5,331 research outputs found

    Building new income opportunities for small-farmers in Peru: the case of native and naturally colored cotton

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    In the 90's the agro-export boom of Peru, based on a market-led development, has induced a major conversion of large farms to new agribusinesses (i.e. asparagus, avocados, oranges), leaving room for expansion in the traditional agro-industrial sector (i.e. cotton) for small farmers. This study assesses the new income opportunities deriving from the reinsertion of native and naturally colored cotton (NNCC) in the agricultural production of small farmers, by means of a farm economic data analysis, scenario analysis and sensitivity analysis. The analysis has been performed in a specific case study regarding 50 farms of the Moche district in the North coast of Peru, selected by means of a non-probability sampling technique

    Reintroduction of native cotton (Gossypium Barbadian) on the North coast of Peru: analysis of economic feasibility for small producers

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    In Peru the agro-export boom has determined a major shift of large farmers from traditional agro-industrial crops (coffee and cotton) to new agribusinesses (asparagus, oranges, avocados, apples). These dynamics have left room for the small farmers to enter the traditional agro-industrial sector, or into new niche markets as in the case of native cotton. On the North coast of Peru the cultivation of the native and naturally coloured cotton (Gossypium Barbadense spp. locally called algod\uf3n El Pa\ueds) is part of the Moche indigenous culture (a local pre-Inca population). Since 1949 the Peruvian legal prohibition to produce native cotton, linked to the risk of genetic contamination of the industrial white cotton cultivations, made the keeping of these traditional varieties very difficult. Nevertheless the situation has totally changed since 2008 due to Regulation n\ub0 29224 declaring native cotton as a genetic, ethnic and cultural heritage of the country. This study analyses the economic feasibility of re-inserting the native cotton as part of the agricultural production of 50 farmers on the North coast of Peru, proposing a farm economic data analysis, scenario analysis and sensitivity analysis based on OFAT (One Factor at A Time) methodology: the results attest that in all the productive scenarios proposed (10%, 25% and 50% of the farm agricultural surface growing native cotton) the average farm incomes are going to increase. Moreover the sensitivity analysis attests that also in the worst conditions of a 10% decrease in the native cotton price, the average farm incomes with native cotton are higher compared to the business as usual scenario in all three productive scenarios proposed

    Semi-transparent Boundary Conditions in the Worldline Formalism

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    The interaction of a quantum field with a background containing a Dirac delta function with support on a surface of codimension 1 represents a particular kind of matching conditions on that surface for the field. In this article we show that the worldline formalism can be applied to this model. We obtain the asymptotic expansion of the heat-kernel corresponding to a scalar field on Rd+1\mathbb{R}^{d+1} in the presence of an arbitrary regular potential and subject to this kind of matching conditions on a flat surface. We also consider two such surfaces and compute their Casimir attraction due to the vacuum fluctuations of a massive scalar field weakly coupled to the corresponding Dirac deltas.Comment: 12 page

    A substructure analysis of the A3558 cluster complex

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    The "algorithm driven by the density estimate for the identification of clusters" (DEDICA, Pisani 1993, 1996) is applied to the A3558 cluster complex in order to find substructures. This complex, located at the center of the Shapley Concentration supercluster, is a chain formed by the ACO clusters A3556, A3558 and A3562 and the two poor clusters SC 1327-312 and SC 1329-313. We find a large number of clumps, indicating that strong dynamical processes are active. In particular, it is necessary to use a fully three-dimensional sample(i.e. using the galaxy velocity as third coordinate) in order to recover also the clumps superimposed along the line of sight. Even if a great number of detected substructures were already found in a previous analysis (Bardelli et al. 1998), this method is more efficient and faster when compared with the use of a wide battery of tests and permits the direct estimate of the detection significance. Almost all subclusters previously detected by the wavelet analyses found in the literature are recognized by DEDICA. On the basis of the substructure analysis, we also briefly discuss the origin of the A3558 complex by comparing two hypotheses: 1) the structure is a cluster-cluster collision seen just after the first core-core encounter; 2) this complex is the result of a series of incoherent group-group and cluster-group mergings, focused in that region by the presence of the surrounding supercluster. We studied the fraction of blue galaxies in the detected substructures and found that the bluest groups reside between A3562 and A3558, i.e. in the expected position in the scenario of the cluster-cluster collision.Comment: 10 pages with 12 encapsulated figures; MNRAS in pres

    Do giant barnacles contribute to deep-water biogenic reef formation in Maltese waters?

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    Deep-sea ROV surveys in the west Malta Graben allowed re-evaluation of previous work on the association of the giant barnacle, Pachylasma giganteum, with cold-water corals and other habitat-forming species, and this species’ contribution to formation of biogenic structures. While only a minor contributor to habitat architecture when anthozoans and other large sessile species are dominant, P. giganteum may become a habitat-former in the absence of competing species.peer-reviewe

    Boundaries in the Moyal plane

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    We study the oscillations of a scalar field on a noncommutative disc implementing the boundary as the limit case of an interaction with an appropriately chosen confining background. The space of quantum fluctuations of the field is finite dimensional and displays the rotational and parity symmetry of the disc. We perform a numerical evaluation of the (finite) Casimir energy and obtain similar results as for the fuzzy sphere and torus.Comment: 19 pages, 6 figures. Replaced by published versio

    The Orbital Structure of Dark Matter Halos with Gas

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    With the success of the Chandra and XMM missions and the maturation of gravitational lensing techniques, powerful constraints on the orbital structure of cluster dark matter halos are possible. I show that the X-ray emissivity and mass of a galaxy cluster uniquely specify the anisotropy and velocity dispersion profiles of its dark matter halo. I consider hydrostatic as well as cooling flow scenarios, and apply the formalism to the lensing cluster CL0024+16 and the cooling flow cluster Abell 2199. In both cases, the model predicts a parameter-free velocity dispersion profile that is consistent with independent optical redshift surveys of the clusters.Comment: 17 pages, 12 figures; to appear in the Astrophysical Journa
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