Calcium phosphate ceramic materials are extensively used for bone replacement and regeneration in orthopedic, dental, and maxillofacial surgical applications. In order for these biomaterials to work effectively it is imperative that they undergo the process of degradation and resorption in vivo. This allows for the space to be created for the new bone tissue to form and infiltrate within the implanted graft material. Several factors affect the biodegradation and resorption of calcium phosphate materials after implantation. Various cell types are involved in the degradation process by phagocytic mechanisms (monocytes/macrophages, fibroblasts, osteoblasts) or via an acidic mechanism to reduce the micro-environmental pH which results in demineralization of the cement matrix and resorption via osteoclasts. These cells exert their degradation effects directly or indirectly through the cytokine growth factor secretion and their sensitivity and response to these biomolecules. This article discusses the mechanisms of calcium phosphate material degradation in vivo.

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In wireless sensor networks with dynamic clustering, the cluster heads are usually not selected on the basis of their locations. This causes irregular distribution of cluster heads and highly variable number of nodes in the clusters. Also, some of the clusters are spread over large areas within the network, causing limited spatial correlation between associated sensor nodes. These irregularities in cluster placements and dimensions negatively impact the efficiency of a wireless sensor network. For example, for a cooperative data aggregation, it necessitates variable or large sized packets while the aggregations, based on spatial correlation of sensor nodes, cannot be exploited easily. In this paper, we have developed a Distributed Uniform Clustering Algorithm (DUCA) for cluster based WSN. In DUCA, cluster formation mechanism is based on a virtual-grid system and sensing ranges of nodes that provide even distribution of clusters, homogenized cluster sizes, and reduced energy consumption. Simulation results show that DUCA improves the distribution of cluster heads by more than 2 times and reduces the energy consumption within a range of 15% to 50% as compared to the existing protocols.

Tooth wear is a process that is usually a result of tooth to tooth and/or tooth and restoration contact. The process of wear essentially becomes accelerated by the introduction of restorations inside the oral cavity, especially in case of opposing ceramic restorations. The newest materials have vastly contributed toward the interest in esthetic dental restorations and have been extensively studied in laboratories. However, despite the recent technological advancements, there has not been a valid in vivo method of evaluation involving clinical wear caused due to ceramics upon restored teeth and natural dentition. The aim of this paper is to review the latest advancements in all-ceramic materials, and their effect on the wear of opposing dentition. The descriptive review has been written after a thorough MEDLINE/PubMed search by the authors. It is imperative that clinicians are aware of recent advancements and that they should always consider the type of ceramic restorative materials used to maintain a stable occlusal relation. The ceramic restorations should be adequately finished and polished after the chair-side adjustment process of occlusal surfaces.

Automotive multiplexing allows sharing information among various intelligent modules inside an automotive electronic system. In order to achieve an optimum functionality, the information should be exchanged among various electronic modules in real time. Data-reduction techniques are used to send the data over a transmission medium at a high speed. They can be employed in automotive multiplexing systems to improve the information exchange rate among various intelligent modules. Some off-the-shelf data-reduction algorithms have been considered for automotive multiplexing. However, their applications have been limited to text data classes only. This paper introduces a data-reduction algorithm that can be applied to all data classes found in automotive multiplexing, including body-and engine-related data. Detailed performance analysis of the algorithm is presented in this paper. Although this algorithm has been developed to fit in the automotive environment, it can also be applied to nonautomotive applications in which extensive information exchange is performed among control modules via a multiplexing bus. The proposed algorithm uses SAE J1939 as a base protocol. However, it can be used with other automotive multiplexing protocols without loss of generality.