Barcode Annotations for Medical Image Retrieval: A Preliminary Investigation

This paper proposes to generate and to use barcodes to annotate medical images and/or their regions of interest such as organs, tumors and tissue types. A multitude of efficient feature-based image retrieval methods already exist that can assign a query image to a certain image class. Visual annotations may help to increase the retrieval accuracy if combined with existing feature-based classification paradigms. Whereas with annotations we usually mean textual descriptions, in this paper barcode annotations are proposed. In particular, Radon barcodes (RBC) are introduced. As well, local binary patterns (LBP) and local Radon binary patterns (LRBP) are implemented as barcodes. The IRMA x-ray dataset with 12,677 training images and 1,733 test images is used to verify how barcodes could facilitate image retrieval.Comment: To be published in proceedings of The IEEE International Conference on Image Processing (ICIP 2015), September 27-30, 2015, Quebec City, Canad

Gauge field corrections to 11-dimensional supergravity via dimensional reduction

Using the fact that eleven-dimensional supergravity yields type IIA supergravity under dimensional reduction on a circle, we determine higher-derivative terms of 11-dimensional supergravity including the $R^4$, $({\partial {F_4}})^2 R^2$ and $({\partial {F_4}})^4$ terms.Comment: 12 pages, LaTex file, no figure, v2: Published version in EPJ

Two Ramond-Ramond corrections to type II supergravity via field-theory amplitude

Motivated by the standard form of string-theory amplitude, we calculate the field-theory amplitude to complete the higher-derivative terms in type II supergravity theories in their conventional form. We derive explicitly the $O(\alpha'^3)$ interactions for the RR (Ramond-Ramond) fields with graviton, B-field and dilaton in the low-energy effective action of type II superstrings. We check our results by comparison with previous works that have been done by the other methods, and find an exact agreement.Comment: 17 pages, no figure, v2: Published version in EPJ

Pelvic Organ Prolapse-Associated Cystitis

This thesis concerns the construction of 2,3-dihydro-4r7-pyran-4-one and 3(2//)-furanone ring systems by mercury(II)-catalysed reactions, or by more conventional cyclisations, and the potential of such reactions for the synthesis of natural products. Chapter one provides a literature survey of reactions permitting the construction of 2,3-dihydro-4/7-pyran-4-one and 3(2//)-furanone ring systems background literature to relevant natural products is also provided, such as polyether antibiotics, carbohydrates and antitumer agents. Chapter two describes the application of mercury(II)-catalysed cyclisations of dihydroxylated ynones to give 3(2//)-furanones this was achieved by the dihydroxylation of enynones using Sharpless's asymmetric dihydroxylation conditions followed by treatment with a mecury(II) catalyst. The scope and limitations of this method were investigated and shown in several cases to give good yields and high enantiomeric excess. In cases where there was an electron-donating group on the alkyne functionality, such as an ethoxy group, the cyclisation occurred spontaneously during the dihydroxylation step. This methodology was applied for the synthesis of a natural product to confirm the selectivity of the cyclisation step. In chapter three the reactions developed in chapter two formed the basis of a proposed route to the natural product (-)-Pestalotin, a gibberellins synergist. Thus, the Sharpless asymmetric dihydroxylation method was applied to (3,y-unsaturated ketones to give a main intermediate for the synthesis. Chapter four details different approaches to NK10958P, a plant growth regulator. The synthesis of two main fragments was achieved and the coupling of these fragments by syn-selective aldol addition is expected to furnish NK10958 P and its methyl analogue, pironetin, which has been reported to have good cytotoxic and immunosuppressive activity. Full experimental details follow chapter 2-4 and reference sections are provided at the end of each chapter

Sphere-level Ramond-Ramond couplings in Ramond-Neveu-Schwarz formalism

We calculate in details the sphere-level scattering amplitude of two Ramond-Ramond (RR) and two Neveu-Schwarz-Neveu-Schwarz (NSNS) vertex operators in type II superstring theories in Ramond-Neveu-Schwarz (RNS) formalism. We then compare the expansion of this amplitude at order $\alpha'^3$ with the eight-derivative couplings of the gravity and B-field that have been recently found based on S-dual and T-dual Ward identities. We find exact agreement. Moreover, using the above S-matrix element, we have found various couplings involving the dilaton field, and shown that they are also fully consistent with these Ward identities.Comment: 34 pages, Latex file, no figure; v3: the version appears in np

On Being Religious

The question of religion, in one form or another, has been with us humans for millennia. From primitive tribal ceremonies to highly organized scriptures and theological rule books, up to excruciatingly circumlocutory philosophical treatises, we - Homo sapiens - have attempted to answer the question of religion through ages. Perhaps the most paramount question is whether religion is a real phenomenon that exists outside of us or whether we have invented it. If we have constructed the concept of religion, then our understanding of religion and any action emerging from it would be about us, humans, would it not? If religion is true|something of substance that exists outside and beyond humanity|then we are, as sentient beings with consciousness, mere explorers and we cannot be its inventors, can we? What does this mean? Does this mean there could be no religion without human involvement? Does this mean religion can only manifest itself in a human-centric universe? If so, why is that

Information-seeking behaviour of physicists and astronomers

Purpose – The study examines two aspects of information seeking behaviour of physicists and astronomers including methods applied for keeping up-to-date and methods used for finding articles. The relationship between academic status and research field of users with their information seeking behaviour was investigated. Methodology/approach – Data were gathered using a questionnaire survey of PhD students and staff of the Department of Physics and Astronomy at University College London; 114 people (47.1 per cent response rate) participated in the survey. Findings – The study reveals differences among subfields of physics and astronomy in terms of information-seeking behaviour, highlights the need for and the value of looking at narrower subject communities within disciplines for a deeper understanding of the information behaviour of scientists. Originality/value – The study is the first study to deeply investigate intradisciplinary dissimilarities of information-seeking behaviour of scientists in a discipline. It is also an up-to-date account of information seeking behaviour of physicists and astronomers