3,988 research outputs found

    FOOD-FOR-WORK FOR POVERTY REDUCTION AND THE PROMOTION OF SUSTAINABLE LAND USE: CAN IT WORK?

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    Food-for-work (FFW) programs are commonly used both for short-term relief and long-term development purposes. In the latter capacity, they are increasingly used for natural resources management projects. Barrett, Holden and Clay (forthcoming) assess the suitability of FFW programs as insurance to cushion the poor against short-term, adverse shocks that could, in the absence of a safety net, have permanent repercussions. In this paper we explore the complementary question of FFW programs' potential to reduce poverty and promote sustainable land use in the longer run through induced changes in investment patterns. FFW programs commonly aim to produce or maintain potentially valuable public goods necessary to stimulate productivity and thus income growth. Among the most common projects are road building, reforestation, and the installation of terracing or irrigation. In the abstract, public goods such as these are unambiguously good. There is a danger, however, that such programs could discourage private soil and water conservation and crowd out private investment. How important are such effects and when are these effects small or large and when and how can they be reduced? How do market characteristics, timing and design of FFW programs affect this? When, where and how can FFW programs more efficiently reduce poverty and promote more sustainable land management? The paper aims to answer these questions. Much recent empirical research has focused on the shorter-term targeting issue of whether FFW and related workfare programs efficiently target the poor (Dev 1995, Von Braun 1995, Webb 1995, Subbarao 1997, Clay et al. 1998, Devereux 1999, Jayne et al. 1999, Ravallion 1999, Teklu and Asefa 1999, Atwood et al. 2000, Gebremedhin and Swinton 2000, Haddad and Adato 2001, Jalan and Ravallion 2001). Much less research has been focused on the longer-term effects of FFW. Yet the large share of hunger worldwide arises due to chronic deprivation and vulnerability, not short-term shocks (Speth 1993, Barrett 2002). Also most of the FFW programs in Ethiopia have long-term development goals and are formally distinguished from the disaster relief FFW programs (Aas and Mellemstrand 2002). It is therefore appropriate to evaluate these programs based on their long-term goals and not only on the basis of short-term targeting. In a case study in Tigray Aas and Mellemstrand (2002) found that the FFW recipients considered the long-term benefits of FFW as more important than the short-term benefits of food provision. FFW programs may produce valuable public goods. For example, Von Braun et al. (1999) report multiplier effects of a FFW-built road in the Ethiopian lowlands. Public provision of public goods may be socially desirable because private investment in soil and water conservation and tree planting may be well below socially optimal levels due to poverty and market imperfections (Holden, Shiferaw and Wik 1998, Holden and Shiferaw 2002, Holden and Yohannes 2002, Pender and Kerr 1998), tenure insecurity (Gebremedhin and Swinton 2000, Holden, Benin, Shiferaw and Pender 2003), lack of technical knowledge and coordination problems across farms (Hagos and Holden 2002). There is, however, also a danger that FFW programs crowd out private investments (Gebremedhin and Swinton 2000). We analyze these issues using multiple methods. First, section II introduces a simple theoretical framework for understanding the analytically ambiguous effects of FFW programs on sustainable land use patterns. We first present the basic intuition in a static framework to illustrate the selection, crowding out and targeting issues, before generalizing it to a dynamic model to illustrate the possible insurance and crowding in effects of FFW. Section III then uses an applied, dynamic bio-economic farm household model applied to a less-favoured area in Ethiopia to investigate via numerical simulation how household welfare and land use patterns vary with changes in environmental and FFW program design parameters. Section IV presents econometric evidence based on survey panel data from northern Ethiopia to assess the relationship between FFW and private investment in conservation. Section V discusses our findings and fleshes them out a bit with further empirical evidence. Section VI concludes.Food Security and Poverty, Q18, O1, Q2, I1,

    In-Plane Spectral Weight Shift of Charge Carriers in YBa2Cu3O6.9YBa_2Cu_3O_{6.9}

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    The temperature dependent redistribution of the spectral weight of the CuO2CuO_2 plane derived conduction band of the YBa2Cu3O6.9YBa_2Cu_3O_{6.9} high temperature superconductor (T_c = 92.7 K) was studied with wide-band (from 0.01 to 5.6 eV) spectroscopic ellipsometry. A superconductivity - induced transfer of the spectral weight involving a high energy scale in excess of 1 eV was observed. Correspondingly, the charge carrier spectral weight was shown to decrease in the superconducting state. The ellipsometric data also provide detailed information about the evolution of the optical self-energy in the normal and superconducting states

    Enhanced nasopharyngeal infection and shedding associated with an epidemic lineage of emm3 group A Streptococcus

