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This study assessed trace metal pollution in the Essaouira protected coastal area (Atlantic coast of Morocco) using the mussel Mytilus galloprovincialis as a bio-indicator and evaluated potential human health risks from mussel consumption. Samples were collected seasonally at 8:00 am from April 2017 to February 2018, and metal concentrations in mussel tissues were analyzed using ICP-AES. The metals were found in descending order: Fe > Zn > Al > Cu > Pb > Cr > Cd > Ag, with significant spatial and seasonal variations. Cluster analysis indicated different sources for the metals, with Fe, Zn, and Al linked to continental inputs and Cd, Cr, Pb, Cu, and Ag to anthropogenic sources. The pollution gradient, assessed using the Individual Multimetal Bioaccumulation Index (IMBI), showed that the area is less polluted than other Moroccan coasts. The Human health risk assessment revealed no significant risks, confirming the safety of mussel consumption from this region. [Display omitted] • Metal concentrations in mussels: Fe > Zn > Al > Cu > Pb > Cr > Cd > Ag. • Significant spatial and seasonal metal variations were observed. • Fe, Zn, Al have continental sources; Cd, Cr, Pb, Cu, Ag are urban/anthropogenic. • Essaouira's coastal area is less polluted than other Moroccan regions. • Mussel consumption from Essaouira is safe for human health, with no significant risks. [ABSTRACT FROM AUTHOR]

Nicotinic acetylcholine receptors are an important class of excitatory receptors in the central nervous system of arthropods. In the ticks Ixodes ricinus , the functional and pharmacological properties of nicotinic receptors located in their neurons are still unknown. The objective of this study was to characterize the pharmacological properties of tick nicotinic receptors using membrane microtransplantation in Xenopus laevis oocytes and two-electrodes voltage clamp method. The membranes microtransplanted were extracted from the tick synganglion. We found that oocytes microtransplanted with tick synganglion membranes expressed nicotinic acetylcholine receptor subtypes which were activated by acetylcholine (1 mM) and nicotine (1 mM). Currents induced by pressure application of acetylcholine and nicotine were diminished by 10 nM α-bungarotoxin and methyllycaconitine, suggesting that they expressed two subtypes of nicotinic receptors, α-bungarotoxin-sensitive and -insensitive, respectively. In addition, we found that nicotine receptors expressed in the synganglion membranes were poorly sensitive to the neonicotinoid insecticides clothianidin (CLT), imidacloprid (IMI), acetamiprid (ACE) and thiamethoxam (TMX), in agreement with their lack of activity as acaricides. Interestingly, current amplitudes were strongly potentialized in the presence of 1 μM PNU-120596. CLT was more active as an agonist than IMI, TMX and ACE. Finally, we demonstrated that microtransplantation of purified membrane from the tick synganglion can be a valuable tool for the development and screening of compounds targeting tick nicotinic acetylcholine receptor subtypes. Image 1 [ABSTRACT FROM AUTHOR]

In this work, we have successfully prepared the highly conducting and transparent Bi doped ZnO (BZO) thin films using pneumatic spray pyrolysis technique with nitrogen (N 2 ) carrier gas. The evolutions of structural, morphological and opto-electrical properties of the BZO films as a function of Bi concentration were analyzed. It is found that the films are uniform with no haze or visible clusters. X-ray diffraction shows that all the films were polycrystalline with hexagonal wurtzite structure, without secondary phases. All the BZO layers exhibit the classical preferential orientation of (002) plane and it changes in favor of (100) plane at 3 wt% Bi. The BZO thin films showed 83% as a value of average optical transmittance in the visible region. The optical band gap values oscillated around 3.23 and 3.27 eV. The SEM micrographs show clusters and nano-crystalline grains with special shape on the surface. The photoluminescence spectra of the films exhibits ultraviolet and green emissions. The electrical resistivity reaches a minimum value (8.4310 −3 Ωcm) at 1 wt% Bi. [ABSTRACT FROM AUTHOR]

