2,257 research outputs found
Management of von Willebrand disease type 3 during pregnancy - 2 cases reports.
BACKGROUND:
von Willebrand disease type 3, is an extremely rare condition. It can be severe and potentially life-threatening, particularly in pregnant women during labor and subsequently during early puerperium. Due to its rarity, there is no optimal treatment/management during pregnancy.
CASE:
We describe two cases of pregnant women with von Willebrand disease type 3, and its successful surveillance and treatment with Haemate P FVIII (human plasma-derived von Willebrand Factor-ristocetin co-factor associated with human coagulation factor VIII), during pregnancy, partum and puerperium.
CONCLUSIONS:
Daily prophylaxis with Haemate P FVIII in women with von Willebrand disease type 3, starting 2 hours before caesarean section until the 7th day of puerperium, associated with close analytical and clinical surveillance seems to be a safe clinical option
Spin pseudogap in Ni-doped SrCuO2
The S=1/2 spin chain material SrCuO2 doped with 1% S=1 Ni-impurities is
studied by inelastic neutron scattering. At low temperatures, the spectrum
shows a pseudogap \Delta ~ 8 meV, absent in the parent compound, and not
related to any structural phase transition. The pseudogap is shown to be a
generic feature of quantum spin chains with dilute defects. A simple model
based on this idea quantitatively accounts for the exprimental data measured in
the temperature range 2-300 K, and allows to represent the momentum-integrated
dynamic structure factor in a universal scaling form.Comment: 5 pages, 3 figure
Full spin switch effect for the superconducting current in a superconductor/ferromagnet thin film heterostructure
Superconductor/ferromagnet (S/F) proximity effect theory predicts that the
superconducting critical temperature of the F1/F2/S or F1/S/F2 trilayers for
the parallel orientation of the F1 and F2 magnetizations is smaller than for
the antiparallel one. This suggests a possibility of a controlled switching
between the superconducting and normal states in the S layer. Here, using the
spin switch design F1/F2/S theoretically proposed by Oh et al. [Appl. Phys.
Lett. 71, 2376 (1997)], that comprises a ferromagnetic bilayer separated by a
non-magnetic metallic spacer layer as a ferromagnetic component, and an
ordinary superconductor as the second interface component, we have successfully
realized a full spin switch effect for the superconducting current.Comment: 5 pages, 4 figure
Experimental Analysis of the Laser-Induced Instruction Skip Fault Model
International audienceMicrocontrollers storing valuable data or using security functions are vulnerable to fault injection attacks. Among the various types of faults, instruction skips induced at runtime proved to be effective against identification routines or encryption algorithms. Several research works assessed a fault model that consists in a single instruction skip, i.e. the ability to prevent one chosen instruction in a program from being executed. This assessment is used to design countermeasures able to withstand a single instruction skip. We question this fault model on experimental basis and report the possibility to induce with a laser an arbitrary number of instruction skips. This ability to erase entire sections of a firmware has strong implications regarding the design of counter- measures
The Effect of Coherent Structures on Stochastic Acceleration in MHD Turbulence
We investigate the influence of coherent structures on particle acceleration
in the strongly turbulent solar corona. By randomizing the Fourier phases of a
pseudo-spectral simulation of isotropic MHD turbulence (Re ), and
tracing collisionless test protons in both the exact-MHD and phase-randomized
fields, it is found that the phase correlations enhance the acceleration
efficiency during the first adiabatic stage of the acceleration process. The
underlying physical mechanism is identified as the dynamical MHD alignment of
the magnetic field with the electric current, which favours parallel
(resistive) electric fields responsible for initial injection. Conversely, the
alignment of the magnetic field with the bulk velocity weakens the acceleration
by convective electric fields - \bfu \times \bfb at a non-adiabatic stage of
the acceleration process. We point out that non-physical parallel electric
fields in random-phase turbulence proxies lead to artificial acceleration, and
that the dynamical MHD alignment can be taken into account on the level of the
joint two-point function of the magnetic and electric fields, and is therefore
amenable to Fokker-Planck descriptions of stochastic acceleration.Comment: accepted for publication in Ap
The incidence of AGN in galaxies with different stellar population ages
It has been argued that recycled gas from stellar mass loss in galaxies might
serve as an important fuelling source for black holes (BHs) in their centers.
Utilizing spectroscopic samples of galaxies from the Sloan Digital Sky Survey
(SDSS) at and the Large Early Galaxy Astrophysics Census (LEGA-C)
survey at that have X-ray coverage from XMM-Newton or Chandra, we
test this stellar mass loss fuelling scenario by investigating how AGN activity
and BH growth vary with the break strength at 4000 ,
(which is closely related to the age of stellar populations), as younger
galaxies are considered to have higher stellar mass loss rates. We found that
when controlling for host-galaxy properties, the fraction of log / > 32 (which roughly corresponds to Eddington ratios %)
AGN and sample-averaged black hole accretion rate ()
decrease with among 1.9 galaxies,
suggesting a higher level of AGN activity among younger galaxies, which
supports the stellar mass loss fuelling scenario. For the oldest and most
massive galaxies at , this decreasing trend is not present anymore.
We found that, among these most massive galaxies at low redshift, the fraction
of low specific-accretion-rate (31 log / 32) AGNs
increases with , which may be associated with additional
fuelling from hot halo gas and/or enhanced accretion capability.Comment: 24 pages, 28 figures. Accepted for publication in MNRA
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