8,604 research outputs found

    The TLR2/6 ligand PAM2CSK4 is a Th2 polarizing adjuvant in Leishmania major and Brugia malayi murine vaccine models.

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    Toll-like receptors (TLRs) play an important role in the innate and adaptive immune responses to pathogens, and are the target of new vaccine adjuvants. TLR2 plays a role in parasite recognition and activation of immune responses during cutaneous leishmaniasis infection, suggesting that TLR2 could be targeted by adjuvants for use in Leishmania vaccines. We therefore explored using Pam2CSK4 (Pam2) and Pam3CSK4 (Pam3) lipopeptide adjuvants, which activate TLR2/6 and TLR2/1 heterodimers respectively, in vaccine models for parasitic infections.The use of lipopeptide adjuvants was explored using two vaccine models. For cutaneous leishmaniasis, the lipopeptide adjuvants Pam2 and Pam3 were compared to that of the Th1-driving double-stranded DNA TLR9 agonist CpG for their ability to improve the efficacy of the autoclaved Leishmania major (ALM) vaccine to protect against L. major infection. The ability of Pam2 to enhance the efficacy of a soluble Brugia malayi microfilariae extract (BmMfE) vaccine to protect against filarial infection was also assessed in a peritoneal infection model of B. malayi filariasis. Parasite antigen-specific cellular and humoral immune responses were assessed post-challenge.The use of lipopeptides in ALM-containing vaccines did not provide any protection upon infection with L. major, and Pam2 exacerbated the disease severity in vaccinated mice post-challenge. Pam2, and to a lesser extent Pam3, were able to elevate antigen-specific immune responses post-challenge in this model, but these responses displayed a skewed Th2 phenotype as characterised by elevated levels of IgG1. In the B. malayi vaccine model, the use of Pam2 as an adjuvant with BmMfE induced significant protective immunity to the same level as inclusion of an Alum adjuvant. Here, both Pam2 and Alum were found to enhance antigen-specific antibody production post-challenge, and Pam2 significantly elevated levels of antigen-specific IL-4, IL-5 and IL-13 produced by splenocytes.These data indicate that TLR2/6-targeting ligands could be considered as adjuvants for vaccines that require robust Th2 and/or antibody-dependent immunity

    Confirmatory factor analysis of the irrational Performance Beliefs Inventory (iPBI) in a sample of amateur and semi-professional athletes

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    © 2017 Elsevier Ltd Objectives This investigation sought to test the construct validity of the irrational performance beliefs inventory (iPBI) in a sample of amateur and semi-professional athletes. Method In total, 550 athletes (312 men, 212 women, M age = 38.04 ± 13.80 years) completed the iPBI and demographic questions at a single time point. Results Confirmatory factor analysis showed lower than acceptable fit indices for the 28-item iPBI (comparative fit index [CFI] = 0.84). After removal of potential problem items, a 20-item version (iPBI-2) was developed (CFI = 0.91). Results showed that amateur athletes scored higher than semi-professional athletes on primary irrational beliefs and low frustration tolerance, whereas semi-professional athletes scored higher than amateur athletes on depreciation. Conclusions This study provides initial evidence of construct validity for a 20-item version of the iPBI in an athletic sample, and shows medium effect size differences in irrational beliefs between amateur and semi-professional athletes

    Interpreting radiative efficiency in radio-loud AGNs

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    Author submitted version of unrefereed Nature Astronomy comment. Version in journal format available at https://rdcu.be/KH6WRadiative efficiency in radio-loud active galactic nuclei is governed by the accretion rate onto the central black hole rather than directly by the type of accreted matter; while it correlates with real differences in host galaxies and environments, it does not provide unambiguous information about particular objects.Non peer reviewedFinal Accepted Versio

    More positive group memberships are associated with greater resilience in Royal Air Force (RAF) personnel

