611 research outputs found

    Measurement of disruption forces in JET using fiber-optic sensors

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    Monitoring the forces induced on the vacuum vessel when a disruption occurs is essential for the protection of the machine. Since divertor coils have been installed in JET, during disruptions a significant difference between the forces measured on the top and the bottom of the machine has been observed. In order to investigate these further, optical fiber transducers FBGs (Fiber Bragg Gratings) were installed in addition to the currently used strain gauges. During VDE (Vertical Displacement Event) tests, these new transducers were used to measure different level of disruptions ranging from 80T up to 230T vertical forces. The results were then compared with the strain gauges. The FBG measurement was carried out using a broadband light source illuminating an array of 4 FBGs through a combination of directional couplers, connectors and fiber-optic cable. The forces measured both by FBG and by the strain gauges are within the same range, except for the initial swing where large random differences are observed. The tests have demonstrated that the FBG-based force measurement system has adequate resolution (±1.52strain corresponding to a force of 4kN due to the geometry of the leg) and measurement range (50002strain or 13000kN) for this application

    Groupoids and an index theorem for conical pseudo-manifolds

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    We define an analytical index map and a topological index map for conical pseudomanifolds. These constructions generalize the analogous constructions used by Atiyah and Singer in the proof of their topological index theorem for a smooth, compact manifold MM. A main ingredient is a non-commutative algebra that plays in our setting the role of C0(TM)C_0(T^*M). We prove a Thom isomorphism between non-commutative algebras which gives a new example of wrong way functoriality in KK-theory. We then give a new proof of the Atiyah-Singer index theorem using deformation groupoids and show how it generalizes to conical pseudomanifolds. We thus prove a topological index theorem for conical pseudomanifolds

    Improper colourings inspired by Hadwiger’s conjecture

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    Hadwiger’s Conjecture asserts that every Kt-minor-free graph has a proper (t − 1)-colouring. We relax the conclusion in Hadwiger’s Conjecture via improper colourings. We prove that every Kt-minor-free graph is (2t − 2)-colourable with monochromatic components of order at most 1/2 (t − 2). This result has no more colours and much smaller monochromatic components than all previous results in this direction. We then prove that every Kt-minor-free graph is (t − 1)-colourable with monochromatic degree at most t − 2. This is the best known degree bound for such a result. Both these theorems are based on a decomposition method of independent interest. We give analogous results for Ks,t-minorfree graphs, which lead to improved bounds on generalised colouring numbers for these classes. Finally, we prove that graphs containing no Kt-immersion are 2-colourable with bounded monochromatic degree

    Infection prevention practices in the Netherlands: results from a National Survey

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    Objective: To examine the extent to which acute care hospitals in the Netherlands have adopted recommended practices to prevent catheter-associated urinary tract infection (CAUTI), central line-associated bloodstream infection (CLABSI), ventilator-associated pneumonia (VAP), and Clostridioides difficile infection (CDI). Methods: Between 18 July 2017 and 31 October 2017, we surveyed the infection prevention teams of all acute care hospitals in the Netherlands. The survey instrument was based on the 'Translating Healthcare-Associated Infection Prevention Research into Practice' (TRIP) questionnaire and adapted to the Dutch context. Descriptive statistics were used to examine the reported regular use of CAUTI, CLABSI, VAP, and CDI prevention practices as well as the hospital characteristics. Results: Out of 72 eligible hospitals, 47 (65.3%) responded. Surveillance systems for monitoring CAUTI, CLABSI, VAP, and CDI were present in 17.8, 95.4, 26.2, and 77.3% of hospitals, respectively. Antimicrobial stewardship programs have been established in 91.5% of participating hospitals. For CAUTI, the majority of hospitals regularly used aseptic technique during catheter insertion (95%) and portable bladder ultrasound scanners (86.1%). Intermittent catheterization and catheter stop-orders were regularly used by 65.8 and 62.2% of hospitals. For CLABSI, all hospitals regularly used maximum sterile barrier precautions and chlorhexidine gluconate for insertion site antisepsis. Avoidance of the femoral site for central line insertions was regularly used by 65.9% of hospitals. Urinary catheters and central-lines impregnated with antibiotics or antiseptics were rarely used (≤ 5%). Selective decontamination strategies for preventing VAP were used in 84% of hospitals. With the exception of disposable thermometers (31.8%), all prevention practices to prevent CDI were regularly used by more

    Provision of care services for rheumatic and musculoskeletal diseases-related foot and ankle problems: a survey from sixteen european countries

