854 research outputs found

    Event Data Definition in LHCb

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    We present the approach used for defining the event object model for the LHCb experiment. This approach is based on a high level modelling language, which is independent of the programming language used in the current implementation of the event data processing software. The different possibilities of object modelling languages are evaluated, and the advantages of a dedicated model based on XML over other possible candidates are shown. After a description of the language itself, we explain the benefits obtained by applying this approach in the description of the event model of an experiment such as LHCb. Examples of these benefits are uniform and coherent mapping of the object model to the implementation language across the experiment software development teams, easy maintenance of the event model, conformance to experiment coding rules, etc. The description of the object model is parsed by means of a so called front-end which allows to feed several back-ends. We give an introduction to the model itself and to the currently implemented back-ends which produce information like programming language specific implementations of event objects or meta information about these objects. Meta information can be used for introspection of objects at run-time which is essential for functionalities like object persistency or interactive analysis. This object introspection package for C++ has been adopted by the LCG project as the starting point for the LCG object dictionary that is going to be developed in common for the LHC experiments. The current status of the event object modelling and its usage in LHCb are presented and the prospects of further developments are discussed.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 7 pages, LaTeX, 2 eps figures. PSN MOJT00

    chemical composition and antimicrobial activity of the essential oil from the bark of xylopia hypolampra

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    Hydrodistillation of Xylopia hypolampra Mildbr. stem bark afforded 39 mg (dry weight basis) of a pale yellow fragrant essential oil; gas chromatography-flame ionization detector and gas chromatogra..

    The LHCb ultra-fast simulation option, Lamarr: design and validation

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    Detailed detector simulation is the major consumer of CPU resources at LHCb, having used more than 90% of the total computing budget during Run 2 of the Large Hadron Collider at CERN. As data is collected by the upgraded LHCb detector during Run 3 of the LHC, larger requests for simulated data samples are necessary, and will far exceed the pledged resources of the experiment, even with existing fast simulation options. An evolution of technologies and techniques to produce simulated samples is mandatory to meet the upcoming needs of analysis to interpret signal versus background and measure efficiencies. In this context, we propose Lamarr, a Gaudi-based framework designed to offer the fastest solution for the simulation of the LHCb detector. Lamarr consists of a pipeline of modules parameterizing both the detector response and the reconstruction algorithms of the LHCb experiment. Most of the parameterizations are made of Deep Generative Models and Gradient Boosted Decision Trees trained on simulated samples or alternatively, where possible, on real data. Embedding Lamarr in the general LHCb Gauss Simulation framework allows combining its execution with any of the available generators in a seamless way. Lamarr has been validated by comparing key reconstructed quantities with Detailed Simulation. Good agreement of the simulated distributions is obtained with two-order-of-magnitude speed-up of the simulation phase.Comment: Under review in EPJ Web of Conferences (CHEP 2023

    Energy deposition studies for the Upgrade II of LHCb at the CERN Large Hadron Collider

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    The Upgrade II of the LHCb experiment is proposed to be installed during the CERN Long Shutdown 4, aiming to operate LHCb at 1.5x1034cm−2s−110^{34}cm^{-2}s^{-1} that is 75 times its design luminosity and reaching an integrated luminosity of about 400fb−1400 fb^{-1} by the end of the High Luminosity LHC era. This increase of the data sample at LHCb is an unprecedented opportunity for heavy flavour physics measurements. A first upgrade of LHCb, completed in 2022, has already implemented important changes of the LHCb detector and, for the Upgrade II, further detector improvements are being considered. Such a luminosity increase will have an impact not only on the LHCb detector but also on the LHC magnets, cryogenics and electronic equipment placed in the IR8. In fact, the LHCb experiment was conceived to work at a much lower luminosity than ATLAS and CMS, implying minor requirements for protection of the LHC elements from the collision debris and therefore a different layout around the interaction point. The luminosity target proposed for the Upgrade II requires to review the layout of the entire insertion region in order to ensure safe operation of the LHC magnets and to mitigate the risk of failure of the electronic devices. The objective of this paper is to provide an overview of the implications of the Upgrade II of LHCb in the experimental cavern and in the tunnel with a focus on the LHCb detector, electronic devices and accelerator magnets

    Therapeutic administration of broadly neutralizing FI6 antibody reveals lack of interaction between human IgG1 and pig Fc receptors

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    Influenza virus infection is a significant global health threat. Because of the lack of cross-protective universal vaccines, short time window during which antivirals are effective and drug resistance, new therapeutic anti-influenza strategies are required. Broadly, cross-protective antibodies that target conserved sites in the hemagglutinin (HA) stem region have been proposed as therapeutic agents. FI6 is the first proven such monoclonal antibody to bind to H1–H16 and is protective in mice and ferrets. Multiple studies have shown that Fc-dependent mechanisms are essential for FI6 in vivo efficacy. Here, we show that therapeutic administration of FI6 either intravenously or by aerosol to pigs did not reduce viral load in nasal swabs or broncho-alveolar lavage, but aerosol delivery of FI6 reduced gross pathology significantly. We demonstrate that pig Fc receptors do not bind human IgG1 and that FI6 did not mediate antibody-dependent cytotoxicity (ADCC) with pig PBMC, confirming that ADCC is an important mechanism of protection by anti-stem antibodies in vivo. Enhanced respiratory disease, which has been associated with pigs with cross-reactive non-neutralizing anti-HA antibodies, did not occur after FI6 administration. Our results also show that in vitro neutralizing antibody responses are not a robust correlate of protection for the control of influenza infection and pathology in a natural host model

