246 research outputs found
Soutenance de thèse : S. Snoussi, "Gouverner avec art. Le problème de l'exercice du pouvoir dans les premiers miroirs des princes arabo-musulmans", Créteil, 14 nov. 2015
No full textNous avons le plaisir de vous annoncer la prochaine soutenance de thèse de : Syrine SNOUSSI "Gouverner avec art. Le problème de l'exercice du pouvoir dans les premiers miroirs des princes arabo-musulmans" le 14 novembre 2015, à 9h30 en Salle des Thèses , UPEC - Campus Centre 61, avenue du Général de Gaulle 94 000 Créteil. Directeur de thèse : Ali BENMAKHLOUF (UPEC) Composition du jury : Jean-Baptiste BRENET (Université Paris 1 Panthéon Sorbonne) Makram ABBES (ENS Lyon) Guillaume LE BLANC (U..
Assuring company’s performance and financial equilibrium in the crisis context
No full textThis paper aims at highlighting the important role of the equity capital, on the one hand in achieving enough financial results, both for the compensation of the owners as expected and for the solid development of the company and, on the other hand, in ensuring a high protection against risks, especially against the risk of bankruptcy and also against the financial risk. The study which has been conducted highlights the fact that companies that have a high equity capital fulfill more successfully the two objectives of the company’s financial management compared to those that excessively resort to loanscompany’s financial management, equity capital, profitability, financial risk, bankruptcy risk
In-vitro anti-Vibrio spp. activity and chemical composition of some Tunisian aromatic plants
No full textThe Impact of Greenhouse and Field Growth Conditions on Chenopodium quinoa Willd Accessions’ Response to Salt Stress: A Comparative Approach
No full textQuinoa’s exceptional capacity to tolerate high salt levels presents a promising solution to the agricultural challenges posed by salt stress. This study aimed to explore salt stress effects on three quinoa accessions (18 GR, R-132, and DE-1) and to compare the influence of greenhouse and field growing conditions on their salinity tolerance. The plants were irrigated by 50, 100, 150, and 200 mM NaCl concentrations. The results showed that quinoa plants’ response to morphological, physiological, biochemical, and enzymatic parameters was influenced by NaCl concentration, accession, growing conditions, and their interactions. As salinity irrigation increased, aerial part length and leaf area decreased significantly (p −2·s−1 for greenhouse and open field conditions, respectively. NaCl stimulated MDA and H2O2 in both conditions for all accessions, and the DE-1 accession displayed the lowest levels. Proteins, sugars, proline, peroxidase, ascorbate peroxidase, and catalase were stimulated by salt stress, except in the R-132 accession. Field cultivation resulted in a more severe salinity response. Greenhouse conditions may enhance quinoa’s salt tolerance due to the less demanding growth conditions. DE-1 exhibited the highest salt tolerance, while R-132 showed the lowest. This study sets the stage for further research into the genetic basis of salt tolerance in various quinoa accessions, optimizing growth in salty regions through farming practices, and confirming the obtained results in real-world conditions for sustainable agriculture
Phytochemistry, bioactivities, pharmacokinetics and toxicity prediction of selaginella repanda with its anticancer potential against human lung, breast and colorectal carcinoma cell lines
No full textIn this study, we investigated the bioactive potential (antibacterial and antioxidant), an-ticancer activity and detailed phytochemical analysis of Selaginella repanda (S. repanda) ethanolic crude extract for the very first time using different in vitro approaches. Furthermore, computer-aided prediction of pharmacokinetic properties and safety profile of the identified phytoconstituents were also employed in order to provide some useful insights for drug discovery. S. repanda, which is a rich source of potent natural bioactive compounds, showed promising antibacterial activity against the tested pathogenic bacteria (S. aureus, P. aeruginosa, E. coli and S. flexneri). The crude extract displayed favorable antioxidant activity against both 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50 = 231.6 μg/mL) and H2 O2 (IC50 = 288.3 μg/mL) molecules. S. repanda also showed favorable and effective anticancer activity against all three malignant cancer cells in a dose/time dependent manner. Higher activity was found against lung (A549) (IC50 = 341.1 μg/mL), followed by colon (HCT-116) (IC50 = 378.8 μg/mL) and breast (MCF-7) (IC50 = 428.3 μg/mL) cancer cells. High resolution-liquid chromatography–mass spectrometry (HR-LC–MS) data of S. repanda crude extract revealed the presence of diverse bioactive/chemical components, including fatty acids, alcohol, sugar, flavonoids, alkaloids, terpenoids, coumarins and phenolics, which can be the basis and major cause for its bioactive potential. Therefore, achieved results from this study confirmed the efficacy of S. repanda and a prospective source of naturally active biomolecules with antibacterial, antioxidant and anticancer potential. These phytocompounds alone with their favorable pharmacokinetics profile suggests good lead and efficiency of S. repanda with no toxicity risks. Finally, further in vivo experimental investigations can be promoted as probable candidates for various therapeutic functions, drug discovery and development
