Non magnetic supermirrors produced at Mirrotron Ltd

Non magnetic neutron guides are needed where polarized neutrons are to be transmitted. Mirrotron Ltd. is able to produce guides of standard length and width coated with non magnetic Ni Mo Ti supermirrors. Hot pressed and vacuum melted Ni Mo targets were tried out for the sputtering process. High quality Ni Mo Ti supermirrors with various critical angles were produced. The reflectivity at the critical angle was 0.97, 0.95, 0.92, 0.9 and 0.85 for m 1.2, 1.5, 2, 2.5 and 3, respectively. The non magnetic properties of the mirrors were proved at HMI using polarized neutron

Neutron supermirror development

Supermirrors are aperiodic multilayers of two materials, which allow reflecting neutrons at small grazing angles. They are used mainly for the transport of neutrons through guides or for polarization. The first part of the article describes the improvements of Ni Ti supermirrors for guides in the Budapest laboratories, which were achieved by relating the crystalline structure of supermirrors to their reflectivity. Furthermore the behavior of supermirrors under heat load and irradiation was characterized and the homogeneity of the coating process improved. This made it possible to produce Ni Ti supermirrors with m 4. In the second part from the Berlin laboratory the polarization of neutrons is introduced and several methods to prepare polarized neutron beams are described with the emphasis on polarizing supermirrors. They reflect only one spin component and transmit the other one. The main challenge today is to increase the number of layers, which requires improved interfaces between the layers and reduced stress in the layers. In the last years the number of layers was increased from 150 to 1000 and the m value from m 2.3 to m 3.4

Serious Asthma Events with Fluticasone plus Salmeterol versus Fluticasone Alone

BACKGROUND: The safe and appropriate use of long-acting beta-agonists (LABAs) for the treatment of asthma has been widely debated. In two large clinical trials, investigators found a potential risk of serious asthma-related events associated with LABAs. This study was designed to evaluate the risk of administering the LABA salmeterol in combination with an inhaled glucocorticoid, fluticasone propionate. METHODS: In this multicenter, randomized, double-blind trial, adolescent and adult patients (age, ≥12 years) with persistent asthma were assigned to receive either fluticasone with salmeterol or fluticasone alone for 26 weeks. All the patients had a history of a severe asthma exacerbation in the year before randomization but not during the previous month. Patients were excluded from the trial if they had a history of life-threatening or unstable asthma. The primary safety end point was the first serious asthma-related event (death, endotracheal intubation, or hospitalization). Noninferiority of fluticasone-salmeterol to fluticasone alone was defined as an upper boundary of the 95% confidence interval for the risk of the primary safety end point of less than 2.0. The efficacy end point was the first severe asthma exacerbation. RESULTS: Of 11,679 patients who were enrolled, 67 had 74 serious asthma-related events, with 36 events in 34 patients in the fluticasone-salmeterol group and 38 events in 33 patients in the fluticasone-only group. The hazard ratio for a serious asthma-related event in the fluticasone-salmeterol group was 1.03 (95% confidence interval [CI], 0.64 to 1.66), and noninferiority was achieved (P=0.003). There were no asthma-related deaths; 2 patients in the fluticasone-only group underwent asthma-related intubation. The risk of a severe asthma exacerbation was 21% lower in the fluticasone-salmeterol group than in the fluticasone-only group (hazard ratio, 0.79; 95% CI, 0.70 to 0.89), with at least one severe asthma exacerbation occurring in 480 of 5834 patients (8%) in the fluticasone-salmeterol group, as compared with 597 of 5845 patients (10%) in the fluticasone-only group (P<0.001). CONCLUSIONS: Patients who received salmeterol in a fixed-dose combination with fluticasone did not have a significantly higher risk of serious asthma-related events than did those who received fluticasone alone. Patients receiving fluticasone-salmeterol had fewer severe asthma exacerbations than did those in the fluticasone-only group