2,648 research outputs found

    Attentional processes during P3-based Brain Computer Interface task in amyotrophic lateral sclerosis patients

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    To be available for a wide range of end-users a brain-computer interface (BCI) should be flexible and adaptable to end-users’ cognitive strengths and weaknesses. People’s cognitive abilities change according to the disease they are affected by, and people suffering from the same disease could have different cognitive capacities. We aimed at investigating how the amyotrophic lateral sclerosis (ALS) disease, and two different cognitive attentional aspects [1] influenced the usage of a P3-based BC

    Towards a Powerful Hardware‐in‐the‐Loop System for Virtual Calibration of an Off‐Road Diesel Engine

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    A common challenge among internal combustion engine (ICE) manufacturers is shorten-ing the development time while facing requirements and specifications that are becoming more complex and border in scope. Virtual simulation and calibration are effective instruments in the face of these demands. This article presents the development of zero‐dimensional (0D)—real‐time engine and exhaust after‐treatment system (EAS) models and their deployment on a Virtual test bench (VTB). The models are created using a series of measurements acquired in a real test bench, carefully performed in view of ensuring the highest reliability of the models themselves. A zero‐dimensional approach was chosen to guarantee that models could be run in real‐time and interfaced to the real engine Electronic Control Unit (ECU). Being physically based models, they react to changes in the ECU calibration parameters. Once the models are validated, they are then integrated into a Sim-ulink¼ based architecture with all the Inputs/Outputs connections to the ECU. This Simulink¼ model is then deployed on a Hardware in the Loop (HiL) machine for ECU testing and calibration. The results for engine and EAS performance and emissions align with both steady‐state and transient measurements. Finally, two different applications of the HiL system are presented to explain the opportunities and advantages of this tool integrated within the standard engine development. Ex-amples cited refer to altitude calibration activities and soot loading investigation on vehicle duty cycles. The cases described in this work are part of the actual development of one of the latest engines developed by Kohler Engines: the KDI 1903 TCR Stage V. The application of this methodology reveals a great potential for engine development and may become an essential tool for calibration engineers

    Transfer of old ‘reactivated’ memory retrieval cues in rats

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    The present studies examined whether the retrieval of an old ‘reactivated’ memory could be brought under the control of new contextual cues. In Experiment 1 rats trained in one context were exposed to different contextual cues either immediately, 60 min, or 120 min after a cued reactivation of the training memory. When tested in the shifted context, subjects exposed shortly after reactivation treated the shifted context as the original context. This transfer diminished with longer post-reactivation delays. Experiment 2 replicated the basic finding and demonstrated that the transfer of the old retrieval cues was specific to the contextual cues present during exposure. These findings are consistent with previous research (i.e., Briggs, Fitz, & Riccio, in press) showing the transfer of retrieval cues for a new memory, and demonstrating a similarity (in this case) between newly acquired and old reactivated memories

    Transfer of extinction retrieval cues attenuates the renewal effect in rats

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    An experiment using rats investigated whether retrieval cues for an extinction memory could also be brought under the control of cues not physically present during extinction learning. Following the extinction of a fear motivated task in a context different from original learning, rats were exposed to the training context either immediately, 30 min, or 60 min after extinction. When tested back in the original context, rats that were exposed to the training context immediately following extinction treated the context as if it had received extinction in that setting, i.e., no renewal. This attenuation of renewal was reduced or eliminated with longer post-extinction delays, which suggests the importance of an active extinction memory during exposure. These findings are consistent with other research examining the transfer of retrieval cues using original memories and old reactivated memories, and in this case demonstrate a similarity between extinction learning with original acquisition

