5,746 research outputs found

    A numerical study of forced lithospheric thinning

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    Subsolidus lithospheric thinning by mantle plumes may be involved in the creation of swells, hotspots, and rifts. Among the major questions concerning this process are the timescale on which it occurs and the structure of the plumes. The lithosphere is known to have been substantially thinned in 10 Ma or less. Current studies are focused on the lithospheric thinning by time-dependent plumes hypothesized to have large temperature differences across them

    Cardiac manifestations of PRKAG2 mutation.

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    BACKGROUND:The Protein Kinase AMP-Activated Non-Catalytic Subunit Gamma 2 (PRKAG2) cardiac syndrome is characterized by glycogen accumulation in the cardiac tissue. The disease presents clinically with hypertrophic cardiomyopathy (HCM), and it is often associated with conduction abnormalities. CASE PRESENTATION:A 23 year-old female with history of Wolff-Parkinson-White (WPW) and HCM presented for evaluation after an episode of Non-ST Elevation Myocardial Infarction (NSTEMI). The patient was found to have severe coronary bridging on angiography and underwent an unroofing of the left anterior descending artery (LAD). Due to the constellation of symptoms, the patient underwent genetic testing and a cardiac muscle biopsy. Genetic testing was significant for an Arg302Gln mutation in the PRKAG2 gene. Cardiac tissue biopsy revealed significant myocyte hypertrophy and large vacuoles with glycogen stores. CONCLUSION:The pathologic and genetics findings of our patient are consistent with PRKAG2 syndrome. Patients presenting with conduction abnormalities and suspected HCM should be considered for genetic testing to identify possible underlying genetic etiologies

    Blurring the boundaries between synthesis and evaluation. A customized realist evaluative synthesis into adolescent risk behavior prevention

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    Realist methodologies have been increasingly advocated for the investigation of complex social issues. Public health programs, such as those designed to prevent adolescent risk behavior, are typically considered complex. In conducting a realist review of the empirical literature relating to such programs, we encountered several challenges, including (a) an overabundance of empirical evidence, (b) a problematic level of heterogeneity within and between methodological approaches, (c) discrepancies between theoretical underpinnings and program operationalization, (d) homogeneity of program outcomes, with very little variation in program effectiveness, and (d) a paucity of description relating to content and process. To overcome these challenges, we developed a customized approach to realist evidence synthesis, drawing on the VICTORE (Volition, Implementation, Contexts, Time, Outcomes, Rivalry, and Emergence) complexity checklist and incorporating stakeholder engagement as primary data to achieve greater depth of understanding relating to contextual and mechanistic factors, and the complex interactions between them. Here we discuss the benefits of this adapted methodology alongside an overview of the research through which the methodology was developed. A key finding from this research was that combining the complexity checklist with primary data from stakeholder engagement enabled us to systematically interrogate the data across data sources, uncovering and evidencing mechanisms which may otherwise have remained hidden, giving greater ontological depth to our research findings. This paper builds on key methodological developments in realist research, demonstrating how realist methodologies can be customized to overcome challenges in developing and refining program theory from the literature, and contributes to the broader literature of innovative approaches to realist research

    Phylogenetic escalation and decline of plant defense strategies

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    As the basal resource in most food webs, plants have evolved myriad strategies to battle consumption by herbivores. Over the past 50 years, plant defense theories have been formulated to explain the remarkable variation in abundance, distribution, and diversity of secondary chemistry and other defensive traits. For example, classic theories of enemy-driven evolutionary dynamics have hypothesized that defensive traits escalate through the diversification process. Despite the fact that macroevolutionary patterns are an explicit part of defense theories, phylogenetic analyses have not been previously attempted to disentangle specific predictions concerning (i) investment in resistance traits, (ii) recovery after damage, and (iii) plant growth rate. We constructed a molecular phylogeny of 38 species of milkweed and tested four major predictions of defense theory using maximum-likelihood methods. We did not find support for the growth-rate hypothesis. Our key finding was a pattern of phyletic decline in the three most potent resistance traits (cardenolides, latex, and trichomes) and an escalation of regrowth ability. Our neontological approach complements more common paleontological approaches to discover directional trends in the evolution of life and points to the importance of natural enemies in the macroevolution of species. The finding of macroevolutionary escalating regowth ability and declining resistance provides a window into the ongoing coevolutionary dynamics between plants and herbivores and suggests a revision of classic plant defense theory. Where plants are primarily consumed by specialist herbivores, regrowth (or tolerance) may be favored over resistance traits during the diversification processThis work was supported by the National Science Foundation

    An Anti-C1s Monoclonal, TNT003, Inhibits Complement Activation Induced by Antibodies Against HLA.

