5,637 research outputs found

    Aberrant brain functional connectivity in newborns with congenital heart disease before cardiac surgery

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    Newborns with congenital heart disease (CHD) requiring open heart surgery are at increased risk for neurodevelopmental disabilities. Recent quantitative MRI studies have reported disrupted growth, microstructure, and metabolism in fetuses and newborns with complex CHD. To date, no study has examined whether functional brain connectivity is altered in this high-risk population after birth, before surgery. Our objective was to compare whole-brain functional connectivity of resting state networks in healthy, term newborns (n = 82) and in term neonates with CHD before surgery (n = 30) using graph theory and network-based statistics. We report for the first time intact global network topology – efficient and economic small world networks – but reduced regional functional connectivity involving critical brain regions (i.e. network hubs and/or rich club nodes) in newborns with CHD before surgery. These findings suggest the presence of early-life brain dysfunction in CHD which may be associated with neurodevelopmental impairments in the years following cardiac surgery. Additional studies are needed to evaluate the prognostic, diagnostic and surveillance potential of these findings

    A Quantile Regression Approach to Measuring the Educational Effect on Body Mass Index

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    Background: By use of a publically available database, the effects of education and geography on obesity as measured by body mass index (BMI) were evaluated with a quantile regression approach. The focus of the analysis was on the practical interpretation of the regression results to inform health policy decision makers about the importance of educational attainment for the growing public health issue of obesity in the US, particularly in the Southeast. Methods: With data from the 2007 Behavioral Risk Factor Surveillance System (BRFSS), quantile regressions were employed to estimate the educational effect on BMI while controlling for relevant lifestyle, socioeconomic, geographic, and demographic factors. Results: The findings indicate that education is important, for college graduates have lower BMIs, regardless of their relative weight distribution. Persons with college educations and annual incomes of more than $50,000 had lower BMIs than those without college education and lower income. Also, after controlling for relevant lifestyle, socioeconomic, and demographic factors such as physical activity, education, and income, regional variations are evident. There are higher BMI levels in the South as compared to other regions in the US. Conclusions: For obesity, there are underlying causes and contributing factors, such as educational attainment and the related factor, income, that are not always considered as high priorities for addressing obesity issues. The focus has typically been on lifestyle choices, such as eating habits and physical activity. The present findings promote efforts for ensuring college education for young people to address various public health issues, including obesity. Further, econometric analysis of secondary databases could lead to a better understanding for policy makers in regard to allocation of resources to address educational attainment, recognizing its effect on public health issues such as obesity

    Visualizing mineralization in deformed opercular bones of larval gilthead sea bream (Sparus aurata)

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    During the rearing process of gilthead sea bream (Sparus aurata), abnormal development of the opercular bone is particularly common (Aquaculture 156, 1997, 165). In order to alleviate its occurrence in rearing facilities, it's crucial to identify the very first physical signs of deviation in normal skeletal development. Nano-CT-scanning was tested for its applicability to quantify deviations in bone mineralization levels. Seven opercles were dissected from larvi of 65 days post hatching, randomly sampled at the commercial sea bream hatchery Maricoltura di Rosignano Solvay (Livorno, Italy). The samples were nano-CT-scanned and computationally reconstructed. Mineralization intensity was colorcoded using Amira software, resulting in a detailed visualization of opercular morphology and mineralization patterns. In conclusion, nano-CT-scanning promises to be a good tool to both describe morphology and detect mineralization levels in the early onset of deformities

    Classification of African ecosystems at 1 km resolution using multiannual SPOT/VEGETATION data and a hybrid clustering approach

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    Ecosystems classification is the process of allocating vegetation types into groups so that individuals in the same class are similar according to their physiological and phonological characteristics to another one. Over large areas, the only suitable technique to obtain frequent and repetitive data acquisitions over such large areas is the use of observations recorded by sensors of moderate resolution. In order to minimize the role of the analyst and to improve the accuracy of the results, innovative and efficient approaches for the classification of ecosystems continue to appear in the literature. This research developed and implemented a new hybrid unsupervised classification approach to derive ecosystems using multi-annual time series by combining hierarchical and partitioning clustering principles. The latter approach is applied on 8-years time series (2000-2007) of 10-day composite Normalized Difference Vegetation Index (NDVI) recorded by SPOT/VEGETATION. After the first segmentation of the mainland in ecoregions using the Fast Fourier Transform (FFT), successive k-nearest neighbor (k-NN) clustering enhance the discrimination of ecosystems and yields to the production of a new ecosystem map for the African continent. The nomenclature relied on the Land Cover Classification System (LCCS) of the Food and Agricultural Organization (FAO). On the basis of validated continental, a pixel-by-pixel analysis is conducted to assess the accuracy of the new classification. The hybrid clustering facilitates the identification/labeling process and the obtained results which should provide key information needed for management/monitoring of natural resources, biodiversity conservation and biogeochemical studies may also deserve vegetation cover modeling at regional and local scal

