2,111 research outputs found

    Cognitive and affective control for adolescents in care versus their peers: implications for mental health

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    Background: Many adolescents who have been removed from the care of their biological parent(s) and placed in State or Local Authority care have experienced significant adversity, including high rates of maltreatment and other trauma(s). As a group, these young people experience far higher rates of mental health difficulties compared to their peers. While their mental health outcomes are well-documented, little is known about mechanisms that may drive this. One potential mechanism, linked to both trauma and adversity exposure and mental health, is affective control (the application of cognitive control in affective contexts). Methods: We compared cognitive and affective control in 71 adolescents (65% girls) in care aged 11–18 (M = 14.82, SD = 2.10) and 71 age and gender-matched peers aged 11–19 years (M = 14.75, SD = 1.95). We measured cognitive and affective control using standard experimental tasks, and for those in care, we also examined associations with self-reported emotion regulation, mental health, and school well-being. Results: After controlling for IQ, there was a significant group difference in affective control performance, with those in care on average performing worse across all tasks. However, further analyses showed this was driven by deficits in overall cognitive control ability, and was not specific to, or worsened by, affective stimuli. Further, we found no evidence that either cognitive or affective control was associated with emotion regulation abilities or the mental health and well-being of young people in care. Conclusions: Results suggest that cognitive and affective control may not underlie mental health for young people in care, though limitations should be considered. We discuss implications for theory and intervention development, and avenues for further research. Trial registration: https://doi.org/10.17605/OSF.IO/QJVD

    Methods for estimating the case fatality ratio for a novel, emerging infectious disease.

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    During the course of an epidemic of a potentially fatal disease, it is important that the case fatality ratio be well estimated. The authors propose a novel method for doing so based on the Kaplan-Meier survival procedure, jointly considering two outcomes (death and recovery), and evaluate its performance by using data from the 2003 epidemic of severe acute respiratory syndrome in Hong Kong, People's Republic of China. They compare this estimate obtained at various points in the epidemic with the case fatality ratio eventually observed; with two commonly quoted, naïve estimates derived from cumulative incidence and mortality statistics at single time points; and with estimates in which a parametric mixture model is used. They demonstrate the importance of patient characteristics regarding outcome by analyzing subgroups defined by age at admission to the hospital

    Multilocus sequence analysis of phylogroup 1 and 2 oral treponeme strains

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    More than 75 ‘species-level' phylotypes of spirochete bacteria belonging to the genus Treponema reside within the human oral cavity. The majority of these oral treponeme phylotypes correspond to as-yet uncultivated taxa, or strains of uncertain standing in taxonomy. Here, we analyze phylogenetic and taxonomic relationships between oral treponeme strains using a multilocus sequence analysis (MLSA) scheme based on the highly-conserved 16S rRNA, pyrH, recA and flaA genes. We utilize this MLSA scheme to analyze genetic data from a curated collection of oral treponeme strains (n=71) of diverse geographical origins. This comprises phylogroup 1 (n=23) and phylogroup 2 (n=48) treponeme strains; including all relevant ATCC reference strains. The taxonomy of all strains was confirmed or inferred via the analysis of ca. 1,450 bp 16S rRNA gene sequences using a combination of bioinformatic and phylogenetic approaches. Taxonomic and phylogenetic relationships between the respective treponeme strains were further investigated by analyzing individual and concatenated flaA (1,074 nt), recA (1,377 nt) and pyrH (696 nt) gene sequence datasets. Our data confirmed the species differentiation between Treponema denticola (n=41) and Treponema putidum (n=7) strains. Notably, our results clearly supported the differentiation of the 23 phylogroup 1 treponeme strains into 5 distinct ‘species-level' phylotypes. These respectively corresponded to ‘Treponema vincentii' (n=11), Treponema medium (n=1); ‘Treponema sinensis' (T. sp. IA; n=4); Treponema sp. IB (n=3); and Treponema sp. IC (n=4). In conclusion, our MLSA-based approach can be used to effectively discriminate oral treponeme taxa, confirm taxonomic assignment, and enable the delineation of species boundaries with high confidence.published_or_final_versio

