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Supporting teachers' attention and responsiveness to the substance of student thinking is increasingly emphasized across disciplines. Yet studies demonstrate how such responsiveness, in practice, is highly contextualized and often fleeting. This study conceptualizes and examines what functioned as "resources for responsiveness" within and across nine sustained cases of responsiveness in three science teachers' inquiry-oriented classrooms. Analyses demonstrated how a diverse range of personal, social, and material/structural resources facilitated teachers' responsiveness, with some commonalities but also much variation across teachers. These findings contribute to the field's understanding of what may support teachers' attention and responsiveness to student thinking and suggest the importance of (a) responsiveness in the design and facilitation of professional learning and (b) increased attention to teachers' affect. [ABSTRACT FROM AUTHOR]

Young children tend to behave more generously when their actions are identified than when they are anonymous, yet we know little about the cognitive foundations required for anonymity to impact generosity. In three studies we examined Canadian children's understanding of anonymity and its impact on sharing in anonymous and identified contexts. Study 1 assessed whether 3- and 5-year-old children (N = 100, 51 female) understood anonymous and identified sharing, and whether age-related changes in their understanding corresponded to sharing behavior. We found that understanding of anonymity improved with age, but anonymity did not influence sharing. Study 2 assessed 5-year-old children's (N = 60, 30 female) judgments about how others would share in these contexts and their preferences for receiving donations from identified or anonymous donors. We found that children preferred to receive from identified donors and believed that identified donors were more generous. Study 3 assessed whether 5-year-old children (N = 60, 30 female) preferred to share as anonymous or identified donors themselves, and whether their choice influenced sharing behavior. We found that while participants preferred to share as identified donors, this choice did not influence sharing. Overall, our findings suggest that although 5-year-old Canadian children have a robust understanding of the implications of anonymous and identified sharing, this understanding is not sufficient to motivate increased generosity. [ABSTRACT FROM AUTHOR]

Adolescents' self-control develops in the context of mental health and family functioning, but it is unclear how the interplay of self-control, mental health, and family functioning unfolds across time within individuals. Separating within-person from between-person effects, random-intercept cross-lagged panel models were applied to adolescents (from ages 11 to 26) from a Dutch cohort (n = 2228, 51% female). Adolescents with low self-control were likely to have mental health problems and poorly functioning families. Although within-person changes in the study variables were not meaningfully associated in a reciprocal manner, changes in self-control and mental health were concurrently associated. This suggests that besides stable connections between self-control, mental health, and family functioning in adolescence and young adulthood, changes in self-control and mental health are developmentally linked as well. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has had devastating global and national impacts including major loss of life, economic downturns, and ongoing impairments to mental and physical health. Conducting health research has remained a priority and has helped mitigate some of the COVID-19 devastation; however, challenges to research have arisen due to COVID-19 prevention strategies and changing community priorities for research. The purpose of this article is to focus on a critical piece of the health research process with American Indian and Alaska Native (AI/AN) communities and the AI/AN health research workforce. Throughout this editorial, we provide challenges faced while conducting research with AI/AN communities during the COVID-19 pandemic including changes to research processes and ongoing research studies, taking on multiple roles in academic spaces, and mourning for continuous community loss while continuing to conduct research that may benefit AI/AN communities. Using a strengths-based lens, we also provide examples of flexibility, adaptation, and resilience in the face of the ongoing COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Introduction: American Indian (AI) people have protective factors embedded in cultural teachings that buffer against high-risk behaviors. This study applies a qualitative, grounded theory approach to identify cultural assets for a Diné (Navajo) mother-daughter intervention aimed at preventing substance abuse and teen pregnancy. Method: Focus groups and in-depth interviews were conducted with 28 AI females' ages 8 years and older from the Navajo Nation. Results: Key themes were (a) preserving the Diné way of life, (b) cultural assets related to being a healthy Diné woman, (c) matrilineal networks as a source of strength/pride, (d) historical trauma as a source of resilience, (e) male influences as protective health factors, (f) Western education as a measure of success, and (g) integrating different belief systems. Discussion: Study findings may be applied as foundational elements for culturally grounded AI substance abuse and teen pregnancy prevention strategies, as well as culturally safe nursing practice. [ABSTRACT FROM AUTHOR]

Objective Method Results Conclusions This study tested two opposing hypotheses on the continuity of psychopathology throughout adolescence and young adulthood; differentiation versus dynamic mutualism. Differentiation predicts that co-occurrence decreases, while dynamic mutualism predicts that co-occurrence increases due to causal interactions amongst mental health problems.Using data from the Dutch TRacking Adolescents’ Individual Lives Survey (n = 2228, 51% female), we studied the development of self-reported internalizing, externalizing, and attention problems at ages 11 to 26 across six waves. Random-intercept cross-lagged panel modeling was employed to distinguish within-person development from stable between-person processes.Large stable between-person associations indicated that adolescents with internalizing problems tended to have both externalizing and attention problems as well. On a within-person level, mental health problems showed partial stability and strong cross-sectional co-occurrence. Within-wave associations of internalizing with externalizing or attention problems decreased between age 11 and 16 years, after which they increased again. Little heterotypic continuity was found: age 11 externalizing predicted age 13 attention, which in turn predicted age 16 externalizing problems, and internalizing predicted externalizing problems across ages 22 to 26. Findings were similar for males and females.Our findings suggest co-occurrence decreases during early and middle adolescence, supporting differentiation. While co-occurrence increased again into young adulthood, this could not be labeled as dynamic mutualism because little evidence for heterotypic continuity was found in this phase of life. The strong stable links between internalizing, externalizing, and attention problems stress the importance of targeting these mental health problems and their shared risk factors together. [ABSTRACT FROM AUTHOR]

The aim of this study was to test a longitudinal, transactional model that describes how social withdrawal and friendship development are interrelated in late adolescence, and to investigate if post‐secondary transitions are catalysts of change for highly withdrawn adolescents' friendships. Unilateral friendship data of 1,019 adolescents (61.3% female, 91% Dutch‐origin) from the Tracking Adolescents' Individual Lives Survey (TRAILS) cohort were collected five times from ages 17 to 18 years. Social withdrawal was assessed at 16 and 19 years. The transactional model was tested within a Structural Equation Modeling framework, with intercepts and slopes of friendship quantity, quality, and stability as mediators and residential transitions, education transitions, and sex as moderators. The results confirmed the presence of a transactional relation between withdrawal and friendship quality. Whereas higher age 16 withdrawal predicted having fewer, lower‐quality, and less‐stable friendships, only having lower‐quality friendships, in turn, predicted higher age 19 withdrawal, especially in girls. Residential transitions were catalysts of change for highly withdrawn youth's number of friends: higher withdrawal predicted a moderate increase in number of friends for adolescents who relocated, and no change for those who made an educational transition or did not transition. Taken together, these results indicate that the quality of friendships—over and above number of friends and the stability of those friendships—is particularly important for entrenching or diminishing withdrawal in late adolescence, and that relocating provides an opportunity for withdrawn late adolescents to expand their friendship networks. [ABSTRACT FROM AUTHOR]

Background: Two series of benzimidazole based thio-oxadiazole and thio-thiadiazole analogues were designed and synthesised as novel antimicrobial drugs through inhibition of phenylalanyl-tRNA synthetase (PheRS), which is a promising antimicrobial target. Compounds were designed to mimic the structural features of phenylalanyl adenylate (Phe-AMP) the PheRS natural substrate. Methods: A 3D conformational alignment for the designed compounds and the PheRS natural substrate revealed a high level of conformational similarity, and a molecular docking study indicated the ability of the designed compounds to occupy both Phe-AMP binding pockets. A molecular dynamics (MD) simulation comparative study was performed to understand the binding interactions with PheRS from different bacterial microorganisms. The synthetic pathway of the designed compounds proceeded in five steps starting from benzimidazole. The fourteen synthesised compounds 5a-d, 6a-c, 8a-d and 9a-c were purified, fully characterised and obtained in high yield. Results: In vitro antimicrobial evaluation against five bacterial strains showed a moderate activity of compound 8b with MIC value of 32 μg/mL against S. aureus, while all the synthesised compounds showed weak activity against both E. faecalis and P. aeruginosa (MIC 128 μg/mL). Conclusion: Compound 8b provides a lead compound for further structural development to obtain high affinity PheRS inhibitors. [ABSTRACT FROM AUTHOR]

