734 research outputs found
Diversity analysis of Moroccan carob ("Ceratonia siliqua" L.) accessions using phenotypic traits and RAPD markers
Diversity analysis of moroccan carob (Ceratonia siliqua L.) accessions using phenotypic traits and RAPD markers. The carob (Ceratonia siliqua L.) is a perennial leguminous (Caesalpinioideae) that grows as an evergreen shrub or tree. It¿s an important component of the Mediterranean vegetation and its adaptation in marginal soils of the Mediterranean regions is important environmentally and economically. Phenotypic and genetic diversity among 10 Ceratonia siliqua accessions coming from different areas of Morocco were studied with morphometric and RAPD approaches. The analysis of discriminative fruit characters showed highly significant differences among these accessions, the closely related ones have a similarity level less than 65%. No molecular studies have been carried out so far on Ceratonia siliqua. To provide markers useful for molecular diversity study of the carob tree, genomic DNA extraction and amplification conditions were finalized and 67 arbitrary primers were screened. 52 of them showed clearly reproducible banding patterns. The analysis of RAPD profiles revealed a high degree of genetic diversity within these carob accessions and enabled each of them to be uniquely fingerprinted. Overall, in our study we note that morphological relationship between carob accessions is deeply different to their molecular relationship. Concerning the distribution of the accessions according to their geographical origin, clustering based on RAPD data revealed a rough distribution of theses accessions. Indeed, Sidi Bou Ottman, Demnate and Essaouira accessions coming from the south of Morocco seem to be linked in the PCA plot. However, two geographically distant accessions, Aïn Sfa and Ouazzane coming from the north (about 700 Km) were clustered with Essaouira and Demanate - Sidi Bou Ottman, respectively.Analyse de la diversité des accessions du caroubier marocain (Ceratonia siliqua L.) utilisant des traits phenotypiques et des marqueurs RAPD. Le caroubier (Ceratonia siliqua L.) est une légumineuse pérenne (Caesalpinioideae), à feuillage persistant et pouvant croître entant qu¿arbrisseau ou arbre. C¿est un composant important de la végétation méditerranéenne et son adaptation aux sols marginaux des régions méditerranéennes est d¿une grande importance écologique et économique. La diversité phénotypique et génétique au sein de 10 accessions de caroubier provenant de différentes régions du Maroc a été étudiée par des approches morphométriques et moléculaires (RAPD). L¿analyse des caractères morphologiques discriminants du fruit a montré des différences hautement significatives au sein des accessions, puisque les apparentées d¿entre elles n¿ont approximativement que 65% de similarité. Jusqu¿à nos jours, aucune étude moléculaire n¿a été entreprise sur Ceratonia siliqua. Pour mettre à disposition des marqueurs utiles pour l¿étude de la diversité moléculaire du caroubier, l¿extraction de l¿ADN génomique et les conditions de l¿amplification ont été mises au point et 67 amorces arbitraires ont été criblées. 52 d¿entre elles ont montré clairement des profils de bandes reproductibles. L¿analyse des profils RAPD a révélé une diversité génétique de haut niveau entre les accessions de caroubier ce qui a permis à chacune d¿elles d¿être distinguée génétiquement de façon singulière. De manière générale, nous avons noté que la relation morphologique entre les accessions du caroubier est profondément différente de leur relation moléculaire. Concernant la distribution des accessions selon leur origine géographique, le regroupement basé sur les données de la RAPD a révélé une distribution grossière. En effet, les provenances de Sidi Bou Ottman, Demnate et Essaouira, originaires du sud de Maroc, semblent être liés par l¿analyse des composantes principales (PCA). Cependant, deux accessions géographiquement distantes, Aïn Sfa et Ouazzane, originaires du Nord (approximativement 700 Kms) ont été liées avec Essaouira et Demanate - Sidi Bou Ottman, respectivement
Design systems at work: Optimizing design processes and aligning design work to company identity
User experience design in a company setting typically involves teams comprised of individuals with diverse roles, who need to collaborate when creating products and services. Resources exist to set standards for design within such a company, guiding teams of designers and developers to create products and services with a consistent look and feel that are also in line with the company’s branding. These resources include UX guidelines, UI style guides, design patterns, and design languages. The latest such resource is the design system.
