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The effluent dairy industries are among the most organic-rich food waste. With high values of lactose, proteins, vitamins and minerals, it is a favorable medium for the growth of microorganisms such as fecal coliforms and streptococci. In addition, it has high levels of COD, total nitrogen and total phosphorus that indicates a significant pollution of the ecosystems where it is drained. This study focuses on the treatment of dairy effluent by two different methods. The first is a physicochemical treatment by coagulation, flocculation; using aluminum sulphate and sodium alginate. While the second process is a biological treatment using Pseudomonas fluorescens and Bacillus spp. The results show a decrease of about 30% of chemical oxygen demand, 49% of turbidity, 78% of suspended solids and 20% of the total phosphorus. The second process has shown a significant reduction of all parameters better than the physico-chemical treatment, with fluctuations in efficacy between the strains tested. In conclusion, we have developed biotechnological processes, which are simple, economical and environmentally friendly for treating the discharges of the dairy industry and reduce polluting factors, Journal of Applied Science and Environmental Studies, Vol 1, No 2 (2018)

In this work, we were interested in the valorization of dairy industry waste. The City of Rabat/Salè's Milk Processing Unit discharges approximately 7500 litres/day of whey daily. Due to its biochemical composition (lactose, proteins, vitamins), whey is an excellent recyclable medium and becomes a formidable pollution factor. Similarly, the production of bioethanol through the fermentation of dairy industry waste is very limited. The yield and alcohol tolerance of the organisms in the alcoholic fermentation of lactose from whey is very low. So the objective of this work is to produce fermentable monomeric sugars fermentable in ethanol from whey. This study proposes chemical treatments of whey to release glucose and galactose. Also, the experimental conditions were optimized and the results of chemical hydrolysis by carbon dioxide, sulphuric acid and hydrochloric acid were compared. This study made it possible to develop processes for valuing dairy industry waste using clean technologies by reducing factors as pollutants and for the production of fermentable molecules, Journal of Applied Science and Environmental Studies, Vol 1, No 2 (2018)

Direct contact membrane distillation (DCMD) process was applied for the treatment of textile dyes solutions using a flat-sheet polyvinylidene fluoride (PVDF) membrane. Both cationic (Maxilon Blue 5G, Drimarene Yellow K-2R) and anionic (Sodium Fluorescein) dyes have been considered. A model-type of a textile wastewater solution containing salts and the three cited dyes have also been tested to simulate real discharges of textile industries. The effects of DCMD operating parameters on the permeate flux and separation factor have been studied. Fouling phenomenon on both the membrane surface and in its pores was investigated by means of various characterization techniques and the permeate flux reduction factor together with the irreversible fouling index were determined. Different fouling mechanisms in DCMD could be established for each type of dye.

3 ABSTRACT: In this work, the decolorization of Methyl Orange was conducted using catalysts prepared by impregnation of copper on natural clay in the presence of H2O2. The catalysts Cu-clay, prepared from the concentrated metal precursor of (impregnation ratio, W(Cu(NO3)2)/W(clay) = 1,5%-7,5%) were characterized by several methods such as X-ray diffraction (XRD), electronic scan microscopy (SEM), x-ray fluorescence (FX), and Brunauer-Emmett- Teller (BET). Important factors affecting catalyst activity and methyl orange removal efficiencies were studied: the effects of temperature, oxidant concentration, and catalyst dosage. The results showed, a very significant activation of hydrogen peroxide by the catalyst, the Methyl Orange depletion percentage reaching 94 % after 2 h, and very stability of the catalyst. It was also observed that the best catalyst, at a reaction temperature of 25°C. 2,5ml of H2O2 and 4.0 g/L of 5% Cu-clay, 94% decolorization was achieved within 120 min treatment. Although the Cu show high activity, their stability and reusability still need improvement.

