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51.
Calabuig A Garcia J Ferreira C Zalevsky Z Micó V 《Journal of the Optical Society of America. A, Optics, image science, and vision》2011,28(11):2346-2358
Single-exposure superresolved interferometric microscopy (SESRIM) by RGB multiplexing has recently been proposed as a way to achieve one-dimensional superresolved imaging in digital holographic microscopy by a single-color CCD snapshot [Opt. Lett. 36, 885 (2011)]. Here we provide the mathematical basis for the operating principle of SESRIM, while we also present a different experimental configuration where the color CCD camera is replaced by a monochrome (B&W) CCD camera. To maintain the single-exposure working principle, the object field of view (FOV) is restricted and the holographic recording is based on image-plane wavelength-dispersion spatial multiplexing to separately record the three bandpass images. Moreover, a two-dimensional extension is presented by considering two options: time multiplexing and selective angular multiplexing. And as an additional implementation, the FOV restriction is eliminated by varying the angle between the three reference beams in the interferometric recording. Experimental results are reported for all of the above-mentioned cases. 相似文献
52.
Shiyang Lu Jian Zhang Zhiyong Wang David Dagan Feng 《Journal of Visual Communication and Image Representation》2013,24(2):127-136
Sparse coding which encodes the natural visual signal into a sparse space for visual codebook generation and feature quantization, has been successfully utilized for many image classification applications. However, it has been seldom explored for many video analysis tasks. In particular, the increased complexity in characterizing the visual patterns of diverse human actions with both the spatial and temporal variations imposes more challenges to the conventional sparse coding scheme. In this paper, we propose an enhanced sparse coding scheme through learning discriminative dictionary and optimizing the local pooling strategy. Localizing when and where a specific action happens in realistic videos is another challenging task. By utilizing the sparse coding based representations of human actions, this paper further presents a novel coarse-to-fine framework to localize the Volumes of Interest (VOIs) for the actions. Firstly, local visual features are transformed into the sparse signal domain through our enhanced sparse coding scheme. Secondly, in order to avoid exhaustive scan of entire videos for the VOI localization, we extend the Spatial Pyramid Matching into temporal domain, namely Spatial Temporal Pyramid Matching, to obtain the VOI candidates. Finally, a multi-level branch-and-bound approach is developed to refine the VOI candidates. The proposed framework is also able to avoid prohibitive computations in local similarity matching (e.g., nearest neighbors voting). Experimental results on both two popular benchmark datasets (KTH and YouTube UCF) and the widely used localization dataset (MSR) demonstrate that our approach reduces computational cost significantly while maintaining comparable classification accuracy to that of the state-of-the-art methods. 相似文献
53.
54.
Maysa Teixeira Resende Salvatore Campisi-Pinto Charles Linder Zeev Wiesman 《Journal of the American Oil Chemists' Society》2019,96(2):125-135
Polyunsaturated fatty acids (PUFA) are components of many commercial products such as edible oils, foods, cosmetics, medication, and in biological systems such as phospholipids of cellular membranes. Although PUFA aggregates are important functional components, they are also related to system degradation, because PUFA are susceptible to oxidation via their multiple double bonds and allylic carbons. Current technologies are not effective in characterizing the morphological and chemical structural domains of saturated, monounsaturated fatty acids (MUFA) and PUFA materials, or how the morphological structures of fatty acids, at the mesomolecular, nanomolecular, and molecular levels, affect their oxidation mechanisms. In this article, the 1H low-field (LF) NMR energy relaxation time technology is proposed as a tool to analyze PUFA oils undergoing thermal oxidation. This technology generates two-dimensional (2D) chemical and morphological spectra using a primal-dual interior method for the convex objectives (PDCO) optimization solver for computational processing of the energy relaxation time signals T1 (spin–lattice) and T2 (spin–spin). The 2D graphical maps of T1 vs. T2 generated for butter, rapeseed oil, soybean oil, and linseed oil show that the different degrees of unsaturation of fatty-acid oils affect their chemical and morphological domains, which influences their oxidative propensity. The technology of the 1H LF-NMR energy relaxation time proved to be an effective tool to characterize and monitor PUFA oxidation. 相似文献
55.
