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Attractive Way (attractive + way)
Selected AbstractsConjugated-Polymer Blends for OptoelectronicsADVANCED MATERIALS, Issue 38-39 2009Christopher R. McNeill Abstract Solution-processed polymer optoelectronic devices such as light-emitting diodes and solar cells have many advantages for large-area manufacture, and show increasing levels of performance. Here, we review recent progress in using blends of two conjugated polymers for optoelectronic devices. The blending of two or more polymers allows tuning of device performance, and for photovoltaics presents an attractive way to combine donor and acceptor materials with a morphology controlled by polymer phase separation. We discuss recent advances in imaging the microstructure of conjugated polymer blends, and we demonstrate how the blend structure leads to performance advantages in both LEDs and photovoltaic devices. [source] Direct characterization of phase behavior and compatibility in PET/HDPE polymer blends by confocal Raman mappingJOURNAL OF RAMAN SPECTROSCOPY, Issue 3 2007Shuangyan Huan Abstract Morphology, chemical distribution and domain size in poly(ethylene terephthalate)/high-density poly(ethylene) (PET/HDPE) polymer blends of various ratios prepared with and without maleic anhydride have been analyzed with confocal Raman mapping and SEM. The ratioimage method introduced here allows us to obtain enhanced chemical images with higher contrast and reliability. Compatibility numbers (Nc) are calculated to evaluate the compatibility of the blends. The incompatible polymer blends show heterogeneous distribution with phase separation behavior, while the semicompatible blends prepared with maleic anhydride show much smaller subphase distributions with less distinct interphases. After the blending modification by maleic anhydride of only 0.5%, the viscosity status and dispersibility between PET and HDPE could be substantially improved, and the interactions that exist between the two phases have also been proved by ATR-FT-IR results. High-spatial-resolution confocal Raman mapping coupled with the ratioimage method provides a very attractive way to characterize the compatibility and phase behavior of the polymer blend through different blending methodologies. Copyright © 2006 John Wiley & Sons, Ltd. [source] Silicon Nitride,Silicon Carbide Nancocomposites Fabricated by Electric-Field-Assisted SinteringJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 3 2003Julin Wan Starting with Si-C-N(-O) amorphous powders, and using the electric field assisted sintering (EFAS) technique, silicon nitride/silicon carbide nanocomposites were fabricated with yttria as an additive. It was found that the material could be sintered in a relatively short time (10 min at 1600°C) to satisfactory densities (2.96,3.09 g/cm3) using 1,8 wt% yttria. With decreasing yttria content, the ratio of SiC to Si3N4 increased, whereas the grain size decreased from ,150 nm to as small as 38 nm. This offers an attractive way to make nano-nanocomposites of silicon nitride and silicon carbide. [source] Review article: the treatment of non-alcoholic steatohepatitis with thiazolidinedionesALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2005H. REYNAERT Summary It is generally accepted that non-alcoholic fatty liver disease will be the most frequent liver disease in the near future and that the management of patients with non-alcoholic fatty liver disease will be a challenge for hepatologists in the next decades. Non-alcoholic fatty liver disease is considered the hepatic manifestation of the metabolic syndrome, in which insulin resistance plays a crucial role. Although steatosis will often not progress to severe liver disease, in some patients, it results in cirrhosis and even hepatocellular carcinoma. Therefore, it is important to identify those patients at risk for developing fibrosis. Age, diabetes, obesity and hypertriglyceridaemia are independent risk factors for fibrosis in patients with elevated serum alanine aminotransferase levels and steatosis on ultrasound. The presence of multiple metabolic disorders increases the risk. Apart from diet, exercise and correction of underlying metabolic abnormalities, no specific treatment is available at the moment. Theoretically, thiazolidinediones are an attractive way to treat non-alcoholic fatty liver disease, because they improve insulin resistance. Some preliminary studies with thiazolidinediones were encouraging, as steatosis, inflammation and fibrosis improved in a substantial number of patients. Although no serious side effects occurred in the pilot studies, we should look vigilantly for hepatotoxicity, as the first generation thiazolidinediones proved to be toxic for the liver. [source] Recombinant protein expression and solubility screening in Escherichia coli: a comparative studyACTA CRYSTALLOGRAPHICA SECTION D, Issue 10 2006Nick S. Berrow Producing soluble proteins in