63 research outputs found
Toward Intelligent Biped-Humanoids Gaits Generation
In this chapter we will highlight our experimental studies on natural human
walking analysis and introduce a biologically inspired design for simple
bipedal locomotion system of humanoid robots. Inspiration comes directly from
human walking analysis and human muscles mechanism and control. A hybrid
algorithm for walking gaits generation is then proposed as an innovative
alternative to classically used kinematics and dynamic equations solving, the
gaits include knee, ankle and hip trajectories. The proposed algorithm is an
intelligent evolutionary based on particle swarm optimization paradigm. This
proposal can be used for small size humanoid robots, with a knee an ankle and a
hip and at least six Degrees of Freedom (DOF).Comment: 15 page
Composición y caracterización mediante GC-MS de aceite esencial extraído de Nicotiana glauca Graham
Fresh leaves of N. glauca were collected from the northern region of Tunisia. The leaves were submitted to water distillation for 4 h, using a Clevenger-type apparatus. The obtained essential oils were dried over anhydrous sodium sulphate and after filtration, stored at 4 °C until use. The chemical composition of the isolated essential oil was analyzed by gas chromatography–mass spectrometry (GC–MS). Eighteen compounds were identified: eugenol, the major compound in the essential oil, was present at a high level (58.49%), followed by nonadecane, eugenyl acetate and tridecane, 3-methyl at 6.38; 5.57 and 5.19%, respectively. The percentage of compounds dodecane, 2, 6, 11 trimethyl, tetradecane, docosane, tricosane and 1, 2-benzene dicarboxilic, dibutyl ester varied between 1 and 2%; whereas the other compounds (including limonene, and saturated hydrocarbons) remained at low percentages, not exceeding 1%. This study could be very useful for the characterization, pharmaceutical and therapeutic applications of the essential oil from N. glauca.Las hojas frescas de N. glauca se recolectaron en la región norte de Túnez. Las hojas se sometieron a destilación en agua durante 4 h, utilizando un aparato de destilación tipo Clevenger. Los aceites esenciales obtenidos se secaron y filtraron sobre sulfato de sodio anhidro y se almacenaron a 4 °C hasta su uso. La composición química del aceite esencial aislado se analizó mediante cromatografía de gases y espectrometría de masas (GC-MS). Se identificaron dieciocho compuestos: eugenol es el compuesto mayoritario (58,49%), seguido por nonadecano, acetato de eugenilo y tridecano, 3-metilo con 6,38%; 5,57% y 5,19% respectivamente. El porcentaje de los compuestos: dodecano, 2,6,11 trimetil, tetradecano, docosano, tricosano y 1,2-benceno dicarboxílico, dibutil éster varió entre 1 y 2%, mientras que el resto de compuestos (incluido el limoneno e hidrocarburos saturados) permanecieron en cantidades que no superan el 1%. Este estudio de caracterización podría ser de gran utilidad para aplicaciones farmacéuticas y terapéuticas del aceite esencial de N. glauca
Experimental Investigation on the Properties of a Recycled Aggregate Concrete Based on Waste of the Industrial Mineral Additions
This study investigates the possible effects of incorporating different industry wastes during manufacturing of concrete, with percentages ranging from 0% to 30%, and assesses the influence of these combinations (mineral additions and recycled aggregates) on the properties of a recycled concrete comprised of these two main constituents products. Recycled concrete samples with different combinations of mineral additions at various dosages were used to determine these properties in the fresh and hardened states. The ”Design-expert” methodology was used to analyse the results after 7, 14 and 28 days, identifying correlations and the effects of the different variables. The results obtained showed the advantageous effect of incorporating the pozzolana and slag into the concrete mixture at dosages of 15% and 30%, they also demonstrated the low optimal percentage of marble fillers of 5%. These findings suggest that replacing clinker with industrial waste could limit the dust and CO2 emissions into the atmosphere during concrete manufacture, offering environmental advantages as well as conserving the natural resources of aggregate recovery from C&D wastes.