This thesis explores the term design system in terms of its definition and how it is applied by design professionals within companies. It seeks to understand how to define the term and how to create a design system to support the needs of a company’s design teams, and ultimately, provide a pleasant and consistent experience for end users. Following this focus on design in practice, the literature review has a heavy emphasis on articles and blog entries by working designers explaining what design systems are to them, how they have built them, and how they use them. This is complemented by academic literature on topics related to collaborative work in digital product teams, design management, and storytelling methods to drive adoption within companies. Expert interviews were also conducted with design professionals who have led design system teams in organizations. The literature review and expert interviews revealed a definition for design system that is not standardized, yet fairly consistent from speaker to speaker. Design systems broadly encompass the early types of standardizations for design. They include design languages, guidelines, and style guides. They go even further by not only establishing standards for how designs should look and lead to interactions. Design systems also provide the philosophy behind the design decisions that were made, relating them to the company’s mission and branding.
This thesis also contains a case study with the global engineering company ABB, tracing the beginning of its central design team and transition from a UI style guide to a design system. Designers and developers throughout the company were surveyed and interviewed to hear their needs and expectations. Service design approaches were used to conduct participatory research with stakeholders within the company, with the aim of engaging them in the process of creating a design system.
Implications on a company level, industry level, and academic level are discussed. This thesis on design systems supports the case company ABB in creating its design system, and on a broader scale, connects academic and industry discussions on collaborative work in design teams to explain how design systems can be built and used
Les hôtes réservoirs du virus de la striure du maïs (MSV) en zone soudano-sahélienne : identification et distribution spatio-temporelle
Une vaste prospection dans la flore herbacée du Burkina Faso à différentes périodes de l'année et pendant 3 ans a permis de collecter 41 espèces de Poaceae portant les symptômes de la striure du maïs. En utilisant le test immuno-enzymatique ELISA, il a été possible de détecter le virus de la striure du maïs (MSV) dans 35 échantillons. Le virus a pu être également transmis au maïs (Zea mays) par la cicadelle, Cicadulina triangula [Homoptera: Ciccadellidae] à partir de 32 de ces hôtes. Vingt quatre des hôtes du MSV ainsi identifiés n'avaient jamais été encore rapportés comme tel. L'étude de la répartition spatio-temporelle des réservoirs a permis d'obtenir trois résultats importants: a) c'est dans la zone de maïsiculture que les réservoirs sont les plus abondants; b) l'incidence de la maladie dans les champs de maïs est proportionnelle à l'abondance des réservoirs; c) c'est seulement 3 à 4 semaines après le début de la saison des pluies que la quantité de réservoirs devient importante. Il est conclu que des semis précoces devraient permettre de minimiser l'effet de la maladie sur les rendements du maïs.An intensive survey of herbaceous plants of Burkina Faso was carried out at different periods of the year during 3 yr. This permitted the collection of 41 Poaceae species showing maize streak symptoms. Using the ELISA method, maize streak virus (MSV) was detected in 35 samples. Transmission of the virus to corn (Zea mays) with the use of the leaf hopper Cicadulina triangula [Horroptera: Ciccadellidae], was possible for 32 of the 35 host samples tested.Twenty-four of these reservoirs have not been reported elsewhere as hosts of MSV. A study of the spatio-temporal distribution of reservoirs led us to three important conclusions: a) corn production areas are the most vulnerable zones for reservoir abundance; b) disease incidence on corn in the field is proportional to reservoir abundance; c) reservoirs increase rapidly within 3 or 4 week of rainfall after the beginning of the rain season. It is suggested that maize should be sown early in order to reduce incidence of MSV in Burkina Faso
