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We revisit the reliance of Canada on the US for its imports using new product-level data on the country of origin, the last exporting country, and the transport mode of Canadian imports. We not only show that the US is a key supplier of Canada, but also a key logistical hub: half of the imports from non-US suppliers enter Canada through the US. Therefore, 77 percent of Canadian imports are tied to the US through production or logistical linkages, well above the 55 percent usually reported in the public debate. We show that this reliance on the US is pervasive across most product categories and for Canada’s main trade partners. We exploit this new measure of reliance on the US together with input-output tables to quantify the direct and indirect reliance of Canadian industries on the US through their input usage. For the average Canadian industry, the US-related content of its inputs reaches 24 percent. We finally discuss some of the policy implications of these results.

This paper studies how frictions in the acquisition of new customers distort the allocation of activities across heterogeneous producers. We add bilateral search frictions in a Ricardian model of trade and use French firm-to-firm trade data to estimate search frictions faced by French exporters in foreign markets. Estimated coefficients display a strong degree of heterogeneity across countries and products that correlates with various proxies for information frictions. Markets with high estimated frictions are shown to display less dispersion in sales between high- and low-productivity firms, a consequence of the distortive impact of frictions. A counterfactual reduction in the level of search frictions significantly improves the efficiency of the selection process by pushing the least productive exporters out of the market while increasing export sales at the top of the productivity distribution.

Little is known about where hotspots of gentrification emerge within a city, and the role that some types of businesses play in the process. We develop a method to detect the sectors whose presence heralds the process of gentrification in a neighborhood. We show that these sectors, mostly found in cultural and creative industries, help to anticipate neighborhood change and that their predictive power complements that of traditional gentrification determinants. We also examine mechanisms related to amenities, worker characteristics, and signaling, which are consistent with these results. The analysis illustrates the importance of businesses in the socio-demographic dynamics of neighborhoods.

Background Perioperative hypersensitivity reactions may be difficult to diagnose during general anesthesia. Postinduction hypotension is the most common sign but is not specific. It was recently suggested that low end-tidal carbon dioxide (ETco2) might be a marker of anaphylaxis (Ring and Messmer grades III to IV immediate hypersensitivity reactions) in hypotensive patients under mechanical ventilation. To test this hypothesis, the authors compared ETco2 in patients with a diagnosis of anaphylaxis and in patients with severe hypotension from any other cause after the induction of anesthesia. Methods This was a retrospective single-center case-control study in which two groups were formed from an anesthesia data warehouse. The anaphylaxis group was formed on the basis of tryptase/histamine assay data and allergy workup data recorded over the period 2010 to 2018. The control (hypotension) group consisted of all patients having experienced severe hypotension (mean arterial pressure less than 50 mmHg for 5 min or longer) with a cause other than anaphylaxis after anesthesia induction in 2017. Results The anaphylaxis and hypotension groups comprised 49 patients (grade III: n = 38; grade IV: n = 11) and 555 patients, respectively. The minimum ETco2 value was significantly lower in the anaphylaxis group (median [interquartile range]: 17 [12 to 23] mmHg) than in the hypotension group (32 [29 to 34] mmHg; P < 0.001). The area under the receiver operating characteristic curve (95% CI) for ETco2 was 0.95 (0.91 to 0.99). The sensitivity and specificity (95% CI) for the optimal cutoff value were 0.92 (0.82 to 0.98) and 0.94 (0.92 to 0.99), respectively. In multivariable analysis, minimum ETco2 was associated with anaphylaxis after adjusting for confounders and competing predictors, including arterial pressure, heart rate, and peak airway pressure (odds ratio [95% CI] for ETco2: 0.51 [0.38 to 0.68]; P < 0.001). Conclusions In case of severe hypotension after anesthesia induction, a low ETco2 contributes to the diagnosis of anaphylaxis, in addition to the classical signs of perioperative immediate hypersensitivity. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

Any average pattern observed at the population level (cross-sectional analysis) may confound two different types of processes: some processes that occur among individuals and others that occur within individuals. Separating within- from among-individual processes is critical for our understanding of ecological and evolutionary dynamics. The within-individual centring method allows distinguishing within- from among-individual processes and this method has been widely used in ecology to investigate both linear and quadratic patterns. Here we show that two alternative equations could be used for the investigation of quadratic within-individual patterns. We explain the different assumptions and constraints of both equations. Reviewing the literature, we found that mainly one of these two equations has been used in studies investigating quadratic patterns. Yet this equation might not be the most appropriate in all circumstances leading to bias and imprecision. We show that these two alternative equations make different assumptions about the shape of the within-individual pattern. One equation assumes that the within-individual effect is related to an absolute process whereas the other assumes the effect arises from an individual relative process. The choice of using one equation instead of the other should depend upon the biological process investigated. Using simulations, we showed that a mismatch between the assumptions made by the equation used to analyse the data and the biological process investigated might led to flawed inference affecting output of model selection and accuracy of estimates. We stress that the equation used should be chosen carefully. We provide step by step guidelines for choosing an equation when studying quadratic pattern with the within-individual centring approach. We encourage the use of the within-individual centring method, promoting its relevant application for nonlinear relationships.

