23,556 research outputs found
Mission Drift of large MFIs?
Since the Mexican Microfinance Institution (MFI) Compartamos went public in 2007 â whereby promoting NGOs and private investors earned about USD 425 million â leading journals and magazines have repeatedly run rather sceptical articles about microfinance. They are mostly inspired by antagonists of MFIs growing into market driven enterprises. This antagonism has been blended with contemplation about assumed âsubprime issuesâ of microfinance. However, the sector showed a steady performance, different from most other segments of the financial sector. The unholy blend of these two lines of thought risks to create an unwarranted image of microfinance.Microfinance; Mission Drift; Subprime; Sustainability
CMB Lensing Constraints on Neutrinos and Dark Energy
Signatures of lensing of the cosmic microwave background radiation by
gravitational potentials along the line of sight carry with them information on
the matter distribution, neutrino masses, and dark energy properties. We
examine the constraints that Planck, PolarBear, and CMBpol future data,
including from the B-mode polarization or the lensing potential, will be able
to place on these quantities. We simultaneously fit for neutrino mass and dark
energy equation of state including time variation and early dark energy
density, and compare the use of polarization power spectra with an optimal
quadratic estimator of the lensing. Results are given as a function of
systematics level from residual foreground contamination. A realistic CMBpol
experiment can effectively constrain the sum of neutrino masses to within 0.05
eV and the fraction of early dark energy to 0.002. We also present a
surprisingly simple prescription for calculating dark energy equation of state
constraints in combination with supernova distances from JDEM.Comment: 18 pages, 14 figures. Small changes made to match version to be
published in Phys. Rev.
Uraltsev Sum Rule in Bakamjian-Thomas Quark Models
We show that the sum rule recently proved by Uraltsev in the heavy quark
limit of QCD holds in relativistic quark models \`a la Bakamjian and Thomas,
that were already shown to satisfy Isgur-Wise scaling and Bjorken sum rule.
This new sum rule provides a {\it rationale} for the lower bound of the slope
of the elastic IW function obtained within the BT
formalism some years ago. Uraltsev sum rule suggests an inequality
. This difference is interpreted in the BT
formalism as due to the Wigner rotation of the light quark spin, independently
of a possible LS force. In BT models, the sum rule convergence is very fast,
the state giving the essential contribution in most of the
phenomenological potential models. We underline that there is a serious
problem, in the heavy quark limit of QCD, between theory and experiment for the
decays , independently of any model
calculation.Comment: 16 pages, Late
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