Resting parasympathetic activity is associated with malodor-induced change in perceived foreignness of speakers

INTRODUCTION

To protect against infection, individuals have evolved context-dependent pathogen-avoidant strategies, including selective social behaviors aimed at avoiding foreign individuals who may possess greater risk of infection. Parasympathetic nervous system (PNS) activity is associated with social engagement and regulation of the classical immune system but has not been widely investigated in relation to changes in intergroup perception and the behavioral immune system.

METHOD

The current research investigated the relationship between parasympathetic activity and perceived foreignness of in and outgroup speakers during exposure to a pathogen-relevant odor (butyric acid). High-frequency heart rate variability was measured at rest and while participants rated foreignness of speakers with and without the odor present.

RESULTS

Findings show that exposure to the odor was associated with higher foreignness perceptions of outgroup speakers and lower foreignness perceptions of ingroup speakers. This effect was especially evident among individuals with higher resting parasympathetic activity.

CONCLUSION

These results suggest that the PNS may play a role in changes in social perceptions during a behavioral immune response.

Perceived control, loneliness, early-life stress, and parents' perceptions of stress

The COVID-19 pandemic has highlighted the importance of understanding what contributes to individual variability in experiences of stress. Increases in stress related to the pandemic have been especially pronounced in parents, indicating a need for research examining what factors contribute to parents' perceptions of stress. Here, we assessed the relationship between parents' perceptions of stress, control, loneliness, and experiences of childhood trauma in two populations of caregivers. In Study 1, we examined the relationship between perceptions of stress, control, loneliness, and history of early stress, along with indices of socioeconomic risk and resting parasympathetic nervous systema activity, which has been linked to variability in perceptions of stress, in caregivers of young children. Perceived control, loneliness, childhood stress, and resting parasympathetic nervous system activity predicted caregivers' stress. In Study 2, we replicated these initial findings in a second sample of caregivers. Additionally, we examined how these processes change over time. Caregivers demonstrated significant changes in perceptions of control, loneliness, and stress, and changes in control and childhood trauma history were associated with changes in perceptions of stress. Together these results indicate the importance of assessing how caregivers perceive their environment when examining what contributes to increased risk for stress. Additionally, they suggest that caregivers' stress-related processes are malleable and provide insight into potential targets for interventions aimed at reducing parents' stress.

Estradiol- and progesterone-associated changes in microRNA-induced silencing and reduced anti-seizure efficacy of an antagomir in female mice

About one third of individuals living with epilepsy have treatment-resistant seizures. Alternative therapeutic strategies are thus urgently needed. One potential novel treatment target is microRNA-induced silencing, which is differentially regulated in epilepsy. Inhibitors (antagomirs) of specific microRNAs have shown therapeutic promise in preclinical epilepsy studies; however, these studies were mainly conducted in male rodent models, and research into microRNA regulation in females and by female hormones in epilepsy is scarce. This is problematic because female sex and the menstrual cycle can affect the disease course of epilepsy and may, therefore, also alter the efficacy of potential microRNA-targeted treatments. Here, we used the proconvulsant microRNA miR-324-5p and its target, the potassium channel Kv4.2, as an example to test how microRNA-induced silencing and the efficacy of antagomirs in epilepsy are altered in female mice. We showed that Kv4.2 protein is reduced after seizures in female mice similar to male mice; however, in contrast to male mice, microRNA-induced silencing of Kv4.2 is unchanged, and miR-324-5p activity, as measured by the association with the RNA-induced silencing complex, is reduced in females after seizure. Moreover, a miR-324-5p antagomir does not consistently reduce seizure frequency or increase Kv4.2 in female mice. As a possible underlying mechanism, we found that miR-324-5p activity and silencing of Kv4.2 in the brain were differentially correlated with plasma levels of 17β-estradiol and progesterone. Our results suggest that hormonal fluctuations in sexually mature female mice influence microRNA-induced silencing and could alter the efficacy of potential future microRNA-based treatments for epilepsy in females.Significance StatementMicroRNA-induced silencing is currently investigated in preclinical studies as a potential novel class of treatment target for epilepsy; however, surprisingly little is known about if and how microRNA-induced silencing is regulated by biological sex and if microRNA therapeutics are as effective in females as they are in males. This study shows that microRNA silencing of the potassium channel Kv4.2 and the functional activity of its targeting microRNA, miR-324-5p, change with plasma levels of estrogens and progesterone and that an inhibitor of miR-324-5p is less effective in female mice to suppress seizures. These findings are significant as they suggest microRNA-induced silencing as a novel molecular mechanism contributing to sex differences in epilepsy that could impact future therapy development.

Somatovisceral influences on emotional development

Frameworks of emotional development have tended to focus on how environmental factors shape children's emotion understanding. However, individual experiences of emotion represent a complex interplay between both external environmental inputs and internal somatovisceral signaling. Here, we discuss the importance of afferent signals and coordination between central and peripheral mechanisms in affective response processing. We propose that incorporating somatovisceral theories of emotions into frameworks of emotional development can inform how children understand emotions in themselves and others. We highlight promising directions for future research on emotional development incorporating this perspective, namely afferent cardiac processing and interoception, immune activation, physiological synchrony, and social touch.