Le present travail a pour objectif le traitement des lixiviats de la decharge publique controlee de la ville de Fes par des procedes biologiques et chimiques. Une accumulation des metaux lourds par des micro-organismes aerobies specifiques presents dans le lixiviat reduit davantage les metaux lourds, principalement les ions Mn 2+ , avec un taux d’abattement compris entre 90,8% et 93,3%, et permet aussi une elimination totale des germes de contamination fecale (coliformes fecaux, streptocoques fecaux), des levures et des champignons.Ce traitement a entraine egalement une reduction de la demande chimique totale en oxygene (DCO T ) et la demande chimique en oxygene soluble (DCO S ), respectivement de 60% et de 88%. Le traitement anaerobie du lixiviat par fermentation pendant 48 heures a montre une reduction de la DCO T de 74%. Le traitement biologique par Sequencing Batch Reactor (SBR) a montre egalement des resultats permettant une reduction de 87% pour la DCO T et 96,77% pour la demande biologique en oxygene durant 5 jours (DBO 5 ). Le traitement chimique par coagulation-floculation, utilisant la chaux, le chlorure ferrique (FeCl36H2O) et le sulfate d’alumine (Al 2 (SO 4 )318H 2 O), reduit respectivement la DCO T de 36,6%, 81,67% et 85%. La coagulation-floculation avec 200 mg/L de FeCl 3 6H 2 O a montre une reduction des germes fecaux de plus de 85%. Le couplage du traitement chimique par coagulation-floculation au traitement biologique par SBR permet d’obtenir des resultats satisfaisants en matiere d’elimination des elements mineraux contenus dans les lixiviats et une reduction de la DCO T , de la DBO 5 et des polyphenols, respectivement de 98%, 99,16% et 94,53%.

Accurate assessment of diagnostic tests may be biased if an imperfect reference test is used for comparison; such a situation exists for the diagnosis of canine leishmaniasis. We compared classical diagnostic tests for Leishmania infantum with Latent Class Analysis (LCA), to assess whether we could make a more accurate calculation of diagnostic accuracy. Microscopy (Lymph node aspirate), serological test (IFAT), and molecular tests (LAMP and PCR) data were recorded for 75 dogs captured in Tunisian endemic area and suspected of leishmaniasis. Sensitivity and specificity estimates with the 2 x 2 contingency tables (Microscopy as gold standard) were broadly corroborated by LCA. However, the LCA provided a way to control the study limitations (small sample size) as well as for confounding factors. It also produces consistent estimates of the test characteristics. LCA estimation of the sensitivity and specifcity of the LAMP cpb assay (se: 68.7% [95% CI 573-80%] and sp: 86.2 [95% CI 749-975%]) is higher as compared to classical calculations (se: 54.2% [95% CI 38.2-69.5%] and sp: 80% [95% CI 65.2-89.5%). Considering the lack of an adequate reference standard, LCA proved to be a useful tool to independently evaluate diagnostic methods.

The properties of polarons and bipolarons are studied by the variational method taking into account the density of state for Van Hove singularity (V.H.S) in two-dimension (2D) in the presence of a perpendicular magnetic field. It should be noticed that the bipolaron stability region is relatively sensitive to the application of a magnetic field. In 2D, for ωc = 0.8 the value of αc = 1 is compared to αc = 1.6 for ωc = 0. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The impurity binding energy in the absence and in the presence of honfined LO-phonon interaction in a cubic quantum dot for several values of the mass ratio λ and for several heights of the barrier has been calculated using a variational approach. The quantum confinement is described by a finite potential well. The charge carrier (electron and ion)-phonon coupling is treated within the adiabatic approximation. The results show that this effect increases, reaches a peak value and then decreases as the dot size increases and depends strongly on the impurity position. The confined LO-phonon effect decreases by displacing the impurity from the center to the dot boundary.

The ion exchange of hydrogenophosphate ion in Zn–Al–chloride layered double hydroxides was investigated. The chloride precursors prepared by coprecipitation at pH 10 preserved their lamellar structure following ion exchange. It was found that the aging time is important in controlling the crystallization of the phosphate-exchanged compounds; long aging times of more than 8 h lead to poorly crystallized phases. The grafting of the anion onto hydroxylated sheets by moderate thermal treatment was confirmed by a combination of several techniques, including powder X-ray diffraction (XRD), infrared (IR) spectroscopy, and thermal analyses.

