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Background and Objectives: Cardiovascular magnetic resonance (CMR) is emerging as an important imaging tool for sub-phenotyping and estimating left ventricular (LV) filling pressure (LVFP). The N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) is released from cardiac myocytes in response to mechanical load and wall stress. This study sought to investigate if CMR-derived LVFP is associated with the serum levels of NT-proBNP and, in addition, if it provides any incremental prognostic value in heart failure (HF). Materials and Methods: This study recruited 380 patients diagnosed with HF who underwent same-day CMR and clinical assessment between February 2018 and January 2020. CMR-derived LVFP was calculated, as previously, from long- and short-axis cines. During CMR assessment, serum NT-proBNP was measured. The pathological cut-offs were defined as follows: NT-proBNP ≥ 125 pg/mL and CMR LVFP > 15 mmHg. The incidence of HF hospitalisation was treated as a clinical outcome. Results: In total, 305 patients had NT-proBNP ≥ 125 pg/mL. Patients with raised NT-proBNP were older (54 ± 14 vs. 64 ± 11 years, p < 0.0001). Patients with raised NT-proBNP had higher LV volumes and mass. In addition, CMR LVFP was higher in patients with raised NT-proBNP (13.2 ± 2.6 vs. 15.4 ± 3.2 mmHg, p < 0.0001). The serum levels of NT-proBNP were associated with CMR-derived LVFP (R = 0.42, p < 0.0001). In logistic regression analysis, this association between NT-proBNP and CMR LVFP was independent of all other CMR variables, including LV ejection fraction, LV mass, and left atrial volume (coefficient = 2.02, p = 0.002). CMR LVFP demonstrated an independent association with the incidence of HF hospitalisation above NT-proBNP (hazard ratio 2.7, 95% confidence interval 1.2 to 6, p = 0.01). Conclusions: A CMR-modelled LVFP is independently associated with serum NT-proBNP levels. Importantly, it provides an incremental prognostic value over and above serum NT-proBNP levels. [ABSTRACT FROM AUTHOR]

Aims: Left ventricular filling pressure (LVFP) can be estimated from cardiovascular magnetic resonance (CMR). We aimed to investigate whether CMR‐derived LVFP is associated with signs, symptoms, and prognosis in patients with recently diagnosed heart failure (HF). Methods and results: This study recruited 454 patients diagnosed with HF who underwent same‐day CMR and clinical assessment between February 2018 and January 2020. CMR‐derived LVFP was calculated, as previously, from long‐ and short‐axis cines. CMR‐derived LVFP association with symptoms and signs of HF was investigated. Patients were followed for median 2.9 years (interquartile range 1.5–3.6 years) for major adverse cardiovascular events (MACE), defined as the composite of cardiovascular death, HF hospitalization, non‐fatal stroke, and non‐fatal myocardial infarction. The mean age was 62 ± 13 years, 36% were female (n = 163), and 30% (n = 135) had raised LVFP. Forty‐seven per cent of patients had an ejection fraction < 40% during CMR assessment. Patients with raised LVFP were more likely to have pleural effusions [hazard ratio (HR) 3.2, P = 0.003], orthopnoea (HR 2.0, P = 0.008), lower limb oedema (HR 1.7, P = 0.04), and breathlessness (HR 1.7, P = 0.01). Raised CMR‐derived LVFP was associated with a four‐fold risk of HF hospitalization (HR 4.0, P < 0.0001) and a three‐fold risk of MACE (HR 3.1, P < 0.0001). In the multivariable model, raised CMR‐derived LVFP was independently associated with HF hospitalization (adjusted HR 3.8, P = 0.0001) and MACE (adjusted HR 3.0, P = 0.0001). Conclusions: Raised CMR‐derived LVFP is strongly associated with symptoms and signs of HF. In addition, raised CMR‐derived LVFP is independently associated with subsequent HF hospitalization and MACE. [ABSTRACT FROM AUTHOR]

