves with either forage- (FS) or concentrate-based starter diets on rumen fermentation and blood metabolite profiles to 4.5 mo, residual feed intake (RFI) at 10 mo, lifetime growth, and carcass traits and meat quality at slaughter in a pastoral grazing system. Holstein-Friesian bull calves were allocated to FS or PS diets (n = 20/group). The FS calves grew slower than PS calves following MR weaning up to 100 kg BW but tended to grow faster up to 18 wks while grazing pasture with no difference in BW observed thereafter. Rumen fermentation profiles differed at wk 7 and 12 but not thereafter. Residual feed intake (RFI), age and weight at slaughter and meat yield/quality were similar between groups. These results highlight that artificially reared Friesian bulls fed a FS compared to PS starter diet take slightly longer to reach 100 kg BW but are better prepared for weaning onto pasture, with no long-term differences in RFI, growth and beef production/quality. This study highlights the opportunity for beef producers to utilise a whole of life grain-free alternative feeding system to meet specific market requirements. [ABSTRACT FROM AUTHOR]

Introduction: The severity of Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is often dictated by a range of comorbidities. A considerable literature suggests iron deficiency and iron overload may contribute to increased infection, inflammation and disease severity, although direct causal relationships have been difficult to establish. Methods: Here we generate iron deficient and iron loaded C57BL/6 J mice by feeding standard low and high iron diets, with mice on a normal iron diet representing controls. All mice were infected with a primary SARS-CoV-2 omicron XBB isolate and lung inflammatory responses were analyzed by histology, immunohistochemistry and RNA-Seq. Results: Compared with controls, iron deficient mice showed no significant changes in lung viral loads or histopathology, whereas, iron loaded mice showed slightly, but significantly, reduced lung viral loads and histopathology. Transcriptional changes were modest, but illustrated widespread dysregulation of inflammation signatures for both iron deficient vs. controls, and iron loaded vs. controls. Some of these changes could be associated with detrimental outcomes, whereas others would be viewed as beneficial. Discussion: Diet-associated iron deficiency or overload thus induced modest modulations of inflammatory signatures, but no significant histopathologically detectable disease exacerbations. [ABSTRACT FROM AUTHOR]

The dynamical environment of the stratosphere, during the summer over North America, provides a natural integrator of the impact of convection in the lower stratosphere, as air can be confined for periods of a few days to more than a week. In situ data obtained during the NASA Dynamics and Chemistry of the Summer Stratosphere (DCOTSS) field campaign show increasing water vapor mixing ratios in background air as a function of time the air parcel spent within the North American Monsoon Anticyclone region. We find that water vapor added to the stratosphere by convection decreases with altitude and tends to drop below detectable limits by the 415 K isentrope in 2021 and the 430 K isentrope in 2022. Integrating between potential temperatures of 380 and 460 K we find that convection added between 20 and 32 Tg per summer to the stratosphere in 2021 and 2022. While the total amount is only 1%–4% of the amount ascending in the tropics across the tropical tropopause, small changes in the annual flux of water can have a significant effect on the radiation budget of the atmosphere. Locally, over North America we find that convection increased the water vapor mixing ratio at 380 K by as much as 40%. Tropopause‐penetrating convection is part of the yearly cycle of stratospheric water vapor and we suggest that it must be included in extratropical models to accurately predict future trends in stratospheric water vapor. Plain Language Summary: Water vapor in the stratosphere is important for regulating Earth's climate and also influences the amount of ozone in the stratosphere. Most air rises into the stratosphere through the tropical tropopause where the excess water freezes out leaving very dry air. But air and water can also be injected into the stratosphere via strong convective storm systems. During the summer months, strong storms over the Sierra Madre Occidental and the central United States are known to produce many overshoots that can be seen with radar and satellite. A recent NASA airborne campaign called Dynamics and Chemistry of the Summer Stratosphere (DCOTSS) aimed to study this region. The aircraft was equipped with 12 different sensors measuring gases, aerosols, and meteorological variables. We use these measurements to look at the cumulative effect these storms have on the background air in the stratosphere and specifically calculate the amount of water vapor added by convection as a function of altitude above the tropopause. We find that water added by storms over North America is 1%–4% of the total amount ascending in the tropics. Over North America convection may account for as much as a 40% increase in lower stratospheric water vapor. Key Points: Deep convection over North America lofts significant amounts of water to the lower stratosphereThe North American Monsoon Anticyclone (NAMA) provides a natural integrator of convective perturbations to the stratosphereConvective detrainment of water vapor and ice is quantified by looking at changes in background air as a function of time spent in the NAMA [ABSTRACT FROM AUTHOR]

It is suggested that in addition to seismicity deep fluid injection may cause surface uplift and subsidence in oil and gas‐producing regions. This study uses the Raton Basin as an example to investigate the hydromechanical processes of surface uplift and subsidence during wastewater injection. The Raton Basin, in southern central Colorado and northern central New Mexico, has experienced wastewater injection related to coalbed methane and gas production starting in 1994. In this study, we estimate the extent and magnitude of total vertical deformation in the Raton Basin from 1994 to 2020 and incremental deformation between the years 2017 to 2020. Results indicate a modeled uplift as much as 15 cm occurring between 1994 and 2020. Between 2017 and 2020, up to 3 cm of uplift occurred, largely near the northwestern injection wells. Most modeled uplift between 1994 and 2020 occurred near the southern wells, where the greatest cumulative volume of wastewater was injected. However, modeled subsidence occurred around the southern and eastern wells between 2017 and 2020, after the rate of injection decreased. Modeling indicates that while the magnitude of modeled uplift corresponds to cumulative injection volume and maximum rate in the long‐term, short‐term incremental deformation (uplift or subsidence) is controlled by changes in the rate of injection. The number of yearly earthquake events follows periods of rapid modeled uplifting throughout the Basin, suggesting that measurable surface deformation may be caused by the same injection‐induced pore pressure perturbations that initiate seismicity. [ABSTRACT FROM AUTHOR]