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    © 2020 The Authors. British Journal of Social Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society In the current project, we examined how perceived group memberships (number, and characteristics, of), social and relational identification, and social identity leadership are associated with resilience in Royal Air Force (RAF) personnel. Based on social identity theorizing, we hypothesized positive associations between the number of groups, perceptions of their characteristics (e.g., positivity), and how they relate to each other (i.e., compatibility) and resilience (H1). We also hypothesized positive associations between both social identity leadership (H2) and resilience, and social and relational identification (H3) and resilience. Two hundred and forty-three personnel from 18 RAF bases completed an identity mapping exercise and measures of leadership, social and relational identification, and resilience. Our findings highlighted the importance of the association between positive group memberships and resilience, and social identification and resilience. Counter to our hypothesis, belonging to more groups was negatively associated with resilience, and there were non-significant relationships between three principles of social identity leadership and resilience, with embedding identity being significantly negatively associated with resilience. In support of social identity theorizing, the number of positive groups was positively associated with resilience, as was social identification. These findings indicate that, for RAF personnel, it is belonging to positive groups, both within and outside work, along with social identification, that is positively associated with resilience

    The Development and Validation of the Thai-Translated Irrational Performance Beliefs Inventory (T-iPBI)

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    © 2018, Springer Science+Business Media, LLC, part of Springer Nature. One of the most commonly employed cognitive-behavioural approaches to psychotherapy is rational-emotive behaviour therapy, but researchers have been troubled by some of the limitations of irrational beliefs psychometrics. As a result, Turner et al. (Eur J Psychol Assess 34:174–180, 2018a. https://doi.org/10.1027/1015-5759/a000314) developed the Irrational Performance Beliefs Inventory (iPBI), a novel measure of irrational beliefs for use within performance domains. However, the linguistic and cross-cultural adaptation of the iPBI into other languages is necessary for its multinational and multicultural use. The purpose of this paper is to develop the Thai-translated version of the iPBI (T-iPBI) and examine the validity and reliability of the T-iPBI. Data retrieved from 166 participants were analysed using SPSS and AMOS software packages. Thirty-three participants completed two follow-up T-iPBI measurements (1- and 3-week repeat assessment). After the linguistic and cross-cultural adaptation processes, the T-iPBI demonstrated excellent levels of reliability, with internal consistency and test–retest reliability, as well as construct, concurrent, and predictive validity. The current findings indicate that the 20-item T-iPBI can be used as a self-assessment instrument to evaluate individual’s irrational performance beliefs in a Thai population. We also highlight the implications of this study and suggest a variety of future research directions that stem from the results

    The Benefits of a Challenge Approach on Match Day: Investigating Cardiovascular Reactivity in Professional Academy Soccer Players.

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    This study assessed physiological (cardiovascular) and psychological (confidence, control, and approach focus) data in professional academy soccer players prior to performance in competitive matches. A challenge state is characterised by an increase in cardiac output (CO), and a decrease in total peripheral vascular resistance (TPR). Data were collected from 37 participants, with 19 of these providing data on two separate occasions. Performance was measured using coach and player self-ratings. Challenge reactivity was positively, and significantly, associated with performance. Participants who demonstrated blunted cardiovascular (CV) responses performed significantly worse than participants who displayed either challenge or threat reactivity. There was mixed consistency in CV reactivity for those participants whose data were collected on more than one occasion, suggesting that some participants responded differently across the competitive matches. The association between self-report data and CV responses was weak. This study supports previous research demonstrating that challenge reactivity is associated with superior performance

    Rational emotive behavior therapy (REBT), irrational and rational beliefs, and the mental health of athletes