Nowadays, water availability and quality represent a major challenge. In 2050, the United Nations Organization predicts that 44% of the world population will face severe water scarcity. Countries located in sub-humid and semi-arid regions of the world will be especially concerned for this problem, because of their low supply of rainwater. The aim of this study is to suggest the disinfection treatment by irradiation as a complement wastewater treatment to obtain a safe microbial quality of water and permit its reuse. This last is limited to 1.000 CFU/100 ml (i.e. equivalent to 3 log) of fecal coliforms by the Algerian and WHO standards. The experiments were conducted to disinfect wastewater by UVA, UVC, and solar radiation. The UVA and UVC disinfection treatments were carried out using an experimental bench composed of three flat-bottom flasks and three Erlenmeyers of 2 L each. The solar disinfection treatment was experimented using a 30 L-tubular photoreactor in a stationary and a dynamic flow. The disinfection results indicate a reduction in 2.47 log of total coliforms, 3 log reduction of fecal coliforms, 2.67 log reduction of streptococci, 3.17 log reduction of staphylococci, 0.08 log reduction of yeasts, 0.19 log reduction of molds, and a reduction of 1.17 log of sulfite-spores. [ABSTRACT FROM AUTHOR]

Wastewater treatment sector, in Algeria, uses exclusively two processes: the activated sludge applied in the north and the lagooning in the highlands and the south. In the operating balance of the National Sanitation Office (ONA), the activated sludge wastewater treatment plants are characterized by a high electricity consumption which induced high cost and greenhouse gas (GHG) emission. In 2010, about 104.32 million m3of wastewater was treated. This operation consumed 30,900 MWh of electricity which cost 1.04 million Euros (€) and emitted 18,761?tons of CO2-equivalent. In 2013, the treated wastewater increased by 35.2% and the electricity consumption by 45.8%. To establish an exhaustive diagnostic, this study evaluated the electricity consumed during 2009/2010 in an activated sludge wastewater treatment plant of 70,000 population equivalents (PE) (i.e. Unit of a pollution load produced daily per person, fixed at 60 grams of DBO5, which is used for the sizing of the wastewater treatment plants). Three areas were investigated: (1) the treatment process which consumed 89.63% of electricity; (2) the management department and the laboratory with 4.60%; and (3) the outdoor lighting with 5.77%. The biological treatment was the intensive-energy part of the treatment which consumed 70.05% of electricity. The aim of this diagnostic was to evaluate the performance level of the activated sludge wastewater treatment process relatively to the energy, financial and environmental factors in order to optimize the process and, then, to evaluate the benefit that could be provided by the integration of renewable energy in a sustainable wastewater treatment context. [ABSTRACT FROM PUBLISHER]

The wastewater reuse, especially for irrigation, requires a safer microbial quality. However, the tertiary treatment is often nonexistent, especially in developing countries where, unfortunately, wastewater treatment needs to be more systematic. Solar water disinfection processes could be appropriate treatments for improving the microbial quality of the wastewater reuse. This study evaluates the effectiveness of both solar photolysis and solar photocatalysis processes in disinfecting secondary-treated wastewater recovered from an activated sludge wastewater treatment plant where the disinfection treatment is not applied. The best parameters of the solar disinfection processes were determined. The experiments were conducted in a bench test composed of 4 flat-bottom flasks with a volume of 2 L each. Then, the disinfection efficiency of both processes was evaluated by a comparative study where 250 Wh/m² of UV radiation was cumulated. The disinfection efficiency of studied pathogenic (1) total coliforms, (2) fecal coliforms, (3) streptococci, (4) staphylococci, (5) sulfite-reducing spores, and (6) fungi ranged from 0.86-Log to 3.35-Log reduction. At last, an innovative static plan photoreactor of 50 L allowed reproducing the positive effect of the solar wastewater disinfection. After 8 h of solar exposure duration and a cumulative UV radiation of 360 Wh/m², results showed a complete disinfection of all studied pathogenic below the limit detection of the microbial analysis, except of sulfate-reducing spores. [ABSTRACT FROM AUTHOR]

In order to deepen the understanding of the main phenomena governing the membrane based energy recovery ventilators performance, we present a three dimensional numerical study of the mechanisms of heat and mass transfer in a cross-flow heat exchanger with balanced and unbalanced flow. This work involves the use of a control-volume method and solves the set of Navier–Stokes equations in the air streams and as well as in the membrane core. The results are compared to literature available data and the agreement is seen to be satisfactory. The effect of operating parameters such as the Reynolds number, volume flow rates and temperature on the performance of the heat exchanger are also investigated. [ABSTRACT FROM AUTHOR]

