A phase-only method of generating notches in the beam pattern of a phased array antenna is described. It is shown how the problem can be formulated as a semidefinite programming problem, and solved with readily available solvers. Numerical results simulating the performance of a 32 element uniform linear array are presented.

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The University of Vermont is in the process of constructing a new major facility to house various biotechnology research laboratories and offices. This five-storey, 65000 square foot concrete structure, named the Stafford Building, is being equipped with fiber optic and conventional sensors embedded into the concrete superstructure. These sensors will allow monitoring of stresses incurred during t h e construction phase and monitoring of concrete curing as well as vibration sensing and internal crack sensing. Longitudinal studies of the building's in-service performance and overall health will also be carried out. A description of the sensor choices, physical placements, use and review of relevant construction practices are presented in this paper.

Angle glint can be explained as distortions in the radar echo signal phase front, or alternatively, deviations of the direction of power flow from the radial direction. Here we show that these two theories yield identical results when the polarization of the scattered waves and the receiving antenna are considered.

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Three hydrolases from the crude venom of the Malayan pit viper (Akistrodon rhodostoma) can be differentiated. The first, which we designate ARH alpha, is the well-known fibrinogenolytic enzyme ancrod. The second, ARH beta, which has not been described previously, is identified by its electrophoretic mobility after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), by its ability to hydrolyze H-D-phenylalanyl-L-piperyl-L-arginyl-rho-nitroanilide, and by inhibition of its activity by diisopropyl phosphorofluoridate. The third, ARH gamma, also previously not described, has been purified by using gel permeation and ion-exchange chromatography and preparative PAGE. Chemical, electrophoretic, and hydrodynamic data indicate that it is a single-chain, nonglobular glycoprotein with a molecular weight of 25,600. ARH gamma catalyzes the degradation of several plasma vitamin K dependent coagulation factors, including factor IX, factor X, prothrombin, and protein C. The products are electrophoretically similar to factor IXa beta, factor Xa, thrombin, and activated protein C, respectively. However, these products contain little or no enzymatic activity. ARH gamma-degraded factor IX, factor X, prothrombin, and protein C can be subsequently activated by factor XIa, Russell's viper venom X coagulant protein, crude taipan snake venom, and thrombin, respectively. The N-terminal sequence of the peptides resulting from the ARH gamma digest of porcine factor IX shows that at least three bonds are hydrolyzed: (1) at position 152, seven residues from the Arg145-Ala146 factor XIa cleavage site; (2) at position 167 within the factor IX activation peptide; and (3) at position 177, three residues from the Arg180-Val181 factor XIa cleavage site. The degradation of factor IX by ARH gamma is not affected by several serine protease inhibitors. ARH gamma catalyzes the degradation of both the heavy and light chains of porcine factor VIII which results in the inability of thrombin to activate factor VIII. ARH gamma also catalyzes the degradation of porcine antithrombin III which abolishes its ability to inhibit thrombin. These findings may have relevance to studies of hemostatic derangements following envenomation by this snake. Additionally, several novel coagulation factor derivatives have been generated for structure-function studies.

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