A distributed bio-inspired method for multisite grid mapping

Computational grids assemble multisite and multiowner resources and represent the most promising solutions for processing distributed computationally intensive applications, each composed by a collection of communicating tasks. The execution of an application on a grid presumes three successive steps: the localization of the available resources together with their characteristics and status; the mapping which selects the resources that, during the estimated running time, better support this execution and, at last, the scheduling of the tasks. These operations are very difficult both because the availability and workload of grid resources change dynamically and because, in many cases, multisite mapping must be adopted to exploit all the possible benefits. As the mapping problem in parallel systems, already known as NP-complete, becomes even harder in distributed heterogeneous environments as in grids, evolutionary techniques can be adopted to find near-optimal solutions. In this paper an effective and efficient multisite mapping, based on a distributed Differential Evolution algorithm, is proposed. The aim is to minimize the time required to complete the execution of the application, selecting from among all the potential ones the solution which reduces the use of the grid resources. The proposed mapper is tested on different scenarios

Combined flow-based imaging assessment of optimal cardiac resynchronization therapy pacing vector: A case report

Background: There are still many pendent issues about the effective evaluation of cardiac resynchronization therapy impact on functional mitral regurgitation. In order to reduce the intrinsic difficulties of quantification of functional mitral regurgitation itself, an automatic quantification of real-time three-dimensional full-volume color Doppler transthoracic echocardiography was proposed as a new, rapid, and accurate method for the assessment of functional mitral regurgitation severity. Recent studies suggested that images of left ventricle flow by echo-particle imaging velocimetry could be a useful marker of synchrony. Echo-particle imaging velocimetry has shown that regional anomalies of synchrony/synergy of the left ventricle are related to the alteration, reduction, or suppression of the physiological intracavitary pressure gradients. Case summary: We describe a case in which the two technologies are used in combination during acute echocardiographic optimization of left pacing vector in a 63-year-old man, Caucasian, who showed worsening heart failure symptoms a few days after an implant, and the effect of the device\u2019s optimization at 6-month follow-up. Discussion: The degree of realignment of hemodynamic forces, with quantitative analysis of the orientation of blood flow momentum (\u3c6), can represent improvement of fluid dynamics synchrony of the left ventricle, and explain, with a new deterministic parameter, the effects of cardiac resynchronization therapy on functional mitral regurgitation. Realtime three-dimensional color flow Doppler quantification is feasible and accurate for measurement of mitral inflow, left ventricular outflow stroke volumes, and functional mitral regurgitation severity. Conclusion: This clinical case offers an innovative and accurate approach for acute echocardiographic optimization of left pacing vector. It shows clinical utility of combined three-dimensional full-volume color Doppler transthoracic echocardiography/echo-particle imaging velocimetry assessment to increase response to cardiac resynchronization therapy, in terms of reduction of functional mitral regurgitation, improving fluid dynamics synchrony of the left ventricle

A Distributed Bio-Inspired Method for Multisite Grid Mapping

Computational grids assemble multisite and multiowner resources and represent the most promising solutions for processing distributed computationally intensive applications, each composed by a collection of communicating tasks. The execution of an application on a grid presumes three successive steps: the localization of the available resources together with their characteristics and status; the mapping which selects the resources that, during the estimated running time, better support this execution and, at last, the scheduling of the tasks. These operations are very difficult both because the availability and workload of grid resources change dynamically and because, in many cases, multisite mapping must be adopted to exploit all the possible benefits. As the mapping problem in parallel systems, already known as NP-complete, becomes even harder in distributed heterogeneous environments as in grids, evolutionary techniques can be adopted to find near-optimal solutions. In this paper an effective and efficient multisite mapping, based on a distributed Differential Evolution algorithm, is proposed. The aim is to minimize the time required to complete the execution of the application, selecting from among all the potential ones the solution which reduces the use of the grid resources. The proposed mapper is tested on different scenarios

Magna Graecia transcatheter aortic valve implantation registry: data on contrast medium osmolality and postprocedural acute kidney injury

