471 research outputs found
How to Recover a Qubit That Has Fallen Into a Black Hole
We demonstrate an algorithm for the retrieval of a qubit, encoded in spin
angular momentum, that has been dropped into a no-firewall black hole.
Retrieval is achieved analogously to quantum teleportation by collecting
Hawking radiation and performing measurements on the black hole. Importantly,
these methods only require the ability to perform measurements from outside the
event horizon.Comment: 6 pages v2: modified protocol to discuss total angular momentum,
corrected typos, added references v3: updated with referee feedbac
Indexing of mid-resolution satellite images with structural attributes.
Satellite image classification has been a major research field for many years with its varied applications in the field of Geography,
Geology, Archaeology, Environmental Sciences and Military purposes. Many different techniques have been proposed to classify
satellite images with color, shape and texture features. Complex indices like Vegetation index (NDVI), Brightness index (BI) or
Urban index (ISU) are used for multi-spectral or hyper-spectral satellite images. In this paper we will show the efficiency of
structural features describing man-made objects in mid-resolution satellite images to describe image content. We will then show the
state-of-the-art to classify large satellite images with structural features computed from road networks and urban regions extracted
on small image patches cut in the large image. Fisher Linear Discriminant (FLD) analysis is used for feature selection and a one-vsrest
probabilistic Gaussian kernel Support Vector Machines (SVM) classification method is used to classify the images. The
classification probabilities associated with each subimage of the large image provide an estimate of the geographical class coverage
Coupled Oscillators with Chemotaxis
A simple coupled oscillator system with chemotaxis is introduced to study
morphogenesis of cellular slime molds. The model successfuly explains the
migration of pseudoplasmodium which has been experimentally predicted to be
lead by cells with higher intrinsic frequencies. Results obtained predict that
its velocity attains its maximum value in the interface region between total
locking and partial locking and also suggest possible roles played by partial
synchrony during multicellular development.Comment: 4 pages, 5 figures, latex using jpsj.sty and epsf.sty, to appear in
J. Phys. Soc. Jpn. 67 (1998
Vibrational spectroscopy: a promising approach to discriminate neurodegenerative disorders
Neurodegenerative diseases are a growing burden in modern society, thus crucially calling for the development of accurate diagnostic strategies. These diseases are currently incurable, a fact which has been attributed to their late diagnosis, after brain damage has already become widespread. An earlier and improved diagnosis is necessary for the enrolment of patients into clinical trials and can pave the way for the development of therapeutic tactics. Novel analytical techniques, such as mass spectrometry and vibrational spectroscopy, have been able to successfully detect and characterise neurodegenerative disorders. It is critical to globally support and make use of innovative basic research and techniques, which could ultimately lead to the creation of a cost-effective diagnostic test. Minimally invasive samples, such as biological fluids, have also been shown to reveal information for these diseases; utilising them could simplify sample collection/analysis and be more preferable to patients
How to humiliate and shame: A reporter's guide to the power of the mugshot
This is an Author's Accepted Manuscript of an article published in Social Semiotics, 24(1), 56-87, 2014, copyright Taylor & Francis, available online at: http://www.tandfonline.com/The judicial photograph – the “mugshot” – is a ubiquitous and instantly recognisable form, appearing in the news media, on the internet, on book covers, law enforcement noticeboards and in many other mediums. This essay attempts to situate the mugshot in a historical and theoretical context to explain the explicit and implicit meaning of the genre as it has developed, focussing in particular on their use in the UK media in late modernity. The analysis is based on the author's reflexive practice as a journalist covering crime in the national news media for 30 years and who has used mugshots to illustrate stories for their explicit and specific content. The author argues that the visual limitations of the standardised “head and shoulders” format of the mugshot make it a robust subject for analysing the changing meaning of images over time. With little variation in the image format, arguments for certain accreted layers of signification are easier to make. Within a few years of the first appearance of the mugshot form in the mid-19th century, it was adopted and adapted as a research tool by scientists and criminologists. While the