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    Background: A group A Streptococcus (GAS) lineage of genotype emm3, sequence type 15 (ST15) was associated with a six month upsurge in invasive GAS disease in the UK. The epidemic lineage (Lineage C) had lost two typical emm3 prophages, Φ315.1 and Φ315.2 associated with the superantigen ssa, but gained a different prophage (ΦUK-M3.1) associated with a different superantigen, speC and a DNAse spd1. Methods and Results: The presence of speC and spd1 in Lineage C ST15 strains enhanced both in vitro mitogenic and DNAse activities over non-Lineage C ST15 strains. Invasive disease models in Galleria mellonella and SPEC-sensitive transgenic mice, revealed no difference in overall invasiveness of Lineage C ST15 strains compared to non-Lineage C ST15 strains, consistent with clinical and epidemiological analysis. Lineage C strains did however markedly prolong murine nasal infection with enhanced nasal and airborne shedding compared to non-Lineage C strains. Deletion of speC or spd1 in two Lineage C strains identified a possible role for spd1 in airborne shedding from the murine nasopharynx. Conclusions: Nasopharyngeal infection and shedding of Lineage C strains was enhanced compared to nonLineage C strains and this was, in part, mediated by the gain of the DNase spd1 through prophage acquisition

    EVIDENCE OF SUPPRESSOR CELL ACTIVITY IN SPLEENS OF MICE BEARING PRIMARY TUMORS INDUCED BY MOLONEY SARCOMA VIRUS

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    Spleens from Moloney sarcoma virus (MSV) tumor-bearing C57BL/6N mice contained four times the normal number of mononuclear cells and displayed a markedly elevated "spontaneous" (mitogen-independent) DNA synthesis on a per cell basis. The number of macrophages were increased three-fold while there was a slight reduction in the percentage of T lymphocytes. The phytohemagglutinin (PHA) response on a per cell basis of spleens from tumor-bearing mice was decreased about 90% when compared with normal control mice. The primary in vitro immune response to sheep red blood cells was also suppressed to levels of less than 10% of normals. The PHA response could be restored by purification of MSV spleen cells by rayon adherence columns and by removal of phagocytic cells by an iron/magnet technique. The activity of suppressor cells in MSV spleens was demonstrated in mixtures with syngeneic normal spleen cells where a marked impairment of the PHA response was observed. Spleen cells from tumor-free nude mice and normal spleen cells treated by anti-θ serum plus guinea pig complement (C'), both totally unreactive to PHA, had no such effect. The inhibitor cell in MSV spleens was shown to be insensitive to inactivation by anti-θ plus C', but could be removed by the adherence columns and the iron/magnet technique. These data suggest that this suppressor cell is a cell of the monocyte/macrophage series. Suggestive evidence was also presented that the suppressor cells belong to a proliferating population in MSV spleens. Similar suppressor cells have been previously demonstrated in spleens of mice during a variety of immune responses. Our data show, that a tumor, although stimulating the immune system, nevertheless may be suppressive on certain immune functions through the activation of suppressor cells

    Assessing the economic and environmental impacts of conservation technologies: a farm-level bioeconomic modelling approach

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    This chapter illustrates how a multiperiod bioeconomic household-level model, in which changes in resource quality have feedback effects on future land productivity, can be used to explore the economic and environmental impacts of natural resource management technologies and policies. This model is used to test the influence of land scarcity and asset poverty on incentives to undertake sustainability investments in Andit Tid, in the central highlands of Ethiopia. The results show how land scarcity could drive conservation investments, while poverty in vital assets such as oxen and labour could deter investments in land and water management. The welfare and environmental impacts are very modest but are highest when the conservation technology does not reduce short-term crop yields. Otherwise, the level of adoption of these technologies and their effects on poverty and soil degradation are significantly reduced even when family labour is not limitin

    Solving One Dimensional Scalar Conservation Laws by Particle Management

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    We present a meshfree numerical solver for scalar conservation laws in one space dimension. Points representing the solution are moved according to their characteristic velocities. Particle interaction is resolved by purely local particle management. Since no global remeshing is required, shocks stay sharp and propagate at the correct speed, while rarefaction waves are created where appropriate. The method is TVD, entropy decreasing, exactly conservative, and has no numerical dissipation. Difficulties involving transonic points do not occur, however inflection points of the flux function pose a slight challenge, which can be overcome by a special treatment. Away from shocks the method is second order accurate, while shocks are resolved with first order accuracy. A postprocessing step can recover the second order accuracy. The method is compared to CLAWPACK in test cases and is found to yield an increase in accuracy for comparable resolutions.Comment: 15 pages, 6 figures. Submitted to proceedings of the Fourth International Workshop Meshfree Methods for Partial Differential Equation

