281 research outputs found

    Gaussian stationary processes over graphs, general frame and maximum likelihood identification

    Get PDF
    In this paper, using spectral theory of Hilbertian operators, we study ARMA Gaussian processes indexed by graphs. We extend Whittle maximum likelihood estimation of the parameters for the corresponding spectral density and show their asymptotic optimality

    E. coli K 99+ infection in calves : protective eff ect of smectite

    Get PDF
    Chez les veaux nouveau-nés, l’infection colibacillaire est responsable de gastro-entérite. Douze heures après l’inoculation d’une souche d’E. coli entéro- toxinogène apparaît la diarrhée puis la déshydratation. L’observation ultra- structurale en microscopic électronique à balayage confirme l’effet pathogène du colibacille qui se manifeste par un allongement des villosités intestinales et une altération des entérocytes. Si les veaux reçoivent en même temps que l’inoculum de la smectite à la dose de 500 m g/kg/4 jours, les signes diarrhéiques sont réduits et sans déshydratation. Ces résultats sont confirmés par les mesures de concentrations plasma- tiques des ions Na+, K+, et de l’acide lactique. Par ailleurs, d’un point de vue ultrastructural, les villosités intestinales gardent un aspect normal. En conclusion, la smectite, argile colloïdale, par ses propriétés d’adsorp- tion du colibacille et ses effets sur le mucus protège la muqueuse iléale des effets pathogènes des colibacilles entérotoxinogènes.Nouvelles de nos Organisation

    A New syndrome of the charolais neonatal calf : paralysis in gastroenteritis

    Get PDF
    Un nouveau syndrome diarrhéique associé à des symptômes nerveux généraux et locomoteurs a été identifié en Charoláis chez des veaux de moins de deux semaines d’âge. Il présente des analogies avec une maladie congénitale liée à un trouble du métabolisme des aminoacides ramifiés mais le rôle plus probable de colibacilles produisant des cytotoxines neu rotoxiques est à confirmer.A new diarrheic syndrome associated with general and locomotor nervous symptoms has been identified in the charoláis area in calves under 2 weeks of age. This condition presents some similarities to a congenital disease related to impaired branched-aminoacid metabolism, but the more probable involvment of neurotoxic cytotoxin-producing E. Coli bacteria remains to be confirmed

    A Kriging procedure for processes indexed by graphs

    Get PDF
    International audienceWe provide a new kriging procedure of processes on graphs. Based on the construction of Gaussian random processes indexed by graphs, we extend to this framework the usual linear prediction method for spatial random fields, known as kriging. We provide the expression of the estimator of such a random field at unobserved locations as well as a control for the prediction error

    Recherche par une technique d'hémagglutination passive des traces sérologiques des principaux virus respiratoires des bovins et de Chlamydia psittaci dans un échantillon de la population des bovidés du Togo

    Get PDF
    D'après les résultats obtenus par la technique d'hémagglutination passive, le principal virus respiratoire des bovins du Togo est celui de la rhinotrachéite infectieuse bovine. Les autres virus et Chlamydia psittaci semblent avoir moins d'importanc

    The role of pasteurella spp and of Mycoplasma bovis in respiratory diseases in young cattle

    Get PDF
    Lors des essais terrains d’un traitement antibiotique chez des veaux d’éle vage atteints de maladies respiratoires, la flore trachéobronchique a été inven toriée à différentes périodes : à l’arrivée, avant traitement et après guérison. Le rôle de l’association synergique Mycoplasma bovis - Pasteurella haemoly- tica Al apparaît clairement. Les conditions d’élevage et la participation de certains virus (RSV) sont encore des éléments importants de la pathogénèse et du pronostic des bronchopneumonies infectieuses enzootiques.When we tried an antibiotic treatment on clinical trials on weaner calves with respiratory diseases, tracheobronchial flora was examined at different moments : on the day of the arrival, before treatment and after recovery. The role of the synergistic association of Mycoplasma bovis / Pasteurella haemo- lytica A1 in the development of troubles appears to be confirmed. Bad breeding conditions and the participation of a virus (RSV) are important components of pathogenesis and prognosis of bovine Endemic Infectious Broncho pneumonia

    SPIRIT and CONSORT extensions for early phase dose-finding clinical trials:the DEFINE (DosE FIndiNg Extensions) study protocol

    Get PDF
    Introduction Early phase dose-finding (EPDF) studies are critical for the development of new treatments, directly influencing whether compounds or interventions can be investigated in further trials to confirm their safety and efficacy. There exists guidance for clinical trial protocols and reporting of completed trials in the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) 2013 and CONsolidated Standards Of Reporting Randomised Trials (CONSORT) 2010 statements. However, neither the original statements nor their extensions adequately cover the specific features of EPDF trials. The DEFINE (DosE-FIndiNg Extensions) study aims to enhance transparency, completeness, reproducibility and interpretation of EPDF trial protocols (SPIRIT-DEFINE) and their reports once completed (CONSORT-DEFINE), across all disease areas, building on the original SPIRIT 2013 and CONSORT 2010 statements. Methods and analysis A methodological review of published EPDF trials will be conducted to identify features and deficiencies in reporting and inform the initial generation of the candidate items. The early draft checklists will be enriched through a review of published and grey literature, real-world examples analysis, citation and reference searches and consultation with international experts, including regulators and journal editors. Development of CONSORT-DEFINE commenced in March 2021, followed by SPIRIT-DEFINE from January 2022. A modified Delphi process, involving worldwide, multidisciplinary and cross-sector key stakeholders, will be run to refine the checklists. An international consensus meeting in autumn 2022 will finalise the list of items to be included in both guidance extensions. Ethics and dissemination This project was approved by ICR’s Committee for Clinical Research. The Health Research Authority confirmed Research Ethics Approval is not required. The dissemination strategy aims to maximise guideline awareness and uptake, including but not limited to dissemination in stakeholder meetings, conferences, peer-reviewed publications and on the EQUATOR Network and DEFINE study websites

    Time-dependent visibility modelling of a relativistic jet in the X-ray binary MAXI J1803-298

    Get PDF
    Tracking the motions of transient jets launched by low-mass X-ray binaries (LMXBs) is critical for determining the moment of jet ejection, and identifying any corresponding signatures in the accretion flow. However, these jets are often highly variable and can travel across the resolution element of an image within a single observation, violating a fundamental assumption of aperture synthesis. We present a novel approach in which we directly fit a single time-dependent model to the full set of interferometer visibilities, where we explicitly parameterise the motion and flux density variability of the emission components, to minimise the number of free parameters in the fit, while leveraging information from the full observation. This technique allows us to detect and characterize faint, fast-moving sources, for which the standard time binning technique is inadequate. We validate our technique with synthetic observations, before applying it to three Very Long Baseline Array (VLBA) observations of the black hole candidate LMXB MAXI J1803-298 during its 2021 outburst. We measured the proper motion of a discrete jet component to be 1.37±0.141.37\pm0.14 mas/hr, and thus we infer an ejection date of MJD 59348.08−0.06+0.0559348.08_{-0.06}^{+0.05}, which occurs just after the peak of a radio flare observed by the Australia Telescope Compact Array (ATCA) and the Atacama Large Millimeter/Sub-Millimeter Array (ALMA), while MAXI J1803-298 was in the intermediate state. Further development of these new VLBI analysis techniques will lead to more precise measurements of jet ejection dates, which, combined with dense, simultaneous multi-wavelength monitoring, will allow for clearer identification of jet ejection signatures in the accretion flow.Comment: 15 pages, 9 figures, 4 tables; Accepted for publication in MNRA
    • …
    corecore