Search

Forecasting species' responses to climate change is critical and challenging. One commonly used approach is space-for-time substitution (SFTS), which takes the hypothesis that the biotic–climate relationships observed over space are causal, and uses this spatial relationship to predict responses over time. The underlying assumptions have seldom been tested; if not supported, the resulting predictions can be biased and have a high degree of uncertainty. We currently cannot discern for which type of species the SFTS approach is likely to be more reliable. We argue that the way forward is to test the underlying assumptions by evaluating contexts and species using a comparative approach, through improvements in the quality of biological data, and through the integration of experimental and modelling approaches to the distribution of species. To anticipate species' responses to climate change, ecologists have largely relied on the space-for-time-substitution (SFTS) approach. However, the hypothesis and its underlying assumptions have been poorly tested. Here, we detail how the efficacy of using the SFTS approach to predict future locations will depend on species' traits, the ecological context, and whether the species is declining or introduced. We argue that the SFTS approach will be least predictive in the contexts where we most need it to be: forecasting the expansion of the range of introduced species and the recovery of threatened species. We highlight how evaluating the underlying assumptions, along with improved methods, will rapidly advance our understanding of the applicability of the SFTS approach, particularly in the context of modelling the distribution of species. [ABSTRACT FROM AUTHOR]

Changes in precipitation due to climate change will have consequences for plant and herbivorous insect communities alike. Multiple hypotheses explain how changes in plant diversity and productivity can lead to changes in herbivore community composition. Yet as rainfall patterns change, the bottom‐up effects on the relationships between plant and herbivore communities are less well understood.Using a long‐term rainfall manipulation experiment in a remnant patch of Garry oak (Quercus garryana) savanna, we examined how plant diversity and productivity have responded to variation in soil moisture over 6 years. This highly endangered ecosystem is predicted to experience significantly wetter springs and drier summers by 2080. We also investigated plant‐mediated, indirect effects of manipulated rainfall on herbivore diversity and abundance, drawing on multiple hypotheses describing the relationships between plant and herbivore communities. For example, the more individuals hypothesis predicts that increased plant productivity results in increased herbivore abundance which, in turn, results in increased herbivore diversity.We found that plant productivity was influenced by soil moisture, but the direction and magnitude of the response varied across years, and found no support for plant diversity influencing productivity. We also found that the cover and productivity of grasses increased significantly with increasing precipitation. In addition to a direct negative effect on herbivore diversity, soil moisture had an indirect negative effect on herbivore abundance, via the negative effect of plant productivity on abundance, contradicting the more individuals hypothesis.Synthesis. Our results highlight that not only can drought result in significant reductions in plant productivity in this threatened ecosystem, but that these changes will also result in increases in herbivore abundance. In contrast, where soil moisture is higher, grasses will become more dominant resulting in decreased herbivore abundance. Ultimately, predicting how this system responds to changes in precipitation will depend on the ability to predict whether growing season soil moisture will be consistently drier or wetter in the future, a significant challenge. Going forward, investigating how variation in precipitation due to climate change affects the links between trophic levels, including how herbivores affect plant communities, remains critical for understanding ecosystem processes and stability. [ABSTRACT FROM AUTHOR]

Background: Ileocolic intussusception is considered a pediatric emergency, with concerns for risk of significant morbidity in children with a prolonged intussusception state. Emergent therapy is standard of care, as prior studies have shown poor outcomes in patients with long delays (> 24 h) before intervention. Various factors can result in shorter delays, and there are limited studies evaluating outcomes in these patients. This study aimed to determine if there were differences in reduction success rates associated with short in-hospital time delays.Objective: This study is to determine enema success rate and morbidity in patients with documented time delays between intussusception diagnosis and therapeutic enema.Materials and Methods: A retrospective evaluation of pediatric patients with intussusception at a single children's hospital between 2007 and 2019 was performed. Patient's records were reviewed for time of symptom onset, radiologic diagnosis, and attempted enema. Ultrasounds and radiographs were reviewed for bowel obstruction, free peritoneal fluid, trapped fluid around the intussusceptum, and absent bowel wall perfusion. Patients were evaluated for efficacy of reduction attempt, requirement for surgical reduction, and complications including bowel resection and bowel perforation.Results: There were 175 cases of ileocolic intussusception requiring enema reduction. Successful reduction occurred in 72.2% (13/18) of cases performed within 1 h of diagnosis; 74.3% (78/105) between 1 and3 h; 73.2% (30/41) between 3 and 6 h; and 81.2% (9/11) with greater than 6 h. Need for bowel resection was not associated with short delays between diagnosis and reduction attempts (p = .07).Conclusions: There was no difference in intussusception reduction efficacy or complication rate in patients with increasing time between imaging diagnosis of ileocolic intussusception and reduction attempt, including delay intervals up to 8 h. [ABSTRACT FROM AUTHOR]

Perianal Crohn's disease (CD) is a complex manifestation of CD that affects approximately 10% of patients. The spectrum of disease is quite variable, ranging from relatively mild disease to severe, aggressive manifestations that result in frequent hospitalizations, multiple surgeries, and poor quality of life. Despite significant recent advances in surgical and medical management, treatment remains challenging and frequently requires a multidisciplinary medical-surgical approach. The goal of this article is to review the current literature regarding the work-up, treatment, and future directions of therapy. Crucial features of effective management include the precise identification of manifestations, control of sepsis, limiting rectal inflammation, frequently with use of antitumor necrosis factor agents, and avoidance of extensive surgery. [ABSTRACT FROM AUTHOR]

PREMISE: Spatial variation in selective pressures can lead to intraspecific variation in life history, favoring some life histories and constraining others depending on the vulnerability of life stages. We examined how spatial variation in herbivory and climate influences flowering size and the occurrence of semelparity (reproducing once) versus iteroparity (reproducing multiple times) in the introduced range of an invasive plant, houndstongue (Cynoglossum officinale). Houndstongue is a short‐lived, semelparous perennial in its native range. In its introduced range, we previously documented increased rates of iteroparity and a higher median threshold flowering size compared to the native range. We hypothesized that the recent introduction of a specialist biocontrol insect (a root‐boring weevil, Mogulones crucifer) would decrease threshold flowering size and reduce the proportion of iteroparous plants because M. crucifer preferentially attacks large individuals and may reduce overwinter survival. METHODS: We surveyed 24 sites across the northwestern United States to quantify the frequency of semelparity versus iteroparity and to estimate weevil abundance and used demographic data collected from six sites to estimate median threshold flowering size. RESULTS: We found that sites with greater winter precipitation and no weevils had a greater proportion of iteroparous plants. Sites with higher weevil attack had a lower median threshold flowering size. CONCLUSIONS: The variation in frequency of flowering and threshold flowering size that we documented in North American houndstongue populations, and the relationships between this variation and herbivory and climate, provide evidence for how selective pressures covary with the life histories of invasive plants. [ABSTRACT FROM AUTHOR]

Eco-evolutionary theory suggests that rapid evolution can accelerate range expansion speed. In addition to average speed, recent experimental studies reveal that evolution can also influence the amount of variability across replicates of spreading populations, but in contrasting ways. Here we develop a predictive framework, drawing on ideas from population genetics and spread theory, to understand when, why, and in what direction evolution will modify the variability of range expansion. Our framework revolves around the balance of variance-generating (drift) and variance-reducing (selective) evolutionary processes, and factors that may tip this balance, including population size at the leading edge and mating system. We suggest hypotheses to clarify contrasting experimental results and highlight a way forward for studying eco-evolutionary dynamics of range expansion. Outcomes of range expansions are variable; evolution can increase or decrease that variation. Expansion outcomes reflect a balance of variance-generating and variance-reducing evolutionary processes. Mating system and edge population size may determine whether evolution increases or decreases variance. These ideas can be tested with mathematical modeling, additional experiments, and data from natural range expansions. [ABSTRACT FROM AUTHOR]

