209 research outputs found

    Assessing the benefits of Andean crop diversity on farmers' livelihood: insights from a development programme in Bolivia and Peru

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    This paper analyses the impact of a development programme designed at promoting the sustainable use of Andean Grain diversity. Results demonstrate that knowledge-sharing on agronomic practices, on benefits derived from consumption, and improving Andean Grain quality had a positive impact on income generation and farmer livelihoods. These results demonstrate the effectiveness of programmes aimed at improving rural livelihoods through greater knowledge transfer and use of local agrobiodiversity, wherein private benefits may incentivise the public benefits of agrobiodiversity use and conservation. Findings warrant the need to further monitor and evaluate the potential of agrobiodiversity to improve the well-being of rural communities

    Beyond Timber: forest management models for transforming conflict into cooperation

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    This Brief is based on a report prepared for the CGIAR Research Program on Forests, Trees and Agroforestry aiming at documenting outcomes achieved by the Program’s research activities.The competing needs of different groups who depend upon the Congo Basin rainforest can be met if innovative, new research-based models for multiple-use forest management are employed.The models, together with accompanying policy guidance, have been endorsed by the region’s forest administration body COMIFAC and offer the potential to alleviate both the conflict between groups and the pressures on the landscape, allowing livelihoods and forest to flourish. Underpinned by groundbreaking, multi-disciplinary, international research, the models embody combined insights into local people’s needs, the ecologica

    Novel chemoenzymatic oxidation of amines into oximes based on hydrolase-catalysed peracid formation

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    The efficient transformation of benzylamines into the corresponding oximes has been described by means of a chemoenzymatic process. This strategy is based on a two-step sequence developed in one-pot at 30 °C and atmospheric pressure. First, the formation of a reactive peracid intermediate occurs by means of a lipase-catalysed perhydrolysis reaction, and then this peracid acts as a chemical oxidising agent of the amines. A total of nine ketoximes were isolated in high purity after a simple extraction protocol (90–98% isolated yield), while for the eleven synthesised aldoximes a further column chromatography purification was required (71–82% isolated yield). In all cases excellent selectivities were attained, offering a practical method for amine oxidation in short reaction times (1 hour). The environmental impact of the process was analysed and compared with a recently published alternative chemical synthesis, finding for this metric a good E-factor value

    Fractal-like aggregates: Relation between morphology and physical properties

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    A number of modern technological applications require a detailed calculation of the physical properties of aggregated aerosol particles. For example, in probing soot aerosols by the method called laser-induced incandescence (LII), the soot clusters are suddenly heated by a short, powerful laser pulse and then cool down to the temperature of the carrier gas. LII sizing is based on rigorous calculation of the soot aggregate heat-up and cooling and involves prediction of laser light absorption and energy and mass transfer between aggregated particles and the ambient gas. This paper describes results of numerical simulations of the mass or energy transfer between the gas and fractal-like aggregates of N spherical particles in either the free-molecular or continuum regime, as well as the light scattering properties of random fractal-like aggregates, based on Rayleigh–Debye–Gans (RDG) theory. The aggregate geometries are generated numerically using specially developed algorithms allowing “tuning” of the fractal dimension and prefactor values. Our results are presented in the form of easily applicable scaling laws, with special attention paid to relations between the aggregate gyration radius and the effective radius describing various transport processes between the aggregates and the carrier gas

    The scientific information activity of Bioversity International: the descriptor lists

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    Effective sharing of information about genetic resources depends on everyone using the same “dictionary” – which is where the descriptor lists published by Bioversity International and its partners come in. In a 2006 survey 90% or more of respondents stated that descriptor lists published by Bioversity and its partners had contributed to the development of genebank databases, increased uniformity of documentation, increased their ability to work with partners, increased efficiency in collection management, and facilitated data exchange. The utility of Bioversity’s descriptors was rated higher than those from other sources, including UPOV and USDA-GRIN, scoring an average of 3.3 on a 4-point scale. The most common constraint to using Bioversity descriptor lists was the lack of descriptors for a particular species of interest – highlighting the need for Bioversity’s continued involvement in developing additional descriptor lists

    Chemoenzymatic synthesis of optically active 2-(2- or 4-substituted-1H-imidazol-1-yl)cycloalcanols. Chiral additives for (L)-proline