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    © 2016 Turner. In this article Rational Emotive Behavior Therapy (REBT) is proposed as a potentially important framework for the understanding and promotion of mental health in athletes. Cognitive-behavioral approaches predominate in the provision of sport psychology, and often form the backbone of psychological skills training for performance enhancement and maintenance. But far from being solely performance-focused, the cognitive-behavioral approach to sport psychology can restore, promote, and maintain mental health. This review article presents REBT (Ellis, 1957), the original cognitive behavioral therapy, as a valuable approach to addressing mental health issues in sport. REBT holds that it is not events that directly cause emotions and behaviors. Rather, it is one's beliefs about the events that lead to emotional and behavioral reactivity. Further, REBT distinguishes between rational and irrational beliefs, and suggests that in response to failure, maltreatment, and misfortune, people can react with either healthy or unhealthy emotional and behavioral responses. The extant research indicates that irrational beliefs lead to unhealthy negative emotions, a range of pathological conditions, and a host of maladaptive behaviors that undermine mental health. Therefore, REBT proposes a process for the reduction of irrational beliefs and the promotion of rational beliefs. The use of REBT in sport is seldom reported in literature, but research is growing. This review article proposes three important areas of investigation that will aid the understanding of irrational beliefs and the application of REBT within sport. These areas are: (1) the influence of irrational beliefs and REBT on the mental health of athletes, (2) the influence of irrational beliefs and REBT on athletic performance, (3) the origins and development of irrational beliefs in athletes. Each area is discussed in turn, offering a critical and progressive review of the literature as well as highlighting research deficits, and recommendations to address each of the three areas of investigation

    Alkylated-C-60 based soft materials: regulation of self-assembly and optoelectronic properties by chain branching

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    Derivatization of fullerene (C60) with branched aliphatic chains softens C60-based materials and enables the formation of thermotropic liquid crystals and room temperature nonvolatile liquids. This work demonstrates that by carefully tuning parameters such as type, number and substituent position of the branched chains, liquid crystalline C60 materials with mesophase temperatures suited for photovoltaic cell fabrication and room temperature nonvolatile liquid fullerenes with tunable viscosity can be obtained. In particular, compound 1, with branched chains, exhibits a smectic liquid crystalline phase extending from 84 °C to room temperature. Analysis of bulk heterojunction (BHJ) organic solar cells with a ca. 100 nm active layer of compound 1 and poly(3-hexylthiophene) (P3HT) as an electron acceptor and an electron donor, respectively, reveals an improved performance (power conversion efficiency, PCE: 1.6 ± 0.1%) in comparison with another compound, 10 (PCE: 0.5 ± 0.1%). The latter, in contrast to 1, carries linear aliphatic chains and thus forms a highly ordered solid lamellar phase at room temperature. The solar cell performance of 1 blended with P3HT approaches that of PCBM/P3HT for the same active layer thickness. This indicates that C60 derivatives bearing branched tails are a promising class of electron acceptors in soft (flexible) photovoltaic devices

    Investigating Irrational Beliefs, Cognitive Appraisals, Challenge and Threat, and Affective States in Golfers Approaching Competitive Situations

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    © Copyright © 2019 Chadha, Turner and Slater. On approach to competitive situations, affective states (emotions and anxiety) occur through the complex interaction of cognitive antecedents. Researchers have intimated that irrational beliefs might play an important role in the relationship between cognitive appraisals and affective states, but has ignored challenge and threat. In the current research, we examine the interaction between cognitive appraisals, irrational beliefs, and challenge and threat to predict golfers’ pre-competitive affective states. We adopted a cross-sectional atemporal design to examine how golfers approached two different competitive situations: imagined imminent golf competition (phase 1), and actual future golf competition (phase 2). Path analysis revealed how cognitive appraisals, irrational beliefs, and challenge and threat interact to predict affective states among golfers. Serial atemporal multiple mediation analysis indicated that the relationships between cognitive appraisals and affective states were mediated by irrational beliefs and challenge and threat. Further, some differences were revealed between phase 1 and phase 2 in the serial multiple atemporal mediation results with regard to challenge. That is, at phase 1 no significant serial mediation was found for any affective outcomes, but at phase 2 significant serial mediation was found for all affective states, showing that irrational beliefs and challenge serial mediated the associations between cognitive appraisals and affective states. The finding that mediation and bivariate associations differed across phase 1 and phase 2 is echoed in the phase 1-phase 2 tests of differences. The current research makes a theoretical advancement by elucidating in more detail the complex interaction between cognitive antecedents and mediators of affective states. Specifically, the inclusion of challenge and threat alongside irrational beliefs and cognitive appraisals is an important theoretical advancement that builds on work inside of sport literature (e.g., Dixon et al., 2016) and outside of sport literature (e.g., David et al., 2002, 2005), as this constellation of theoretically related antecedents of affective states has not been examined together in the extant research
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