1,046 research outputs found

    Correlates of Disciplinary Practices in Working- to Middle-Class African-American Mothers

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    The disciplinary practices of 52 working- to middle-income African-American mothers were coded to assess the degree to which the mother took a parent-oriented versus a child-oriented approach across various aspects of discipline. Factors associated with physical punishment included maternal education and maternal age. The use of social/material control practices were associated with maternal age, father presence, and concerns about child victimization. Only maternal education was associated with restrictive discipline. Fear of child victimization independently predicted the use of material/social consequences. Findings are discussed in terms of the factors contributing to these individual differences, and the adaptiveness of these practices for the environments in which the parent-child relationship is embedded

    Modeling Local Coherence: An Entity-Based Approach

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    This article proposes a novel framework for representing and measuring local coherence. Central to this approach is the entity-grid representation of discourse, which captures patterns of entity distribution in a text. The algorithm introduced in the article automatically abstracts a text into a set of entity transition sequences and records distributional, syntactic, and referential information about discourse entities. We re-conceptualize coherence assessment as a learning task and show that our entity-based representation is well-suited for ranking-based generation and text classification tasks. Using the proposed representation, we achieve good performance on text ordering, summary coherence evaluation, and readability assessment. 1

    Is plant mitochondrial RNA editing a source of phylogenetic incongruence? An answer from in silico and in vivo data sets

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    <p>Abstract</p> <p>Background</p> <p>In plant mitochondria, the post-transcriptional RNA editing process converts C to U at a number of specific sites of the mRNA sequence and usually restores phylogenetically conserved codons and the encoded amino acid residues. Sites undergoing RNA editing evolve at a higher rate than sites not modified by the process. As a result, editing sites strongly affect the evolution of plant mitochondrial genomes, representing an important source of sequence variability and potentially informative characters.</p> <p>To date no clear and convincing evidence has established whether or not editing sites really affect the topology of reconstructed phylogenetic trees. For this reason, we investigated here the effect of RNA editing on the tree building process of twenty different plant mitochondrial gene sequences and by means of computer simulations.</p> <p>Results</p> <p>Based on our simulation study we suggest that the editing ‘noise’ in tree topology inference is mainly manifested at the cDNA level. In particular, editing sites tend to confuse tree topologies when artificial genomic and cDNA sequences are generated shorter than 500 bp and with an editing percentage higher than 5.0%. Similar results have been also obtained with genuine plant mitochondrial genes. In this latter instance, indeed, the topology incongruence increases when the editing percentage goes up from about 3.0 to 14.0%. However, when the average gene length is higher than 1,000 bp (<it>rps3</it>, <it>matR</it> and <it>atp1</it>) no differences in the comparison between inferred genomic and cDNA topologies could be detected.</p> <p>Conclusions</p> <p>Our findings by the here reported <it>in silico</it> and <it>in vivo</it> computer simulation system seem to strongly suggest that editing sites contribute in the generation of misleading phylogenetic trees if the analyzed mitochondrial gene sequence is highly edited (higher than 3.0%) and reduced in length (shorter than 500 bp).</p> <p>In the current lack of direct experimental evidence the results presented here encourage, thus, the use of genomic mitochondrial rather than cDNA sequences for reconstructing phylogenetic events in land plants.</p

    TRY plant trait database - enhanced coverage and open access

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    Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Determinants of breastfeeding initiation within the first hour of life in a Brazilian population: cross-sectional study

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    <p>Abstract</p> <p>Background</p> <p>Breastfeeding within the first hour of life is a potential mechanism for health promotion. The purpose of this study was to evaluate the prevalence of breastfeeding initiation within the first hour of life in Feira de Santana, Bahia, Brazil, between 2004 and 2005, and investigate the influence of maternal, child and prenatal factors on this practice.</p> <p>Methods</p> <p>This is a cross-sectional study extracted from the results of a contemporary cohort conducted in 10 maternity hospitals in the city of Feira de Santana, Bahia, Brazil. A group of 1,309 mother-child pairs was included in the study. Information about mother's and baby's characteristics, pregnancy, birth, and time of breastfeeding initiation was collected in the first 72 hours after delivery, through interview with mothers and hospital records. The data gathered were stored and analyzed using the SPSS 16.0 and R 8.0. The chi-square test and binary logistic regression analysis were used to examine the relationship between breastfeeding within the first hour and different variables.</p> <p>Results</p> <p>47.1% of the mothers initiated breastfeeding within the first hour after birth. Early initiation of breastfeeding was associated with birth at full term pregnancy (adjusted Prevalence Ratio 1.43; 95% confidence interval 1.10 to 2.00), mothers who received prenatal guidance regarding the advantages of breastfeeding (aPR1.23; 95% CI 1.11 to 1.41) and vaginal delivery (aPR 2.78; 95% CI 2.38 to 3.23).</p> <p>Conclusions</p> <p>In order to improve the rates of breastfeeding within the first hour of life, health care professionals must promote the factors favoring this practice such as prenatal guidance regarding the advantages of breastfeeding, vaginal delivery and full term birth, and stimulate this practice in vulnerable situations such as mothers with cesarean section and preterm birth.</p

    Individuals with Le(a+b−) Blood Group Have Increased Susceptibility to Symptomatic Vibrio cholerae O1 Infection

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    Cholera remains a severe diarrheal disease, capable of causing extensive outbreaks and high mortality. Blood group is one of the genetic factors determining predisposition to disease, including infectious diseases. Expression of different Lewis or ABO blood group types has been shown to be associated with risk of different enteric infections. For example, individuals of blood group O have a higher risk of severe illness due to V. cholerae compared to those with non-blood group O antigens. In this study, we have determined the relationship of the Lewis blood group antigen phenotypes with the risk of symptomatic cholera as well as the severity of disease and immune responses following infection. We show that individuals expressing the Le(a+b−) phenotype were more susceptible to symptomatic cholera, while Le(a–b+) expressing individuals were less susceptible. Individuals with the Le(a–b−) blood group had a longer duration of diarrhea when infected, required more intravenous fluid replacement, and had lower plasma IgA antibody responses to V. cholerae LPS on day 7 following infection. We conclude that there is an association between the Lewis blood group and the risk of cholera, and that this risk may affect the outcome of infection as well as possibly the efficacy of vaccination
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