International audience; The ability of individuals and populations to adapt to a changing climate is a key determinant ofpopulation dynamics. While changes in mean behaviour are well studied, changes in trait variancehave been largely ignored, despite being assumed to be crucial for adapting to a changingenvironment. As the ability to acquire resources is essential to both reproduction and survival,changes in behaviours that maximise resource acquisition, should be under selection. Here, usingforaging trip duration data collected over 7 years on black-browed albatrosses (Thalassarchemelanophris) on the Kerguelen Islands in the southern Indian Ocean, we examine the importanceof changes in the mean and variance in foraging behaviour, and the associated effects on fitness, inresponse to the El Niño Southern Oscillation. Using double hierarchical models, we find noevidence that individuals change their mean foraging trip duration in response to a changingenvironment, but strong evidence of changes in variance. Younger birds showed greater variabilityin foraging trip duration in poor conditions as did birds with higher fitness. However, duringbrooding, birds showed greater variability in foraging behaviour under good conditions,suggesting that optimal conditions allow the alteration between chick provisioning and selfmaintenancetrips. We found weak correlations between sea-surface temperature and the El NiñoSouthern Oscillation, but stronger links with sea-level pressure. We suggest that variability inbehavioural traits affecting resource acquisition is under selection and offers a mechanism bywhich individuals can adapt to a changing climate. Studies which look only at effects on meanbehaviour may underestimate the effects of climate change and fail to consider variance in traits asa key evolutionary force.

Body mass is often viewed as a proxy of past access to resources and of future survival and reproductive success. Links between body mass and survival or reproduction are, however, likely to differ between age classes and sexes. Remarkably, this is rarely taken into account in selection analyses. Selection on body mass is likely to be the primary target accounting for juvenile survival until reproduction but may weaken after recruitment. Males and females also often differ in how they use resources for reproduction and survival. Using a long‐term study on body mass and annual survival in yellow‐bellied marmots (Marmota flaviventer), we show that body mass was under stabilizing viability selection in the first years of life, before recruitment, which changed to positive directional selection as age increased and animals matured. We found no evidence that viability selection across age classes on body mass differed between sexes. By investigating the link between running speed and body mass, we show that the capacity to escape predators was not consistent across age classes and followed a quadratic relationship at young ages only. Overall, our results indicate that mature age classes exhibit traditional patterns of positive viability selection on body mass, as expected in a hibernating mammal, but that mass in the first years of life is subjected to stabilizing selection which may come from additional predation pressures that negate the benefits of the largest body masses. Our study highlights the importance to disentangle selection pressures on traits across critical age (or life) classes., Age‐specific links between body mass and survival are rarely taken into account in selection analyses. In our study, we show how selection on body mass changes with age in a hibernating mammal, yellow‐bellied marmots (Marmota flaviventer), from stabilizing selection at young ages to directional at older. We also show that predation on young individuals may provide a mechanism by which selection acts by quantifying the relationship between maximum running speed and body mass at all ages

International audience; Within an industrial manufacturing process, tolerancing is a key player. The dimensions uncertainties management starts during the design phase, with an assessment on variability of parts not yet produced. For one assembly step, we can gain knowledge from the tolerance range required for the parts involved. In order to assess output uncertainty of this assembly in a reliable way, this paper presents an approach based on the deviation of the sum of uniform distributions. As traditional approaches based on Hoeffding inequalities do not give accurate results when the deviation considered is small, we propose an improved upper bound. We then discuss how the stack chain geometry impacts the bound definition. Finally, we show an application of the proposed approach in tolerance design of an aircraft sub-assembly. The main interest of the technique compared to existing methodologies is the management of the confidence level and the emphasis of the explicit role of the balance within the stack chain.

Global climate change is shifting many species’ phenology and has created a number of key mismatches that threaten population persistence. Phenotypically plastic individuals have the ability to adjust their behaviour in response to environmental change. While phenotypic plasticity may serve as a buffer, it is generally not known whether in case this plasticity is insufficient there is additive genetic variation in the phenological trait so that populations’ may also show an evolutionary response. We show that hibernation emergence date of yellow-bellied marmots (Marmota flaviventer), a trait that has been significantly advancing in recent years and is associated with increased spring temperature, is phenotypically plastic. Furthermore, we used the quantitative genetic ‘animal model’ to decompose variation in emergence date and show there is significant heritable variation. We infer that so far phenotypic plasticity has allowed marmots to track the environmental changes leading to earlier emergence and suggest that in the short run, marmots may be able to continue to plastically respond to environmental change and thus that this trait potentially can evolve when the plasticity no longer buffers the selection for earlier emergence.

The natal environment can have long-term fitness consequences for individuals, particularly via ‘silver spoon’ or ‘environmental matching’ effects. Invasive species could alter natal effects on native species by changing species interactions, but this potential remains unknown. Using 17 years of data on 2588 individuals across the entire US breeding range of the endangered snail kite ( Rostrhamus sociabilis ), a wetland raptor that feeds entirely on Pomacea snails, we tested for silver spoon and environmental matching effects on survival and movement and whether the invasion of a non-native snail may alter outcomes. We found support for silver spoon effects, not environmental matching, on survival that operated through body condition at fledging, explained by hydrology in the natal wetland. When non-native snails were present at the natal site, kites were in better condition, individual condition was less sensitive to hydrology, and kites fledged across a wider range of hydrologic conditions, leading to higher survival that persisted for at least 10 years. Movement between wetlands was driven by the current (adult) environment, and birds born in both invaded and uninvaded wetlands preferred to occupy invaded wetlands post-fledging. These results illustrate that species invasions may profoundly impact the role of natal environments on native species.

