1,374 research outputs found
Towards the implementation of a sustainable cold chain for the livestock value chain in Bangladesh
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
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 --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
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Stellar metallicity gradients of Local Group dwarf galaxies
Aims. We explore correlations between the strength of metallicity gradients in Local Group dwarf galaxies and their stellar mass, star formation history timescales, and environment. Methods. We performed a homogeneous analysis of literature spectroscopic data of red giant stars and determined radial metallicity profiles for 30 Local Group dwarf galaxies. This is the largest compilation of this type to date. Results. The dwarf galaxies in our sample show a variety of metallicity profiles, most of them decreasing with radius and some with rather steep profiles. The derived metallicity gradients as a function of the half-light radius, [Fe/H](R/Re), show no statistical differences when compared with the morphological type of the galaxies, nor with their distance from the Milky Way or M31. No correlations are found with either stellar mass or star formation timescales. In particular, we do not find the linear relation between [Fe/H](R/Re) and the galaxy median age t50, which has been reported in the literature for a set of simulated systems. On the other hand, the high angular momentum in some of our galaxies does not seem to affect the gradient strengths. The strongest gradients in our sample are observed in systems that are likely to have experienced a past merger event. When these merger candidates are excluded, the analysed dwarf galaxies show mild gradients (ĂŁ-0.1 dex Re-1) with little scatter between them, regardless of their stellar mass, dynamical state, and their star formation history. These results agree well with different sets of simulations presented in the literature that were analysed using the same method as for the observed dwarf galaxies. Conclusions. The interplay between the multitude of factors that could drive the formation of metallicity gradients likely combine in complex ways to produce in general comparable mild [Fe/H](R/Re) values, regardless of stellar mass and star formation history. The strongest driver of steep gradients seems to be previous dwarf-dwarf merger events in a system
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A novel rapid-onset high-penetrance plasmacytoma mouse model driven by deregulation of cMYC cooperating with KRAS12V in BALB/c mice
Our goal is to develop a rapid and scalable system for functionally evaluating deregulated genes in multiple myeloma (MM). Here, we forcibly expressed human cMYC and KRAS12V in mouse T2 B cells (IgM+B220+CD38+IgD+) using retroviral transduction and transplanted these cells into lethally irradiated recipient mice. Recipients developed plasmacytomas with short onset (70 days) and high penetrance, whereas neither cMYC nor KRAS12V alone induced disease in recipient mice. Tumor cell morphology and cell surface biomarkers (CD138+B220âIgMâGFP+) indicate a plasma cell neoplasm. Gene set enrichment analysis further confirms that the tumor cells have a plasma cell gene expression signature. Plasmacytoma cells infiltrated multiple loci in the bone marrow, spleen and liver; secreted immunoglobulins; and caused glomerular damage. Our findings therefore demonstrate that deregulated expression of cMYC with KRAS12V in T2 B cells rapidly generates a plasma cell disease in mice, suggesting utility of this model both to elucidate molecular pathogenesis and to validate novel targeted therapies
Cosmic Shear Analysis with CFHTLS Deep data
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
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
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HDAC Inhibition by LBH589 Affects Phenotype and Function of Human Myeloid Dendritic Cells
LBH589 is a novel pan-HDAC inhibitor which has potent antitumor activity in multiple myeloma and other hematologic malignancies. However, its impact on immune system has not been defined. We here evaluated the effects of LBH589 on human myeloid dendritic cells (DCs) at clinically relevant concentrations. Exposure to LBH589 affected the surface molecule expression on immature and mature DCs, associated with DC maturation (CD83â), antigen presentation (HLA-ABCâ), and T cell co-stimulation (CD40â and CD86â). LBH589 decreased both protein and polysaccharide antigen uptake capacities by DCs. Importantly, LBH589 impaired DCs function to stimulate antigen-specific immune responses, resulting in the significant reduction of invariant NKT cell (CD1d-restricted) and T cell (MHC-restricted) activation in innate and adaptive immunity. LBH589 also significantly repressed the production of IL-6, IL-10, IL-12p70, IL-23 and TNF-α by TLR3 and TLR4-induced DCs activation, indicating an important role of HDAC activity in immune regulation and inflammation. RelB, a component of NF-ÎșB signaling pathway, was the key component regulated by HDAC inhibition in DCs. Together, our preclinical study demonstrates that LBH589 significantly impairs phenotype and function of DCs, indicating a need for monitoring the immune status in patients receiving HDAC inhibitor therapy. It also provides a rationale to evaluate LBH589 activity for the treatment of inflammation
Non-adiabatic primordial fluctuations
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
Womenâs Empowerment in Action: Evidence from a Randomized Control Trial in Africa €
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 womenâs empowerment in the worldâs 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 âŠndings indicate that womenâs 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 ClassiâŠcations: I25, J13, J24, O12
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