665 research outputs found
Infrared properties of exotic superconductors
The infrared spectra of the non-traditional superconductors share certain
common features. The lack of a gap signature at and the residual
conductivity are the consequence of a d-wave order parameter. The high
materials, the organic conductors and the heavy Fermion materials have a strong
mid-infrared absorption band which can be interpreted as strong coupling of the
carriers to electronic degrees of freedom which leads to a breakdown of the
Fermi liquid picture. The cuprates and the organic charge transfer salts are
unique in possessing an intrinsic low dimensionality. The charge transport
normal to the highly conducting direction is incoherent down to the lowest
temperatures and frequencies.Comment: 10 pages 11 figures, From the proceedings of the First Euroconference
on Anomalous Complex Superconductors, Heraklion, Crete. Sept 1998, to be
published in Physica
Vortex-antivortex wavefunction of a degenerate quantum gas
A mechanism of a pinning of the quantized matter wave vortices by optical
vortices in a specially arranged optical dipole traps is discussed. The
vortex-antivortex optical arrays of rectangular symmetry are shown to transfer
angular orbital momentum and form the "antiferromagnet"-like matter waves. The
separable Hamiltonian for matter waves in pancake trapping geometry is proposed
and 3D-wavefunction is factorized in a product of wavefunctions of the 1D
harmonic oscillator and 2D vortex-antivortex quantum state. The 2D
wavefunction's phase gradient field associated via Madelung transform with the
field of classical velocities forms labyrinth-like structure. The macroscopic
quantum state composed of periodically spaced counter-rotating BEC superfluid
vortices has zero angular momentum and nonzero rotational energy.Comment: 11 pages, 5 figure
Serosal complications of single-agent low-dose methotrexate used in gestational trophoblastic diseases: first reported case of methotrexate-induced peritonitis
Methotrexate (MTX) is a folate antagonist widely used both as an anticancer drug and as an immunosupressant. Administration of an 8-day methotrexate and folinic acid regime may be associated with pleuritic chest pain and pneumonitis. We have reviewed the toxicity seen in 168 consecutive patients treated with low-dose MTX for persistent trophoblastic disease. Twenty-five per cent of patients developed serosal symptoms, pleurisy was the commonest complaint. The majority of patients had mild to moderate symptoms which were controlled with simple analgesia and did not necessitate a change in treatment; 11.9% had severe symptoms which necessitated a change in treatment. One patient developed a pericardial effusion and a second patient developed severe reversible peritoneal irritation. The possible aetiology and pathophysiology of methotrexate-induced serosal toxicity is discussed. © 1999 Cancer Research Campaig
Active Adenoviral Vascular Penetration by Targeted Formation of Heterocellular Endothelial–epithelial Syncytia
The endothelium imposes a structural barrier to the extravasation of systemically delivered oncolytic adenovirus (Ad). Here, we introduced a transendothelial route of delivery in order to increase tumor accumulation of virus particles (vp) beyond that resulting from convection-dependent extravasation alone. This was achieved by engineering an Ad encoding a syncytium-forming protein, gibbon ape leukemia virus (GALV) fusogenic membrane glycoprotein (FMG). The expression of GALV was regulated by a hybrid viral enhancer-human promoter construct comprising the human cytomegalovirus (CMV) immediate-early enhancer and the minimal human endothelial receptor tyrosine kinase promoter (“eTie1”). Endothelial cell-selectivity of the resulting Ad-eTie1-GALV vector was demonstrated by measuring GALV mRNA transcript levels. Furthermore, Ad-eTie1-GALV selectively induced fusion between infected endothelial cells and uninfected epithelial cells in vitro and in vivo, allowing transendothelial virus penetration. Heterofusion of infected endothelium to human embryonic kidney 293 (HEK 293) cells, in mixed in vitro cultures or in murine xenograft models, permitted fusion-dependent transactivation of the replication-deficient Ad-eTie1-GALV, due to enabled access to viral E1 proteins derived from the HEK 293 cytoplasm. These data provide evidence to support our proposed use of GALV to promote Ad penetration through tumor-associated vasculature, an approach that may substantially improve the efficiency of systemic delivery of oncolytic viruses to disseminated tumors
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