Ce rapport présente une recension des travaux récents sur l’incidence fiscale de l’imposition des entreprises. Après une discussion des effets théoriques d’une hausse de la taxation des entreprises sur les actionnaires, les travailleurs et les consommateurs, les études empiriques sur le sujet sont discutées suivant quatre dimensions : (i) l’incidence de l’imposition des revenus des sociétés (en ce compris les dividendes), (ii) l’incidence de la taxation de la masse salariale, (iii) l’évitement de la taxation par les choix de localisation des unités de production, (iv) l’évitement de la taxation par les choix de localisation des profits d’un point de vue comptable. L’analyse permet de tirer 9 enseignements utiles pour penser la mise en place des politiques fiscales et leurs implications.

Nowadays, intense exotic beams are needed in order to study nuclei with very short half-life. To increase the release efficiency of the fission products, all the target characteristics involved must be improved (e.g. chemical composition, dimensions, physicochemical properties such as grain size, porosity, density…). In this article, we study the impact of the target thickness. Released fractions measured from graphite and uranium carbide pellets are presented as well as Monte-Carlo simulations of the Brownian motion.

Removal sampling data are the primary source of monitoring information for many populations (e.g., invasive species, fisheries). Population dynamics, temporary emigration, and imperfect detection are common sources of variation in monitoring data and are key parameters for informing management. We developed two open robust-design removal models for simultaneously modeling population dynamics, temporary emigration, and imperfect detection: a random walk linear trend model (estimable without ancillary information), and a 2-age class informed population model (InfoPM, closely related to integrated population models) that incorporated prior information for age-structured vital rates and relative juvenile availability. We applied both models to multiyear, removal trapping time-series of a large invasive lizard (Argentine black and white tegu, Salvator merianae) in three management areas of South Florida to evaluate the effectiveness of management programs. Although estimates of the two models were similar, the InfoPMs generally returned more precise estimates, partitioned dynamics into births, deaths, net migration, and provided a decision support tool to predict population dynamics under different effort scenarios while accounting for uncertainty. Trends in tegu superpopulation abundance estimates were increasing in two management areas despite generally high removal rates. However, tegu abundance appeared to decline in the Core management area, where trapping density was the highest and immigration the lowest. Finally, comparing abundance predictions of no-removal scenarios to those estimated in each management area suggested significant population reductions due to management. These results suggest that local tegu population control via systematic trapping may be feasible with high enough trap density and limited immigration; and highlights the value of these trapping programs. We provided the first estimates of tegu abundance, capture probabilities, and population dynamics, which is critical for effective management. Furthermore, our models are applicable to a wide range of monitoring programs (e.g., carcass recovery or removal point-counts).

For many animals, group living mitigates predation risk and ensures survival. However, in yellow-bellied marmots, increased sociality is associated with lower female reproductive success, decreased female longevity and increased overwinter mortality for both males and females, which raises questions about the adaptive value of sociality in this facultatively social mammal. Here we used social network analysis to examine the relationship between sociality and summer survival, which is almost always attributable to predation. Yearling females had enhanced survival when they had stronger social relationships and were more central in their network. Adult female survival was not associated with social network traits, but females were more likely to survive the summer if they lived in larger groups. Survival of yearling and adult males was not associated with either social network trait variation or variation in group size. These findings identify a potential benefit for marmot sociality and an explanation for marmot colony social structuring.

Warming global temperatures are affecting a range of aspects of wild populations, but the exact mechanisms driving associations between temperature and phenotypic traits may be difficult to identify. Here, we use a 36-year data-set on a wild population of red deer to investigate the causes of associations between temperature and two important components of female reproduction: timing of breeding and offspring size. By separating within- versus between-individual associations with temperature for each trait, we show that within-individual phenotypic plasticity (changes within a female's lifetime) was entirely sufficient to generate the observed population-level association with temperature at key times of year. However, despite apparently adequate statistical power, we found no evidence of any variation between females in their responses (i.e. no 'IxE' interactions). Our results suggest that female deer show plasticity in reproductive traits in response to temperatures in the year leading up to calving, and that this response is consistent across individuals, implying no potential for either selection or heritability of plasticity. We estimate that the plastic response to rising temperatures explained 24% of the observed advance in mean calving date over the study period. We highlight the need for comparable analyses of other systems to determine the contribution of within-individual plasticity to population-level responses to climate change. This article is protected by copyright. All rights reserved.

In marine ecosystems, predator-prey interactions are known to structure critical processes (e.g., trophic transfer, nutrient regeneration) and have important implications for mediating community dynamics. However, the temporal and spatial scales over which these processes operate remain poorly understood mainly because the resolution provided by traditional sampling techniques is low. In particular, tides and physical forcing pose challenges due to sampling dynamics in coastal ecosystems. Examining the fine-scale temporal and spatial dynamics of predators and prey in tidally driven estuarine ecosystems requires implementing techniques that are robust to these challenges. Here, we examine data from a high-resolution multibeam imaging sonar (DIDSON) at the confluence of an intertidal and subtidal creek over six ebb-flood cycles and quantify the temporal and spatial scales of variance between the density of predators and prey. Densities of both groups were strongly and inversely related to tidal stage, irrespective of time of day. The potential for an encounter between functional groups and utilization of the estuarine intertidal-subtidal complex was mediated by the tidal stage. When the intertidal creek was flooded, both predator and prey fishes occupied the channel more than the slopes adjacent to the marsh edge. In addition, our study demonstrated fine-scale asynchronous timing in the distribution of predators and prey, with prey densities generally peaking prior to those of predators. This suggests that the scale of variation of prey occupying the intertidal creek, which is often thought to provide refuge, drives coincidental utilization by predators and mediates their interactions.