Spatial variation in abiotic and biotic factors creates local contexts that influence the intensity of plant–herbivore interactions. Some previous studies have accounted for the complexity of these interactions with latitudinal clines, while the absence of such clines in many other systems suggests other, often unknown, local community factors may instead explain the variation in herbivory across populations.We investigated plant–herbivore interactions across the entire range of a long‐lived tree (Quercus garryana), evaluating the relative importance of climate, latitude, population size, and insect feeding guilds in determining leaf phenotype and the extent and variation in insect herbivory. In this ecosystem, rain shadows create a nonlinear relationship between climate and latitude, allowing us to disentangle the effects of environmental factors. By performing similar analyses on trees grown in a common garden, we were able to assess the relative importance of environmental factors to leaf defence traits and herbivory.Total herbivory varied significantly among populations, and was best explained by variation in spring precipitation, leaf traits, and tree population size, but not latitude. The relative importance of each of these factors changed over the growing season and with insect feeding guild. Conversely, damage in the common garden did not vary among trees from different origins when grown in a constant environment, leading us to believe variation in damage in natural populations is more likely the result of the local environments.Leaf traits (trichome density and specific leaf area) varied significantly among populations, but neither showed an effect of latitude. Variation in both traits was best explained by tree size, and seasonal temperatures or precipitation. We found no variation in insect diversity among field populations, but abundance varied with mean summer precipitation and population size.Synthesis. Seasonal precipitation consistently explained the geographical variation in the extent of herbivory to Q.  garryana, while latitude and winter temperatures, factors that are commonly associated with latitudinal gradients in the intensity of species interactions, did not. Our findings highlight the importance of local climates and functional traits in shaping biotic interactions and intraspecific variation in plant–insect interactions across large spatial scales. Seasonal precipitation consistently explained the geographical variation in the extent of herbivory to Q.  garryana, while latitude and winter temperatures, factors that are commonly associated with latitudinal gradients in the intensity of species interactions, did not. Our findings highlight the importance of local climates and functional traits in shaping biotic interactions and intraspecific variation in plant–insect interactions across large spatial scales. [ABSTRACT FROM AUTHOR]

Reliable predictions of population spread rates are essential to forecast biological invasions. Recent studies have shown that populations spreading through favourable habitat can rapidly evolve higher dispersal and reproductive rates at the expansion front, which accelerates spread velocity. However, spreading populations are likely to eventually encounter stressful conditions in the expanded range. How evolution during spread in favourable environments affects subsequent population growth in harsher environments is currently unknown.We examined evolutionary change in performance under drought, interspecific competition, and heat stress for populations of Arabidopsis thaliana that experienced six generations of spread through replicated experimental landscapes of favourable habitat. To quantify how population performance under stress differed between leading edge and founding populations, we combined individual tests of genotype performance under stress with knowledge of the genotype frequency changes that occurred over the replicate invasions.After spreading through favourable environments, the average silique production of individuals exposed to drought or interspecific competition was lower in leading edge than founding populations. This change was driven by the evolution of lower intrinsic silique production, which was correlated with increased seed size, a trait that evolved as populations spread. The ability of plants to tolerate drought or interspecific competition, however, did not change markedly during spread. Heat tolerance did increase in leading edge populations, and this trait was associated with the evolution of taller plants during spread through favourable habitat.Synthesis. We conclude that evolution during spread in favourable environments may affect the ability of populations to grow under stressful conditions as experienced in the expanded range, through changes in either intrinsic fecundity or stress tolerance. Thus, evolution during spread may constrain or extend the eventual range limit of nonnative species invasions. Spreading populations may rapidly evolve higher rates of dispersal and reproduction. However, they are likely to encounter stressful conditions in the expanded range. We found evolutionary changes in performance under stress for populations of Arabidopsis thaliana that invaded replicated experimental landscapes of favourable habitat. Our results suggest that evolution during spread may alter performance under stress, affecting further range expansion. [ABSTRACT FROM AUTHOR]

Abstract: Populations of range expanding species encounter patches of both favorable and unfavorable habitat as they spread across landscapes. Theory shows that increasing patchiness slows the spread of populations modeled with continuously varying population density when dispersal is not influence by the environment or individual behavior. However, as is found in uniformly favorable landscapes, spread remains driven by fecundity and dispersal from low density individuals at the invasion front. In contrast, when modeled populations are composed of discrete individuals, patchiness causes populations to build up to high density before dispersing past unsuitable habitat, introducing an important influence of density dependence on spread velocity. To test the hypothesized interaction between habitat patchiness and density dependence, we simultaneously manipulated these factors in a greenhouse system of annual plants spreading through replicated experimental landscapes. We found that increasing the size of gaps and amplifying the strength of density dependence both slowed spread velocity, but contrary to predictions, the effect of amplified density dependence was similar across all landscape types. Our results demonstrate that the discrete nature of individuals in spreading populations has a strong influence on how both landscape patchiness and density dependence influence spread through demographic and dispersal stochasticity. Both finiteness and landscape structure should be critical components to theoretical predictions of future spread for range expanding native species or invasive species colonizing new habitat. [ABSTRACT FROM AUTHOR]

Character displacement is one of the most studied phenomena in evolutionary biology, yet research has narrowly focused on demonstrating whether or not displacement has occurred. We propose a new experimental approach, adopted from the coexistence literature, that directly measures interspecific competition among sympatric and allopatric populations of species. Doing so allows increased ability to (i) test predictions of character displacement without biases inherent to character-centric tests, (ii) quantify its effect on the stability of coexistence, (iii) resolve the phenotypic pathways through which competitive divergence is achieved, and (iv) perform comparative tests. Our approach extends research to forms of character displacement not readily identified by past methods and will lead to a broader understanding of its consequences for community structure. [ABSTRACT FROM AUTHOR]

• Spatial variation in climate can drive variation in biocontrol efficacy of weeds. • Biocontrol of Dalmatian toadflax by weevils in stems more effective at warmer sites. • Biocontrol efficacy for Dalmatian toadflax predicted to increase along northern range. • Alternative to biocontrols likely needed at cooler sites to aid management. The effect of insect biological control agents on invasive plant populations can vary spatially, and spatial variation in climate may drive regional variation in herbivory, and thus biocontrol efficacy. Within host plant populations, local plant abundance can also be affected by the spatial distribution of herbivores, but whether local patterns persist at larger scales is less well understood. We examined how infestation and damage of the stem-mining weevil Mecinus janthiniformis , a specialist biocontrol agent of the invasive plant Linaria dalmatica , varied within and among populations across the northern edge of the range in North America. We quantified weevil and invasive plant densities, as well as plant fecundity, stem diameter and height across sites spanning an area of ∼39,000 km2 in British Columbia, Canada. We found that specialist weevils did not respond to host plant density within sites across the study region. Instead, weevil attack and load were most sensitive to among-site variability in climate, with stems at warmer sites having four times as many weevils compared to stems at cooler sites. Weevils also reduced plant fecundity more at warmer sites, when controlled for plant size (stem diameter) with larger effects of weevils in thicker stems, indicating that L. dalmatica suppression is highest in warmer locations where weevils are more abundant and environmental conditions more favorable. Our results suggest that, with climate change, the efficacy of biocontrol for L. dalmatica will improve across the northern edge of the range. We recommend that at cooler sites, where biocontrols are less prevalent and effects on plant fecundity are weaker, alternative management strategies are necessary at this time. Across invasive plant species more generally, future studies that establish the role of climate in variability in biocontrol efficacy long after introduction can improve management of invasive plants under climate change. [ABSTRACT FROM AUTHOR]