Approach motivation and loneliness: Individual differences and parasympathetic activity

Loneliness, or perceived social isolation, is linked to a number of negative long‐term effects on both mental and physical health. However, how an individual responds to feeling lonely may influence their risk for later negative health outcomes. Here, we sought to clarify what influences variability in individuals' motivated responses to loneliness. Specifically, we assessed whether resting parasympathetic activity, a physiological marker linked to flexible adaptation, facilitates increased approach‐oriented behaviors. Seventy‐four adult participants underwent a conditioning paradigm assessing how they approach and avoid rewards and threats. Individuals with higher levels of loneliness and high resting parasympathetic activity were more likely to demonstrate approach behaviors. We discuss these findings in terms of the role resting parasympathetic activity may play in facilitating adaptive responses to feeling socially isolated.

How an individual responds to feeling lonely may influence their risk for later negative health outcomes. The current study provides new insight into what may influence variability in responses to feeling lonely. Individuals with higher resting parasympathetic activity and high levels of loneliness demonstrate increased approach‐oriented behaviors. This suggests loneliness increases approach motivations but only in the presence of other markers of adaptive responding, like high resting parasympathetic activity.

Early life stress and perceived social isolation influence how children use value information to guide behavior

Learning the value of environmental signals and using that information to guide behavior is critical for survival. Stress in childhood may influence these processes, but how it does so is still unclear. This study examined how stressful event exposures and perceived social isolation affect the ability to learn value signals and use that information in 72 children (8–9 years; 29 girls; 65.3% White). Stressful event exposures and perceived social isolation did not influence how children learned value information. But, children with high stressful event exposures and perceived social isolation were worse at using that information. These data suggest alterations in how value information is used, rather than learned, may be one mechanism linking early experiences to later behaviors.

Public understandings of potential policy responses to health inequalities: Evidence from a UK national survey and citizens' juries in three UK cities

A substantial body of research describes the distribution, causes and potential reduction of health inequalities, yet little scholarship examines public understandings of these inequalities. Existing work is dominated by small-scale, qualitative studies of the experiences of specific communities. As a result, we know very little about what broader publics think about health inequalities; and even less about public views of potential policy responses. This is an important gap since previous research shows many researchers and policymakers believe proposals for 'upstream' policies are unlikely to attract sufficient public support to be viable. This mixed methods study combined a nationally representative survey with three two-day citizens' juries exploring public views of health inequalities and potential policy responses in three UK cities (Glasgow, Manchester and Liverpool) in July 2016. Comparing public opinion elicited via a survey to public reasoning generated through deliberative processes offers insight into the formation of public views. The results challenge perceptions that there is a lack of public support for upstream, macro-level policy proposals and instead demonstrate support for proposals aiming to tackle health inequalities via improvements to living and working conditions, with more limited support for proposals targeting individual behavioural change. At the same time, some macro-economic proposals, notably those involving tax increases, proved controversial among study participants and results varied markedly by data source. Our analysis suggests that this results from three intersecting factors: a resistance to ideas viewed as disempowering (which include, fundamentally, the idea that health inequalities exist); the prevalence of individualising and fatalistic discourses, which inform resistance to diverse policy proposals (but especially those that are more 'upstream', macro-level proposals); and a lack of trust in (local and national) government. This suggests that efforts to enhance public support for evidence-informed policy responses to health inequalities may struggle unless these broader challenges are also addressed.

Thinking Clearly About Biology and Childhood Adversity: Next Steps for Continued Progress

In a previous Perspectives article, we described conceptual problems that pose challenges for research on the effects of childhood adversity and offered promising directions for future research on this topic. In a commentary on that article, McLaughlin et al. disagree with some of these criticisms and defend the utility of their current approaches. Here, we briefly summarize where these perspectives overlap and diverge, using the exchange of views to highlight pressing gaps in knowledge that can be addressed through continued empirical research.

Social relationships and children’s perceptions of adversity

Having sensitive, contingent, and supportive social relationships has been linked to more positive outcomes after experiences of early childhood adversity. Traditionally, social relationships are construed as moderators that buffer children from the effects of exposure to adverse events. However, recent data support an alternative view: that supportive social relationships influence children’s later outcomes by shaping their perceptions of safety and stress, regardless of the particular events to which children are exposed. This perspective has implications for understanding vulnerability and resilience in children.

Odour Learning Bees Have Longer Foraging Careers Than Non-learners in a Natural Environment

Individual animals allowed the opportunity to learn generally outperform those prevented from learning, yet, within a species the capacity for learning varies markedly. The evolutionary processes that maintain this variation in learning ability are not yet well understood. Several studies demonstrate links between fitness traits and visual learning, but the selection pressures operating on cognitive traits are likely influenced by multiple sensory modalities. In addition to vision, most animals will use a combination of hearing, olfaction (smell), gustation (taste), and touch to gain information about their environment. Some animals demonstrate individual preference for, or enhanced learning performance using certain senses in relation to particular aspects of their behaviour (e.g., foraging), whereas conspecific individuals may show different preferences. By assessing fitness traits in relation to different sensory modalities we will strengthen our understanding of factors driving observed variation in learning ability. We assessed the relationship between the olfactory learning ability of bumble bees (Bombus terrestris) and their foraging performance in their natural environment. We found that bees which failed to learn this odour-reward association had shorter foraging careers; foraging for fewer days and thus provisioning their colonies with fewer resources. This was not due to a reduced propensity to forage, but may have been due to a reduced ability to return to their colony. When comparing among only individuals that did learn, we found that the rate at which floral resources were collected was similar, regardless of how they performed in the olfactory learning task. Our results demonstrate that an ability to learn olfactory cues can have a positive impact of the foraging performance of B. terrestris in a natural environment, but echo findings of earlier studies on visual learning, which suggest that enhanced learning is not necessarily beneficial for bee foragers provisioning their colony.