The ion exchange of chloride by hydrogenophosphate in the [Zn–Al–Cl] layered double hydroxide was investigated by using X-ray diffraction and infrared spectroscopy. The effects of [Zn2+/[AI3+] ratio in [Zn–Al–Cl], anion concentration in the solution, aging time and temperature of the solution on the ion exchange were studied. The best sample in terms of crystallinity and extent of ion exchange was obtained by carrying out the exchange reaction at 25°C in a 0.01 M HPO42− solution at pH 8 with at least 5 h of aging time. A sample prepared under these conditions was further characterized by X-ray microanalysis.

Summary The synthesis of zinc-chromium Lamellar Double Hydroxides (LDHs) intercalated by sulfate anions was carried out using three synthetic methods. The combination of coprecipitation and anionic exchange in one stage allows to prepare the well organised [Zn-Cr-SO 4 ] LDHs. Depending on pH conditions and washing process the sulfate intercalated LDH exhibits two 2H hexagonal varieties with different layer spacings d≈8.9A and d≈HA at room temperature; this latter with superstructure was related to the insertion of the alkaline interlamellar cations.

Primary adhalin (or alpha-sarcoglycan) deficiency due to a defect of the adhalin gene localized on chromosome 17q21 causes an autosomal recessive myopathy. We evaluated 20 patients from 15 families (12 from Europe and three from North Africa) with a primary adhalin deficiency with two objectives: characterization of the clinical phenotype and analysis of the correlation with the level of adhalin expression and the type of gene mutation. Age at onset and severity of the myopathy were heterogeneous: six patients were wheel-chair bound before 15 years of age, whereas five other patients had mild disease with preserved ambulation in adulthood. The clinical pattern was similar in all the patients with symmetric characteristic involvement of trunk and limb muscles, calf hypertrophy, and absence of cardiac dysfunction. Immunofluorescence and immunoblot studies of muscle biopsy specimens showed a large variation in the expression of adhalin. The degree of adhalin deficiency was fairly correlated with the clinical severity. There were 15 different mutations (10 missense, five null). Double null mutations (three patients) were associated with severe myopathy, but in the other cases (null/missense and double missense) there was a large variation in the severity of the disease.

The synthesis of zinc–chromium lamellar double hydroxides (LDHs) intercalated by sulfate anions is carried out with a one-step method that combines coprecipitation and anionic exchange. The materials obtained in a reactor containing a sodium sulfate solution are compared with those prepared from lithium, potassium, and ammonium sulfate solutions. The compounds are characterized by chemical analysis, powder X-ray diffraction, and infra-red spectroscopy. Depending on pH conditions, the washing process, and the nature of the monovalent cation, the sulfate intercalated compounds exhibit two 2H hexagonal varieties with different layer spacings d ≈8.9 A and d ≈11 A at room temperature; this last phase is related to the insertion of alkaline interlamellar cations. Under dry air, the loss of intercalated water leads to a 3R rhombohedral variety with d ≈8.2 A. A second rhombohedral variety with d ≈10.9 A is reversibly obtained from the “8.9 A” phase under high relative humidity. These four [Zn–Cr–SO 4 ] LDHs differ by their stacking sequences and interlamellar distances and can be selectively obtained.

Thin films of lead titanate were prepared in-situ using radio-frequency magnetron sputter-deposition. The in-situ perovskite phase formation has been studied as a function of the substrate material, the substrate temperature (TS) and the sputtered lead flux. The incident lead flux is controlled by the lead content in the target (X). Perovskite phase can be obtained under a relatively wide range of sputtering conditions with control of the Pb content in the film. The formation temperature of the perovskite phase increased when the incident Pb flux increased. With an appropriate combination of TS and X, it is possible to grow, at relatively low temperature, stoichiometric thin films compatible with semi-conductor substrates. For example, PbTiO3 films have been deposited on silicon and gallium arsenide substrates at 440°C; these films present ferroelectric properties.