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    Enantiopure substituted imidazoles obtained by enzymatic kinetic resolution can be promising candidates as co-catalysts for aldol reactions catalysed by (L)-proline. These additives seem to form supramolecular complexes with the catalyst through the formation of H-bonds, leading to significant improvement in both the reaction rates and selectivity of the reaction. Herein, we present our results on the use of these substituted trans-2-imidazoyl-cycloalkanols as additives for the (L)-proline catalyzed direct aldol reaction between ketones and aromatic aldehydes

    Toughening of complete solid solution cermets by graphite addition

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    (Ti0.95Ta0.05)(C0.5N0.5)-Co complete solid solution cermets (CSCs) were developed by a mechanochemical synthesis process and a pressureless sintering method. The effect of different percentages of graphite used as a sintering additive on the nature of the binder phase and the mechanical properties of the cermets was investigated. Microstructural and mechanical characterisations were carried out by X-ray diffraction, optical microscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, Vickers hardness, indentation fracture toughness and nanoindentation. The addition of graphite modified the carbon activity during sintering, reducing the dissolution of carbonitride ceramic particles into the molten binder. The amount of Ti and Ta remaining in the binder after sintering gradually decreased as the amount of graphite added increased, which induced a change in the nature of the binder phase. When no graphite was added, the binder consisted of the brittle TixTa1-xCo2 intermetallic phase. With the increase in the amount of graphite added, the formation of more ductile phases, such as TixTa1-xCo3 and α-Co, was observed, causing a significant improvement in the toughness of the cermets.Peer reviewe

    Hot-Pressing of (Ti, Mt)(C, N)-Co-Mo2C (Mt=Ta, Nb) powdered cermets synthesized by a mechanically induced self-sustaining reaction

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    A mechanically induced self-sustaining reaction (MSR) has been successfully employed for manufacturing powdered cermets based on Ti, Ti–Ta and Ti–Nb carbonitrides using Co as the binder phase and Mo2C as the sintering additive. The powders were sintered by hot-pressing, and complete chemical, microstructural and mechanical characterizations were performed on the densified cermets. When elemental Ta, Nb and/or Mo2C were added to the initial raw mixture submitted to the MSR process, smaller ceramic grains were observed after sintering, which suggested that ceramic particle growth was hindered by the presence of Ta, Nb and/or Mo in the host titanium carbonitride structure. Nanoindentation measurements enabled the determination of the hardness of the ceramic and binder phases, and values in the range of 26–29 GPa and 14–16 GPa were found, respectively. The high hardness values of the binder were related to the formation of intermetallic phases.Gobierno de España European Regional Development No. MAT2011- 2298

    Understanding the economic impact of BXW and its management practices in East and Central Africa

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    Banana Xanthomonas wilt (BXW) is a widespread banana disease in East and Central Africa (ECA). It has the ability to cause up to 100% yield loss, severely compromising food security and livelihoods for banana-based farming households. There are no BXW-resistant varieties, and cultural management practices offer the only means of control. However, adoption of these practices by farmers has been lower than expected, mainly because of their high cost and labour-intensiveness. There are also other actors, both in public and private sectors, playing an important role in the disease management and facing different costs related to it. Our literature review reveals that a cost analysis of the banana value chain as a whole is missing. By this we mean consideration of not only farmers, who have to sustain the cost of management practices, but also other stakeholders involved, as national and local governments, research institutions and agricultural extensionists. In this study we identify economic actors involved in the banana value chain together with their costs related to the disease management and propose a cost analysis conceptual framework. Further, we review determinants of adoption of the BXW management practices and finally relate them to the estimates of costs of inaction (losses due to BXW spread). In this way, we present a comprehensive picture of costs of BXW spread vis-a-vis the costs of management practices and indicate possible ways to tip the balance in favour of the disease eradication. Ongoing research needs to carry out ex-post analyses on different costs sustained by the stakeholders of banana value chain, and ex ante analyses to predict future scenarios which represent possible alternatives, depending on whether and how the disease will be managed in the coming years. Those results will better inform decision-makers at national, regional, and international levels and provide support in designing strategies to cope with the BXW spread across the ECA region
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