1,374 research outputs found

    Towards the implementation of a sustainable cold chain for the livestock value chain in Bangladesh

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    The cold chain is essential for food quality and safety. Good management of the postharvest cold chain can reduce food losses. The International Institute of Refrigeration (IIR) estimated that the lack of a cold chain causes significant global food losses of up to 20% of the global food supply (IIR, 2009). Besides economic and health considerations, the environmental sustainability of the food cold supply chain should be considered to prevent further increases in emissions that could potentially increase global warming. This paper presents an assessment of the livestock cold chain related gaps in Bangladesh which is one of the initiative within the World Bank LDDP (Livestock and Dairy Development Project) project (LDDP, P161246). Information on technological and non-technological issues which can be tackled are presented. Practical recommendations to develop the cold chain in Bangladesh for milk and meat are provided

    Non-local scaling in two-dimensional gravitational clustering

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    Using an ensemble of high resolution 2D numerical simulations, we explore the scaling properties of cosmological density fluctuations in the non-linear regime. We study the scaling behaviour of the usual NN--point volume-averaged correlations, and also examine the scaling of the entire probability density function (pdf) of the fluctuations. We focus on two important issues: (i) whether the scaling behaviour of 2D clustering is consistent with what one infer from radial collapse arguments; and (ii) whether there is any evidence from these high-resolution simulations that a regime of stable clustering is ever entered. We find that the answers are (i) yes and (ii) no. We further find that the behaviour of the highly non-linear regime in these simulations suggests the existence of a regime where the correlation function is independent of the initial power spectrum.Comment: 5 pages, Latex file, 2 Postscript Figure

    Cosmic Shear Analysis with CFHTLS Deep data

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    We present the first cosmic shear measurements obtained from the T0001 release of the Canada-France-Hawaii Telescope Legacy Survey. The data set covers three uncorrelated patches (D1, D3 and D4) of one square degree each observed in u*, g', r', i' and z' bands, out to i'=25.5. The depth and the multicolored observations done in deep fields enable several data quality controls. The lensing signal is detected in both r' and i' bands and shows similar amplitude and slope in both filters. B-modes are found to be statistically zero at all scales. Using multi-color information, we derived a photometric redshift for each galaxy and separate the sample into medium and high-z galaxies. A stronger shear signal is detected from the high-z subsample than from the low-z subsample, as expected from weak lensing tomography. While further work is needed to model the effects of errors in the photometric redshifts, this results suggests that it will be possible to obtain constraints on the growth of dark matter fluctuations with lensing wide field surveys. The various quality tests and analysis discussed in this work demonstrate that MegaPrime/Megacam instrument produces excellent quality data. The combined Deep and Wide surveys give sigma_8= 0.89 pm 0.06 assuming the Peacock & Dodds non-linear scheme and sigma_8=0.86 pm 0.05 for the halo fitting model and Omega_m=0.3. We assumed a Cold Dark Matter model with flat geometry. Systematics, Hubble constant and redshift uncertainties have been marginalized over. Using only data from the Deep survey, the 1 sigma upper bound for w_0, the constant equation of state parameter is w_0 < -0.8.Comment: 14 pages, 16 figures, accepted A&

    Observational signatures of the weak lensing magnification of supernovae

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    Due to the deflection of light by density fluctuations along the line of sight, weak lensing is an unavoidable systematic uncertainty in the use of type Ia supernovae (SNe Ia) as cosmological distance indicators. We derive the expected weak lensing signatures of SNe Ia by convolving the intrinsic distribution in SN Ia peak luminosity with magnification distributions of point sources. We analyze current SN Ia data, and find marginal evidence for weak lensing effects. The statistics is poor because of the small number of observed SNe Ia. Future observational data will allow unambiguous detection of the weak lensing effect of SNe Ia. The observational signatures of weak lensing of SNe Ia that we have derived provide useful templates with which future data can be compared.Comment: Including 4 color figures. Expanded and modified version. JCAP accepte

    Non-adiabatic primordial fluctuations

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    We consider general mixtures of isocurvature and adiabatic cosmological perturbations. With a minimal assumption set consisting of the linearized Einstein equations and a primordial perfect fluid we derive the second-order action and its curvature variables. We also allow for varying equation of state and speed of sound profiles. The derivation is therefore carried out at the same level of generality that has been achieved for adiabatic modes before. As a result we find a new conserved super-horizon quantity and relate it to the adiabatically conserved curvature perturbation. Finally we demonstrate how the formalism can be applied by considering a Chaplygin gas-like primordial matter model, finding two scale-invariant solutions for structure formation.Comment: 11 page

    Women’s Empowerment in Action: Evidence from a Randomized Control Trial in Africa €

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    Women in developing countries are disempowered relative to their contemporaries in developed countries. High youth unemployment and early marriage and childbearing interact to limit human capital investment and enforce dependence on men. In this paper we evaluate an attempt to jump-start adolescent women’s empowerment in the world’s second youngest country: Uganda. In this two-pronged intervention, adolescent girls are simultaneously provided vocational training and information on sex, reproduction and marriage. Relative to adolescents in control communities, after two years the intervention raises the likelihood that girls engage in income generating activities by 72 % (mainly driven by increased participation in self-employment), and raises their monthly consumption expenditures by 41%. Teen pregnancy falls by 26%, and early entry into marriage/cohabitation falls by 58%. Strikingly, the share of girls reporting sex against their will drops from 14 % to almost half that level and preferred ages of marriage and childbearing both move forward. The 
ndings indicate that women’s economic and social empowerment can be jump-started through the combined provision of vocational and life skills, and is not necessarily held back by insurmountable constraints arising from binding social norms. JEL Classi
cations: I25, J13, J24, O12
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