5,101 research outputs found

    Features of the opportunistic behaviour of the marine bacterium marinobacter algicola in the microalga ostreococcus tauri phycosphere

    Get PDF
    Although interactions between microalgae and bacteria are observed in both natural environment and the laboratory, the modalities of coexistence of bacteria inside microalgae phycospheres in laboratory cultures are mostly unknown. Here, we focused on well-controlled cultures of the model green picoalga Ostreococcus tauri and the most abundant member of its phycosphere, Marinobacter algicola. The prevalence of M. algicola in O. tauri cultures raises questions about how this bacterium maintains itself under laboratory conditions in the microalga culture. The results showed that M. algicola did not promote O. tauri growth in the absence of vitamin B12 while M. algicola depended on O. tauri to grow in synthetic medium, most likely to obtain organic carbon sources provided by the microalgae. M. algicola grew on a range of lipids, including triacylglycerols that are known to be produced by O. tauri in culture during abiotic stress. Genomic screening revealed the absence of genes of two particular modes of quorum-sensing in Marinobacter genomes which refutes the idea that these bacterial communication systems operate in this genus. To date, the ‘opportunistic’ behaviour of M. algicola in the laboratory is limited to several phytoplanktonic species including Chlorophyta such as O. tauri. This would indicate a preferential occurrence of M. algicola in association with these specific microalgae under optimum laboratory conditions

    Precision measurement of the neutrino velocity with the ICARUS detector in the CNGS beam

    Get PDF
    During May 2012, the CERN-CNGS neutrino beam has been operated for two weeks for a total of 1.8 10^17 pot in bunched mode, with a 3 ns narrow width proton beam bunches, separated by 100 ns. This tightly bunched beam structure allows a very accurate time of flight measurement of neutrinos from CERN to LNGS on an event-by-event basis. Both the ICARUS-T600 PMT-DAQ and the CERN-LNGS timing synchronization have been substantially improved for this campaign, taking ad-vantage of additional independent GPS receivers, both at CERN and LNGS as well as of the deployment of the "White Rabbit" protocol both at CERN and LNGS. The ICARUS-T600 detector has collected 25 beam-associated events; the corresponding time of flight has been accurately evaluated, using all different time synchronization paths. The measured neutrino time of flight is compatible with the arrival of all events with speed equivalent to the one of light: the difference between the expected value based on the speed of light and the measured value is tof_c - tof_nu = (0.10 \pm 0.67stat. \pm 2.39syst.) ns. This result is in agreement with the value previously reported by the ICARUS collaboration, tof_c - tof_nu = (0.3 \pm 4.9stat. \pm 9.0syst.) ns, but with improved statistical and systematic errors.Comment: 21 pages, 13 figures, 1 tabl

    Preserving mobility in older adults with physical frailty and sarcopenia: Opportunities, challenges, and recommendations for physical activity interventions

    Get PDF
    One of the most widely conserved hallmarks of aging is a decline in functional capabilities. Mobility loss is particularly burdensome due to its association with negative health outcomes, loss of independence and disability, and the heavy impact on quality of life. Recently, a new condition, physical frailty and sarcopenia, has been proposed to define a critical stage in the disabling cascade. Physical frailty and sarcopenia are characterized by weakness, slowness, and reduced muscle mass, yet with preserved ability to move indepen-dently. One of the strategies that have shown some benefits in combatting mobility loss and its consequences for older adults is physical activity. Here, we describe the opportunities and challenges for the development of physical activity interventions in people with physical frailty and sarcopenia. The aim of this article is to review age-related physio(patho)logical changes that impact mobility in old age and to provide recommendations and procedures in accordance with the available literature

    Linking nationwide health and social registry data to inform the policy for Tuberculosis contact tracing in Brazil.

    Get PDF
    Objectives Mitigating the socioeconomic determinants of Tuberculosis (TB) and systematic screening of contacts and high-risk groups are targets of The World Health Organization (WHO) End TB Strategy by 2035. Our aim was to link socioeconomic information to TB datasets to inform policy makers in Brazil and contribute to addressing current challenges. Approach Following a signed technical cooperation agreement with the Ministry of Health (MoH), we linked nationwide data on 1.405.682 registries of TB diagnosed between 2004 and 2019 in Brazil to 131.697.800 demographic and socioeconomic registries from the 100 Million Brazilian Cohort (2001-2018) previously linked to nationwide mortality data. We established close links with TB managers to understand the database, clean and deduplicate registries and to analyse the data. We took advantage of the data structure, to set up a cohort of household contacts of TB patients and produce estimates of TB incidence by subgroups of demographic and socioeconomic characteristics. Results The interaction of the MoH was effective and facilitated by a robust TB Programme in the country. 567.999 (40,41%) TB cases were linked to the 100 Million Brazilian Cohort with high specificity (93.6%) and sensitivity (94.6%). Using family identifiers, we established the first TB case within a family unit (i.e., primary case) and followed their household contacts up to 15 years. We found the TB incidence among household contacts to be 427.8/100.000 person-years (95%CI 419.1-436.8). In the first year following the identification of the primary case, there was higher cumulative incidence among household contacts under 5 years of age, which was followed by a plateau of cases in this age group. Cummulative incidence in the other age groups presented a constant increase over time. Conclusion The close collaboration with the MoH, the development of an effective linkage algorithm and the availability of large socioeconomic data allowed for a unique analysis of the high incidence of TB among household contacts. Findings reinforce need for constant dialogue among stakeholders to strengthen case detection by primary health care