    Fate of the original retrieval cues following the transfer of memory in rats

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    Exposure to contextual cues immediately after conditioning enables the new stimuli to retrieve the target memory. But what is the fate of the original cues after this type of transfer of properties? Have they been supplanted by the new cues, or are both sets of stimuli now effective? To address this issue, an experiment was conducted investigating the effectiveness of the original training cues following the transfer of retrieval cues to a new context. Rats were exposed to contextual cues different from training immediately after learning a punishment task. Subjects tested in the new context treated the context as if it were the original, i.e., retrieval cues were transferred to the shifted context. In addition, this transfer had no effect on the original memory as rats that were tested in the original context behaved similarly to those tested in the shifted context. It appears that this transfer of retrieval cues is not a case of erase-and-update, but rather the cues remain for the original context and also become associated with the new context where exposure took place

    Damage evolution in fuselage stiffened composite panels under asymmetrical bending loading conditions

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    In this paper, the damage mechanisms of reinforced composite panels subjected to symmetrical and asymmetrical flexural loading conditions have been investigated. The composite components are representative of a regional aircraft fuselage. Three-point bending tests numerical simulations have been used to assess the influence of the different test parameters on the damage behavior of the investigated component. Then, the most representative configuration has been selected for the experimental bending test. the outputs from the numerical simulations, in terms of stiffness and damage onset and propagation, has been employed, in combination with the experimental data, to accurately describe the damage mechanisms associated to the asymmetric application of the load

    Kinematic Approach for a Global-Local Coupling: Compressive Behaviour of a Delaminated Panel:

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    A kinematic approach to global/local coupling has been applied to investigate the behaviour of a delaminated stiffened composite panel, by using an in-house finite element based procedure. The delamination growth phenomenon has been simulated by employing fracture elements implemented in the B2000++Âź code, which are based on the Modified Virtual Crack Closure Technique (MVCCT); this technique is able to compute the energy release rate on the delamination front for each fracture mode. A very fine three-dimensional mesh in the delaminated region has been considered in order to obtain a good prediction of the delamination growth. The rest of the structure has been modelled by means of shell elements. A global/local approach based on point-wise multipoint constraint has been implemented in the in-house-code and used to connect shell meshes to solid ones. A numerical application on a delaminated composite stiffened panel taken from literature has been introduced. Models characterized by different levels of complexity, i.e. without delamination, with delamination, with delamination growth have been considered and compared to understand the effectiveness of the introduced kinematic approach

    I-21 Current therapeutic guidelines in Duchenne Muscular Dystrophy to prolong life

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    Duchenne's myopathy is an X-linked disease with well defined evolutionary phases, characterized by degradation of the walking function, development of evolutive scoliosis and progressive decline of the respiratory function leading patients to premature death. In 1985 Y. Rideau in France carried out a new global therapeutic strategy for treatment of lower limb deformities, scoliosis deformity and progressive restrictive syndrome. The indication for surgery at the lower limbs is made very early, at the onset of the first signs of disease. The procedures are carried out at the same time and always bilaterally; they include: (i) hip section of superficial flexors; (ii) iliotibial band resection; (iii) subcutaneous tenotomy of semitendineous and gracilis; (iv) subcutaneous lengthening of Achilles tendons. In the post-operative period, the patient begins exercises of active and passive mobility in few days and after three weeks recovers his performances; ambulation will remain almost normal for several years. A comparison of two groups of patients, the first precociously operated on the lower limbs, the other one not operated, shows better performances in the operated group. The indications for surgical treatment of Duchenne scoliosis must be made after the loss of ambulation and not too late, to avoid the concurrent respiratory restrictive syndrome makes the patient inoperable. Over ten years ago, in Poitiers, a specific instrumentation for Duchenne scoliosis was created, providing for cylindrical rods fixed by peduncular screws at the sacro-lumbar level. On the dorso-lumbar level, the rod becomes flat to allow more flexibility of the trunk. The complications observed in a group of 55 patients operated for scoliosis, consisted in 2 cases of breaking of rods and 1 superficial infection. The surgery approach in DMD has the double aim to prolong the time of the autonomous ambulation and to avoid the evolution of scoliosis, limiting the harmful effects of the scoliosis on the respiratory function. However, the surgery alone is unable to prolong the life expectancy in these patients, without treating the restrictive respiratory syndrome, first by nasal ventilation and then by elective tracheotomy, essential for the survival of the patient
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