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Isolation and cohesion are two key network features, often used to predict outcomes like mental health and deviance. More cohesive settings tend to have better outcomes, while isolates tend to fare worse than their more integrated peers. A common assumption of past work is that the effect of cohesion is universal, so that all actors get the same benefits of being in a socially cohesive environment. Here, we suggest that the effect of cohesion is universal only for specific types of outcomes. For other outcomes, experiencing the benefits of cohesion depends on an individual's position in the network, such as whether or not an individual has any social ties. Network processes thus operate at both the individual and contextual level, and we employ hierarchical linear models to analyze these jointly to arrive at a full picture of how networks matter. We explore these ideas using the case of adolescents in schools (using Add Health data), focusing on the effect of isolation and cohesion on two outcomes, school attachment and academic engagement. We find that cohesion has a uniform effect in the case of engagement but not attachment. Only non-isolates experience stronger feelings of attachment as cohesion increases, while all students, both isolates and non-isolates, are more strongly engaged in high cohesion settings. Overall, the results show the importance of taking a systematic, multi-level approach, with important implications for studies of health and deviance. [ABSTRACT FROM AUTHOR]

Throughout North America, indigenous women experience higher rates of intimate partner violence and sexual violence than any other ethnic group, and so it is of particular importance to understand sources of support for Native American women. In this article, we use social network analysis to study the relationship between social integration and women's access to domestic violence support by examining the recommendations they would give to another woman in need. We ask two main questions: First, are less integrated women more likely to make no recommendation at all when compared with more socially integrated women? Second, are less integrated women more likely than more integrated women to nominate a formal source of support rather than an informal one? We use network data collected from interviews with 158 Canadian women residing in an indigenous community to measure their access to support. We find that, in general, less integrated women are less likely to make a recommendation than more integrated women. However, when they do make a recommendation, less integrated women are more likely to recommend a formal source of support than women who are more integrated. These results add to our understanding of how access to two types of domestic violence support is embedded in the larger set of social relations of an indigenous community. [ABSTRACT FROM AUTHOR]

Recent studies have shown that Salmonella shedding status affects sows' microbiota during gestation and that these modifications are reflected in the faecal microbiota of their piglets at weaning. The aims of this study were: (a) to evaluate the persistence, up to the fattening period, of the previously measured link between the microbiota of piglets and their mothers' Salmonella shedding status; and (b) measure the impact of the measured microbiota variations on their Salmonella excretion at this stage. To achieve this, 76 piglets born from 19 sows for which the faecal microbiota was previously documented, were selected in a multisite production system. The faecal matter of these swine was sampled after 4 weeks, at the fattening stage. The Salmonella shedding status and faecal microbiota of these animals were described using bacteriological and 16S rRNA gene amplicon sequencing respectively. The piglet digestive microbiota association with the Salmonella shedding status of their sows did not persist after weaning and did not affect the risk of Salmonella excretion during fattening, while the birth mother still affected the microbiota of the swine at fattening. This supports the interest in sows as a target for potentially transferrable microbiota modifications. [ABSTRACT FROM AUTHOR]

Network concepts are often used to characterize the features of a social context. For example, past work has asked if individuals in more socially cohesive neighborhoods have better mental health outcomes. Despite the ubiquity of use, it is relatively rare for contextual studies to use the methods of network analysis. This is the case, in part, because network data are difficult to collect, requiring information on all ties between all actors. In this article the authors ask whether it is possible to avoid such heavy data collection while still retaining the best features of a contextual-network study. The basic idea is to apply network sampling to the problem of contextual models, in which one uses sampled ego network data to infer the network features of each context and then uses the inferred network features as second-level predictors in a hierarchical linear model. The authors test the validity of this idea in the case of network cohesion. Using two complete data sets as a test, the authors find that ego network data are sufficient to capture the relationship between cohesion and important outcomes, such as attachment and deviance. The hope, going forward, is that researchers will find it easier to incorporate holistic network measures into traditional regression models. [ABSTRACT FROM AUTHOR]

Aim: To observe the transfer of the digestive microbiota from sow to piglet, describe the impact of the sow's Salmonella shedding on this transfer and identify transferred populations that could be associated with the future Salmonella status of the piglets. Methods and Results: Salmonella shedding status of 19 sows was determined at the beginning and end of gestation. Four piglets were randomly selected from each sow. Using MiSeq, the microbiotas of the sows at the end of gestation and of their piglets 1 day before weaning were described. Results showed that the Salmonella shedding of the sows, the birth mother, the lairage room, the parity and the contamination of the lairage environment were associated to the microbiota of the piglets (permanova P < 0·05). Several genera were associated with piglets born from negative or positive sows. Conclusion: There is a link between the microbiota of the sows at the end of gestation and the microbiota of their piglets at weaning, and the Salmonella shedding of the sow is associated with the microbiota of the piglets. Significance and Impact of the Study: Salmonella status of the sows affects the microbiota of their piglets and could affect the long‐term Salmonella colonization resistance of these animals and their health. [ABSTRACT FROM AUTHOR]

The rheology of particle suspensions has been extensively explored in the case of a simple shear flow, but less in other flow configurations which are also important in practice. Here we investigate the behavior of a suspension in a squeeze flow, which we revisit using local pressure measurements to deduce the effective viscosity. The flow is generated by approaching a moving disk to a fixed wall at constant velocity in the low Reynolds number limit. We measure the evolution of the pressure field at the wall and deduce the effective viscosity from the radial pressure drop. After validation of our device using a Newtonian fluid, we measure the effective viscosity of a suspension for different squeezing speeds and volume fractions of particles. We find results in agreement with the Maron–Pierce law, an empirical expression for the viscosity of suspensions that was established for simple shear flows. We prove that this method to determine viscosity remains valid in the limit of large gap width. This makes it possible to study the rheology of suspensions within this limit and therefore suspensions composed of large particles, in contrast to Couette flow cells which require small gaps. [ABSTRACT FROM AUTHOR]

In the United States, girls and boys have similar science achievement, yet fewer girls aspire to science careers than boys. This paradox emerges in middle school, when peers begin to play a stronger role in shaping adolescent identities. We use complete network data from a single middle school and theories of gender, identity, and social distance to explore how friendship patterns might influence this gender and science paradox. Three patterns highlight the social dimensions of gendered science persistence: (1) boys and girls do not differ in self-perceived science potential and science career aspirations; (2) consistent with gender-based norms, both middle school boys and girls report that the majority of their female friends are not science kinds of people; and (3) youth with gender-inconsistent science aspirations are more likely to be friends with each other than youth with gender normative science aspirations. Together, this evidence suggests that friendship dynamics contribute to gendered patterns in science career aspirations. [ABSTRACT FROM AUTHOR]

