A new approach to optimise Non-Binary LDPC codes for Coded Modulations

International audienceThis paper is dedicated to the optimisation of Non-Binary LDPC codes when associated to high-order modulations. To be specific, we propose to specify the values of the non-zero NB-LDPC parity matrix coefficients depending on the corresponding check node equation and the Euclidean distance of the coded modulation. In other words, we explore the joint optimisation of the modulation mapping and the non-binary matrix. The performance gains announced by a theoretical analysis based on the Union Bound are confirmed by simulations results. We obtain an 0.2-dB gain in the high SNR regime compared to other state-of-the-art matrices

How does a chronic wound change a patient's social life?:A European survey on social support and social participation

Chronic wounds can severely limit patient's social life. This cross-sectional study investigated quantitatively social support of patients with chronic wounds, its association with health-related quality of life as well as qualitatively changes in social participation of these patients. Overall, 263 patients from seven countries participated. The most frequent wound class was leg ulcer (49.2%). Results revealed generally high levels of social support (mean global score: 5.5) as measured with the Multidimensional Scale of Perceived Social Support. However, individuals differed considerably (range 1.0–7.0). All dimensions of social support differed by patients' family and living situations (p &lt; 0.001 to p = 0.040) and were positively correlated with generic health-related quality of life (r = 0.136–0.172). Having children, living with others and being in a relationship were significant predictors of having higher global social support. Patients reported great support from family members. Many participants reported no changes in relationships with friends. Wound care managers took an important role and provided additional emotional support. Patients reported a range of discontinued activities. Despite the high overall level of social support, inter-individual differences should be acknowledged. The importance of family carers should be acknowledged to be able to reduce caregiver burden and to ensure high-qualitative wound care.</p

How does a chronic wound change a patient's social life? A European survey on social support and social participation

Chronic wounds can severely limit patient's social life. This cross-sectional study investigated quantitatively social support of patients with chronic wounds, its association with health-related quality of life as well as qualitatively changes in social participation of these patients. Overall, 263 patients from seven countries participated. The most frequent wound class was leg ulcer (49.2%). Results revealed generally high levels of social support (mean global score: 5.5) as measured with the Multidimensional Scale of Perceived Social Support. However, individuals differed considerably (range 1.0–7.0). All dimensions of social support differed by patients' family and living situations (p &lt; 0.001 to p = 0.040) and were positively correlated with generic health-related quality of life (r = 0.136–0.172). Having children, living with others and being in a relationship were significant predictors of having higher global social support. Patients reported great support from family members. Many participants reported no changes in relationships with friends. Wound care managers took an important role and provided additional emotional support. Patients reported a range of discontinued activities. Despite the high overall level of social support, inter-individual differences should be acknowledged. The importance of family carers should be acknowledged to be able to reduce caregiver burden and to ensure high-qualitative wound care.</p

Validation of the Wound-QoL-17 and the Wound-QoL-14 in a European sample of 305 patients with chronic wounds

The Wound-QoL assesses the impact of chronic wounds on patients' health-related quality of life (HRQoL). A 17-item and a shortened 14-item version are available. The Wound-QoL-17 has been validated for multiple languages. For the Wound-QoL-14, psychometric properties beyond internal consistency were lacking. We aimed to validate both Wound-QoL versions for international samples representing a broad range of European countries, including countries for which validation data had yet been pending. Patients with chronic wounds of any aetiology or location were recruited in Austria, Lithuania, the Netherlands, Poland, Slovakia, Spain, Switzerland and Ukraine. Psychometric properties were determined for both Wound-QoL versions for the overall sample and, if feasible, country-wise. We included 305 patients (age 68.5 years; 52.8% males). Internal consistency was high in both Wound-QoL-17 (Cronbach's α: 0.820–0.933) and Wound-QoL-14 (0.779–0.925). Test–retest reliability was moderate to good (intraclass correlation coefficient: 0.618–0.808). For Wound-QoL-17 and Wound-QoL-14, convergent validity analyses showed highest correlations with global HRQoL rating (r = 0.765; r = 0.751) and DLQI total score (r = 0.684; r = 0.681). Regarding clinical data, correlations were largest with odour (r = −0.371; r = −0.388) and wound size (r = 0.381; r = 0.383). Country-wise results were similar. Both Wound-QoL versions are valid to assess HRQoL of patients with chronic wounds. Due to its psychometric properties and brevity, the Wound-QoL-14 might be preferrable in clinical practice where time is rare. The availability of various language versions allows for the use of this questionnaire in international studies and in clinical practice when foreign language patients are being treated.</p

