113 research outputs found
Trade-offs between personal immunity and reproduction in the burying beetle, N. vespilloides
We know that parental investment and immune investment are costly processes, but it is unclear which trait will be prioritised when both may be required. Here we address this question using the burying beetle Nicrophorus vespilloides, carrion breeders that exhibit biparental care of young. Our results show that immunosuppression occurs during provision of parental care. We measured Phenoloxidase (PO) on Day 1-8 of the breeding bout and results show a clear decrease in PO immediately from presentation of the breeding resource onwards. Having established baseline immune investment during breeding we then manipulated immune investment at different times by applying a wounding challenge. Beetles were wounded prior to and during the parental care period and reproductive investment quantified. Different effects on reproductive output occur depending on the timing of wounding. Challenging the immune system with wounding prior to breeding does not affect reproductive output and subsequent Lifetime Reproductive Success (LRS). LRS is also unaffected by applying an immune elicitor prior to breeding, though different arms of the immune system are up/downregulated, perhaps indicating a trade-off between cellular and humoral immunity. In contrast, wounding during breeding reduces reproductive output and to the greatest extent if the challenge is applied early in the breeding bout. Despite being immunosuppressed, breeding beetles can still respond to wounding by increasing PO, albeit not to pre-breeding levels. This upregulation of PO during breeding may affect parental investment, resulting in a reduction in reproductive output. The potential role of juvenile hormone in controlling this trade-off is discussed
Social immunity of the family: parental contributions to a public good modulated by brood size.
Social immunity refers to any immune defence that benefits others, besides the individual that mounts the response. Since contributions to social immunity are known to be personally costly, they are contributions to a public good. However, individuals vary in their contributions to this public good and it is unclear why. Here we investigate whether they are responding to contributions made by others with experiments on burying beetle (Nicrophorus vespilloides) families. In this species, females, males and larvae each contribute to social immunity through the application of antimicrobial exudates upon the carrion breeding resource. We show experimentally that mothers reduce their contributions to social immunity when raising large broods, and test two contrasting hypotheses to explain why. Either mothers are treating social immunity as a public good, investing less in social immunity when their offspring collectively contribute more, or mothers are trading off investment in social immunity with investment in parental care. Overall, our experiments yield no evidence to support the existence of a trade-off between social immunity and other parental care traits: we found no evidence of a trade-off in terms of time allocated to each activity, nor did the relationship between social immunity and brood size change with female condition. Instead, and consistent with predictions from models of public goods games, we found that higher quality mothers contributed more to social immunity. Therefore our results suggest that mothers are playing a public goods game with their offspring to determine their personal contribution to the defence of the carrion breeding resource.AD was supported by NERC grant NE/H019731/1 to RMK. ODeG was supported by the Cambridge Trust and the Mexican Council for Science and Technology (CONACyT). RMK was supported in part by ERC Consolidators grant 310785 BALDWINIAN_BEETLES. SCC was supported by a NERC fellowship (NE/H014225/2), CER was supported by a Department for Employment and Learning PhD studentship. We thank A. Backhouse for help in maintaining the burying beetle population. We thank two anonymous reviewers for helpful comments on the manuscript.This is the final version of the article. It was first available from Springer via http://dx.doi.org/10.1007/s10682-015-9806-
Diet modulates the relationship between immune gene expression and functional immune responses
Nutrition is vital to health and the availability of resources has long been acknowledged as a key factor in the ability to fight off parasites, as investing in the immune system is costly. Resources have typically been considered as something of a "black box", with the quantity of available food being used as a proxy for resource limitation. However, food is a complex mixture of macro- and micronutrients, the precise balance of which determines an animal's fitness. Here we use a state-space modelling approach, the Geometric Framework for Nutrition (GFN), to assess for the first time, how the balance and amount of nutrients affects an animal's ability to mount an immune response to a pathogenic infection. Spodoptera littoralis caterpillars were assigned to one of 20 diets that varied in the ratio of macronutrients (protein and carbohydrate) and their calorie content to cover a large region of nutrient space. Caterpillars were then handled or injected with either live or dead Xenorhabdus nematophila bacterial cells. The expression of nine genes (5 immune, 4 non-immune) was measured 20âŻh post immune challenge. For two of the immune genes (PPO and Lysozyme) we also measured the relevant functional immune response in the haemolymph. Gene expression and functional immune responses were then mapped against nutritional intake. The expression of all immune genes was up-regulated by injection with dead bacteria, but only those in the IMD pathway (Moricin and Relish) were substantially up-regulated by both dead and live bacterial challenge. Functional immune responses increased with the protein content of the diet but the expression of immune genes was much less predictable. Our results indicate that diet does play an important role in the ability of an animal to mount an adequate immune response, with the availability of protein being the most important predictor of the functional (physiological) immune response. Importantly, however, immune gene expression responds quite differently to functional immunity and we would caution against using gene expression as a proxy for immune investment, as it is unlikely to be reliable indicator of the immune response, except under specific dietary conditions. [Abstract copyright: Copyright © 2019. Published by Elsevier Ltd.