Escherichia coli is still a major bottleneck for structural proteomics. Therefore, screening for soluble expression on a small scale is an attractive way of identifying constructs that are likely to be amenable to structural analysis. A variety of expression-screening methods have been developed within the Structural Proteomics In Europe (SPINE) consortium and to assist the further refinement of such approaches, eight laboratories participating in the network have benchmarked their protocols. For this study, the solubility profiles of a common set of 96 His6 -tagged proteins were assessed by expression screening in E. coli. The level of soluble expression for each target was scored according to estimated protein yield. By reference to a subset of the proteins, it is demonstrated that the small-scale result can provide a useful indicator of the amount of soluble protein likely to be produced on a large scale (i.e. sufficient for structural studies). In general, there was agreement between the different groups as to which targets were not soluble and which were the most soluble. However, for a large number of the targets there were wide discrepancies in the results reported from the different screening methods, which is correlated with variations in the procedures and the range of parameters explored. Given finite resources, it appears that the question of how to most effectively explore `expression space' is similar to several other multi-parameter problems faced by crystallographers, such as crystallization. [source] IN DEFENCE OF PRIORITY REVIEW VOUCHERSBIOETHICS, Issue 7 2009JORN SONDERHOLM ABSTRACT Infectious and parasitic diseases cause enormous health problems in the developing world whereas they leave the developed one relatively unscathed. Research and development (R&D) of drugs for diseases that mainly affect people in developing countries is limited. The problem that relatively few drugs are available for diseases that cause an enormous burden of disease in the developing world is called the ,availability problem'. In recent years, the availability problem has received quite a bit of attention. A number of proposals have been fielded as to how this problem might be minimized. Wild-card patent extensions, advance market commitments, cash prizes and the Health Impact Fund are prominent examples of such proposals. These proposals can be thought of as pull-mechanisms for R&D of drugs for neglected diseases. What has been coined a ,priority review voucher' is another pull-mechanism. This paper is a critical discussion of this pull-mechanism. First, the original priority review voucher scheme, as proposed by Ridley et al. (2006), is described. A number of objections to this scheme are thereafter presented. A few amendments to the original scheme are then suggested, and it is argued that with these amendments in place, the priority review voucher scheme constitutes an attractive way of stimulating R&D of drugs for neglected diseases. [source] Using fractional exhaled nitric oxide to guide asthma therapy: design and methodological issues for ASthma TReatment ALgorithm studiesCLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2009P. G. Gibson Prof. Summary Background Current asthma guidelines recommend treatment based on the assessment of asthma control using symptoms and lung function. Noninvasive markers are an attractive way to modify therapy since they offer improvedselection of active treatment(s) based on individual response, and improvedtitration of treatment using markers that are better related to treatment outcomes. Aims: To review the methodological and design features of noninvasive marker studies in asthma. Methods Systematic assessment of published randomized trials of asthma therapy guided by fraction of exhaled nitric oxide(FENO). Results FENO has appeal as a marker to adjust asthma therapy since it is readily measured, gives reproducible results, and is responsive to changes in inhaled corticosteroid doses. However, the five randomised trials of FENO guided therapy have had mixed results. This may be because there are specific design and methodological issues that need to be addressed in the conduct of ASthma TReatment ALgorithm(ASTRAL) studies. There needs to be a clear dose response relationship for the active drugs used and the outcomes measured. The algorithm decision points should be based on outcomes in the population of interest rather than the range of values in healthy people, and the algorithm used needs to provide a sufficiently different result to clinical decision making in order for there to be any discernible benefit. A new metric is required to assess the algorithm performance, and the discordance:concordance(DC) ratio can assist with this. Conclusion Incorporating these design features into future FENO studies should improve the study performance and aid in obtaining a better estimate of the value of FENO guided asthma therapy. [source] | ||||||||||||||||