Fleeing mass starvation: what we (do not) know about the famine-migration nexus.

The relationship between famine and migration has not been studied adequately to date. A systematic review of scholarship centred on famine and its demographic, political, and socioeconomic effects demonstrates the paucity of academic attention to the issue. This paper surveys the dominant hypotheses and findings regarding the connection between famine and migration. It delineates key questions that an interdisciplinary and case-based exploration of the subject should address, highlighting gaps in the literature with respect to population-level analyses. Primary observations about the literature reviewed include tenuous generalisations about the linkage between famine and migration and partial examination of the role of politics in enabling or prohibiting mobility during hunger-related crises. In addition, disciplinary silos influence which particular aspects of a famine are scrutinised and which are not appraised. In view of these concerns, international legal and humanitarian norms governing migration also need to pay closer attention to its association with famine.

Bacterial Methionine Metabolism Genes Influence Drosophila melanogaster Starvation Resistance.

Animal-associated microorganisms (microbiota) dramatically influence the nutritional and physiological traits of their hosts. To expand our understanding of such influences, we predicted bacterial genes that influence a quantitative animal trait by a comparative genomic approach, and we extended these predictions via mutant analysis. We focused on Drosophila melanogaster starvation resistance (SR). We first confirmed that D. melanogaster SR responds to the microbiota by demonstrating that bacterium-free flies have greater SR than flies bearing a standard 5-species microbial community, and we extended this analysis by revealing the species-specific influences of 38 genome-sequenced bacterial species on D. melanogaster SR. A subsequent metagenome-wide association analysis predicted bacterial genes with potential influence on D. melanogaster SR, among which were significant enrichments in bacterial genes for the metabolism of sulfur-containing amino acids and B vitamins. Dietary supplementation experiments established that the addition of methionine, but not B vitamins, to the diets significantly lowered D. melanogaster SR in a way that was additive, but not interactive, with the microbiota. A direct role for bacterial methionine metabolism genes in D. melanogaster SR was subsequently confirmed by analysis of flies that were reared individually with distinct methionine cycle Escherichia coli mutants. The correlated responses of D. melanogaster SR to bacterial methionine metabolism mutants and dietary modification are consistent with the established finding that bacteria can influence fly phenotypes through dietary modification, although we do not provide explicit evidence of this conclusion. Taken together, this work reveals that D. melanogaster SR is a microbiota-responsive trait, and specific bacterial genes underlie these influences.IMPORTANCE Extending descriptive studies of animal-associated microorganisms (microbiota) to define causal mechanistic bases for their influence on animal traits is an emerging imperative. In this study, we reveal that D. melanogaster starvation resistance (SR), a model quantitative trait in animal genetics, responds to the presence and identity of the microbiota. Using a predictive analysis, we reveal that the amino acid methionine has a key influence on D. melanogaster SR and show that bacterial methionine metabolism mutants alter normal patterns of SR in flies bearing the bacteria. Our data further suggest that these effects are additive, and we propose the untested hypothesis that, similar to bacterial effects on fruit fly triacylglyceride deposition, the bacterial influence may be through dietary modification. Together, these findings expand our understanding of the bacterial genetic basis for influence on a nutritionally relevant trait of a model animal host.

Deciphering a neuronal circuit that mediates appetite.

Hypothalamic neurons that co-express agouti-related protein (AgRP), neuropeptide Y and γ-aminobutyric acid (GABA) are known to promote feeding and weight gain by integration of various nutritional, hormonal, and neuronal signals. Ablation of these neurons in mice leads to cessation of feeding that is accompanied by activation of Fos in most regions where they project. Previous experiments have indicated that the ensuing starvation is due to aberrant activation of the parabrachial nucleus (PBN) and it could be prevented by facilitating GABA(A) receptor signalling in the PBN within a critical adaptation period. We speculated that loss of GABA signalling from AgRP-expressing neurons (AgRP neurons) within the PBN results in unopposed excitation of the PBN, which in turn inhibits feeding. However, the source of the excitatory inputs to the PBN was unknown. Here we show that glutamatergic neurons in the nucleus tractus solitarius (NTS) and caudal serotonergic neurons control the excitability of PBN neurons and inhibit feeding. Blockade of serotonin (5-HT(3)) receptor signalling in the NTS by either the chronic administration of ondansetron or the genetic inactivation of Tph2 in caudal serotonergic neurons that project to the NTS protects against starvation when AgRP neurons are ablated. Likewise, genetic inactivation of glutamatergic signalling by the NTS onto N-methyl D-aspartate-type glutamate receptors in the PBN prevents starvation. We also show that suppressing glutamatergic output of the PBN reinstates normal appetite after AgRP neuron ablation, whereas it promotes weight gain without AgRP neuron ablation. Thus we identify the PBN as a hub that integrates signals from several brain regions to bidirectionally modulate feeding and body weight.

[FORCE-FEEDING OR LIFE-SAVING? - DEALING WITH HUNGER STRIKES IN ISRAEL].

INTRODUCTION: Force feeding of fasting hunger-striking prisoners is the subject of considerable controversy in Israel and elsewhere, posing a direct conflict between two basic ethical values: that of human life and respect for autonomy. The Israel Medical Association, as well as the World Medical Association, has taken the position that force feeding of such prisoners is an act of torture and is therefore unethical. However this paper presents an opposing view, which recently became the law in Israel, that, whereas the rights of prisoners to decree a hunger strike as a form of protest should be respected, if the prolongation of the strike reaches a stage of clear and present danger to the life and health of a prisoner, the saving of the prisoner's life must take precedence over considerations of autonomy. The paper present the steps that should be taken, including extensive and empathic efforts to persuade the prisoner to end his/her fast; gaining the approval of a hospital's ethics committee; and gaining the approval of a district court judge; the feeding is to be carried out in the most humane and sensitive manner as befitting a lifesaving procedure for any patient. This position is consistent with Israel's Basic Law: Human Dignity and Liberty, Israel's Patient Rights Law, Israel's "Do not stand idly by your fellow man's blood" Law, with several Israeli court decisions and in keeping with the dominant Israeli culture. Finally, instructions for physicians who object to such measures are discussed, ascertaining the freedom of conscience as well as preserving the life of the hunger-strikers.

[Force-feeding of hunger-striking prisoners].

In contrast to the position of the World Medical Association and the Ethics Council of the Israel Medical Association, the author argues for forced-feeding of hunger-striking prisoners when their condition reaches a stage of danger of death or permanent injury. This position is based on the priority of human life over autonomy, and of a communitarian ethic. This position is supported by a District Court decision ordering the feeding of a hunger-striking prisoner, by a Supreme Court decision imposing surgery on a non-consenting prisoner, and in line with Israel's Patient's Right Law.

Exploring audience segmentation: investigating adopter categories to diffuse an innovation to prevent famine in rural Mozambique.

Audience segmentation is a useful tool for designing effective campaigns. Further, the efficiency promised in diffusion science rests to some degree on the existence of adopter categories that can be identified and used to strategically disseminate prevention innovations. This study investigates the potential to identify adopter categories in potential recipients (n = 127) of an innovation to prevent food shortages in Mozambique. A 5-class model was found using latent class analysis, but it showed important differences from existing descriptions of adopter categories. Implications for theory and practice are discussed.