The Eurasian genotype of common reed P hragmites australis subsp. australis is rapidly invading freshwater marshes in North America. Several bird species depend upon particular plant assemblages for feeding and reproduction and could be adversely affected by the expansion of this invader. The objective of this study was to evaluate the effect of common reed on the abundance, richness, diversity and site occupancy of bird assemblages in freshwater marshes recently invaded by the plant (southern Quebec, Canada). We conducted fixed-distance point counts for songbirds (passerines and rails) and visual surveys for waterbirds (ducks, geese and waders) during two nesting seasons (2009 and 2010). There were major structural differences between common reed stands and marsh vegetation assemblages dominated by other plant species (bulrushes, cattails, sedges). However, there was a little difference in abundance, richness, diversity and site occupancy for songbirds. Marsh wren C istothorus palustris, a wetland specialist, was the only nesting bird that preferred a native plant (cattail) over common reed, probably because common reed stands have low plant diversity and few appropriate nest materials. No major differences were observed in the abundance of waterbirds between invaded and non-invaded marshes. For most bird species, the water depth of the marsh had more influence on the abundance of individuals and on site occupancy than the composition of the plant assemblage. Common reed stands can therefore be used by generalist and specialist marsh passerines as feeding and reproduction sites. However, it is possible that in southern Quebec, the number and extent of common reed populations have not yet reached a threshold beyond which adverse effects of the invader on avian species could be significant. This study adds to a growing body of evidence showing that the relationship between invasive plants and birds is not straightforward. [ABSTRACT FROM AUTHOR]

Mobility and irruptive movements have been proposed as mechanisms that could allow some diet specialists to inhabit and breed in environments with highly unpredictable resources, like the arctic tundra. The snowy owl, one of the main avian predators of the tundra, is known to specialize on lemmings during the breeding season. These small mammals are also well known for their tremendous spatial and temporal variations in abundance. We examined the spring (pre-breeding, from March to June) movements of snowy owls by tracking 9 breeding females in the Canadian Arctic for up to 3 yr with satellite transmitters. We used state-space modeling to assess searching behavior and measure breeding dispersal distances. We also ascertain lemming abundance at some of the sites used by the marked owls. Tracked owls displayed searching movements for extended periods (up to 108 d) and traveled over large distances (up to 4093 km) each spring. The distance between furthest apart searching areas in a given year averaged 828 km (range 220 to 2433 km). Settlement date, distance between searching areas, traveled distance and the duration of prospecting movements were longer in the year where density of lemmings recorded in the eastern High-Arctic (Bylot Island) was lowest. Nonetheless, snowy owls settled in areas where local lemming abundance was relatively high. Individual breeding dispersal distance between consecutive years averaged 725 km (range 18 to 2224). Overall, the high mobility of female snowy owls allowed these diet specialists to behave as irruptive migrants and to sustain their reproductive activities during consecutive years even under highly fluctuating resources. [ABSTRACT FROM AUTHOR]

Prédation has been suggested to be especially important in simple food webs and less productive ecosystems such as the arctic tundra, but very few data are available to evaluate this hypothesis. We examined the hypothesis that avian predators could drive the population dynamics of two cyclic lemming species in the Canadian Arctic. A dense and diverse suite of predatory birds, including the Snowy Owl (Bubo scandiacus), the Rough-legged Hawk (Buteo lagopus), and the Long-tailed Jaeger (Stercorarius longicaudus), inhabits the arctic tundra and prey on collared (Dicrostonyx groenlandicus) and brown (Lemmus trimucronatus) lemmings during the snow-free period. We evaluated the prédation pressure exerted by these predators by combining their numerical (variation in breeding and fledgling numbers) and functional (variation in diet and daily consumption rates) responses to variations in lemming densities over the 2004-2010 period. Breeding density and number of fledglings produced by the three main avian predators increased sharply without delay in response to increasing lemming densities. The proportion of collared lemmings in the diet of those predators was high at low lemming density (both species) but decreased as lemming density increased. However, we found little evidence that their daily consumption rates vary in relation to changes in lemming density. Total consumption rate by avian predators initially increased more rapidly for collared lemming but eventually leveled off at a much higher value for brown lemmings, the most abundant species at our site. The combined daily prédation rate of avian predators exceeded the maximum daily potential growth rates of both lemming species except at the highest recorded densities for brown lemmings. We thus show, for the first time, that prédation pressure exerted without delay by avian predators can limit populations of coexisting lemming species during the snow-free period, and thus, that prédation could play a role in the cyclic dynamic of these species in the tundra. [ABSTRACT FROM AUTHOR]

In long-lived animals, survival rate is a key demographic parameter affecting population dynamics. The objective of this study was to estimate the apparent survival rate of adult Long-tailed Jaegers (Stercorarius longicaudus) breeding at one of the most northerly sites on earth, northern Ellesmere Island, Canada. Because of the large temporal fluctuations in numbers of lemmings, their primary food source during the summer, we also investigated the effect of annual variations in lemming abundance on survival rate. Analysis was based on 336 individuals marked as adults over 11 years with metal and color bands and capture-mark--recapture techniques. There was strong support for a model with two age classes, as survival of newly marked birds was 18% lower than that of previously marked ones. This difference could be due to a true age effect (if a high proportion of young adults was present in our initial samples) or, perhaps more likely, to the presence of transient individuals in the population. The estimated probability of apparent annual survival of local birds (corrected for color-band loss) was 0.91, comparable to values for other seabirds, and was constant overtime. We detected a weak trend for a decrease in apparent survival rate of newly marked birds in years of high lemming abundance but no effect on the survival of previously marked birds. This suggests that conditions at sea during the nonbreeding season may be more important in affecting annual survival. A new longevity record of 22 years was established for the species. [ABSTRACT FROM AUTHOR]

Measurements in a cylindrical Taylor-Couette device of the shear-induced radial normal stress in a suspension of neutrally buoyant non-Brownian (noncolloidal) spheres immersed in a Newtonian viscous liquid are reported. The radial normal stress of the fluid phase was obtained by measurement of the grid pressure Pg, i.e., the liquid pressure measured behind a grid which restrained the particles from crossing. The radial component of the total stress of the suspension was obtained by measurement of the pressure, Pm, behind a membrane exposed to both phases. Pressure measurements, varying linearly with the shear rate, were obtained for shear rates low enough to insure a grid pressure below a particle size dependent capillary stress. Under these experimental conditions, the membrane pressure is shown to equal the second normal stress difference, N2, of the suspension stress whereas the difference between the grid pressure and the total pressure, Pg-Pm, equals the radial normal stress of the particle phase, Σrrp. The collected data show that Σrrp is about 1 order of magnitude higher than the second normal stress difference of the suspension. The Σrrp values obtained in this manner are independent of the particle size, and their ratio to the suspension shear stress increases quadratically with [lowercase_phi_synonym], in the range 0<[lowercase_phi_synonym]<0.4. This finding, in agreement with the theoretical particle pressure prediction of Brady and Morris [J. Fluid Mech. 348, 103-139 (1997)] for small [lowercase_phi_synonym], supports the contention that the particle phase normal stress Σrrp is due to asymmetric pair interactions under dilute conditions, and may not require many-body effects. Moreover we show that the values of Σrrp, normalized by the fluid shear stress, ηf|γ| with ηf the suspending fluid viscosity and |γ| the magnitude of the shear rate, are well-described by a simple analytic expression recently proposed for the particle pressure. [ABSTRACT FROM AUTHOR]

