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The cause of death for raptors poisoned at illegal carbofuran-laced predator baits is often not confirmed because the carcass matrices that are conventionally analyzed are not available due to decomposition and scavenging. However, many such carcasses retain intact feet that may have come into contact with carbofuran. Eastern screech owls (Otus asio) were exposed to carbofuran via simulated predator baits. Detection of carbofuran from owl feet weathered for 28 days demonstrated the temporal reliability of using feet during a forensic investigation. Raptor carcasses previously not submitted for residue analysis because of a lack of the conventional matrices may now be salvaged for their feet.

Aqueous borohydride is shown to be an effective reagent for hydriding metals and intermetallics. It is the hydriding equivalent of 20-30 atm of H[sub 2]. The reaction is a convenient way to screen materials for hydride formation and possible utility in applications such as nickel-metal hydride batteries. The reaction is also a convenient alternative to decrepitation for the production of free flowing powders. 16 refs., 1 fig., 1 tab.

One approach to increasing the lifetime of the metal hydride electrode has been the use of conventional electroless plating to produce a coating of copper or nickel on the surface of the metal hydride powders. In this paper, a novel method for microencapsulating the active electrode powders is presented. This new plating technique takes advantage of the reducing power of hydrogen already stored inside the metal hydride to plate a variety of metals onto metal hydride materials. This method greatly simplifies electroless plating for these powders, eliminating the need for stabilizers and additives typically required for conventional electroless plating solutions. Metals that can be electrolessly plated with stored hydrogen have been identified based on thermodynamic considerations. Experimentally, micrometers thick coatings of copper, silver, and nickel have been plated on several metal hydrides.

We conducted two laboratory subacute dietary toxicity tests and one outdoor subacute dietary toxicity test to determine the effectiveness of the U.S. Environmental Protection Agency's deterministic risk assessment model for evaluating the potential of adverse effects to birds in the field. We tested technical-grade diazinon and its D.Z.N 50W (50% diazinon active ingredient wettable powder) formulation on Canada goose (Branta canadensis) goslings. Brain acetylcholinesterase activity was measured, and the feathers and skin, feet, and gastrointestinal contents were analyzed for diazinon residues. The dose-response curves showed that diazinon was significantly more toxic to goslings in the outdoor test than in the laboratory tests. The deterministic risk assessment method identified the potential for risk to birds in general, but the factors associated with extrapolating from the laboratory to the field, and from the laboratory test species to other species, resulted in the underestimation of risk to the goslings. The present study indicates that laboratory-based risk quotients should be interpreted with caution.

Migratory white-throated sparrows (Zonotrichia albicollis) were exposed to acephate (acetylphosphoramidothioic acid O, S-dimethyl ester), an organophosphorus pesticide, to determine its effects on migratory orientation and behavior. Birds were also exposed to polarizer sheets to determine the mechanism by which acephate may affect migratory orientation. Adult birds exposed to 256 ppm acephate a.i. were not able to establish a preferred migratory orientation and exhibited random activity. All juvenile treatment groups displayed a seasonally correct southward migratory orientation. We hypothesize that acephate may have produced aberrant migratory behavior by affecting the memory of the migratory route and wintering ground. This experiment reveals that an environmentally relevant concentration of a common organophosphorus pesticide can alter migratory orientation, but its effect is markedly different between adult and juvenile sparrows. Results suggest that the survival of free-flying adult passerine migrants may be compromised following organophosphorus pesticide exposure.

Summary The anaesthetic management of patients undergoing tracheal resection for tracheal stenosis and the advantage of the maintenance of spontaneous respiration without intubation of the distal tracheal segment is discussed. The case reports of two such patients using a continuous intravenous infusion of Althesin with maintenance of spontaneous respiration are presented. The technique expedited the surgical re-anastomosis due to lack of instrumentation in the surgical field. While some mild respiratory depression as evidenced by carbon dioxide retention did occur, the technique is worthy of consideration for the procedure.