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Arrowtooth flounder was found to be a suitable raw material for the production of surimi. Based on SDS-PAGE and autolysis tests, proteolytic activity was not observed during the production process itself, and the 12% residual activity in the mince after washing was effectively inhibited by bovine plasma powder, egg white and a2 macroglobulin. Plasma and egg white continued to increase gel strength values when added at levels higher than necessary to prevent proteolytic activity according to punch test results. Neither carrageenan nor whey protein concentrate were effective as either a protease inhibitor or gel enhancer.

Sodium dodecyl sulfate gel electrophoresis revealed rapid proteolytic degradation of myosin heavy chain in heated arrowtooth flounder muscle. A proteolytic enzyme of approximately 32,000 molecular weight was extracted from the muscle and purified 125 fold. Activity of the semi-purified enzyme at 55°C was optimal against casein at pH 6.0-7.0. Incubation with chemical reagents indicated the involvement of sulfhydryl groups in enzyme activity.

The authors have achieved a 2.488 Gb/s, 318 km repeaterless transmission without any fiber dispersion penalty through a nondispersion-shifted fiber in a direct detection system. The system was loss limited with a T-R power budget of 57 dB. Three key components enabled the authors to achieve this result: (1) a Ti:LiNbO/sub 3/ external amplitude modulator enabling a dispersion-free transmission, (2) erbium-doped fiber amplifiers increasing the transmitting power to +16 dBm, and (3) an erbium-doped fiber preamplifier enabling a high-receiver sensitivity of -4.1 dBm for 10/sup -9/ BER. To the author's knowledge, this result is the longest repeaterless transmission span length ever reported for direct detection at this bit rate. From the experimental results and a theoretical model, the authors identified the sources of the receiver sensitivity degradation from the quantum limit (-48.6 dBm) and estimated the practically achievable receiver sensitivity of approximately -44 dBm ( approximately -124 photons/bit) for 2.5 Gb/s optical preamplifier detection. >

The role of citizens’ groups in advising industry and government regulators has increased steadily in the United States over the past two decades. Prior to the T/V Exxon Valdez oil spill (EVOS) in 1989, various citizens groups expressed increasing concern about complacency and lax regulation by oil shippers and regulators but their attempts to form citizen advisory groups were unsuccessful. On March 29, 1989, T/V Exxon Valdez ran aground on Bligh Reef spilling 40 million liters of crude oil into the waters of Prince William Sound. The incident changed forever how crude oil is transported in the United States. Among other changes, The Oil Pollution Act (OPA) of 1990 established two industry-funded Regional Citizens’ Advisory Councils (RCACs). One is designated for Prince William Sound (PWS) and the downstream regions affected by EVOS. The other was for Cook Inlet (CI) and downstream communities. Both RCACs are non-profit corporations with Boards of Directors representing both the governmental and other stakeholder entities within their region, and the various regulatory entities as ex-officio members. The member entities of both RCACs include tourism, recreational user, and environmental groups as well as commercial fishing and aquaculture interests. The governmental entities in CIRCAC represent a much larger, more urban population than those in PWSRCAC. Also four board seats in PWSRCAC represent primarily Alaska Native interests while CIRCAC has one. Cook Inlet and PWS are very different bodies of water which present different challenges to the safe transport of crude oil. The oil producing and transportation facilities within the areas of responsibility of the two RCACs are also quite different. CIRCAC is concerned with offshore production as well as transportation by multiple funding entities. PWSRCAC is better funded with more focused responsibilities. The two RCACs collaborate on projects of mutual interest, such as geographical response strategies, ports of refuge, and shore zone mapping. They have chosen different paths regarding environmental monitoring, issues, and regulations more specific to their regions of interest.

A repeaterless transmission experiment through 160 km of non-dispersion-shifted fiber at bit rate of 2.5 Gb/s is reported. A direct-current-modulated distributed-feedback laser in conjunction with an erbium-doped fiber amplifier for power amplification constitute the transmitter. The regenerator includes the conventional APD photodetector and the subsequent amplifiers and timing recovery circuit. With careful decision level and laser bias adjustment, less than 0.6 dB of overall system degradation is incurred in this simple system configuration. >

Recent studies on the cytochrome P-450-containing enzyme system of liver microsomes have shown that the cytochrome is present as a number of distinct isozymes, one of which is induced in vivo by the administration of aromatic hydrocarbons, as well as several forms which are less well characterized and not known to be inducible. The various cytochromes exhibit partially selective but overlapping activities with a variety of substrates. Additional components are NADPH-cytochrome P-450 reductase, which binds to the cytochrome to form a tight 1:1 complex, phosphatidylcholine, and cytochrome b5, the role of which is still not clear. Recent evidence indicates that some of the components are mutually beneficial in favoring formation of a functional complex. For example, phosphatidylcholine enhances the binding of substrate and reductase to P-450LM2, reductase enhances the binding of phosphatidylcholine, and substrate (benzphetamine) facilitates the binding of reductase. The possible effect of ethanol on these interactions should be considered in evaluating the reported inhibition by high concentrations of ethanol of reactions catalyzed by liver microsomal cytochrome P-450.