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Abstract: Purpose: The use of gated or ECG triggered MR is a well-established technique and developments in coil technology have enabled this approach to be applied to areas other than the heart. However, the image quality of gated (ECG or cine) versus non-gated or real-time has not been extensively evaluated in the mouth. We evaluate two image sequences by developing an automatic image processing technique which compares how well the image represents known anatomy. Methods: Four subjects practised experimental poly-syllabic sentences prior to MR scanning. Using a 1.5 T MR unit, we acquired comparable gated (using an artificial trigger) and non-gated sagittal images during speech. We then used an image processing algorithm to model the image grey along lines that cross the airway. Each line involved an eight parameter non-linear equation to model of proton densities, edges, and dimensions. Results: Gated and non-gated images show similar spatial resolution, with non-gated images being slightly sharper (10% better resolution, less than 1 pixel). However, the gated sequences generated images of substantially lower inherent noise, and substantially better discrimination between air and tissue. Additionally, the gated sequences demonstrate a very much greater temporal resolution. Conclusion: Overall, image quality is better with gated imaging techniques, especially given their superior temporal resolution. Gated techniques are limited by the repeatability of the motions involved, and we have shown that speech to a metronome can be sufficiently repeatable to allow high-quality gated magnetic resonance imaging images. We suggest that gated sequences may be useful for evaluating other types of repetitive movement involving the joints and limb motions.

This nationwide analysis shows that patients undergoing surgery with perioperative COVID-19 had higher risks of 30-day mortality & morbidity, especially thromboembolic events, compared to matched patients undergoing surgeries of similar urgency & complexity.

(Obstet Gynecol.2023;142:911–919)Research has clearly shown that health care outcomes are riddled with disparities surrounding race, but arguments exist about whether these disparities are due to biological differences, environmental, structural, or social elements of overall health, or systemic racism and inherent racial bias. Many observed differences in pregnancy outcomes are consistent even when correcting for poverty, educational status, or income level, suggesting that there are other factors that have not yet been identified. This commentary proposes that structural racism is a major contributing factor to health disparities between those of different races, including aspects such as access to healthy food options, psychosocial stressors, and safe and healthy living environments, and these differences will be manifest in the gut and vaginal microbiomes, thus affecting pregnancy-related outcomes related to the microbiome.

The standard method for calculating anti-neutrino emissions from a reactor involves knowing the fractional fission rates for the most important fissioning nuclides in the reactor. To calculate these rates requires detailed reactor physics calculations based upon the reactor design, fuel design, burnup dependent fuel composition, location of specific fuel assemblies in the core and detailed operational data from the reactor. This has only been published for a few reactors during specific time periods, whereas to be of practical use for anti-neutrino reactor monitoring it is necessary to be able to predict these on the publicly available information from any reactor, especially if using these data to subtract the anti-neutrino signal from other reactors to identify an undeclared reactor and monitor its operation. This paper proposes a method to estimate the fission fractions for a specific reactor based upon publicly available information and provides a database based upon a series of spent fuel inventory calculations using the FISPIN10 code and its associated data libraries.

The influence of liquid metal feeding on the flow and macrosegregation during direct chill (DC) casting of Al-4.5wt-%Cu billets is investigated. An analytical study for constricted inlets predicts that the inflow only reaches the bottom of the sump for narrow inlets, a result confirmed by steady-state axisymmetric simulations of equiaxed solidification. For wide inlets, and inlets using a combo bag, the inflow is swiftly entrained towards the chill and the final macrosegregation predictions are all similar. For narrow inlets without a combo bag, penetration of the thermal jet to the bottom of the sump locally delays solidification producing an inclination in the packed solid interface and the possible growth of columnar dendrites in this region.

ABSTRACTThe influence of liquid metal feeding on the flow and macrosegregation during direct chill (DC) casting of Al-4.5wt-%Cu billets is investigated. An analytical study for constricted inlets predicts that the inflow only reaches the bottom of the sump for narrow inlets, a result confirmed by steady-state axisymmetric simulations of equiaxed solidification. For wide inlets, and inlets using a combo bag, the inflow is swiftly entrained towards the chill and the final macrosegregation predictions are all similar. For narrow inlets without a combo bag, penetration of the thermal jet to the bottom of the sump locally delays solidification producing an inclination in the packed solid interface and the possible growth of columnar dendrites in this region.

