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Metal-supported solid oxide fuel cells (SOFCs) composed of a Ce0.8Sm0.2O2−δ (SDC) electrolyte layer and Ni-Ce0.8Sm0.2O2−δ (Ni-SDC) cermet anode were fabricated by suspension thermal spraying on Hastelloy × substrates. The cathode, a Sm0.5Sr0.5CoO3 (SSCo)-SDC composite, was screen-printed and fired in situ. The anode was produced by suspension plasma spraying (SPS) using an axial injection plasma torch. The SDC electrolyte was produced by high-velocity oxy-fuel (HVOF) spraying of liquid suspension feedstock, using propylene fuel (DJ-2700). The emerging technology of HVOF suspension spraying was explored here to produce thin and low-porosity electrolytes in an effort to develop a cost-effective and scalable fabrication technique for high-performance, metal-supported SOFCs. In-flight particle temperature and velocity were measured for a number of different gun operating conditions and standoff distances and related to the resulting microstructures. At optimized conditions, this approach was found to limit material decomposition, enhance deposition efficiency, and reduce defect density in the resulting coating, as compared to previous results reported with SPS. Produced button cells showed highly promising performance with a maximum power density (MPD) of 0.5 W cm−2 at 600 °C and above 0.9 W cm−2 at 700 °C, with humidified hydrogen as fuel and air as oxidant. The potential of this deposition technique to scale-up the substrate size to 50 × 50 mm was demonstrated. [ABSTRACT FROM AUTHOR]

Cancer incidence in 1990-92 among English south Asian (residents with ethnic origins in India, Pakistan or Bangladesh) and non-south Asian children is compared. Standardized incidence ratios show significant overall excesses in south Asians (131), largely due to higher rates in south Asian boys, and specific excesses for leukaemia (141), lymphoid leukaemia (141), lymphoma (172) and hepatic tumours (375). Aetiological investigation is required. [ABSTRACT FROM AUTHOR]

A variety of spray pyrolysis (SP) techniques have been developed to directly produce ceramic powders from solutions. Examples that are discussed include the following powders: (La0.8Sr0.2)0.9MnO3-YSZ (La(Sr)MnO3-YSZ), La0.6Sr0.4CoO3 (La(Sr)CoO3), (CeO2)0.8(SmO1.5)0.2-NiO (SDC-NiO) and La0.9Sr0.1Ga0.8Mg0.2O3-NiO (LSGM-NiO). For all these powders, spherical, non-agglomerated, submicrometer particles were obtained from aqueous solution of metal salts into a furnace using an ultrasonic atomizer at 1.7 MHz. After SP some of the particles exhibit a hollow-shell morphology. Subsequent calcination at 1000°C yielded crystalline particles. The electrical performance of Ni-SDC/LSGM/La(Sr)CoO3 fuel cells operating at 800°C, prepared from the powders obtained by SP, is reported. [ABSTRACT FROM AUTHOR]

Cancer incidence among English south Asians (residents in England with ethnic origins in India, Pakistan or Bangladesh) is described and compared with non-south Asian and Indian subcontinent rates. The setting for the study was areas covered by Thames, Trent, West Midlands and Yorkshire cancer registries. The study identified 356 555 cases of incident cancer (ICD9:140-208) registered between 1990 and 1992, including 3845 classified as English south Asian. The main outcome measures were age specific and directly standardized incidence rates for all cancer sites (ICD9:140-208). English south Asian incidence rates for all sites combined were significantly lower than non-south Asian rates but higher than Indian subcontinent rates. English south Asian rates were substantially higher than Indian subcontinent rates for a number of common sites including lung cancer in males, breast cancer in females and lymphoma in both sexes. English south Asian rates for childhood and early adult cancer (0-29 years) were similar or higher than non-south Asian rates. English south Asian rates were significantly higher than non-south Asian rates for Hodgkin's disease in males, cancer of the tongue, mouth, oesophagus, thyroid gland and myeloid leukaemia in females, and cancer of the hypopharynx, liver and gall bladder in both sexes. The results are consistent with a transition from the lower cancer risk of the country of ethnic origin to that of the country of residence. They suggest that detrimental changes in lifestyle and other exposures have occurred in the migrant south Asian population. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFC) play a key role for sustainable energy; however, catalyst degradation remains one of the main challenges for competing with traditional energy technologies. The Pt/C commercially available electrocatalysts are susceptible to Pt dissolution and carbon support corrosion. In this context, we design a Pt–NbOx catalyst supported on TiN nanoparticles as an alternative electrocatalyst for the oxygen reduction reaction (ORR). The use of Pt–NbOx reduces materials' costs by lowering the required platinum loading and improving catalyst performance. The TiN support is selected to improve support stability. The electrocatalyst is successfully synthesized by a one-step flame spray process called reactive spray deposition technology. Electrocatalyst with two different very low Pt loadings (0.032 mg cm−2 and 0.077 mg cm−2) are investigated and their performance as cathode is evaluated by the rotating disk electrode method. The new electrocatalyst based on Pt–NbOx supported on TiN has ORR performance that is comparable to the state-of-the-art Pt/C electrocatalyst. A half-wave potential of 910 mV was observed in the polarization curves, as well as a mass activity of 0.120 A∙mgPt−1 and a specific activity of 283 μA∙cmPt−2 at 0.9 V. These results demonstrate that Pt–NbOx on TiN electrocatalyst has the potential for replacing Pt/C cathode in PEMFC. [ABSTRACT FROM AUTHOR]

Details the link between obesity and esophageal adenocarcinoma. Increase of intra-abdominal pressures; Effect of weight loss on symptoms of gastro-esophageal reflux; Implications in the management of Barrett's esophagus.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012. [ABSTRACT FROM PUBLISHER]

A letter to the editor is presented in response to the article "Influenza and COPD mortality protection as pleiotropic, dose-dependent effects of statins," by Floyd J. Frost, Hans Petersen and Kristine Tollestrup in the April 2007 issue.