120 research outputs found
Fistule carotido-caverneuse post-traumatique
Introduction : La fistule carotido-caverneuse (FCC) est une complication rare, mais grave des traumatismes craniofaciaux pouvant engager le pronostic fonctionnel oculaire et le pronostic vital. elle rĂ©alise une communication anormale entre le systĂšme artĂ©riel carotidien et le sinus caverneux.Buts : Rapporter un cas de FCC directe post-traumatique et Ă©tudier les aspects cliniques, diagnostiques et thĂ©rapeutiques de cette pathologie.Observation : Nous rapportons un cas de FCC apparue dans les suites dâun traumatisme craniofacial et survenue chez un homme de 25 ans ayant Ă©tĂ© victime dâun accident de la voie publique. Le diagnostic a Ă©tĂ© suspectĂ© devant lâapparition, au 19Ăšme jour dâhospitalisation, dâune exophtalmie unilatĂ©rale gauche pulsatile associĂ©e Ă un important chĂ©mosis et Ă une pupille arĂ©flectique. Une artĂ©riographie cĂ©rĂ©brale pratiquĂ©e 9 jours aprĂšs la constatation de lâexophtalmie a objectivĂ© une large FCC gauche. Une embolisation au moyen de deux ballonnets intravasculaires largables et de lâinjection de colle biologique a Ă©tĂ© rĂ©alisĂ©e au mĂȘme temps sans incidents permettant dâobtenir lâocclusion complĂšte de la fistule. LâĂ©volution a Ă©tĂ© marquĂ©e par la rĂ©gression de lâexophtalmie et du chĂ©mosis et par lâamĂ©lioration partielle de lâacuitĂ© visuelle.Conclusion : Le traitement des FCC est urgent et est principalement basĂ© sur la neuroradiologie interventionnelle. en effet, lâangiographie cĂ©rĂ©brale constitue lâexamen clĂ© et possĂšde un double intĂ©rĂȘt diagnostique et thĂ©rapeutique.Mots clĂ©s : fistule carotido-caverneuse, traumatisme craniofacial, artĂ©riographie cĂ©rĂ©brale, embolisation
Characterisation of bioenergetic pathways and related regulators by multiple assays in human tumour cells
Background: Alterations in cellular metabolism are considered as hallmarks of cancers, however, to recognize these alterations and understand their mechanisms appropriate techniques are required. Our hypothesis was to determine whether dominant bioenergetic mechanism may be estimated by comparing the substrate utilisation with different methods to detect the labelled carbon incorporation and their application in tumour cells. Methods: To define the bioenergetic pathways different metabolic tests were applied: (a) measuring CO2 production from [1-14C]-glucose and [1-14C]-acetate; (b) studying the effect of glucose and acetate on adenylate energy charge; (c) analysing glycolytic and TCA cycle metabolites and the number of incorporated 13C atoms after [U-13C]-glucose/[2-13C]-acetate labelling. Based on [1-14C]-substrate oxidation two selected cell lines out of seven were analysed in details, in which the highest difference was detected at their substrate utilization. To elucidate the relevance of metabolic characterisation the expression of certain regulatory factors, bioenergetic enzymes, mammalian target of rapamycin (mTOR) complexes (C1/C2) and related targets as important elements at the crossroad of cellular signalling network were also investigated. Results: Both [U-13C]-glucose and [1-14C]-substrate labelling indicated high glycolytic capacity of tumour cells. However, the ratio of certain 13C-labelled metabolites showed detailed metabolic differences in the two selected cell lines in further characterisation. The detected differences of GAPDH, ÎČ-F1-ATP-ase expression and adenylate energy charge in HT-1080 and ZR-75.1 tumour cells also confirmed the altered metabolism. Moreover, the highly limited labelling of citrate by [2-13C]-acetate-representing a novel functional test in malignant cells-confirmed the defect of TCA cycle of HT-1080 in contrast to ZR-75.1 cells. Noteworthy, the impaired TCA cycle in HT-1080 cells were associated with high mTORC1 activity, negligible protein level and activity of mTORC2, high expression of interleukin-1ÎČ, interleukin-6 and heme oxygenase-1 which may contribute to the compensatory mechanism of TCA deficiency. Conclusions: The applied methods of energy substrate utilisation and other measurements represent simple assay system using 13C-acetate and glucose to recognize dominant bioenergetic pathways in tumour cells. These may offer a possibility to characterise metabolic subtypes of human tumours and provide guidelines to find biomarkers for prediction and development of new metabolism related targets in personalized therapy. © 2016 Jeney et al
Role and task allocation framework for Multi-Robot Collaboration with latent knowledge estimation
In this work a novel framework for modeling role and task allocation in Cooperative Heterogeneous Multi-Robot Systems (CHMRSs) is presented. This framework encodes a CHMRS as a set of multidimensional relational structures (MDRSs). This set of structure defines collaborative tasks through both temporal and spatial relations between processes of heterogeneous robots. These relations are enriched with tensors which allow for geometrical reasoning about collaborative tasks. A learning schema is also proposed in order to derive the components of each MDRS. According to this schema, the components are learnt from data reporting the situated history of the processes executed by the team of robots. Data are organized as a multirobot collaboration treebank (MRCT) in order to support learning. Moreover, a generative approach, based on a probabilistic model, is combined together with nonnegative tensor decomposition (NTD) for both building the tensors and estimating latent knowledge. Preliminary evaluation of the performance of this framework is performed in simulation with three heterogeneous robots, namely, two Unmanned Ground Vehicles (UGVs) and one Unmanned Aerial Vehicle (UAV)
Approaches in biotechnological applications of natural polymers
