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The UK Government has said that energy companies can invest in new nuclear power stations. As part of this, the safety, security and environmental regulators (the Nuclear Directorate of the Health and Safety Executive and the Environment Agency in England and Wales) are engaged in a process known as generic design assessment (GDA) that was proposed by UK Government to improve the process of consulting on and approving new nuclear power stations. The GDA process is expected to take about 3½ years to complete. From an environmental perspective, the Environment Agency is interested in assessing whether the proposed reactor designs represent the 'best available techniques' (BAT) with regard to environmental discharges. This paper describes a project that has been assessing BAT for radioactive discharges for analogues (i.e. the previous generation) of four reactor designs on which assessment work started in 2007. Where possible data on environmental discharges has been collated for individual radionuclides for a number of reactor analogues and the discharge performance has been normalized with respect to thermal and electrical outputs to allow trends in the data to be determined. Where possible, explanations for any trends have been identified.

We describe the three-dimensional holographic optical disc system for application as read-only memory. Several systems design issues are discussed including imaging optics, storage density, readout rate, and the alignment servo system. We demonstrate 40 bits/m2surface density and pixel-matched holographic data readout from a 12 cm disc spinning at 600 RPM.

We have recorded (at room temperature) as many as 500 high-resolution, uniformly diffracting volume holograms in a single Fe-doped LiNbO_3 crystal. The holograms were stored by angularly multiplexing a plane-wave reference beam. The graphical procedure that we used to compute exposure schedules is described. Experimental results are also presented.

Introduction We have recently confirmed that the presence of Schmorl's nodes (SN) was highly associated with disk degeneration in a large population-based cohort study in Southern Chinese. Based on our previous proposed classification system of SN, we attempt to further address the association of SN characteristics and the severity of disk degeneration.Materials and Methods Two independent observers assessed sagittal T2-weighted MRIs of the lumbar spine (n= 2449) for the presence and characteristics of SN, and additional radiologic features. The patterns of SN characteristics were assessed by hierarchical clustering methods. Generalized linear models were used to assess the associations of the shape and size of SN with disk degeneration severity.Results Total 401 subjects with SN (16.4%) were included in the analysis. Hierarchical clustering showed that typical SN were usually smaller in size with shape type I to III (i.e., indented endplate, sharp or rounded shape) whereas atypical SN were larger with shape type IV to V (i.e., rectangular or irregular shape). Total 8.3% of all identified SN (n= 960) were atypical SN. Multivariate ordinal logistic regression adjusted for gender, age, body mass index, smoking status, presence of disk bulge/extrusion, and high intensity zone showed that atypical SN and typical SN, depending on the lumbar levels, were associated with 5- to 13-fold and 2- to 4-fold higher risk of increased severity of disk degeneration, respectively (p< 0.05).Conclusion This was the first study to address the relationships of SN morphology to the severity of disk degeneration. The associations of SN morphology with disk degeneration severity might be clinically relevant. I confirm having declared any potential conflict of interest for all authors listed on this abstract Yes Disclosure of Interest None declared