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A major restriction in predicting plant community response to future climate change is a lack of long-term data needed to properly assess species and community response to climate and identify a baseline to detect climate anomalies. Here, we use a 106-year dataset on a Sonoran Desert plant community to test the role of extreme temperature and precipitation anomalies on community dynamics at the decadal scale and over time. Additionally, we tested the climate sensitivity of 39 desert plant species and whether sensitivity was associated with growth form, longevity, geographic range, or local dominance. We found that desert plant communities had shifted directionally over the 106 years, but the climate had little influence on this directional change primarily due to nonlinear shifts in precipitation anomalies. Decadal-scale climate had the largest impact on species richness, species relative density, and total plant cover, explaining up to 26%, 45%, and 55% of the variance in each, respectively. Drought and the interaction between the frequency of freeze events and above-average summer precipitation were among the most influential climate factors. Increased drought frequency and wetter periods with frequent freeze events led to larger reductions in total plant cover, species richness, and the relative densities of dominant subshrubs Ambrosia deltoidea and Encelia farinosa. More than 80% of the tested species were sensitive to climate, but sensitivity was not associated with a species' local dominance, longevity, geographic range, or growth form. Some species appear to exhibit demographic buffering, where when they have a higher sensitivity to drought, they also tend to have a higher sensitivity to favorable (i.e., wetter and hotter) conditions. Overall, our results suggest that, while decadal-scale climate variation substantially impacts these desert plant communities, directional change in temperature over the last century has had little impact due to the relative importance of precipitation and drought. With projections of increased drought in this region, we may see reductions in total vegetation cover and species richness due to the loss of species, possibly through a breakdown in their ability to demographically buffer climatic variation, potentially changing community dynamics through a change in facilitative and competitive processes. [ABSTRACT FROM AUTHOR]

Competition over resources often leads to intra‐ and interspecific interactions, which can be detrimental to the individuals involved. Thus, natural selection should favor communication systems that reliably convey information regarding the relative competitive abilities of an individual, reducing the need for physically damaging confrontation. Body size, sex, age, relatedness, and ornamentation are important factors determining dominance across diverse taxa in intraspecific interactions. These traits, when perceptible, may serve as signals across species in guilds that have frequent interspecific interactions. Hummingbirds provide a tractable system to study such community dynamics due to their high frequency of interactions, variable ornamentation, diverse body sizes, fast metabolism, and large overlap in resource utilization. Even in this system, potential interactions between morphology and coloration are rarely accounted for together when analyzing dominance between species. We take a novel approach to understanding interspecific dominance by assessing behavior, morphology, and coloration across different types of behavioral interactions. Across 11 tropical montane hummingbird species, we find that dominance is predicted by wing size and some metrics of plumage coloration. However, the biological significance of these factors varies between the different dominance behaviors performed. These results inform our understanding of interspecific signaling and its role in the evolution of intraguild communication and resource competition. [ABSTRACT FROM AUTHOR]

American Sign Language (ASL) education is a relatively new field. Thus, further research is necessary, especially regarding developing assessment tools. The goal of this study was to determine the types of assessment tools ASL level 1 teachers use in the classroom and how those teachers measure students' language progression. This study is critical because no standard ASL level 1 assessment tool measures students' skill levels to advance to the next level. The survey was created to build a better understanding of what tools ASL instructors use to assess their students' language performance. Data were collected from 93 ASL level 1 teachers. The results demonstrated a need for additional training for ASL teachers to improve their knowledge of language assessments and skills in using assessment tools, especially to support ASL students' language progress and proficiency. The results of this study provide suggestions for future assessment tools to increase the effectiveness of ASL programs across the United States. The Challenge: American Sign Language (ASL) is the third most studied language in the United States; however, the types of assessment tools used in ASL classrooms remains unclear. Thus, this study investigated the types of assessments that ASL instructors use to enhance ASL performance results. [ABSTRACT FROM AUTHOR]

Pharmacists in the community and ambulatory settings are primed for collaboration that can optimize care. Now is the time to capitalize on the momentum and positive disruption of the COVID‐19 pandemic that propelled pharmacists and their organizations to respond with agility to deliver care in new ways, pivot to develop new partnerships, and leverage technology. The growth of collaborative practice agreements within ambulatory care settings, the enhancement of clinically integrated networks, and the growth in professional organization support create an environment ripe for implementation of pharmacist‐to‐pharmacist collaborations. The American College of Clinical Pharmacy 2022 Clinical Practice Affairs B Committee sought out literature, as well as prepublication contemporary examples, demonstrating models of intraprofessional collaboration among pharmacists in community and ambulatory settings. The committee formulated six key recommendations to optimize pharmacist collaborations in the community and ambulatory settings and formed a framework for practical implementation strategies at the levels of individual pharmacists, organizations, and educational institutions and for legislative advocacy. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Coexistence of TGM1 and FLG mutations in a newborn with congenital ichthyosis is not well described in the literature. Early genetic testing and counseling are crucial for accurate diagnosis and appropriate management. Further exploration of associated problems, including hearing loss and developmental delay, is warranted in patients with these mutations. [ABSTRACT FROM AUTHOR]

Animals eavesdrop on signals and cues generated by prey, predators, hosts, parasites, competing species, and conspecifics, and the conspicuousness of sexual signals makes them particularly susceptible. Yet, when sexual signals evolve, most attention is paid to impacts on intended receivers (potential mates) rather than fitness consequences for eavesdroppers. Using the rapidly evolving interaction between the Pacific field cricket, Teleogryllus oceanicus, and the parasitoid fly, Ormia ochracea, we asked how parasitoids initially respond to novel changes in host signals. We recently discovered a novel sexual signal, purring song, in Hawaiian populations of T. oceanicus that appears to have evolved because it protects the cricket from the parasitoid while still allowing males to attract female crickets for mating. In Hawaii, there are no known alternative hosts for the parasitoid, so we would expect flies to be under selection to detect and attend to the new purring song. We used complementary field and laboratory phonotaxis experiments to test fly responses to purring songs that varied in many dimensions, as well as to ancestral song. We found that flies strongly prefer ancestral song over purring songs in both the field and the lab, but we caught more flies to purring songs in the field than reported in previous work, indicating that flies may be exerting some selective pressure on the novel song. When played at realistic amplitudes, we found no preferences–flies responded equally to all purrs that varied in frequency, broadbandedness, and temporal measures. However, our lab experiment did reveal the first evidence of preference for purring song amplitude, as flies were more attracted to purrs played at amplitudes greater than naturally occurring purring songs. As purring becomes more common throughout Hawaii, flies that can use purring song to locate hosts should be favored by selection and increase in frequency. [ABSTRACT FROM AUTHOR]