Early life stress and development: potential mechanisms for adverse outcomes

BACKGROUND

Chronic and/or extreme stress in early life, often referred to as early adversity, childhood trauma, or early life stress, has been associated with a wide range of adverse effects on development. However, while early life stress has been linked to negative effects on a number of neural systems, the specific mechanisms through which early life stress influences development and individual differences in children's outcomes are still not well understood.

MAIN TEXT

The current paper reviews the existing literature on the neurobiological effects of early life stress and their ties to children's psychological and behavioral development.

CONCLUSIONS

Early life stress has persistent and pervasive effects on prefrontal-hypothalamic-amygdala and dopaminergic circuits that are at least partially mediated by alterations in hypothalamic-pituitary-adrenal axis function. However, to date, this research has primarily utilized methods of assessment that focus solely on children's event exposures. Incorporating assessment of factors that influence children's interpretation of stressors, along with stressful events, has the potential to provide further insight into the mechanisms contributing to individual differences in neurodevelopmental effects of early life stress. This can aid in further elucidating specific mechanisms through which these neurobiological changes influence development and contribute to risk for psychopathology and health disorders.

Youths' processing of emotion information: Responses to chronic and video-based laboratory stress

Integrating multiple sources of information about others' emotional states is critical to making accurate emotional inferences. There is evidence that both acute and chronic stress influence how individuals perceive emotional information. However, there is little research examining how acute and chronic stress interact to impact these processes. The current study examined whether acute and chronic stress interact to influence how children make emotional inferences. Eighty-nine youths (aged 11-15 years) underwent a novel video-based social stressor. Children completed an emotion recognition task prior to and after the stressor in which they saw integrated displays of facial expressions and contexts depicting congruent or incongruent emotional information. Eye tracking assessed changes in attention to the stimuli. Children became more likely to use and attended more to facial information than contextual information when labeling emotions following exposure to acute stress. Moreover, the effect of acute stress on use of facial information to label emotions was stronger for children who experienced higher levels of chronic stress. These data suggest that acute stress shifts attention towards facial information while suppressing processing of other sources of emotional information, and that youths with a history of chronic stress are more susceptible to these effects.

Rethinking Concepts and Categories for Understanding the Neurodevelopmental Effects of Childhood Adversity

Discovering the processes through which early adverse experiences affect children’s nervous-system development, health, and behavior is critically important for developing effective interventions. However, advances in our understanding of these processes have been constrained by conceptualizations that rely on categories of adversity that are overlapping, have vague boundaries, and lack consistent biological evidence. Here, we discuss central problems in understanding the link between early-life adversity and children’s brain development. We conclude by suggesting alternative formulations that hold promise for advancing knowledge about the neurobiological mechanisms through which adversity affects human development.

Increases in loneliness during medical school are associated with increases in individuals' likelihood of mislabeling emotions as negative

Expressions of emotion represent an important and unique source of information about the states of others. Being able to effectively understand expressions of emotions to make inferences about others' internal mental states and use these inferences to guide decision-making and behavior is critical to navigating social relationships. Loneliness, the perception that one lacks social connection, has important functional consequences for how individuals attend to signals of emotions in others. However, it is less clear whether loneliness changes how individuals recognize emotions in others. In medical practitioners, being able to accurately recognize emotional cues from patients is critical to effectively diagnosing and reacting with care to those patients. The current study examines the relationship between changes in loneliness during medical school and students' recognition of emotion in others. Measures of loneliness and emotion recognition were collected from 122 medical students during their first 3 years of medical school at the beginning and end of each academic year. Changes in loneliness were related to changes in emotion detection, with increases in loneliness being associated with decreases in the probability of accurately discriminating sad and angry faces from other expressions, decreases in the probability of mislabeling emotion expressions as happy, and increases in the probability of mislabeling other emotional expressions as pained and angry. This study suggests that changes in loneliness during medical school are associated with increases in students' labeling emotional expressions as negative, possibly by shifting attention to cues of negative emotion and away from cues of positive emotion. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Medical students' empathy positively predicts charitable donation behavior

Empathy is known to motivate prosocial behavior. This relationship, however is complex and influenced by the social context and the type of prosocial behavior. Additionally, empathy is a complex psychological capacity, making it important to examine how different components of empathy influence different prosocial behaviors. The current study uses a unique longitudinal sample to assess how changes in cognitive and affective components of empathy relate to charitable giving. Measures of empathy were collected from medical students in the fall and spring of students' first three years of medical school. After this time, students had the opportunity to donate to charity. Positive changes in students' cognitive empathy predicted their charitable giving, with students who demonstrated greater increases in cognitive empathy giving more money. This study points to an important role for cognitive empathy in certain prosocial behaviors, and suggests that long term changes in empathy influence individual differences in prosocial behavior.

Organometallic compounds as carriers of extraterrestrial cyanide in primitive meteorites

Extraterrestrial delivery of cyanide may have been crucial for the origin of life on Earth since cyanide is involved in the abiotic synthesis of numerous organic compounds found in extant life; however, little is known about the abundance and species of cyanide present in meteorites. Here, we report cyanide abundance in a set of CM chondrites ranging from 50 ± 1 to 2472 ± 38 nmol·g-1, which relates to the degree of aqueous alteration of the meteorite and indicates that parent body processing influenced cyanide abundance. Analysis of the Lewis Cliff 85311 meteorite shows that its releasable cyanide is primarily in the form of [FeII(CN)5(CO)]3- and [FeII(CN)4(CO)2]2-. Meteoritic delivery of iron cyanocarbonyl complexes to early Earth likely provided an important point source of free cyanide. Iron cyanocarbonyl complexes may have served as precursors to the unusual FeII(CN)(CO) moieties that form the catalytic centers of hydrogenases, which are thought to be among the earliest enzymes.

