Stochastic resetting by a random amplitude

Stochastic resetting, a diffusive process whose amplitude is reset to the origin at random times, is a vividly studied strategy to optimize encounter dynamics, e.g., in chemical reactions. Here we generalize the resetting step by introducing a random resetting amplitude such that the diffusing particle may be only partially reset towards the trajectory origin or even overshoot the origin in a resetting step. We introduce different scenarios for the random-amplitude stochastic resetting process and discuss the resulting dynamics. Direct applications are geophysical layering (stratigraphy) and population dynamics or financial markets, as well as generic search processes.Predoc Severo Ochoa 2018 grant PRE2018-084427; DFG Grant No. ME 1535/12-

Surgical Management for Advanced Heart Failure in Adults with Congenital Heart Disease

Adults with congenital heart disease (ACHD) have emerged as a new patient population that poses a variety of treatment and management obstacles. This chapter discusses the diagnosis of heart failure and treatment challenges faced by ACHD specifically addressing when to initiate mechanical circulatory support versus heart transplantation. It is evident that the ACHD population presents with a variety of unique challenges and considerations that still need to be explored. Addressing each of these issues will vastly change and improve how ACHD patients are approached from a treatment standpoint and ultimately provide more advantageous clinical options that can successfully handle the complexities presented by this population

Management of severe tricuspid valve regurgitation due to ruptured papillary muscle in a patient with mediastinitis early after heart transplant

OBJECTIVE: Even though severe tricuspid regurgitation is not uncommon after cardiac transplantation, primary severe tricuspid regurgitation is rare. We present such a case with additional complexities. METHODS: The patient was 44-year-old man with a HeartWare durable left ventricular assist device (Heartware Inc) who received a temporary right ventricular assist device (RVAD) with a ProtekDuo cannula (LivaNova Inc USA) for refractory ventricular fibrillation and underwent a heart transplant as United Network for Organ Sharing Status 1, in the presence of partially compensated cardiogenic shock, renal failure. Given complex re-operative surgery in a volume-overloaded patient with unknown pulmonary vascular resistance, an RVAD cannula was preserved and re- inserted during cardiac transplant. Postoperatively he required hemodialysis, had severe primary tricuspid regurgitation discovered after RVAD removal and developed Enterobacter mediastinitis. He underwent complex tricuspid valve repair for flail tricuspid leaflet due to ruptured papillary muscle likely due to RVAD cannula injury, after multiple mediastinal washouts and was followed by delayed chest reconstruction. RESULTS: The patient is doing well, 6 months after discharge to home, asymptomatic, without re-admissions, on renal recovery path, with no tricuspid regurgitation and good biventricular function. CONCLUSIONS: Replacing the tricuspid valve in presence of hemodialysis catheter, immunosuppression and mediastinitis could be high risk for endocarditis. Even though we have short-term follow-up, tricuspid valve repair can be an effective way of managing primary severe regurgitation especially when there is a desire or need to avoid valve replacement

Subdiffusive transport in intergranular lanes on the Sun. The Leighton model revisited

In this paper we consider a random motion of magnetic bright points (MBP) associated with magnetic fields at the solar photosphere. The MBP transport in the short time range [0-20 minutes] has a subdiffusive character as the magnetic flux tends to accumulate at sinks of the flow field. Such a behavior can be rigorously described in the framework of a continuous time random walk leading to the fractional Fokker-Planck dynamics. This formalism, applied for the analysis of the solar subdiffusion of magnetic fields, generalizes the Leighton's model.Comment: 7 page

Chimpanzee adenovirus vaccine protects against Zaire Ebola virus

AbstractThis study evaluated the use of a chimpanzee-based adenovirus vaccine in mouse and Guinea pigs models of Zaire Ebola virus (ZEBOV) infection. Vaccine vector expressing the envelope glycoprotein of ZEBOV was created from the molecular clone of chimpanzee adenovirus pan7 (AdC7). AdC7 vaccine stimulated robust T and B cell responses to ZEBOV in naïve mice inducing complete protection to an otherwise lethal challenge of ZEBOV. Complete protection to Zaire Ebola virus was also observed in Guinea pigs vaccinated with a relatively low dose of AdC7 (5 × 109/kg). Pre-existing immunity to AdHu5 was generated in mice following pre-exposure to AdHu5 or administration of pooled human immune globulin. Pre-existing immunity to human adenoviruses severely compromised the efficacy of the human AdHu5 vaccine but not the chimpanzee AdC7 vaccine. These results validate further development of Chimpanzee-based vaccine and highlight the impact of pre-existing immunity to the vaccine carrier

