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991.
Synthesis,Culture Medium Stability,and In Vitro and In Vivo Zebrafish Embryo Toxicity of Metal–Organic Framework Nanoparticles 下载免费PDF全文
Dr. Arnau Carné‐Sánchez Dr. Nerea Roher Dr. Julia Lorenzo Dr. Inhar Imaz Prof. Dr. Daniel Maspoch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2508-2518
Metal–organic frameworks (MOFs) are among the most attractive porous materials available today. They have garnered much attention for their potential utility in many different areas such as gas storage, separation, catalysis, and biomedicine. However, very little is known about the possible health or environmental risks of these materials. Here, the results of toxicity studies on sixteen representative uncoated MOF nanoparticles (nanoMOFs), which were assessed for cytotoxicity to HepG2 and MCF7 cells in vitro, and for toxicity to zebrafish embryos in vivo, are reported. Interestingly, there is a strong correlation between their in vitro toxicity and their in vivo toxicity. NanoMOFs were ranked according to their respective in vivo toxicity (in terms of the amount and severity of phenotypic changes observed in the treated zebrafish embryos), which varied widely. Altogether these results show different levels of toxicity of these materials; however, leaching of solubilized metal ions plays a main role. 相似文献
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Carlo Sau Paolo Meloni Luigi Raffo Francesca Palumbo Endri Bezati Simone Casale-Brunet Marco Mattavelli 《Journal of Signal Processing Systems》2016,85(1):143-165
The implementation of processing platforms supporting multiple applications by runtime reconfigurations on dedicated hardware modules requires the solution of different problems. These problems are notably not-trivial since both platform and application complexities increase year after year. As a consequence, the design process is both time and resource demanding. System configuration along with resources management and mapping remain one of the most challenging problem, particularly when runtime adaptation is required. In this direction, the ISO/IEC SC29WG11 committee (MPEG) has developed the so called MPEG-RVC standards ISO/IEC 23001-4 and 23002-4. This standard provides specifications of video codecs in the form of dataflow programs. In this paper, an integrated design flow to derive optimized multi-functional platforms directly from disjoined high-level specifications is presented. To the authors’ best of knowledge, such an optimization, synthesis and mapping methodology for coarse-grained reconfigurable systems design does not exist within the MPEG-RVC framework. The design flow presented in this paper leverages on an integrated set of independently designed tools, all supporting the RVC standard. Results assessment has been carried out on three different scenarios: an MPEG-RVC decoder, a standard baseline MPEG-RVC JPEG codec and a generalized reconfigurable multi-quality JPEG encoder. For all these scenarios, the proposed design flow has been targeted for a Xilinx Virtex 5 FPGA. Results show how this approach is capable of yielding a reconfigurable design that preserves the original performance of the stand alone non-reconfigurable platform providing, at the same time, considerable area savings featuring a larger set of functionalities. Moreover, platforms programmability, on the basis of the required functionality ID, is automatically handled at runtime without any designer effort. 相似文献
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Ahmed El-Rafei Tobias Engelhorn Simone Wärntges Arnd Dörfler Joachim Hornegger Georg Michelson 《Magnetic resonance imaging》2013
Most of the existing methods for diagnosing glaucoma analyze the eye with a main focus on the retina, despite the transsynaptic nature of the fiber degeneration caused by glaucoma. Thus, they ignore a significant part of the visual system represented by the visual pathway in the brain. The advances in neuroimaging, especially diffusion tensor imaging (DTI), enable the identification and characterization of white matter fibers. In this work, we propose a system based on DTI analysis of the visual pathway fibers in the optic radiation for detecting and discriminating different glaucoma entities. The optic radiation is identified semi-automatically. DTI provides information about the fiber orientation as well as a set of derived parameters describing the degree of diffusion anisotropy and diffusivity. Features for each DTI derived measure are extracted from a specified region of interest on the optic radiation. The features are grouped into three sets: Histogram, co-occurrence matrices, and Laws features. For feature selection, the features are ranked using a support vector machine classifier. The highest ranked features are used for classification. A support vector machine classifier is used for classification in a 10-fold cross validation setup. The system is applied to three age-matched subjects’ categories containing 27 healthy, 39 primary open angle glaucoma (POAG), and 18 normal tension glaucoma (NTG) subjects. The discrimination accuracy between healthy and glaucoma (POAG and NTG) subjects is 94.1% with an area under the ROC of 0.97. Classification accuracy of 92.4% is obtained for the normal and the POAG groups while it increased to 100% in case of healthy and NTG groups. In addition, the system could differentiate between glaucoma types (POAG and NTG) with an accuracy of 98.3%. A complementary analysis was performed to estimate the selection bias in the obtained accuracy. The bias ranged from 10% to 20% depending on the group pair under consideration. The classification results indicate the high performance of the system compared to retina-based glaucoma detection systems. The proposed approach utilizes visual pathway analysis rather than the conventional eye analysis which presents a new trend in glaucoma detection. Analyzing the entire visual system could provide significant information that can improve the glaucoma examination flow and treatment. 相似文献
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In a recent work, Bodineau and Derrida analyzed the phase fluctuations in the ABC model. In particular, they computed the asymptotic variance and, on the basis of numerical simulations, they conjectured the presence of a drift, which they guessed to be an antisymmetric function of the three densities. By assuming the validity of the fluctuating hydrodynamic approximation, we prove the presence of such a drift, providing an analytical expression for it. This expression is then shown to be an antisymmetric function of the three densities. The antisymmetry of the drift can also be inferred from a symmetry property of the underlying microscopic dynamics. 相似文献
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