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The Natural Science Museum of Barcelona (MCNB) houses a total of 309 specimens of non–human primates. The collection comprises 102 stuffed animals, 33 skins, 73 skeletons, 24 postcranial skeletons, eight mounted skeletons, 54 skulls, three whole animals in alcohol, and 31 other samples (bones & other). Over the last two years the collection has been completely reviewed and reorganized. The collection contains 39 genera and includes a wide range of extant non–human primates. It houses specimens from Africa, Asia and South and Central America, with 10.26% of samples being Strepsirrhines, 26.92% New World monkeys and 62.18% Old World monkeys. The Museum houses some endangered or rare species. In this work we present the contents of the recent review with new and updated taxonomic attributions together with a complete list of samples that includes information on age, class and preservation status for each specimen.

A deuterium NMR study of the twist grain boundary smectic A* (TGBA*) phase in an NMR magnetic field of 9.4 T for the chiral compound 4-[4'-(1-methyl heptyloxy) biphenyl 4-(10-undecenyloxy) benzoate (11EB1M7) is reported. A comparison of the experimental and simulated spectra finds an accurate determination of the dynamic parameters in the TGBA* phase.

Deuterium decoupled proton spectra of the chain region of a partially deuteriated liquid crystal have been taken. The liquid crystal is a trimethylene chain with perdeuteriated cyanobiphenyloxy groups on either end: 1,3-bis(4,4’-cyanobiphenyloxy-d8) propane (BCBO3-d16). The spectra have been analyzed to give the dipolar couplings within the propyl chain at various temperatures in the nematic phase of the liquid crystal. These couplings are the most sensitive measurements of molecular flexibility that have yet been taken of an alkyl chain in a pure liquid crystal molecule and give a unique insight into rotational potentials of the flexible component essential to a liquid crystal molecule. The couplings have been analyzed using a maximum entropy method designed for a two-rotor system; in our case the two C–C bonds in the propyl chain. The analysis was also performed by adding to the data set the deuterium quadrupolar splittings of the chain hydrogen atoms, previously measured on the same molecule but deuteriated in the chain. The method picks out the flattest distribution consistent with the data. This also happens to be the most likely distribution given only the data used in the analysis and no other constraints.The results for BCBO3-d16 show a probability maximum for a partially eclipsed conformation (twisted approximately 86° in opposite directions about each C–C bond from the all-trans conformation), a smaller maximum for the all-trans conformation itself, and no significant probability for any of the gauche conformations. The possible motions, that are suggested by these results, therefore, are concerted librations (±86°) between the all-trans position and the partially eclipsed conformations, and full (360°) rotations. These results are in stark contrast to the assumptions made in the rotational isomeric state (RIS) model that the probability distribution can be well approximated by constraining the molecules to... [ABSTRACT FROM AUTHOR]

A new method is described of deriving a distribution, P(x), in a set of variables, x, which is consistent with a set of data, A(x), and which is the least biased modification (maximizes entropy) of a constraining distribution, r(x). The method is demonstrated using nuclear spin dipolar couplings obtained for n-alkanes dissolved in a liquid crystalline solvent. The constraining distributions are obtained from computer simulations of the molecular dynamics. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]