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The subduction interface geometry is particularly important for estimating interplate coupling and surface geodetic motion, which has significant implications for seismic hazard mapping. Several published Cascadia subduction interface geometries derived from different seismic data sets vary significantly from one another. However, results from deformation models that use the different interface geometries are rarely systematically compared. Here, we assess the impact of subduction interface geometry on surface motion predictions, slip inversion results, and interface coupling estimates from four published Cascadia subduction interface geometries. We isolate the effect of the interface geometry on the predicted surface motion by applying uniform unit slip or Gaussian slip patterns to each interface geometry and calculate the predicted displacements at locations of GNSS stations. The forward model‐predicted horizontal displacements can differ by >20% and show azimuthal differences up to 10°; such differences correlate spatially to geometric differences amongst the interface realizations. Inversions of surface displacements estimated using a Gaussian distribution of slip, mimicking an earthquake, recover the applied slip distribution with differing spatial patterns and residuals of up to 38% of the maximum applied slip. Block models that use the four interface realizations produce coupling estimates on the interface with regions of significant coupling (>50%) that differ noticeably in down‐dip extent and lateral continuity. The results we present suggest that models utilizing interface geometry as an input, such as earthquake and tsunami models, should consider comparing models with differing interface geometries to critically evaluate model uncertainty stemming from this fundamental input. Plain Language Summary Convergent plate boundaries, such as the Cascadia Subduction Zone, host the world's largest earthquakes, posing a significant hazard to nearby populations. Between large earthquakes, stress accumulates as a result of the two converging plates being stuck together (coupled) at their interface (the subduction megathrust). The spatial distribution of this coupling may inform both earthquake and tsunami hazard assessments, as strongly coupled regions are the most likely to fail in a large megathrust earthquake. We can estimate the distribution of coupling using surface motion recorded by GNSS stations between large earthquakes, but this requires an assumption about the subduction interface geometry. For Cascadia, several distinct, plausible interface geometries have been proposed. Because it is difficult to distinguish which interface geometry is the most accurate, understanding the impact of using one interface geometry over another on models that simulate crustal deformation can help constrain model uncertainty. Here, we compare four different interface geometries proposed for Cascadia and find that estimated surface motion and coupling distributions differ across the models. Consequently, earthquake and tsunami simulations that utilize coupling distributions as inputs could be impacted by the choice of subduction interface geometry. Key Points The choice of subduction interface geometry impacts several classes of geophysical models, and their downstream products Interface geometries may differ at short wavelengths, but interseismic geodetic models are more sensitive to the long wavelength structure Block model estimates using different interface geometry vary in down‐dip extent and along‐strike continuity of significant coupling (>50%)

Inversions of interseismic geodetic surface velocities often cannot uniquely resolve the three‐dimensional slip‐rate distribution along closely spaced faults. Microseismic focal mechanisms reveal stress information at depth and may provide additional constraints for inversions that estimate slip rates. Here, we present a new inverse approach that utilizes both surface velocities and subsurface stressing‐rate tensors to constrain interseismic slip rates and activity of closely spaced faults. We assess the ability of the inverse approach to recover slip rate distributions from stressing‐rate tensors and surface velocities generated by two forward models: (a) a single strike‐slip fault model and (b) a complex southern San Andreas fault system (SAFS) model. The single fault model inversions reveal that a sparse array of regularly spaced stressing‐rate tensors can recover the forward model slip distribution better than surface velocity inversions alone. Because focal mechanism inversions currently provide normalized deviatoric stress tensors, we perform inversions for slip rate using full, deviatoric or normalized deviatoric forward‐model‐generated stressing‐rate tensors to assess the impact of removing stress magnitude from the constraining data. All the inversions, except for those that use normalized deviatoric stressing‐rate tensors, recover the forward model slip‐rate distribution well, even for the SAFS model. Jointly inverting stressing rate and velocity data best recovers the forward model slip‐rate distribution and may improve estimates of interseismic deep slip rates in regions of complex faulting, such as the southern SAFS; however, successful inversions of crustal data will require methods to estimate stressing‐rate magnitudes. Key Points Joint inversions of velocity and stressing‐rate data can better estimate slip rates along complex faults than individual inversions Inverting data at multiple depths can better estimate fault locking depth than inverting data at a single depth Application of the new method requires estimates of crustal deviatoric stressing‐rate tensors with magnitude

Parental care occurring after hatching of eggs in precocial birds has been assumed to have no effect on offspring survival because young feed themselves, and behaviour such as vigilance or defence benefits all young regardless of brood size. We tested this assumption by manipulating clutch and brood size of wild mallards (Anas platyrhynchos) and subsequently monitoring survival of ducklings. Offspring survival in enlarged broods tended to be lower than in control broods. By 14 days after hatching, enlarged broods had no more ducklings surviving than did controls. Brooding efficiency (i.e., the effectiveness of heat transfer from a care-giving female to her young) was evaluated with captive mallards in an environmental chamber where we manipulated ambient temperature and brood size, and monitored duckling temperature (T d ). There was no difference in T d in broods of different sizes, but variation in T d increased with brood size. Under natural conditions, the female's inability to effectively cover large broods could reduce duckling survival. Thus, brooding may represent one post-hatching behaviour that could limit clutch size in precocial birds. This study provides new insights regarding the implications of brood size on the survival of precocial young.