    Individual cognitive stimulation therapy for dementia : a clinical effectiveness and cost-effectiveness pragmatic, multicentre, randomised controlled trial

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    Background Group cognitive stimulation therapy programmes can benefit cognition and quality of life for people with dementia. Evidence for home-based, carer-led cognitive stimulation interventions is limited. Objectives To evaluate the clinical effectiveness and cost-effectiveness of carer-delivered individual cognitive stimulation therapy (iCST) for people with dementia and their family carers, compared with treatment as usual (TAU). Design A multicentre, single-blind, randomised controlled trial assessing clinical effectiveness and cost-effectiveness. Assessments were at baseline, 13 weeks and 26 weeks (primary end point). Setting Participants were recruited through Memory Clinics and Community Mental Health Teams for older people. Participants A total of 356 caregiving dyads were recruited and 273 completed the trial. Intervention iCST consisted of structured cognitive stimulation sessions for people with dementia, completed up to three times weekly over 25 weeks. Family carers were supported to deliver the sessions at home. Main outcome measures Primary outcomes for the person with dementia were cognition and quality of life. Secondary outcomes included behavioural and psychological symptoms, activities of daily living, depressive symptoms and relationship quality. The primary outcome for the family carers was mental/physical health (Short Form questionnaire-12 items). Health-related quality of life (European Quality of Life-5 Dimensions), mood symptoms, resilience and relationship quality comprised the secondary outcomes. Costs were estimated from health and social care and societal perspectives. Results There were no differences in any of the primary outcomes for people with dementia between intervention and TAU [cognition: mean difference –0.55, 95% confidence interval (CI) –2.00 to 0.90; p-value = 0.45; self-reported quality of life: mean difference –0.02, 95% CI –1.22 to 0.82; p-value = 0.97 at the 6-month follow-up]. iCST did not improve mental/physical health for carers. People with dementia in the iCST group experienced better relationship quality with their carer, but there was no evidence that iCST improved their activities of daily living, depression or behavioural and psychological symptoms. iCST seemed to improve health-related quality of life for carers but did not benefit carers’ resilience or their relationship quality with their relative. Carers conducting more sessions had fewer depressive symptoms. Qualitative data suggested that people with dementia and their carers experienced better communication owing to iCST. Adjusted mean costs were not significantly different between the groups. From the societal perspective, both health gains and cost savings were observed. Conclusions iCST did not improve cognition or quality of life for people with dementia, or carers’ physical and mental health. Costs of the intervention were offset by some reductions in social care and other services. Although there was some evidence of improvement in terms of the caregiving relationship and carers’ health-related quality of life, iCST does not appear to deliver clinical benefits for cognition and quality of life for people with dementia. Most people received fewer than the recommended number of iCST sessions. Further research is needed to ascertain the clinical effectiveness of carer-led cognitive stimulation interventions for people with dementia

    Demographic Variables for Wild Asian Elephants Using Longitudinal Observations

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    Detailed demographic data on wild Asian elephants have been difficult to collect due to habitat characteristics of much of the species’ remaining range. Such data, however, are critical for understanding and modeling population processes in this endangered species. We present data from six years of an ongoing study of Asian elephants (Elephas maximus) in Uda Walawe National Park, Sri Lanka. This relatively undisturbed population numbering over one thousand elephants is individually monitored, providing cohort-based information on mortality and reproduction. Reproduction was seasonal, such that most births occurred during the long inter-monsoon dry season and peaked in May. During the study, the average age at first reproduction was 13.4 years and the 50th percentile inter-birth interval was approximately 6 years. Birth sex ratios did not deviate significantly from parity. Fecundity was relatively stable throughout the observed reproductive life of an individual (ages 11–60), averaging between 0.13–0.17 female offspring per individual per year. Mortalities and injuries based on carcasses and disappearances showed that males were significantly more likely than females to be killed or injured through anthropogenic activity. Overall, however, most observed injuries did not appear to be fatal. This population exhibits higher fecundity and density relative to published estimates on other Asian elephant populations, possibly enhanced by present range constriction. Understanding the factors responsible for these demographic dynamics can shed insight on the future needs of this elephant population, with probable parallels to other populations in similar settings

    Predicting the ecological impacts of an alien invader: experimental approaches reveal the trophic consequences of competition