Emerging active regions are associated with convective flows on the spatial scale and lifetimes of supergranules. To understand how these flows are involved in the formation of active regions, we aim to identify where active regions emerge in the supergranulation flow pattern. We computed supergranulation scale flow maps at the surface for all active regions in the Solar Dynamics Observatory Helioseismic Emerging Active Region Survey. We classified each of the active regions into four bins based on the amplitude of their average surface flow divergence at emergence. We then averaged the flow divergence over the active regions in each bin as a function of time. We also considered a corresponding set of control regions. We found that, on average, the flow divergence increases during the day prior to emergence at a rate independent of the amount of flux that emerges. By subtracting the averaged flow divergence of the control regions, we found that active region emergence is associated with a remaining converging flow at 0.5–1 d prior to emergence. This remnant flow, |$\Delta \, \mathrm{div} \, \boldsymbol {v}_{\rm h} = (-4.9 \pm 1.7) \times 10^{-6}\,{\rm s}^{-1}$|⁠ , corresponds to a flow speed of 10–20 m s−1 (an order of magnitude less than supergranulation flows) out to a radius of about 10 Mm. We show that these observational results are qualitatively supported by simulations of a small bipole emerging through the near-surface convective layers of the Sun. The question remains whether these flows are driving the emergence, or are caused by the emergence. [ABSTRACT FROM AUTHOR]

Students' perceived belonging in academic spaces has emerged as a critical nexus of overall academic achievement, social-emotional outcomes (e.g., self-concept and self-efficacy), and engagement in K–12 schools. Furthermore, researchers have documented inverse relations of belonging and psychological distress, alienation, and isolation. The purpose of this study was to investigate differences in participants' levels of belonging in band ensembles and school outside of band ensembles. Participants of this quantitative study—suburban and rural high school band students in the Pacific Northwest region of the United States—responded to modified General Belongingness Scales and a Rosenberg Self-Esteem Scale to measure individuals' perceived levels of belonging both in their band ensembles and in their schools outside of band ensembles. The data indicated that secondary music students experienced greater levels of belonging in band ensembles than in the school environment outside of band ensembles. These findings highlight the potential for band classes/ensembles to foster belonging and support social-emotional well-being for high school students and have the potential to inform secondary education policy. [ABSTRACT FROM AUTHOR]

Hydration of the stratosphere by tropopause‐overshooting convection has received increasing interest due to the extreme concentrations of water vapor that can result and, ultimately, the climate warming potential such hydration provides. Previous work has recognized the importance of numerous dynamic and physical processes that control stratospheric water vapor delivery by convection. This study leverages recent comprehensive observations from the NASA Dynamics and Chemistry of the Summer Stratosphere (DCOTSS) field campaign to determine the frequency at which each process operates during real events. Specifically, a well‐established analysis technique known as tracer‐tracer correlation is applied to DCOTSS observations of ozone, water vapor, and potential temperature to identify the occurrence of known processes. It is found that approximately half of convectively‐driven stratospheric hydration samples show no indication of significant air mass transport and mixing, emphasizing the importance of ice sublimation to stratospheric water vapor delivery. Furthermore, the temperature of the upper troposphere and lower stratosphere environment and/or overshoot appears to be a commonly active constraint, since the approximate maximum possible water vapor concentration that can be reached in an air mass is limited to the saturation mixing ratio when ice is present. Finally, little evidence of relationships between dynamic and physical processes and their spatial distribution was found, implying that stratospheric water vapor delivery by convection is likely facilitated by a complex collection of processes in each overshooting event. Plain Language Summary: Thunderstorms are capable of transporting air and water up to the second layer of Earth's atmosphere, the stratosphere. Resulting irreversible modifications to greenhouse gases that regulate climate, such as water vapor and ozone, are important to quantify and poorly understood. This study uses recently‐obtained aircraft observations to improve understanding of irreversible transport in thunderstorms and the environmental and storm factors that control it. By examining how multiple trace gases and other quantities co‐vary, it is found that half of observed stratospheric changes by thunderstorms only exhibit increases in water vapor, which is argued to be driven by transported ice. It is also found that the environmental temperature is an important constraint in any storm because it limits the amount of stratospheric water vapor change that can occur. Key Points: Recent airborne observations reveal key dynamic and physical processes controlling the stratospheric delivery of water vapor by convectionIn situ observations suggest that water vapor is delivered routinely via both air transport and ice sublimationTemperature is an important constraint for water vapor delivery in any stratospheric environment [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the 1 repetition maximum (1RM) of the jump shrug (JS) using the barbell acceleration characteristics of repetitions performed with relative percentages of the hang power clean (HPC). Fifteen resistance-trained men (age = 25.5 ± 4.5 years, body mass = 88.5 ± 15.7 kg, height = 176.1 ± 8.5 cm, relative 1RM HPC = 1.3 ± 0.2 kg⋅kg-1) completed 2 testing sessions that included performing a 1RM HPC and JS repetitions with 20, 40, 60, 80, and 100% of their 1RM HPC. A linear position transducer was used to determine concentric duration and the percentage of the propulsive phase (P%) where barbell acceleration was greater than gravitational acceleration (i.e., a>-9.81 m⋅s-2). Two 1 way repeated measures ANOVA were used to compare each variable across loads, whereas Hedge's g effect sizes were used to examine the magnitude of the differences. Concentric duration ranged from 449.7 to 469.8 milliseconds and did not vary significantly between loads (p = 0.253; g = 0.20-0.39). The P% was 57.4 ± 7.2%, 64.8 ± 5.9%, 73.2 ± 4.3%, 78.7 ± 4.0%, and 80.3 ± 3.5% when using 20,40,60, 80, and 100% 1RM HPC, respectively. P% produced during the 80 and 100% 1RM loads were significantly greater than those at 20, 40, and 60% 1RM (p < 0.01, g = 1.30-3.90). In addition, P% was significantly greater during 60% 1RM compared with both 20 and 40% 1RM (p < 0.01, g = 1.58-2.58) and 40% was greater than 20% 1RM (p = 0.003, g = 1.09). A braking phase was present during each load and, thus, a 1RM JS load was not established. Heavier loads may be needed to achieve a 100% propulsive phase when using this method. [ABSTRACT FROM AUTHOR]

