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Global upper tropospheric kinetic energy (KE) spectra in several global atmospheric circulation datasets are examined. The datasets considered include the ERA-Interim, JRA-55, and ERA5 reanalyses and two versions of NOAA-GFS analyses at horizontal resolutions ranging from 0.7° to 0.12°. The mesoscale portions of the spectra are found to be highly inconsistent. This is shown to be mainly due to inconsistencies in the scale-dependent numerical damping and in the large contributions to the global mesoscale KE from the KE in convective regions and near orography. The spectra also generally have a steeper mesoscale slope than the -5/3 slope of the observational Nastrom-Gage spectrum pursued at many modeling centers. The sensitivity of the slope in global models to 1) stochastically perturbing diabatic tendencies and 2) decreasing the horizontal hyper-viscosity coefficient is explored in large ensembles of 10-day forecasts made with the NCEP-GFS (0.7° grid) model. Both changes lead to larger mesoscale KE and a flatter spectral slope. The effect is stronger in the modified hyper-viscosity experiment. These results show that (a) despite assimilating vastly more observations than used in the original Nastrom-Gage studies, current high-resolution global analyses still do not converge to a single “true” global mesoscale KE spectrum, and (b) model KE spectra can be made flatter not just by increasing model resolution but also by perturbing model physics and decreasing horizontal diffusion. Such sensitivities and lack of consensus on the spectral slope also raise the possibility that the true global mesoscale spectral slope may not be a precisely -5/3 slope.

It is well known that randomly perturbing an atmospheric model’s diabatic tendencies can increase its probabilistic forecast skill, mainly by increasing the spread of ensemble forecasts and making it more consistent with the errors of ensemble-mean forecasts. Less obvious and less well established is that such perturbations can also reduce the errors of the ensemble-mean forecasts and improve the model’s mean climate, variability, and sensitivity to forcing. A clear reduction in ensemble-mean forecast errors is demonstrated here in large ensembles of 15-day forecasts made with NOAA’s Global Forecast System model. The nearly ubiquitous reduction around the globe, obtained throughout the forecast range, is interpreted as arising in effect from a modification of the model’s deterministic evolution operator by a stochastic noise-induced drift. The effect is general in systems with state-dependent noise, and occurs even if the noise is not white. In the atmospheric context considered here, the effect is suggested to arise largely from noise-induced reductions of mechanical and thermal damping by chaotic boundary layer and cloud-radiative processes, which also tend to increase model sensitivity to forcing. The results presented here are consistent with many previous studies performed with models ranging from simple stochastically forced models to comprehensive global weather and climate models. They suggest that the diabatic interactions in most current global atmospheric models may not be sufficiently chaotic and this deficiency could be partly remedied by specifying additional stochastic terms. Using some empirical guidance in such specifications may be unavoidable, given the generally intractable complexity of the diabatic interactions.

Peritonitis is a major cause of morbidity and technique failure in patients receiving peritoneal dialysis. Complicated peritonitis that manifests as multiple or unresolving episodes is classified as refractory, recurrent, relapsing, or repeat peritonitis, and often possesses higher risk of technique failure and mortality as well as lower complete cure rates than primary or uncomplicated episodes. While these peritonitis subtypes affect a considerable portion of PD patients, details regarding their epidemiology, pathogenesis, diagnosis, clinical sequelae, and management have not yet been fully elucidated. Improved clinical awareness and understanding of complicated peritonitis subtypes is crucial to ensure optimal management for these patients; thus, we consolidate and report the pertinent findings of recent literature on these four entities.

In type-II Weyl semimetals (WSMs), the tilting of the Weyl cones leads to the coexistence of electron and hole pockets that touch at the Weyl nodes. These electrons and holes experience the Berry curvature generated by the Weyl nodes, leading to an anomalous Hall effect that is highly sensitive to the Fermi level position. Here we have identified field-induced ferromagnetic MnBi 2-x Sb x Te 4 as an ideal type-II WSM with a single pair of Weyl nodes. By employing a combination of quantum oscillations and high-field Hall measurements, we have resolved the evolution of Fermi-surface sections as the Fermi level is tuned across the charge neutrality point, precisely matching the band structure of an ideal type-II WSM. Furthermore, the anomalous Hall conductivity exhibits a heartbeat-like behavior as the Fermi level is tuned across the Weyl nodes, a feature of type-II WSMs that was long predicted by theory. Our work uncovers a large free carrier contribution to the anomalous Hall effect resulting from the unique interplay between the Fermi surface and diverging Berry curvature in magnetic type-II WSMs. The authors study the field-induced ferromagnetic state of MnBi 2-x Sb x Te 4 by quantum oscillations and high-field Hall effect measurements. They confirm a single pair of type-II Weyl nodes, the long-sought “ideal” Weyl semimetal.

