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As anthropogenic degradation of biodiversity and ecosystems increases, so does the potential threat to the supply of ecosystem services, a key contribution of nature to people. Biodiversity has often been used in spatial conservation planning and has been regarded as one among multiple services delivered by ecosystems. Hence, biodiversity conservation planning should be integrated in a framework of prioritizing services in order to inform decision-making. Here, we propose a prioritization approach based on scenarios maximising both the provision of ecosystem services and the conservation of biodiversity hotspots. Different weighting scenarios for the α-diversity in four taxonomic groups and 10 mapped ecosystem services were used to simulate varying priorities of policymakers in a mountain region. Our results illustrate how increasing priorities to ecosystem services can be disadvantageous to biodiversity. Moreover, the analysis to identify priority areas that best compromise the conservation of α-diversity and ecosystem services are predominantly not located within the current protected area network. Our analyses stress the need for an appropriate weighting of biodiversity within decision making that seek to integrate multiple ecosystem services. Our study paves the way toward further integration of multiple biodiversity groups and components, ecosystem services and various socio-economic scenarios, ultimately fuelling the development of more informed, evidence-based spatial planning decisions for conservation.

Introduction La dystonie est definie par une contraction musculaire anormale responsable de mouvements ou de postures anormales. La forme monogenique la plus frequente est la DYT1 liee au gene TOR1A. Objectifs Determiner la frequence de la dystonie DYT1 chez des patients algeriens. Patients et methodes Nous rapportons une serie de 9 patients âges de 12 a 43 ans presentant une dystonie isolee ou combinee, a debut precoce, d’allure primitive. Tous les patients ont beneficie d’une etude moleculaire a la recherche de la mutation recurrente du gene DYT1 et d’une prise en charge therapeutique medicale notamment une substitution dopaminergique et ou un traitement chirurgicale (stimulation pallidale). Resultats La dystonie etait generalisee isolee dans 6 cas, associant une dystonie crânienne et ou laryngee dans 4 cas. Elle etait combinee dans 3 cas. L’etude moleculaire a revele l’absence chez tous les patients de la mutation recurrente c.907delGAG dans l’exon 5 du gene DYT1 (TOR1A). Sur le plan therapeutique la sustitution dopaminergique a ete spectaculaire dans 2 cas sur 9 et la stimulation pallidale dans 1 cas sur 4. Discussion Devant toute dystonie isolee, il convient toujours de rechercher en premiere intention la mutation du gene DYT1 du fait de sa relative frequence. Toutefois, le tableau clinique est non specifique et souvent comparable a celui des formes non DYT1 notamment la DYT6 caracterisee par une dystonie crânienne et laryngee associee, ceci rend compte de l’heterogeneite genetique des dystonies primitives non dopa sensibles. Conclusion La DYT1 est decrite comme la plus frequente des dystonies monogeniques mais cela ne semble pas etre le cas de notre cohorte. Une serie plus importante est necessaire pour juger de sa frequence en Algerie.

The aim of this study was to find out if field boundaries are refuges for earthworms from where they can spread out into the agricultural fields, thereby keeping up their abundance and biodiversity. The earthworm community was studied in: (1) a 640 m long field boundary; (2) the adjacent arable field at different distances from the boundary; (3) a pasture adjoining to the opposite side of the field near Uppsala in Sweden. Sampling was done in May and September. In contradiction to what was preconceived, the abundance and biomass of earthworms, both in the boundary and the pasture, was significantly lower than that in the agricultural field. The density increased towards the centre of the field. The trends were similar for both spring and autumn. The same species were found in the field, boundary and pasture, but Aporrectodea caliginosa was more dominant in the field than in the other habitats. The conclusion is that agriculture with manure, fertilisers, moderate soil cultivation and varying crops, in general, is favourable for earthworms, except for certain species. However, situations can occur when the earthworm populations in the field decline, and then boundaries may serve as sources from where re-immigration can take place.

The synthesis of C-cyclopurine and C-cyclodihydropyrimidine nucleosides has been effected using 5′-aryltelluronucleosides. Generation of methyl radicals from the photolysis of the acetyl derivative of N-hydroxy-2-thiopyridone permitted, by radical exchange, the formation of 5′-nucleoside radicals which cyclized in satisfactory yields.