Steven R. Sheffield

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There is growing public pressure to minimize the use of vertebrates in ecotoxicity testing; therefore, effective alternatives to toxicity tests causing suffering are being sought. This report discusses alternatives and differs in some respects from the reports of the other three groups because the primary concern is with harmful effects of chemicals at the(More)
Mesocosms have been used in aquatic ecotoxicology for approximately 20 years and were sometimes claimed to be essential tools, especially for regulatory purposes. The term aquatic mesocosm currently describes indoor and outdoor artificial streams or experimental ponds and enclosures. The use of mesocosms refines the classical methods of ecotoxicological(More)
The widespread use of cholinesterase-inhibiting pesticides in the environment presents increasing concerns about their effects on human, wildlife, and ecosystem health. As a group, these pesticides are generally highly toxic and have great potential for negatively affecting nontarget organisms. Small mammals have proven to be ideal biomonitors of(More)
(This is part 2, continued from " Use of harsh Wafer Probing to Evaluate Traditional Bond Pad Structures "). Goals for circuit under pad (CUP) in aluminum – silicon dioxide (Al – SiO 2) based IC pad structures include the design of metal interconnects in all layers beneath the pad Al, and the ability to withstand harsh probing and wirebonding stress without(More)
Foreword Presidents of The Wildlife Society and the Ameri-can Fisheries Society occasionally appoint ad hoc committees to study and report on select conservation issues. These reports ordinarily appear as either a Technical Review or a Position Statement. Review papers present technical information, and position statements are based on these reviews.(More)
IC bond pad structures having Al metallization and SiO 2 dielectric have been traditionally designed with full plates in underlying metallization layers, connected by vias. In addition, pads having bond over active circuitry (BOAC) which are much more sensitive to pad cracks, are likely present in the same IC. Cracks in the pad dielectric weaken the bond(More)
The Great Blue Heron (Ardea herodias) is a colonial breeder exhibiting a moderate to high vulnerability to human disturbance. Habitat destruction and the resulting loss of nesting and foraging sites potentially put this species at risk. Potomac Creek Heronry in Stafford County, Virginia, has been the subject of heightened concern as the pace of local(More)
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