Third-party punishment following observed social rejection

Humans routinely punish others for violating social norms. This behavior is referred to as third-party punishment. Much of the research on this topic has been done in the context of group cooperation and unjust economic interactions. However, little is known about punishment in response to other types of more personal transgressions. In the present study, we sought to determine whether adults would punish an individual after viewing them undeservingly reject a stranger. We experimentally demonstrate that after observing an individual socially reject an unknown victim, individuals will engage in third-party punishment. Individuals who reported feeling upset with the rejecter were most likely to punish, while feeling sorry for the victim was not predictive of punishment behavior. These findings highlight the motivational role of empathic anger in punishing social norm transgressors. Notably, individuals who reported having been bullied in their own pasts were the most likely to punish the rejecter. These results demonstrate how a history of being bullied may make one more attuned to the social rejection of others and in turn may make one more likely to take retributive action on behalf of another. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Observation of Weakened V-V Dimers in the Monoclinic Metallic Phase of Strained VO_{2}

Emergent order at mesoscopic length scales in condensed matter can provide fundamental insight into the underlying competing interactions and their relationship with the order parameter. Using spectromicroscopy, we show that mesoscopic stripe order near the metal-insulator transition (MIT) of strained VO_{2} represents periodic modulations in both crystal symmetry and V-V dimerization. Above the MIT, we unexpectedly find the long-range order of V-V dimer strength and crystal symmetry become dissociated beyond ≈200  nm, whereas the conductivity transition proceeds homogeneously in a narrow temperature range.

Cognitive skills in preterm infants with bronchopulmonary dysplasia at 1 year adjusted and 2 years chronological age

Objective: The objective of this study was to evaluate for decline in cognitive scores from 12 to 24 months of age for preterm infants ≤32 weeks gestational age for those with and without bronchopulmonary dysplasia.Study design: In an observational retrospective study, detailed medical data was collected from the electronic medical records of preterm infants born between January 2009 and December 2015 who had cognitive evaluations using Bayley Scales of Infant Development, 3rd ed (BISD-3) at 12 months corrected gestational age and 24 months chronological age. Infants were divided into three groups, bronchopulmonary dysplasia (BPD), prolonged oxygen requirement that did not meet BPD criteria, or pulmonary insufficiency (PI), and respiratory distress only (RDS). Decline in cognitive functions was based on the BISD-3 standard deviation of 15 points, no decline ≤3.5 point, moderate, > 3.5 to <7.5 points, significant >7.5 points.Results: The sample included 165 preterm infants divided into three groups, BPD, n = 39, PI, n = 79, RDS only, n = 47. The groups did not differ on gender, ethnicity, birthweight or gestational age. The groups did not differ in percent of infants who showed no, moderate or significant decline. In all groups, the percentage of infants showing a cognitive decline of >7.5 points varied from 67% to 76%Conclusion: There was no significant difference in cognitive decline for those with and without BPD. Of note is that a large percentage of infants in each group showed at least one-half standard deviation of cognitive decline across the 12 and 24 months evaluations. Our concern is that correcting for gestational age at 12 months may delay early intervention when significant delays are found at 24 months.

The complexity of empathy during medical school training: evidence for positive changes

CONTEXT

Empathy is an essential aspect of clinical care, associated with improved patient satisfaction, increased adherence to treatment, and fewer malpractice complaints. Previous studies suggest that empathy declines during medical training. However, past research relied on a single narrowly operationalised, self-report measure of empathy. As empathy is a complex socio-emotional construct, it is critical to assess changes across its distinct components using multiple measures in order to better understand how it is influenced by medical training.

METHODS

In a longitudinal study, medical students completed a series of self-report and behavioural measures twice per year during the first 3 years of their study (2012-2015). These included the previously used Jefferson Scale of Physician Empathy (JSPE), designed to assess empathy in the clinical context, the Questionnaire of Cognitive and Affective Empathy (QCAE), designed to assess overall empathy and its main components, and behavioural measures of sensitivity to others' pain and understanding of others' emotions, both of which are important aspects of empathy. The employment of multiple measures allowed for a more complete assessment of medical students' empathy and related processes.

RESULTS

In reflection of findings in previous work, students' empathy assessed by the JSPE decreased over training. However, on the QCAE, aspects of students' empathy, specifically overall cognitive empathy and its subcomponent perspective taking, and the emotion contagion subcomponent of affective empathy improved, whereas the remaining subcomponents remained stable. During medical school, students also exhibited comparable growth in their understanding of others' emotions and increased sensitivity to others' pain.

CONCLUSIONS

Changes in empathy during medical school cannot be simply characterised as representing an overall decline. Indeed, aspects of empathy thought to be valuable in positive physician-patient interactions improve during training. Overall, this study points to the importance of assessing the distinct components of empathy using multiple forms of measurement in order to better understand the mechanisms involved in empathy changes in medical practice.

Academic advocacy in public health: Disciplinary 'duty' or political 'propaganda'?