Predicting the speed of biological invasions and native species migrations requires an understanding of the ecological and evolutionary dynamics of spreading populations. Theory predicts that evolution can accelerate species’ spread velocity, but how landscape patchiness—an important control over traits under selection—influences this process is unknown. We manipulated the response to selection in populations of a model plant species spreading through replicated experimental landscapes of varying patchiness. After six generations of change, evolving populations spread 11% farther than nonevolving populations in continuously favorable landscapes and 200% farther in the most fragmented landscapes. The greater effect of evolution on spread in patchier landscapes was consistent with the evolution of dispersal and competitive ability. Accounting for evolutionary change may be critical when predicting the velocity of range expansions. [ABSTRACT FROM AUTHOR]

Predicting the spatial advance of biological invasions and range-shifting native species under climate change requires understanding how evolutionary processes influence the velocity of spread. Although landscape heterogeneity and the finite nature of individuals are known to influence the ecological dynamics of spreading populations, their effect on evolutionary dynamics influencing spread is poorly understood. We used adaptive dynamics and simulation approaches to evaluate the direction of selection on demographic and competitive traits in annual plant populations spreading through linear landscapes. In contrast to models in homogeneous environments where low-density fecundity is selectively favored, we found that large gaps between suitable habitat could favor the rise of competitively tolerant individuals at the invasion front, even when this ability to tolerate competitors came at the cost of reduced fecundity when rare. Simulations of the same processes incorporating finite individuals revealed a spatial priority effect; the long-term outcome of evolution strongly depended on which strategy initially got ahead. Finally, we found that although evolutionary change in demographic and competitive traits could increase the spread velocity, this increase could be insignificant in patchy landscapes, where competitive traits were favored in both spreading and nonspreading populations. [ABSTRACT FROM AUTHOR]

Using interview and self-administered survey data, this article examines how homes, schools, and the community spaces between these two locations affect adolescent nutrition in a low-income, urban setting. Results from this research show that eating location can play a significant role in the foods that adolescents consume. Food acquisition data provided by adolescents reveal that homes and schools provide spaces for the consumption of healthy foods while shops, restaurants, takeouts, and community centers contribute unhealthy snack foods to adolescent diets in a traditionally low-income, urban neighborhood in Northern Ireland. The results of this research show that eating location can provide a starting point for designing healthy eating interventions in low-income places to avoid overlap with spaces that already provide healthy foods to young people. [ABSTRACT FROM AUTHOR]

One of the key components of an organism's life history is the delay of reproduction until it reaches or returns to an optimal size. While we know climate can influence vital rates that shape life-history strategies, it is also critical to understand the effects of climate change on rapid life history evolution, which might modify the influence of climate change on population dynamics., We asked how realistic changes in temperature and precipitation influence vital rates, costs of reproduction, and ultimately, evolutionarily stable ( ES) flowering size in a long-lived perennial plant, Orchis purpurea. We also explored how evolution of flowering size could influence population persistence under changing climate., Our approach combined model selection methods to characterize climate dependence in vital rates, stochastic integral projection models to integrate vital rates into an estimate of fitness, and adaptive dynamics to identify ES flowering sizes., Vital rates responded uniquely to seasonal temperature and precipitation, with the largest response in the size-dependent probability of flowering. The predicted ES flowering size closely matched that observed, and responded strongly to adjusting the frequencies of extreme climate years. For example, increasing the frequency of extreme drought conditions was predicted to favour smaller reproductive sizes (and hence a shorter reproductive delay), despite observation that smaller plants were less likely to flower in dry years. This apparent discrepancy stems from a smaller payoff to delaying reproduction due to lower costs of reproduction in dry years., The model of stochastic population dynamics predicted long-term persistence of the focal populations, even under the most extreme climate scenarios, while incorporating rapid life history evolution into predictions reduced the sensitivity of population growth to changing climate., Synthesis. Our results illustrate that long-lived organisms can exhibit complex demographic responses to changing climate regimes. Additionally, they highlight that long-term evolutionary responses may be in opposing directions from short-term plastic responses to climate and emphasize the need for demographic models to integrate ecological and evolutionary influences of climate across the life cycle. [ABSTRACT FROM AUTHOR]

Understanding the factors influencing how fast populations can spread across the landscape will be crucial as species ranges shift due to climate change. While the role of abiotic factors in determining expansion speed has been well studied in theory and empirical research, how competition impacts speed has received far less attention. Here, we investigated how seed dispersal distances change in response to competition and how these changes to distributions of dispersed seeds impact expansion speed. We dispersed four genotypes of the annual plant Arabidopsis thaliana with variation in life history traits into greenhouse mesocosms of either empty habitat or habitat containing the annual grass competitor, Lolium multiflorum. We found that competition decreased both mean and maximum dispersal distance. We then built a simulation model of range expansion with experimental data from this and a prior experiment to explore whether competition slows species expansions primarily through decreasing dispersal or fecundity. We found that competition primarily slows expansion speed through decreases in dispersal, but that when competition impacts both dispersal and fecundity, expansions slow more than with dispersal alone. The genotype with traits associated with longer distance dispersal was the most affected by competition in both experimental dispersal and simulations. This research suggests that not only does competition slow range expansions through decreases in both fecundity and dispersal, but that there may be consequences for evolutionary processes at the leading edge. [ABSTRACT FROM AUTHOR]

Hyperthyroidism occurs secondary to overproduction of thyroid hormone by the thyroid gland. This condition can have rather serious effects on children, and thus timely diagnosis and treatment are of utmost importance. Imaging is quite useful in the management of children with hyperthyroidism. In addition to determining the underlying pathology, radiologic exams are crucial for therapy. This article describes the underlying etiologies of pediatric hyperthyroidism and provides general information on treatment. [ABSTRACT FROM AUTHOR]

Hypothyroidism, defined as inadequate production of thyroid hormone, can be secondary to various underlying abnormalities in the pediatric population. Most frequently, hypothyroidism is related to structural abnormalities of the gland (dysgenesis), particularly in the neonatal population. However, other etiologies including intrinsic biochemical (dyshormonogenesis) and autoimmune abnormalities, as well as other rare causes, must be considered. Imaging is required to differentiate among the various etiologies of hypothyroidism and can be helpful in guiding therapy. This review aims to present an organized approach to hypothyroidism in the pediatric population, and assist the imager in guiding patient care. [ABSTRACT FROM AUTHOR]

Integral projection models (IPMs) are increasingly being applied to study size-structured populations. Here we call attention to a potential problem in their construction that can have important consequences for model results. IPMs are implemented using an approximating matrix and bounded size range. Individuals near the size limits can be unknowingly “evicted” from the model because their predicted future size is outside the range. We provide simple measures for the magnitude of eviction and the sensitivity of the population growth rate (λ) to eviction, allowing modelers to assess the severity of the problem in their IPM. For IPMs of three plant species, we found that eviction occurred in all cases and caused underestimation of the population growth rate (λ) relative to eviction-free models; it is likely that other models are similarly affected. Models with frequent eviction should be modified because eviction is only possible when size transitions are badly mis-specified. We offer several solutions to eviction problems, but we emphasize that the modeler must choose the most appropriate solution based on an understanding of why eviction occurs in the first place. We recommend testing IPMs for eviction problems and resolving them, so that population dynamics are modeled more accurately. [ABSTRACT FROM AUTHOR]