A comprehensive description of baseline characteristics, procedural features and outcomes related to the development of acute kidney injury (AKI) after transcatheter aortic valve implantation (TAVI) is reported in our research paper (Impact of contrast medium osmolality on the risk of acute kidney injury after transcatheter aortic valve implantation: insights from the Magna Graecia TAVI registry. Int J Cardiol. DOI: 10.1016/j.ijcard.2020.12.049). Three Italian heart centers were involved in this multicentric observational study. Between March 2011 and February 2019, a total of 888 patients underwent TAVI; according to the inclusion and exclusion criteria, 697 patients were included in the post-hoc analysis. This Data in Brief paper aims to report demographic, clinical, laboratory, echocardiographic, intraprocedural, periprocedural, postprocedural and follow-up data; all of them were prospectively collected from each patient's health record, whereas the analysis was performed retrospectively. Targets of this data analysis were: 1) to evaluate the impact of contrast medium (CM) osmolality on TAVI-related AKI; 2) to identify the most of risk factors involved in the development of such complication, and consequently in the occurrence of 1-year mortality; 3) to estimate the impact of CM osmolality on AKI in specific patient subgroups

Drug-eluting balloons for the treatment of the superficial femoral artery in-stent restenosis: 2-year follow-up.

OBJECTIVES: The aim of this prospective registry was to evaluate the safety and efficacy at 2-year follow-up of the use of drug-eluting balloons (DEBs) for the treatment of superficial femoral artery (SFA) in-stent restenosis (ISR). BACKGROUND: The use of DEBs for the treatment of SFA ISR is associated with a satisfactory primary patency rate at 1 year, but no data are available for longer follow-up. Unfortunately, when DEBs were used to treat SFA de novo lesions, the occurrence of restenosis increased by 50% between the first and the second years of follow-up. METHODS: From December 2009 to December 2010, 39 consecutive patients underwent percutaneous transluminal angioplasty of SFA ISR at our institution (Clinica Montevergine, Mercogliano, Italy). All patients underwent conventional SFA percutaneous transluminal angioplasty and final post-dilation with paclitaxel-eluting balloons (IN.PACT, Medtronic Inc., Minneapolis, Minnesota). Patients were evaluated for up to 24 months. RESULTS: During follow-up, 1 patient died of heart failure and another of sudden death, for a 2-years rate of cardiovascular mortality rate of 5.12 %. The primary patency rate at 2 years was 70.3% (11 of 37 patients experienced restenosis recurrence at 2-year follow-up). The treatment of complex ISR lesions (classes II and III) was associated with an increased rate of recurrent restenosis compared with class I (33.3 % and 36.3 % vs. 12.5%; p = 0.05). CONCLUSIONS: The data suggest that adjunctive use of DEBs for the treatment of SFA ISR is a safe and effective therapeutic strategy up to 2 years of follow-up

Impact of contrast medium osmolality on the risk of acute kidney injury after transcatheter aortic valve implantation: insights from the Magna Graecia TAVI registry

Background: Acute kidney injury (AKI) after transcatheter aortic valve implantation (TAVI) is frequent and associated with adverse outcomes and mortality; to date, in such setting of patients there is no consistent evidence that either low-osmolar contrast media (LOCM) or iso‐osmolar contrast medium (IOCM) are superior to the other in terms of renal safety. Methods: 697 consecutive patients not in hemodialysis treatment who underwent TAVI (327 males, mean age 81.01 ± 5.75 years, mean european system for cardiac operative risk evaluation II 6.17 ± 0.23%) were enrolled. According to osmolality of the different iodinated CM, the population was divided in 2 groups: IOCM (n = 370) and LOCM group (n = 327). Preoperatively, 40.54% of patients in IOCM vs 39.14% in LOCM group (p = 0.765) suffered from chronic kidney disease (CKD). Results: The incidence of AKI was significantly lower with IOCM (9.73%) than with LOCM (15.90%; p = 0.02), and such significant difference (p < 0.001) in postprocedural change of renal function parameters persisted at discharge too. The incidence of AKI was also significantly lower with IOCM in younger patients, without diabetes, anemia, coronary artery disease history, CKD, chronic or persistent atrial fibrillation, left ventricular ejection fraction ≤35%, and in patients with low operative mortality risk scores, receiving lower amounts of dye (p < 0.05 for all). Importantly, multivariate analysis identified LOCM administration as an independent risk factor for both AKI (p = 0.006) and 1-year mortality (p = 0.001). Conclusions: The use of IOCM have a favorable impact on renal function with respect to LOCM, but it should be considered especially for TAVI patients at lower AKI risk

