1,425 research outputs found

    Traitements d'effluents issus de l'industrie de la pêche par un procédé de coagulation/floculation

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    La présente étude porte sur le traitement physico-chimique d'un effluent industriel chargé d'encre de seiche issu de l'industrie de conditionnement des produits de la pêche. Différentes combinaisons de coagulant -floculant ont été étudiées. Le sulfate d'aluminium (SA), divers polyélectrolytes et certains adjuvants pulvérulents ont été utilisés. L'efficacité du traitement par coagulation-floculation a été analysée en suivant l'évolution de la turbidité et de la DCO résiduelle du surnageant.Les résultats de cette étude ont révélé qu'à pH 6-7, l'addition de SA à une concentration supérieure à 1000 mg.l-1 entraîne la coagulation des particules d'encre de seiche. L'addition d'un polyélectrolyte en association avec le SA permet de réduire la concentration requise en SA à environ 300 mg.l-1, tout en améliorant l'efficacité du processus de coagulation-floculation. Le recours à un adjuvant pulvérulent en combinaison avec le SA et un polyélectrolyte accroît notablement les performances du traitement et permet d'obtenir un effluent ayant une turbidité résiduelle de 7 NTU.The aim of this work was to compare the efficiency of a coagulation-flocculation process using different systems individually or in combination. The waste water used was an industrial cuttlefish effluent principally composed of colloidal particles from the cuttlefish. The initial turbidity and chemical oxygen demand were approximately 700 NTU and 22,000 mg×L-1 respectively. Two parameters were used to assess the process efficiency: the residual turbidity and the chemical oxygen demand (COD) of the supernatant.Three systems were investigated: aluminium sulphate (SA), polyelectrolytes and a ternary combination of SA-polyelectrolyte and colloidal microparticle adjuvant. Results demonstrated that at pH 6-7, SA caused some coagulation of the suspension, but the dosage required (about 1000 mg×L-1) far exceeded those conventionally used in water treatment. As a consequence, an appreciable amount of SA, which was above the authorised limits, remained in the supernatant. Indeed, adsorption isotherm measurements revealed that at pH 6.5-7 the residual proportion of SA attained was about 20%. The addition of polyelectrolytes in combination with SA allowed reduction of the SA dosage to 150 mg×L-1. Amongst the polymers tested, the cationic polymer was the most efficient. The ability to bring about flocculation was positively related to the molecular weight, which is in agreement with a bridging flocculation mechanism. Starch, a natural, low-cost polymer was also an efficient flocculent even though it is a non-charged polymer. The ability of starch to bring about a flocculation action was explained by its relatively low solubility, which leads to some aggregation of macromolecular chains that act as anchoring sites for the coagulated ink particles. With this system, a double treatment in the presence of 150 mg×L-1 SA and 25 mg×L-1 polydiallyldimethylammonium chloride (PDMAC) or starch lead to a supernatant with a turbidity and COD of 150 NTU and 5500 mg×L-1 respectively.The third part of our study was concerned with the effect of the addition of an insoluble microparticle adjuvant in combination with SA and polyelectrolytes. Different components were investigated, but among them only colloidal silica and MgO bring about a significant enhancement of the flocculation process. This effect was explained by a bridging mechanism in which the adjuvant microparticles act as sites that favour the anchoring of the coagulated ink particles. Using a triple treatment in the presence of 150 mg×L-1 SA, 25 mg×L-1 PDMAC and 0.75 g×L-1 MgO removed about 95 % of the ink particles. The supernatant obtained was characterised by a low turbidity value (about 7 NTU) and a COD value about 2000 mg×L-1

    Chemical composition, antimicrobial, antioxidant and anticancer activities of essential oil from Ammodaucus leucotrichus Cosson & Durieu (Apiaceae) growing in South Algeria