The role of 'advocacy' within public health attracts considerable debate but is rarely the subject of empirical research. This paper reviews the available literature and presents data from qualitative research (interviews and focus groups conducted in the UK in 2011-2013) involving 147 professionals (working in academia, the public sector, the third sector and policy settings) concerned with public health in the UK. It seeks to address the following questions: (i) What is public health advocacy and how does it relate to research?; (ii) What role (if any) do professionals concerned with public health feel researchers ought to play in advocacy?; and (iii) For those researchers who do engage in advocacy, what are the risks and challenges and to what extent can these be managed/mitigated? In answering these questions, we argue that two deeply contrasting conceptualisations of 'advocacy' exist within public health, the most dominant of which ('representational') centres on strategies for 'selling' public health goals to decision-makers and the wider public. This contrasts with an alternative (less widely employed) conceptualisation of advocacy as 'facilitational'. This approach focuses on working with communities whose voices are often unheard/ignored in policy to enable their views to contribute to debates. We argue that these divergent ways of thinking about advocacy speak to a more fundamental challenge regarding the role of the public in research, policy and practice and the activities that connect these various strands of public health research.

Brief relaxation training is not sufficient to alter tolerance to experimental pain in novices

Relaxation techniques, such as deep breathing and muscle relaxation, are aspects common to most forms of mindfulness training. There is now an abundance of research demonstrating that mindfulness training has beneficial effects across a wide range of clinical conditions, making it an important tool for clinical intervention. One area of extensive research is on the beneficial effects of mindfulness on experiences of pain. However, the mechanisms of these effects are still not well understood. One hypothesis is that the relaxation components of mindfulness training, through alterations in breathing and muscle tension, leads to changes in parasympathetic and sympathetic nervous system functioning which influences pain circuits. The current study seeks to examine how two of the relaxation subcomponents of mindfulness training, deep breathing and muscle relaxation, influence experiences of pain in healthy individuals. Participants were randomized to either a 10 minute deep breathing, progressive muscle relaxation, or control condition after which they were exposed to a cold pain task. Throughout the experiment, measures of parasympathetic and sympathetic nervous system activity were collected to assess how deep breathing and progressive muscle relaxation alter physiological responses, and if these changes moderate any effects of these interventions on responses to pain. There were no differences in participants’ pain tolerances or self-reported pain ratings during the cold pain task or in participants’ physiological responses to the task. Additionally, individual differences in physiological functioning were not related to differences in pain tolerance or pain ratings. Overall this study suggests that the mechanisms through which mindfulness exerts its effects on pain are more complex than merely through physiological changes brought about by altering breathing or muscle tension. This indicates a need for more research examining the specific subcomponents of mindfulness, and how these subcomponents might be acting, to better understand their utility as a clinical treatment.

Fast learning in free-foraging bumble bees is negatively correlated with lifetime resource collection

Despite widespread interest in the potential adaptive value of individual differences in cognition, few studies have attempted to address the question of how variation in learning and memory impacts their performance in natural environments. Using a novel split-colony experimental design we evaluated visual learning performance of foraging naïve bumble bees (Bombus terrestris) in an ecologically relevant associative learning task under controlled laboratory conditions, before monitoring the lifetime foraging performance of the same individual bees in the field. We found appreciable variation among the 85 workers tested in both their learning and foraging performance, which was not predicted by colony membership. However, rather than finding that foragers benefited from enhanced learning performance, we found that fast and slow learners collected food at comparable rates and completed a similar number of foraging bouts per day in the field. Furthermore, bees with better learning abilities foraged for fewer days; suggesting a cost of enhanced learning performance in the wild. As a result, slower learning individuals collected more resources for their colony over the course of their foraging career. These results demonstrate that enhanced cognitive traits are not necessarily beneficial to the foraging performance of individuals or colonies in all environments.

The benefits of being toxic to deter predators depends on prey body size

Many prey have evolved toxins as a defense against predation. Those species that advertise their toxicity to would-be predators with conspicuous warning signals are known as "aposematic." Investment in toxicity by aposematically signaling prey is thought to underpin how aversive prey are to predators; increasing toxicity means that predators learn to avoid prey faster and attack them at lower rates. However, predators' foraging decisions on aposematic prey are determined not only by their toxicity, but also by their nutrient content: predators can trade-off the costs of ingesting toxin with the benefits of acquiring nutrients. Prey body size is a cue that positively correlates with nutrient content, and that varies within and between aposematic species. We predicted that a dose of quinine (known to be toxic to birds) would be a more effective deterrent to avian predators when prey were small compared with when they were large, and that the benefits of possessing toxin would be greater for small-bodied prey. Using an established laboratory protocol of European starlings (Sturnus vulgaris) foraging on mealworms (Tenebrio molitor), we found evidence for increased protection from a dose of quinine for small-bodied compared with large-bodied prey. This shows that larger prey need more toxin to attain the same level of defense as smaller prey, which has implications for the evolution of aposematism and mimicry.

Spontaneous Oligomerization of Nucleotide Alternatives in Aqueous Solutions

On early Earth, a primitive polymer that could spontaneously form from likely available precursors may have preceded both RNA and DNA as the first genetic material. Here, we report that heated aqueous solutions containing 5-hydroxymethyluracil (HMU) result in oligomers of uracil, heated solutions containing 5-hydroxymethylcytosine (HMC) result in oligomers of cytosine, and heated solutions containing both HMU and HMC result in mixed oligomers of uracil and cytosine. Oligomerization of hydroxymethylated pyrimidines, which may have been abundant on the primitive Earth, might have been important in the development of simple informational polymers.