Feet and talons are the most specialized predatory attributes of raptor morphology. As such, the hindlimb morphology of owls should reflect their dietary specialization. Owls' diet varies widely between species with only a subset of owl species preying predominantly on small mammals. We hypothesize that different owl species have varied hindlimb morphology, adapted to their main prey types, and that only dietary specialists will be distinguishable based on talon morphology (e.g. toe length, talon curvature and thickness, etc.). We used a sample of 63 specimens from 15 owl species to obtain a variety of measurements of hindlimb morphology. We then used a discriminant function analysis to investigate the degree of variation between species and diet groups in terms of their morphological measurements. Our results indicate that talon morphology is linked to prey type in the owl species studied. Insect specialists and small mammal specialists were characterized by a low talon curvature, whereas generalists presented a pronounced talon curvature. Fish specialists presented particularly thick and robust talons, and insect specialists showed lower digit strength than other owl species. These findings could help determine the diet of other owl species, particularly endangered species for which data on diet is often scarce. This study will also be very useful in future studies of the ecology of sympatric species, resource partitioning between species, or between sexes of the same species, and more generally to the evolution of owls. [ABSTRACT FROM AUTHOR]

Determining the manner in which food webs will respond to environmental changes is difficult because the relative importance of top-down vs. bottom-up forces in controlling ecosystems is still debated. This is especially true in the Arctic tundra where, despite relatively simple food webs, it is still unclear which forces dominate in this ecosystem. Our primary goal was to assess the extent to which a tundra food web was dominated by plant-herbivore or predator-prey interactions. Based on a 17-year (1993-2009) study of terrestrial wildlife on Bylot Island, Nunavut, Canada, we developed trophic mass balance models to address this question. Snow Geese were the dominant herbivores in this ecosystem, followed by two sympatric lemming species (brown and collared lemmings). Arctic foxes, weasels, and several species of birds of prey were the dominant predators. Results of our trophic models encompassing 19 functional groups showed that <10% of the annual primary production was consumed by herbivores in most years despite the presence of a large Snow Goose colony, but that 20-100% of the annual herbivore production was consumed by predators. The impact of herbivores on vegetation has also weakened over time, probably due to an increase in primary production. The impact of predators was highest on lemmings, intermediate on passerines, and lowest on geese and shorebirds but it varied with lemming abundance. Prédation of collared lemmings exceeded production in most years and may explain why this species remained at low density. In contrast, the prédation rate on brown lemmings varied with prey density and may have contributed to the high-amplitude, periodic fluctuations in the abundance of this species. Our analysis provided little evidence that herbivores are limited by primary production on Bylot Island. In contrast, we measured strong predator-prey interactions, which supports the hypothesis that this food web is primarily controlled by top-down forces. The presence of allochthonous resources subsidizing top predators and the absence of large herbivores may partly explain the predominant role of prédation in this low-productivity ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: La0.8Sr0.2CrO3 (LSC) based Ru catalysts are very active in methane steam reforming. Nevertheless, they can be easily poisoned under water-deficient conditions. Ru can be deposited as metallic ruthenium particles decorating the LSC grains or be inserted as Ru ions in the perovskite structure. Both Ru-promoted LSC catalysts were studied in methane steam reforming under water-deficient conditions and characterized after testing. Catalytic activity tests showed that ruthenium metal species are deactivated under water-deficient atmosphere, while ruthenium species inserted in LSC presented a remarkable stability and catalytic activity where residual steam plays a key role. Very unreactive carbon species responsible for deactivation were detected by temperature-programmed oxidation and transmission electron microscopy over metallic ruthenium species. Such species were not observed when ruthenium species are inserted and stabilized into the LSC structure. La0.8Sr0.2Cr0.98Ru0.02O3 appears therefore as a highly promising anti-coking anode material for Solid Oxide Fuel Cells directly fed with methane or natural gas and operating under water-deficient conditions. [Copyright &y& Elsevier]

We address the issue of segregation in bidisperse suspensions of glass beads, by using a liquid fluidized bed in the inertialess regime and an acoustic technique for acquiring the axial composition along the column. Fluidization balances the buoyancy of the particles by a constant uniform upward flow, and therefore enables long-time experiments. From the analysis of the transient segregation fronts, we have collected precise measurements on the sedimentation velocities of small and large beads, Us and Ul, in homogeneous suspensions at the same volume fraction, ¯Φ /2, for both the bead species, and for different size ratios, 1.13 ⩽ λ ⩽ 1.64, and solid concentrations, 25% ⩽ ¯Φ ⩽ 50%. Our measurements provide evidence for a difference in the sedimentation velocities, Us and Ul, over all the ranges of λ and ¯Φ covered. These results make one expect that a long-term fluidization should then result in a stationary segregated state, which was indeed always obtained for large enough particle size ratios, λ ⩾ 1.43. However, at high concentration and for particles of close sizes, λ ⩽ 1.41, we observed a surprising pseudo-periodic intermittency of slow segregation and quick mixing phases. The intermittency time is much longer than the batch sedimentation time and becomes noisy at very high concentration, for which metastable states have been observed. The origin of the mixing destabilization remains an open issue, but we note however that the domain of occurrence, λ ⩽ 1.41, also corresponds, in our experiments, to a continuous size distribution of the particles. [ABSTRACT FROM AUTHOR]

To address the issue of miscible viscous fingering instability in buoyancy free conditions, experiments have been performed under microgravity conditions in parabolic flights. A Hele-Shaw cell, two parallel plates separated by a small gap, has been used with two miscible fluids of viscosity ratio 100 (the injected fluid is the less viscous). The influence of the initial thickness of the pseudointerface between the two fluids has been studied, using flow rates large enough to prevent further mixing during displacement. The selected wavelength, measured on the observed fingering pattern, does not depend on the initial front thickness: It is around three times the gap of the cell, i.e., significantly lower than the value of five, observed on earth. However, the initial thickness does control the displacement length required for the instability to occur. Our results are in reasonable agreement with existing and new numerical simulations. [ABSTRACT FROM AUTHOR]

