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Ahmed M Mohammed

Publications and source records attributed to Ahmed M Mohammed.

3 recordsLinked to original sources
PubMed2006

Water exchange dynamics of manganese(II), cobalt(II), and nickel(II) ions in aqueous solution.

The first row transition metal ions Mn(2+), Co(2+), and Ni(2+) have been studied by classical umbrella sampling molecular dynamics simulations. The water exchange mechanisms, estimates of reaction rates, as well as structural changes during the activation process are discussed. Mn(2+) was found to react via an I(A) mechanism, whereas Co(2+) and Ni(2+) both proceed via I(D). Reaction rate constants are generally higher than those obtained by experiment but the simply constructed metal(II) ion-water potential reproduces the relative order quite well.

Cobalt↗
PubMed2003

Nonosseous abnormalities on bone scans.

Although bone scanning is a test primarily concerned with skeletal abnormalities, important nonosseous findings are occasionally present on the images. To gauge the significance of such nonosseous uptake and, in particular, to determine whether these findings contain useful diagnostic information, the technical and medical staff in nuclear medicine must recognize the various patterns of nonbony uptake and understand their causes. The objectives of this article are to demonstrate the appearances of nonosseous uptake on bone scans, to categorize the forms of soft-tissue uptake, to emphasize technical artifacts leading to soft-tissue uptake, and to highlight the clinical significance of pathologic soft-tissue uptake.

Artifacts↗