Highlights: [•] Partial blocks introduced in the gas channel improve the PEM fuel cell performance. [•] The effect of tilt angle is critical to the PEM fuel cell performance especially to minimize concentration over-potential. [•] Good agreement between computational and experimental data. [ABSTRACT FROM AUTHOR]

Abstract: With the aim of dynamic simulation and control, a new non-linear state-space dynamic non-isothermal polymer electrolyte membrane fuel cell (PEMFC) model is developed in this paper. This mathematical model is developed based on mass and energy equation. The present model takes in account subsequent factors as the effects of charge double layer capacitance, the geometrical capacity and the effect of temperature gradient. In this paper, the authors propose a combination of several dynamic equations to study the effect of suddenly variation of some operating parameters like load resistance, gas pressure and gas temperature input. The results are compared to those of an isothermal model. This model will be extremely functional for the best possible design and real-time control of PEMFC systems. The present model is executed in MATHCAD software and the fuel cell is symbolized by an equivalent circuit which incorporates gas diffusion layer, membrane and electrodes. The analysis results show that the main elements that influence the performance of the cell are load resistance and functioning temperature. [Copyright &y& Elsevier]

Résumé: But de l’étude: Le prolapsus rectal (PR) est une affection bénigne du jeune enfant et représente un motif de consultation fréquent en pédiatrie. Le but du travail est de faire le point sur la prise en charge du PR récidivant chez l’enfant et d’étudier la place de la sclérothérapie sous-muqueuse dans le traitement de cette pathologie. Patients et méthodes: Étude rétrospective concernant 15 enfants présentant un PR primitif et pris en charge pendant la période allant de 2002 à 2009. Le traitement des patients de cette série a consisté en une sclérothérapie périrectale sous-muqueuse, après échec du traitement médical. Résultats: Il s’agit de 15 patients d’un total de 25 n’ayant pas répondu au traitement médical. Les résultats à distance de la sclérothérapie ont été évalués après un recul de deux ans. La guérison a été obtenue dans 100 % des cas après une seule injection dans 14 cas et trois injections dans un seul cas. Aucune complication ni récidive n’ont été constatées. Conclusion: La sclérothérapie sous-muqueuse dans le traitement de PR primitif de l’enfant permet d’obtenir une guérison complète après une seule injection dans la majorité des cas. [ABSTRACT FROM AUTHOR]

Abstract: A two-dimensional computational fluid dynamics model of PEM fuel cell is developed by taking into account the electrochemical, mass and heat transfer process occurring in the cathode compartment. Additionally, this model includes the effect of water content in the membrane swelling phenomenon. Several parameters such as gases temperature, inlet velocity and membrane characteristics are too investigated to establish their effect on the PEM fuel cell performance. The membrane water content and the air fraction variation in the gas channel are examined for diverse values of Reynolds number. In particular, the desirable inlet flow for enhancing the performance of the PEM fuel cell is determined by examining membrane water content patterns. The methodology in this study is useful to the control of water management and gas diffusion layer design. [Copyright &y& Elsevier]

Abstract: A numerical analysis is performed for the natural convection flow resulting from the combined buoyancy effects of thermal and mass diffusion in an inclined cavity. This work enters within the framework of general study dealing with the mathematical model for solar brackish water desalination unit. The problem is stated in a Cartesian coordinates system, involves the use of a control volume-based finite-element method and solves the full vorticity transport equation together with the stream function, concentration and energy equations. The predicted stream function patterns, isoconcentration and isotherms are presented for different thermal Rayleigh numbers. The heat and mass transfer evolution are explained in terms of dynamic and temperature fields of the flow in the inclined cavity. In particular, the desirable flow for enhancing the performance of the solar distiller is determined by examining flow patterns. [Copyright &y& Elsevier]

Abstract: Intestinal Atresia is generally caused by intrauterine vascular obstructions. Intrauterine intussusception is one of these disruptive events. Intestinal intussusception is a disease that affects children commonly between 3 months and 3 years old in 90% of cases. There are few clinical cases in literature that demonstrate relationship between antenatal intussusceptions and ileal atresia. We report the case of a newborn with neonatal occlusion, where the surgical exploration revealed a Type 3A ileal atresia owing to antenatal ileoileal intussusception. [ABSTRACT FROM AUTHOR]