Background: The inclusion of protective factors ("assets") are increasingly supported in developing culturally grounded interventions for American Indian (AI) populations. This study sought to explore AI women's cultural assets, perspectives, and teachings to inform the development of a culturally grounded, intergenerational intervention to prevent substance abuse and teenage pregnancy among AI females.Methods: Adult self-identified AI women (N = 201) who reside on the Navajo Nation completed a cross-sectional survey between May and October 2018. The 21-question survey explored health communication around the transition to womanhood, cultural assets, perceptions of mother-daughter reproductive health communication, and intervention health topics. Univariate descriptive analyses, chi squared, and fisher's exact tests were conducted.Results: Respondents ranged in age from 18 to 82 years, with a mean age of 44 ± 15.5 years. Women self-identified as mothers (95; 48%), aunts (59; 30%), older sisters (55; 28%), grandmothers (37; 19%), and/or all of the aforementioned (50; 25%). 66% (N = 95) of women admired their mother/grandmother most during puberty; 29% (N = 58) of women were 10-11 years old when someone first spoke to them about menarche; and 86% (N=172) felt their culture was a source of strength. 70% (N = 139) would have liked to learn more about reproductive health when they were a teenager; 67% (N = 134) felt Diné mothers are able to provide reproductive health education; 51% (N = 101) reported having a rite of passage event, with younger women desiring an event significantly more than older women. Responses also indicate a disruption of cultural practices due to government assimilation policies, as well as the support of male relatives during puberty.Conclusions: Results informed intervention content and delivery, including target age group, expanded caregiver eligibility criteria, lesson delivery structure and format, and protective cultural teachings. Other implications include the development of a complementary fatherhood and/or family-based intervention to prevent Native girls' substance use and teen pregnancy. [ABSTRACT FROM AUTHOR]

Involvement in romantic relationships is a salient developmental task in late adolescence and early adulthood, and deviations from normative romantic development are linked to adverse outcomes. This study investigated to what extent social withdrawal contributed to deviations from normative romantic development, and vice versa, and the interplay between withdrawal and couples' relationship perceptions. The sample included 1710 young adults (55–61% female) from the Tracking Adolescents' Individual Lives Survey cohort and their romantic partners. Data were collected across 4 waves, covering romantic relationships from ages 17 to 29 years. The results showed that higher withdrawal predicted a higher likelihood of romantic non-involvement by adulthood, consistently being single at subsequent waves, and entering one's first relationship when older. Withdrawal moderately decreased when youth entered their first relationship. Male's withdrawal in particular affected romantic relationship qualities and dynamics. These results provide new insights into the developmental sequelae of withdrawn young adults' romantic relationship development. [ABSTRACT FROM AUTHOR]

Social withdrawal and social anxiety are believed to have a bidirectional influence on one another, but it is unknown if their relationship is bidirectional, especially within person, and if peer experiences influence this relationship. We investigated temporal sequencing and the strength of effects between social withdrawal and social anxiety, and the roles of peer victimization and acceptance in the pathways. Participants were 2,772 adolescents from the population-based and clinically referred cohorts of the Tracking Adolescents' Individual Lives Survey. Self- and parent-reported withdrawal, and self-reported social anxiety, peer victimization, and perceived peer acceptance were assessed at 11, 13, and 16 years. Random-intercept cross-lagged panel models were used to investigate within-person associations between these variables. There was no feedback loop between withdrawal and social anxiety. Social withdrawal did not predict social anxiety at any age. Social anxiety at 11 years predicted increased self-reported withdrawal at 13 years. Negative peer experiences predicted increased self- and parent-reported withdrawal at 13 years and increased parent-reported withdrawal at 16 years. In turn, self-reported withdrawal at 13 years predicted negative peer experiences at 16 years. In conclusion, adolescents became more withdrawn when they became more socially anxious or experienced greater peer problems, and increasing withdrawal predicted greater victimization and lower acceptance. [ABSTRACT FROM AUTHOR]

The extremely invasive Old World Climbing Fern, Lygodium microphyllum, has invaded New World tropical and subtropical habitats. Lygodium microphyllum has indeterminate twining leaves that grow up on and shade out host shrubs and trees, their epiphytes, and the understory. This invasive plant threatens numerous native habitats in Florida USA and the Caribbean, including internationally valued conservation lands such as Everglades National Park. Fire, which can reduce or stimulate growth and/or reproduction in different plant species, is one intervention used to manage L. microphyllum, but the effects of burning on this species' growth are unknown. We experimentally burned greenhouse-grown plants, then monitored their growth in response to burning for 18 months. We also clipped a subset of the greenhouse plants to determine whether fire effects were explained by aboveground biomass removal. In our experiment, fire either killed or reduced the regrowth of L. microphyllum plants. Burning killed 25% of the burned plants and slowed growth of the remaining burned plants for up to 18 months post-burn. Size had a significant effect on plant mortality: smaller burned plants had greater mortality than larger plants. Mechanically removing the aboveground biomass (leaves) by clipping did not kill any plants but reduced their growth as compared to controls in the first six months after treatment. Clipped plants, however, had substantially recovered after 12 months. Burned plants were more sensitive to drought than clipped or control plants. The results show that burning does more than remove biomass, compromising the root system and perhaps damaging the hydraulic support system, similar to the latent mortality effects of fire on forest trees. We discuss how fire could affect invasion by this species, incorporating fire effects on spore viability and dispersal, as well as on subsequent plant regrowth. These results show that fire is a useful management tool for L. microphyllum invasions that both kills plants and reduces plant regrowth for up to 18 months. [ABSTRACT FROM AUTHOR]

