Background: Allogeneic blood transfusion in patients undergoing total joint arthroplasty (TJA) has been shown tonegatively affect patient outcomes. This study aimed to examine if there is a correlation between operative time and theneed for allogeneic blood transfusions during TJA.Methods: We performed a retrospective review of 866 patients who underwent primary TJA during a o...

Background: Functional electrical stimulation (FES) is the most commonly used system for restoring functions after spinal cord injury (SCI). Objective: In this study we investigated feedback PID and feedforward-feedback P-PID controllers for regulating the elbow joint angle. Methods: The controllers were tuned based on a nonlinear muculoskeletal model containing two links, one joint with one de...

Cracking sounds emitted from human synovial joints have been attributed historically to the sudden collapse of a cavitation bubble formed as articular surfaces are separated. Unfortunately, bubble collapse as the source of joint cracking is inconsistent with many physical phenomena that define the joint cracking phenomenon. Here we present direct evidence from real-time magnetic resonance imagi...

Originally coined by the sensory psychologist Roger Shepard in the 1960's, chroma transforms frequency into octave equivalence classes. By extending the concept of chroma to chroma strength and how it varies over time, we have demonstrated the utility of chroma in simplifying the processing and representation of signals dominated by harmonically-related narrowband components. These investigatio...

This work was funded in part by the US Air Force Office of Scientific Research under grant F49620-01-1-0446. ABSTRACT Filtering in time-frequency domain involves synthesis of signals with specific time-frequency signature. In this work we observe that watermarking of time-frequency distributions is a similar problem. The proposed domain is the joint time-frequency cells of the Wigner Distributi...

We propose a signal based joint time-frequency segmentation algorithm as an extension to Herley et al. (IEEE Trans. Image Processing, 1997). Our algorithm provides an unconstrained multiresolution analysis in time and frequency adapted to the characteristics of the signal, where the time-frequency segmentation of Herley et al. is modified to achieve a minimum entropy criterion. Experimental res...

This paper deals with the analysis of temporal dependence in multivariate time series. The dependence structure between the marginal series is modelled through the use of copulas which, unlike the correlation matrix, give a complete description of the joint distribution. The parameters of the copula function vary through time following certain evolution equations depending on their previous val...

Providing suitable analgesia following diagnostic and therapeutic arthroscopic surgeries, that areconsidered to cause some degree of postoperative pain, is a necessity in equine practice. The aim of thepresent study was to evaluate the equine synovial fluid biochemical and cytological changes as well asclinical assessments of the joint following intra-articular administration of ketamine. Six a...