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    ABSTRACT. The chemical composition of the essential oil obtained by hydrodistillation from aerial parts of A. leucotrichus Cosson & Durieu (Apiaceae) grown in the south of Algeria (El-Oued) was determined by GC-MS analysis. The oil was found to be rich in perilladehyde 64.66% and D-Limonene 26.99%. The biological activity of A. leucotrichus Cosson & Durieu essential oil has been investigated. The in vitro antimicrobial activity of the essential oil sample was tested on eight strains, one yeast and one fungi. The test showed interesting antimicrobial properties, especially on Salmonella enterica and E. coli, the antioxidant capacity of the oil was measured using the cyclic voltammetry, and the AAT value of A. leucotrichus essential oil was evaluated 47.84 mg α-TE/L. In addition, the antitumor activity showed that the oil of A. leucotrichus was very significant against the HCT116 colon cancer cell line.               KEY WORDS: Ammodaucus leucotrichus, Antioxidant activity, Anticancer activity, Cyclic voltammetry Bull. Chem. Soc. Ethiop. 2019, 33(3), 541-549. DOI: https://dx.doi.org/10.4314/bcse.v33i3.1

    RNA editing regulates insect gamma-aminobutyric acid receptor function and insecticide sensitivity

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    A-to-I pre-mRNA editing by adenosine deaminase enzymes has been reported to enhance protein diversity in the nervous system. In Drosophila, the resistance to dieldrin (RDL) gamma-aminobutyric acid (GABA) receptor subunit displays an editing site (R122) that is close to the putative GABA-binding site. We assessed the functional effects of editing at this site by expressing homomeric RDL receptors in Xenopus oocytes. After replacement of arginine 122 with a glycine, both agonist and fipronil potencies were shifted to the right in either fipronil-sensitive receptors or mutated resistant receptors (A301G/T350M). These data provide the first insight on the influence of RNA editing on GABA receptor function

    Guidance for Autistic Children in Increasing Confidence in Socializing

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    The fostering of autistic childrens self-confidence for the sake of their growth is an act of humanity that deserves recognition. This is done in order to comprehend and enhance their cognitive and psychological growth as a kind of systematic help in everyday life to build confidence in socializing at school and in the community. This studys issue is the counselors efforts in offering assistance to autistic youngsters. This research tries to describe the efforts of counselors to increase self-confidence via counseling. This investigation falls under the heading of qualitative field research. The total number of participants in this research was 227. The approach employed for data analysis was descriptive qualitative analysis. Descriptive qualitative data analysis was employed, which explains the scenario or events, the character of a specific population or place by obtaining factual information, justifying the situation, and making assessments in order to generate a clear picture. From the findings of the research, it can be inferred that a teachers direction is necessary to develop the social confidence of autistic children both within and outside the classroom (counselor). This is owing to these childrens inherent limits. The outcomes of the assistance provided by the counselor are sufficient to boost the self-esteem of the autistic youngsters they advise

    Assessment of Commonly Used Pesticides in the Ground Water of the Shallow Aquifer Systems in Jericho and Jeftlik areas/ Lower Jordan Valley, Occupied Palestinian Territories

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    One of the most important pollutants that may reach the groundwater through agricultural return flow combined with abuse and ignorance is pesticides. This study focuses on the examination of the concentration of three pesticides: Abamectin, Imidacloprid, and Ăź-Cyfluthrin, all of which have been used in large quantities in the Lower Jordan Valley (LJV) for the last three decades. Twenty five groundwater samples were collected from water boreholes where water is abstracted from two phreatic aquifer systems which are the Plio-Plistocene aquifer system in Jericho and Lower Al Jeftlik areas and the Eocene carbonate aquifer system in the Middle of Al Jeftlik. The depth of the boreholes in both aquifer system ranges between 80 and 120 m. Water samples were analyzed for Abamectin, Imidacloprid, and Ăź-Cyfluthrin using the HPLC-UV method. These samples represent two main agricultural locations (Jericho, and the Al Jeftlik). Of the 25 wells sampled, Abamectin was detected in 11 wells in concentrations ranging between 1.24 ppb and 81.71ppb. Imidacloprid was detected in 24 wells in concentrations ranging between 1.60ppb and 325.0ppb. Finally, Ăź-Cyfluthrin was detected in 7 wells in concentrations ranging between 1.10 and 24.46ppb. Aquifer lithology, groundwater flow directions, type of agricultural activity are major factors in controlling pesticide concentrations in groundwater. The highest values were measured where the aquifer consists of gravel and sand sediments, combined with intensive agricultural activities, followed by sand-silt aquifer. The lowest concentrations were found in boreholes where carbonate aquifer is the main source of water which indicates that other source of water flow into the system. The results of this study demonstrate that these pesticides are used heavily and in an improper way in the lower Jordan Valley, increasing the risk of adverse environmental and public health effects. Much attention should be given to addressing the potential problem of environmental and groundwater contamination by these pesticides.This study was funded through BARD-project /USDA