Summary Autosomal recessive forms of axonal Charcot‐Marie‐ Tooth (ARCMT2) disease are frequent in some areas, such as North Africa and the Middle East, since consanguineous marriages are still common there. Recently, a unique homozygous mutation in LMNA, which encodes lamin A/C, a component of the nuclear envelope, was identified in members of three Algerian families with ARCMT2 linked to chromosome 1q21.2-q21.3. In the present study we describe a group of 21 ARCMT2 patients from seven unrelated Algerian families with the same R298C mutation in the lamin A/C gene and marked variability of the clinical phenotype. There is a wide range of age of onset, from 6 to 27 years, with a mean of 14.4 6 4.6 years. The course of the disease varies considerably from one patient to another. Twelve patients with a disease duration of 10‐15 years had a severe CMT phenotype with distal wasting and weakness of all four limbs and areflexia associated with involvement of the proximal lower limb muscles. In contrast, nine patients had the classical CMT phenotype with mild functional disability without proximal lower limb involvement after a disease duration of 5‐18 years. Electrophysiological studies showed a median motor nerve conduction velocity (MNCV) in the normal range in almost all the patients. MNCV and compound muscle action potential (CMAP) values were inversely correlated with the disease duration and the MNCV was strictly related to the CMAP, strongly supporting a pure axonal process without a demyelinating component. Six patients had a nerve biopsy, which revealed severe rarefaction of myelinated fibres in all cases and an increased density of unmyelinated fibres in the majority of cases. In conclusion, the ARCMT2 associated with the R298C mutation differs from other types of ARCMT2. The variability among patients in the age of onset and the course of the disease strongly suggests the action of modifying genes, which remain to be identified.

Marked deficiency of muscle adhalin, a 50 kDa sarcolemmal dystrophin-associated glycoprotein, has been reported in severe childhood autosomal recessive muscular dystrophy (SCARMD). This is a Duchenne-like disease affecting both males and females first described in Tunisian families. Adhalin deficiency has been found in SCARMD patients from North Africa Europe, Brazil, Japan and North America (SLR & KPC, unpublished data). The disease was initially linked to an unidentified gene on chromosome 13 in families from North Africa, and to the adhalin gene itself on chromosome 17q in one French family in which missense mutations were identified. Thus there are two kinds of myopathies with adhalin deficiency: one with a primary defect of adhalin (primary adhalinopathies), and one in which absence of adhalin is secondary to a separate gene defect on chromosome 13. We have examined the importance of primary adhalinopathies among myopathies with adhalin deficiency, and describe several additional mutations (null and missense) in the adhalin gene in 10 new families from Europe and North Africa. Disease severity varies in age of onset and rate of progression, and patients with null mutations are the most severely affected.

X-LINKED recessive Duchenne muscular dystrophy (DMD) is caused by the absence of dystrophin, a membrane cytoskeletal protein1,2. Dystrophin is associated with a large oligomeric com-plex of sarcolemmal glycoproteins3–10. The dystrophin–glycoprotein complex has been proposed to span the sarcolemma to provide a link fyetween the subsarcolemmal cytoskeleton and the extracellular matrix component, laminin7,9. In DMD, the absence of dystrophin leads to a large reduction in all of the dystrophin-associated proteins4,9,10. We have investigated the possibility that a deficiency of a dystrophin-associated protein could be the cause of severe childhood autosomal recessive mus-cular dystrophy (SCARMD) with a DMD-like phenotype11–14. Here we report the specific deficiency of the 50K dystrophin-associated glycoprotein (Mr 50,000) in sarcolemma of SCARMD patients. Therefore, the loss of this glycoprotein is a common denominator of the pathological process leading to muscle cell necrosis in two forms of muscular dystrophy, DMD and SCARMD.