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The Intermontane-Insular terrane boundary stretches over 2000 kilometers from British Columbia to Alaska in the western Cordillera. Juxtaposed between these terranes is a series of Jura-Cretaceous basinal and arc assemblages that record a complicated and contested tectonic evolution related to the Mesozoic-Paleocene accretionary history of northwestern North America. In southwest Yukon, west-verging thrust faults facilitated structural stacking of the Yukon-Tanana terrane over these basinal assemblages, including the Early Cretaceous Blanchard River assemblage. These previously undated compressional structures are thought to be related to the final collapse of the Jura-Cretaceous basins and the tectonic burial of the Blanchard River assemblage resulting in amphibolite facies metamorphism. New in situ U-Th-Pb monazite ages record at least three tectonic events: (1) the tectonic burial of the Blanchard River assemblage to amphibolite facies conditions between 83 and 76 Ma; (2) peak burial was followed by regional exhumation at ca. 70-68 Ma; and (3) intense heating and ca. 63-61 Ma low-pressure contact metamorphism attributed to the intrusion of the voluminous Ruby Range suite, which is part of the northern Coast Mountains batholith. The tectonometamorphic evolution recorded in the Blanchard River assemblage can be correlated to tectonism within southwest Yukon and along the length of the Insular-Intermontane boundary from western British Columbia through southwestern Yukon and Alaska. In southwest Yukon, these results suggest an asymmetric final collapse of Jura-Cretaceous basins during the Late Cretaceous, which relates to the terminal accretion of the Insular terranes as they moved northward.

Evaluating population-level responses to conservation action following large-scale disturbance can improve the efficacy of future habitat conservation measures. In October 2012, Hurricane Sandy storm surges cleared vegetation and opened inlets through the barrier islands, Fire Island and Westhampton Island, New York, creating Piping Plover (Charadrius melodus) habitat. Storm effects prompted an island-wide stabilization project, which had the potential to negatively affect novel Piping Plover habitat. Certain sections of Fire Island were designed to create and/or improve habitat (hereafter, restoration areas) to mitigate possible habitat loss or degradation. Since Piping Plovers in New York appear to be habitat-limited, we anticipated positive population growth following habitat creation. From 2013 to 2018, we captured and banded 152 adults and 353 chicks, and monitored 279 nests and 160 broods. We developed an integrated population model to assess demographic processes in response to hurricane created-habitat (2013–2018) and the creation of restoration areas (2015–2018). We observed positive population growth in 3 of 5 yr, and overall growth throughout the period ( = 1.13). Immigration and reproductive output were correlated with population growth (r = 0.92 [95% CI: 0.22 to 0.98] and 0.84 [95% CI: –0.47 to 0.95], respectively). Compared with the rest of the study area, restoration areas had higher chick survival, and lower nest survival and after second-year site fidelity. The result was population growth in restoration areas ( = 1.14) similar to the whole study area. In the short term, restoration areas seemed to mimic natural Piping Plover habitat. Vegetation removal, an important process in renewing natural Piping Plover habitat, likely will be necessary to maintain habitat suitability. Efforts to increase immigration of new breeding adults into the system, and to improve reproductive output, primarily by habitat creation or maintenance, are likely to have the greatest local effect on population growth.LAY SUMMARYDespite being listed under the Endangered Species Act for more than 30 yr, and intensive management, Piping Plovers on the Atlantic Coast have not met population recovery goals across much of their breeding range.Hurricane Sandy increased available nesting habitat (dry sand) by over 150%. Following Hurricane Sandy, we monitored a population of individually marked birds on Fire Island and West Hampton Island, New York, for 6 yr. The area monitored included restored habitat, to evaluate the effectiveness of Piping Plover targeted habitat management.The population increased 90% in the 6 yr following Hurricane Sandy, primarily because of immigrant adults, and local reproductive success. The reproductive output and population growth in restoration areas were similar to the rest of the study area.Overall, Hurricane Sandy habitat creation was positive for this local plover population.Efforts to allow future hurricane storm surges to create habitat, along with continued management, will improve long-term population persistence.

The Hart River sills are a set of mafic to intermediate intrusions that occur in northern Yukon, Canada. The largest sills are over 500 m thick and over 200 km long. New U-Pb dates of 1382.15 ± 0.39 Ma and 1382.14 ± 0.36 Ma were obtained via chemical abrasion thermal ionization mass spectrometry on zircon. Whole rock initial neodymium isotopic compositions of the Hart River sills are juvenile and have eNdi from +1.5 to +4.0. The primary mineralogy of the Hart River sills is predominated by clinopyroxene and plagioclase. Geochemical modeling indicates that the Hart River sills lie on a common liquid line of descent defined by a fractionating assemblage of plagioclase, clinopyroxene and minor olivine. The Hart River sills have rare earth element and high field strength abundances similar to normal mid-ocean ridge basalts (N-MORB) but are enriched in large ion lithophile elements. The Sm/Yb and Dy/Zr ratios indicate >8% partial melting of spinel-bearing mantle. During the emplacement of the Hart River sills, western Laurentia was juxtaposed with Australia and eastern Antarctica within the supercontinent Columbia. The degree of partial melting, similarity to N-MORB, and juvenile isotopic signature are consistent with an episode of rifting at 1.38 Ga. Coeval magmatism and intracontinental rift basins farther south on Laurentia provide additional evidence for rifting of supercontinent Columbia at 1.38 Ga.