Higher self‐reported rumination, a common form of trait perseverative cognition, is linked with lower resting heart rate variability (HRV), which indicates poorer cardiac function and greater disease risk. A meta‐analysis and systematic review indicated that in samples with fewer European Americans, the association of rumination with both heart rate and blood pressure was stronger. Thus, trait rumination may be more strongly associated with resting HRV among ethnically minoritized populations. The current study investigated whether differences in the association of self‐reported rumination with resting HRV varied by ethnicity in a sample (N = 513; Mage = 19.41; 226 Women) of self‐identified African Americans (n = 110), Asian Americans (n = 84), and European Americans (n = 319). Participants completed a five‐minute baseline period to assess resting HRV, followed by the Ruminative Responses Scale, which contains three facets of rumination including brooding, depressive, and reflective rumination. On average, Asian Americans reported higher levels of rumination relative to European Americans. African Americans had higher resting HRV than Asian Americans. Adjusting for covariates, higher self‐reported rumination was significantly associated with lower resting HRV in both African and Asian Americans, but not significantly so in European Americans. This finding was consistent for brooding and reflective, but not depressive rumination. Overall, this study lends insight into a psychological mechanism—rumination—that may impact health disparities among ethnically minoritized individuals, contributing to an understanding of how stress gets under the skin among such minoritized populations. [ABSTRACT FROM AUTHOR]

Limonium bicolor is a perennial salt-secretion halophyte with salt glands growing in the coastal areas around Bohai Sea of China. The aim of this study was to investigate the growth, physiological and biochemical responses of L. bicolor when subjected to different concentrations of NaCl by measuring the following: growth parameters; ion, proline, soluble sugar and soluble protein contents; and the level of lipid peroxidation. Photosynthetic pigment concentrations, chlorophyll fluorescence parameters, and antioxidant enzyme activities were also determined. Shoot growth was inhibited by increasing salinity, while root growth was promoted under salt stress of 90–360 mM NaCl. Compared to the Na+ and Cl− accumulations of the control, those in both leaves and roots were markedly promoted by increasing salinity, while no significant change in K+ concentration occurred. Proline, soluble sugar and soluble protein contents increased significantly with increasing salinity. The POD and APX antioxidant system was effective in scavenging ROS generated by salt-induced oxidative stress, as indicated by consistent MDA levels at 90–270 mM NaCl. Chlorophyll contents, Fv/Fm, Yield and qP decreased significantly, while qN increased markedly with salt stress duration and increasing salt concentration. Overall, these results suggest that the salt tolerance mechanism of L. bicolor is regulated by ion homeostasis, osmotic adjustment, the antioxidant enzyme system and photosynthesis. [ABSTRACT FROM AUTHOR]

Suchomel, TJ, Techmanski, BS, Kissick, CR, and Comfort, P. Can the velocity of a 1RM hang power clean be used to estimate a 1RM hang high pull? J Strength Cond Res 38(7): 1321-1325, 2024-The purpose of this study was to estimate the 1-repetition maximum hang high pull (1RM HHP) using the peak barbell velocity of a 1RM hang power clean (HPC). Fifteen resistance-trained men (age = 25.5 ± 4.5 years, body mass = 88.3 ± 15.4 kg, height = 176.1±8.5 cm, relative 1RM HPC = 1.3±0.2 kg-kg-1) with previous HPC experience participated in 2 testing sessions that included performing a 1RM HPC and HHP repetitions with 20, 40, 60, and 80% of their 1RM HPC. Peak barbell velocity was measured using a linear position transducer during the 1RM HPC and HHP repetitions performed at each load. The peak barbell velocity achieved during the 1RM HPC was determined as the criterion value for a 1RM performance. Subject-specific linear regression analyses were completed using slope-intercept equations created from the peak velocity of the 1RM HPC and the peak barbell velocities produced at each load during the HHP repetitions. The peak barbell velocity during the 1RM HPC was 1.74 ± 0.30 m-s-¹. The average load-velocity profile showed that the estimated 1RM HHP of the subjects was 98.0 ± 19.3% of the 1RM HPC. Although a 1RM HHP value may be estimated using the peak barbell velocity during the HPC, strength and conditioning practitioners should avoid this method because of the considerable variation within the measurement. Additional research examining different methods of load prescription for weightlifting pulling derivatives is needed. [ABSTRACT FROM AUTHOR]

