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Proceedings Article

Image Processing

01 Jan 1994-
TL;DR: The main focus in MUCKE is on cleaning large scale Web image corpora and on proposing image representations which are closer to the human interpretation of images.
Abstract: MUCKE aims to mine a large volume of images, to structure them conceptually and to use this conceptual structuring in order to improve large-scale image retrieval. The last decade witnessed important progress concerning low-level image representations. However, there are a number problems which need to be solved in order to unleash the full potential of image mining in applications. The central problem with low-level representations is the mismatch between them and the human interpretation of image content. This problem can be instantiated, for instance, by the incapability of existing descriptors to capture spatial relationships between the concepts represented or by their incapability to convey an explanation of why two images are similar in a content-based image retrieval framework. We start by assessing existing local descriptors for image classification and by proposing to use co-occurrence matrices to better capture spatial relationships in images. The main focus in MUCKE is on cleaning large scale Web image corpora and on proposing image representations which are closer to the human interpretation of images. Consequently, we introduce methods which tackle these two problems and compare results to state of the art methods. Note: some aspects of this deliverable are withheld at this time as they are pending review. Please contact the authors for a preview.
Citations
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Journal ArticleDOI
TL;DR: This structure is the first of a glucan-bound glucan phosphatase and provides new insights into the molecular basis of this agriculturally and industrially relevant enzyme family as well as the unique mechanism of LSF2 catalysis, substrate specificity, and interaction with starch granules.
Abstract: Starch is a water-insoluble, Glc-based biopolymer that is used for energy storage and is synthesized and degraded in a diurnal manner in plant leaves. Reversible phosphorylation is the only known natural starch modification and is required for starch degradation in planta. Critical to starch energy release is the activity of glucan phosphatases; however, the structural basis of dephosphorylation by glucan phosphatases is unknown. Here, we describe the structure of the Arabidopsis thaliana starch glucan phosphatase like sex four2 (LSF2) both with and without phospho-glucan product bound at 2.3A and 1.65A, respectively. LSF2 binds maltohexaose-phosphate using an aromatic channel within an extended phosphatase active site and positions maltohexaose in a C3-specific orientation, which we show is critical for the specific glucan phosphatase activity of LSF2 toward native Arabidopsis starch. However, unlike other starch binding enzymes, LSF2 does not possess a carbohydrate binding module domain. Instead we identify two additional glucan binding sites located within the core LSF2 phosphatase domain. This structure is the first of a glucan-bound glucan phosphatase and provides new insights into the molecular basis of this agriculturally and industrially relevant enzyme family as well as the unique mechanism of LSF2 catalysis, substrate specificity, and interaction with starch granules.

33 citations

Journal ArticleDOI
TL;DR: The results are suggestive of an evolutionary mismatch, whereby a physical characteristic once tied to antisocial tendencies in ancestral environments is—in modern environments—not predictive of such behaviors but instead predictive of biased perceptions.
Abstract: This study contributes to the growing literature linking physical characteristics and behavioral tendencies by advancing the current debate on whether a person's facial width-to-height ratio (fWHR) predicts a variety of antisocial tendencies. Specifically, our large-scale study avoided the social-desirability bias found in self-reports of behavioral tendencies by capturing survey data not only from more than 1,000 business executives but also from evaluators who reported knowing the focal individuals well. With this improved research design, and after conducting a variety of analyses, we found very little evidence of fWHR predicting antisocial tendencies. In light of prior research linking fWHR to social perceptions of evaluators, our results are suggestive of an evolutionary mismatch, whereby a physical characteristic once tied to antisocial tendencies in ancestral environments is-in modern environments-not predictive of such behaviors but instead predictive of biased perceptions.