In a variety of taxa, individuals behave in consistently different ways. However, there are relatively few studies that empirically test the potential mechanisms underlying the causes and maintenance of these personality differences. Several hypotheses for the causes and maintenance of risky personality traits have been suggested but all have received mixed support. Both the pace-of-life hypothesis and state-dependent safety hypothesis propose that differences in internal state cause and maintain personality traits. Formally, the pace-of-life hypothesis states that differences in life-history traits including productivity (growth) and residual reproductive value (age) create initial differences in individual behaviour that is later maintained by positive feedback, while the state-dependent safety hypothesis suggests that body condition (mass) is responsible for causing and maintaining behavioural differences. We tested and evaluated whether either of these two hypotheses explained the causes or maintenance of variation in risk-related personality traits –defensive aggression, activity and exploration– in yellow-bellied marmots, Marmota flaviventer. We found little support overall for these hypotheses in explaining maintenance in activity or exploration. However, for defensive aggression, we found positive feedback for both mass and age.

BACKGROUND: There is little information regarding diaphragmatic dysfunction (DD) following thoracic surgery. Ultrasound allows for non-invasive repeated assessments of diaphragmatic excursion (DE) and thickening fraction (DTF) at the bedside, reflecting DD. We aimed at determining the prevalence of DD and the time-course of DE and DTF following elective thoracic surgery. Secondary endpoints included the association between DD and postoperative complications. METHODS: We led a prospective, single center, observational study in consecutive patients undergoing thoracic surgery. DE and DTF were measured by two observers blinded to each other at 3 different time-points: prior to surgery (D-1), immediately after extubation (D0) and on postoperative day 3 (D3). The changes in excursion and thickening fraction of both hemi-diaphragms over time were compared according to the side (operated or non-operated) using a two-way ANOVA. The association with postoperative complications was assessed using logistic regression.RESULTS: Fifty patients, 60% males, aged 60±15 years were included. Surgical procedures included lobectomy (n=30), wedge-resection (n=17) or pneumonectomy (n=3). DD was highly prevalent after thoracic surgery and was observed on the operated side (or both sides) in, at least, 68% of patients immediately after surgery (D0). Among those patients, 46% still had this DD on the operated side on D3. On the operated side, we observed a decrease in DE and DTF at D0 (-0.71±0.12mm, PPPPP=0.001), ICU-admission (P=0.04) according to univariate analysis and a prolonged length in hospital (OR:1.3, 95% CI [1.1-1.7], P=0.016) according to multivariate analysis.CONCLUSIONS: Diaphragmatic Dysfunction (DD) was very common after thoracic surgery, mainly concerned the operated side and was associated with an increase in the diaphragmatic excursion on the non-operated side. When this dysfunction failed to regress within 72 hours, it was associated with a significant increase in the length of hospital stay.

Imperfect detection is an important problem when counting wildlife, but new technologies such as unmanned aerial systems (UAS) can help overcome this obstacle. We used data collected by a UAS and a Bayesian closed capture-mark-recapture model to estimate abundance and distribution while accounting for imperfect detection of aggregated Florida manatees (Trichechus manatus latirostris) at thermal refuges to assess use of current and new warmwater sources in winter. Our UAS hovered for 10 min and recorded 4 K video over sites in Collier County, FL. Open-source software was used to create recapture histories for 10- and 6-min time periods. Mean estimates of probability of detection for 1-min intervals at each canal varied by survey and ranged between 0.05 and 0.92. Overall, detection probability for sites varied between 0.62 and 1.00 across surveys and length of video (6 and 10 min). Abundance varied by survey and location, and estimates indicated that distribution changed over time, with use of the novel source of warmwater increasing over time. The highest cumulative estimate occurred in the coldest winter, 2018 (N = 158, CI 141–190). Methods here reduced survey costs, increased safety and obtained rigorous abundance estimates at aggregation sites previously too difficult to monitor.

Background Diet-induced obesity can result in the development of a diverse spectrum of cardiovascular and metabolic diseases, including type 2 diabetes, dyslipidemia, non-alcoholic liver steatosis and atherosclerotic disease. MicroRNAs have been described to be important regulators of metabolism and disease development. Methods In the current study, we investigated the effects of ubiquitous miR-100 overexpression on weight gain and the metabolic phenotype in a newly generated transgenic mouse strain under normal chow and high fat diet and used microarray expression analysis to identify new potential target genes of miR-100. Results While transgenic overexpression of miR-100 did not significantly affect weight and metabolism under a normal diet, miR-100 overexpressing mice showed a reduced weight gain under a high fat diet compared to wildtype mice, despite an equal calorie intake. This was accompanied by less visceral and subcutaneous fat development and lover serum LDL cholesterol. In addition, transgenic miR-100 mice were more glucose tolerant and insulin sensitive and demonstrated increased energy expenditure under high fat diet feeding. A comprehensive gene expression profiling revealed the differential expression of several genes involved in lipid storage- and metabolism, among them CD36 and Cyp4A14. Our data showed a direct regulation of CD36 by miR-100, leading to a reduced fatty acid uptake in primary hepatocytes overexpressing miR-100 and the downregulation of several downstream mediators of lipid metabolism such as ACC1, FABP4, FAS and PPARγ in the liver. Conclusions Our findings demonstrate a protective role of miR-100 in high fat diet induced metabolic syndrome and liver steatosis, partially mediated by the direct repression of CD36 and attenuation of hepatic lipid storage, implicating miR-100 as a possible therapeutic target in liver steatosis. Supplementary Information The online version contains supplementary material available at 10.1186/s10020-021-00364-6.

