767 research outputs found

    Diversity and conservation of traditional African vegetables: Priorities for action

    Get PDF
    © 2020 The Authors. Diversity and Distributions published by John Wiley & Sons Ltd.Aim: Traditional African vegetables have high potential to contribute to healthy diets and climate resilience in sub-Saharan African food systems. However, their genetic resources are likely at threat because they are underutilized and under the radar of agricultural research. This paper aims to contribute to a conservation agenda for traditional African vegetables by examining the geographical diversity and conservation status of these species. Location: Sub-Saharan Africa. Methods: 126 traditional annual and perennial African vegetables were selected for their food and nutrition potential. Food uses and species’ areas of origin were recorded from literature. Species’ presence records were collected from open-access databases of genebanks and herbaria. These records were used to determine geographical patterns of observed and modelled richness, to distinguish geographical clusters with different compositions of vegetables, to assess species’ ex situ and in situ conservation status and to prioritize countries for conservation actions. Results: Of the 126 species, 79 originated in sub-Saharan Africa. High levels of observed and modelled species richness were found in: (a) West Tropical Africa in Ghana, Togo and Benin; (b) West-Central Tropical Africa in South Cameroon; (c) Northeast and East Tropical Africa in Ethiopia and Tanzania; and (d) Southern Africa in Eswatini. South Sudan, Angola and DR Congo are potential areas of high species richness that require further exploration. In general, ex situ conservation status of the selected species was poor compared to their in situ conservation status. Main conclusions: Areas of high species richness in West Tropical Africa, South Cameroon and Ethiopia coincide with centres of crop domestication and cultural diversity. Hotspots of diversity in Tanzania and Eswatini are especially rich in wild vegetables. Addressing the conservation of vegetable diversity in West Tropical Africa and South Cameroon is of most urgent concern as vegetable genetic resources from these locations are least represented in ex situ collections.publishedVersio

    No significant improvement of cardiovascular disease risk indicators by a lifestyle intervention in people with familial hypercholesterolemia compared to usual care: results of a randomised controlled trial

    Get PDF
    Background: People with Familial Hypercholesterolemia (FH) may benefit from lifestyle changes supporting their primary treatment of dyslipidaemia. This project evaluated the efficacy of an individualised tailored lifestyle intervention on lipids (low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), total cholesterol (TC) and triglycerides), systolic blood pressure, glucose, body mass index (BMI) and waist circumference in people with FH. Methods: Adults with FH (n= 340), recruited from a Dutch cascade screening program, were randomly assigned to either a control group or an intervention group. The personalised intervention consisted of web-based tailored lifestyle advice and personal counselling. The control group received care as usual. Lipids, systolic blood pressure, glucose, BMI, and waist circumference were measured at baseline and after 12 months. Regression analyses were conducted to examine differences between both groups. Results: After 12 months, no significant between-group differences of cardiovascular disease (CVD) risk indicators were observed. LDL-C levels had decreased in both the intervention and control group. This difference between intervention and control group was not statistically significant. Conclusions: This project suggests that an individually tailored lifestyle intervention did not have an additional effect in improving CVD risk indicators among people with FH. The cumulative effect of many small improvements in all indicators on long term CVD risk remains to be assessed in future studies. Trial registration: NTR1899 at ww.trialregister.nl.© 2012 Broekhuizen et al

    Centennial-scale elemental and isotopic variability in the tropical and subtropical North Atlantic Ocean

    Get PDF
    Thesis (Ph.D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2002.Includes bibliographical references (leaves 169-187).The marine geochemistry of the North Atlantic Ocean varies on decadal to centennial time scales, a consequence of natural and anthropogenic forcing. Surface corals provide a useful geochemical archive to quantify past mixed layer variability, and this study presents elemental and isotopic records from the tropical and subtropical North Atlantic. A consistent method for stable lead isotope analysis via multiple collector ICP-MS is first presented. This method is then applied to western North Atlantic surface corals and seawater, constraining historical elemental and isotopic lead variability. Six stable lead isotope profiles are developed from the western and eastern North Atlantic, demonstrating consistent mixed layer, thermocline, and deep water variability. Finally, coralline trace element records, including cadmium, barium, and lead, are presented from the Cariaco Basin. First, a reliable method is developed for stable lead isotope analysis by multiple collector ICP-MS. This study presents new observations of the large (0.7% amu-l), time-dependent mass fractionation determined by thallium normalization, including preferential light ion transmission induced by the acceleration potential and nebulizer conditions. These experiments show equivalent results for three empirical correction laws, and the previously proposed [beta]Pb/[beta]TI correction does not improve isotope ratio accuracy under these conditions. External secondary normalization to SRM-981 provides one simple alternative, and a rationale is provided for this correction. With current intensities less than 1.5x10-12 A, external isotope ratio precision less than 200 ppm is observed (2[sigma]). Matrix effects are significant with concomitant calcium in SRM-981 (-280 ppm at 257 [mu]M [Ca]).(cont.) With the appropriate corrections and minimal concomitants, MC-ICP-MS can reliably determine 206Pb/207Pb and 208Pb/207Pb ratios of marine carbonates and seawater. Anthropogenic lead represents a promising transient oceanographic tracer, and its historical isotopic and elemental North Atlantic variability have been documented by proxy reconstructions and seawater observations. Two high-resolution surface coral and seawater time series from the western North Atlantic are presented, demonstrating past variability consistent with upper ocean observations. The elemental reconstruction suggests the primary lead transient was advected to the western North Atlantic from 1955 to 1968, with an inferred maximum lead concentration of 205 pmol kg-1 in 1971. The mean 1999 North Atlantic seawater concentration (38 pmol kg-1) is equivalent to 1905, several decades prior to the initial consumption of leaded gasoline in the United States. A 206Pb/207Pb transient from 1968 to 1990 is also observed, lagging the elemental transient by ten years. The provenance of this isotopic record is distinct from Arctic and European ice core observations and supports a 40% ...by Matthew K. Reuer.Ph.D

    Suitability of key Central American agroforestry species under future climates: an Atlas.