Selection and effort are central to attention, yet it is unclear whether they draw on a common pool of cognitive resources, and if so, whether there are differences for early versus later stages of cognitive processing. This study assessed effort by quantifying the vigilance decrement, and spatial processing at early and later stages as a function of time‐on‐task. Participants performed an auditory spatial attention task, with occasional "catch" trials requiring no response. Psychophysiological measures included bilateral cerebral blood flow (transcranial Doppler), pupil dilation, and blink rate. The shape of attention gradients using reaction time indexed early processing, and did not significantly vary over time. Later stimulus‐response conflict was comparable over time, except for a reduction to left hemispace stimuli. Target and catch trial accuracy decreased with time, with a more abrupt decrease for catch versus target trials. Diffusion decision modeling found progressive decreases in information accumulation rate and non‐decision time, and the adoption of more liberal response criteria. Cerebral blood flow increased from baseline and then decreased over time, particularly in the left hemisphere. Blink rate steadily increased over time, while pupil dilation increased only at the beginning and then returned towards baseline. The findings suggest dissociations between resources for selectivity and effort. Measures of high subjective effort and temporal declines in catch trial accuracy and cerebral blood flow velocity suggest a standard vigilance decrement was evident in parallel with preserved selection. Different attentional systems and classes of computations that may account for dissociations between selectivity versus effort are discussed. This study probed the relations between auditory attentional selection and effort by examining selectivity of spatial processing at early and later cognitive stages as a function of effort during the vigilance decrement. The results showed dissociations between attentional selection and vigilance effort using behavioral, diffusion decision modeling, and psychophysiological measures. Potential differences in the cognitive computations that underlie selection and effort are discussed as they relate to the observed dissociations. [ABSTRACT FROM AUTHOR]

Background: Lactic acid bacteria are commensal members of the gut microbiota and are postulated to promote host health. Secreted factors and cell surface components from Lactobacillus species have been shown to modulate the host immune system. However, the precise role of L. reuteri secreted factors and surface proteins in influencing dendritic cells (DCs) remains uncharacterized. Hypothesis: We hypothesize that L. reuteri secreted factors will promote DC maturation, skewing cells toward an anti‐inflammatory phenotype. In acute colitis, we speculate that L. reuteri promotes IL‐10 and dampens pro‐inflammatory cytokine production, thereby improving colitis. Methods & Results: Mouse bone marrow‐derived DCs were differentiated into immature dendritic cells (iDCs) via IL‐4 and GM‐CSF stimulation. iDCs exposed to L. reuteri secreted factors or UV‐irradiated bacteria exhibited greater expression of DC maturation markers CD83 and CD86 by flow cytometry. Additionally, L. reuteri stimulated DCs exhibited phenotypic maturation as denoted by cytokine production, including anti‐inflammatory IL‐10. Using mouse colonic organoids, we found that the microinjection of L. reuteri secreted metabolites and UV‐irradiated bacteria was able to promote IL‐10 production by DCs, indicating potential epithelial‐immune cross‐talk. In a TNBS‐model of acute colitis, L. reuteri administration significantly improved histological scoring, colonic cytokine mRNA, serum cytokines, and bolstered IL‐10 production. Conclusions: Overall these data demonstrate that both L. reuteri secreted factors and its bacterial components are able to promote DC maturation. This work points to the specific role of L. reuteri in modulating intestinal DCs. New & Noteworthy: Lactobacillusreuteri colonizes the mammalian gastrointestinal tract and exerts beneficial effects on host health. However, the mechanisms behind these effects have not been fully explored. In this article, we identified that L. reuteri ATTC PTA 6475 metabolites and surface components promote dendritic cell maturation and IL‐10 production. In acute colitis, we also demonstrate that L. reuteri can promote IL‐10 and suppress inflammation. These findings may represent a crucial mechanism for maintaining intestinal immune homeostasis. [ABSTRACT FROM AUTHOR]

Where land surface air temperature data are not available, satellite land surface temperature are used. However, the coarse spatial resolution of satellite‐derived products may yield errors at the local scale. This work shows the differences between the MODIS Land Surface Temperature and Emissivity (MOD11A1) product and ground measurements at two different scales. We used data from 21 SNOTEL stations across the northern Front Range of Colorado to represent the coarse scale and 17 iButton temperature sensors across the Colorado State University Mountain Campus to represent the fine scale. We found significant differences in the temperature and its changes with elevation for the two spatial scales. At the fine scale, cold air drainage can induce an inversion of the temperature gradient with elevation. A higher correlation was found during the nighttime at the fine scale, while, at the coarse scale, higher correlations were observed during the daytime. On windy nights, temperatures do not cool as much as on calmer nights, and the coarse scale near‐surface temperature gradient with elevation persists, though the fine scale inversions do not develop. The near‐surface temperature gradients with elevation based on the MODIS pixels are similar to the ground‐based data at the coarse scale but not at the fine scale. Thus, one must be cautious in selecting the near‐surface temperature gradients with elevation for mountainous terrain when different scales are considered, and a proper validation of satellite products is necessary prior to their use to avoid the propagation of uncertainties. [ABSTRACT FROM AUTHOR]

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Key points: Enteroids are a physiologically relevant model to examine the human intestine and its functions.Previously, the measurable cytokine response of human intestinal enteroids has been limited following exposure to host or microbial pro‐inflammatory stimuli.Modifications to enteroid culture conditions facilitated robust human cytokine responses to pro‐inflammatory stimuli.This new human enteroid culture methodology refines the ability to study microbiome:human intestinal epithelium interactions in the laboratory. The intestinal epithelium is the primary interface between the host, the gut microbiome and its external environment. Since the intestinal epithelium contributes to innate immunity as a first line of defence, understanding how the epithelium responds to microbial and host stimuli is an important consideration in promoting homeostasis. Human intestinal enteroids (HIEs) are primary epithelial cell cultures that can provide insights into the biology of the intestinal epithelium and innate immune responses. One potential limitation of using HIEs for innate immune studies is the relative lack of responsiveness to factors that stimulate epithelial cytokine production. We report technical refinements, including removal of extracellular antioxidants, to facilitate enhanced cytokine responses in HIEs. Using this new method, we demonstrate that HIEs have distinct cytokine profiles in response to pro‐inflammatory stimuli derived from host and microbial sources. Overall, we found that host‐derived cytokines tumour necrosis factor and interleukin‐1α stimulated reactive oxygen species and a large repertoire of cytokines. In contrast, microbial lipopolysaccharide, lipoteichoic acid and flagellin stimulated a limited number of cytokines and histamine did not stimulate the release of any cytokines. Importantly, HIE‐secreted cytokines were functionally active, as denoted by the ability of human blood‐derived neutrophil to migrate towards HIE supernatant containing interleukin‐8. These findings establish that the immune responsiveness of HIEs depends on medium composition and stimuli. By refining the experimental culture medium and creating an environment conducive to epithelial cytokine responses by human enteroids, HIEs can facilitate exploration of many experimental questions pertaining to the role of the intestinal epithelium in innate immunity. Key points: Enteroids are a physiologically relevant model to examine the human intestine and its functions.Previously, the measurable cytokine response of human intestinal enteroids has been limited following exposure to host or microbial pro‐inflammatory stimuli.Modifications to enteroid culture conditions facilitated robust human cytokine responses to pro‐inflammatory stimuli.This new human enteroid culture methodology refines the ability to study microbiome:human intestinal epithelium interactions in the laboratory. [ABSTRACT FROM AUTHOR]

