Objective The structure-function relationship in the healthy temporomandibular joint (TMJ) disc has been well established, however the changes in dysfunctional joints has yet to be systematically evaluated. Due to the poor understanding of the etiology of temporomandibular disorders (TMDs) this study evaluated naturally occurring degenerative remodeling in aged female porcine temporomandibular joint (TMJ) discs in order to gain insight into the progression and effects on possible treatment strategies of TMDs. Design Surface and regional biomechanical and biochemical properties of discal tissues were determined in grossly deformed (≥ Wilkes Stage 3) and morphologically normal (≤ Wilkes Stage 2) TMJ discs. Results Compared to normal disc structure the deformed discs lacked a smooth biconcave shape and characteristic ECM organization. Reduction in tensile biomechanical integrity and increased compressive stiffness and cellularity was found in deformed discs. Regionally, the posterior and intermediate zones of the disc were most frequently affected along with the inferior surface. Conclusions The frequency of degeneration observed on the inferior surface of the disc (predominantly posterior), suggests that a disruption in the disc-condyle relationship likely contributes to the progression of joint dysfunction more than the temporodiscal relationship. As such, the inferior joint space may be an important consideration in early clinical diagnosis and treatment of TMDs, as it is overlooked in techniques performed in the upper joint space, including arthroscopy and arthrocentesis. Furthermore, permanent damage to the disc mechanical properties would limit the ability to successfully reposition deformed discs, highlighting the importance of emerging therapies such as tissue engineering.

An adaptive receiver structure is considered for obtaining timing information for a direct-sequence codedivision multiple-access (CDMA) communication network operating in a near-far environment. The receiver consists of a chip matched filter followed by an LMS adaptive equalizer. By using a simple channel access protocol, the timing information for a new system user can be extracted from the weights of the adaptive equalizer. A maximum-likelihood estimation algorithm based on several simplistic assumptions on the statistical properties of the adaptive filter weights has previously been presented. In this paper, the coarse code acquisition performance of the estimation algorithm will be investigated. Based on the estimation algorithm, a union bound will be created to give an upper bound on the probability of not achieving coarse code acquisition. System DescriptionIn this paper, a standard asynchronous DS-CDMA model is assumed. The k* system user is assumed to transmit a signal of the form S k ( t ) = $ d k ( t ) c k ( t ) 'Os (l)where e,, d k ( t ) , and c k ( t ) are the phase, data sequence, and code sequence of the k* user respectively.Both the data sequence and the code sequence are assumed to be in polar form. There are a total of K system users, with user 1 assumed to be the desired user. There are a total of N code chips per data bit, where N is the number of chips in one period of a code sequence. The received signal is a composite sum of these transmitted signals each delayed by an amount z,, which is uniformly distributed over a bit interval (0, Tb) , plus additive white Gaussian noise. Note that due to the relationship between a data bit interval and one period of a code sequence, the k" user's transmission delay, zk, can be expressed as ' k = P k T c +where p k is an integer, 6, is a fraction, and Tc is a code chip interval. d f l m nTc L