600 research outputs found

    A data-fusion approach to motion-stereo

    Get PDF
    This paper introduces a novel method for performing motion--stereo, based on dynamic integration of depth (or its proxy) measures obtained by pairwise stereo matching of video frames. The focus is on the data fusion issue raised by the motion--stereo approach, which is solved within a Kalman filtering framework. Integration occurs along the temporal and spatial dimension, so that the final measure for a pixel results from the combination of measures of the same pixel in time and whose of its neighbors. The method has been validated on both synthetic and natural images, using the simplest stereo matching strategy and a range of different confidence measures, and has been compared to baseline and optimal strategies

    Robust Global Motion Estimation with Matrix Completion

    Get PDF
    In this paper we address the problem of estimating the attitudes and positions of a set of cameras in an external coordinate system. Starting from a conventional global structure-from-motion pipeline, we present some substantial advances. In order to detect outlier relative rotations extracted from pairs of views, we improve a state-of-the-art algorithm based on cycle consistency, by introducing cycle bases. We estimate the angular attitudes of the cameras by proposing a novel gradient descent algorithm based on low-rank matrix completion, that naturally copes with the case of missing data. As for position recovery, we analyze an existing technique from a theoretical point of view, providing some insights on the conditions that guarantee solvability. We provide experimental results on both synthetic and real image sequences for which ground truth calibration is provided

    KRAS testing in metastatic colorectal carcinoma: challenges, controversies, breakthroughs, and beyond

    Get PDF
    Metastatic colorectal cancer harboring a mutation in codon 12 or 13 of the KRAS gene does not benefit from therapy with antibodies targeting the epidermal growth factor receptor (EGFR). The implementation of community KRAS testing is generating a rapid flow of new data that have implications for the pathologist and testing guidelines, besides the physician. Therefore, it seems timely to draw together the threads of this large body of information in order that pathologists can be knowledgeable partners in the multidisciplinary process of targeted cancer therapy, and to help refine current testing guidelines. This review addresses: (1) the most relevant methodological and technical aspects of KRAS testing in terms of sample site (primary/metastatic), test specimens (resection/biopsy/cytology), and the diverse molecular methods available; (2) issues related to daily practice, namely the timing of the test, its turnaround time and the quality control procedures; and (3) the evidence related to the relationship between KRAS genetic intratumoral heterogeneity, clinical sensitivity of mutational detection tools and anti-EGFR treatment outcome. Hopefully, in the near future, elucidation of the potential of biomarker panels, and of the mechanisms underlying primary and acquired resistance to anti-EGFR therapy will refine even further personalized treatment regimes for patients with metastatic colorectal cancer

    Liquid Biopsy: A New Diagnostic Strategy and Not Only for Lung Cancer?

    Get PDF
    Targeted molecular therapies have significantly improved the therapeutic management of advanced lung cancer. The possibility of detecting lung cancer at an early stage is surely an important event in order to improve patient survival. Liquid biopsy has recently demonstrated its clinical utility in advanced non-small cell lung cancer (NSCLC) as a possible alternative to tissue biopsy for non-invasive evaluation of specific genomic alterations, thus providing prognostic and predictive information when the tissue is difficult to find or the material is not sufficient for the numerous investigations to be carried out. Several biosources from liquid biopsy, including free circulating tumor DNA (ctDNA) and RNA (ctRNA), circulating tumor cells (CTCs), exosomes and tumor-educated platelets (TEPs), have been extensively studied for their potential role in the diagnosis of lung cancer. This chapter proposes an overview of the circulating biomarkers assessed for the detention and monitoring of disease evolution with a particular focus on cell-free DNA, on the techniques developed to perform the evaluation and on the results of the most recent studies. The text will analyze in greater depth the liquid biopsy applied to the clinical practice of the management of NSCLC