33 citations

Journal ArticleDOI
Liang Shi1, Zhenyong Wang, Xiuchao Geng1, Yuhao Zhang1, Ziqing Xue1 
10 May 2020
TL;DR: GCFs-derived exosomal miRNA-34 may be a promising targeting molecule for therapeutic strategies in GC and related mechanisms, and exosomes derived from GCFs were taken up by GC cells in vitro and in vivo and exerted antitumor roles in GC.
Abstract: Gastric cancer (GC) is one of the most common malignancies worldwide manifesting high morbidity and mortality. Cancer-associated fibroblasts (CAFs), important components of the tumor microenvironment, are essential for tumorigenesis and progression. Exosomes secreted from CAFs have been reported as the critical molecule-vehicle in intercellular crosstalk. However, the precise mechanism underlying the effect of CAFs remains to be fully investigated. In this study, we aimed to determine the role of CAFs and their exosomes in the progression of GC and related mechanisms. The results revealed that miRNA-34 was downregulated in both GC fibroblasts (GCFs) and GC cell lines while the overexpression of miRNA-34 suppressed the proliferation, invasion, and motility of GC cell lines. Coculturing GC cells with miRNA-34-overexpressing GCFs led to the suppression of cancer progression. Also, exosomes derived from GCFs were taken up by GC cells in vitro and in vivo and exerted antitumor roles in GC. In addition, exosomal miRNA-34 inhibited GC cell proliferation and invasion in vitro and suppressed tumor growth in vivo. Furthermore, 16 genes were identified as potential downstream targeting genes of miRNA-34. Taken together, GCFs-derived exosomal miRNA-34 may be a promising targeting molecule for therapeutic strategies in GC.

33 citations

Journal ArticleDOI
31 Aug 2019
TL;DR: In this paper, a filter based on the classifier's score can be trained to retain 99% of the interesting events and reduce the false-positive rate by as much as one order of magnitude for certain background processes.
Abstract: We show how event topology classification based on deep learning could be used to improve the purity of data samples selected in real time at at the Large Hadron Collider. We consider different data representations, on which different kinds of multi-class classifiers are trained. Both raw data and high-level features are utilized. In the considered examples, a filter based on the classifier's score can be trained to retain ~99% of the interesting events and reduce the false-positive rate by as much as one order of magnitude for certain background processes. By operating such a filter as part of the online event selection infrastructure of the LHC experiments, one could benefit from a more flexible and inclusive selection strategy while reducing the amount of downstream resources wasted in processing false positives. The saved resources could be translated into a reduction of the detector operation cost or into an effective increase of storage and processing capabilities, which could be reinvested to extend the physics reach of the LHC experiments.

33 citations

Journal ArticleDOI
TL;DR: A quantitative analysis of growth dynamics of the Drosophila eye primordium reveals that the area growth rate declines in inverse proportion to the increasing total area.
Abstract: The size and shape of organs is species specific, and even in species in which organ size is strongly influenced by environmental cues, such as nutrition or temperature, it follows defined rules. Therefore, mechanisms must exist to ensure a tight control of organ size within a given species, while being flexible enough to allow for the evolution of different organ sizes in different species. We combined computational modeling and quantitative measurements to analyze growth control in the Drosophila eye disc. We find that the area growth rate declines inversely proportional to the increasing total eye disc area. We identify two growth laws that are consistent with the growth data and that would explain the extraordinary robustness and evolutionary plasticity of the growth process and thus of the final adult eye size. These two growth laws correspond to very different control mechanisms and we discuss how each of these laws constrains the set of candidate biological mechanisms for growth control in the Drosophila eye disc.

33 citations


Cites methods from "Image Processing"

  • ...1B,C, yellow line) were also measured using ImageJ....

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  • ...Eye sizes of adult flies were measured using ImageJ....

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  • ...To measure the geometrical properties in 2D, maximum intensity projections were generated in ImageJ (Abràmoff et al., 2004) and the areas as well as the posterior length (Fig....

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  • ...Image processing with ImageJ....

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References
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Journal ArticleDOI
01 Nov 1973
TL;DR: These results indicate that the easily computable textural features based on gray-tone spatial dependancies probably have a general applicability for a wide variety of image-classification applications.
Abstract: Texture is one of the important characteristics used in identifying objects or regions of interest in an image, whether the image be a photomicrograph, an aerial photograph, or a satellite image. This paper describes some easily computable textural features based on gray-tone spatial dependancies, and illustrates their application in category-identification tasks of three different kinds of image data: photomicrographs of five kinds of sandstones, 1:20 000 panchromatic aerial photographs of eight land-use categories, and Earth Resources Technology Satellite (ERTS) multispecial imagery containing seven land-use categories. We use two kinds of decision rules: one for which the decision regions are convex polyhedra (a piecewise linear decision rule), and one for which the decision regions are rectangular parallelpipeds (a min-max decision rule). In each experiment the data set was divided into two parts, a training set and a test set. Test set identification accuracy is 89 percent for the photomicrographs, 82 percent for the aerial photographic imagery, and 83 percent for the satellite imagery. These results indicate that the easily computable textural features probably have a general applicability for a wide variety of image-classification applications.

