Multiple Cholesterol Emboli Syndrome: Bowel Infarction After Retrograde Angiography

• The two patients described In this article are among the first to have been diagnosed with extensive bowel infarction as a result of cholesterol embolization following cardiac catheterization. The presence of acute hypertension, renal insufficiency, livedo reticularis, and gangrenous skin changes are characteristic manifestations of the multiple cholesterol emboli syndrome. Additionally, gastrointestinal symptoms and melena may herald ischemia and Infarction of the alimentary tract. Anticoagulation and thrombolytic therapy are relatively contraindicated In this syndrome and may, In fact, be a precipitating cause. The prognosis is usually poor; however, survival is possible with aggressive medical and surgical therapy, despite extensive infarction of the gastrointestinal tract and other organs. Prevention remains the most critical aspect of management of this potentially catastrophic illness.(Arch Intern Med. 1989;149:2371-2374

Ab initio calculations as a quantitative tool in the inelastic neutron scattering study of a single-molecule magnet analogue

Ab initio calculations of the electronic structure of Na9[Tb(W5O18)2] have allowed interpretation of the inelastic neutron scattering spectra, revealing the subtle relationship between molecular geometry and magnetic properties of two isostructural species.</p

Magnetic Excitations in Polyoxotungstate-Supported Lanthanoid Single-Molecule Magnets: An Inelastic Neutron Scattering and ab Initio Study

Inelastic neutron scattering (INS) has been used to investigate the crystal field (CF) magnetic excitations of the analogs of the most representative lanthanoid–polyoxometalate single-molecule magnet family: Na₉[Ln­(W₅O₁₈)₂] (Ln = Nd, Tb, Ho, Er). Ab initio complete active space self-consistent field/restricted active space state interaction calculations, extended also to the Dy analog, show good agreement with the experimentally determined low-lying CF levels, with accuracy better in most cases than that reported for approaches based only on simultaneous fitting to CF models of magnetic or spectroscopic data for isostructural Ln families. In this work we demonstrate the power of a combined spectroscopic and computational approach. Inelastic neutron scattering has provided direct access to CF levels, which together with the magnetometry data, were employed to benchmark the ab initio results. The ab initio determined wave functions corresponding to the CF levels were in turn employed to assign the INS transitions allowed by selection rules and interpret the observed relative intensities of the INS peaks. Ultimately, we have been able to establish the relationship between the wave function composition of the CF split Ln^III ground multiplets and the experimentally measured magnetic and spectroscopic properties for the various analogs of the Na₉[Ln­(W₅O₁₈)₂] family