This study examines the relationship between personal networks and polysubstance use among people who use drugs (PWUD) in a medium sized city in the Midwest. A large body of work has demonstrated that personal relationships have an ambivalent association with substance use. On the one hand, a supportive network is associated with safer drug use practices and dramatically improves the outlook for recovery. However, individuals whose personal networks are composed of co-drug use partners are more likely to engage in risky practices. We argue that this notion of "supportive" social contacts and "risky" social contacts is ultimately incomplete: risky behaviors are introduced and further developed in a social context, often with the people who provide emotional support. We argue that personal networks with more multiplex relationships (where co-drug use and confiding fuse) are harmful because they combine norms of trust and reciprocity with drug use. We use data from the Rural Health Cohort (RHC) study to test this idea. The sample consists of 120 adult PWUD in a medium sized city located in southeastern Nebraska who were recruited using respondent-driven sampling. Participants listed up to nine confidants and nine co-drug use partners, indicating any overlap between the two networks. Our results demonstrate that multiplex ties are as strongly associated with polysubstance use as simple co-drug use relationships. As the drug crisis has increasingly shifted to underserved populations outside large urban centers, this paper represents an important advance in our understanding of the current drug crisis. [ABSTRACT FROM AUTHOR]

Blastomyces dermatitidis, the etiologic agent of blastomycosis, causes severe disease and substantial mortality in those immunocompromised by acquired immunodeficiency syndrome or malignancy. In solid organ transplant recipients, the epidemiology, clinical features, and outcomes have not been fully described. Methods. We conducted a retrospective case-series at the University of Wisconsin Hospital and Clinics. Case patients were solid organ transplant recipients with blastomycosis. Results. From 1986 to 2004, we identified 11 cases of post-transplant blastomycosis with 64% occurring between 2000 and 2004. Onset of infection occurred a median of 26 months post transplantation with near equal distribution before and after the first year of transplantation. Rejection did not precede any case of post-transplant blastomycosis. Opportunistic co-infections were common, occurring in 36% of patients. Pneumonia was the most common clinical presentation and was frequently complicated by acute respiratory distress syndrome (ARDS). Extrapulmonary disease predominantly involved the skin and spared the central nervous system. The overall mortality rate was 36%; however, this increased to 67% in those with ARDS. None of the surviving patients relapsed or received routine secondary antifungal prophylaxis. Conclusion. Blastomycosis is an uncommon infection following solid organ transplantation that is frequently complicated by ARDS, dissemination, and opportunistic co-infection. After cure, post-transplant blastomycosis may not require lifelong antifungal suppression. [ABSTRACT FROM AUTHOR]

Aims: To develop a DNA microarray for easy and fast detection of trichothecene- and moniliformin-producing Fusarium species. Method and Results: A DNA microarray was developed for detection and identification of 14 trichothecene- and moniliformin-producing species of the fungal genus Fusarium. The array could also differentiate between four species groups. Capture probes were designed based on recent phylogenetic analyses of translation elongation factor-1 alpha (TEF-1 α) sequences. Particular emphasis was put on designing capture probes corresponding to groups or species with particular mycotoxigenic synthetic abilities. A consensus PCR amplification of a part of the TEF-1 α is followed by hybridization to the Fusarium chip and the results are visualized by a colorimetric Silverquant detection method. We validated the Fusarium chip against five naturally infected cereal samples for which we also have morphological and chemical data. The limit of detection was estimated to be less than 16 copies of genomic DNA in spiked commercial wheat flour. Conclusions: The current Fusarium chip proved to be a highly sensitive and fast microarray for detection and identification of Fusarium species. We postulate that the method also has potential for (semi-)quantification. Significance and Impact of the Study: The Fusarium chip may prove to be a very valuable tool for screening of cereal samples in the food and feed production chain, and may facilitate detection of new or introduced Fusarium spp. [ABSTRACT FROM AUTHOR]

Many precocial birds make long-distance movements with their young after hatch to reach the best foraging sites. On Bylot Island, Nunavut, a large number of Greater Snow Goose (Chen caerulescens atlantica L., 1758) families move 30 km from the main nesting colony (MNC) to reach the main brood-rearing area (MBR) soon after hatch. Geese moving from the MNC to the MBR generally rear lighter and smaller goslings than geese that avoid this movement by both nesting and rearing their brood at the MBR. In this study, we tested the hypotheses that use of low-quality habitats and an increase in the time spent walking at the expense of foraging during movements could explain the reduced growth of goslings in those families. We conducted visual observations to compare habitat use and selection as well as behaviour of geese during brood movements from the MNC to the MBR (i.e., at a transit area) with those of families that had already settled at the MBR. We also conducted aerial tracking to monitor habitat use of 16 radio-marked females during and after brood movements. Streams, wet polygons, and lakes, considered high-quality habitats in terms of feeding opportunities and predator refuges, were preferred, while upland, a low-quality habitat, was avoided at both the transit area and the MBR. However, broods were found in the upland habitat more often during movements than once settled on a rearing site. The behaviour of unmarked geese at the transit site did not differ from that of geese at the MBR. We suggest that reduced food intake in low-quality habitats during movements, but not the increase in time spent walking, may explain the reduction in growth observed at fledging in goslings moving from the MNC to the MBR. [ABSTRACT FROM AUTHOR]

(1) Spring gazing by greater snow geese causes damage to hayfields of Phleum pratense L. and Trifolium pratense L. in Québec. In the hope of reducing the use of these fields by geese, we sought alternative forage mixtures that were less palatable to geese than Phleum/trifolium. (2) Three grass species (Bromus intermis Leyss, Dactylis glomerata L., and Phalaris arundinacea L._ and two legumes (Medicago sativa L. and Lotus corniculatus L.) were tested. These species, along with Phleum and Trifolium, were combined into eight mixtures (grass/legume). We ran two series of tests, one with the pure species and one with the mixtures. (3) Preference tests were run by presenting to wild-caught captive geese a pair of trays with different species (or mixtures)during 30-min trials. (4) Among legumes, Trifolium ranked highest and Lotus lowest in preference, whereas Medicago was intermediate. Among grasses, Phalaris was the preferred species followed by Dactylis, Bromus and Phleum. (5) Species tested differed significantly in water, neutral detergent fibre, protein, and phenol content. However, preferences exhibited by geese were positively correlated with water content only. (6) When palatability alone is considered, the substitution of Lotus or Medicago to Trifolium could reduce the attractiveness of hayfields to snow geese. [ABSTRACT FROM AUTHOR]