Tropopause-overshooting convection in the midlatitudes provides a rapid transport pathway for air from the lower troposphere to reach the upper troposphere and lower stratosphere (UTLS) and can result in the formation of above-anvil cirrus plumes (AACPs) that significantly hydrate the stratosphere. Such UTLS composition changes alter the radiation budget and impact climate. Novel in situ observations from the NASA Dynamics and Chemistry of the Summer Stratosphere (DCOTSS) field campaign are used in this study to examine UTLS impacts from AACP-generating overshooting convection. Namely, a research flight on 31 May 2022 sampled active convection over the state of Oklahoma for more than 3 h with the NASA ER-2 high-altitude research aircraft. An AACP was bisected during this flight, providing the first such extensive in situ sampling of this phenomenon. The convective observations reveal pronounced changes in air mass composition and stratospheric hydration up to altitudes of 2.3 km above the tropopause and concentrations more than double background levels. Unique dynamic and trace gas signatures were found within the AACP, including enhanced vertical mixing near the AACP edge and a positive correlation between water vapor and ozone. Moreover, the water vapor enhancement within the AACP was found to be limited to the saturation mixing ratio of the low temperature overshoot and AACP air. Comparison with all remaining DCOTSS flights demonstrates that the 31 May 2022 flight had some of the largest tropospheric tracer and water vapor perturbations in the stratosphere and within the AACP. [ABSTRACT FROM AUTHOR]

We evaluated use of maribavir (MBV) for treatment of 15 episodes of refractory/resistant cytomegalovirus infection in 13 solid organ transplant recipients. Treatment failure due to treatment-emergent MBV resistance or early virological recurrence after MBV discontinuation occurred in 7 (47%) episodes. Sustained viral clearance was achieved in 6 (40%) episodes. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms that drive HIV expression and latency is a key goal for achieving an HIV cure. Here we investigate the role of the SETD2 histone methyltransferase, which deposits H3K36 trimethylation (H3K36me3), in HIV infection. We show that prevention of H3K36me3 by a potent and selective inhibitor of SETD2 (EPZ-719) leads to reduced post-integration viral gene expression and accelerated emergence of latently infected cells. CRISPR/Cas9-mediated knockout of SETD2 in primary CD4 T cells confirmed the role of SETD2 in HIV expression. Transcriptomic profiling of EPZ-719-exposed HIV-infected cells identified numerous pathways impacted by EPZ-719. Notably, depletion of H3K36me3 prior to infection did not prevent HIV integration but resulted in a shift of integration sites from highly transcribed genes to quiescent chromatin regions and to polycomb repressed regions. We also observed that SETD2 inhibition did not apparently affect HIV RNA levels, indicating a post-transcriptional mechanism affecting HIV expression. Viral RNA splicing was modestly reduced in the presence of EPZ-719. Intriguingly, EPZ-719 exposure enhanced responsiveness of latent HIV to the HDAC inhibitor vorinostat, suggesting that H3K36me3 can contribute to a repressive chromatin state at the HIV locus. These results identify SETD2 and H3K36me3 as novel regulators of HIV integration, expression and latency. Author summary: HIV persists in people during therapy by entering a state of latency, where viral genes are not expressed. This reservoir of latently infected cells is the key barrier to curing HIV. In this manuscript, we examine the role of the cellular enzyme SETD2 in HIV infection and expression. SETD2 generates H3K36me3 modifications on histone proteins that associate with cellular DNA. We find that H3K36me3 modifications are abundantly present on the integrated HIV genome during infection. We observed that inhibiting SETD2 with the compound EPZ-719 leads to HIV integrating into different regions of the human genome and reduces HIV expression. Interestingly, this also increased the sensitivity of latent HIV to reactivation by histone deacetylase inhibitors. EPZ-719 did not apparently impact the transcription of HIV RNA, but affected splicing of the viral RNA into coding transcripts. Overall, these results show that SETD2 influences HIV integration and expression. SETD2 may be a useful new target for reactivating HIV gene expression in people with HIV. [ABSTRACT FROM AUTHOR]

