Nouvelles architectures de nano-systèmes polymères conducteurs à base de mélanges de nanocharges conductrices

Conductive polymer nanocomposites have been the object of intense researches and investigations recently. In fact, these materials have shown a great potential to be useful for many applications including different sectors. However, despite the promising results reported at the moment in this area, there is still a lack in the performance which can be improved by synchronization of their properties. In this PhD work, we present the preparation and full characterization of conductive polymer nanocomposites. Two kinds of conductive nanofillers (carbon nanotubes (MWCNTs) and silver nanoparticles (Ag-NPs)) have been dispersed either in a thermoplastic polymer (polyethylene PE), or in a thermoset matrix (epoxy amine). The conductive polymer nanocomposites obtained exhibit good electrical and/or thermal properties with conserving the mechanical properties ensured by low fillers fraction. The study was not only based on experimental characterizations but also on modulation to analyze the charge carrier transport at very low temperature in these systems to provide successful understanding to some basic properties which are still actually not fully investigated. Electrical properties are in good agreement with thermal properties. Electromagnetic shielding of our PE based nanocomposites have been studied by Nuclear Magnetic Resonance (NMR).Le domaine de nanocomposites polymères conducteurs a fait l’objet de nombreux travaux et recherches, vu que ces matériaux présentent un fort potentiel pour de nombreuses applications concernant différents secteurs. Toutefois, malgré les progrès et les résultats obtenus pour l’instant, les performances de ce type des matériaux restent insuffisantes pour certaines applications qui peuvent requérir l’association de diverses propriétés (électriques, thermiques, blindage électromagnétique…). Dans cette thèse, on détaille l’élaboration et la caractérisation de nanocomposites polymères conducteurs. Deux types de nanocharges conductrices (nanotubes de carbone (MWCNTs) et nanoparticules d’argent (Ag-NPs)) ont été dispersées soit dans un polymère thermoplastique (polyéthylène PE), soit dans une matrice thermodurcissable (résine époxy amine). Les nanocomposites polymères conducteurs obtenus ont présenté de bonnes propriétés électriques et thermiques ainsi qu’une bonne tenue mécanique favorisée par des taux de charges relativement faibles. La thèse a non seulement étudié des propriétés fondamentales d’un point de vue expérimental mais aussi plus théorique avec de la modélisation. Entre autres, on a pu analyser les mécanismes de conduction à très basses température dans ce type de composites. Les propriétés en termes de conductivité thermique se sont révélées cohérentes avec celles obtenues en conductivité électrique. Des propriétés de blindage électromagnétique de nos composites à base de PE ont été mis en évidence par résonance magnétique nucléaire (RMN)

Dystrophic Epidermolysis Bullosa: COL7A1 Mutation Landscape in a Multi-Ethnic Cohort of 152 Extended Families with High Degree of Customary Consanguineous Marriages

Dystrophic epidermolysis bullosa is a heritable skin disease manifesting with sub-lamina densa blistering, erosions, and chronic ulcers. COL7A1, encoding type VII collagen, has been identified as the candidate gene for dystrophic epidermolysis bullosa. In this study, we have identified COL7A1 mutations in a large multi-ethnic cohort of 152 extended Iranian families with high degree of consanguinity. The patients were diagnosed by clinical manifestations, histopathology, and immunoepitope mapping. Mutation detection consisted of a combination of single nucleotide polymorphism-based whole-genome homozygosity mapping, Sanger sequencing, and gene-targeted next-generation sequencing. A total of 104 distinct mutations in COL7A1 were identified in 149 of 152 families (98%), 56 (53%) of them being previously unreported. Ninety percent of these mutations were homozygous recessive, reflecting consanguinity in these families. Three recurrent mutations were identified in five or more families, and haplotype analysis suggested a founder effect in two of them. In conclusion, COL7A1 harbored mutations in the overwhelming majority of patients with dystrophic epi-dermolysis bullosa, and most of them in this Iranian cohort were consistent with autosomal recessive inheri-tance. The mutation profile attests to the impact of consanguinity in these families

Semi-Analytical Design of PDE Endpoint Controller for Flexible Manipulator With Non-Homogenous Boundary Conditions

This study proposes a new semi-analytical design and implementation method for nonlinear partial differential equation (PDE) control of a flexible manipulator. The proposed scheme considers the effects of the boundary input force and gravity on the payload, which results in non-homogenous boundary conditions. This objective is achieved based on a model transformation scheme for homogenizing boundary conditions, obtaining semi-analytical solutions for the corresponding PDE model. Model transformation is assigned as a hybrid exponential–polynomial function whose coefficients are conveniently calculable without the need for any additional boundary condition measurements. This eliminates the need to use intensive numerical solvers—for example, methods based on finite element analysis—and allows the implementation of sophisticated PDE control schemes considering fully nonlinear PDE models with high computation speed. The presented controller is robust to parametric model uncertainty due to its adaptive design. The precision and efficiency of calculating distributed states using the proposed model transformation are demonstrated based on experimental data for the flexible manipulator with respect to the ground truth camera-based motion capture system. Model transformation is also numerically implemented for the proposed nonlinear endpoint control method based on the original PDE model. Note to Practitioners—This paper investigates the difficulty of obtaining data describing the flexible manipulator pose required for precise control and analysis and proposes a computationally efficient method to overcome this issue.Peer reviewe