    Rough paths in idealized financial markets

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    This paper considers possible price paths of a financial security in an idealized market. Its main result is that the variation index of typical price paths is at most 2, in this sense, typical price paths are not rougher than typical paths of Brownian motion. We do not make any stochastic assumptions and only assume that the price path is positive and right-continuous. The qualification "typical" means that there is a trading strategy (constructed explicitly in the proof) that risks only one monetary unit but brings infinite capital when the variation index of the realized price path exceeds 2. The paper also reviews some known results for continuous price paths and lists several open problems.Comment: 21 pages, this version adds (in Appendix C) a reference to new results in the foundations of game-theoretic probability based on Hardin and Taylor's work on hat puzzle

    Comparative analysis of oral treponemes associated with periodontal health and disease

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    Comparative analysis of oral treponemes associated with periodontal health and disease

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    BACKGROUND: Periodontal diseases, such as periodontitis, are chronic inflammatory infections affecting the gingivae (gums), underlying connective tissues and bone that support the teeth. Oral treponemes (genus Treponema) are widely-considered to play important roles in periodontal disease etiology and pathogenesis; however, precise relationships remain to be fully established. METHODS: A 16S rRNA clone library-based approach was used to comprehensively characterize and compare the diversity of treponeme taxa present in subgingival plaque sampled from periodontitis patients (n = 10) versus periodontitis-free controls (n = 10). 16S rRNA gene sequences were assigned to operational taxonomic units (OTUs) using a 99% identity cut-off A variety of taxonomy (OTU) and phylogeny-based statistical approaches were used to compare populations of treponeme OTUs present in both subject groups. RESULTS: A total of 615 plasmid clones containing ca. 1500 bp Treponema 16S rRNA gene sequences were obtained; 365 from periodontitis subjects, 250 from periodontitis-free controls. These were assigned to 110 treponeme OTUs. 93 OTUs were detected in the periodontitis subjects (mean 9.3 ± 5.2 OTUs per subject; range 9–26), and 43 OTUs were detected in controls (mean 4.3 ± 5.9 OTUs per subject; range 3–20). OTUs belonging to oral treponeme phylogroups 1–7 were detected in both subject sets. Phylogroup 1 treponemes had the highest levels of OTU richness (diversity) and clonal abundance within both subject groups. Levels of OTU richness and clonal abundance of phylogroup 2 treponemes were significantly higher in the periodontitis subjects (Mann Whitney U-test, p < 0.001). Both OTU-based and phylogeny-based analyses clearly indicated that there were significant differences in the composition of treponeme communities present in periodontitis versus control subjects. The detection frequency of five OTUs showed a statistically-significant correlation with disease status. The OTU (8P47) that corresponded to the type strain of Treponema denticola had the strongest association with periodontitis (p < 0.01). CONCLUSIONS: Higher levels of treponeme taxon richness and clonal abundance were associated with periodontitis. However, our results clearly indicated that subjects free from clinical symptoms of periodontal disease also contained highly diverse populations of treponeme bacteria within their subgingival microbiota. Our data supports the hypothesis that specific treponeme taxa are associated with periodontal disease

    Complete Genome Sequence for Treponema sp. OMZ 838 (ATCC 700772, DSM 16789), Isolated from a Necrotizing Ulcerative Gingivitis Lesion

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    The oral treponeme bacterium Treponema sp. OMZ 838 was originally isolated from a human necrotizing ulcerative gingivitis (NUG) lesion. Its taxonomic status remains uncertain. The complete genome sequence length was determined to be 2,708,067 bp, with a G+C content of 44.58%, and 2,236 predicted coding DNA sequences (CDS)

    Phylogenetic relationships between Treponema putidum and Treponema denticola isolates

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    Poster Session: Scientific Groups - 88. Microbiology/Immunology II: no. 691OBJECTIVES: To use a multi-gene sequencing approach to characterize genetic diversity within T. putidum strains, to establish their phylogenetic relationships with other species of human and non-human treponemes. METHODS: Sets of primers based on T. denticola gene sequences, were screened for their ability to PCR amplify gene fragments from five T. putidum strains (OMZ 758 (type), 844, 846, 847, 848) as well as several dog and human T. denticola isolates (generously supplied by Dr. Chris Wyss). Individual and concatenated gene sequences were analyzed using various computational evolutionary biology approaches, including Bayesian inference and Maximum Likelihood (ML) ...postprin
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