Immunohistochemical detection of scrapie prion proteins in clinically normal sheep in Pennsylvania

Following diagnosis of scrapie in a clinically suspect Suffolk sheep, 7 clinically normal flockmates were purchased by the Pennsylvania Department of Agriculture to determine their scrapie status using an immunohistochemical procedure. Two of the 7 euthanized healthy sheep had positive immunohistochemical staining of the prion protein of scrapie (PrP-Sc) in their brains, nictitating membranes, and tonsils. The PrP-Sc was localized in the areas of the brain where, histopathologically, there was neurodegeneration and astrocytosis. The PrP-Sc occurred within germinal centers of the affected nictitating membranes and tonsils and was located in the cytoplasm of the dendrite-like cells, lymphoid cells, and macrophages. These results confirm that immunohistochemical examination of the nictitating membrane can be used as a screen for the presence of scrapie infection in clinically normal sheep at a capable veterinary diagnostic laboratory. In sheep with a PrP-Sc–positive nictitating membrane, the diagnosis of scrapie should be confirmed by histopathology and immunohistochemical examination of the brain following necropsy. Following full validation, immunohistochemistry assays for detection of PrP-Sc in nictitating membrane lymphoid tissues can improve the effectiveness of the scrapie control and eradication program by allowing diagnosis of the disease in sheep before the appearance of clinical signs

GiViP: A Visual Profiler for Distributed Graph Processing Systems

Analyzing large-scale graphs provides valuable insights in different application scenarios. While many graph processing systems working on top of distributed infrastructures have been proposed to deal with big graphs, the tasks of profiling and debugging their massive computations remain time consuming and error-prone. This paper presents GiViP, a visual profiler for distributed graph processing systems based on a Pregel-like computation model. GiViP captures the huge amount of messages exchanged throughout a computation and provides an interactive user interface for the visual analysis of the collected data. We show how to take advantage of GiViP to detect anomalies related to the computation and to the infrastructure, such as slow computing units and anomalous message patterns.Comment: Appears in the Proceedings of the 25th International Symposium on Graph Drawing and Network Visualization (GD 2017

Levofloxacin versus placebo for the prevention of tuberculosis disease in child contacts of multidrug-resistant tuberculosis: study protocol for a phase III cluster randomised controlled trial (TB-CHAMP)

Background Multidrug-resistant (MDR) tuberculosis (TB) presents a challenge for global TB control. Treating individuals with MDR-TB infection to prevent progression to disease could be an effective public health strategy. Young children are at high risk of developing TB disease following infection and are commonly infected by an adult in their household. Identifying young children with household exposure to MDR-TB and providing them with MDR-TB preventive therapy could reduce the risk of disease progression. To date, no trials of MDR-TB preventive therapy have been completed and World Health Organization guidelines suggest close observation with no active treatment. Methods The tuberculosis child multidrug-resistant preventive therapy (TB-CHAMP) trial is a phase III cluster randomised placebo-controlled trial to assess the efficacy of levofloxacin in young child contacts of MDR-TB cases. The trial is taking place at three sites in South Africa where adults with MDR-TB are identified. If a child aged < 5 years lives in their household, we assess the adult index case, screen all household members for TB disease and evaluate any child aged < 5 years for trial eligibility. Eligible children are randomised by household to receive daily levofloxacin (15–20 mg/kg) or matching placebo for six months. Children are closely monitored for disease development, drug tolerability and adverse events. The primary endpoint is incident TB disease or TB death by one year after recruitment. We will enrol 1556 children from approximately 778 households with an average of two eligible children per household. Recruitment will run for 18–24 months with all children followed for 18 months after treatment. Qualitative and health economic evaluations are embedded in the trial. Discussion If the TB-CHAMP trial demonstrates that levofloxacin is effective in preventing TB disease in young children who have been exposed to MDR-TB and that it is safe, well tolerated, acceptable and cost-effective, we would expect that that this intervention would rapidly transfer into policy. Trial registration ISRCTN Registry, ISRCTN92634082. Registered on 31 March 2016

Distributed Bragg Pulse Shapers for Terahertz Modulation and Ultrafast Communications

128 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1998.The operation of the DBPS is modeled using coupled-mode theory, and a simulation of the device is presented that accurately reproduces observed data. The simulation is used to model pulse shapers with ideal characteristics. The magnitude and speed of the electrically induced refractive index change, which is the mechanism responsible for switching in the DBPS, are discussed. Several problems and technical challenges with the current generation of experimental devices are presented, and solutions are proposed which may in the future make the DBPS and CDM system a viable alternative for ultrafast communications.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Peter Kropotkin: ecologist, philosopher and revolutionary

The Problem Investigated:This thesis is conceived as: [1] a work of scholarship and exegesis [2] an examination of more recent scientific works which use similar metaphors or concepts, eg. Cooperation, that are central to Kropotkin's thinking. As a work of scholarship and exegesis this thesis is an attempt to present the many areas/dimensions of Kropotkin's philosophy and thinking in a systematic way. I do not believe that this has been attempted previously in any language. Although his political, social and economic theories have generated a substantial secondary literature, Kropotkin's scientific works and philosophy of science, with the exception of his famous book, Mutual Aid, have received virtually no attention. In consequence of this the emphasis of this work will be upon his scientific writings. However, his political writings will also be examined as well as related to his broad scientific outlook.In addition to evaluating Kropotkin's scientific works in relation to his period I also discuss them in relation to contemporary debates. Although not strictly true, the second half of this thesis is not a work of historical scholarship but an attempt to bring together the ideas of scientists that in one way or another support a Kropotkinesque characterisation of natural processes.Although Kropotkin is often rightly regarded as a founder of modern environmentalism, this is difficult to substantiate from his purely political and social writings. Thus I will attempt to present the core concepts of Kropotkin's anarchism in a coherent and succinct way with an emphasis upon showing how they relate to contemporary debates and perspectives within the environmental movement. The Procedures Followed:The thesis will be introduced biographically. This seemed the best way to introduce Kropotkin's works to the reader and place them in relation to one another and in their historical context. Thus the primary purpose of this historical section is to contextualise the great diversity of works by Kropotkin.As I do not have a science background, but also for reasons of clarity, the remainder of the analysis shall be based upon the least technical and most accessible scientific literature in the various disciplines investigated.I will begin by systematically collecting, cataloguing and analysing both Kropotkin's works as well as the secondary literature and then proceed to make some overall sense of them and then relate them to contemporary debates upon process and organisation in nature and society.The General Results Obtained:My research has revealed a large body of scientific work by Kropotkin. My analysis of them shows that he had a deep understanding of the role of mutualism, symbiosis, dynamism, group and social behaviour etc., in relation to physical and biological processes. His ideas, although necessarily containing errors, are broadly, as well as in many detailed aspects, consistent with the findings of professional, though often unorthodox, scientists of the present day.The main faults of Kropotkin's approach was a fundamental failure to appreciate the role of territories and hierarchies in animal groups and his excessive progressivism. My research also reveals how Kropotkin's social vision, although somewhat utopian, can be sympathetically interpreted in terms of modern environmentalist perspectives.The Major Conclusions Reached:Kropotkin's diverse works in science and social theory when presented systematically reveals that he is a philosopher of considerable interest in respect to both contemporary and historical debates concerning sociality and its influence upon the evolution of life on Earth