Variabilité du virus de la striure du maïs (MSV) en zone soudano-sahélienne
Une étude de la variabilité du virus de la striure du maïs (MSV) a été réalisée au Burkina Faso, situé dans la zone soudano-sahélienne. De 1990 à 1992, 1240 échantillons ont été prélevés sur 36 hôtes naturellement infectés par le virus. Ils ont été analysés à l'aide du test ELISA, en utilisant cinq anticorps monoclonaux préparés contre le virus et par transmission du virus à quelques hôtes naturels. Trois variants sérologiques du virus, désignés par SK, VD114 et VD180, ont été caractérisés. D'autre part, il s'est avéré qu'il existait deux formes symptomatiques du variant SK soit SKF induisant des symptômes prononcés et SKf, des symptômes faibles. Chez le maïs (Zea mays), en infection mixte, le variant SK masquait les deux autres variants du MSV. L'apparente uniformité antigénique des isolats MSV du maïs observée par plusieurs auteurs a été attribuée à ce phénomène de masquage.A study of the variability of the maize streak virus (MSV) was conducted in Burkina Faso, which is part of the Sudano-Sahelian region. From 1990 to 1992, 1240 samples were collected on 36 hosts naturally infected by the virus. These samples were analysed with ELISA, using five monoclonal antibodies developed against the MSV and by transmission of the virus to some natural hosts. Three serological variants of the virus, designated as SK, VD114, and VD180 were characterized. The SK variant was further divided into two forms, namely SKF and SKf, which induced severe and mild symptoms, respectively. In maize (Zea mays), with multiple infection, the SK variant masked the other two MSV variants. The apparent antigenic uniformity of the MSV isolates from maize observed by many authors has been linked with this masking effect
Multivalued anisotropic problem with Fourier boundary condition involving diffuse Radon measure data and variable exponents
We study a nonlinear anisotropic elliptic problem under Fourier type boundary condition governed by a general anisotropic operator with variable exponents and diffuse Radon measure data which does not charge the sets of zero p(·)-capacity. We prove an existence and uniqueness result of entropy or renormalized solution
Identification Et Cartographie Des Zones Potentielles De Recharge Des Eaux Dans La Région De Dosso (Sud-Ouest, Niger) Par Analyse Multicritère
Les eaux souterraines constituent la principale sourced’approvisionnement en eau des populations de la région de Dosso, située dansle Sud-Ouest du bassin des Iullemmeden. En dépit du climat aride à semi-aridequi caractérise cette région, le renouvellement des eaux des nappessouterraines s’effectue à travers les pluies. Cette recharge des eaux, quiconstitue un élément essentiel dans le cycle hydrologique, se faitpréférentiellement selon des zones qui peuvent aussi être des zonesvulnérables à la pollution des nappes. L’objectif principal de cette étudeconsiste à identifier puis à cartographier les zones potentielles de recharge deseaux. La démarche méthodologique utilisée dans le cadre de ce travail anécessité l’utilisation de l’analyse multicritère combinant le Systèmed’Information Géographique (SIG) et la télédétection. Après le traitement desimages Landsat de Dosso, tous les paramètres influençant les processus derecharge des eaux ont été intégrés au SIG. Il s’agit : des types de sol, del’occupation du sol, des densités des fractures et du drainage, de la lithologiede la zone non saturée et de la pente du terrain. La carte des zones potentiellesde recharge des eaux montre que la majorité de la zone étudiée présente unpotentiel réel d’infiltration des eaux lié à : la nature sableuse des sols, laprésence des zones de cultures pluviales, la présence de fractures et la densitédu réseau hydrographique. Cette carte a aussi permis de confirmer que leszones à potentiel élevé de recharge se situent dans les lits des mares et des"dallols" (larges vallées sèches), qui deviennent ainsi des zones plusvulnérables. Ce support cartographique constitue de ce fait un outil d’aide à ladécision.