The impact of habitat loss on shorebirds may be exacerbated by disturbance from human recreational use, which further reduces the amount of coastal habitat that is functionally available. This can have consequences for the condition of individual birds or for population processes, both of which should be considered in strategies to reduce conflict between shorebirds and recreational users of coastal habitat. Our objectives were to determine the associations between human recreational use, coastal habitat modifications, and Piping Plover (Charadrius melodus) body condition and demography. We monitored banded Piping Plovers throughout their annual cycle to assess variation in body condition, true survival, and site fidelity related to disturbance regimes in 8 geographically proximate, nonbreeding areas along the southeastern Atlantic Coast of North America from 2012 to 2016. Piping Plovers in disturbed sites were 7% lighter than those in less disturbed sites. Additionally, true annual survival was ...

In response to growing concerns surrounding pollinator health, there have been increased efforts to incorporate wildflower habitat into land management programs, particularly in agricultural systems dependent on bee-mediated pollination. While recommended plant lists abound, there is limited research on which plant species support the greatest bee abundance and diversity. In many farm settings, drought-tolerant plant species adapted to well-drained sandy soils are needed, since wildflower plantings are typically not irrigated. We used a common garden experimental design to evaluate 51 drought-tolerant native perennial plant species, and 2 non-native plant species in three regions of Michigan for their ability to support honey bees (Apis mellifera L. (Hymenoptera: Apidae)) and wild bees. 1,996 honey bees and 2,496 wild bees were recorded visiting study plants. The wild bee community visiting plant species was dominated by Bombus spp. (Hymenoptera: Apidae) (25%), Halictus spp. (Hymenoptera: Halictidae) (23%), and Lasioglossum spp. (Hymenoptera: Halictidae) (16%). The number of honey bees and wild bees visiting study plants varied considerably, suggesting that bee groups have distinct preferences for plant species. Of the plant species assessed, Asclepias syriaca L. (Gentianales: Apocynaceae) (early season), Monarda fistulosa L. (Lamiales: Lamiaceae) (middle season), and Solidago speciosa Nutt. (Asterales: Asteraceae) (late season) were the three most attractive plant species to the entire bee community. Many other plants consistently attracted a high abundance of wild bees, honey bees, or both. Our results inform plant selection to support managed and wild bees as part of pollinator conservation programs in the Great Lakes region of the United States.

Piping Plovers (Charadrius melodus) undertake comparatively short migrations for a shorebird and were not previously thought to congregate in large numbers during migration. Superpopulation size (individuals occurring at the study site during the study period) and stopover duration were estimated for migratory Piping Plovers on South Point, Ocracoke Island, North Carolina, USA, from 3 July–28 October 2016 by integrating a Jolly-Seber model and a binomial model of resighting and count data. We estimated 569 Piping Plovers (95% CI: 502–651) used South Point during fall migration in 2016, approximately 10% of the global population and approximately 15% of the Atlantic Coast population. Stopover duration differed between Piping Plovers that bred on or near our study site (Southern USA, 46 days, SD = 1.7) compared to individuals that bred in the northern area of the breeding range (Atlantic Canada, 41 days, SD = 2.0; New England States, USA, 44 days, SD = 1.8) and the central area of the breeding range (New York and New Jersey, USA, 26 days, SD = 1.4). South Point may be unique in that no other areas are known to host similar numbers of Piping Plovers during fall migration.

Even in the presence of environmental safeguards, catastrophic accidents related to anthropogenic activities occur that can result in both immediate and chronic impacts on local biota. However, due to the unplanned nature of catastrophes, studies aimed to identify the effects of these accidents on an ecosystem and its inhabitants often have imperfect study designs that are reactive rather than proactive, resulting in methodological and analytical challenges. On 20 April 2010, following an explosion on the Deepwater Horizon oil rig, a well blowout occurred on the seafloor approximately 80 km off the Louisiana coast in the Gulf of Mexico. This blowout resulted in the largest marine oil spill in United States history, which impacted critical migratory stopover and overwintering habitat for many seabird and shorebird species, including species of high conservation concern such as the piping plover ( Charadrius melodus ). Here, we assessed the potential longer-term demographic impacts of the Deepwater Horizon oil spill on piping plovers in a capture-mark-recapture framework. We examined whether a series of demographic processes, including probabilities of remaining at a specific wintering site, over-winter and annual apparent survival, winter stopover duration, and abundance varied among oiled and unoiled habitats. We found that the perceived amount of oiling on land, in water, and on individual birds, as well as numerous demographic processes, were spatially or temporally variable. However, we found little support that piping plover demography was negatively influenced by the magnitude of oil observed at an impacted area, or that demographic rates substantially varied between reference and oil impacted areas. Nor did we find that piping plovers that were observed to be oiled had lower survival probabilities following the DWH oil spill relative to non-oiled individuals from the same winter population. Although we did not find that the Deepwater Horizon oil spill substantially influenced piping plovers, our methods provide an analytical framework to more appropriately address both the near or long-term impacts of an anthropogenic disturbance on a species.

