9,717 research outputs found

    Investigation of the SH3BP2 Gene Mutation in Cherubism

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    Cherubism is a rare developmental lesion of the jaw that is generally inherited as an autosomal dominant trait. Recent studies have revealed point mutations in the SH3BP2 gene in cherubism patients. In this study, we examined a 6-year-old Korean boy and his family. We found a Pro418Arg mutation in the SH3BP2 gene of the patient and his mother. A father and his 30-month-old younger brother had no mutations. Immunohistochemically, the multinucleated giant cells proved positive for CD68 and tartrate-resistant acid phosphatase (TRAP). Numerous spindle-shaped stromal cells expressed a ligand for receptor activator of nuclear factor kB (RANKL), but not in multinucleated giant cells. These results provide evidence that RANKL plays a critical role in the differentiation of osteoclast precursor cells to multinucleated giant cells in cherubism. Additionally, genetic analysis may be a useful method for differentiation of cherubism.</p

    Chiral rings and GSO projection in Orbifolds

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    The GSO projection in the twisted sector of orbifold background is sometimes subtle and incompatible descriptions are found in literatures. Here, from the equivalence of partition functions in NSR and GS formalisms, we give a simple rule of GSO projection for the chiral rings of string theory in \C^r/\Z_n, r=1,2,3r=1,2,3. Necessary constructions of chiral rings are given by explicit mode analysis.Comment: 24 page

    The Effects of Carry-on Baggage on Aircraft Evacuation Efficiency

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    The most frequent obstacle of an aircraft evacuation is the passengers carrying baggage while evacuating. Passengers who insist on taking their carry-on baggage during an emergency evacuation not only slow down the evacuation process but also act as a significant risk to the safety of other passengers. This study investigated the factors that affect passengersā€™ behavioral intention to evacuate with carry-on baggage and the effects of evacuating with carry-on baggage on the total evacuation time. Overall, two studies were conducted to provide an outline of the factors that affect and affected by carry-on baggage. Study 1 used an agent-based model, AnyLogic, to simulate the aircraft evacuation model of an A380. The model was validated, and a two-way Analysis of Variance (ANOVA) was conducted to examine the effects of the percentage of passengers evacuating with carry-on baggage and exit selection choices on the total evacuation time. The simulation results suggested that the mean evacuation time for 0% was significantly lower than 50% and 80%. The mean evacuation time for the shortest queue choice was also lower than the closest exit choice. Study 2 used an expanded theory of planned behavior (TPB) to determine the factors that affect passengersā€™ intentions to evacuate with carry-on baggage. The total sample size was 281 after data cleaning. The confirmatory factor analysis (CFA) and structural equation model (SEM) were used to analyze the data. The results indicated that attitude was the significant determinant of passengersā€™ intention to evacuate with carryon baggage. The factor of ā€˜perceived riskā€™ was not supported, but the results showed that the opposite effect of the hypothesis was significant. The results of this study fill a gap in the research regarding passengersā€™ behavior of evacuating with carry-on baggage. Potential applications of this study will also help the federal regulations, airlines, and aircraft manufacturers by providing a better understanding of carry-on baggage at aircraft emergency

    Detection of Core-Periphery Structure in Networks Using Spectral Methods and Geodesic Paths

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    We introduce several novel and computationally efficient methods for detecting "core--periphery structure" in networks. Core--periphery structure is a type of mesoscale structure that includes densely-connected core vertices and sparsely-connected peripheral vertices. Core vertices tend to be well-connected both among themselves and to peripheral vertices, which tend not to be well-connected to other vertices. Our first method, which is based on transportation in networks, aggregates information from many geodesic paths in a network and yields a score for each vertex that reflects the likelihood that a vertex is a core vertex. Our second method is based on a low-rank approximation of a network's adjacency matrix, which can often be expressed as a tensor-product matrix. Our third approach uses the bottom eigenvector of the random-walk Laplacian to infer a coreness score and a classification into core and peripheral vertices. We also design an objective function to (1) help classify vertices into core or peripheral vertices and (2) provide a goodness-of-fit criterion for classifications into core versus peripheral vertices. To examine the performance of our methods, we apply our algorithms to both synthetically-generated networks and a variety of networks constructed from real-world data sets.Comment: This article is part of EJAM's December 2016 special issue on "Network Analysis and Modelling" (available at https://www.cambridge.org/core/journals/european-journal-of-applied-mathematics/issue/journal-ejm-volume-27-issue-6/D245C89CABF55DBF573BB412F7651ADB

    Tau functions as Widom constants

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    We define a tau function for a generic Riemann-Hilbert problem posed on a union of non-intersecting smooth closed curves with jump matrices analytic in their neighborhood. The tau function depends on parameters of the jumps and is expressed as the Fredholm determinant of an integral operator with block integrable kernel constructed in terms of elementary parametrices. Its logarithmic derivatives with respect to parameters are given by contour integrals involving these parametrices and the solution of the Riemann-Hilbert problem. In the case of one circle, the tau function coincides with Widom's determinant arising in the asymptotics of block Toeplitz matrices. Our construction gives the Jimbo-Miwa-Ueno tau function for Riemann-Hilbert problems of isomonodromic origin (Painlev\'e VI, V, III, Garnier system, etc) and the Sato-Segal-Wilson tau function for integrable hierarchies such as Gelfand-Dickey and Drinfeld-Sokolov.Comment: 26 pages, 6 figure

    Origin of the increased velocities of domain wall motions in soft magnetic thin-film nanostripes beyond the velocity-breakdown regime

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    It is known that oscillatory domain-wall (DW) motions in soft magnetic thin-film nanostripes above the Walker critical field lead to a remarkable reduction in the average DW velocities. In a much-higher-field region beyond the velocity-breakdown regime, however, the DW velocities have been found to increase in response to a further increase of the applied field. We report on the physical origin and detailed mechanism of this unexpected behavior. We associate the mechanism with the serial dynamic processes of the nucleation of vortex-antivortex (V-AV) pairs inside the stripe or at its edges, the non-linear gyrotropic motions of Vs and AVs, and their annihilation process. The present results imply that a two-dimensional soliton model is required for adequate interpretation of DW motions in the linear- and oscillatory-DW-motion regimes as well as in the beyond-velocity-breakdown regime.Comment: 16 pages, 3 figure
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