Global health engagement missions are conducted to improve and protect the health of populations worldwide. Recognizing the strong link between health and security, the Armed Forces have increased the number of global health engagement missions over the last decade to support force health protection, medical readiness, enhance interoperability, improve host nation capacity building, combat global health threats (i.e., emerging infectious diseases), support humanitarian assistance and disaster relief efforts, as well as build trust and deepen professional medical relationships worldwide. These missions additionally support the US Global Health Security Agenda, US National Security Strategy, US National Defense Strategy and National Military Strategy.Although global health engagement missions are conducted by armed forces with numerous military units and geographical locations, military healthcare personnel assigned to US Naval hospital ships also perform a wide range of these missions. These missions comprise some of the largest global health engagement missions conducted, encompassing hundreds of subject matter expert exchanges, community health exchanges, medical symposiums, and side-by-side partnered healthcare in countries around the world. Military healthcare personnel who have completed past missions possess valuable knowledge related to ship-based global health engagement missions. Capturing and transferring this knowledge to future deployed personnel is important for future successful missions, but has remained a significant challenge. The purpose of this study was to capture and examine first-person accounts of experiential learning among active duty physicians, nurses, and hospital corpsmen who had participated in recent hospital ship-based global heath engagement missions.

Melt pool scale models of laser powder bed fusion (LPBF) offer insights into the process-structure-property relationships in additive manufacturing (AM). These models often neglect physical phenomena such as vapor cavity formation and fluid mechanics to reduce computational demands. Instead, volumetric heat source models are used to represent the effects that these phenomena have on the predicted melt pool dimensions. Generally, the dimensions and effective absorption of the volumetric heat source are calibrated to reproduce melt pool dimensions observed in metallographic cross sections taken from single-track experiments on bare plate. However, the transient nature of LPBF often deviates the melt pool dimensions from the assumed steady-state conditions of single-track experiments, motivating the need for a volumetric heat source model that more generally considers the dynamic relationship between melt pool shape and laser-material interactions. Here, we introduce a two-parameter volumetric heat source model that integrates several existing models into a generalized mathematical expression, providing independent control over the radial heat distribution via the parameter kand the volumetric shape of the heat source via the parameter m. This parameterization enables the calibration of melt pool shape predictions through simultaneous adjustment of these parameters, while keeping the radial heat source dimensions consistent with the experimental spot size (D4σ) and constraining the heat source depth and absorption to physically derived expressions for cavities. Consequently, the proposed volumetric heat source model adapts to changes in the local melt pool conditions due to scanning strategy and part geometry by dynamically adjusting the heat source depth and absorption. We demonstrate the capabilities of the proposed model through comparisons with a collection of experiments from the Additive Manufacturing Benchmark (AMBench).

Many fish exhibit rheotaxis, a behavior in which fish orient themselves relative to flow. Rheotaxis confers many benefits, including energetic cost savings and interception of drifting prey. Despite the fact that most species of fish school during at least some portion of their life, little is known about the importance of rheotactic behavior to schooling fish and, conversely, how the presence of nearby conspecifics affects rheotactic behavior. Understanding how rheotaxis is modified by social factors is thus of ecological importance. Here we present a mathematical model in the form of an all-to-all, coupled-oscillator framework over the non-Euclidean space of fish orientations to model group rheotactic behavior. Individuals in the model measure the orientation of their neighbors and the flow direction relative to their own orientation. These measures are corrupted by sensory noise. We study the effect of sensory noise and group size on internal (i.e., within the school) and external (i.e., with the flow) disagreement in orientation. We find that under noisy environmental conditions, increased group size improves rheotaxis. Results of this study have implications for understanding animal behavior, as well as for potential applications in bio-inspired engineering.