Species that hibernate live longer than would be expected based solely on their body size. Hibernation is characterized by long periods of metabolic suppression (torpor) interspersed by short periods of increased metabolism (arousal). The torpor-arousal cycles occur multiple times during hibernation, and it has been suggested that processes controlling the transition between torpor and arousal states cause aging suppression. Metabolic rate is also a known correlate of longevity, we thus proposed the ‘hibernation-aging hypothesis’ whereby aging is suspended during hibernation. We tested this hypothesis in a well-studied population of yellow-bellied marmots (Marmota flaviventer), which spend 7-8 months per year hibernating. We used two approaches to estimate epigenetic age: the epigenetic clock and the epigenetic pacemaker. Variation in epigenetic age of 149 samples collected throughout the life of 73 females was modeled using generalized additive mixed models (GAMM), where season (cyclic cubic spline) and chronological age (cubic spline) were fixed effects. As expected, the GAMM using epigenetic ages calculated from the epigenetic pacemaker was better able to detect nonlinear patterns in epigenetic age change over time. We observed a logarithmic curve of epigenetic age with time, where the epigenetic age increased at a higher rate until females reached sexual maturity (2-years old). With respect to circannual patterns, the epigenetic age increased during the summer and essentially stalled during the winter. Our enrichment analysis of age-related CpG sites revealed pathways related to development and cell differentiation, while the season-related CpGs enriched pathways related to central carbon metabolism, immune system, and circadian clock. Taken together, our results are consistent with the hibernation-aging hypothesis and may explain the enhanced longevity in hibernators.

Poaching is a global problem causing the decline of species worldwide. Optimizing the efficiency of ranger patrols to deter poaching activity at the lowest possible cost is crucial for protecting species with limited resources. We applied decision analysis and spatial optimization algorithms to allocate efforts of ranger patrols throughout a national park. Our objective was to mitigate poaching activity at or below management risk targets for the lowest monetary cost. We examined this trade-off by constructing a Pareto efficiency frontier using integer linear programming. We used data from a ranger-based monitoring program in Nyungwe National Park, Rwanda. Our measure of poaching risk is based on dynamic occupancy models that account for imperfect detection of poaching activities. We found that in order to achieve a 5% reduction in poaching risk, 622 ranger patrol events (each corresponding to patrolling 1-km2 sites) were needed within a year at a cost of US$49,760. In order to attain a 60% reduction in poaching risk, 15,560 patrol events were needed at a cost of US$1,244,800. We evaluated the trade-off between patrol cost and poaching risk based on our model by constructing a Pareto efficiency frontier and park managers found the solution for a 50% risk reduction to be a practical trade-off based on funding constraints (comparable to recent years) and the diminishing returns between risk mitigation and cost. This expected reduction in risk required 8,558 patrol events per year at a cost of US$684,640. Our results suggest that optimal solutions could increase efficiency compared to the actual effort allocations from 2006 to 2016 in Nyungwe National Park (e.g., risk reductions of ~30% under recent budgets compared to ~50% reduction in risk under the optimal strategy). The modeling framework in this study took into account imperfect detection of poaching risk as well as the directional and conditional nature of ranger patrol events given the spatial adjacency relationships of neighboring sites and access points. Our analyses can help to improve the efficiency of ranger patrols, and the modeling framework can be broadly applied to other spatial conservation planning problems with conditional, multilevel, site selection.

In social species, maternal social relationships, in addition to direct care, impact offspring survival but much of what we know about these effects comes from studies of obligately social and cooperatively breeding species. Yellow-bellied marmots (Marmota flaviventer) are a facultatively social species whose social groups vary in composition, size, and cohesiveness. This natural variation in sociality and cooperative breeding behavior makes yellow-bellied marmots an ideal species within which to study the effects of maternal affiliative and agonistic social behavior on offspring. We used social network analysis to investigate the relationship between maternal social connectivity and integration on offspring summer and yearly survival, with the hypothesis that offspring with more affiliative mothers are more likely to survive than the offspring of more agonistic mothers. However, we found the inverse to be true: pups born to mothers who received more affiliative interactions were less likely to survive while the offspring of mothers who were more highly integrated into agonistic networks had enhanced survival. Overall, maternal social network measures were positively and negatively correlated with offspring survival, indicating that pups are influenced by their mother’s social world, often in contradictory ways. Relative predation risk and colony location also mediated the effects of social relationships on pup survival. This study contributes to a small but growing body of work that demonstrates that specific attributes of sociality have specific consequences and that by adopting an attribute-focused view of sociality we are better able to understand how environmental conditions mediate the costs and benefits of sociality.Lay SummaryMaternal social relationships can impact offspring survival but much of what we know about these effects comes from studies of obligately social species. In faculatively social yellow-bellied marmots we found that pups born to mothers who received more affiliative interactions were less likely to survive while the offspring of mothers who were more highly integrated into agonistic networks had enhanced survival. Overall, pups are influenced by their mother’s social world, often in contradictory ways.

