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Abstract An array of surface drifters deployed ahead of Hurricane Michael measured the surface temperature, pressure, directional wind and wave spectra, and surface currents one day before it made landfall as a Category 5 Hurricane. The drifters, 25–50 km apart, spanned two counter‐rotating ocean eddies as Hurricane Michael rapidly intensified. The drifters measured the shift of wave energy between frequency bands in each quadrant of the storm, the response of upper ocean currents, and the resulting cold wake following Michael's passage. Wave energy was greatest in the front quadrants and rapidly decreased in the left‐rear quadrant, where wind and wave energy were misaligned, and components of the wave field were aligned with currents. Hurricane Michael's wave field agreed with previous studies of nondirectional wave spectra across multiple tropical cyclones but had some unique characteristics. The analysis demonstrates how co‐located surface wind and wave observations can complement existing airborne and satellite observations.

The static equilibrium properties of a spool, resting on an incline and subject to the tension exerted by a string wrapped around the core cylinder, are studied by means of Newtonian mechanics. The overall behaviour of this system is imagined to be similar to that of a doggie kept on a leash. Starting from the well-known mechanical properties of the spool on a horizontal plane, this analogy is used to construct an inquiry-based-learning lecture adopting the BSCS 5E instructional model. In this approach the static properties of the spool on the incline are used to conceive an Extend phase.

Quantum-enhanced auxiliary field quantum Monte Carlo (QC-AFQMC) uses output from a quantum computer to increase the accuracy of its classical counterpart. The algorithm requires the estimation of overlaps between walker states and a trial wavefunction prepared on the quantum computer. We study the applicability of this algorithm in terms of the number of measurements required from the quantum computer and the classical costs of post-processing those measurements. We compare the classical post-processing costs of state-of-the-art measurement schemes using classical shadows to determine the overlaps and argue that the overall post-processing cost stemming from overlap estimations scales like $\mathcal{O}(N^9)$ per walker throughout the algorithm. With further numerical simulations, we compare the variance behavior of the classical shadows when randomizing over different ensembles, e.g. Cliffords and (particle-number restricted) matchgates beyond their respective bounds, and uncover the existence of covariances between overlap estimations of the AFQMC walkers at different imaginary time steps. Moreover, we include analyses of how the error in the overlap estimation propagates into the AFQMC energy and discuss its scaling when increasing the system size.

Abstract Background Temporary pacing is necessary in pacemaker‐dependent patients after transvenous lead extraction (TLE) for cardiac implantable electronic device infection. In case of unavailability of other accesses, we propose to use the ipsilateral subclavian access (ISA) combined with a standard permanent active fixation lead for the temporary pacemaker and present preliminary data. Methods We consecutively enrolled patients undergoing TLE who received a temporary pacemaker using the ISA between August 2016 and April 2020 at our centre. Results During the observation period, 36 patients undergoing TLE for pocket infection (72.2%), endocarditis (25.0%) or other causes received a temporary pacemaker over the ISA. Their mean age was 77.0 ± 10.7 years, and 13.9% were female. Complete TLE was achieved in 94.4%. There were no major periprocedural complications. Intra‐hospital mortality was 11.1%. Pocket revision was performed in 19.4%. During long‐term follow‐up (23 ± 13 months), 8.3% had a relapse of local pocket infection and 2.8% needed rehospitalization for reintervention. Conclusions Temporary pacing using a standard permanent active fixation lead using the ISA is a convenient alternative to conventional venous accesses. However, risks of implanting a lead into a previously infected area have to be taken into account.

Abstract The Somali Current system in the western Arabian Sea reverses seasonally with the South Asian Monsoon and is associated with localized upwelling cells or cold wedges during the summer southwest monsoon. Drifter trajectories in boreal summer and fall 2014 provide rare observational evidence that the northward Somali Current and associated cold wedges can persist into the boreal fall intermonsoon period. The near‐surface circulation and sea surface temperatures further suggest that the wedge‐like surface signatures may intermittently be capped and then reappear at a later time. Our observations show that the northward Somali Current system rapidly decayed within 1 week after the onset of the winter northeast monsoon and the arrival of a cyclonic eddy at the coast in early November 2014. This eddy may not only have affected regional ocean‐atmosphere interactions but also biogeochemical processes and the marine ecosystem through the transport of water properties and locally induced upwelling.

Abstract Measuring vertical motions represent a challenge as they are typically 3–4 orders of magnitude smaller than the horizontal velocities. Here, we show that surface vertical velocities are intensified at submesoscales and are dominated by high frequency variability. We use drifter observations to calculate divergence and vertical velocities in the upper 15 m of the water column at two different horizontal scales. The drifters, deployed at the edge of a mesoscale eddy in the Alboran Sea, show an area of strong convergence (O(f)) associated with vertical velocities of −100 m day−1. This study shows that a multilayered‐drifter array can be an effective tool for estimating vertical velocity near the ocean surface.