Bumblebee learning and memory is impaired by chronic exposure to a neonicotinoid pesticide

Bumblebees are exposed to pesticides applied for crop protection while foraging on treated plants, with increasing evidence suggesting that this sublethal exposure has implications for pollinator declines. The challenges of navigating and learning to manipulate many different flowers underline the critical role learning plays for the foraging success and survival of bees. We assessed the impacts of both acute and chronic exposure to field-realistic levels of a widely applied neonicotinoid insecticide, thiamethoxam, on bumblebee odour learning and memory. Although bees exposed to acute doses showed conditioned responses less frequently than controls, we found no difference in the number of individuals able to learn at field-realistic exposure levels. However, following chronic pesticide exposure, bees exposed to field-realistic levels learnt more slowly and their short-term memory was significantly impaired following exposure to 2.4 ppb pesticide. These results indicate that field-realistic pesticide exposure can have appreciable impacts on learning and memory, with potential implications for essential individual behaviour and colony fitness.

Metabolic precursors in astrophysical ice analogs: implications for meteorites and comets

We report the synthesis of complex organic compounds including nicotinic and quinolinic acid, two members involved in the nicotinamide adenine dinucleotide (NAD) biosynthetic pathway, in irradiated astrophysical ice analogs. If delivered to Earth by meteorites and comets, these compounds may have contributed to the origin and early evolution of life.

In situ observations of a possible skate nursery off the western Antarctic Peninsula

A dense aggregation of skate egg cases was imaged during a photographic survey of the sea floor along the western Antarctic Peninsula in November 2013. Egg cases were noted in a narrow band between 394 and 443 m depth. Although some skate species in other oceans are known to utilize restricted areas to deposit eggs in great numbers, such nurseries have not been described in the Southern Ocean.

Effects of rare-earth size on the electronic structure of La1−xLuxVO3

The electronic structure of La(1-x)Lu(x)VO(3)(x = 0, 0.2, 0.6 and 1) single crystals has been investigated using soft x-ray absorption spectroscopy, soft x-ray emission spectroscopy, and resonant soft x-ray inelastic scattering to study the effects of rare-earth size. The x-ray absorption and emission spectra at the O K-edge present a progressive evolution with R-site cation, in agreement with local spin density approximation calculations. This evolution with R, together with the temperature dependence of the O K-edge spectra, is attributed to changes in the crystal structure of La(1-x)Lu(x)VO(3). The crystal-field dd. excitations probed by resonant inelastic x-ray scattering at the V L(3)-edge exhibit an increase in energy and enhanced intensity with the decrease of R-site ionic radius, which is mainly attributed to the increased tilting magnitude of the VO(6) octahedra. Upon cooling to ~95 K, the dd* excitations are prominently enhanced in relative Intensity, in agreement with the formation of the Jahn.Teller distortion int he orbital ordering phase. Additionally, the dd* transitions of the mixed compounds are noticeably suppressed with respect to those of the pure compounds, possibly owing to the formation of C-type orbital ordering induced by large R-site size variances.

Individual differences in vagal regulation are related to testosterone responses to observed violence

Observing violent content has been hypothesized to facilitate antisocial behaviors including interpersonal violence. Testosterone is released in response to perceived challenges of social status, often followed by an increase in aggressive behaviors and physiological activation. Prior investigations evaluating the impact of observing violence on autonomic function have focused on sympathetic measures of arousal. Measurement of parasympathetic nervous system (PNS) activity has been neglected, although reduced PNS activity has been associated with antisocial behavior. Consistent with a hierarchical model of the autonomic nervous system (i.e., polyvagal theory), individual differences in PNS activity reflected in respiratory sinus arrhythmia (RSA) were hypothesized to have an inhibitory impact on sympathetic and hormonal reactivity in subjects who were observing a violent video. Autonomic data (i.e., electrodermal activity (EDA), heart rate, and RSA) were collected from forty adult males prior to and while viewing violent sports or a control video. Pre- and post-video saliva samples were assayed for cortisol and testosterone. Participants who viewed the violent video showed increased sympathetic activity compared to controls. In contrast to the sympathetic reactivity to the violent video, there were no significant RSA changes in response to the stimuli, suggesting that viewing violent sports selectively increases sympathetic activity without eliciting PNS withdrawal. However, within the group viewing the violent video, participants with lower RSA during baseline and the observation of violent videos, responded with greater increases in salivary testosterone, suggesting that high parasympathetic tone dampens testosterone reactivity. These individual differences in response to observed violence, associated with higher RSA, may account for some of the improved health, growth, and restoration outcomes across the lifespan, that this segment of the population benefits from.

Direct observation of decoupled structural and electronic transitions and an ambient pressure monocliniclike metallic phase of VO2

We report the simultaneous measurement of the structural and electronic components of the metal-insulator transition (MIT) of VO2 using electron and photoelectron spectroscopies and microscopies. We show that these evolve over different temperature scales, and are separated by an unusual monocliniclike metallic phase. Our results provide conclusive evidence that the new monocliniclike metallic phase, recently identified in high-pressure and nonequilibrium measurements, is accessible in the thermodynamic transition at ambient pressure, and we discuss the implications of these observations on the nature of the MIT in VO2.

Low-energy V t2g orbital excitations in NdVO3

The electronic structure of NdVO(3) and YVO(3) has been investigated as a function of sample temperature using resonant inelastic soft x-ray scattering at the V L(3)-edge. Most of the observed spectral features are in good agreement with an atomic crystal-field multiplet model. However, a low energy feature is observed at ∼ 0.4 eV that cannot be explained by crystal-field arguments. The resonant behaviour of this feature establishes it as due to excitations of the V t(2g) states. Moreover, this feature exhibits a strong sample temperature dependence, reaching maximum intensity in the orbitally-ordered phase of NdVO(3), before becoming suppressed at low temperatures. This behaviour indicates that the origin of this feature is a collective orbital excitation, i.e. the bi-orbiton.