Background:: Whole-gland extirpation or irradiation is considered the gold standard for curative oncological treatment for localized prostate cancer, but is often associated with sexual and urinary impairment that adversely affects quality of life. This has led to increased interest in developing therapies with effective cancer control but less morbidity. We aimed to provide details of physician consensus on patient selection for prostate focal therapy (FT) in the era of contemporary prostate cancer management. Methods:: We undertook a four-stage Delphi consensus project among a panel of 47 international experts in prostate FT. Data on three main domains (role of biopsy/imaging, disease and patient factors) were collected in three iterative rounds of online questionnaires and feedback. Consensus was defined as agreement in ⩾80% of physicians. Finally, an in-person meeting was attended by a core group of 16 experts to review the data and formulate the consensus statement. Results:: Consensus was obtained in 16 of 18 subdomains. Multiparametric magnetic resonance imaging (mpMRI) is a standard imaging tool for patient selection for FT. In the presence of an mpMRI-suspicious lesion, histological confirmation is necessary prior to FT. In addition, systematic biopsy remains necessary to assess mpMRI-negative areas. However, adequate criteria for systematic biopsy remains indeterminate. FT can be recommended in D’Amico low-/intermediate-risk cancer including Gleason 4+3. Gleason 3+4 cancer, where localized, discrete and of favorable size represents the ideal case for FT. Tumor foci <1.5 ml on mpMRI or <20% of the prostate are suitable for FT, or up to 3 ml or 25% if localized to one hemi-gland. Gleason 3+3 at one core 1mm is acceptable in the untreated area. Preservation of sexual function is an important goal, but lack of erectile function should not exclude a patient from FT. Conclusions:: This consensus provides a contemporary insight into expert opinion of patient selection for FT of clinically localized prostate cancer.

Additive manufacturing (AM) may have many advantages over traditional casting and wrought methods, but our understanding of the various processes is still limited. Computational models are useful to study and isolate underlying physics and improve our understanding of the AM process-microstructure-property relations. However, these models necessarily rely on simplifications and parameters of uncertain value. These assumptions reduce the overall reliability of the predictive capabilities of these models, so it is important to estimate the uncertainty in model output. In doing so, we quantify the effect of model limitations and identify potential areas of improvement, a procedure made possible by uncertainty quantification (UQ). Here we highlight recent work which coupled and propagated statistical and systematic uncertainties from a melt pool transport model based in OpenFOAM, through a grain scale cellular automaton code. We demonstrate how a UQ framework can identify model parameters which most significantly impact the reliability of model predictions through both models and thus provide insight for future improvements in the models and suggest measurements to reduce output uncertainty.

Key scientific results from recent experiments, modeling tools, and heavy ion accelerator research are summarized that explore ways to investigate the properties of high energy density matter in heavy-ion-driven targets, in particular, strongly-coupled plasmas at 0.01 to 0.1 times solid density for studies of warm dense matter, which is a frontier area in high energy density physics. Pursuit of these near-term objectives has resulted in many innovations that will ultimately benefit heavy ion inertial fusion energy. These include: neutralized ion beam compression and focusing, which hold the promise of greatly improving the stage between the accelerator and the target chamber in a fusion power plant; and the Pulse Line Ion Accelerator (PLIA), which may lead to compact, low-cost modular linac drivers.

Many fish exhibit rheotaxis, a behavior in which fish orient themselves relative to flow. Rheotaxis confers many benefits, including energetic cost savings and interception of drifting prey. Despite the fact that most species of fish school during at least some portion of their life, little is known about the importance of rheotactic behavior to schooling fish and, conversely, how the presence of nearby conspecifics affects rheotactic behavior. Understanding how rheotaxis is modified by social factors is thus of ecological importance. Here we present a mathematical model in the form of an all-to-all, coupled-oscillator framework over the non-Euclidean space of fish orientations to model group rheotactic behavior. Individuals in the model measure the orientation of their neighbors and the flow direction relative to their own orientation. These measures are corrupted by sensory noise. We study the effect of sensory noise and group size on internal (i.e., within the school) and external (i.e., with the flow) disagreement in orientation. We find that under noisy environmental conditions, increased group size improves rheotaxis. Results of this study have implications for understanding animal behavior, as well as for potential applications in bio-inspired engineering.

