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Abboussi O.,Hassan 1er University | Paizanis E.,University of Caen Lower Normandy | El Ganouni S.,Hassan 1er University
Pharmacology Biochemistry and Behavior | Year: 2014

Several epidemiological studies show an increase in cannabis use among adolescents, especially in Morocco for being one of the major producers in the world. The neurobiological consequences of chronic cannabis use are still poorly understood. In addition, brain plasticity linked to ontogeny portrays adolescence as a period of vulnerability to the deleterious effects of drugs. The aim of this study was to investigate the behavioral neurogenic effects of chronic exposure to the cannabinoid agonist WIN55,212-2 during adolescence, by evaluating the emotional and cognitive performances, and the consequences on neurogenesis along the dorso-ventral axis of the hippocampus in adult rats. WIN55,212 was administered intraperitoneally (i.p.) once daily for 20 days to adolescent (27-30 PND) and adult Wistar rats (54-57 PND) at the dose of 1 mg/kg. Following a 20 day washout period, emotional and cognitive functions were assessed by the Morris water maze test and the two-way active avoidance test. Twelve hours after, brains were removed and hippocampal neurogenesis was assessed using the doublecortin (DCX) as a marker for cell proliferation. Our results showed that chronic WIN55,212-2 treatment significantly increased thigmotaxis early in the training process whatever the age of treatment, induced spatial learning and memory deficits in adolescent but not adult rats in the Morris water maze test, while it had no significant effect in the active avoidance test during multitrial training in the shuttle box. In addition, the cognitive deficits assessed in adolescent rats were positively correlated to a decrease in the number of newly generated neurons in dorsal hippocampus. These data suggest that long term exposure to cannabinoids may affect more potently spatial learning and memory in adolescent compared to adult rats via a negative action on hippocampal plasticity. © 2014 Elsevier Inc.

Barka N.,Hassan 1er University | Abdennouri M.,Hassan 1er University | El Makhfouk M.,British Petroleum | Qourzal S.,University Ibn Zohr
Journal of Environmental Chemical Engineering | Year: 2013

The biosorption of cadmium (II) and lead (II) ions onto a natural, plentiful and low-cost biosorbent developed from cactus cladodes was investigated in batch mode. Experiments were carried out as a function of average biosorbent particle size, pH, biosorbent mass, contact time, initial metal concentration and temperature. The experimental results indicate that, the percentage of biosorption increases with an increase in the biosorbent dosage and the decrease of particle size. The equilibrium uptake was increased with an increase in the initial metal concentration in solution. The maximum biosorption occurred at pH of 5.8 and 3.5, respectively for cadmium (II) and lead (II) ions. Biosorption kinetic data were properly fitted with the pseudo-second-order kinetic model. The equilibrium data fitted very well to the Langmuir model with a maximum monolayer biosorption capacity of 30.42 and 98.62 mg/g, respectively for cadmium (II) and lead (II) ions. The biosorption yield decreases with an increase in solution temperature. The FTIR analysis of unloaded and metal loaded biosorbent indicated the involvement of CO, OC and COC groups in metal binding. © 2013 Elsevier Ltd. All rights reserved.

Barka N.,Hassan 1er University | Abdennouri M.,Hassan 1er University | Makhfouk M.E.,British Petroleum
Journal of the Taiwan Institute of Chemical Engineers | Year: 2013

The biosorption of Methylene Blue (MB), Eriochrome Black T (EBT) and Alizarin S (AS) from aqueous solutions by dried prickly pear cactus cladodes as a low-cost, natural and eco-friendly biosorbent was investigated. The study was carried out under various parameters, such as average biosorbent particle size, pH, biosorbent dosage, contact time, initial dye concentration and temperature. The experimental results show that, the percentage of biosorption increases with an increase in the biosorbent dosage, and the decrease of particle size. The biosorption was pH dependent with a high biosorption of cationic dye (MB) in basic range and a high biosorption of anionic dyes (EBT and AS) in acidic range. The equilibrium uptake was increased with an increase in the initial dye concentration in solution. Biosorption kinetic data were properly fitted with the pseudo-second-order kinetic model. The experimental isotherm data were analyzed using Langmuir, Freundlich, Redlich-Peterson, Temkin and Toth isotherm equations. The best fit was obtained by the Redlich-Peterson model and the Langmuir model with a Langmuir maximum monolayer biosorption capacity of 189.83. mg/g for Methylene Blue, 200.22. mg/g for Eriochrome Black T and 118.35. mg/g for Alizarin S. The biosorption was exothermic in nature (ΔH° = -31.035 kJ/mol for MB, -10.25 kJ/mol for EBT and -11.69 kJ/mol for AS). The reaction was accompanied by a decrease in entropy (ΔS° = -94.76 J/K mol for MB, -38.44 J/K mol for EBT and -41.93 J/K mol for AS). The Gibbs energy (ΔG°) increased when the temperature was increased from 25 to 60. °C indicating a decrease in feasibility of biosorption at higher temperatures. © 2012 Taiwan Institute of Chemical Engineers.

