27 research outputs found

    Improved Parkinson’s disease classification from diffusion MRI data by Fisher vector descriptors

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    Due to the complex clinical picture of Parkinson’s disease (PD), the reliable diagnosis of patients is still challenging. A promising approach is the structural characterization of brain areas affected in PD by diffusion magnetic resonance imaging (dMRI). Standard classification methods depend on an accurate non-linear alignment of all images to a common reference template, and are challenged by the resulting huge dimensionality of the extracted feature space. Here, we propose a novel diagnosis pipeline based on the Fisher vector algorithm. This technique allows for a precise encoding into a high-level descriptor of standard diffusion measures like the fractional anisotropy and the mean diffusivity, extracted from the regions of interest (ROIs) typically involved in PD. The obtained low dimensional, fixed-length descriptors are independent of the image alignment and boost the linear separability of the problem in the description space, leading to more efficient and accurate diagnosis. In a test cohort of 50 PD patients and 50 controls, the implemented methodology outperforms previous methods when using a logistic linear regressor for classification of each ROI independently, which are subsequently combined into a single classification decision

    The COMPARE Data Hubs

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    Data sharing enables research communities to exchange findings and build upon the knowledge that arises from their discoveries. Areas of public and animal health as well as food safety would benefit from rapid data sharing when it comes to emergencies. However, ethical, regulatory and institutional challenges, as well as lack of suitable platforms which provide an infrastructure for data sharing in structured formats, often lead to data not being shared or at most shared in form of supplementary materials in journal publications. Here, we describe an informatics platform that includes workflows for structured data storage, managing and pre-publication sharing of pathogen sequencing data and its analysis interpretations with relevant stakeholders

    Irish cardiac society - Proceedings of annual general meeting held 20th & 21st November 1992 in Dublin Castle

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases. To worsen this situation, human-induced modifications may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge, it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Pathways of Legal Advocacy for Change: Ethiopian Women Lawyers Association

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    Changing the legal environment can have transformative impacts on the lives of the most vulnerable. However, little is known about how legal advocacy can effectively achieve this within contexts where governments are not receptive to advocacy of this nature. This article outlines the activities of the Ethiopian Women Lawyers Association (EWLA) as it played a focal role in changing the Family Law, making important progress to removing aspects of the law that discriminated against women. We outline the ‘pathway’ of change taken by the organization, which moved from service provision to building an evidence-based, formal and informal advocacy, and finally utilizing critical junctures to encourage change to the law. This article also highlights the important role of enabling environments, as after several successful efforts of legal advocacy, the government closed down the operational space for legal advocacy, effectively stifling continued, or any new forms of, legal advocacy. This article provides insight on successful approaches to legal advocacy in challenging governance contexts as well as the limitations and opportunities that external actors can have

    Arterial switch with full-flow cardiopulmonary bypass and limited circulatory arrest: Neurodevelopmental outcome

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    AbstractObjectivesNeonatal cardiac surgery has been associated with unfavorable neurodevelopmental events. We investigated a patient cohort operated on predominantly with full-flow cardiopulmonary bypass (150 mL · kg−1 · min−1, α-stat, α-blockade, median arrest = 6 minutes, temperature of 22°C) as the major support strategy for neonatal arterial switch operations (transposition of the great arteries and intact ventricular septum).MethodsSeventy-four patients and “best-friend” control subjects were assessed 109 months (range, 48-166 months) postoperatively with general medical and neurologic evaluation, IQ testing, formal movement scores, and detailed parent-teacher behavioral-social reports. Fetal, neonatal, and perioperative data were collated.ResultsThe prevalence of perioperative seizures was 6.8% (4/5 cases occurring preoperatively). The incidence of all perioperative neurologic abnormalities was 20%. Patients who had a neurologic event were (as a group) older at the time of operation and had a lower arterial blood pH before the operation. Selected perioperative factors (not related directly to cardiopulmonary bypass variables) predicted early (before discharge) neurologic outcome in a multivariate model. At late assessment, patients were more likely than control subjects to have a mild neurologic abnormality (P = 0.002). Full-scale IQ scores (Wechsler Preschool and Primary Scale of Intelligence and Wechsler Intelligence Scale for Children—Third Edition) were higher in control subjects (101.9 [SD = 13] vs 108.6 [SD = 12], P = .0007), with both groups having scores greater than the population-based test means. Full-scale IQ scores related most significantly to years of paternal education (β = 1.51, P = .0078) but were also influenced by perioperative neurologic abnormalities, birth weight, and circulatory arrest time. Patients had higher motor impairment scores (Movement Assessment Battery) than control subjects (P = .0004). Parents (Achenbach Child Development Checklist) assigned higher total social-behavioral competence scores to control subjects (P = .05). Teachers (Achenbach Teacher Report Form) suggested that patients were more likely to be perceived as having various speech and expressive language problems, as well as minor behavioral problems.ConclusionWith the perioperative strategies used, not all survivors can be considered (neurodevelopmentally) normal at late follow-up, although the risk of important impairment is low. Perioperative events might have long-term prognostic value. On the basis of this study and published data regarding other strategies, continued application of full-flow cardiopulmonary bypass is justified, with the proviso that further investigation is required

    Post-fire flowering and fruiting in Vellozia sincorana, a caulescent rosette plant endemic to Northeast Brazil

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    Vellozia sincorana L.B. Sm. & Ayensu, an endemic of campos rupestres, is an endangered species collected by local people to start cooking fires due to the flammability of its resinous stems. A massive flowering of V. sincorana following a wildfire in October 1999 raised some questions: Does fire affect flowering and fruiting of V. sincorana? Is the height of individuals correlated with flowering and fruit production? A wildfire event on 8 November 2008 provided an opportunity to explore these questions. Two populations of V. sincorana in two campos rupestres sites (12º31'S - 41º29'W; 12º36'S - 41º28'W) on ridgetops in the Chapada Diamantina National Park (Brazil) were monitored, one burned in the November 2008 fire and the other unburned since the 1999 fire. In both sites, 25 individuals were randomly labeled and monitored. Nine plant samplings were conducted between 2008 and 2010, during which the number of flowers and fruits were tallied and the heights measured. Spearman's rank correlation coefficient and linear regression were used to evaluate the relationship between the height of individuals and phenology. Flowering and fruiting occurred only in the recently burnt population, about 40 days after the fire, in 24 of the 25 individuals monitored (96%). The quantity of flower and/or fruit was positively and significantly correlated with plant height. The abundant flowering after fire suggests that fire triggers this phenological phase. Estimates of age of the taller individuals and the periods of flowering can be used to estimate fire frequency in the V. sincorana population sites, which contributes to the knowledge of fire ecology and is useful for conservation biology and fire management of campos rupestres
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