positivist scientists claimed empirical objectivity we can now see that mugshots played a part in the construction of subjective notions of “the other”, “the lesser” or “sub-human” on the grounds of class, race and religion. These dehumanising ideas later informed the theorists and bureaucrats of National Socialist ideology from the 1920s to 1940s. The author concludes that once again the mugshot has become, in certain parts of the media, a signifier widely used to exclude or deride certain groups. In late modernity, the part of the media that most use mugshots – the tabloid press and increasingly tabloid TV – is part of a neo-liberal process that, in a conscious commercial appeal to the paying audience, seeks to separate rather than unify wider society
Citizen surveil-labour: Analysing Crime Stoppers and its alliance of police, media, and publics
Cell-type specific RNA-Seq reveals novel roles and regulatory programs for terminally differentiated Dictyostelium cells
Abstract Background A major hallmark of multicellular evolution is increasing complexity by the evolution of new specialized cell types. During Dictyostelid evolution novel specialization occurred within taxon group 4. We here aim to retrace the nature and ancestry of the novel “cup” cells by comparing their transcriptome to that of other cell types. Results RNA-Seq was performed on purified mature spore, stalk and cup cells and on vegetative amoebas. Clustering and phylogenetic analyses showed that cup cells were most similar to stalk cells, suggesting that they share a common ancestor. The affinity between cup and stalk cells was also evident from promoter-reporter studies of newly identified cell-type genes, which revealed late expression in cups of many stalk genes. However, GO enrichment analysis reveal the unexpected prominence of GTPase mediated signalling in cup cells, in contrast to enrichment of autophagy and cell wall synthesis related transcripts in stalk cells. Combining the cell type RNA-Seq data with developmental expression profiles revealed complex expression dynamics in each cell type as well as genes exclusively expressed during terminal differentiation. Most notable were nine related hssA-like genes that were highly and exclusively expressed in cup cells. Conclusions This study reveals the unique transcriptomes of the mature cup, stalk and spore cells of D. discoideum and provides insight into the ancestry of cup cells and roles in signalling that were not previously realized. The data presented in this study will serve as an important resource for future studies into the regulation and evolution of cell type specialization
Phase field models and higher-order active contours
The representation and modelling of regions is an important topic in computer vision. In this paper, we represent a region via a level set of a 'phase field' function. The function is not constrained, e.g. to be a distance function; nevertheless, phase field energies equivalent to classical active contour energies can be defined. They represent an advantageous alternative to other methods: a linear representation space; ease of implementation (a PDE with no reinitialization); neutral initialization; greater topological freedom. We extend the basic phase field model with terms that reproduce 'higher-order active contour' energies, a powerful way of including prior geometric knowledge in the active contour framework via nonlocal interactions between contour points, in addition to the above advantages, the phase field greatly simplifies the analysis and implementation of the higher-order terms. We define a phase field model that favours regions composed of thin arms meeting at junctions, combine this with image terms, and apply the model to the extraction of line networks from remote sensing images
Gap Closure in (Road) Networks Using Higher-Order Active Contours
We present a new model for the extraction of networks from images in the presence of occlusions. Such occlusions cause gaps in the extracted network that need to he closed. Using higher-order active contours, which allow the incorporation of sophisticated geometric information, we introduce a new, non-local, 'gap closure' force that causes pairs of network extremities that are close together to extend towards one another and join, thus closing the gap between them. We demonstrate the benefits of the model using the problem of road network extraction, presenting results on aerial images
Lattice Green functions and diffusion for modelling traffic routing in ad hoc networks
We describe basic properties of Markov chains on finite state spaces and their application to Green functions, partial differential equations, and their (approximate) solution using random walks on a graph. Attention is paid to the influence of boundary conditions (Dirichlet/von Neumann). We apply these ideas to the study of traffic propagation and distribution in ad hoc networks
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