Toward an Unsteady Aerodynamic ROM for Multiple Mach Regimes

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97065/1/AIAA2012-1708.pd

Predictors of carotid occlusion intolerance?during proximal protected?carotid artery?stenting.

OBJECTIVES: The aim of this study was to identify predictors of occlusion intolerance (OI) developing during proximal protected carotid artery stenting (CAS). BACKGROUND: The use of proximal embolic protection devices, such as endovascular occlusion, during CAS has been demonstrated to be particularly safe and effective. However, endovascular occlusion can expose the ipsilateral hemisphere to hypoperfusion and produce transient neurological symptoms (OI). METHODS: From March 2010 to March 2012, 605 consecutive patients underwent proximal protected CAS at our institution. To identify independent predictors of OI, a multivariate logistic regression model was developed that included all patients' clinical/angiographic and procedural characteristics. RESULTS: OI developed in a total of 184 patients (30.4%). Compared with patients in whom OI did not develop, those who experienced OI had lower occlusion pressure (OP) (42.3 ± 12.7 mm Hg vs. 61.9 ± 15.4 mm Hg, p < 0.001). Receiver-operating characteristic curve analysis demonstrated that OP was the most consistent predictor of OI with a C-statistic of 0.85 (95% confidence interval [CI]: 0.82 to 0.88) with best cutoff being ≤40 mm Hg (sensitivity, 68.5%; specificity, 93.3%). By logistic regression analysis, the most powerful independent predictor of OI developing was an OP ≤40 mm Hg (odds ratio: 33.2, 95% CI: 19.1 to 57.7) and the most powerful clinical predictor of such OP was the presence of contralateral internal carotid artery occlusion (odds ratio: 3.1, 95% CI: 1.5 to 6.2). CONCLUSIONS: OI may occur in as many as one-third of the patients undergoing proximal protected CAS. This event is more common in those patients with an OP ≤40 mm Hg. Patients presenting with concomitant occlusion of the contralateral internal carotid artery more frequently have an OP ≤40 mm Hg

Exoplanet Imaging Data Challenge, phase II: Characterization of exoplanet signals in high-contrast images

Today, there exists a wide variety of algorithms dedicated to high-contrast imaging, especially for the detection and characterisation of exoplanet signals. These algorithms are tailored to address the very high contrast between the exoplanet signal(s), which can be more than two orders of magnitude fainter than the bright starlight residuals in coronagraphic images. The starlight residuals are inhomogeneously distributed and follow various timescales that depend on the observing conditions and on the target star brightness. Disentangling the exoplanet signals within the starlight residuals is therefore challenging, and new post-processing algorithms are striving to achieve more accurate astrophysical results. The Exoplanet Imaging Data Challenge is a community-wide effort to develop, compare and evaluate algorithms using a set of benchmark high-contrast imaging datasets. After a first phase ran in 2020 and focused on the detection capabilities of existing algorithms, the focus of this ongoing second phase is to compare the characterisation capabilities of state-of-the-art techniques. The characterisation of planetary companions is two-fold: the astrometry (estimated position with respect to the host star) and spectrophotometry (estimated contrast with respect to the host star, as a function of wavelength). The goal of this second phase is to offer a platform for the community to benchmark techniques in a fair, homogeneous and robust way, and to foster collaborations.Comment: Submitted to SPIE Astronomical Telescopes + Instrumentation 2022, Adaptive Optics Systems VIII, Paper 12185-