Understanding the selective forces that shape reproductive strategies is a central goal of evolutionary ecology. Selection on the timing of reproduction is well studied in semelparous organisms because the cost of reproduction (death) can be easily incorporated into demographic models. Iteroparous organisms also exhibit delayed reproduction and experience reproductive costs, although these are not necessarily lethal. How non-lethal costs shape iteroparous life histories remains unresolved. We analysed long- term demographic data for the iteroparous orchid Orchis purpurea from two habitat types (light and shade). In both the habitats, flowering plants had lower growth rates and this cost was greater for smaller plants. We detected an additional growth cost of fruit production in the light habitat. We incorporated these non-lethal costs into integral projection models to identify the flowering size that maximizes fitness. In both habitats, observed flowering sizes were well predicted by the models. We also estimated optimal parameters for size-dependent flowering effort, but found a strong mismatch with the observed flower production. Our study highlights the role of context-dependent non-lethal reproductive costs as selective forces in the evolution of iteroparous life histories, and provides a novel and broadly applicable approach to studying the evolutionary demography of iteroparous organisms. [ABSTRACT FROM AUTHOR]

Summary 1. Matrix population models capture how variation in vital rates among life stages translates to population dynamics. Analyses of these models generally assume that populations have reached a stable stage distribution (SSD), where the proportion of individuals in each stage remains constant. However, when life stages respond differentially to environmental cues and perturbations, a population may be moved away from equilibrium. Given the multitude of stochastic processes acting in natural systems, populations may never be exactly at SSD. It is thus critical to understand how far away populations are from SSD and how distance from SSD influences near-term model projections. 2. We analysed published matrix models from 46 plant species spanning a range of life histories that reported both a current stage distribution and projection matrix. We examined the distance between observed and theoretical SSD and the associated consequences for near-term transient population dynamics for each species. 3. In the majority of studies, populations were near their expected SSD, with 80% falling within one unit of a projection distance (α0) of zero. This distribution was skewed towards positive values of α0, indicating that the majority of populations had individuals concentrated into stages with high reproductive values. 4. Half of the populations in our survey had projection distances such that transient projections of population size and growth rate were within 10% of asymptotic projections at 5 years. However, in populations where projection distance was > 2, deviations from SSD caused important (more than twofold) differences. 5. We also found that larger deviations from SSD were positively correlated with generation time and matrix size. 6. Synthesis. When some life stages within a plant population are more strongly affected by disturbances or stresses than others, the results of our literature survey suggest that equilibrium projections will tend to underestimate projections that account for the current stage distribution. Measuring the current stage distribution can help determine whether asymptotic measures of matrix model analyses are reliable, and is a crucial step to take when precise population metrics are necessary for guiding conservation and management. [ABSTRACT FROM AUTHOR]

Fitness costs of resistance to Bacillus thuringiensis (Bt) crops occur in the absence of Bt toxins, when individuals with resistance alleles are less fit than individuals without resistance alleles. As costs of Bt resistance are common, refuges of non- Bt host plants can delay resistance not only by providing susceptible individuals to mate with resistant individuals, but also by selecting against resistance. Because costs typically vary across host plants, refuges with host plants that magnify costs or make them less recessive could enhance resistance management. Limited understanding of the physiological mechanisms causing fitness costs, however, hampers attempts to increase costs. In several major cotton pests including pink bollworm (Pectinophora gossypiella), resistance to Cry1Ac cotton is associated with mutations altering cadherin proteins that bind this toxin in susceptible larvae. Here we report that the concentration of gossypol, a cotton defensive chemical, was higher in pink bollworm larvae with cadherin resistance alleles than in larvae lacking such alleles. Adding gossypol to the larval diet decreased larval weight and survival, and increased the fitness cost affecting larval growth, but not survival. Across cadherin genotypes, the cost affecting larval growth increased as the gossypol concentration of larvae increased. These results suggest that increased accumulation of plant defensive chemicals may contribute to fitness costs associated with resistance to Bt toxins. [ABSTRACT FROM AUTHOR]

Sleep disturbance is a common complaint in people with chronic pain, and is associated with a range of adverse outcomes including reports of greater pain and disability. Research into insomnia with chronic pain sufferers has not yet examined the role of psychological flexibility, a process from acceptance and commitment therapy. We examined this role. Participants in this study were 159 adult patients attending an assessment at a specialist pain center. They were mostly women, 63%, and the mean age was 43.8 years. In preliminary analyses 79% of participants met the criteria for significant insomnia based on their self-reported symptoms. As predicted, significant positive correlations were found between components of psychological flexibility, particularly acceptance of pain and values-based action, and all measures of sleep quality. In regression analyses, the components of psychological flexibility considered together accounted for between 11% and 19% of variance across a range of measures of sleep quality. These results suggest the need to further develop treatment services for people with chronic pain and insomnia. [ABSTRACT FROM AUTHOR]

A central question in ecology concerns how some exotic plants that occur at low densities in their native range are able to attain much higher densities where they are introduced. This question has remained unresolved in part due to a lack of experiments that assess factors that affect the population growth or abundance of plants in both ranges. We tested two hypotheses for exotic plant success: escape from specialist insect herbivores and a greater response to disturbance in the introduced range. Within three introduced populations in Montana, USA, and three native populations in Germany, we experimentally manipulated insect herbivore pressure and created small-scale disturbances to determine how these factors affect the performance of houndstongue (Cynoglossum officinale), a widespread exotic in western North America. Herbivores reduced plant size and fecundity in the native range but had little effect on plant performance in the introduced range. Small-scale experimental disturbances enhanced seedling recruitment in both ranges, but subsequent seedling survival was more positively affected by disturbance in the introduced range. We combined these experimental results with demographic data from each population to parameterize integral projection population models to assess how enemy escape and disturbance might differentially influence C. officinale in each range. Model results suggest that escape from specialist insects would lead to only slight increases in the growth rate (λ) of introduced populations. In contrast, the larger response to disturbance in the introduced vs. native range had much greater positive effects on λ. These results together suggest that, at least in the regions where the experiments were performed, the differences in response to small disturbances by C. officinale contribute more to higher abundance in the introduced range compared to at home. Despite the challenges of conducting experiments on a wide biogeographic scale and the logistical constraints of adequately sampling populations within a range, this approach is a critical step forward to understanding the success of exotic plants. [ABSTRACT FROM AUTHOR]

Invasive plants may respond through adaptive evolution and/or phenotypic plasticity to new environmental conditions where they are introduced. Although many studies have focused on evolution of invaders particularly in the context of testing the evolution of increased competitive ability (EICA) hypothesis, few consistent patterns have emerged. Many tests of the EICA hypothesis have been performed in only one environment; such assessments may be misleading if plants that perform one way at a particular site respond differently across sites. Single common garden tests ignore the potential for important contributions of both genetic and environmental factors to affect plant phenotype. Using a widespread invader in North America, Cynoglossum officinale, we established reciprocal common gardens in the native range (Europe) and introduced range (North America) to assess genetically based differences in size, fecundity, flowering phenology and threshold flowering size between native and introduced genotypes as well as the magnitude of plasticity in these traits. In addition, we grew plants at three nutrient levels in a pot experiment in one garden to test for plasticity across a different set of conditions. We did not find significant genetically based differences between native and introduced populations in the traits we measured; in our experiments, introduced populations of C. officinale were larger and more fecund, but only in common garden experiments in the native range. We found substantial population-level plasticity for size, fecundity and date of first flowering, with plants performing better in a garden in Germany than in Montana. Differentiation of native populations in the magnitude of plasticity was much stronger than that of introduced populations, suggesting an important role for founder effects. We did not detect evidence of an evolutionary change in threshold flowering size. Our study demonstrates that detecting genetically based differences in traits may require measuring plant responses to more than one environment. [ABSTRACT FROM AUTHOR]