20,442 citations

Book
03 Oct 1988
TL;DR: This chapter discusses two Dimensional Systems and Mathematical Preliminaries and their applications in Image Analysis and Computer Vision, as well as image reconstruction from Projections and image enhancement.
Abstract: Introduction. 1. Two Dimensional Systems and Mathematical Preliminaries. 2. Image Perception. 3. Image Sampling and Quantization. 4. Image Transforms. 5. Image Representation by Stochastic Models. 6. Image Enhancement. 7. Image Filtering and Restoration. 8. Image Analysis and Computer Vision. 9. Image Reconstruction From Projections. 10. Image Data Compression.

8,504 citations

Journal ArticleDOI
TL;DR: The image coding results, calculated from actual file sizes and images reconstructed by the decoding algorithm, are either comparable to or surpass previous results obtained through much more sophisticated and computationally complex methods.
Abstract: Embedded zerotree wavelet (EZW) coding, introduced by Shapiro (see IEEE Trans. Signal Processing, vol.41, no.12, p.3445, 1993), is a very effective and computationally simple technique for image compression. We offer an alternative explanation of the principles of its operation, so that the reasons for its excellent performance can be better understood. These principles are partial ordering by magnitude with a set partitioning sorting algorithm, ordered bit plane transmission, and exploitation of self-similarity across different scales of an image wavelet transform. Moreover, we present a new and different implementation based on set partitioning in hierarchical trees (SPIHT), which provides even better performance than our previously reported extension of EZW that surpassed the performance of the original EZW. The image coding results, calculated from actual file sizes and images reconstructed by the decoding algorithm, are either comparable to or surpass previous results obtained through much more sophisticated and computationally complex methods. In addition, the new coding and decoding procedures are extremely fast, and they can be made even faster, with only small loss in performance, by omitting entropy coding of the bit stream by the arithmetic code.

5,890 citations

Journal ArticleDOI
TL;DR: Eight constructs decellularized hearts by coronary perfusion with detergents, preserved the underlying extracellular matrix, and produced an acellular, perfusable vascular architecture, competent a cellular valves and intact chamber geometry that could generate pump function in a modified working heart preparation.
Abstract: About 3,000 individuals in the United States are awaiting a donor heart; worldwide, 22 million individuals are living with heart failure. A bioartificial heart is a theoretical alternative to transplantation or mechanical left ventricular support. Generating a bioartificial heart requires engineering of cardiac architecture, appropriate cellular constituents and pump function. We decellularized hearts by coronary perfusion with detergents, preserved the underlying extracellular matrix, and produced an acellular, perfusable vascular architecture, competent acellular valves and intact chamber geometry. To mimic cardiac cell composition, we reseeded these constructs with cardiac or endothelial cells. To establish function, we maintained eight constructs for up to 28 d by coronary perfusion in a bioreactor that simulated cardiac physiology. By day 4, we observed macroscopic contractions. By day 8, under physiological load and electrical stimulation, constructs could generate pump function (equivalent to about 2% of adult or 25% of 16-week fetal heart function) in a modified working heart preparation.

2,454 citations

Journal ArticleDOI
01 Sep 1997
TL;DR: This paper examines automated iris recognition as a biometrically based technology for personal identification and verification from the observation that the human iris provides a particularly interesting structure on which to base a technology for noninvasive biometric assessment.
Abstract: This paper examines automated iris recognition as a biometrically based technology for personal identification and verification. The motivation for this endeavor stems from the observation that the human iris provides a particularly interesting structure on which to base a technology for noninvasive biometric assessment. In particular the biomedical literature suggests that irises are as distinct as fingerprints or patterns of retinal blood vessels. Further, since the iris is an overt body, its appearance is amenable to remote examination with the aid of a machine vision system. The body of this paper details issues in the design and operation of such systems. For the sake of illustration, extant systems are described in some amount of detail.

2,046 citations