Offspring polymorphism is a reproductive strategy where individual organisms simultaneously produce offspring that differ in morphology and ecology. It occurs across the Tree of Life but is particularly common among plants, where it is termed seed (diaspore) heteromorphism. The prevalence of this strategy in unpredictably varying environments has resulted in the assumption that it serves as a bet‐hedging mechanism. We found 101 examples of this strategy in southwestern North America. We provide phylogenetically informed evidence for the hypothesis that the occurrence of seed heteromorphism increases with increasing environmental variability, though this pattern was only significant for aridity, one of our two rainfall variability metrics. We provide a strong test of bet hedging for a large, taxonomically diverse set of seed heteromorphic species, lending support to the hypothesis that bet hedging is an important mechanistic driver for the evolution of seed heteromorphism. [ABSTRACT FROM AUTHOR]

Objectives: Sodium, a vital micronutrient that is often in scarce supply for tropical herbivores, is sometimes found at high concentration in decaying wood. We tested two hypotheses for chimpanzees: first, that wood‐eating facilitates acquisition of sodium; second, that wood‐eating occurs in response to the low availability of sodium from other dietary sources. Materials and Methods: We studied the behavior of more than 50 chimpanzees of all age‐sex classes in the Kanyawara community of Kibale National Park, Uganda. We quantified the sodium content of dietary items, including wood samples from tree species that chimpanzees consumed or did not consume. To assess variation in sodium intake, we used 7 years of data on time spent feeding on plant foods, 18 months of data on rates of food intake by adult females, and 20 years of data on meat‐eating. Results: Major dietary sources of sodium were wood, fruits and meat. Chimpanzees consumed wood primarily from decaying trees of Neoboutonia macrocalyx (Euphorbiaceae), which had substantially higher sodium content than all other dietary items tested. Wood‐eating was negatively correlated with fruit‐eating. Females ate wood more often than males, while males had a greater probability of consuming meat at predation events. Discussion We propose that females ate wood more often than males because females had reduced access to meat, their preferred source of sodium. This hypothesis suggests that the need for sodium is a motivating reason for chimpanzees to consume both meat and wood. [ABSTRACT FROM AUTHOR]

Plant germination ecology involves continuous interactions between changing environmental conditions and the sensitivity of seed populations to respond to those conditions at a given time. Ecologically meaningful parameters characterizing germination capacity (or dormancy) are needed to advance our understanding of the evolution of germination strategies within plant communities. The germination traits commonly examined (e.g., maximum germination percentage under optimal conditions) may not adequately reflect the critical ecological differences in germination behavior across species, communities, and seasons. In particular, most seeds exhibit primary dormancy at dispersal that is alleviated by exposure to dry after‐ripening or to hydrated chilling to enable germination in a subsequent favorable season. Population‐based threshold (PBT) models of seed germination enable quantification of patterns of germination timing using parameters based on mechanistic assumptions about the underlying germination physiology. We applied the hydrothermal time (HTT) model, a type of PBT model that integrates environmental temperature and water availability, to study germination physiology in a guild of coexisting desert annual species whose seeds were after‐ripened by dry storage under different conditions. We show that HTT assumptions are valid for describing germination physiology in these species, including loss of dormancy during after‐ripening. Key HTT parameters, the hydrothermal time constant (θHT) and base water potential distribution among seeds (Ψb(g)), were effective in describing changes in dormancy states and in clustering species exhibiting similar germination syndromes. θHT is an inherent species‐specific trait relating to timing of germination that correlates well with long‐term field germination fraction, while Ψb(g) shifts with depth of dormancy in response to after‐ripening and seasonal environmental variation. Predictions based on variation among coexisting species in θHT and Ψb(g) in laboratory germination tests matched well with 25‐yr observations of germination dates and fractions for the same species in natural field conditions. Seed dormancy and germination strategies, which are significant contributors to long‐term species demographics under natural conditions, can be represented by readily measurable functional traits underlying variation in germination phenologies. [ABSTRACT FROM AUTHOR]

Phosphoinositide 3-kinases, delta (PI3Kδ) and gamma (PI3Kγ) are enriched in immune cells and regulate the development and function of innate and adaptive immunity. Dual PI3Kδγ inhibitors are considered high value targets for their potential to treat a variety of immune-mediated diseases, but their discovery has been challenging. Here we describe the preclinical pharmacology of HM5023507, an orally active dual inhibitor of δγ isoforms in immune signaling. HM5023507 inhibited PI3Kδ and PI3Kγ isoforms with greater than 100-fold selectivity against PI3Kα and PI3Kβ in recombinant enzymatic assays and in primary human immune cells with an exquisite selectivity against other targets. HM5023507 attenuated the PI3Kδ/γ signaling in human basophils (IC50: 42/340 nmol/L; selectivity ratio ~1:8). HM5023507 attenuated the activation and function of human B and T cells, Th17 differentiation of CD4 T cells in the blood of healthy donors and rheumatoid arthritis patients, and cytokine and IgG production in human T and B cell cocultures, in vitro. Orally dosed HM5023507 attenuated PI3K δ/γ-mediated immune signaling in the rat in a dose-related manner. In addition, HM5023507 inhibited semiestablished collageninduced arthritic inflammation in the rats (ED50 of 0.25mg/kg, p.o. BID or 0.5 mg/kg, QD, AUC: 1422 ng/mL*h), improved histopathology- and micro-computed tomography (μCT)-based indices of joint damage, bone destruction, and attenuated the levels of anticollagen antibody, with an overall anti-inflammatory profile matching that of a TNFα neutralizing antibody. The PI3K δγ inhibitory profile of HM5023507 and its selectivity make it a useful tool to further delineate immunobiology of dual PI3K δγ targeting. [ABSTRACT FROM AUTHOR]

Community‐based pharmacy residency programs, which emerged over 35 years ago, have grown to 218 programs to be the second largest first‐year postgraduate pharmacy residency education and training program in the United States. This paper is intended to provide a history and current status of community‐based pharmacy residency education and training. Multiple major milestones and activities, including funding, advisory panels, training for meeting the Accreditation Standard and other resources have contributed to the evolution of community‐based pharmacy residency programs. Over the years, the community‐based residency program education and training guidelines and standards have changed to focus on the individual. This focus has resulted in the emergence of new practice sites for training such as health‐system community pharmacies and federally‐qualified healthcare centers. The longitudinal learning experiences of the Standard enable residency graduates to function as community‐based pharmacist practitioners (CPPs). CPPs provide leadership and patient care services to meet the needs of patients in the communities that they serve. The next generation of CPPs will lead the advancement and transformation of community‐based pharmacy practice and provide increased access to care and improved patient outcomes. [ABSTRACT FROM AUTHOR]