Key points: The ability of contracting skeletal muscle to attenuate sympathetic vasoconstriction (functional sympatholysis) is critical for maintaining blood flow during exercise‐mediated sympathoexcitation.Functional sympatholysis and endothelial function are impaired with ageing, resulting in compromised blood flow and oxygen delivery to contracting skeletal muscle during exercise.In the present study, intra‐arterial infusion of ACh or ATP to augment endothelium‐dependent signalling during exercise attenuated α1‐adrenergic vasoconstriction in the contracting muscle of older adults.The vascular signalling mechanisms capable of functional sympatholysis are preserved in healthy ageing, and thus the age‐related impairment in functional sympatholysis probably results from the loss of a functional signal (e.g. plasma [ATP]) as opposed to an intrinsic endothelial dysfunction. The ability of contracting skeletal muscle to attenuate sympathetic α‐adrenergic vasoconstriction ('functional sympatholysis') is impaired with age. In young adults, increasing endothelium‐dependent vasodilatory signalling during mild exercise augments sympatholysis. In the present study, we tested the hypothesis that increasing endothelium‐dependent signalling during exercise in older adults can improve sympatholysis. In 16 older individuals (Protocol 1, n = 8; Protocol 2, n = 8), we measured forearm blood flow (Doppler ultrasound) and calculated changes in vascular conductance (FVC) to local intra‐arterial infusion of phenylephrine (PE; α1‐agonist) during (i) infusion of an endothelium‐dependent vasodilator alone (Protocol 1: ACh or Protocol 2: low dose ATP); (ii) mild handgrip exercise (5% maximum voluntary contraction; MVC); (iii) moderate handgrip exercise (15% MVC); and (iv) mild or moderate handgrip exercise + infusion of ACh or ATP to augment endothelium‐dependent signalling. PE caused robust vasoconstriction in resting skeletal muscle during control vasodilator infusions (ΔFVC: ACh: −31 ± 3 and ATP: −30 ± 4%). PE‐mediated vasoconstriction was not attenuated by mild or moderate intensity exercise (ΔFVC: 5% MVC: −30 ± 9; 15% MVC: −33 ± 8%; P > 0.05 vs. control ACh and ATP), indicative of impaired sympatholysis, and ACh or ATP infusion during mild exercise did not impact this response. However, augmentation of endothelium‐dependent signalling via infusion of ACh or ATP during moderate intensity exercise attenuated PE‐mediated vasoconstriction (ΔFVC: −13 ± 1 and −19 ± 5%, respectively; P < 0.05 vs. all conditions). Our findings demonstrate that, given a sufficient stimulus, endothelium‐dependent sympatholysis remains intact in older adults. Strategies aimed at activating such pathways represent a viable approach for improving sympatholysis and thus tissue blood flow and oxygen delivery in older adults. Key points: The ability of contracting skeletal muscle to attenuate sympathetic vasoconstriction (functional sympatholysis) is critical for maintaining blood flow during exercise‐mediated sympathoexcitation.Functional sympatholysis and endothelial function are impaired with ageing, resulting in compromised blood flow and oxygen delivery to contracting skeletal muscle during exercise.In the present study, intra‐arterial infusion of ACh or ATP to augment endothelium‐dependent signalling during exercise attenuated α1‐adrenergic vasoconstriction in the contracting muscle of older adults.The vascular signalling mechanisms capable of functional sympatholysis are preserved in healthy ageing, and thus the age‐related impairment in functional sympatholysis probably results from the loss of a functional signal (e.g. plasma [ATP]) as opposed to an intrinsic endothelial dysfunction. [ABSTRACT FROM AUTHOR]

Consumer confidence and trust, as it relates to the food system, is one of the most sensitive areas within consumers' understanding of food. Surveys have shown that a large majority of people would like to learn more about agriculture and food manufacturing, with young people being among those most eager for more information about where their food comes from. Food‐focused educational resources often go unused due to teachers' lack of familiarity with the subject area, the pressures of standardized testing, and lack of alignment to state content standards. Building on the success of the Hands On Classrooms platform that developed and validated curricula with high adoption rates by teachers and a demonstrated impact on student knowledge and self‐efficacy, a new curriculum on food system and food processing was developed and pilot tested. Two teachers from rural Virginia and Tennessee participated in the study. Both teachers received online professional development prior to implementation. Students were given pretests and posttests to measure (a) what impact does the curriculum have on students' knowledge of food systems and processing and (b) to what extent does the curriculum have an impact on student's self‐reported skills related to these topics? A total of 87 students completed the assessments and showed significant improvements from pretest to posttest on both knowledge (p <.001) and skills (p <.001) related specifically to where food comes from and how it is processed, content that is typically not covered in middle school curriculum. Further research can be undertaken to measure the impact on others in different geographic and socioeconomic areas to provide additional data to validate the program. [ABSTRACT FROM AUTHOR]

Mathematics and science education researchers focused on teacher education emphasize attention and responsiveness to student thinking as central to effective classroom practice. Being responsive to student thinking involves attending to the substance of students' ideas—the meaning students are making—and pursuing that thinking, adjusting the flow of instruction as needed. Yet, attention and responsiveness to student thinking is irregular and generally rare among novice teachers. In this theoretical paper, we argue that the irregularity of attention and responsiveness to student thinking, including variability within individual teachers' practice, can be explained by a framework grounded in teachers' localized framings of their classroom activity—their sense of "what is it that's going on here." Using analyses of classroom episodes across contexts and timescales to illustrate our claims, we demonstrate how a framing-anchored framework can coordinate and improve upon three common explanations for the irregularity of novice teachers' attention and responsiveness to student thinking: underdeveloped skills and/or knowledge for attending and responding, "transmissionist" beliefs about learning, and institutional constraints (and teachers' perceptions thereof). Building on this argument, we suggest that teacher educators can work with novice teachers' framings of their classroom activities as a generative anchor for supporting attention and responsiveness to student thinking in classroom settings. [ABSTRACT FROM AUTHOR]

Premise: The southern Florida Everglades landscape sustains wetlands of national and international importance. Sawgrass (Cladium jamaicense), the dominant macrophyte in the Everglades, has two phenotypes that vary in size and density between Everglades marl prairies and peat marshes. Marl prairies have recently been hypothesized to be a newly formed habitat developed after European colonization as a result of landscape‐scale hydrologic modifications, implying that sawgrass marl phenotypes developed in response to the marl habitat. We examined whether sawgrass wetland phenotypes are plastic responses to marl and peat soils. Methods: In a common‐mesocosm experiment, seedlings from a single Everglades population were grown outdoors in field‐collected marl or peat soils. Growth and morphology of plants were measured over 14 mo, while soil and leaf total nitrogen, total phosphorus, total carbon, and plant biomass and biomass allocation were determined in a final harvest. Results: Sawgrass plant morphology diverged in marl vs. peat soils, and variations in morphology and density of mesocosm‐grown plants resembled differences seen in sawgrass plants growing in marl and peat habitats in Everglades wetlands. Additionally, sawgrass growing in marl made abundant dauciform roots, while dauciform root production of sawgrass growing in peat was correlated with soil total phosphorus. Conclusions: Sawgrass from a single population grown in marl or peat soils can mimic sawgrass phenotypes associated with marl vs. peat habitats. This plasticity is consistent with the hypothesis that Everglades marl prairies are relatively new habitats that support plant communities assembled after European colonization and subsequent landscape modifications. [ABSTRACT FROM AUTHOR]

Key points: In humans, the vasodilatory response to skeletal muscle contraction is mediated in part by activation of inwardly rectifying potassium (KIR) channels. Evidence from animal models suggest that KIR channels serve as electrical amplifiers of endothelium‐dependent hyperpolarization (EDH).We found that skeletal muscle contraction amplifies vasodilatation to the endothelium‐dependent agonist ACh, whereas there was no change in the vasodilatory response to sodium nitroprusside, an endothelium‐independent nitric oxide donor.Blockade of KIR channels reduced the exercise‐induced amplification of ACh‐mediated vasodilatation. Conversely, pharmacological activation of KIR channels in quiescent muscle via intra‐arterial infusion of KCl independently amplified the vasodilatory response to ACh.This study is the first in humans to demonstrate that specific endothelium‐dependent vasodilatory signalling is amplified in the vasculature of contracting skeletal muscle and that KIR channels may serve as amplifiers of EDH‐like vasodilatory signalling in humans. The local vasodilatory response to muscle contraction is due in part to the activation of inwardly rectifying potassium (KIR) channels. Evidence from animal models suggest that KIR channels function as 'amplifiers' of endothelium‐dependent vasodilators. We tested the hypothesis that contracting muscle selectively amplifies endothelium‐dependent vasodilatation via activation of KIR channels. We measured forearm blood flow (Doppler ultrasound) and calculated changes in vascular conductance (FVC) to local intra‐arterial infusion of ACh (endothelium‐dependent dilator) during resting conditions, handgrip exercise (5% maximum voluntary contraction) or sodium nitroprusside (SNP; endothelium‐independent dilator) which served as a high‐flow control condition (n = 7, young healthy men and women). Trials were performed before and after blockade of KIR channels via infusion of barium chloride. Exercise augmented peak ACh‐mediated vasodilatation (ΔFVC saline: 117 ± 14; exercise: 236 ± 21 ml min−1 (100 mmHg)−1; P < 0.05), whereas SNP did not impact ACh‐mediated vasodilatation. Blockade of KIR channels attenuated the exercise‐induced augmentation of ACh. In eight additional subjects, SNP was administered as the experimental dilator. In contrast to ACh, exercise did not alter SNP‐mediated vasodilatation (ΔFVC saline: 158 ± 35; exercise: 121 ± 22 ml min−1 (100 mmHg)−1; n.s.). Finally, in a subset of six subjects, direct pharmacological activation of KIR channels in quiescent muscle via infusion of KCl amplified peak ACh‐mediated vasodilatation (ΔFVC saline: 97 ± 15, KCl: 142 ± 16 ml min−1 (100 mmHg)−1; respectively; P < 0.05). These findings indicate that skeletal muscle contractions selectively amplify endothelium‐dependent vasodilatory signalling via activation of KIR channels, and this may be an important mechanism contributing to the normal vasodilatory response to exercise in humans. Key points: In humans, the vasodilatory response to skeletal muscle contraction is mediated in part by activation of inwardly rectifying potassium (KIR) channels. Evidence from animal models suggest that KIR channels serve as electrical amplifiers of endothelium‐dependent hyperpolarization (EDH).We found that skeletal muscle contraction amplifies vasodilatation to the endothelium‐dependent agonist ACh, whereas there was no change in the vasodilatory response to sodium nitroprusside, an endothelium‐independent nitric oxide donor.Blockade of KIR channels reduced the exercise‐induced amplification of ACh‐mediated vasodilatation. Conversely, pharmacological activation of KIR channels in quiescent muscle via intra‐arterial infusion of KCl independently amplified the vasodilatory response to ACh.This study is the first in humans to demonstrate that specific endothelium‐dependent vasodilatory signalling is amplified in the vasculature of contracting skeletal muscle and that KIR channels may serve as amplifiers of EDH‐like vasodilatory signalling in humans. [ABSTRACT FROM AUTHOR]

