Dialog Planning and Domain Knowledge Modeled in terms of Tasks and Methods - A Flexible Framework for Dialog Managing

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Synthesis of ZnO Microwires and Tetrapods by Optical Furnace

International audienceIn this study, a new route is described in order to obtain wires which can reach a few hundreds of micrometers long. ZnO rod is sintered at 900 1C for 10 h in air. Then the centimetric rod is placed in an optical furnace. The optical furnace allows to reach a thermal gradient of about 350 1C/cm. In a first step, the vaporization of ZnO occurs, and in a second step the condensation of ZnO on the rod appears and leads to the growth of ZnO microwires (MWs). In few minutes, the MWs can reach in the c-direction a dimension higher than 100 μm with a diameter close to ten microns. The shape of the MWs is hexagonal which is consistent with the crystal structure of ZnO (P63mc group). The MWs exhibit a high crystalinity. & 2013 Elsevier B.V. All rights reserved

A FPGA partial reconfiguration design approach for cognitive radio based on NoC architecture

International audienceA Cognitive Radio is the final point of software-defined radio platform evolution: a fully reconfigurable radio that changes its communication modules depending on network and/or user demands. His definition on reconfigurability is very broad and we only focus on the heterogeneous reconfigurable hardware platform for Cognitive Radio. Software Defined Radio (SDR) basically refers to a set of techniques that permit the reconfiguration of a communication system without the need to change any hardware system element. The goal of Software Defined Radio is to produce communication devices which can support several different services. These terminals must adapt their hardware structure in function of the wireless networks such as GSM, UMTS, wireless LAN standards like IEEE 802.11a/b/g... As a consequence, NoC offer good perspectives to future SoC in the way to satisfy SDR concept. Conception, validation and evaluation of solutions for NoC design (mapping of cores, topology, FIFO and link sizes) is conducted through simulations. We are proposing to extend the NoC structure to a FPGA where PR (Partial Reconfiguration) is used to dynamically reconfigure the requested IP block of the telecommunication chain. This work is part of our contribution for E2RII project and IDROMEL project

Cortical activation of unilateral upper limb tasks: Perspectives for stroke rehabilitation

International audienceBackground and Aim: Post-stroke brain activations and their evolution through rehabilitation is a subject of major interest. Two non-invasive neuroimaging methods allow for recording the task-related brain activation for bedside use or in field monitoring: functional near-infrared spectroscopy (fNIRS) and electroencephalography (fEEG) respectively based on haemodynamic response and electrical activity of brain regions. Coupling both methods could lead to a better spatiotemporal mapping of the movement-related cortical activity to unveil underlying mechanisms of upper limb (UL) recovery. This fNIRS-fEEG study aims to depict reference activation patterns of motor cortex related to motor performance during UL functional tasks. Methods: Young healthy participants realized two unilateral UL tasks: i) a reaching target task and ii) a circular tracing task with speed and accuracy. A combined fNIRS-fEEG system was used to record motor cortex activations during each task. Results: With 20 healthy young subjects we replicated the classical kinematics results of the healthy UL movement. Neuro-imagery results provided by the fNIRS showed a co-activation of both motor cortex with a greater contralateral activity. With the EEG we highlighted power modification in the alpha-beta rhythm with a desynchronization occurring at movement. Conclusion: In parallel to the description of the reference brain pattern of UL movement, we showed that combined fNIRS-fEEG can be used in a rehabilitation unit to provide a “Holter of the brain plasticity” during functional movement. Further analysis with the older healthy subjects will give us information about ageing effects. Perspectives of this project will be the exploration of these brain-movement patterns in post-stroke patients in rehabilitation

Attentional Lapses in Attention-Deficit/Hyperactivity Disorder: Blank Rather Than Wandering Thoughts

International audiencePeople with attention-deficit/hyperactivity disorder (ADHD) have difficulties sustaining their attention on external tasks. Such attentional lapses have often been characterized as the simple opposite of external sustained attention, but the different types of attentional lapses, and the subjective experiences to which they correspond, remain unspecified. In this study, we showed that unmedicated children (ages 6–12) with ADHD, when probed during a standard go/no-go task, reported more mind blanking (a mental state characterized by the absence of reportable content) than did control participants. This increase in mind blanking happened at the expense of both focused and wandering thoughts. We also found that methylphenidate reverted the level of mind blanking to baseline (i.e., the level of mind blanking reported by control children without ADHD). However, this restoration led to mind wandering more than to focused attention. In a second experiment, we extended these findings to adults who had subclinical ADHD. These results suggest that executive functions impaired in ADHD are required not only to sustain external attention but also to maintain an internal train of thought

Kinetic analysis of the interaction of Mos1 transposase with its inverted terminal repeats reveals new insight into the protein-DNA complex assembly.

