Electronic interactions in fullerene spheres

The electron-phonon and Coulomb interactions inC$_{60}$, and larger fullerene spheres are analyzed. The coupling between electrons and intramolecular vibrations give corrections $\sim 1 - 10$ meV to the electronic energies for C$_{60}$, and scales as $R^{-4}$ in larger molecules. The energies associated with electrostatic interactions are of order $\sim 1 - 4$ eV, in C$_{60}$ and scale as $R^{-1}$. Charged fullerenes show enhanced electron-phonon coupling, $\sim 10$ meV, which scales as $R^{-2}$. Finally, it is argued that non only C$_{60}^{-}$, but also C$_{60}^{--}$ are highly polarizable molecules. The polarizabilities scale as $R^3$ and $R^4$, respectively. The role of this large polarizability in mediating intermolecular interactions is also discussed.Comment: 12 pages. No figure

Fatigue in low-grade glioma

Contains fulltext : 80675.pdf (publisher's version ) (Closed access)The aim of this study was to determine the prevalence and severity of fatigue in long-term survivors with a low-grade glioma (LGG), and to analyze the relationship between fatigue and demographic variables, disease duration, tumor characteristics, former tumor treatment modalities, antiepileptic drug (AED) use, self-reported concentration, motivation, and activity. Fifty-four patients with stable disease (age range, 25-73 years) who were diagnosed and treated more than 8 years ago were included in this study. Fatigue was analyzed with the Checklist Individual Strength (CIS). Thirty-nine percent of the LGG patients were severely fatigued, with older patients being most affected. Severe fatigue was associated with AED use, and with reduced self-reported concentration, motivation, and activity. No relation was found between fatigue and gender, histology, tumor laterality, disease duration, type of neurosurgical intervention and radiation treatment. Fatigue is a severe problem in a large proportion of long-term surviving LGG patients