Body size matters for aposematic prey during predator aversion learning

Aposematic prey advertise their toxicity to predators using conspicuous warning signals, which predators learn to use to reduce their intake of toxic prey. Like other types of prey, aposematic prey often differ in body size, both within and between species. Increasing body size can increase signal size, which make larger aposematic prey more detectable but also gives them a more effective and salient deterrent. However, increasing body size also increases the nutritional value of prey, and larger aposematic prey may make a more profitable meal to predators that are trading off the costs of eating toxins with the benefits of ingesting nutrients. We tested if body size, independent of signal size, affected predation of toxic prey as predators learn to reduce their attacks on them. European starlings (Sturnus vulgaris) learned to discriminate between defended (quinine-injected) and undefended (water-injected) mealworm prey (Tenebrio molitor) using visual signals. During this process, we found that birds attacked and ate more defended prey the larger they were. Body size does affect the probability that toxic prey are attacked and eaten, which has implications for the evolutionary dynamics of aposematism and mimicry (where species share the same warning pattern).

Oxytocin receptor gene variation predicts empathic concern and autonomic arousal while perceiving harm to others

Recent research indicates that the neuropeptide oxytocin and the gene for the oxytocin receptor (OXTR) have been implicated in the modulation of various social behaviors, including those related to empathy and sensitivity to others. In this study, we examine the hypothesis that genetic variation in OXTR is associated with autonomic reactions when perceiving others in distress. We also explore the possibility that individual disposition in empathic concern would differ by OXTR genotype. To address these questions, 51 male participants (18-35 years of age), genotyped for OXTR rs53576, viewed a social interaction containing high levels of individual distress and apparent physical pain. Electrodermal activity, a measure of sympathetic nervous system activity, was collected during the presentation of the stimuli. Participants also completed a self-report dispositional measure of empathy prior to starting the study and provided ratings of arousal while viewing the stimuli. OXTR variant rs53576 GG individuals showed increased levels of sympathetic and subjective arousal in response to the stimuli compared to A allele carriers. GG homozygotes also expressed greater levels of empathic concern. These findings support the importance of the oxytocin receptor variation in emotional and physiological reactions to the affective experiences of other conspecifics.

Determination of the individual atomic site contribution to the electronic structure of 3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA)

We have studied the element and orbital-specific electronic structure of thin films of 3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA) using a combination of synchrotron radiation-exited resonant x-ray emission spectroscopy, x-ray absorption spectroscopy, x-ray photoelectron spectroscopy, as well as density functional theory calculations. Resonant and non-resonant x-ray emission spectroscopies were used to measure the C and O 2p partial densities of state in PTCDA. Furthermore, resonant x-ray emission at the C and O K-edges is shown to be able to measure the partial densities of states associated with individual atomic sites. The flat molecular orientation of PTCDA on various substrates is explained in terms of the carbonyl O atom acting as a hydrogen-bond acceptor leading to multiple in-plane intermolecular C=O···H-C hydrogen bonding between carbonyl groups and the perylene core of the neighboring PTCDA molecules. We support this conclusion by comparison of our calculations to measurements of the electronic structure using element-, site-, and orbital-selective C and O K-edge resonant x-ray emission spectroscopy, and photoemission spectroscopy.

Resonant soft-X-ray emission as a bulk probe of correlated electron behavior in metallic SrxCa1-xVO3

The evolution of electron correlation in SrxCa1-xVO3 has been studied using a combination of bulk-sensitive resonant soft x-ray emission spectroscopy, surface-sensitive photoemission spectroscopy, and ab initio band structure calculations. We show that the effect of electron correlation is enhanced at the surface. Strong incoherent Hubbard subbands are found to lie ∼20% closer in energy to the coherent quasiparticle features in surface-sensitive photoemission spectroscopy measurements compared with those from bulk-sensitive resonant soft x-ray emission spectroscopy, and a ∼10% narrowing of the overall bandwidth at the surface is also observed.

The band structure of WO3 and non-rigid-band behaviour in Na0.67WO3 derived from soft x-ray spectroscopy and density functional theory

The electronic structure of single-crystal WO3 and Na0.67WO3 (a sodium-tungsten bronze) has been measured using soft x-ray absorption and resonant soft x-ray emission oxygen K-edge spectroscopies. The spectral features show clear differences in energy and intensity between WO3 and Na0.67WO3. The x-ray emission spectrum of metallic Na0.67WO3 terminates in a distinct Fermi edge. The rigid-band model fails to explain the electronic structure of Na0.67WO3 in terms of a simple addition of electrons to the conduction band of WO3. Instead, Na bonding and Na 3s-O 2p hybridization need to be considered for the sodium-tungsten bronze, along with occupation of the bottom of the conduction band. Furthermore, the anisotropy in the band structure of monoclinic γ-WO3 revealed by the experimental spectra with orbital-resolved geometry is explained via density functional theory calculations. For γ-WO3 itself, good agreement is found between the experimental O K-edge spectra and the theoretical partial density of states of O 2p orbitals. Indirect and direct bandgaps of insulating WO3 are determined from extrapolating separations between spectral leading edges and accounting for the core-hole energy shift in the absorption process. The O 2p non-bonding states show upward band dispersion as a function of incident photon energy for both compounds, which is explained using the calculated band structure and experimental geometry.

Measurement of diabetes stress in older children and adolescents with type 1 diabetes mellitus

OBJECTIVE

Studies indicate general psychological stress plays a role in the glycemic control of individuals with type 1 diabetes mellitus (T1DM). Disease-specific rather than general measures may be more closely related to measures of health outcomes. Therefore, measurement of diabetes-related stress is needed to advance knowledge of significant relationships between stress and glycemic control. The objective of this study was to evaluate the psychometric properties of a measure of diabetes-related stress for youth with T1DM.