Validation of the Wound-QoL-17 and the Wound-QoL-14 in a European sample of 305 patients with chronic wounds

The Wound-QoL assesses the impact of chronic wounds on patients' health-related quality of life (HRQoL). A 17-item and a shortened 14-item version are available. The Wound-QoL-17 has been validated for multiple languages. For the Wound-QoL-14, psychometric properties beyond internal consistency were lacking. We aimed to validate both Wound-QoL versions for international samples representing a broad range of European countries, including countries for which validation data had yet been pending. Patients with chronic wounds of any aetiology or location were recruited in Austria, Lithuania, the Netherlands, Poland, Slovakia, Spain, Switzerland and Ukraine. Psychometric properties were determined for both Wound-QoL versions for the overall sample and, if feasible, country-wise. We included 305 patients (age 68.5 years; 52.8% males). Internal consistency was high in both Wound-QoL-17 (Cronbach's α: 0.820–0.933) and Wound-QoL-14 (0.779–0.925). Test–retest reliability was moderate to good (intraclass correlation coefficient: 0.618–0.808). For Wound-QoL-17 and Wound-QoL-14, convergent validity analyses showed highest correlations with global HRQoL rating (r = 0.765; r = 0.751) and DLQI total score (r = 0.684; r = 0.681). Regarding clinical data, correlations were largest with odour (r = −0.371; r = −0.388) and wound size (r = 0.381; r = 0.383). Country-wise results were similar. Both Wound-QoL versions are valid to assess HRQoL of patients with chronic wounds. Due to its psychometric properties and brevity, the Wound-QoL-14 might be preferrable in clinical practice where time is rare. The availability of various language versions allows for the use of this questionnaire in international studies and in clinical practice when foreign language patients are being treated.</p

Demographic modeling with whole genome data reveals parallel origin of similar Pundamilia cichlid species after hybridization

Modes and mechanisms of speciation are best studied in young species pairs. In older taxa it is increasingly difficult to distinguish what happened during speciation from what happened after speciation. Lake Victoria cichlids in the genus Pundamilia encompass a complex of young species and polymorphic populations. One Pundamilia species pair, P. pundamilia and P. nyererei, is particularly well-suited to study speciation because sympatric population pairs occur with different levels of phenotypic differentiation and reproductive isolation at different rocky islands within the lake. Genetic distances between allopatric island populations of the same nominal species often exceed those between the sympatric species. It thus remained unresolved whether speciation into P. nyererei and P. pundamilia occurred once, followed by geographical range expansion and interspecific gene flow in local sympatry, or if the species pair arose repeatedly by parallel speciation. Here we use genomic data and demographic modeling to test these alternative evolutionary scenarios. We demonstrate that gene flow plays a strong role in shaping the observed patterns of genetic similarity, including both gene flow between sympatric species and gene flow between allopatric populations, as well as recent and early gene flow. The best supported model for the origin of P. pundamilia and P. nyererei population pairs at two different islands is one where speciation happened twice, whereby the second speciation event follows shortly after introgression from an allopatric P. nyererei population that arose earlier. Our findings support the hypothesis that very similar species may arise repeatedly, potentially facilitated by introgressed genetic variation

Open Science principles for accelerating trait-based science across the Tree of Life.

Synthesizing trait observations and knowledge across the Tree of Life remains a grand challenge for biodiversity science. Species traits are widely used in ecological and evolutionary science, and new data and methods have proliferated rapidly. Yet accessing and integrating disparate data sources remains a considerable challenge, slowing progress toward a global synthesis to integrate trait data across organisms. Trait science needs a vision for achieving global integration across all organisms. Here, we outline how the adoption of key Open Science principles-open data, open source and open methods-is transforming trait science, increasing transparency, democratizing access and accelerating global synthesis. To enhance widespread adoption of these principles, we introduce the Open Traits Network (OTN), a global, decentralized community welcoming all researchers and institutions pursuing the collaborative goal of standardizing and integrating trait data across organisms. We demonstrate how adherence to Open Science principles is key to the OTN community and outline five activities that can accelerate the synthesis of trait data across the Tree of Life, thereby facilitating rapid advances to address scientific inquiries and environmental issues. Lessons learned along the path to a global synthesis of trait data will provide a framework for addressing similarly complex data science and informatics challenges