    Automatic 3DS Conversion of Historical Aerial Photographs

    Get PDF
    In this paper we present a method for the generation of 3D stereo (3DS) pairs from sequences of historical aerial photographs. The goal of our work is to provide a stereoscopic display when the existing exposures are in a monocular sequence. Each input image is processed using its neighbours and a synthetic image is rendered, which, together with the original one, form a stereo pair. Promising results on real images taken from a historical photo archive are shown, that corroborate the viability of generating 3DS data from monocular footage

    cost effective quality assessment in industrial parts manufacturing via optical acquisition

    Get PDF
    Abstract We tackle the problem of dimensional verification via optical acquisition systems in the context of industrial manufacturing processes. Optical methods for quality inspection play a crucial part in the transition process to industry 4.0 and, despite the lack of international standardization, several solutions are available to industries that need to provide dimensional verification to their customers. Unfortunately most of these solutions are still economically unavailable to the majority of small or medium companies. In this paper we present an optical system based on low-cost components and we demonstrate that it provides useful and reliable information in quality inspection procedures

    Prognostic factors and biomarkers of responses to immune checkpoint inhibitors in lung cancer

    Get PDF
    Manipulation of the immune response is a game changer in lung cancer treatment, revolutionizing management. PD1 and CTLA4 are dynamically expressed on different T cell subsets that can either disrupt or sustain tumor growth. Monoclonal antibodies (MoAbs) against PD1/PDL1 and CTLA4 have shown that inhibitory signals can be impaired, blocking T cell activation and function. MoAbs, used as both single-agents or in combination with standard therapy for the treatment of advanced non-small cell lung cancer (NSCLC), have exhibited advantages in terms of overall survival and response rate; nivolumab, pembrolizumab, atezolizumab and more recently, durvalumab, have already been approved for lung cancer treatment and more compounds are in the pipeline. A better understanding of signaling elicited by these antibodies on T cell subsets, as well as identification of biological determinants of sensitivity, resistance and correlates of efficacy, will help to define the mechanisms of antitumor responses. In addition, the relevance of T regulatory cells (Treg) involved in immune responses in cancer is attracting increasing interest. A major challenge for future research is to understand why a durable response to immune checkpoint inhibitors (ICIs) occurs only in subsets of patients and the mechanisms of resistance after an initial response. This review will explore current understanding and future direction of research on ICI treatment in lung cancer and the impact of tumor immune microenvironment n influencing clinical responses

    Evaluation of EGFR mutation status in cytology specimens: An institutional experience

    Full text link
    Epidermal growth factor receptor ( EGFR ) mutation status has been shown to predict response to anti‐EGFR tyrosine kinase inhibitors in non‐small cell lung cancer (NSCLC). In patients with advanced‐stage NSCLC, evaluation of mutational status is increasingly requested on biopsy or fine‐needle aspiration specimens, which often have limited material. There are limited data on the suitability of cytology cell blocks (CB) for EGFR mutation testing. In this study, we report our institutional experience with cytology cell block material for EGFR mutation testing. We retrospectively reviewed EGFR mutation analyses performed on 234 surgical (SP) and cytology (CB) from October 2007 to May 2010. One hundred ninety‐two SP specimens and 42 CB specimens were evaluated for EGFR mutation. CB specimens were evaluated for overall specimen size based on aggregate cellularity in comparison to small biopsy specimens, and percent tumor. Of the 192 SP and 42 CB specimens, 31 (16.1%) and 11 (26.2%) were positive for EGFR mutation, respectively; there does not appear to be an association between mutation detection rate and the source of the specimen ( P = 0.124). Limited DNA was obtained from 70.0% (29/42), including 81.8% (9/11) of those which were mutation positive. Additionally, 45.4% (5/11) of mutation positive specimens had extremely low DNA yields. Although 16.6% (7/42) of CB specimens had 10% tumor. These data indicate that CB specimens provide an alternative source for molecular evaluation of NSCLC, and that tumor percentage may be more important than specimen size and/or DNA yield in determining the suitability of these specimens for testing. Diagn. Cytopathol. 2013;41:316–323. © 2011 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97174/1/21851_ftp.pd
    • 

    corecore