Fourteen-millimeter lateral mass screws (effective length, 11 mm) placed in a superolateral trajectory in the adult cervical spine provide an equivalent strength with a much lower risk of injury than the longer bicortical screws placed in a similar orientation.

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Several approaches to performance assessment for selecting projects for highway infrastructure improvement are synthesized. In a planning cycle, highway agency divisions face many diverse candidates for maintenance and improvements, originating from public demand, accident data, engineering judgment, and local officials. Resources are limited, and selection factors to consider include crash risk reduction, travel time savings, economic development, environmental protection, aesthetics, and capital and maintenance costs. This article describes the adoption of quantitative metrics for some factors, their estimation with varying precision for about 30 actual projects, graphical project comparison, and a related application of multiple factors to interchange design. Identified needs include to (a) select appropriate metrics for diverse projects; (b) coordinate information systems; (c) avoid preassigned factor weighting, enabling juxtaposition of quantitative and qualitative factors and invitation of newfactors in a deliberation; (d) interpret public agency planning for citizens and government officials; (e) appreciate any tort liability of generating risk-related data; and (f) address the impacts on saturated, urban networks.

A fast time response X-ray foil calorimeter has been developed and used to determine the soft-X-ray yield (h nu <850 eV) from plasma produced by 1.75 ns duration Brillouin compressed KrF laser pulses (248 nm). The X-ray conversion was measured for various elements ranging in atomic number from 6 to 82 at an intensity of 5*1012 W cm-2. Assuming a cos theta angular distribution, maximum conversion efficiencies exceed 30% for high-Z targets.