    Get PDF
    This atlas provides habitat suitability maps for 54 species that are widely used in Central America for shade in coffee or cocoa agroforestry systems. The 54 species represent 24 fruit species, 24 timber species and 6 species used for soil fertility improvement. Suitability maps correspond to the baseline climate (1960-1990) and 2050 climates predicted for Representative Concentration Pathways (RCP) 4.5 and 8.5. Habitat was classified as suitable in future climates if a minimum of 12 out of 17 downscaled Global Circulation Models predicted suitable climates. Details of the methodology of ensemble suitability modelling with the BiodiversityR package are provided in the atlas. The atlas was developed to support climate change oriented initiatives for diversification and conservation of forest genetic resources across Central America. Farmers, scientists and technicians can use the atlas to identify suitable and vulnerable areas for shade species and develop strategies for climate change adaptation. This work has been possible by the financial support of the CGIAR research program on Forests, Trees and Agroforestry (FTA; supported by the CGIAR Fund Donors); the CGIAR research program on Climate Change Agriculture and Food Security (CCAFS; supported by the CGIAR Fund Donors) and HIVOS. The authors of this atlas are scientists of Bioversity International, CATIE and the World Agroforestry Centre

    Force steps during viral DNA packaging ?

    Get PDF
    Biophysicists and structural biologists increasingly acknowledge the role played by the mechanical properties of macromolecules as a critical element in many biological processes. This change has been brought about, in part, by the advent of single molecule biophysics techniques that have made it possible to exert piconewton forces on key macromolecules and observe their deformations at nanometer length scales, as well as to observe the mechanical action of macromolecules such as molecular motors. This has opened up immense possibilities for a new generation of mechanical investigations that will respond to such measurements in an attempt to develop a coherent theory for the mechanical behavior of macromolecules under conditions where thermal and chemical effects are on an equal footing with deterministic forces. This paper presents an application of the principles of mechanics to the problem of DNA packaging, one of the key events in the life cycle of bacterial viruses with special reference to the nature of the internal forces that are built up during the DNA packaging process.Comment: 18 pages, 7 figures, To appear in the Journal of Mechanics and Physics of Solid

    Final

    Get PDF
    The present report reviews the fundamental right to privacy and data protection which shall be assured to individuals and the Directive 95/46/EC which provides more detailed rules on how to establish protection in the case of biometric data processing. The present framework does not seem apt to cope with all issues and problems raised by biometric applications. The limited recent case law of the European Court of Human Rights and the Court of Justice sheds some light on some relevant issues, but does not answer all questions. The report provides an analysis of the use of biometric data and the applicable current legal framework in six countries. The research demonstrates that in various countries, position is taken against the central storage of biometric data because of the various additional risks such storage entails. Furthermore, some countries stress the risks of the use of biometric characteristics which leave traces (such as e.g., fingerprint, face, voice
). In general, controllers of biometric applications receive limited clear guidance as to how implement biometric applications. Because of conflicting approaches, general recommendations are made in this report with regard to the regulation of central storage of biometric data and various other aspects, including the need for transparency of biometric systems

    DNA metabarcoding unveils multiscale trophic variation in a widespread coastal opportunist

    Get PDF
    A thorough understanding of ecological networks relies on comprehensive information on trophic relationships among species. Since unpicking the diet of many organisms is unattainable using traditional morphology‐based approaches, the application of high‐throughput sequencing methods represents a rapid and powerful way forward. Here, we assessed the application of DNA metabarcoding with nearly universal primers for the mitochondrial marker cytochrome c oxidase I in defining the trophic ecology of adult brown shrimp, Crangon crangon, in six European estuaries. The exact trophic role of this abundant and widespread coastal benthic species is somewhat controversial, while information on geographical variation remains scant. Results revealed a highly opportunistic behaviour. Shrimp stomach contents contained hundreds of taxa (>1,000 molecular operational taxonomic units), of which 291 were identified as distinct species, belonging to 35 phyla. Only twenty ascertained species had a mean relative abundance of more than 0.5%. Predominant species included other abundant coastal and estuarine taxa, including the shore crab Carcinus maenas and the amphipod Corophium volutator. Jacobs’ selectivity index estimates based on DNA extracted from both shrimp stomachs and sediment samples were used to assess the shrimp's trophic niche indicating a generalist diet, dominated by crustaceans, polychaetes and fish. Spatial variation in diet composition, at regional and local scales, confirmed the highly flexible nature of this trophic opportunist. Furthermore, the detection of a prevalent, possibly endoparasitic fungus (Purpureocillium lilacinum) in the shrimp's stomach demonstrates the wide range of questions that can be addressed using metabarcoding, towards a more robust reconstruction of ecological networks
    • 

    corecore