Kennedy has argued that alpha rhythm recordings are artifacts caused by the mechanical pulsation (choroid plexus "pump") of a gel (the living brain) with different electrical potentials. This paper has been republished in a recent collection by Evans and Robertson. Kennedy's hypothesis seemed insufficiently supported, and contradicted the consensus concerning the origin of alpha waves which exi...

During the past 2 decades, high-resolution ultrasonography (US) has been increasingly utilized in the diagnosis of musculoskeletal trauma and diseases with results comparable with MR imaging. US has an advantage over other cross-sectional modalities in many circumstances due to its superior spatial resolution and ability to allow dynamic assessment. When performing musculoskeletal US, the exami...

The purpose of this paper is to introduce the principles of PET/CT imaging and describe the artifacts associated with it. PET/CT is a new imaging modality that integrates functional (PET) and structural (CT) information into a single scanning session, allowing excellent fusion of the PET and CT images and thus improving lesion localization and interpretation accuracy. Moreover, the CT data can ...

Any artifact in the HRV series may interfere with analysis of the signal. The artifacts within HRV signals can be divided into technical and physiological artifacts. The technical artifacts can include missing or additional QRS complex detections and error in R-wave occurrence time. These artifacts may be due to measurement artifacts or the computational algorithm. The physiological artifacts, ...

Evaluating complex Natural Language Processing (NLP) systems can prove extremely difficult. In many cases, the best one can do is to evaluate these systems indirectly, by looking at the impact they have on the performance of the downstream use case. For complex end-to-end systems, these metrics are not always enlightening, especially from the perspective of NLP failure analysis, as component in...

The Prediction Error Filter (PEF) is a widely used tool in various geophysical applications such as signal-noise separation and interpolation of missing data. Over the years, SEP has developed tools to estimate non-stationary Prediction Error Filters. Non-stationary PEFs are successfully used for multiple removal, ground-roll attenuation, and in other geophysical problems. I apply a non-station...