Convergent-margin basins (CMBs) are commonly associated with active arcs, and hence are rich in detrital zircon (DZ) whose ages closely reflect the timing of deposition. Consequently, maximum depositional ages (MDA) from DZ geochronology can be employed to resolve the stratigraphy and evolution of CMBs. Herein, we use DZ to revise the internal architecture of the lower Nanaimo Group, which partially comprises the fill of the (forearc) Georgia (or Nanaimo) Basin. Maximum depositional ages and multi-dimensional scaling of DZ age distributions are employed to determine chronologic equivalency of strata and assess sediment provenance variability within the pre-existing lithostratigraphic framework. The results are compared to a recently developed sequence stratigraphic framework for the lower Nanaimo Group. The basal lithostratigraphic unit of the Nanaimo Group, the Comox Formation (Fm), comprises strata that are neither time correlative nor genetically related. The three lithostratigraphic units directly overlying the Comox Fm (Haslam, Extension, and Protection formations) comprise strata with similar genetic affinities and MDAs that indicate deposition of these units was not always sequential and locally was contemporaneous. Through this work, we provide an example of how MDAs from DZ geochronology in CMBs can resolve basin-scale stratigraphic relations, and identify chronological changes in sediment provenance.

Arthropods provide a variety of critical ecosystem services in agricultural landscapes; however, agricultural intensification can reduce insect abundance and diversity. Designing and managing habitats to enhance beneficial insects requires the identification of effective insectary plants that attract natural enemies and provide floral resources. We tested the attractiveness of 54 plant species with tolerance to dry soils, contrasting perennial forbs and shrubs native to the Great Lakes region to selected non-native species in three common garden experiments in Michigan during 2015–2016. Overall, we found 32 species that attracted significantly more natural enemies than associated controls. Among these, Achillea millefolium and Solidago juncea were consistently among the most attractive plants at all three sites, followed by Solidago speciosa, Coreopsis tripteris, Solidago nemoralis, Pycnanthemum pilosum, and Symphyotrichum oolantangiense. Species which attracted significantly more natural enemies at two sites included: Asclepias syriaca, Asclepias tuberosa, Monarda fistulosa, Oligoneuron rigidum, Pycnanthemum virginianum, Dasiphora fruticosa, Ratibida pinnata, Asclepias verticillata, Monarda punctata, Echinacea purpurea, Helianthus occidentalis, Silphium integrifolium, Silphium terebinthinaceum, Helianthus strumosus, and Symphyotrichum sericeum. Two non-native species, Lotus corniculatus, and Centaurea stoebe, were also attractive at multiple sites but less so than co-blooming native species. Parasitic Hymenoptera were the most abundant natural enemies, followed by predatory Coleoptera and Hemiptera, while Hemiptera (Aphidae, Miridae, and Tingidae) were the most abundant herbivores. Collectively, these plant species can provide floral resources over the entire growing season and should be considered as potential insectary plants in future habitat management efforts.

Density-dependent regulation is a fundamental part of ecological theory and a significant driver of animal demography often through complex feedback loops. We investigated the relationship between flood- and demographically induced fluctuations in density and the breeding propensity and survival of a pioneer species, the piping plover (plover, Charadrius melodus).We captured and marked adult and hatchling plovers on the Gavins Point Reach of the Missouri River in South Dakota and Nebraska, USA, from 2005 to 2014. In 2010 and 2011, historically high water levels and flooding inundated much of the plover’s sandbar nesting habitat on theMissouri River.We developed a Bayesian formulation of a multievent model, or a multistate survival model with state uncertainty to estimate breeding propensity simultaneously with survival. Although plovers are conspicuous, their breeding status can be difficult to establish with certainty, which necessitated the use of uncertain states.With this model, we investigated the effect of sex, habitat availability, river flow, and density (birds/ha nesting habitat) on survival of hatch year and breeding and non-breeding adult plovers. In addition, we estimated the transition rates for these age classes between breeding and nonbreeding states. Non-breeding adults (ɸAHY, n = 0.58 ± 0.06) had lower survival rates than breeding adults (ɸAHY, b = 0.80 ± 0.04), and both breeding survival and breeding propensity decreased with increasing nesting density. Not only did survival and breeding propensity decrease directly at higher nest densities, but survival also was indirectly impacted by increasing the proportion of non-breeding birds with relatively low survival. Thus, plovers were regulated through a complex set of feedback loops, acting as densities increased. Our findings underscore the intricacy of density-dependent regulation and suggest that detailed demographic studies are needed to fully understand these effects. Funding was provided by the U.S. Army Corps of Engineers, the U.S. Fish and Wildlife Service, and Virginia Tech.

Quality control (QC) segments conjoined to a bulk sample container are used to evaluate the viability and quality of cryopreserved umbilical cord blood (UCB). Such QC segments are typically attached lengths of sealed tubing that are cooled concurrently with the bulk sample, both containing material from the same donor. QC segments are thawed independently of the bulk sample to assess the quality of the cryopreserved product. In current practice, there is typically post-thaw variation between the QC segment and the bulk sample which if suggestive of inadequate performance, could lead to material being needlessly discarded. In this study, these performance differences were quantified. Two cooling protocols in common use, 1 with and 1 without a "plunge" step to induce ice nucleation, gave equivalent results that maintained the QC segment versus bulk sample differences. Ice nucleated at significantly lower temperatures in the QC segments compared with the bulk samples, a consequence of their lower volume, thereby enhancing damaging osmotic stress. A reduction in total viable cells of approximately 10% was recorded in the QC segments compared with comparable bulk samples. It has been shown that CD45+ cells are more adversely impacted by this lower ice nucleation temperature than CD34+ cells, which can result in altered composition of the post-thaw cell population.