Vegetative branching is common in the palms (Arecaceae). However, current terms to describe vegetative branching diversity are not consistent and do not cover the full range of branching types. In this study vegetative branching types in the palms were reviewed and defined, and the phylogenetic distribution of palm branching types was described. Branching types were described from a literature review and field observations; 1903 species representing all 181 genera were included. Five branching types were found: lateral axillary branching, shoot apical division, false vivipary, abaxial branching, and leaf-opposed branching. Most species (55%) exhibited no vegetative branching. Lateral axillary was the most common branching type. Lateral axillary branching and shoot apical division were predicted to be the earliest-evolved branching types. The present study suggests that branching types have different evolutionary histories, and it is likely that the solitary habit is more common now than when palms initially diverged from commelinid relatives. [ABSTRACT FROM AUTHOR]

This special issue is dedicated to the memory of Xavier Bisaro (June 21, 1972–June 17, 2018). Bisaro was professor of musicology at the Université François Rabelais de Tours, a research fellow at the Centre d'Études Supérieures de la Renaissance, and a junior member of the Institut Universitaire de France. His work was principally dedicated to the study of music and liturgy in the early modern period. His most recent project was "Cantus Scholarum: Le chant scolaire dans l'Europe moderne," https://www.cantus-scholarum.univ-tours.fr/#. [ABSTRACT FROM AUTHOR]

Clonal growth can vary under different environmental conditions, and differences in clonal growth in the juvenile stage influence adult architecture. Acoelorrhaphe wrightii, a threatened palm in Florida, can occur as solitary or clonal. In order to predict its adult architecture, we determined the effects of water and light on (1) germination and (2) morphology of A. wrightii during juvenile life stages. Germination of wild‐collected seeds exposed to four conditions–subsurface, saturated, low, and high water levels–was monitored every month for a year. Seeds began to germinate after seven months; soils with saturated water levels had highest seed germination. Sixty‐four juveniles were grown in one of four environmental treatments (low water + sun, low water + shade, high water + sun, and high water + shade) and growth was measured every two months for a year. After a year, individuals were harvested to assess the impact of treatments on plant biomass. Low water + sun yielded juveniles with a greater number of leaves, more root mass and more branches. The results of this study suggest that A. wrightii requires a dry‐down in order to recruit successfully. Results were used to model the effect of water level on adult vegetative architecture. [ABSTRACT FROM AUTHOR]

Dietary nitrate (NO-3 ) is converted to nitrite (NO-2 ) and can be further reduced to the vasodilator nitric oxide (NO) amid a low O2 environment. Accordingly, dietary NO-3 increases hind limb blood flow in rats during treadmill exercise; however, the evidence of such an effect in humans is unclear. We tested the hypothesis that acute dietary NO-3 (via beetroot [BR] juice) increases forearm blood flow (FBF) via local vasodilation during handgrip exercise in young adults (n = 11; 25 - 2 years). FBF (Doppler ultrasound) and blood pressure (Finapres) were measured at rest and during graded handgrip exercise at 5%, 15%, and 25% maximal voluntary contraction (MVC) lasting 4 min each. At the highest workload (25% MVC), systemic hypoxia (80% SaO2) was induced and exercise continued for three additional minutes. Subjects ingested concentrated BR (12.6 mmol nitrate (n = 5) or 16.8 mmol nitrate (n = 6) and repeated the exercise bout either 2 (12.6 mmol) or 3 h (16.8 mmol) postconsumption. Compared to control, BR significantly increased FBF at 15% MVC (184 ±15 vs. 164 - 15 mL/min), 25% MVC (323 ±27 vs. 286 ±28 mL/min), and 25% + hypoxia (373 ±39 vs. 343 ±32 mL/min) and this was due to increases in vascular conductance (i.e., vasodilation). The effect of BR on hemodynamics was not different between the two doses of BR ingested. Forearm VO2 was also elevated during exercise at 15% and 25% MVC. We conclude that acute increases in circulating NO-3 and NO-2 via BR increases muscle blood flow during moderate- to high-intensity handgrip exercise via local vasodilation. These findings may have important implications for aging and diseased populations that demonstrate impaired muscle perfusion and exercise intolerance. [ABSTRACT FROM AUTHOR]

Key points Intravascular ATP attenuates sympathetic vasoconstriction (sympatholysis) similar to what is observed in contracting skeletal muscle of humans, and may be an important contributor to exercise hyperaemia., Similar to exercise, ATP-mediated vasodilatation occurs via activation of inwardly rectifying potassium channels (KIR), and synthesis of nitric oxide (NO) and prostaglandins (PG)., However, recent evidence suggests that these dilatatory pathways are not obligatory for sympatholysis during exercise; therefore, we tested the hypothesis that the ability of ATP to blunt α1-adrenergic vasoconstriction in resting skeletal muscle would be independent of KIR, NO, PGs and Na+/K+-ATPase activity., Blockade of KIR channels alone or in combination with NO, PGs and Na+/K+-ATPase significantly reduced the vasodilatatory response to ATP, although intravascular ATP maintained the ability to attenuate α1-adrenergic vasoconstriction., This study highlights similarities in the vascular response to ATP and exercise, and further supports a potential role of intravascular ATP in blood flow regulation during exercise in humans., Abstract Exercise and intravascular ATP elicit vasodilatation that is dependent on activation of inwardly rectifying potassium (KIR) channels, with a modest reliance on nitric oxide (NO) and prostaglandin (PG) synthesis. Both exercise and intravascular ATP attenuate sympathetic α-adrenergic vasoconstriction (sympatholysis). However, KIR channels, NO, PGs and Na+/K+-ATPase activity are not obligatory to observe sympatholysis during exercise. To further determine similarities between exercise and intravascular ATP, we tested the hypothesis that inhibition of KIR channels, NO and PG synthesis, and Na+/K+-ATPase would not alter the ability of ATP to blunt α1-adrenergic vasoconstriction. In healthy subjects, we measured forearm blood flow (Doppler ultrasound) and calculated changes in vascular conductance (FVC) to intra-arterial infusion of phenylephrine (PE; α1-agonist) during ATP or control vasodilatator infusion, before and after KIR channel inhibition alone (barium chloride; n = 7; Protocol 1); NO ( l-NMMA) and PG (ketorolac) inhibition alone, or combined NO, PGs, Na+/K+-ATPase (ouabain) and KIR channel inhibition ( n = 6; Protocol 2). ATP attenuated PE-mediated vasoconstriction relative to adenosine (ADO) and sodium nitroprusside (SNP) (PE-mediated ΔFVC: ATP: −16 ± 2; ADO: −38 ± 6; SNP: −59 ± 6%; P < 0.05 vs. ADO and SNP). Blockade of KIR channels alone or combined with NO, PGs and Na+/K+-ATPase, attenuated ATP-mediated vasodilatation (∼35 and ∼60% respectively; P < 0.05 vs. control). However, ATP maintained the ability to blunt PE-mediated vasoconstriction (PE-mediated ΔFVC: KIR blockade alone: −6 ± 5%; combined blockade:−4 ± 14%; P > 0.05 vs. control). These findings demonstrate that intravascular ATP modulates α1-adrenergic vasoconstriction via pathways independent of KIR channels, NO, PGs and Na+/K+-ATPase in humans, consistent with a role for endothelium-derived hyperpolarization in functional sympatholysis. [ABSTRACT FROM AUTHOR]