(1) The faecal output of geese (Anseriformes) is often measured in the course of bioenergeic or flock management studies. The first objective of this investigation was to examine the influence of method on the field assessment of defaecation rate in greater snow geese (Chen caerulescens atlantica (Linnaeus)). (2) We introduce the 'hourly block method', the only one which produced unbiased estimates of this parameter: 'direct interval estimate' and 'short-cut' methods (in particular Owen's half-time interval) were found to produce biased and/or high variance estimates and were deemed unreliable in most circumstances. Computer modeling confirmed these conclusions. (3) The second objective of the investigation was to identify the sources of bias and variance affecting dropping-count estimates obtained in sample plots. (4) The observation method chosen (observer standing or crouched, observer single or paired) had a great effect on the size of the bias encountered. Variance due to observer, plot and habitat was also assessed. (5) Suggestions to stabilize and/or remove causes of bias and to improve the precision of dropping-count estimates are given. [ABSTRACT FROM AUTHOR]

Examines the flow patterns of suspended anisotropic reflective particles. Motion of triaxial ellipsoids; Discussion on the asymptomatic trajectory and transient time; Laser sheet visualization of classical three-dimensional flows; Quantitative comparison between computational fluid dynamics and experimental visualizations.

To assess real-world treatment patterns and HRU among US mRCC patients from the HealthCore Integrated Research Database. Although duration of 1L was similar in IO and TKI cohorts, patients in IO cohort had lower utilization of select HRU. [Extracted from the article]

Microincision vitrectomy surgery (MIVS) and small-gauge instrumentation have improved vitrectomy procedures and increased their application in a range of vitreoretinal conditions. The objective of this systematic literature review was to identify publications reporting the efficacy and safety of MIVS tools in vitreoretinal diseases in clinical and real-world settings. [Extracted from the article]

Background: Ecological momentary assessment (EMA) is an increasingly popular and feasible form of data collection, but it can be intensive and intrusive. Especially for at-risk, vulnerable populations like people who use drugs (PWUD), poor experiences with EMA may exacerbate existing chronic struggles while decreasing response rates. However, little research queries participants' experiences with EMA studies. Objectives: We explore participants' positive and negative experiences with EMA, identifying what they liked about the study, the problems they experienced, and suggested solutions to these problems. Methods: Results come from semi-structured interviews from 26 PWUD (6 women; 20 men) in Nebraska who participated in a two-week EMA pilot study on drug use with a study-provided smartphone. Participant responses were recorded by interviewers into open-text fields in Qualtrics. Data were analyzed with an iterative open coding procedure. Results: We found that many participants enjoyed the study and seamlessly incorporated the phone into their daily lives. There were a number of negative study aspects identified, however, as many participants experienced functional issues (e.g., running out of high-speed data, trouble keeping the phone charged, not able to answer questions within the two-hour timeframe) that detracted from their experience, especially if they were homeless. Conclusion: Our findings provide methodological considerations for studies with EMA components among at-risk, vulnerable populations, like PWUD. These suggestions are targeted toward the continued ethical collection of high-quality data in clinical and non-clinical settings. [ABSTRACT FROM AUTHOR]

Network-based intervention strategies can be effective and cost-efficient approaches to curtailing harmful contagions in myriad settings. As studied, these strategies are often impractical to implement, as they typically assume complete knowledge of the network structure, which is unusual in practice. In this paper, we investigate how different immunization strategies perform under realistic conditions—where the strategies are informed by partially-observed network data. Our results suggest that global immunization strategies, like degree immunization, are optimal in most cases; the exception is at very high levels of missing data, where stochastic strategies, like acquaintance immunization, begin to outstrip them in minimizing outbreaks. Stochastic strategies are more robust in some cases due to the different ways in which they can be affected by missing data. In fact, one of our proposed variants of acquaintance immunization leverages a logistically-realistic ongoing survey-intervention process as a form of targeted data-recovery to improve with increasing levels of missing data. These results support the effectiveness of targeted immunization as a general practice. They also highlight the risks of considering networks as idealized mathematical objects: overestimating the accuracy of network data and foregoing the rewards of additional inquiry. Author summary: It is often useful to track how epidemics spread through populations by mapping transmissions between people, communities, and cities. This consideration of a population as a network can reveal the critical players, locations, or events driving epidemics. Similarly, by mapping the network of possible transmissions before an outbreak occurs, we can identify potentially critical actors on which public health interventions should focus. Unfortunately, the data collection process required to map all possible interactions of a population is difficult— fraught with possible error and unlikely to be complete. To understand the role of data quality in network-based interventions, we apply different strategies to partially-observed networks with controllable amounts of missing data. Our results suggest that intervention strategies which require full network information remain fairly effective up to high levels of missing data. However, local strategies which rely only on small data samples can outperform the more data-expensive benchmark strategies when little data is available. Surprisingly, we also propose an intervention that improves in effectiveness with less data by coupling targeted immunization with targeted data recovery. These results show that insights from network science can be robust to missing data, but that their implementation should be adjusted for noisy real-world applications. [ABSTRACT FROM AUTHOR]

Background: Trastuzumab-or lapatinib-based therapies are recommended by the National Comprehensive Cancer Network (NCCN) guidelines as preferred agents for metastatic HER2-positive breast cancer. Few studies have compared treatment patterns, healthcare resource utilization (HRU), and costs in metastatic breast cancer (MBC) patients receiving trastuzumab vs. lapatinib. The objective of this study was to compare discontinuation rates, HRU, and costs in MBC patients (pts) initiated on trastuzumab vs. lapatinib. Methods: MBC adult women initiated on trastuzumab or lapatinib on/after 03/13/2007 (lapatinib FDA-approval date) were selected from the US-based PharMetrics® Integrated Database (2000-2011). Selected pts were required to be continuously eligible in their healthcare plan ≥ 6 months prior to and ≥ 30 days following trastuzumab or lapatinib initiation date. Pts were observed over the period spanning from trastuzumab or lapatinib initiation date (without restriction on line of therapy) up to the end of continuous health plan enrollment or data availability, whichever occurred first. Trastuzumab or lapatinib discontinuation rates (gap ≥ 45 consecutive days) were compared using multivariate Cox proportional-hazards models and reported as hazard ratios (HRs). Incremental HRU was estimated using negative binomial regression models and reported as incidence rate ratios (IRRs). Monthly cost difference (2010 USD; measured from a payer perspective) were estimated using multivariate generalized linear or two-part models. Since a large proportion of lapatinib users were previously treated with trastuzumab, a sensitivity analysis was conducted to control for the impact of prior trastuzumab use. Results: Among the 643 pts selected, 381 and 262 pts were initiated on trastuzumab and lapatinib, respectively. Of the 262 pts initiated on lapatinib, 171 (65%) were previously treated with trastuzumab. After adjustment for confounders (demographics, index year, prior MBC therapies, comorbidities, baseline HRU, and MBC duration), compared to trastuzumab users, lapatinib users had a higher rate of treatment discontinuation (HR = 1.57; p < .001). While lapatinib users had a higher rate of outpatient visits (not treatment administration related) compared to trastuzumab users (HR = 1.19; p < 0.004), there were no observed significant differences of other HRU and total monthly healthcare costs between the two groups ($11,138±8,751 vs. $11,159 ±8,674, respectively; adjusted difference=$637 p = .397). Sensitivity analyses showed that pts who were initiated on lapatinib without prior trastuzumab use had a higher incidence of inpatient admissions (IRR = 1.74; p = .002) and greater overall medical service costs compared to pts who were initiated on trastuzumab (adjusted difference=$3,059; p < .001). Conclusion: Overall, while MBC pts initiated on trastuzumab or lapatinib had similar healthcare costs, pts initiated on lapatinib had higher rates of treatment discontinuation and outpatient visits (not treatment administration related). Medical costs were significantly higher among pts initiated on lapatinib without prior trastuzumab use. [ABSTRACT FROM AUTHOR]

