A new weakened scheme for negative introspection in autoepistemic reasoning is proposed. The scheme is formulated proof-theoretically in terms of enumer-ations of formulae. The resulting sets of conclusions based on this negative introspec-tion principle, cautious autoepistemic expansions, generalize Moore style stable expansions such that every set of premises has a cautious expansion. A nitar...

background: radiofrequency catheter ablation (rfca) has been introduced as the treatment of choice for supraventricular tachycardia. the aim of this study was to evaluate the success rate as well as procedural and in-hospital complications of rfca for the treatment of atrioventricular nodal reentrant tachycardia (avnrt).   methods: between march 1995 and february 2009, 544 patients (75.9 % fema...

A model of left-right axis formation in the chick involves inhibition of bone morphogenetic proteins by the antagonist Car as a mechanism of upregulating Nodal in the left lateral plate mesoderm. By contrast, expression of CFC, a competence factor, which is absolutely required for Nodal signaling in the lateral plate mesoderm is dependent on a functional BMP signaling pathway. We have therefore...

UNLABELLED Metastatic melanoma is a highly aggressive skin cancer with a poor prognosis. Despite a complete response in fewer than 5% of patients, the chemotherapeutic agent dacarbazine (DTIC) remains the reference drug after almost 40 years. More recently, FDA-approved drugs have shown promise but patient outcome remains modest, predominantly due to drug resistance. As such, combinatorial targ...

In all vertebrates, invariant left/right (L/R) positioning and organization of the internal viscera is controlled by a conserved pathway. Nodal, a member of the TGFbeta superfamily is a critical upstream component responsible for initiating L/R axis determination. Asymmetric Nodal expression in the node preceeds and foreshadows morphological L/R asymmetry. Here we address the mechanism of Nodal...

In the sea urchin embryo, Nodal is the earliest known signal to play a role in the specification of the oral ectodermal territory. Nodal, a TGF-beta ligand, is first expressed in the presumptive oral ectoderm at approximately 7 H of development. Nodal overexpression produces a distinctive bell-shaped phenotype with expanded oral ectoderm, which resembles the oralized phenotype obtained as a res...

Transcription factors belonging to the FoxH1 and Mixer families are required for facets of Nodal signaling during vertebrate mesendoderm induction. Here, we analyze whether zebrafish proteins related to FoxH1 [Schmalspur (Sur)] and Mixer [Bonnie and clyde (Bon)] act within or downstream of the Nodal signaling pathway, test whether these two factors have additive or overlapping activities, and d...

OBJECTIVE To study the architecture of the human sinus node to facilitate understanding of mapping and ablative procedures in its vicinity. METHODS The sinoatrial region was examined in 47 randomly selected adult human hearts by histological analysis and scanning electron microscopy. RESULTS The sinus node, crescent-like in shape, and 13.5 (2.5) mm long, was not insulated by a sheath of fib...

Expansions of trinucleotide repeats (TNRs) are the genetic cause for a number of neurodegenerative disorders. In some of these diseases, ongoing somatic expansions in the brain are thought to contribute to disease progression. Expansions can occur in both neurons and supporting glial cells, but little is known about molecular mechanisms of expansion in these cells, particularly glia. To help ad...

The nonlinear effects of the second harmonic generation have been investigated for the propagation of light along the axis of fibers of wagon wheel cross sectional shape. Nodal finite element formulation is utilized to obtain discretized Helmholtz equations under appropriate boundary conditions. The hierarchical p-version nodal elements are used for meshing the cross section of wagon wheel fibe...