62 research outputs found

    CHEMICAL COMPOSITION OF THE ESSENTIAL OIL OF CLADANTHUS SCARIOSUS(ASTERACEAE) WILD GROWN IN MOROCCO

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    Cladanthus Cass. [Syn. Ormenis (Cass.) Cass.] is a genus of the family Asteraceae, endemic to the Mediterranean region and related to the tribe Anthemideae (1). It comprises 15 species including C. scariosus (Ball) Oberpr. & Vogt [Bas. Santolina scariosa; Syn. Ormenis scariosa Litard. & Maire] from Morocco where is concentrates 1/3 of the species of the genus (2). Some of these are perennial, suffruticose and strongly aromatic plants. C. mixta (L.) Chev. is used in Morocco as chamomile and this is commonly called Moroccan chamomile. In the same country, C scariosus is fairly common in open places, on sandstone substrates (3) and is characterized by a strong aromatic character, this has motivated the authors – some of which were previously occupied by other species of the same genus (4) – to undertake such study phytochemical. In this study, the authors present the results of chemical composition of the essential oil of Cladanthus scariosus wild grown in many regions of Morocco (5). Hydrodistillation of C. scariosus aerial parts, collected on the thermo-mediterranean belt of the central High Atlas – Oukeimeden, from Marrakech to Quarzazate – during the flowering phase gave a pale yellow oil. Overall, sixty-four compounds were identified, representing 92.7% of the total components. The main class of the oil was represented by sesquiterpene hydrocarbons (39.8%) with germacrene D (20.7%) as the most abundant component of the class and of the oil. Monoterpene hydrocarbons, oxygenated monoterpenes and oxygenated sesquiterpenes were present in similar amount (14.8%-15.1%). In these classes the main products were α-pinene (4.8%) and sabinene (6.9%) among the monoterpene hydrocarbons, (E)-chrysanthenyl acetate (8.3%) among the oxygenated monoterpenes and τ –muurolol (4.2%) and (E,E)-farnesyl acetate (3.9%) among the oxygenated sesquiterpenes. It is also noteworthy the good presence of chamazulene (7.1%)

    Chorological and conservation status of the endemic cypress, Cupressus atlantica Gaussen, in the High Atlas (Morocco)

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    18 p. ; tablas, mapas, gráf.We present a study of the distribution, ecology and conservation status of Cupressus atlantica, an endemic tree of the High Atlas (Morocco). The main populations of this species grow in a reduced area along the N’Fiss valley in the Central High Atlas and are gradually receding. Particular populations are increasingly fragmented and the total area covered by the cypress woodland has decreased to less than a third of the surface occupied in the 1930s. Overgrazing reduces the woodlands’ regenerative capacity, and the exploitation of the wood, linked to traditional uses by the rural society of the N’Fiss valley, directly reduces the number of trees. Great efforts being made to protect the species by the Haut Commissariat aux Eaux et Forêts are having some effect in recent years.This research was partially funded by the cooperation between the Spanish Research Council (CSIC) and the Polish Academy of Sciences (PAS).Peer reviewe

    Analyse de la Biodiversité floristique des zones humides du maroc. Flore rare menacée et halophile

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    Analysis of the moroccan wetlands floristical diversity: rare, threatened and halophilous flora. The moroccan wetlands flora shows a great floristical richness of these ecosystems, estimated at more than 670 species and subspecies (83 families) which can be supplemented by at least 272 others taxa considered rather as terrestrials but can colonize periodically these biotopes. This flora shows a rate of endemism close to 6,5 %, but the most fact is the great proportion of rare or threatened taxa (estimated at 34%). The halophilous flora was a subjet of particular comment considering the prevalence of the salt biotopes in Morocco, either by the number or the extent of the sites. It counts 115 species and subspecies distributed among 20 families

    Maladie de Castleman: Localisation inhabituelle du thorax

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    La maladie de Castleman est une affection rare qui peut toucher le thorax. La localisation diaphragmatique est exceptionnelle. Nous rapportons le cas d’une patiente de 47 ans, chez qui une thoracotomie exploratrice a permis l’exérèse d’une masse du sinus médiastinal antérieur droit, en continuité avec le diaphragme et dont l’histologie est en faveur de la maladie de Castleman de type hyalino-vasculaire. Les particularités cliniques,radiologiques et évolutives ont été revues.Key words: Maladie de Castleman, localisation, thorax, exérèse, chirurgi