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    Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab')2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro

    The identification of salient beliefs concerning university students’ decision to participate in sport

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    The aim of this study was to identify salient beliefs toward university-provided recreational sport in first-year undergraduate students. A purposive sample of 76 students (36 males, 40 females; mean age: 19.2 ± 1.7 years) undertaking various degree subjects at a higher education institution in the North of England, United Kingdom, was used in the study. The instrument was a theory-based open-ended questionnaire informed by the Theory of Planned Behavior, addressing behavioral, normative, and control beliefs. Thematic content analysis and coding was conducted on 30 randomly selected questionnaires followed by a frequency count to identify the modal salient beliefs. The modal set revealed 17 beliefs from a possible 53: six behavioral, five normative, and six control. These beliefs were related to health benefits, enjoyment, friendships, time constraints, study workloads, awareness, and the perception of family, friends, and academics. The results highlight the factors that should be targeted for intervention and provide data to be utilized for a second main quantitative study which will identify more specific belief targets. Due to equivocal intervention success, this formative research can serve to help increase the number of students participating in university recreational spor

    The role of brand loyalty and social media in e-commerce interfaces: survey results and implications for user interfaces

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    This paper explores the role of brand loyalty and social media in e-commerce interfaces. A survey consisting of 118 respondents was contacted to address the questions relating to online shopping and brand loyalty. Link between the frequency of access and time spent on an e-commerce user interface, and brand loyalty, gender and age profile differences, and the role of social media to branding and on-line shopping was analyzed. It was found that online loyalty differs from offline loyalty and loyalty also differed across genders, showing men were more loyal than women when shopping online. Information shared about products on social media by friends and family played an important role in purchase decision making. Website interface and ease of navigation were also key aspects for online shopping. The research concluded with recommendations to create multimodal websites which are more interactive and targeted so customer experience is enhanced and loyalty is achieved through the use of interactivity and social media

    Antimicrobial resistance: a biopsychosocial problem requiring innovative interdisciplinary and imaginative interventions

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    To date, antimicrobials have been understood through largely biomedical perspectives. There has been a tendency to focus upon the effectiveness of pharmaceuticals within individual bodies. However, the growing threat of antimicrobial resistance demands we reconsider how we think about antimicrobials and their effects. Rather than understanding them primarily within bodies, it is increasingly important to consider their effects between bodies, between species and across environments. We need to reduce the drivers of antimicrobial resistance (AMR) at a global level, focusing on the connections between prescribing in one country and resistance mechanisms in another. We need to engage with the ways antimicrobials within the food chain will impact upon human healthcare. Moreover, we need to realise what happens within the ward will impact upon the environment (through waste water). In the future, imaginative interventions will be required that must make the most of biomedicine but draw equally across a wider range of disciplines (e.g. engineering, ecologists) and include an ever-increasing set of professionals (e.g. nurses, veterinarians and farmers). Such collective action demands a shift to working in new interdisciplinary, inter-professional ways. Mutual respect and understanding is required to enable each perspective to be combined to yield synergistic effects

    Comparative analysis between condom use clusters and risk behaviours among portuguese university students

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    The research on condom use has been focused on high-risk individuals, paying less attention to those who have moderate risk or safe sexual conducts. In order to design accurate interventions, potential differences among the condom use behavior groups must be considered. The goal was to assess possible differences in individuals presenting different types of risk behavior. 140 heterosexual university students answered a self-reported questionnaire about their sexual history, condom use habits, sexual self-esteem, sexual satisfaction, sexual control, attitudes towards condoms, self-efficacy to condom use, and emotions and feelings during sexual intercourse. A cluster analysis was conducted using the results about condom use and risk behaviors. Three groups with different risk levels emerged, presenting differences over sexual self-efficacy, attitudes towards condoms, socio-demographic variables, and sexual history. The results suggest the condom use inconsistency is highly associated with other risk behaviors but the contrary does not necessarily happens. Condom use consistent users also presented risk behaviors as smoking and drinking. The group differences suggest the risks were more affected by the combination of lack of skills with a negative attitude toward condoms than by contextual or personal variables. These differences sustain the need of an intervention adjusted to the individual's risk levels, since they differ on skills and beliefs that may hinder or promote the adoption of health behaviors.Foundation for Science and Technology/Fundacao para a Ciencia e Tecnologia (Portugal)info:eu-repo/semantics/publishedVersio
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