369 research outputs found

    Novel micro-flat springs using the superior elastic properties of metallic glass foils

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    A thin metallic glass foil of 100 mg mass forming a sinusoidal arc behaves as non-conventional flat micro-spring withstanding loads 105 times higher than its load. Upon a normal load applied on the top of the arc, the foil deforms elastically leading to sinusoidal wavy patterns of higher order. The lifespan of the novel spring is higher than conventional low cycle springs and can potentially be further improved by eliminating surface and edge preparation induced defects. This unique behavior of metallic glass foils has the potential to revolutionize the field of springs and can be exploited for numerous applications

    USE OF CHROMAGAR ORIENTATION FOR PRESEMPTIVE IDENTIFICATION OF ENTEROCOCCI AND CHARACTERIZATION OF ANTIMICROBIAL RESISTANCE OF THE ISOLATES

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    This study was conducted to evaluate the use of CHROMagar Orientation for presumptive identification of enterococci from poultry, and to characterize the antimicrobial resistance of the isolates. Strains identification with conventional methods allowed confirmation of Enterococcus genus membership of all of the isolates on CHROMagar orientation (100%). Of the 141 enterococci isolates obtained from chicken, 81 (57.45%) were identiïŹed as Enterococcus faecalis and 60 (42.55%) as Enterococcus faecium. The antimicrobial susceptibility test presented high level of resistance to Tetracycline (89%) and Erythromycin (65%), low level of resistance to High Level of Streptomycin, Penicillin and Ciprofloxacin (13%, 10% and 9% respectively). Few of isolates were resistant to Chloramphenicol (2%). All the strains were susceptible to High Level of Gentamycin, Ampicillin, Vancomycin and Nitrofurantoin. The predominant phenotype of resistance pattern identified in both E.faecalis and E.faecium was (Erythromycin -Tetracycline)

    La différence épidémiologique des hémorragies digestives hautes entre les hommes et les femmes

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    Introduction: Des diffĂ©rences Ă©pidĂ©miologiques, Ă©tiologique voire pronostique des hĂ©morragies digestives hautes (HDH) entre les deux sexes opposĂ©s ont Ă©tĂ© citĂ© par diffĂ©rentes Ă©tudes. MĂ©thodes: Nous avons essayĂ© de dĂ©celer ces diffĂ©rences Ă  travers une analyse rĂ©trospective nichĂ©e sur une Ă©tude prospective sur les hĂ©morragies digestives hautes ayant inclus 945 patients.RĂ©sultats: Six cents trente-sept patients Ă©taient des hommes (67,4% Vs 32,6%). Un antĂ©cĂ©dent d’HDH Ă©tait trouvĂ© chez 24,2% des cas sans diffĂ©rence significative entre les deux sexes. L’ñge de survenue de l’hĂ©morragie Ă©tait plus Ă©levĂ© chez les femmes que chez les hommes : 51,5 ans ± 18,8 Vs 47,8 ans ± 18,3 (p : 0,003). Les Ă©tiologies de l’HDH Ă©taient diffĂ©rentes entre les deux sexes. Alors que l’hĂ©morragie liĂ©e Ă  l’HTP Ă©tait la premiĂšre cause chez la femme (38 % Vs 23,5 % chezl’homme, p<0,0001), c’est la pathologie ulcĂ©reuse qui venait en premier chez l’homme (62 % Vs 36,7 % chez la femme, p <0,0001). Un besointransfusionnel Ă©tait notĂ© chez 42,4 % des patients de sexe masculin contre 35,4 % des patientes avec un p = 0,03. Le taux de rĂ©cidive et de dĂ©cĂšs global Ă©taient de 7,5 % et de 5,7 % des cas respectivement, sans diffĂ©rence significative entre les deux sexes.Conclusion: L’étude trouve un profil Ă©pidĂ©miologique, clinique et Ă©tiologique diffĂ©rent selon le sexe des patients.Key words: HĂ©morragie digestive haute, Ă©pidĂ©miologie, sexe masculin, sexe fĂ©minin, endoscopie, ulcĂšre gastroduodĂ©nal, hypertension portal

    Activités antifongiques in vitro des huiles essentielles de Mentha pulegium, Eugenia aromatica et Cedrus atlantica sur Fusarium culmorum et Bipolaris sorokiniana.

