3,774 research outputs found

    Physiological effects of diet mixing on consumer fitness: a meta-analysis

    Get PDF
    The degree of dietary generalism among consumers has important consequences for population, community, and ecosystem processes, yet the effects on consumer fitness of mixing food types have not been examined comprehensively. We conducted a meta-analysis of 161 peer-reviewed studies reporting 493 experimental manipulations of prey diversity to test whether diet mixing enhances consumer fitness based on the intrinsic nutritional quality of foods and consumer physiology. Averaged across studies, mixed diets conferred significantly higher fitness than the average of single-species diets, but not the best single prey species. More than half of individual experiments, however, showed maximal growth and reproduction on mixed diets, consistent with the predicted benefits of a balanced diet. Mixed diets including chemically defended prey were no better than the average prey type, opposing the prediction that a diverse diet dilutes toxins. Finally, mixed-model analysis showed that the effect of diet mixing was stronger for herbivores than for higher trophic levels. The generally weak evidence for the nutritional benefits of diet mixing in these primarily laboratory experiments suggests that diet generalism is not strongly favored by the inherent physiological benefits of mixing food types, but is more likely driven by ecological and environmental influences on consumer foraging

    On the nature of the omega tri-layer periodicity in rapidly cooled Ti-15Mo

    Get PDF
    High angle annular dark field (HAADF) images of the omega phase in metastable beta titanium alloys exhibit tri-layered periodicity. However, it is unclear if this indicates preferential site occupation, or is related to the structural modification of omega formation. Here, the periodicity was studied using a combination of HAADF imaging and electron energy loss spectroscopy. The results show that there is no preferential site occupancy or ordering and that the observed intensity variations are related to the imaging conditions.This work was supported by the Rolls-Royce/EPSRC Strategic Partnership (EP/H022309/1, EP/H500375/1 & EP/M005607/1).This is the final version. It was first published by Elsevier at http://www.sciencedirect.com/science/article/pii/S1359646215002213

    Phase equilibria in the Fe-Mo-Ti ternary system at 1000 °C

    Get PDF
    An isothermal section of the Fe-Mo-Ti ternary system at 1000 °C has been constructed using data acquired from a series of seven alloys. The limit of solubility of Fe in the continuous A2 phase field between Ti and Mo has been determined, as have the extents to which Mo may be accommodated in the B2 TiFe phase, and Ti in the D85_5 Fe7_7Mo6_6 phase. The B2, D85_5 and C14 Fe2_2 (Ti, Mo) intermetallics were found to have limited tolerance for non-stoichiometric compositions. The positions of the A2 + B2 + C14 and A2 + C14 + D85_5 three-phase fields were determined, along with the extents of the A2 + B2, A2 + D85_5, A2 + C14, C14 + B2 and C14 + D85_5 two-phase fields. No ternary phases were observed in any of the alloys studied.This work was support by the Rolls-Royce/EPSRC Strategic Partnership under EP/H022309/1, EP/H500375/1 and EP/M005607/1.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.ijrmhm.2016.07.00

    Linking Maternal Socialization of Emotion Regulation to Adolescents’ Co-rumination With Peers

    Get PDF
    Mounting research supports that co-rumination, the tendency to seek peer support by engaging in extensive negatively focused discussion, is a risk factor for adolescent psychopathology. It is unclear, though, how this interpersonal tendency develops. Parental responses to adolescents’ negative affect likely shape how youth utilize peer relationships to regulate distress, as they shift to reliance on peer support during this developmental stage. For example, nonsupportive parental responses may fail to instill healthy regulation strategies, resulting in ineffective forms of peer support, such as co-rumination. Conversely, high levels of supportive parental responses to adolescents’ negative affect may motivate youth to also express more negative affect with peers, leading to co-rumination. Eighty-nine healthy adolescents (9-17) and their mothers completed surveys and a support-seeking interaction. Only supportive maternal responses, including maternal affection, were associated with adolescents’ co-rumination. These analyses indicate that some forms of parental support are associated with adolescents’ tendency to co-ruminate

    Bohmian Philosophy of Mind?