We report experimental results on the stability of the flow occurring in a curved rectangular duct of small aspect ratio, where the centrifugational forces act along the largest dimension. The basic flow is three-dimensional as in a square or circular curved duct, and above a critical flow rate, streamwise vortices are observed. The threshold of the instability is found to be controlled by a Dean number. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The importance of community relocation experiences for aboriginal land claims movements is well documented; the role played by successful land claims in prompting ongoing out-migration is not. Data collected in 2011 on the lives of migrants are used to test three hypotheses: H1, Inuit leaving the land claims area for a nearby nonaboriginal city show markedly different social outcomes based on the length of time since migration; H2, these social outcomes map onto patterns of intergroup boundaries in their new communities; and H3, both of these outcomes are better explained by migration patterns after the land claims than by the ethnic/racial exclusion that has been the focus of past research on inequality in the region. This analysis takes advantage of social network techniques used to study hard-to-reach populations, showing how these methods can be used to address broader questions of community structure and cohesion during rapid social change. Conclusions focus on the experiences of migrants on the margins of sending and receiving communities and what they can tell us about the role played by aboriginal land claims in the culture politics of industrial resource extraction. [ABSTRACT FROM AUTHOR]

Irruptive migration is mostly observed in species specialized on pulsed resources and is thought to be a response to unpredictable changes in food supply. We assessed two alternative hypotheses to explain the periodic winter irruptions of snowy owls Bubo scandiacus every 3-5 years in temperate North America: (a) the lack-of-food hypothesis, which states that a crash in small mammal abundance on the Arctic breeding grounds forces owls to move out of the tundra massively to search for food in winter; (b) the breeding-success hypothesis, which states that high abundance of tundra small mammals during the summer allows for high production of young, thus increasing the pool of migrants moving south the following winter. We modeled winter irruptions of snowy owls in relation to summer food resources and geographic location. Winter abundance of owls was obtained from citizen-based surveys from 1994 to 2011 and summer abundance of small mammals was collected in summer at two distant sites in Canada: Bylot Island, NU (eastern High Arctic) and Daring Lake, NWT (central Low Arctic). Winter owl abundance was positively related to prey abundance during the previous summer at both sites and tended to decrease from western to eastern temperate North America. Irruptive migration of snowy owls was therefore best explained by the breeding success hypothesis and was apparently caused by large-scale summer variations in food. Our results, combined with previous findings, suggest that the main determinants of irruptive migration may be species specific even in a guild of apparently similar species. [ABSTRACT FROM AUTHOR]

Objective: Our primary objective was to evaluate how the Indigenous Healing and Seeking Safety (IHSS) model impacted residential addiction treatment program completion rates. Our secondary objective was to evaluate health service use 6 months before and 6 months after residential treatment for clients who attended the program before and after implementing IHSS.Methods: We observed clients of the Benbowopka Residential Treatment before IHSS implementation (from April 2013 to March 31, 2016) and after IHSS implementation (from January 1, 2018 - March 31, 2020). The program data were linked to health administration data, including the Ontario Health Insurance Plan (OHIP) physician billing, the Registered Persons Database (RPDB), the National Ambulatory Care Reporting System (NACRS), and the Discharge Abstract Database (DAD). Chi-square tests were used to compare patient characteristics in the no-IHSS and IHSS groups. We used logistic regression to estimate the association between IHSS and treatment completion. We used generalized estimating equation (GEE) regression model to evaluate health service use (including primary care visits, ED visits overall and for substance use, hospitalizations and mental health visits), Results: There were 266 patients in the no-IHSS group and 136 in the IHSS group. After adjusting for individual characteristics, we observed that IHSS was associated with increased program completion rates (odds ratio = 1.95, 95% CI 1.02-3.70). There was no significant association between IHSS patients' health service use at time one or time two. Primary care visits time 1: aOR 0.55, 95%CI 0.72-1.13, time 2: aOR 1.13, 95%CI 0.79-1.23; ED visits overall time 1: aOR 0.91, 95%CI 0.67-1.23, time 2: aOR 1.06, 95%CI 0.75-1.50; ED visits for substance use time 1: aOR 0.81, 95%CI 0.47-1.39, time 2: aOR 0.79, 95%CI 0.37-1.54; Hospitalizations time 1: aOR 0.78, 95%CI 0.41-1.47, time 2: aOR 0.76, 95%CI 0.32-1.80; Mental health visits time 1: aOR 0.66, 95%CI 0.46-0.96, time 2: aOR 0.92 95%CI 0.7-1.40.Conclusions: Our results indicate that IHSS positively influenced program completion but had no significant effect on health service use.Trial Registration: This study was registered with clinicaltrials.gov (identifier number NCT04604574). First registration 10/27/2020. [ABSTRACT FROM AUTHOR]

Basalt columns, septarias, and mud cracks possess beautiful and intriguing crack patterns that are hard to predict because of the presence of cracks intersections and branches. The variational approach to brittle fracture provides a mathematically sound model based on minimization of the sum of bulk and fracture energies. It does not require any a priori assumption on fracture patterns and can therefore deal naturally with complex geometries. Here, we consider shrinkage cracks obtained during unidirectional drying of a colloidal suspension confined in a capillary tube. We focus on a portion of the tube where the cross-sectional shape cracks does not change as they propagate. We apply the variational approach to fracture to a tube cross-section and look for two-dimensional crack configurations minimizing the energy for a given loading level. We achieve qualitative and quantitative agreement between experiments and numerical simulations using a regularized energy (without any assumption on the cracks shape) or solutions obtained with traditional techniques (fixing the overall crack shape a priori). The results prove the efficiency of the variational approach when dealing with crack intersections and its ability to predict complex crack morphologies without any a priori assumption on their shape. [ABSTRACT FROM AUTHOR]

