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Current-driven magnetization decrease in single crystalline ferromagnetic manganese oxide
The electrical and magnetic response to a bias current has been investigated
in a singlecrystalline ferromagnetic manganese oxide
CaMnO . A significant decrease of the magnetization is
observed at the same threshold current where a non-linearity of V-I
characteristics appears. Such a behavior cannot be understood in the framework
of the filamentary picture usually invoked for the non linearity of the other
manganese oxides. Instead, an analogy with spintronic features might be useful
and experimental signatures seem to be in agreement with excitations of spin
waves by an electric current. This provides an example of a bulk system in
which the spin polarized current induces a macroscopic change in the
magnetization.Comment: 3 pages, 4 figure
Hartree-Fock calculations for the ground and first excited states of H2
Hartree-Fock calculation for ground and first excited state of H
Conditional regularity of solutions of the three dimensional Navier-Stokes equations and implications for intermittency
Two unusual time-integral conditional regularity results are presented for
the three-dimensional Navier-Stokes equations. The ideas are based on
-norms of the vorticity, denoted by , and particularly
on , where for . The first result, more appropriate for the unforced case, can be stated
simply : if there exists an for which the integral condition
is satisfied () then no singularity can occur on . The
constant for large . Secondly, for the forced case, by
imposing a critical \textit{lower} bound on , no
singularity can occur in for \textit{large} initial data. Movement
across this critical lower bound shows how solutions can behave intermittently,
in analogy with a relaxation oscillator. Potential singularities that drive
over this critical value can be ruled out whereas
other types cannot.Comment: A frequency was missing in the definition of D_{m} in (I5) v3. 11
pages, 1 figur
Coronary artery spasm and non-Q-wave myocardial infarction following intravenous ephedrine in two healthy women under spinal anaesthesia
Vasovagal episodes occur frequently in young healthy patients undergoing venous cannulation and loco-regional anaesthesia. We report two cases of severe coronary vasospasm and non-Qwave infarction in healthy young women after administration of ephedrine for vasovagal symptoms at the onset of spinal anaesthesia. In the light of unopposed vagal predominance predisposing patients to coronary vasospasm, even in young healthy patients, atrophine and not ephedrine should be the first line treatment for bradycardia with or without hypotension under spinal anaesthesi
Hydrology of the surficial aquifer in the Floyd River Basin, Iowa
https://ir.uiowa.edu/igs_wsb/1011/thumbnail.jp
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Hypoimmunogenic Derivatives of Induced Pluripotent Stem Cells Evade Immune Rejection in Fully Immunocompetent Allogeneic Recipients
Metal-to-insulator crossover and pseudogap in single-layer compound BiSrCuO single crystals in high magnetic fields
The in-plane and the out-of-plane
magneto-transport in magnetic fields up to 28 T has been investigated in a
series of high quality, single crystal, hole-doped La-free Bi2201 cuprates for
a wide doping range and over a wide range of temperatures down to 40 mK. With
decreasing hole concentration going from the overdoped (p=0.2) to the
underdoped (p=0.12) regimes, a crossover from a metallic to and insulating
behavior of is observed in the low temperature normal state,
resulting in a disorder induced metal insulator transition. In the zero
temperature limit, the normal state ratio of the
heavily underdoped samples in pure Bi2201 shows an anisotropic 3D behavior, in
striking contrast with that observed in La-doped Bi2201 and LSCO systems. Our
data strongly support that that the negative out-of-plane magnetoresistance is
largely governed by interlayer conduction of quasiparticles in the
superconducting state, accompanied by a small contribution of normal state
transport associated with the field dependent pseudogap. Both in the optimal
and overdoped regimes, the semiconducting behavior of persists even
for magnetic fields above the pseudogap closing field . The method
suggested by Shibauchi \textit{et al.} (Phys. Rev. Lett. \textbf{86}, 5763,
(2001)) for evaluating is unsuccessful for both under- and overdoped
Bi2201 samples. Our findings suggest that the normal state pseudogap is not
always a precursor of superconductivity.Comment: 11 pages, 8 figures, published in PRB Nov 200
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