Amine-modified hyaluronic acid-functionalized porous silicon nanoparticles for targeting breast cancer tumors

Peer reviewe

Multigene Next-Generation Sequencing Panel Identifies Pathogenic Variants in Patients with Unknown Subtype of Epidermolysis Bullosa: Subclassification with Prognostic Implications

Purpose: Epidermolysis bullosa (EB), the prototype of heritable blistering diseases, is caused by mutations in as many as 19 distinct genes. In this study, we evaluated the molecular basis of EB in 93 families, many of them of unknown subtype. Methods: A next generation sequencing panel covering 21 EB-related genes was developed, and mutation profiles, together with clinical features, were used to classify the patients into distinct clinical categories. Results: A total of 72 pathogenic or likely pathogenic variants in 68 families were identified in 11 of the EB-associated candidate genes, most of them (75%) being homozygous consistent with considerable consanguinity in the cohort. Approximately half of the mutations (48.6%) were previously unreported. Refined analysis of the types of mutations with addition of variants of unknown significance suspected of causing clinically consistent disease in several patients allowed subclassification of patients into different subcategories of EB in 76 of 91 families, with prognostic implications. A genetically challenging case with homozygous loss-of-function pathogenic mutations in two different EB-associated genes resulting in different subtypes was identified. In addition, secondary findings included identification of known pathogenic variants in DSP associated with arrhythmogenic right ventricular cardiomyopathy. Conclusion: Utilization of next generation sequencing panel of EB-associated genes allowed diagnostic subclassification in the neonates particularly in families of unknown subtype, with prognostication of the overall long-term outcome of the disease

Robust Model Predictive Control for Robot Manipulators

Inherent nonlinearities, external disturbances and model uncertainties hinder the performance of controlling real-world systems. In the present study, we proposed a robust model prediction-based virtual decomposition control method (RMP-VDC) as a modification of the VDC using the model predictive control (MPC) to offer a practical solution for the real system control problem. The proposed method deals with uncertainties and external forces, as well as constraint matters, for complex nonlinear robot manipulators. By modifying the ideas from the VDC with MPC techniques, the time-varying state feedback control law for the ancillary controller is provided. The proposed method benefits from the introduction of a prediction horizon, which induces robustness and increases accuracy. The constrained optimization problem is analytically solved online by the continuous linearization of the nonlinear model and by employing the active set method. To validate the proposed controller, we performed the implementation on a real 7-degrees-of-freedom upper body exoskeleton robot, and the results were compared with those obtained using the adaptive VDC. The experimental results revealed increased accuracy for the proposed RMP-VDC in dealing with model uncertainties and interaction forces between humans and exoskeleton robots.acceptedVersionPeer reviewe

Recessive mutation in tetraspanin CD151 causes Kindler syndrome-like epidermolysis bullosa with multi-systemic manifestations including nephropathy

Epidermolysis bullosa (EB) is caused by mutations in as many as 19 distinct genes. We have developed a next-generation sequencing (NGS) panel targeting genes known to be mutated in skin fragility disorders, including tetraspanin CD151 expressed in keratinocytes at the dermal-epidermal junction. The NGS panel was applied to a cohort of 92 consanguineous families of unknown subtype of EB. In one family, a homozygous donor splice site mutation in CD151 (NM_139029; c.351 + 2T > C) at the exon 5/intron 5 border was identified, and RT-PCR and whole transcriptome analysis by RNA-seq confirmed deletion of the entire exon 5 encoding 25 amino acids. Immunofluorescence of proband's skin and Western blot of skin proteins with a monoclonal antibody revealed complete absence of CD151. Transmission electron microscopy showed intracellular disruption and cell-cell dysadhesion of keratinocytes in the lower epidermis. Clinical examination of the 33-year old proband, initially diagnosed as Kindler syndrome, revealed widespread blistering, particularly on pretibial areas, poikiloderma, nail dystrophy, loss of teeth, early onset alopecia, and esophageal webbing and strictures. The patient also had history of nephropathy with proteinuria. Collectively, the results suggest that biallelic loss-of-function mutations in CD151 underlie an autosomal recessive mechano-bullous disease with systemic features. Thus, CD151 should be considered as the 20th causative, EB-associated gene

Towards autonomic Internet of Things: recent advances, evaluation criteria, and future research directions

With the rise of the Internet of Things (IoT), tiny devices capable of computation and data transmission are being deployed across various technological domains. Due to the wide deployment of these devices, manual setup and management are infeasible and inefficient. To address this inefficiency, intelligent procedures must be established to enable autonomy that allows devices and networks to operate efficiently with minimal human intervention. In the traditional client-server paradigm, autonomic computing has been proven effective in minimising user intervention in computer systems management and will benefit IoT networks. However, IoT networks tend to be heterogeneous, distributed and resource-constrained, mandating the need for new approaches to implement autonomic principles compared to traditional approaches. We begin by introducing the basic principles of autonomic computing and its significance in IoT. We then discuss the self-* paradigm and MAPE loop from an IoT perspective, followed by recent works in IoT and key enabling technologies for enabling autonomic properties in IoT. Based on the self-* paradigm and MAPE loop analysis from the existing literature, we propose a set of qualitative characteristics for evaluating the autonomy of the IoT network. Lastly, we provide a comprehensive list of challenges associated with achieving autonomic IoT and directions for future research