Population demography is typically assumed to be strongly influenced by climatic factors, particularly with succulent plants and cacti. The saguaro cactus (Carnegiea gigantea) is a long-lived columnar cactus of the Sonoran Desert that experiences episodic recruitment and mortality. Previous studies have attributed long-term changes in saguaro populations to climatic factors, including increased germination and establishment during wet periods and mortality and reduced establishment during droughts and extreme freezes. We used a 48-yr data set of marked individuals at the Desert Laboratory in Tucson, Arizona, to test the hypothesis that local, temporal population trajectories are mediated by topographic heterogeneity that interacts with fluctuating climatic conditions. We tested the influence of local slope and aspect vs. climatic variability on a population of saguaro using >5800 marked individuals that have been measured since 1964. We examined the relationship between demography and climatic variables (drought, precipitation, and extreme temperatures) and found significant differences in growth and survival among aspects and among census periods. Saguaro population growth was higher during wet and cool periods (e.g., 1964–1970), and changes in age structures suggest that topographic differences interact with climatic fluctuations to produce unexpected demographic patterns including large recruitment events during periods of relatively unfavorable climate conditions. Our results highlight the importance of long-term data to detect demographic responses to climate that could not be predicted from short-term studies of plant physiology and population demography. [ABSTRACT FROM AUTHOR]

Phylogenetically informed trait comparisons across entire communities show promise in advancing community ecology. We use this approach to better understand the composition of a community of winter annual plants with multiple decades of monitoring and detailed morphological, phenological and physiological measurements. Previous research on this system revealed a physiological trade‐off among dominant species that accurately predicts population and community dynamics. Here we expanded our investigation to 51 species, representing 96% of individual plants recorded over 30 years, and analysed trait relationships in the context of species abundance and phylogenetic relationships. We found that the functional‐trait trade‐off scales to the entire community, albeit with diminished strength. It is strongest for dominant species and weakens as progressively rarer species are included. The trade‐off has been consistently expressed over three decades of environmental change despite some turnover in the identity of dominant species. [ABSTRACT FROM AUTHOR]

Abstract: Seed size is a functional trait with important fitness consequences that potentially extend throughout the life cycle of plants. Dithyrea californica experiences selection for larger seeds in postgermination stages but it is still uncertain how environmental factors mediate the strength and the direction of natural selection on seed size. Dithyrea californica represents a unique opportunity to investigate selection on seed size in natural conditions due to a persistent seed ring that stays attached to the root throughout the plant’s life. This makes it possible to unearth plants at any stage and measure the size of the seed from which they originated. We conducted a factorial experiment manipulating water availability and intraspecific competition using plants that naturally germinated in the wild. Selection on seed size via survivorship was nil because all individuals survived to reproduce. The strength and the direction of selection on seed size via fecundity depended on water availability and conspecific density. Contrary to our predictions, increasing conspecific density relaxed directional selection favouring larger seeds, but only in the wettest conditions and an increase in water availability strengthened it, but only at low density. A possible explanation of these counter‐intuitive results relies on the observed absence of survival selection and increased plant growth rates under high water and low density. Larger seeds require more resources to construct, and when this cost is taken into account, there is no overall fitness increase with seed size. This nicely follows the life‐history theory predictions for optimal seed size. At the evolutionary equilibrium, if seeds could be larger, per seed fitness would still increase, which is what we observed, but cost‐corrected fitness should be flat. Maternal fitness equals per seed fitness times seed number, so any increase to per seed fitness of making a bigger seed is balanced by the resulting cost to seed number. Our results indicate flat cost‐corrected fitness of seed size as theory predicts. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

Numerous mechanisms may allow species to coexist. We tested for frequency-dependent predation, a mechanism predicted by theory and established as a foraging behavior for many types of animals. Our field test included multiple prey species exposed in situ to multiple predator species and individuals to determine whether the prey species experienced predation patterns that were frequency dependent. The prey were seeds of three species of Sonoran Desert winter annual plants while the predator species were a guild of nocturnal seed foraging heteromyid and murid rodents that co-occur naturally in the same community as the desert annuals at Tumamoc Hill near Tucson. Seeds of one species were much preferred over the other two. Nonetheless, we found the net effect of rodent foraging to be positively frequency dependent (the preference for each species is higher when it is common than when it is uncommon) as has been previously hypothesized. This frequency-dependent predation should function as a species coexistence promoting mechanism in concert with the storage effect that has been previously demonstrated for this system. [ABSTRACT FROM AUTHOR]

The use of technology can enhance workplace efficiency, productivity, and flexibility; yet, technological tools can have negative effects on individuals' cognitive, psychological, and physical health, as well as on organizations (e.g., lowered employee satisfaction, decreased employee commitment). The use of information and communications technologies (ICT) adds to existing work stress. The authors reviewed recent literature to identify ICT trends, define key terms, and gain insights to improve awareness of ICT issues related to career development, health and wellness, and job security. The potential for inquiry as it relates to career exploration, development, and advancement is relevant to counselors and clients in today's workplace. Research is needed to examine the effects of technostress across different industries, to identify workers at greatest risk of adverse effects, to explore the impact on career decision making, to help clients develop personal coping resources, and to determine strategies for career professionals to collaborate with workplace managers. [ABSTRACT FROM AUTHOR]

In variable environments, organisms must have strategies to ensure fitness as conditions change. For plants, germination can time emergence with favourable conditions for later growth and reproduction (predictive germination), spread the risk of unfavourable conditions (bet hedging) or both (integrated strategies). Here we explored the adaptive value of within- and among-year germination timing for 12 species of Sonoran Desert winter annual plants. We parameterised models with long-term demographic data to predict optimal germination fractions and compared them to observed germination. At both temporal scales we found that bet hedging is beneficial and that predicted optimal strategies corresponded well with observed germination. We also found substantial fitness benefits to varying germination timing, suggesting some degree of predictive germination in nature. However, predictive germination was imperfect, calling for some degree of bet hedging. Together, our results suggest that desert winter annuals have integrated strategies combining both predictive plasticity and bet hedging. [ABSTRACT FROM AUTHOR]

Background: Fear of blood draws is a predictor of vasovagal reaction risk among whole blood donors, and this relationship is particularly evident among less experienced donors. This study examines the combined effect of donor fear and total blood draw time on vasovagal reactions.Study Design and Methods: After successfully completing the blood donor health screening, 2730 whole blood donors attending high school drives were asked about their fear of having blood drawn. Donor reports of fear versus no fear were combined with total blood draw time to predict phlebotomist ratings of donor vasovagal reactions.Results: Both fear and draw time were significant predictors of vasovagal reactions, with observed reaction rates of 31.2% for fearful donors whose blood draw lasted 10 minutes or more versus 5.0% for nonfearful donors whose draw lasted less than 6 minutes. Binomial regression analyses revealed that fear remained a significant predictor of reaction rates across all blood draw intervals examined (odds ratio, 2.8-4.1; all p < 0.001) and that these effects were maintained after controlling for donor sex, weight, estimated blood volume, pulse rate, and donation status.Conclusion: This report shows that both fear and blood draw time increase vasovagal reaction rates, and the two are additive. These findings suggest that fearful donors should be the focus of special attention to reduce their distress before donation as well as careful observation throughout the draw. [ABSTRACT FROM AUTHOR]