Manoun B.,Hassan 1er University | Igartua J.M.,University of the Basque Country | Lazor P.,Uppsala University | Ezzahi A.,Hassan 1er University
Journal of Molecular Structure | Year: 2012

In this paper we report high-temperature (up to 550 °C) Raman spectroscopy of phase transitions in Sr2MWO6 (M = Zn, Co) double perovskite oxides. For Sr2ZnWO6 modes centered at 137 cm-1, 152 cm-1, merge around 80 °C. The same behavior was observed for the 436 cm-1 and 447 cm-1 modes. The mode centered at 854 cm-1 shows a change in the slope at the same temperature, thus indicating a first order phase transition from the monoclinic (P21/n) to tetragonal (I4/m) structure. With increasing temperature, a little change in the slope of the temperature dependence of mode centered at 855 cm-1 is observed around 480 °C which might be a sign of the second phase transition in Sr2ZnWO6 (tetragonal (I4/m) to cubic (Fm-3m)). The temperature dependence of the full width at half maximum (FWHM) of the most intense modes in Sr 2ZnWO6 spectra was studied. The width behaves linearly as a function of temperature with a break observed in the slope of the width of the modes at 80 °C; thus, showing the first phase transition occurrence. For Sr2CoWO6 the transition from tetragonal (I4/m) structure to cubic (Fm-3m) phase is accompanied by considerable changes in the temperature dependence of modes centered at 438 cm-1 and 845 cm-1. The transition was observed around 420 °C. © 2012 Elsevier B.V. All rights reserved.

Manoun B.,Hassan 1er University | Tamraoui Y.,Hassan 1er University | Lazor P.,Uppsala University | Yang W.,Carnegie Institution of Washington | Yang W.,HIGH-TECH
Applied Physics Letters | Year: 2013

Double-perovskite oxide Sr2MgTeO6 has been synthetized, and its crystal structure was probed by the technique of X-ray diffraction at room temperature. The structure is monoclinic, space group I2/m. Temperature-induced phase transitions in this compound were investigated by Raman spectroscopy up to 550 °C. Two low-wavenumber modes corresponding to external lattice vibrations merge at temperature of around 100 °C, indicating a phase transition from the monoclinic (I2/m) to the tetragonal (I4/m) structure. At 300 °C, changes in the slopes of temperature dependencies of external and O-Te-O bending modes are detected and interpreted as a second phase transition from the tetragonal (I4/m) to the cubic (Fm-3m) structure. © 2013 AIP Publishing LLC.

Tajeddine L.,Hassan 1er University | Mountacer H.,Hassan 1er University | Sarrakha M.,University Blaise Pascal
Arabian Journal of Chemistry | Year: 2010

Photochemistry studies can be helpful in assessing the environmental fate of chemicals. For this reason, the photodegradation kinetic studies of the two pesticides orthophenylphenol (OPP) and monuron, largely used in agriculture, were carried out in solid phase. The fungicide OPP and the herbicide monuron were irradiated on the clay fractions (montmorillonite and modified clays) using a suntest simulator. The phototransformation of the parent compound was followed by HPLC technique. The photodegradation process appears to follow the first order reaction. Kinetic parameters were determined and the experimental results show that the photodegradation of these substrates was enhanced in presence of K-montmorillonite, in comparison with Fe(III) exchanged montmorillonite and montmorillonite complexed with humic acid complexes. This study has shown that the iron and humic acid adsorbed on clay surfaces did not increase the degradation rate. © 2010.

