138 research outputs found

    Evidence for Selective Caching by Arctic Ground Squirrels Living in Alpine Meadows in the Yukon

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    Male arctic ground squirrels (Spermophilus parryii) rely on food they cached the previous year for the energy they need to compete for mates each spring. We collected cheek-pouch contents of arctic ground squirrels trapped during three summers (2000–02) as an indication of what squirrels cached. Among adults, both males and females carried material in their cheek pouches, but males did so more frequently than females (4.4% vs. 0.6% of captures). Males carried material later in the summer than females, and also carried different material (seeds and rhizomes as opposed to nesting material). These differences probably reflect different purposes of cheek-pouch contents—females carried material for immediate use, whereas males carried food for caching. Only 24 of over 100 species of vascular plants growing at our alpine study site were carried, and presumably cached, by male arctic ground squirrels. The seeds or rhizomes of one species, Polygonum viviparum, were found in over 90% of cheek-pouch contents examined, even though that species grew at relatively low density and was no more common than another species in the same genus (Polygonum bistorta) that was never found in cheek-pouch contents. Collectively, this evidence indicates that males are highly selective in what species they cache. Many of the species carried by arctic ground squirrels in this study have also been found in Pleistocene fossil caches from central Yukon, indicating that food preferences of this species may have remained stable over time.Les spermophiles arctiques mâles (Spermophilus parryii) dépendent de la nourriture qu’ils ont cachée l’année précédente pour obtenir l’énergie dont ils ont besoin pour se trouver une compagne d’accouplement au printemps. On a recueilli le contenu des abajoues de spermophiles arctiques capturés pendant trois étés (de 2000 à 2002) pour obtenir un aperçu de ce qu’ils emmagasinaient. Les spermophiles adultes, tant mâles que femelles, transportaient des matériaux dans leurs abajoues, mais c’était plus souvent le cas chez les mâles que chez les femelles (4,4 % par rapport à 0,6 % des spermophiles capturés). Les mâles transportaient des matériaux plus tard pendant l’été que les femelles, sans compter que ces matériaux étaient différents (des graines et des rhizomes par opposition à des matériaux destinés à la nidification). Ces différences sont probablement le reflet de la raison d’être différente du contenu des abajoues — les femelles transportaient des matériaux dont elles allaient se servir immédiatement, tandis que les mâles transportaient des aliments qu’ils allaient mettre en réserve. Sur la centaine d’espèces de plantes vasculaires poussant au site alpin que nous avons étudié, seulement 24 d’entre elles étaient présentes. Ces plantes avaient probablement été mises en réserve par les spermophiles arctiques mâles. Les graines ou les rhizomes d’une espèce, soit le Polygonum viviparum, ont été trouvés dans plus de 90 % du contenu des abajoues examiné, même si ces espèces poussaient selon des densités relativement faibles et qu’elles n’étaient pas plus courantes qu’une autre espèce du même genre (Polygonum bistorta) qui ne se retrouvait jamais dans le contenu des abajoues. Dans l’ensemble, cela indique que les mâles font preuve d’une grande sélectivité quant aux espèces qu’ils mettent en réserve. Grand nombre des espèces transportées par les spermophiles arctiques visés par cette étude ont également été retrouvées dans les caches fossiles du Pléistocène du centre du Yukon, ce qui laisse croire que les préférences alimentaires de cette espèce n’ont guère changé au fil du temps

    Regulating the expectation of reward via cognitive strategies

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    Previous emotion regulation research has been successful in altering aversive emotional reactions. It is unclear, however, whether such strategies can also efficiently regulate expectations of reward arising from conditioned stimuli, which can at times be maladaptive (for example, drug cravings). Using a monetary reward-conditioning procedure with cognitive strategies, we observed attenuation in both the physiological (skin conductance) and neural correlates (striatum) of reward expectation as participants engaged in emotion regulation. The expectation of a potential reward elicits positive feelings and aids in the learning of environmental cues that predict future rewards. Central to this process is the role of the striatum, a multifaceted structure that is involved in affective learning and general reward processing across species 1-3 , which is particularly engaged when potential rewards are predicted or anticipated 4-6 . However, this striatum signal can also be maladaptive and correlates with drug specific cravings 7 , potentially increasing urges to partake in risk-seeking behavior 8 . Given this, it is important to understand how to regulate or control the positive feelings associated with reward expectation. One promising method for examining this is the utilization of cognitive strategies commonly used in both social 9 and clinical 8 disciplines. Emotion regulation strategies, for example, have been successful in attenuating aversive emotional reactions that are elicited by various types of negative stimuli 10 , a pattern that is also reflected in neural regions involved in emotion, such as the amygdala, with both behavioral and subcortical neural modulations possibly mediated by prefrontal cortical regions Fifteen participants who gave written consent were presented with an adapted version of a classical conditioning procedure that has been previously used to study aversive learning 13 . Specifically, participants were presented for 4 s with two conditioned stimuli, a blue and a yellow square, that either predicted (CS+) or did not predict (CS-) a potential monetary reward ($4.00; We obtained written informed consent from 15 participants before the experiment. A repeated-measures ANOVA with the SCRs revealed a main effect of type of conditioned stimuli (CS+, CS-; F 1,14 ¼ 15.48, P o 0.001), a main effect of type of instruction (attend, regulate; F 1,14 ¼ 14.75, P o 0.002) and an interaction between the two factors (F 1,14 ¼ 23.51, P o 0.0001; The second contrast (regulate versus attend trials) yielded a variety of cortical regions that have been previously implicated in emotion regulation Our finding that emotion regulation strategies can successfully modulate physiological and neural correlates underlying the expectation of reward in a conditioning procedure is a first step to understanding how top-down modulation may effectively control positive emotions and eventual urges that may arise (for example, drug craving). This is consistent with recent neuroimaging studies suggesting that cognitive strategies modulate subcortical regions involved in aversive emotional processin

    Paradoxical family practices: LGBTQ+ young people, mental health and wellbeing

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    This article will explore how LGBTQ+ young people sustain, and in some cases survive, family relationships. We develop the concept of ‘paradoxical family practices’ and use this to demonstrate the ways in which LGBTQ+ young people manage family life through everyday emotion work. This highlights: (1) how families ordinarily navigate heteronormativity and ‘issues’ of gender/sexuality; (2) the efficacy of ‘paradoxical family practices’ as a conceptual tool; (3) the value of emotion-centred multiple qualitative methods to explore the lives of LGBTQ+ young people and mental health. Findings derive from a small-scale UK study funded by the Wellcome Trust (UNS39780) and were generated through a two-stage methodology comprising digital/paper emotion maps and qualitative interviews with LGBTQ+ young people aged 16–25 (n = 12) followed by diary methods and follow-up interviews (n = 9). Interviews were also completed with ‘family members’ (n = 7)

    Fertility, Living Arrangements, Care and Mobility

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    There are four main interconnecting themes around which the contributions in this book are based. This introductory chapter aims to establish the broad context for the chapters that follow by discussing each of the themes. It does so by setting these themes within the overarching demographic challenge of the twenty-first century – demographic ageing. Each chapter is introduced in the context of the specific theme to which it primarily relates and there is a summary of the data sets used by the contributors to illustrate the wide range of cross-sectional and longitudinal data analysed

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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    Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts

    Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

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    This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin
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