INFLUENCE DU TEMPS ET DU TAUX D’ACTIVATION DE LA BENTONITE SUR L’ADSORPTION DE L’ANILINE

L’objectif de cette étude est de déterminer les conditions optimales d’activation de la bentonite de Mostaghanem, au cours del’élimination d’un composé organique test, l’aniline. Nous avons traité la bentonite à l'acide sulfurique pour différents temps ettaux d'activation. Afin d’observer les effets d’un tel traitement sur les capacités d’adsorption de la bentonite, nous avonsdéterminé les paramètres d’équilibre et étudié les cinétiques des réactions. Les résultats de ces essais sont systématiquementcomparés à ceux obtenus en présence d’une bentonite brute, non traitée. Les meilleurs résultats concernant l’élimination del’aniline ont été obtenus pour un rapport acide/bentonite égal à 0,20 et un temps d’activation de 30 minutes

Geographic variation in phytochemical constituents and allelopathic potential of Pinus halepensis barks

Aqueous extracts (10, 20, 30 and 40 g/L) of Pinus halepensis barks, collected from Bizerte (B), Tabarka (T), Seliana (S) and Oueslatia (O) to elucidate the influence of ecological sites on allelopathic potential. Aqueous barks extracts from (S) and (O) have revealed a higher rate of phenolic acids than those from (T) and (B), respectively 13.23, 13.8, 11.63 and 10.37 mg/mL. Alep pin barks were analyzed using HPLC/UV for the identification and quantification of the phenolic compounds, among which in particular the catechin acetate, the gallic acid, the rutine hydrate, luteolin 7 glucoside and the cinnamic acid. In fact, the aqueous extract of barks from (S) revealed a highest level, respectively 2.61, 1.74, 1.61, 1.36, and 1.21 mg/mL. The Pinus halepensis barks was analyzed by GC and GC-MS. As a result, 29 compounds were identified representing 89% made up basically by β-caryophyllene, α-humulene. As for allelopathic activity, aqueous extracts of barks significantly delayed germination, reduced its rate and affected the seedling growth mainly the (S) and (O) extracts. The root growth of the two targets has shown a high sensibility compared to the shoot lengths. Pot cultures were conducted by the incorporation of barks powder (50 and 100 g/kg) or the irrigation with their aqueous extracts at 20 and 40 g/L. Pinus halepensis barks and its extracts have shown a high herbicide potent, particularly the one collected from (S) and (O), may be favorably used for incorporating in agricultural systems for sustainable weed managemen

EFFET DE LA MINERALISATION DES EAUX NATURELLES SUR L’ELIMINATION DE COMPOSES ORGANIQUES AROMATIQUES PAR COAGULATION-FLOCULATION THE EFFECT OF NATURAL WATER MINERALIZATION ON AROMATIC ORGANICS REMOVAL BY COAGULATION-FLOCCULATION

The purpose of this study is to observe the influence of the water mineralization on the removal by coagulation-flocculation of two different organic compounds, the humic substances and aniline. The experimental results showed that the process of flocculation is more effective towards the humic substances. The salt addition slightly improves aniline removal, contrary to the humic substances for which a clear improvement of efficiencies is observed. Compared with the tests in distilled water, the increase of concentration of inorganic salts in natural waters and in particular that of calcium or magnesium, clearly improved the removal of the humic substances. However, the efficiency of aniline flocculation seemed little affected.  Le présent travail a pour but d’étudier l’influence de la minéralisation d’une eau sur la coagulation-floculation par le sulfate d’aluminium de deux composés organiques différents, les substances humiques (SH) et l’aniline. Les résultats obtenus ont ainsi montré que le procédé de floculation est plus efficace vis-à-vis de l’abattement de composés de fortes masses moléculaires (SH). L’ajout de sels minéraux n’améliore que très légèrement l’abattement de l’aniline, contrairement aux (SH) pour lesquelles une nette amélioration des rendements est observée. Au cours de la dilution de ces composés organiques dans des eaux souterraines de minéralisations différentes, l’influence des éléments minéraux déjà observée en eau distillée a été confirmée. Les rendements d’élimination des SH se sont trouvés généralement fortement améliorés pour les eaux minéralisées. Par contre, l’efficacité de la floculation de l’aniline a semblé peu affectée et même amoindrie au fur et à mesure que la dureté des eaux augmentai

Biochemical characterization of a cefotaximehydrolysing &#946-lactamase encoded by a conjugative plasmid

During the nosocomials infections occurring in the intensive care unit of the military hospital of Tunis in 2005, the Enterobacter cloacae BW 1150 strain was isolated from a stool culture. This strain was found to have a high level resistance to broad-spectrum -lactams. Resistance profile against thevarious families of antibiotics was determined using the disc diffusion test. The minimal inhibitory concentrations values showed that this strain was resistant to the -lactams such as ampicillin and the extended spectrum cephalosporins (cefotaxime, ceftriaxon and cefpirome). Analysis of this strain by the disk diffusion test revealed synergies between amoxicillin-clavulanate (AMX-CA) and ceftriaxon, ceftazidime and cefotaxime. Cell sonicate of this isolate is very active against cefotaxime and showed aspecific activity (AS) of 7.54 U/mg for the same antibiotic. This activity was inhibited by the sulbactam and the clavulanic acid. Isoelectrofocusing methods revealed that the crude extract of the E. cloacae BW 1150 strain showed 1 - lactamase activity with an isoelectric piont (pI) of about 8. This activity was transferred by conjugation and was highly expressed in the transconjugant

