In type-II string theory compactifications on Calabi-Yau manifolds, topological string theory partition functions give a class of exact F-terms in the 4d effective action. We point out that in the background of constant self-dual field strength, these terms deform the central charges for D-branes wrapping Calabi-Yau manifold to include string loop corrections. We study the corresponding loop co...

To the Editor: In a recent issue of Circulation, we saw the interesting images concerning magnetic resonance angiography in a patient with criss-cross heart.1 In the description of the case, the authors correctly report the atrial situs (solitus), the position of the ventricle (inverted), and the connection of the great arteries (discordant with L-position of the aorta). This is the most freque...

Intraspecific sequence variation in the D-loop region of mtDNA in white sturgeon (Acipenser transmontanus), a relict North American fish species, was examined in 27 individuals from populations of the Columbia and Fraser rivers. Thirty-three varied nucleotide positions were present in a 462-nucleotide D-loop sequence, amplified using the polymerase chain reaction. Bootstrapped neighbor-joining ...

The displacement loop (D loop) is the product of homology search and DNA strand invasion, constituting a central intermediate in homologous recombination (HR). In eukaryotes, the Rad51 DNA strand exchange protein is assisted in D loop formation by the Rad54 motor protein. Curiously, Rad54 also disrupts D loops. How these opposing activities are coordinated toward productive recombination is unk...

BACKGROUND The purpose of this study was to characterize somatic mutations in the D-loop of mitochondrial DNA (mtDNA) and their impact on survival in patients with head and neck cancer. METHODS Histologically confirmed head and neck cancer and corresponding noncancerous tissues were obtained from 130 patients. The D-loop of mtDNA sequence in noncancerous tissues was compared with that of pair...

DNA methylation occurs in the displacement loop (D-loop) region of mammals; however, D-loop regions of certain tumor tissue types were found to be de‑methylated. Whether hypomethylation of the D‑loop region is involved in the regulation of the mitochondrial DNA (mtDNA) copy number and nicotinamide adenine dinucleotide subunit 2 (ND‑2) expressions in colorectal cancer has remained elusive. In th...