Abstract In recent years the emergence of high-performance virtual reality (VR) technology has opened up new possibilities for the examination of context effects in psychological studies. The opportunity to create ecologically valid stimulation in a highly controlled lab environment is especially relevant for studies of psychiatric disorders, where it can be problematic to confront participants with certain stimuli in real life. However, before VR can be confidently applied widely it is important to establish that commonly used behavioral tasks generate reliable data within a VR surrounding. One field of research that could benefit greatly from VR-applications are studies assessing the reactivity to addiction related cues (cue-reactivity) in participants suffering from gambling disorder. Here we tested the reliability of a commonly used temporal discounting task in a novel VR set-up designed for the concurrent assessment of behavioral and psychophysiological cue-reactivity in gambling disorder. On 2 days, thirty-four healthy non-gambling participants explored two rich and navigable VR-environments (neutral: café vs. gambling-related: casino and sports-betting facility), while their electrodermal activity was measured using remote sensors. In addition, participants completed the temporal discounting task implemented in each VR environment. On a third day, participants performed the task in a standard lab testing context. We then used comprehensive computational modeling using both standard softmax and drift diffusion model (DDM) choice rules to assess the reliability of discounting model parameters assessed in VR. Test–retest reliability estimates were good to excellent for the discount rate log(k), whereas they were poor to moderate for additional DDM parameters. Differences in model parameters between standard lab testing and VR, reflecting reactivity to the different environments, were mostly numerically small and of inconclusive directionality. Finally, while exposure to VR generally increased tonic skin conductance, this effect was not modulated by the neutral versus gambling-related VR-environment. Taken together this proof-of-concept study in non-gambling participants demonstrates that temporal discounting measures obtained in VR are reliable, suggesting that VR is a promising tool for applications in computational psychiatry, including studies on cue-reactivity in addiction.

Efficient representations of the Hamiltonian, such as double factorization, drastically reduce the circuit depth or the number of repetitions in error corrected and noisy intermediate-scale quantum (NISQ) algorithms for chemistry. We report a Lagrangian-based approach for evaluating relaxed one- and two-particle reduced density matrices from double factorized Hamiltonians, unlocking efficiency improvements in computing the nuclear gradient and related derivative properties. We demonstrate the accuracy and feasibility of our Lagrangian-based approach to recover all off-diagonal density matrix elements in classically simulated examples with up to 327 quantum and 18 470 total atoms in QM/MM simulations with modest-sized quantum active spaces. We show this in the context of the variational quantum eigensolver in case studies, such as transition state optimization, ab initio molecular dynamics simulation, and energy minimization of large molecular systems. [ABSTRACT FROM AUTHOR]

BACKGROUND: Epicardial approach in ventricular tachycardia (VT) ablation is still regarded as a second-step strategy, due to the risk of complications. We evaluated the frequency that epicardial ablation targets were identified and ablation performed following pericardial access compared with unnecessary pericardial access for different VT causes and potential markers of epicardial VT. METHODS: All VT ablation procedures including epicardial approach over a 10-year period were included. First-line epicardial approach was indicated in arrhythmogenic right ventricular cardiomyopathy (ARVC) and postmyocarditis VT; in patients with idiopathic dilated cardiomyopathy (IDCM) and postmyocardial infarction, indications resulted from available imaging techniques or 12-lead VT morphology. The epicardial approach was considered useful if epicardial ablation was performed after epicardial mapping. Feasibility, complications, and long-term outcome were reported. RESULTS: Four hundred and eighty-eight subjects with a median age of 60 years (interquartile range, 47–65) and of left ventricle ejection fraction 41% (interquartile range, 30–55) underwent 626 epicardial VT ablations. Percutaneous access had a success rate of 92.2% and a complication rate of 3.6%. Overall, epicardial approach was, respectively, indicated to 11.8% of postmyocardial infarction patients, 49.5% in IDCM, 94% in myocarditis, and 90.7% in ARVC. Epicardial ablation at the first ablation attempt was performed in 9.3% of postmyocardial infarction patients, 28.8% in IDCM, 86.5% in myocarditis, and 81.3% in patients with ARVC. In first-line epicardial group, ARVC and myocarditis showed the highest odds for epicardial ablation (OR, 4.057 [95% CI, 1.299–8.937]; P=0.007; OR, 3.971 [95% CI, 1.376–11.465]; P=0.005, respectively). IDCM independently predicted unnecessary epicardial approach (OR, 2.7 [95% CI, 1.7–4.3]; P<0.001). After a follow-up of 41 months (interquartile range, 19–64), patients with IDCM experienced higher rate of recurrences and mortality compared with other causes. CONCLUSIONS: Epicardial approach is integral part of ablation armamentarium regardless of the VT cause, with high feasibility and low complication rate in experienced centers. Our data support its use at first ablation attempt in VTs related to ARVC and myocarditis. [ABSTRACT FROM AUTHOR]