Natural polymers, such as gums and mucilage, are biocompatible, cheap, easily available and non-toxic materials of native origin. These polymers are increasingly preferred over synthetic materials for industrial applications due to their intrinsic properties, as well as they are considered alternative sources of raw materials since they present characteristics of sustainability, biodegradability and biosafety. As definition, gums and mucilages are polysaccharides or complex carbohydrates consisting of one or more monosaccharides or their derivatives linked in bewildering variety of linkages and structures. Natural gums are considered polysaccharides naturally occurring in varieties of plant seeds and exudates, tree or shrub exudates, seaweed extracts, fungi, bacteria, and animal sources. Water-soluble gums, also known as hydrocolloids, are considered exudates and are pathological products; therefore, they do not form a part of cell wall. On the other hand, mucilages are part of cell and physiological products. It is important to highlight that gums represent the largest amounts of polymer materials derived from plants. Gums have enormously large and broad applications in both food and non-food industries, being commonly used as thickening, binding, emulsifying, suspending, stabilizing agents and matrices for drug release in pharmaceutical and cosmetic industries. In the food industry, their gelling properties and the ability to mold edible films and coatings are extensively studied. The use of gums depends on the intrinsic properties that they provide, often at costs below those of synthetic polymers. For upgrading the value of gums, they are being processed into various forms, including the most recent nanomaterials, for various biotechnological applications. Thus, the main natural polymers including galactomannans, cellulose, chitin, agar, carrageenan, alginate, cashew gum, pectin and starch, in addition to the current researches about them are reviewed in this article.. }To the Conselho Nacional de Desenvolvimento CientfĂico e TecnolĂłgico (CNPq) for fellowships (LCBBC and MGCC) and the Coordenação de Aperfeiçoamento de Pessoal de NvĂel Superior (CAPES) (PBSA). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and COMPETE 2020 (POCI-01-0145-FEDER-006684) (JAT)
Application of Feedforward Neural Network for Induction Machine Rotor Faults Diagnostics using Stator Current
Faults and failures of induction machines can lead to excessive downtimes and generate large losses in terms of maintenance and lost revenues. This motivates motor monitoring, incipient fault detection and diagnosis. Non-invasive, inexpensive, and reliable fault detection techniques are often preferred by many engineers. In this paper, a feedforward neural network based fault detection system is developed for performing induction motors rotor faults detection and severity evaluation using stator current. From the motor current spectrum analysis and the broken rotor bar specific frequency components knowledge, the rotor fault signature is extracted and monitored by neural network for fault detection and classification. The proposed methodology has been experimentally tested on a 5.5Kw/3000rpm induction motor. The obtained results provide a satisfactory level of accuracy
Synthesis, characterization and optical spectroscopy of GdPO4:Er3+
A series of Er3+-doped GdPO4 phosphors was synthesized using a conventional solid-state reaction. The monazite structure (space group P121/n1) of the obtained materials was confirmed using X-ray diffraction and Fourier transform infrared spectroscopy. Their optical spectra (excitation, emission, absorption, decay curves) were measured at room temperature in the visible and near-infrared (NIR) regions. The UVâvisibleâNIR optical absorption spectrum of GdPO4:7% Er3+ was analyzed based on JuddâOfelt (JâO) theory and the JâO intensity parameter (Ω2, Ω4, Ω6) was calculated. JâO intensity parameters were used to evaluate spontaneous emission properties such as branching ratios, transition probabilities, and radiative lifetime. The calculated quantum efficiency of the 1.5 ÎŒm emission (4I13/2â4I15/2) was calculated to be 89%. This result proved that GdPO4:Er3+ is suitable for use in optical amplifiers and is a potential host for laser applications. The most interesting transitions, located at about 540 nm, and 1.0 and 1.5 ÎŒm were investigated as a function of doping level and of temperature, to assess the conditions needed for the highest emission performance and to explore the range of application, in particular in the fields of lighting, thermal sensing, and of phosphors for bio-imaging
Structural and magnetic properties of mixed Co-Ln (Ln = Nd, Sm, Eu, Gd and Ho) diethyleneglycolate complexes
Ăquipe 103 : ComposĂ©s intermĂ©talliques et matĂ©riaux hybridesInternational audienceNew hybrid compounds LnCoCl(deg)(2) (deg = diethyleneglycolate; Ln = Nd, Sm, Eu, Gd and Ho) have been synthesized by mixing cobalt and rare earth cations in a boiling diethyleneglycol (degH(2)) medium. Their crystallographic structures have been ab initio solved from synchrotron powder diffraction data. They consist of edge sharing tetrameric sub-units [(Ln(2)CO(2))(deg)(4)(Cl)(2)] forming 1D infinite chains along the c parameter of a monoclinic unit cell (SG = C2/c). The five-and seven-coordination of Co2+ and Ln(3+) cations inferred from the crystallographic results is confirmed by UV-visible absorption and Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy. In the LnCoCl(deg)(2) (Ln = Nd, Sm, Eu, Gd, Ho) series, weak antiferromagnetic superexchange interactions have been evidenced, between high spin Co2+ and Ln(3+) orbitally degenerate cations. These materials are considered as potential precursors for the simultaneous reduction of Co-Ln-glycolate species into bimetallic nanoparticles by the polyol process
Investigation of capillary impregnation for permeability prediction of fibrous reinforcements
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