Networks of micro and small enterprise banks : a contribution to financial sector development : [Version March 2005]

The paper is a follow-up to an article published in Technique Financière et Developpement in 2000 (see the appendix to the hardcopy version), which portrayed the first results of a new strategy in the field of development finance implemented in South-East Europe. This strategy consists in creating microfinance banks as greenfield investments, that is, of building up new banks which specialise in providing credit and other financial services to micro and small enterprises, instead of transforming existing credit-granting NGOs into formal banks, which had been the dominant approach in the 1990s. The present paper shows that this strategy has, in the course of the last five years, led to the emergence of a network of microfinance banks operating in several parts of the world. After discussing why financial sector development is a crucial determinant of general social and economic development and contrasting the new strategy to former approaches in the area of development finance, the paper provides information about the shareholder composition and the investment portfolio of what is at present the world's largest and most successful network of microfinance banks. This network is a good example of a well-functioning "private public partnership". The paper then provides performance figures and discusses why the creation of such a network seems to be a particularly promising approach to the creation of financially self-sustaining financial institutions with a clear developmental objective

Pion Loop Contribution to the Electromagnetic Pion Charge Radius

A phenomenological Dyson-Schwinger equation approach to QCD, formalised in terms of a QCD based model field theory, is used to calculate the electromagnetic charge radius of the pion. The contributions from the quark core and pion loop, as defined in this approach, are identified and compared. It is shown explicitly that the divergence of the charge radius in the chiral limit is due to the pion loop and that, at the physical value of the pion mass, this loop contributes less than 15\% to $\langle r^2_\pi\rangle$; i.e. the quark core is the dominant determining characteristic for the pion. This suggests that quark based models which fail to reproduce the $\ln\,m_\pi$ divergence of $\langle r^2_\pi\rangle$ may nevertheless incorporate the dominant characteristic of the pion: its quark core.Comment: 22 Pages, 5 figures uuencoded and appended to this file, REVTEX 3.0. ANL-PHY-7663-TH-93, UNITUE-THEP-13/199

Networks of micro and small enterprise banks : a contribution to financial sector development :[Version January 2004]

The paper is a follow-up to an article published in Technique Financière et Developpement in 2000 (see the appendix to the hardcopy version), which portrayed the first results of a new strategy in the field of development finance implemented in South-East Europe. This strategy consists in creating microfinance banks as greenfield investments, that is, of building up new banks which specialise in providing credit and other financial services to micro and small enterprises, instead of transforming existing credit-granting NGOs into formal banks, which had been the dominant approach in the 1990s. The present paper shows that this strategy has, in the course of the last five years, led to the emergence of a network of microfinance banks operating in several parts of the world. After discussing why financial sector development is a crucial determinant of general social and economic development and contrasting the new strategy to former approaches in the area of development finance, the paper provides information about the shareholder composition and the investment portfolio of what is at present the world's largest and most successful network of microfinance banks. This network is a good example of a well-functioning "private public partnership". The paper then provides performance figures and discusses why the creation of such a network seems to be a particularly promising approach to the creation of financially self-sustaining financial institutions with a clear developmental objective

The mutational meltdown in asexual populations

Loss of fitness due to the accumulation of deleterious mutations appears to be inevitable in small, obligately asexual populations, as these are incapable of reconstituting highly fit genotypes by recombination or back mutation. The cumulative buildup of such mutations is expected to lead to an eventual reduction in population size, and this facilitates the chance accumulation of future mutations. This synergistic interaction between population size reduction and mutation accumulation leads to an extinction process known as the mutational meltdown, and provides a powerful explanation for the rarity of obligate asexuality. We give an overview of the theory of the mutational meltdown, showing how the process depends on the demographic properties of a population, the properties of mutations, and the relationship between fitness and number of mutations incurred

Gamma rays from extragalactic radio sources

It is proposed that the important connection between 3C 273 and 3C 279, the first two extragalactic sources detected at greater than 100 MeV energies, is their superluminal nature. In support of this conjecture, we propose a radiation mechanism that focuses gamma rays in the superluminal direction, due to Compton scattering of accretion-disk photons by relativistic nonthermal electrons in the jet

Symmetry energy in nuclear density functional theory

The nuclear symmetry energy represents a response to the neutron-proton asymmetry. In this survey we discuss various aspects of symmetry energy in the framework of nuclear density functional theory, considering both non-relativistic and relativistic self-consistent mean-field realizations side-by-side. Key observables pertaining to bulk nucleonic matter and finite nuclei are reviewed. Constraints on the symmetry energy and correlations between observables and symmetry-energy parameters, using statistical covariance analysis, are investigated. Perspectives for future work are outlined in the context of ongoing experimental efforts.Comment: 14 pages, 8 figures, submitted to the Special EPJA Issue on "Symmetry Energy

Systematics of collective correlation energies from self-consistent mean-field calculations

The collective ground-state correlations stemming from low-lying quadrupole excitations are computed microscopically. To that end, the self-consistent mean-field model is employed on the basis of the Skyrme-Hartre-Fock (SHF) functional augmented by BCS pairing. The microscopic-macroscopic mapping is achieved by quadrupole-constrained mean-field calculations which are processed further in the generator-coordinate method (GCM) at the level of the Gaussian overlap approximation (GOA). We study the correlation effects on energy, charge radii, and surface thickness for a great variety of semi-magic nuclei. A key issue is to work out the influence of variations of the SHF functional. We find that collective ground-state correlations (GSC) are robust under change of nuclear bulk properties (e.g., effective mass, symmetry energy) or of spin-orbit coupling. Some dependence on the pairing strength is observed. This, however, does not change the general conclusion that collective GSC obey a general pattern and that their magnitudes are rather independent of the actual SHF parameters.Comment: 13 pages, 13 figure