Sea level rise (SLR) and land-use change are working together to change coastal communities around the world. Along Florida's coast, SLR and large-scale drying are increasing groundwater salinity, resulting in halophytic (salt-tolerant) species colonizing glycophytic (salt-intolerant) communities. We hypothesized that halophytes can contribute to increased soil salinity as they move into glycophyte communities, making soils more saline than SLR or drying alone. We tested our hypothesis with a replacement-series greenhouse experiment with halophyte/glycophyte ratios of 0:4, 1:3, 2:2, 3:1, 4:0, mimicking halophyte movement into glycophyte communities. We subjected replicates to 0, 26, and 38‰ salinity for one, one, and three months, respectively, taking soil salinity and stomatal conductance measurements at the end of each treatment period. Our results showed that soil salinity increased as halophyte/glycophyte ratio increased. Either osmotic or ionic stress caused decreases in glycophyte biomass, resulting in less per-plant transpiration as compared to halophytes. At 38‰ groundwater, soil salinity increased as halophyte density increased, making conditions more conducive to further halophyte establishment. This study suggests that coastal plant community turnover may occur faster than would be predicted from SLR and anthropogenic disturbance alone. [ABSTRACT FROM AUTHOR]

Objectives:Impaired inhibitory control is a key feature of attention-deficit/hyperactivity disorder (ADHD). We investigated gene–environment interaction (GxE) as a possible contributing factor to response inhibition variation in context of the differential susceptibility theory. This states individuals carrying plasticity gene variants will be more disadvantaged in negative, but more advantaged in positive environments. Methods:Behavioural and neural measures of response inhibition were assessed during a Stop-signal task in participants with (N = 197) and without (N = 295) ADHD, fromN = 278 families (age M = 17.18, SD =3.65). We examined GxE between candidate plasticity genes (DAT1,5-HTT,DRD4) and social environments (maternal expressed emotion, peer affiliation). Results:ADRD4× Positive peer affiliation interaction was found on the right fusiform gyrus (rFG) activation during successful inhibition. Further,5-HTTshort allele carriers showed increased rFG activation during failed inhibitions. Maternal warmth and positive peer affiliation were positively associated with right inferior frontal cortex activation during successful inhibition. Deviant peer affiliation was positively related to the error rate. Conclusions:While a pattern of differential genetic susceptibility was found, more clarity on the role of the FG during response inhibition is warranted before firm conclusions can be made. Positive and negative social environments were related to inhibitory control. This extends previous research emphasizing adverse environments. [ABSTRACT FROM PUBLISHER]

Systemic hypoxia is a physiological and pathophysiological stress that activates the sympathoadrenal system and, in young adults, leads to peripheral vasodilation. We tested the hypothesis that peripheral vasodilation to graded systemic hypoxia is impaired in older healthy adults and that this age-associated impairment is due to attenuated α-adrenergic mediated vasodilation and elevated β-adrenergic vasoconstriction. Forearm blood flow was measured (Doppler ultrasound), and vascular conductance (FVC) was calculated in 12 young (24 ± 1 yr) and 10 older (63 ± 2 yr) adults to determine the local dilatory responses to graded hypoxia (90, 85, and 80% O2 saturations) in control conditions, following local intra-arterial blockade of β-receptors (propranolol), and combined blockade of β- and β-receptors (phentolamine + propranolol). Under control conditions, older adults exhibited impaired vasodilation to hypoxia compared with young participants at all levels of hypoxia (peak ΔFVC at 80% SpO2 = 4 ± 6 vs. 35 ± 8%; P < 0.01). During β-blockade, older adults actively constricted at 85 and 80% SpO2 (peak ΔFVC at 80% SpO2 =-13 ± 6%; P < 0.05 vs. control), whereas the response in the young was not significantly impacted (peak ΔFVC = 28 ± 8%). Combined β- and β-blockade increased the dilatory response to hypoxia in young adults; however, older adults failed to significantly vasodilate (peak ΔFVC at 80% SpO2 = 12 ± 11% vs. 58 ± 11%; P < 0.05). Our findings indicate that peripheral vasodilation to graded systemic hypoxia is significantly impaired in older adults, which cannot be fully explained by altered sympathoadrenal control of vascular tone. Thus, the impairment in hypoxic vasodilation is likely due to attenuated local vasodilatory and/or augmented vasoconstrictor signaling with age. [ABSTRACT FROM AUTHOR]

Background: Preterm children face higher risk of cognitive and academic deficits compared with their full-term peers. The objective of this study was to describe early childhood cognitive ability and kindergarten academic achievement across gestational age at birth in a population-based longitudinal cohort.Methods: The study population included singletons born at 24-42 weeks gestation enrolled in the Early Childhood Longitudinal Study-Birth Cohort (n = 6150 for 2-year outcome, n = 4450 for kindergarten outcome). Home-based assessments measured cognitive ability at 2 years and reading and mathematics achievement at kindergarten age. Linear regression models estimated the association between gestational age and cognitive and academic scores using four different ways of modelling gestational age: continuous variable in linear and quadratic terms; categories for individual weeks; and clinical categories for early preterm, moderate preterm, late preterm, early term, full term, late term, and post-term.Results: Children born at early preterm (24-27 weeks), moderate preterm (28-33 weeks), and late preterm (34-36 weeks) scored significantly worse than full-term (39-40 weeks) peers on 2-year and kindergarten assessments; however, no deficits were observed for early term (37-38 weeks). These categories were a clinically useful and parsimonious approach to stratifying risk of adverse cognitive and academic outcomes.Conclusions: This study estimated the relative performance of children born at 24-42 weeks in a population-based birth cohort using multiple approaches to modelling gestational age, providing a more rigorous understanding of the relationships between the full spectrum of gestational age and cognitive and academic outcomes in early childhood and at school age. [ABSTRACT FROM AUTHOR]

The vining fern Lygodium microphyllum (Old World Climbing Fern), which is native to the Old World tropics, has invaded central and southern Florida, disrupting native habitats, reducing biodiversity, and altering fire-line intensity and behavior. Prescribed fire, one of several methods used to manage Old World Climbing Fern infestations, reduces the fern’s above-ground biomass over large areas, but its effects on spore viability are unknown. To determine the heat tolerance of spores, we exposed spores to temperatures ranging from 50 °C to 300 °C for durations of 5 sec to 1 h, then assessed their germination on agar in Petri plates. Temperatures of 50 °C had little effect; 300 °C killed spores for all durations. Results indicate that spore viability decreases with increasing temperature and duration of heat exposure, and that spores are killed at relatively low temperatures (≥100 °C). [ABSTRACT FROM AUTHOR]