    Physical mechanisms and scaling laws of K-shell double photoionization

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    We report on the photon energy dependence of the K-shell double photoionization (DPI) of Mg, Al, and Si. The DPI cross sections were derived from high-resolution measurements of x-ray spectra following the radiative decay of the K-shell double vacancy states. Our data evince the relative importance of the final-state electron-electron interaction to the DPI. By comparing the double-to-single K-shell photoionization cross-section ratios for neutral atoms with convergent close-coupling calculations for He-like ions, the effect of outer shell electrons on the K-shell DPI process is assessed. Universal scaling of the DPI cross sections with the effective nuclear charge for neutral atoms is revealed

    Double K-shell photoionization of low-Z atoms and He-like ions

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    We report on the investigation of the photon energy dependence of double 1s photoionization of light atoms and compare the cross sections for hollow atom and He-like ion production. Measurements of the Kα hypersatellite x-ray spectra of Mg, Al, and Si were carried out using the Fribourg high-resolution x-ray spectrometer installed at the ID21 and ID26 beam lines at the ESRF. The double-to-single photoionization cross section ratios were derived as a function of the incident photon beam energy and compared to convergent close-coupling (CCC) calculations for He-like ions. The dynamical electron-electron scattering contribution to the DPI cross-sections was found to be more important for neutral atoms than for the He isoelectronic serie

    Disentangling environmental correlates of vascular plant biodiversity in a Mediterranean hotspot

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    We determined the environmental correlates of vascular plant biodiversity in the Baetic-Rifan region, a plant biodiversity hotspot in the western Mediterranean. A catalog of the whole flora of Andalusia and northern Morocco, the region that includes most of the Baetic-Rifan complex, was compiled using recent comprehensive floristic catalogs. Hierarchical cluster analysis (HCA) and detrended correspondence analysis (DCA) of the different ecoregions of Andalusia and northern Morocco were conducted to determine their floristic affinities. Diversity patterns were studied further by focusing on regional endemic taxa. Endemic and nonendemic alpha diversities were regressed to several environmental variables. Finally, semi-partial regressions on distance matrices were conducted to extract the respective contributions of climatic, altitudinal, lithological, and geographical distance matrices to beta diversity in endemic and nonendemic taxa. We found that West Rifan plant assemblages had more similarities with Andalusian ecoregions than with other nearby northern Morocco ecoregions. The endemic alpha diversity was explained relatively well by the environmental variables related to summer drought and extreme temperature values. Of all the variables, geographical distance contributed by far the most to spatial turnover in species diversity in the Baetic-Rifan hotspot. In the Baetic range, elevation was the most significant driver of nonendemic species beta diversity, while lithology and elevation were the main drivers of endemic beta diversity. Despite the fact that Andalusia and northern Morocco are presently separated by the Atlantic Ocean and the Mediterranean Sea, the Baetic and Rifan mountain ranges have many floristic similarities – especially in their western ranges – due to past migration of species across the Strait of Gibraltar. Climatic variables could be shaping the spatial distribution of endemic species richness throughout the Baetic-Rifan hotspot. Determinants of spatial turnover in biodiversity in the Baetic-Rifan hotspot vary in importance between endemic and nonendemic species

    Assessment of the Food Habits of the Moroccan Dorcas Gazelle in M’Sabih Talaa, West Central Morocco, Using the trnL Approach

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    Food habits of the Moroccan dorcas gazelle, Gazella dorcas massaesyla, previously investigated in the 1980s using microhistological fecal analysis, in the M’Sabih Talaa Reserve, west central Morocco, were re-evaluated over three seasons (spring, summer and autumn 2009) using the trnL approach to determine the diet composition and its seasonal variation from fecal samples. Taxonomic identification was carried out using the identification originating from the database built from EMBL and the list of plant species within the reserve. The total taxonomic richness in the reserve was 130 instead of 171 species in the 1980s. The diet composition revealed to be much more diversified (71 plant taxa belonging to 57 genus and 29 families) than it was 22 years ago (29 identified taxa). Thirty-four taxa were newly identified in the diet while 13 reported in 1986–87 were not found. Moroccan dorcas gazelle showed a high preference to Acacia gummifera, Anagallis arvensis, Glebionis coronaria, Cladanthus arabicus, Diplotaxis tenuisiliqua, Erodium salzmannii, Limonium thouini, Lotus arenarius and Zizyphus lotus. Seasonal variations occurred in both number (40–41 taxa in spring-summer and 49 taxa in autumn vs. respectively 23–22 and 26 in 1986–1987) and taxonomic type of eaten plant taxa. This dietary diversification could be attributed either to the difference in methods of analysis, trnL approach having a higher taxonomic resolution, or a potential change in nutritional quality of plants over time
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