Negative impacts of invasive plants on natives have been well documented, but much less is known about whether invasive plants can cause population level declines. We used demographic models to investigate the effects of two invasive grasses on the demography and population growth of Anemone patens, a long-lived native perennial of North American grasslands. Demographic data of A. patens growing in patches characterized by Bromus inermis, Poa pratensis, or native grasses were used to parameterize integral projection models. Models based on both average conditions and those allowing for environmental stochasticity indicate that A. patens is slowly increasing in patches of native grass (λ = 1.02) and declining in patches of invasive grasses, particularly those dominated, by B. inermis (λ = 0.93). Extinction probabilities indicate that A. patens should persist in native grass patches, but has a much higher probability of extinction in Bromus patches compared to Poa patches. While sensitivity analyses showed that survival had the biggest effect on population growth rates in all habitats, results of a Life Table Response Experiment (LTRE) revealed that slower individual growth rates in patches of invasive grasses contributed the most to the observed reduction in population growth. These results suggest that invasive grasses may cause slow declines in A. patens, despite short-term coexistence, and that controlling B. inermis only would not be sufficient to ensure A. patens persistence. [ABSTRACT FROM AUTHOR]

Objective: To assess health care providers (HCP) knowledge and practices regarding folic acid (FA) use for neural tube defect (NTD) prevention. Methods: Two identical surveys were conducted among 611 obstetricians/gynecologists (OB/GYNs) and family/general physicians (FAM/GENs) (2002), and 500 physician assistants (PAs), nurse practitioners (NPs), certified nurse midwives (CNMs), and registered nurses (2003) to ascertain knowledge and practices regarding FA. For analysis, T-tests, univariate and multivariate logistic regression modeling were used. Results: Universally, providers knew that FA prevents birth defects. Over 88% knew when a woman should start taking folic acid for the prevention of NTDs; and over 85% knew FA supplementation beyond what is available in the diet is necessary. However, only half knew that 50% of all pregnancies in the United States are unplanned. Women heard information about multivitamins or FA most often during well woman visits in obstetrical/gynecology (ob/gyn) practice settings (65%), and about 50% of the time during well woman visits in family/general (fam/gen) practice settings and 50% of the time at gynecology visits (both settings). Among all providers, 42% did not know the correct FA dosage (400 μg daily). HCPs taking multivitamins were more than twice as likely to recommend multivitamins to their patients (Odds Ratio [OR] 2.27 95%, Confidence Interval [CI] 1.75–2.94). HCPs with lower income clients (OR 1.49, CI 1.22–1.81) and HCPs with practices having more than 10% minorities (OR 1.46, CI 1.11–1.92) were more likely to recommend supplements. NPs in ob/gyn settings were most likely and FAM/GENs were least likely to recommend supplements (OR 3.06, CL 1.36–6.90 and OR 0.64, CL 0.45–0.90 respectively). Conclusions: Knowledge about birth defects and the necessity of supplemental FA was high. Increasing knowledge about unintended pregnancy rates and correct dosages of FA is needed. The strongest predictor for recommending the use of FA supplements was whether the provider took a multivitamin. [ABSTRACT FROM AUTHOR]

Growing season length can control plant size over altitudinal and biogeographic scales, but its effect at the scale of meters is largely unexplored. Within the riparian zone of a northern California river, scarlet monkeyflower, Mimulus cardinalis, grows significantly larger at sites high in the channel as compared to sites low in the channel, and even larger where tributaries meet the main stem of the river. We explored the hypothesis that markedly different growing season length controls this size variation. Due to the very gradual retreat of the water level following winter flooding, emergence time is three months longer for plants growing at tributary confluences than for plants growing at low elevations in the channel. Consistent with the growing season length hypothesis, we found no difference in transplant growth between river and tributary confluence sites in an experiment where we equalized growing season length at these locations. Moreover, a second experiment showed that individuals planted earlier in the year gain a distinct size advantage over those planted later, even though growing conditions are less ideal. These results suggest that emergence time may be a key determinant of plant size structure along rivers, an important result considering forecasted variation in water flows with climate change. [ABSTRACT FROM AUTHOR]

Describes the findings of a study that evaluated postal workers' adherence to anthrax postexposure prophylaxis at the regional mail facility in Connecticut in 2001. Factors influencing their degree of adherence; Characteristics of postal workers starting postexposure prophylaxis; Reasons for stopping anthrax postexposure prophylaxis.

Presents information on a study which examined variation in seven floral traits in wild radish, Raphanus raphanistrum at six levels of environment interaction. Methodology; Results and discussion.

Abstract: Although climate warming is expected to make habitat beyond species’ current cold range edge suitable for future colonization, this new habitat may present an array of biotic or abiotic conditions not experienced within the current range. Species’ ability to shift their range with climate change may therefore depend on how populations evolve in response to such novel environmental conditions. However, due to the recent nature of thus far observed range expansions, the role of rapid adaptation during climate change migration is only beginning to be understood. Here, we evaluated evolution during the recent native range expansion of the annual plant Dittrichia graveolens, which is spreading northward in Europe from the Mediterranean region. We examined genetically based differentiation between core and edge populations in their phenology, a trait that is likely under selection with shorter growing seasons and greater seasonality at northern latitudes. In parallel common garden experiments at range edges in Switzerland and the Netherlands, we grew plants from Dutch, Swiss, and central and southern French populations. Population genetic analysis following RAD‐sequencing of these populations supported the hypothesized central France origins of the Swiss and Dutch range edge populations. We found that in both common gardens, northern plants flowered up to 4 weeks earlier than southern plants. This differentiation in phenology extended from the core of the range to the Netherlands, a region only reached from central France over approximately the last 50 years. Fitness decreased as plants flowered later, supporting the hypothesized benefits of earlier flowering at the range edge. Our results suggest that native range expanding populations can rapidly adapt to novel environmental conditions in the expanded range, potentially promoting their ability to spread. [ABSTRACT FROM AUTHOR]

Dispersal is a central life history trait that affects the ecological and evolutionary dynamics of populations and communities. The recent use of experimental evolution for the study of dispersal is a promising avenue for demonstrating valuable proofs of concept, bringing insight into alternative dispersal strategies and trade‐offs, and testing the repeatability of evolutionary outcomes.Practical constraints restrict experimental evolution studies of dispersal to a set of typically small, short‐lived organisms reared in artificial laboratory conditions. Here, we argue that despite these restrictions, inferences from these studies can reinforce links between theoretical predictions and empirical observations and advance our understanding of the eco‐evolutionary consequences of dispersal.We illustrate how applying an integrative framework of theory, experimental evolution and natural systems can improve our understanding of dispersal evolution under more complex and realistic biological scenarios, such as the role of biotic interactions and complex dispersal syndromes. [ABSTRACT FROM AUTHOR]