Keywords: environmental concrete, mineral additions, recycled aggregate, design expert method
A Joint Linearization/Companding Approach for Improving a CO-OFDM Transmitter
International audience—The joint use of peak-to-average power ratio (PAPR) reduction and linearization via digital predistortion is investigated in this letter, with the view to improve the performances of coherent optical OFDM (CO-OFDM) systems employing a semiconductor optical amplifier (SOA). PAPR reduction is performed via Wang's nonlinear companding transform (WNCT), which has been recently pointed out as a pertinent choice for optical communications, and a Filter Lookup Table (FLUT) scheme is considered for linearizing the transmitter. Experimental results prove the effectiveness of the proposed scheme, as a lower EVM is achieved with respect to system implementations using only PAPR reduction or linearization
Chemical and Biological Properties of Sodium Alginates Isolated from Tow Brown Algae Dictyopteris Membranaceae and Padina Pavonica
Polysaccharides are known to have interesting biological activities. To date polysaccharides extracted from Tunisian seaweed have not been fully studied. In this paper we tried to isolate sodium alginate from two brown algae and evaluate their biological activities. Two brown seaweeds Dictyopteris membranaceae and Padina pavonica were treated with selective solvents to extract sodium alginate. Analyses were performed to determine their IR spectra, uronic acid’s content and biological properties (antioxidant and gastroprotective activities). Results showed that sodium alginate extracted from D. membranaceae contained 65% of uronic acid while this extracted from P. pavonica contained only 9% of uronic acid. These polysaccharides showed also variation in the structure and the activities. Sodium alginate extracted from D. membranaceae had the highest antioxidant activity with ED50 of 20µg/ml in the DPPH test. Additionally, this polysaccharide had the most important gastroprotective activity with a percent of 97% at dose 50mg/kg. Our finding suggested that sodium alginates extracted from D. membranaceae and P. pavonica could be used as a natural source of antioxidant and gastroprotective agents.
 
Clinical significance of T-bet, GATA-3, and Bcl-6 transcription factor expression in bladder carcinoma
International audienceBackground: The aim of this study was to investigate the clinical significance of three immune cell-related transcription factors, T-bet, GATA-3 and Bcl-6 in bladder cancer in Tunisian patients.Methods: Expression of T-bet, GATA-3 and Bcl-6 genes was assessed using RT-qPCR in 65 bladder cancers from patients: 32 being diagnosed as low-and medium-grade, 31 as high-grade, 25 as muscle invasive stage and 39 as non-muscle invasive stage. Gene expression was statistically correlated according to the grade, the stage, tobacco consumption, the BCG response and disease severity.Results: T-bet levels in patients with high-grade bladder cancer were significantly elevated compared to patients with low-or medium-grade bladder cancer (p = 0.005). In invasive carcinoma (T2-T4), the T-bet levels were significantly higher than in superficial non-invasive bladder tumors (Tis, Ta, and T1) (p = 0.02). However, T-bet is predictive of the response to BCG. Its expression is high in good responders to BCG (p = 0.02). In contrast, the expression of GATA-3 and Bcl-6 in non-invasive carcinoma (p = 0.008 and p = 0.0003) and in patients with low-and medium-grade cancers (p = 0.001 and p < 0.0001) is significantly higher than in invasive bladder tumors and in patients with high-grade bladder carcinoma, respectively. In addition, heavy smokers, whose tumors express low levels of GATA-3 and Bcl-6, are poor responders to BCG (p = 0.01 and p = 0.03). Finally, better patient survival correlated with GATA-3 (p = 0.04) and Bcl-6 (p = 0.04) but not T-bet expression.Conclusions: Our results suggest that T-bet expression in bladder tumors could be a positive prognostic indicator of BCG therapy, even if high levels are found in high-grade and stage of the disease. However, GATA-3 and Bcl-6 expression could be considered as predictive factors for good patient survival
Phytosterols, unsaturated fatty acid composition and accumulation in the almond kernel during harvesting period: Importance for development regulation
2-Phenylanilinium dihydrogen phosphate
In the crystal structure of the title compound, C12H12N+·H2PO4
−, the dihydrogen phosphate anions and the 2-phenylanilinium cations are associated via O—H⋯O and N—H⋯O hydrogen bonds so as to build inorganic layers around the x = 1/2 plane. The organic entities are anchored between these layers through C—H⋯O hydrogen bonds, forming a three-dimensional infinite network. The dihedral angle between the aromatic rings is 44.7 (4)°
Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients
Vehicle Routing Problem with Mixed Fleet of Conventional and Heterogenous Electric Vehicles and Time Dependent Charging Costs
International audienc
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