Estimates of age‐specific survival probabilities are needed for age‐structured population models and to inform conservation decisions. However, determining the age of individuals in wildlife populations is often problematic. We present a hidden Markov model for estimating age‐specific survival from capture–recapture or capture–recapture–recovery data when age is unknown and indicators of age, such as size and growth layer counts, are imprecise. The model is evaluated through simulations, and its implementation is illustrated with maximum likelihood and Bayesian approaches in commonly used software. The model is then applied to genetic capture–recapture data of Florida manatees to estimate age‐ and time‐variant survival probabilities. The approach is broadly applicable to studies aiming to quantify age‐specific effects of environmental change and management actions on population dynamics, including studies that rely on minimally invasive methods such as genetic and photo identification.

Seasonal environmental conditions shape the behavior and life history of virtually all organisms. Climate change is modifying these seasonal environmental conditions, which threatens to disrupt population dynamics. It is conceivable that climatic changes may be beneficial in one season but result in detrimental conditions in another because life-history strategies vary between these time periods. We analyzed the temporal trends in seasonal survival of yellow-bellied marmots (Marmota flaviventer) and explored the environmental drivers using a 40-y dataset from the Colorado Rocky Mountains (USA). Trends in survival revealed divergent seasonal patterns, which were similar across age-classes. Marmot survival declined during winter but generally increased during summer. Interestingly, different environmental factors appeared to drive survival trends across age-classes. Winter survival was largely driven by conditions during the preceding summer and the effect of continued climate change was likely to be mainly negative, whereas the likely outcome of continued climate change on summer survival was generally positive. This study illustrates that seasonal demographic responses need disentangling to accurately forecast the impacts of climate change on animal population dynamics.

International audience; Imperfect detection and misclassification errors are often ignored in the context of invasive species management. Here we present an approach that combines spatially explicit models and an optimization technique to design optimal search and destroy strategies based on noisy monitoring observations. We focus on two invasive plants, melaleuca (Melaleuca quinquenervia) and Old World climbing fern (Lygodium microphyllum), which continue to cause important damages to the Everglades ecosystem. We present a methodological framework that combines Hidden Markov Random Field (HMRF, initially developed for image analysis) and linear programming to optimally search for invasive species. A benefit of this approach is that it accounts for the spatial structure of the system by using a spatially explicit modeling approach (i.e. HMRF), and does not require repeated visits to model the probability of occurrence of species. We found on simulated cases that our approach can lead to substantial improvements in control efficiency when compared to state of the art model-free approaches. For example, in the case of the old world fern, simulations showed that the optimal strategy would allow managers to control up to 34% more sites than with model-free approaches that ignored misclassification and imperfect detection. For melaleuca it was possible to control up to 20% more sites. The vast increase in imagery data obtained from different sources (e.g. unmanned aerial systems, and satellite) provides great opportunities to improve management of natural resources by applying modern computational methods such as the one we present. Our approach can substantially increases the efficiency of invasive species control by accounting for imperfect detection, misclassification error and the spatial structure of the system. Our approach is applicable to other systems and problems, for example it could be applied to the control of plant pathogens, or optimal extraction of resources (e.g. minerals or biological resources).

International audience; Managing spatially structured populations of imperiled species presents manychallenges. Spatial structure can make it difficult to predict populationresponses to potential recovery activities, and learning through experimenta-tion may not be advised if it could harm threatened populations. Adaptivemanagement provides an appealing framework when experimentation is con-sidered too risky or time consuming; we used such an approach for imperiledflatwoods salamanders at a Florida wildlife refuge. We represented thismetapopulation with category count models and used stochastic dynamic pro-gramming to identify optimal decision policies that weighed trade-offs betweenmetapopulation persistence and management costs. We defined possible wet-land categories in terms of habitat suitability and occupancy, specifiedcategory-specific management actions, and identified transition probabilitiesvia expert elicitation for two management strategies:“future”status quo (FSQ;frequent growing-season burns) and extra management actions (EMA; restora-tion, translocation, head-starting). We simulated metapopulation dynamicsusing the resulting optimal management policy and found that under model FSQ, occupancy steadily declined over time, indicating that populations wouldrapidly become extirpated; with model EMA, occupancy remained stable,suggesting that populations would persist only if additional actions are appliedand are effective. This approach can be used to identify optimal solutions whileaccounting for uncertainty and considering both habitat and populationdynamics, and to help managers make conservation decisions for populations at imminent risk of extinction.

International audience; Better understanding human–wildlife interactions and their links with management can help improve the design of wildlife protection zones. One example is the problem of wildlife collisions with vehicles or human-built structures (e.g., power lines, wind farms). In fact, collisions between marine wildlife and watercraft are among the major threats faced by several endangered species of marine mammals. Natural resource managers are therefore interested in finding cost-effective solutions to mitigate these threats. We combined abundance estimators with encounter rate theory to estimate relative lethal collision risk of the Florida manatee (Trichechus manatus latirostris) from watercraft. We first modelled seasonal abundance of watercraft and manatees using a Bayesian analysis of aerial survey count data. We then modelled relative lethal collision risk in space and across seasons. Finally, we applied decision analysis and Linear Integer Programming to determine the optimal design of speed zones in terms of relative risk to manatees and costs to waterway users. We used a Pareto efficient frontier approach to evaluate the performance of alternative zones, which included additional practical considerations (e.g., spatial aggregation of speed zones) in relation to the optimal zone configurations. Under the various relationships for probability of death given strike speed that we considered, the current speed zones reduced the relative lethal collision risk by an average of 51.5% to 70.0% compared to the scenario in which all speed regulations were removed (i.e., the no-protection scenario). We identified optimal zones and near-optimal zones with additional management considerations that improved upon the current zones in terms of cost or relative risk. Policy implications. Our analytical framework combines encounter rate theory and decision analysis to quantify the effectiveness of speed zones in protecting manatees while accounting for uncertainty. Our approach can be used to optimize the design of protection zones intended to reduce conflicts between human waterborne activity and marine mammals. This framework could be extended to address many other problems of human–wildlife interactions, such as the optimal placement of wind farms to minimize collisions with wildlife or the optimal allocation of ranger effort to mitigate poaching threats.