The United States National Aeronautics and Space Administration's (NASA's) mandate is a human mission to Mars in the 2030s and sustained exploration of Mars requires in situ resource utilization (ISRU). Exploiting the Martian water cycle (alongside perchlorate salts that depress water's freezing point to <213 K) and the available 95 vol.% atmospheric CO2, we detail an ultra‐low temperature (255 K) CO2–H2O electrolyzer to produce methane fuel and life‐supporting oxygen on Mars. Our polarization model fit experimental Martian brine electrolyzer performance and predicted CO2 electrolysis occurring at comparatively lower potentials (vs. water electrolysis) on Mars. A hypothetical 10‐cell, 100 cm2 electrode‐area‐per‐cell electrolyzer produced 0.45 g W−1 day−1 of CH4 and 3.55 g W−1 day−1 of O2 at 2 V/cell and 50% electrolyzer faradaic efficiency versus a best‐case production of 2.5 g W−1 day−1 of O2 by the Mars Oxygen in situ Resource Utilization Experiment (MOXIE) from NASA's Mars 2020 mission (MOXIE produces no fuel). Material performance requirements are presented to advance this technology as an energy‐efficient complement to MOXIE. [ABSTRACT FROM AUTHOR]

This study evaluates the capability of Navier–Stokes solvers in predicting forward and backward plunging breaking, including assessment of the effect of grid resolution, turbulence model, and VoF, CLSVoF interface models on predictions. For this purpose, 2D simulations are performed for four test cases: dam break, solitary wave run up on a slope, flow over a submerged bump, and solitary wave over a submerged rectangular obstacle. Plunging wave breaking involves high wave crest, plunger formation, and splash up, followed by second plunger, and chaotic water motions. Coarser grids reasonably predict the wave breaking features, but finer grids are required for accurate prediction of the splash up events. However, instabilities are triggered at the air–water interface (primarily for the air flow) on very fine grids, which induces surface peel-off or kinks and roll-up of the plunger tips. Reynolds averaged Navier–Stokes (RANS) turbulence models result in high eddy-viscosity in the air–water region which decays the fluid momentum and adversely affects the predictions. Both VoF and CLSVoF methods predict the large-scale plunging breaking characteristics well; however, they vary in the prediction of the finer details. The CLSVoF solver predicts the splash-up event and secondary plunger better than the VoF solver; however, the latter predicts the plunger shape better than the former for the solitary wave run-up on a slope case. [ABSTRACT FROM AUTHOR]

Introduction: Coronavirus disease 2019 (COVID-19) infections have strained hospital resources worldwide. As a result, many facilities have suspended elective operations and ambulatory procedures. As the incidence of new cases of COVID-19 decreases, hospitals will need policies and algorithms to facilitate safe and orderly return of normal activities. We describe the recommendations of a task force established in a multi-institutional healthcare system for resumption of elective operative and ambulatory procedures applicable to all hospitals and service lines., Methods: MedStar Health created a multidisciplinary task force to develop guidelines for resumption of elective surgeries/procedures. The primary focus areas included the establishment of a governance structure at each healthcare facility, prioritization of elective cases, preoperative severe acute respiratory syndrome coronavirus 2 testing, and an assessment of the needs and availability of staff, personal protective equipment, and other essential resources., Results: Each hospital president was tasked with establishing a local perioperative leadership team answering directly to them and granted the authority to prioritize elective surgery and ambulatory procedures. An elective surgery algorithm was established using a simplified Medically Necessary Time Sensitive score, with multiple steps requiring a "go/no-go" assessment based on local resources. In addition, mandatory preoperative COVID testing policies were developed and operationalized., Conclusions: Even when the COVID pandemic has passed, hospitals and surgical centers will require COVID screening and testing, case prioritization, and supply chain management to provide care essential to the surgical patient while protecting their safety and that of staff. Our guidelines consider these factors and are applicable to both tertiary academic medical centers and smaller community facilities., Competing Interests: Disclosure: The authors declare that they have nothing to disclose., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc.)