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Copyright of Revue de Psychoéducation is the property of La revue canadienne de psycho-education and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue de Psychoéducation is the property of La revue canadienne de psycho-education and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue de Psychoéducation is the property of La revue canadienne de psycho-education and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Taking inspiration from the navigation ability of humans, this study investigated a method of providing robotic controllers with a basic sense of position. It incorporated robotic simulators into robotic controllers to provide themwith amechanismto approximate the effects their actions had on the robot. Controllers with and without internal simulators were tested and compared. The proposed controller architecture was shown to outperformthe regular controller architecture. However, the longer an internal simulator was executed, the more inaccurate it became. Thus, the performance of controllers with internal simulators reduced over time unless their internal simulator was periodically corrected. [ABSTRACT FROM AUTHOR]

SUMMARY: This paper investigates artificial neural network (ANN)-based simulators as an alternative to physics-based approaches for evolving controllers in simulation for a complex snake-like robot. Prior research has been limited to robots or controllers that are relatively simple. Benchmarks are performed in order to identify effective simulator topologies. Additionally, various controller evolution strategies are proposed, investigated and compared. Using ANN-based simulators for controller fitness estimation during controller evolution is demonstrated to be a viable approach for the high-dimensional problem specified in this work. [ABSTRACT FROM AUTHOR]

Copyright of EPPO Bulletin is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Longitudinally extensive transverse myelitis is characteristic but not pathognomonic for neuromyelitis optica spectrum disorders (NMOSDs) and may mimic local tumors. In this retrospective study based on a cohort of 175 NMOSD patients we identified seven patients who initially presented with a longitudinally extensive spinal cord lesion and underwent spinal cord biopsy due to magnetic resonance imaging (MRI)-suspected malignancies. Remarkably, routine neuropathology was inconclusive and did not guide the diagnostic process to anti-aquaporin-4 (AQP4)-seropositive NMOSD. Serious postoperative complications occurred in 5/7 patients and persisted during follow-up in 2/7 patients (29%). Considering these sequelae, AQP4-antibody testing should be mandatory in patients with inconclusive longitudinally extensive spinal cord lesions prior to biopsy. [ABSTRACT FROM PUBLISHER]

Purpose: To prospectively evaluate four non-invasive markers of cartilage quality--T2* mapping, native T1 mapping, dGEMRIC and ΔR1--in healthy volunteers and rheumatoid arthritis (RA) patients.Materials and Methods: Cartilage of metacarpophalangeal (MCP) joints II were imaged in 28 consecutive subjects: 12 healthy volunteers [9 women, mean (SD) age 52.67 (9.75) years, range 30-66] and 16 RA patients with MCP II involvement [12 women, mean (SD) age 58.06 (12.88) years, range 35-76]. Sagittal T2* mapping was performed with a multi-echo gradient-echo on a 3 T MRI scanner. For T1 mapping the dual flip angle method was applied prior to native T1 mapping and 40 min after gadolinium application (delayed gadolinium-enhanced MRI of cartilage, dGEMRIC, T1(Gd)). The difference in the longitudinal relaxation rate induced by gadolinium (ΔR1) was calculated. The area under the receiver operating characteristic curve (AROC) was used to test for differentiation of RA patients from healthy volunteers.Results: dGEMRIC (AUC 0.81) and ΔR1 (AUC 0.75) significantly differentiated RA patients from controls. T2* mapping (AUC 0.66) and native T1 mapping (AUC 0.66) were not significantly different in RA patients compared to controls.Conclusions: The data support the use of dGEMRIC for the assessment of MCP joint cartilage quality in RA. T2* and native T1 mapping are of low diagnostic value. Pre-contrast T1 mapping for the calculation of ΔR1 does not increase the diagnostic value of dGEMRIC. [ABSTRACT FROM AUTHOR]

Copyright of Der Nervenarzt is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Conventional information retrieval models are inappropriate for use in databases containing semi-structured biographical data. A hybrid algorithm that effectively addresses many of the problems in searching biographical databases is presented in this article. An overview of applicable structured text retrieval algorithms is given, with focus specifically on the tree matching model. Small adaptations to the Extended Boolean Model, to make it. more applicable to biographical databases, are described. The adaptation of tree matching models to the hierarchical nature, of data in a person record is described and a distance function between query and record is defined. A hybrid model between the Extended Boolean Model and the adapted Tree Matching Model is then presented. A fast ranking algorithm appropriate for general searches and a more effective (but, more resource intensive) algorithm for more advanced searches is given. It is shown how dates can be incorporated in the hybrid model to create a more powerful search algorithm. The hybrid algorithm can be used to rank records in descending order of relevance to a user's query. [ABSTRACT FROM AUTHOR]

Robotic simulators are often used to speed up the Evolutionary Robotics (ER) process. Most simulation approaches are based on physics modelling. However, physics-based simulators can become complex to develop and require prior knowledge of the robotic system. Robotics simulators can be constructed using Machine Learning techniques, such as Artificial Neural Networks (ANNs). ANN-based simulator development usually requires a lengthy behavioural data collection period before the simulator can be trained and used to evaluate controllers during the ER process. The Bootstrapped Neuro-Simulation (BNS) approach can be used to simultaneously collect behavioural data, train an ANN-based simulator and evolve controllers for a particular robotic problem. This paper investigates proposed improvements to the BNS approach and demonstrates the viability of the approach by optimising gait controllers for a Hexapod and Snake robot platform. • Bootstrapped Neuro-Simulation (BNS) is shown to evolve closed-loop controllers. • Constructs robotic simulators using Artificial Neural Networks and Machine Learning techniques. • Investigates improvements to the BNS approach. • Demonstrates viability of the BNS approach on Hexapod and Snake robot platforms. [ABSTRACT FROM AUTHOR]