Effective conservation of endangered North Atlantic right whales Eubalaena glacialis requires information about their spatio-temporal distribution. Understanding temporal distribution is particularly important, because a portion of the population migrates between high-latitude summer feeding grounds off the northeastern USA and Canadian Maritimes coasts and lower-latitude calving and wintering grounds off the southeastern US coast (SEUS). Here, we modeled SEUS residence patterns using photo-identification data from coastal South Carolina, Georgia, and Florida from 7 winter seasons (2004/2005-2010/2011). We used multistate open robust design models to evaluate effects of reproductive status, demographic group, and environmental conditions on SEUS residence. Model estimates accounted for temporal variation and imperfect detection and provided probabilities of entering the SEUS, staying in the SEUS, and being sighted in the SEUS. We also derived estimates for residence time and seasonal abundance. We observed staggered arrival and departure patterns and demographic differences in residence patterns that are characteristic of a differential migration strategy. Calving females arrived earliest and, in most seasons, had mean residence periods more than twice as long as other demographic groups. Conversely, adult males arrived the latest and had the shortest residence times. Within-season detection was positively influenced by survey effort, and overall seasonal mean (±SE) detection rate estimates ranged from 0.83 ± 0.08 for non-calving adult females to 0.98 ± 0.02 for calving females. Results provide insights into right whale behavior, biology, and temporal distribution in the SEUS and can be used to evaluate spatially and temporally dynamic management measures.

Population projection models are important tools for conservation and management. They are often used for population status assessments, for threat analyses, and to predict the consequences of conservation actions. Although conservation decisions should be informed by science, critical decisions are often made with very little information to support decision-making. Conversely, postponing decisions until better information is available may reduce the benefit of a conservation decision. When empirical data are limited or lacking, expert elicitation can be used to supplement existing data and inform model parameter estimates. The use of rigorous techniques for expert elicitation that account for uncertainty can improve the quality of the expert elicited values and therefore the accuracy of the projection models. One recurring challenge for summarizing expert elicited values is how to aggregate them. Here, we illustrate a process for population status assessment using a combination of expert elicitation and data from the ecological literature. We discuss the importance of considering various aggregation techniques, and illustrate this process using matrix population models for the wood turtle (Glyptemys insculpta) to assist U.S. Fish and Wildlife Service decision-makers with their Species Status Assessment. We compare estimates of population growth using data from the ecological literature and four alternative aggregation techniques for the expert-elicited values. The estimate of population growth rate based on estimates from the literature (λ

Rationale: The interaction of circulating cells within the vascular wall is a critical event in chronic inflammatory processes, such as atherosclerosis, but the control of the vascular inflammatory state is still largely unclear. Objective: This study was undertaken to characterize the function of the endothelial-enriched microRNA miR-100 during vascular inflammation and atherogenesis. Methods and Results: Based on a transcriptome analysis of endothelial cells after miR-100 overexpression, we identified miR-100 as a potent suppressor of endothelial adhesion molecule expression, resulting in attenuated leukocyte–endothelial interaction in vitro and in vivo as shown by flow cytometry and intravital imaging. Mechanistically, miR-100 directly repressed several components of mammalian target of rapamycin complex 1-signaling, including mammalian target of rapamycin and raptor, which resulted in a stimulation of endothelial autophagy and attenuated nuclear factor κB signaling in vitro and in vivo. In a low-density lipoprotein receptor–deficient atherosclerotic mouse model, pharmacological inhibition of miR-100 resulted in enhanced plaque lesion formation and a higher macrophage content of the plaque, whereas a systemic miR-100 replacement therapy had protective effects and attenuated atherogenesis, resulting in a decrease of plaque area by 45%. Finally, analysis of miR-100 expression in >70 samples obtained during carotid endarterectomy revealed that local miR-100 expression was inversely correlated with inflammatory cell content in patients. Conclusions: In summary, we describe an anti-inflammatory function of miR-100 in the vascular response to injury and inflammation and identify an important novel modulator of mammalian target of rapamycin signaling and autophagy in the vascular system. Our findings of miR-100 as a potential protective anti-athero-miR suggest that the therapeutic replacement of this microRNA could be a potential strategy for the treatment of chronic inflammatory diseases, such as atherosclerosis, in the future.

At least one-third of all amphibian species face the threat of extinction, and current amphibian extinction rates are four orders of magnitude greater than background rates. Preventing extirpation often requires both ex situ (i.e., conservation breeding programs) and in situ strategies (i.e., protecting natural habitats). Flatwoods salamanders (Ambystoma bishopi and A. cingulatum) are protected under the U.S. Endangered Species Act. The two species have decreased from 476 historical locations to 63 recently extant locations (86.8% loss). We suggest that recovery efforts are needed to increase populations and prevent extinction, but uncertainty regarding optimal actions in both ex situ and in situ realms hinders recovery planning. We used structured decision making (SDM) to address key uncertainties regarding both captive breeding and habitat restoration, and we developed short-, medium-, and long-term goals to achieve recovery objectives. By promoting a transparent, logical approach, SDM has proven vital to recovery plan development for flatwoods salamanders. The SDM approach has clear advantages over other previous approaches to recovery efforts, and we suggest that it should be considered for other complex decisions regarding endangered species.

