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The Journal of Supercomputing - A multimedia-based medical decision-making system is an ultimate requirement in the medical imaging domain. In the healthcare sector, achieving quick and efficient...  相似文献   
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The paper addresses specific problems associated with formulating investment priorities for national road improvements in Korea. More specifically, the objectives of the paper are (1) to present a model for formulating investment priorities for road improvements that may be useful to developing countries, (2) to test the model with simplified data for deriving investment priorities for Korea's road improvements, and (3) to learn lessons that can be applicable to other developing countries with particular respect to recommending investment priorities for road improvements. The study results are useful for planners, in developing countries, and also for evaluation analysts in funding institutions who are confronted with evaluating investment priorities for deteriorating road conditions.  相似文献   
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Rubinstein-Taybi syndrome (RSTS) is a rare condition with a prevalence of 1 in 125,000–720,000 births and characterized by clinical features that include facial, dental, and limb dysmorphology and growth retardation. Most cases of RSTS occur sporadically and are caused by de novo mutations. Cytogenetic or molecular abnormalities are detected in only 55% of RSTS cases. Previous genetic studies have yielded inconsistent results due to the variety of methods used for genetic analysis. The purpose of this study was to use whole exome sequencing (WES) to evaluate the genetic causes of RSTS in a young girl presenting with an Autism phenotype. We used the Autism diagnostic observation schedule (ADOS) and Autism diagnostic interview revised (ADI-R) to confirm her diagnosis of Autism. In addition, various questionnaires were used to evaluate other psychiatric features. We used WES to analyze the DNA sequences of the patient and her parents and to search for de novo variants. The patient showed all the typical features of Autism, WES revealed a de novo frameshift mutation in CREBBP and de novo sequence variants in TNC and IGFALS genes. Mutations in the CREBBP gene have been extensively reported in RSTS patients, while potential missense mutations in TNC and IGFALS genes have not previously been associated with RSTS. The TNC and IGFALS genes are involved in central nervous system development and growth. It is possible for patients with RSTS to have additional de novo variants that could account for previously unexplained phenotypes.  相似文献   
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Flat optics, realized by the artificially created 2D material platform called optical metasurfaces, is currently undergoing a science-to-technology transition. However, “real-time” active operations of such flat optical devices remain yet unresolved. Here, liquid crystals (LCs)-integrated metaholograms for ultracompact dynamic holographic displays are proposed. The anisotropic nature of the LCs allows facile and repeatable manipulation of the polarization of light. Specifically designed (“designer”) LCs and efficient helicity-encoded metaholograms are combined to realize stimuli-responsive dynamic displays. The designer LC modulators are used as switches that enable a variety of external stimuli (e.g., electric field, heat, surface pressure) to operate holographic images in real-time. Such a dynamic metaholographic platform will provide a path to external stimuli-driven “smart” sensing and display applications such as hologram labels for temperature/pressure/touch monitoring and interactive holographic displays with haptic motion recognition.  相似文献   
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Multimedia Tools and Applications - Social networks are not new to the IT landscape. Starting from bulletin boards and chat rooms, they have evolved to include desktop and mobile device...  相似文献   
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The exponential growth in the volume of digital image databases is making it increasingly difficult to retrieve relevant information from them. Efficient retrieval systems require distinctive features extracted from visually rich contents, represented semantically in a human perception-oriented manner. This paper presents an efficient framework to model image contents as an undirected attributed relational graph, exploiting color, texture, layout, and saliency information. The proposed method encodes salient features into this rich representative model without requiring any segmentation or clustering procedures, reducing the computational complexity. In addition, an efficient graph-matching procedure implemented on specialized hardware makes it more suitable for real-time retrieval applications. The proposed framework has been tested on three publicly available datasets, and the results prove its superiority in terms of both effectiveness and efficiency in comparison with other state-of-the-art schemes.  相似文献   
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Low‐temperature anionic ring‐opening homopolymerizations and copolymerizations of two glycidol derivatives (allyl glycidyl ether (AGE) and ethoxyethyl glycidyl ether (EEGE)) are studied using a metal‐free catalyst system, 3‐phenyl‐1‐propanol (PPA) (an initiator) and 1‐tert‐butyl‐4,4,4‐tris(dimethylamino)‐2,2‐bis[tris‐(dimethylamino)phosphoranylidenamino]‐2Λ5,4Λ5‐catenadi(phosphazene) (t‐Bu‐P4) (a promoter) in order to obtain well‐defined functional linear polyethers and diblock copolymers. With the aid of the catalyst system, AGE is found to successfully undergo anionic ring‐opening polymerization (ROP) even at room temperature (low reaction temperature) without any side reactions, producing well‐defined linear AGE‐homopolymer in a unimodal narrow molecular weight distribution. Under the same conditions, EEGE also undergoes polymerization, producing a linear EEGE‐homopolymer in a unimodal narrow molecular‐weight distribution. In this case, however, a side reaction (i.e., chain‐transfer reaction) is found to occur at low levels during the early stages of polymerization. The chemical properties of the monomers in the context of the homopolymerization reactions are considered in the design of a protocol used to synthesize well‐defined linear diblock copolyethers with a variety of compositions. The approach, anionic polymerization via the sequential step feed of AGE and EEGE as the first and second monomers, is found to be free from side reactions at room temperature. Each block of the obtained linear diblock copolymers undergoes selective deprotection to permit further chemical modification for selective functionalization. In addition, thermal properties and structures of the polymers and their post‐modification products are examined. Overall, this study demonstrates that a low‐temperature metal‐free anionic ROP using the PPA/t‐Bu‐P4 catalyst system is suitable for the production of well‐defined linear AGE‐homopolymers and their diblock copolymers with the EEGE monomer, which are versatile and selectively functionalizable linear aliphatic polyether platforms for a variety of post‐modifications, nanostructures, and their applications.  相似文献   
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