    Case report: A novel patient presenting TRIM32-related limb-girdle muscular dystrophy

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    Limb-girdle muscular dystrophy autosomal recessive 8 (LGMDR8) is a rare clinical manifestation caused by the presence of biallelic variants in the TRIM32 gene. We present the clinical, molecular, histopathological, and muscle magnetic resonance findings of a novel 63-years-old LGMDR8 patient of Italian origins, who went undiagnosed for 24 years. Clinical exome sequencing identified two TRIM32 missense variants, c.1181G > A p.(Arg394His) and c.1781G > A p.(Ser594Asp), located in the NHL1 and NHL4 structural domains, respectively, of the TRIM32 protein. We conducted a literature review of the clinical and instrumental data associated to the so far known 26 TRIM32 variants, carried biallelically by 53 LGMDR8 patients reported to date in 20 papers. Our proband's variants were previously identified only in three independent LGMDR8 patients in homozygosis, therefore our case is the first in literature to be described as compound heterozygous for such variants. Our report also provides additional data in support of their pathogenicity, since p.(Arg394His) is currently classified as a variant of uncertain significance, while p.(Ser594Asp) as likely pathogenic. Taken together, these findings might be useful to improve both the genetic counseling and the diagnostic accuracy of this rare neuromuscular condition

    Detector Simulation Challenges for Future Accelerator Experiments

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    Detector simulation is a key component for studies on prospective future high-energy colliders, the design, optimization, testing and operation of particle physics experiments, and the analysis of the data collected to perform physics measurements. This review starts from the current state of the art technology applied to detector simulation in high-energy physics and elaborates on the evolution of software tools developed to address the challenges posed by future accelerator programs beyond the HL-LHC era, into the 2030–2050 period. New accelerator, detector, and computing technologies set the stage for an exercise in how detector simulation will serve the needs of the high-energy physics programs of the mid 21st century, and its potential impact on other research domains

    Prophylactic Activity of Orally Administered FliD-Reactive Monoclonal SIgA Against Campylobacter Infection

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    This work is licensed under a Creative Commons Attribution 4.0 International License.Campylobacter infection is one of the most common causes of bacterial gastroenteritis worldwide and a major global health threat due to the rapid development of antibiotic resistance. Currently, there are no vaccines approved to prevent campylobacteriosis, and rehydration is the main form of therapy. Secretory immunoglobulin A (SIgA) is the main antibody class found in mucous secretions, including human milk, and serves as the first line of defense for the gastrointestinal epithelium against enteric pathogens. In this study, we describe the prophylactic activity of orally delivered recombinant SIgA generated from two human monoclonal antibodies (CAA1 and CCG4) isolated for their reactivity against the flagellar-capping protein FliD, which is essential for bacteria motility and highly conserved across Campylobacter species associated with severe enteritis. In an immunocompetent weaned mouse model, a single oral administration of FliD-reactive SIgA CAA1 or CCG4 at 2 h before infection significantly enhances Campylobacter clearance at early stages post-infection, reducing the levels of inflammation markers associated with epithelial damage and polymorphonuclear (PMN) cells infiltration in the cecum lamina propria. Our data indicate that the prophylactic activity of CAA1 and CCG4 is not only dependent on the specificity to FliD but also on the use of the SIgA format, as the immunoglobulin G (IgG) versions of the same antibodies did not confer a comparable protective effect. Our work emphasizes the potential of FliD as a target for the development of vaccines and supports the concept that orally administered FliD-reactive SIgA can be developed to prevent or mitigate the severity of Campylobacter infections as well as the development of post-infection syndromes.Bill & Melinda Gates foundation (grant: OPP1170883

    Prophylactic and postexposure efficacy of a potent human monoclonal antibody against MERS coronavirus

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    Middle East Respiratory Syndrome coronavirus (MERS-CoV) causes severe respiratory disease with a high mortality rate. There is no licensed vaccine or antiviral for MERS. Here we isolated for the first time, to our knowledge, a potent MERS-CoV–neutralizing antibody from memory B cells of an infected individual. This antibody binds to a novel site on the viral Spike protein, neutralizes by interfering with the binding to the cellular receptor CD26, and is highly effective both in prophylaxis and in therapy in a relevant mouse model. This antibody can be developed for prophylaxis, for postexposure prophylaxis, or for the treatment of severe MERS-CoV infections
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