2,521 research outputs found

    Using environmental DNA for detection of Batrachochytrium salamandrivorans in natural water

    Get PDF
    Rapid, early, and reliable detection of invasive pathogenic microorganisms is essential in order to either predict or delineate an outbreak, and monitor appropriate mitigation measures. The chytrid fungus Batrachochytrium salamandrivorans is expanding in Europe, and infection with this fungus may cause massive mortality in urodelans (salamanders and newts). In this study, we designed and validated species‐specific primers and a probe for detection of B. salamandrivorans in water. In a garden pond in close proximity to the B. salamandrivorans index site in the Netherlands, B. salamandrivorans‐infected newts had been detected in 2015 and have been monitored since. In 2016 and 2017, no B. salamandrivorans was detected at this site, but in 2018 B. salamandrivorans flared up in this isolated pond which allowed validation of the technique in situ. We here present the development of an environmental DNA technique that successfully detects B. salamandrivorans DNA in natural waterbodies even at low concentrations. This technique may be further validated to play a role in B. salamandrivorans range delineation and surveillance in both natural waterbodies and in captive collections

    Three-body continuum-discretized coupled-channel calculations for 6 He scattering from heavy nuclei

    Get PDF
    ata for scattering of 6He from 197Au, 208Pb, and 209Bi targets at low energies were consistently analyzed by use of the continuum-discretized coupled-channels method and the dineutron model of the projectile. A very good description of the experimental data was obtained with the strength of the dipole couplings reduced by 50%. We find that the dipole couplings are responsible for the suppression of the Coulomb rainbow and that the quadrupole couplings must be included in the calculations in order to obtain good agreement with the elastic-scattering data at more backward angles.Ministerio de Ciencia y TecnologĂ­a FPA2003-05958 FPA2005-0446

    Multi-neutron transfer in 8^{8}He induced reactions near the Coulomb barrier

    Get PDF
    The measured inclusive 6^6He and 4^4He production cross sections of G. Marqu{\'i}nez-Dur{\'a}n {\em et al.}, Phys.\ Rev.\ C {\bf 98}, 034615 (2018) are reexamined and the conclusions concerning the relative importance of 1n and 2n transfer to the production of 6^6He arising from the interaction of a 22 MeV 8^8He beam with a 208^{208}Pb target revised. A consideration of the kinematics of the 2n-stripping reaction when compared with the measured 6^6He total energy versus angle spectrum places strict limits on the allowed excitation energy of the 210^{210}Pb residual, so constraining distorted wave Born approximation calculations that the contribution of the 2n stripping process to the inclusive 6^6He production can only be relatively small. It is therefore concluded that the dominant 6^6He production mechanism must be 1n stripping followed by decay of the 7^7He ejectile. Based on this result we present strong arguments in favor of direct, one step four-neutron (4n) stripping as the main mechanism for 4^4He production.Comment: 7 pages, 2 figure

    GENESIS OF HYPOXIC CONDITIONS IN PATIENTS WITH OPEN FRACTURES OF SHIN BONES IN DYNAMICS OF TREATMENT BY ILIZAROV’S METHOD

    Get PDF
    Indices of energy metabolism in blood serum and partial oxygen and. carbon dioxide pressure in the injured limb tissues were studied in dynamics in 32 patients with open leg fractures (Kaplan-Markova type I-II B, C) during their treatment with the Ilizarov method. It was revealed that circulatory hypoxia, complicated by hemic hypoxia and followed by tissue hypoxia developed sequentially in the tissues of the injured limb segment in the posttraumatic period

    Influence of single-neutron stripping on near-barrier <sup>6</sup>He+<sup>208</sup>Pb and <sup>8</sup>He+<sup>208</sup>Pb elastic scattering

    Get PDF
    The influence of single-neutron stripping on the near-barrier elastic scattering angular distributions for the 6,8He+208Pb systems is investigated through coupled reaction channels (CRC) calculations fitting recently published data to explore the differences in the absorptive potential found in the scattering of these two neutron-rich nuclei. The inclusion of the coupling reduces the elastic cross section in the Coulomb-nuclear interference region for 8He scattering, whereas for 6He its major impact is on the large-angle elastic scattering. The real and imaginary dynamic polarization potentials are obtained by inverting the CRC elastic scattering S-matrix elements. These show that the main absorptive features occur between 11 and 12 fm for both projectiles, while the attractive features are separated by about 1 fm, with their main structures occurring at 10.5 fm for 6He and 11.5 fm for 8He

    Elastic Scattering of 6He on Heavy Targets at Coulomb Barrier Energies

    Get PDF
    Elastic cross sections for the scattering of 6He projectiles by 208Pb at 27 MeV have been studied. The data have been analyzed within the framework of the Optical Model using Saxon–Woods phenomenological form factors for both the real and imaginary parts of the nuclear potential. The elastic scattering data suggests the presence of a long range absorption mechanisms which might be related to the halo structure of 6He.Ministerio Ciencia y Tecnología FPA2002-04181- C04-04 y FPA2000-1592-C03-0

    Reorientation and coupling effects in polarized heavy ion fusion

    Get PDF
    A simple model to understand the reaction mechanisms in the fusion of polarized heavy ions based on tidal symmetry, the sudden approximation and barrier penetration is presented. The model is applied to 23Na+208Pb. The effect of the ground state reorientation and the coupling to rotational states is studied. Enhancement of the sub-barrier fusion cross sections and the fusion J-moments just above the barrier are found. The polarization of the projectile affects strongly the fusion around and below the Coulomb barrier.DirecciĂłn General de Investigaciones CientĂ­ficas y TĂ©cnicas PB89-063

    Cytokine Reduction in the Treatment of Joint Conditions

    Get PDF
    The destruction of joints caused by rheumatoid arthritis and osteoarthritis is characterized by an imbalance of enzyme catalysed cartilage breakdown and regeneration. A complex cytokine network perpetuates joint conditions by direct regulation of metalloproteases, by indirect recruitment of cells that secrete degradative enzymes, and by inhibition of reparative processes. The destructive action of cytokines such as interleukin-1, interleukin-6 and tumour necrosis factor-α can be modulated at multiple points associated either with cytokine production or with cytokine action. Potential agents for cytokine reduction include selective anti-cytokine antibodies, anticytokine receptor antibodies, cytokine receptor antagonist proteins, and soluble and chimeric cytokine receptor molecules. Pharmacologic regulation of IL-1 and TNFα remain primary targets for treatment of arthritis, and results of early clinical trials are promising. However, the results of long-term clinical trials will be required to support the value of anti-cytokine therapy in treatment of arthritis
    • 

    corecore