Creativity and the computer nerd: an exploration of attitudes
This study arises from our concern that many of our best art and design students are failing to make the most of the opportunities provided by IT because of their fear or dislike of computers. This not only deprives them of useful skills, but, even more importantly, deprives many IT based developments of their input. In this paper we investigate the relationship between attitudes to creativity and to computers among students. We quickly discard an approach based on theories of personality types as philosophically and educationally problematic. An approach based on the self-concept of artists and designers, in relation to their own creativity and to their feelings about computers, offers more hope of progress. This means that we do not try to define the attributes of "creative people". Rather, we ask what creativity means to students of art and design and relate these responses to their attitudes to computers. Self-concept depends on how the subjects see themselves within society and culture, and is liable to change as culture changes. One major instrument of cultural change at the present time is the growth of IT itself. We then describe a first attempt at using a psychological method - Kelly's Repertory Grids - to investigate the self-concept of artists and designers. It is hoped to continue with this approach in further studies over the next few years
The transition from diet to blood: Exploring homeostasis in the insect haemolymph nutrient pool
Nutrition is vital to health, but while the link between diet and body nutritional composition is well explored in humans and other vertebrates, this information is not well understood in insects, despite the vital roles they play in ecosystems, and their increasing use as experimental models. Here we used Nutritional Geometry to explore the rapid physiological response to ingested nutrients in the haemolymph nutritional profile of Spodoptera littoralis caterpillars. We ask whether blood nutrients are maintained homeostatically in the face of variable nutritional intake, or if regulation is more flexible for some nutrients than others (allostasis), which allows animals to adapt to stress by responding in a way that prioritises efficiency of responses in the face of tradeâoffs. Caterpillars were placed on 1 of 20 diets, systematically varying in their nutrient ratios (protein: carbohydrate) and density (calorie content), and their consumption was measured. After 48 h, caterpillars were bled, and the macronutrient (protein, carbohydrates and lipids) and nutrient metabolite (amino acids and simple sugars) content of the haemolymph was measured. Proteins comprised 93% of the haemolymph macronutrient pool on average and their concentration increased with protein eaten. The amino acid (AA) pool was dominated by five AAs, and the total pool increased with total nutrient intake. However, the ratio of essential to nonâessential AAs increased as the proportion of protein consumed increased. Carbohydrates were tightly controlled, increasing only on the most extreme carbohydrate intakes. Simple sugars were dominated by glucose and trehalose, and overall, the simple sugar pool showed high levels of homeostasis. Rather than strict homeostasis of blood nutritional properties, an allostatic model seemed to be a better fit for blood nutrient regulation in this generalist herbivore. This flexibility in response to the nutritional composition of the diet may, in part, explain how this species has evolved to extreme dietary generalism and may play a role in its worldwide pest status. Given the range of fitnessârelated processes affected by the haemolymph, future studies should examine the physiological impacts of blood nutrient variation on reproduction, growth and response to infection and the tradeâoffs between them
Embodying limb absence in the negotiation of sexual intimacy
Some people with physical disabilities experience difficulties in forming and maintaining intimate and sexual relationships (Taleporos and McCabe, 2001). Individuals with physical impairments may variously be seen as inferior, ânot up to scratchâ and can be less valued than those thought to embody the cultural ideal of ânormalityâ (Edwards and Imrie, 2003). The loss of an anatomical part such as an arm or a leg can therefore set up a complex series of perceptual, emotional and psychological responses that can limit or prevent individuals from fully experiencing the kinds of intimate relationships that many of their ânon-disabledâ counterparts can more freely enjoy (Oliver, 1990). Drawing on a series of semi-structured interviews and a group visual workshop with five men and two women with varying acquired and congenital limb absences, this study explores the