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The Cenozoic tectonic history of NW Europe is generally attributed to some combination of three principal controlling factors: North Atlantic opening, Alpine collision and formation of the Icelandic mantle plume. Using constraints from the high-resolution Tellus aeromagnetic survey of Northern Ireland, we show that Palaeogene tectonics can be attributed to approximately north-south Alpine-related compression, forming NNW-SSE-trending dextral and ENE-WSW-trending sinistral conjugate strike-slip faults, with the latter defined by kilometre-scale displacements along reactivated Caledonian or Carboniferous faults. This tectonism was, however, punctuated by pulsed magmatic intrusive and extrusive events, including four distinct dyke swarms that are attributed to NE-SW- to east-west-directed plume-related extension. Although this evidence shows, for the first time, that north-south Alpine compression was periodically overwhelmed by the dynamic stresses and uplift associated with pulsed mantle plume-related deformation, associated strike-slip faulting may have controlled the locus of volcanic activity and central igneous complexes, and the location of sedimentary depocentres. [ABSTRACT FROM AUTHOR]

Boundary layer transition is significant to many flow fields that include both laminar and turbulent regions. Accurate prediction of transition onset is fundamental to the modelling of these flows. In most flow solvers based on the Reynolds‐averaged Navier–Stokes equations, transition onset must be specified manually. To overcome this weakness and to more accurately predict aerodynamic flow fields, a boundary layer transition prediction methodology is presented. This methodology, which has been applied to a Navier–Stokes solver, dynamically locates transition onset as the flow solution is converging. The prediction methodology identifies several boundary layer transition mechanisms, including Tollmien–Schlichting instability, laminar separation and turbulence contamination. Where possible, the implementation utilizes the calculated boundary layer velocity profiles to strongly couple the predicted transition locations and the flow solution. The transition prediction methodology was used to predicted transition onset for the NLF(1)‐0416 and S809 single‐element wind turbine airfoils. Results obtained with numerical calculations are found to agree well with experimental observations. Copyright © 2001 John Wiley & Sons, Ltd.

The AIDS epidemic has focused attention on the constraints and deficiencies present in many blood transfusion services in the developing world. We discuss a variety of options for reducing transfusion-related HIV transmission, and suggest how new transfusion strategies may be implemented. We show that a transfusion service cannot rely solely on the screening of donor blood for anti-HIV antibodies and that a more comprehensive approach is needed. Important components of this approach include donor selection and improved clinical practice, in which blood and blood products are prescribed only when really necessary.

With the increasing scale of integration, resulting in a higher on-chip complexity, waveguide crossings with good performance are becoming increasingly important. Worst-case paths contain a high number of crossings, depending on the number of channels being processed, in switching matrices [11, multiwavelength add drop filters [2] (up to 151, and optical cross-connects [3]. Crossings with very low crosstalk and loss can be realized in fiber-matched waveguide structures as used in lithium niobate or silica-based technology [4,5]. In highly integrated semiconductor devices, crossings may contribute significantly to the loss and crosstalk performance. In this paper we present the results of a series of experiments for the design of high-performance semiconductor waveguide crossings.

Schizophrenia rates were obtained from a British Columbia coastal Indian group numbering 14 000. One subgroup numbering 12 200 showed an incidence of 10 cases per 100 000 population a year. An atypical subgroup of 1800 showed an incidence of 49 cases per 100 000 a year. These rates appear to be relevant to a hypothesis that suggests that schizophrenia may be caused by abnormal fatty acid metabolism. A study is reviewed which implies the existence of a delta-5 or delta-6 desaturase enzyme mutation or both, in the Indian population under study.

Interference of 1.48-μm light in multimode interference waveguides is made visible by imaging green and infrared upconversion luminescence from Er^3+ ions dispersed in the waveguide. A two-dimensional mode density image can be derived from the data and agrees well with mode calculations for this structure. This new technique provides an interesting tool for the study of optical mode distributions in complicated waveguide structures and photonic band-gap materials.

Space switching of 2.5 Gbit/s optical signals by wavelength conversion in a DBR laser and subsequent routing through a phased array wavelength demultiplexer is demonstrated. In addition, first results are presented using an integrated chip consisting of a phased array with 3 dB couplers at its inputs.

First experimental results of compact 1×16 splitters based on single 1×2 multimode interference (MMI) power splitters in alumina waveguides on silicon are reported.

Caudal (tail) fins of fish and aquatic mammals that cruise long distances, and wings of certain birds, often have the shape of a crescent moon. This study investigates how the crescent shape contributes to the travelling performance of these animals. A steady-flow theory1that correctly models the trailing wake was used to analyse lifting surface efficiency, which is dependent on the level of induced (or vortex) drag for a given lift and span of the lifting surface. This analysis shows that backward curvature of a wing improves induced efficiency to a value greater than that of the flat untwisted wing of elliptical shape considered optimal in classical wing theory2,3. This increase of induced efficiency results from the nonplanar trailing vortex sheet produced by the crescent-shaped wing at a given angle of attack.

This study investigates the performance of microjets for load reduction on the NREL-5 MW wind turbine and identifies optimal system parameters. Microjets provide blowing normal to the blade surface and can rapidly increase or decrease lift on a blade section, enabling a wind turbine to respond to local, short-term changes in wind condition. As wind turbine rotors become larger, control methods that act on a single blade or blade section are increasingly necessary to reduce critical fatigue and extreme loads. However, microjets require power to operate, and thus, it is crucial that the fatigue reduction justifies any energy input to the system. To examine the potential for fatigue reduction of a range of potential microjet system configurations, a blade element momentum (BEM) code and a flow energy solver were used to estimate the energy input and the change in primary fatigue metrics. A parametric analysis was conducted to identify the optimal spanwise position and length of the microjets over a range of air mass flow rates. Both active and passive air supply methods were considered. A passive microjet system applied to the NREL 5-MW rotor produced a 3.7% reduction in the maximum flapwise root bending moment (FRBM). The reduction in the peak bending moment increased to 6.0% with a 5 kPa blower that consumes approximately 0.1% of the turbine output power. The most effective configurations placed microjets between the blade midspan to three-quarters span. Load reduction was achieved for both active and passive modes of air supply to the microjet system.