A rapid performance test for Superpave HMA mixtures

Permanent deformation and shear instability of Hot-Mix Asphalt (HMA) have been major concerns in the asphalt paving industry for a long time because permanent deformation failure, e.g., rutting and shoving, significantly reduces the ride quality of asphalt pavements and may even cause hazardous hydroplaning of vehicles. Furthermore, the fact that truck tire pressures are increasing and most of rutting occurs in the top 3~4 inches of the HMA layer requires the production of more rut-resistant and stable mixtures.;HMA mix design has escaped from its empirical stage and become more rational with the advent of the Superpave system. Superpave Level-I mix design, however, entirely depends on the volumetric properties of the mixture, without evaluating the potential performance of mixtures. In order to cope with the increasing demand for a simple performance test, extensive research has been conducted recently across the U.S. and new test methods and/or testing equipment have been introduced. Unfortunately the equipment is expensive, and the test procedures and sample preparations are rather complicated.;This study sought to develop a performance test that is rapid and easy to perform so that it can be routinely used during mix design and during construction to differentiate stable from unstable or rut-susceptible mixtures. In order to be cost-effective, the Rapid Performance Test (RPT) presented in this study utilizes the existing Superpave Gyratory Compactor (SGC), without the need for new, elaborate or sophisticated equipment.;However, it has been recognized that the behavior of HMA mixtures observed during the conventional compaction procedure cannot properly represent the performance of the mixture due to the unrealistically elevated compaction temperatures used in testing, and the confined movements of the mixture inside the rigid mold. Therefore the indenter of 4&inches;-diameter is inserted between the SGC loading platen and the mixture in order to allow plastic flow or lateral/upward movements of the mixture. Also, the RPT is performed at in-service temperatures to better capture realistic shear strength of HMA mixtures.;Extensive experiments were conducted on Iowa mixes and the RPT was evaluated by the dynamic creep test using the Nottingham Asphalt Tester (NAT)

Domain Generalization for Medical Image Analysis: A Survey

Medical Image Analysis (MedIA) has become an essential tool in medicine and healthcare, aiding in disease diagnosis, prognosis, and treatment planning, and recent successes in deep learning (DL) have made significant contributions to its advances. However, DL models for MedIA remain challenging to deploy in real-world situations, failing for generalization under the distributional gap between training and testing samples, known as a distribution shift problem. Researchers have dedicated their efforts to developing various DL methods to adapt and perform robustly on unknown and out-of-distribution data distributions. This paper comprehensively reviews domain generalization studies specifically tailored for MedIA. We provide a holistic view of how domain generalization techniques interact within the broader MedIA system, going beyond methodologies to consider the operational implications on the entire MedIA workflow. Specifically, we categorize domain generalization methods into data-level, feature-level, model-level, and analysis-level methods. We show how those methods can be used in various stages of the MedIA workflow with DL equipped from data acquisition to model prediction and analysis. Furthermore, we include benchmark datasets and applications used to evaluate these approaches and analyze the strengths and weaknesses of various methods, unveiling future research opportunities

Impact of successful restoration of sinus rhythm in patients with atrial fibrillation and acute heart failure: Results from the Korean Acute Heart Failure registry

Background: Restoring and maintaining sinus rhythm (SR) in patients with atrial fibrillation (AF) failed to show superior outcomes over rate control strategies in prior randomized trials. However, there is sparse data on their outcomes in patients with acute heart failure (AHF).Methods: From December 2010 to February 2014, 5,625 patients with AHF from 10 tertiary hospitals were enrolled in the Korean Acute Heart Failure registry, including 1,961 patients whose initial electrocardiogram showed AF. Clinical outcomes of patients who restored SR by pharmacological or electrical cardioversion (SR conversion group, n = 212) were compared to those of patients who showed a persistent AF rhythm (AF persistent group, n = 1,662).Results: All-cause mortality both in-hospital and during the follow-up (median 2.5 years) were significantly lower in the SR conversion group than in the AF persistent group after adjustment for risk factors (adjusted hazard ratio [HR]; 95% confidence interval [CI] = 0.26 [0.08–0.88], p = 0.031 and 0.59 [0.43–0.82], p = 0.002, for mortality in-hospital and during follow-up, respectively). After 1:3 propensity score matching (SR conversion group = 167, AF persistent group = 501), successful restoration of SR was associated with lower all-cause mortality (HR [95% CI] = 0.68 [0.49–0.93], p = 0.015), heart failure rehospitalization (HR [95% CI] = 0.66 [0.45–0.97], p = 0.032), and composite of death and heart failure rehospitalization (HR [95% CI] = 0.66 [0.51–0.86], p = 0.002).Conclusions: Patients with AHF and AF had significantly lower mortality in-hospital and during follow-up if rhythm treatment for AF was successful, underscoring the importance of restoring SR in patients with AHF

Recurrent Syncope Triggered by Temporal Lobe Epilepsy: Ictal Bradycardia Syndrome

Ictal asystole is potentially lethal, and known to originate from the involvement of limbic autonomic regions. Appropriate treatment must include an antiepileptic drug and the implantation of a pacemaker. We report the case of a 54-year-old male with recurrent syncope secondary to ictal asystole triggered by temporal lobe epilepsy. This was confirmed by combined Holter and video-electroencephalogram monitoring