Purpose: Antimicrobial misuse contributes to antimicrobial resistance in thoracic transplant (TTx) and mechanical circulatory support (MCS) recipients. This study uses a modified Delphi method to define the expected appropriate antimicrobial prescribing for the common clinical scenarios encountered in TTx and MCS recipients. Methods: An online questionnaire on managing 10 common infectious disease syndromes was submitted to a multidisciplinary Delphi panel of 25 experts from various disciplines. Consensus was predefined as 80% agreement for each question. Questions where consensus was not achieved were discussed during live virtual live sessions adapted by an independent process expert. Results: An online survey of 62 questions related to 10 infectious disease syndromes was submitted to the Delphi panel. In the first round of the online questionnaire, consensus on antimicrobial management was reached by 6.5% (4/62). In Round 2 online live discussion, the remaining 58 questions were discussed among the Delphi Panel members using a virtual meeting platform. Consensus was reached among 62% (36/58) of questions. Agreement was not reached regarding the antimicrobial management of the following six clinical syndromes: (1) Burkholderia cepacia pneumonia (duration of therapy); (2) Mycobacterium abscessus (intra‐operative antimicrobials); (3) invasive aspergillosis (treatment of culture‐negative but positive BAL galactomannan) (duration of therapy); (4) respiratory syncytial virus (duration of antiviral therapy); (5) left ventricular assist device deep infection (initial empirical antimicrobial coverage) and (6) CMV (duration of secondary prophylaxis). Conclusion: This Delphi panel developed consensus‐based recommendations for 10 infectious clinical syndromes seen in TTx and MCS recipients. [ABSTRACT FROM AUTHOR]

Low precision training can significantly reduce the computational overhead of training deep neural networks (DNNs). Though many such techniques exist, cyclic precision training (CPT), which dynamically adjusts precision throughout training according to a cyclic schedule, achieves particularly impressive improvements in training efficiency, while actually improving DNN performance. Existing CPT implementations take common learning rate schedules (e.g., cyclical cosine schedules) and use them for low precision training without adequate comparisons to alternative scheduling options. We define a diverse suite of CPT schedules and analyze their performance across a variety of DNN training regimes, some of which are unexplored in the low precision training literature (e.g., node classification with graph neural networks). From these experiments, we discover alternative CPT schedules that offer further improvements in training efficiency and model performance, as well as derive a set of best practices for choosing CPT schedules. Going further, we find that a correlation exists between model performance and training cost, and that changing the underlying CPT schedule can control the tradeoff between these two variables. To explain the direct correlation between model performance and training cost, we draw a connection between quantized training and critical learning periods, suggesting that aggressive quantization is a form of learning impairment that can permanently damage model performance. [ABSTRACT FROM AUTHOR]

Introduction: Global microplastic (MP) pollution is now well recognized, with humans and animals consuming and inhaling MPs on a daily basis, with a growing body of concern surrounding the potential impacts on human health. Methods: Using a mouse model of mild COVID-19, we describe herein the effects of azide-free 1 mm polystyrene MP beads, co-delivered into lungs with a SARS-CoV-2 omicron BA.5 inoculum. The effect of MPs on the host response to SARS-CoV-2 infection was analysed using histopathology and RNA-Seq at 2 and 6 days post-infection (dpi). Results: Although infection reduced clearance of MPs from the lung, virus titres and viral RNA levels were not significantly affected by MPs, and overt MPassociated clinical or histopathological changes were not observed. However, RNA-Seq of infected lungs revealed that MP exposure suppressed innate immune responses at 2 dpi and increased pro-inflammatory signatures at 6 dpi. The cytokine profile at 6 dpi showed a significant correlation with the 'cytokine release syndrome' signature observed in some COVID-19 patients. Discussion: The findings are consistent with the recent finding that MPs can inhibit phagocytosis of apoptotic cells via binding of Tim4. They also add to a growing body of literature suggesting that MPs can dysregulate inflammatory processes in specific disease settings. [ABSTRACT FROM AUTHOR]

Introduction: Global microplastic (MP) pollution is now well recognized, with humans and animals consuming and inhaling MPs on a daily basis, with a growing body of concern surrounding the potential impacts on human health. Methods: Using a mouse model of mild COVID-19, we describe herein the effects of azide-free 1 μm polystyrene MP beads, co-delivered into lungs with a SARS-CoV-2 omicron BA.5 inoculum. The effect of MPs on the host response to SARS-CoV-2 infection was analysed using histopathology and RNA-Seq at 2 and 6 days post-infection (dpi). Results: Although infection reduced clearance of MPs from the lung, virus titres and viral RNA levels were not significantly affected by MPs, and overt MP-associated clinical or histopathological changes were not observed. However, RNA-Seq of infected lungs revealed that MP exposure suppressed innate immune responses at 2 dpi and increased pro-inflammatory signatures at 6 dpi. The cytokine profile at 6 dpi showed a significant correlation with the 'cytokine release syndrome' signature observed in some COVID-19 patients. Discussion: The findings are consistent with the recent finding that MPs can inhibit phagocytosis of apoptotic cells via binding of Tim4. They also add to a growing body of literature suggesting that MPs can dysregulate inflammatory processes in specific disease settings. [ABSTRACT FROM AUTHOR]

Observed spectral profiles of emission lines from the corona are found to have widths exceeding the thermal line width. To investigate the physical mechanism, we run a 3D magnetohydrodynamics model of a single, straightened loop in which we partially resolve turbulent motions that form in response to the driving by self-consistently evolving magneto-convection in the photosphere. The convective motions shear and twist the magnetic field lines, leading to heating. From the model, we synthesize spectral profiles of emission lines forming at temperatures around and above 1 MK. The coronal heating process generates a range of velocity amplitudes and directions structured on a scale much smaller than the resolving power of current instruments, leading to a broadening of the spectral lines. Our model includes the mass exchange between corona and chromosphere, thus we also capture flows parallel to the loop axis. We find that the spectral lines show a non-thermal line broadening roughly consistent with observations for a viewing angle perpendicular to the axis. The broadening through field-parallel flows is comparable, although slightly smaller. The line broadening is independent of the instrument resolution for a perpendicular line of sight (LOS). We can connect the non-thermal line broadening to heating events and flows. While small-scale velocities along the LOS are mainly responsible for the broadening observed perpendicular to the loop, chromospheric evaporation is important for the line broadening observed along the loop. The model reproduces observed values for non-thermal line widths. In the model, these result from continuous driving by magnetoconvection, without imposing driving motions or starting from an already braided field. [ABSTRACT FROM AUTHOR]

