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Monocytes or macrophages from important accessory cells in the regulation of bone metabolism and destruction. Cells of the mononuclear phagocyte lineage form the precursor cells of the osteoclasts. Soluble products produced by activated macrophages regulate progenitor cell proliferation, recruitment, differentiation, and activity of osteoblasts and osteoclasts. After osteoclasts are removed from the resorption site, macrophages process bone surfaces and create a cement line before osteoblasts enter to form new bone. Although osteolysis associated with normal bone remodeling is seen as an osteoclast driven process, it may be that in chronic inflammation macrophage activation and vascular derangements lead to low pH, local bone demineralization (acid attack), and H+ mediated stimulation of the primary afferent nociceptive nerve fibers (bone pain). Osteoclasts are not able to attach to demineralized bone or to osteoid surfaces. However, if macrophages degrade the demineralized organic bone matrix, chemotactic factors and attachment sites for osteoclasts are produced. In such a scenario, the osteoclast-osteoblast mediated activation, resorption, and formation cycle would be secondarily activated. Such events may play a role in the most common orthopaedic problem related to macrophage activation, aseptic loosening of orthopaedic joint implants, which is secondary to a chronic foreign body reaction and to micromovement.  相似文献   
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Related problems of scaled matching and indexing, which aim to determine all positions in a text T that a pattern P occurs in its scaled form, are considered important because of their applications to computer vision. However, previous results only focus on enlarged patterns, and do not allow shrunk patterns since they may disappear. In this paper, we give the definition and an efficient indexing algorithm for proportionally-scaled patterns that can be visually enlarged or shrunk. The proposed indexing algorithm takes O(|T|) time in its preprocessing phase, and achieves time in its answering phase, where |T|, |P|, Up, and m denote the length of T, the length of P, the number of reported positions, and the length of T under run-length representation, respectively.  相似文献   
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This paper proposes robust refinement methods to improve the popular patch multi-view 3D reconstruction algorithm by Furukawa and Ponce (2008). Specifically, a new method is proposed to improve the robustness by removing outliers based on a filtering approach. In addition, this work also proposes a method to divide the 3D points in to several buckets for applying the sparse bundle adjustment algorithm (SBA) individually, removing the outliers and finally merging them. The residuals are used to filter potential outliers to reduce the re-projection error used as the performance evaluation of refinement. In our experiments, the original mean re-projection error is about 47.6. After applying the proposed methods, the mean error is reduced to 2.13.  相似文献   
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In this paper, we introduce a new diffusion algorithm that can be used for reducing aliasing on both step edges and lines. It derives from the diffusion model of Perona and Malik, and works as an adaptive level-curve method in which diffusion is carried out in the normal direction of the gradient for step edges, while the eigenvalues of the Hessian matrix are used for lines. To get sharp images, we use high-pass filters to preserve as much as possible the high frequency content while diffusing. Experimental tests using grayscale and colour images show that our algorithm efficiently reduces aliasing.  相似文献   
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The sorption and deposition of technetium species formed from TcO 4 at gold and platinized surfaces was followed by a coupledin situ radiometric and electrochemical technique. It was found: (i) that a layer of TcO2 species is formed preceding the massive deposition of technetium species, and (ii) that the deposition process is not connected with hydrogen evolution or reaction with adsorbed hydrogen as has been assumed in the literature. An important new finding, the electrocatalytic reduction of ClO4 ions at surfaces covered by technetium species, was demonstrated on the basis of a comparative study of the phenomena observed in H2SO4 and HClO4 supporting electrolytes.This paper is dedicated to Professor Brian E. Conway on the occasion of his 65th birthday, and in recognition of his outstanding contribution to electrochemisty.  相似文献   
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This paper presents a review on the performance of Savonius wind turbines. This type of turbine is unusual and its application for obtaining useful energy from air stream is an alternative to the use of conventional wind turbines. Simple construction, high start up and full operation moment, wind acceptance from any direction, low noise and angular velocity in operation, reducing wear on moving parts, are some advantages of using this type of machine. Over the years, numerous adaptations for this device were proposed. The variety of possible configurations of the rotor is another advantage in using such machine. Each different arrangement of Savonius rotor affects its performance. Savonius rotor performance is affected by operational conditions, geometric and air flow parameters. The range of reported values for maximum averaged power coefficient includes values around 0.05–0.30 for most settings. Performance gains of up to 50% for tip speed ratio of maximum averaged power coefficient are also reported with the use of stators. Present article aims to gather relevant information about Savonius turbines, bringing a discussion about their performance. It is intended to provide useful knowledge for future studies.  相似文献   
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