The Lower Cretaceous Viking Formation is a siliciclastic unit that occurs in the subsurface of Alberta in the Western Canadian sedimentary basin. This study focuses on a lowstand paleoshoreline trend extending along strike between two hydrocarbon-producing fields, Joarcam and Judy Creek (250 km NW). The Viking Formation in these fields records depositional thicknesses ranging from 20 to 30 m. Between these two fields, however, the formation is anomalously thick (45–60 m), complicating the recognition and correlation of key stratigraphic surfaces. Marine flooding surfaces above and below the Viking Formation are routinely employed as stratigraphic datums in order to remove postdepositional deformation and facilitate the development of a sequence stratigraphic framework. However, as each successive surface is employed as the datum, the other flooding surfaces within the formation become distorted, resulting in unrealistic depositional geometries. These geometries are best explained to be the result of structural readjustments during Viking deposition. The Precambrian lithosphere of the Canadian Shield forms the Western Canadian sedimentary basin basement, with major structures previously mapped using gravity and magnetic anomaly studies. Locally, the increased accommodation observed within the Viking Formation of central Alberta is attributed to differential reactivation of the Paleoproterozoic Snowbird tectonic zone basement structures, which flank the areas of anomalously thick deposits and trend approximately normal to the regional strike of the Western Canadian sedimentary basin. The Snowbird tectonic zone faults are interpreted to have been reactivated during renewed tectonic loading in the southern Canadian Cordillera during Aptian–Albian time, causing subtle readjustments along basement faults that caused variable syndepositional subsidence. By selecting successive datums, the gross Viking interval can be recognized to have accumulated prior to, during, and following structural reactivation.

Seabird demography and spatial distribution outside of the breeding season are poorly understood, and migratory stopover and staging sites represent important energetic bottlenecks during the avian annual cycle. We quantified hatch-year Roseate Tern (Sterna dougallii) weekly residency, weekly recruitment rate into the staging population, and derived weekly staging population growth rate during two postbreeding, premigratory staging seasons (2014 and 2015) at Cape Cod National Seashore, Massachusetts, USA. We also estimated hatch-year tern stopover duration at Cape Cod staging grounds. Tern residency probability at Cape Cod National Seashore during 2014 and 2015 was nearly 1 during the first weeks of the season and decreased steadily over the last 4 weeks to ~0.5 in the final week of the study. Recruitment rates into the staging population, representing the weekly per capita change in hatch-year terns present during the staging season, indicated that most terns arrived on the staging grounds during the first weeks of the staging season (16 July to 19 August). We also identified differences in staging duration between birds from the two breeding regions. Hatch-year terns from the southernmost region spent less time staging at Cape Cod National Seashore than their northern counterparts in both 2014 and 2015. These differences may indicate alternative staging strategies for individuals originating in different regions and possibly reveal differences in resource conditions between these areas, for example, in the availability of ephemeral prey fish.

Background and Hypothesis: With medical school curriculum changes, students have to reassess how they approach their studies. This study evaluates how medical students planned to study gross anatomy before and after the 2016 Indiana University School of Medicine (IUSM) curriculum change. Student study plans are hypothesized to be different before and after the curriculum change. Methods: First-year medical students from 2015-2017 were given a survey prior to their gross anatomy course. The survey integrated 37 Likert scale questions about resources the students might use, study strategies, demographics, prior anatomy and/or physiology courses, etc. T-tests were run between the curriculum and student grades as well as seven categories that grouped related questions from the survey. Comparisons were also made between the upper and lower thirds of the class. Results: The final course and NMBE percentages were found to be significantly different between curricula (p

The Nonacho Group comprises six formations of continental clastic rocks that were deposited between 1.91 and 1.83 Ga. The Nonacho Group is part of a broader assemblage of conglomerate and sandstone that was deposited atop the Rae craton in response to the amalgamation of Laurentia and supercontinent Nuna, but the details of its tectonic setting are contentious. This paper documents an outlier of Nonacho Group rocks ∼50 km east of the main Nonacho basin. Field observations and LA-ICPMS (laser ablation inductively coupled plasma mass spectrometry) U-Pb detrital zircon geochronology are integrated with previous studies of the main basin to better understand the group’s depositional history, provenance and tectonic setting. The lithology and detrital zircon age spectra of the outlier allow for its correlation to the upper two formations of the Nonacho Group. CA-ID-TIMS (chemical abrasion isotope dilution thermal ionization mass spectrometry) analyses of two fragments of the youngest detrital zircon provide a maximum depositional age of 1901.0 ± 0.9 Ma. A felsic volcanic cobble dated at ca. 2.38 Ga provides evidence of volcanism during the Arrowsmith orogeny. Detrital zircon dates recovered from the outlier (ca. 3.4–3.0, 2.7, 2.5–2.3 and 2.0–1.9 Ga) are consistent with derivation from topography of the Taltson and/or Thelon orogens on the western margin of the Rae craton. Taltson-Thelon (2.0 to 1.9 Ga) aged detritus is only abundant in the upper two formations of the Nonacho Group, marking a change in provenance from the lower formations. This change in provenance may have coincided with a period of renewed uplift and the unroofing of Taltson-Thelon plutons. The detrital zircon provenance and depositional age of the Nonacho Group is consistent with models that link its deposition to the Taltson and/or Thelon orogens. However, tectonism associated with the 1.9 to 1.8 Ga Snowbird and Trans-Hudson orogens to the east could also have affected basin formation or the change in provenance from the lower to upper Nonacho Group. This study highlights the importance of CA-ID-TIMS in establishing accurate and precise maximum depositional ages for sedimentary successions.