    3D Face Recognition Benchmarks on the Bosphorus Database with Focus on Facial Expressions

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    This paper presents an evaluation of several 3D face recognizers on the Bosphorus database, which was gathered for studies on expression and pose invariant face analysis. We provide identification results of three 3D face recognition algorithms, namely generic face template based ICP approach, one-to-all ICP approach, and depth image-based Principal Component Analysis (PCA) method. All of these techniques treat faces globally and are usually accepted as baseline approaches. In addition, 2D texture classifiers are also incorporated in a fusion setting. Experimental results reveal that even though global shape classifiers achieve almost perfect identification in neutral-to-neutral comparisons, they are sub-optimal under extreme expression variations. We show that it is possible to boost the identification accuracy by focusing on the rigid facial regions and by fusing complementary information coming from shape and texture modalities

    L’aspergillome sphenoïdal : a propos d’un cas sphenoidalaspergilloma : a case report

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    Introduction : L’aspergillose sphénoïdale isolée est une pathologie rare potentiellement grave vu le risque d’extension neuro-méningée et orbitaire. malgré qu’elle est plus fréquente chez les immuno-déprimés, l’atteinte de l’immunocompétent a été décrite. a travers une observation, nous rapportons les caractéristiques clinico-radiologiques, thérapeutiques et évolutives de l’aspergillome sphénoïdal.Observutin : Homme de 35 ans a consulté pour des céphalées rétro-orbitaires évoluant depuis 3 mois. L’examen était normal à part une rhinorrhée purulente postérieure. Le scanner a montré un processus hétérogène comblant le sinus sphénoïdal associé à une lyse osseuse. Une sphénoïdotomiepar voie endonasale a permis de confirmer le diagnostic et de nettoyer les lésions aspergillaires. Un traitement par voriconazol a été associé avec évolution favorable après un recul de 18 mois.Conclusion : L’aspergillome sphénoïdale est l’un des diagnostics différentiel des tumeurs sphénoïdales chez l’immunocompétent. Le traitement est essentiellement chirurgical avec de très bons résultats. L’adjonction d’un antifongique systémique est controversée chez l’immunocompétent.Mots- clefs : aspergillome, sphénoïde, imagerie, Tumeur, chirurgieObjective : Isolated sphenoidalaspergillosis is rare but potentially grave because of the risk of neuro-meningeal and orbitalextension. althoughitis more common in immuno-compromised, the achievement of immunocompetent has been described. Through an observation, we report the clinic-radiological, therapeutic and evolutionary featuresof sphenoidalaspergilloma.Case-report : male 35 years consulted for retro-orbital headache lasting for 3 months. The exam was normal except a purulent rhinorrhea. The CT scan showed a heterogeneous process filling the sphenoid sinus associated with bone loss. Sphenoidotomy by an endonasal approach confirmed the diagnosis of aspergillosis lesions. Treatment with voriconazole was associated with favorable outcome after 18 months.Conclusion : Sphenoidal as pergilloma is a differential diagnosis of tumors in the immuno-competent. Treatment is mainly surgical with good results. The addition of a systemic antifungal agent is controversial in the immunocompetent.Keywords : aspergilloma, sphenoïd, imagery, tumor, surger