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    1. Ecological theory on the trophic impacts of invasive fauna on native competitors is equivocal. While increased inter-specific competition can result in coexisting species having constricted and diverged trophic niches, the competing species might instead increase their niche sizes to maintain energy intakes. Empirical experiments can test invasion theory on competitive interactions and niche sizes across different spatial scales and complexity. 2. The consequences of increased inter-specific competition from a model alien fish Leuciscus idus were tested on two taxonomically and trophically similar native fishes, Squalius cephalus and Barbus barbus. Competitive interactions were tested in tank aquaria using comparative functional responses (CFRs) and cohabitation trials. The consequences of these competitive interactions for the trophic niche sizes and positions of the fishes were tested in pond mesocosms. 3. CFRs revealed that compared to B. barbus, L. idus had significantly higher attack and consumption rates; cohabitation trials revealed B. barbus growth rates were depressed in sympatry with L. idus. For L. idus and S. cephalus, differences in their functional response parameters and growth rates were not significant. 4. Pond mesocosms used stable isotope metrics to quantify shifts in the trophic niche sizes of the fishes between allopatry and sympatry using a substitutive experimental design. Isotopic niches were smaller and more divergent in sympatric paired species than predicted by their allopatric treatments, suggesting trophic impacts from inter-specific competition. However, an all-species sympatric treatment revealed similar niche sizes with allopatry. This maintenance of niche sizes in the presence of all species potentially resulted from the buffering of direct competitive effects of the species-pairs by indirect effects. 5. Experimental predictions from tank aquaria assisted the interpretation of the constricted and diverged trophic niches detected in the paired-species sympatric treatments of the pond mesocosms. However, the all-species sympatric treatment of this experiment revealed greater complexity in the outcomes of the competitive interactions within and between the species. These results have important implications for understanding how alien species integrate into food webs and influence the trophic relationships between native species

    NeuralStory: an Interactive Multimedia System for Video Indexing and Re-use

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    In the last years video has been swamping the Internet: websites, social networks, and business multimedia systems are adopting video as the most important form of communication and information. Video are normally accessed as a whole and are not indexed in the visual content. Thus, they are often uploaded as short, manually cut clips with user-provided annotations, keywords and tags for retrieval. In this paper, we propose a prototype multimedia system which addresses these two limitations: it overcomes the need of human intervention in the video setting, thanks to fully deep learning-based solutions, and decomposes the storytelling structure of the video into coherent parts. These parts can be shots, key-frames, scenes and semantically related stories, and are exploited to provide an automatic annotation of the visual content, so that parts of video can be easily retrieved. This also allows a principled re-use of the video itself: users of the platform can indeed produce new storytelling by means of multi-modal presentations, add text and other media, and propose a different visual organization of the content. We present the overall solution, and some experiments on the re-use capability of our platform in edutainment by conducting an extensive user valuation %with students from primary schools

    Realization of Haldane's Exclusion Statistics in a Model of Electron-Phonon Interactions

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    We discuss an integrable model describing one-dimensional electrons interacting with two-dimensional anharmonic phonons. In the low temperature limit it is possible to decouple phonons and consider one-dimensional excitations separately. They have a trivial two-body scattering matrix and obey fractional statistics. As far as we know the original model presents the first example of a model with local bare interactions generating purely statistical interactions between renormalized particles. As a by-product we obtain non-trivial thermodynamic equations for the interacting system of two-dimensional phonons.Comment: 4 page

    Reproducibility of lymphovascular space invasion (LVSI) assessment in endometrial cancer

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    Aims Lymphovascular space invasion (LVSI) in endometrial cancer (EC) is an important prognostic variable impacting on a patient's individual recurrence risk and adjuvant treatment recommendations. Recent work has shown that grading the extent of LVSI further improves its prognostic strength in patients with stage I endometrioid EC. Despite this, there is little information on the reproducibility of LVSI assessment in EC. Therefore, we designed a study to evaluate interobserver agreement in discriminating true LVSI from LVSI mimics (Phase I) and reproducibility of grading extent of LVSI (Phase II). Methods and results Scanned haematoxylin and eosin (H&E) slides of endometrioid EC (EEC) with a predefined possible LVSI focus were hosted on a website and assessed by a panel of six European gynaecological pathologists. In Phase I, 48 H&E slides were included for LVSI assessment and in Phase II, 42 H&E slides for LVSI grading. Each observer was instructed to apply the criteria for LVSI used in daily practice. The degree of agreement was measured using the two-way absolute agreement average-measures intraclass correlation coefficient (ICC). Reproducibility of LVSI assessment (ICC = 0.64, P < 0.001) and LVSI grading (ICC = 0.62, P < 0.001) in EEC was substantial among the observers. Conclusions Given the good reproducibility of LVSI, this study further supports the important role of LVSI in decision algorithms for adjuvant treatment
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