Synthesis of YBa2Cu3O(7-δ) and Y2BaCuO5 nanocrystalline powders for YBCO superconductors using carbon nanotube templates.

We fabricate nanosized superconducting YBa(2)Cu(3)O(7-δ) (Y-123) and nonsuperconducting Y(2)BaCuO(5) (Y-211) powders using carbon nanotubes as template. The mean particle size of Y-123 and Y-211 is 12 and 30 nm, respectively. The superconducting transition temperature of the Y-123 nanopowder is 90.9 K, similar to that of commercial, micrometer-scale powders fabricated by conventional processing. The elimination of carbon and the formation of a high purity superconducting phase both on the micro- and macroscale is confirmed by Raman spectroscopy and X-ray diffraction. We also demonstrate improvement in the superconducting properties of YBCO single grain bulk samples fabricated using the nanosize Y-211 powder, both in terms of trapped field and critical current density. The former reaches 553 mT at 77 K, with a ∼20% improvement compared to samples fabricated from commercial powders. Thus, our processing method is an effective source of pinning centers in single grain superconductors.

HCA Voices Make Council Debut.

I have been an RCN member since 2002 when healthcare assistants (HCAs) had to have an NVQ level 3 to join - so I got one. Soon after, with encouragement from the general secretary and chair of congress, I was the first HCA to vote and speak at RCN congress - in a speech in favour of nursery nurses joining the RCN with an NVQ level 2 qualification.

Evidence of resilience: neuroimaging in former prisoners of war.

In this study, single voxel proton magnetic resonance spectroscopic imaging ((1)H-MRS) and volumetric analysis of hippocampal magnetic resonance imaging (MRI) images were used to determine if any differences in hippocampal biochemistry or volume were present between former prisoners of war (POWs) with and without posttraumatic stress disorder (PTSD) and control subjects matched for age and education. This study did not find lower hippocampal concentrations of N-acetylaspartate (NAA), smaller hippocampal volumes, or more impaired memory function in older veterans with PTSD compared with a group matched for traumatic experience or a nontraumatized control group.

Relationship of in vivo medial temporal lobe magnetic resonance spectroscopy to documented combat exposure in veterans with chronic posttraumatic stress disorder.

Veterans diagnosed with combat-related posttraumatic stress disorder (PTSD) and comparison subjects underwent single voxel proton magnetic resonance spectroscopy (1H-MRS) of the medial temporal lobe (MTL). PTSD subjects were divided into combat and non-combat groups based on military records. Combat PTSD subjects did not have lower MTL levels of N-acetylaspartate compared with non-combat PTSD subjects.

A practical route for the fabrication of large single-crystal (RE)-Ba-Cu-O superconductors.

Single-crystal superconductors of the general formula (LRE)-Ba-Cu-O (light rare earth, LRE = Nd, Sm, Eu and Gd) have considerable potential for engineering applications because of their ability to trap magnetic fields significantly higher than those achievable with permanent magnets. But the lack of a process by which these materials can be fabricated reliably and economically in the form of large single grains has severely hindered their development. We report a practical processing method for the fabrication in air of single-crystal (RE)BCO. The technique is economical and offers considerable freedom in terms of the processing parameters and reproducibility in growth of oriented single grains. The process is based primarily on the development of a new type of generic seed crystal that can effectively promote the epitaxial nucleation of any (RE)BCO system, and secondly on suppressing the formation of RE-Ba solid solution in a controlled manner within large grains processed in air.

In vivo proton magnetic resonance spectroscopy of the medial temporal lobes of former prisoners of war with and without posttraumatic stress disorder.

Proton magnetic resonance spectroscopy was used to compare medial temporal lobe (MTL) concentrations of N-acetylaspartate and choline between former prisoners of war (POWs) with and without posttraumatic stress disorder (PTSD). MTL N-acetylaspartate and reexperiencing symptoms correlated strongly in the POW subjects with PTSD, suggesting a relationship between reexperiencing symptoms and the integrity of MTL structures.