Early life-cycle events play critical roles in determining the population and community dynamics of plants. The ecology of seeds and their germination patterns can determine range limits, adaptation to environmental variation, species diversity, and community responses to climate change. Understanding the adaptive consequences and environmental filtering of such functional traits will allow us to explain and predict ecological dynamics. Here we quantify key functional aspects of germination physiology and relate them to an existing functional ecology framework to explain long-term population dynamics for 13 species of desert annuals near Tucson, Arizona, USA. Our goal was to assess the extent to which germination functional biology contributes to long-term population processes in nature. Some of the species differences in base, optimum, and maximum temperatures for germination, thermal times to germination, and base water potentials for germination were strongly related to 20-yr mean germination fractions, 25-yr average germination dates, seed size, and long-term demographic variation. Comparisons of germination fraction, survival, and fecundity vs. yearly changes in population size found significant roles for all three factors, although in varying proportions for different species. Relationships between species' germination physiologies and relative germination fractions varied across years, with fast-germinating species being favored in years with warm temperatures during rainfall events in the germination season. Species with low germination fractions and high demographic variance have low integrated water-use efficiency, higher vegetative growth rates, and smaller, slower-germinating seeds. We have identified and quantified a number of functional traits associated with germination biology that play critical roles in ecological population dynamics. [ABSTRACT FROM AUTHOR]

Aims: Understanding the relationship between species and environments is at the heart of ecology and biology. Ranges of species depend strongly on environmental factors, but our limited understanding of relationships between range and trait stability of species across environments hampers our ability to predict their future ranges. Species that occur over a wide range (and thus have wide niche breadth) will have high variation in morpho-physiological traits in response to environmental conditions, thereby permitting stability of performance traits and enabling plants to survive in a range of environments. We hypothesized that species' niche breadth is negatively correlated with the rate of performance trait change along an environmental gradient. Location: Northern China. Methods: We analysed standing biomass and height of 48 species of Asteraceae (Artemisia and its close relatives) collected from 65 sites along an environmental gradient across northern China. Results: In support of our hypothesis, there were significant negative correlations between climatic niche breadth and rate of change in biomass, a performance trait, but not in height, which is both amorphological and a performance trait. Conclusions: These findings have implications for risk assessment of species under climate change and prediction of unknown distributions of species. They also offer a new avenue of research for species distribution models. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity in seed provisioning is a widespread phenomenon in plant populations that is often manifested as environmentally induced maternal effects. Environmental maternal effects can be beneficial if they influence population dynamic functions of seeds in a way that increases fitness, such as escaping from crowding. Using the winter annual plant, Dithyrea californica, we studied the response of seed provisioning to the maternal competitive environment and the associated seed dispersal consequences. We measured the average size of seeds produced by plants experiencing different competitive environments in order to test the hypothesis that mother plants respond to crowding by providing fewer resources to each offspring. We also hypothesized that smaller seeds produced by crowded mothers would benefit from greater dispersal away from their high-density natal habitat. We marked seeds with fluorescent paint while still attached to the mother plant, recorded seed diameter, and followed them for nine months after dispersal, recording the distance they moved from the mother plant. Plants that experienced more competition produced smaller seeds that dispersed farther from their mother plant. Larger seed diameter was previously shown to be associated with greater competitive ability in D. californica. Thus the production of smaller seeds in more competitive environments implies a possible trade-off between competitive ability and dispersal arising from an environmentally driven aspect of phenotype. Fitness consequences of this trade-off in the context of the year-to-year variation in rainfall and density are uncertain. [ABSTRACT FROM AUTHOR]

Background Nonresectable mast cell tumors ( MCT) in dogs remain a therapeutic challenge, and investigation of novel combination therapies is warranted. Intermittent administration of tyrosine kinase inhibitors ( TKI) combined with cytotoxic chemotherapy may effectively chemosensitize canine MCT while decreasing cost and adverse effects associated with either agent administered as monotherapy. Hypothesis/Objectives The primary study objectives were to (1) identify the maximally tolerated dose ( MTD), (2) determine the objective response rate ( ORR) and (3) describe the adverse event profile of pulse-administered toceranib phosphate ( TOC) combined with lomustine. Animals Forty-seven client-owned dogs with measurable MCT. Methods Toceranib phosphate was given PO on days 1, 3 and 5 of a 21-day cycle at a target dosage of 2.75 mg/kg. Lomustine was given PO on day 3 of each cycle at a starting dosage of 50 mg/m2. All dogs were concurrently treated with diphenhydramine, omeprazole, and prednisone. Results The MTD of lomustine was established at 50 mg/m2 when combined with pulse-administered TOC; the dose-limiting toxicity was neutropenia. Forty-one dogs treated at the MTD were evaluable for outcome assessment. The ORR was 46% (4 complete response, 15 partial response) and the overall median progression-free survival ( PFS) was 53 days (1 to >752 days). On multivariate analysis, variables significantly associated with improved PFS included response to treatment, absence of metastasis, and no previous chemotherapy. Conclusions and clinical importance Combined treatment with pulse-administered TOC and lomustine generally is well tolerated and may be a reasonable treatment option for dogs with unresectable or metastatic MCT. [ABSTRACT FROM AUTHOR]

Under stressful circumstances, seed size has important consequences for germination, survival, and reproductive success; all of these are important components of plant fitness. This study investigates the relationship between seed size and fitness in the Sonoran Desert winter annual Dithyrea californica. This species represents a unique opportunity to study natural selection on seed size in the wild due to a serendipitous detail of its life history: the seed coat remains attached and unchanged to the root throughout its life. It is thus possible to excavate the root and measure the seed size that originated each plant. We measured the relationship between seed size and germination by comparing seed sizes of germinated and dormant seeds in the field over four consecutive years. We also measured the effect of seed size on survival and reproductive success using data from censuses of plant mortality and fecundity of survivors, relating survival and fecundity to the size of their initial seed size, and the number of conspecific neighbors. Larger seeds had a higher probability of germination than smaller seeds. Plants originating from larger seeds had higher survival rates and higher fecundity than plants originating from smaller seeds. The amount of precipitation had a beneficial effect on plant fecundity and influenced seed-size survival selection. Plant competition decreased plant fecundity but not survival, creating a detrimental environment for plants only to grow and reproduce. This is the first study to show empirical evidence of seed-size selection throughout the whole life cycle in a natural setting. Further, maternal provisioning has benefits that persist into adulthood, and environmental interactions are important in determining survival and fecundity. [ABSTRACT FROM AUTHOR]

