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Point-cloud-based techniques play a very significant role in the archaeological application for stone tools. Measured point data involve small noises, which are overlaps obtained through measurement by laser devices. Such noisy data make it difficult to extract highly accurate segmented flakes, which will be used for the refitted flake matching process, because potential feature points lying on the boundary edges are hardly extracted. To overcome this issue, this paper describes a method of recognizing flake surfaces with noisy point clouds. First, the resampling method is applied to remove the noise in the input data. Then, the surface variation is calculated with a various number of neighbors and the potential feature points are detected by analyzing its surface variation. After that, feature lines are extracted from the potential feature points. The feature lines represent boundary edges of the flake surfaces. Finally, flake surfaces are extracted by the feature-line-based segmentation method. The implementation of this work can recognize flake surfaces from noisy data.

A rotational/linear two degrees-of-freedom switched reluctance motor (2DOF-SRM) has been developed for the purpose of independent control of rotational and linear actuations on one actuator. In the previous study, noncontact-type angular and linear position sensing system that used photoelectric sensors was developed. It was successfully applied to the independent rotational speed and linear displacement control of the 2DOF-SRM. In this paper, both the torque and thrust control are developed as the new function of the 2DOF-SRM. This control is achieved by the electric current control for each phase windings. In this system, actual torque and thrust are independently estimated by a simplified matrix expression from the information of the phase winding current. The performance test results for torque and thrust estimation are presented.

Welded structures which set up in outdoor in snow-and cold-prone areas are exposed to severe environment, in which liquids containing Cl-chloride ions from the sea breeze and snow melting agents undergo freeze-thaw cycles during the winter. Cl-solutions are known to produce pitting corrosion in austenitic stainless steel. However, the relationship between the freeze-thaw environment and pitting corrosion occurred in welded austenitic stainless steel has not yet been clarified. In the present study, the effect of the freeze-thaw environment on pitting corrosion in welded austenitic stainless steel submersed in Cl-solutions is investigated. AISI 304 (X5CrNi18-10 in ISO/TS 15510, SUS304 in JIS G 4305) samples with bead-on-plate welding are used as specimens. The thickness of the specimen is 4 mm. The specimens are fully immersed in FeCl3 solution. The freeze-thaw environment is created by temperature cycling from 20°C to-20°C. In the meanwhile, residual stresses due to the welding process in stainless steel structures can significantly affect behavior of pitting corrosion as same as influence of sensitization. Authors carried out the welding simulation as the purpose of predicting the welding-heat history and residual stress near the welding bead. As a result, large-scale pitting corrosion occurs primarily in areas of high tensile residual stress and sensitive metallographic structures near weld beads in the freeze-thaw environment. Accelerated pitting corrosion is confirmed to have occurred as a result of concentration cell corrosion due to the local concentration of Cl-chlorine ion around a weld bead during freezing and thawing of the solution. Furthermore, based on your study it became clear that the center position of large-scale pitting corrosion is in agreement with the simulation result rather than the stress peak position by X rays measurement.

Background The purpose of this study was to use functional magnetic resonance imaging (fMRI) to quantify changes in brain activity during experimental occlusal interference. Methods Fourteen healthy volunteers performed a rhythmical tapping occlusion task with experimental occlusal interference of the right molar tooth at 0 mm (no occlusion), 0.5 mm, and 0.75 mm. The blood-oxygen-level dependent (BOLD) signal was quantified using statistical parametric mapping and compared between rest periods and task periods. Results In tapping tasks with experimental occlusal interference of 0.75 mm or 0.5 mm, there was clear activation of the contralateral teeth-related primary sensory cortex and Brodmann’s area 46. At 0 and 30 minutes after removal of the experimental occlusal interference, the activation clearly appeared in the bilateral teeth-related primary sensory cortices and Brodmann’s area 46. At 60 minutes after the removal of the experimental occlusal interference, the activation of Brodmann’s area 46 had disappeared, and only the bilateral teeth-related primary sensory cortices were active. Conclusions The present results suggest that adjustments for experimental occlusal interference can be objectively evaluated using fMRI. We expect that this method of evaluating adjustments in occlusal interference, combined with fMRI and the tapping task, could be applied clinically in the future.