Abstract: Three perovskites with the general formula La0.75Ba x Sr0.25−x Cr0.5Mn0.5O3 (x = 0, 0.10 and 0.25) have been synthesized. For all materials, the symmetry is rhombohedral (space group R-3c). On the electrical point of view, a p-type semiconducting behaviour was evidenced in the series. The addition of barium yields an increase in total conductivity in argon from 18 S cm−1 for La0.75Sr0.25Cr0.5Mn0.5O3 to 26 S cm−1 for La0.75Ba0.25Cr0.5Mn0.5O3 at 900 °C. However, in H2–3% H2O, the total conductivity decreases for all compositions and it decreases with barium substitution (0.9 S cm−1 for La0.75Sr0.25Cr0.5Mn0.5O3 and 0.5 S cm−1 for La0.75Ba0.25Cr0.5Mn0.5O3 at 900 °C). Steady state and impedance spectroscopy measurements were performed on dense pin-shaped electrodes (x = 0 and 0.25) in H2–3% H2O between 800 and 900 °C. For x = 0.25, electrochemical performances are interesting for an applicability as an SOFC anode. Origins of individual contributions to the electrode reaction mechanism are discussed. [Copyright &y& Elsevier]

Abstract: In the search for new air electrode materials for Proton Conducting Cells (PCC), the case of basic (rare earth and/or alkaline earth containing) oxocobaltites has been considered to find materials exhibiting mixed electron and proton conductivity. The stability in dry and wet air of classical (cubic and derived) as well as hexagonal 2H perovskite structures has been examined. The following compositions were studied: LaCoO3, Sr0.5La0.5CoO3, SrCoO3, Ba0.5Sr0.5CoO3, BaCoO3 and Ba0.5La0.5CoO3. Among them, four materials appeared to be stable enough in the selected operating conditions of ageing: BaCoO3, LaCoO3, Sr0.5La0.5CoO3 and Ba0.5La0.5CoO3. The reactivity study of the latter materials with the classical BaZr0.9Y0.1O3 electrolyte material has also been studied. Oxygen vacancy formation and structural water incorporation was analyzed by iodometry and TGA allows identifying them as the best compromise of the series for a PCC air electrode application. [Copyright &y& Elsevier]

Analysis of carbon (13C/12C) and nitrogen (15N/14N) stable isotope ratios (hereafter δ13C and δ15N, respectively) in animal tissues is a powerful tool in food-web studies. However, isotopic ratios of prey are not transmitted directly to a consumer, as a diet-tissue discrimination factor (denoted Δ) occurs between sources and consumer's tissues. An accurate assessment of the diet of a consumer with stable isotopes thus requires that the Δ13C and Δ15N of the studied species are known. Our aim was to establish Δ13C and Δ15N values in the Snowy Owl ( (L., 1758)). Moreover, we assessed the potential effect of ethanol preservation of blood samples on δ13C and δ15N values. We kept four captive adult Snowy Owls on a pure diet of mice for ≥6 weeks. We then collected mouse muscle and blood samples from the owls and analyzed their δ13C and δ15N values. Δ13C and Δ15N values (mean ± SE) for owl blood were +0.3‰ ± 0.2‰ and +1.9‰ ± 0.1‰, respectively. These values are the first discrimination factors ever reported in Strigiformes and are lower, for Δ15N, than those obtained in terrestrial carnivores and other bird species, including falcons. Preservation in ethanol did not significantly affect δ13C and δ15N values. [ABSTRACT FROM AUTHOR]

Capture-recapture (CR) models assume marked individuals remain at risk of capture, which may not be true if individuals lose their mark or emigrate definitively from the study area. Using a double-marking protocol, with a main and auxiliary mark, and both live encounters and dead recoveries at a large scale, partially frees CR models from this assumption. However, the auxiliary mark may fall off and its presence is often not mentioned when dead individuals are reported. We propose a new model to deal with heterogeneity of detection and uncertainty of the presence of an auxiliary mark in a multi-event framework. Our general model, based on a double-marking protocol, uses information from physical captures/recaptures, distant observations and main mark recoveries from dead animals. We applied our model to a 13-year data set of a harvested species, the Greater Snow Goose. We obtained seasonal survival estimates for adults of both sexes. Survival estimates differed between models where the presence of the auxiliary mark upon recovery was ignored versus those where the presence was accounted for. In the multi-event framework, seasonal survival estimates are no longer biased because the heterogeneity due to the presence of an auxiliary mark is accounted for in the estimation of recovery rates. Note: An illustration of the implementation of our model in E-SURGE is available online. [ABSTRACT FROM AUTHOR]

Abstract: Emissions and efficiency of a pellet boiler (40 kW) at nominal load were compared with emissions and efficiency at reduced load, while fired with six biomass pellets. The pellets include reed canary grass (Phalaris arundinacea), pectin waste from citrus shells (Citrus reticulata), sunflower husk (Helianthus annuus), peat, wheat straw (Triticum aestivum) and wood pellets. The measurements of emissions comprised of carbon monoxide (CO), nitrogen oxides (NO x ), sulphur oxides (SO x ) and flue dust mass concentrations (using DINplus and isokinetic sampling techniques). Emissions varied as a function of operational loads, for each type of pellets. The CO emissions were insignificant with reed canary grass (RCG), citrus pectin waste (CPW) and straw pellets at nominal load, however, at reduced load same pellets emitted 1.9, 4.0 and 7.4 times higher CO than wood pellets, respectively. Peat pellets emitted maximum CO at nominal load (4221.1 mgNm−3, 12.6 times higher than wood pellets) however; at reduced load CO emission was insignificant. The highest NO x emissions were reported with CPW, which were 3.4 and 4.6 times higher than wood pellets at nominal load and reduced load, respectively. Dust emissions were highest with sunflower husk and lowest with RCG pellets, at both operational modes. The best performance was reported with wood pellets, followed by RCG and pectin pellets, however, wood pellets combustion emitted 1.7 and 2.0 times higher dustDINplus than RCG at nominal and reduced loads, respectively. Not only fuel specific combustion optimization but also operational load specific optimization is essential for efficient use of agro-pellets in this type of boilers. [ABSTRACT FROM AUTHOR]

