Offline Signature Verification by Combining Graph Edit Distance and Triplet Networks

Biometric authentication by means of handwritten signatures is a challenging pattern recognition task, which aims to infer a writer model from only a handful of genuine signatures. In order to make it more difficult for a forger to attack the verification system, a promising strategy is to combine different writer models. In this work, we propose to complement a recent structural approach to offline signature verification based on graph edit distance with a statistical approach based on metric learning with deep neural networks. On the MCYT and GPDS benchmark datasets, we demonstrate that combining the structural and statistical models leads to significant improvements in performance, profiting from their complementary properties

Body mass index and outcome in renal transplant recipients: a systematic review and meta-analysis

BACKGROUND: Whether overweight or obese end stage renal disease (ESRD) patients are suitable for renal transplantation (RT) is often debated. The objective of this review and meta-analysis was to systematically investigate the outcome of low versus high BMI recipients after RT. METHODS: Comprehensive searches were conducted in MEDLINE OvidSP, Web of Science, Google Scholar, Embase, and CENTRAL (the Cochrane Library 2014, issue 8). We reviewed four major guidelines that are available regarding (potential) RT recipients. The methodology was in accordance with the Cochrane Handbook for Systematic Reviews of Interventions and written based on the PRISMA statement. The quality assessment of studies was performed by using the GRADE tool. A meta-analysis was performed using Review Manager 5.3. Random-effects models were used. RESULTS: After identifying 5,526 studies addressing this topic, 56 studies were included. We extracted data for 37 outcome measures (including data of more than 209,000 RT recipients), of which 26 could be meta-analysed. The following outcome measures demonstrated significant differences in favour of low BMI (<30) recipients: mortality (RR = 1.52), delayed graft function (RR = 1.52), acute rejection (RR = 1.17), 1-, 2-, and 3-year graft survival (RR = 0.97, 0.95, and 0.97), 1-, 2-, and 3-year patient survival (RR = 0.99, 0.99, and 0.99), wound infection and dehiscence (RR = 3.13 and 4.85), NODAT (RR = 2.24), length of hospital stay (2.31 days), operation duration (0.77 hours), hypertension (RR = 1.35), and incisional hernia (RR = 2.72). However, patient survival expressed in hazard ratios was in significant favour of high BMI recipients. Differences in other outcome parameters were not significant. CONCLUSIONS: Several of the pooled outcome measurements show significant benefits for ‘low’ BMI (<30) recipients. Therefore, we postulate that ESRD patients with a BMI >30 preferably should lose weight prior to RT. If this cannot be achieved with common measures, in morbidly obese RT candidates, bariatric surgery could be considered. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12916-015-0340-5) contains supplementary material, which is available to authorized users

An interdisciplinary approach to investigate preschool children’s implicit inferential reasoning in scientific activities

The implementation of Science, Technology, Engineering, and Mathematics (STEM) at school is one of the challenges of education in the twenty- first century, especially concerning the development of critical thinking during argumentative interactions. In this paper, I refer to an interdisciplinary approach with the aim to analyze the implicit inferential reasoning emerging in argumentative discussions among children during scientific activities. The study involved 25 preschool children at a kindergarten engaged in three problem solving tasks. The first activity was to build a tunnel, the second to build a bridge—both with the use of Lego©—and the third to build an hourglass with recycled materials. The tasks were video-recorded and the discussions transcribed. The analysis implied different steps: first, I identified the argumentative structure of each exchange according to the pragma-dialectical approach; then, I found the implicit premises using the Argumentum Model of Topics; afterward, I analyzed the argumentative discussions according to a sociocultural approach. The findings show a predominance of arguments based on causal relationships and indicate how children reason regarding complex aspects of a problem, such as the negative consequences of an action, the adequacy of the available tools, and the (possible) future conditions connected to the scientific activity they are involved in. The study opens a possibility to shift from how to implement STEM activities to what children already do when engaged in scientific tasks. It also encourages the adoption of an interdisciplinary approach to investigating the complex process of argumentation in preschool children