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The hydrophobic hydration of fullerenes in water is of significant interest as the most common Buckminsterfullerene (C60) is a mesoscale sphere; C60also has potential in pharmaceutical and nanomaterial applications. We use an all-atom molecular dynamics simulation lasting hundreds of nanoseconds to determine the behavior of a single molecule of C60in a periodic box of water, and compare this to methane. A C60molecule does not induce drying at the surface; however, unlike a hard sphere methane, a hard sphere C60solute does. This is due to a larger number of attractive Lennard-Jones interactions between the carbon atom centers in C60and the surrounding waters. In these simulations, water is not uniformly arranged but rather adopts a range of orientations in the first hydration shell despite the spherical symmetry of both solutes. There is a clear effect of solute size on the orientation of the first hydration shell waters. There is a large increase in hydrogen-bonding contacts between waters in the C60first hydration shell. There is also a disruption of hydrogen bonds between waters in the first and second hydration shells. Water molecules in the first hydration shell preferentially create triangular structures that minimize the net water dipole near the surface near both the methane and C60surface, reducing the total energy of the system. Additionally, in the first and second hydration shells, the water dipoles are ordered to a distance of 8 Å from the solute surface. We conclude that, with a diameter of approximately 1 nm, C60behaves as a large hydrophobic solute. [ABSTRACT FROM AUTHOR]

Zusammenfassung  Bei der gro�en Vielfalt der Tibiakopffrakturen unterscheidet man Plateau-, Luxations- und Tr�mmerfrakturen. Faktoren f�r die Entwicklung einer posttraumatischen Gonarthrose nach einer Tibiakopffraktur sind: nicht anatomisch ausgeheilte Gelenkfl�chen, Achsfehlstellungen, unbehandelte Begleitverletzungen. Das Therapiekonzept richtet sich nach der Frakturmorphologie, den Weichteilkonditionen, dem biologischen Alter und Gesamtzustand des Patienten. Starke Weichteilsch�den oder instabile Situationen erfordern eine Transfixation und sekund�re definitive Versorgung. Impressions-, Spalt- oder Eminentiafrakturen k�nnen minimal-invasiv arthroskopisch reponiert und stabilisiert werden. Die schonend �ber gezielte Zug�nge eingebrachten winkelstabilen Implantate machen das beidseitige Anbringen gro�er Implantate bei Komplexfrakturen �berfl�ssig und sind auch bei Mehretagenfrakturen vorteilhaft. Bei Tr�mmerfrakturen oder schlechter Compliance des Patienten ist der Hybridfixateur externe eine gute Option. [ABSTRACT FROM AUTHOR]