Adaptive habitat-selection theory predicts that individuals should use habitats that maximize lifetime fitness. However, trade-offs between life-history stages, environmental variability, and predator–prey dynamics can interact with individual preferences, which may result in individuals selecting suboptimal habitats. Understanding the distinction between adaptive and maladaptive animal use of habitat is central to effective species conservation, because use of maladaptive habitat is counter to conservation objectives. Our objectives were to assess whether habitat characteristics selected by Greater Sage-Grouse (Centrocercus urophasianus) were correlated with increased production of fledged young. We monitored 411 nests and 120 broods from 234 females between 2004 and 2012 in central Nevada, USA. We determined which habitat characteristics were selected as nesting habitat and assessed whether these characteristics influenced nest success and early offspring survival. The relationships between cha...

The distribution of tectonic superstructure across the Shuswap metamorphic complex of southern British Columbia is explained by east-west– trending corrugations of the Okanagan Valley shear zone detachment. Geological mapping along the southern Okanagan Valley shear zone has identified 100-m-scale to kilometer-scale corrugations parallel to the extension direction, where synformal troughs hosting upper-plate units are juxtaposed between antiformal ridges of crystalline lower-plate rocks. Analysis of available structural data and published geological maps of the Okanagan Valley shear zone confirms the presence of ≤40-km-wavelength corrugations, which strongly influence the surface trace of the detachment system, forming spatially extensive salients and reentrants. The largest reentrant is a semicontinuous belt of late Paleozoic to Mesozoic upper-plate rocks that link stratigraphy on either side of the Shuswap metamorphic complex. Previously, these belts were considered by some to be autochthonous, implying minimal motion on the Okanagan Valley shear zone (≤12 km); conversely, our results suggest that they are allochthonous (with as much as 30–90 km displacement). Corrugations extend the Okanagan Valley shear zone much farther east than previously recognized and allow for hitherto separate gneiss domes and detachments to be reconstructed together to form a single, areally extensive Okanagan Valley shear zone across the Shuswap metamorphic complex. If this correlation is correct, the Okanagan Valley shear zone may have enveloped the entire Shuswap metamorphic complex as far east as the east-vergent Columbia River–Slocan Lake fault zones.

Plant phenological processes produce temporal variation in the height and cover of vegetation. Key aspects of animal life cycles, such as reproduction, often coincide with the growing season and therefore may inherently covary with plant growth. When evaluating the influence of vegetation variables on demographic rates, the decision about when to measure vegetation relative to the timing of demographic events is important to avoid confounding between the demographic rate of interest and vegetation covariates. Such confounding could bias estimated effect sizes or produce results that are entirely spurious. We investigated how the timing of vegetation sampling affected the modeled relationship between vegetation structure and nest survival of greater sage‐grouse (Centrocercus urophasianus), using both simulated and observational data. We used the height of live grasses surrounding nests as an explanatory covariate, and analyzed its effect on daily nest survival. We compared results between models that included grass height measured at the time of nest fate (hatch or failure) with models where grass height was measured on a standardized date – that of predicted hatch date. Parameters linking grass height to nest survival based on measurements at nest fate produced more competitive models, but slope coefficients of grass height effects were biased high relative to truth in simulated scenarios. In contrast, measurements taken at predicted hatch date accurately predicted the influence of grass height on nest survival. Observational data produced similar results. Our results demonstrate the importance of properly considering confounding between demographic traits and plant phenology. Not doing so can produce results that are plausible, but ultimately inaccurate.

The increasing use of Bayesian inference in population demography requires rapid advancements in modeling frameworks to approach the rigor and flexibility of the current suite of maximum-likelihood models. We developed an unbiased, Jolly-Seber robust design (JSRD) model that is both accessible and generalizable in a Bayesian hierarchical multistate framework. We integrated band and age-classification data to estimate site entry, temporary emigration, and apparent survival rates, as well as estimate age-class specific abundances. The complete model parameterization is provided in the Appendix S1, as well as tools for simulating capture histories and an assessment of model fit. We applied this model to determine whether these demographic processes in non-breeding population of American oystercatchers (Haematopus palliatus) were affected by a major hurricane event (Hurricane Matthew) in coastal Georgia. The JSRD model was demonstrably unbiased at relatively small sample sizes, and the majority of parameters were identifiable in the fully saturated model parameterization. In the model application, we found that Hurricane Matthew temporarily altered local population abundances of American oystercatchers through increased movements of individuals into and out of the observable population, but mortality rates were largely unaffected. Together, our results suggest that American oystercatchers were largely able to avoid the immediate demographic consequences (i.e., reduced survival) of Hurricane Matthew. Integrating age and band ratios from survey data allowed for more descriptive and potentially less biased estimates of age-specific abundance, relative to estimates generated solely from either mark-resight or survey data. National Fish and Wildlife Foundation Georgia Department of Natural Resources Virginia Polytechnic Institute and State University Virginia Tech's Open Access Subvention Fund Funding for this study was provided by the National Fish and Wildlife Foundation, Georgia Department of Natural Resources, and Virginia Polytechnic Institute and State University. We thank two anonymous reviewers for their comments on an earlier draft of this manuscript. We thank the Virginia Tech's Open Access Subvention Fund for providing funds for publication costs. We also thank G. DiRenzo for providing useful code.

