[Identification of fresh and old vertebral compression fractures by MRI].

Objective: To analyze and explore the value of MRI in distinguishing fresh from old vertebral compression fractures.

Methods: The features of MRI in 43 cases with compression fractures of thoracic or lumbar vertebral bodies were analyzed. MRI sequences included T1WI, T2WI and STIR.

XAFS studies and computational simulation of calixcrowns-caesium complexes in solution.

Caesium L(3)-edge XANES (X-ray absorption near-edge structure) and EXAFS (extended X-ray absorption fine structure) have been evaluated as means of probing the local structure and the interaction of caesium ions with BPC6 {1,3-alternate bis(2-propyloxy)calix[4]arenecrown-6}, BOC6 {1,3-alternate bis(octyloxy)calix[4]arenecrown-6} and BisC6 (1,3-alternate calix[4]arene bis-crown-6) in NPME (o-nitrophenyl methyl ether) or OA (n-octyl alcohol). The XANES results indicate that the molecular symmetry is enhanced as the caesium ions are embedded. The EXAFS spectra demonstrate that the coordination numbers (N) and average distances (R) from the central caesium ion to the O atoms are: for BPC6, N = 7.