16,817 research outputs found

    Patterns of Sponge Abundance Across a Gradient of Habitat Quality in the Wakatobi Marine National Park, Indonesia

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    Sponges are important components of reef communities worldwide, fulfilling a number of important functional roles. Habitat degradation caused by the loss of hard corals has the potential to cause increases in sponge abundance and percentage cover as they gain access to resources such as space and food. In this study we compared sponge densities and percentage cover at sites with varying hard coral cover in the Wakatobi Marine National Park, Indonesia (WMNP). We found significant differences in sponge densities at the study sites but no significant difference in sponge densities on different surface angles. Unexpectedly, we also found a weak positive correlation between coral cover and sponge density. This indicates that spatial competition is unlikely to be the most important factor determining sponge abundance in the WMNP. In contrast to sponge density data, we found that sponge percentage cover and hard coral cover were weakly negatively correlated, but found no significant difference in sponge percentage cover between the study sites. Finally, multivariate analysis of the benthic communities at the study sites indicated that while sites with higher coral cover were characterised by coral (proportionally), lower coral cover sites were characterised by algae and sponges. This suggests that although there was no significant difference in sponge percentage cover between the study sites conditions that led to the loss of hard coral at lower quality sites mean that these sites are characterised by sponges and algae rather than by any other groups of benthic organisms

    Development of the parental needs scale for rare diseases : a tool for measuring the supportive care needs of parents caring for a child with a rare disease

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    Background: Children and families affected by rare diseases have received scant consideration from the medical, scientific, and political communities, with parents’ needs especially having received little attention. Affected parents often have limited access to information and support and appropriate health care services. While scales to measure the needs of parents of children with chronic illnesses have been developed, there have been no previous attempts to develop a scale to assess the needs of parents of children with rare diseases. Objective: To develop a scale for measuring the supportive care needs of parents of children with rare diseases. Method: A total of 301 responses to our Parental Needs Survey were randomly divided into two halves, one for exploratory factor analysis and the other for confirmatory factor analysis (CFA). After removing unsuitable items, exploratory factor analysis was undertaken to determine the factor structure of the data. CFA using structural equation modeling was then undertaken to confirm the factor structure. Results: Seventy-two items were entered into the CFA, with a scree plot showing a likely four-factor solution. The results provided four independent subscales of parental needs: Understanding the disease (four items); Working with health professionals (four items); Emotional issues (three items); and Financial needs (three items). The structural equation modeling confirmed the suitability of the four-factor solution and demonstrated that the four subscales could be added to provide an overall scale of parental need. Conclusion: This is the first scale developed to measure the supportive care needs of parents of children with rare diseases. The scale is suitable for use in surveys to develop policy, in individual clinical assessments, and, potentially, for evaluating new programs. Measuring the supportive care needs of parents caring for a child with a rare disease will hopefully lead to better physical and psychological health outcomes for parents and their affected children

    Terrestrial exposure of a fresh Martian meteorite causes rapid changes in hydrogen isotopes and water concentrations

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    Determining the hydrogen isotopic compositions and H2O contents of meteorites and their components is important for addressing key cosmochemical questions about the abundance and source(s) of water in planetary bodies. However, deconvolving the effects of terrestrial contamination from the indigenous hydrogen isotopic compositions of these extraterrestrial materials is not trivial, because chondrites and some achondrites show only small deviations from terrestrial values such that even minor contamination can mask the indigenous values. Here we assess the effects of terrestrial weathering and contamination on the hydrogen isotope ratios and H2O contents of meteoritic minerals through monitored terrestrial weathering of Tissint, a recent Martian fall. Our findings reveal the rapidity with which this weathering affects nominally anhydrous phases in extraterrestrial materials, which illustrates the necessity of sampling the interiors of even relatively fresh meteorite falls and underlines the importance of sample return missions

    A Cluster Analysis of Lifestyle and Health Habits of Youth from Two Geographically and Culturally Diverse Countries