Behavior and metabolism are frontline reactions to environmental challenges that can covary in their response through at least two mechanisms. First, natural selection can generate correlation in phenotype among distinct populations if they are exposed to a common selective force. Thus, metabolism and behavior can exhibit phenotypic correlation among populations when responding (independently from each other) to co-varying selective forces. Second, because behavioral responses are energy-demanding, variation in energy acquisition or allocation among individuals of the same population can also generate, respectively, a positive or negative correlation within populations. To address this issue, we investigated among- and within-population (co)variations in exploration activity (EA) and resting metabolic rate (RMR) of adult common voles (Microtus arvalis) issued from four high-elevation populations (> 1400 m a.s.l.) and five low-elevation populations (

Between-individual variation in phenotypes within a population is the basis of evolution. However, evolutionary and behavioural ecologists have mainly focused on estimating between-individual variance in mean trait and neglected variation in within-individual variance, or predictability of a trait. In fact, an important assumption of mixed-effects models used to estimate between-individual variance in mean traits is that within-individual residual variance (predictability) is identical across individuals. Individual heterogeneity in the predictability of behaviours is a potentially important effect but rarely estimated and accounted for. We used 11 389 measures of docility behaviour from 1576 yellow-bellied marmots (Marmota flaviventris) to estimate between-individual variation in both mean docility and its predictability. We then implemented a double hierarchical animal model to decompose the variances of both mean trait and predictability into their environmental and genetic components. We found that individuals differed both in their docility and in their predictability of docility with a negative phenotypic covariance. We also found significant genetic variance for both mean docility and its predictability but no genetic covariance between the two. This analysis is one of the first to estimate the genetic basis of both mean trait and within-individual variance in a wild population. Our results indicate that equal within-individual variance should not be assumed. We demonstrate the evolutionary importance of the variation in the predictability of docility and illustrate potential bias in models ignoring variation in predictability. We conclude that the variability in the predictability of a trait should not be ignored, and present a coherent approach for its quantification.

Studies in natural populations are essential to understand the evolutionary ecology of senescence and terminal allocation. While there are an increasing number of studies investigating late-life variation in different life-history traits of wild populations, little is known about these patterns in social behaviour. We used long-term individual based data on yellow-bellied marmots (Marmota flaviventer) to quantify how affiliative social behaviours and different life-history traits vary with age and in the last year of life, and how patterns compare between the two. We found that some social behaviours and all life-history traits varied with age, whereas terminal last year of life effects were only observed in life-history traits. Our results imply that affiliative social behaviours do not act as a mechanism to adjust allocation among traits when close to death, and highlight the importance of adopting an integrative approach, studying late-life variation and senescence across multiple different traits, to allow the identification of potential trade-offs.This article is part of the theme issue ‘Ageing and sociality: why, when and how does sociality change ageing patterns?’

Self-organization is a process of establishing and reinforcing local structures through feedbacks between internal population dynamics and external factors. In reef-building systems, substrate is collectively engineered by individuals that also occupy it and compete for space. Reefs are constrained spatially by the physical environment, and by mortality, which reduces production but exposes substrate for recruits. Reef self-organization therefore depends on efficient balancing of production and occupancy of substrate. To examine this, we develop a three-dimensional individual-based model (IBM) of oyster reef mechanics. Shell substrate is grown by individuals as valves, accumulates at the reef level, and degrades following mortality. Single restoration events and subsequent dynamics are simulated for a case study in South Carolina (USA). Variability in model processes is included on recruitment, spatial environmental constraints, and predation, over multiple independent runs and five predator community scenarios. The main goal for this study is to summarize trends in dynamics that are robust across this uncertainty, and from these generate new hypotheses and predictions for future studies. Simulation results demonstrate three phases following restoration: initial transient dynamics with considerable shell loss, followed by growth and saturation of the live population, and then saturation of settlement habitat several years later. Over half of simulations recoup initial shell losses as populations grow, while others continue in decline. The balance between population density, substrate supporting the reef, and exposed surfaces for settlement is mediated by overall population size and size structure, presence of predators, and relative amounts of live individuals and intact dead shells. The efficiency of settlement substrate production improves through time as population size structure becomes more complex, and the population of dead valves accumulates.

The formation of fine particles during the Plasma Electrolytic Oxidation process (PEO) was investigated. Particles were produced by carrying out PEO treatments on two different grade of aluminium alloy (Al1050, Al2024) and a low-alloyed zirconium grade (Zr-M5). They were characterized at different scales mainly using transmission electron microscopy. Whatever the processed material, results show that particles exhibit a hollow spherical shape with outer diameter ranging from 100 nm to 10 μm. They consist of polycrystalline alumina (η- and α-Al2O3) for the PEO of aluminium alloys and zirconia (m-ZrO2) for the zirconium alloy. A correlation is drawn between the microstructure of the produced particles and the “pancake”-like structure that usually develops over PEO coatings. On this basis, a descriptive mechanism of the formation of these metal oxide particles is proposed. The ignition of a micro-discharge inside the “pancake” cavity induces the propagation of a pressure shockwave that pushes the molten oxide through the narrow orifice of the “pancake” structure. Like a rubber balloon, the molten oxide forms a hollow sphere and is rapidly quenched by the surrounding electrolyte and ejected into the electrolyte.