CHARMM-GUI Membrane Builder, , is a web-based user interface designed to interactively build all-atom protein/membrane or membrane-only systems for molecular dynamics simulations through an automated optimized process. In this work, we describe the new features and major improvements in Membrane Builder that allow users to robustly build realistic biological membrane systems, including (1) addition of new lipid types, such as phosphoinositides, cardiolipin (CL), sphingolipids, bacterial lipids, and ergosterol, yielding more than 180 lipid types, (2) enhanced building procedure for lipid packing around protein, (3) reliable algorithm to detect lipid tail penetration to ring structures and protein surface, (4) distance-based algorithm for faster initial ion displacement, (5) CHARMM inputs for P21 image transformation, and (6) NAMD equilibration and production inputs. The robustness of these new features is illustrated by building and simulating a membrane model of the polar and septal regions of E. coli membrane, which contains five lipid types: CL lipids with two types of acyl chains and phosphatidylethanolamine lipids with three types of acyl chains. It is our hope that CHARMM-GUI Membrane Builder becomes a useful tool for simulation studies to better understand the structure and dynamics of proteins and lipids in realistic biological membrane environments. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Daily time step data from National Resources Conservation Service snow telemetry (SNOTEL) stations were used to estimate components of the snowmelt-dominated hydrograph for three small watersheds in Colorado and Wyoming. Thirty-three years of SNOTEL data was paired with streamflow data to estimate the annual run-off volume ( Q100) and peak streamflow ( Qpeak), as well as the timing of 20, 50, and 80% ( tQ20, tQ50, and tQ80) of the annual streamflow. Multivariate regression models were derived from snow water equivalent (SWE) data for one basin (Joe Wright Creek), and the model components were then retained and applied to the other two watersheds. The basin-specific coefficients developed for the Joe Wright model were also applied to the other two basins to evaluate direct transferability. Peak SWE, date of peak SWE, and number of consecutive days with snow on the ground up to the date of peak SWE had the strongest correlation to streamflow and formed the basis of the models. The optimal model configuration performed well for the tQ20, tQ50, and Q100, with poorer performance for Qpeak and tQ80. Applying the Joe Wright Creek coefficients directly to the other watersheds yielded reasonable results. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Seed dormancy, by controlling the timing of germination, can strongly affect plant survival. The kind of seed dormancy, therefore, can influence both population and species-level processes such as colonization, adaptation, speciation, and extinction., We used a dataset comprising over 14 000 taxa in 318 families across the seed plants to test hypotheses on the evolution of different kinds of seed dormancy and their association with lineage diversification., We found morphophysiological dormancy to be the most likely ancestral state of seed plants, suggesting that physiologically regulated dormancy in response to environmental cues was present at the origin of seed plants. Additionally, we found that physiological dormancy (PD), once disassociated from morphological dormancy, acted as an 'evolutionary hub' from which other dormancy classes evolved, and that it was associated with higher rates of lineage diversification via higher speciation rates., The environmental sensitivity provided by dormancy in general, and by PD in particular, appears to be a key trait in the diversification of seed plants. [ABSTRACT FROM AUTHOR]

Background Helicobacter pylori colonization of the gastric epithelium induces interleukin-8 ( IL-8) production and inflammation leading to host cell damage. We searched for gastric-derived Lactobacillus with the ability to suppress H. pylori-induced inflammation. Materials and methods Conditioned media from gastric-derived Lactobacillus spp. were tested for the ability to suppress H. pylori-induced IL-8 production in AGS gastric epithelial cells. IL-8 protein and m RNA levels were measured by ELISA and q PCR, respectively. The changes on host cell signaling pathway were analyzed by Western blotting and the anti-inflammatory effect was tested in a Sprague- Dawley rat model. Results Conditioned media from L. salivarius B101, L. rhamnosus B103, and L. plantarum XB7 suppressed IL-8 production and IL-8 m RNA expression in H. pylori-induced AGS cells without inhibiting H. pylori growth. Conditioned media from LS- B101, LR- B103, and LP- XB7 suppressed the activation of NF-κ B in AGS cells, while strain LP- XB7 also suppressed c-Jun activation. The anti-inflammatory effect of LP- XB7 was further assessed in vivo using a H. pylori-infected Sprague- Dawley rat model. Strain LP-XB7 contributed to a delay in the detection and colonization of H. pylori in rat stomachs, attenuated gastric inflammation, and ameliorated gastric histopathology. Additionally, the administration of LP- XB7 correlated with the suppression of TNF-α and CINC-1 in sera, and suppression of CINC-1 in the gastric mucosa of H. pylori-infected rats. Conclusions These results suggest that L. plantarum XB7 produces secreted factors capable of modulating inflammation during H. pylori infection, and this probiotic Lactobacillus strain shows promise as an adjunctive therapy for treating H. pylori-associated disease. [ABSTRACT FROM AUTHOR]

Background We previously demonstrated that fear of having blood drawn is one of the strongest known predictors of vasovagal reactions among high school blood donors. This report examines the combined effects of donor fear and experience of vasovagal reactions on repeat donation attempts among high school blood donors. Study Design and Methods Immediately after completing the blood donor health screening, 1715 high school students were asked about their fear of having blood drawn. The donor record was then used to collect information regarding their experience of vasovagal reactions at the time of donation as well as their subsequent donation attempts within the following year. Results Fear of having blood drawn and the experience of a vasovagal reaction each contributed to donor attrition, with only 33.2% of fearful donors who experienced a vasovagal reaction returning in the following year compared to 56.7% of nonfearful nonreactors. Path analyses demonstrated that fear has an indirect effect (through vasovagal reactions) on repeat donations among first-time donors and both direct and indirect effects on repeat donation attempts among experienced donors. Conclusion Among high school blood donors, fear of having blood drawn has both a direct negative effect on donor retention and an indirect negative effect by increasing the risk of vasovagal reactions. Accordingly, targeted efforts to reduce donor fear may be particularly efficient in promoting long-term donor loyalty among our youngest donors. [ABSTRACT FROM AUTHOR]

In bet hedging, organisms sacrifice short-term success to reduce the long-term variance in success. Delayed germination is the classic example of bet hedging, in which a fraction of seeds remain dormant as a hedge against the risk of complete reproductive failure. Here, we investigate the adaptive nature of delayed germination as a bet hedging strategy using long-term demographic data on Sonoran Desert winter annual plants. Using stochastic population models, we estimate fitness as a function of delayed germination and identify evolutionarily stable strategies for 12 abundant species in the community. Results indicate that delayed germination meets the criteria as a bet hedging strategy for all species. Density-dependent models, but not density-independent ones, predicted optimal germination strategies that correspond remarkably well with observed patterns. By incorporating naturally occurring variation in seed and seedling dynamics, our results present a rigorous test of bet hedging theory within the relevant environmental context. [ABSTRACT FROM AUTHOR]