    Superclustering at Redshift Z=0.54

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    We present strong evidence for the existence of a supercluster at a redshift of z=0.54 in the direction of Selected Area 68. From the distribution of galaxies with spectroscopic redshifts we find that there is a large over-density of galaxies (a factor of four over the number expected in an unclustered universe) within the redshift range 0.530 < z < 0.555. By considering the spatial distribution of galaxies within this redshift range (using spectroscopic and photometric redshifts) we show that the galaxies in SA68 form a linear structure passing from the South-West of the survey field through to the North-East (with a position angle of approximately 35 deg East of North). This position angle is coincident with the positions of the X-ray clusters CL0016+16, RX J0018.3+1618 and a new X-ray cluster, RX J0018.8+1602, centered near the radio source 54W084. All three of these sources are at a redshift of approximately z=0.54 and have position angles, derived from their X-ray photon distributions, consistent with that measured for the supercluster. Assuming a redshift of 0.54 for the distribution of galaxies and a FWHM dispersion in redshift of 0.020 this represents a coherent structure with a radial extent of 31 Mpc, transverse dimension of 12 Mpc, and a thickness of approximately 4 Mpc. The detection of this possible supercluster demonstrates the power of using X-ray observations, combined with multicolor observations, to map the large scale distribution of galaxies at intermediate redshifts.Comment: 12 pages, 3 figures, Latex, aaspp4.sty, accepted for publication in Ap J Letters. Figure 3 and followup observations can be found at http://tarkus.pha.jhu.edu/~ajc/papers/supercluster

    Complex Patterns in Reaction-Diffusion Systems: A Tale of Two Front Instabilities

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    Two front instabilities in a reaction-diffusion system are shown to lead to the formation of complex patterns. The first is an instability to transverse modulations that drives the formation of labyrinthine patterns. The second is a Nonequilibrium Ising-Bloch (NIB) bifurcation that renders a stationary planar front unstable and gives rise to a pair of counterpropagating fronts. Near the NIB bifurcation the relation of the front velocity to curvature is highly nonlinear and transitions between counterpropagating fronts become feasible. Nonuniformly curved fronts may undergo local front transitions that nucleate spiral-vortex pairs. These nucleation events provide the ingredient needed to initiate spot splitting and spiral turbulence. Similar spatio-temporal processes have been observed recently in the ferrocyanide-iodate-sulfite reaction.Comment: Text: 14 pages compressed Postscript (90kb) Figures: 9 pages compressed Postscript (368kb

    PALEO-PGEM v1.0: a statistical emulator of Pliocene–Pleistocene climate

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    We describe the development of the “Paleoclimate PLASIM-GENIE (Planet Simulator–Grid-Enabled Integrated Earth system model) emulator” PALEO-PGEM and its application to derive a downscaled high-resolution spatio-temporal description of the climate of the last 5×106 years. The 5×106-year time frame is interesting for a range of paleo-environmental questions, not least because it encompasses the evolution of humans. However, the choice of time frame was primarily pragmatic; tectonic changes can be neglected to first order, so that it is reasonable to consider climate forcing restricted to the Earth's orbital configuration, ice-sheet state, and the concentration of atmosphere CO2. The approach uses the Gaussian process emulation of the singular value decomposition of ensembles of the intermediate-complexity atmosphere–ocean GCM (general circulation model) PLASIM-GENIE. Spatial fields of bioclimatic variables of surface air temperature (warmest and coolest seasons) and precipitation (wettest and driest seasons) are emulated at 1000-year intervals, driven by time series of scalar boundary-condition forcing (CO2, orbit, and ice volume) and assuming the climate is in quasi-equilibrium. Paleoclimate anomalies at climate model resolution are interpolated onto the observed modern climatology to produce a high-resolution spatio-temporal paleoclimate reconstruction of the Pliocene–Pleistocene

    Building professional discourse in emerging markets: Language, context and the challenge of sensemaking

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    Using ethnographic evidence from the former Soviet republics, this article examines a relatively new and mainly unobserved in the International Business (IB) literature phenomenon of communication disengagement that manifests itself in many emerging markets. We link it to the deficiencies of the local professional business discourse rooted in language limitations reflecting lack of experience with the market economy. This hampers cognitive coherence between foreign and local business entities, adding to the liability of foreignness as certain instances of professional experience fail to find adequate linguistic expression, and complicates cross-cultural adjustments causing multi-national companies (MNCs) financial losses. We contribute to the IB literature by examining cross-border semantic sensemaking through a retrospectively constructed observational study. We argue that a relative inadequacy of the national professional idiom is likely to remain a feature of business environment in post-communist economies for some time and therefore should be factored into business strategies of MNCs. Consequently, we recommend including discursive hazards in the risk evaluation of international projects
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