Climatic and hydrologic changes in Morroccan middle atlas during the holocene

Ponencia presentada en: IX Congreso de la Asociación Española de Climatología celebrado en Almería entre el 28 y el 30 de octubre de 2014.The Middle Atlas represents an ideal location for testing hypotheses about the Holocene environmental responses to climate change. The Holocene also represents the period in which humans have become a dominant influence on the Earth System. Two cores (marginal and central) have been sampled in Tigalmamine lake and dated by 14C. Diatoms from this cores show new data for some species of Cyclotella genera and give valuable information concerning the hydroclimatic changes in middle Atlas

El existencialismo en la obra narrativa de Virgilio Piñera

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Filosofía y Letras, Departamento de Filología Española. Fecha de lectura: 12-04-201

Å beholde på frivillige: En kvalitativ studie om motivasjon i frivillige organisasjoner

Denne bacheloroppgaven handler om motivasjon i den frivillige sektoren. Vi har definert motivasjon som en prosess som setter i gang, gir retning til, opprettholder og bestemmer intensitet i atferd. Motivasjon er drivkraften som får oss til å handle. Forskning forteller oss at motivasjon er sentralt når det kommer til frivillighet, og undersøkelser viser at det er en stor andel frivillige som slutter allerede innen det første året. Formålet med denne studien har derfor vært å undersøke hva som motiverer frivillige og søke å forstå hvordan dette henger sammen med deres vilje til å bli værende i organisasjonen. Vårt ønske er å kunne bidra med kunnskap til organisasjonene slik at de bedre kan bevare og beholde sine frivillige over lengre tid. Problemstillingen vår er derfor: ”Hva må ligge til grunn for at frivillige er motiverte, og blir i jobb over lengre tid?” Problemstillingen har blitt besvart med et komparativt casedesign. Studien ser på fire ulike frivillige organisasjoner som skiller seg i størrelse og hensikt. Det ble gjennomført tre dybdeintervjuer med en leder og to frivillige i hver organisasjon. Hensikten med intervjuene var å forstå hva som motiverer den enkelte, og høre hvilken rolle det spiller for deres vilje til å bli værende i organisasjonen. Vi utviklet forskningsspørsmål for å besvare problemstillingen, der vi så på psykologisk kontrakt, behov i ulike livsfaser og ledelsesatferd. Vi hadde også en åpenhet i forhold til å la informantene selv fortelle om andre forhold ved deres motivasjon. Etter at vi hadde foretatt datainnsamling og analyse av datamateriale fant vi at det er forskjeller mellom organisasjonene ut fra hvilket type arbeid de driver med. Videre fant vi at viljen til å fortsette med frivillig arbeidet ikke nødvendigvis avhenger av motivasjon, men at motivasjon må sees i sammenheng med hvilken livsfase de befinner seg i. Faktorer som er viktig for motivasjon, fant vi at var blant annet at det er samsvar mellom kompetanse og arbeidsoppgaver og at forventninger mellom medarbeider og leder samsvarer. Disse faktorene varierer ut fra livsfase og hvilken type arbeid en driver med

Antimicrobial activity and molecular docking studies of some imidazo[2,1-b]thiazole derivatives

The synthesis of bioactive molecules is of major importance in the pharmaceutical industry. In this context, the study was conducted to determine the antimicrobial and antifungal potential of four chalcone-based imidazo[2,1-b]thiazole derivatives already synthesized by our research group. The synthetized compounds obtained in good yield were evaluated for their antibacterial and antifungal activities against E. coli, Staphylococcus aureus, Pseudomonas aeruginosa and Fusarium, the results obtained are compared with the standard. Molecular docking studies were utilized to forecast the potential of these molecules as antimicrobial agents, the results obtained in vitro antibacterial were well confirmed by this method

Asymmetric response of forest and grassy biomes to climate variability across the African Humid Period : influenced by anthropogenic disturbance?

A comprehensive understanding of the relationship between land cover, climate change and disturbance dynamics is needed to inform scenarios of vegetation change on the African continent. Although significant advances have been made, large uncertainties exist in projections of future biodiversity and ecosystem change for the world's largest tropical landmass. To better illustrate the effects of climate–disturbance–ecosystem interactions on continental‐scale vegetation change, we apply a novel statistical multivariate envelope approach to subfossil pollen data and climate model outputs (TraCE‐21ka). We target paleoenvironmental records across continental Africa, from the African Humid Period (AHP: ca 14 700–5500 yr BP) – an interval of spatially and temporally variable hydroclimatic conditions – until recent times, to improve our understanding of overarching vegetation trends and to compare changes between forest and grassy biomes (savanna and grassland). Our results suggest that although climate variability was the dominant driver of change, forest and grassy biomes responded asymmetrically: 1) the climatic envelope of grassy biomes expanded, or persisted in increasingly diverse climatic conditions, during the second half of the AHP whilst that of forest did not; 2) forest retreat occurred much more slowly during the mid to late Holocene compared to the early AHP forest expansion; and 3) as forest and grassy biomes diverged during the second half of the AHP, their ecological relationship (envelope overlap) fundamentally changed. Based on these asymmetries and associated changes in human land use, we propose and discuss three hypotheses about the influence of anthropogenic disturbance on continental‐scale vegetation change

Contribution a la reconstitution de la paleohydrologie et de la paleoclimatologie du Maghreb et du Sahara au Quaternaire superieur a partir des diatomees

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

CHARACTERIZATION OF NEOGENE MARLS FROM THE KERT BASIN (N.E. MOROCCO): SUITABILITY FOR THE CERAMIC INDUSTRY

The North-Eastern region of Morocco is filled with marine marls of Neogene age. The Neogene marls from the lower-Kert area were characterized to evaluate their suitability in the ceramic industry. To meet this objective, two cross-sections involving all the Neogene facies were performed on the both banks of the Kert River. Grey and green marls occurring between sandstone and tuffs were characterized by mineralogical (XRD) and physico-chemical analyses (grain-size, Atterberg limits, XRF, and specific surface area). The studied Neogene clays are mainly calcareous silty marls with CaCO3 content ranging from 13 to 20 wt.%. The mineralogical composition showed the occurrence of quartz, calcite, feldspars, dolomite, illite, kaolinite, chlorite, and mixed-layers (10-14 Å). Cristobalite occurred only in the uppermost level of the green marls supplied from volcanic ash during the Messinian. Siderite and rhodochrosite occurred as traces pointing out to reducing or locally oxidizing conditions during sedimentation or shortly thereafter. There, marls have medium to high plasticity that is optimum for extrusion. Raw Neogene marls are suitable for structural clay products manufacturing. More specific uses were supported by geochemical results and grain-size distribution as hollow products, roofing tiles, and masonry bricks