* Premise of the study: A functional approach to investigating competitive interactions can provide a mechanistic understanding of processes driving population dynamics, community assembly, and the maintenance of biodiversity. In Sonoran Desert annual plants, a trade-off between relative growth rate (RGR) and water-use efficiency (WUE) contributes to species differences in population dynamics that promote long-term coexistence. Traits underlying this trade-off explain variation in demographic responses to precipitation as well as life history and phenological patterns. Here, we ask how these traits mediate competitive interactions. * Methods: We conducted competition trials for three species occupying different positions along the RGR-WUE trade-off axis and compared the effects of competition at high and low soil moisture. We compared competitive effect (ability to suppress neighbors) and competitive response (ability to withstand competition from neighbors) among species. * Key results: The RGR-WUE trade-off predicted shifts in competitive responses at different soil moistures. The high-RGR species was more resistant to competition in high water conditions, while the opposite was true for the high-WUE species. The intermediate RGR species tended to have the strongest impact on all neighbors, so competitive effects did not scale directly with differences in RGR and WUE among competitors. * Conclusions: Our results reveal mechanisms underlying long-term variation in fitness: high-RGR species perform better in years with large, frequent rain events and can better withstand competition under wetter conditions. The opposite is true for high-WUE species. Such resource-dependent responses strongly influence community dynamics and can promote coexistence in variable environments. [ABSTRACT FROM AUTHOR]

Granulocytes play a key role in innate immunity and the most common functional assays are phagocytosis and oxidative burst. The purpose of this technical note is to use image-based flow cytometry to divide activated granulocytes into unique subsets based on their degree of phagocytosis and oxidative burst in response to different experimental incubations. Prior to the experiments, all reagents were titered to determine the lowest dose that resulted in an acceptable signal to noise ratio. Heparinized, whole blood (100 µl) was mixed with one of two bioparticles ( E. coli and S. aureus) and DHE (10 µg/ml) and incubated for 5, 10, 20, 40, 60, 80, 100, 120, and 140 min in a 37°C water bath. An additional tube kept on ice was used as a negative control. All subsequent processing steps were completed on ice in the dark to minimize additional activation of cells. After the 37°C incubation, N-ethylmaleimide (15 m M) was added to halt phagocytosis, preventing the uptake of additional microparticles. Suspensions were labeled with CD66b-APC and CD45-APCeFluor780 for 60 min and a fix/lyse solution was added. Prior to acquisition, 7AAD was added to stain nuclear DNA. A minimum of 5,000 granulocyte (CD66b+) events were acquired using a Millipore-Amnis FlowSight equipped with blue (488 nm, 60 mW), red (642 nm, 100 mW), and side scatter (785 nm, 12 mW) lasers. Samples were compensated and analyzed using Amnis IDEAS software (v.5.0.983.0). Image-based analysis allowed us to divide activated granulocytes into three distinct subsets, whose relative abundance changed as a function of both bioparticle type and incubation length. The method described in this technical note represents a potential novel adaptation to common methods of assessing granulocyte function. More research is needed to test and validate our image-based method in clinical conditions that impair granulocyte function. © 2013 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

Global change requires plant ecologists to predict future states of biological diversity to aid the management of natural communities, thus introducing a number of significant challenges. One major challenge is considering how the many interacting features of biological systems, including ecophysiological processes, plant fife histories, and species interactions, relate to performance in the face of a changing envffomnent. We have employed a functional trait approach to understand the individual, population, and community dynamics of a raodel system of Sonoran Desert winter annual plants. We have used a comprehensive approach that connects physiological ecology and comparative biology to population and community dynamics, while emphasizing both ecological and evolutionary processes. This approach has led to a fairly robust understanding of past and contemporary dynamics in response to changes in climate. In this community, there is striking variation in physiological and demographic responses to both precipitation and temperature that is described by a trade-off between water-use efficiency (WUE) and relative growth rate (RGR). This community-wide trade-off predicts both the demographic and life history variation that contribute to species coexistence. Our framework has provided a mechanistic explanation to the recent warming, drying, and climate variability that has driven a surprising shift in these communities: cold-adapted species with more buffered population dynamics have increased in relative abundance. These types of comprehensive approaches that acknowledge the hierarchical nature of biology may be especially useful in aiding prediction. The emerging, novel and nonstationary climate constrains ore use of simplistic statistical representations of past plant behavior in predicting the future, without understanding the mechanistic basis of change. [ABSTRACT FROM AUTHOR]

Key points Mitochondrial inner membrane potential (ΔΨm) collapse during myocardial ischaemia is one of the key events determining the physiological consequences of ischaemic attack in terms of post-ischaemic arrhythmias and cell survival., Timing and pattern of ΔΨm collapse during ischaemia remain controversial, in part due to difficulties in interpreting the fluorescence of potentiometric cationic probes commonly used for assessment of ΔΨm in cellular and multicellular experimental models., This manuscript presents a new method for monitoring ΔΨm in whole hearts based on the regular arrangement of mitochondria in cardiac myocytes, thus permitting detection of ΔΨm collapse using spectral analysis of fluorescence., The proposed method will help to ascertain the role of mitochondrial function in acute cardiovascular conditions, such as acute myocardial infarction or sudden cardiac arrest., Abstract Timing and pattern of mitochondrial potential (ΔΨm) depolarization during no-flow ischaemia-reperfusion (I-R) remain controversial, at least in part due to difficulties in interpreting the changes in the fluorescence of ΔΨm-sensitive dyes such as TMRM. The objective of this study was to develop a new approach for interpreting confocal TMRM signals during I-R based on spatial periodicity of mitochondrial packaging in ventricular cardiomyocytes. TMRM fluorescence ( FTMRM) was recorded from Langendorff-perfused rabbit hearts immobilized with blebbistatin using either a confocal microscope or an optical mapping system. The hearts were studied under normal conditions, during mitochondrial uncoupling using the protonophore FCCP, and during I-R. Confocal images of FTMRM were subjected to spatial Fourier transform which revealed distinct peaks at a spatial frequency of ∼2 μm−1. The area under the peak (MPA) progressively decreased upon application of increasing concentrations of FCCP (0.3-20 μ m), becoming undetectable at 5-20 μ m FCCP. During ischaemia, a dramatic decrease in MPA, reaching the low/undetectable level comparable to that induced by 5-20 μ m FCCP, was observed between 27 and 69 min of ischaemia. Upon reperfusion, a heterogeneous MPA recovery was observed, but not a de novo MPA decrease. Both confocal and wide-field imaging registered a consistent decrease in spatially averaged FTMRM in the presence of 5 μ m FCCP, but no consistent change in this parameter during I-R. We conclude that MPA derived from confocal images provides a sensitive and specific indicator of significant mitochondrial depolarization or recovery during I-R. In contrast, spatially averaged FTMRM is not a reliable indicator of ΔΨm changes during I-R. [ABSTRACT FROM AUTHOR]

All-atom simulations are carried out on ErbB1/B2 and EphA1 transmembrane helix dimers in lipid bilayers starting from their solution/DMPC bicelle NMR structures. Over the course of microsecond trajectories, the structures remain in close proximity to the initial configuration and satisfy the majority of experimental tertiary contact restraints. These results further validate CHARMM protein/lipid force fields and simulation protocols on Anton. Separately, dimer conformations are generated using replica exchange in conjunction with an implicit solvent and lipid representation. The implicit model requires further improvement, and this study investigates whether lengthy all-atom molecular dynamics simulations can alleviate the shortcomings of the initial conditions. The simulations correct many of the deficiencies. For example, excessive helix twisting is eliminated over a period of hundreds of nanoseconds. The helix tilt, crossing angles, and dimer contacts approximate those of the NMR-derived structure, although the detailed contact surface remains off-set for one of two helices in both systems. Hence, even microsecond simulations are not long enough for extensive helix rotations. The alternate structures can be rationalized with reference to interaction motifs and may represent still sought after receptor states that are important in ErbB1/B2 and EphA1 signaling. Proteins 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