The vining fern Lygodium microphyllum (Old World Climbing Fern), which is native to the Old World tropics, has invaded central and southern Florida, disrupting native habitats, reducing biodiversity, and altering fire-line intensity and behavior. Prescribed fire, one of several methods used to manage Old World Climbing Fern infestations, reduces the fern's above-ground biomass over large areas, but its effects on spore viability are unknown. To determine the heat tolerance of spores, we exposed spores to temperatures ranging from 50 °C to 300 °C for durations of 5 sec to 1 h, then assessed their germination on agar in Petri plates. Temperatures of 50 °C had little effect; 300 °C killed spores for all durations. Results indicate that spore viability decreases with increasing temperature and duration of heat exposure, and that spores are killed at relatively low tem peratures (≥100 °C). [ABSTRACT FROM AUTHOR]

Importance: Clinicians have been urged to delay the use of obstetric interventions (eg, labor induction, cesarean delivery) until 39 weeks or later in the absence of maternal or fetal indications for intervention.Objective: To describe recent trends in late preterm and early term birth rates in 6 high-income countries and assess association with use of clinician-initiated obstetric interventions.Design: Retrospective analysis of singleton live births from 2006 to the latest available year (ranging from 2010 to 2015) in Canada, Denmark, Finland, Norway, Sweden, and the United States.Exposures: Use of clinician-initiated obstetric intervention (either labor induction or prelabor cesarean delivery) during delivery.Main Outcomes and Measures: Annual country-specific late preterm (34-36 weeks) and early term (37-38 weeks) birth rates.Results: The study population included 2,415,432 Canadian births in 2006-2014 (4.8% late preterm; 25.3% early term); 305,947 Danish births in 2006-2010 (3.6% late preterm; 18.8% early term); 571,937 Finnish births in 2006-2015 (3.3% late preterm; 16.8% early term); 468,954 Norwegian births in 2006-2013 (3.8% late preterm; 17.2% early term); 737,754 Swedish births in 2006-2012 (3.6% late preterm; 18.7% early term); and 25,788,558 US births in 2006-2014 (6.0% late preterm; 26.9% early term). Late preterm birth rates decreased in Norway (3.9% to 3.5%) and the United States (6.8% to 5.7%). Early term birth rates decreased in Norway (17.6% to 16.8%), Sweden (19.4% to 18.5%), and the United States (30.2% to 24.4%). In the United States, early term birth rates decreased from 33.0% in 2006 to 21.1% in 2014 among births with clinician-initiated obstetric intervention, and from 29.7% in 2006 to 27.1% in 2014 among births without clinician-initiated obstetric intervention. Rates of clinician-initiated obstetric intervention increased among late preterm births in Canada (28.0% to 37.9%), Denmark (22.2% to 25.0%), and Finland (25.1% to 38.5%), and among early term births in Denmark (38.4% to 43.8%) and Finland (29.8% to 40.1%).Conclusions and Relevance: Between 2006 and 2014, late preterm and early term birth rates decreased in the United States, and an association was observed between early term birth rates and decreasing clinician-initiated obstetric interventions. Late preterm births also decreased in Norway, and early term births decreased in Norway and Sweden. Clinician-initiated obstetric interventions increased in some countries but no association was found with rates of late preterm or early term birth. [ABSTRACT FROM AUTHOR]

Smaller total brain and subcortical volumes have been linked to psychopathology including attention-deficit/hyperactivity disorder (ADHD). Identifying mechanisms underlying these alterations, therefore, is of great importance. We investigated the role of gene-environment interactions (GxE) in interindividual variability of total gray matter (GM), caudate, and putamen volumes. Brain volumes were derived from structural magnetic resonance imaging scans in participants with (N = 312) and without ADHD (N = 437) from N = 402 families (age M = 17.00, SD = 3.60). GxE effects between DAT1, 5-HTT, and DRD4 and social environments (maternal expressed warmth and criticism; positive and deviant peer affiliation) as well as the possible moderating effect of age were examined using linear mixed modeling. We also tested whether findings depended on ADHD severity. Deviant peer affiliation was associated with lower caudate volume. Participants with low deviant peer affiliations had larger total GM volumes with increasing age. Likewise, developmentally sensitive GxE effects were found on total GM and putamen volume. For total GM, differential age effects were found for DAT1 9-repeat and HTTLPR L/L genotypes, depending on the amount of positive peer affiliation. For putamen volume, DRD4 7-repeat carriers and DAT1 10/10 homozygotes showed opposite age relations depending on positive peer affiliation and maternal criticism, respectively. All results were independent of ADHD severity. The presence of differential age-dependent GxE effects might explain the diverse and sometimes opposing results of environmental and genetic effects on brain volumes observed so far. [ABSTRACT FROM AUTHOR]

Water depth and flow effects on growth and nutrient content of three marsh plants ( Cladium jamaicense Crantz, Eleocharis cellulosa Torr., and Nymphaea odorata Aiton) and on soil-building were estimated in the Loxahatchee Impoundment Landscape Assessment where macrocosms contain habitats distinguished by relative water depth (deep slough, shallow slough, and mid-ridge) but that differ in flow. We hypothesized that optimal growth would vary with water depth and species, paralleling distributions in the natural environment, and that growth and tissue nutrients would be positively affected by flow. In addition, we hypothesized that plant morphology would influence sediment deposition with the dense growth of C. jamaicense supporting greatest accretion. Our hypotheses were partly supported. Cladium jamaicense unexpectedly grew best in deep sloughs at depths greater than previously reported. Eleocharis cellulosa had a wide depth tolerance and grew best in flowing conditions. Nymphaea odorata grew best in slough habitats. Nutrient contents differed among species and plant parts but were not affected by flow. Soil accretion did not vary with biomass but partially varied with depth and flow, both key factors in conceptual models of vegetation and soil dynamics in wetlands, especially in the Everglades ridge-and-slough topography. [ABSTRACT FROM AUTHOR]

This essay takes seriously Thomas Raynalde's advice in The Womans Booke that women might read this work aloud. The evidence 1 use to sketch the scene of reading includes Raynalde's advice to readers in his long prologue, and also the kind of reading practice that his own writing represents. But I also go outside the text, considering what we know about the experience of listening to a book, and emphasizing the link between this practice and rhetorical education. I also examine the evidence left behind by two male readers: William Ward, who marked his copy of the 1565 edition privately, and Edward Poeton of Petworth, who represented instead a semipublic or shared reading: the evaluation of The Womans Booke and other books of generation by a Midwife and her Deputy in a fictional dialogue "The Midwives Deputie" (ca. 1630s). [ABSTRACT FROM AUTHOR]

Influenza infection in pregnancy can have adverse impacts on maternal, fetal, and infant outcomes. Influenza vaccination in pregnancy is an appealing strategy to protect pregnant women and their infants. The Bill & Melinda Gates Foundation is supporting three large, randomized trials in Nepal, Mali, and South Africa evaluating the efficacy and safety of maternal immunization to prevent influenza disease in pregnant women and their infants <6 months of age. Results from these individual studies are expected in 2014 and 2015. While the results from the three maternal immunization trials are likely to strengthen the evidence base regarding the impact of influenza immunization in pregnancy, expectations for these results should be realistic. For example, evidence from previous influenza vaccine studies – conducted in general, non-pregnant populations – suggests substantial geographic and year-to-year variability in influenza incidence and vaccine efficacy/effectiveness. Since the evidence generated from the three maternal influenza immunization trials will be complementary, in this paper we present a side-by-side description of the three studies as well as the similarities and differences between these trials in terms of study location, design, outcome evaluation, and laboratory and epidemiological methods. We also describe the likely remaining knowledge gap after the results from these trials become available along with a description of the analyses that will be conducted when the results from these individual data are pooled. Moreover, we highlight that additional research on logistics of seasonal influenza vaccine supply, surveillance and strain matching, and optimal delivery strategies for pregnant women will be important for informing global policy related to maternal influenza immunization. [ABSTRACT FROM AUTHOR]