Corpus-based automatic thesaurus construction uses linguistic methods, such as Part-of-Speech taggers and parsers, which often perform poorly on MRLs. Therefore, in this paper, we focused on the complex task of adapting corpus-based thesaurus construction methods for MRLs. We investigated two statistical approaches for thesaurus construction; a) a first-order co-occurrence-based approach and b) a second-order distributional-based approach. We explored alternative levels of morphological term representations complemented by grouping the morphological variants. We then introduced and adopted a generic algorithmic scheme for thesaurus construction in MRLs for both first-order and second-order approaches. Our scheme investigated alternative representation levels and offered alternative configurations. We demonstrated the empirical benefits of our methodology for a diachronic Hebrew thesaurus construction. We used morphological analysis tools, defined and applied a new annotation scheme, and demonstrated its optimal configuration, which outperforms the baseline for both first and second order corpus-based thesaurus construction approaches. 相似文献
56.
Biomedical function imaging and tracer kinetic modeling with Positron Emission Tomography (PET) are based on continuous data acquisition and time accumulated counts measurements. In dynamic cardiac studies, both the model input and output measurements are obtained simultaneously from the same sequence of PET images. In this paper, techniques in general PET optimal sampling schedule design for tracer kinetic modeling, based on continuous data acquisition and time accumulated counts measurements, are introduced. A special case in which simultaneous optimal sampling schedule design is required for both input and output measurements is also introduced. 相似文献
57.
Monoclonal antibodies of human origin may have great therapeutic value in the treatment of cancer, autoimmune disorders and viral or bacterial infections. Several methods for generating human monoclonal antibodies exist; some are based on the transplantation of a functioning human immune system into severe combined immunodeficient (scid) mice or into Trimera mice, which are mice that have been lethally irradiated and radioprotected by transplantation of bone-marrow cells from scid mice. Trimera mice could be also used to develop animal models for human diseases by transplanting infected human tissue fragments and for creating models for cell therapy. 相似文献
58.
Jaspal S. Bola Henna Popli Ryan M. Stolley Haoliang Liu Hans Malissa Ohyun Kwon Christoph Boehme Joel S. Miller Zeev Valy Vardeny 《Advanced functional materials》2021,31(30):2100687
Organic-based magnetic materials have been used for spintronic device applications as electrodes of spin aligned carriers and spin-pumping substrates. Their advantages over more traditional inorganic magnets include reduced magnetic damping and lower fabrication costs. Vanadium tetracyanoethylene, V[TCNE]x (x ≈ 2), is an organic-based ferrimagnet with an above room-temperature magnetic order temperature (Tc ≈ 400 K). V[TCNE]x has deposition flexibility and can be grown on a variety of substrates via low-temperature chemical vapor deposition (CVD). A systematic study of V[TCNE]x thin-film CVD parameters to achieve optimal film quality, reproducibility, and excellent magnetic properties is reported. This is assessed by broadband ferromagnetic resonance (FMR) that shows most narrow linewidth of ≈1.5 Gauss and an extremely low Gilbert damping coefficient. The neat V[TCNE]x films are shown to be efficient spin injectors via spin pumping into an adjacent platinum layer. Also, under an optimized FMR linewidth, the V[TCNE]x films exhibit Fano-type resonance with a continuum broadband absorption in the microwave range, which can be readily tuned by the microwave frequency. 相似文献
59.
Switching Futile para‐Quinone to Efficient Reactive Oxygen Species Generator: Ubiquitin‐Specific Protease‐2 Inhibition,Electrocatalysis, and Quantification
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Dr. Pushparathinam Gopinath Dr. Atif Mahammed Tal Eilon‐Shaffer Mickal Nawatha Shimrit Ohayon Prof. Doron Shabat Prof. Zeev Gross Prof. Ashraf Brik 《Chembiochem : a European journal of chemical biology》2017,18(17):1683-1687
Understanding the correlation between structural features of small‐molecule drugs and their mode of action is a fascinating topic and crucial for the drug‐discovery process. However, in many cases, knowledge of the exact parameters that dictate the mode of action is still lacking. Following a large screening for ubiquitin specific protease 2 (USP2) inhibition, an effective para‐quinone‐based inhibitor with an unclear mode of action was identified. To gain a deeper understanding of the mechanism of inhibition, a set of para‐quinones were prepared and studied for USP2 inhibition, electrocatalysis, and reactive oxygen species (ROS) quantification. The excellent correlation obtained from the above‐mentioned studies disclosed a distinct pattern of “N?C=O?N” in the bicyclic para‐quinones to be a crucial factor for ROS generation, and demonstrated that minor changes in such a skeleton drastically altered the ROS‐generating ability. The knowledge acquired herein would serve as an important guideline for future medicinal chemistry optimization of related structures to select the preferred mode of action. 相似文献
60.
Cover Picture: Switching Futile para‐Quinone to Efficient Reactive Oxygen Species Generator: Ubiquitin‐Specific Protease‐2 Inhibition,Electrocatalysis, and Quantification (ChemBioChem 17/2017)
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