Jebbouj R.,Hassan 1er University | El Yousfi B.,French National Institute for Agricultural Research
European Journal of Plant Pathology | Year: 2010

Knowledge of pathotype diversity and virulence in local populations of Pyrenophora teres is a prerequisite to screening for durable resistance to net blotch. The current study aimed to quantify the virulence level of Moroccan isolates, identify and designate existing pathotypes, and select resistant genotypes. We developed a method for virulence quantification of P. teres isolates based on a conversion of infection responses into frequencies for use in correspondence analysis. Coordinates of the first axis of this analysis had a virulence spectrum and ranked isolates from virulent to avirulent. Mixed model analysis was also devised for virulence quantification. Coordinates of the first dimension of correspondence analysis were linearly correlated to BLUPs (Best Linear Unbiased Predictors) of the mixed model. A genotype by genotype by environment model (GGE) coupled with cluster analysis differentiated P. teres isolates into ten and nine pathotypes for net- and spot-forms respectively. Populations of these two forms were dissimilar in terms of classes of virulence. For P. teres f. maculata, avirulent, moderately virulent and highly virulent isolates represented one-third of the population, whereas 90% of P. teres f. teres population was composed of avirulent to moderately avirulent isolates. Barley differential sets were subsequently reduced to two new sets that simplified pathotyping through a key code based on resistant or susceptible reactions. Dendrograms of cluster analysis based on GGE analysis depicted the stability of a genotype's reactions across all isolates, and using only resistant cultivars as sources of resistance to control net blotch disease would, based on this analysis, fail to control all pathotypes. Therefore, we propose an alternative breeding strategy to control net blotch effectively. © 2010 KNPV.

El Majdoub K.,Hassan II University | Ouadi H.,Hassan II University | Touati A.,Hassan 1er University
International Review on Modelling and Simulations | Year: 2014

This paper discuss the problem of controlling quarter-car semi-active suspension system. Presently, the suspension system involves a magnetorheological (MR) damper with a hysteretic behavior captured through the Bouc-Wen model. This device can be integrated in the electric or hybrid electric vehicle. The control objective is to regulate well the chassis vertical position despite the road irregularities. In addition to these irregularities, the difficulty of the control problem lies in the nonlinearity of the system model and the inaccessibility to measurements of the hysteresis internal state variable. The control design is performed using the LQR theory and Lyapunov control design tools; it includes an observer providing online estimates of the hysteresis internal state. The controller is formally shown to meet the desired control objectives. This theoretical result is confirmed by several simulations. The latter illustrate the performances of the LQR method and compare them with those of the passive suspension. © 2014 Praise Worthy Prize S.r.l. - All rights reserved.

Lahrich S.,Hassan 1er University | Manoun B.,Hassan 1er University | El Mhammedi M.A.,Hassan 1er University
Talanta | Year: 2016

In this paper, we report a synthesis of a new lacunar apatite, KCdPb3(PO4)3, using solid state method, and its application as modifier of carbon paste electrode (KLA-CPE) to determine mercury (II). Sodium replacement with potassium induced a linear variation of the crystallographic parameters a and c according to Vegard's law and led to amplify the electrical signal of the working electrode. The peak currents of mercury (II) increased linearly with their concentration at the range from 2.0×10-7 mol L-1 to 1.0×10-4 mol L-1 using differential pulse anodic stripping voltammetry. The detection limit was found to be 1.11×10-8 mol L-1. The use of this electrochemical sensor has been successfully implemented for the determination of Hg (II) in seawater and fish samples. The obtained results were found to be very satisfactory. © 2015 Elsevier B.V. All rights reserved.

Chahhou M.,University Sidi Mohammed Ben Abdellah | Moumoun L.,Hassan 1er University | Far M.E.,University Sidi Mohammed Ben Abdellah | Gadi T.,Hassan 1er University
IEEE Transactions on Pattern Analysis and Machine Intelligence | Year: 2014

In this paper, we propose a new approach to get the optimal segmentation of a 3D mesh as a human can perceive using the minima rule and spectral clustering. This method is fully unsupervised and provides a hierarchical segmentation via recursive cuts. We introduce a new concept of the adjacency matrix based on cognitive studies. We also introduce the use of one-spectral clustering which leads to the optimal Cheeger cut value. © 1979-2012 IEEE.

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