BACKGROUND: We previously demonstrated in a group of mostly experienced blood donors that fear of blood draws was a significant predictor of vasovagal reactions. Importantly, being asked about one's fear immediately before donation did not increase reaction rates. This study further evaluates the relationship between fear and reactions among high school blood donors, who are known to be at a relatively greater risk for vasovagal reactions. STUDY DESIGN AND METHODS: Immediately after completing the blood donor health screening, 17- and 18-year-old high school students were asked about their fear of having blood drawn. Based on a random selection, the fear question was administered in approximately half of the schools, resulting in a final sample of 1715 donors who did and 1692 donors who did not answer the fear question. RESULTS: Fear was a significant predictor of donor reactions and remained a significant independent predictor (along with estimated blood volume and donor sex) in a logistic regression analysis. There was no difference in the proportion of reactions observed between those who did and did not answer the predonation fear question. CONCLUSION: Consistent with previous evidence in older and more experienced blood donors, these findings indicate that assessing fear of blood draws may help to identify those who are most likely to experience vasovagal reactions among young donors without increasing the frequency of such reactions. [ABSTRACT FROM AUTHOR]

How species respond to environmental variation can have important consequences for population and community dynamics. Temperature, in particular, is one source of variation expected to strongly influence plant performance. Here, we compared photosynthetic responses to temperature across a guild of winter annual plants. Previous work in this system identified a trade-off between relative growth rate (RGR) and water-use efficiency (WUE) that predicts species differences in population dynamics over time, which then contribute to long-term species coexistence. Interestingly, species with high WUE invest in photosynthetic processes that appear to maximize carbon assimilation, while high-RGR species appear to maximize carbon gain by increasing leaf area for photosynthesis. In high-WUE species, higher rates of carbon acquisition were associated with increased investment into light-driven electron transport (Jmax). We tested whether such allocation allows these plants to have greater photosynthetic performance at lower temperatures by comparing the temperature sensitivity of photosynthesis across species in the community. Six species were grown in buried pots in the field, allowing them to experience natural changes in seasonal temperature. Plants were taken from the field and placed in growth chambers where photosynthetic performance was measured following short-term exposure to a wide range of temperatures. These measurements were repeated throughout the season. Our results suggest that high-WUE species are more efficient at processing incoming light, as measured by chlorophyll fluorescence, and exhibit higher net photosynthetic rates (/lnet) than high-RGR species, and these advantages are greatest at low temperatures. Sampling date differentially affected fluorescence across species, while species had similar seasonal changes in Ancl. Our results suggest that species-specific responses to temperature contribute to the WUE-RGR trade-off that has been shown to promote coexistence in this community. These differential responses to environmental conditions can have important effects on fitness, population dynamics, and community structure. [ABSTRACT FROM AUTHOR]

Common methods for assaying acyl-CoA:diacylglycerol acyltransferase (DGAT) enzymatic activity rely upon radiolabeled substrates or product assay. We developed a novel assay that directly quantifies endogenous DGAT activity through the use of a fluorescently labeled substrate. We performed this assay with microsomal protein, 2-(6-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)hexanoyl-1-hexadecanoyl- sn-glycero-3-diacylglycerol (NBD-DAG), and oleoyl-CoA substrates. DGAT activity was analyzed in three species of algae as well as rat liver. The protocol proved to be sensitive and reliable. This assay may be used to facilitate research in the areas of biodiesel, oilseed crops, and triacylglycerol-related human pathologies. [ABSTRACT FROM AUTHOR]

Common methods for assaying acyl-CoA:diacylglycerol acyltransferase (DGAT) enzymatic activity rely upon radiolabeled substrates or product assay. We developed a novel assay that directly quantifies endogenous DGAT activity through the use of a fluorescently labeled substrate. We performed this assay with microsomal protein, 2-(6-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)hexanoyl-1-hexadecanoyl- sn-glycero-3-diacylglycerol (NBD-DAG), and oleoyl-CoA substrates. DGAT activity was analyzed in three species of algae as well as rat liver. The protocol proved to be sensitive and reliable. This assay may be used to facilitate research in the areas of biodiesel, oilseed crops, and triacylglycerol-related human pathologies. [ABSTRACT FROM AUTHOR]

Beneficial microbes and probiotics show promise for the treatment of pediatric gastrointestinal diseases. However, basic mechanisms of probiosis are not well understood, and most investigations have been performed in germ-free or microbiome-depleted animals. We sought to functionally characterize probiotichost interactions in the context of normal early development. Outbred CD1 neonatal mice were orally gavaged with one of two strains of human-derived Lactobacillus reuteri or an equal volume of vehicle. Transcriptome analysis was performed on enterocyte RNA isolated by laser-capture microdissection. Enterocyte migration and proliferation were assessed by labeling cells with 5-bromo-2-deoxyuridine, and fecal microbial community composition was determined by 16S metagenomic sequencing. Probiotic ingestion altered gene expression in multiple canonical pathways involving cell motility. L. reuteri strain DSM 17938 dramatically increased enterocyte migration (3-fold), proliferation (34%), and crypt height (29%) compared to vehicle-treated mice, whereas strain ATCC PTA 6475 increased cell migration (2-fold) without affecting crypt proliferative activity. In addition, both probiotic strains increased the phylogenetic diversity and evenness between taxa of the fecal microbiome 24 h after a single probiotic gavage. These experiments identify two targets of probiosis in early development, the intestinal epithelium and the gut microbiome, and suggest novel mechanisms for probiotic strain-specific effects. [ABSTRACT FROM AUTHOR]

Bursera is one of the most diverse and abundant groups of trees and shrubs of the Mexican tropical dry forests. Its interaction with its specialist herbivores in the chrysomelid genus Blepharida, is one of the best-studied coevolutionary systems. Prior studies based on molecular phylogenies concluded that Bursera is a monophyletic genus. Recently, however, other molecular analyses have suggested that the genus might be paraphyletic, with the closely related Commiphora, nested within Bursera. If this is correct, then interpretations of coevolution results would have to be revised. Whether Bursera is or is not monophyletic also has implications for the age of Burseraceae, since previous dates were based on calibrations using Bursera fossils assuming that Bursera was paraphyletic. We performed a phylogenetic analysis of 76 species and varieties of Bursera, 51 species of Commiphora, and 13 outgroups using nuclear DNA data. We also reconstructed a phylogeny of the Burseraceae using 59 members of the family, 9 outgroups and nuclear and chloroplast sequence data. These analyses strongly confirm previous conclusions that this genus is monophyletic. New calculations of the age of Burseraceae date the beginning of its diversification to at least 93 million years ago. [ABSTRACT FROM AUTHOR]