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Human stressors block, eliminate, and simplify habitat mosaics, eroding landscapes' life history diversity and thus biological resilience. One goal of restoration is to alleviate human stressors that suppress life history diversity, but life history responses to these efforts are still coming into focus. Here, we report life history diversity emerging in threatened salmonids (Oncorhynchus spp.) repopulating the recently undammed Elwha River (WA, United States) in adjacent but environmentally distinct tributaries. The ~20km tributaries entered the Elwha River <1km apart, but one had a colder stream temperature regime and swifter waters due to its high, snow-dominated elevation and steep valley gradient (~3%), while the other had a warmer stream temperature regime and slower waters because it drained a lake, was at lower elevation, and had a lower stream gradient (~1.5%). Following the 2012 removal of Elwha Dam, the tributaries' salmonids generally became more abundant and expressed diverse life histories within and among species. The warmer, low-gradient tributary produced more age-1+coho salmon and steelhead. Additionally, salmonids exiting the warmer tributary were older and possibly larger for their age class, emigrated ~23 days earlier, and included age-0 Chinook salmon that were larger. Also, assemblage composition varied among years, with the most abundant species shifting between Chinook salmon and coho salmon, while steelhead abundances generally increased but were patchy. These patterns are consistent with a newly accessible, heterogeneous landscape generating life history diversity against the backdrop of patchy recruitment as salmonids -- some with considerable hatchery-origin ancestry -- repopulate an extirpated landscape. Overall, dam removal appears to have promoted life history diversity, which may bolster resilience during an era of rapid environmental change and portend positive outcomes for upcoming dam removals with similar goals. [ABSTRACT FROM AUTHOR]

A new high-saturation induction, high-temperature nanocomposite alloy for high-power inductors is described. The studies have shown that this new alloy can operate at higher flux densities and higher temperatures, thereby reducing the overall size of the inductor.

A new high-saturation induction, high-temperature nanocomposite alloy for high-power inductors is discussed. This material has FeCo with an A2 or B2 structure embedded in an amorphous matrix. An alloy of composition Fe56Co24Nb4B13Si2Cu1 was cast into a 1.10 in. wide, 0.001 in. thick ribbon from which a toroidal core of approximately 4.25 in. outer diameter, 1.38 in. inner diameter, and 1.10 in. tall was wound. The core was given a 2 T transverse magnetic field anneal, and impregnated for strength. Field annealing resulted in a linear B-H response with a relative permeability of 1400 that remained constant up to field strengths of 1.2 T. The core was used to construct a 25 μH inductor for a 25 kW dc-dc converter. The inductor was rated for operation in discontinuous conduction mode at a peak current of 300 A and a switching frequency of up to 20 kHz. Compared to commercially available materials, this new alloy can operate at higher flux densities and higher temperatures, thus reducing the overall size of the inductor. [ABSTRACT FROM AUTHOR]

For more than 100 years, two dams blocked upstream migration of steelheadOncorhynchus mykiss(anadromous Rainbow Trout) on the Elwha River, Washington. Prior to the removal of both dams (completed in 2015), 30 spatiotemporal collections of resident Rainbow Trout, steelhead, hatchery steelhead, and hatchery-derived Rainbow Trout (1,949 individuals) were made from 17 sites in the river, and the pattern of genetic diversity and connectivity were evaluated using 13 microsatellite loci. Wild-origin steelhead spawned below the downstream dam and were genetically distinguishable from upriver (above dam) resident Rainbow Trout (FST= 0.034), and the resident Rainbow Trout segregated into two distinct groups (FST= 0.056). Nonnative-origin hatchery steelhead varied from the indigenous steelhead (FST= 0.029), and the hatchery trout differed from the resident trout (FST= 0.163). Collections of resident Rainbow Trout from the upper portion of the basin were distinguished by lower estimates of genetic variability (He, AR, and A/L) and effective population size compared with resident Rainbow Trout in the middle reaches of the Elwha River. The break between the two trout groups coincided with Rica Canyon, 8 river kilometers upstream from the Glines Canyon Dam (the upstream dam), suggesting that the upper and middle trout groups represent historicO. mykissgroups separated by flow conditions in the canyon prior to dam construction. Anticipating the potential for genetic exchange between steelhead and resident Rainbow Trout following dam removal, we evaluated the ability of the microsatellite baseline to distinguish F1crosses between the life history groups with computer simulations. These results demonstrate how a genetic baseline can be used as a conservation management tool to measure potential genetic introgression among resident populations and recolonizing anadromous populations. Received June 17, 2016; accepted October 10, 2016 Published online December 12, 2016 [ABSTRACT FROM PUBLISHER]