variety of ways in which sexual relationships and intimacies are negotiated and managed. Certain participants reported a great deal of anxiety regarding their perceptions of sexual attractiveness, and experienced feelings of loss of desirability as a sexual partner. Others reported engaging in an âactive management of visual informationâ about the body, through methods of concealment and exposure. Compensatory strategies were also reported as a way to effectively maintain existing intimate relationships. Finally, hyper-masculine or hyper-feminine enactments of sexuality were described within a range of social and intimate contexts as a means to ânormaliseâ the disabled body. The findings of this study provide a richer and more contextualised understanding of the highly complex adjustment process faced by individuals with limb absence, who actively engage in sexual and intimate relationships
Supported discharge service versus Inpatient care Evaluation (SITE): a randomised controlled trial comparing effectiveness of an intensive community care service versus inpatient treatment as usual for adolescents with severe psychiatric disorders: self-harm, functional impairment, and educational and clinical outcomes.
Background: Clinical guidelines recommend intensive community care service treatment (ICCS) to reduce adolescent psychiatric inpatient care. We have previously reported that the addition of ICCS led to a substantial decrease in hospital use and improved school re-integration. Aim: To undertake a randomised controlled trial (RCT) comparing an inpatient admission followed by an early discharge supported by ICCS with usual inpatient admission (treatment as usual; TAU). In this paper, we report the impact of ICCS on self-harm and other clinical and educational outcomes. Method: 106 patients aged 12-18 admitted for psychiatric inpatient care were randomised (1:1) to either ICCS or TAU. Six months after randomization, we compared the two treatment arms on the number and severity of self-harm episodes, the functional impairment, severity of psychiatric symptoms, clinical improvement, reading and mathematical ability, weight, height and the use of psychological therapy and medication.
Results: At six-month follow-up, there were no differences between the two groups on most measures. Patients receiving ICCS were significantly less likely to report multiple episodes (5 or more) of self-harm (OR=0·18, 95% CI: 0·05 to 0·64). Patients admitted to private inpatient units spent on average 118.4 (95% CI: 28·2 to 208.6) fewer days in hospitals if they were in the ICCS group compared to TAU.
Conclusion: The addition of ICCS to TAU may lower the risk of multiple self-harm and may reduce the duration of inpatient stay, especially in those patients admitted for private care. Early discharge with ICCS appears to be a viable alternative to standard inpatient treatment
Exploring young peopleâs experiences and perceptions of mental health and well-being using photography
© 2019 Association for Child and Adolescent Mental Health Introduction: The mental health of young people is a major global public health concern. A shift in focus towards children and young peopleâs mental health in the UK has emphasized young peopleâs voices, as of paramount importance in shaping the path for future quality care provision. The paper examines a study that aimed to explore young peopleâs perceptions of mental health and well-being using photographs. Method: The methodology employed for this study placed young people at the centre of the research process by using photographs to capture their experiences. Ten young people who attended a youth group used disposable cameras to take photographs of their experiences and perceptions of mental health and well-being. Semi-structured interviews with the young people elicited their narratives behind the images. Data were analysed using photo-elicitation and thematic analysis. Findings: Young peopleâs experiences of mental health and well-being were internalized and located predominantly in the private and hidden regions of their everyday lives. Stigma, social isolation and marginalization were prevalent whilst spirituality and connection with the environment expressed hope. Conclusion: Mental health appears to be firmly located in the private âback regionsâ of young individualsâ lives, demonstrating that young people conceptualize these experiences as a vulnerable and hidden part of their being. Understanding the needs of this new generation of youth including the prevalence of stigma, risk of isolation and social exclusion are paramount. Future service provision needs to recognize the extent stigma impacts upon young peopleâs experiences of mental health and well-being
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