Groundwater is the main source of water supply in the Dosso regionwhich is located in the southwestern part of the Iullemmeden Basin. Despitethe arid to semi-arid climate that characterizes this region, groundwaterrecharge is occuring mainly through rainfall. This recharge of water which isan essential element in the hydrological cycle is prefentially done accordingto zones which can also be vulnerable to groundwater pollution. The mainobjective of this study is to identify and mapped the potential recharge areas.A methodology based on a multicriteria analysis integrating GIS and remotesensing was used to map the potential recharge areas. After processing theLandsat satellite images of Dosso region, all the parameters influencing thehydrological recharge processes were obtained and integrated into GIS. Theseparameters are: soil types, land cover, fracture density, drainage density,lithology and slope. The map of potential recharge areas obtained shows thatthe majority of the study areas has great recharge potential. According to thisstudy, this great potentiality could be linked to: the sandy nature of the soil,the cultivable areas, the presence of fractures and density of hydrographicnetwork. This map also confirmed that areas with high recharge potential arelocated in the beds of ponds and "dallols" (wide dry valleys), which thusbecome more vulnerable areas. This map of potential recharge areasconstitutes therefore a tool for decision makers
QUANTIZATION NOISE ESTIMATION FOR LOG-PCM
ITU-T G.711.1 is a multirate wideband extension for the wellknown ITU-T G.711 pulse code modulation of voice frequencies. The extended system is fully interoperable with the legacy narrowband one. In the case where the legacy G.711 is used to code a speech signal and G.711.1 is used to decode it, quantization noise may be audible. For this situation, the standard proposes an optional postfilter. The application of postfiltering requires an estimation of the quatization noise. In this paper we review the process of estimating this coding noise and we propose a better noise estimator. Index Terms — Postfilter, quantization noise 1
Africa and the francophonie of tomorrow: An attempt to measure the population of the Francophonie from now to 2060
Habib Bourgiba, Hamani Diori and Léopold Sédar Senghor are considered the fathers of the Organisation Internationale de la Francophonie (OIF), an international community created in the early 1960s that currently unites more than thirty countries where the French language is given a major role in public life, education, the arts, law, the media, etc. Some present the OIF as a neo-colonial organization, while others think of it as protecting the world’s cultural diversity in the face of globalization. Regardless, this assembly of countries around the world has played and should continue to play a significant role in international politics. However, the configurational changes this Francophone community has experienced since its inception in the 1960s are nothing compared with those we predict for the next 50 years. In fact, the most recent demographic trends outlined in the United Nations’ latest population projections are leading to a major reconfiguration of the demographic weight of the countries of the world, particularly in Africa. In this context, we were interested to try a forward-looking exercise based on these most recent projections from the UN that could allow us to define the Francophonie of tomorrow by exploring the evolution of Africa’s demographic weight. In the coming decades, what will be the size and the geographic distribution of the Francophone population? How has Africa’s demographic weight in the espace francophone evolved? And how will it evolve in the future? In this article, we try to better define the demographic outline of tomorrow’s Francophonie by drawing on different definitions of the espace francophone, while highlighting some of the political and social issues of this forward-looking exercise for the Francophone community in general, and for Africa in particular
Dissipative Soliton Resonance Curve under Influence of Nonlinear Gain
International audienceWe investigate the effect of the cubic nonlinear gain on the resonance curve in the frame of the dissipative soliton resonance (DSR) in a complex cubic-quintic Ginzburg-Landaumodel. The DSR occurs when the energy of a soliton in the system increases without limit at certain values of the system parameters. We remind analytical expression for the resonance curve, thanks to the collective variable approach. We show that the nonlinear gain has a linear response for the spectral filtering and the saturation of the Kerr nonlinearity, however, has a nonlinear response for the linear loss and the saturation of the nonlinear gain. Thus the gain and its saturation in the system can be suitably chosen for generation of high-energy pulses. These results can be helpful to design laser systems or to optimize the active parameters of cavities that generate solitons with the highest possible energy
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