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The evolving Great Power Competition among the primary players in the global power system greatly challenges our nation's ability to deter aggression on a global scale (The White House, 2022). [...]

Spherical tokamaks have many desirable features that make them an attractive choice for a future fusion power plant. Power-plant viability is intrinsically related to plasma heat and particle confinement, and this is often determined by the level of micro-instability-driven turbulence. Accurate calculation of the properties of turbulent microinstabilities is therefore critical for tokamak design; however, the evaluation of these properties is computationally expensive. The considerable number of geometric and thermodynamic parameters and the high resolutions required to accurately resolve these instabilities make repeated use of direct numerical simulations in integrated modeling workflows extremely computationally challenging and create the need for fast, accurate, reduced-order models. This paper outlines the development of a data-driven reduced-order model, often termed a surrogate model for the properties of micro-tearing modes (MTMs) across a spherical tokamak reactor-relevant parameter space utilizing Gaussian process regression and classification, techniques from machine learning. These two components are used in an active learning loop to maximize the efficiency of data acquisition, thus minimizing computational cost. The high-fidelity gyrokinetic code GS2 is used to calculate the linear properties of the MTMs: the mode growth rate, frequency, and normalized electron heat flux, and core components of a quasi-linear transport model. Data cross-validation and direct validation on unseen data are used to ascertain the performance of the resulting surrogate models. [ABSTRACT FROM AUTHOR]

Introduction: In recent years, health psychology has received significant attention within the health sector, due to its application to understanding influences on health and well‐being and translation of health psychology into interventions to support behaviour change. The number of health psychologists in public health and healthcare settings is growing but remains limited, and is it unclear why. This study aimed to explore the views of potential and current employers of health psychologists, to elucidate barriers and facilitators of employing health psychologists in healthcare settings. Methods: Semi‐structured interviews were carried out to explore the experiences of working with and/or employing health psychologists. Opportunities and barriers were explored for increasing access to health psychology expertise in the NHS and public health. Interviews were analysed using inductive thematic analysis. Results: Fifteen participants took part in interviews. Participants were mid‐senior‐level professionals working in varied healthcare settings and/or academic institutions. The majority had experience of health psychology/working with health psychologists, whilst others had limited experience but an interest in employing health psychologists. Three key themes were identified: (1) the organizational fit of health psychologists, (2) perception of competition for roles and (3) ideas for changing hearts, minds and processes. Conclusion: Barriers exist to employing health psychologists in healthcare settings. These barriers include misunderstandings of the role of health psychologists and the need to preserve other disciplines due to perceived competition. Recommendations for change included showcasing the benefits and skills of health psychologists and having transparent conversations with employees and multi‐disciplinary colleagues about roles. [ABSTRACT FROM AUTHOR]

Introduction: In metabolic surgery, hemorrhage is the most common major complication. This study investigated whether peroperative administration of tranexamic acid (TXA) reduced the risk of hemorrhage in patients undergoing laparoscopic sleeve gastrectomy (SG). Methods: In this double-blind randomized controlled trial, patients undergoing primary SG in a high-volume bariatric hospital were randomized (1:1) to receive 1500-mg TXA or placebo peroperatively. Primary outcome measure was peroperative staple line reinforcement using hemostatic clips. Secondary outcome measures were peroperative fibrin sealant use and blood loss, postoperative hemoglobin, heart rate, pain, major and minor complications, length of hospital stay (LOS), side effects of TXA (i.e., venous thrombotic event (VTE)) and mortality. Results: In total, 101 patients were analyzed and received TXA (n = 49) or placebo (n = 52). There was no statistically significant difference in hemostatic clip devices used in both groups (69% versus 83%, p = 0.161). TXA administration showed significant positive changes in hemoglobin levels (millimoles per Liter; 0.55 versus 0.80, p = 0.013), in heart rate (beats per minute; -4.6 versus 2.5; p = 0.013), in minor complications (Clavien–Dindo ≤ 2, 2.0% versus 17.3%, p = 0.016), and in mean LOS (hours; 30.8 versus 36.7, p = 0.013). One patient in the placebo-group underwent radiological intervention for postoperative hemorrhage. No VTE or mortality was reported. Conclusion: This study did not demonstrate a statistically significant difference in use of hemostatic clip devices and major complications after peroperative administration of TXA. However, TXA seems to have positive effects on clinical parameters, minor complications, and LOS in patients undergoing SG, without increasing the risk of VTE. Larger studies are needed to investigate the effect of TXA on postoperative major complications. [ABSTRACT FROM AUTHOR]

The grain size of 3Y-TZP is critical because it must remain below a certain size in order to remain tetragonal during aging in the oral cavity. However, fabrication protocols regularly do not accommodate this critical size factor. Nevertheless, grain size measurements generally are not considered or undertaken. Further, when they are, they are thermally etched, which alters the material by grain growth. The didactic purpose of the present work is to provide a strategy for the application of suitable experimental methods for the examination of grain growth in 3Y-TZP, without the risk of grain growth during thermal etching. Examination of the effects of the different applicable thermal conditions is done in order to demonstrate the extents of grain growth in dental restorations following sintering, layering, and glazing. 3Y-TZP nanoscale powders were prepared by coprecipitation using aqueous solutions of zirconyl nitrate and yttrium nitrate, precipitated by ammonium hydroxide, and calcined at 800 °C. Uniaxially and cold isostatically pressed disks were bisque-fired at 800 °C for 2 h, after which they were planed and polished (0.1 μm). The 27 samples were sintered at 1400 ºC, 1500 ºC, or 1600 °C for 1, 2, or 4 h. They then were post-treated by annealing at 750 °C for 1 min under mechanical vacuum and then by post-annealing at 750 °C for 1 min in air. As the pre-polish was retained following sintering, SEM images could be used to determine the grain sizes by standard grain size measurement methods without having to impose thermal etching. These data then were implemented in a grain growth kinetics assessment. The pre-polishing procedure and SEM imaging were successful in enabling accurate grain size measurements without sample alteration. The grain growth as a function of temperature and time exhibited trends approximately logarithmic and linear, respectively. The diffusion mechanism was suggested to be of boundary control by a high-solubility solute in a doped system. Significantly, only sintering at 1400 °C for 1–2 h retained the grain size below the critical limit of ~ 300 nm for resistance to aging in the oral cavity. Also, significantly, ~ 7% grain growth, with a range of 2–14%, occurred during the modest thermal conditions used for both annealing and post-annealing. Sintering, annealing, and post-annealing reduce the number of grain boundaries and hence reduce light scattering, resulting in increasing translucency. Further, the use of the lower sintering temperature of 1400 °C still can yield a very high bulk density (≥ 99.62%), but with a relative increase in light scattering and reduced translucency, making this more suitable for masking dark stump shades. More critically, this sintering temperature for only 1–2 h is necessary in order to avoid risk of the tetragonal → monoclinic phase transformation during the aging process. Further, these conditions are sufficient to allow a limited number of layering and glazing procedures. [ABSTRACT FROM AUTHOR]