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    DOI:10.1136/annrheumdis-2016-eular.4435Background: The increased prevalence of foot and ankle pathologies in Rheumatic and Musculoskeletal diseases (RMDs) is well documented1, however the provision of foot & ankle (F&A) healthcare services for people with RMDs in Europe has not been evaluated. Objectives: To assess the current healthcare systems for providing foot & ankle healthcare services for people with RMDs in Europe. Methods: A survey was undertaken to evaluate current provision of F&A health care services for people with RMDs across Europe. A questionnaire was distributed to all 22 country presidents representing HP associations within EULAR. The questionnaire used was developed and piloted (in 7 countries) by the EULAR F&A Study Group, and structured to capture the provision and type of F&A services for people with RMDs. When the HP presidents felt unable to answer specific questions they were encouraged to consult a colleague who may be better placed to provide the answers. Results: Sixteen questionnaires were completed (Norway, Ireland, Sweden, Hungary, Netherlands, UK, Denmark, Portugal, Italy, Switzerland, Austria, France, Czech Republic, Spain, Belgium, Malta). Of the 16, 13 respondents indicated provision of F&A health care services in their country, but only three countries had services specialising in RMD-related F&A problems (Netherlands, UK, Malta). The professions providing the care for patients with RMD-related F&A problems were different depending on the pathology and the country (Table1). Podiatrists provided care for F&A pain and deformity problems in 11 countries, but provided F&A ulcer care in only 8 countriesConclusions: Only 3 countries have F&A health care services specialised to the needs of people with RMDs. The professions providing the care varied between countries, and also depended on the F&A pathology. Interestingly, F&A healthcare services were provided by professions that do not solely specialised in F&A care. Further research is needed to assess the variation of F&A healthcare services between and within European countries and the impact on healthcare of various F&A healthcare service designs. References: Woodburn, J. & Helliwell, P. Foot problems in rheumatology. Rheumatology 36, 932-934 (1997).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Evaluation of the chagas western blot igg assay for the diagnosis of chagas disease

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    Chagas disease is a debilitating and often fatal pathology resulting from infection by the protozoan parasite Trypanosoma cruzi. In its recommendations, the World Health Organization states that the diagnosis of T. cruzi infection is usually based on the detection of antibodies against T. cruzi antigens and performed with two methodologically different assays. An inconclusive result can be resolved with a third “confirmatory” assay. The objective of this article is to evaluate the effectiveness of the Chagas Western Blot IgG assay (LDBio Diagnostics, Lyon, France) as a confirmatory serologic test. The Chagas Western Blot IgG assay was performed with native antigens derived from a T. cruzi strain of the TcVI genotype. Retrospective sera were provided by two parasitology laboratories (France and Argentina). The sensitivity, specificity, positive predictive value and negative predictive value of the Chagas blot were all 100% in our sera collection. The Chagas blot is an easy and qualitative method for the diagnosis of Chagas disease, with results in less than 2 h. This immunoblot has potential as a supplemental test for the confirmation of the presence of antibodies against T. cruzi in serum specimens. Nonetheless, the very good initial results presented here will need to be confirmed in larger studies.Fil: Brossas, Jean Yves. Sorbonne Université Hôpital Pitié-Salpêtrière; FranciaFil: Ballering, Griselda Edith. Gobierno de la Ciudad de Buenos Aires. Instituto Multidisciplinario de Investigaciones en Patologías Pediátricas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto Multidisciplinario de Investigaciones en Patologías Pediátricas; ArgentinaFil: Bisio, Margarita María Catalina. Gobierno de la Ciudad de Buenos Aires. Instituto Multidisciplinario de Investigaciones en Patologías Pediátricas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto Multidisciplinario de Investigaciones en Patologías Pediátricas; ArgentinaFil: Guihenneuc, Jeremy. Sorbonne Université Hôpital Pitié-Salpêtrière; FranciaFil: Gulin, Julián Ernesto Nicolás. Gobierno de la Ciudad de Buenos Aires. Instituto Multidisciplinario de Investigaciones en Patologías Pediátricas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto Multidisciplinario de Investigaciones en Patologías Pediátricas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Jauréguiberry, S.. Sorbonne Université Hôpital Pitié-Salpêtrière; FranciaFil: Lescure, François Xavier. Hôpitaux Universitaires Paris Nord val de Seine; FranciaFil: Fekkar, Arnaud. Sorbonne Université Hôpital Pitié-Salpêtrière; FranciaFil: Mazier, Dominique. Sorbonne University; FranciaFil: Altcheh, Jaime Marcelo. Gobierno de la Ciudad de Buenos Aires. Instituto Multidisciplinario de Investigaciones en Patologías Pediátricas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto Multidisciplinario de Investigaciones en Patologías Pediátricas; ArgentinaFil: Paris, Luc. Sorbonne Université Hôpital Pitié-Salpêtrière; Franci

    Tiny abortive initiation transcripts exert antitermination activity on an RNA hairpin-dependent intrinsic terminator

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    No biological function has been identified for tiny RNA transcripts that are abortively and repetitiously released from initiation complexes of RNA polymerase in vitro and in vivo to date. In this study, we show that abortive initiation affects termination in transcription of bacteriophage T7 gene 10. Specifically, abortive transcripts produced from promoter ϕ10 exert trans-acting antitermination activity on terminator Tϕ both in vitro and in vivo. Following abortive initiation cycling of T7 RNA polymerase at ϕ10, short G-rich and oligo(G) RNAs were produced and both specifically sequestered 5- and 6-nt C + U stretch sequences, consequently interfering with terminator hairpin formation. This antitermination activity depended on sequence-specific hybridization of abortive transcripts with the 5′ but not 3′ half of Tϕ RNA. Antitermination was abolished when Tϕ was mutated to lack a C + U stretch, but restored when abortive transcript sequence was additionally modified to complement the mutation in Tϕ, both in vitro and in vivo. Antitermination was enhanced in vivo when the abortive transcript concentration was increased via overproduction of RNA polymerase or ribonuclease deficiency. Accordingly, antitermination activity exerted on Tϕ by abortive transcripts should facilitate expression of Tϕ-downstream promoter-less genes 11 and 12 in T7 infection of Escherichia coli
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