Background: Human genetic contribution to HIV progression remains inadequately explained. The type 1 interferon (IFN) pathway is important for host control of HIV and variation in type 1 IFN genes may contribute to disease progression. This study assessed the impact of variations at the gene and pathway level of type 1 IFN on HIV-1 viral load (VL). Methods: Two cohorts of antiretroviral (ART) naïve participants living with HIV (PLWH) with either early (START) or advanced infection (FIRST) were analysed separately. Type 1 IFN genes (n = 17) and receptor subunits (IFNAR1, IFNAR2) were examined for both cumulated type 1 IFN pathway analysis and individual gene analysis. SKAT-O was applied to detect associations between the genotype and HIV-1 study entry viral load (log10 transformed) as a proxy for set point VL; P-values were corrected using Bonferroni (P < 0.0025). Results: The analyses among those with early infection included 2429 individuals from five continents. The median study entry HIV VL was 14,623 (IQR 3460–45100) copies/mL. Across 673 SNPs within 19 type 1 IFN genes, no significant association with study entry VL was detected. Conversely, examining individual genes in START showed a borderline significant association between IFNW1, and study entry VL (P = 0.0025). This significance remained after separate adjustments for age, CD4+ T-cell count, CD4+/CD8+ T-cell ratio and recent infection. When controlling for population structure using linear mixed effects models (LME), in addition to principal components used in the main model, this was no longer significant (p = 0.0244). In subgroup analyses stratified by geographical region, the association between IFNW1 and study entry VL was only observed among African participants, although, the association was not significant when controlling for population structure using LME. Of the 17 SNPs within the IFNW1 region, only rs79876898 (A > G) was associated with study entry VL (p = 0.0020, beta = 0.32; G associated with higher study entry VL than A) in single SNP association analyses. The findings were not reproduced in FIRST participants. Conclusion: Across 19 type 1 IFN genes, only IFNW1 was associated with HIV-1 study entry VL in a cohort of ART-naïve individuals in early stages of their infection, however, this was no longer significant in sensitivity analyses that controlled for population structures using LME. [ABSTRACT FROM AUTHOR]

We determine the conjugacy classes of the Poincaré group ISO+(n, 1) and apply this to classify the stationary trajectories of Minkowski spacetimes in terms of timelike Killing vectors. Stationary trajectories are the orbits of timelike Killing vectors and, equivalently, the solutions to Frenet–Serret equations with constant curvature coefficients. We extend the 3 + 1 Minkowski spacetime Frenet–Serret equations due to Letaw to Minkowski spacetimes of arbitrary dimension. We present the explicit families of stationary trajectories in 4 + 1 Minkowski spacetime. [ABSTRACT FROM AUTHOR]

A unique acoustic call type was identified and attributed to Bryde's whales in the central North Pacific in 2015, but little is known about the distribution, calling behavior, or swimming behavior of Bryde's whales in the region. Acoustic detections attributed to Bryde's whales were used to localize and track individual whales on the U.S. Pacific Missile Range Facility (PMRF) in Kaua'i, Hawai'i. This study included 150 acoustically derived tracks from recordings spanning the years 2011-2022 with recording effort in nearly every month. Bryde's whale movement was examined relative to calendar year, day of year, hour of day, wind speed, and acoustic calling rate. Hidden Markov models were used to identify two kinematic states (slower, less directional movement and faster, more directional movement). The findings indicate that Bryde's whales were more likely to travel in a faster and more directional state during the daytime than at night and between May and August when compared to other times of year. The along-track acoustic cue rate was examined for 118 tracks, and the findings indicate a possible lengthening of the median inter-call interval over the duration of the study period. These results are an important first step in understanding more about behavior in Bryde's whales, a relatively understudied species. [ABSTRACT FROM AUTHOR]

Myeloid derived suppressor cells (MDSCs) are key regulators of immune responses and correlate with poor outcomes in hematologic malignancies. Here, we identify that MDSC mitochondrial fitness controls the efficacy of doxorubicin chemotherapy in a preclinical lymphoma model. Mechanistically, we show that triggering STAT3 signaling via β2-adrenergic receptor (β2-AR) activation leads to improved MDSC function through metabolic reprograming, marked by sustained mitochondrial respiration and higher ATP generation which reduces AMPK signaling, altering energy metabolism. Furthermore, induced STAT3 signaling in MDSCs enhances glutamine consumption via the TCA cycle. Metabolized glutamine generates itaconate which downregulates mitochondrial reactive oxygen species via regulation of Nrf2 and the oxidative stress response, enhancing MDSC survival. Using β2-AR blockade, we target the STAT3 pathway and ATP and itaconate metabolism, disrupting ATP generation by the electron transport chain and decreasing itaconate generation causing diminished MDSC mitochondrial fitness. This disruption increases the response to doxorubicin and could be tested clinically. [ABSTRACT FROM AUTHOR]