The authors report on the establishment of the nation's first Organ Procurement Organization–based organ recovery facility with a goal of increasing efficiencies, reducing costs, and reducing procurement surgeon travel.

Transplant surgeons have historically traveled to donor hospitals, performing complex, time-sensitive procedures with unfamiliar personnel. This often involves air travel, significant delays, and frequently occurs overnight. In 2001, we established the nation’s first organ recovery center. The goal was to increase efficiency, reduce costs and reduce surgeon travel. Liver donors and recipients, donor costs, surgeon hours and travel time, from April 1, 2001 through December 31, 2011 were analyzed. Nine hundred and fifteen liver transplants performed at our center were analyzed based on procurement location (living donors and donation after cardiac death donors were excluded). In year 1, 36% (9/25) of donor procurements occurred at the organ procurement organization (OPO) facility, rising to 93% (56/60) in the last year of analysis. Travel time was reduced from 8 to 2.7 h (p < 0.0001), with a reduction of surgeon fly outs by 93% (14/15) in 2011. Liver organ donor charges generated by the donor were reduced by 37% overall for donors recovered at the OPO facility versus acute care hospital. Organs recovered in this novel facility resulted in significantly reduced surgeon hours, air travel and cost. This practice has major implications for cost containment and OPO national policy and could become the standard of care.

Liquid hydrogen has historically been limited in proximity to baseload liquefiers and research laboratories. This accessibility barrier is a primary limitation to the development of advanced aircraft and is exacerbated by recent trends in unmanned aerial systems to convert to electric propulsion systems. This article describes the design, construction, and commissioning of a self-contained, automated, and deployable liquid hydrogen production and fueling system. Housed within a mil-spec shipping container, the system utilizes a water purifier, proton exchange membrane electrolyzer, cryogenic refrigerator, and custom liquid hydrogen dewar. The system requires only water, electricity, and periodic helium purge gas input for continuous operation. Overall system performance specifications are provided. The system demonstrates the capability of field deployable hydrogen liquefiers and fueling systems.

ABSTRACTThe agent of Lyme disease, Borrelia burgdorferi, has a number of outer membrane proteins that are differentially regulated during its life cycle. In addition to their physiological functions in the organism, these proteins also likely serve different functions in invasiveness and immune evasion. In borreliae, as well as in other bacteria, a number of membrane proteins have been implicated in binding plasminogen. The activation and transformation of plasminogen into its proteolytically active form, plasmin, enhances the ability of the bacteria to disseminate in the host. Outer membrane vesicles of B. burgdorfericontain enolase, a glycolytic-cycle enzyme that catalyzes 2-phosphoglycerate to form phosphoenolpyruvate, which is also a known plasminogen receptor in Gram-positive bacteria. The enolase was cloned, expressed, purified, and used to generate rabbit antienolase serum. The enolase binds plasminogen in a lysine-dependent manner but not through ionic interactions. Although it is present in the outer membrane, microscopy and proteinase K treatment showed that enolase does not appear to be exposed on the surface. However, enolase in the outer membrane vesicles is accessible to proteolytic degradation by proteinase K. Samples from experimentally and tick-infected mice and rabbits as well as from Lyme disease patients exhibit recognition of enolase in serologic assays. Thus, this immunogenic plasminogen receptor released in outer membrane vesicles could be responsible for external proteolysis in the pericellular environment and have roles in nutrition and in enhancing dissemination.