    Get PDF
    Bohm’s theory is in many ways an attractive solution to the measurement problem in quantum mechanics. It provides an intuitive explanation for the distinctive quantum phenomena of interference and entanglement without the need for any problematic “collapse” of the wave function. But it faces several serious difficulties. First, the dynamical law via which the wave function “pushes around” the Bohmian particles is explicitly non-local, against the spirit of special relativity (Bell 1987, 115). Second, the Bohmian particles can be seen as redundant in the context of an Everettian solution to the measurement problem (Brown and Wallace 2005). And third, the Bohmian solution to the measurement problem apparently depends on an implausible and problematic account of mental awareness (Stone 1994; Brown and Wallace 2005). I do not wish to minimize the significance of the first two difficulties; they are serious threats to the tenability of Bohm’s theory. But the third difficulty, I think, rests on a confusion concerning the way in which Bohmian particles encode the outcomes of measurements. In particular, my concern here is to respond to the accusations of Stone (1994) and Brown and Wallace (2005) that Bohm’s theory requires a mysterious kind of direct awareness of the positions of the Bohmian particles in our brains, and also to the claim of Brown and Wallace (2005) that such direct awareness threatens the quantum no-signaling theorem

    The use of Raman spectroscopy to identify and grade prostatic adenocarcinoma in vitro.

    Get PDF
    PublishedClinical TrialJournal ArticleThis is the final version of the article. Available from Cancer Research UK via the DOI in this record.Raman spectroscopy is an optical technique, which provides a measure of the molecular composition of tissue. Raman spectra were recorded in vitro from both benign and malignant prostate biopsies, and used to construct a diagnostic algorithm. The algorithm was able to correctly identify each pathological group studied with an overall accuracy of 89%. The technique shows promise as a method for objectively grading prostate cancer

    Depressed Adolescents’ Pupillary Response to Peer Acceptance and Rejection: The Role of Rumination

    Get PDF
    Heightened emotional reactivity to peer feedback is predictive of adolescents’ depression risk. Examining variation in emotional reactivity within currently depressed adolescents may identify subgroups that struggle the most with these daily interactions. We tested whether trait rumination, which amplifies emotional reactions, explained variance in depressed adolescents’ physiological reactivity to peer feedback, hypothesizing that rumination would be associated with greater pupillary response to peer rejection and diminished response to peer acceptance. Twenty currently depressed adolescents (12–17) completed a virtual peer interaction paradigm where they received fictitious rejection and acceptance feedback. Pupillary response provided a time-sensitive index of physiological arousal. Rumination was associated with greater initial pupil dilation to both peer rejection and acceptance, and diminished late pupillary response to peer acceptance trials only. Results indicate that depressed adolescents high on trait rumination are more reactive to social feedback regardless of valence, but fail to sustain cognitive-affective load on positive feedback

    Duffy antigen receptor for chemokines and CXCL5 are essential for the recruitment of neutrophils in a multicellular model of rheumatoid arthritis synovium

    Get PDF
    OBJECTIVE: The role of chemokines and their transporters are poorly described in rheumatoid arthritis (RA). Evidence suggests that CXCL5 plays an important role as it is abundant in RA tissue and its neutralization moderates joint damage in animal models of arthritis. The chemokine transporter, Duffy Antigen Receptor for Chemokines (DARC), is also upregulated in early RA. Here we investigate the role of CXCL5 and DARC in regulating neutrophil recruitment using an in vitro model of the RA synovium. METHODS: To model the RA synovium, rheumatoid fibroblasts (RAF) were cocultured with endothelial cells (EC) for 24h. Gene expression in cocultured cells was investigated using TaqMan gene arrays. Roles of CXCL5 and DARC were determined by incorporating cocultures into a flow-based adhesion assay, where their function was demonstrated by blocking neutrophil recruitment with neutralizing reagents. RESULTS: EC-RAF coculture induced chemokine expression in both cell types. While CXC chemokines were modestly upregulated in EC, CXCL1, CXCL5 and CXCL8 expression were greatly increased in RAF. RAF also promoted the recruitment of flowing neutrophils to EC. Anti-CXCL5 antibody abolished neutrophil recruitment by neutralizing CXCL5 expressed on EC, or when used to immuno-deplete coculture conditioned medium. DARC was also induced on EC by coculture and an anti-Fy6 antibody or siRNA targeting of DARC expression effectively abolished neutrophil recruitment. CONCLUSION: For the first time in a model of human disease, the function of DARC has been demonstrated as essential for editing the chemokine signals presented by EC and for promoting unwanted leukocyte recruitment
    • …
    corecore