This post hoc analysis of the randomized, double-blind, placebo-controlled trial ACTT-2 (Adaptive COVID-19 Treatment Trial-2) sought to determine whether any patient characteristics are associated with treatment benefit from the immunomodulator baricitinib among hospitalized patients with COVID-19 who fall into the "high-risk" quartile. Visual Abstract. A Risk Profile Using Simple Hematologic Parameters to Assess Benefits From Baricitinib in Patients Hospitalized With COVID-19: A Post Hoc Analysis of the Adaptive COVID-19 Treatment Trial-2 This post hoc analysis of the randomized, double-blind, placebo-controlled trial ACTT-2 (Adaptive COVID-19 Treatment Trial-2) sought to determine whether any patient characteristics are associated with treatment benefit from the immunomodulator baricitinib among hospitalized patients with COVID-19 who fall into the "high-risk" quartile. Background: The ACTT risk profile, which was developed from ACTT-1 (Adaptive COVID-19 Treatment Trial-1), demonstrated that hospitalized patients with COVID-19 in the high-risk quartile (characterized by low absolute lymphocyte count [ALC], high absolute neutrophil count [ANC], and low platelet count at baseline) benefited most from treatment with the antiviral remdesivir. It is unknown which patient characteristics are associated with benefit from treatment with the immunomodulator baricitinib. Objective: To apply the ACTT risk profile to the ACTT-2 cohort to investigate potential baricitinib-related treatment effects by risk quartile. Design: Post hoc analysis of ACTT-2, a randomized, double-blind, placebo-controlled trial. (ClinicalTrials.gov: NCT04401579) Setting: Sixty-seven trial sites in 8 countries. Participants: Adults hospitalized with COVID-19 (n = 999; 85% U.S. participants). Intervention: Baricitinib+remdesivir versus placebo+remdesivir. Measurements: Mortality, progression to invasive mechanical ventilation (IMV) or death, and recovery, all within 28 days; ALC, ANC, and platelet count trajectories. Results: In the high-risk quartile, baricitinib+remdesivir was associated with reduced risk for death (hazard ratio [HR], 0.38 [95% CI, 0.16 to 0.86]; P = 0.020), decreased progression to IMV or death (HR, 0.57 [CI, 0.35 to 0.93]; P = 0.024), and improved recovery rate (HR, 1.53 [CI, 1.16 to 2.02]; P = 0.002) compared with placebo+remdesivir. After 5 days, participants receiving baricitinib+remdesivir had significantly larger increases in ALC and significantly larger decreases in ANC compared with control participants, with the largest effects observed in the high-risk quartile. Limitation: Secondary analysis of data collected before circulation of current SARS-CoV-2 variants. Conclusion: The ACTT risk profile identifies a subgroup of hospitalized patients who benefit most from baricitinib treatment and captures a patient phenotype of treatment response to an immunomodulator and an antiviral. Changes in ALC and ANC trajectory suggest a mechanism whereby an immunomodulator limits severe COVID-19. Primary Funding Source: National Institute of Allergy and Infectious Diseases. [ABSTRACT FROM AUTHOR]

Motor vehicle accidents are the leading cause of death for young adults 18–29 years old worldwide, resulting in nearly 1 million years of life lost annually in the United States. Despite improvements in vehicle safety technologies, young women are at higher risk of dying in car crashes compared with men in matched scenarios. Vehicle crash testing primarily revolves around test dummies representative of the 50th percentile adult male, potentially resulting in these differences in fatality risk for female occupants compared to males. Vehicle occupants involved in fatal car crashes were matched using seating location, vehicle type, airbag deployment, seatbelt usage, and age. The relative risk for fatality (R) between males and females was calculated using a Double Pair Comparison. Young women (20s-40s) are at approximately 20% higher risk of dying in car crashes compared with men of the same age in matched scenarios. In passenger cars, 25-year-old female occupants in passenger car crashes from 1975–2020 exhibit R = 1.201 (95% CI 1.160–1.250) compared to 25-year-old males, and R-1.117 (95% CI 1.040–1.207) for passenger car crashes from 2010–2020. This trend persists across vehicle type, airbag deployment, seatbelt use, and number of vehicles involved in a crash. Known sex-based differences do not explain this large risk differential, suggesting a need for expanded test methodologies and research strategies to address as-yet unexplored sex differences in crash fatalities. These differences should be further investigated to ensure equitable crash protection. [ABSTRACT FROM AUTHOR]

Since salmon lice have developed resistance to pesticides, non-medicinal delousing treatments have become increasingly used to remove the parasite from fish on salmon farms in Norwegian waters. These novel techniques are an important means of controlling epidemics of lice at farms for maintaining the health of farmed fish and for preventing the spread of lice to wild salmonid populations. However, some treatments are associated with higher mortality rates and negative welfare impacts on the host fish. Furthermore, it is unclear how effective each treatment is in removing lice compared to alternatives. Here, in a controlled laboratory environment, we tested the efficacy of mechanical, warm water (28 °C and 34 °C), and freshwater treatments alone and in combination, and examined their welfare impact on host fish. Regardless of treatment group or control, the handling of fish through the experiment led to a reduction in lice load and decline in fish welfare. Among the treatments examined, the freshwater bath alone and in combination with other treatments had the greatest delousing efficacy. The 34 °C warm water baths also significantly reduced lice loads but led to worse welfare outcomes with fish having a higher prevalence of injuries and reduced growth and condition factor. Delousing treatments were however not associated with long-term effects on neuroendocrine parameters or stress coping ability, suggesting that immediate welfare impacts from these procedures are generally reversible. It was also found that sedating fish prior to treatment was shown to mitigate the welfare impact. These findings are useful for the needed optimization of delousing strategies for greater delousing efficacy and reduced welfare impact on fish. [ABSTRACT FROM AUTHOR]