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    Objectives: Obesity is a leading risk factor for global mortality, promoted by poor dietary habits and sedentary behaviour. This study explores the clustering and differences in dietary habits, body mass index (BMI) and physical activity (PA) amongst youth from United Kingdom (UK) and Saudi Arabia (SA). Methods: 2290 males and females aged 15 - 17 years completed a self-report questionnaire and an objective measure of BMI. Results: Youth from SA had a higher prevalence of overweight/obesity and lower levels of PA than youth from the UK. Males were more physically active than females across both countries. Three clusters were identified: a “high risk” cluster with least healthy dietary habits, low PA and high BMI; a “moderate cluster” with moderate healthy dietary habits, PA and BMI; a “low risk” cluster with healthiest dietary habits, greatest PA and the lowest BMI compared to the other clusters. There were more SA youth in the high and moderate risk clusters compared to UK youth. Conclusions: Exploring cross-cultural and demographic characteristics of youth enables the identification of similarities and differences that might lead to the development of universal intervention strategies

    Perception and recognition of faces in adolescence

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    Most studies on the development of face cognition abilities have focussed on childhood, with early maturation accounts contending that face cognition abilities are mature by 3–5 years. Late maturation accounts, in contrast, propose that some aspects of face cognition are not mature until at least 10 years. Here, we measured face memory and face perception, two core face cognition abilities, in 661 participants (397 females) in four age groups (younger adolescents (11.27–13.38 years); mid-adolescents (13.39–15.89 years); older adolescents (15.90–18.00 years); and adults (18.01–33.15 years)) while controlling for differences in general cognitive ability. We showed that both face cognition abilities mature relatively late, at around 16 years, with a female advantage in face memory, but not in face perception, both in adolescence and adulthood. Late maturation in the face perception task was driven mainly by protracted development in identity perception, while gaze perception abilities were already comparatively mature in early adolescence. These improvements in the ability to memorize, recognize and perceive faces during adolescence may be related to increasing exploratory behaviour and exposure to novel faces during this period of life

    A window of opportunity for cognitive training in adolescence

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    In the current study, we investigated windows for enhanced learning of cognitive skills during adolescence. Six hundred thirty-three participants (11–33 years old) were divided into four age groups, and each participant was randomly allocated to one of three training groups. Each training group completed up to 20 days of online training in numerosity discrimination (i.e., discriminating small from large numbers of objects), relational reasoning (i.e., detecting abstract relationships between groups of items), or face perception (i.e., identifying differences in faces). Training yielded some improvement in performance on the numerosity-discrimination task, but only in older adolescents or adults. In contrast, training in relational reasoning improved performance on that task in all age groups, but training benefits were greater for people in late adolescence and adulthood than for people earlier in adolescence. Training did not increase performance on the face-perception task for any age group. Our findings suggest that for certain cognitive skills, training during late adolescence and adulthood yields greater improvement than training earlier in adolescence, which highlights the relevance of this late developmental stage for education

    Change in hematologic indices over time in pediatric inflammatory bowel disease treated with azathioprine

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    Azathioprine leads to changes in mean corpuscular volume (MCV) and white blood cell (WBC) indices reflecting efficacy or toxicity. Understanding the interactions between bone marrow stem cells and azathioprine could highlight abnormal response patterns as forerunners for hematologic malig-nancies. This study gives a statistical description of factors influencing the relationship between MCV and WBC in children with inflammatory bowel disease treated with azathioprine. We found that leukopenia preceded macro¬cytosis. Macrocytosis is therefore not a good predictor of leukopenia. Further studies will be necessary to determine the subgroup of patients at increased risk of malignancies based on bone marrow response

    Discovery of mating in the major African livestock pathogen Trypanosoma congolense

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    The protozoan parasite, Trypanosoma congolense, is one of the most economically important pathogens of livestock in Africa and, through its impact on cattle health and productivity, has a significant effect on human health and well being. Despite the importance of this parasite our knowledge of some of the fundamental biological processes is limited. For example, it is unknown whether mating takes place. In this paper we have taken a population genetics based approach to address this question. The availability of genome sequence of the parasite allowed us to identify polymorphic microsatellite markers, which were used to genotype T. congolense isolates from livestock in a discrete geographical area of The Gambia. The data showed a high level of diversity with a large number of distinct genotypes, but a deficit in heterozygotes. Further analysis identified cryptic genetic subdivision into four sub-populations. In one of these, parasite genotypic diversity could only be explained by the occurrence of frequent mating in T. congolense. These data are completely inconsistent with previous suggestions that the parasite expands asexually in the absence of mating. The discovery of mating in this species of trypanosome has significant consequences for the spread of critical traits, such as drug resistance, as well as for fundamental aspects of the biology and epidemiology of this neglected but economically important pathogen
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