Collisional growth of cloud droplets is an essential yet uncertain process for drizzle and precipitation formation. To improve the quantitative understanding of this key component of cloud‐aerosol‐turbulence interactions, observational studies of collision‐coalescence in a controlled laboratory environment are needed. In an existing convection‐cloud chamber (the Pi Chamber), collisional growth is limited by low liquid water content and short droplet residence times. In this work, we use numerical simulations to explore various configurations of a convection‐cloud chamber that may intensify collision‐coalescence. We employ a large‐eddy simulation (LES) model with a size‐resolved (bin) cloud microphysics scheme to explore how cloud properties and the intensity of collision‐coalescence are affected by the chamber size and aspect ratio, surface roughness, side‐wall wetness, side‐wall temperature arrangement, and aerosol injection rate. Simulations without condensation and evaporation within the domain are first performed to explore the turbulence dynamics and wall fluxes. The LES wall fluxes are used to modify the Scalar Flux‐budget Model, which is then applied to demonstrate the need for non‐uniform side‐wall temperature (two side walls as warm as the bottom and the two others as cold as the top) to maintain high supersaturation in a tall chamber. The results of LES with full cloud microphysics reveal that collision‐coalescence is greatly enhanced by employing a taller chamber with saturated side walls, non‐uniform side‐wall temperature, and rough surfaces. For the conditions explored, although lowering the aerosol injection rate broadens the droplet size distribution, favoring collision‐coalescence, the reduced droplet number concentration decreases the frequency of collisions. Plain Language Summary A convection‐cloud chamber is useful in understanding how turbulence affects the interaction between aerosols and cloud droplets. The current convection‐cloud chamber (the Pi Chamber) is likely too small to explore how turbulence affects the collision‐coalescence among cloud droplets. To see whether collisional growth may be observable in a larger cloud chamber, we use numerical simulations to model the cloud droplet size distributions under several different configurations of the cloud chamber. The results suggest that the likelihood of detectable collisional growth increases significantly in a tall chamber with two warm and two cold saturated side walls and rough wall surfaces. Key Points Collision‐coalescence effects on a steady‐state droplet size distribution are stronger in a taller chamber Wet side walls are essential for maintaining cloud liquid water in a chamber with a low width‐to‐height aspect ratio Rougher surfaces increase surface heat and moisture fluxes, leading to larger liquid water content that promotes collision‐coalescence

Background and Objectives: Traumatic injuries are a major public health issue, being the leading cause of death in the U.S. Advancements in medical care, injury prevention, and regional trauma systems have improved survival rates, but there is limited information on outcomes for survivors. Blunt, sharp, and firearm injuries are the primary mechanisms in trauma forensics. This study examines patient outcomes for blunt, sharp, and firearm injuries over 20 years. Materials and Methods: De-identified data were collected from the TriNetX Research network in June 2024. Patients aged 18–90 were categorized by injury type (blunt, sharp, firearm) from 2004 to 2023. Trends were analyzed by stratifying the data into 20 consecutive one-year intervals. Mortality, blood transfusions, traumatic shock, hypovolemic shock, and acute post-hemorrhagic anemia were recorded annually. Statistical analysis was performed using One Way Repeated ANOVA and post hoc Tukey testing, with significance defined as p < 0.05. Results: The study included 1,205,350 blunt, 710,875 sharp, and 144,562 firearm injuries. Firearm injuries predominantly affected males (83%) and African Americans (51%), while blunt and sharp injuries showed more demographic variability. Looking at the 20-year trends, the average age of firearm and sharp injury patients decreased by 21% (48 ± 13 to 38 ± 15, p ≤ 0.0001) and 14% (49 ± 16 to 42 ± 18, p ≤ 0.0001), respectively, while blunt injury patient age did not change significantly. Mortality rates significantly decreased from 12% for firearm, 7% for sharp, and 6% for blunt injuries in 2004 to less than 1% in 2023 for all three injury mechanisms. Blood transfusions increased 450% (2% to 11%) for firearm injuries and increased 100% for sharp and blunt injuries (1% to 2%). Traumatic shock and hypovolemic shock incidences also increased by 100% for firearm injuries (3% to 6% and 1% to 2%, respectively), while sharp and blunt injuries did not change significantly. Acute post-hemorrhagic anemia increased from 3% to 19% for firearm injuries (533% relative increase), while sharp and blunt injuries remained around 3% for the past 20 years. Conclusions: The study reveals that with improved survival rates over the last 20 years, there has been a significant increase in shock-related morbidities and blood transfusion rates, particularly for firearm injuries. These findings can inform trauma care to enhance resuscitation efforts, optimize resource allocation, and improve mortality and outcomes for these injury mechanisms.

