1,497 research outputs found
Cocirculation of Hajj and non-Hajj strains among serogroup W meningococci in Italy, 2000 to 2016
In Italy, B and C are the predominant serogroups among meningococci causing invasive diseases. Nevertheless, in the period from 2013 to 2016, an increase in serogroup W Neisseria meningitidis (MenW) was observed. This study intends to define the main characteristics of 63 MenW isolates responsible of invasive meningococcal disease (IMD) in Italy from 2000 to 2016. We performed whole genome sequencing on bacterial isolates or single gene sequencing on culturenegative samples to evaluate molecular heterogeneity. Our main finding was the cocirculation of the Hajj and the South American sublineages belonging to MenW/ clonal complex (cc)11, which gradually surpassed the MenW/cc22 in Italy. All MenW/cc11 isolates were fully susceptible to cefotaxime, ceftriaxone, ciprofloxacin, penicillin G and rifampicin. We identified the fulllength NadA protein variant 2/3, present in all the MenW/cc11. We also identified the fHbp variant 1, which we found exclusively in the MenW/cc11/Hajj sublineage. Concern about the epidemic potential of MenW/cc11 has increased worldwide since the year 2000. Continued surveillance, supported by genomic characterisation, allows high-resolution tracking of pathogen dissemination and the detection of epidemicassociated strains
Density determinations in heavy ion collisions
The experimental determination of freeze-out temperatures and densities from
the yields of light elements emitted in heavy ion collisions is discussed.
Results from different experimental approaches are compared with those of model
calculations carried out with and without the inclusion of medium effects.
Medium effects become of relevance for baryon densities above fm. A quantum statistical (QS) model incorporating medium
effects is in good agreement with the experimentally derived results at higher
densities. A densitometer based on calculated chemical equilibrium constants is
proposed.Comment: 5 pages, 3 figure
Interleukin-1 and interleukin-2 control granulocyte- and granulocyte-macrophage colony-stimulating factor gene expression and cell proliferation in cultured acute myeloblastic leukemia.
Mortality and cause of death among psychiatric patients: a 20-year case-register study in an area with a community-based system of care
Critical behavior of the isotope yield distributions in the Multifragmentation Regime of Heavy Ion Reactions
Isotope yields have been analyzed within the framework of a Modified Fisher
Model to study the power law yield distribution of isotopes in the
multifragmentation regime. Using the ratio of the mass dependent symmetry
energy coefficient relative to the temperature, , extracted in
previous work and that of the pairing term, , extracted from this
work, and assuming that both reflect secondary decay processes, the
experimentally observed isotope yields have been corrected for these effects.
For a given I = N - Z value, the corrected yields of isotopes relative to the
yield of show a power law distribution, , in the mass range of and the distributions are
almost identical for the different reactions studied. The observed power law
distributions change systematically when I of the isotopes changes and the
extracted value decreases from 3.9 to 1.0 as I increases from -1 to 3.
These observations are well reproduced by a simple de-excitation model, which
the power law distribution of the primary isotopes is determined to
, suggesting that the disassembling system at the
time of the fragment formation is indeed at or very near the critical point.Comment: 5 pages, 5 figure
The Isospin Dependence Of The Nuclear Equation Of State Near The Critical Point
We discuss experimental evidence for a nuclear phase transition driven by the
different concentration of neutrons to protons. Different ratios of the neutron
to proton concentrations lead to different critical points for the phase
transition. This is analogous to the phase transitions occurring in 4He-3He
liquid mixtures. We present experimental results which reveal the N/A (or Z/A)
dependence of the phase transition and discuss possible implications of these
observations in terms of the Landau Free Energy description of critical
phenomena.Comment: 14 pages, 18 figure
Experimental study of fusion neutron and proton yields produced by petawatt-laser-irradiated D2-3He or CD4-3He clustering gases
We report on experiments in which the Texas Petawatt laser irradiated a
mixture of deuterium or deuterated methane clusters and helium-3 gas,
generating three types of nuclear fusion reactions: D(d, 3He)n, D(d, t)p and
3He(d, p)4He. We measured the yields of fusion neutrons and protons from these
reactions and found them to agree with yields based on a simple cylindrical
plasma model using known cross sections and measured plasma parameters. Within
our measurement errors, the fusion products were isotropically distributed.
Plasma temperatures, important for the cross sections, were determined by two
independent methods: (1) deuterium ion time-of-flight, and (2) utilizing the
ratio of neutron yield to proton yield from D(d, 3He)n and 3He(d, p)4He
reactions, respectively. This experiment produced the highest ion temperature
ever achieved with laser-irradiated deuterium clusters.Comment: 16 pages, 6 figure
Repeated infusions of donor-derived cytokine-induced killer cells in patients relapsing after allogeneic stem cell transplantation: a phase I study
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Temperature measurements of fusion plasmas produced by petawatt laser-irradiated D2-3He or CD4-3He clustering gases
Two different methods have been employed to determine the plasma temperature
in a laser-cluster fusion experiment on the Texas Petawatt laser. In the first,
the temperature was derived from time-of-flight data of deuterium ions ejected
from exploding D2 or CD4 clusters. In the second, the temperature was measured
from the ratio of the rates of two different nuclear fusion reactions occurring
in the plasma at the same time: D(d, 3He)n and 3He(d, p)4He. The temperatures
determined by these two methods agree well, which indicates that: i) The ion
energy distribution is not significantly distorted when ions travel in the
disassembling plasma; ii) The kinetic energy of deuterium ions, especially the
hottest part responsible for nuclear fusion, is well described by a
near-Maxwellian distribution.Comment: 13 pages, 4 figure
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