Abstract: Emissions from a multi-fuel domestic boiler (40 kW), fired with nine different agro-biomass pellets have been compared. The pellets include apple pomace (Malus domestica), reed canary grass (Phalaris arundinacea), pectin waste from citrus shells (Citrus reticulata), sunflower husk (Helianthus annuus), peat, two types of straw pellets and two types of wood pellets. The measurements of emissions comprised carbon monoxide (CO), nitrogen oxides (NOx), unburned hydrocarbons (CxHy), sulphur oxides (SOx) and flue dust mass concentration (by DINplus and isokinetic sampling methods). Comparison of experimental emission values with relevant quality labels (Blue Angel and Swan Mark) and standard (EN-303-5) showed that the boiler satisfied the emissions requirements of Blue Angel, Swan Mark and EN-303-5 when using wood pellets-1 (except CO emission), reed canary grass and citrus pectin waste pellets as fuel at nominal load. The wood pellets-1 yielded the highest boiler efficiency of 92.4%. Dusts emission varied as a function of fine content and elemental constituent of the pellets and was the highest with sunflower husk. CO and CxHy emissions were maximum with peat pellets. NOx emissions were below the concerned permissible values with all experimental pellets. Emissions of NOx and SOx were found maximum with straw pellets. For agro-pellets, statistical differences in ash contents were significant. High ash contents and low ash melting temperature made straw pellets less suitable for domestic applications. Reed canary grass, citrus pectin and apple pellets were the most suitable agro-pellets for small scale boilers with reasonable less ash contents and less emissions as compared to others. [ABSTRACT FROM AUTHOR]

Food-caching by arctic foxes (Vulpes lagopus (L., 1758)) is a behavioural adaptation thought to increase winter survival, especially in bird colonies where a large number of eggs can be cached during a short nesting season. In this paper, we measured the energy content of greater snow goose (Chen caerulescens atlantica Kennard, 1927) eggs and evaluated their perishability when cached in tundra soil for a whole summer. We estimated that eggs lost only ~8% of their dry mass over 60 days of storage in the ground. We used published estimates on digestibility of nutrients by arctic foxes to estimate that fresh and stored goose eggs contained 816 and 730 kJ of metabolizable energy, respectively, a difference of 11%. Using information on arctic fox energetics, we evaluated that 145 stored eggs were required to sustain the growth of one pup from the age of 1 to 3 months (nutritional independence). Moreover, 23 stored eggs were energetically equivalent to the average fat deposit of an arctic fox during winter. Finally, we calculated that an adult arctic fox would need to recover 160-220 stored eggs to survive 6 months in resting conditions during cold winter temperatures. This value increased to 480 when considering activity cost. Based on egg acquisition and caching rates observed in many goose colonies, we conclude that cached eggs represent an important source of energy relative to the needs of an arctic fox during winter, and have thus a high fitness value. [ABSTRACT FROM AUTHOR]

This study examines the static position sense from the ankle joint following a unilateral exhaustive stretch-shortening cycle (SSC)-type exercise involving mostly the triceps surae muscle group. Fatigue effects were quantified within the exercised and non-exercised leg through a maximal isometric voluntary plantarflexion test (MVC) performed immediately before (Pre) and after the SSC exercise, and repeated 2 (D2) and 8 (D8) days later. The static position sense test consisted in active reproductions with the non-exercised ankle of two target dorsiflexed positions (small and large) previously maintained with either the non-exercised ( control procedure) or the exercised ankle ( fatigue procedure). This test was carried out at Pre, D2, and D8. At D2, the MVC test revealed significant decreases in voluntary soleus muscle activity and peak plantarflexion force. The position sense test showed no error in reproduction accuracy in the control procedure. In contrast, the fatigue procedure revealed an overestimation of the large dorsiflexed position, only, with an associated increase of the agonist tibialis muscle activity. In agreement with the antagonist (stretched) muscle influence on the position sense, this overestimation is mostly attributed to potential SSC fatigue effects on ascending proprioceptive afferents issued from the exercised/inflamed antagonist muscles. [ABSTRACT FROM AUTHOR]

Previous studies have shown that the perception of the earth-based visual horizon, also named Gravity Referenced Eye Level (GREL), is modified by body tilt around a trans-ocular axis. Here, we investigated whether estimates of the elevation of a luminous horizontal line presented on a screen in otherwise darkness and estimates of the possibility of passing under are identically related to body tilt in absence of motion. Results showed that subjects overestimated the elevation of the projected line, whatever their body orientation. In the same way, subjects also overestimated their capacity of passing under the line. Both estimates appeared as a linear function of body tilt, that is, forward body tilt yielded increased overestimations, and backward body tilt yielded decreased overestimations. More strikingly, the linear effect of body tilt upon these estimates is comparable to that previously observed for direct GREL judgements. Overall, these data strongly suggest that the perception of the elevation of a visible obstacle and the perception of the ability of passing under in otherwise darkness shared common processes which are intimately linked to the GREL perception. The effect of body tilt upon these perceptions may illustrate an egocentric influence upon the semi-geocentric frame of reference required to perform the task. Possible interactions between egocentric and geocentric frames of reference are discussed. [ABSTRACT FROM AUTHOR]

Background: Indigenous communities in Canada face significant challenges with intergenerational trauma, which manifests in substance use disorders. There is consensus that connecting treatment approaches to culture, land, community, and spiritual practices is a pathway to healing trauma and substance use disorders for Indigenous peoples. Indigenous residential addiction treatment programs have been established as the primary intervention to provide healing for Indigenous peoples with substance use disorders and intergenerational trauma. However, there is limited evidence demonstrating the effectiveness of these programs. In collaboration with the Benbowopka Treatment Centre, this paper describes a study protocol which aims to evaluate the effectiveness of blending Indigenous Healing Practices and Seeking Safety for the treatment of Indigenous patients with intergenerational trauma and substance use disorders. Methods: We will conduct a pre/post Quasi Experimental Community trial, to compare historical treatment outcomes for patients following the implementation of Indigenous Healing and Seeking Safety. We will conduct quantitative and qualitative analyses to understand the differences before and after the intervention is implemented. The pre- Indigenous Healing and Seeking Safety intervention study window will span from 2013 to 2016; n = 343, and the post-Indigenous Healing and Seeking Safety intervention study window from 2018 to 2020; n > 300. All participants will be enrolled in the Benbowopka residential treatment for the first time during the study periods. All data will be anonymized at the time of data entry. Propensity matching will be undertaken for patient characteristics, including sex/gender, age, and substance use type. Results and conclusions: The study findings could be used to inform intergenerational trauma and substance use disorders residential treatment programming for Indigenous communities across Canada. Our work will contribute to the field of community-based intergenerational trauma and substance use disorders programming by addressing objectives that consider: (a) the patient perspective, (b) the program perspective, and (c) the community perspective. The study findings may validate an innovative approach for evaluating the effectiveness of residential addiction treatment and particularly the effective and appropriate care for Indigenous patients with intergenerational trauma and substance use disorders. [ABSTRACT FROM AUTHOR]