The shoulder may be an effective central site for continuous oxygen saturation (SpO2) monitoring but studies of shoulder-mounted pulse oximetry technology are limited. We hypothesized that an alternative location would be similar in function and user acceptance to a standard FDA-cleared finger-based pulse oximeter. We conducted a quantitative and descriptive pilot study of two prototype biosensor designs in patients with clinical suspicion of hypoxic episodes at an outpatient sleep center. Participants wore two prototype biosensors—the primary a shoulder-mounted adhesive and the secondary a combination ring–bracelet—in addition to a control FDA-approved finger-based pulse oximeter. We assessed the comfort of the devices based on a survey. We monitored 27 patients during an overnight polysomnography study. Participants rated the shoulder-mounted device more highly than the control device on a Likert scale survey of comfort (4.6 out of 5 versus 3.1 out of 5). Open-ended questionnaires showed that the two major criticisms of the control and ring devices were devices falling off and disruption to sleep, while only one participant commented on the shoulder device specifically. We also investigated SpO2 agreement between the primary shoulder-mounted prototype and the control finger-based pulse oximeter. This study confirms that alternative configurations for SpO2 monitoring offer potential as well-tolerated devices with preliminary findings of acceptable agreement. Problems with traditional pulse oximetry, such as false readings of hypoxia due to device removal or noisy data, were encountered less frequently in shoulder-mounted pulse oximetry than in the commercial finger-based device. Future directions include studies of additional populations that are at risk of respiratory collapse and surveys to elicit specific feedback on the configurations, whether positive or negative.

Chronic pain negatively impacts a range of sensory and affective behaviors. Previous studies have shown that the presence of chronic pain not only causes hypersensitivity at the site of injury but may also be associated with pain-aversive experiences at anatomically unrelated sites. While animal studies have indicated that the cingulate and prefrontal cortices are involved in this generalized hyperalgesia, the mechanisms distinguishing increased sensitivity at the site of injury from a generalized sitenonspecific enhancement in the aversive response to nociceptive inputs are not well known. Here we compared measured pain responses to peripheral mechanical stimuli applied to a site of chronic pain and at a pain-free site in participants suffering from chronic lower back pain (n = 15) versus pain-free control participants (n = 15). As expected, participants with chronic pain endorsed enhanced pain with mechanical stimuli in both back and hand. We further analyzed electroencephalographic (EEG) recordings during these evoked pain episodes. Brain oscillations in theta and alpha bands in the medial orbitofrontal cortex (mOFC) were associated with localized hypersensitivity, while increased gamma oscillations in the anterior cingulate cortex (ACC) and increased theta oscillations in the dorsolateral prefrontal cortex (dlPFC) were associated with generalized hyperalgesia. These findings indicate that chronic pain may disrupt multiple cortical circuits to impact nociceptive processing.

A large convection cloud chamber has been proposed for exploring aerosol–cloud–drizzle interactions under well‐controlled turbulent conditions. Recent theoretical and numerical studies suggest that a convection cloud chamber with two heated and two cooled sidewalls can significantly enhance the liquid water content and thus benefit drizzle initiation. However, a chamber with such a sidewall configuration develops stable stratification and extremely weak turbulence therein. In this study, we conduct large‐eddy simulations of a tall convection chamber with five different sidewall configurations consisting of alternating warm and cold patches. For each configuration, the total surface area of warm patches equals that of cold patches, resulting in the same expected cloud‐free supersaturation based on a flux budget model. Results show that changing the sidewall configuration, while keeping all other factors constant, can substantially enhance turbulent mixing and improve the uniformity of thermodynamic and cloud microphysical properties in the bulk region of the chamber. In addition, turbulence strength is positively correlated with liquid water content and negatively correlated with cloud droplet number concentration, consistent with theoretical predictions. Our results highlight the advantage of building a large cloud chamber using modular patches with individually controllable temperature and humidity to achieve well‐mixed conditions. Plain Language Summary Theoretical and numerical studies have suggested that cloud droplets in a tall convection cloud chamber with a height of about 10 m can collide with each other to form drizzle drops naturally—a key, but still not fully understood, process for warm rain precipitation. Due to the large height‐to‐width ratio, a previous study shows that a tall convection chamber with two hot sidewalls and another two cold sidewalls is needed to achieve high supersaturation and liquid water content that can benefit drizzle initiation. However, such a sidewall configuration would lead to weak turbulence and stable stratification in the bulk region of the chamber. This study shows that using tiled sidewalls consisting of alternating hot and cold patches can enhance turbulent mixing and the uniformity of cloud microphysical properties, while keeping other factors constant. In addition, increasing turbulent strength increases liquid water content but decreases cloud droplet number concentration, and their scaling relationships from the simulation are consistent with theoretical predictions. Key Points We conduct large‐eddy simulations of a tall convection chamber with tiled sidewalls configured with alternating warm and cold patches Changing tiled sidewall patterns alone can enhance turbulent mixing and microphysical uniformity in a convection cloud chamber Enhanced mixing correlates positively with liquid water content but negatively with number concentration, matching theoretical predictions

Recurrent neural networks have been shown to be effective architectures for many tasks in high energy physics, and thus have been widely adopted. Their use in low-latency environments has, however, been limited as a result of the difficulties of implementing recurrent architectures on field-programmable gate arrays (FPGAs). In this paper we present an implementation of two types of recurrent neural network layers—long short-term memory and gated recurrent unit—within the hls4ml framework. We demonstrate that our implementation is capable of producing effective designs for both small and large models, and can be customized to meet specific design requirements for inference latencies and FPGA resources. We show the performance and synthesized designs for multiple neural networks, many of which are trained specifically for jet identification tasks at the CERN Large Hadron Collider.