Bootstrapped Neuro-Simulation (BNS) is a method of concurrent simulator and robot controller evolution. The algorithm requires little domain knowledge and no pre-investigation data gathering. Additionally, it bridges the reality gap effectively, rapidly evolves functional controllers, and recovers from damage automatically. In this paper, the first evidence of the ability of BNS to evolve closed-loop controllers is shown; in this case to solve a light-following problem. The algorithm is then evaluated for its damage recovery ability for these closed-loop controllers and shown to be very effective, with only minor adaptations. • Bootstrapped Neuro-Simulation is shown to evolve closed-loop controllers. • The algorithm starts in a random state and evolves controllers in minutes. • The algorithm can recover from damage to the robot. • Sliding windows of training data offer the best performance for damage recovery. [ABSTRACT FROM AUTHOR]

It has been nearly 100 years since citrus growers in two distinct regions in the northern provinces of South Africa noticed unusual symptoms in their citrus trees, causing significant crop losses. They had no idea that these symptoms would later become part of an almost global pandemic of a disease called greening or huanglongbing (HLB). The rapid spread of the disease indicated that it might be caused by a transmissible pathogen, but it took >50 years to identify the causative agent as ‘Candidatus Liberibacter africanus’. Recently, the disease appeared in more African countries, spreading by both infected planting material and Trioza erytreae. To date, five ‘Ca. L. africanus’ subspecies have been identified in various rutaceous species, with ‘Ca. L. africanus subsp. clausenae’ the only subspecies for which a biovar was detected in citrus. Efforts to detect and differentiate HLB-causing Liberibacter species are ongoing, and recent developments are discussed here. This review focuses on aspects of the African form of HLB, including its specific bacterial species and subspecies, its main insect vector, its geographic distribution, and current management strategies. [ABSTRACT FROM AUTHOR]

Introduction One of the key symptoms of Parkinson’s disease (PD) is the impairment of spontaneous movement also known as akinesia ( Berardelli et al., 2001 ). Correspondingly, patients performing motor tasks feature abnormal activation in regions such as posterior medial frontal cortex (pMFC) and putamen ( Herz et al., 2013 ). These areas play crucial roles in the internal timing of volitional movements in healthy individuals ( Hoffstaedter et al., 2013 ). Yet, little is known about these regions’ functional connectivity (FC) in PD and its relationship with akinesia. The present study investigated FC alterations of the ’motor initiation network’ in PD, using a seed-based resting-state (RS) analysis. Methods RS fMRI data of 60 patients diagnosed with idiopathic PD (mean age 61.6 ± 10.2; mean disease duration 6.5 ± 5.5 years) and 72 healthy volunteers (mean age 60.1 ± 8.8, matched for age, gender and within-scanner movement) was acquired at two sites. After spatial preprocessing (realignment, normalization, smoothing), temporal filtering was conducted including motion confound removal and band-pass filtering. Seeds in bilateral putamen and pMFC were derived from a meta-analysis on volitional movements ( Hoffstaedter et al., 2014 ). Two more seeds were selected in bilateral primary motor cortex (M1). For each seed, (i) whole-brain FC and (ii) its interaction with akinesia (UPDRS item 3.14) were assessed. RS networks for the aforementioned regions were first mapped in healthy controls only: Contrasting each region’s FC to the FC of all respective other seeds yielded maps of specific connectivity with either seed. These networks were then used to map whole-brain corrected changes of FC in PD. Results were cluster-level corrected for multiple comparisons ( p < 0.05). Results In healthy participants, RS analysis differentiated three networks, specifically (more than all other seeds) connected to bilateral putamen, bilateral M1, and pMFC. In PD, all seeds consistently featured decreased FC with regions in their most related network. That is, M1 mainly showed FC decrease within the M1-related network, pMFC lost FC with anterior insulae and left dorsolateral prefrontal cortex (DLPFC; pMFC-related network), and putamen lost FC with caudate nucleus, pallidum and thalamus (Putamen-related network). Additionally, putamen FC decreased extensively also in those regions more related to M1 and pMFC, including visual, superior parietal, primary somatosensory, M1, pMFC and DLPFC. Testing for each seed’s interaction with akinesia, pMFC showed a decreased FC with inferior parietal lobe (IPL) in the pMFC-related network. In turn, FC of the other seeds did not significantly relate to akinesia. Conclusions The present study examined RS FC changes of bilateral putamen, M1 and pMFC in PD. In patients, putamen FC suggests a marked cortico-striatal decoupling, in line with pathophysiological models of the disease ( Braak et al., 2004 ). In contrast, pMFC featured more selective FC decreases, predominantly in regions involved in motor control ( Hoffstaedter et al., 2013; Hoffstaedter et al., 2014 ). Notably, akinesia was exclusively related to pMFC-connectivity. With increasing impairment, pMFC decoupled from the right IPL. In sum, the present study demonstrates a disruption of cortico-striatal FC and specifies the role of pMFC - IPL connectivity for movement initiation in PD. [ABSTRACT FROM AUTHOR]