L’atrésie colique est la moins fréquente des atrésies de l’appareil digestif. Le trouble de vascularisation anténatal est l’hypothèse étiologique la plus communément admise pour expliquer les atrésies complètes. cette anomalie peut être isolée ou faire partie d’un syndrome poly malformatif. Nous rapportons rétrospectivement trois observations de nouveau-nés pris en charge entre 2002 et 2007 présentant une atrésie colique. Le premier cas est un nouveau-né de sexe féminin, ayant un syndrome de Prune-Belly hospitalisée à j2 de vie pour occlusion néonatale. L’exploration chirurgicale a constaté une atrésie colique complète du tiers droit du transverse, unique. Il a été réalisé une anastomose termino-terminale. En post opératoire l’enfant est décédé suite à un sepsis grave. Le deuxième cas est un nouveau-né de sexe masculin hospitalisé à j2 de vie pour occlusion néonatale. L’exploration chirurgicale a constaté l’existence d’un diaphragme colique complet à 10cm du cul de sac de douglas. Il a été réalisé une anastomose termino terminale et une colostomie droite transverse. La colostomie a été fermée à l’âge de 5 mois. il a développé à l’âge de 7 mois un ictère dont l’exploration a trouvé un kyste du cholédoque et a eu a l’âge de 2 ans une anastomose bilio-digestive avec des suites opératoires simples. Le troisième cas est un nouveau-né de sexe féminin admis à j2 de vie pour occlusion néonatale. L’exploration chirurgicale a trouvé une atrésie colique complète à 3 cm de la valvule de Bauhin, isolée. Il a été réalisé une colostomie de proche amont. La continuité digestive a été rétablie à l’âge de 5 mois avec conservation de la valvule. Dans les suites opératoires, elle a eu une fistule colique dirigée qui s’est tarie spontanément. Conclusion: A la lumière des ces observations et après une revue de la littérature, nous soulignons la rareté de l’atrésie colique complète, l’existence d’association malformative et le caractère exceptionnel de l’atrésie colique diaphragmatique non expliqué par la théorie de l’accident vasculaire. [Copyright &y& Elsevier]

The total heat exchanger is a promising technology used to recover both latent and sensible heat. An experimental setup was built in order to evaluate parametric effects on the total heat exchanger efficiency. Numerically, the physical problem involves a two dimensional model including the momentum, heat and mass transport equations in climate chamber submitted to a fresh air stream. The impact of air flow velocity on the heat and mass transfer distributions are experimentally and numerically established. The results show that the air temperature inside the climate chamber decreases from 19.5 to 17.6 °C when the air flow velocity increases from 0.125 m s −1 to 0.25 m s −1 . The surface of membrane has a great impact on the temperature and humidity profiles inside climate chamber when the membrane surface is sufficiently large. Complex phenomena such activation and clogging of membrane are discussed. The variation of membrane surface and/or flow velocity has an important impact on the activation and clogging times. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a numerical modeling, provides an improved understanding of the fundamental transport phenomena inside the PEM fuel cell. The problem is stated in a steady-state, two-dimensional model and Cartesian coordinates system by using a single domain and a control volume method. The model consists of non-linear, coupled partial differential equations representing the conservation of mass, momentum, species, charges and energy with electrochemical reactions that are valid for gas diffusion electrodes, catalyst layers and membrane region. The modeling of bidirectional, non-isothermal and steady problem of PEMFC provides results concerning the species fraction, potential and temperature distribution in different domain. [Copyright &y& Elsevier]

Abstract: NaX zeolite, Algerian bentonite, their mixtures, and their Cs-exchanged forms are subjected to heat treatment at different temperatures (800, 1000, and 1100°C) and γ-irradiation doses varying from 100 to 1000kGy. The effects of these treatments on structural and textural properties of the above materials as getters of radionuclides are studied using powder X-ray diffraction (XRD), nitrogen adsorption surface analyzer, and scanning electron microscopy (SEM). A thermal treatment of NaX and CsNaX zeolites up to 1000°C results in the formation of new crystalline phases (nepheline and carnegieite). In contrast, bentonite becomes totally amorphous when it is heat treated up to 800°C. Heat treating of zeolite–bentonite mixtures gives rise to partial amorphisation. γ-Irradiation of the studied materials reveals a good resistance of the Cs exchanged NaX zeolite. This is due to its higher basic character resulting from the Cs2O formed by the reaction between Cs+ present in the zeolite and the O2− anion liberated after γ-irradiation. [Copyright &y& Elsevier]