NK cells play a key role in innate elimination of virally infected or neoplastic cells but they can be circumvented by immunoevasive mechanisms enabling viral spread or tumor progression. Engagement of the NKG2D activating receptor with soluble forms of its ligand is one such mechanism of inducing NK cell hyporesponsiveness. Interestingly, this immunoevasive strategy among others is described at the maternal-fetal interface where tolerance of the semi-allogeneic fetus is required to allow successful human pregnancy. Understanding of maternal-fetal tolerance is increasing but mechanisms preventing alloreactivity of fetal immune cells against the maternal host are less well understood. The study of umbilical cord blood has enabled insight of the fetal immune system, which appears immature and inert. We have found that soluble NKG2D ligands (sNKG2DLs) are present in cord blood plasma (CBP) and associate with adult NK cell hyporesponsiveness demonstrated by reduced CD107a expression and secretion of IFN-γ upon stimulation. The capacity of NK cells to kill K562 cells or proliferate was also reduced by incubation with CBP; however, physical removal of sNKG2DL from CBP restored K562 lytic function and NKG2D expression. Therefore, our results strongly suggest sNKG2DLs are expressed in CBP as a mechanism of fetal-maternal tolerance in human pregnancy.

Researchers have long recognized that the process of observing nests may influence nest success by increasing depredation risk or causing females to abandon nests. The effects of observer-related nest abandonment may also reduce estimates of daily nest survival when time to nest fate is reduced and the average nest exposure period within the sample becomes shorter. We used an 8-yr record of observer visitations of nesting female Greater Sage-Grouse (Centrocercus urophasianus) in central Nevada, USA, to assess whether observers influenced either the probability of daily nest survival or the overall probability of nest success. Because nest success is influenced by factors other than visitation, we also accounted for the overall quality of a nest (i.e. probability of success in the absence of observer effects) based on potential confounding factors. Nest visitation (no flushing) had no effect on daily nest survival, regardless of nest quality or female age. Flushing a female from a nest substantial...

Monoclonal antibodies of the IgG2 and IgG4 isotype were found to exhibit an increased propensity for displaying two-peak elution profiles during cation exchange chromatography. In some cases, this two-peak elution profile also resulted in the formation of non-reversible mAb aggregates. Comparison of IgG1, IgG2, and IgG4 molecules with the same variable region reveals that the two-peak behaviour is predominantly mediated by the constant region and most likely the lower CH1, hinge and upper CH2 regions of the mAb. Furthermore, comparison of the behaviour of two different IgG4 molecules, reveals that the degree of non-reversible aggregate formation, whilst facilitated by the isotype format, is mediated primarily by the variable region of the molecule. As well as the properties of the mAb molecule itself, the chemistry and structure of the cation exchange resin was also found to have an effect, with the two-peak elution profile being more pronounced with polymer-grafted resins such as Capto S Impact and Eshmuno CPX. These results combined support the theory that binding of IgG2 and IgG4 mAbs to cation exchange resins usually occurs through at least two mechanisms mediated by the structural features of the constant region of IgG2s and IgG4s. One of these mechanisms is not only stronger than the other, but also can lead to a conformational change in the molecule. This conformational change can occur in both variable and constant domains of the antibody. This transitory unfolded state can in turn lead to non-reversible aggregation of some mAb molecules.

Animal resource requirements differ among life-history stages, and thus, habitat is most appropriately thought of as specific to a particular life stage. Accordingly, different habitats may vary in their significance as functions of (1) the sensitivity of population growth to the life stage for which the habitat is most important, (2) spatial association of each habitat to other habitats, and (3) the abundance of the habitat in question. We used an analogy to a life-table response experiment to develop spatial models linking key habitats to rates of population increase in Greater Sage-grouse. We parameterized models linking demographic rates to vegetation and physical attributes of habitats, including spatial association of some habitats to others, using a decade-long study of Greater Sage-grouse in central Nevada. We modeled the contribution of each pixel in the landscape to regional k (finite rate of population increase) using functional relationships between demographic rates and the attributes of that pixel, and the sensitivity of k to each demographic rate. We incorporated the following demographic rates into our model: female nesting success, survival of chicks from hatching to 45 d, and adult female annual survival. We also incorporated the probability a site was used for nesting. Chick survival (62%) and nest site selection (21%) explained most of the variance in lambda. We found that only similar to 8% of all habitat for Greater Sage-grouse contributed to lambda > 1. Habitat supporting population growth occurred in mid-high elevation areas with moderate slopes, and a high percent cover of sagebrush, and in nesting areas close to late-brood habitat. Our models indicate that a relatively small proportion of habitat available to Greater Sage-grouse in central Nevada is responsible for maintenance of the population in our study system. We suggest that the general approach we describe here can be used to improve understanding of habitats most likely to regulate populations in other systems, providing an important tool in ecology and conservation. Nature Conservancy Nevada Agricultural Experiment Station Funding was provided through a contract with the Nature Conservancy. J. Sedinger was supported by the Nevada Agricultural Experiment Station. We thank all individuals and organizations involved with sagegrouse research in Eureka County, as acknowledged in Gibson (2015). We would also like to thank Tom Dilts for all of his help with the use of ArcMap.