Human aging is associated with reduced skeletal muscle perfusion during exercise, which may be a result of impaired endothelium-dependent dilation and/or attenuated ability to blunt sympathetically mediated vasoconstriction. Intra-arterial infusion of ascorbic acid (AA) increases nitric oxide-mediated vasodilation and forearm blood flow (FBF) during handgrip exercise in older adults, yet it remains unknown whether an acute oral dose can similarly improve FBF or enhance the ability to blunt sympathetic vasoconstriction during exercise. We hypothesized that 1) acute oral AA would improve FBF (Doppler ultrasound) and oxygen consumption (VO2) via local vasodilation during graded rhythmic handgrip exercise in older adults (protocol 1), and 2) AA ingestion would not enhance sympatholysis in older adults during handgrip exercise (protocol 2). In protocol 1 (n = 8; 65 ± 3 yr), AA did not influence FBF or VO2 during rest or 5% maximal voluntary contraction (MVC) exercise, but increased FBF (199 ± 13 vs. 248 ± 16 ml/min and 343 ± 24 vs. 403 ± 33 ml/min; P < 0.05) and VO2 (26 ± 2 vs. 34 ± 3 ml/min and 43 ± 4 vs. 50 ± 5 ml/min; P < 0.05) at both 15 and 25% MVC, respectively. The increased FBF was due to elevations in forearm vascular conductance (FVC). In protocol 2 (n = 10; 63 ± 2 yr), following AA, FBF was similarly elevated during 15% MVC (~20%); however, vasoconstriction to reflex increases in sympathetic activity during -40 mmHg lower-body negative pressure at rest (ΔFVC: -16 ± 3 vs. -16 ± 2%) or during 15% MVC (ΔFVC: -12 ± 2 vs. -11 ± 4%) was unchanged. Our collective results indicate that acute oral ingestion of AA improves muscle blood flow and VO2 during exercise in older adults via local vasodilation. [ABSTRACT FROM AUTHOR]

In a market place crowded with practical rhetoric books what educational value could a challenging work such as Kenneth Burke's A Rhetoric of Motives (1950) possibly have? Burke knows but doesn't use the terminology of the classical art and rather than analysing the persuasive rhetoric of well-known speeches to equip us with strategies, he weaves his way around literary texts, teasing out meanings that their authors something intended, sometimes did not. Yet, despite such difficulties, A Rhetoric of Motives is a practical rhetoric book. It is just that its process of explication teaches us to think well. This essay tries to explain Burke's rethinking of the purpose and contents of a traditional teaching tool-the rhetorical handbook-and defends the value of literary-rhetorical reading that aims to 'equip' citizens to think openly. [ABSTRACT FROM AUTHOR]

Children's cognitive development and academic performance are linked to both fetal and early childhood factors, including preterm birth and family socioeconomic status. We evaluated whether the relationship between preterm birth (PTB) and first grade standardized test performance among Georgia public school students was modified by neighborhood deprivation in early childhood. The Georgia Birth to School cohort followed 327,698 children born in Georgia from 1998 to 2002 through to end-of-year first grade standardized tests. Binomial and log-binomial generalized estimating equations were used to estimate risk differences and risk ratios for the associations of both PTB and the Neighborhood Deprivation Index for the census tract in which each child's mother resided at the time of birth with test failure (versus passing). The presence of additive and multiplicative interaction was assessed. PTB was strongly associated with test failure, with increasing risk for earlier gestational ages. There was positive additive interaction between PTB and neighborhood deprivation. The main effect of PTB versus term birth increased risk of mathematics failure: 15.9% (95%CI: 13.3–18.5%) for early, 5.0% (95% CI: 4.1–5.9%) for moderate, and 1.3% (95%CI: 0.9–1.7%) for late preterm. Each 1 standard deviation increase in neighborhood deprivation was associated with 0.6% increased risk of mathematics failure. For children exposed to both PTB and higher neighborhood deprivation, test failure was 4.8%, 1.5%, and 0.8% greater than the sum of two main effects for early, moderate, and late PTB, respectively. Results were similar, but slightly attenuated, for reading and English/language arts. Our results suggest that PTB and neighborhood deprivation additively interact to produce greater risk among doubly exposed children than would be predicted from the sum of the effects of the two exposures. Understanding socioeconomic disparities in the effect of PTB on academic outcomes at school entry is important for targeting of early childhood interventions. [ABSTRACT FROM AUTHOR]

Children's cognitive development and academic performance are linked to both fetal and early childhood factors, including preterm birth and family socioeconomic status. We evaluated whether the relationship between preterm birth (PTB) and first grade standardized test performance among Georgia public school students was modified by neighborhood deprivation in early childhood. The Georgia Birth to School cohort followed 327,698 children born in Georgia from 1998 to 2002 through to end-of-year first grade standardized tests. Binomial and log-binomial generalized estimating equations were used to estimate risk differences and risk ratios for the associations of both PTB and the Neighborhood Deprivation Index for the census tract in which each child's mother resided at the time of birth with test failure (versus passing). The presence of additive and multiplicative interaction was assessed. PTB was strongly associated with test failure, with increasing risk for earlier gestational ages. There was positive additive interaction between PTB and neighborhood deprivation. The main effect of PTB versus term birth increased risk of mathematics failure: 15.9% (95%CI: 13.3–18.5%) for early, 5.0% (95% CI: 4.1–5.9%) for moderate, and 1.3% (95%CI: 0.9–1.7%) for late preterm. Each 1 standard deviation increase in neighborhood deprivation was associated with 0.6% increased risk of mathematics failure. For children exposed to both PTB and higher neighborhood deprivation, test failure was 4.8%, 1.5%, and 0.8% greater than the sum of two main effects for early, moderate, and late PTB, respectively. Results were similar, but slightly attenuated, for reading and English/language arts. Our results suggest that PTB and neighborhood deprivation additively interact to produce greater risk among doubly exposed children than would be predicted from the sum of the effects of the two exposures. Understanding socioeconomic disparities in the effect of PTB on academic outcomes at school entry is important for targeting of early childhood interventions. [ABSTRACT FROM AUTHOR]

The circulating erythrocyte, by virtue of the regulated release of ATP in response to reduced oxygen (O2) tension, plays a key role in maintaining appropriate perfusion distribution to meet tissue needs. Erythrocytes from individuals with Type 2 diabetes (DM2) fail to release ATP in response to this stimulus. However, the administration of C-peptide and insulin at a 1:1 ratio was shown to restore this important physiological response in humans with DM2. To begin to investigate the mechanisms by which C-peptide influences low O2-induced ATP release, erythrocytes from healthy humans and humans with DM2 were exposed to reduced O2 in a thin-film tonometer, and ATP release under these conditions was compared with release during normoxia. We determined that 1) low O2-induced ATP release from DM2 erythrocytes is rescued by C-peptide in the presence and absence of insulin, 2) the signaling pathway activated by C-peptide in human erythrocytes involves PKC, as well as soluble guanylyl cyclase (sGC) and 3) inhibitors of cGMP degradation rescue low O2-induced ATP release from DM2 erythrocytes. These results provide support for the hypothesis that both PKC and sGC are components of a signaling pathway activated by C-peptide in human erythrocytes. In addition, since both C-peptide and phosphodiesterase 5 inhibitors rescue low O2-induced ATP release from erythrocytes of humans with DM2, their administration to humans with DM2 could aid in the treatment and/or prevention of the vascular disease associated with this condition. [ABSTRACT FROM AUTHOR]