Abstract: Objective: To determine the incidence of catheter-related bacteremia (CRB) in a Moroccan medical intensive care unit, the microbiological profile of this infection and risk factors associated with its occurrence. Study design: Prospective observational study. Methods: Over a period of 8 months, patients who required central venous catheter (CVC) placement for a duration greater than 48h were included in the study. The CRB has been defined by the criteria of the SRLF Consensus Conference. The proportions of colonization and CRB were expressed as incidence density (ID). Risk factors for colonization were studied in univariate analysis. Results: One hundred and two CVC were inserted in 70 patients. The average age was 54±20 years with an APACHE II of 28±10. The ID of colonization and CRB were respectively 34 for 1000 days of CVC use and 8 for 1000 days of CVC use. The isolated microorganisms were Gram-negative bacilli in 73 %, Gram-positive cocci in 22 % and finally yeast in 5 %. A prolonged duration of catheterization and the absence of systemic antibiotic therapy before catheterization were the main risk factors for colonization. Conclusion: The incidence of CRB was high. These results impose a reflection of the care team to improve protocols for prevention of such nosocomial infections. [Copyright &y& Elsevier]

The desiccant liquid air membrane energy exchanger is a promising technology used to recover both latent and sensible heat. In this paper, a numerical investigation is carried out to provide the optimal operating fluids properties as well as to enhance the exchanger performance. The physical problem involves a two dimensional model including the momentum, heat and mass transport equations in both air and desiccant liquid channels. The impact of air and desiccant liquid properties on the heat and mass transfer distributions is determined. Optimal values of inlet air and desiccant liquid properties are established. The thermal and mass fields inside desiccant liquid air membrane energy exchanger are numerically presented. This performance investigation provides a solution to improve the heat and mass transfer rates in the addressed membrane based technology. [ABSTRACT FROM AUTHOR]

La parasitose hydatique est une pathologie sévissant à l’état endémique en Afrique du nord. Bien que les localisations pulmonaires et hépatiquesre présentent 90 % des localisations, le kyste hydatique peut toucher n’importe quel organe. Nous rapportons dans ce travail rétrospectif 6 cas de localisations primitives rares de kyste hydatique observés entre 2002 et 2007. Six enfants ont présentés des localisations primitives rares de kyste hydatique. Il s’agit dans deux cas de kyste hydatique du rein ouvert dans les voies excrétrices, dans 3 cas de kyste hydatique pelvien retropéritonéal et dans un cas de kyste hydatique pancréatique. Les explorations radiologiques (échographie + TDM) n’ont pas trouvé d’autre localisation hydatique dans 4 cas, et la découverte a été concomittente avec une localisation pulmonaire et hépatique dans les 2 cas de kystes pancréatique et rénal. Le diagnostic de kyste hydatique a été retenu dans tous les cas sur l’aspect per-opératoire et l’examen histologique. Tous les enfants ont bénéficiés d’une stérilisation du kyste, avec aspiration et extraction de la membrane proligère. Conclusion: Devant une masse kystique intra abdominale dans un pays d’endémie, le diagnostic de kyste hydatique doit être évoqué en dépit du caractère exceptionnel de ces localisations. [Copyright &y& Elsevier]