Thirty one patients with internal derangement of the TMJ and 12 subjects with normal TMJ were selected and their MR imaging and border movements of the mandible were recorded. Inaddition, the relationship between them was examined.In this study, the disk position and configuration in MR findings were classified as follows. Diskposition: superior, anterior and anterolateral (medial and lateral were omitted), grade of anteriordisk displacement (with and without reduction): slight, moderate and severe, disk configuration: biconcave, enlargement of posterior band, even thickness and biconvex.The results were as follows:1. Border movements of the mandible were influenced not only by unilateral or bilateralinternal derangement but also by with or without reduction of the disk.2. Border movements in patients with anterolateral disk displacement were more severelyrestricted than those with anterior disk displacement.3. Border movements were remarkably limited in patients with slight disk displacement, especially in unilateral cases with reduction of the disk.4. Border movements in patients with even thickness and biconvex types of disk configurationwere a little restricted and rather similar to those of normal subjects.5. There was significant correlation between border movements and disk position and configu-ration. It means that measurement of the mandibular movements is very significant to diagnose thecondition of internal derangements of the TMJ.

Endothelial cells in the atrioventricular (AV) segment of the developing chicken heart undergo a transition into mesenchymal cells. When the AV segment is explanted onto a hydrated collagen gel, endothelial cells grow out and reproduce in vivo cell transition regardless of the precise orientation of the explant on a gel. Our results showed that when the luminal side of an explant was placed towards a gel surface, the inverted polarity of endothelium was not adjusted by direct reorganization of polarity, but that the endothelium crawled down so as to settle on a gel surface in the correct original cell polarity. Subsequently, endothelial cells showed cytoplasmic hypertrophy, formed microvillous projections and then extended filopodial migratory appendages. These cellular changes were quite similar to those in vivo. However, the continuity of the endothelial layer was specifically disrupted in AV explant cultures. Such disruption was never observed in ventricle explant cultures in which endothelial-mesenchymal cell transition did not occur. The disintegration of AV endothelial outgrowth must be closely related to its capability to transform into mesenchymal cells and mitotic activity to keep a depository of endothelial cells.

Hard- and soft-X-ray photoelectron spectroscopies (HAXPES and SXPES) are very powerful for studying the bulk electronic structures of strongly correlated electron systems. The presence of an intrinsic surface layer on clean fractured surfaces is demonstrated for LiV 2 O 4 . In this material, single-nucleus recoil effects are very prominent not only for all core levels but also for valence states at 20 K. However, such recoil effects are negligible in VO 2 even at 350 K in spite of the fact that VO 2 has a similar V–O 6 octahedron structure. The marked intensity increase in the high-binding-energy part of the so-called O 2p band relative to the V 3d band in HAXPES is interpreted to be due to the V 4s state contribution. Very high resolution extremely low energy photoelectron spectroscopy (ELEPES) is performed with Kr and Xe lamps at 10.1 and 8.4 eV, respectively, demonstrating its bulk sensitivity for this material with heavy-Fermion-like behavior.

The outermost surface cell layer of the developing embryo, the periderm, arises from the initial single layer of ectoderm and is eventually exfoliated from the stratified epidermis, which has the same ectodermal origin. In this study, monoclonal antibodies against chicken limb bud ectoderm were generated and screened for those which stained the periderm. Four separate antibodies termed PD2, 3, 7 and 9 were obtained from 180 mixed hybridomas. These PD antibodies stained the periderm selectively at all stages examined (stage 20-42). By correlating the results of immunohistochemistry with observations made by transmission electron microscopy, it was revealed that PD antibodies stained both the squamous periderm at an early stage and rounded bulging peridermal cells just before exfoliation. Therefore we feel that PD antibodies may be useful in further systematic investigations of the development and function of the chicken embryonic periderm.