Assessing the allocation of Italian foreign aid

This paper provides an assessment of Italian aid policy during the period 1983-2006. In comparison with other donors (DAC and G-7), the main stylized facts are: persistently lower aid/GDP ratio, greater recourse to multilateral channels, a higher percentage of “tied†flows and relatively greater recourse to debt relief. Drawing on the empirical literature on aid allocation, we estimate the determinants of Italy’s bilateral aid. We use three groups of explanatory variables, reflecting national-interest, humanitarian and selectivity-related motivations. We find that the distribution of Italian bilateral resources is significantly affected by both national-interest (like foreign policy or trade) and humanitarian motives, related to recipients’ needs; the latter’s role, in particular, seems to have strengthened over time. There is ample room for improving selectivity, i.e., the capacity to direct ODA flows to “deserving†countries, where better policies and institutions are likely to increase aid effectiveness.Italian foreign aid, aid allocation, donor motives, economic development.

Does aid buy votes?

We use data for 143 developing countries during the period 1980-2004 to study empirically the relationship between multilateral aid (as proxied by IDA flows) and support for US foreign policy, as measured by voting alignment at the United Nations General Assembly. Our identifica¬tion strategy exploits exogenous variations in international commodity prices and natural disasters to address causality from aid to voting. Our results suggest that, even though multilateral and bilateral aid flows are both associated with greater voting alignment, the causal effect of multilateral aid is not significantly different from zero. This result is robust to controlling for other determinants of voting patterns, for unobserved heterogeneity at the country level and for common time trends.foreign aid, UN Assembly, voting, international financial institutions

Rearrangement procedures in regenerative multibeammobile communications satellites with frequency reuse

After a short overview on the European tendencies about a Land Mobile Satellite Service, this paper describes an advanced system architecture, based on multiple spot-beams and on-board processing, capable of providing message and voice services over a wide European coverage, including some North-Africa and Middle-East countries. A remarkable problem associated with spot-beam configurations is the requirement for flexibility in the capacity offer to the various coverage areas. This means incorporating procedures for changing the on-board modulator-to-spot associations, respecting the constraints imposed by frequency reuse. After discussing the requirements of the rearrangement procedure, an on-purpose algorithm is presented. This paper is derived from work performed on contract to the European Space Agency (ESA)

Reinterpreting the development of extensive air showers initiated by nuclei and photons

Ultra-high energy cosmic rays (UHECRs) interacting with the atmosphere generate extensive air showers (EAS) of secondary particles. The depth corresponding to the maximum development of the shower, \Xmax, is a well-known observable for determining the nature of the primary cosmic ray which initiated the cascade process. In this paper, we present an empirical model to describe the distribution of \Xmax for EAS initiated by nuclei, in the energy range from $10^{17}$ eV up to $10^{21}$ eV, and by photons, in the energy range from $10^{17}$ eV up to $10^{19.6}$ eV. Our model adopts the generalized Gumbel distribution motivated by the relationship between the generalized Gumbel statistics and the distribution of the sum of non-identically distributed variables in dissipative stochastic systems. We provide an analytical expression for describing the \Xmax distribution for photons and for nuclei, and for their first two statistical moments, namely \langle \Xmax\rangle and \sigma^{2}(\Xmax). The impact of the hadronic interaction model is investigated in detail, even in the case of the most up-to-date models accounting for LHC observations. We also briefly discuss the differences with a more classical approach and an application to the experimental data based on information theory.Comment: 21 pages, 4 tables, 8 figure

Transport proteins determine drug sensitivity and resistance in a protozoan parasite, Trypanosoma brucei

Drug resistance in pathogenic protozoa is very often caused by changes to the ‘transportome’ of the parasites. In Trypanosoma brucei, several transporters have been implicated in uptake of the main classes of drugs, diamidines and melaminophenyl arsenicals. The resistance mechanism had been thought to be due to loss of a transporter known to carry both types of agents: the aminopurine transporter P2, encoded by the gene TbAT1. However, although loss of P2 activity is well-documented as the cause of resistance to the veterinary diamidine diminazene aceturate (Berenil®), cross-resistance between the human-use arsenical melarsoprol and the diamidine pentamidine (MPXR) is the result of loss of a separate High Affinity Pentamidine Transporter (HAPT1). A genome-wide RNAi library screen for resistance to pentamidine, published in 2012, gave the key to the genetic identity of HAPT1 by linking the phenomenon to a locus that contains the closely related T. brucei aquaglyceroporin genes TbAQP2 and TbAQP3. Further analysis determined that knockdown of only one pore, TbAQP2, produced the MPXR phenotype. TbAQP2 is an unconventional aquaglyceroporin with unique residues in the “selectivity region” of the pore, and it was found that in several MPXR lab strains the WT gene was either absent or replaced by a chimeric protein, recombined with parts of TbAQP3. Importantly, wild-type AQP2 was also absent in field isolates of T. b. gambiense, correlating with the outcome of melarsoprol treatment. Expression of a wild-type copy of TbAQP2 in even the most resistant strain completely reversed MPXR and re-introduced HAPT1 function and transport kinetics. Expression of TbAQP2 in Leishmania mexicana introduced a pentamidine transport activity indistinguishable from HAPT1. Although TbAQP2 has been shown to function as a classical aquaglyceroporin it is now clear that it is also a high affinity drug transporter, HAPT1. We discuss here a possible structural rationale for this remarkable ability

Message handling system concepts and services in a land mobile satellite system

A network architecture containing the capabilities offered by the Message Handling System (MHS) to the PRODAT Land Mobile Satellite System (LMSS) is described taking into account the constraints of a preexisting satellite system which is going to become operational. The mapping between MHS services and PRODAT requirements is also reported and shows that the supplied performance can be significantly enhanced to both fixed and mobile users. The impact of the insertion of additional features on the system structure, especially on the centralized control unit, are also addressed

Layered water Cherenkov detector for the study of ultra high energy cosmic rays

We present a new design for the water Cherenkov detectors that are in use in various cosmic ray observatories. This novel design can provide a significant improvement in the independent measurement of the muonic and electromagnetic component of extensive air showers. From such multi-component data an event by event classification of the primary cosmic ray mass becomes possible. According to popular hadronic interaction models, such as EPOS-LHC or QGSJetII-04, the discriminating power between iron and hydrogen primaries reaches Fisher values of $\sim$ 2 or above for energies in excess of $10^{19}$ eV with a detector array layout similar to that of the Pierre Auger Observatory.Comment: 17 pages, 15 figures, submitted to Nuclear Instruments and Methods

Molecular Bremsstrahlung Radiation at GHz Frequencies in Air

A detection technique for ultra-high energy cosmic rays, complementary to the fluorescence technique, would be the use of the molecular Bremsstrahlung radiation emitted by low-energy ionization electrons left after the passage of the showers in the atmosphere. In this article, a detailed estimate of the spectral intensity of photons at ground level originating from this radiation is presented. The spectral intensity expected from the passage of the high-energy electrons of the cascade is also estimated. The absorption of the photons in the plasma of electrons/neutral molecules is shown to be negligible. The obtained spectral intensity is shown to be $2\times10^{-21}$W cm$^{-2}$ GHz$^{-1}$ at 10 km from the shower core for a vertical shower induced by a proton of $10^{17.5}$ eV. In addition, a recent measurement of Bremsstrahlung radiation in air at gigahertz frequencies from a beam of electrons produced at 95 keV by an electron gun is also discussed and reasonably reproduced by the model.Comment: 20 pages, 9 figures, figures (2,4,7) improved in v2, accepted by Phys. Rev.