Observing the bouncing of a marble on a table is a rather common experience. The tic-tac sound of the rigid ball, nevertheless, carries quite a pleasant surprise. In fact, by measuring the total time of bouncing [delta]t, the coefficient of restitution can be estimated. As is well known, in an inelastic collision the kinetic energy is not conserved, and therefore the speed decreases. The speeds v[subscript i] and v[subscript f], before and after the collision occurs, respectively, are related as follows:[nu][subscript f]=[epsilon][nu][subscript i], (1) where [epsilon] < 1. By measuring the initial height h[subscript 0] from which the marble is released, we find that [equation omitted], (2) where g is the acceleration due to gravity and T is the total time from initial release until the ball stops bouncing.

An array of surface drifters deployed ahead of Hurricane Michael measured the surface temperature, pressure, directional wind and wave spectra, and surface currents one day before it made landfall as a Category 5 Hurricane. The drifters, 25–50 km apart, spanned two counter‐rotating ocean eddies as Hurricane Michael rapidly intensified. The drifters measured the shift of wave energy between frequency bands in each quadrant of the storm, the response of upper ocean currents, and the resulting cold wake following Michael's passage. Wave energy was greatest in the front quadrants and rapidly decreased in the left‐rear quadrant, where wind and wave energy were misaligned, and components of the wave field were aligned with currents. Hurricane Michael's wave field agreed with previous studies of nondirectional wave spectra across multiple tropical cyclones but had some unique characteristics. The analysis demonstrates how co‐located surface wind and wave observations can complement existing airborne and satellite observations. Plain Language Summary: Lagrangian drifters were air‐deployed ahead of Hurricane Michael and measured the direction and strength of waves and surface wind, sea surface temperature, and sea‐level pressure as the storm transited through the central Gulf of Mexico. As Hurricane Michael passed over the drifters, the drifters observed the cyclonic structure of the wind, the shift of wave energy from swell to wind‐sea, and the relative mismatch in direction of wind, waves, and ocean currents. In the rear quadrants of the storm, low‐frequency waves opposed the wind direction. The drifters, caught in counter‐rotating eddies, were ultimately entrained in different sides of the storm. The observations illustrate the importance of a suite of in situ surface observations to complement airborne observing strategies of tropical cyclones. Key Points: Ten surface drifters measured temperature, pressure, currents, directional wave spectra, and wind under Hurricane MichaelWave energy was greatest in the front quadrants with misalignment of wave energy by frequency band in rear‐quadrants of the stormWaves agreed with fetch‐limited wave growth and there were significant differences in wind‐wave‐current alignment in each quadrant [ABSTRACT FROM AUTHOR]

Rossella De Luca,1 Livio Blasi,2 Massimiliano Alù,2 Valerio Gristina,1 Giuseppe Cicero1 1Department of Surgical, Oncological and Oral Sciences, Section of Medical Oncology, University of Palermo, Palermo, Italy; 2Medical Oncology Unit, ARNAS Hospital Civico, Di Cristina, Benfratelli, Palermo, Italy Purpose: Pancreatic carcinoma is the neoplasia with the major mortality, and main standard treatments in this cancer increase survival but do not lead to complete recovery of the patient. The aim of this study was to evaluate the efficacy of Abraxane® (nab-paclitaxel) in Italian patients with metastatic pancreatic cancer (MPC).Patients and methods: We conducted a retrospective analysis of 80 patients. Overall survival (OS) was the primary end point for evaluating the efficacy of nab-paclitaxel in combination with gemcitabine treatment, while carbohydrate antigen 19-9 (CA 19-9) reduction, safety, progression-free survival (PFS), overall response rate and reduction in pain were secondary end points.Results: The median OS was 8 months, and the median PFS was 5 months. A considerable difference in CA 19-9 before and after treatment was observed. Descriptive and correlation analyses were done to examine the relationship between CA 19-9 response and OS. Linear regression analysis between OS and CA 19-9 response revealed that CA 19-9 is an important predictor of OS, showing a positive correlation.Conclusion: Nab-paclitaxel is a well-tolerated and effective treatment for patients affected by MPC. The drug showed an improved tolerability profile, significant pain relief and an increase in survival rate. Keywords: Abraxane, chemotherapy, pancreatic carcinoma, metastasis, CA 19-9, pain, overall survival

Ocean boundary current systems are key components of the climate system, are home to highly productive ecosystems, and have numerous societal impacts. Establishment of a global network of boundary current observing systems is a critical part of ongoing development of the Global Ocean Observing System. The characteristics of boundary current systems are reviewed, focusing on scientific and societal motivations for sustained observing. Techniques currently used to observe boundary current systems are reviewed, followed by a census of the current state of boundary current observing systems globally. The next steps in the development of boundary current observing systems are considered, leading to several specific recommendations.