    Measurement of CNGS muon neutrino speed with Borexino

    Get PDF
    We have measured the speed of muon neutrinos with the Borexino detector using short-bunch CNGS beams. The final result for the difference in time-of-flight between a =17 GeV muon neutrino and a particle moving at the speed of light in vacuum is {\delta}t = 0.8 \pm 0.7stat \pm 2.9sys ns, well consistent with zero.Comment: 6 pages, 5 figure

    BepiColombo’s Cruise Phase: Unique Opportunity for Synergistic Observations

    Get PDF
    The investigation of multi-spacecraft coordinated observations during the cruise phase of BepiColombo (ESA/JAXA) are reported, with a particular emphasis on the recently launched missions, Solar Orbiter (ESA/NASA) and Parker Solar Probe (NASA). Despite some payload constraints, many instruments onboard BepiColombo are operating during its cruise phase simultaneously covering a wide range of heliocentric distances (0.28 AU–0.5 AU). Hence, the various spacecraft configurations and the combined in-situ and remote sensing measurements from the different spacecraft, offer unique opportunities for BepiColombo to be part of these unprecedented multipoint synergistic observations and for potential scientific studies in the inner heliosphere, even before its orbit insertion around Mercury in December 2025. The main goal of this report is to present the coordinated observation opportunities during the cruise phase of BepiColombo (excluding the planetary flybys). We summarize the identified science topics, the operational instruments, the method we have used to identify the windows of opportunity and discuss the planning of joint observations in the future

    Highlights from the Pierre Auger Observatory

    Full text link
    The Pierre Auger Observatory is the world's largest cosmic ray observatory. Our current exposure reaches nearly 40,000 km2^2 str and provides us with an unprecedented quality data set. The performance and stability of the detectors and their enhancements are described. Data analyses have led to a number of major breakthroughs. Among these we discuss the energy spectrum and the searches for large-scale anisotropies. We present analyses of our Xmax_{max} data and show how it can be interpreted in terms of mass composition. We also describe some new analyses that extract mass sensitive parameters from the 100% duty cycle SD data. A coherent interpretation of all these recent results opens new directions. The consequences regarding the cosmic ray composition and the properties of UHECR sources are briefly discussed.Comment: 9 pages, 12 figures, talk given at the 33rd International Cosmic Ray Conference, Rio de Janeiro 201

    First Report of Sylvatic DENV-2-Associated Dengue Hemorrhagic Fever in West Africa

    Get PDF
    Dengue virus (DENV) circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF) with thrombocytopenia (13000/”l), a raised hematocrit (32% above baseline) and mucosal bleeding in a 27-year-old male returning to Spain in November 2009 after visiting his home country Guinea Bissau. Sylvatic DENV-2 West African lineage was isolated from blood and sera. This is the first case of DHF associated with sylvatic DENV-2 in Africa and the second case worldwide of DHF caused by a sylvatic strain

    A search for point sources of EeV photons

    Full text link
    Measurements of air showers made using the hybrid technique developed with the fluorescence and surface detectors of the Pierre Auger Observatory allow a sensitive search for point sources of EeV photons anywhere in the exposed sky. A multivariate analysis reduces the background of hadronic cosmic rays. The search is sensitive to a declination band from -85{\deg} to +20{\deg}, in an energy range from 10^17.3 eV to 10^18.5 eV. No photon point source has been detected. An upper limit on the photon flux has been derived for every direction. The mean value of the energy flux limit that results from this, assuming a photon spectral index of -2, is 0.06 eV cm^-2 s^-1, and no celestial direction exceeds 0.25 eV cm^-2 s^-1. These upper limits constrain scenarios in which EeV cosmic ray protons are emitted by non-transient sources in the Galaxy.Comment: 28 pages, 10 figures, accepted for publication in The Astrophysical Journa
    • 

    corecore