Prebreeding survival is an important life history component that affects both parental fitness and population persistence. In birds, prebreeding can be separated into pre- and postfledging periods; carryover effects from the prefledging period may influence postfledging survival. We investigated effects of body condition at fledging, and climatic variation, on postfledging survival of radio-marked greater sage-grouse (Centrocercus urophasianus) in the Great Basin Desert of the western United States. We hypothesized that body condition would influence postfledging survival as a carryover effect from the prefledging period, and we predicted that climatic variation may mediate this carryover effect or, alternatively, would act directly on survival during the postfledging period. Individual body condition had a strong positive effect on postfledging survival of juvenile females, suggesting carryover effects from the prefledging period. Females in the upper 25th percentile of body condition scores had a postfledging survival probability more than twice that (Φ = 0.51 ± 0.06 SE) of females in the bottom 25th percentile (Φ = 0.21 ± 0.05 SE). A similar effect could not be detected for males. We also found evidence for temperature and precipitation effects on monthly survival rates of both sexes. After controlling for site-level variation, postfledging survival was nearly twice as great following the coolest and wettest growing season (Φ = 0.77 ± 0.05 SE) compared with the hottest and driest growing season (Φ = 0.39 ± 0.05 SE). We found no relationships between individual body condition and temperature or precipitation, suggesting that carryover effects operated independently of background climatic variation. The temperature and precipitation effects we observed likely produced a direct effect on mortality risk during the postfledging period. Conservation actions that focus on improving prefledging habitat for sage-grouse may have indirect benefits to survival during postfledging, due to carryover effects between the two life phases.

The average number of eggs in a clutch and the size of those eggs play a role in individual fitness. We explored sources of variation in egg allocations of female Greater Sage-Grouse (Centrocercus urophasianus) in the American Great Basin over a 10-yr period, as well as range-wide variation in clutch size, using our data and other published values. We tested for environmental and individual effects on clutch size (n = 390) and egg volume (n = 2,486) in a mixed-modeling framework, with random-effect terms that described variation among individual females (i.e. heterogeneity) and allowed us to calculate repeatability for clutch and egg size. The strongest influence on clutch size was the timing of nest initiation, which varied by as much as 67 days within years and showed a negative linear relationship with clutch size. Once this pervasive effect was accounted for, we also found positive effects of annual precipitation and nest-site elevation. In wetter years and at more productive high-elevation s...

Males in lek mating systems tend to exhibit high fidelity to breeding leks despite substantial evidence of skewed mating success among males. Although movements between leks are often reported to be rare, such movements provide a mechanism for an individual to improve lifetime fitness in response to heterogeneity in reproductive conditions. Additionally, estimates of apparent movements among leks are potentially biased due to unaccounted variation in detection probability across time and space. We monitored breeding male Greater Sage-grouse Centrocercus urophasianus on 13 leks in eastern Nevada over a 10-year period, and estimated movement rates among leks using capture-mark-recapture methods. We expected that male movement rates among leks would be low, despite predictions of low breeding success for most males, and that detection rates would be highly variable among leks and years. We used a robust design multistate analysis in Program mark to estimate probability of movements among leks, while accounting for imperfect detection of males. Male Sage-grouse were extremely faithful to their leks; the annual probability of a male moving away from its original lek of capture was approximately 3% (se = 0.01). Detection probabilities varied substantially among leks (range = 0.21–0.95), and among years (range = 0.30–0.76), but remained relatively constant within years at each lek. These results suggest that male Sage-grouse dispersal is either rare, or consists primarily of dispersal of sub-adults from their natal areas prior to the breeding season. The study highlights the benefits of robust design multistate models over standard ‘live-encounter’ analyses, as they not only permit estimation of additional parameters, such as movement rates, but also allow for more precise parameter estimates that are less sensitive to heterogeneity in detection rates. Additionally, as these data were collected using capture-mark-recapture methods, our approach to estimating movement rates would be beneficial in systems where radiotagging is detrimental to the study organism.

The mortality process is a key component of avian population dynamics, and understanding factors that affect mortality is central to grouse conservation. Populations of greater sage-grouse Centrocercus urophasianus have declined across their range in western North America. We studied cause-specific mortality of radio-marked sage-grouse in Eureka County, Nevada, USA, during two seasons, nesting (2008-2012) and fall (2008-2010), when survival was known to be lower compared to other times of the year. We used known-fate and cumulative incidence function models to estimate weekly survival rates and cumulative risk of cause-specific mortalities, respectively. These methods allowed us to account for temporal variation in sample size and staggered entry of marked individuals into the sample to obtain robust estimates of survival and cause-specific mortality. We monitored 376 individual sage-grouse during the course of our study, and investigated 87 deaths. Predation was the major source of mortality, and account...

Monitoring of birds often requires the use of very-high-frequency radios or satellite telemetry to enhance detectability of individuals. An assumption implicit in such studies is that radio-marked individuals are representative of the population at whole, which requires that radios do not influence an individual's behavior or demographics. We present results from a capture—mark—recapture study of male Greater Sage-Grouse (Centrocercus urophasianus), some radio collared, others only banded, in an experimental framework to assess whether radio collars influenced the birds' behavior or survival. We generated encounter histories of 906 male Greater Sage-Grouse and used a robust-design framework in program Mark to estimate probabilities of annual survival, detection, and temporary emigration from the lek for the radio-collared and banded segments of the sample population. Results of models suggested that seasonal detection rates at leks the year after capture were 3–5 times higher for males only band...