    Phenomenology of a Light Cold Dark Matter Two-Singlet Model

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    We study the implications of phenomenological processes on a two-singlet extension of the Standard Model we introduced in a previous work to describe light cold dark matter. We look into the rare decays of ÎĄ\Upsilon and BB mesons, most particularly the invisible channels, and study the decay channels of the Higgs particle. Preferred regions of the parameter space are indicated, together with others that are excluded. Comments in relation to recent Higgs searches and finds at the LHC are made.Comment: 16 pages, 8 figure

    Inhibition of protein kinase C decreases sensitivity of GABA receptor subtype to fipronil insecticide in insect neurosecretory cells.

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    Phosphorylation by serine/threonine kinases has been described as a new mechanism for regulating the effects of insecticides on insect neuronal receptors and channels. Although insect GABA receptors are commercially important targets for insecticides (e.g. fipronil), their modulation by kinases is poorly understood and the influence of phosphorylation on insecticide sensitivity is unknown. Using the whole-cell patch-clamp technique, we investigated the modulatory effect of PKC and CaMKinase II on GABA receptor subtypes (GABAR1 and GABAR2) in DUM neurons isolated from the terminal abdominal ganglion (TAG) of Periplaneta americana. Chloride currents through GABAR2 were selectively abolished by PMA and PDBu (the PKC activators) and potentiated by Gö6983, an inhibitor of PKC. Furthermore, using KN-62, a specific CaMKinase II inhibitor, we demonstrated that CaMKinase II activation was also involved in the regulation of GABAR2 function. In addition, using CdCl(2) (the calcium channel blocker) and LOE-908, a blocker of TRPγ, we revealed that calcium influx through TRPγ played an important role in kinase activations. Comparative studies performed with CACA, a selective agonist of GABAR1 in DUM neurons confirmed the involvement of these kinases in the specific regulation of GABAR2. Furthermore, our study reported that GABAR1 was less sensitive than GABAR2 to fipronil. This was demonstrated by the biphasic concentration-response curve and the current-voltage relationship established with both GABA and CACA. Finally, we demonstrated that GABAR2 was 10-fold less sensitive to fipronil following inhibition of PKC, whereas inhibition of CaMKinase II did not alter the effect of fipronil

    Awareness of the Importance of and Adherence to Patients’ Rights Among Physicians and Nurses in Oman: An analytical cross-sectional study across different levels of healthcare

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    Objectives: This study aimed to determine the extent to which physicians and nurses in Oman were aware of the importance of and adhere to patients’ rights and whether this differed according to role, nationality, position and institutional healthcare level. Methods: This analytical cross-sectional study was carried out between December 2015 and March 2016 at various governmental healthcare institutions in Oman. A self-administered questionnaire was distributed to 1,385 practitioners at all healthcare levels. Results: A total of 1,213 healthcare practitioners (response rate: 87.58%) completed the survey, of which 685 (56.47%) were nurses and 528 (43.53%) were physicians. Overall, awareness of the importance of patients’ rights was high (91.51%), although adherence to these rights in practice was low (63.81%). The right of the patient to be informed was considered least important and was least adhered to (81.2% and 56.39%). Nationality, role and institutional level were significantly associated with awareness (P = 0.002, 0.024 and 0.034, respectively). Non-Omani staff were significantly more likely than Omani staff to be aware of (odds ratio [OR] = 1.696; P = 0.032) and adhere to (OR = 2.769; P <0.001) patient rights. Furthermore, tertiary care staff were twice as likely as primary care staff to perceive the importance of patient rights (OR = 2.076; P = 0.019). While physicians were more likely than nurses to be aware of the importance of patient rights, this difference was not significant (OR = 1.516; P = 0.126). Conclusion: These findings may help inform measures to enhance awareness of and adherence to patients’ rights in Oman.Keywords: Medical Ethics; Patient Rights; Awareness; Adherence; Physicians; Nurses; Oman
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