The agent of Lyme disease, Borrelia burgdorferi, has a number of outer membrane proteins that are differentially regulated during its life cycle. In addition to their physiological functions in the organism, these proteins also likely serve different functions in invasiveness and immune evasion. In borreliae, as well as in other bacteria, a number of membrane proteins have been implicated in binding plasminogen. The activation and transformation of plasminogen into its proteolytically active form, plasmin, enhances the ability of the bacteria to disseminate in the host. Outer membrane vesicles of B. burgdorferi contain enolase, a glycolytic-cycle enzyme that catalyzes 2-phosphoglycerate to form phosphoenolpyruvate, which is also a known plasminogen receptor in Gram-positive bacteria. The enolase was cloned, expressed, purified, and used to generate rabbit antienolase serum. The enolase binds plasminogen in a lysine-dependent manner but not through ionic interactions. Although it is present in the outer membrane, microscopy and proteinase K treatment showed that enolase does not appear to be exposed on the surface. However, enolase in the outer membrane vesicles is accessible to proteolytic degradation by proteinase K. Samples from experimentally and tick-infected mice and rabbits as well as from Lyme disease patients exhibit recognition of enolase in serologic assays. Thus, this immunogenic plasminogen receptor released in outer membrane vesicles could be responsible for external proteolysis in the pericellular environment and have roles in nutrition and in enhancing dissemination.

Nanopores are a new class of low dimensional semiconductor nanostructures which have been recently proposed for use in lasers and other photonic applications. This paper provides an overview of patterned nanopore lattices with an emphasis on their electronic and optical properties. The ability to control nanopore properties by geometry and material composition are demonstrated. Two methods for controlled nanopore fabrication are presented and compared. Spectral characteristics of nanopore lasers are presented. Finite element numerical simulations are also performed to determine the band structure and emission properties of nanopores.

Abstract: Purpose: The use of gated or ECG triggered MR is a well-established technique and developments in coil technology have enabled this approach to be applied to areas other than the heart. However, the image quality of gated (ECG or cine) versus non-gated or real-time has not been extensively evaluated in the mouth. We evaluate two image sequences by developing an automatic image processing technique which compares how well the image represents known anatomy. Methods: Four subjects practised experimental poly-syllabic sentences prior to MR scanning. Using a 1.5 T MR unit, we acquired comparable gated (using an artificial trigger) and non-gated sagittal images during speech. We then used an image processing algorithm to model the image grey along lines that cross the airway. Each line involved an eight parameter non-linear equation to model of proton densities, edges, and dimensions. Results: Gated and non-gated images show similar spatial resolution, with non-gated images being slightly sharper (10% better resolution, less than 1 pixel). However, the gated sequences generated images of substantially lower inherent noise, and substantially better discrimination between air and tissue. Additionally, the gated sequences demonstrate a very much greater temporal resolution. Conclusion: Overall, image quality is better with gated imaging techniques, especially given their superior temporal resolution. Gated techniques are limited by the repeatability of the motions involved, and we have shown that speech to a metronome can be sufficiently repeatable to allow high-quality gated magnetic resonance imaging images. We suggest that gated sequences may be useful for evaluating other types of repetitive movement involving the joints and limb motions.

Experimental methods, apparatus, and practically useful theoretical analysis are provided for the coagulation‐based spinning of effectively unlimited lengths of carbon nanotube fibers having exceptional toughness and reasonably high strength. This spinning process fundamentally depends on the mechanical properties of intermediate gel state fibers, which we find are surprising elastic up to about 20 % strain and sufficiently strong for diverse processing methods. More specifically, we show that assemblies of these gel fibers can be used as intermediates for making nanotube sheets, large diameter fibers, and conformal coatings. When suitably processed, these composites (comprising many parallel solution‐spun nanotube fibers) have useful strength and extraordinary toughness.

Four control operations, each with paired pre-feed and no-pre-feed treatments, and comprising two baited with carrot and two with cereal, provided strong support for the hypothesis that pre-feeding produces higher possum kills than no pre-feeding. In these replicates, even where high kills were achieved, the modelled two- to three-fold extension of the period of population depression given by pre-feeding was sufficient to warrant the expense of the additional bait sown. The benefits of pre-feeding were clear-cut, and were greatest where poorest kills were achieved, irrespective of bait type. Pre-feeding is thus likely to reduce the probability of failure and should be considered a form of operational insurance.