The Complex Links Between Governance and Biodiversity

We argue that two problems weaken the claims of those who link corruption and the exploitation of natural resources. The first is conceptual. Studies that use national level indicators of corruption fail to note that corruption comes in many forms, at multiple levels, and may or may not affect resource use. Without a clear causal model of the mechanism by which corruption affects resources, one should treat with caution any estimated relationship between corruption and the state of natural resources. The second problem is methodological: Simple models linking corruption measures and natural resource use typically do not account for other important causes and control variables pivotal to the relationship between humans and natural resources. By way of illustration of these two general concerns, we demonstrate that the findings of a well known recent study that posits a link between corruption and decreases in forests, elephants, and rhinoceros are fragile to simple conceptual and methodological refinements

FOOD AID TARGETING, SHOCKS AND PRIVATE TRANSFERS AMONG EAST AFRICAN PASTORALISTS

Public transfers of food aid are intended largely to support vulnerable populations in times of stress. We use high frequency panel data among Ethiopian and Kenyan pastoralists to test the efficacy of food aid targeting under three different targeting modalities, food aid's responsiveness to different types of shocks, and its relationship to private transfers. We find that self-targeting food-for-work or indicator-targeted free food distribution more effectively reach the poor than does food aid distributed according to community-based targeting. Food aid flows do not respond significantly to either covariate, community-level income or asset shocks, nor to idiosyncratic, household-level income or asset shocks. Rather, food aid flows appear to respond mainly to more readily observable rainfall measures. Finally, food aid does not appear to affect private transfers in any meaningful way, either by crowding out private gifts to recipient households nor by stimulating increased gifts by food aid recipients.Food Security and Poverty,

Test of shell-model interactions for nuclear structure calculations

The binding energy and excitation spectra of 6Li are calculated in a no-core shell-model space giving encouraging results. The results of this calculation are then treated as a theoretical experiment, against which different effective-interaction approximations are compared. In this way insight into the perturbation expansion for the effective interaction is obtained

Optimal learning rules for discrete synapses

There is evidence that biological synapses have a limited number of discrete weight states. Memory storage with such synapses behaves quite differently from synapses with unbounded, continuous weights, as old memories are automatically overwritten by new memories. Consequently, there has been substantial discussion about how this affects learning and storage capacity. In this paper, we calculate the storage capacity of discrete, bounded synapses in terms of Shannon information. We use this to optimize the learning rules and investigate how the maximum information capacity depends on the number of synapses, the number of synaptic states, and the coding sparseness. Below a certain critical number of synapses per neuron (comparable to numbers found in biology), we find that storage is similar to unbounded, continuous synapses. Hence, discrete synapses do not necessarily have lower storage capacity

AS-204/LM-1 launch vehicle operational flight trajectory

Apollo Saturn-204/LM-1 launch vehicle operational flight trajector

Universality of Decay out of Superdeformed Bands in the 190 Mass Region

Superdeformed nuclei in the 190 mass region exhibit a striking universality in their decay-out profiles. We show that this universality can be explained in the two-level model of superdeformed decay as related to a strong separation of energy scales: a higher scale related to the nuclear interactions, and a lower scale caused by electromagnetic decay. Furthermore, we present the results of the two-level model for all decays for which sufficient data are known, including statistical extraction of the matrix element for tunneling through the potential barrier.Comment: 7 pages, 3 figures. v2: some minor clarifications, minor correction to Fig.

Can Food-for-Work Programmes Reduce Vulnerability?

Famine, Food aid, Poverty, Public employment programmes, Transfers

U.S. Food Aid and Agricultural Cargo Preference Policy

Replaced with revised version of paper 07/20/10.Food Aid Policy, Cargo Preference, Agricultural and Food Policy, Food Security and Poverty,

Perturbative Effective Theory in an Oscillator Basis?

The effective interaction/operator problem in nuclear physics is believed to be highly nonperturbative, requiring extended high-momentum spaces for accurate solution. We trace this to difficulties that arise at both short and long distances when the included space is defined in terms of a basis of harmonic oscillator Slater determinants. We show, in the simplest case of the deuteron, that both difficulties can be circumvented, yielding highly perturbative results in the potential even for modest (~6hw) included spaces.Comment: 10 pages, 4 figure