Movilización aséptica, simultánea y bilateral por rotura de la copa acetabular en una paciente de 43 años / Aseptic, simultaneous and bilateral mobilisation due to an acetabular shell fracture in a 43 year-old patient

La movilización del componente acetabular en una prótesis total de cadera (PTC) es la principal complicación en este tipo de cirugía. Además, los casos de rotura del cótilo llevan casi siempre a su movilización. Presentamos el caso de una mujer de 43 años con movilización aséptica por separación de la malla reticular bilateral del cotilo después de 13 y 14 años de la intervención (AU)

The acetabular shell mobilization is the main long-term complication in total hip replacement. Metal-back fracture has also to be considered among the possible causes of shell mobilization. A case is presented of bilateral acetabular shell mobilization due to the trabecular covering de-soldering from the metal-back in a 43 year-old patient, 13-14 years after the first surgery (AU)

[Aseptic, simultaneous and bilateral mobilisation due to an acetabular shell fracture in a 43 year-old patient]. / Movilización aséptica, simultánea y bilateral por rotura de la copa acetabular en una paciente de 43 años.

The acetabular shell mobilization is the main long-term complication in total hip replacement. Metal-back fracture has also to be considered among the possible causes of shell mobilization. A case is presented of bilateral acetabular shell mobilization due to the trabecular covering de-soldering from the metal-back in a 43 year-old patient, 13-14 years after the first surgery.

A comparative study of the responses of lithium borate and calcium sulphate phosphors in a TL personal dosemeter.

This work summarises the results of a series of experiences made on Panasonic UD-802AS, a multi-element dosemeter that is currently used in Caorso Nuclear Power Plant for personnel external monitoring. Two main topics have been considered: energy response and the influence of working place dose rate on relative readings of the elements at the end of the monitoring period. The presence of four elements of different materials and filtrations gives the possibility of evaluating radiation energy by a simple algorithm, so that an accurate estimate of the personal dose equivalent can be provided; the good results of the participation of Caorso Individual Monitoring Service (IMS) to 'EURADOS 2008 intercomparison on whole-body dosemeters' account for the reliability of the method. A study on the response in low-dose rate fields is also reported, giving in practice interesting information about operational conditions.

Infinite-layer iron oxide with a square-planar coordination.

Conventional high-temperature reactions limit the control of coordination polyhedra in transition-metal oxides to those obtainable within the bounds of known coordination geometries for a given transition metal. For example, iron atoms are almost exclusively coordinated by three-dimensional polyhedra such as tetrahedra and octahedra. However, recent works have shown that binary metal hydrides act as reducing agents at low temperatures, allowing access to unprecedented structures. Here we show the reaction of a perovskite SrFeO3 with CaH2 to yield SrFeO2, a new compound bearing a square-planar oxygen coordination around Fe2+. SrFeO2 is isostructural with 'infinite layer' cupric oxides, and exhibits a magnetic order far above room temperature in spite of the two-dimensional structure, indicating strong in-layer magnetic interactions due to strong Fe d to O p hybridization. Surprisingly, SrFeO2 remains free from the structural instability that might well be expected at low temperatures owing to twofold orbital degeneracy in the Fe2+ ground state with D(4h) point symmetry. The reduction and the oxidation between SrFeO2 and SrFeO3 proceed via the brownmillerite-type intermediate SrFeO2.5, and start at the relatively low temperature of approximately 400 K, making the material appealing for a variety of applications, including oxygen ion conduction, oxygen gas absorption and catalysis.

Structural organization of guanosine derivatives in dilute solutions: small angle neutron scattering analysis.

Guanosine derivatives, dissolved in water, can form cholesteric and hexagonal mesophases. The common structural unit is a chiral rod-shaped aggregate consisting of a stack of Hoogsten-bonded guanosine tetrameric disks. In order to elucidate the self-association process, we decided to investigate, by small-angle neutron scattering, the structural properties of d(pG), d(GpG), d(GpGpG), d(GpGpGpG) and d(GpGpGpG pGpG) derivatives in very dilute solutions. Under our experimental conditions only d(pG) seems not to form detectable particles. On the other hand, the results for the other derivatives indicate that cylindrical aggregates, having a 10 A cross-section gyration radius and a length of about 70 A, exist in the isotropic phase. According to the structure of the hexagonal and cholesteric phases, we fitted the experimental data by using a model of rod-shaped aggregates formed by stacking about 18 to 20 guanosine tetramers. Moreover, from the measurement of the concentration of scattering particles, we deduced that guanosine derivatives are only partially aggregated, depending on their ability to form mesophases.