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    L’activitĂ© antifongique des huiles essentielles (HE) extraites de trois plantes aromatiques et mĂ©dicinales: Mentha pulegium L., Eugenia aromatica L. et Cedrus atlantica (Manetti ex Endl.).a Ă©tĂ© testĂ©e in vitro sur deux champignons pathogĂšnes des cĂ©rĂ©ales : Fusarium culmorum ((Wm.G.Sm.) Sacc. 1892) et Bipolaris sorokiniana ((Sacc.) Shoemaker, 1959). Les milieux de culture utilisĂ©s pour ces deux pathogĂšnes sont respectivement : le milieu PDA et le milieu V8. Partant des concentrations mĂšres de 1,25 ml d’huile essentielle par litre du milieu de culture, pour chaque champignon, les concentrations minimales inhibitrices (CMI) de ces huiles essentielles ont Ă©tĂ© dĂ©terminĂ©es par dilutions successives des solutions mĂšres, et les effets fongicide et/ou fongistatique de ces dilutions ont Ă©tĂ© mis en Ă©vidence. Ainsi pour Fusarium culmorum, l’HE d’Eugenia aromatica s’est avĂ©rĂ©e la meilleure avec la concentration minimale fongicide de 0,624 ml/L, vient ensuite celle de Mentha pulegium dont la concentration mĂšre est de 1,25 ml/L a Ă©tĂ© minimale fongicide, mais cette mĂȘme concentration de Cedrus atlantica a seulement ralenti le dĂ©veloppement de ce champignon. Pour Bipolaris sorokiniana, la concentration de 0,156 ml/L de HE d’Eugenia aromatica est la CMI, et elle est fongistatique. Les concentrations utilisĂ©es pour les HE de Mentha pulegium et Cedrus atlantica ont toutes ralenti le dĂ©veloppement du champignon sans pour autant l’arrĂȘter complĂštement

    Investigation on the mechanically-induced nanocrystallization in metallic glasses

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    Shear-induced nanocrystallization in bent ribbons of Pd40Cu30Ni10P20 metallic glass has been quantitatively investigated via synchrotron radiation. The formed nanocrystals volume fraction during deformation has been directly estimated from X-ray diffraction spectra using peaks area integration. The nanocrystallization process during deformation was found to be strongly linked with the microstructure configuration of shear bands in amorphous alloys. A constitutive model based on free volume approach has been introduced to describe the kinetic of mechanically induced nanocrystallization. The solution of the coupled constitutive equations of the model, fitted to experimental data, permits to determine the physical and mechanical parameters governing the phenomena of shear-induced crystallization in metallic glasses

    Mechanically induced waves in metallic glass foils

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    The response of vitrified metallic arc foils under normal load is studied. Application of normal load on an initial arc shaped vitrified metallic foil is followed by multiplication of the initial arc. A sinusoidal mathematical expression can be used for the description of the produced harmonic undulations. The number of the formed waves increases as the displacement increases. Therefore, this undulatory behavior of the vitrified foils can be exploited as a flat spring with multiple spring constants. For comparison crystalline foils were tested. The enormous elastic region of vitrified alloys allows this undulatory response to occur extensively while plastic deformation is unavoidable when crystalline foils are used. Exploiting the metallic glass characteristics, the predefined extrem a positions of the formed undulations and the mechanical characteristics of the vitrified foils a new type of electromechanical switch is suggested. (c) 2015 Elsevier Ltd. All right

    Relationship between postharvest diseases resistance and mineral composition of citrus fruit

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    reen and blue moulds, due to the pathogenic action of Penicillium digitatum and Penicillium italicum respectively are the main cause of orange losses during postharvest. Under Mediterranean climate conditions, both together are responsible for 80% of total postharvest citrus fruit decay. The type of orchard production system, field location with different types of climate and soil has a main influence on mineral composition of fruits. The mineral composition of fruits can have a significant impact on fruit quality and shelf life during postharvest period. These include effects on fruit colour, texture, disease susceptibility, juice composition and development of physiological disorders. Oranges from different regions from South of Spain and Portugal and from three different production systems (conventional, integrated and organic) were studied to evaluate whether both factors (origin and production system) affected the degree of fruit sensitivity to decay. Results indicate that the sensitivity to green or blue mould is determined better by the origin of fruit than by the system of production.info:eu-repo/semantics/publishedVersio
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