Summary: Abnormalities of the male genitalia have increased in the last 2 decades in numerous developed countries and remain a frequent reason of consultation in pediatric surgery. The diagnostic spectrum is wide, and surgeons should pay particular attention to these abnormalities because of their potential psychological effect. Anatomically, these abnormalities can affect one of three parts of the penis. First, the foreskin may not be fully retracted. This is normal at birth and can be caused by prepuce adherents that can continue until adolescence. Today, true phimosis is treated with topical corticoids from the age of 3years. If medical treatment fails, a surgical procedure is required. Second, the urethra can be affected by hypospadia, which is the most frequent abnormality of the urethra. It is associated with ectopic urethral meatus, hypoplastic foreskin, and penis curvature. Its pathogenic background is not clearly understood. Surgery options differ according to the type of hypospadia and according to the surgeon''s experience. It is sometimes hard to deal with, especially in a perineal form, where genetic and hormonal studies are recommended. These interventions can lead to complications ranging from stenosis to fistula. Therefore, parents have to be informed of the benefits and risks of the surgical procedures. Epispadias is rare but more serious because of the increasing risk of urinary incontinence. Finally, abnormalities of the corpora cavernosa — often associated with hypospadias — can include penis curvature and micropenis, for which an endocrinological analysis is essential. [Copyright &y& Elsevier]

Introduction La chirurgie de la cataracte est le type de chirurgie le plus fréquent en chirurgie ophtalmologique [1] . Différentes techniques d’ALR sont utilisées. L’inconfort et l’analgésie incomplète restent les principales limites de cette technique. Pour pallier ces limites, différentes techniques de sédation ont été utilisées [2] . L’objectif de notre étude était de comparer l’effet du rémifentanil et de l’hydroxyzine sur le confort peropératoire dans la chirurgie de cataracte sous anesthésie topique (AT). Matériel et méthodes Étude prospective randomisée réalisée au bloc opératoire de l’hôpital militaire Med V de Rabat. Étaient inclus tous les patients prévus pour une chirurgie de la cataracte sous anesthésie topique. Étaient exclus les patients âgés de moins de 18 ans, refusant ou présentant une contre indication à l’AT. Pour chaque patient inclus étaient relevées : les caractéristiques démographiques (âge, sexe, IMC, classe ASA, antécédents de chirurgie sur l’autre œil), le coté à opérer et la durée de la chirurgie. Les patients inclus étaient randomisés en deux groupes : Groupe remifentanil (Gr : R) chez qui une sédation par le remifentanil était démarrée en mode anesthésie à objectif de concentration (cible : 1 ng/mL) après la réalisation de l’AT et groupe contrôle (Gr : H) chez qui une sédation par l’hydroxyzine en perfusion lente (1 mg/kg) était faite. L’intensité de la douleur per opératoire évaluée chez les patients en SSPI par l’échelle visuelle analogique (EVA) était le critère de jugement principal. La mobilité peropératoire, le niveau de sédation, la satisfaction du patient, du chirurgien, les variations hémodynamiques et respiratoire étaient les critères de jugement secondaires. Résultats Durant la période d’étude de 2 mois (juin 2013–juillet 2013), 80 patients étaient inclus. Les caractéristiques démographiques, la durée de chirurgie et le coté à opérer étaient comparables entre les deux groupes. La douleur peropératoire était plus intense dans le G : H par rapport au Gr : R avec une EVA à 4,3 ± 0,9 et 1,9 ± 0,5 respectivement ( p < 0,001).Treize patients ont présenté une mobilité gênante et 8 une mobilité très gênante dans le Gr : H contre 3 et aucun respectivement dans le Gr : R ( p < 0,001). Aucun score de Ramsay 3 et 4 n’ont étés notés dans le Gr : H contre 6 et 3 malades respectivement dans le Gr : R ( p = 0,009). Six malades ont présenté une bradycardie dans le Gr : H contre 11 dans le Gr : R ( p = 0,27).Trois cas d’hypotension ont été notés dans le Gr : H contre six dans le Gr : R ( p = 0,48). L’incidence des hypertensions et des tachycardies était comparable entre les deux groupes avec respectivement ( p = 0,09) et ( p = 0,12). Les patients du Gr : H étaient moins satisfaits que ceux du Gr : R ( p = 0,002). De même une faible satisfaction de l’équipe chirurgicale était notée dans le Gr : H par rapport au Gr : R ( p < 0,001). Un seul cas de désaturation était noté dans le Gr : R contre aucun dans le Gr : H. Discussion La sédation par le remifentanil permet un meilleur confort peropératoire par rapport à l’hydoxyzine au cours de la chirurgie de la cataracte sous anesthésie topique avec des effets indésirables tolérables. [ABSTRACT FROM AUTHOR]