Sleep during the midday, commonly referred to as siesta, is a common trait of animals that mainly sleep during the night. Work using Drosophila led to the identification of the daywake (dyw) gene, found to have anti‐siesta activity. Herein, we show that the DYW protein undergoes signal peptide‐dependent secretion, is present in the circulatory system, and accumulates in multiple organs, but, surprisingly, it is not detected in the brain where wake–sleep centers are located. The abundance of DYW in adult flies is regulated by age, sex, temperature, and the splicing efficiency of a nearby thermosensitive intron. We suggest that DYW regulates daytime wake–sleep balance in an indirect, extracerebral manner, via a multi‐organ network that interfaces with the circulatory system. [ABSTRACT FROM AUTHOR]

Tropopause-overshooting convection in the midlatitudes provides a rapid transport pathway for air from the lower troposphere to reach the upper troposphere and lower stratosphere (UTLS), and can result in the formation of above-anvil cirrus plumes (AACPs) that significantly hydrate the stratosphere. Such UTLS composition changes alter the radiation budget and impact climate. Novel in situ observations from the NASA Dynamics and Chemistry of the Summer Stratosphere (DCOTSS) field campaign are used in this study to examine UTLS impacts from AACP-generating overshooting convection. Namely, a research flight on 31 May 2022 sampled active convection over the state of Oklahoma for more than three hours with the NASA ER-2 high-altitude research aircraft. An AACP was bisected during this flight, providing the first such extensive in situ sampling of this phenomenon. The convective observations reveal pronounced changes in air mass composition and stratospheric hydration up to altitudes of 2.3 km above the tropopause and concentrations more than double background levels. Unique dynamic and trace gas signatures were found within the AACP, including enhanced vertical mixing near the AACP edge and a positive correlation between water vapor and ozone. Moreover, the water vapor enhancement within the AACP was found to be limited to the saturation mixing ratio of the low temperature overshoot and AACP air. Comparison with all remaining DCOTSS flights demonstrates that the 31 May 2022 flight had some of the largest tropospheric tracer and water vapor perturbations in the stratosphere and within the AACP. [ABSTRACT FROM AUTHOR]

Tropopause-overshooting convection in the midlatitudes provides a rapid transport pathway for air from the lower troposphere to reach the upper troposphere and lower stratosphere (UTLS), and can result in the formation of above-anvil cirrus plumes (AACPs) that significantly hydrate the stratosphere. Such UTLS composition changes alter the radiation budget and impact climate. Novel in situ observations from the NASA Dynamics and Chemistry of the Summer Stratosphere (DCOTSS) field campaign are used in this study to examine UTLS impacts from AACP-generating overshooting convection. Namely, a research flight on 31 May 2022 sampled active convection over the state of Oklahoma for more than three hours with the NASA ER-2 high-altitude research aircraft. An AACP was bisected during this flight, providing the first such extensive in situ sampling of this phenomenon. The convective observations reveal pronounced changes in air mass composition and stratospheric hydration up to altitudes of 2.3 km above the tropopause and concentrations more than double background levels. Unique dynamic and trace gas signatures were found within the AACP, including enhanced vertical mixing near the AACP edge and a positive correlation between water vapor and ozone. Moreover, the water vapor enhancement within the AACP was found to be limited to the saturation mixing ratio of the low temperature overshoot and AACP air. Comparison with all remaining DCOTSS flights demonstrates that the 31 May 2022 flight had some of the largest tropospheric tracer and water vapor perturbations in the stratosphere and within the AACP. [ABSTRACT FROM AUTHOR]

The reduced pathogenicity of the omicron BA.1 sub-lineage compared to earlier variants is well described, although whether such attenuation is retained for later variants like BA.5 and XBB remains controversial. We show that BA.5 and XBB isolates were significantly more pathogenic in K18-hACE2 mice than a BA.1 isolate, showing increased neurotropic potential, resulting in fulminant brain infection and mortality, similar to that seen for original ancestral isolates. BA.5 also infected human cortical brain organoids to a greater extent than the BA.1 and original ancestral isolates. In the brains of mice, neurons were the main target of infection, and in human organoids neuronal progenitor cells and immature neurons were infected. The results herein suggest that evolving omicron variants may have increasing neurotropic potential. [ABSTRACT FROM AUTHOR]

Donor‐derived infections in solid organ transplantation can be prevented by risk stratification of donors based on available information, and inquiries surrounding possible or diagnosed infection are common questions posed to transplant infectious disease subspecialists. This article outlines the five key steps in addressing a donor call from a transplant team in a systematic approach, focusing on donor and recipient‐specific factors, transmissibility and treatment of possible infections, and the likelihood of a patient's future organ offers and mortality remaining on the waitlist. These principles are then applied to five donor call cases, in which we review the key takeaway points and supporting literature. These cases can be used as a resource for teaching with trainees. [ABSTRACT FROM AUTHOR]