RESEARCH DESIGN AND METHODS

A 65-item diabetes stress questionnaire for youths (DSQY) was previously developed for use with older children and adolescents. The DSQY was completed by 417 youths with T1DM and the results were analyzed to determine the factor structure and psychometric properties of the questionnaire, as well as relationships of diabetes stress with demographic and clinical variables.

RESULTS

A factor analysis of the DSQY yielded an eight-factor solution with acceptable internal consistencies. Significant relationships were observed between glycemic control and stress related to parents and dietary issues. While age and socioeconomic status were unrelated with DSQY scores, higher stress was associated with longer diabetes duration, female gender, and racial/ethnic minority status.

CONCLUSIONS

The DSQY is a reliable and valid measure for assessment of diabetes-specific stress in youths with T1DM.

Metacognitive beliefs and processes in clinical anxiety in children

Recent research has explored the role of metacognitive beliefs and processes in clinical anxiety in youth. The aim of this study was to examine the relationship between metacognitions and anxiety in 7- to 12-year-old children with and without clinical anxiety disorders. A secondary aim of the study was to investigate the psychometric properties of the recently developed Metacognitions Questionnaire for Children (MCQ-C). The sample consisted of 83 children (60.2% female; Oceanian 71.1%), comprising 49 children with anxiety disorders and 34 nonclinical children. All children completed self-report measures of anxiety, emotional difficulties, and metacognitions. A subsample of 7- to 8-year-old participants was used to explore whether young children could wholly comprehend all items on the MCQ-C. Positive and negative metacognitive beliefs and cognitive monitoring were significantly correlated with anxiety and emotional difficulties. Clinical children endorsed significantly more negative and more positive metacognitive beliefs than nonclinical children. Each subscale of the MCQ-C had poor internal consistency. Support for the criterion and convergent validity of the MCQ-C was found. The results suggest that certain metacognitions play a role in clinical anxiety in children but that psychometrically and developmentally validated measures of these concepts in younger individuals are needed.

The 'other' in patterns of drinking: a qualitative study of attitudes towards alcohol use among professional, managerial and clerical workers

BACKGROUND

Recent evidence shows that workers in white collar roles consume more alcohol than other groups within the workforce, yet little is known about their views of drinking.

METHODS

Focus groups were conducted in five workplaces to examine the views of white collar workers regarding the effect of alcohol use on personal and professional lives, drinking patterns and perceived norms. Analysis followed the method of constant comparison.

RESULTS

Alcohol use was part of everyday routine. Acceptable consumption and 'excess' were framed around personal experience and ability to function rather than quantity of alcohol consumed. Public health messages or the risk of adverse health consequences had little impact on views of alcohol consumption or reported drinking.

CONCLUSIONS

When developing public health alcohol interventions it is important to consider the views of differing groups within the population. Our sample considered public health messages to be of no relevance to them, rather they reinforced perceptions that their own alcohol use was controlled and acceptable. To develop effective public health alcohol interventions the views of this group should be examined in more detail.

Assessment of technical and biological parameters of volumetric quantitative computed tomography of the foot: a phantom study

SUMMARY

Few studies exist for bone densitometry of the whole foot. A phantom study demonstrated the sources of error and necessary controls for accurate quantitative computed tomography of the foot. A loss in bone mineral density (BMD) in the small foot bones may be an early indicator of diabetic foot complications.

INTRODUCTION

Volumetric quantitative computed tomography (vQCT) facilitates the assessment of pedal bone osteopenia, which, in the presence of peripheral neuropathy, may well be an early sign of diabetic foot deformity. To date, sources and magnitudes of error in foot vQCT measurements have not been reported.

METHODS

Foot phantoms were scanned using a 64-slice CT scanner. Energy (in kilovoltage peak), table height, phantom size and orientation, location of "bone" inserts, insert material, location of calibration phantom, and reconstruction kernel were systematically varied during scan acquisition.

RESULTS

Energy (in kilovoltage peak) and distance from the isocenter (table height) resulted in relative attenuation changes from -5% to 22% and -5% to 0%, respectively, and average BMD changes from -0.9% to 0.0% and -1.1% to 0.3%, respectively, compared to a baseline 120-kVp scan performed at the isocenter. BMD compared to manufacturer-specified values ranged, on average, from -2.2% to 0.9%. Phantom size and location of bone-equivalent material inserts resulted in relative attenuation changes of -1.2% to 1.4% compared to the medium-sized phantom.

CONCLUSION

This study demonstrated that variations in kilovoltage peak and table height can be controlled using a calibration phantom scanned at the same energy and height as a foot phantom; however, error due to soft tissue thickness and location of bones within a foot cannot be controlled using a calibration phantom alone.

The impact of changes in couples' earnings on married women's Social Security benefits

Women's labor force participation and earnings dramatically increased after World War II. Those changes have important implications for women's Social Security benefits. This article uses the Social Security Administration's Modeling Income in the Near Term (version 6) to examine Social Security benefits for current and future beneficiary wives. The projections show that fewer wives in more recent birth cohorts will be eligible for auxiliary benefits as spouses because their earnings are too high. If their husbands die, however, most wives will still be eligible for survivor benefits because, despite the increase in their earnings over time, they still typically have lower earnings than their husbands. Even so, the share of wives who would be ineligible for widow benefits is projected to double between cohorts.