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Manufacturing has changed markedly in recent years. The trend is for saving on the cost of production because of market pressure. In order to achieve this goal, greater consideration has been given to automation in manufacturing. In this regard, a fundamental step is to know the condition of the cutting tool, which requires a reliable system to monitor the condition of the tool. Experimental investigation of cutting tool wear and a model for tool wear estimation is reported in the current paper. The changes in the values of cutting forces, vibrations, and acoustic emissions with cutting tool wear are recorded and analysed. On the basis of experimental results a model is developed for tool wear estimation in turning operations using an adaptive neuro fuzzy inference system (ANFIS). Acoustic emission (ring down count), vibrations (acceleration), and cutting forces, along with time, have been used to formulate the model. This model is capable of estimating the wear rate of the cutting tool. The wear estimation results obtained by the model are compared with the practical results and are presented. The model performed quite satisfactorily and gave good results with the actual and predicted tool wear values.

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This review summarizes the biological response of dentin-pulp complexes to a variety of stimuli and responses to current treatment therapies and reviews the role of tissue engineering and its application in regenerative endodontics. An electronic search was undertaken based on keywords using Medline/PubMed, Embase, Web of Science and Ovid database resources up to March 2012 to identify appropriate articles, supplemented by a manual search using reference lists from relevant articles. Inclusion criteria were mainly based on different combinations of keywords and restricted to articles published in English language only. Biological approaches based on tissue engineering principles were found to offer the possibility of restoring natural tooth vitality, with distinct evidence that regeneration of lost dental tissues is possible. Studies to formulate an ideal restorative material with regenerative properties, however, are still under way. Further research with supporting clinical studies is required to identify the most effective and safe treatment therapy.

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Titanium (Ti) and its alloys have been popularly used as implant biomaterial for decades. Recently, titanium-zirconium (TiZr) alloy has been developed as an alternative implant material with improved strength in load bearing areas. Surface modification is one of the key factors to alter the surface properties to hasten osseointegration. Spark anodic oxidation (anodization) is one such method that is reported to enhance the bone formation around implants. This study aims to anodize TiZr and study its surface characteristics and cytocompatibility by cell culture experiments using osteoblast-like cells. Titanium (Ti) and TiZr discs were anodized in an electrolyte containing DL-α-glycerophosphate and calcium acetate (CA) at 300 V. The surface characteristics were analyzed by scanning electron microscopy, electron dispersive spectroscopy, X-ray diffraction (XRD), atomic force microscopy and goniometry. Using osteoblast-like cells viability, proliferation, differentiation and mineralization was assessed. The anodized surfaces demonstrated increased oxygen, entrapped calcium and phosphorous from the electrolyte used. XRD analysis confirmed the presence of anatase in the oxide layer. Average roughness increased and there was a significant decrease in contact angle (P < 0.01) following anodization. The anodized TiZr (aTiZr) surfaces were more nano-porous compared to anodized Ti (aTi). No significant difference was found in the viability of cells, but after 24 h the total number of cells was significantly higher (P < 0.01). Proliferation, alkaline phosphatase activity and calcium deposits were significantly higher on anodized surfaces compared to machined surfaces (P < 0.05, ANOVA). Anodization of TiZr resulted in a more nanoporous and hydrophilic surface than aTi, and osteoblast biocompatibility appeared comparable to aTi.

This study presents the design of high-speed inter-building connectivity in medical services by free-space optical (FSO) link with wireless backup, which will operate at gigabit rates. The two buildings in medical campus are 500 m apart. The FSO link normally uses 1550 nm wavelength but has a radio frequency (RF) link operating at 2.4 GHz as the back-up. In this, 99.999% availability is achieved by combining the optical laser beam with an alternate path RF solution. The laser beam of 1550 nm provides high-bandwidth connectivity in majority of the time, whereas the RF path maintains critical network connectivity during extreme weather events that are detrimental to the FSO link, such as thick fog. Optical wireless links suffer from atmospheric loss mainly because of fog, scintillation and precipitation. The authors investigate here the impact of fog, rain and snow effects and evaluate their performances for the optical propagation through the atmosphere. The wireless back-up link is used only in very dense fog conditions. Hybrid FSO/RF systems have also been examined as a means to provide high-bandwidth point-to-point links in the access network over larger distances.