International audienceTransposases are specific DNA-binding proteins that promote the mobility of discrete DNA segments. We used a combination of physicochemical approaches to describe the association of MOS1 (an eukaryotic transposase) with its specific target DNA, an event corresponding to the first steps of the transposition cycle. Because the kinetic constants of the reaction are still unknown, we aimed to determine them by using quartz crystal microbalance on two sources of recombinant MOS1: one produced in insect cells and the other produced in bacteria. The prokaryotic-expressed MOS1 showed no cooperativity and displayed a Kd of about 300 nM. In contrast, the eukaryotic-expressed MOS1 generated a cooperative system, with a lower Kd (∼ 2 nm). The origins of these differences were investigated by IR spectroscopy and AFM imaging. Both support the conclusion that prokaryotic- and eukaryotic-expressed MOS1 are not similarly folded, thereby resulting in differences in the early steps of transposition

Brain-movement relationship during upper-limb functional movements in chronic post-stroke patients

Background Following a stroke, brain activation reorganisation, movement compensatory strategies, motor performance and their evolution through rehabilitation are matters of importance for clinicians. Two non-invasive neuroimaging methods allow for recording task-related brain activation: functional near-infrared spectroscopy (fNIRS) and electroencephalography (fEEG), respectively based on haemodynamic response and neuronal electrical activity. Their simultaneous measurement during movements could allow a better spatiotemporal mapping of brain activation, and when associated to kinematic parameters could unveil underlying mechanisms of functional upper limb (UL) recovery. This study aims to depict the motor cortical activity patterns using combined fNIRS-fEEG and their relationship to motor performance and strategies during UL functional tasks in chronic post-stroke patients. Methods Twenty-one healthy old adults and 21 post-stroke patients were recruited and realized two standardised functional tasks of the UL: a paced-reaching task where they had to reach a target in front of them and a circular steering task where they had to displace a target using a hand-held stylus, as fast as possible inside a circular track projected on a computer screen. The activity of the bilateral motor cortices and motor performance were recorded simultaneously utilizing a fNIRS-fEEG and kinematics platform. Results and conclusions Kinematic analysis revealed that post-stroke patients performed worse in the circular steering task and used more trunk compensation in both tasks. Brain analysis bilateral motor cortices revealed that stroke individuals over-activated during the paretic UL reaching task, which was associated with more trunk usage and a higher level of impairment (clinical scores). This work opens up avenues for using such combined methods to better track and understand brain-movement evolution through stroke rehabilitation

Dosimetric characterisation and application to radiation biology of a kHz laser-driven electron beam

Laser-plasma accelerators can produce ultra-short electron bunches in the femtosecond to picosecond duration range, resulting in very high peak dose rates in comparison with clinical accelerators. This unique characteristic motivates their possible application to radiation biology studies to elucidate the effect of high peak dose rates and peculiar temporal structures on the biological response of living cells, which might improve the differential response between tumour and healthy tissues. Electron beams driven by kHz laser systems are an attractive option among laser-plasma accelerators since the high repetition rate can boost the mean dose rate and improve the stability of the delivered dose in comparison with J-class laser accelerators running at few Hz. In this work, we present the dosimetric characterisation of a kHz, low energy laser-driven electron source and preliminary results on in-vitro irradiation of cancer cells. A shot-to-shot dosimetry protocol enabled monitoring of the beam stability and the irradiation conditions for each cell sample. Results of survival assays on HCT116 colorectal cancer cells are in good agreement with previous findings reported in the literature and validate the robustness of the dosimetry and irradiation protocol

Recovering arm function in chronic stroke patients using combined anodal HD-tDCS and virtual reality therapy (ReArm): a study protocol for a randomized controlled trial

International audienceAbstract Background After a stroke, 80% of the chronic patients have difficulties to use their paretic upper limb (UL) in activities of daily life (ADL) even after rehabilitation. Virtual reality therapy (VRT) and anodal transcranial direct current stimulation (tDCS) are two innovative methods that have shown independently to positively impact functional recovery of the paretic UL when combined with conventional therapy. The objective of the project will be to evaluate the impact of adding anodal high-definition (HD)-tDCS during an intensive 3-week UL VRT and conventional therapy program on paretic UL function in chronic stroke. Methods The ReArm project is a quadruple-blinded, randomized, sham-controlled, bi-centre, two-arm parallel, and interventional study design. Fifty-eight chronic (> 3 months) stroke patients will be recruited from the Montpellier and Nimes University Hospitals. Patients will follow a standard 3-week in-patient rehabilitation program, which includes 13 days of VRT (Armeo Spring, 1 × 30 min session/day) and conventional therapy (3 × 30 min sessions/day). Twenty-nine patients will receive real stimulation (4x1 anodal HD-tDCS montage, 2 mA, 20 min) to the ipsilesional primary motor cortex during the VRT session and the other 29 patients will receive active sham stimulation (2 mA, 30 s). All outcome measures will be assessed at baseline, at the end of rehabilitation and again 3 months later. The primary outcome measure will be the wolf motor function test. Secondary outcomes will include measures of UL function (Box and Block Test), impairment (Fugl Meyer Upper Extremity), compensation (Proximal Arm Non-Use), ADL (Actimetry, Barthel Index). Other/exploratory outcomes will include pain, fatigue, effort and performance, kinematics, and motor cortical region activation during functional motor tasks. Discussion This will be the first trial to determine the impact of adding HD-tDCS during UL VRT and conventional therapy in chronic stroke patients. We hypothesize that improvements in UL function will be greater and longer-lasting with real stimulation than in those receiving sham. Trial registration The ReArm project was approved by The French Research Ethics Committee, (Comité de Protection des Personnes-CPP SUD-EST II, N°ID-RCB: 2019-A00506-51, http://www.cppsudest2.fr/ ). The ReArm project was registered on ClinicalTrials.gov ( NCT04291573 , 2 nd March 2020