Amniotic fluid embolism incidence, risk factors and outcomes: a review and recommendations

<p>Abstract</p> <p>Background</p> <p>Amniotic fluid embolism (AFE) is a rare but severe complication of pregnancy. A recent systematic review highlighted apparent differences in the incidence, with studies estimating the incidence of AFE to be more than three times higher in North America than Europe. The aim of this study was to examine population-based regional or national data from five high-resource countries in order to investigate incidence, risk factors and outcomes of AFE and to investigate whether any variation identified could be ascribed to methodological differences between the studies.</p> <p>Methods</p> <p>We reviewed available data sources on the incidence of AFE in Australia, Canada, the Netherlands, the United Kingdom and the USA. Where information was available, the risk factors and outcomes of AFE were examined.</p> <p>Results</p> <p>The reported incidence of AFE ranged from 1.9 cases per 100 000 maternities (UK) to 6.1 per 100 000 maternities (Australia). There was a clear distinction between rates estimated using different methodologies. The lowest estimated incidence rates were obtained through validated case identification (range 1.9-2.5 cases per 100 000 maternities); rates obtained from retrospective analysis of population discharge databases were significantly higher (range 5.5-6.1 per 100 000 admissions with delivery diagnosis). Older maternal age and induction of labour were consistently associated with AFE.</p> <p>Conclusions</p> <p>Recommendation 1: Comparisons of AFE incidence estimates should be restricted to studies using similar methodology. The recommended approaches would be either population-based database studies using additional criteria to exclude false positive cases, or tailored data collection using existing specific population-based systems.</p> <p>Recommendation 2: Comparisons of AFE incidence between and within countries would be facilitated by development of an agreed case definition and an agreed set of criteria to minimise inclusion of false positive cases for database studies.</p> <p>Recommendation 3: Groups conducting detailed population-based studies on AFE should develop an agreed strategy to allow combined analysis of data obtained using consistent methodologies in order to identify potentially modifiable risk factors.</p> <p>Recommendation 4: Future specific studies on AFE should aim to collect information on management and longer-term outcomes for both mothers and infants in order to guide best practice, counselling and service planning.</p

GISCOME – Genetics of Ischaemic Stroke Functional Outcome network: A protocol for an international multicentre genetic association study

© 2017, © European Stroke Organisation 2017. Introduction: Genome-wide association studies have identified several novel genetic loci associated with stroke risk, but how genetic factors influence stroke outcome is less studied. The Genetics of Ischaemic Stroke Functional outcome network aims at performing genetic studies of stroke outcome. We here describe the study protocol and methods basis of Genetics of Ischaemic Stroke Functional outcome. Methods: The Genetics of Ischaemic Stroke Functional outcome network has assembled patients from 12 ischaemic stroke projects with genome-wide genotypic and outcome data from the International Stroke Genetics Consortium and the National Institute of Neurological Diseases Stroke Genetics Network initiatives. We have assessed the availability of baseline variables, outcome metrics and time-points for collection of outcome data. Results: We have collected 8831 ischaemic stroke cases with genotypic and outcome data. Modified Rankin score was the outcome metric most readily available. We detected heterogeneity between cohorts for age and initial stroke severity (according to the NIH Stroke Scale), and will take this into account in analyses. We intend to conduct a first phase genome-wide association outcome study on ischaemic stroke cases with data on initial stroke severity and modified Rankin score within 60–190 days. To date, we have assembled 5762 such cases and are currently seeking additional cases meeting these criteria for second phase analyses. Conclusion: Genetics of Ischaemic Stroke Functional outcome is a unique collection of ischaemic stroke cases with detailed genetic and outcome data providing an opportunity for discovery of genetic loci influencing functional outcome. Genetics of Ischaemic Stroke Functional outcome will serve as an exploratory study where the results as well as the methodological observations will provide a basis for future studies on functional outcome. Genetics of Ischaemic Stroke Functional outcome can also be used for candidate gene replication or assessing stroke outcome non-genetic association hypotheses