Background While studies on mindfulness-based stress reduction ( MBSR) for youth have recently emerged, there is a shortage of research on how adolescents from clinical populations experience MBSR. The purpose of this qualitative study was to explore the impact of MBSR from the subjective perspective of adolescents with serious mental health concerns. Method Adolescents ( n = 28) from a residential treatment center participated in an adapted 8-week MBSR program in which they learned a range of mindfulness skills and were encouraged to apply the skills to their everyday lives. At the end of the program and at a 3-month follow-up, the youth participated in semistructured interviews in which they were asked to describe the impact of the program from their perspectives. Basic interpretive qualitative analysis methods were used to code the data and to group the codes into higher level themes. Results Six main themes were found, including improved mood, enhanced relationship to self, increased self-control, improved problem-solving, awareness of the present, and enhanced interpersonal relationships. Discussion Results from this study suggest that the MBSR program was perceived as beneficial both in the short-term and follow-up in several aspects of emotional, cognitive, and interpersonal functioning. [ABSTRACT FROM AUTHOR]

Background: Women of reproductive age are at an increased risk of anemia and micronutrient deficiencies. Evidence supports the role of periconceptional nutrition in the development of neural tube defects (NTDs) and other pregnancy complications. Vitamin B12 deficiency is a risk factor for NTDs and may modify folate biomarkers that predict NTD risk at the population level. There is an interest in mandatory fortification with vitamin B12 and folic acid for anemia and birth defect prevention. However, there are limited population-representative data needed to inform policy and guidelines. Objectives: This randomized trial will be conducted to evaluate the efficacy of quadruple-fortified salt (QFS; iron, iodine, folic acid, vitamin B12) in 1,000 households in Southern India. Methods: Women 18 to 49 y who are not pregnant or lactating and reside within the catchment area of our community-based research site in Southern India will be screened and invited to participate in the trial. After informed consent, women and their households will be randomized to receive one of the following 4 interventions: 1) double-fortified salt (DFS; iron, iodine), 2) DFS + folic acid (iron, iodine, folic acid), 3) DFS + vitamin B12 (iron, iodine, vitamin B12), or 4) DFS + folic acid and vitamin B12 (QFS; iron, iodine, folic acid, vitamin B12) for 12 mo. Structured interviews will be conducted by trained nurse enumerators to collect sociodemographic, anthropometric, dietary, health, and reproductive history data. Biological samples will be collected at baseline, midpoint, and endpoint. Whole blood will be analyzed for hemoglobin using Coulter Counter. Total vitamin B12 will be measured by chemiluminescence; red blood cell folate and serum folate will be evaluated using the World Health Organization-recommended microbiologic assay. Conclusions: The results of this randomized trial will help to evaluate the efficacy of QFS to prevent anemia and micronutrient deficiencies. Clinical trial registration numbers: NCT03853304 and Clinical Trial Registry of India REF/2019/03/024479. [ABSTRACT FROM AUTHOR]

Introduction: Population risk for neural tube defects (NTDs) can be determined using red blood cell (RBC) folate. However, a paucity of biomarker and surveillance data among non-lactating, non-pregnant women of reproductive age (NPWRA) from Africa limits accurate assessment. Our study assessed folate and vitamin B12 status among non-lactating NPWRA and predicted population risk of NTDs in Tanzania.A cross-sectional biomarker survey of non-lactating NPWRA (15–49 years) in the Morogoro region, Tanzania was conducted during June–October 2019. Questionnaire interview responses and non-fasting blood samples were collected. Folate was assessed using the CDC microbiologic assay kit and vitamin B12 was measured using an electrochemiluminescence immunoassay. Complex survey design analyses were conducted using SAS-callable SUDAAN (v11.0.1).Of the 761 participating non-lactating NPWRA, 294 (39.8%) had RBC folate insufficiency (<748 mol/L). The prevalence of RBC folate insufficiency was lower among non-lactating NPWRA living in urban than rural areas (PR: 0.72, 95% CI: 0.52–0.99) but did not differ by age or household wealth index. Vitamin B12 insufficiency was uncommon (< 221 pmol/L, 2.7%). The estimated NTD risk was 10.5 (95% uncertainty interval: 8.1–13.3) per 10,000 births.Elevated NTD risk was predicted in the Morogoro region of Tanzania, where ∼ 40% of non-lactating NPWRA had RBC folate insufficiency and < 3% had vitamin B12 insufficiency. The NTD risk is consistent with surveillance data for the area, limited folic acid fortification of staple foods, and low vitamin B12 insufficiency. Further studies are needed to better understand the context of these findings, especially the impact of micronutrient fortification in Tanzania.Methods: Population risk for neural tube defects (NTDs) can be determined using red blood cell (RBC) folate. However, a paucity of biomarker and surveillance data among non-lactating, non-pregnant women of reproductive age (NPWRA) from Africa limits accurate assessment. Our study assessed folate and vitamin B12 status among non-lactating NPWRA and predicted population risk of NTDs in Tanzania.A cross-sectional biomarker survey of non-lactating NPWRA (15–49 years) in the Morogoro region, Tanzania was conducted during June–October 2019. Questionnaire interview responses and non-fasting blood samples were collected. Folate was assessed using the CDC microbiologic assay kit and vitamin B12 was measured using an electrochemiluminescence immunoassay. Complex survey design analyses were conducted using SAS-callable SUDAAN (v11.0.1).Of the 761 participating non-lactating NPWRA, 294 (39.8%) had RBC folate insufficiency (<748 mol/L). The prevalence of RBC folate insufficiency was lower among non-lactating NPWRA living in urban than rural areas (PR: 0.72, 95% CI: 0.52–0.99) but did not differ by age or household wealth index. Vitamin B12 insufficiency was uncommon (< 221 pmol/L, 2.7%). The estimated NTD risk was 10.5 (95% uncertainty interval: 8.1–13.3) per 10,000 births.Elevated NTD risk was predicted in the Morogoro region of Tanzania, where ∼ 40% of non-lactating NPWRA had RBC folate insufficiency and < 3% had vitamin B12 insufficiency. The NTD risk is consistent with surveillance data for the area, limited folic acid fortification of staple foods, and low vitamin B12 insufficiency. Further studies are needed to better understand the context of these findings, especially the impact of micronutrient fortification in Tanzania.Results: Population risk for neural tube defects (NTDs) can be determined using red blood cell (RBC) folate. However, a paucity of biomarker and surveillance data among non-lactating, non-pregnant women of reproductive age (NPWRA) from Africa limits accurate assessment. Our study assessed folate and vitamin B12 status among non-lactating NPWRA and predicted population risk of NTDs in Tanzania.A cross-sectional biomarker survey of non-lactating NPWRA (15–49 years) in the Morogoro region, Tanzania was conducted during June–October 2019. Questionnaire interview responses and non-fasting blood samples were collected. Folate was assessed using the CDC microbiologic assay kit and vitamin B12 was measured using an electrochemiluminescence immunoassay. Complex survey design analyses were conducted using SAS-callable SUDAAN (v11.0.1).Of the 761 participating non-lactating NPWRA, 294 (39.8%) had RBC folate insufficiency (<748 mol/L). The prevalence of RBC folate insufficiency was lower among non-lactating NPWRA living in urban than rural areas (PR: 0.72, 95% CI: 0.52–0.99) but did not differ by age or household wealth index. Vitamin B12 insufficiency was uncommon (< 221 pmol/L, 2.7%). The estimated NTD risk was 10.5 (95% uncertainty interval: 8.1–13.3) per 10,000 births.Elevated NTD risk was predicted in the Morogoro region of Tanzania, where ∼ 40% of non-lactating NPWRA had RBC folate insufficiency and < 3% had vitamin B12 insufficiency. The NTD risk is consistent with surveillance data for the area, limited folic acid fortification of staple foods, and low vitamin B12 insufficiency. Further studies are needed to better understand the context of these findings, especially the impact of micronutrient fortification in Tanzania.Discussion: Population risk for neural tube defects (NTDs) can be determined using red blood cell (RBC) folate. However, a paucity of biomarker and surveillance data among non-lactating, non-pregnant women of reproductive age (NPWRA) from Africa limits accurate assessment. Our study assessed folate and vitamin B12 status among non-lactating NPWRA and predicted population risk of NTDs in Tanzania.A cross-sectional biomarker survey of non-lactating NPWRA (15–49 years) in the Morogoro region, Tanzania was conducted during June–October 2019. Questionnaire interview responses and non-fasting blood samples were collected. Folate was assessed using the CDC microbiologic assay kit and vitamin B12 was measured using an electrochemiluminescence immunoassay. Complex survey design analyses were conducted using SAS-callable SUDAAN (v11.0.1).Of the 761 participating non-lactating NPWRA, 294 (39.8%) had RBC folate insufficiency (<748 mol/L). The prevalence of RBC folate insufficiency was lower among non-lactating NPWRA living in urban than rural areas (PR: 0.72, 95% CI: 0.52–0.99) but did not differ by age or household wealth index. Vitamin B12 insufficiency was uncommon (< 221 pmol/L, 2.7%). The estimated NTD risk was 10.5 (95% uncertainty interval: 8.1–13.3) per 10,000 births.Elevated NTD risk was predicted in the Morogoro region of Tanzania, where ∼ 40% of non-lactating NPWRA had RBC folate insufficiency and < 3% had vitamin B12 insufficiency. The NTD risk is consistent with surveillance data for the area, limited folic acid fortification of staple foods, and low vitamin B12 insufficiency. Further studies are needed to better understand the context of these findings, especially the impact of micronutrient fortification in Tanzania. [ABSTRACT FROM AUTHOR]

