Peculiarities of nonadditive changes in conductivity of nano-PDLC under influence of magnetite and single-wall carbon nanotubes

Studied in this work has been the effect of nanoparticles – magnetite and single-wall carbon nanotubes – separately and together on the conductivity of nematic liquid crystal 6CHBTdispersed in polyvinyl alcohol. Morphology of these films was analyzed using an electron microscope. When using selected technology of homogenizing the mixture components, there takes place formation of liquid crystals dispersed in the polymer matrix with the average sizes of liquid-crystal droplets close to 500 nm (nano-PDLC). It has been found that simultaneous introduction of magnetite and nanotubes results in lowering the conductivity of nano-PDLC as compared to the total conductivity of nano-PDLC with each kind of nanoparticles separately. It has been suggested that the main mechanism of this effect lies in formation of deep centers for electron capture by complexes with different types of nanoparticles, which leads to a decrease in electronic conductivity through the polymer matrix

Predictors of survival in sporadic Creutzfeldt-Jakob disease and other human transmissible spongiform encephalopathies

A collaborative study of human transmissible spongiform encephalopathies has been carried out from 1993 to 2000 and includes data from 10 national registries, the majority in Western Europe. In this study, we present analyses of predictors of survival in sporadic (n = 2304), iatrogenic (n = 106) and variant Creutzfeldt-Jakob disease (n = 86) and in cases associated with mutations of the prion protein gene (n = 278), including Gerstmann-Sträussler-Scheinker syndrome (n = 24) and fatal familial insomnia (n = 41). Overall survival for each disease type was assessed by the Kaplan-Meier method and the multivariate analyses by the Cox proportional hazards model. In sporadic disease, longer survival was correlated with younger age at onset of illness, female gender, codon 129 heterozygosity, presence of CSF 14-3-3 protein and type 2a prion protein type. The ability to predict survival based on patient covariates is important for diagnosis and counselling, and the characterization of the survival distributions, in the absence of therapy, will be an important starting point for the assessment of potential therapeutic agents in the futur

The Priority position paper: protecting Europe's food chain from prions

International audienceBovine spongiform encephalopathy (BSE) created a global European crisis in the 1980s and 90s, with very serious health and economic implications. Classical BSE now appears to be under control, to a great extent as a result of a global research effort that identified the sources of prions in meat and bone meal (MBM) and developed new animal-testing tools that guided policy. Priority ( www.prionpriority.eu ) was a European Union (EU) Framework Program 7 (FP7)-funded project through which 21 European research institutions and small and medium enterprises (SMEs) joined efforts between 2009 and 2014, to conduct coordinated basic and applied research on prions and prion diseases. At the end of the project, the Priority consortium drafted a position paper ( www.prionpriority.eu/Priority position paper) with its main conclusions. In the present opinion paper, we summarize these conclusions. With respect to the issue of re-introducing ruminant protein into the feed-chain, our opinion is that sustaining an absolute ban on feeding ruminant protein to ruminants is essential. In particular, the spread and impact of non-classical forms of scrapie and BSE in ruminants is not fully understood and the risks cannot be estimated. Atypical prion agents will probably continue to represent the dominant form of prion diseases in the near future in Europe. Atypical L-type BSE has clear zoonotic potential, as demonstrated in experimental models. Similarly, there are now data indicating that the atypical scrapie agent can cross various species barriers. More epidemiological data from large cohorts are necessary to reach any conclusion on the impact of its transmissibility on public health. Re-evaluations of safety precautions may become necessary depending on the outcome of these studies. Intensified searching for molecular determinants of the species barrier is recommended, since this barrier is key for important policy areas and risk assessment. Understanding the structural basis for strains and the basis for adaptation of a strain to a new host will require continued fundamental research, also needed to understand mechanisms of prion transmission, replication and how they cause nervous system dysfunction and death. Early detection of prion infection, ideally at a preclinical stage, also remains crucial for development of effective treatment strategies

The implications of global natural gas market developments for China

The ongoing transformation of the world’s gas markets is significantly altering the positions of the major global players, with the USA and China emerging as the main winners. It is clear to see that the USA, as the pioneer of the shale revolution, will receive the greatest benefits. North America will achieve complete gas self-sufficiency while low prices for hydrocarbons will boost new industrialization; it will also be able to contribute 60–80 million tonnes to the global LNG market, respond flexibly to changing market conditions, and quickly redirect supplies to the most profitable regional markets. The outcome for China is less obvious and actually quite surprising. How can an import-dependent country with booming gas demand, limited production options, and subsidized domestic prices actually become a winner in this gas ‘Great Game’? In fact China is successfully carrying out a policy of import diversification, rapid construction of the necessary infrastructure, and enhancing its position in other regions by engaging its national companies in the development of their gas resources. It also has its own large reserves of unconventional gas, which could add to the diversification of its supply mix. China’s balanced and forward-looking policy will allow the country to share the fruits of the shale revolution with the USA and benefit from the unique situation that is currently evolving in global gas markets.</p