The differential susceptibility theory states that children differ in their susceptibility towards environmental experiences, partially due to plasticity genes. Individuals carrying specific variants in such genes will be more disadvantaged in negative but, conversely, more advantaged in positive environments. Understanding gene-environment interactions may help unravel the causal mechanisms involved in multifactorial psychiatric disorders such as Attention-Deficit/Hyperactivity Disorder (ADHD). The differential susceptibility theory was examined by investigating the presence of interaction effects between maternal expressed emotion (EE; warmth and criticism) and the solitary and combined effects of plasticity genes ( DAT1, DRD4, 5- HTT) on prosocial and antisocial behaviour (measured with parent- and self-reports) in children with ADHD and their siblings ( N = 366, M = 17.11 years, 74.9 % male). Maternal warmth was positively associated with prosocial behaviour and negatively with antisocial behaviour, while maternal criticism was positively associated with antisocial behaviour and negatively with prosocial behaviour. No evidence of differential susceptibility was found. The current study found no evidence for differential susceptibility based on the selected plasticity genes, in spite of strong EE-behaviour associations. It is likely that additional factors play a role in the complex relationship between genes, environment and behaviour. [ABSTRACT FROM AUTHOR]

The common marsh macrophyte Cladium jamaicense (sawgrass) has high levels of fruit abortion. We investigated the phenology of post-fertilization fruit development and of fruit drop in southern Florida, USA, to determine the timing of fruit abortion in relation to fruit shedding. Fruits at two sites were harvested at 2-week intervals, weighed individually and examined for potential viability (PV) to document changes in fruit biomass, morphology, and abortion rate. Fruits shed into 1/4 m 2 traps placed in sawgrass patches at two sites were counted and assayed for PV every one or two weeks in summer 2009 and 2010. Sawgrass sheds fruits from mid-July to September with peak fruit drop in late July to mid-August, 2–2.5 months after flowering. Sawgrass fruits had high rates of abortion that differed among plants and between sites and increased from mid-July through August. One-third to one-half of all fruits shed by a plant over the summer were aborted. Sawgrass plants had late fruit abortion that occurred prior to shedding but after investment in fruit development, producing persistent aborted fruits. A model for the effect of these fruits on seed bank viability predicted levels of 2% seed viability in the seed bank for 50% fruit abortion, similar to values for seed bank germination from the literature. The low percent of viable sawgrass seeds reported here provides a baseline population parameter for Everglades and other Caribbean marsh restoration and indicates the need to determine the input of viable fruits when studying seed banks and/or germination. [ABSTRACT FROM AUTHOR]

In healthy humans, ageing is typically associated with reduced skeletal muscle blood flow and vascular conductance during exercise. Further, there is a marked increase in resting sympathetic nervous system (SNS) activity with age, yet whether augmented SNS-mediated α-adrenergic vasoconstriction contributes to the age-associated impairment in exercisingmuscle blood flow and vascular tone in humans is unknown. We tested the hypothesis that SNS-mediated vasoconstriction is greater in older than young adults and limits muscle (forearm) blood flow (FBF) during graded handgrip exercise (5, 15, 25% maximal voluntary contraction (MVC)). FBF was measured (Doppler ultrasound) and forearm vascular conductance (FVC) was calculated in 11 young (21 ± 1 years) and 12 older (62 ± 2 years) adults in control conditions and during combined local α- and β-adrenoreceptor blockade via intra-arterial infusions of phentolamine and propranolol, respectively. Under control conditions, older adults exhibited significantly lower FBF and FVC at 15% MVC exercise (22.6 ± 1.3 vs. 29 ± 3.3 ml min-1 100 g forearm fat-free mass (FFM)-1 and 21.7 ± 1.2 vs. 33.6 ± 4.0 ml min-1 100 g FFM-1 100 mmHg-1; P < 0.05) and 25% MVC exercise (37.4 ± 1.4 vs. 46.0 ± 4.9 ml min-1 100 g FFM-1 and 33.7 ± 1.4 vs. 49.0 ± 5.7 ml min-1 100 g FFM-1 100 mmHg-1; P < 0.05), whereas there was no age group difference at 5% MVC exercise. Local adrenoreceptor blockade increased FBF and FVC at rest and during exercise in both groups, although the increase in FBF and FVC from rest to steady-state exercise was similar in young and older adults across exercise intensities, and thus the age-associated impairment in FBF and FVC persisted. Our data indicate that during graded intensity handgrip exercise, the reduced FVC and subsequently lower skeletal muscle blood flow in older healthy adults is not due to augmented sympathetic vasoconstriction, but rather due to impairments in local signalling or structural limitations in the peripheral vasculature with advancing age. [ABSTRACT FROM AUTHOR]

It is unclear whether perfectionism is an antecedent of depressive symptoms, a consequence of depressive symptoms, or both. Furthermore, no study has tested reciprocal relations between perfectionism and anxiety symptoms, despite theory suggesting perfectionism both leads to, and results from, anxiety symptoms. We recruited 302 undergraduates and tested reciprocal relations between self-critical perfectionism and depressive and anxiety symptoms using a 12-month, 3-wave longitudinal design. Self-critical perfectionism predicted increases in depressive symptoms; depressive symptoms did not predict changes in self-critical perfectionism. Self-critical perfectionism was also a concomitant of, but not an antecedent or consequence of, anxiety symptoms. Results complement theory suggesting self-critical perfectionism is a vulnerability factor for depressive symptoms. [ABSTRACT FROM AUTHOR]

ATP release from erythrocytes in response to reduced oxygen (O2) tension stimulates local vasodilation, enabling these cells to direct perfusion to areas in skeletal muscle in need of O2. Erythrocytes of humans with type 2 diabetes do not release ATP in response to low O2. Both C-peptide and insulin individually inhibit low O2-induced ATP release from healthy human erythrocytes, yet when coadministered at physiological concentrations and ratios, no inhibition is seen. Here, we determined: that 1) erythrocytes of healthy humans and humans with type 2 diabetes possess a C-peptide receptor (GPR146), 2) the combination of C-peptide and insulin at physiological ratios rescues low O2-induced ATP release from erythrocytes of humans with type 2 diabetes, 3) residual C-peptide levels reported in humans with type 2 diabetes are not adequate to rescue low O2-induced ATP release in the presence of 1 nM insulin, and 4) the effects of C-peptide and insulin are neither altered by increased glucose levels nor explained by changes in erythrocyte deformability. These results suggest that the addition of C-peptide to the treatment regimen for type 2 diabetes could have beneficial effects on tissue oxygenation, which would help to ameliorate the concomitant peripheral vascular disease. [ABSTRACT FROM AUTHOR]

Objective: Attention-deficit/hyperactivity disorder (ADHD) is associated with conflicted parent-child relationships. The underlying mechanisms of this association are not yet fully understood. We investigated the cross-sectional and longitudinal relationships between externalizing psychopathology in children with ADHD, and expressed emotion (EE; warmth and criticism) and psychopathology in mothers. Method: hi this 6-year follow-up study, 385 children with an ADHD combined subtype were included at baseline (mean, 11.5 years, 83.4% male), of which 285 children (74%) were available at follow-up (mean, 17.5 years, 83.5% male). At both time points, measures of child psychopathology (i.e., ADHD severity, oppositional, and conduct problems), maternal EE, and maternal psychopathology (i.e., ADHD and affective problems) were obtained. Results: EE was not significantly correlated over time. At baseline, we found a nominally negative association (p < .05) between maternal warmth and child ADHD severity. At follow-up, maternal criticism was significantly associated with child oppositional problems, and nominally with child conduct problems. Maternal warmth was nominally associated with child oppositional and conduct problems. These associations were independent of maternal psychopathology. No longitudinal associations were found between EE at baseline and child psychopathology at follow-up, or child psychopathology at baseline and EE at follow-up. Conclusions: The results support previous findings of cross-sectional associations between parental EE and child psychopathology. This, together with the finding that EE was not stable over 6 years, suggests that EE is a momentary state measure varying with contextual and developmental factors. EE does not appear to be a risk factor for later externalizing behavior in children with ADHD. [ABSTRACT FROM AUTHOR]