Background Anemia is an important public health problem, and accurate estimates may inform policy and programs. Although hemoglobin (Hb) assessment of venous blood via automated hematology analyzers (AHAs) is recommended, most population-based surveys estimate anemia prevalence based on analysis of capillary blood via portable hemoglobinometers. Objectives We aimed to evaluate screening methods for hemoglobin and anemia assessment using paired venous samples. Methods Participants were women 15–40 y who were not pregnant or lactating. Paired venous whole blood samples (n  = 896) were analyzed for hemoglobin (Hb) via portable hemoglobinometer (HemoCue 301) and Coulter Counter AHA. Anemia and severe anemia were defined as Hb <12.0g/dL and <8.0 g/dL, respectively. Bland–Altman methods were used to assess the level of agreement for Hb results (mean difference, SD of differences, limits of agreement). Diagnostic accuracy parameters (sensitivity, specificity, positive predictive value, negative predictive value, accuracy) were calculated to evaluate HemoCue performance compared to the AHA reference, overall and by sociodemographic, nutritional, and metabolic characteristics. Results The estimated anemia prevalence was significantly lower via HemoCue vs. AHA (36.3% compared with 41.6%; P value < 0.0001). The HemoCue had 84.4% accuracy for anemia screening and 98.8% for severe anemia, compared to the AHA reference. The HemoCue had 74.8% sensitivity and 91.2% specificity, compared to AHA. HemoCue sensitivity was higher in women with iron deficiency [serum ferritin (SF) <15.0 μg/L: 81.6% compared with SF ≥15.0 μg/L: 41.3%], and lower in women with metabolic risk factors, including overweight [BMI ≥25.0 kg/m2: 63.9% vs. BMI <25.0 kg/m2: 78.8%], or elevated CRP (>1.0 mg/L: 67.2% vs. ≤1.0 mg/L: 82.9%), trunk fat (>35%: 62.7% vs. ≤35%: 80.1%), or whole-body fat (>35%: 63.9% vs. ≤35%: 80.3%). Conclusions Findings suggest that women with anemia may be incorrectly identified as not anemic via portable hemoglobinometer, and anemia prevalence may be underestimated at the population level. This study was registered at clinicaltrials.gov as NCT04048330. [ABSTRACT FROM AUTHOR]

Demographic transition matrices are among the most commonly applied population models for both basic and applied ecological research. The relatively simple framework of these models and simple, easily interpretable summary statistics they produce have prompted the wide use of these models across an exceptionally broad range of taxa. Here, we provide annual transition matrices and observed stage structures/population sizes for 20 perennial plant species which have been the focal species for long-term demographic monitoring. These data were assembled as part of the "Testing Matrix Models" working group through the National Center for Ecological Analysis and Synthesis (NCEAS). The data represent 82 populations with >460 total population-years of observations. It is our hope that making these data available will help promote and improve our ability to monitor and understand plant population dynamics. [ABSTRACT FROM AUTHOR]

For three decades, the US Public Health Service has recommended that all persons capable of becoming pregnant consume 400 μg/day of folic acid (FA) to prevent neural tube defects (NTDs). The neural tube forms by 28 days after conception. Fortification can be an effective NTD prevention strategy in populations with limited access to folic acid foods and/or supplements. This review describes the status of mandatory FA fortification among countries that fortify (n = 71) and the research describing the impact of those programs on NTD rates (up to 78% reduction), blood folate concentrations [red blood cell folate concentrations increased ∼1.47-fold (95% CI, 1.27, 1.70) following fortification], and other health outcomes. Across settings, high-quality studies such as those with randomized exposures (e.g., randomized controlled trials, Mendelian randomization studies) are needed to elucidate interactions of FA with vitamin B12 as well as expanded biomarker testing. [ABSTRACT FROM AUTHOR]

The authors describe the contribution of nurses at the U.S. Centers for Disease Control and Prevention (CDC) during the COVID-19 pandemic. Topics include the significance of nurses to the workforce of many health care organizations, roles and contributions of CDC nurses that parallel the work of dedicated public health nurses at state and local health departments, and factors that will strengthen nurse resilience, which is essential for sustaining the nursing workforce.

The article focuses on use of species invasions in determining plant biology including impacts of climate change on evolution of plant species; use of species invasions in determining adaptation of plant species into changing conditions; and impact of biotic interactions on plant biology.

Context: Navicular drop is widely believed to be an indicator of elevated susceptibility to pronation-related injuries, which may be increased by fatigue in the muscles that dynamically support the medial longitudinal arch. Objective: The purpose of this study was to evaluate navicular drop before and after fatigue of the ankle invertor muscles among individuals with different foot types. Participants: 20 male and 16 female recreationally active, college-age volunteers (20.03 ± 1.48 years of age). Methods: Navicular drop was measured before and after inducing fatigue in the ankle invertor muscles. Participants' foot types were classified as high-arch, neutral, or low-arch. Results: There was no interaction between foot type and trial, and no main effect for trial. A main effect for foot type was significant (p = .001). Intra-class correlation coefficients for prefatigue and postfatigue measurements indicated good internal consistency. Conclusion: Our findings failed to provide any evidence to support the existence of a relationship between ankle invertor muscle fatigue and static measurements of change in navicular height from a sitting to standing position. [ABSTRACT FROM AUTHOR]

Context: Navicular drop is widely believed to be an indicator of elevated susceptibility to pronation-related injuries, which may be increased by fatigue in the muscles that dynamically support the medial longitudinal arch. Objective: The purpose of this study was to evaluate navicular drop before and after fatigue of the ankle invertor muscles among individuals with different foot types. Participants: 20 male and 16 female recreationally active, college-age volunteers (20.03 ± 1.48 years of age). Methods: Navicular drop was measured before and after inducing fatigue in the ankle invertor muscles. Participants' foot types were classified as high-arch, neutral, or low-arch. Results: There was no interaction between foot type and trial, and no main effect for trial. A main effect for foot type was significant (p = .001). Intra-class correlation coefficients for prefatigue and postfatigue measurements indicated good internal consistency. Conclusion: Our findings failed to provide any evidence to support the existence of a relationship between ankle invertor muscle fatigue and static measurements of change in navicular height from a sitting to standing position. [ABSTRACT FROM AUTHOR]