Influence of Gravity on noncommutative Dirac equation

In this paper, we investigate the influence of gravity and noncommutativity on Dirac equation. By adopting the tetrad formalism, we show that the modified Dirac equation keeps the same form. The only modification is in the expression of the covariant derivative. The new form of this derivative is the product of its counterpart given in curved space-time with an operator which depends on the noncommutative $\theta$-parameter. As an application, we have computed the density number of the created particles in presence of constant strong electric field in an anisotropic Bianchi universe.Comment: 9 pages, correct some miprints, Accepted for publication in journal of Mod. Phys. Letters

Schottky Diodes and Thin Films Based on Copolymer: Poly(aniline-co-toluidine)

Poly(aniline-co-o-toluidine) (PANI-co-POT) thin films were deposited on indium tin oxide- (ITO-) coated glass substrates by electrochemical polymerization under cyclic voltammetric conditions from aniline-co-o-toluidine monomer in an aqueous solution of HCl as a supporting electrolyte. These measurements showed that the optical band gap of the copolymer films is on the order of 2.65 eV. On the other hand, ITO/PANI-co-POT/Al devices were fabricated by thermal evaporation of Aluminum circular electrodes on the as-deposited PANI-co-POT films. The Current-Voltage characteristics of these devices are nonlinear. The diode parameters were calculated from I-V characteristics using the modified Shockley equation. The C-F characteristics were also measured

Menopause and metabolic syndrome in Tunisian women

Objectives. This study aimed to evaluate the effect of menopausal status on the risk of metabolic syndrome (MetS) in Tunisian women. Methods. We analyzed a total of 2680 women aged between 35 and 70 years. Blood pressure, anthropometric indices, fasting glucose, and lipid profile were measured. The MetS was assessed by the modified NCEP-ATPIII definition. Results. The mean values of waist circumference, blood pressure, plasma lipids, and fasting glucose were significantly higher in postmenopausal than in premenopausal women, a difference that was no longer present when adjusting for age. Except for hypertriglyceridaemia, the frequency of central obesity, hyperglycemia, high blood pressure, and high total cholesterol was significantly higher in postmenopausal than in premenopausal women. After adjusting for age, the significance persisted only for hyperglycemia. The overall prevalence of MetS was 35.9%, higher in postmenopausal (45.7% versus 25.6%) than in premenopausal women. A binary logistic regression analysis showed that menopause was independently associated with MetS (OR = 1.41, 95% CI 1.10-1.82) after adjusting for age, residence area, marital status, family history of cardiovascular disease, education level, and occupation. Conclusions. The present study provides evidence that the MetS is highly prevalent in this group of women. Menopause can be a predictor of MetS independent of age in Tunisian women

Learning lessons from the 2011 Van Earthquake to enhance healthcare surge capacity in Turkey

Historically, Turkey has adopted a reactive approach to natural hazards which resulted in significant losses. However, following the 1999 Kocaeli Earthquake, a more proactive approach has been adopted. This study aims to explore the way this new approach operates on the ground. A multi-national and multi-disciplinary team conducted a field investigation following the 2011 Van Earthquake to identify lessons to inform healthcare emergency planning in Turkey and elsewhere. The team interviewed selected stakeholders including, healthcare emergency responders, search and rescue services, ambulance services, and health authority representatives, in addition to conducting a focus group. Data were analysed according to an open coding process and SWOT analysis. The findings suggest that the approach succeeded in developing a single vision by consolidating official efforts in a more structured way, mobilising many governmental and non-governmental organisations, securing significant amounts of resources including physical and human, and increasing the resilience and flexibility of infrastructure to expand its capacity. However, more attention is required to the development of stronger management procedures and acquisition of further resources

Transient deSUMOylation of IRF2BP proteins controls early transcription in EGFR signaling

Molecular switches are essential modules in signaling networksand transcriptional reprogramming. Here, we describe a role forsmall ubiquitin-related modifier SUMO as a molecular switch inepidermal growth factor receptor (EGFR) signaling. Using quantita-tive mass spectrometry, we compare the endogenous SUMOproteomes of HeLa cells before and after EGF stimulation. Thereby,we identify a small group of transcriptional coregulators includingIRF2BP1, IRF2BP2, and IRF2BPL as novel players in EGFR signaling.Comparison of cells expressing wild type or SUMOylation-deficientIRF2BP1indicates that transient deSUMOylation of IRF2BP proteinsis important for appropriate expression of immediate early genesincludingdual specificity phosphatase1(DUSP1, MKP-1) and thetranscription factor ATF3. We find that IRF2BP1is a repressor,whose transient deSUMOylation on the DUSP1promoter allows—and whose timely reSUMOylation restricts—DUSP1transcription.Our work thus provides a paradigm how comparative SUMOproteome analyses serve to reveal novel regulators in signal trans-duction and transcription