Adesive properties of environmental Vibrio alginolyticus strains to biotic and abiotic surfaces
No full textDistribution of some virulence related-properties of Vibrio alginolyticus strains isolated from Mediterranean seawater (Bay of Khenis, Tunisia): investigation of eight Vibrio cholerae virulence genes
No full textIsolation and identification of an antibacterial compound from Diplotaxis harra (Forssk.) Boiss
No full textThe emergence of the antibiotic resistance is an ongoing problem in public health, and therefore the search for new natural molecules represents an alternative to synthetic drugs. The aim of this study was to test the antibacterial activity of ten Mediterranean plants (Diplotaxis harra, Ecballium elaterium, Pergularia tomentosa, Myrtus communis, Solanum villosum, Solanum sodomaeum, Peganum harmala, Lepidium sativum, Pistacia lentiscus, and Calendula arvensis) against seven pathogenic bacteria (Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Klebsiella sp., Salmonella enteritidis, and Bacillus cereus) using the disk diffusion method, in order to isolate and identify the active compound(s). Dichloromethane extract of D. harra flower showed the best activity against S. aureus and L. monocytogenes (MIQ = 30 μg/disk and 15 μg/disk, respectively). This extract was submitted to a bio-guided purification using Thin Layer Chromatography (TLC)-bioautography, and an antibacterial fraction (MIQ = 2 μg/disk) was isolated. The active fraction was characterized by RP-HPLC-DAD-ESI-MSn and GC–MS. Sulforaphane, an isothiocyanate known for its anti-cancer, antioxidant, and anti-inflammatory properties, was identified as antibacterial agent in D. harra for the first time. Due to its high antibacterial activity, sulforaphane could be considered a good candidate for the selection of new natural antibacterial molecules
Generic sections of essentially isolated determinantal singularities
No full textInternational audienceWe study the essentially isolated determinantal singularities (EIDS), defined by Ebeling and Gusein-Zade [S. M. Gusein-Zade and W. Ebeling, On the indices of 1-forms on determinantal singularities, Tr. Mat. Inst. Steklova 267 (2009) 119-131], as a generalization of isolated singularity. We prove in dimension 3, a minimality theorem for the Milnor number of a generic hyperplane section of an EIDS, generalizing the previous results by Snoussi in dimension 2. We define strongly generic hyperplane sections of an EIDS and show that they are still EIDS. Using strongly general hyperplanes, we extend a result of Le concerning the constancy of the Milnor number
Bioactivities and in silico study of Pergularia tomentosa L. phytochemicals as potent antimicrobial agents targeting type IIA topoisomerase, TyrRS, and Sap1 virulence proteins
No full textPergularia tomentosa L. (P. tomentosa) has been largely used in Tunisian folk medicine as remedies against skin diseases, asthma, and bronchitis. The main objectives of this study were to identify phytochemical compounds that have antioxidant and antimicrobial properties from the stem, leaves, and fruit crude methanolic extracts of P. tomentosa, and to search for tyrosyl-tRNA synthetase (TyrRS), topoisomerase type IIA, and Candidapepsin-1 (SAP1) enzyme inhibitors through molecular docking study. Phytochemical quantification revealed that fruit and leaves extracts displayed the highest total flavonoids (582 mg QE/g Ex; 219 mg QE/g Ex) and tannins content (375 mg TAE/g Ex; 216mg TAE/g Ex), also exhibiting significant scavenging activity to decrease free radicals for ABTS, DPPH, β-carotene, and FRAP assay with I.C50 values (> 1 mg/mL). Additionally, promising antimicrobial activities towards different organs have been observed against several bacteria and Candida strains. From the liquid chromatography-mass spectrometry (LC-MS) analysis, five polyphenolic compounds, namely digitoxigenin, digitonin glycoside and calactina in the leaves, kaempferol in the fruit, and calotropagenin in the stems, were identified. They were also analyzed for their drug likeliness, based on computational methods. Molecular docking study affirmed that the binding affinity of calactin and actodigin to the active site of TyrRS, topoisomerase type IIA, and SAP1 target virulence proteins was the highest among the examined dominant compounds. Therefore, this study indicated that P. tomentosa methanolic extracts displayed great potential to become a potent antimicrobial agent and might be a promising source for therapeutic and nutritional functions. These phytocompounds could be further promoted as a candidate for drug discovery and development
- …