Forecasting how climate change will impact biological systems represents a grand challenge for biologists. However, climate change biology lacks an effective framework for anticipating and resolving uncertainty. Here, we introduce the concept of climate change wildcards: biological or bioclimatic processes with a high degree of uncertainty and a large impact on our ability to address the biotic consequences of climate change. Wildcards may occur at multiple points in the progression of research—from understanding, to predicting, to forecasting biological responses. Our understanding of biological responses is limited by the components and processes we exclude to make research tractable. Our ability to predict biological responses often requires integration between biological levels of organization, across multiple stressors, and from specific cases to general systems. However, these types of integration can be dramatically affected by, respectively, differences between biological levels in their critical points, nonadditivity of the effects of different stressors, and historical and geographic contingency. Finally, our ability to forecast biological responses to climate change requires incorporating climatic projections in bioclimatic models. Such forecasts are vulnerable to the compounding of biological and climatic uncertainty, especially when biological responses occur in novel areas of bioclimatic parameter space. Both biological responses and climate change are dynamic processes; the potential of biological systems to be buffered against or rescued from the effects of climate change depends on the relative timing of biological and climatic effects—one of the least predictable aspects of both systems. In sum, our framework identifies stress points in the research process where we should anticipate and forestall wildcards. Focusing on universal currencies, like energy and elements, and universal structures, like functional traits and ecological networks, will improve our ability to generalize results. Most importantly, by modeling and communicating uncertainty, climate change biology can identify critical foci for future research. [ABSTRACT FROM AUTHOR]

1. Despite a large literature documenting the effects of mutualists and/or antagonists on plant performance, we still have limited insight into the strength of these interactions, as this involves quantifying how one species influences the population dynamics of another. 2. Here, we use data from two example systems, Cynoglossum officinale and Calathea ovandensis, to illustrate how experiments, demographic data and stage-based population models can be combined to estimate interaction strength of insect herbivores on plants. Because many plant populations may not be at equilibrium, we conduct transient analyses and contrast these results to more traditional asymptotic results. 3. We calculate three metrics of interaction strength, Δλasymptotic, the change in asymptotic annual per capita plant population growth rate resulting from herbivore exclusion, Δ λ( t), the change in transient λ caused by herbivores at t = M (where M = the time of their maximum effect during the transient phase) and Δ λtransient, a time-averaged effect of consumers on λ across the entire transient phase. 4. Fairly strong impacts of insect consumers on plant fecundity do not translate similarly to Δλasymptotic. Results show that Δ λ( t) can be larger (or smaller) than Δλasymptotic but in our examples Δ λtransient was similar in magnitude to Δλasymptotic. 5. The transient effects of consumers on λ were driven by changes in the elasticity of fecundity across the transient phase. These effects were dynamic even though consumer impacts on demography and vital rates were held constant. The importance of particular stages and transitions to annual population growth vary during the transient phase. 6. Synthesis. We describe three metrics of interaction strength, Δ λasymptotic, Δ λ( t) and Δ λtransient. These metrics have several advantages over more commonly used trait or performance measures that quantify the outcome of interactions. We illustrate how the transient impacts of consumers on λ are dynamic, with the changing stage distribution of a population and transient elasticities driving these effects. More generally, this study shows that the impacts of animals on plant performance do not translate equivalently to plant population growth, thereby underscoring the importance of using population models to extend the inference of individual-level experiments. [ABSTRACT FROM AUTHOR]

Background Women of reproductive age (WRA) are a high-risk population for anemia and micronutrient deficiencies. However, there are few representative population-level data from India, which could help inform evidence-based recommendations and policy. Objective To conduct a population-based biomarker survey of anemia and vitamin B-12 and folate status in WRA as part of a periconceptional surveillance program in southern India. Methods Participants were WRA (15–40 y) who were not pregnant or lactating. Whole blood (n  = 979) was analyzed for hemoglobin via a Coulter counter (Coulter HMX). Plasma, serum, and RBCs were processed and stored at −80°C or less until batch analysis. Vitamin B-12 concentrations were measured via chemiluminescence; RBC and serum folate concentrations were evaluated via microbiological assay. Anemia and severe anemia were defined as hemoglobin <12.0 g/dL and <8.0 g/dL, respectively. Vitamin B-12 deficiency and insufficiency were defined as total vitamin B-12 <148 pmol/L and <221 pmol/L, respectively. Folate deficiency and insufficiency were defined as RBC folate <305 nmol/L and <748 nmol/L. A previously developed Bayesian model was used to predict neural tube defect (NTD) prevalence per 10,000 births. Results A total of 41.5% of WRA had anemia and 3.0% had severe anemia. A total of 48.3% of WRA had vitamin B-12 deficiency and 74.3% had vitamin B-12 insufficiency. The prevalence of RBC folate deficiency was 7.6%, and 79.3% of WRA had RBC folate <748 nmol/L, the threshold for optimal NTD prevention. Predicted NTD prevalence per 10,000 births based on RBC folate concentrations was 20.6 (95% uncertainty interval: 16.5–25.5). Conclusions The substantial burden of anemia, vitamin B-12 deficiency, and RBC folate insufficiency in WRA in this setting suggests an opportunity for anemia and birth defects prevention. Findings will directly inform the development of a randomized trial for anemia and birth defects prevention in southern India. This study was registered at clinicaltrials.gov as NCT04048330. [ABSTRACT FROM AUTHOR]

Understanding the movement of species' ranges is a classic ecological problem that takes on urgency in this era of global change. Historically treated as a purely ecological process, range expansion is now understood to involve eco‐evolutionary feedbacks due to spatial genetic structure that emerges as populations spread. We synthesize empirical and theoretical work on the eco‐evolutionary dynamics of range expansion, with emphasis on bridging directional, deterministic processes that favor evolved increases in dispersal and demographic traits with stochastic processes that lead to the random fixation of alleles and traits. We develop a framework for understanding the joint influence of these processes in changing the mean and variance of expansion speed and its underlying traits. Our synthesis of recent laboratory experiments supports the consistent role of evolution in accelerating expansion speed on average, and highlights unexpected diversity in how evolution can influence variability in speed: results not well predicted by current theory. We discuss and evaluate support for three classes of modifiers of eco‐evolutionary range dynamics (landscape context, trait genetics, and biotic interactions), identify emerging themes, and suggest new directions for future work in a field that stands to increase in relevance as populations move in response to global change. [ABSTRACT FROM AUTHOR]

Introduction: Appendiceal duplication is a rare anomaly that can manifest as right lower quadrant pain. There are several variations described for this condition. We recommend aggressive operative management should this anatomical variation present in the presence of acute appendicitis.Case Presentation: We report the case of a 15-year-old African American girl who presented to our hospital with right lower quadrant pain and was subsequently found to have appendiceal duplication.Conclusion: There are two categorical systems that have described and stratified appendiceal duplication. Both classification systems have been outlined and referenced in this case report. A computed tomography scan has been included to provide a visual aid to help identify true vermiform appendiceal duplication. The presence of this anatomical abnormality is not a reason for surgical intervention; however, should this be found in the setting of acute appendicitis, aggressive resection of both appendices is mandatory. [ABSTRACT FROM AUTHOR]