Many chemical engineers associate the term safety with preventing runaway reactions and explosions, selecting pressure relief valves and rupture discs, and management of change. Indeed, chemical engineers are uniquely qualified to deal with these important aspects of process safety aimed at preventing large-scale incidents. Occupational safety, on the other hand, is concerned with preventing the employee's exposure to hazards such as the individual chemicals that are being used.

Bald eagle (Haliaeetus leucocephalus) densities vary throughout North America, but reasons for these differences are poorly understood and may be important for directing management practices. Thus, we evaluated the influence of forest nesting habitat and food abundance on the densities of bald eagles on 2 lakes in northcentral Saskatchewan, Canada. We found no evidence that nest-site availability influenced the number of eagles on either lake. Differences in the food supply were investigated both directly by netting fish, and indirectly, through information obtained from biological surveys at Besnard and Nemeiben Lakes. Cisco (Coregonus artedii), a key prey species for eagles, were more common and larger (P < 0.05) in Besnard Lake. Evidence from mineral content, plankton, benthic fauna biomass, and abundance of fish, support the contention that food abundance was the most important factor contributing to density differences of bald eagles between Besnard and Nemeiben Lakes. Food supply should be an integral part of any management plan aimed at protecting or enhancing bald eagle habitat.

Reproductive success in birds often is measured in terms of the proportion of nests that hatch or fledge young. We assessed survival of 35 Mallard (Anas platyrhynchos) broods near Yorkton in east-central Saskatchewan, Canada, from 1990 to 1993. Brood survival was higher for offspring that hatched early in the breeding season in three of four years when wetland abundance declined over the summer. Seasonal patterns of wetland abundance were reversed in 1993, and early hatching broods suffered higher mortality. A more accurate measure of reproductive success is the number of young that survive to breed, i.e. recruitment. Ducklings were tagged at Yorkton and on the St. Denis National Wildlife Area (1985 to 1995), enabling us to identify individuals that returned to breed in subsequent years. Female recruits were more likely to originate from early hatched nests at both sites. With respect to recruitment, we also tested for an additional advantage of hatching early, over and above that associated with duckling survival. There was no statistical difference in the seasonal distribution of nests producing recruits compared with broods that successfully fledged at least one young. Thus, the selective advantage to nesting early for Mallards likely is driven by a seasonal decline in duckling survival, which in turn may be associated with decreasing wetland density.

The deoxyribonuclease (DNase) test is useful in classifying Serratia bacilli and in differentiating it from the Hafnia group, E. cloacae, and E. liquefaciens. It is recommended as a differential test in enteric bacteriology because of its specificity, the convenience of its use, and the rapidity with which it can be performed.

The culture and biochemical features of 10 non-chromogenic variants of S. marcescens isolated from clinical sources are reported. Autoagglutination titres were significantly high in sera from those patients in whom Serratia bacilli appeared to contribute to the illness. Since the taxonomic stature of the Serratia bacilli is not clear it might be better to limit the identification of this group to Serratia species.

In birds that exhibit sexual size dimorphism, hatching asynchrony, and siblicide, the probability of nestling mortality and the cost of rearing young may vary with different combinations of sex and hatching sequence. When food abundance varies spatially and temporally, parents may maximize their fitness by manipulating their primary sex ratio. We examined the sex and hatching order of nestling bald eagles (Haliaeetus leucocephalus) over 17 years on one lake and 5 years on another. The lakes are approximately the same size, but differ dramatically in eagle density and prey abundance. In years when the number of eaglets fledged was high (suggesting higher food abundance), there was a significant bias in the first-hatched chick toward the larger sex (females), and broods with a first-hatched male and a second-hatched female (MF broods) were under-represented. In years with lower productivity, and on the lake with lower food abundance, there was a male-bias in the population sex ratio of nestlings and the first-hatched egg. Variation in sex ratio and hatching order may relate to the probability of siblicide associated with MF broods, or the differential cost of raising the sexes.

In the \"Battle of Athens\" in McMinn County, Tenn., some returning World War II veterans decided they had enough of a corrupt tyrannical county government and did something about it.