The Wernecke igneous clasts consist of blocks of plutonic and volcanic rock that range up to hundreds of metres in size. These clasts occur exclusively within zones of hydrothermal breccia (Wernecke Breccia) which are widespread in central and northern Yukon. The breccia zones are hosted by the Wernecke Supergroup and have been dated by U–Pb titanite at 1599 Ma. Four U–Pb zircon ages on the Wernecke igneous clasts (1714–1706 Ma) demonstrate that the clasts are older than the Wernecke Supergroup (

The period of growth prior to fledging is a critical life stage for most birds, and shifts in diet during ontogeny may affect growth and development. We used nitrogen (δ15N) stable isotopes in feather tissue to quantify dietary composition and evaluate the relationship between diet and growth in prefledging Greater Sage-Grouse (Centrocercus urophasianus). Sequential sampling of δ15N from feather tissue that was synthesized throughout growth allowed us to evaluate changes in plant versus invertebrate contributions to chick diet during the first 28 days posthatch. Feathers became depleted in δ15N throughout growth, and Bayesian mixing models suggested that the proportional contribution of invertebrate nitrogen declined with chick age. We estimate that invertebrate contributions to the protein in chick diets decreased from 39% at 1 week to 23% at 4 weeks of age, which is consistent with previous research on sage-grouse that used traditional diet-sampling methods. Chicks with feather δ15N values tha...

a b s t r a c t The reconstruction of the paleocontinental configuration involving ancestral North America (Laurentia) at the Paleoproterozoic-Mesoproterozoic boundary has been developed in the last 30 years with differ- ent scenarios being proposed and different combinations of landmasses assembled together. However, the lack of information for the northwestern side of the North American craton has so far been an obsta- cle for the complete paleocontinental reconstruction and its tectonic history. Here we provide new age determinations on rocks of the Wernecke Supergroup and of the Wernecke Breccia of the Wernecke Mountains in Yukon to provide a more complete picture of the entire North American craton and its pos- sible conterminous at 1600 Ma. The six youngest U-Pb ages of the detrital zircon from quartz sandstones of the Wernecke Supergroup suggest that the sedimentary succession is as old as 1640 Ma. Lu-Hf garnet ages on garnet bearing schists of the Fairchild Lake Group (lower Wernecke Supergroup) give a bimodal population of ages of approximately 1600 Ma and 1370 Ma: the first age is related to the Racklan Orogeny, and the younger event is likely attributable to a reheating episode (Hart River Sills emplacement). The younger age of the Wernecke Supergroup puts into question the previous model concerning the emplace- ment of the Bonnet Plume River Intrusions, and requires the development of a new tectonic model for the northwestern margin of Laurentia. This new model involves obduction of an exotic terrane on top of the Wernecke Supergroup during the latest phases of the Racklan Orogeny (ca. 1600 Ma). This exotic terrane, herein called Bonnetia, contains rocks of the Bonnet Plume River intrusions and of the Slab vol- canics. During the hydrothermal event that led to the emplacement of the Wernecke Breccia, clasts and megaclasts of the overlying Bonnetia foundered down to the breccia pipes to the level of the Wernecke Supergroup, and this dynamic explains the existence of older rocks engulfed within a younger sedimen- tary succession. The Racklan Orogeny is now interpreted as a northwestern expression of the Mazatzal Orogeny of southwestern United States, and of the Labradorian Orogeny of eastern Canada which was in turn connected with the Gothian Orogeny of Scandinavia. The connection among these orogenic events makes plausible the hypothesis of a circum-Laurentian orogenic belt with possible extensions in other landmasses (Australia, Antarctica, Siberia, or China) where coeval deformation belts are present.

A potent anti-vascular endothelial growth factor (VEGF) biologic and a compatible delivery system were co-evaluated for protection against wet age-related macular degeneration (AMD) over a 6month period following a single intravitreal (IVT) injection. The anti-VEGF molecule is dimeric, containing two different anti-VEGF domain antibodies (dAb) attached to a human IgG1 Fc region: a dual dAb. The delivery system is based on microparticles of PolyActive™ hydrogel co-polymer. The molecule was evaluated both in vitro for potency against VEGF and in ocular VEGF-driven efficacy models in vivo. The dual dAb is highly potent, showing a lower IC50 than aflibercept in VEGF receptor binding assays (RBAs) and retaining activity upon release from microparticles over 12months in vitro. Microparticles released functional dual dAb in rabbit and primate eyes over 6months at sufficient levels to protect Cynomolgus against laser-induced grade IV choroidal neovascularisation (CNV). This demonstrates proof of concept for delivery of an anti-VEGF molecule within a sustained-release system, showing protection in a pre-clinical primate model of wet AMD over 6months. Polymer breakdown and movement of microparticles in the eye may limit development of particle-based approaches for sustained release after IVT injection.

BACKGROUND AND PURPOSE: The initial angiographic occlusion rate is the strongest predictor of later rebleeding in previously ruptured coil-embolized cerebral aneurysms. Angiographic estimations of aneurysmal occlusion rates are, however, subjective in nature and confounded by methodologic problems. COR has been developed, and its superiority has been experimentally established to overcome subjective bias. The purpose of this study was to assess the clinical value of COR as a more objective predictor of aneurysm rebleeding when compared with SOR as described in the Raymond Classification. MATERIALS AND METHODS: We applied COR in a consecutive series of 249 patients. Two DSA projections were selected independently by 2 blinded investigators. In cases of disagreement on the selected projections, a consensus decision was obtained. SOR were determined by 2 independent observers according to the Raymond classification. COR was measured by 2 blinded investigators. Interobserver variations were determined for SOR and COR. COR results were compared with SOR results and stratified as 100%, 99.9%–90%, 89.9%–70%, and