Hybridizing the 1/5-th Success Rule with Q-Learning for Controlling the Mutation Rate of an Evolutionary Algorithm

It is well known that evolutionary algorithms (EAs) achieve peak performance only when their parameters are suitably tuned to the given problem. Even more, it is known that the best parameter values can change during the optimization process. Parameter control mechanisms are techniques developed to identify and to track these values. Recently, a series of rigorous theoretical works confirmed the superiority of several parameter control techniques over EAs with best possible static parameters. Among these results are examples for controlling the mutation rate of the $(1+\lambda)$~EA when optimizing the OneMax problem. However, it was shown in [Rodionova et al., GECCO'19] that the quality of these techniques strongly depends on the offspring population size $\lambda$. We introduce in this work a new hybrid parameter control technique, which combines the well-known one-fifth success rule with Q-learning. We demonstrate that our HQL mechanism achieves equal or superior performance to all techniques tested in [Rodionova et al., GECCO'19] and this -- in contrast to previous parameter control methods -- simultaneously for all offspring population sizes $\lambda$. We also show that the promising performance of HQL is not restricted to OneMax, but extends to several other benchmark problems.Comment: To appear in the Proceedings of Parallel Problem Solving from Nature (PPSN'2020

Emergency Coronary Artery Bypass Grafting: Indications and Outcomes from 2003 through 2013

Emergency coronary artery bypass grafting (CABG) is associated with increased in-hospital mortality rates and adverse events. This study retrospectively evaluated indications and outcomes in patients who underwent emergency CABG. The Society of Thoracic Surgeons database for a single center (Jewish Hospital) was queried to identify patients undergoing isolated CABG. Univariate analysis was performed. From January 2003 through December 2013, 5,940 patients underwent CABG; 212 presented with emergency status. A high proportion of female patients (28.2%) underwent emergency surgery. Emergency CABG patients experienced high rates of intra-aortic balloon pump support, bleeding, dialysis, in-hospital death, and prolonged length of stay. The proportion of emergency coronary artery bypass grafting declined during years 2008–2013 compared with 2003–2007 (2.2% vs. 4.5%, P \u3c 0.001), but the incidence of angiographic accident (5.3% vs. 29.2%) increased as an indication. Ongoing ischemia remains the most frequent indication for emergency CABG, yet the incidence of angiographic accident has greatly increased. In-hospital mortality rates and adverse events remain high. If we look specifically at emergency CABG cases arising from angiographic accident, we find that 14 (15%) of all 93 emergency CABG deaths occurred in that subset of patients. Efforts to improve outcomes should therefore be focused on this high-risk group

Combined In Silico, In Vivo, and In Vitro Studies Shed Insights into the Acute Inflammatory Response in Middle-Aged Mice

We combined in silico, in vivo, and in vitro studies to gain insights into age-dependent changes in acute inflammation in response to bacterial endotoxin (LPS). Time-course cytokine, chemokine, and NO2-/NO3- data from "middle-aged" (6-8 months old) C57BL/6 mice were used to re-parameterize a mechanistic mathematical model of acute inflammation originally calibrated for "young" (2-3 months old) mice. These studies suggested that macrophages from middle-aged mice are more susceptible to cell death, as well as producing higher levels of pro-inflammatory cytokines, vs. macrophages from young mice. In support of the in silico-derived hypotheses, resident peritoneal cells from endotoxemic middle-aged mice exhibited reduced viability and produced elevated levels of TNF-α, IL-6, IL-10, and KC/CXCL1 as compared to cells from young mice. Our studies demonstrate the utility of a combined in silico, in vivo, and in vitro approach to the study of acute inflammation in shock states, and suggest hypotheses with regard to the changes in the cytokine milieu that accompany aging. © 2013 Namas et al